Relation between secondary doping and phase separation in PEDOT:PSS films
NASA Astrophysics Data System (ADS)
Donoval, Martin; Micjan, Michal; Novota, Miroslav; Nevrela, Juraj; Kovacova, Sona; Pavuk, Milan; Juhasz, Peter; Jagelka, Martin; Kovac, Jaroslav; Jakabovic, Jan; Cigan, Marek; Weis, Martin
2017-02-01
Conductive copolymer poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) has been proposed as an alternative to transparent conductive oxides because of its flexibility, transparency, and low-cost production. Four different secondary dopants, namely N,N-dimethylformamide, ethyleneglycol, sorbitol, and dimethyl sulfoxide, have been used to improve the conductivity. The relation between the structure changes and conductivity enhancement is studied in detail. Atomic force microscopy study of the thin film surface reveals the phase separation of PEDOT and PSS. We demonstrate that secondary doping induces the phase separation as well as the conductivity enhancement.
SSWR 3.01B.1: National maps of watershed integrity and stream condition
This presentation reports on two separate studies conducted under SSWR 3.01B as part of an FY16 Annual Performance Reporting (APR) product for the Office of Management and Budget. Three separate but related studies were conducted. The first study used EPA’s StreamCat data...
Polymer membranes as separators for supercapacitors
NASA Astrophysics Data System (ADS)
Szubzda, Bronisław; Szmaja, Aleksandra; Ozimek, Mariusz; Mazurkiewicz, Sławomir
2014-12-01
The purpose of the studies described was to examine the influence of low-energy plasma modification of polyamide and polypropylene polymer nonwoven fabrics on the usable properties of supercapacitors when using these fabrics as the separator material. To achieve this goal the following investigations were carried out: testing the time required for electrolyte saturation of separators and the conductivity of the electrolyte contained in the separator, as well as electrochemical examinations of supercapacitor models in which the modified fabric separators were used. The tests conducted fully confirm the usability of this modification for cleaning the surface and improving the wettability of separators by the electrolyte, which in turn results in a significant decrease of the internal resistance of the supercapacitor, thus increasing the usable power of the device.
A combined gene and cell therapy approach for restoration of conduction.
Hofshi, Anat; Itzhaki, Ilanit; Gepstein, Amira; Arbel, Gil; Gross, Gil J; Gepstein, Lior
2011-01-01
Abnormal conduction underlies both bradyarrhythmias and re-entrant tachyarrhythmias. However, no practical way exists for restoring or improving conduction in areas of conduction slowing or block. This study sought to test the feasibility of a novel strategy for conduction repair using genetically engineered cells designed to form biological "conducting cables." An in vitro model of conduction block was established using spatially separated, spontaneously contracting, nonsynchronized human embryonic stem cell-derived cardiomyocytes clusters. Immunostaining, dye transfer, intracellular recordings, and multielectrode array (MEA) studies were performed to evaluate the ability of genetically engineered HEK293 cells, expressing the SCN5A-encoded Na(+) channel, to couple with cultured cardiomyocytes and to synchronize their electrical activity. Connexin-43 immunostaining and calcein dye-transfer experiments confirmed the formation of functional gap junctions between the engineered cells and neighboring cardiomyocytes. MEA and intracellular recordings were performed to assess the ability of the engineered cells to restore conduction in the co-cultures. Synchronization was defined by establishment of fixed local activation time differences between the cardiomyocytes clusters and convergence of their activation cycle lengths. Nontransfected control cells were able to induce synchronization between cardiomyocytes clusters separated by distances up to 300 μm (n = 21). In contrast, the Na(+) channel-expressing cells synchronized contractions between clusters separated by up to 1,050 μm, the longest distance studied (n = 23). Finally, engineered cells expressing the voltage-sensitive K(v)1.3 potassium channel prevented synchronization at any distance. Genetically engineered cells, transfected to express Na(+) channels, can form biological conducting cables bridging and coupling spatially separated cardiomyocytes. This novel cell therapy approach might be useful for the development of therapeutic strategies for both bradyarrhythmias and tachyarrhythmias. Copyright © 2011 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.
Separation as an Important Risk Factor for Suicide: A Systematic Review
ERIC Educational Resources Information Center
Ide, Naoko; Wyder, Marianne; Kolves, Kairi; De Leo, Diego
2010-01-01
Examining how different phases of relationship separation effects the development of suicidal behaviors has been largely ignored in suicide studies. The few studies conducted suggest that individuals experiencing the acute phase of marital/de facto separation may be at greater risk of suicide compared with those experiencing long-term separation…
The application of the electrodynamic separator in minerals beneficiation
NASA Astrophysics Data System (ADS)
Skowron, M.; Syrek, P.; Surowiak, A.
2017-05-01
The aim of presented paper is elaboration of methodology of upgrading natural minerals in example of chalcocite and bornite sample. The results were obtained by means of laboratory drum separator. This device operates in accordance to properties of materials, which in this case was electrical conductivity. The study contains the analysis of the forces occurring inside of electrodynamic separator chamber, that act on the particles of various electrical properties. Both, the potential and electric field strength distributions were calculated, with set of separators setpoints. Theoretical analysis influenced on separator parameters, and hence impacted the empirical results too. Next, the authors conducted empirical research on chalcocite and bornite beneficiation by means of electrodynamic separation. The results of this process were shown graphically in form of upgrading curves of chalcocite considering elementary copper and lead.
Vortex developments over steady and accelerated airfoils incorporating a trailing edge jet
NASA Technical Reports Server (NTRS)
Finaish, F.; Okong'o, N.; Frigerio, J.
1993-01-01
Computational and experimental studies are conducted to investigate the influence of a trailing edge jet on flow separation and subsequent vortex formation over steady and accelerated airfoils at high angles of attack. A computer code, employing the stream function-vorticity approach, is developed and utilized to conduct numerical experiments on the flow problem. To verify and economize such efforts, an experimental system is developed and incorporated into a subsonic wind tunnel where streamline and vortex flow visualization experiments are conducted. The study demonstrates the role of the trailing edge jet in controlling flow separation and subsequent vortex development for steady and accelerating flow at angles past the static stall angle of attack. The results suggest that the concept of the trailing edge jet may be utilized to control the characteristics of unsteady separated flows over lifting surfaces. This control possibility seems to be quite effective and could have a significant role in controlling unsteady separated flows.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-19
...-AA48 Traffic Separation Schemes: In the Strait of Juan de Fuca and Its Approaches; in Puget Sound and..., the Coast Guard codifies traffic separation schemes in the Strait of Juan de Fuca and its approaches.... These traffic separation schemes (TSSs) were validated by a Port Access Route Study (PARS) conducted...
Air-Ground Integration Experiment
DOT National Transportation Integrated Search
2002-01-01
could potentially shift aircraft separation responsibility from air traffic controllers to flight crews creating a'shared-separation' : authority environment Areal-time, human-in-the-loop study was conducted using facilities at NASA Ames Research Cen...
Children at Risk: Vulnerability/Resiliency to Psychopathology after Parental Separation/Divorce.
ERIC Educational Resources Information Center
McPhee, Jeffrey Thomas
This study explored factors within a child's social, familial, and intrapsychic system that mediate the effects on the child of parental separation/divorce. Using a sample of 52 children and 28 parents involved in contested divorce cases, structured interviews lasting 1.5 to 3 hours were conducted. Information about the separation, parental…
Parental separation/divorce in childhood and partnership outcomes at age 30.
Fergusson, David M; McLeod, Geraldine F H; John Horwood, L
2014-04-01
Previous research has found that children exposed to separation/divorce may also experience relationship problems in adulthood. The aim of this investigation was to examine this issue in a birth cohort of over 900 New Zealand children studied to age 30. Data were gathered over the course of the Christchurch Health and Development Study (CHDS). The CHDS is a 30 year longitudinal study of a birth cohort of 1265 children born in Christchurch (NZ) in 1977. The data collected included the following: (a) timing and number of parental separations and divorces from birth to 15 years; (b) partnership outcomes (16-30 years) of the number of cohabiting/marriage partnerships; positive partner relations; negative partner relations; partner adjustment/conduct problems; and interpartner violence victimization and perpetration; and (c) potential covariate factors. Study findings showed the presence of significant associations between childhood parental separations/divorces and number of cohabiting/marriage partnerships (16-30 years) (p < .001), negative partner relations (p = .021), extent of partner adjustment/conduct problems (p < .001), and perpetration of interpartner violence (p = .018). Childhood parental separation/divorce explained less than 2.5% of the variance in partnership outcomes. These associations were explained statistically by a series of covariate factors associated with childhood parental separation/divorce including parental history of illicit drug use, childhood sexual abuse, childhood conduct problems (7-9 years), interparental conflict and violence, childhood physical punishment/maltreatment, family socio-economic status at the child's birth, and parental history of criminality. Tests of gender interaction showed that the effect of childhood parental separations/divorces may be the same for males and females. Analysis of the number of childhood parental separations/divorces experienced into three age groups (birth to 5, 5-10 years and 10-15 years) yielded similar results. These findings suggest that the general associations between childhood parental separation/divorce and partner relationships in adulthood reflect the consequences of various contextual factors that are associated with childhood parental separation. © 2013 The Authors. Journal of Child Psychology and Psychiatry © 2013 Association for Child and Adolescent Mental Health.
Fabrication of Conductive Macroporous Structures Through Nano-phase Separation Method
NASA Astrophysics Data System (ADS)
Kim, Soohyun; Lee, Hyunjung
2018-03-01
Thermoelectric power generation performance is characterized on the basis of the figure of merit, which tends to be high in thermoelectric materials with high electrical conductivity and low thermal conductivity. Porous structures cause phonon scattering, which decreases thermal conductivity. In this study, we fabricated porous structures for thermoelectric devices via nano-phase separation of silica particles from a polyacrylonitrile (PAN) matrix via a sol-gel process. The porosity was determined by control of silica particle size with various the mixing ratio of tetraethylorthosilicate as the precursor of silica particles to PAN. High electrical conductivity was maintained by subsequent carbonization of the PAN matrix in spited of a high porosity. As the results, the conductive porous structures having porosity from 13.9 to 83.3 (%) was successfully fabricated, keeping their electrical conductivities.
NASA Astrophysics Data System (ADS)
Hayashi, S.; Mishima, F.; Akiyama, Y.; Nishijima, S.
2011-11-01
In the industrial plants processing highly viscous fluid such as foods or industrial products, it is necessary to remove the metallic wear debris originating from pipe in manufacturing line which triggers quality loss. In this study, we developed a high gradient magnetic separation (HGMS) system which consists of superconducting magnet to remove the metallic wear debris. The magnetic separation experiment and the particle trajectory simulation were conducted with polyvinyl alcohol (PVA) as a model material (viscosity coefficient was 10 Pa s, which is 10,000 times higher than that in water). In order to develop a magnetic separation system for practical use, the particle trajectory simulation by using solenoidal superconducting magnet was conducted, and the possibility of the magnetic separation for removing ferromagnetic stainless steel (SUS) particles in highly viscous fluid of 10 Pa s was indicated. Based on the results, the number of filters to obtain required separation efficiency was examined to design the practical separation system.
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.
NASA Astrophysics Data System (ADS)
Gaitonde, Aalok Jaisheela Uday
Increasing usage and recent accidents due to lithium-ion (Li-ion) batteries exploding or catching on fire has inspired research on the characterization and thermal management of these batteries. In cylindrical 18650 cells, heat generated during the battery's charge/discharge cycle is poorly dissipated to the surrounding through its metallic case due to the poor thermal conductivity of the jelly roll, which is spirally wound with many interfaces between electrodes and the polymeric separator. This work presents a technique to measure the thermal conduction across the metallic case-plastic separator interface, which ultimately limits heat transfer out of the jelly roll. The polymeric separator and metallic case are harvested from discharged commercial 18650 battery cells for thermal testing. A miniaturized version of the reference bar method enables measurements of the interface resistance between the case and the separator by establishing a temperature gradient across a multilayer stack consisting of two reference layers of known thermal conductivity and the case-separator sample. The case-separator interfacial conductance is reported for a range of case temperatures and interface pressures. The mean thermal conductance across the case-separator interface is 670 +/- 275 W/(m2K) and no significant temperature or pressure dependence is observed. The effective thermal conductivity of the battery stack is measured to be 0.27 W/m/K and 0.32 W/m/K in linear and radial configurations, respectively. Many techniques for fabricating battery electrodes involve coating particles of the active materials on metallic current collectors. The impact of mechanical shearing on the resultant thermal properties of these packed particle beds during the fabrication process has not yet been studied. Thus, the final portion of this thesis designs and validates a measurement system to measure the effects of mechanical shearing on the thermal conductivity of packed granular beds. This system simultaneously shears the sample while applying a temperature gradient across the particle bed, enabling thermal conductivity measurements using a radial equivalent of the conventional reference bar method. Results of this research, which includes characterization of thermal conductance across the rate limiting separator-case interface, will help improve the design and reliability of lithium ion batteries. Cells of larger dimension and capacity could also be achieved by the improved understanding of thermal transport across the microscopic electrode stack. Better analytic models of the thermal response of the batteries could be constructed, by taking into account the interfacial conductance and thermal conductivity of the electrodes measured in this work. This is of particular importance in the current circumstances, where accidents and safety issues related to lithium ion batteries are on the increase.
An investigation of the unsteady flow associated with plume induced flow separation
NASA Technical Reports Server (NTRS)
Boggess, A. L., Jr.
1972-01-01
A wind tunnel study of the basic nature of plume induced flow separation is reported with emphasis on the unsteady aspects of the flow. Testing was conducted in a 6 inch by 6 inch blow-down supersonic wind tunnel. A cone-cylinder model with a pluming jet was used as the test model. Tests were conducted with a systematic variation in Mach number and plume pressure. Results of the tests are presented in the form of root-mean-squared surface pressure levels, power spectral densities, photographs of the flow field from which shock angles and separation lengths were taken, and time-averaged surface pressure profiles.
Brian C. McCarthy; Matthew A. Albrecht
2005-01-01
We conducted a study of hardwood regeneration in the mixed oak forests of unglaciated southeastern Ohio following various silvicultural practices. Our study was conducted at three separate forests within the region.
Lewis, Nathan S.; Spurgeon, Joshua M.
2016-10-25
The solar fuels generator includes an ionically conductive separator between a gaseous first phase and a second phase. A photoanode uses one or more components of the first phase to generate cations during operation of the solar fuels generator. A cation conduit is positioned provides a pathway along which the cations travel from the photoanode to the separator. The separator conducts the cations. A second solid cation conduit conducts the cations from the separator to a photocathode.
Pollen-mediated gene flow from transgenic cotton is constrained by physical isolation measures.
Yan, Shuo; Zhu, Weilong; Zhang, Boyu; Zhang, Xinmi; Zhu, Jialin; Shi, Jizhe; Wu, Pengxiang; Wu, Fengming; Li, Xiangrui; Zhang, Qingwen; Liu, Xiaoxia
2018-02-12
The public concern about pollen-mediated gene flow (PGF) from genetically modified (GM) crops to non-GM crops heats up in recent years over China. In the current study, we conducted greenhouse and field experiments to measure PGF with various physical isolation measures, including 90, 80, 60 and 40 holes/cm 2 separation nets and Sorghum bicolor, Zea mays and Lycopersicon esculentum separation crops between GM cotton and non-GM line (Shiyuan321) by seed DNA test during 2013 to 2015, and pollen grain dyeing was also conducted to assess the pollen flow in greenhouse during 2013. Our results revealed that (1) PGF varied depending on the physical isolation measures. PGF was the lowest with 90 holes/cm 2 separation net and S. bicolor separation crop, and the highest with 40 holes/cm 2 separation net and no isolation measure. (2) Similar to PGF results, 90 holes/cm 2 separation net and S. bicolor separation crop could minimize the pollen dispersal. (3) PGF declined exponentially with increasing distance between GM cotton and Shiyuan321. Because of the production mode of farm household (limited cultivated area) in China, our study is particularly important, which is not only benefit for constraining PGF, but also has potential application value in practical production and the scientific researches.
NASA Astrophysics Data System (ADS)
Martis, R. R.; Misra, A.
2017-09-01
A numerical study is conducted to determine the effectiveness of six different microvortex generator geometries in controlling swept shock wave/boundary-layer interactions. The geometries considered are base ramp, base ramp with declining angle of 45°, blunt ramp, split ramp, thick vanes, and ramped vanes. Microvortex generators with a gap were found to be better suited for delaying the separation. Thick vanes showed the largest delay in separation among the devices studied.
A Motivational Explanation of Private Self-Consciousness.
ERIC Educational Resources Information Center
Franzoi, Stephen L.; And Others
Private self-consciousness (PSC) refers to the dispositional tendency to be attentive to the private, covert aspects of oneself. Studies were conducted to investigate whether there are motivational underpinnings for individual differences in level of PSC. Four separate studies were conducted at three different institutions. Study 1 (N=59) results…
Functioning of inorganic/organic battery separators in silver-zinc cells
NASA Technical Reports Server (NTRS)
Philipp, W. H.; May, C. E.
1976-01-01
The results of three experimental studies related to the inorganic/organic battery separator operating mechanism are described: saponification of the plasticizer, resistivity of the simulated separators, and zincate diffusion through the separators. The inorganic/organic separator appears to be a particular example of a general class of ionic conducting films composed of inorganic fillers and/or substrates bonded together by an organic polymer containing an incompatible plasticizer that may be leached by the electrolyte. The I/O separator functions as a microporous film of varying tortuosity with essentially no specific chemical inhibition to zincate diffusion.
Flow Solution for Advanced Separate Flow Nozzles Response A: Structured Grid Navier-Stokes Approach
NASA Technical Reports Server (NTRS)
Kenzakowski, D. C.; Shipman, J.; Dash, S. M.; Saiyed, Naseem (Technical Monitor)
2001-01-01
NASA Glenn Research Center funded a computational study to investigate the effect of chevrons and tabs on the exhaust plume from separate flow nozzles. Numerical studies were conducted at typical takeoff power with 0.28 M flight speed. Report provides numerical data and insights into the mechanisms responsible for increased mixing.
Lu, Sen; Ren, Tusheng; Lu, Yili; Meng, Ping; Zhang, Jinsong
2017-01-05
The thermal conductivity of dry soils is related closely to air pressure and the contact areas between solid particles. In this study, the thermal conductivity of two-phase soil systems was determined under reduced and increased air pressures. The thermal separation of soil particles, i.e., the characteristic dimension of the pore space (d), was then estimated based on the relationship between soil thermal conductivity and air pressure. Results showed that under both reduced and increased air pressures, d estimations were significantly larger than the geometrical mean separation of solid particles (D), which suggested that conductive heat transfer through solid particles dominated heat transfer in dry soils. The increased air pressure approach gave d values lower than that of the reduced air pressure method. With increasing air pressure, more collisions between gas molecules and solid surface occurred in micro-pores and intra-aggregate pores due to the reduction of mean free path of air molecules. Compared to the reduced air pressure approach, the increased air pressure approach expressed more micro-pore structure attributes in heat transfer. We concluded that measuring thermal conductivity under increased air pressure procedures gave better-quality d values, and improved soil micro-pore structure estimation.
Optimization of the oxidant supply system for combined cycle MHD power plants
NASA Technical Reports Server (NTRS)
Juhasz, A. J.
1982-01-01
An in-depth study was conducted to determine what, if any, improvements could be made on the oxidant supply system for combined cycle MHD power plants which could be reflected in higher thermal efficiency and a reduction in the cost of electricity, COE. A systematic analysis of air separation process varitions which showed that the specific energy consumption could be minimized when the product stream oxygen concentration is about 70 mole percent was conducted. The use of advanced air compressors, having variable speed and guide vane position control, results in additional power savings. The study also led to the conceptual design of a new air separation process, sized for a 500 MW sub e MHD plant, referred to a internal compression is discussed. In addition to its lower overall energy consumption, potential capital cost savings were identified for air separation plants using this process when constructed in a single large air separation train rather than multiple parallel trains, typical of conventional practice.
Separators - Technology review: Ceramic based separators for secondary batteries
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nestler, Tina; Schmid, Robert; Münchgesang, Wolfram
Besides a continuous increase of the worldwide use of electricity, the electric energy storage technology market is a growing sector. At the latest since the German energy transition ('Energiewende') was announced, technological solutions for the storage of renewable energy have been intensively studied. Storage technologies in various forms are commercially available. A widespread technology is the electrochemical cell. Here the cost per kWh, e. g. determined by energy density, production process and cycle life, is of main interest. Commonly, an electrochemical cell consists of an anode and a cathode that are separated by an ion permeable or ion conductive membranemore » - the separator - as one of the main components. Many applications use polymeric separators whose pores are filled with liquid electrolyte, providing high power densities. However, problems arise from different failure mechanisms during cell operation, which can affect the integrity and functionality of these separators. In the case of excessive heating or mechanical damage, the polymeric separators become an incalculable security risk. Furthermore, the growth of metallic dendrites between the electrodes leads to unwanted short circuits. In order to minimize these risks, temperature stable and non-flammable ceramic particles can be added, forming so-called composite separators. Full ceramic separators, in turn, are currently commercially used only for high-temperature operation systems, due to their comparably low ion conductivity at room temperature. However, as security and lifetime demands increase, these materials turn into focus also for future room temperature applications. Hence, growing research effort is being spent on the improvement of the ion conductivity of these ceramic solid electrolyte materials, acting as separator and electrolyte at the same time. Starting with a short overview of available separator technologies and the separator market, this review focuses on ceramic-based separators. Two prominent examples, the lithium-ion and sodium-sulfur battery, are described to show the current stage of development. New routes are presented as promising technologies for safe and long-life electrochemical storage cells.« less
Separators - Technology review: Ceramic based separators for secondary batteries
NASA Astrophysics Data System (ADS)
Nestler, Tina; Schmid, Robert; Münchgesang, Wolfram; Bazhenov, Vasilii; Schilm, Jochen; Leisegang, Tilmann; Meyer, Dirk C.
2014-06-01
Besides a continuous increase of the worldwide use of electricity, the electric energy storage technology market is a growing sector. At the latest since the German energy transition ("Energiewende") was announced, technological solutions for the storage of renewable energy have been intensively studied. Storage technologies in various forms are commercially available. A widespread technology is the electrochemical cell. Here the cost per kWh, e. g. determined by energy density, production process and cycle life, is of main interest. Commonly, an electrochemical cell consists of an anode and a cathode that are separated by an ion permeable or ion conductive membrane - the separator - as one of the main components. Many applications use polymeric separators whose pores are filled with liquid electrolyte, providing high power densities. However, problems arise from different failure mechanisms during cell operation, which can affect the integrity and functionality of these separators. In the case of excessive heating or mechanical damage, the polymeric separators become an incalculable security risk. Furthermore, the growth of metallic dendrites between the electrodes leads to unwanted short circuits. In order to minimize these risks, temperature stable and non-flammable ceramic particles can be added, forming so-called composite separators. Full ceramic separators, in turn, are currently commercially used only for high-temperature operation systems, due to their comparably low ion conductivity at room temperature. However, as security and lifetime demands increase, these materials turn into focus also for future room temperature applications. Hence, growing research effort is being spent on the improvement of the ion conductivity of these ceramic solid electrolyte materials, acting as separator and electrolyte at the same time. Starting with a short overview of available separator technologies and the separator market, this review focuses on ceramic-based separators. Two prominent examples, the lithium-ion and sodium-sulfur battery, are described to show the current stage of development. New routes are presented as promising technologies for safe and long-life electrochemical storage cells.
Ion Conduction in Microphase-Separated Block Copolymer Electrolytes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kambe, Yu; Arges, Christopher G.; Patel, Shrayesh
2017-01-01
Microphase separation of block copolymers provides a promising route towards engineering a mechanically robust ion conducting film for electrochemical devices. The separation into two different nano-domains enables the film to simultaneously exhibit both high ion conductivity and mechanical robustness, material properties inversely related in most homopolymer and random copolymer electrolytes. To exhibit the maximum conductivity and mechanical robustness, both domains would span across macroscopic length scales enabling uninterrupted ion conduction. One way to achieve this architecture is through external alignment fields that are applied during the microphase separation process. In this review, we present the progress and challenges for aligningmore » the ionic domains in block copolymer electrolytes. A survey of alignment and characterization is followed by a discussion of how the nanoscale architecture affects the bulk conductivity and how alignment may be improved to maximize the number of participating conduction domains.« less
Mercury Capsule Separation Tests
1960-04-01
Mercury capsule separation from Redstone booster in the Altitude Wind Tunnel (AWT): NASA Lewis conducted full-scale separation tests of the posigrade rockets that were fired after the Redstone rockets burned out. The researchers studied the effect of the posigrade rockets firing on the Redstone booster and retrograde package. This film shows the Mercury capsule being mounted to the Redstone missile model in the Altitude Wind Tunnel. The capsule's engines are fired and it horizontally separates from the Atlas. After firing the capsule swings from an overhead crane.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Perry, D.D.; Bolcar, J.P.
1990-04-01
A study has been conducted to determine the effects of commercial degreasing solvents on the conductivity of an EPDM separable connector shield and two types of cable shields based on EPR and XLPE, respectively. Solvents tested included a chlorinated solvent based on 1,1,1-trichloroethane and several so-called citrus solvents consisting of the natural terpene, limonene, or blends of limonene with other hydrocarbons. All the solvents significantly degraded the conductivity of the EPR and EPDM materials, but had little effect on the XLPE cable shield. The solvents differed, however, in the extent of their effects, the rate of recovery of conductivity aftermore » removal of the solvent, and the degree to which the original conductivity of the material was restored. The consequences of these results in terms of appropriate field use of these types of solvents by utility personnel are discussed.« less
Aramid Nanofiber Composites for Energy Storage Applications
NASA Astrophysics Data System (ADS)
Tung, Siu on
Lithium ion batteries and non-aqueous redox flow batteries represent two of the most important energy storage technologies to efficient electric vehicles and power grid, which are essential to decreasing U.S. dependence on fossil fuels and sustainable economic growth. Many of the developmental roadblocks for these batteries are related to the separator, an electrically insulating layer between the cathode and anode. Lithium dendrite growth has limited the performance and threatened the safety of lithium ion batteries by piercing the separator and causing internal shorts. In non-aqueous redox flow batteries, active material crossover through microporous separators and the general lack of a suitable ion conducting membrane has led to low operating efficiencies and rapid capacity fade. Developing new separators for these batteries involve the combination of different and sometimes seemingly contradictory properties, such as high ionic conductivity, mechanical stability, thermal stability, chemical stability, and selective permeability. In this dissertation, I present work on composites made from Kevlar-drived aramid nanofibers (ANF) through rational design and fabrication techniques. For lithium ion batteries, a dendrite suppressing layer-by-layer composite of ANF and polyethylene oxide is present with goals of high ionic conductivity, improved safety and thermal stability. For non-aqueous redox flow batteries, a nanoporous ANF separator with surface polyelectrolyte modification is used to achieve high coulombic efficiencies and cycle life in practical flow cells. Finally, manufacturability of ANF based separators is addressed through a prototype machine for continuous ANF separator production and a novel separator coated on anode assembly. In combination, these studies serve as a foundation for addressing the challenges in separator engineering for lithium ion batteries and redox flow batteries.
Follow-up Cost Study. TEX-SIS FOLLOW-UP SC5.
ERIC Educational Resources Information Center
Baugh, Ronald C.
This report presents data on the costs of follow-up studies, based on 29 separate follow-up studies conducted by eight public community/junior colleges in Texas. The purpose of this study, conducted by Navarro College as a subcontractor of Project FOLLOW-UP, was to provide data and information regarding the cost of follow-up studies that would be…
NASA Astrophysics Data System (ADS)
Hu, Yuanfang; Wang, Bingxi; Li, Xiao; Chen, Dongyang; Zhang, Weiying
2018-05-01
To develop high performance anion exchange membranes (AEMs), a novel bisphenol monomer bearing eight benzylmethyl groups at the outer edge of the molecule was synthesized, which after condensation polymerization with various amounts of 4,4‧-dihydroxydiphenylsulfone and 4,4‧-difluorobenzophenone yielded novel poly(arylene ether)s with densely located benzylmethyl groups. These benzylmethyl groups were then converted to quaternary ammonium groups by radical-initiated bromination and quaternization in tandem, leading to the emergence of densely quaternized poly(arylene ether sulfone)s (QA-PAEs) with controlled ion exchange capacities (IECs) ranging from 1.61 to 2.32 mmol g-1. Both small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM) studies revealed distinct phase separation in the QA-PAEs. The QA-PAE-40 with an IEC of 2.32 mmol g-1 exhibited a Br- conductivity of 9.2 mS cm-1 and a SO42- conductivity of 14.0 mS cm-1 at room temperature, much higher than those of a control membrane with a similar IEC but without obvious phase separation. Therefore, phase separation of AEMs was validated to be advantageous for the efficient conducting of anions. The experimental results also showed that the QA-PAEs were promising AEM materials, especially for non-alkaline applications.
Aircraft Carrier Flight Deck Fire Fighting Tactics and Equipment Evaluation Tests
1987-02-26
pattern nozzles; 8. proper fire fighting techniques for possible titanium ignition in an F-14 crash (deleted later by direction of FLSC, being studied ...separately); 9. effect of full fire involvement of "ready for flight" aircraft (deleted later by direction of FLSC, being studied separately). The...to refine and identify specific hardware and tactical requirements generated from the studies conducted during the scoping tests; 3. concept
Improving Ionic Conductivity and Lithium-Ion Transference Number in Lithium-Ion Battery Separators.
Zahn, Raphael; Lagadec, Marie Francine; Hess, Michael; Wood, Vanessa
2016-12-07
The microstructure of lithium-ion battery separators plays an important role in separator performance; however, here we show that a geometrical analysis falls short in predicting the lithium-ion transport in the electrolyte-filled pore space. By systematically modifying the surface chemistry of a commercial polyethylene separator while keeping its microstructure unchanged, we demonstrate that surface chemistry, which alters separator-electrolyte interactions, influences ionic conductivity and lithium-ion transference number. Changes in separator surface chemistry, particularly those that increase lithium-ion transference numbers can reduce voltage drops across the separator and improve C-rate capability.
Hoskins, Daniel L; Zhang, Xiaoyuan; Hickner, Michael A; Logan, Bruce E
2014-11-01
Separators are used to protect cathodes from biofouling and to avoid electrode short-circuiting, but they can adversely affect microbial fuel cell (MFC) performance. A spray method was used to apply a polyvinyl alcohol (PVA) separator to the cathode. Power densities were unaffected by the PVA separator (339±29mW/m(2)), compared to a control lacking a separator in a low conductivity solution (1mS/cm) similar to wastewater. Power was reduced with separators in solutions typical of laboratory tests (7-13mS/cm), compared to separatorless controls. The PVA separator produced more power in a separator assembly (SEA) configuration (444±8mW/m(2)) in the 1mS/cm solution, but power was reduced if a PVA or wipe separator was used in higher conductivity solutions with either Pt or activated carbon catalysts. Spray and cast PVA separators performed similarly, but the spray method is preferred as it was easier to apply and use. Copyright © 2014 Elsevier Ltd. All rights reserved.
Separation Anxiety Disorder in Childhood as a Risk Factor for Future Mental Illness
ERIC Educational Resources Information Center
Lewinsohn, Peter M.; Holm-Denoma, Jill M.; Small, Jason W.; Seeley, John R.; Joiner, Thomas E.
2008-01-01
A study to examine the association between childhood separation anxiety disorder (SAD) and the risk of the development of psychopathology during young adulthood was conducted. Results showed that SAD contributed to the risk for the development of internalizing disorders, which are panic and depression, but decreased the risk for externalizing…
Sample detection and analysis techniques for electrophoretic separation
NASA Technical Reports Server (NTRS)
Falb, R. D.; Hughes, K. E.; Powell, T. R.
1975-01-01
Methods for detecting and analyzing biological agents suitable for space flight operations were studied primarily by literature searches which were conducted of cell separation techniques. Detection methods discussed include: photometrometric, electric, radiometric, micrometry, ultrasonic, microscopic, and photographic. A bibliography, and a directory of vendors are included along with an index of commercial hardware.
Hutchinson, Joseph P; Johns, Cameron; Breadmore, Michael C; Hilder, Emily F; Guijt, Rosanne M; Lennard, Chris; Dicinoski, Greg; Haddad, Paul R
2008-11-01
Novel CE methods have been developed on portable instrumentation adapted to accommodate a capacitively coupled contactless conductivity detector for the separation and sensitive detection of inorganic anions and cations in post-blast explosive residues from homemade inorganic explosive devices. The methods presented combine sensitivity and speed of analysis for the wide range of inorganic ions used in this study. Separate methods were employed for the separation of anions and cations. The anion separation method utilised a low conductivity 70 mM Tris/70 mM CHES aqueous electrolyte (pH 8.6) with a 90 cm capillary coated with hexadimethrine bromide to reverse the EOF. Fifteen anions could be baseline separated in 7 min with detection limits in the range 27-240 microg/L. A selection of ten anions deemed most important in this application could be separated in 45 s on a shorter capillary (30.6 cm) using the same electrolyte. The cation separation method was performed on a 73 cm length of fused-silica capillary using an electrolyte system composed of 10 mM histidine and 50 mM acetic acid, at pH 4.2. The addition of the complexants, 1 mM hydroxyisobutyric acid and 0.7 mM 18-crown-6 ether, enhanced selectivity and allowed the separation of eleven inorganic cations in under 7 min with detection limits in the range 31-240 microg/L. The developed methods were successfully field tested on post-blast residues obtained from the controlled detonation of homemade explosive devices. Results were verified using ion chromatographic analyses of the same samples.
Rohatgi, Charu Vashisth; Dutta, Naba K.; Choudhury, Namita Roy
2015-01-01
In this work, we report separator membranes from crosslinking of two polymers, such as poly vinyl alcohol (PVA) with an ionic polymer poly(methyl vinyl ether-alt-maleic anhydride) (PMVE-MA). Such interpolymer-networked systems were extensively used for biomedical and desalination applications but they were not examined for their potential use as membranes or separators for batteries. Therefore, the chemical interactions between these two polymers and the influence of such crosslinking on physicochemical properties of the membrane are systematically investigated through rheology and by critical gel point study. The hydrogen bonding and the chemical interaction between PMVE-MA and PVA resulted in highly cross-linked membranes. Effect of the molecular weight of PVA on the membrane properties was also examined. The developed membranes were extensively characterized by studying their physicochemical properties (water uptake, swelling ratio, and conductivity), thermal and electrochemical properties using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermo-gravimetric analysis (TGA) and electrochemical impedance spectroscopy (EIS). The DSC study shows the presence of a single Tg in the membranes indicating compatibility of the two polymers in flexible and transparent films. The membranes show good stability and ion conductivity suitable for separator applications. PMID:28347019
ERIC Educational Resources Information Center
Apsche, Jack A.; Bass, Christopher K.; Murphy, Christopher J.
2004-01-01
This paper compares the results of two separate published studies regarding adolescent males with conduct disorders and/or personality disorders/traits. Both studies were published in the Behavior Analyst Today, Vol. 3, No. 4, Vol 5, No. 1, respectively. The concept is to evaluate two treatment research studies that represent "the best" practices…
Mixed ionic and electronic conducting membranes for hydrogen generation and separation
NASA Astrophysics Data System (ADS)
Cui, Hengdong
Dense mixed ionic and electronic conducting (MIEC) membranes are receiving increasing attention due to their potential for application as gas separation membranes to separate oxygen from air. The objective of this work is to study a novel, chemically-assisted separation process that utilizes oxygen-ion and electron-conducting MIECs for generating and separating hydrogen from steam. This research aims at exploring new routes and materials for high-purity hydrogen production for use in fuel cells and hydrogen-based internal combustion (IC) engines. In this approach, hydrocarbon fuel such as methane is fed to one side of the membrane, while steam is fed to the other side. The MIEC membrane separation process involves steam dissociation and oxidation of the fuel. The oxygen ions formed as a result of steam dissociation are transported across the membrane in a coupled transport process with electrons being transported in the opposite direction. Upon reaching the fuel side of the membrane, the oxygen ions oxidize the hydrocarbon. This process results in hydrogen production on the steam side of the membrane. The oxygen partial pressure gradient across the membrane is the driving force for this process. In this work, a novel, dual-phase composite MIEC membrane system comprising of rare-earth doped ceria with high oxygen ion conductivity and donor-doped strontium titanate with high electronic conductivity were investigated. The chemical diffusion coefficient and surface exchange coefficient have been measured using the electrical conductivity relaxation (ECR) technique. These two parameters control the rate of oxygen permeation across the membrane. The permeation data have been fit with a kinetic model that incorporates oxygen surface exchange on two sides of the membrane and bulk transport of oxygen through the membrane. This material has higher bulk diffusion coefficient and surface exchange reaction rate compared to other known MIEC conductors under the process conditions of interest. Over 10 mumol·cm-2·s-1 (micromoles per square cm per second) of area specific hydrogen flux has been achieved employing a membrane of this material with thickness of 0.2 mm. This flux is several orders of magnitude higher than the hydrogen generation rates reported using other MIEC materials under similar operating conditions.
Separate class true discovery rate degree of association sets for biomarker identification.
Crager, Michael R; Ahmed, Murat
2014-01-01
In 2008, Efron showed that biological features in a high-dimensional study can be divided into classes and a separate false discovery rate (FDR) analysis can be conducted in each class using information from the entire set of features to assess the FDR within each class. We apply this separate class approach to true discovery rate degree of association (TDRDA) set analysis, which is used in clinical-genomic studies to identify sets of biomarkers having strong association with clinical outcome or state while controlling the FDR. Careful choice of classes based on prior information can increase the identification power of the separate class analysis relative to the overall analysis.
National occupant protection use survey : controlled intersection study
DOT National Transportation Integrated Search
1995-05-01
In late 1994, NHTSA conducted the National Occupant Protection Use Survey : (NOPUS). NOPUS is composed of three separate studies: the moving traffic study : which provides information on overall shoulder belt use, the controlled : intersection study ...
A unique measurement technique to study laminar-separation bubble characteristics on an airfoil
NASA Technical Reports Server (NTRS)
Stack, J. P.; Mangalam, S. M.; Berry, S. A.
1987-01-01
A 'nonintrusive', multielement heat-transfer sensor was designed to study laminar-separation bubble characteristics on a NASA LRN (1)-1010 low-Reynolds number airfoil. The sensor consists of 30 individual nickel films, vacuum-deposited on a thin substrate (0.05 mm) that was bonded to the airfoil model with the sensor array placed streamwise on the airfoil upper surface. Experiments were conducted on a 15-cm chord model in the 50,000-300,000 chord Reynolds number range. Time history as well as spectral analysis of signals from surface film gauges were simultaneously obtained to determine the location of laminar separation and the subsequent behavior of the separated shear layer. In addition to the successful determination of laminar separation, a new phenomenon involving a large phase shift in dynamic shear stresses across the separation and reattachment points was observed.
Unsteady Aerodynamic Response of a Linear Cascade of Airfoils in Separated Flow
NASA Technical Reports Server (NTRS)
Capece, Vincent R.; Ford, Christopher; Bone, Christopher; Li, Rui
2004-01-01
The overall objective of this research program was to investigate methods to modify the leading edge separation region, which could lead to an improvement in aeroelastic stability of advanced airfoil designs. The airfoil section used is representative of current low aspect ratio fan blade tip sections. The experimental potion of this study investigated separated zone boundary layer from removal through suction slots. Suction applied to a cavity in the vicinity of the separation onset point was found to be the most effective location. The computational study looked into the influence of front camber on flutter stability. To assess the influence of the change in airfoil shape on stability the work-per-cycle was evaluated for torsion mode oscillations. It was shown that the front camberline shape can be an important factor for stabilizing the predicted work-per-cycle and reducing the predicted extent of the separation zone. In addition, data analysis procedures are discussed for reducing data acquired in experiments that involve periodic unsteady data. This work was conducted in support of experiments being conducted in the NASA Glenn Research Center Transonic Flutter Cascade. The spectral block averaging method is presented. This method is shown to be able to account for variations in airfoil oscillation frequency that can occur in experiments that force oscillate the airfoils to simulate flutter.
NASA Technical Reports Server (NTRS)
Keil, J.
1985-01-01
Wind tunnel tests were conducted on airfoil models in order to study the flow separation phenomena occurring for high angles of attack. Pressure distribution on wings of different geometries were measured. Results show that for three-dimensional airfoils layout and span lift play a role. Separation effects on airfoils with moderate extension are three-dimensional. The flow domains separated from the air foil must be treated three-dimensionally. The rolling-up of separated vortex layers increases with angle in intensity and induction effect and shows strong nonlinearities. Boundary layer material moves perpendicularly to the flow direction due to the pressure gradients at the airfoil; this has a stabilizing effect. The separation starts earlier with increasing pointed profiles.
Experimental, Theoretical, and Computational Investigation of Separated Nozzle Flows
NASA Technical Reports Server (NTRS)
Hunter, Craig A.
2004-01-01
A detailed experimental, theoretical, and computational study of separated nozzle flows has been conducted. Experimental testing was performed at the NASA Langley 16-Foot Transonic Tunnel Complex. As part of a comprehensive static performance investigation, force, moment, and pressure measurements were made and schlieren flow visualization was obtained for a sub-scale, non-axisymmetric, two-dimensional, convergent- divergent nozzle. In addition, two-dimensional numerical simulations were run using the computational fluid dynamics code PAB3D with two-equation turbulence closure and algebraic Reynolds stress modeling. For reference, experimental and computational results were compared with theoretical predictions based on one-dimensional gas dynamics and an approximate integral momentum boundary layer method. Experimental results from this study indicate that off-design overexpanded nozzle flow was dominated by shock induced boundary layer separation, which was divided into two distinct flow regimes; three- dimensional separation with partial reattachment, and fully detached two-dimensional separation. The test nozzle was observed to go through a marked transition in passing from one regime to the other. In all cases, separation provided a significant increase in static thrust efficiency compared to the ideal prediction. Results indicate that with controlled separation, the entire overexpanded range of nozzle performance would be within 10% of the peak thrust efficiency. By offering savings in weight and complexity over a conventional mechanical exhaust system, this may allow a fixed geometry nozzle to cover an entire flight envelope. The computational simulation was in excellent agreement with experimental data over most of the test range, and did a good job of modeling internal flow and thrust performance. An exception occurred at low nozzle pressure ratios, where the two-dimensional computational model was inconsistent with the three-dimensional separation observed in the experiment. In general, the computation captured the physics of the shock boundary layer interaction and shock induced boundary layer separation in the nozzle, though there were some differences in shock structure compared to experiment. Though minor, these differences could be important for studies involving flow control or thrust vectoring of separated nozzles. Combined with other observations, this indicates that more detailed, three-dimensional computational modeling needs to be conducted to more realistically simulate shock-separated nozzle flows.
Zero leakage separable and semipermanent ducting joints
NASA Technical Reports Server (NTRS)
Mischel, H. T.
1973-01-01
A study program has been conducted to explore new methods of achieving zero leakage, separable and semipermanent, ducting joints for space flight vehicles. The study consisted of a search of literature of existing zero leakage methods, the generation of concepts of new methods of achieving the desired zero leakage criteria and the development of detailed analysis and design of a selected concept. Other techniques of leak detection were explored with a view toward improving this area.
Functional Allocation with Airborne Self-Separation Evaluated in a Piloted Simulation
NASA Technical Reports Server (NTRS)
Wing, David J.; Murdoch, Jennifer L.; Chamberlain, James P.; Consiglio, Maria C.; Hoardley, Sherwood T.; Hubbs, Clay E.; Palmer, Michael T.
2010-01-01
A human-in-the-loop simulation experiment was designed and conducted to evaluate an airborne self-separation concept. The activity supports the National Aeronautics and Space Administration s (NASA) research focus on function allocation for separation assurance. The objectives of the experiment were twofold: (1) use experiment design features in common with a companion study of ground-based automated separation assurance to promote comparability, and (2) assess agility of self-separation operations in managing trajectory-changing events in high traffic density, en-route operations with arrival time constraints. This paper describes the experiment and presents initial results associated with subjective workload ratings and group discussion feedback obtained from the experiment s commercial transport pilot participants.
ERIC Educational Resources Information Center
Pfiffner, Linda J.; McBurnett, Keith; Rathouz, Paul J.; Judice, Samuel
2005-01-01
Comorbidities among children with ADHD are key determinants of treatment response, course, and outcome. This study sought to separate family factors (parental psychopathology and parenting practices) associated with comorbid Oppositional Defiant Disorder (ODD) from those associated with Conduct Disorder (CD) among children with Attention…
Manned Mars System Study (MMSS): Mars transportation and facility study. Volume 1: Executive Summary
NASA Technical Reports Server (NTRS)
1990-01-01
The purpose of the study was to design and analyze systems for conducting human missions to Mars and the moon, with special emphasis on the transportation and facility infrastructure. This study was conducted by Martin Marietta Astronautics Group, with an important teaming role by Science Applications International Corporation (SAIC). This work included the studies and separate reports of the FY-1988 and 1989 case studies as well as special analyses and parametric studies.
Xue, Mianqiang; Yan, Guoqing; Li, Jia; Xu, Zhenming
2012-10-02
Electrostatic separation has been widely used to separate conductors and nonconductors for recycling e-waste. However, the components of e-waste are complex, which can be classified as conductors, semiconductors, and nonconductors according to their conducting properties. In this work, we made a novel attempt to recover the mixtures containing conductors (copper), semiconductors (extrinsic silicon), and nonconductors (woven glass reinforced resin) by electrostatic separation. The results of binary mixtures separation show that the separation of conductor and nonconductor, semiconductor and nonconductor need a higher voltage level while the separation of conductor and semiconductor needs a higher roll speed. Furthermore, the semiconductor separation efficiency is more sensitive to the high voltage level and the roll speed than the conductor separation efficiency. An integrated process was proposed for the multiple mixtures separation. The separation efficiency of conductors and semiconductors can reach 82.5% and 88%, respectively. This study contributes to the efficient recycling of valuable resources from e-waste.
Self-doped microphase separated block copolymer electrolyte
Mayes, Anne M.; Sadoway, Donald R.; Banerjee, Pallab; Soo, Philip; Huang, Biying
2002-01-01
A polymer electrolyte includes a self-doped microphase separated block copolymer including at least one ionically conductive block and at least one second block that is immiscible in the ionically conductive block, an anion immobilized on the polymer electrolyte and a cationic species. The ionically conductive block provides a continuous ionically conductive pathway through the electrolyte. The electrolyte may be used as an electrolyte in an electrochemical cell.
Solid state transport-based thermoelectric converter
Hu, Zhiyu
2010-04-13
A solid state thermoelectric converter includes a thermally insulating separator layer, a semiconducting collector and an electron emitter. The electron emitter comprises a metal nanoparticle layer or plurality of metal nanocatalyst particles disposed on one side of said separator layer. A first electrically conductive lead is electrically coupled to the electron emitter. The collector layer is disposed on the other side of the separator layer, wherein the thickness of the separator layer is less than 1 .mu.m. A second conductive lead is electrically coupled to the collector layer.
Chen, Chiao-Chen; Baker, Lane A
2011-01-07
Local conductance variations can be estimated by measuring ion current magnitudes with scanning ion conductance microscopy (SICM). Factors which influence image quality and quantitation of ion currents measured with SICM have been evaluated. Specifically, effects of probe-sample separation and pipette modulation have been systematically studied for the case of imaging conductance variations at pores in a polymer membrane under transmembrane concentration gradients. The influence of probe-sample separation on ion current images was evaluated using distance-modulated (ac) feedback. Approach curves obtained using non-modulated (dc) feedback were also recorded to determine the relative influence of pipette-generated convection by comparison of ion currents measured with both ac and dc feedback modes. To better interpret results obtained, comparison to a model based on a disk-shaped geometry for nanopores in the membrane, as well as relevant position-dependent parameters of the experiment is described. These results advance our current understanding of conductance measurements with SICM.
Solar cell with doped groove regions separated by ridges
Molesa, Steven Edward; Pass, Thomas; Kraft, Steve
2017-01-31
Solar cells with doped groove regions separated by ridges and methods of fabricating solar cells are described. In an example, a solar cell includes a substrate having a surface with a plurality of grooves and ridges. A first doped region of a first conductivity type is disposed in a first of the grooves. A second doped region of a second conductivity type, opposite the first conductivity type, is disposed in a second of the grooves. The first and second grooves are separated by one of the ridges.
Mikulincer, Mario; Dolev, Tamar; Shaver, Phillip R
2004-12-01
The authors conducted 2 studies of attachment-related variations in thought suppression. Participants were asked, or not asked, to suppress thoughts about a relationship breakup and then to perform a Stroop task under high or low cognitive load. The dependent variables were the rebound, of previously suppressed separation-related thoughts (Study 1) and the accessibility of self-traits (Study 2). Under low cognitive load, avoidant individuals did not show any rebound of separation-related thoughts and activated positive self-representations. Under high cognitive load, avoidant participants failed to suppress thoughts of separation and were more likely to activate negative self-representations. Attachment anxiety was associated with high activation of negative self-representations and unremitting separation-related thoughts. The results are discussed in terms of the hidden vulnerabilities of avoidant individuals. ((c) 2004 APA, all rights reserved).
Deformability of shredded tires
DOT National Transportation Integrated Search
1999-01-01
This report describes three separate studies that examine the deformability of shredded tire fill material. The first study determined the response of shredded tires to cyclic loading. These tests were conducted in a load frame on both constrained an...
Molten carbonate fuel cell separator
Nickols, Richard C.
1986-09-02
In a stacked array of molten carbonate fuel cells, a fuel cell separator is positioned between adjacent fuel cells to provide isolation as well as a conductive path therebetween. The center portion of the fuel cell separator includes a generally rectangular, flat, electrical conductor. Around the periphery of the flat portion of the separator are positioned a plurality of elongated resilient flanges which form a gas-tight seal around the edges of the fuel cell. With one elongated flange resiliently engaging a respective edge of the center portion of the separator, the sealing flanges, which are preferably comprised of a noncorrosive material such as an alloy of yttrium, iron, aluminum or chromium, form a tight-fitting wet seal for confining the corrosive elements of the fuel cell therein. This arrangement permits a good conductive material which may be highly subject to corrosion and dissolution to be used in combination with a corrosion-resistant material in the fuel cell separator of a molten carbonate fuel cell for improved fuel cell conductivity and a gas-tight wet seal.
Molten carbonate fuel cell separator
Nickols, R.C.
1984-10-17
In a stacked array of molten carbonate fuel cells, a fuel cell separator is positioned between adjacent fuel cells to provide isolation as well as a conductive path therebetween. The center portion of the fuel cell separator includes a generally rectangular, flat, electrical conductor. Around the periphery of the flat portion of the separator are positioned a plurality of elongated resilient flanges which form a gas-tight seal around the edges of the fuel cell. With one elongated flange resiliently engaging a respective edge of the center portion of the separator, the sealing flanges, which are preferably comprised of a noncorrosive material such as an alloy of yttrium, iron, aluminum or chromium, form a tight-fitting wet seal for confining the corrosive elements of the fuel cell therein. This arrangement permits a good conductive material which may be highly subject to corrosion and dissolution to be used in combination with a corrosion-resistant material in the fuel cell separator of a molten carbonate fuel cell for improved fuel cell conductivity and a gas-tight wet seal.
Stadelmann, Stephanie; Perren, Sonja; Groeben, Maureen; von Klitzing, Kai
2010-03-01
In this longitudinal study, we examine whether the effect of parental separation on kindergarten children's behavioral/emotional problems varies according to the level of family conflict, and children's parental representations. One hundred and eighty seven children were assessed at ages 5 and 6. Family conflict was assessed using parents' ratings. Children's parental representations were assessed using a story-stem task. A multiinformant approach (parent, teacher, child) was employed to assess children's behavioral/emotional problems. Bivariate results showed that separation, family conflict, and negative parental representations were associated with children's behavioral/emotional problems. However, in multivariate analyses, when controlling for gender and symptoms at age 5, we found that children of separated parents who showed negative parental representations had a significantly greater increase in conduct problems between 5 and 6 than all other children. In terms of emotional symptoms and hyperactivity, symptoms at 5 and (for hyperactivity only) gender were the only predictors for symptoms 1 year later. Our results suggest that kindergarten children's representations of parent-child relationships moderate the impact of parental separation on the development of conduct problems, and underline play and narration as a possible route to access the thoughts and feelings of young children faced with parental separation.
Influence of Scientific Stories on Students Ideas about Science and Scientists
ERIC Educational Resources Information Center
Erten, Sinan; Kiray, S. Ahmet; Sen-Gümüs, Betül
2013-01-01
This study was conducted to determine whether a lesson, in which context-based learning approach and scientific stories were used, changed students' (aged 11-12) stereotypical images of science and scientists. Data was collected from two separate sources: Interviews conducted with six students and Draw a Scientist Test (DAST) document that was…
Influence of Scientific Stories on Students Ideas about Science and Scientists
ERIC Educational Resources Information Center
Erten, Sinan; Kiray, S. Ahmet; Sen-Gumus, Betul
2013-01-01
This study was conducted to determine whether a lesson, in which context-based learning approach and scientific stories were used, changed stereotypical images of students (aged 11-12) about science and scientists. Data was collected from two separate sources: Interviews conducted with six students and Draw a Scientist Test (DAST) document that…
Methodological Issues and Practical Problems in Conducting Research on Abused Children.
ERIC Educational Resources Information Center
Kinard, E. Milling
In order to inform policy and programs, research on child abuse must be not only methodologically rigorous, but also practically feasible. However, practical problems make child abuse research difficult to conduct. Definitions of abuse must be explicit and different types of abuse must be assessed separately. Study samples should be as…
Composite mixed oxide ionic and electronic conductors for hydrogen separation
Gopalan, Srikanth [Westborough, MA; Pal, Uday B [Dover, MA; Karthikeyan, Annamalai [Quincy, MA; Hengdong, Cui [Allston, MA
2009-09-15
A mixed ionic and electronic conducting membrane includes a two-phase solid state ceramic composite, wherein the first phase comprises an oxygen ion conductor and the second phase comprises an n-type electronically conductive oxide, wherein the electronically conductive oxide is stable at an oxygen partial pressure as low as 10.sup.-20 atm and has an electronic conductivity of at least 1 S/cm. A hydrogen separation system and related methods using the mixed ionic and electronic conducting membrane are described.
ERIC Educational Resources Information Center
Sola, Agboola Omowunmi; Ojo, Oloyede Ezekiel
2007-01-01
This study assessed and compared the relative effectiveness of three methods for teaching and conducting experiments in separation of mixtures in chemistry. A pre-test, post-test experimental design with a control group was used. Two hundred and thirty three randomly selected Senior Secondary School I (SSS I) chemistry students were drawn from…
NASA Astrophysics Data System (ADS)
Arahman, Nasrul; Maimun, Teuku; Mukramah, Syawaliah
2017-01-01
The composition of polymer solution and the methods of membrane preparation determine the solidification process of membrane. The formation of membrane structure prepared via non-solvent induced phase separation (NIPS) method is mostly determined by phase separation process between polymer, solvent, and non-solvent. This paper discusses the phase separation process of polymer solution containing Polyethersulfone (PES), N-methylpirrolidone (NMP), and surfactant Tetronic 1307 (Tet). Cloud point experiment is conducted to determine the amount of non-solvent needed on induced phase separation. Amount of water required as a non-solvent decreases by the addition of surfactant Tet. Kinetics of phase separation for such system is studied by the light scattering measurement. With the addition of Tet., the delayed phase separation is observed and the structure growth rate decreases. Moreover, the morphology of fabricated membrane from those polymer systems is analyzed by scanning electron microscopy (SEM). The images of both systems show the formation of finger-like macrovoids through the cross-section.
An EEG blind source separation algorithm based on a weak exclusion principle.
Lan Ma; Blu, Thierry; Wang, William S-Y
2016-08-01
The question of how to separate individual brain and non-brain signals, mixed by volume conduction in electroencephalographic (EEG) and other electrophysiological recordings, is a significant problem in contemporary neuroscience. This study proposes and evaluates a novel EEG Blind Source Separation (BSS) algorithm based on a weak exclusion principle (WEP). The chief point in which it differs from most previous EEG BSS algorithms is that the proposed algorithm is not based upon the hypothesis that the sources are statistically independent. Our first step was to investigate algorithm performance on simulated signals which have ground truth. The purpose of this simulation is to illustrate the proposed algorithm's efficacy. The results show that the proposed algorithm has good separation performance. Then, we used the proposed algorithm to separate real EEG signals from a memory study using a revised version of Sternberg Task. The results show that the proposed algorithm can effectively separate the non-brain and brain sources.
Sukholthaman, Pitchayanin; Sharp, Alice
2016-06-01
Municipal solid waste has been considered as one of the most immediate and serious problems confronting urban government in most developing and transitional economies. Providing solid waste performance highly depends on the effectiveness of waste collection and transportation process. Generally, this process involves a large amount of expenditures and has very complex and dynamic operational problems. Source separation has a major impact on effectiveness of waste management system as it causes significant changes in quantity and quality of waste reaching final disposal. To evaluate the impact of effective source separation on waste collection and transportation, this study adopts a decision support tool to comprehend cause-and-effect interactions of different variables in waste management system. A system dynamics model that envisages the relationships of source separation and effectiveness of waste management in Bangkok, Thailand is presented. Influential factors that affect waste separation attitudes are addressed; and the result of change in perception on waste separation is explained. The impacts of different separation rates on effectiveness of provided collection service are compared in six scenarios. 'Scenario 5' gives the most promising opportunities as 40% of residents are willing to conduct organic and recyclable waste separation. The results show that better service of waste collection and transportation, less monthly expense, extended landfill life, and satisfactory efficiency of the provided service at 60.48% will be achieved at the end of the simulation period. Implications of how to get public involved and conducted source separation are proposed. Copyright © 2016 Elsevier Ltd. All rights reserved.
Through-plane conductivities of membranes for nonaqueous redox flow batteries
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, Travis Mark; Small, Leo J.; Pratt, III, Harry D.
In this study, nonaqueous redox flow batteries (RFB) leverage nonaqueous solvents to enable higher operating voltages compared to their aqueous counterparts. Most commercial components for flow batteries, however, are designed for aqueous use. One critical component, the ion-selective membrane, provides ionic conductance between electrodes while preventing crossover of electroactive species. Here we evaluate the area-specific conductances and through-plane conductivities of commercially available microporous separators (Celgard 2400, 2500) and anion exchange membranes (Neosepta AFX, Neosepta AHA, Fumasep FAP-450, Fumasep FAP-PK) soaked in acetonitrile, propylene carbonate, or two imidazolium-based ionic liquids. Fumasep membranes combined with acetonitrile-based electrolyte solutions provided the highest conductancemore » values and conductivities by far. When tested in ionic liquids, all anion exchange membranes displayed conductivities greater than those of the Celgard microporous separators, though the separators’ decreased thickness-enabled conductances on par with the most conductive anion exchange membranes. Ionic conductivity is not the only consideration when choosing an anion exchange membrane; testing of FAP-450 and FAP-PK membranes in a nonaqueous RFB demonstrated that the increased mechanical stability of PEEK-supported FAP-PK minimized swelling, in turn decreasing solvent mediated crossover and enabling greater electrochemical yields (40% vs. 4%) and Coulombic efficiencies (94% vs. 90%) compared to the unsupported, higher conductance FAP-450.« less
Through-plane conductivities of membranes for nonaqueous redox flow batteries
Anderson, Travis Mark; Small, Leo J.; Pratt, III, Harry D.; ...
2015-08-13
In this study, nonaqueous redox flow batteries (RFB) leverage nonaqueous solvents to enable higher operating voltages compared to their aqueous counterparts. Most commercial components for flow batteries, however, are designed for aqueous use. One critical component, the ion-selective membrane, provides ionic conductance between electrodes while preventing crossover of electroactive species. Here we evaluate the area-specific conductances and through-plane conductivities of commercially available microporous separators (Celgard 2400, 2500) and anion exchange membranes (Neosepta AFX, Neosepta AHA, Fumasep FAP-450, Fumasep FAP-PK) soaked in acetonitrile, propylene carbonate, or two imidazolium-based ionic liquids. Fumasep membranes combined with acetonitrile-based electrolyte solutions provided the highest conductancemore » values and conductivities by far. When tested in ionic liquids, all anion exchange membranes displayed conductivities greater than those of the Celgard microporous separators, though the separators’ decreased thickness-enabled conductances on par with the most conductive anion exchange membranes. Ionic conductivity is not the only consideration when choosing an anion exchange membrane; testing of FAP-450 and FAP-PK membranes in a nonaqueous RFB demonstrated that the increased mechanical stability of PEEK-supported FAP-PK minimized swelling, in turn decreasing solvent mediated crossover and enabling greater electrochemical yields (40% vs. 4%) and Coulombic efficiencies (94% vs. 90%) compared to the unsupported, higher conductance FAP-450.« less
Experimental determination of the key heat transfer mechanisms in pharmaceutical freeze-drying.
Ganguly, Arnab; Nail, Steven L; Alexeenko, Alina
2013-05-01
The study is aimed at quantifying the relative contribution of key heat transfer modes in lyophilization. Measurements of vial heat transfer rates in a laboratory-scale freeze-dryer were performed using pure water, which was partially sublimed under various conditions. The separation distance between the shelf and the vial was systematically varied, and sublimation rates were determined gravimetrically. The heat transfer rates were observed to be independent of separation distance between the vial and the shelf and linearly dependent on pressure in the free molecular flow limit, realized at low pressures (<50 mTorr). However, under higher pressures (>120 mTorr), heat transfer rates were independent of pressure and inversely proportional to separation distance. Previous heat transfer studies in conventional freeze-drying cycles have attributed a dominant portion of the total heat transfer to radiation, the rest to conduction, whereas convection has been found to be insignificant. Although the measurements reported here confirm the significance of the radiative and gas conduction components, the convective component has been found to be comparable to the gas conduction contribution at pressures greater than 100 mTorr. The current investigation supports the conclusion that the convective component of the heat transfer cannot be ignored in typical laboratory-scale freeze-drying conditions. Copyright © 2013 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Gwon, Sung-Jin; Choi, Jae-Hak; Sohn, Joon-Yong; An, Sung-Jun; Ihm, Young-Eon; Nho, Young-Chang
2008-08-01
Micro-porous polyethylene separator was modified by radiation grafting of methyl methacrylate in order to improve its affinity with a liquid electrolyte. The degree of grafting (DOG) increased with the monomer concentration and grafting time. The morphological change of the modified separator was investigated by scanning electron microscopy. The degree of crystallinity upon grafting was reduced due to the formation of an amorphous PMMA layer. The electrolyte uptake and the ionic conductivity of the separator increased with an increase in the DOG. The ionic conductivity reached 2.0 mS/cm for the grafted polyethylene separator with 127 wt% DOG.
Separation/divorce and child and adolescent completed suicide.
Gould, M S; Shaffer, D; Fisher, P; Garfinkel, R
1998-02-01
To investigate factors that may modify the effect of separation/divorce on youth suicide. A case-control, psychological autopsy study of 120 of 170 consecutive suicides younger than age 20 and 147 community age-, sex-, and ethnic group-matched controls living in the greater New York area was conducted. Fifty-eight suicide victims and 49 community controls came from nonintact families of origin, indicating the permanent separation/divorce of the biological parents. Potential modifiers of separation/divorce include youth's age at separation, custodial parent's remarriage, nonresidential parent's frequency of contact, parent-child relationships, and parental psychopathology. The relatively small impact of separation/divorce was further diminished after accounting for parental psychopathology. An interaction of separation/divorce and the father-child relationship emerged. The dramatic increase in youth suicide during the past three decades seems unlikely to be attributable to the increase in divorce rates.
Singer, David; Kuhlmann, Julia; Muschket, Matthias; Hoffmann, Ralf
2010-08-01
The separation of isomeric phosphorylated peptides is challenging and often impossible for multiphosphorylated isomers using chromatographic and capillary electrophoretic methods. In this study we investigated the separation of a set of single-, double-, and triple-phosphorylated peptides (corresponding to the human tau protein) by ion-pair reversed-phase chromatography (IP-RPC) and hydrophilic interaction chromatography (HILIC). In HILIC both hydroxyl and aminopropyl stationary phases were tested with aqueous acetonitrile in order to assess their separation efficiency. The hydroxyl phase separated the phosphopeptides very well from the unphosphorylated analogue, while on the aminopropyl phase even isomeric phosphopeptides attained baseline separation. Thus, up to seven phosphorylated versions of a given tau domain were separated. Furthermore, the low concentration of an acidic ammonium formate buffer allowed an online analysis with electrospray ionization tandem mass spectrometry (ESI-MS/MS) to be conducted, enabling peptide sequencing and identification of phosphorylation sites.
Thermal Pretreatment For TRU Waste Sorting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sasaki, T.; Aoyama, Y.; Miyamoto, Y.
2008-07-01
Japan Atomic Energy Agency conducted a study on thermal treatment of TRU waste to develop a removal technology for materials that are forbidden for disposal. The thermal pretreatment in which hot nitrogen and/or air is introduced to the waste is a process of removing combustibles, liquids, and low melting point metals from PVC wrapped TRU waste. In this study, thermal pretreatment of simulated waste was conducted using a desktop thermal treatment vessel and a laboratory scale thermal pretreatment system. Combustibles and low melting point metals are effectively separated from wastes by choosing appropriate temperature of flowing gases. Combustibles such asmore » papers, PVC, oil, etc. were removed and low melting point metals such as zinc, lead, and aluminum were separated from the simulated waste by the thermal pretreatment. (authors)« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seidler, Paul
2011-07-31
Six years of research was conducted for the United States Department of Energy, Office of Nuclear Energy between the years of 2006 through 2011 at the University of Nevada, Las Vegas (UNLV). The results of this research are detailed in the narratives for tasks 1-45. The work performed spanned the range of experimental and modeling efforts. Radiochemistry (separations, waste separation, nuclear fuel, remote sensing, and waste forms) , material fabrication, material characterization, corrosion studies, nuclear criticality, sensors, and modeling comprise the major topics of study during these six years.
NASA Astrophysics Data System (ADS)
Xiong, Bing; Wang, Zhen-Guo; Fan, Xiao-Qiang; Wang, Yi
2017-04-01
To study the characteristics of flow separation and self-excited oscillation of a shock train in a rectangular duct, a simple test case has been conducted and analyzed. The high-speed Schlieren technique and high-frequency pressure measurements have been adopted to collect the data. The experimental results show that there are two separation modes in the duct under M3 incoming condition. The separation mode switch has great effects on the flow effects, such as the pressure distribution, the standard deviation distribution and so on. The separation mode switch can be judged by the history of pressure standard deviation. When it comes to the self-excited oscillation of a shock train, the frequency contents in the undisturbed region, the intermittent region, and the separated bubble have been compared. It was found that the low-frequency disturbance induced by the upstream shock foot motions can travel downstream and the frequency will be magnified by the separation bubble. The oscillation of the small shock foot and the oscillation of the large shock foot are associated with each other rather than oscillating independently.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arges, Christopher G.; Kambe, Yu; Dolejsi, Moshe
Block copolymer electrolytes (BCEs) represent an attractive choice as solid-state ionic conductors for electrochemical technologies used in energy storage and conversion, water treatment, sensors, and data storage and processing. Unlocking the maximum ionic conductivity of BCEs requires an intimate understanding as to how the microphase separated structure influences transport properties. However, elucidating such knowledge remains elusive due to the challenging task of precisely engineering BCEs with a defined structure in bulk materials. In this work, we examined BCEs in a thin film format because it was amenable to attaining BCEs with a desired nanostructure. Specifically, we systematically investigated anion-conducting BCEsmore » with different degrees of connectivity of the ionic domains. For the first time, we demonstrate that increasing terminal defects in the ionic domain from 1 terminal defect per mu m(2) to 20 terminal defects per mu m(2) ( a relatively small amount of defects) decreased ionic conductivity by 67% compared to the maximum value attained. Conversely, maximizing ionic domain connectivity increased the ionic conductivity by two-fold over a non-ordered BCE film. These experiments highlight that microphase separation alone was insufficient for ameliorating ionic conductivity in BCEs. Rather, microphase separation coupled with complete ionic domain connectivity realized BCEs with significantly enhanced ionic conductivity.« less
Sev'er, A
1997-12-01
The link between recent or imminent separation and violence against female partners is discussed. Interviews were conducted among 87 divorced, separated and domestic violence survivors during 1985-88 to study violence perpetrated by men against their female intimate partners. Various bodies of literature are reviewed to establish the fact that separation heightens the risk of violence. The conceptual contributions of social learning and power and control theories are presented as they pertain to intimate violence against women. An expanded version of the power-and-control model is used to underscore the violence proneness of separations, especially when women initiate separations. To illustrate the expanded model, numerous Canadian examples are provided, drawn from interviews with divorced women, survivors of intimate violence, and news media reports. Finally, different strategies to break the cycle of violence are summarized.
Experimental study of supersonic viscous leeside flow over a slender delta wing
NASA Technical Reports Server (NTRS)
Szodruch, J.
1980-01-01
An investigation was conducted to study in detail the vortical flow over the leeward side of a 70 deg swept delta wing having subsonic and supersonic leading edges. Two types of flow were encountered and studied, namely leading edge separation and separation with a shock. Especially for the latter type, Reynolds number plays an important role and unexpected strong streamwise vortices were observed. An optical method is described to obtain a first aproximation of shear stress values in the streamwise direction across the wing span.
Structure and functionality of bromine doped graphite.
Hamdan, Rashid; Kemper, A F; Cao, Chao; Cheng, H P
2013-04-28
First-principles calculations are used to study the enhanced in-plane conductivity observed experimentally in Br-doped graphite, and to study the effect of external stress on the structure and functionality of such systems. The model used in the numerical calculations is that of stage two doped graphite. The band structure near the Fermi surface of the doped systems with different bromine concentrations is compared to that of pure graphite, and the charge transfer between carbon and bromine atoms is analyzed to understand the conductivity change along different high symmetry directions. Our calculations show that, for large interlayer separation between doped graphite layers, bromine is stable in the molecular form (Br2). However, with increased compression (decreased layer-layer separation) Br2 molecules tend to dissociate. While in both forms, bromine is an electron acceptor. The charge exchange between the graphite layers and Br atoms is higher than that with Br2 molecules. Electron transfer to the Br atoms increases the number of hole carriers in the graphite sheets, resulting in an increase of conductivity.
Comparative feasibility study of two concepts for a space-based astrometric satellite
NASA Technical Reports Server (NTRS)
Bamdermann, L.; Bareket, N.; Metheny, W.
1982-01-01
A comparative feasibility study of two concepts for an astrometric satellite: a visual imaging telescope with a 16.5 meter focal length and a white light interferometer with a 15 meter baseline separation was conducted.
NASA Technical Reports Server (NTRS)
Asbury, Scott C.; Hunter, Craig A.
1999-01-01
An investigation was conducted in the model preparation area of the Langley 16-Foot Transonic Tunnel to determine the internal performance of a fixed-geometry exhaust nozzle incorporating porous cavities for shock-boundary layer interaction control. Testing was conducted at static conditions using a sub-scale nozzle model with one baseline and 27 porous configurations. For the porous configurations, the effects of percent open porosity, hole diameter, and cavity depth were determined. All tests were conducted with no external flow at nozzle pressure ratios from 1.25 to approximately 9.50. Results indicate that baseline nozzle performance was dominated by unstable, shock-induced, boundary-layer separation at over-expanded conditions. Porous configurations were capable of controlling off-design separation in the nozzle by either alleviating separation or encouraging stable separation of the exhaust flow. The ability of the porous nozzle concept to alternately alleviate separation or encourage stable separation of exhaust flow through shock-boundary layer interaction control offers tremendous off-design performance benefits for fixed-geometry nozzle installations. In addition, the ability to encourage separation on one divergent flap while alleviating it on the other makes it possible to generate thrust vectoring using a fixed-geometry nozzle.
Environmental factors influencing Pyrenophora semeniperda-caused seed mortality in Bromus tectorum
Heather Finch; Phil S. Allen; Susan E. Meyer
2013-01-01
Temperature and water potential strongly influence seed dormancy status and germination of Bromus tectorum. As seeds of this plant can be killed by the ascomycete fungus Pyrenophora semeniperda, this study was conducted to learn how water potential and temperature influence mortality levels in this pathosystem. Separate experiments were conducted to determine: (1) if P...
Methods for separating a fluid, and devices capable of separating a fluid
TeGrotenhuis, Ward E; Humble, Paul H; Caldwell, Dustin D
2013-05-14
Methods and apparatus for separating fluids are disclosed. We have discovered that, surprisingly, providing an open pore structure between a wick and an open flow channel resulted in superior separation performance. A novel and compact integrated device components for conducting separations are also described.
Modular C3 Interface Analysis (Flexible Intraconnect). Volume 1, Part 1
1980-04-01
was prepared in parallel with a separate Flexible^ Intraconnect design definition study conducted by Hughes Aircraft Company under F19628-77-O-0261...reported herein consists of Task I, Task II, and Task III of Phase I of an on-going study being conducted by the Air Force to develop a Flexible...Intraconnect for tactical C^ tivity. equipment connec- As evidenced by the quantity of analyses performed and docu- mented during the period of this study
NASA Technical Reports Server (NTRS)
Stumpf, R.; Neumann, H. E.; Giamati, C. C.
1983-01-01
An experimental investigation of the time varying distortion at the diffuser exit of a subscale HiMAT forebody and inlet was conducted at Mach 0.9 in the Lewis 8 by 6 foot Supersonic Wind Tunnel. A transitory separation was detected within the subsonic diffuser. Vortex generators were installed to eliminate the flow separation. Results from a study of the instantaneous pressure variations at the diffuser exit are presented. The time unsteady total pressures at the diffuser exit are computer interpolated and presented in the form of a movie showing the transitory separation. Limited data showing the instantaneous distortion levels is also presented.
Chen, Haibin; Yang, Yan; Jiang, Wei; Song, Mengjie; Wang, Ying; Xiang, Tiantian
2017-02-01
A case study on the source separation of municipal solid waste (MSW) was performed in Changsha, the capital city of Hunan Province, China. The objective of this study is to analyze the effects of different separation methods and compare their effects with citizens' attitudes and inclination. An effect evaluation method based on accuracy rate and miscellany rate was proposed to study the performance of different separation methods. A large-scale questionnaire survey was conducted to determine citizens' attitudes and inclination toward source separation. Survey result shows that the vast majority of respondents hold consciously positive attitudes toward participation in source separation. Moreover, the respondents ignore the operability of separation methods and would rather choose the complex separation method involving four or more subclassed categories. For the effects of separation methods, the site experiment result demonstrates that the relatively simple separation method involving two categories (food waste and other waste) achieves the best effect with the highest accuracy rate (83.1%) and the lowest miscellany rate (16.9%) among the proposed experimental alternatives. The outcome reflects the inconsistency between people's environmental awareness and behavior. Such inconsistency and conflict may be attributed to the lack of environmental knowledge. Environmental education is assumed to be a fundamental solution to improve the effect of source separation of MSW in Changsha. Important management tips on source separation, including the reformation of the current pay-as-you-throw (PAYT) system, are presented in this work. A case study on the source separation of municipal solid waste was performed in Changsha. An effect evaluation method based on accuracy rate and miscellany rate was proposed to study the performance of different separation methods. The site experiment result demonstrates that the two-category (food waste and other waste) method achieves the best effect. The inconsistency between people's inclination and the effect of source separation exists. The proposed method can be expanded to other cities to determine the most effective separation method during planning stages or to evaluate the performance of running source separation systems.
Sheathless interface for coupling capillary electrophoresis with mass spectrometry
Wang, Chenchen; Tang, Keqi; Smith, Richard D.
2014-06-17
A sheathless interface for coupling capillary electrophoresis (CE) with mass spectrometry is disclosed. The sheathless interface includes a separation capillary for performing CE separation and an emitter capillary for electrospray ionization. A portion of the emitter capillary is porous or, alternatively, is coated to form an electrically conductive surface. A section of the emitter capillary is disposed within the separation capillary, forming a joint. A metal tube, containing a conductive liquid, encloses the joint.
Wu, Jiang; Li, Jia; Xu, Zhenming
2009-08-15
Electrostatic separation presents an effective and environmentally friendly way for recycling metals and nonmetals from ground waste electrical and electronic equipment (WEEE). For this process, the trajectory of conductive particle is significant and some models have been established. However, the results of previous researches are limited by some simplifying assumptions and lead to a notable discrepancy between the model prediction and the experimental results. In the present research, a roll-type corona-electrostatic separator and ground printed circuit board (PCB) wastes were used to investigate the trajectory of the conductive particle. Two factors, the air drag force and the different charging situation, were introduced into the improved model. Their effects were analyzed and an improved model for the theoretical trajectory of conductive particle was established. Compared with the previous one, the improved model shows a good agreement with the experimental results. It provides a positive guidance for designing of separator and makes a progress for recycling the metals and nonmetals from WEEE.
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. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Maity, Sudhangshu; Jana, Tushar
2014-05-14
A series of meta-polybenzimidazole-block-para-polybenzimidazole (m-PBI-b-p-PBI), segmented block copolymers of PBI, were synthesized with various structural motifs and block lengths by condensing the diamine terminated meta-PBI (m-PBI-Am) and acid terminated para-PBI (p-PBI-Ac) oligomers. NMR studies and existence of two distinct glass transition temperatures (Tg), obtained from dynamical mechanical analysis (DMA) results, unequivocally confirmed the formation of block copolymer structure through the current polymerization methodology. Appropriate and careful selection of oligomers chain length enabled us to tailor the block length of block copolymers and also to make varieties of structural motifs. Increasingly distinct Tg peaks with higher block length of segmented block structure attributed the decrease in phase mixing between the meta-PBI and para-PBI blocks, which in turn resulted into nanophase segregated domains. The proton conductivities of proton exchange membrane (PEM) developed from phosphoric acid (PA) doped block copolymer membranes were found to be increasing substantially with increasing block length of copolymers even though PA loading of these membranes did not alter appreciably with varying block length. For example when molecular weight (Mn) of blocks were increased from 1000 to 5500 then the proton conductivities at 160 °C of resulting copolymers increased from 0.05 to 0.11 S/cm. Higher block length induced nanophase separation between the blocks by creating less morphological barrier within the block which facilitated the movement of the proton in the block and hence resulting higher proton conductivity of the PEM. The structural varieties also influenced the phase separation and proton conductivity. In comparison to meta-para random copolymers reported earlier, the current meta-para segmented block copolymers were found to be more suitable for PBI-based PEM.
Separation from supported employment: a retrospective chart review study.
West, Michael; Targett, Pamela; Wehman, Paul; Cifu, Gabriella; Davis, Jacob
2015-01-01
The objective of this study was to examine job separations from supported employment (SE). The aim was to identify the types and nature of separations and precipitating events leading to the separation. A retrospective chart review methodology was utilized. The study was conducted in a metropolitan area in the Southeast United States by a university-based SE program. Participants were 47 SE clients who had been placed into and separated from 67 jobs. Using a coding form, information regarding the type of separation and issues that preceded the separation were recorded. Data were aggregated using descriptive statistics. The largest number of separations was due to termination, followed by resignation and mutual consent of the employer and employee. The mean number of issues leading to the separation was 2.2, ranging from one to five. Only eight positive issues were found (compared to 116 negative and 20 neutral), the most prevalent being entry into an educational or training program. Common negative issues included poor work performance, attendance and punctuality problems, conflicts with the supervisor, and social and behavioral issues. The findings of this study illustrate the need to address job retention issues during the job development process, finding the most appropriate person-job fit and workplace culture for each client. The findings also support the need for vigilant and regular communication between the SE program and employers to intervene quickly when problems arise. Separation from Supported Employment (SE) SE is an evidence-based employment practice that has been shown effective across multiple disability groups. Studying job separations can provide valuable information for improving service. Locating the best person-job fit, as well as frequent contract with employers, can help prevent unnecessary job loss.
Contactless conductivity detector for microchip capillary electrophoresis
NASA Technical Reports Server (NTRS)
Pumera, Martin; Wang, Joseph; Opekar, Frantisek; Jelinek, Ivan; Feldman, Jason; Lowe, Holger; Hardt, Steffen; Svehla, D. (Principal Investigator)
2002-01-01
A microfabricated electrophoresis chip with an integrated contactless conductivity detection system is described. The new contactless conductivity microchip detector is based on placing two planar sensing aluminum film electrodes on the outer side of a poly(methyl methacrylate) (PMMA) microchip (without contacting the solution) and measuring the impedance of the solution in the separation channel. The contactless route obviates problems (e.g., fouling, unwanted reactions) associated with the electrode-solution contact, offers isolation of the detection system from high separation fields, does not compromise the separation efficiency, and greatly simplifies the detector fabrication. Relevant experimental variables, such as the frequency and amplitude of the applied ac voltage or the separation voltage, were examined and optimized. The detector performance was illustrated by the separation of potassium, sodium, barium, and lithium cations and the chloride, sulfate, fluoride, acetate, and phosphate anions. The response was linear (over the 20 microM-7 mM range) and reproducible (RSD = 3.4-4.9%; n = 10), with detection limits of 2.8 and 6.4 microM (for potassium and chloride, respectively). The advantages associated with the contactless conductivity detection, along with the low cost of the integrated PMMA chip/detection system, should enhance the power and scope of microfluidic analytical devices.
Holness, Howard K; Jamal, Adeel; Mebel, Alexander; Almirall, José R
2012-11-01
A new mechanism is proposed that describes the gas-phase separation of chiral molecules found in amphetamine-type substances (ATS) by the use of high-resolution ion mobility spectrometry (IMS). Straight-chain achiral alcohols of increasing carbon chain length, from methanol to n-octanol, are used as drift gas modifiers in IMS to highlight the mechanism proposed for gas-phase separations of these chiral molecules. The results suggest the possibility of using these achiral modifiers to separate the chiral molecules (R,S) and (S,R)-ephedrine and (S,S) and (R,R)-pseudoephedrine which contain an internal hydroxyl group at the first chiral center and an amino group at the other chiral center. Ionization was achieved with an electrospray source, the ions were introduced into an IMS with a resolving power of 80, and the resulting ion clusters were characterized with a coupled quadrupole mass spectrometer detector. A complementary computational study conducted at the density functional B3LYP/6-31g level of theory for the electronic structure of the analyte-modifier clusters was also performed, and showed either "bridged" or "independent" binding. The combined experimental and simulation data support the proposed mechanism for gas-phase chiral separations using achiral modifiers in the gas phase, thus enhancing the potential to conduct fast chiral separations with relative ease and efficiency.
Bohn, Justin; Eddings, Wesley; Schneeweiss, Sebastian
2017-03-15
Distributed networks of health-care data sources are increasingly being utilized to conduct pharmacoepidemiologic database studies. Such networks may contain data that are not physically pooled but instead are distributed horizontally (separate patients within each data source) or vertically (separate measures within each data source) in order to preserve patient privacy. While multivariable methods for the analysis of horizontally distributed data are frequently employed, few practical approaches have been put forth to deal with vertically distributed health-care databases. In this paper, we propose 2 propensity score-based approaches to vertically distributed data analysis and test their performance using 5 example studies. We found that these approaches produced point estimates close to what could be achieved without partitioning. We further found a performance benefit (i.e., lower mean squared error) for sequentially passing a propensity score through each data domain (called the "sequential approach") as compared with fitting separate domain-specific propensity scores (called the "parallel approach"). These results were validated in a small simulation study. This proof-of-concept study suggests a new multivariable analysis approach to vertically distributed health-care databases that is practical, preserves patient privacy, and warrants further investigation for use in clinical research applications that rely on health-care databases. © The Author 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
PROCESS IMPROVEMENT STUDIES ON THE BATTELLE HYDROTHERMAL COAL PROCESS
The report gives results of a study to improve the economic viability of the Battelle Hydrothermal (HT) Coal Process by reducing the costs associated with liquid/solid separation and leachant regeneration. Laboratory experiments were conducted to evaluate process improvements for...
NASA Technical Reports Server (NTRS)
Williams, G., Jr.
1983-01-01
The continuous flow electrophoresis system makes electrophoresis possible in a free flowing film of aqueous electrolyte medium. The sample is introduced at one end of the chamber and is subjected to a lateral dc field. This process separates the sample into fractions since each component has a distinctive electrophoric mobility. Evaluations were made of sample conductivity and buffer conductivity as they affect sample band spread and separation using the Continuous Particle Electrophoresis (CPE) system. Samples were prepared from mixtures of 5 percent and 1 percent polystyrene latex (PSL) microspheres which were .4, .56 and .7 microns in diameter. These were prepared in electrolyte media 1x and 3x the conductivity of the curtain buffer, approximately 150 and 450 micro mhos/cm. Samples with matched conductivities produced greater resolution and less band spread than those with 3x the conductivity of the curtain buffer.
ERIC Educational Resources Information Center
Seppanen, Loretta
In 1991, the Washington State Board for Community College Education conducted a study to determine the strengths and shortcomings of Washington community colleges' efforts to provide upgrading and retraining for employed workers. Data were derived from four separate studies conducted in 1990, including a survey of 1,151 employed students at eight…
ERIC Educational Resources Information Center
GROPPER, GEORGE L.; LUMSDAINE, ARTHUR A.
A SERIES OF EXPERIMENTS WAS CONDUCTED TO TEST THE EFFECTIVENESS OF TELEVISED INSTRUCTION. THIS STUDY, THE THIRD IN A SERIES, EXPLORED THE ROLE IN FIXED-PACE TELEVISION INSTRUCTION OF SOME OF THE TECHNIQUES AND PRACTICES EMPLOYED IN TEACHING-MACHINE INSTRUCTION. THREE SEPARATE EXPERIMENTS WERE CONDUCTED--(1) A JUNIOR HIGH SCHOOL LESSON ON NEWTON'S…
Separation control by vortex generator devices in a transonic channel flow
NASA Astrophysics Data System (ADS)
Bur, Reynald; Coponet, Didier; Carpels, Yves
2009-12-01
An experimental study was conducted in a transonic channel to control by mechanical vortex generator devices the strong interaction between a shock wave and a separated turbulent boundary layer. Control devices—co-rotating and counter-rotating vane-type vortex generators—were implemented upstream of the shock foot region and tested both on a steady shock wave and on a forced shock oscillation configurations. The spanwise spacing of vortex generator devices along the channel appeared to be an important parameter to control the flow separation region. When the distance between each device is decreased, the vortices merging is more efficient to reduce the separation. Their placement upstream of the shock wave is determinant to ensure that vortices have mixed momentum all spanwise long before they reach the separation line, so as to avoid separation cells. Then, vortex generators slightly reduced the amplitude of the forced shock wave oscillation by delaying the upstream displacement of the leading shock.
NASA Technical Reports Server (NTRS)
Daryabeigi, Kamran; Walker, Sandra P.
2009-01-01
The objective of the present study was to determine whether infrared imaging (IR) surface temperature data obtained during arc-jet tests of Space Shuttle Orbiter s reinforced carbon-carbon (RCC) wing leading edge panel slip-side joggle region could be used to detect presence of subsurface material separation, and if so, to determine when separation occurs during the simulated entry profile. Recent thermostructural studies have indicated thermally induced interlaminar normal stress concentrations at the substrate/coating interface in the curved joggle region can result in local subsurface material separation, with the separation predicted to occur during approach to peak heating during reentry. The present study was an attempt to determine experimentally when subsurface material separations occur. A simplified thermal model of a flat RCC panel with subsurface material separation was developed and used to infer general surface temperature trends due to the presence of subsurface material separation. IR data from previously conducted arc-jet tests on three test specimens were analyzed: one without subsurface material separation either pre or post test, one with pre test separation, and one with separation developing during test. The simplified thermal model trend predictions along with comparison of experimental IR data of the three test specimens were used to successfully infer material separation from the arc-jet test data. Furthermore, for the test specimen that had developed subsurface material separation during the arc-jet tests, the initiation of separation appeared to occur during the ramp up to the peak heating condition, where test specimen temperature went from 2500 to 2800 F.
Reliability of excess-flow check-valves in turbine lubrication systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dundas, R.E.
1996-12-31
Reliability studies on excess-flow check valves installed in a gas turbine lubrication system for prevention of spray fires subsequent to fracture or separation of lube lines were conducted. Fault-tree analyses are presented for the case of failure of a valve to close when called upon by separation of a downstream line, as well as for the case of accidental closure during normal operation, leading to interruption of lubricating oil flow to a bearing. The probabilities of either of these occurrences are evaluated. The results of a statistical analysis of accidental closure of excess-flow check valves in commercial airplanes in themore » period 1986--91 are also given, as well as a summary of reliability studies on the use of these valves in residential gas installations, conducted under the sponsorship of the Gas Research Institute.« less
Walker, Paul; Kelley, Tim
2003-11-01
Increased swine production results in concentration of wastes generated within a limited geographical area, which may lead to land application rates exceeding the local or regional assimilatory capacity. This may result in pollutant transfer through surface water or soil-groundwater systems, environmental degradation, and/or odor concerns. Existing swine waste pit storage and lagoon treatment technologies may be inadequate to store or treat waste prior to land application without these concerns resulting. Efficient swine waste solids separation may reduce environmental health concerns and generate a value-added bioresource (solids). This study evaluated the efficiency of a polyacrylamide (PAM) flocculant-aided solids separation treatment to reduce pollution indicator concentrations in raw (untreated) swine waste slurry. Swine waste slurry solids separation efficiency through gravity settling (sedimentation) was evaluated before and after the addition of a proprietary polymeric (PAM) flocculant. Results indicated that polymer amendments at concentrations of 62.5-750 mg/l improved slurry solids separation efficiency and significantly reduced concentrations of other associated aquatic pollution indicators in a majority of analyses conducted (33 of 50 total analyses conducted). Results also suggested that PAM-aided solids separation from swine waste slurry might facilitate further treatment and/or disposal and therefore reduce associated environmental degradation potential.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sasaki, Takayuki, E-mail: sasaki@nucleng.kyoto-u.ac.jp; Rajib, Mohammad; Akiyoshi, Masafumi
2015-06-15
The present study reports the likely first attempt of separating radioactive minerals for estimation of activity concentration in the beach placer sands of Bangladesh. Several sand samples from heavy mineral deposits located at the south-eastern coastal belt of Bangladesh were processed to physically upgrade their radioactivity concentrations using plant and laboratory equipment. Following some modified flow procedure, individual fractions were separated and investigated using gamma-ray spectrometry and powder-XRD analysis. The radioactivity measurements indicated contributions of the thorium and uranium radioactive series and of {sup 40}K. The maximum values of {sup 232}Th and {sup 238}U, estimated from the radioactivity of {supmore » 208}Tl and {sup 234}Th in secular equilibrium, were found to be 152,000 and 63,300 Bq/kg, respectively. The fraction of the moderately conductive part in electric separation contained thorium predominantly, while that of the non-conductive part was found to be uranium rich. The present arrangement of the pilot plant cascade and the fine tuning of setting parameters were found to be effective and economic separation process of the radioactive minerals from placer sands in Bangladesh. Probable radiological impacts and extraction potentiality of such radioactive materials are also discussed.« less
ERIC Educational Resources Information Center
Shelton, Katherine H.; Harold, Gordon T.; Fowler, Tom A.; Rice, Frances J.; Neale, Michael C.; Thapar, Anita; van den Bree, Marianne B. M.
2008-01-01
This study investigated genetic and environmental influences on the associations between mother-child relationship quality (warmth and hostility) and adolescent conduct problems and cigarette use. Participants included 601 mothers and adolescent twin pairs (aged 12-17 years). Mothers and adolescents provided separate reports of mother-to-child…
5 CFR 3501.102 - Designation of separate agency components.
Code of Federal Regulations, 2010 CFR
2010-01-01
... ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF THE INTERIOR § 3501.102 Designation of separate agency...: A company that conducts activities regulated by the Bureau of Land Management would not be a prohibited source of gifts for an employee of the National Park Service (NPS), unless that company seeks...
Electrochemical Cell with Improved Water or Gas Management
NASA Technical Reports Server (NTRS)
LaGrange, Jay W. (Inventor); Smith, William F. (Inventor); McElroy, James F. (Inventor)
2015-01-01
An electrochemical cell having a water/gas porous separator prepared from a polymeric material and one or more conductive cell components that pass through, or are located in close proximity to, the water/gas porous separator, is provided. The inventive cell provides a high level of in-cell electrical conductivity.
The Impact of Prior Deployment Experience on Civilian Employment After Military Service
2013-03-21
covariates men- tioned. Given the exploratory nature of this study, all defined variables were included. Model diagnostic tests were conducted and we...assessed model fit using the Hosmer–Lemeshow goodness-of-fit test . To identify the existence of collinearity, we examined all variance inflation factors...separation, and reason for separation and service branch were tested . Both interactions were significant at pɘ.10. Three models were built to examine
5 CFR 3601.102 - Designation of separate agency components.
Code of Federal Regulations, 2012 CFR
2012-01-01
... ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF DEFENSE § 3601.102 Designation of separate agency... Services University of the Health Sciences. (b) Employees of DoD components not designated as separate...
5 CFR 3601.102 - Designation of separate agency components.
Code of Federal Regulations, 2013 CFR
2013-01-01
... ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF DEFENSE § 3601.102 Designation of separate agency... Services University of the Health Sciences. (b) Employees of DoD components not designated as separate...
5 CFR 3601.102 - Designation of separate agency components.
Code of Federal Regulations, 2014 CFR
2014-01-01
... ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF DEFENSE § 3601.102 Designation of separate agency... Services University of the Health Sciences. (b) Employees of DoD components not designated as separate...
Perceptions of Teacher Candidates about Social Network Usage Levels in Turkey
ERIC Educational Resources Information Center
Koçoglu, Erol
2017-01-01
This study was conducted to determine the perceptions of the teacher candidates in educational faculties in Turkey about social network usage levels in today's globalizing world. The study was performed with 4 separate study groups. The first study group consisted of 657 teacher candidates, the second study group consisted of 364 teacher…
Electrically Conductive Porous Membrane
NASA Technical Reports Server (NTRS)
Burke, Kenneth Alan (Inventor)
2014-01-01
The present invention relates to an electrically conductive membrane that can be configured to be used in fuel cell systems to act as a hydrophilic water separator internal to the fuel cell, or as a water separator used with water vapor fed electrolysis cells, or as a water separator used with water vapor fed electrolysis cells, or as a capillary structure in a thin head pipe evaporator, or as a hydrophobic gas diffusion layer covering the fuel cell electrode surface in a fuel cell.
Persistent mobility edges and anomalous quantum diffusion in order-disorder separated quantum films
NASA Astrophysics Data System (ADS)
Zhong, Jianxin; Stocks, G. Malcolm
2007-01-01
A concept of order-disorder separated quantum films is proposed for the design of ultrathin quantum films of a few atomic layers thick with unconventional transport properties. The concept is demonstrated through studying an atomic bilayer comprised of an ordered layer and a disordered layer. Without the disordered layer or the ordered layer, the system is a conducting two-dimensional (2D) crystal or an insulating disordered 2D electron system. Without the order-disorder phase separation, a disordered bilayer is insulating under large disorder. In an order-disorder separated atomic bilayer, however, we show that the system behaves remarkably different from conventional ordered or disordered electron systems, exhibiting metal-insulator transitions with persistent mobility edges and superdiffusive anomalous quantum diffusion.
Sugimura, Kazumi; Crocetti, Elisabetta; Hatano, Kai; Kaniušonytė, Goda; Hihara, Shogo; Žukauskienė, Rita
2018-04-01
Emotional separation and parental trust in parent-adolescent relationships are important factors for adolescent identity formation. However, prior research findings on emotional separation are inconsistent. This study aimed to conduct a more rigorous examination of the associations of emotional separation and parental trust with identity synthesis, confusion, and consolidation by applying a bi-factor model to identity, using adolescent samples from Lithuania (N = 610; 53.9% female; M age = 14.92), Italy (N = 411; 57.4% female; M age = 15.03), and Japan (N = 759; 43.7% female; M age = 14.13). Structural equation modeling revealed that emotional separation and parental trust were consistently associated with identity consolidation across the three countries, rather than associated with identity synthesis and identity confusion. Furthermore, the patterns of associations of emotional separation and parental trust with identity synthesis and identity confusion differed across the three nations. Overall, this study provides a better understanding of the role of emotional separation and parental trust in adolescent identity formation by suggesting the importance of the identity consolidation in the association between parent-child relationships and identity formation across three countries.
Yeo, Jun-Seok; Yun, Jin-Mun; Kim, Dong-Yu; Park, Sungjun; Kim, Seok-Soon; Yoon, Myung-Han; Kim, Tae-Wook; Na, Seok-In
2012-05-01
In the present study, a novel polar-solvent vapor annealing (PSVA) was used to induce a significant structural rearrangement in poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films in order to improve their electrical conductivity and work function. The effects of polar-solvent vapor annealing on PEDOT:PSS were systematically compared with those of a conventional solvent additive method (SAM) and investigated in detail by analyzing the changes in conductivity, morphology, top and bottom surface composition, conformational PEDOT chains, and work function. The results confirmed that PSVA induces significant phase separation between excess PSS and PEDOT chains and a spontaneous formation of a highly enriched PSS layer on the top surface of the PEDOT:PSS polymer blend, which in turn leads to better 3-dimensional connections between the conducting PEDOT chains and higher work function. The resultant PSVA-treated PEDOT:PSS anode films exhibited a significantly enhanced conductivity of up to 1057 S cm(-1) and a tunable high work function of up to 5.35 eV. The PSVA-treated PEDOT:PSS films were employed as transparent anodes in polymer light-emitting diodes (PLEDs) and polymer solar cells (PSCs). The cell performances of organic optoelectronic devices with the PSVA-treated PEDOT:PSS anodes were further improved due to the significant vertical phase separation and the self-organized PSS top surface in PSVA-treated PEDOT:PSS films, which can increase the anode conductivity and work function and allow the direct formation of a functional buffer layer between the active layer and the polymeric electrode. The results of the present study will allow better use and understanding of polymeric-blend materials and will further advance the realization of high-performance indium tin oxide (ITO)-free organic electronics.
Wang, Sheng-ye; Tang, Yan-kui; Li, Kun; Mo, Ya-yuan; Li, Hao-feng; Gu, Zhan-qi
2014-12-01
Magnetic biochar was prepared with eucalyptus leaf residue remained after essential oil being extracted. Batch experiments were conducted to examine the capacity of the magnetic biochar to remove Cr (VI) from electroplating wastewater and to be separated by an external magnetic field. The results show that the initial solution pH plays an important role on both sorption and separation. The removal rates of Cr (VI), total Cr, Cu (II), and Ni (II) were 97.11%, 97.63%, 100% and 100%, respectively. The turbidity of the sorption-treated solution was reduced to 21.8NTU from 4075NTU after 10min magnetic separation. The study also confirms that the magnetic biochar still retains the original magnetic separation performance after the sorption process. Copyright © 2014 Elsevier Ltd. All rights reserved.
(PRESENTED NAQC SAN FRANCISCO, CA) COARSE PM METHODS STUDY: STUDY DESIGN AND RESULTS
Comprehensive field studies were conducted to evaluate the performance of sampling methods for measuring the coarse fraction of PM10 in ambient air. Five separate sampling approaches were evaluated at each of three sampling sites. As the primary basis of comparison, a discrete ...
Cell separator for use in bipolar-stack energy storage devices
Mayer, Steven T.; Feikert, John H.; Kachmitter, James L.; Pekala, Richard W.
1995-01-01
An improved multi-cell electrochemical energy storage device, such as a battery, fuel cell, or double layer capacitor using a cell separator which allows cells to be stacked and interconnected with low electrical resistance and high reliability while maximizing packaging efficiency. By adding repeating cells, higher voltages can be obtained. The cell separator is formed by applying an organic adhesive on opposing surfaces of adjacent carbon electrodes or surfaces of aerogel electrodes of a pair of adjacent cells prior to or after pyrolysis thereof to form carbon aerogel electrodes. The cell separator is electronically conductive, but ionically isolating, preventing an electrolytic conduction path between adjacent cells in the stack.
NASA Technical Reports Server (NTRS)
Costa, Guillermo J.; Arteaga, Ricardo A.
2011-01-01
A preliminary survey of existing separation assurance and collision avoidance advancements, technologies, and efforts has been conducted in order to develop a concept of operations for flight testing autonomous separation assurance at Dryden Flight Research Center. This effort was part of the Unmanned Aerial Systems in the National Airspace System project. The survey focused primarily on separation assurance projects validated through flight testing (including lessons learned), however current forays into the field were also examined. Comparisons between current Dryden flight and range assets were conducted using House of Quality matrices in order to allow project management to make determinations regarding asset utilization for future flight tests. This was conducted in order to establish a body of knowledge of the current collision avoidance landscape, and thus focus Dryden s efforts more effectively towards the providing of assets and test ranges for future flight testing within this research field.
Gerald, II, Rex E; Ruscic, Katarina J; Sears, Devin N; Smith, Luis J; Klinger, Robert J; Rathke, Jerome W
2013-11-26
The invention relates to a unique battery having a physicochemically active membrane separator/electrolyte-electrode monolith and method of making the same. The Applicant's invented battery employs a physicochemically active membrane separator/electrolyte-electrode that acts as a separator, electrolyte, and electrode, within the same monolithic structure. The chemical composition, physical arrangement of molecules, and physical geometry of the pores play a role in the sequestration and conduction of ions. In one preferred embodiment, ions are transported via the ion-hoping mechanism where the oxygens of the Al.sub.2O.sub.3 wall are available for positive ion coordination (i.e. Li.sup.+). This active membrane-electrode composite can be adjusted to a desired level of ion conductivity by manipulating the chemical composition and structure of the pore wall to either increase or decrease ion conduction.
Gerald II, Rex E.; Ruscic, Katarina J.; Sears, Devin N.; Smith, Luis J.; Klingler, Robert J.; Rathke, Jerome W.
2012-07-24
The invention relates to a unique battery having a physicochemically active membrane separator/electrolyte-electrode monolith and method of making the same. The Applicant's invented battery employs a physicochemically active membrane separator/electrolyte-electrode that acts as a separator, electrolyte, and electrode, within the same monolithic structure. The chemical composition, physical arrangement of molecules, and physical geometry of the pores play a role in the sequestration and conduction of ions. In one preferred embodiment, ions are transported via the ion-hoping mechanism where the oxygens of the Al2O3 wall are available for positive ion coordination (i.e. Li+). This active membrane-electrode composite can be adjusted to a desired level of ion conductivity by manipulating the chemical composition and structure of the pore wall to either increase or decrease ion conduction.
Johnson, Monique E; Montoro Bustos, Antonio R; Winchester, Michael R
2016-11-01
Single particle inductively coupled plasma mass spectrometry (spICP-MS) is shown to be a practical technique to study the efficacy of rate-zonal sucrose density gradient centrifugation (SDGC) separations of mixtures of gold nanoparticles (AuNPs) in liquid suspension. spICP-MS enabled measurements of AuNP size distributions and particle number concentrations along the gradient, allowing unambiguous evaluations of the effectiveness of the separation. Importantly, these studies were conducted using AuNP concentrations that are directly relevant to environmental studies (sub ng mL -1 ). At such low concentrations, other techniques [e.g., dynamic light scattering (DLS), transmission and scanning electron microscopies (TEM and SEM), UV-vis spectroscopy, atomic force microscopy (AFM)] do not have adequate sensitivity, highlighting the inherent value of spICP-MS for this and similar applications. In terms of the SDGC separations, a mixture containing three populations of AuNPs, having mean diameters of 30, 80, and 150 nm, was fully separated, while separations of two other mixtures (30, 60, 100 nm; and 20, 50, 100 nm) were less successful. Finally, it is shown that the separation capacity of SDGC can be overwhelmed when particle number concentrations are excessive, an especially relevant finding in view of common methodologies taken in nanotechnology research. Graphical Abstract Characterization of the separation of a gold nanoparticle mixture by sucrose density gradient centrifugation by conventional and single particle ICP-MS analysis.
Vermicomposting of source-separated human faeces for nutrient recycling.
Yadav, Kunwar D; Tare, Vinod; Ahammed, M Mansoor
2010-01-01
The present study examined the suitability of vermicomposting technology for processing source-separated human faeces. Since the earthworm species Eisenia fetida could not survive in fresh faeces, modification in the physical characteristics of faeces was necessary before earthworms could be introduced to faeces. A preliminary study with six different combinations of faeces, soil and bulking material (vermicompost) in different layers was conducted to find out the best condition for biomass growth and reproduction of earthworms. The results indicated that SVFV combination (soil, vermicompost, faeces and vermicompost - bottom to top layers) was the best for earthworm biomass growth indicating the positive role of soil layer in earthworm biomass growth. Further studies with SVFV and VFV combinations, however, showed that soil layer did not enhance vermicompost production rate. Year-long study conducted with VFV combination to assess the quality and quantity of vermicompost produced showed an average vermicompost production rate of 0.30kg-cast/kg-worm/day. The vermicompost produced was mature as indicated by low dissolved organic carbon (2.4+/-0.43mg/g) and low oxygen uptake rate (0.15+/-0.09mg O(2)/g VS/h). Complete inactivation of total coliforms was noted during the study, which is one of the important objectives of human faeces processing. Results of the study thus indicated the potential of vermicomposting for processing of source-separated human faeces.
Age 60 study, part II : airline pilot age and performance - a review of the scientific literature.
DOT National Transportation Integrated Search
1994-10-01
This review of the literature establishes the scientific foundation for subsequent studies on the Age 60 Rule research conducted under a contract with Hilton Systems, Inc. The scientific literature relevant to the two separate scientific approaches r...
Near-field excitation exchange between motionless point atoms located near the conductive surface
NASA Astrophysics Data System (ADS)
Kuraptsev, Aleksei S.; Sokolov, Igor M.
2018-04-01
On the basis of quantum microscopic approach we study the excitation dynamics of two motionless point atoms located near the perfectly conducting mirror. We have analyzed the spontaneous decay rate of individual atoms near the mirror as well as the strength of dipole-dipole interaction between different atoms. It is shown that the spontaneous decay rate of an excited atom significantly depends on the distance from this atom to the mirror. In the case when the interatomic separation is less or comparable with the wavelength of resonant radiation, the spontaneous decay dynamics of an excited atom is described by multi-exponential law. It depends both the interatomic separation and the spatial orientation of diatomic quasimolecule.
Oláh, Erzsébet; Fekete, Szabolcs; Fekete, Jeno; Ganzler, Katalin
2010-06-04
Today sub-2 microm packed columns are very popular to conduct fast chromatographic separations. The mass-transfer resistance depends on the particle size but some practical limits exist not to reach the theoretically expected plate height and mass-transfer resistance. Another approach applies particles with shortened diffusion path to enhance the efficiency of separations. In this study a systematical evaluation of the possibilities of the separations obtained with 5 cm long narrow bore columns packed with new 2.6 microm shell particles (1.9 microm nonporous core surrounded by a 0.35 microm porous shell, Kinetex, Core-Shell), packed with other shell-type particles (Ascentis Express, Fused-Core), totally porous sub-2 microm particles and a 5 cm long narrow bore monolith column is presented. The different commercially available columns were compared by using van Deemter, Knox and kinetic plots. Theoretical Poppe plots were constructed for each column to compare their kinetic performance. Data are presented on polar neutral real-life analytes. Comparison of a low molecular weight compounds (MW=270-430) and a high molecular weight one (MW approximately 900) was conducted. This study proves that the Kinetex column packed with 2.6 microm shell particles is worthy of rivaling to sub-2 microm columns and other commercially available shell-type packings (Ascentis Express or Halo), both for small and large molecule separation. The Kinetex column offers a very flat C term. Utilizing this feature, high flow rates can be applied to accomplish very fast separations without significant loss in efficiency. Copyright 2010 Elsevier B.V. All rights reserved.
Onuki, Yoshinori; Funatani, Chiaki; Yamamoto, Yoshihisa; Fukami, Toshiro; Koide, Tatsuo; Hayashi, Yoshihiro; Takayama, Kozo
2017-01-01
A moisturizing cream mixed with a steroid ointment is frequently prescribed to patients suffering from atopic dermatitis. However, there is a concern that the mixing operation causes destabilization. The present study was performed to investigate the stability of such preparations closely using magnetic resonance imaging (MRI). As sample preparations, five commercial moisturizing creams that are popular in Japan were mixed with an ointment base, a white petrolatum, at a volume ratio of 1 : 1. The mixed preparations were stored at 60°C to accelerate the destabilization processes. Subsequently, the phase separations induced by the storage test were monitored using MRI. Using advanced MR technologies including spin-spin relaxation time (T 2 ) mapping and MR spectroscopy, we successfully characterized the phase-separation behavior of the test samples. For most samples, phase separations developed by the bleeding of liquid oil components. From a sample consisting of an oil-in-water-type cream, Urepearl Cream 10%, a distinct phase-separation mode was observed, which was initiated by the aqueous component separating from the bottom part of the sample. The resultant phase separation was the most distinct among the test samples. To investigate the phase separation quantitatively and objectively, we conducted a histogram analysis on the acquired T 2 maps. The water-in-oil type creams were found to be much more stable after mixing with ointment base than those of oil-in-water type creams. This finding strongly supported the validity of the mixing operation traditionally conducted in pharmacies.
ERIC Educational Resources Information Center
Tagay, Özlem
2015-01-01
Problem Statement: A literature analysis revealed that contact disturbances, self-esteem and life satisfaction have been examined in different studies separately. In particular, the researchers observed that the studies conducted on Gestalt contact disturbances are limited in number. In this study, the variables of contact disturbances,…
NASA Astrophysics Data System (ADS)
Lü, Ting; Zhang, Shuang; Qi, Dongming; Zhang, Dong; Vance, George F.; Zhao, Hongting
2017-02-01
Emulsified oil wastewaters, arisen from oil industry and oil spill accidents, cause severe environmental and ecological problems. In this study, a series of pH-sensitive magnetic nanomaterials (MNPs) were synthesized and characterized for their evaluation in separation of emulsified oil from aqueous environments. A coprecipitation method was used to produce Fe3O4 magnetic nanoparticles that were coated in a 2-step process with first silica to form a surface for anchoring an (3-aminopropyl)triethoxysilane (APTES) molecular layer. Detailed studies were conducted on effects of MNPs dosage, APTES anchoring density (DA) and pH on oil-water separation performance of the synthetic MNPs. Results showed that, under both acidic and neutral conditions, MNPs with high DA exhibited enhanced oil-water separation performance, while under alkaline condition, the oil-water separation process was minimal. Alkaline conditions allowed the MNPs to be recycled up to 9 cycles without showing any significant decrease in oil-water separation efficiency. An examination of the oil-water separation mechanism found that electrostatic interaction and interfacial activity both played important roles in oil-water separation. In conclusion, pH-sensitive MNPs can be easily synthesized and recycled, providing a promising, cost-effective and environmentally-friendly process for the efficient treatment of emulsified oil wastewater.
Waller, Rebecca; Hyde, Luke W; Grabell, Adam S; Alves, Martha L; Olson, Sheryl L
2015-06-01
Early-starting child conduct problems (CP) are linked to the development of persistent antisocial behavior. Researchers have theorized multiple pathways to CP and that CP comprise separable domains, marked by callous-unemotional (CU) behavior, oppositional behavior, or ADHD symptoms. However, a lack of empirical evidence exists from studies that have examined whether there are unique correlates of these domains. We examined differential correlates of CU, oppositional, and ADHD behaviors during the preschool years to test their potentially distinct nomological networks. Multimethod data, including parent and teacher reports and observations of child behavior, were drawn from a prospective, longitudinal study of children assessed at age 3 and age 6 (N = 240; 48% female). Dimensions of CU, oppositional, and ADHD behaviors were separable within Confirmatory Factor Analyses across mother and father reports. There were differential associations between CU, oppositional, and ADHD behaviors and socioemotional, cognitive, and behavioral outcomes: CU behavior was uniquely related to lower moral regulation, guilt, and empathy. ADHD was uniquely related to lower attentional focusing and observed effortful control. Finally, CU behavior uniquely predicted increases in teacher-reported externalizing from ages 3-6 over and above covariates, and ADHD and oppositional behavior. Consistent with theory, dimensions of CU, ADHD, and oppositional behavior demonstrated separable nomological networks representing separable facets within early-starting CP. © 2014 Association for Child and Adolescent Mental Health.
Alternative Chemical Cleaning Methods for High Level Waste Tanks: Simulant Studies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rudisill, T.; King, W.; Hay, M.
Solubility testing with simulated High Level Waste tank heel solids has been conducted in order to evaluate two alternative chemical cleaning technologies for the dissolution of sludge residuals remaining in the tanks after the exhaustion of mechanical cleaning and sludge washing efforts. Tests were conducted with non-radioactive pure phase metal reagents, binary mixtures of reagents, and a Savannah River Site PUREX heel simulant to determine the effectiveness of an optimized, dilute oxalic/nitric acid cleaning reagent and pure, dilute nitric acid toward dissolving the bulk non-radioactive waste components. A focus of this testing was on minimization of oxalic acid additions duringmore » tank cleaning. For comparison purposes, separate samples were also contacted with pure, concentrated oxalic acid which is the current baseline chemical cleaning reagent. In a separate study, solubility tests were conducted with radioactive tank heel simulants using acidic and caustic permanganate-based methods focused on the “targeted” dissolution of actinide species known to be drivers for Savannah River Site tank closure Performance Assessments. Permanganate-based cleaning methods were evaluated prior to and after oxalic acid contact.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lawrence, W.E.; Kurath, D.E.
1994-04-01
The US Department of Energy has established the Tank Waste Remediation System (TWRS) to manage and dispose of radioactive wastes stored at the Hanford Site. Within this program are evaluations of pretreatment system alternatives through literature reviews. The information in this report was collected as part of this project at Pacific Northwest Laboratory. A preliminary survey of literature on separations recently entered into the Hanford electronic databases (1992--1993) that have the potential for pretreatment of Hanford tank waste was conducted. Separation processes that can assist in the removal of actinides (uranium, plutonium, americium), lanthanides, barium, {sup 137}Cs, {sup 90}Sr,{sup 129more » }I, {sup 63}Ni, and {sup 99}Tc were evaluated. Separation processes of interest were identified through literature searches, journal reviews, and participation in separation technology conferences. This report contains brief descriptions of the potential separation processes, the extent and/or selectivity of the separation, the experimental conditions, and observations. Information was collected on both national and international separation studies to provide a global perspective on recent research efforts.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jubin, R.T.
This report summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division at Oak Ridge National Laboratory (ORNL) during the period July--September 1997. The section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within nine major areas of research: Hot Cell Operations, Process Chemistry and Thermodynamics, Molten Salt Reactor Experiment (MSRE) Remediation Studies, Chemistry Research, Biotechnology, Separations and Materials Synthesis, Fluid Structure and Properties, Biotechnologymore » Research, and Molecular Studies. The name of a technical contact is included with each task described, and readers are encouraged to contact these individuals if they need additional information.« less
Teaching from a Distance: "Hello, Is Anyone Out There?"
ERIC Educational Resources Information Center
Mottet, Timothy P.
This small, qualitative study examined how interactive television educators go about teaching in electronically-mediated environments where students remain separated from them. Three interactive television instructors were interviewed, and 15 hours of field observation was conducted. Although the study's original goal was to yield prescriptions…
Electrospun Nanofiber-Coated Membrane Separators for Lithium-Ion Batteries
NASA Astrophysics Data System (ADS)
Lee, Hun
Lithium-ion batteries are widely used as a power source for portable electronic devices and hybrid electric vehicles due to their excellent energy and power densities, long cycle life, and enhanced safety. A separator is considered to be the critical component in lithium-ion rechargeable batteries. The separator is placed between the positive and negative electrodes in order to prevent the physical contact of electrodes while allowing the transportation of ions. In most commercial lithium-ion batteries, polyolefin microporous membranes are commonly used as the separator due to their good chemical stability and high mechanical strength. However, some of their intrinsic natures, such as low electrolyte uptake, poor adhesion property to the electrodes, and low ionic conductivity, can still be improved to achieve higher performance of lithium-ion batteries. In order to improve these intrinsic properties, polyolefin microporous membranes can be coated with nanofibers by using electrospinning technique. Electrospinning is a simple and efficient method to prepare nanofibers which can absorb a significant amount of liquid electrolyte to achieve low internal resistance and battery performance. This research presents the preparation and investigation of composite membrane separators prepared by coating nanofibers onto polyolefin microporous membranes via electrospinning technique. Polyvinylidene fluoride polymers and copolymers were used for the preparation of electrospun nanofiber coatings because they have excellent electrochemical stability, good adhesion property, and high temperature resistance. The nanofiber coatings prepared by electrospinning form an interconnected and randomly orientated structure on the surface of the polyolefin microporous membranes. The size of the nanofibers is on a scale that does not interfere with the micropores in the membrane substrates. The resultant nanofiber-coated membranes have the potential to combine advantages of both the polyolefin separator membranes and the nanoscale fibrous polymer coatings. The polyolefin microporous membranes serve as the supporting substrate which provides the required mechanical strength for the assembling process of lithium-ion batteries. The electrospun nanofiber coatings improve the wettability of the composite membrane separators to the liquid electrolyte, which is desirable for the lithium-ion batteries with high kinetics and good cycling performance. The results show that the nanofiber-coated membranes have enhanced adhesion properties to the battery electrode which can help prevent the formation of undesirable gaps between the separators and electrodes during prolonged charge-discharge cycles, especially in large-format batteries. The improvement on adhesive properties of nanofiber-coated membranes was evaluated by peel test. Nanofiber coatings applied to polyolefin membrane substrates improve the adhesion of separator membranes to battery electrodes. Electrolyte uptakes, ionic conductivities and interfacial resistances of the nanofiber-coated membrane separators were studied by soaking the membrane separators with a liquid electrolyte solution of 1 M lithium hexafluorophosphate dissolved in ethylene carbonate/dimethylcarbonate/ethylmethyl carbonate (1:1:1 vol). The nanofiber coatings on the surface of the membrane substrates increase the electrolyte uptake capacity due to the high surface area and capillary effect of nanofibers. The nanofiber-coated membranes soaked in the liquid electrolyte solution exhibit high ionic conductivities and low interfacial resistances to the lithium electrode. The cells containing LiFePO 4 cathode and the nanofiber-coated membranes as the separator show high discharge specific capacities and good cycling stability at room temperature. The nanofiber coatings on the membrane substrates contribute to high ionic conductivity and good electrochemical performance in lithium-ion batteries. Therefore, these nanofiber-coated composite membranes can be directly used as novel battery separators for high performance of lithium-ion batteries. Coating polyolefin microporous membranes with electrospun nanofibers is a promising approach to obtain highperformance separators for advanced lithium-ion batteries.
Giant oscillating magnetoresistance in silicene-based structures
NASA Astrophysics Data System (ADS)
Oubram, O.; Navarro, O.; Rodríguez-Vargas, I.; Guzman, E. J.; Cisneros-Villalobos, L.; Velásquez-Aguilar, J. G.
2018-02-01
Ballistic electron transport in a silicene structure, composed of a pair of magnetic gates, in the ferromagnetic and an-tiferromagnetic configuration is studied. This theoretical study has been done using the matrix transfer method to calculate the transmission, the conductance for parallel and antiparallel magnetic alignment and the magnetoresistance. Results show that conductance and magnetoresistance oscillate as a function of the length between the two magnetic domains. The forbidden transmission region also increases as a function of the barrier separation distance.
1992-10-01
DBMBF2 ) undergoes photoreaction with olefins through a partial electron transfer that leads to cycloaddition or sensitized Diels - Alder reactions. We...8217 Fluorescence. 10:00 J.M. WARMAN: Photon-induced Intramolecular Charge Sepaiation Studied byTime-Resolved Microwave Conductivity. 10:30 Coffee 11:)) W...26 Photon-Induced Intramolecular Charge Separation Studied by Time-Resolved Microwave Conductivity John M. Warman IRI, Delft University of Technology
Novel Polyimide Battery Separator Imbibed with Room-Temperature Ionic Liquids
NASA Technical Reports Server (NTRS)
Viggiano, Rocco; Nguyen, Baochau; Wu, James; Dai, Liming; Meador, Mary Ann
2017-01-01
The journey to Mars will require advancements in many existing technologies, including space power and energy storage systems. According to the 2015 NASA Technology Roadmaps, energy storage is a critical technology area to develop for both terrestrial as well as future long-term space missions. Currently, batteries represent one of the major areas in need of advancement, both in terms of energy density as well as safety. Recently, concerns regarding the fire safety of commercial lithium-ion batteries have prompted efforts to produce nonflammable battery components, namely the electrolyte and separator. Commercial lithium-ion batteries utilize polyolefin separators imbibed with a lithium salt dissolved in cyclic carbonates. This separator/electrolyte combination imparts good ionic conductivities in the range of 10(exp -2) to 10(exp -3) S/cm. However, the cyclic carbonates and polyolefin separator are inherently flammable. Room-temperature ionic liquids (RTILs) appear to be a safer alternative to cyclic carbonates. They offer good ionic conductivities, similar to those observed in cyclic carbonates, but are inherently nonvolatile and nonflammable giving them a safety advantage. Many promising RTILs for battery electrolytes are not compatible with commercial polyolefin separator materials. Polyimide aerogels possess an open-porous, fibrillar network architecture which offers a high degree of porosity (typically greater than 85 porous), required for lithium ion conduction, as well as good mechanical properties. Furthermore, these materials are compatible with all tested RTILs. By creating a polyimide gel and imbibing the gel with a RTIL containing a lithium salt instead of super critically drying them to form aerogels, a nonflammable separator/electrolyte system with conductivities in the range of 1x10(exp -3) S/cm has been demonstrated.
Progress in Ion Transport Membranes for Gas Separation Applications
NASA Astrophysics Data System (ADS)
Bose, Arun C.; Stiegel, Gary J.; Armstrong, Phillip A.; Halper, Barry J.; (Ted) Foster, E. P.
This chapter describes the evolution and advances of ion transport membranes for gas separation applications, especially separation of oxygen from air. In partnership with the US Department of Energy (DOE), Air Products and Chemicals, Inc. (Air Products) successfully developed a novel class of mixed ion-electron conducting materials and membrane architecture. These novel materials are referred to as ion transport membranes (ITM). Generically, ITMs consist of modified perovskite and brownmillerite oxide solid electrolytes and provide high oxygen anion and electron conduction typically at high temperatures driven by an oxygen potential gradient without the need for external power. The partial pressure ratio across the ITM layer creates the driving force for oxygen separation.
Method for forming a cell separator for use in bipolar-stack energy storage devices
Mayer, Steven T.; Feikert, John H.; Kaschmitter, James L.; Pekala, Richard W.
1994-01-01
An improved multi-cell electrochemical energy storage device, such as a battery, fuel cell, or double layer capacitor using a cell separator which allows cells to be stacked and interconnected with low electrical resistance and high reliability while maximizing packaging efficiency. By adding repeating cells, higher voltages can be obtained. The cell separator is formed by applying an organic adhesive on opposing surfaces of adjacent carbon electrodes or surfaces of aerogel electrodes of a pair of adjacent cells prior to or after pyrolysis thereof to form carbon aerogel electrodes. The cell separator is electronically conductive, but ionically isolating, preventing an electrolytic conduction path between adjacent cells in the stack.
Cell separator for use in bipolar-stack energy storage devices
Mayer, S.T.; Feikert, J.H.; Kachmitter, J.L.; Pekala, R.W.
1995-02-28
An improved multi-cell electrochemical energy storage device is described, such as a battery, fuel cell, or double layer capacitor using a cell separator which allows cells to be stacked and interconnected with low electrical resistance and high reliability while maximizing packaging efficiency. By adding repeating cells, higher voltages can be obtained. The cell separator is formed by applying an organic adhesive on opposing surfaces of adjacent carbon electrodes or surfaces of aerogel electrodes of a pair of adjacent cells prior to or after pyrolysis thereof to form carbon aerogel electrodes. The cell separator is electronically conductive, but ionically isolating, preventing an electrolytic conduction path between adjacent cells in the stack. 2 figs.
Method for forming a cell separator for use in bipolar-stack energy storage devices
Mayer, S.T.; Feikert, J.H.; Kaschmitter, J.L.; Pekala, R.W.
1994-08-09
An improved multi-cell electrochemical energy storage device, such as a battery, fuel cell, or double layer capacitor using a cell separator which allows cells to be stacked and interconnected with low electrical resistance and high reliability while maximizing packaging efficiency. By adding repeating cells, higher voltages can be obtained. The cell separator is formed by applying an organic adhesive on opposing surfaces of adjacent carbon electrodes or surfaces of aerogel electrodes of a pair of adjacent cells prior to or after pyrolysis thereof to form carbon aerogel electrodes. The cell separator is electronically conductive, but ionically isolating, preventing an electrolytic conduction path between adjacent cells in the stack. 2 figs.
Code of Federal Regulations, 2010 CFR
2010-10-01
... relocation agreement. Sprint Nextel and relocating incumbents may agree to conduct face-to-face negotiations...-55. Sprint Nextel and relocating incumbents may agree to conduct face-to-face negotiations or either... in order to separate cellular systems from non-cellular systems. 90.677 Section 90.677...
Derived Basic Ability Factors: A Factor Analysis Replication Study.
ERIC Educational Resources Information Center
Lee, Mickey, M.; Lee, Lynda Newby
The purpose of this study was to replicate the study conducted by Potter, Sagraves, and McDonald to determine whether their recommended analysis could separate criterion variables into similar factors that were stable from year to year and from school to school. The replication samples consisted of all students attending Louisiana State University…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-27
... conduct survey and instrument design and administration, focus groups, cognitive interviews, and health..., recruitment, consent and questionnaire design, and retention activities. Under separate notice, the NCS also... study of this size and complexity, the NCS was designed to include a preliminary pilot study known as...
A Mental Health Training Format for Adult Education Teachers
ERIC Educational Resources Information Center
Meek, Fiona; Specht, Jacqueline; Rodger, Susan
2017-01-01
The present study investigated the needs of adult education staff pertaining to adult students' mental health issues within a local school board. The study utilized mixed-methods design and was divided into progression of three separate studies. An initial focus group was conducted to identify the 12 participants' concerns and provide a direction…
The Effect of Constructivism on Attitudes towards Lessons: A Meta-Analysis Study
ERIC Educational Resources Information Center
Toraman, Cetin; Demir, Engin
2016-01-01
Problem Statement: A number of recent studies on constructivism that have been conducted separately (independently) have arrived at very different results. Throughout the ten-year period in which the constructivist approach has been applied, there have been studies that have researched the effect of the newly-introduced approach on student…
Vortex Formation During Unsteady Boundary-Layer Separation
NASA Astrophysics Data System (ADS)
Das, Debopam; Arakeri, Jaywant H.
1998-11-01
Unsteady laminar boundary-layer separation is invariably accompanied by the formation of vortices. The aim of the present work is to study the vortex formation mechanism(s). An adverse pressure gradient causing a separation can be decomposed into a spatial component ( spatial variation of the velocity external to the boundary layer ) and a temporal component ( temporal variation of the external velocity ). Experiments were conducted in a piston driven 2-D water channel, where the spatial component could be be contolled by geometry and the temporal component by the piston motion. We present results for three divergent channel geometries. The piston motion consists of three phases: constant acceleration from start, contant velocity, and constant deceleration to stop. Depending on the geometry and piston motion we observe different types of unsteady separation and vortex formation.
Pini, Stefano; Abelli, Marianna; Troisi, Alfonso; Siracusano, Alberto; Cassano, Giovanni B; Shear, Katherine M; Baldwin, David
2014-12-01
Epidemiological studies indicate that separation anxiety disorder occurs more frequently in adults than children. It is unclear whether the presence of adult separation anxiety disorder (ASAD) is a manifestation of anxious attachment, or a form of agoraphobia, or a specific condition with clinically significant consequences. We conducted a study to examine these questions. A sample of 141 adult outpatients with panic disorder participated in the study. Participants completed standardized measures of separation anxiety, attachment style, agoraphobia, panic disorder severity and quality of life. Patients with ASAD (49.5% of our sample) had greater panic symptom severity and more impairment in quality of life than those without separation anxiety. We found a greater rate of symptoms suggestive of anxious attachment among panic patients with ASAD compared to those without ASAD. However, the relationship between ASAD and attachment style is not strong, and adult ASAD occurs in some patients who report secure attachment style. Similarly, there is little evidence for the idea that separation anxiety disorder is a form of agoraphobia. Factor analysis shows clear differentiation of agoraphobic and separation anxiety symptoms. Our data corroborate the notion that ASAD is a distinct condition associated with impairment in quality of life and needs to be better recognized and treated in patients with panic disorder. Copyright © 2014. Published by Elsevier Ltd.
Rate- and Temperature-Dependent Material Behavior of a Multilayer Polymer Battery Separator
NASA Astrophysics Data System (ADS)
Avdeev, Ilya; Martinsen, Michael; Francis, Alex
2014-01-01
Designing battery packs for safety in automotive applications requires multiscale modeling, as macroscopic deformations due to impact cause the mechanical failure of individual cells on a sub-millimeter level. The separator material plays a critical role in this process, as the thinning or perforating of the separator can lead to thermal runaway and catastrophic failure of an entire battery pack. The electrochemical properties of various polymer separators have been extensively investigated; however, the dependency of mechanical properties of these thin films on various factors, such as high temperature and strain rate, has not been sufficiently characterized. In this study, the macroscopic mechanical properties of a multilayer polymer thin film used as a battery separator are studied experimentally at various temperatures, strain rates, and solvent saturations. Due to the anisotropy of the material, material testing was conducted in two perpendicular directions (machine and transverse directions). Material samples were tested in both dry and saturated conditions at several temperatures, and it was found that temperature and strain rate have a nearly linear effect on the stress experienced by the material. Additionally, saturating the separator material in a common lithium-ion solvent had softened it and had a positive effect on its toughness. The experimental results obtained in this study can be used to develop mathematical constitutive models of the multilayer separator material for subsequent numerical simulations and design.
Fehr, M
2014-09-01
Business opportunities in the household waste sector in emerging economies still evolve around the activities of bulk collection and tipping with an open material balance. This research, conducted in Brazil, pursued the objective of shifting opportunities from tipping to reverse logistics in order to close the balance. To do this, it illustrated how specific knowledge of sorted waste composition and reverse logistics operations can be used to determine realistic temporal and quantitative landfill diversion targets in an emerging economy context. Experimentation constructed and confirmed the recycling trilogy that consists of source separation, collection infrastructure and reverse logistics. The study on source separation demonstrated the vital difference between raw and sorted waste compositions. Raw waste contained 70% biodegradable and 30% inert matter. Source separation produced 47% biodegradable, 20% inert and 33% mixed material. The study on collection infrastructure developed the necessary receiving facilities. The study on reverse logistics identified private operators capable of collecting and processing all separated inert items. Recycling activities for biodegradable material were scarce and erratic. Only farmers would take the material as animal feed. No composting initiatives existed. The management challenge was identified as stimulating these activities in order to complete the trilogy and divert the 47% source-separated biodegradable discards from the landfills. © The Author(s) 2014.
Playing with Nature: Supporting Preschoolers' Creativity in Natural Outdoor Classrooms
ERIC Educational Resources Information Center
Kiewra, Christine; Veselack, Ellen
2016-01-01
Conducted at two separate natural outdoor classrooms with preschool-aged children from three to five years old, this qualitative research study investigated how outdoor environments supported children's creativity and imagination. Although many studies have explored the development of creative arts in the young children, few have focused on…
Experimental Study of Unsteady Separation in a Laminar Boundary Layer
NASA Astrophysics Data System (ADS)
Bonacci, Andrew; Lang, Amy; Wahidi, Redha; Santos, Leo
2016-11-01
Separation, caused by an adverse pressure gradient, can be a major problem to aircraft. Reversing flow occurs in separated regions and an investigation of how this backflow forms is of interest due to the fact that this could be used as a means of initiating flow control. Specifically, backflow can bristle shark scales which may be linked to a passive, flow actuated separation control mechanism. An experiment was conducted in a water tunnel to replicate separation, with a focus on the reversing flow development near the wall within a laminar boundary layer. Using a rotating cylinder, an adverse pressure gradient was induced creating a separated region over a flat plate. In this experiment the boundary layer grows to sizes great enough that the scale of the flow is increased, making it more measurable to DPIV. In the future, this research can be utilized to better understand flow control mechanisms such as those enabled by shark skin. Funding from Army Research Office and NSF REU site Grant EEC 1358991 is greatly appreciated.
ERIC Educational Resources Information Center
Ay, Ismail; Secer, Ismail; Simsek, Mustafa Kerim
2017-01-01
Purpose of this study is to adapt anxiety and depression questionnaire for children into Turkish culture and to analyze the psychometric characteristics of it on clinical and nonclinical samples separately. The study is a descriptive survey research. The study was conducted on two different sample groups, clinical and nonclinical. The clinical…
Electric microwave absorption for the study of GaAs/AlGaAs heterostructure systems
NASA Astrophysics Data System (ADS)
Zappe, Hans P.; Jantz, Wolfgang
1990-12-01
The use of magnetic-field-dependent microwave absorption as a nondestructive and contact-free means to study transport behavior in GaAs/AlGaAs devices is explored. This technique allows quick measurement of resistance, mobility, and carrier concentration in bulk substrates as well as in the two-dimensional electron gas of heterostructure quantum wells. The two- and three-dimensional conductivities may be separably evaluated, allowing detailed study of conduction in the active layer of high-electron-mobility devices. A brief theoretical foundation is provided, followed by application of the approach to examination of device structural dependencies, carrier-density conduction behavior, and the effects of etch processing on quantum-well integrity.
Conducting polymer networks synthesized by photopolymerization-induced phase separation
NASA Astrophysics Data System (ADS)
Yamashita, Yuki; Komori, Kana; Murata, Tasuku; Nakanishi, Hideyuki; Norisuye, Tomohisa; Yamao, Takeshi; Tran-Cong-Miyata, Qui
2018-03-01
Polymer mixtures composed of double networks of a polystyrene derivative (PSAF) and poly(methyl methacrylate) (PMMA) were alternatively synthesized by using ultraviolet (UV) and visible (Vis) light. The PSAF networks were generated by UV irradiation to photodimerize the anthracene (A) moieties labeled on the PSAF chains, whereas PMMA networks were produced by photopolymerization of methyl methacrylate (MMA) monomer and the cross-link reaction using ethylene glycol dimethacrylate (EGDMA) under Vis light irradiation. It was found that phase separation process of these networks can be independently induced and promptly controlled by using UV and Vis light. The characteristic length scale distribution of the resulting co-continuous morphology can be well regulated by the UV and Vis light intensity. In order to confirm and utilize the connectivity of the bicontinuous morphology observed by confocal microscopy, a very small amount, 0.1 wt%, of multi-walled carbon nanotubes (MWCNTs) was introduced into the mixture and the current-voltage (I-V) relationship was subsequently examined. Preliminary data show that MWCNTs are preferentially dispersed in the PSAF-rich continuous domains and the whole mixture became electrically conducting, confirming the connectivity of the observed bi-continuous morphology. The experimental data obtained in this study reveal a promising method to design various scaffolds for conducting soft matter taking advantages of photopolymerization-induced phase separation.
NASA Astrophysics Data System (ADS)
Nykaza, Jacob Richard
In this study, polymerized ionic liquid (PIL) diblock copolymers were explored as solid-state polymer separators as an anion exchange membrane (AEM) for alkaline fuel cells AFCs and as a solid polymer electrolyte (SPE) for lithium-ion batteries. Polymerized ionic liquid (PIL) block copolymers are a distinct set of block copolymers that combine the properties of both ionic liquids (e.g., high conductivity, high electrochemical stability) and block copolymers (e.g., self-assembly into various nanostructures), which provides the opportunity to design highly conductive robust solid-state electrolytes that can be tuned for various applications including AFCs and lithium-ion batteries via simple anion exchange. A series of bromide conducting PIL diblock copolymers with an undecyl alkyl side chain between the polymer backbone and the imidazolium moiety were first synthesized at various compositions comprising of a PIL component and a non-ionic component. Synthesis was achieved by post-functionalization from its non-ionic precursor PIL diblock copolymer, which was synthesized via the reverse addition fragmentation chain transfer (RAFT) technique. This PIL diblock copolymer with long alkyl side chains resulted in flexible, transparent films with high mechanical strength and high bromide ion conductivity. The conductivity of the PIL diblock copolymer was three times higher than its analogous PIL homopolymer and an order of magnitude higher than a similar PIL diblock copolymer with shorter alkyl side chain length, which was due to the microphase separated morphology, more specifically, water/ion clusters within the PIL microdomains in the hydrated state. Due to the high conductivity and mechanical robustness of this novel PIL block copolymer, its application as both the ionomer and AEM in an AFC was investigated via anion exchange to hydroxide (OH-), where a maximum power density of 29.3 mW cm-1 (60 °C with H2/O2 at 25 psig (172 kPa) backpressure) was achieved. Rotating disk electrode (RDE) experiments determined the interfacial resistance imposed during cell assembly between the AEM, catalyst, and ionomer was a factor in fuel cell performance. Further RDE studies investigated the electrochemical stability of the PIL block copolymer ionomer under applied potentials, where it was determined that potential cycling increased the degradation compared to constant voltage or open circuit voltage studies. The PIL diblock copolymer was then anion exchanged to the bis(trifluoromethane)sulfonamide (TFSI-) anion form and imbibed with a lithium salt and ionic liquid solution for use as a SPE in lithium-ion batteries resulting in a maximum discharge capacity of 112 mAh g-1 at 0.1 C with a Coulombic efficiency greater than 94% over 100 cycles. PIL block copolymers have promising mechanical properties and transport properties (i.e., ion conductivity) in both the hydrated (hydrophilic anions; Br-, OH-) and dry (hydrophobic anions; TFSI-) states resulting in highly conductive, chemically/thermally stable, and mechanically robust solid-state polymer separators for use as AEMs in AFCs and as SPEs in lithium-ion batteries.
Parental separation in childhood and self-reported psychological health: A population-based study.
Lindström, Martin; Rosvall, Maria
2016-12-30
The aim of the present study is to investigate associations between parental separation/divorce during childhood, and self-reported psychological health, adjusting for social capital, social support, civil status and economic stress in childhood. A cross-sectional public health survey was conducted in the autumn of 2012 in Scania, southern Sweden, with a postal questionnaire with 28,029 participants aged 18-80. Associations between parental separation/divorce during childhood and self-reported psychological health (GHQ12) were investigated using logistic regressions. A 16.1% proportion of all men 22.4% of all women reported poor psychological health. Among men, 20.4% had experienced parental separation during childhood until age 18 years, the corresponding prevalence among women was 22.3%. Parental separation/divorce in childhood was significantly associated with poor self-rated psychological health among men who had experienced parental separation/divorce at ages 0-4, and among women with this experience at ages 0-4, 10-14 and 15-18. These significant associations remained throughout the multiple analyses. The results support the notion that the experience of parental separation/divorce in childhood may influence psychological health in adulthood, particularly if it is experienced in the age interval 0-4 years. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Micromachined peristaltic pump
NASA Technical Reports Server (NTRS)
Hartley, Frank T. (Inventor)
1998-01-01
A micromachined pump including a channel formed in a semiconductor substrate by conventional processes such as chemical etching. A number of insulating barriers are established in the substrate parallel to one another and transverse to the channel. The barriers separate a series of electrically conductive strips. An overlying flexible conductive membrane is applied over the channel and conductive strips with an insulating layer separating the conductive strips from the conductive membrane. Application of a sequential voltage to the series of strips pulls the membrane into the channel portion of each successive strip to achieve a pumping action. A particularly desirable arrangement employs a micromachined push-pull dual channel cavity employing two substrates with a single membrane sandwiched between them.
Multi-layer coatings for bipolar rechargeable batteries with enhanced terminal voltage
Farmer, Joseph C.; Kaschmitter, James; Pierce, Steve
2017-06-06
A method for producing a multi-layer bipolar coated cell according to one embodiment includes applying a first active cathode material above a substrate to form a first cathode; applying a first solid-phase ionically-conductive electrolyte material above the first cathode to form a first electrode separation layer; applying a first active anode material above the first electrode separation layer to form a first anode; applying an electrically conductive barrier layer above the first anode; applying a second active cathode material above the anode material to form a second cathode; applying a second solid-phase ionically-conductive electrolyte material above the second cathode to form a second electrode separation layer; applying a second active anode material above the second electrode separation layer to form a second anode; and applying a metal material above the second anode to form a metal coating section. In another embodiment, the anode is formed prior to the cathode. Cells are also disclosed.
Lee, Chia-Yen; Chen, C M; Chang, Guan-Liang; Lin, Che-Hsin; Fu, Lung-Ming
2006-12-01
This study uses simple and reliable microfabrication techniques to fabricate CE biochips, integrating a novel contactless conductivity detector in a miniaturized detection system in a microfluidic biochip. The off-channel electrodes are deposited around side channels by Au sputtering and patterned using a standard "lift-off" process. A vacuum fusion bonding process is employed to seal the lower substrate containing the microchannels and the electrodes to an upper glass cover plate. The variations in the capacitance between the semicircular detection electrodes in the side channels are measured as different samples and ions pass through the detection region of the CE separation channel. Samples of Rhodamine B, commercial sports drinks, mineral waters, and a red wine, respectively, are mixed in different buffer solutions, separated, and successfully detected using the developed device. The semicircular detection electrodes for the contactless conductivity detector have microscale dimensions and provide a valuable contribution to the realization of the lab-on-a-chip concept.
HOV Project Case Studies, History and Institutional Arrangements
DOT National Transportation Integrated Search
1990-12-01
The Texas Transportation Institute (TTI), a part of The Texas A&M University : System, is conducting an assessment of high-occupancy vehicle (HOV) projects : located either on freeways or in separate rights-of-way in North America. The : three-year r...
NASA Astrophysics Data System (ADS)
Saeed, O.; Duru, L.; Yulin, D.
2018-05-01
A proposed microfluidic design has been fabricated and simulated using COMSOL Multiphysics software, based on two physical models included in this design. The device’s ability to create a narrow stream of the core sample by controlling the sheath flow rates Qs1 and Qs2 in both peripheral channels was investigated. The main target of this paper is to study the possibility of combing the hydrodynamic and magnetic techniques, in order to achieve a high rate of cancer cells separation from a cell mixture and/or buffer sample. The study has been conducted in two stages, firstly, the effects of the sheath flow rates (Qs1 and Qs2) on the sample stream focusing were studied, to find the proposed device effectiveness optimal conditions and its capability in cell focusing, and then the magnetic mechanism has been utilized to finalize the pre-labelled cells separation process.
Aquagel electrode separator for use in batteries and supercapacitors
Mayer, Steven T.; Kaschmitter, James L.; Pekala, Richard W.
1995-01-01
An electrode separator for electrochemical energy storage devices, such as a high energy density capacitor incorporating a variety of carbon foam electrodes. The separator is derived from an aquagel of resorcinol-formaldehyde and related polymers and containing ionically conducting electrolyte in the pores thereof.
Recalled Separation Anxiety in Childhood in Istmo Zapotec Men, Women, and Muxes.
Gómez, Francisco R; Semenyna, Scott W; Court, Lucas; Vasey, Paul L
2017-01-01
The Istmo Zapotec are a pre-Columbian cultural group indigenous to the Istmo region of Oaxaca, Mexico. Istmo Zapotec recognize three genders: men, women, and muxes. Like Istmo Zapotec men, muxes are biological males. However, unlike Istmo Zapotec men, most muxes are exclusively androphilic (i.e., sexually attracted to adult males), relatively feminine, and routinely adopt the receptive role during anal intercourse. Furthermore, the Istmo Zapotec recognize two types of muxes: muxe gunaa, who resemble the transgender androphilic males that are common in many non-Western cultures, and muxe nguiiu, who resemble the cisgender androphilic males ("gay" men) common in Western cultures. Retrospective research conducted in Canada and Samoa demonstrates that cisgender and transgender androphilic males recall elevated indicators of childhood separation anxiety (i.e., feelings of distress related to separation from major attachment figures) when compared to males who are gynephilic (i.e., sexually attracted to adult females). The present study compared recalled indicators of childhood separation anxiety among Istmo Zapotec men, women, muxe gunaa, and muxe nguiiu (N = 454). Men recalled significantly lower levels of childhood separation anxiety compared to all other groups (all p < .042). No additional group differences were found. Our results are consistent with previous research conducted in Canada and Samoa, suggesting that elevated childhood separation anxiety is a developmental correlate of male androphilia that is cross-culturally universal. This research is also consistent with the conclusion that cisgender and transgender male androphiles share a common biological and developmental foundation despite being different in appearance.
Hyper-X Stage Separation: Background and Status
NASA Technical Reports Server (NTRS)
Reubush, David E.
1999-01-01
This paper provides an overview of stage separation activities for NASA's Hyper-X program; a focused hypersonic technology effort designed to move hypersonic, airbreathing vehicle technology from the laboratory environment to the flight environment. This paper presents an account of the development of the current stage separation concept, highlights of wind tunnel experiments and computational fluid dynamics investigations being conducted to define the separation event, results from ground tests of separation hardware, schedule and status. Substantial work has been completed toward reducing the risk associated with stage separation.
Passive safety device and internal short tested method for energy storage cells and systems
Keyser, Matthew; Darcy, Eric; Long, Dirk; Pesaran, Ahmad
2015-09-22
A passive safety device for an energy storage cell for positioning between two electrically conductive layers of the energy storage cell. The safety device also comprising a separator and a non-conductive layer. A first electrically conductive material is provided on the non-conductive layer. A first opening is formed through the separator between the first electrically conductive material and one of the electrically conductive layers of the energy storage device. A second electrically conductive material is provided adjacent the first electrically conductive material on the non-conductive layer, wherein a space is formed on the non-conductive layer between the first and second electrically conductive materials. A second opening is formed through the non-conductive layer between the second electrically conductive material and another of the electrically conductive layers of the energy storage device. The first and second electrically conductive materials combine and exit at least partially through the first and second openings to connect the two electrically conductive layers of the energy storage device at a predetermined temperature.
Utterance Complexity and Stuttering on Function Words in Preschool-Age Children Who Stutter
ERIC Educational Resources Information Center
Richels, Corrin; Buhr, Anthony; Conture, Edward; Ntourou, Katerina
2010-01-01
The purpose of the present investigation was to examine the relation between utterance complexity and utterance position and the tendency to stutter on function words in preschool-age children who stutter (CWS). Two separate studies involving two different groups of participants (Study 1, n = 30; Study 2, n = 30) were conducted. Participants were…
Development and Validation of Supervisory Behaviour Description Scale
ERIC Educational Resources Information Center
Unal, Ali
2013-01-01
The aim of this study is to develop a scale which will describe how education supervisors' behaviours are perceived. Four separate studies have been conducted in order to develop the scale. In the first study the scale that was developed is applied to a working group consisting of 704 teachers. The factor structure of the scale is examined by…
Embedded Heaters for Joining or Separating Plastic Parts
NASA Technical Reports Server (NTRS)
Bryant, Melvin A., III
2004-01-01
A proposed thermal-bonding technique would make it possible to join or separate thermoplastic parts quickly and efficiently. The technique would eliminate the need for conventional welding or for such conventional fastening components as bolted flanges or interlocking hooks. The technique could be particularly useful in the sign industry (in which large quantities of thermoplastics are used) or could be used to join plastic pipes. A thin sheet of a suitable electrically conductive material would be formed to fit between two thermoplastic parts to be joined (see figure). The electrically conductive sheet and the two parts would be put together tightly, then an electrical current would be sent through the conductor to heat the thermoplastic locally. The magnitude of the current and the heating time would be chosen to generate just enough heat to cause the thermoplastic to adhere to both sides of the electrically conductive sheet. Optionally, the electrically conductive sheet could contain many small holes to provide purchase or to increase electrical resistance to facilitate the generation of heat. After thermal bonding, the electrically conductive sheet remains as an integral part of the structure. If necessary, the electrically conductive sheet can be reheated later to separate the joined thermoplastic parts.
Facile and Nonradiation Pretreated Membrane as a High Conductive Separator for Li-Ion Batteries.
Li, Bao; Li, Yongjun; Dai, Dongmei; Chang, Kun; Tang, Hongwei; Chang, Zhaorong; Wang, Chunru; Yuan, Xiao-Zi; Wang, Haijiang
2015-09-16
Polyolefin membranes are widely used as separators in commercialized Li-ion batteries. They have less polarized surfaces compared with polarized molecules of electrolyte, leading to a poor wetting state for separators. Radiation pretreatments are often adopted to solve such a problem. Unfortunately, they can only activate several nanometers deep from the surface, which limits the performance improvement. Here we report a facile and scalable method to polarize polyolefin membranes via a chemical oxidation route. On the surfaces of pretreated membrane, layers of poly(ethylene oxide) and poly(acrylic acid) can easily be coated, thus resulting in a high Li-ion conductivity of the membrane. Assembled with this decorated separator in button cells, both high-voltage (Li1.2Mn0.54Co0.13Ni0.13O2) and moderate-voltage (LiFePO4) cathode materials show better electrochemical performances than those assembled with pristine polyolefin separators.
Richard, Gontran; Touhami, Seddik; Zeghloul, Thami; Dascalescu, Lucien
2017-02-01
Plate-type electrostatic separators are commonly employed for the selective sorting of conductive and non-conductive granular materials. The aim of this work is to identify the optimal operating conditions of such equipment, when employed for separating copper and plastics from either flexible or rigid electric wire wastes. The experiments are performed according to the response surface methodology, on samples composed of either "calibrated" particles, obtained by manually cutting of electric wires at a predefined length (4mm), or actual machine-grinded scraps, characterized by a relatively-wide size distribution (1-4mm). The results point out the effect of particle size and shape on the effectiveness of the electrostatic separation. Different optimal operating conditions are found for flexible and rigid wires. A separate processing of the two classes of wire wastes is recommended. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Li, Hao; Niu, Dong-Hui; Zhou, Hui; Chao, Chun-Ying; Wu, Li-Jun; Han, Pei-Lin
2018-05-01
Hydroxyl-terminated polybutadiene grafted methoxyl polyethylene glycol (HTPB-g-MPEG) with different arm length were synthesized by grafting methoxyl poly(ethylene glycol)s (MPEGs, Mn = 350, 750, 1900 and 5000, respectively) to the hydroxyl-terminated polybutadiene (HTPB) molecule using isophorone diisocyanate (IPDI) as the coupling agent, and blended with PVDF to fabricate porous separators via phase inversion process. By measuring the composition, morphology and ion conductivity etc., the influence of HTPB-g-MPEG on structure and property of blend separators were discussed. Compared with pure PVDF separator with comparable porous structure, the adoption of HTPB-g-MPEG could not only decrease the crystallinity, but also enhance the stability of entrapped liquid electrolyte and corresponding ion conductivity. The cells assembled with such separators showed good initial discharge capacity and cyclic stability.
On Leakage Current Measured at High Cell Voltages in Lithium-Ion Batteries
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vadivel, Nicole R.; Ha, Seungbum; He, Meinan
2017-01-01
In this study, parasitic side reactions in lithium-ion batteries were examined experimentally using a potentiostatic hold at high cell voltage. The experimental leakage current measured during the potentiostatic hold was compared to the Tafel expression and showed poor agreement with the expected transfer coefficient values, indicating that a more complicated expression could be needed to accurately capture the physics of this side reaction. Here we show that cross-talk between the electrodes is the primary contribution to the observed leakage current after the relaxation of concentration gradients has ceased. This cross-talk was confirmed with experiments using a lithium-ion conducting glass ceramicmore » (LICGC) separator, which has high conductance only for lithium cations. The cells with LICGC separators showed significantly less leakage current during the potentiostatic hold test compared to cells with standard microporous separators where cross-talk is present. In addition, direct-current pulse power tests show an impedance rise for cells held at high potentials and for cells held at high temperatures, which could be attributed to film formation from the parasitic side reaction. Based on the experimental findings, a phenomenological mechanism is proposed for the parasitic side reaction which accounts for cross-talk and mass transport of the decomposition products across the separator.« less
NASA Astrophysics Data System (ADS)
Hayashi, S.; Mishima, F.; Akiyama, Y.; Nishijima, S.
2010-11-01
In the industrial plants processing highly viscous fluid such as foods or industrial materials, there is an issue of contamination by metallic wear debris originating from pipe of manufacturing line. It is necessary to remove the metallic wear debris in highly viscous fluid, since these debris causes quality loss. In this study, we developed a high gradient magnetic separation system by using superconducting magnet to remove the metallic wear debris. The particle trajectory simulation and the magnetic separation experiment were conducted with polyvinyl alcohol as a model material. As a result, ca. 100% and 92.2% of the separation efficiency was achieved respectively for the highly viscous fluid of 1 Pa s and 6 Pa s in viscosity, with 14 and 30 mesh magnetic filters.
A Flight Deck Perspective of Self-Separation
NASA Technical Reports Server (NTRS)
Lozito, Sandra; Rosekind, Mark (Technical Monitor)
1997-01-01
I will be participating on a Free Flight Human Factors Panel at the Ninth International Symposium on Aviation Psychology in Columbus, Ohio. My representation is related to the work that our group has conducted on flight deck issues associate with free flight. Our group completed a full-mission simulation study investigating procedural issues associated with airborne self-separation. Ten crews flew eight scenarios each in the B747-400 simulator at Ames. Each scenario had a representation of different conflict geometries with intruder aircraft. New alerting logic was created and integrated into the simulator to enable self-separation. In addition, new display features were created to help provide for enhanced information to the flight crew about relevant aircraft, The participants were asked to coordinate maneuvers for self-separation with the intruder aircraft. Data analyses for the many of the crew procedures have been completed.
District-Wide Comprehensive Needs Assessment Study: Administrator Levels Report, Part II, 1980-81.
ERIC Educational Resources Information Center
Saginaw Public Schools, MI. Dept. of Evaluation Services.
A needs assessment study was conducted to identify areas of consensus for respondent groups concerning attitudes toward educational issues. The overall findings of all respondents and each respondent group separately was presented. The groups were elementary, junior high, senior high, and central office administrators. Opinions of these groups are…
Extending the Conceptualization of Listening Fidelity
ERIC Educational Resources Information Center
Fitch-Hauser, Margaret; Powers, William G.; O'Brien, Kelley; Hanson, Scott
2007-01-01
An exploration of variables potentially related to Listening Fidelity (LF) was conducted through two separate studies. Study 1 indicated that when the potential fidelity of the stimulus message was varied as a function of the number of words and time length, the message with lowest potential fidelity produced significantly lower LF than either the…
Benefits of Service-Learning for Freshmen College Students and Elementary School Children
ERIC Educational Resources Information Center
Eppler, Marion A.; Ironsmith, Marsha; Dingle, Stephanie H.; Errickson, Marissa A.
2011-01-01
Freshman honors students in a service-learning course tutored low-income English Language Learning kindergartners, first-, and second-graders in reading. We conducted two separate data collections, one assessing college students' attitudes and motives (Study 1) and one exploring the benefits for elementary school children (Study 2). We measured…
Research studies with the International Ultraviolet Explorer
NASA Technical Reports Server (NTRS)
1991-01-01
The IUE research studies comprises 118 separate research programs involving observations, data analysis, and research conducted of the IUE satellite and the NASA Astrophysics Data Program. Herein are presented 92 programs. For each program there is a title, program ID, name of the investigator, statement of work, summary of results, and list of publications.
Aircraft and avionic related research required to develop an effective high-speed runway exit system
NASA Technical Reports Server (NTRS)
Schoen, M. L.; Hosford, J. E.; Graham, J. M., Jr.; Preston, O. W.; Frankel, R. S.; Erickson, J. B.
1979-01-01
Research was conducted to increase airport capacity by studying the feasibility of the longitudinal separation between aircraft sequences on final approach. The multidisciplinary factors which include the utility of high speed exits for efficient runway operations were described along with recommendations and highlights of these studies.
ERIC Educational Resources Information Center
Schertz, Hannah H.; Call-Cummings, Meagan; Horn, Kathryn; Quest, Kelsey; Law, Rhiannon Steffen
2018-01-01
A qualitative study of three parents and their toddlers with autism was conducted to investigate the communicative functions underlying parent-toddler interactions and how the instrumental or social nature of one partner's actions influenced the other's engagement. Parent-child interaction videos collected from a separate intervention study were…
NASA Astrophysics Data System (ADS)
Ismail, M. A.; Mohamad, N. F.; Ilias, M. R.; Shafie, S.
2017-09-01
Magnetohydrodynamic (MHD) effect is a study on motion of electrical-conducting fluid under magnetic fields. This effect has great intention due to its applications such as design of heat exchanger and nuclear reactor. In the problem in fluid motion, flow of separation can reduced the effectiveness of the system as well as can increased the energy lost. This study will present the results on reducing the flow separation by considering magnetic effect. In this study, unsteady mixed convection boundary layer flow past a circular cylinder is given attention. Focus of study is on the separation times that affected by the magnetic fields. The mathematical models in the form of partial differential equations are transformed into nonlinear coupled ordinary differential equations and solved numerically using an implicit finite-difference scheme known as Keller-box method. The effect of magnetic parameter on velocity and temperature profiles as well as skin friction and Nusselt number are studied.
Ultracapacitor current collector
Jerabek, Elihu Calfin; Mikkor, Mati
2001-10-16
An ultracapacitor having 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. At least one of the current collectors comprises a conductive metal substrate coated with a metal nitride, carbide or boride coating.
NASA Technical Reports Server (NTRS)
Wojciechowski, C. J.; Penny, M. M.; Prozan, R. J.
1970-01-01
The results are presented of a space shuttle plume impingement study for the Manned Spacecraft Center configuration. This study was conducted as two tasks which were to (1) define the orbiter main stage engine exhaust plume flow field, and (2) define the plume impingement heating, force and resulting moment environments on the booster during the staging maneuver. To adequately define these environments during the staging maneuver and allow for deviation from the nominal separation trajectory, a multitude of relative orbiter/booster positions are analyzed which map the region that contains the separation trajectories. The data presented can be used to determine a separation trajectory which will result in acceptable impingement heating rates, forces, and the resulting moments. The data, presented in graphical form, include the effect of roll, pitch and yaw maneuvers for the booster. Quasi-steady state analysis methods were used with the orbiter engine operating at full thrust. To obtain partial thrust results, simple ratio equations are presented.
Copper Multiwall Carbon Nanotubes and Copper-Diamond Composites for Advanced Rocket Engines
NASA Technical Reports Server (NTRS)
Bhat, Biliyar N.; Ellis, Dave L.; Smelyanskiy, Vadim; Foygel, Michael; Singh, Jogender; Rape, Aaron; Vohra, Yogesh; Thomas, Vinoy; Li, Deyu; Otte, Kyle
2013-01-01
This paper reports on the research effort to improve the thermal conductivity of the copper-based alloy NARloy-Z (Cu-3 wt.%Ag-0.5 wt.% Zr), the state-of-the-art alloy used to make combustion chamber liners in regeneratively-cooled liquid rocket engines, using nanotechnology. The approach was to embed high thermal conductivity multiwall carbon nanotubes (MWCNTs) and diamond (D) particles in the NARloy-Z matrix using powder metallurgy techniques. The thermal conductivity of MWCNTs and D have been reported to be 5 to 10 times that of NARloy-Z. Hence, 10 to 20 vol. % MWCNT finely dispersed in NARloy-Z matrix could nearly double the thermal conductivity, provided there is a good thermal bond between MWCNTs and copper matrix. Quantum mechanics-based modeling showed that zirconium (Zr) in NARloy-Z should form ZrC at the MWCNT-Cu interface and provide a good thermal bond. In this study, NARloy-Z powder was blended with MWCNTs in a ball mill, and the resulting mixture was consolidated under high pressure and temperature using Field Assisted Sintering Technology (FAST). Microstructural analysis showed that the MWCNTs, which were provided as tangles of MWCNTs by the manufacturer, did not detangle well during blending and formed clumps at the prior particle boundaries. The composites made form these powders showed lower thermal conductivity than the base NARloy-Z. To eliminate the observed physical agglomeration, tangled multiwall MWCNTs were separated by acid treatment and electroless plated with a thin layer of chromium to keep them separated during further processing. Separately, the thermal conductivities of MWCNTs used in this work were measured, and the results showed very low values, a major factor in the low thermal conductivity of the composite. On the other hand, D particles embedded in NARloy-Z matrix showed much improved thermal conductivity. Elemental analysis showed migration of Zr to the NARloy-Z-D interface to form ZrC, which appeared to provide a low contact thermal resistance. These results are consistent with the quantum mechanics-based model predictions. NARloy-Z-D composites have relatively high thermal conductivities and are promising for further development.
Copper-Multiwall Carbon Nanotubes and Copper-Diamond Composites for Advanced Rocket Engines
NASA Technical Reports Server (NTRS)
Bhat, Biliyar N.; Ellis, Dave L.; Smelyanskiy, Vadim; Foygel, Michael; Rape, Aaron; Singh, Jogender; Vohra, Yogesh K.; Thomas, Vinoy; Otte, Kyle G.; Li, Deyu
2013-01-01
This paper reports on the research effort to improve the thermal conductivity of the copper-based alloy NARloy-Z (Cu-3 wt.%Ag-0.5 wt.% Zr), the state-of-the-art alloy used to make combustion chamber liners in regeneratively-cooled liquid rocket engines, using nanotechnology. The approach was to embed high thermal conductivity multiwall carbon nanotubes (MWCNTs) and diamond (D) particles in the NARloy-Z matrix using powder metallurgy techniques. The thermal conductivity of MWCNTs and D have been reported to be 5 to 10 times that of NARloy-Z. Hence, 10 to 20 vol. % MWCNT finely dispersed in NARloy-Z matrix could nearly double the thermal conductivity, provided there is a good thermal bond between MWCNTs and copper matrix. Quantum mechanics-based modeling showed that zirconium (Zr) in NARloy-Z should form ZrC at the MWCNT-Cu interface and provide a good thermal bond. In this study, NARloy-Z powder was blended with MWCNTs in a ball mill, and the resulting mixture was consolidated under high pressure and temperature using Field Assisted Sintering Technology (FAST). Microstructural analysis showed that the MWCNTs, which were provided as tangles of MWCNTs by the manufacturer, did not detangle well during blending and formed clumps at the prior particle boundaries. The composites made form these powders showed lower thermal conductivity than the base NARloy-Z. To eliminate the observed physical agglomeration, tangled multiwall MWCNTs were separated by acid treatment and electroless plated with a thin layer of chromium to keep them separated during further processing. Separately, the thermal conductivities of MWCNTs used in this work were measured, and the results showed very low values, a major factor in the low thermal conductivity of the composite. On the other hand, D particles embedded in NARloy-Z matrix showed much improved thermal conductivity. Elemental analysis showed migration of Zr to the NARloy-Z-D interface to form ZrC, which appeared to provide a low contact thermal resistance. These results are consistent with the quantum mechanics-based model predictions. NARloy-Z-D composites have relatively high thermal conductivities and are promising for further development.
EXFILTRATION IN SEWER SYSTEMS: IS IT A NATIONAL PROBLEM?
Many municipalities throughout the US have sewerage systems (separate and combined) that may experience exfiltration of untreated wastewater. This study was conducted to focus on the magnitude of the exfiltration problem from sewer pipes on a national basis. The method for estima...
EXFILTRATION IN SANITARY SEWER SYSTEMS IN THE U.S.
Many municipalities throughout the US have sewerage systems (separate and combined) that may experience exfiltration of untreated wastewater. This study was conducted to focus on the magnitude of the exfiltration problem from sewer pipes on a national basis. The method for estima...
INDOOR AIR QUALITY IN PUBLIC BUILDINGS. VOLUME 2
Two separate but closely related studies of exposures to volatile organic compounds (VOCs) in buildings where people spend long periods of time were conducted. The report summarizes results obtained in six buildings: a new hospital, office and nursing home and another office, off...
A high performance ceramic-polymer separator for lithium batteries
NASA Astrophysics Data System (ADS)
Kumar, Jitendra; Kichambare, Padmakar; Rai, Amarendra K.; Bhattacharya, Rabi; Rodrigues, Stanley; Subramanyam, Guru
2016-01-01
A three-layered (ceramic-polymer-ceramic) hybrid separator was prepared by coating ceramic electrolyte [lithium aluminum germanium phosphate (LAGP)] over both sides of polyethylene (PE) polymer membrane using electron beam physical vapor deposition (EB-PVD) technique. Ionic conductivities of membranes were evaluated after soaking PE and LAGP/PE/LAGP membranes in a 1 Molar (1M) lithium hexafluroarsenate (LiAsF6) electrolyte in ethylene carbonate (EC), dimethyl carbonate (DMC) and ethylmethyl carbonate (EMC) in volume ratio (1:1:1). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques were employed to evaluate morphology and structure of the separators before and after cycling performance tests to better understand structure-property correlation. As compared to regular PE separator, LAGP/PE/LAGP hybrid separator showed: (i) higher liquid electrolyte uptake, (ii) higher ionic conductivity, (iii) lower interfacial resistance with lithium and (iv) lower cell voltage polarization during lithium cycling at high current density of 1.3 mA cm-2 at room temperature. The enhanced performance is attributed to higher liquid uptake, LAGP-assisted faster ion conduction and dendrite prevention. Optimization of density and thickness of LAGP layer on PE or other membranes through manipulation of PVD deposition parameters will enable practical applications of this novel hybrid separator in rechargeable lithium batteries with high energy, high power, longer cycle life, and higher safety level.
Methods of Using a Magnetic Field Response Sensor Within Closed, Electrically Conductive Containers
NASA Technical Reports Server (NTRS)
Woodward, Stanley E.; Taylor, Bryant D.
2010-01-01
Magnetic field response sensors are a class of sensors that are powered via oscillating magnetic fields, and when electrically active, respond with their own magnetic fields with attributes dependent upon the magnitude of the physical quantity being measured. A magnetic field response recorder powers and interrogates the magnetic sensors [see Magnetic-Field-Response Measurement- Acquisition System, NASA Tech Briefs Vol. 30, No, 6 (June 2006, page 28)]. Electrically conductive containers have low transmissivity for radio frequency (RF) energy and thus present problems for magnetic field response sensors. It is necessary in some applications to have a magnetic field response sensor s capacitor placed in these containers. Proximity to conductive surfaces alters the inductance and capacitance of the sensors. As the sensor gets closer to a conductive surface, the electric field and magnetic field energy of the sensor is reduced due to eddy currents being induced in the conductive surface. Therefore, the capacitors and inductors cannot be affixed to a conductive surface or embedded in a conductive material. It is necessary to have a fixed separation away from the conductive material. The minimum distance for separation is determined by the desired sensor response signal to noise ratio. Although the inductance is less than what it would be if it were not in proximity to the conductive surface, the inductance is fixed. As long as the inductance is fixed, all variations of the magnetic field response are due to capacitance changes. Numerous variations of inductor mounting can be utilized, such as providing a housing that provides separation from the conductive material as well as protection from impact damage. The sensor can be on the same flexible substrate with a narrow throat portion of the sensor between the inductor and the capacitor, Figure 1. The throat is of sufficient length to allow the capacitor to be appropriately placed within the container and the inductor placed outside the container. The throat is fed through the orifice in the container wall (e.g., fuel tank opening) and connects to the inductor and capacitor via electrical leads to form a closed circuit, Figure 2. Another embodiment is to have the inductor and capacitor fabricated as separate units. In this embodiment, the inductor is mounted external to the container, and the capacitor is mounted internal to the container, Figure 1. Electrical leads are fed through the orifice to connect the inductor and capacitor, Figure 2. When a container holding multiple sensors is made of a conductive material, an antenna can be placed internal to the container. An internal antenna allows all components of the sensors to reside inside the container. The antenna must be separated from the container wall s conductive surface. Additionally, the inductors must be maintained in a fixed position relative to and separated from the container
Waldron, Mary; Vaughan, Ellen L.; Bucholz, Kathleen K.; Lynskey, Michael T.; Sartor, Carolyn E.; Duncan, Alexis E.; Madden, Pamela A.F.; Heath, Andrew C.
2014-01-01
Background We examined timing of substance involvement as a joint function of parental history of alcoholism and parental separation during childhood. Method Data were drawn from a large cohort of female like-sex twins [n = 613 African Ancestry (AA), n = 3550 European or other Ancestry (EA)]. Cox proportional hazards regression was conducted predicting age at first use of alcohol, first alcohol intoxication, first use and regular use of cigarettes, and first use of cannabis and other illicit drugs from dummy variables coding for parental alcoholism and parental separation. Propensity score analysis was also conducted comparing intact and separated families by predicted probability of parental separation. Results In EA families, increased risk of substance involvement was found in both alcoholic and separated families, particularly through ages 10 or 14 years, with risk to offspring from alcoholic separated families further increased. In AA families, associations with parental alcoholism and parental separation were weak and with few exceptions statistically nonsignificant. While propensity score findings confirmed unique risks observed in EA families, intact and separated AA families were poorly matched on risk-factors presumed to predate parental separation, especially parental alcoholism, requiring cautious interpretation of AA survival-analytic findings. Conclusion For offspring of European ancestry, parental separation predicts early substance involvement that is not explained by parental alcoholism nor associated family background characteristics. Additional research is needed to better characterize risks associated with parental separation in African American families. PMID:24647368
Waldron, Mary; Vaughan, Ellen L; Bucholz, Kathleen K; Lynskey, Michael T; Sartor, Carolyn E; Duncan, Alexis E; Madden, Pamela A F; Heath, Andrew C
2014-05-01
We examined timing of substance involvement as a joint function of parental history of alcoholism and parental separation during childhood. Data were drawn from a large cohort of female like-sex twins [n=613 African Ancestry (AA), n=3550 European or other ancestry (EA)]. Cox proportional hazards regression was conducted predicting age at first use of alcohol, first alcohol intoxication, first use and regular use of cigarettes, and first use of cannabis and other illicit drugs from dummy variables coding for parental alcoholism and parental separation. Propensity score analysis was also conducted comparing intact and separated families by predicted probability of parental separation. In EA families, increased risk of substance involvement was found in both alcoholic and separated families, particularly through ages 10 or 14 years, with risk to offspring from alcoholic separated families further increased. In AA families, associations with parental alcoholism and parental separation were weak and with few exceptions statistically nonsignificant. While propensity score findings confirmed unique risks observed in EA families, intact and separated AA families were poorly matched on risk-factors presumed to predate parental separation, especially parental alcoholism, requiring cautious interpretation of AA survival-analytic findings. For offspring of European ancestry, parental separation predicts early substance involvement that is not explained by parental alcoholism nor associated family background characteristics. Additional research is needed to better characterize risks associated with parental separation in African American families. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reimus, Paul William
A two-part field study was conducted in Smith Ranch-Highland in-situ recovery (ISR) near Douglas, Wyoming, to evaluate the restorative capacity of the aquifer downgradient (i.e., hydrologically downstream) of a Uranium ISR mining site with respect to the transport of uranium and other potential contaminants in groundwater after mining has ceased. The study was partially conducted by checking the Uranium content and the alkalinity of separate wells, some wells had been restored and others had not. A map and in-depth procedures of the study are included.
The application of electrical conductivity as a tracer for hydrograph separation in urban catchments
Pellerin, B.A.; Wollheim, W.M.; Feng, X.; Vororsmarty, C.J.
2008-01-01
Two-component hydrograph separation was performed on 19 low-to-moderate intensity rainfall events in a 4.1-km2 urban watershed to infer the relative and absolute contribution of surface runoff (e.g. new water) to stormflow generation between 2001 and 2003. The electrical conductivity (EC) of water was used as a continuous and inexpensive tracer, with order of magnitude differences in precipitation (12-46 ??S/cm) and pre-event streamwater EC values (520-1297 ??S/cm). While new water accounted for most of the increased discharge during storms (61-117%), the contribution of new water to total discharge during events was typically lower (18-78%) and negatively correlated with antecedent stream discharge (r2 = 0??55, p < 0??01). The amount of new water was positively correlated with total rainfall (r2 = 0??77), but hydrograph separation results suggest that less than half (9-46%) of the total rainfall on impervious surfaces is rapidly routed to the stream channel as new water. Comparison of hydrograph separation results using non-conservative tracers (EC and Si) and a conservative isotopic tracer (??D) for two events showed similar results and highlighted the potential application of EC as an inexpensive, high frequency tracer for hydrograph separation studies in urban catchments. The use of a simple tracer-based approach may help hydrologists and watershed managers to better understand impervious surface runoff, stormflow generation and non-point-source pollutant loading to urban streams. Copyright ?? 2007 John Wiley & Sons, Ltd.
Aquagel electrode separator for use in batteries and supercapacitors
Mayer, S.T.; Kaschmitter, J.L.; Pekala, R.W.
1995-03-28
An electrode separator is described for electrochemical energy storage devices, such as a high energy density capacitor incorporating a variety of carbon foam electrodes. The separator is derived from an aquagel of resorcinol-formaldehyde and related polymers and containing ionically conducting electrolyte in the pores thereof. 9 figures.
Tudur Smith, Catrin; Gueyffier, François; Kolamunnage‐Dona, Ruwanthi
2017-01-01
Background Joint modelling of longitudinal and time‐to‐event data is often preferred over separate longitudinal or time‐to‐event analyses as it can account for study dropout, error in longitudinally measured covariates, and correlation between longitudinal and time‐to‐event outcomes. The joint modelling literature focuses mainly on the analysis of single studies with no methods currently available for the meta‐analysis of joint model estimates from multiple studies. Methods We propose a 2‐stage method for meta‐analysis of joint model estimates. These methods are applied to the INDANA dataset to combine joint model estimates of systolic blood pressure with time to death, time to myocardial infarction, and time to stroke. Results are compared to meta‐analyses of separate longitudinal or time‐to‐event models. A simulation study is conducted to contrast separate versus joint analyses over a range of scenarios. Results Using the real dataset, similar results were obtained by using the separate and joint analyses. However, the simulation study indicated a benefit of use of joint rather than separate methods in a meta‐analytic setting where association exists between the longitudinal and time‐to‐event outcomes. Conclusions Where evidence of association between longitudinal and time‐to‐event outcomes exists, results from joint models over standalone analyses should be pooled in 2‐stage meta‐analyses. PMID:29250814
Detection of non-protein amino acids in the presence of protein amino acids. II.
NASA Technical Reports Server (NTRS)
Shapshak, P.; Okaji, M.
1972-01-01
Studies conducted with the JEOL 5AH amino acid analyzer are described. This instrument makes possible the programming of the chromatographic process. Data are presented showing the separations of seventeen non-protein amino acids in the presence of eighteen protein amino acids. It is pointed out that distinct separations could be obtained in the case of a number of chemically similar compounds, such as ornithine and lysine, N-amidino alanine and arginine, and iminodiacetic acid and S-carboxymethyl cysteine and aspartic acid.
Alternating current conduction studies on polypyrrole-iron nanocomposite at room temperature
NASA Astrophysics Data System (ADS)
Kumar, T. G. Naveen; Megha, R.; Revanasiddappa, M.; Ravikiran, Y. T.; Kumari, S. C. Vijaya
2018-05-01
In the present work, Polypyrrole (PPy) and Polypyrrole-Iron (PPy-Fe) nanocomposite were synthesized separately by chemical polymerisation method and then they were structurally characterised by Fourier transform infrared spectroscopy (FTIR) and Transmission electron microscopy (TEM) techniques. The alternate current (AC) response characteristics at room temperature of PPy and the composite were comparatively studied in the frequency range 100Hz-1MHz. The real part of conductivities of both PPy and the composite were interpreted as power law of frequency and the frequency exponent s was found to lie in the range 0< s<1 in both the cases. The nanocomposite has shown significant improvement in conductivity as compared to PPy.
CTEPP STANDARD OPERATING PROCEDURE FOR CONDUCTING STAFF AND PARTICIPANT TRAINING (SOP-2.27)
This SOP describes the method to train project staff and participants to collect various field samples and questionnaire data for the study. The training plan consists of two separate components: project staff training and participant training. Before project activities begin,...
MULTI-SITE FIELD EVALUATION OF CANDIDATE SAMPLERS FOR MEASURING COARSE-MODE PM
In response to expected changes to the National Ambient Air Quality Standards for particulate matter, comprehensive field studies were conducted to evaluate the performance of sampling methods for measuring coarse mode aerosols (i.e. PMc). Five separate PMc sampling approaches w...
Filtration and clogging of permeable pavement loaded by urban drainage.
Sansalone, J; Kuang, X; Ying, G; Ranieri, V
2012-12-15
Permeable pavement, as a sustainable infrastructure material can promote hydrologic restoration, particulate matter (PM) and solute control. However, filtration and commensurate clogging are two aspects of continued interest and discussion. This study quantifies filtration and clogging of cementitious permeable pavement (CPP) for loadings from 50 to 200 mg/L of hetero-disperse sandy-silt PM. The CPP mix design provides a hetero-disperse pore size distribution (PSD)(pore), effective porosity (φ(e)) of 24% and median pore size of 658 μm with a standard deviation of 457 μm. The PM mass separation across the entire particle size distribution (PSD)(PM) exceeds 80%; with complete separation for PM greater than 300 μm and 50% separation for suspended PM. Turbidity is reduced (42-95%), and effluent is below 10 NTU in the first quartile of a loading period. Permeable pavement illustrates reductions in initial (clean-bed) hydraulic conductivity (k(0)) with loading time. For all PM loadings, k(0) (3.1 × 10(-1) mm/s) was reduced to 10(-4) mm/s for runoff loading durations from 100 to 250 h, respectively. Temporal hydraulic conductivity (k) follows exponential profiles. Maintenance by vacuuming and sonication illustrate that 96-99% of k(0) is recovered. Permeable pavement constitutive properties integrated with measured PM loads and a year of continuous rainfall-runoff simulation illustrate k reduction with historical loadings. Study results measure and model filtration and hydraulic conductivity phenomena as well as maintenance requirements of permeable pavement directly loaded by urban drainage. Copyright © 2011. Published by Elsevier Ltd.
Sanford, Ward E.; Nelms, David L.; Pope, Jason P.; Selnick, David L.
2012-01-01
This study by the U.S. Geological Survey, prepared in cooperation with the Virginia Department of Environmental Quality, quantifies the components of the hydrologic cycle across the Commonwealth of Virginia. Long-term, mean fluxes were calculated for precipitation, surface runoff, infiltration, total evapotranspiration (ET), riparian ET, recharge, base flow (or groundwater discharge) and net total outflow. Fluxes of these components were first estimated on a number of real-time-gaged watersheds across Virginia. Specific conductance was used to distinguish and separate surface runoff from base flow. Specific-conductance data were collected every 15 minutes at 75 real-time gages for approximately 18 months between March 2007 and August 2008. Precipitation was estimated for 1971–2000 using PRISM climate data. Precipitation and temperature from the PRISM data were used to develop a regression-based relation to estimate total ET. The proportion of watershed precipitation that becomes surface runoff was related to physiographic province and rock type in a runoff regression equation. Component flux estimates from the watersheds were transferred to flux estimates for counties and independent cities using the ET and runoff regression equations. Only 48 of the 75 watersheds yielded sufficient data, and data from these 48 were used in the final runoff regression equation. The base-flow proportion for the 48 watersheds averaged 72 percent using specific conductance, a value that was substantially higher than the 61 percent average calculated using a graphical-separation technique (the USGS program PART). Final results for the study are presented as component flux estimates for all counties and independent cities in Virginia.
Du, Fei-Peng; Cao, Nan-Nan; Zhang, Yun-Fei; Fu, Ping; Wu, Yan-Guang; Lin, Zhi-Dong; Shi, Run; Amini, Abbas; Cheng, Chun
2018-04-24
The typical conductive polymer of PEDOT:PSS has recently attracted intensive attention in thermoelectric conversion because of its low cost and low thermal conductivity as well as high electrical conductivity. However, compared to inorganic counterparts, the relatively poor thermoelectric performance of PEDOT:PSS has greatly limited its development and high-tech applications. Here, we report a dramatic enhancement in the thermoelectric performance of PEDOT:PSS by constructing unique composite films with graphene quantum dots (GQDs). At room temperature, the electrical conductivity and Seebeck coefficient of PEDOT:PSS/GQDs reached to 7172 S/m and 14.6 μV/K, respectively, which are 30.99% and 113.2% higher than those of pristine PEDOT:PSS. As a result, the power factor of the optimized PEDOT:PSS/GQDs composite is 550% higher than that of pristine PEDOT:PSS. These significant improvements are attributed to the ordered alignment of PEDOT chains on the surface of GQDs, originated from the strong interfacial interaction between PEDOT:PSS and GQDs and the separation of PEDOT and PSS phases. This study evidently provides a promising route for PEDOT:PSS applied in high-efficiency thermoelectric conversion.
5 CFR 3801.103 - Designation of separate Departmental components.
Code of Federal Regulations, 2010 CFR
2010-01-01
... OF ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF JUSTICE § 3801.103 Designation of separate... Enforcement Administration Environment and Natural Resources Division Executive Office for Immigration Review...
ERIC Educational Resources Information Center
Benjamin, Ludy T., Jr.; Simpson, Jeffry A.
2009-01-01
Few psychological studies, if any, can claim a legacy as imposing as the obedience studies of Stanley Milgram. Their impact was of notable consequence in the separate spheres of research ethics, research design, and theory in psychology, and they changed the ways that psychologists conceptualize and conduct their research. The authors discuss the…
DESIGN AND DEVELOPMENT OF GAS-LIQUID CYLINDRICAL CYCLONE COMPACT SEPARATORS FOR THREE-PHASE FLOW
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dr. Ram S. Mohan; Dr. Ovadia Shoham
The U.S. Department of Energy (DOE) has awarded a five-year (1997-2002) grant (Mohan and Shoham, DE-FG26-97BC15024, 1997) to The University of Tulsa, to develop compact multiphase separation components for 3-phase flow. The research activities of this project have been conducted through cost sharing by the member companies of the Tulsa University Separation Technology Projects (TUSTP) research consortium and the Oklahoma Center for the Advancement of Science and Technology (OCAST). As part of this project, several individual compact separation components have been developed for onshore and offshore applications. These include gas-liquid cylindrical cyclones (GLCC{copyright}), liquid-liquid cylindrical cyclones (LLCC{copyright}), and the gas-liquid-liquidmore » cylindrical cyclones (GLLCC{copyright}). A detailed study has also been completed for the liquid-liquid hydrocyclones (LLHC). Appropriate control strategies have been developed for proper operation of the GLCC{copyright} and LLCC{copyright}. Testing of GLCC{copyright} at high pressure and real crude conditions for field applications is also completed. Limited studies have been conducted on flow conditioning devices to be used upstream of the compact separators for performance improvement. This report presents a brief overview of the activities and tasks accomplished during the 5-year project period, October 1, 1997-March 31, 2003 (including the no-cost extended period of 6 months). An executive summary is presented initially followed by the tasks of the 5-year budget periods. Then, detailed description of the experimental and modeling investigations are presented. Subsequently, the technical and scientific results of the activities of this project period are presented with some discussions. The findings of this investigation are summarized in the ''Conclusions'' section, followed by relevant references. The publications resulting from this study in the form of MS Theses, Ph.D. Dissertation, Journal Papers and Conference Presentations are provided at the end of this report.« less
Di Manno, Laura; Macdonald, Jacqui A; Knight, Tess
2015-12-01
Parental separation is associated with increased risk for offspring depression; however, depression outcomes are divergent. Knowledge of moderators could assist in understanding idiosyncratic outcomes and developing appropriately targeted prevention programs for those at heightened risk of depression following parental separation. Therefore, the objective of the review was to identify and evaluate studies that examined moderators of the relationship between parental separation and offspring depression A search of scientific, medical and psychological databases was conducted in April 2015 for longitudinal research that had evaluated any moderator/s of the relationship between parental separation or divorce and offspring depression or depressive symptoms. Papers were assessed for quality by evaluating the study's sample, attrition rates, methodology and measurement characteristics. Fourteen quantitative studies from five countries assessed sixteen moderating factors of the relationship between parental separation and offspring depression or depressive symptoms. A number of factors were found to moderate this relationship, including offspring gender, age (at assessment and at depression onset), genotype, preadolescent temperament, IQ, emotional problems in childhood and maternal sensitivity. While robust longitudinal research was selected for inclusion, common issues with longitudinal studies such as low rates of participation and attrition were among the methodological concerns evident in some of the reviewed papers. The current review is the first to assess interaction effects of the relationship between parental separation and offspring depression or depressive symptoms. While further research is recommended, this assessment is critical in understanding variation in heterogeneous populations and can inform targeted policy and prevention.
A review of the use of vortex generators for mitigating shock-induced separation
NASA Astrophysics Data System (ADS)
Titchener, Neil; Babinsky, Holger
2015-09-01
This article reviews research into the potential of vortex generators to mitigate shock-induced separation. Studies ranging from those conducted in the early post-war era to those performed recently are discussed. On the basis of the investigations described in this report, it is clear that vortex generators can alleviate shock-induced boundary layer separation. Yet, it will be shown that their potential and efficiency varies considerably in practical applications. Much more success is reported in transonic test cases compared to separation induced in purely supersonic interactions. Under a variety of flow conditions, the best performance is achieved with vortex generators with a height of roughly half the boundary layer thickness and a shape similar to a swept vane. Notwithstanding this, vortex generator performance is not as consistent as it is in low-speed applications. Further work is required before vortex generators can be implemented into the design process for eliminating shock-induced separation on transonic wings and in supersonic inlets.
Recovery of PET from packaging plastics mixtures by wet shaking table.
Carvalho, M T; Agante, E; Durão, F
2007-01-01
Recycling requires the separation of materials appearing in a mass of wastes of heterogeneous composition and characteristics, into single, almost pure, component/material flows. The separation of materials (e.g., some types of plastics) with similar physical properties (e.g., specific gravity) is often accomplished by human sorting. This is the case of the separation of packaging plastics in municipal solid wastes (MSW). The low cost of virgin plastics and low value of recycled plastics necessitate the utilization of low cost techniques and processes in the recycling of packaging plastics. An experimental study was conducted to evaluate the feasibility of production of a PET product, cleaned from PVC and PS, using a wet shaking table. The wet shaking table is an environmentally friendly process, widely used to separate minerals, which has low capital and operational costs. Some operational variables of the equipment, as well as different feed characteristics, were considered. The results show that the separation of these plastics is feasible although, similarly to the mineral field, in somewhat complex flow sheets.
Savic, Michael; Chur-Hansen, Anna; Mahmood, Mohammad Afzal; Moore, Vivienne
2013-08-01
This study explored the impact of separation from family members on the mental health and wellbeing of Sudanese refugees in Australia, and the coping strategies used. In-depth interviews were conducted with Sudanese community representatives and health workers, primary and mental health care practitioners, health service managers and policy makers. Interviews were analysed using thematic analysis. Separation was perceived as having a negative impact on the mental health of Sudanese refugees in Australia, and manifested in concern about the safety of relatives abroad and in changing roles. The pressure to send money home emerged as a high priority for Sudanese refugees, often superseding local concerns. Several strategies were used to bridge the separation gap, including maintaining contact through the use of information communication technologies, and family-reunification. Separation from family can be an ongoing source of stress and sadness among refugees in countries such as Australia. While resettling refugees are actively taking steps to cope with the impact of separation, awareness of the issue in mainstream services appears to be low. Separation from family continues to affect refugees' lives in countries of resettlement. While it may be difficult to alter the course of the monumental circumstances that cause forced migration, service providers can support refugees' coping abilities by understanding these global-local intersections. © 2013 The Authors. ANZJPH © 2013 Public Health Association of Australia.
Use of the electro-separation method for improvement of the utility value of winter rapeseeds
NASA Astrophysics Data System (ADS)
Kovalyshyn, S. J.; Shvets, O. P.; Grundas, S.; Tys, J.
2013-12-01
The paper presents the results of a study of the use of electro-separation methods for improvement of the utility value of 5 winter rapeseed cultivars. The process of electro-separation of rapeseed was conducted on a prototype apparatus built at the Laboratory of Application of Electro-technologies in Agriculture, Lviv National Agriculture University. The process facilitated separation of damaged, low quality seeds from the sowing material. The initial mean level of mechanically damaged seeds in the winter rapeseed cultivars studied varied within the range of 15.8-20.1%. Verification of the amount of seeds with mechanical damage was performed on X-ray images of seeds acquired by means of a digital X-ray apparatus. In the course of analysis of the X-ray images, it was noted that the mean level of mechanical damage to the seeds after the electro-separation was in the range of 2.1-3.8%. The application of the method of separation of rapeseeds in the corona discharge field yielded a significant reduction of the level of seeds with mechanical damage. The application of the method in practice may effectively contribute to improvement of the utility value of sowing material or seed material for production of edible oil.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Jie
1999-04-01
A novel anion-exchange resin containing three amine groups was prepared by reaction of a chloromethylated polystyrene-divinylbenzene (PS-DVB) resin with diethylenetriamine. After being protonated by contact with an aqueous acid, this resin can be used for ion chromatographic separation of anions. The charge on the resins can be varied from +1 to +3 by changing the mobile phase pH. The selectivity of the new ion exchangers for various inorganic anions was quite different from that of conventional anion exchangers. The performance of this new anion exchanger was studied by changing the pH and the concentration of the eluent, and several differentmore » eluents were used with some common anions as testing analytes. Conductivity detection and UV-visible detection were applied to detect the anions after separation. The new resin can also be used for HPLC separation of neutral organic compounds. Alkylphenols and alkylbenzenes were separated with this new polymeric resin, and excellent separations were obtained under simple conditions. This report contains Chapter 1: General introduction and Chapter 6: General conclusions.« less
Gas storage carbon with enhanced thermal conductivity
Burchell, Timothy D.; Rogers, Michael Ray; Judkins, Roddie R.
2000-01-01
A carbon fiber carbon matrix hybrid adsorbent monolith with enhanced thermal conductivity for storing and releasing gas through adsorption and desorption is disclosed. The heat of adsorption of the gas species being adsorbed is sufficiently large to cause hybrid monolith heating during adsorption and hybrid monolith cooling during desorption which significantly reduces the storage capacity of the hybrid monolith, or efficiency and economics of a gas separation process. The extent of this phenomenon depends, to a large extent, on the thermal conductivity of the adsorbent hybrid monolith. This invention is a hybrid version of a carbon fiber monolith, which offers significant enhancements to thermal conductivity and potential for improved gas separation and storage systems.
5 CFR 3601.102 - Designation of separate agency components.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Service; (8) Defense Information Systems Agency; (9) Defense Intelligence Agency; (10) Defense Logistics... ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF DEFENSE § 3601.102 Designation of separate agency...
Investigation of phase separated polyimide blend films containing boron nitride using FTIR imaging
NASA Astrophysics Data System (ADS)
Chae, Boknam; Hong, Deok Gi; Jung, Young Mee; Won, Jong Chan; Lee, Seung Woo
2018-04-01
Immiscible aromatic polyimide (PI) blend films and a PI blend film incorporated with thermally conductive boron nitride (BN) were prepared, and their phase separation behaviors were examined by optical microscopy and FTIR imaging. The 2,2‧-bis(trifluoromethyl)benzidine (TFMB)-containing and 4,4‧-thiodianiline (TDA)-containing aromatic PI blend films and a PI blend/BN composite film show two clearly separated regions; one region is the TFMB-rich phase, and the other region is the TDA-rich phase. The introduction of BN induces morphological changes in the immiscible aromatic PI blend film without altering the composition of either domain. In particular, the BN is selectively incorporated into the TDA-rich phase in this study.
NASA Technical Reports Server (NTRS)
Consiglio, Maria C.; Wilson, Sara R.; Sturdy, James; Murdoch, Jennifer L.; Wing, David J.
2010-01-01
A human-in-the-loop (HITL) simulation experiment was conducted by the National Aeronautics and Space Administration (NASA) to assess airline transport pilots performance and reported acceptance of the use of procedures relying on airborne separation assistance and trajectory management tools. This study was part of a larger effort involving two NASA centers that includes multiple HITL experiments planned over the next few years to evaluate the use of automated separation assurance (SA) tools by both air traffic controllers and pilots. This paper presents results of measured pilot response delay that subject pilots incurred when interacting with cockpit tools for SA and discusses possible implications for future concept and procedures design.
A Content and Methodological Analysis of 35 Years of Latino/a-Focused Research
ERIC Educational Resources Information Center
Liang, Christopher T. H.; Salcedo, Jime; Rivera, Amanda L. Y.; Lopez, Mayra J.
2009-01-01
Two separate studies were conducted to examine the contents and methodology of Latino/a-focused articles published during a period of 35 years in seven major journals used by counseling psychologists as well as the "Hispanic Journal of Behavioral Sciences." Together, the two studies suggest that acculturation, academic achievement, assessment, and…
Development and Validation of the Job Crafting Scale
ERIC Educational Resources Information Center
Tims, Maria; Bakker, Arnold B.; Derks, Daantje
2012-01-01
We developed and validated a scale to measure job crafting behavior in three separate studies conducted in The Netherlands (total N=1181). Job crafting is defined as the self-initiated changes that employees make in their own job demands and job resources to attain and/or optimize their personal (work) goals. In Study 1 and 2 the Dutch job…
ERIC Educational Resources Information Center
Cajkler, Wasyl; Wood, Phil; Norton, Julie; Pedder, David; Xu, Haiyan
2015-01-01
Two departments in a secondary school in England participated in "lesson study" projects over a five-month period to explore its usefulness as a vehicle for professional development. Through a cycle of two research lessons, conducted separately in each department, teachers identified challenges that inhibited the learning of their…
Planning for the Elderly Without Architecture Is Like Architecture for the Elderly Without Planning
ERIC Educational Resources Information Center
Bednar, Michael; And Others
1977-01-01
A joint project between the separate divisions of planning and architecture at the UVA School of Architecture was conducted to allow graduate students to study the environmental needs of the elderly. The case-study approach was undertaken in Lynchburg, Virginia, and the year-long project was seen as a "real World" problem. (LBH)
Merchant Marine and Commuter Families: A Comparison of Couples Who Live Apart.
ERIC Educational Resources Information Center
Gross, Harriet Engel; And Others
A study compared commuter and Merchant Marine families with traditional households in order to separate effects related to living apart from those related to the career status (single vs. dual) of families. During the study researchers conducted in-depth interviews with 50 wives and 30 husbands representing 58 Merchant Marine families of whom 22…
ERIC Educational Resources Information Center
DuPaul, George J.; Eckert, Tanya L.; Vilardo, Brigid
2012-01-01
A meta-analysis evaluating the effects of school-based interventions for students with attention deficit hyperactivity disorder was conducted by examining 60 outcome studies between 1996 and 2010 that yielded 85 effect sizes. Separate analyses were performed for studies employing between-subjects, within- subjects, and single-subject experimental…
Mentors' Perceptions on the Post Mentoring Relationships in Academic Organizations
ERIC Educational Resources Information Center
Erdem, Ferda; Ömüris, Ece
2014-01-01
This qualitative study aims to reveal the new period of the relationships between the mentors and mentees who continue to work in the same academic organization after the mentoring relationship terminates. The findings of this study that was conducted in a small group of mentors who cultivated multiple mentees show that the separation phase did…
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.
Rago, Laura; Zecchin, Sarah; Marzorati, Stefania; Goglio, Andrea; Cavalca, Lucia; Cristiani, Pierangela; Schievano, Andrea
2018-04-01
Recently, terracotta has attracted interest as low-cost and biocompatible material to build separators in microbial fuel cells (MFCs). However, the influence of a non-conductive material like terracotta on electroactive microbiological communities remains substantially unexplored. This study aims at describing the microbial pools developed from two different seed inocula (bovine and swine sewage) in terracotta-based air-breathing MFC. A statistical approach on microbiological data confirmed different community enrichment in the MFCs, depending mainly on the inoculum. Terracotta separators impeded the growth of electroactive communities in contact with cathodes (biocathodes), while a thick biofilm was observed on the surface (anolyte-side) of the terracotta separator. Terracotta-free MFCs, set as control experiments, showed a well-developed biocathode, Biocathode-MFCs resulted in 4 to 6-fold higher power densities. All biofilms were analyzed by high-throughput Illumina sequencing applied to 16S rRNA gene. The results showed more abundant (3- to 5-fold) electroactive genera (mainly Geobacter, Pseudomonas, Desulfuromonas and Clostridia MBA03) in terracotta-free biocathodes. Nevertheless, terracotta separators induced only slight changes in anodic microbial communities. Copyright © 2017 Elsevier B.V. All rights reserved.
Selvan, Ramakrishnan Kalai; Zhu, Pei; Yan, Chaoi; Zhu, Jiadeng; Dirican, Mahmut; Shanmugavani, A; Lee, Yun Sung; Zhang, Xiangwu
2018-03-01
Biomass-derived porous carbon has been considered as a promising sulfur host material for lithium-sulfur batteries because of its high conductive nature and large porosity. The present study explored biomass-derived porous carbon as polysulfide reservoir to modify the surface of glass fiber (GF) separator. Two different carbons were prepared from Oak Tree fruit shells by carbonization with and without KOH activation. The KOH activated porous carbon (AC) provides a much higher surface area (796 m 2 g -1 ) than pyrolized carbon (PC) (334 m 2 g -1 ). The R factor value, calculated from the X-ray diffraction pattern, revealed that the activated porous carbon contains more single-layer sheets with a lower degree of graphitization. Raman spectra also confirmed the presence of sp 3 -hybridized carbon in the activated carbon structure. The COH functional group was identified through X-ray photoelectron spectroscopy for the polysulfide capture. Simple and straightforward coating of biomass-derived porous carbon onto the GF separator led to an improved electrochemical performance in Li-S cells. The Li-S cell assembled with porous carbon modified GF separator (ACGF) demonstrated an initial capacity of 1324 mAh g -1 at 0.2 C, which was 875 mAh g -1 for uncoated GF separator (calculated based on the 2nd cycle). Charge transfer resistance (R ct ) values further confirmed the high ionic conductivity nature of porous carbon modified separators. Overall, the biomass-derived activated porous carbon can be considered as a promising alternative material for the polysulfide inhibition in Li-S batteries. Copyright © 2017 Elsevier Inc. All rights reserved.
Advanced flight hardware for organic separations using aqueous two-phase partitioning
NASA Astrophysics Data System (ADS)
Deuser, Mark S.; Vellinger, John C.; Weber, John T.
1996-03-01
Separation of cells and cell components is the limiting factor in many biomedical research and pharmaceutical development processes. Aqueous Two-Phase Partitioning (ATPP) is a unique separation technique which allows purification and classification of biological materials. SHOT has employed the ATPP process in separation equipment developed for both space and ground applications. Initial equipment development and research focused on the ORganic SEParation (ORSEP) space flight experiments that were performed on suborbital rockets and the shuttle. ADvanced SEParations (ADSEP) technology was developed as the next generation of ORSEP equipment through a NASA Small Business Innovation Research (SBIR) contract. Under the SBIR contract, a marketing study was conducted, indicating a growing commercial market exists among biotechnology firms for ADSEP equipment and associated flight research and development services. SHOT is preparing to begin manufacturing and marketing laboratory versions of the ADSEP hardware for the ground-based market. In addition, through a self-financed SBIR Phase III effort, SHOT is fabricating and integrating the ADSEP flight hardware for a commercially-driven SPACEHAB 04 experiment that will be the initial step in marketing space separations services. The ADSEP ground-based and microgravity research is expected to play a vital role in developing important new biomedical and pharmaceutical products.
New test techniques to evaluate near field effects for supersonic store carriage and separation
NASA Technical Reports Server (NTRS)
Sawyer, Wallace C.; Stallings, Robert L., Jr.; Wilcox, Floyd J., Jr.; Blair, A. B., Jr.; Monta, William J.; Plentovich, Elizabeth B.
1989-01-01
Store separation and store carriage drag studies were conducted. A primary purpose is to develop new experimental methods to evaluate near field effects of store separation and levels of store carriage drag associated with a variety of carriage techniques for different store shapes and arrangements. Flow field measurements consisting of surface pressure distributions and vapor screen photographs are used to analyze the variations of the store separation characteristics with cavity geometry. Store carriage drag measurements representative of tangent, semi-submerged, and internal carriage installations are presented and discussed. Results are included from both fully metric models and models with only metric segments (metric pallets) and the relative merits of the two are discussed. Carriage drag measurements for store installations on an aircraft parent body are compared both with prediction methods and with installations on a generic parent body.
Color separation in forensic image processing using interactive differential evolution.
Mushtaq, Harris; Rahnamayan, Shahryar; Siddiqi, Areeb
2015-01-01
Color separation is an image processing technique that has often been used in forensic applications to differentiate among variant colors and to remove unwanted image interference. This process can reveal important information such as covered text or fingerprints in forensic investigation procedures. However, several limitations prevent users from selecting the appropriate parameters pertaining to the desired and undesired colors. This study proposes the hybridization of an interactive differential evolution (IDE) and a color separation technique that no longer requires users to guess required control parameters. The IDE algorithm optimizes these parameters in an interactive manner by utilizing human visual judgment to uncover desired objects. A comprehensive experimental verification has been conducted on various sample test images, including heavily obscured texts, texts with subtle color variations, and fingerprint smudges. The advantage of IDE is apparent as it effectively optimizes the color separation parameters at a level indiscernible to the naked eyes. © 2014 American Academy of Forensic Sciences.
Space Station Water Processor Mostly Liquid Separator (MLS)
NASA Technical Reports Server (NTRS)
Lanzarone, Anthony
1995-01-01
This report presents the results of the development testing conducted under this contract to the Space Station Water Processor (WP) Mostly Liquid Separator (MLS). The MLS units built and modified during this testing demonstrated acceptable air/water separation results in a variety of water conditions with inlet flow rates ranging from 60 - 960 LB/hr.
Low-cost Radon Reduction Pilot Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rose, William B.; Francisco, Paul W.; Merrin, Zachary
The U.S. Department of Energy's Building America research team Partnership for Advanced Residential Retrofits conducted a primary scoping study on the impact of air sealing between the foundation and the living space on radon transport reduction across the foundation and living space floor assembly. Fifteen homes in the Champaign, Illinois, area participated in the study. These homes were instrumented for hourly continuous radon measurements and simultaneous temperature and humidity measurements. Blower door and zone pressure diagnostics were conducted at each house. The treatments consisted of using air-sealing foams at the underside of the floor that separated the living space frommore » the foundation and providing duct sealing on the ductwork that is situated in the foundation area. The hypothesis was that air sealing the floor system that separated the foundation from the living space should better isolate the living space from the foundation; this isolation should lead to less radon entering the living space from the foundation. If the hypothesis had been proven, retrofit energy-efficiency programs may have chosen to adopt these isolation methods for enhanced radon protection to the living space.« less
Rubio-Aparicio, María; Sánchez-Meca, Julio; López-López, José Antonio; Botella, Juan; Marín-Martínez, Fulgencio
2017-11-01
Subgroup analyses allow us to examine the influence of a categorical moderator on the effect size in meta-analysis. We conducted a simulation study using a dichotomous moderator, and compared the impact of pooled versus separate estimates of the residual between-studies variance on the statistical performance of the Q B (P) and Q B (S) tests for subgroup analyses assuming a mixed-effects model. Our results suggested that similar performance can be expected as long as there are at least 20 studies and these are approximately balanced across categories. Conversely, when subgroups were unbalanced, the practical consequences of having heterogeneous residual between-studies variances were more evident, with both tests leading to the wrong statistical conclusion more often than in the conditions with balanced subgroups. A pooled estimate should be preferred for most scenarios, unless the residual between-studies variances are clearly different and there are enough studies in each category to obtain precise separate estimates. © 2017 The British Psychological Society.
Kim, Ilhwan; Kim, Bong Sung; Nam, Seunghoon; Lee, Hoo-Jeong; Chung, Ho Kyoon; Cho, Sung Min; Luu, Thi Hoai Thuong; Hyun, Seungmin; Kang, Chiwon
2018-01-01
Here, we fabricate poly(vinylidene fluoride-co-hexafluoropropene) (PVDF-co-HFP) by electrospinning for a gel polymer electrolyte (GPE) for use in flexible Li-ion batteries (LIBs). As a solvent, we use N-methyl-2-pyrrolidone (NMP), which helps produce the cross-linked morphology of PVDF-co-HFP separator, owing to its low volatility. The cross-linked PVDF-co-HFP separator shows an uptake rate higher than that of a commercialized polypropylene (PP) separator. Moreover, the PVDF-co-HFP separator shows an ionic conductivity of 2.3 × 10−3 S/cm at room temperature, comparable with previously reported values. An LIB full-cell assembled with the PVDF-co-HFP-based GPE shows capacities higher than its counterpart with the commercialized PP separator, confirming that the cross-linked PVDF-co-HFP separator provides highly efficient ionic conducting pathways. In addition, we integrate a flexible LIB cell using the PVDF-co-HFP GPE with a flexible organic light emitting diode (OLED), demonstrating a fully flexible unit of LIB and OLED. PMID:29614800
Kim, Ilhwan; Kim, Bong Sung; Nam, Seunghoon; Lee, Hoo-Jeong; Chung, Ho Kyoon; Cho, Sung Min; Luu, Thi Hoai Thuong; Hyun, Seungmin; Kang, Chiwon
2018-04-02
Here, we fabricate poly(vinylidene fluoride- co -hexafluoropropene) (PVDF- co -HFP) by electrospinning for a gel polymer electrolyte (GPE) for use in flexible Li-ion batteries (LIBs). As a solvent, we use N -methyl-2-pyrrolidone (NMP), which helps produce the cross-linked morphology of PVDF- co -HFP separator, owing to its low volatility. The cross-linked PVDF- co -HFP separator shows an uptake rate higher than that of a commercialized polypropylene (PP) separator. Moreover, the PVDF- co -HFP separator shows an ionic conductivity of 2.3 × 10 -3 S/cm at room temperature, comparable with previously reported values. An LIB full-cell assembled with the PVDF- co -HFP-based GPE shows capacities higher than its counterpart with the commercialized PP separator, confirming that the cross-linked PVDF- co -HFP separator provides highly efficient ionic conducting pathways. In addition, we integrate a flexible LIB cell using the PVDF- co -HFP GPE with a flexible organic light emitting diode (OLED), demonstrating a fully flexible unit of LIB and OLED.
Novel microfluidic device for the continuous separation of cancer cells using dielectrophoresis.
Alazzam, Anas; Mathew, Bobby; Alhammadi, Falah
2017-03-01
We describe the design, microfabrication, and testing of a microfluidic device for the separation of cancer cells based on dielectrophoresis. Cancer cells, specifically green fluorescent protein-labeled MDA-MB-231, are successfully separated from a heterogeneous mixture of the same and normal blood cells. MDA-MB-231 cancer cells are separated with an accuracy that enables precise detection and counting of circulating tumor cells present among normal blood cells. The separation is performed using a set of planar interdigitated transducer electrodes that are deposited on the surface of a glass wafer and slightly protrude into the separation microchannel at one side. The device includes two parts, namely, a glass wafer and polydimethylsiloxane element. The device is fabricated using standard microfabrication techniques. All experiments are conducted with low conductivity sucrose-dextrose isotonic medium. The variation in response between MDA-MB-231 cancer cells and normal cells to a certain band of alternating-current frequencies is used for continuous separation of cells. The fabrication of the microfluidic device, preparation of cells and medium, and flow conditions are detailed. The proposed microdevice can be used to detect and separate malignant cells from heterogeneous mixture of cells for the purpose of early screening for cancer. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Shao, Hongyuan; Wang, Weikun; Zhang, Hao; Wang, Anbang; Chen, Xiaonong; Huang, Yaqin
2018-02-01
Despite recent progress in designing modified separators for lithium-sulfur (Li-S) batteries, detail in optimizing the synergistic effect between chemical and physical immobilization for lithium polysulfides (LiPS) in modified separator hasn't been investigated totally. Here, a nano-TiO2 decorated carbon layer (T-DCL) has been successfully applied to modify separator for the Li-S battery. The results indicate that appropriate weight percentage of nano-TiO2 uniformly distributed in conductive carbon layer is effective to chemically and physically immobilize for LiPS, and promote the electron transfer during discharge/charge process. The performance of the modified Li-S battery with T-DCL separator are significantly enhanced, with a specific capacity of 883 mAh g-1 retained after 180 cycles at 0.1 C and 762 mAh g-1 retained after 200 cycles at 0.5C, which are much higher than that of separators only coated with TiO2 layer or conductive carbon layer. Besides, the separator coated with T-DCL also shows low electrochemical impedance and good lithium anode protection. These results indicate that separator with T-DCL is promising to balance the physical and chemical LiPS trapping effect, and optimize the electrochemical performance for Li-S battery.
Polymeric membrane systems of potential use for battery separators
NASA Technical Reports Server (NTRS)
Philipp, W. H.
1977-01-01
Two membrane systems were investigated that may have potential use as alkaline battery separators. One system comprises two miscible polymers: a support polymer (e.g., polyvinyl formal) and an ion conductor such as polyacrylic acid. The other system involves a film composed of two immiscible polymers: a conducting polymer (e.g., calcium polyacrylate) suspended in an inert polymer support matrix, polyphenylene oxide. Resistivities in 45-percent potassium hydroxide and qualitative mechanical properties are presented for films comprising various proportions of conducting and support polymers. In terms of these parameters, the results are encouraging for optimum ratios of conducting to support polymers.
Molecular dynamics studies of interpenetrating polymer networks for actuator devices
NASA Astrophysics Data System (ADS)
Brandell, Daniel; Kasemägi, Heiki; Citérin, Johann; Vidal, Frédéric; Chevrot, Claude; Aabloo, Alvo
2008-03-01
Molecular Dynamics (MD) techniques have been used to study the structure and dynamics of a model system of an interpenetrating polymer (IPN) network for actuator devices. The systems simulated were generated using a Monte Carlo-approach, and consisted of poly(ethylene oxide) (PEO) and poly(butadiene) (PB) in a 80-20 percent weight ratio immersed into propylene carbonate (PC) solutions of LiClO 4. The total polymer content was 32%, in order to model experimental conditions. The dependence of LiClO 4 concentration in PC has been studied by studying five different concentrations: 0.25, 0.5, 0.75, 1.0 and 1.25 M. After equilibration, local structural properties and dynamical features such as phase separation, coordination, cluster stability and ion conductivity were studied. In an effort to study the conduction processes more carefully, external electric fields of 1×10 6 V/m and 5×10 6 V/m has been applied to the simulation boxes. A clear relationship between the degree of local phase separation and ion mobility is established. It is also shown that although the ion pairing increases with concentration, there are still significantly more potential charge carriers in the higher concentrated systems, while concentrations around 0.5-0.75 M of LiClO 4 in PC seem to be favorable in terms of ion mobility. Furthermore, the anions exhibit higher conductivity than the cations, and there are tendencies to solvent drag from the PC molecules.
Homophobic and Transphobic Bullying: Barriers and Supports to School Intervention
ERIC Educational Resources Information Center
O'Donoghue, Kate; Guerin, Suzanne
2017-01-01
This study explores the perceived barriers and supports identified by school staff in tackling homophobic and transphobic bullying, using Bronfenbrenner's ecological model as a framework. Semi-structured interviews were conducted with participants from five separate second-level/high schools (two designated disadvantaged schools, and three…
Validity of Sex-Balanced Interest Inventory Scales
ERIC Educational Resources Information Center
Hanson, Gary R.; Rayman, Jack
1976-01-01
This study examines the effectiveness of sex-balanced and sex-restrictive raw score interest scales in discriminating among vocational preference groups. Analyses were conducted separately for 502 males in six vocational preference groups and 878 females in five vocational preference groups. Differences may restrict career suggestions provided to…
Effect of moisture content on the coefficient of thermal expansion of concrete.
DOT National Transportation Integrated Search
2007-09-01
The purpose of this report is to discuss a study conducted on twenty separate mix designs of concrete and the effects of : the aggregate type, moisture content, and temperature on the coefficient of thermal expansion(CTE). These results are to be use...
In the Pacific Northwest Zostera marina and Z. japonica co-exist by occupying separate elevation niches. We conducted two mesocosm experiments to evaluate light and temperature as factors controlling the disjunct distribution of congeners. The first study tests the hypothesis t...
Increasing Institutional Effectiveness: A Continuous Effort after Accreditation.
ERIC Educational Resources Information Center
Chen, HongYu
West Virginia University at Parkersburg (WVUP) is a separately accredited campus of the University offering 2 baccalaureate, 10 associate, and 2 certificate programs. In response to concerns raised in a recent accreditation report, WVUP conducted a study examining student attitudes toward facilities, course scheduling, student advising,…
Aeroheating Characteristics for a Two-Stage-To-Orbit Concept During Separation at Mach 6
NASA Technical Reports Server (NTRS)
Liechty, Derek S.
2005-01-01
An experimental study was conducted to determine the proximity aeroheating characteristics for a two-stage-to-orbit concept in close proximity in the NASA Langley 20-Inch Mach 6 Air Tunnel. A new hybrid discrete thin-film resistance gauge technique was evaluated in this study and used to measure experimental interference heating levels between the booster and the orbiter at a constant freestream Reynolds number of 8.25 x 10(exp 6)/m and a variety of separation and axial offset distances. It was found that, as the orbiter separates from the booster and the booster falls away, the windward centerline heating increased on the orbiter by as much as 13-times over the baseline, single model heating distribution, and on the booster by as much as 6-times. The aeroheating database developed can be used for computational fluid dynamic code validation.
Microfabricated Genomic Analysis System
NASA Technical Reports Server (NTRS)
Gonda, Steve; Elms, Rene
2005-01-01
Genetic sequencing and many genetic tests and assays require electrophoretic separation of DNA. In this technique, DNA fragments are separated by size as they migrate through a sieving gel under the influence of an applied electric field. In order to conduct these analyses on-orbit, it is essential to acquire the capability to efficiently perform electrophoresis in a microgravity environment. Conventional bench top electrophoresis equipment is large and cumbersome and does not lead itself to on-orbit utilization. Much of the previous research regarding on-orbit electrophoresis involved altering conventional electrophoresis equipment for bioprocessing, purification, and/or separation technology applications. A new and more efficient approach to on-orbit electrophoresis is the use of a microfabricated electrophoresis platform. These platforms are much smaller, less expensive to produce and operate, use less power, require smaller sample sizes (nanoliters), and achieve separation in a much shorter distance (a few centimeters instead of 10 s or 100 s of centimeters.) In contrast to previous applications, this platform would be utilized as an analytical tool for life science/medical research, environmental monitoring, and medical diagnoses. Identification of infectious agents as well as radiation related damage are significant to NASA s efforts to maintain, study, and monitor crew health during and in support of near-Earth and interplanetary missions. The capability to perform genetic assays on-orbit is imperative to conduct relevant and insightful biological and medical research, as well as continuing NASA s search for life elsewhere. This technology would provide an essential analytical tool for research conducted in a microgravity environment (Shuttle, ISS, long duration/interplanetary missions.) In addition, this technology could serve as a critical and invaluable component of a biosentinel system to monitor space environment genotoxic insults to include radiation.
NASA Technical Reports Server (NTRS)
Campbell, J. H., II
1975-01-01
Experimental aerodynamic investigations were conducted from July 5 through July 17, 1973, on a 0.01 scale model. The AEDC captive trajectory system was utilized in conjunction with the tunnel primary sector to obtain grid-type data for external tank abort from the orbiter, and for nominal separation of one solid rocket booster from the orbiter-tank combination. Booster separation was investigated with and without separation motors plume simulation. The plumes were generated by eight M sub j = 2.15 nozzles using a 1500 psia cold air supply. Free stream data were obtained for all models (orbiter, tank, orbiter-tank, and right-hand booster) to provide baselines for evaluation of proximity effects.
Process for analyzing CO.sub.2 in seawater
Atwater, James E.; Akse, James R.; DeHart, Jeffrey
1997-01-01
The process of this invention comprises providing a membrane for separating CO.sub.2 into a first CO.sub.2 sample phase and a second CO.sub.2 analyte phase. CO.sub.2 is then transported through the membrane thereby separating the CO.sub.2 with the membrane into a first CO.sub.2 sample phase and a second CO.sub.2 analyte liquid phase including an ionized, conductive, dissociated CO.sub.2 species. Next, the concentration of the ionized, conductive, dissociated CO.sub.2 species in the second CO.sub.2 analyte liquid phase is chemically amplified using a water-soluble chemical reagent which reversibly reacts with undissociated CO.sub.2 to produce conductivity changes therein corresponding to fluctuations in the partial pressure of CO.sub.2 in the first CO.sub.2 sample phase. Finally, the chemically amplified, ionized, conductive, dissociated CO.sub.2 species is introduced to a conductivity measuring instrument. Conductivity changes in the chemically amplified, ionized, conductive, dissociated CO.sub.2 species are detected using the conductivity measuring instrument.
Yusko, Brittany; Hawk, Kiel; Schiml, Patricia A.; Deak, Terrence; Hennessy, Michael B.
2011-01-01
Infant guinea pigs exhibit a 2-stage response to maternal separation: an initial active stage, characterized by vocalizing, and a second passive stage marked by depressive-like behavior (hunched posture, prolonged eye-closure, extensive piloerection) that appears to be mediated by proinflammatory activity. Recently we found that pups showed an enhanced (i.e., sensitized) depressive-like behavioral response during repeated separation. Further, core body temperature was higher during the beginning of a second separation compared to the first, suggesting a more-rapid stress-induced febrile response to separation the second day, though the possibility that temperature was already elevated prior to the second separation could not be ruled out. Therefore, the present study examined temperature prior to, and during, 2 daily separations. We also examined the temperature response to a third separation conducted 3 days after the second, and assessed the effect of repeated separation on plasma cortisol levels. Core temperature did not differ just prior to the separations, but showed a more-rapid increase and then decline during both a second and third separation than during a first. Temperature responses were not associated with changes in motor activity. Depressive-like behavior was greater during the second and third separations. Pups separated a first time showed a larger plasma cortisol response at the conclusion of separation than did animals of the same age separated a third time. In all, the results indicate that the sensitization of depressive-like behavior during repeated separations over several days is accompanied by a more-rapid febrile response that may be related to a reduction of glucocorticoid suppression. PMID:22079581
ERIC Educational Resources Information Center
McEwan, Barbara; Gathercoal, Paul; Nimmo, Virginia
This paper presents a composite of four separate research studies conducted to assess the impact of constitutional language on classroom environments. The studies were designed to examine the uses of "Judicious Discipline" in a variety of classrooms and how the use of a common language based on rights and responsibilities affected the…
ERIC Educational Resources Information Center
Sturge-Apple, Melissa L.; Rogge, Ronald D.; Skibo, Michael A.; Peltz, Jack S.; Suor, Jennifer H.
2015-01-01
Extending dual process frameworks of cognition to a novel domain, the present study examined how mothers' explicit and implicit attitudes about her child may operate in models of parenting. To assess implicit attitudes, two separate studies were conducted using the same child-focused Go/No-go Association Task (GNAT-Child). In Study 1, model…
The Long-Term Outcome of Children by Birth Weight and Gestational Age. High-Risk Follow-Up Study.
ERIC Educational Resources Information Center
Colorado Univ., Denver. Medical Center.
This report is comprised of three separate studies conducted at the University of Colorado Medical Center. In the first study, answers to the following questions were sought: (1) What kinds of late morbidity occur at different birth weights and gestational ages? and (2) Has a vigorous approach to metabolic support in the newborn period changed the…
Method and apparatus for continuous electrophoresis
Watson, Jack S.
1992-01-01
A method and apparatus for conducting continuous separation of substances by electrophoresis are disclosed. The process involves electrophoretic separation combined with couette flow in a thin volume defined by opposing surfaces. By alternating the polarity of the applied potential and producing reciprocating short rotations of at least one of the surfaces relative to the other, small increments of separation accumulate to cause substantial, useful segregation of electrophoretically separable components in a continuous flow system.
Low-bias negative differential conductance controlled by electrode separation
NASA Astrophysics Data System (ADS)
Yi, Xiao-Hua; Liu, Ran; Bi, Jun-Jie; Jiao, Yang; Wang, Chuan-Kui; Li, Zong-Liang
2016-12-01
The electronic transport properties of a single thiolated arylethynylene molecule with 9,10-dihydroanthracene core, denoted as TADHA, is studied by using non-equilibrium Green’s function formalism combined with ab initio calculations. The numerical results show that the TADHA molecule exhibits excellent negative differential conductance (NDC) behavior at lower bias regime as probed experimentally. The NDC behavior of TADHA molecule originates from the Stark effect of the applied bias voltage, by which the highest occupied molecular orbital (HOMO) and the HOMO-1 are pulled apart and become localized. The NDC behavior of TADHA molecular system is tunable by changing the electrode distance. Shortening the electrode separation can enhance the NDC effect which is attributed to the possible increase of coupling between the two branches of TADHA molecule. Project supported by the National Natural Science Foundation of China (Grant Nos. 11374195 and 11405098) and the Natural Science Foundation of Shandong Province, China (Grant No. ZR2013FM006).
A Comparison of Leadership Styles and Organizational Cultures.
ERIC Educational Resources Information Center
Ortiz, Flora Ida
Three separate studies of three different school superintendents are reported on in terms of the effect of leadership styles on organizational cultures. The analysis used nine descriptors derived from Schein's comprehensive description of leadership in the conduct of organizational culture creation. The report is based on historical and…
Stimulus Fading and Transfer in the Treatment of Self-Restraint and Self-Injurious Behavior.
ERIC Educational Resources Information Center
Pace, Gary M.; And Others
1986-01-01
Manipulation of mechanical restraint properties were conducted in separate studies with two profoundly retarded adolescents who exhibited both self-restraint and self-injurious behavior. Techniques included prompting, differential reinforcement, and stimulus fading. Results suggested that stimulus fading and transfer may be valuable components in…
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...
Physiological responses of planting frozen and thawed Douglas-fir seedlings
M. Anisul Islam; Kent G. Apostol; Douglass F. Jacobs; R. Kasten Dumroese
2008-01-01
We studied the short-term (7-day) physiological responses of planting thawed and frozen root plugs of Douglas-fir (Pseudotsuga menziesii) seedlings in 2 separate experiments under cool-moist and warm-dry growing conditions, respectively. Our results showed that shoot water potential, root hydraulic conductance, net photosynthesis (A), and...
Community Needs Assessment Survey Report, Fall 1990.
ERIC Educational Resources Information Center
Gainesville Coll., GA. Office of Planning and Institutional Research.
As part of the Southern Association of Colleges and Schools self-study process for reaffirmation of accreditation, Gainesville College (GC) conducted its second decennial needs assessment survey in fall 1990 to obtain data to assist in college planning and program improvement. Separate survey instruments were developed to gather data from…
Pushing Boundaries: Language and Culture in a Mexicano Community.
ERIC Educational Resources Information Center
Vasquez, Olga A.; Pease-Alvarez, Lucinda; Shannon, Sheila M.
This book describes how bilingual children and their families actively and innovatively use available cultural and linguistic resources to pursue their goals. Three separate ethnographic studies were conducted within the same Mexicano community in Lincoln City, California. Descriptions of everyday talk of children and adults focus on how children…
To conduct the health-effect studies described in subsequent articles, concentrated aqueous mixtures of disinfection byproducts were required for the two separate treatment trains described in the preceding article. To accomplish this, the finished drinking waters from each trea...
British Register of Reading Research. No. 2.
ERIC Educational Resources Information Center
Goodacre, Elizabeth J., Comp.; Bentley, Diana, Comp.
Separate listings of both ongoing and completed reading research in Great Britain between 1974 and 1977--including relevant language studies and research on spelling--are arranged alphabetically by researcher, reporting the research title, the institution at which the research was conducted, the years started and completed, and the type of…
Module for phosphorus separation and recycling from liquid manures
USDA-ARS?s Scientific Manuscript database
A method has been developed to extract and concentrate soluble phosphates from livestock wastewater. The research was conducted over a 10-year period and went from initial bench studies and discovery, to pilot module development, to full-scale demonstrations of the phosphorus (P) module in swine fa...
Comprehensive field studies were conducted to evaluate the performance of sampling methods for measuring the coarse fraction of PM10 in ambient air. Five separate sampling approaches were evaluated at each of three sampling sites. As the primary basis of comparison, a discret...
Comprehensive field studies were conducted to evaluate the performance of sampling methods for measuring the coarse fraction of PM10 in ambient air. Five separate sampling approaches were evaluated at each of three sampling sites. As the primary basis of comparison, a discret...
Comprehensive field studies were conducted to evaluate the performance of sampling methods for measuring the coarse fraction of PM10 in ambient air. Five separate sampling approaches were evaluated at each of three sampling sites. As the primary basis of comparison, a discrete ...
Film: Interdisciplinary Approaches to Theory and Teaching. Part One.
ERIC Educational Resources Information Center
Gottesman, Ronald, Ed.; Benamou, Michel, Ed.
1976-01-01
This journal offers a selection from papers presented at two scholarly meetings on research on film conducted at the Center for Twentieth Century Studies. Separate papers deal with the following topics: film and ideology; the filmic apparatus; the inadequacies of current conceptions of film historiography; nonlinguistic extensions of film and…
DOT National Transportation Integrated Search
2002-06-01
Two separate studies were accomplished to investigate human factors issues related to the use of lap belts. Human performance trials were conducted under two protocols to measure and assess: (1) seat belt tension adjustment during normal flight and e...
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.
Verification testing of the Brome Agri Sales Ltd. Maximizer Separator, Model MAX 1016 (Maximizer) was conducted at the Lake Wheeler Road Field Laboratory Swine Educational Unit in Raleigh, North Carolina. The Maximizer is an inclined screen solids separator that can be used to s...
Verification testing of the BaySaver Separation System, Model 10K was conducted on a 10 acre drainage basin near downtown Griffin, Georgia. The system consists of two water tight pre-cast concrete manholes and a high-density polyethylene BaySaver Separator Unit. The BaySaver Mod...
Energy efficient engine: Preliminary design and integration studies
NASA Technical Reports Server (NTRS)
Johnston, R. P.; Hirschkron, R.; Koch, C. C.; Neitzel, R. E.; Vinson, P. W.
1978-01-01
Parametric design and mission evaluations of advanced turbofan configurations were conducted for future transport aircraft application. Economics, environmental suitability and fuel efficiency were investigated and compared with goals set by NASA. Of the candidate engines which included mixed- and separate-flow, direct-drive and geared configurations, an advanced mixed-flow direct-drive configuration was selected for further design and evaluation. All goals were judged to have been met except the acoustic goal. Also conducted was a performance risk analysis and a preliminary aerodynamic design of the 10 stage 23:1 pressure ratio compressor used in the study engines.
Particle size reduction of propellants by cryocycling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Whinnery, L.; Griffiths, S.; Lipkin, J.
1995-05-01
Repeated exposure of a propellant to liquid nitrogen causes thermal stress gradients within the material resulting in cracking and particle size reduction. This process is termed cryocycling. The authors conducted a feasibility study, combining experiments on both inert and live propellants with three modeling approaches. These models provided optimized cycle times, predicted ultimate particle size, and allowed crack behavior to be explored. Process safety evaluations conducted separately indicated that cryocycling does not increase the sensitivity of the propellants examined. The results of this study suggest that cryocycling is a promising technology for the demilitarization of tactical rocket motors.
Yaghi, Omar M.; Wan, Shun; Doonan, Christian J.; Wang, Bo; Deng, Hexiang
2016-02-23
The disclosure relates generally to materials that comprise conductive covalent organic frameworks. The disclosure also relates to materials that are useful to store and separate gas molecules and sensors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yaghi, Omar M.; Wan, Shun; Doonan, Christian J.
The disclosure relates generally to materials that comprise conductive covalent organic frameworks. The disclosure also relates to materials that are useful to store and separate gas molecules and sensors.
Preparation of Proton Exchange Membranes and Lithium Batteries from Melamine-containing Ormosils
NASA Technical Reports Server (NTRS)
Tigelaar, Dean M.; Kinder, James D.; Meador, Mary Ann; Waldecker, James; Bennett, William R.
2004-01-01
Our laboratory has recently reported a series of rodcoil polymers for lithium batteries that display dimensionally stable films with good ionic conductivity. The rod segments consist of rigid linear and branched polyimides and the coil segments are polyethylene oxides (PEO). It has been proposed that good mechanical and transport properties are due to phase separation between the rod and coil segments. It was also observed that increased branching and molecular weight lead to increased conductivity. The following study was undertaken to assess the effects of phase separation in polyalkylene oxides connected by melamine linkages. Melamine was chosen as the linking unit because it provides a branching site, cation binding sites to help ionic transport between polymer chains, and the opportunity for self assembly through hydrogen bonding. Polymers were made by the reaction of cyanuric chloride with a series of amine-terminated alkylene oxides. A linear polymer was first made, followed by reaction of the third site on cyanuric chloride with varying ratios of monofunctional Jeffamine and (3-aminopropyl)triethoxysilane. The lithium trifluoromethane sulfonamide-doped polymers are then crosslinked through a sol-gel process to form free-standing films. Initial results have shown mechanically strong films with lithium conductivities on the order of 2 x 10(exp -5) S/cm at ambient temperature. In a separate study, organically modified silanes (Ormosils) that contain sulfonic acid derivatized melamines have been incorporated into proton exchange membranes. The membranes are made by reaction of the primary amine groups of various ratios of melamine derivative and difunctional Jeffamine (MW = 2000) with the epoxide group of (3-Glycidyloxypropyl)trimethoxysilane. The films were then cross-linked through a sol-gel process. Resulting sulfuric acid doped films are strong, flexible, and have proton conductivities on the order of 2 x l0(exp -2) S/cm (120 C, 25% relative humidity). Our best results have been observed when films contain 60% PEO and 40% sulfonated melamine.
Regaining Lost Separation in a Piloted Simulation of Autonomous Aircraft Operations
NASA Technical Reports Server (NTRS)
Barhydt, Richard; Eischeid, Todd M.; Palmer, Michael T.; Wing, David J.
2002-01-01
NASA is currently investigating a new concept of operations for the National Airspace System, designed to improve capacity while maintaining or improving current levels of safety. This concept, known as Distributed Air/Ground Traffic Management (DAG-TM), allows appropriately equipped autonomous aircraft to maneuver freely for flight optimization while resolving conflicts with other traffic and staying out of special use airspace and hazardous weather. While Airborne Separation Assurance System (ASAS) tools would normally allow pilots to resolve conflicts before they become hazardous, evaluation of system performance in sudden, near-term conflicts is needed in order to determine concept feasibility. If an acceptable safety level can be demonstrated in these situations, then operations may be conducted with lower separation minimums. An experiment was conducted in NASA Langley s Air Traffic Operations Lab to address issues associated with resolving near-term conflicts and the potential use of lower separation minimums. Sixteen commercial airline pilots flew a total of 32 traffic scenarios that required them to use prototype ASAS tools to resolve close range pop-up conflicts. Required separation standards were set at either 3 or 5 NM lateral spacing, with 1000 ft vertical separation being used for both cases. Reducing the lateral separation from 5 to 3 NM did not appear to increase operational risk, as indicated by the proximity to the intruder aircraft. Pilots performed better when they followed tactical guidance cues provided by ASAS than when they didn't follow the guidance. As air-air separation concepts are evolved, further studies will consider integration issues between ASAS and existing Airborne Collision Avoidance Systems (ACAS).These types of non-normal events will require the ASAS to provide effective alerts and resolutions prior to the time that an Airborne Collision Avoidance System (ACAS) would give a Resolution Advisory (RA). When an RA is issued, a pilot must take immediate action in order to avoid a potential near miss. The Traffic Alert and Collision Avoidance System (TCAS) II currently functions as an ACAS aboard commercial aircraft. Depending on the own aircraft s altitude, TCAS only issues RA s 15-35 seconds prior to the Closest Point of Approach (CPA). Prior to an RA, DAG-TM pilots operating autonomous aircraft must rely solely on ASAS for resolution guidance. An additional area of DAG-TM concept feasibility relates to a potential reduction in separation standards. Lower separation standards are likely needed in order to improve NAS efficiency and capacity. Current separation minimums are based in large part on the capabilities of older radar systems. Safety assessments are needed to determine the feasibility of reduced separation minimums. They will give strong consideration to surveillance system performance, including accuracy, integrity, and availability. Candidate surveillance systems include Automatic Dependent Surveillance-Broadcast (ADS-B) and multi-lateration systems. Considering studies done for Reduced Vertical Separation Minimums (RVSM) operations, it is likely that flight technical errors will also be considered. In addition to a thorough evaluation of surveillance system performance, a potential decision to lower the separation standards should also take operational considerations into account. An ASAS Safety Assessment study identified improper maneuvering in response to a conflict (due to ambiguous or improper resolution commands or a pilot s failure to comply with the resolution) as a potential safety risk. If near-term conflicts with lower separation minimums were determined to be more challenging for pilots, the severity of these risks could be even greater.
A Passive Cavity Concept for Improving the Off-Design Performance of Fixed-Geometry Exhaust Nozzles
NASA Technical Reports Server (NTRS)
Asbury, Scott C.; Gunther, Christopher L.; Hunter, Craig A.
1996-01-01
An investigation was conducted in the model preparation area of the Langley 16-Foot Transonic Tunnel to study a passive cavity concept for improving the off-design performance of fixed-geometry exhaust nozzles. Passive cavity ventilation (through a porous surface) was applied to divergent flap surfaces and tested at static conditions in a sub-scale, nonaxisymmetric, convergent-divergent nozzle. As part of a comprehensive investigation, force, moment and pressure measurements were taken and focusing schlieren flow visualization was obtained for a baseline configuration and D passive cavity configurations. All tests were conducted with no external flow and high-pressure air was used to simulate jet-exhaust flow at nozzle pressure ratios from 1.25 to approximately 9.50. Results indicate that baseline nozzle performance was dominated by unstable shock-induced boundary-layer separation at off-design conditions, which came about through the natural tendency of overexpanded exhaust flow to satisfy conservation requirements by detaching from the nozzle divergent flaps. Passive cavity ventilation added the ability to control off-design separation in the nozzle by either alleviating separation or encouraging stable separation of the exhaust flow. Separation alleviation offers potential for installed nozzle performance benefits by reducing drag at forward flight speeds, even though it may reduce off-design static thrust efficiency as much as 3.2 percent. Encouraging stable separation of the exhaust flow offers significant performance improvements at static, low NPR and low Mach number flight conditions by improving off-design static thrust efficiency as much as 2.8 percent. By designing a fixed-geometry nozzle with fully porous divergent flaps, where both cavity location and percent open porosity of the flaps could be varied, passive flow control would make it possible to improve off-design nozzle performance across a wide operating range. In addition, the ability to encourage separation on one flap while alleviating it on the other makes it possible to generate thrust vectoring in the nozzle through passive flow control.
Shadpour, Hamed; Hupert, Mateusz L; Patterson, Donald; Liu, Changgeng; Galloway, Michelle; Stryjewski, Wieslaw; Goettert, Jost; Soper, Steven A
2007-02-01
A 16-channel microfluidic chip with an integrated contact conductivity sensor array is presented. The microfluidic network consisted of 16 separation channels that were hot-embossed into polycarbonate (PC) using a high-precision micromilled metal master. All channels were 40 microm deep and 60 microm wide with an effective separation length of 40 mm. A gold (Au) sensor array was lithographically patterned onto a PC cover plate and assembled to the fluidic chip via thermal bonding in such a way that a pair of Au microelectrodes (60 microm wide with a 5 microm spacing) was incorporated into each of the 16 channels and served as independent contact conductivity detectors. The spacing between the corresponding fluidic reservoirs for each separation channel was set to 9 mm, which allowed for loading samples and buffers to all 40 reservoirs situated on the microchip in only five pipetting steps using an 8-channel pipettor. A printed circuit board (PCB) with platinum (Pt) wires was used to distribute the electrophoresis high-voltage to all reservoirs situated on the fluidic chip. Another PCB was used for collecting the conductivity signals from the patterned Au microelectrodes. The device performance was evaluated using microchip capillary zone electrophoresis (mu-CZE) of amino acid, peptide, and protein mixtures as well as oligonucleotides that were separated via microchip capillary electrochromatography (mu-CEC). The separations were performed with an electric field (E) of 90 V/cm and were completed in less than 4 min in all cases. The conductivity detection was carried out using a bipolar pulse voltage waveform with a pulse amplitude of +/-0.6 V and a frequency of 6.0 kHz. The conductivity sensor array concentration limit of detection (SNR = 3) was determined to be 7.1 microM for alanine. The separation efficiency was found to be 6.4 x 10(4), 2.0 x 10(3), 4.8 x 10(3), and 3.4 x 10(2) plates for the mu-CEC of the oligonucleotides and mu-CZE of the amino acids, peptides, and proteins, respectively, with an average channel-to-channel migration time reproducibility of 2.8%. The average resolution obtained for mu-CEC of the oligonucleotides and mu-CZE of the amino acids, peptides, and proteins was 4.6, 1.0, 0.9, and 1.0, respectively. To the best of our knowledge, this report is the first to describe a multichannel microchip electrophoresis device with integrated contact conductivity sensor array.
ERIC Educational Resources Information Center
Freisthler, Bridget; Gruenewald, Paul J.; Johnson, Fred W.; Treno, Andrew J.; Lascala, Elizabeth A.
2005-01-01
This study examines the spatial relationship between drug availability and rates of drug use in neighborhood areas. Responses from 16,083 individuals were analyzed at the zip code level (n = 158) and analyses were conducted separately for youth and adults using spatial regression techniques. The dependent variable is the percentage of respondents…
ERIC Educational Resources Information Center
Virginia Adult Educators Research Network, Dayton.
This report contains four separate articles of interest to adult English-as-a-second-language (ESL) educators. "Learning Disabilities in Adult ESL: Case Studies and Directions" (Dorothy Almanza, Kate Singleton, Lynda Terrill) looks at three case studies of adult ESL students whom teachers have identified as possibly learning disabled.…
Economic Consequences of Marital Disruption for Women in Their Middle Years.
ERIC Educational Resources Information Center
Shaw, Lois B.
An analysis of data from the National Longitudinal Study (NLS) was conducted to determine whether marital disruption (by death, divorce, or separation) caused poverty in the early years after a marriage ends and whether the poverty was long-term or short-term. The study examined data on women who had experienced a disruption before 1967 and were…
Sudell, Maria; Tudur Smith, Catrin; Gueyffier, François; Kolamunnage-Dona, Ruwanthi
2018-04-15
Joint modelling of longitudinal and time-to-event data is often preferred over separate longitudinal or time-to-event analyses as it can account for study dropout, error in longitudinally measured covariates, and correlation between longitudinal and time-to-event outcomes. The joint modelling literature focuses mainly on the analysis of single studies with no methods currently available for the meta-analysis of joint model estimates from multiple studies. We propose a 2-stage method for meta-analysis of joint model estimates. These methods are applied to the INDANA dataset to combine joint model estimates of systolic blood pressure with time to death, time to myocardial infarction, and time to stroke. Results are compared to meta-analyses of separate longitudinal or time-to-event models. A simulation study is conducted to contrast separate versus joint analyses over a range of scenarios. Using the real dataset, similar results were obtained by using the separate and joint analyses. However, the simulation study indicated a benefit of use of joint rather than separate methods in a meta-analytic setting where association exists between the longitudinal and time-to-event outcomes. Where evidence of association between longitudinal and time-to-event outcomes exists, results from joint models over standalone analyses should be pooled in 2-stage meta-analyses. © 2017 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.
A retrospective clinico-pathological study comparing lichen planus pigmentosus with ashy dermatosis.
Cheng, Hui Mei; Chuah, Sai Yee; Gan, Emily Yiping; Jhingan, Anjali; Thng, Steven Tien Guan
2018-04-10
Controversy persists as to whether lichen planus pigmentosus and ashy dermatosis are separate clinical entities. This study was conducted to examine the clinicopathological features and treatment outcome of the two conditions. A retrospective medical chart review of all patients who were diagnosed with lichen planus pigmentosus or ashy dermatosis was conducted. The information collected included the participants' age at onset, site of onset, duration of disease, presence of precipitating factors, distribution of disease, pigmentation and presence of symptoms. In patients from whom a biopsy was taken the histopathological reports were included. Altogether 26 patients with ashy dermatosis and 29 with lichen planus pigmentosus were included in the study. Compared with ashy dermatosis, lichen planus pigmentosus had a more localised distribution with a preponderance for facial involvement, compared with the truncal preponderance in ashy dermatosis. Ashy dermatosis tended to have a more stable clinical course than lichen planus pigmentosus, which was more likely to wax and wane. The utility of histopathology in differentiating between the two conditions is low. Ashy dermatosis and lichen planus pigmentosus, as defined in this study, appear to be two separate clinical entities with distinguishable clinical features and natural histories. © 2018 The Australasian College of Dermatologists.
Investigation related to hydrogen isotopes separation by cryogenic distillation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bornea, A.; Zamfirache, M.; Stefanescu, I.
2008-07-15
Research conducted in the last fifty years has shown that one of the most efficient techniques of removing tritium from the heavy water used as moderator and coolant in CANDU reactors (as that operated at Cernavoda (Romania)) is hydrogen cryogenic distillation. Designing and implementing the concept of cryogenic distillation columns require experiments to be conducted as well as computer simulations. Particularly, computer simulations are of great importance when designing and evaluating the performances of a column or a series of columns. Experimental data collected from laboratory work will be used as input for computer simulations run at larger scale (formore » The Pilot Plant for Tritium and Deuterium Separation) in order to increase the confidence in the simulated results. Studies carried out were focused on the following: - Quantitative analyses of important parameters such as the number of theoretical plates, inlet area, reflux flow, flow-rates extraction, working pressure, etc. - Columns connected in series in such a way to fulfil the separation requirements. Experiments were carried out on a laboratory-scale installation to investigate the performance of contact elements with continuous packing. The packing was manufactured in our institute. (authors)« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vahdat, Nader
2013-09-30
The project provided hands-on training and networking opportunities to undergraduate students in the area of carbon dioxide (CO2) capture and transport, through fundamental research study focused on advanced separation methods that can be applied to the capture of CO2 resulting from the combustion of fossil-fuels for power generation . The project team’s approach to achieve its objectives was to leverage existing Carbon Capture and Storage (CCS) course materials and teaching methods to create and implement an annual CCS short course for the Tuskegee University community; conduct a survey of CO2 separation and capture methods; utilize data to verify and developmore » computer models for CO2 capture and build CCS networks and hands-on training experiences. The objectives accomplished as a result of this project were: (1) A comprehensive survey of CO2 capture methods was conducted and mathematical models were developed to compare the potential economics of the different methods based on the total cost per year per unit of CO2 avoidance; and (2) Training was provided to introduce the latest CO2 capture technologies and deployment issues to the university community.« less
Brody, Gene H; Chen, Yi-fu; Kogan, Steven M; Yu, Tianyi; Molgaard, Virginia K; DiClemente, Ralph J; Wingood, Gina M
2012-01-01
The present research addressed the following important question in pediatric medicine: Can participation in a new family-centered preventive intervention, the Strong African American Families-Teen (SAAF-T) program, deter conduct problems, substance use, substance use problems, and depressive symptoms among rural black adolescents across 22 months? Data were collected from 502 black families in rural Georgia, assigned randomly to SAAF-T or an attention control condition. The prevention condition consisted of 5 consecutive meetings at community facilities with separate, concurrent sessions for caregivers and adolescents followed by a caregiver-adolescent session in which families practiced skills they learned in the separate sessions. Adolescents self-reported conduct problem behaviors, substance use, substance use problems, and depressive symptoms at ages 16 years (pretest) and 17 years 10 months (long-term assessment). Adolescents who participated in SAAF-T evinced lower increases in conduct problem behavior, substance use, substance use problems, and depressive symptom frequencies than did adolescents in the attention control condition across the 22 months between pretest and long-term assessment. This is the first study to demonstrate efficacy in a prevention program designed to deter conduct problems, substance use, substance use problems, and depressive symptoms among rural black adolescents. Because SAAF-T is a manualized, structured program, it can be easily disseminated to public health agencies, schools, churches, boys' and girls' clubs, and other community organizations.
NASA Astrophysics Data System (ADS)
Warchoł, A.
2013-12-01
The following article presents an analysis of accuracy three point clouds (airborne, terrestrial and mobile) obtained for the same area. The study was conducted separately for the coordinates (X, Y) - examining the location of buildings vertex and separately for the coordinate (Z) - comparing models built on each of the clouds. As a baseline measurement for both analyzes (X, Y and Z), the total station measurement was taken.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jubin, R.T.
The Chemical and Energy Research Section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within six major areas of research: Hot Cell Operations, Process Chemistry and thermodynamics, Separations and Materials Synthesis, Solution Thermodynamics, biotechnology Research, and Molecular Studies. The name of a technical contact is included with each task described, and readers are encouraged to contact these individuals if they need additional information.
Zhang, Xiaowei; Sahraei, Elham; Wang, Kai
2016-01-01
Separator integrity is an important factor in preventing internal short circuit in lithium-ion batteries. Local penetration tests (nail or conical punch) often produce presumably sporadic results, where in exactly similar cell and test set-ups one cell goes to thermal runaway while the other shows minimal reactions. We conducted an experimental study of the separators under mechanical loading, and discovered two distinct deformation and failure mechanisms, which could explain the difference in short circuit characteristics of otherwise similar tests. Additionally, by investigation of failure modes, we provided a hypothesis about the process of formation of local “soft short circuits” in cells with undetectable failure. Finally, we proposed a criterion for predicting onset of soft short from experimental data. PMID:27581185
Supercritical water oxidation - Microgravity solids separation
NASA Technical Reports Server (NTRS)
Killilea, William R.; Hong, Glenn T.; Swallow, Kathleen C.; Thomason, Terry B.
1988-01-01
This paper discusses the application of supercritical water oxidation (SCWO) waste treatment and water recycling technology to the problem of waste disposal in-long term manned space missions. As inorganic constituents present in the waste are not soluble in supercritical water, they must be removed from the organic-free supercritical fluid reactor effluent. Supercritical water reactor/solids separator designs capable of removing precipitated solids from the process' supercritical fluid in zero- and low- gravity environments are developed and evaluated. Preliminary experiments are then conducted to test the concepts. Feed materials for the experiments are urine, feces, and wipes with the addition of reverse osmosis brine, the rejected portion of processed hygiene water. The solid properties and their influence on the design of several oxidation-reactor/solids-separator configurations under study are presented.
Murase, Noriaki; Murayama, Takehiko; Nishikizawa, Shigeo; Sato, Yuriko
2017-10-01
Many cities in Indonesia are under pressure to reduce solid waste and dispose of it properly. In response to this pressure, the Japan International Cooperation Agency and the Indonesian Government have implemented a solid waste separation and collection project to reduce solid waste in the target area (810 households) of Balikpapan City. We used a cluster randomised controlled trial method to measure the impact of awareness-raising activities that were introduced by the project on residents' organic solid waste separation behaviour. The level of properly separated organic solid waste increased by 6.0% in areas that conducted awareness-raising activities. Meanwhile, the level decreased by 3.6% in areas that did not conduct similar activities. Therefore, in relative comparison, awareness-raising increased the level by 9.6%. A comparison among small communities in the target area confirmed that awareness-raising activities had a significant impact on organic solid waste separation. High frequencies of monitoring at waste stations and door-to-door visits by community members had a positive impact on organic solid waste separation. A correlation between the proximity of environmental volunteers' houses to waste stations and a high level of separation was also confirmed. The awareness-raising activities introduced by the project led to a significant increase in the separation of organic solid waste.
Hiesgen, Renate; Helmly, Stefan; Galm, Ines; Morawietz, Tobias; Handl, Michael; Friedrich, K. Andreas
2012-01-01
The conductivity of fuel cell membranes as well as their mechanical properties at the nanometer scale were characterized using advanced tapping mode atomic force microscopy (AFM) techniques. AFM produces high-resolution images under continuous current flow of the conductive structure at the membrane surface and provides some insight into the bulk conducting network in Nafion membranes. The correlation of conductivity with other mechanical properties, such as adhesion force, deformation and stiffness, were simultaneously measured with the current and provided an indication of subsurface phase separations and phase distribution at the surface of the membrane. The distribution of conductive pores at the surface was identified by the formation of water droplets. A comparison of nanostructure models with high-resolution current images is discussed in detail. PMID:24958429
Wu, Juanfang; Xu, Kerui; Landers, James P.; Weber, Stephen G.
2013-01-01
We demonstrate an all-electric sampling/derivatization/separation/detection system for the quantitation of thiols in tissue cultures. Extracellular fluid collected from rat organotypic hippocampal slice cultures (OHSCs) by electroosmotic flow through an11 cm (length) × 50 μm (ID) sampling capillary is introduced to a simple microfluidic chip for derivatization, continuous flow-gated injection, separation and detection.With the help of a fluorogenic, thiol-specific reagent, ThioGlo-1, we have successfully separated and detected the extracellular levels of free reduced cysteamine, homocysteineand cysteinefrom OHSCs within 25 s in a 23 mm separation channel with a confocal laser induced fluorescence (LIF) detector. Attention to the conductivities of the fluids being transported is required for successful flow-gated injections.When the sample conductivity is much higher than the run buffer conductivities, the electroosmotic velocities are such that there is less fluid coming by electroosmosis into the cross from the sample/reagent channel than is leaving by electroosmosis into the separation and waste channels. The resulting decrease in the internal fluid pressure in the injection cross pulls flow from the gated channel. This process may completely shut down the gated injection. Using a glycylglycine buffer with physiological osmolarity but only 62% of physiological conductivity and augmenting the conductivity of the run buffers solved this problem. Quantitation is by standard additions. Concentrations of cysteamine, homocysteine and cysteine in the extracellular space of OHSCs are10.6±1.0 nM (n=70), 0.18±0.01 μM (n=53) and 11.1±1.2 μM (n=70), respectively. This is the first in situquantitative estimation of endogenous cysteamine in brain. Extracellular levels of homocysteine and cysteine are comparable with other reported values. PMID:23330713
Separator development and testing of nickel-hydrogen cells
NASA Technical Reports Server (NTRS)
Gonzalez-Sanabria, O. D.; Manzo, M. A.
1984-01-01
The components, design, and operating characteristics of Ni-H2 cells batteries were improved. A separator development program was designed to develop a separator that is resistant to penetration by oxygen and loose active material from then nickel electrode, while retraining the required chemical and thermal stability, reservoir capability, and high ionic conductivity. The performance of the separators in terms of cell operating voltage was to at least match that of state-of-the-art separators while eliminating the separator problems. The separators were submitted to initial screening tests and those which successfully completed the tests were built into Ni-H2 cells for short term testing. The separators with the best performance are tested for long term performance and life.
Land Vehicle Tire Qualification
2010-03-25
separation -Bead damage / separation -Severe open splices and/or liner separations - Tire induced loss of air -Exposed or broken casing -Bulges in tread ...or sidewall *UNCLASSIFIED* SAE J2014 11 SAE J2014 4.14 Tire Treadlife Durability -10000 miles duration -Evaluate tread wear performance of candidate... tire -Measurements at prescribed intervals - Tread depth at centerline & shoulder -Diameter, section width, tread arc width -Conducted on courses
Distillation process using microchannel technology
Tonkovich, Anna Lee [Dublin, OH; Simmons, Wayne W [Dublin, OH; Silva, Laura J [Dublin, OH; Qiu, Dongming [Carbondale, IL; Perry, Steven T [Galloway, OH; Yuschak, Thomas [Dublin, OH; Hickey, Thomas P [Dublin, OH; Arora, Ravi [Dublin, OH; Smith, Amanda [Galloway, OH; Litt, Robert Dwayne [Westerville, OH; Neagle, Paul [Westerville, OH
2009-11-03
The disclosed invention relates to a distillation process for separating two or more components having different volatilities from a liquid mixture containing the components. The process employs microchannel technology for effecting the distillation and is particularly suitable for conducting difficult separations, such as the separation of ethane from ethylene, wherein the individual components are characterized by having volatilities that are very close to one another.
NASA Astrophysics Data System (ADS)
Morozovska, Anna N.; Kurchak, Anatolii I.; Strikha, Maksym V.
2017-11-01
p -n junctions in graphene on ferroelectric substrates have been actively studied, but the impact of the piezoelectric effect in ferroelectric substrate with ferroelectric domain walls (FDWs) on graphene characteristics was not considered. Because of the piezoeffect, ferroelectric domain stripes with opposite spontaneous polarizations elongate or contract depending on the polarity of voltage applied to the substrate. We show that the alternating piezoelectric displacement of the ferroelectric domain surfaces can lead to the alternate stretching and separation of graphene areas at the steps between elongated and contracted domains. Graphene separation at FDWs induced by the piezoeffect can cause unusual effects. In particular, the conductance of the graphene channel in a field-effect transistor increases significantly because electrons in the stretched section scatter on acoustic phonons. At the same time, the graphene conductance is determined by ferroelectric spontaneous polarization and varies greatly in the presence of FDWs. The revealed piezomechanism of graphene conductance control is promising for next generations of graphene-based field-effect transistors, modulators, electrical transducers, and piezoresistive elements. Also, our results propose the method of suspended graphene fabrication based on the piezoeffect in a ferroelectric substrate that does not require any additional technological procedures.
Public opinion about the source separation of municipal solid waste in Shanghai, China.
Zhang, Weiqian; Che, Yue; Yang, Kai; Ren, Xiangyu; Tai, Jun
2012-12-01
For decades the generation of municipal solid waste (MSW) in Shanghai has been increasing. Despite the long-time efforts aimed at MSW management (MSWM), the disposal of MSW achieves poor performance. Thus, a MSW minimisation plan for Shanghai was proposed in December 2010. In this study, direct face-to-face interviews and a structured questionnaire survey were used in four different Shanghai community types. We conducted an econometric analysis of the social factors that influence the willingness to pay for MSW separation and discussed the household waste characteristics, the daily waste generation and the current treatment of kitchen wastes. The results suggested that the respondents are environmentally aware of separation, but only practise minimal separation. Negative neighbour effects, confused classification of MSW, and mixed transportation and disposal are the dominant limitations of MSW source-separated collection. Most respondents are willing to pay for MSWM. Public support is influenced by household population, income and cost. The attitudes and behaviours of citizens are important for reducing the amount of MSW disposal by 50% per capita by 2020 (relative to 2010). Concerted efforts should be taken to enlarge pilot areas. In addition, the source separation of kitchen wastes should be promoted.
Inorganic-organic separators for alkaline batteries
NASA Technical Reports Server (NTRS)
Sheibley, D. W. (Inventor)
1978-01-01
A flexible separator is reported for use between the electrodes of Ni-Cd and Ni-Zn batteries using alkaline electrolytes. The separator was made by coating a porous substrate with a battery separator composition. The coating material included a rubber-based resin copolymer, a plasticizer and inorganic and organic fillers which comprised 55% by volume or less of the coating as finally dried. One or more of the filler materials, whether organic or inorganic, is preferably active with the alkaline electrolyte to produce pores in the separator coating. The plasticizer was an organic material which is hydrolyzed by the alkaline electrolyte to improve conductivity of the separator coating.
Flotability and flotation separation of polymer materials modulated by wetting agents.
Wang, Hui; Wang, Chong-qing; Fu, Jian-gang; Gu, Guo-hua
2014-02-01
The surface free energy, surface tension and contact angles were performed to investigate the properties of wetting agents. Adsorption of wetting agents changes wetting behavior of polymer resins. Flotability of polymer materials modulated by wetting agents was studied, and wetting agents change significantly flotability of polymer materials. The flotability decreases with increasing the concentration of wetting agents, and the wetting ability is lignin sulfonate (LS)>tannic acid (TA)>methylcellulose (MC)>triton X-100 (TX-100) (from strong to weak). There is significant difference in the flotability between polymer resins and plastics due to the presence of additives in the plastics. Flotation separation of two-component and multicomponent plastics was conducted based on the flotability modulated by wetting agents. The two-component mixtures can be efficiently separated using proper wetting agent through simple flotation flowsheet. The multicomponent plastic mixtures can be separated efficiently through multi-stage flotation using TA and LS as wetting agents, and the purity of separated component was above 94%, and the recovery was more than 93%. Copyright © 2013 Elsevier Ltd. All rights reserved.
[The CAD-S, an instrument for the assessment of adaptation to divorce - separation].
Yárnoz Yaben, Sagrario; Comino González, Priscila
2010-02-01
The CAD-S, an Instrument for the Assessment of Adaptation to Divorce - Separation. This paper presents an instrument for the evaluation of the adaptation to divorce-separation. The CAD-S is a questionnaire created in Spanish, made up of 20 items whose aim is the evaluation of the family's adaptation to divorce-separation, using one of the parents as informant. Data were collected in four different samples of divorced persons and their children from different autonomous comunities from the Spanish state. 223 parents and 160 children from divorced families took part in this study. Four factors emerged, accounting for 52.39 percent of the total variance: psychological and emotional difficulties, conflict with the ex-partner, disposition to co-parentality, and negative outcomes of separation for children. The results suggest that CAD-S appears to be a reliable and valid instrument, with high internal consistency (Cronbach's alpha) and adequate construct validity supported by its relations with measures of satisfaction with life (SWLS), in the case of parents, and conduct problems (CBCL) for children.
Advanced flight hardware for organic separations
NASA Astrophysics Data System (ADS)
Deuser, Mark S.; Vellinger, John C.; Weber, John T.
1997-01-01
Aqueous Two-Phase Partitioning (ATPP) is a unique separation technique which allows purification and classification of biological materials. SHOT has employed the ATPP process in separation equipment developed for both space and ground applications. Initial equipment development and research focused on the ORganic SEParation (ORSEP) space flight experiments that were performed on suborbital rockets and the shuttle. ADvanced SEParations (ADSEP) technology was developed as the next generation of ORSEP equipment through a NASA Small Business Innovation Research (SBIR) contract. Under the SBIR contract, a marketing study was conducted, indicating a growing commercial market exists among biotechnology firms for ADSEP equipment and associated flight research and development services. SHOT is preparing to begin manufacturing and marketing laboratory versions of the ADSEP hardware for the ground-based market. In addition, through a self-financed SBIR Phase III effort, SHOT fabricated and integrated the ADSEP flight hardware for a commercially-driven flight experiment as the initial step in marketing space processing services. The ADSEP ground-based and microgravity research is expected to play a vital role in developing important new biomedical and pharmaceutical products.
Design of A Cyclone Separator Using Approximation Method
NASA Astrophysics Data System (ADS)
Sin, Bong-Su; Choi, Ji-Won; Lee, Kwon-Hee
2017-12-01
A Separator is a device installed in industrial applications to separate mixed objects. The separator of interest in this research is a cyclone type, which is used to separate a steam-brine mixture in a geothermal plant. The most important performance of the cyclone separator is the collection efficiency. The collection efficiency in this study is predicted by performing the CFD (Computational Fluid Dynamics) analysis. This research defines six shape design variables to maximize the collection efficiency. Thus, the collection efficiency is set up as the objective function in optimization process. Since the CFD analysis requires a lot of calculation time, it is impossible to obtain the optimal solution by linking the gradient-based optimization algorithm. Thus, two approximation methods are introduced to obtain an optimum design. In this process, an L18 orthogonal array is adopted as a DOE method, and kriging interpolation method is adopted to generate the metamodel for the collection efficiency. Based on the 18 analysis results, the relative importance of each variable to the collection efficiency is obtained through the ANOVA (analysis of variance). The final design is suggested considering the results obtained from two optimization methods. The fluid flow analysis of the cyclone separator is conducted by using the commercial CFD software, ANSYS-CFX.
Determination of urine-derived odorous compounds in a source separation sanitation system.
Liu, Bianxia; Giannis, Apostolos; Chen, Ailu; Zhang, Jiefeng; Chang, Victor W C; Wang, Jing-Yuan
2017-02-01
Source separation sanitation systems have attracted more and more attention recently. However, separate urine collection and treatment could induce odor issues, especially in large scale application. In order to avoid such issues, it is necessary to monitor the odor related compounds that might be generated during urine storage. This study investigated the odorous compounds that emitted from source-separated human urine under different hydrolysis conditions. Batch experiments were conducted to investigate the effect of temperature, stale/fresh urine ratio and urine dilution on odor emissions. It was found that ammonia, dimethyl disulfide, allyl methyl sulfide and 4-heptanone were the main odorous compounds generated from human urine, with headspace concentrations hundreds of times higher than their respective odor thresholds. Furthermore, the high temperature accelerated urine hydrolysis and liquid-gas mass transfer, resulting a remarkable increase of odor emissions from the urine solution. The addition of stale urine enhanced urine hydrolysis and expedited odor emissions. On the contrary, diluted urine emitted less odorous compounds ascribed to reduced concentrations of odorant precursors. In addition, this study quantified the odor emissions and revealed the constraints of urine source separation in real-world applications. To address the odor issue, several control strategies are recommended for odor mitigation or elimination from an engineering perspective. Copyright © 2016. Published by Elsevier B.V.
Process for analyzing CO[sub 2] in air and in water
Atwater, J.E.; Akse, J.R.; DeHart, J.
1999-06-08
The process of this invention comprises providing a membrane for separating CO[sub 2] into a first CO[sub 2] sample phase and a second CO[sub 2] analyte phase. CO[sub 2] is then transported through the membrane thereby separating the CO[sub 2] with the membrane into a first CO[sub 2] sample phase and a second CO[sub 2] analyte liquid phase including an ionized, conductive, dissociated CO[sub 2] species. Next, the concentration of the ionized, conductive, dissociated CO[sub 2] species in the second CO[sub 2] analyte liquid phase is chemically amplified using a water-soluble chemical reagent which reversibly reacts with undissociated CO[sub 2] to produce conductivity changes therein corresponding to fluctuations in the partial pressure of CO[sub 2] in the first CO[sub 2] sample phase. Finally, the chemically amplified, ionized, conductive, dissociated CO[sub 2] species is introduced to a conductivity measuring instrument. Conductivity changes in the chemically amplified, ionized, conductive, dissociated CO[sub 2] species are detected using the conductivity measuring instrument. 43 figs.
Process for analyzing CO.sub.2 in air and in water
Atwater, James E.; Akse, James R.; DeHart, Jeffrey
1999-01-01
The process of this invention comprises providing a membrane for separating CO.sub.2 into a first CO.sub.2 sample phase and a second CO.sub.2 analyte phase. CO.sub.2 is then transported through the membrane thereby separating the CO.sub.2 with the membrane into a first CO.sub.2 sample phase and a second CO.sub.2 analyte liquid phase including an ionized, conductive, dissociated CO.sub.2 species. Next, the concentration of the ionized, conductive, dissociated CO.sub.2 species in the second CO.sub.2 analyte liquid phase is chemically amplified using a water-soluble chemical reagent which reversibly reacts with undissociated CO.sub.2 to produce conductivity changes therein corresponding to fluctuations in the partial pressure of CO.sub.2 in the first CO.sub.2 sample phase. Finally, the chemically amplified, ionized, conductive, dissociated CO.sub.2 species is introduced to a conductivity measuring instrument. Conductivity changes in the chemically amplified, ionized, conductive, dissociated CO.sub.2 species are detected using the conductivity measuring instrument.
Process for analyzing CO{sub 2} in seawater
Atwater, J.E.; Akse, J.R.; DeHart, J.
1997-07-01
The process of this invention comprises providing a membrane for separating CO{sub 2} into a first CO{sub 2} sample phase and a second CO{sub 2} analyte phase. CO{sub 2} is then transported through the membrane thereby separating the CO{sub 2} with the membrane into a first CO{sub 2} sample phase and a second CO{sub 2} analyte liquid phase including an ionized, conductive, dissociated CO{sub 2} species. Next, the concentration of the ionized, conductive, dissociated CO{sub 2} species in the second CO{sub 2} analyte liquid phase is chemically amplified using a water-soluble chemical reagent which reversibly reacts with undissociated CO{sub 2} to produce conductivity changes therein corresponding to fluctuations in the partial pressure of CO{sub 2} in the first CO{sub 2} sample phase. Finally, the chemically amplified, ionized, conductive, dissociated CO{sub 2} species is introduced to a conductivity measuring instrument. Conductivity changes in the chemically amplified, ionized, conductive, dissociated CO{sub 2} species are detected using the conductivity measuring instrument. 43 figs.
Five Decades of ALER Conference Session Presentations, 1960-2010
ERIC Educational Resources Information Center
Still, Kristine Lynn; Gordon, Jaclyn Prizant
2011-01-01
The purpose of this study was to conduct a quantitative content analysis of the conference session programs from the Association of Literacy Educators and Researchers (ALER) annual meetings across five decades spanning from 1960 through 2010. The data cycled through an analysis during four separate phases. In total, 4,605 conference sessions were…
Video Self-Modeling and Improving Oral Reading Fluency
ERIC Educational Resources Information Center
Chandler, Wanda Gail
2012-01-01
Self-modeling can take different forms but is described as a process where one observes one's own successful behavior and learns from it without dependence on any particular medium. In this study, two separate experiments were conducted to evaluate a video self-modeling (VSM) feedforward intervention. VSM feedforward (independent variable, IV),…
Testing common stream sampling methods for broad-scale, long-term monitoring
Eric K. Archer; Brett B. Roper; Richard C. Henderson; Nick Bouwes; S. Chad Mellison; Jeffrey L. Kershner
2004-01-01
We evaluated sampling variability of stream habitat sampling methods used by the USDA Forest Service and the USDI Bureau of Land Management monitoring program for the upper Columbia River Basin. Three separate studies were conducted to describe the variability of individual measurement techniques, variability between crews, and temporal variation throughout the summer...
The Medical Home for Children with Autism Spectrum Disorders: Parent and Pediatrician Perspectives
ERIC Educational Resources Information Center
Carbone, Paul S.; Behl, Diane D.; Azor, Virgina; Murphy, Nancy A.
2010-01-01
This qualitative study examines differences between perceptions of parents and pediatricians regarding the needs of children with autism spectrum disorders (ASDs) and their families within the medical home. Two separate focus groups of parents of children with ASDs and pediatricians were conducted. Parents and pediatricians identify unmet needs…
ERIC Educational Resources Information Center
Patrick, Helen; Kaplan, Avi; Ryan, Allison M.
2011-01-01
In a series of 4 studies we investigated the relations of mastery goal structure and 4 dimensions of the classroom social climate (teacher academic support, teacher emotional support, classroom mutual respect, task-related interaction). We conducted multidimensional scaling with separate adolescent samples that differed considerably (i.e., by…
Michael G. Shelton; Michael D. Cain
2002-01-01
Loblolly (Pinus taeda L.) and shortleaf (P. echinata Mill.) pine seedlings are frequently top damaged during their first few years by browsing animals, insects, or forestry operations, but little quantitative information exists on the factors affecting recovery. Thus, we conducted two separate studies to evaluate potential recovery...
Spatial tuning of a RF frequency selective surface through origami
NASA Astrophysics Data System (ADS)
Fuchi, Kazuko; Buskohl, Philip R.; Bazzan, Giorgio; Durstock, Michael F.; Joo, James J.; Reich, Gregory W.; Vaia, Richard A.
2016-05-01
Origami devices have the ability to spatially reconfigure between 2D and 3D states through folding motions. The precise mapping of origami presents a novel method to spatially tune radio frequency (RF) devices, including adaptive antennas, sensors, reflectors, and frequency selective surfaces (FSSs). While conventional RF FSSs are designed based upon a planar distribution of conductive elements, this leaves the large design space of the out of plane dimension underutilized. We investigated this design regime through the computational study of four FSS origami tessellations with conductive dipoles. The dipole patterns showed increased resonance shift with decreased separation distances, with the separation in the direction orthogonal to the dipole orientations having a more significant effect. The coupling mechanisms between dipole neighbours were evaluated by comparing surface charge densities, which revealed the gain and loss of coupling as the dipoles moved in and out of alignment via folding. Collectively, these results provide a basis of origami FSS designs for experimental study and motivates the development of computational tools to systematically predict optimal fold patterns for targeted frequency response and directionality.
Safety divers prepare HST mockup in the Neutral Buoyancy Simulator at MSFC
1993-06-01
Safety divers in the Neutral Buoyancy Simulator (NBS) at the Marshall Space Flight Center (MSFC) prepare a mockup of the Hubble Space Telescope (HST) for one of 32 separate training sessions conducted by four of the STS-61 crew members in June. The three-week process allowed mission trainers to refine the timelines for the five separate spacewalks scheduled to be conducted on the actual mission scheduled for December 1993. The HST is separated into two pieces since the water tank depth cannot support the entire structure in one piece. The full length payload bay mockup shows the Solar Array Carrier in the foreground and the various containers that will house replacement hardware that will be carried on the mission.
Rotary Drum Separator and Pump for the Sabatier Carbon Dioxide Reduction System
NASA Technical Reports Server (NTRS)
Holder, Don; Fort, James; Barone, Michael; Murdoch, Karen
2005-01-01
A trade study conducted in 2001 selected a rotary disk separator as the best candidate to meet the requirements for an International Space Station (ISS) Carbon Dioxide Reduction Assembly (CRA). The selected technology must provide micro-gravity gasfliquid separation and pump the liquid from 10 psia at the gasfliquid interface to 18 psia at the wastewater bus storage tank. The rotary disk concept, which has pedigree in other systems currently being built for installation on the ISS, failed to achieve the required pumping head within the allotted power. The separator discussed in this paper is a new design that was tested to determine compliance with performance requirements in the CRA. The drum separator and pump @SP) design is similar to the Oxygen Generator Assembly (OGA) Rotary Separator Accumulator (RSA) in that it has a rotating assembly inside a stationary housing driven by a integral internal motor. The innovation of the DSP is the drum shaped rotating assembly that acts as the accumulator and also pumps the liquid at much less power than its predecessors. In the CRA application, the separator will rotate at slow speed while accumulating water. Once full, the separator will increase speed to generate sufficient head to pump the water to the wastewater bus. A proof-of- concept (POC) separator has been designed, fabricated and tested to assess the separation efficiency and pumping head of the design. This proof-of-concept item was flown aboard the KC135 to evaluate the effectiveness of the separator in a microgravity environment. This separator design has exceeded all of the performance requirements. The next step in the separator development is to integrate it into the Sabatier Carbon Dioxide Reduction System. This will be done with the Sabatier Engineering Development Unit at the Johnson Space Center.
ERIC Educational Resources Information Center
Anderson, Norman D.
From 1968 to 1970, three separate studies of North Carolina science teachers were conducted in the areas of biology (N=177), chemistry (N=101), and physics (N=71). The three studies shared three major purposes, to determine: the academic preparation of the science teachers being investigated, (2) the relationship between the level of academic…
Ecological adaptations in Douglas-fir (Psuedotsuga menziesii var. glauca): a synthesis
Gerald Rehfeldt
1989-01-01
Measurements of 3rd-year height of 228 seedling populations, grown in four separate studies in two of the same common gardens, were used to summarize patterns of genetic variation for Douglas-fir across 250 000 km 2 of forested lands in Idaho and Montana, U.S.A. Because each study was conducted in different years with a different set of populations, measurements were...
ERIC Educational Resources Information Center
Harris, Lauren McArthur; Bain, Robert B.
2011-01-01
The authors are conducting studies to determine what knowledge world history teachers need and how they can use it to plan instruction. In this article, they report on a small but in-depth study designed to examine how four pre-service and six in-service world history teachers think about, organize, and make meaning of separate world historical…
ERIC Educational Resources Information Center
What Works Clearinghouse, 2012
2012-01-01
The study reviewed in this paper examined three separate methods for teaching the "control of variables strategy" ("CVS"), a procedure for conducting a science experiment so that only one variable is tested and all others are held constant, or "controlled." The study analyzed data from a randomized controlled trial of…
ERIC Educational Resources Information Center
Densmore, Glen; Bourne, Charles
This study was conducted to determine what fraction of the total cost of the Stanford University library system can properly be charged to each of the four major groups of users: undergraduate students, graduate students, faculty and staff, and non-Stanford users. Eight separate cost elements were developed for each of the library's cost centers…
ERIC Educational Resources Information Center
Hetherington, Lindsay
2010-01-01
Results of a small-scale research study conducted with year 8 (ages 12-13) students suggest that although these students have generally positive attitudes towards earth science, girls tend to be less interested in it than boys. Interest in earth science was found to separate into two dominant factors, labelled "scientific" and…
Zhang, Jianjun; Liu, Zhihong; Kong, Qingshan; Zhang, Chuanjian; Pang, Shuping; Yue, Liping; Wang, Xuejiang; Yao, Jianhua; Cui, Guanglei
2013-01-01
A renewable and superior thermal-resistant cellulose-based composite nonwoven was explored as lithium-ion battery separator via an electrospinning technique followed by a dip-coating process. It was demonstrated that such nanofibrous composite nonwoven possessed good electrolyte wettability, excellent heat tolerance, and high ionic conductivity. The cells using the composite separator displayed better rate capability and enhanced capacity retention, when compared to those of commercialized polypropylene separator under the same conditions. These fascinating characteristics would endow this renewable composite nonwoven a promising separator for high-power lithium-ion battery.
ERIC Educational Resources Information Center
Timonen, Virpi; Doyle, Martha; O'Dwyer, Ciara
2011-01-01
The literature on intergenerational transfers and divorce has paid little attention to the experiences of older adults whose son or daughter has divorced or separated. The authors conducted 31 qualitative interviews to explore support provision from the perspective of older adults with divorced or separated adult children. All respondents were…
Experimental Stage Separation Tool Development in NASA Langley's Aerothermodynamics Laboratory
NASA Technical Reports Server (NTRS)
Murphy, Kelly J.; Scallion, William I.
2005-01-01
As part of the research effort at NASA in support of the stage separation and ascent aerothermodynamics research program, proximity testing of a generic bimese wing-body configuration was conducted in NASA Langley's Aerothermodynamics Laboratory in the 20-Inch Mach 6 Air Tunnel. The objective of this work is the development of experimental tools and testing methodologies to apply to hypersonic stage separation problems for future multi-stage launch vehicle systems. Aerodynamic force and moment proximity data were generated at a nominal Mach number of 6 over a small range of angles of attack. The generic bimese configuration was tested in a belly-to-belly and back-to-belly orientation at 86 relative proximity locations. Over 800 aerodynamic proximity data points were taken to serve as a database for code validation. Longitudinal aerodynamic data generated in this test program show very good agreement with viscous computational predictions. Thus a framework has been established to study separation problems in the hypersonic regime using coordinated experimental and computational tools.
Zuin, Vânia G; Ramin, Luize Z
2018-01-17
New generations of biorefinery combine innovative biomass waste resources from different origins, chemical extraction and/or synthesis of biomaterials, biofuels, and bioenergy via green and sustainable processes. From the very beginning, identifying and evaluating all potentially high value-added chemicals that could be removed from available renewable feedstocks requires robust, efficient, selective, reproducible, and benign analytical approaches. With this in mind, green and sustainable separation of natural products from agro-industrial waste is clearly attractive considering both socio-environmental and economic aspects. In this paper, the concepts of green and sustainable separation of natural products will be discussed, highlighting the main studies conducted on this topic over the last 10 years. The principal analytical techniques (such as solvent, microwave, ultrasound, and supercritical treatments), by-products (e.g., citrus, coffee, corn, and sugarcane waste) and target compounds (polyphenols, proteins, essential oils, etc.) will be presented, including the emerging green and sustainable separation approaches towards bioeconomy and circular economy contexts.
Investigations on gel forming media use in low gravity bioseparations research
NASA Technical Reports Server (NTRS)
Todd, Paul; Szlag, David C.; Plank, Lindsay D.; Delcourt, Scott G.; Kunze, M. Elaine
1989-01-01
Research on gelling media and conditions suitable for the preservation of the spatial configuration of cell suspensions and macromolecular solutions after separation in free fluid during low gravity experiments is presented. The examples studied included free electrophoresis of cells in a cylindrical column and two-phase aqueous polymer separation. Microgravity electrophoresis experiments were simulated by separating model cell types (animal or human) in a vertical density gradient containing low-conductivity buffer, 1.7-6.5 percent Ficoll, 6.8-5.0 percent sucrose, and 1 percent SeaPrep low-melting temperature agarose. Upon cooling, a gel formed in the column and cells could be captured at the forming locations. Two-phase extraction experiments were simulated using two-polymer solutions in which phase separation occurs in normal saline at temperatures compatible with cell viability and in which one or both phases form a gel upon cooling. Suitable polymers included commercial agaroses (1-2 percent), maltodextrin (5-7 percent), and gelatin (5-20 percent).
Study on reduction and back extraction of Pu(IV) by urea derivatives in nitric acid conditions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ye, G.A.; Xiao, S.T.; Yan, T.H.
2013-07-01
The reduction kinetics of Pu(IV) by hydroxyl-semicarbazide (HSC), hydroxyurea (HU) and di-hydroxyurea (DHU) in nitric acid solutions were investigated separately with adequate kinetic equations. In addition, counter-current cascade experiments were conducted for Pu split from U in nitric acid media using three kinds of reductant, respectively. The results show that urea derivatives as a kind of novel salt-free reductant can reduce Pu(IV) to Pu(III) rapidly in the nitric acid solutions. The stripping experimental results showed that Pu(IV) in the organic phase can be stripped rapidly to the aqueous phase by the urea derivatives, and the separation factors of plutonium /uraniummore » can reach more than 10{sup 4}. This indicates that urea derivatives is a kind of promising salt-free agent for uranium/plutonium separation. In addition, the complexing effect of HSC with Np(IV) was revealed, and Np(IV) can be back-extracted by HSC with a separation factor of about 20.« less
Functional Allocation for Ground-Based Automated Separation Assurance in NextGen
NASA Technical Reports Server (NTRS)
Prevot, Thomas; Mercer, Joey; Martin, Lynne; Homola, Jeffrey; Cabrall, Christopher; Brasil, Connie
2010-01-01
As part of an ongoing research effort into functional allocation in a NextGen environment, a controller-in-the-loop study on ground-based automated separation assurance was conducted at NASA Ames' Airspace Operations Laboratory in February 2010. Participants included six FAA front line managers, who are currently certified professional controllers and four recently retired controllers. Traffic scenarios were 15 and 30 minutes long where controllers interacted with advanced technologies for ground-based separation assurance, weather avoidance, and arrival metering. The automation managed the separation by resolving conflicts automatically and involved controllers only by exception, e.g., when the automated resolution would have been outside preset limits. Results from data analyses show that workload was low despite high levels of traffic, Operational Errors did occur but were closely tied to local complexity, and safety acceptability ratings varied with traffic levels. Positive feedback was elicited for the overall concept with discussion on the proper allocation of functions and trust in automation.
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.
Effect of Branching on Rod-coil Polyimides as Membrane Materials for Lithium Polymer Batteries
NASA Technical Reports Server (NTRS)
Meador, Mary Ann B.; Cubon, Valerie A.; Scheiman, Daniel A.; Bennett, William R.
2003-01-01
This paper describes a series of rod-coil block co-polymers that produce easy to fabricate, dimensionally stable films with good ionic conductivity down to room temperature for use as electrolytes for lithium polymer batteries. The polymers consist of short, rigid rod polyimide segments, alternating with flexible, polyalkylene oxide coil segments. The highly incompatible rods and coils should phase separate, especially in the presence of lithium ions. The coil phase would allow for conduction of lithium ions, while the rigid rod phase would provide a high degree of dimensional stability. An optimization study was carried out to study the effect of four variables (degree of branching, formulated molecular weight, polymerization solvent and lithium salt concentration) on ionic conductivity, glass transition temperature and dimensional stability in this system.
Maity, Partha; Debnath, Tushar; Chopra, Uday; Ghosh, Hirendra Nath
2015-02-14
Ultrafast cascading hole and electron transfer dynamics have been demonstrated in a CdS/CdTe type II core-shell sensitized with Br-PGR using transient absorption spectroscopy and the charge recombination dynamics have been compared with those of CdS/Br-PGR composite materials. Steady state optical absorption studies suggest that Br-PGR forms strong charge transfer (CT) complexes with both the CdS QD and CdS/CdTe core-shell. Hole transfer from the photo-excited QD and QD core-shell to Br-PGR was confirmed by both steady state and time-resolved emission spectroscopy. Charge separation was also confirmed by detecting electrons in the conduction band of the QD and the cation radical of Br-PGR as measured from femtosecond transient absorption spectroscopy. Charge separation in the CdS/Br-PGR composite materials was found to take place in three different pathways, by transferring the photo-excited hole of CdS to Br-PGR, electron injection from the photo-excited Br-PGR to the CdS QD, and direct electron transfer from the HOMO of Br-PGR to the conduction band of the CdS QD. However, in the CdS/CdTe/Br-PGR system hole transfer from the photo-excited CdS to Br-PGR and electron injection from the photo-excited Br-PGR to CdS take place after cascading through the CdTe shell QD. Charge separation also takes place via direct electron transfer from the Br-PGR HOMO to the conduction band of CdS/CdTe. Charge recombination (CR) dynamics between the electron in the conduction band of the CdS QD and the Br-PGR cation radical were determined by monitoring the bleach recovery kinetics. The CR dynamics were found to be much slower in the CdS/CdTe/Br-PGR system than in the CdS/Br-PGR system. The formation of the strong CT complex and the separation of charges cascading through the CdTe shell help to slow down charge recombination in the type II regime.
Metal separations using aqueous biphasic partitioning systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chaiko, D.J.; Zaslavsky, B.; Rollins, A.N.
1996-05-01
Aqueous biphasic extraction (ABE) processes offer the potential for low-cost, highly selective separations. This countercurrent extraction technique involves selective partitioning of either dissolved solutes or ultrafine particulates between two immiscible aqueous phases. The extraction systems that the authors have studied are generated by combining an aqueous salt solution with an aqueous polymer solution. They have examined a wide range of applications for ABE, including the treatment of solid and liquid nuclear wastes, decontamination of soils, and processing of mineral ores. They have also conducted fundamental studies of solution microstructure using small angle neutron scattering (SANS). In this report they reviewmore » the physicochemical fundamentals of aqueous biphase formation and discuss the development and scaleup of ABE processes for environmental remediation.« less
Holistic Experiences and Strategies for Conducting Research With Couples.
Braybrook, Debbie E; Mróz, Lawrence W; Robertson, Steve; White, Alan; Milnes, Kate
2017-03-01
In this article, we outline methodological considerations for conducting research interviews with couples. We draw from two qualitative men's health studies, both developed to explore social interactions between men and their partners of either sex in relation to their health practices. We utilized a combination of separate interviews and joint couple interviews. From these studies, we offer insight into our experiences of using both types of interview styles, addressing four key areas which span elements across the research project journey: (a) choosing a mode of interview, (b) ethical concerns in couple research, (c) the interview as a platform for disclosure, and (d) analyzing data from couple research.
Microchip Electrophoresis at Elevated Temperatures and High Separation Field Strengths
Mitra, Indranil; Marczak, Steven P.; Jacobson, Stephen C.
2014-01-01
We report free-solution microchip electrophoresis performed at elevated temperatures and high separation field strengths. We used microfluidic devices with 11-cm long separation channels to conduct separations at temperatures between 22 (ambient) and 45 °C and field strengths from 100 to 1000 V/cm. To evaluate separation performance, N-glycans were used as a model system and labeled with 8-aminopyrene-1,3,6-trisulfonic acid to impart charge for electrophoresis and render them fluorescent. Typically, increased diffusivity at higher temperatures leads to increased axial dispersion and poor separation performance; however, we demonstrate that sufficiently high separation field strengths can be used to offset the impact of increased diffusivity in order to maintain separation efficiency. Efficiencies for these free-solution separations are the same at temperatures of 25, 35, and 45 °C with separation field strengths ≥500 V/cm. PMID:24114979
NASA Astrophysics Data System (ADS)
Liang, Yinzheng; Ji, Liwen; Guo, Bingkun; Lin, Zhan; Yao, Yingfang; Li, Ying; Alcoutlabi, Mataz; Qiu, Yiping; Zhang, Xiangwu
Lithium lanthanum titanate oxide (LLTO)/polyacrylonitrile (PAN) submicron composite fiber-based membranes were prepared by electrospinning dispersions of LLTO ceramic particles in PAN solutions. These ionic-conducting LLTO/PAN composite fiber-based membranes can be directly used as lithium-ion battery separators due to their unique porous structure. Ionic conductivities were evaluated after soaking the electrospun LLTO/PAN composite fiber-based membranes in a liquid electrolyte, 1 M lithium hexafluorophosphate (LiPF 6) in ethylene carbonate (EC)/ethyl methyl carbonate (EMC) (1:1 vol). It was found that, among membranes with various LLTO contents, 15 wt.% LLTO/PAN composite fiber-based membranes provided the highest ionic conductivity, 1.95 × 10 -3 S cm -1. Compared with pure PAN fiber membranes, LLTO/PAN composite fiber-based membranes had greater liquid electrolyte uptake, higher electrochemical stability window, and lower interfacial resistance with lithium. In addition, lithium//1 M LiPF 6/EC/EMC//lithium iron phosphate cells containing LLTO/PAN composite fiber-based membranes as the separator exhibited high discharge specific capacity of 162 mAh g -1 and good cycling performance at 0.2 C rate at room temperature.
Advanced ballistic range technology
NASA Technical Reports Server (NTRS)
Yates, Leslie A.
1994-01-01
The research conducted supported two facilities at NASA Ames Research Center: the Hypervelocity Free-Flight Aerodynamic Facility and the 16-Inch Shock Tunnel. During the grant period, a computerized film-reading system was developed, and five- and six-degree-of-freedom parameter-identification routines were written and successfully implemented. Studies of flow separation were conducted, and methods to extract phase shift information from finite-fringe interferograms were developed. Methods for constructing optical images from Computational Fluid Dynamics solutions were also developed, and these methods were used for one-to-one comparisons of experiment and computations.
Effect of polyvinylpyrrolidone content on alternating current conductivity of polyaniline
NASA Astrophysics Data System (ADS)
Megha, R.; Kumar, T. G. Naveen; Ravikiran, Y. T.; Prakash, H. G. Raj; Revanasiddappa, M.; Kumari, S. C. Vijaya
2018-05-01
In the present work, Polyaniline (PANI) and Polyaniline-polyvinylpyrrolidone (PANI-PVP) composites of two different weight percentages of PVP were synthesized separately by simple chemical polymerization method. The interaction between PANI and PVP in each of the composite was confirmed by Attenuated total reflection infrared spectroscopic (AT-IR) technique. The alternate current (AC) response characteristics at room temperature of PANI and the composites in the frequency range 50 Hz-1 MHz were comparatively studied. Both the composites have shown decreased conductivity as compared to that of PANI.
NASA Astrophysics Data System (ADS)
Rabbi, Fazle
Dense mixed ionic-electronic conducting (MIEC) membranes consisting of ionic conductive perovskite-type and/or fluorite-type oxides and high electronic conductive spinel type oxides, at elevated temperature can play a useful role in a number of energy conversion related systems including the solid oxide fuel cell (SOFC), oxygen separation and permeation membranes, partial oxidization membrane reactors for natural gas processing, high temperature electrolysis cells, and others. This study will investigate the impact of different heterogeneous characteristics of dual phase ionic and electronic conductive oxygen separation membranes on their transport mechanisms, in an attempt to develop a foundation for the rational design of such membranes. The dielectric behavior of a material can be an indicator for MIEC performance and can be incorporated into computational models of MIEC membranes in order to optimize the composition, microstructure, and ultimately predict long term membrane performance. The dielectric behavior of the MIECs can also be an indicator of the transport mechanisms and the parameters they are dependent upon. For this study we chose a dual phase MIEC oxygen separation membrane consisting of an ionic conducting phase: gadolinium doped ceria-Ce0.8 Gd0.2O2 (GDC) and an electronic conductive phase: cobalt ferrite-CoFe2O4 (CFO). The membranes were fabricated from mixtures of Nano-powder of each of the phases for different volume percentages, sintered with various temperatures and sintering time to form systematic micro-structural variations, and characterized by structural analysis (XRD), and micro-structural analysis (SEM-EDS). Performance of the membranes was tested for variable partial pressures of oxygen across the membrane at temperatures from 850°C-1060°C using a Gas Chromatography (GC) system. Permeated oxygen did not directly correlate with change in percent mixture. An intermediate mixture 60%GDC-40%CFO had the highest flux compared to the 50%GDC-50%CFO and 80%GDC-20%CFO mixtures. Material characterization suggests the emergence of a third phase contributing to the behavior. Microstructural studies suggested changes in micro-structure of a given volume fraction for different sintering temperature and sintering time. Flux variation was observed for membranes with the same constituent volume fraction but different micro-structure indicating the effects of the micro-structure on the overall oxygen permeation. To correlate the experimental flux measurement with a standard Wagner's flux equation, different microstructural characteristics were studied to incorporate them into a modified Wagner's flux equation. In-situ broadband dielectric spectroscopy measurements over a temperature range of 850°C-1060°C and frequency range of (0.1Hz-1MHz) of the operating 60%GDC-40%CFO mixture oxygen separation membranes were measured using a NOVOCONTROL dielectric spectroscopy test system. Dielectric response of the operating membrane was studied to identify the charge transfer process in the membrane. A computational model to study the dielectric impedance response of different microstructure was developed using a COMSOL(TM) Multiphysics qasi-static electromagnetic module. This model was validated using model materials with regular geometric shapes. To measure impedance of real micro/nano-structures of the membrane material, domains required for the COMSOL calculation were obtained from actual micro/nano structures by using 3D scans from X-ray nano and micro tomography. Simpleware(TM) software was used to generate 3D domains from image slices obtained from the 3D x-ray scans. Initial voltage distributions on the original microstructure were obtained from the computational model. Similarly, development of a primary model for simulating ionic/electronic species flow inside of an MIEC was also begun. The possibility of using broadband dielectric spectroscopy methods to understand and anticipate the flux capabilities of MIECs to reduce the cost and time of development of such material systems was explored.
Thermal Properties of SiOC Glasses and Glass Ceramics at Elevated Temperatures
Stabler, Christina; Reitz, Andreas; Stein, Peter; Albert, Barbara; Riedel, Ralf
2018-01-01
In the present study, the effect of the chemical and phase composition on the thermal properties of silicon oxide carbides (SiOC) has been investigated. Dense monolithic SiOC materials with various carbon contents were prepared and characterized with respect to their thermal expansion, as well as thermal conductivity. SiOC glass has been shown to exhibit low thermal expansion (e.g., ca. 3.2 × 10−6 K−1 for a SiOC sample free of segregated carbon) and thermal conductivity (ca. 1.5 W/(m∙K)). Furthermore, it has been observed that the phase separation, which typically occurs in SiOC exposed to temperatures beyond 1000–1200 °C, leads to a decrease of the thermal expansion (i.e., to 1.83 × 10−6 K−1 for the sample above); whereas the thermal conductivity increases upon phase separation (i.e., to ca. 1.7 W/(m∙K) for the sample mentioned above). Upon adjusting the amount of segregated carbon content in SiOC, its thermal expansion can be tuned; thus, SiOC glass ceramics with carbon contents larger than 10–15 vol % exhibit similar coefficients of thermal expansion to that of the SiOC glass. Increasing the carbon and SiC content in the studied SiOC glass ceramics leads to an increase in their thermal conductivity: SiOC with relatively large carbon and silicon carbides (SiC) volume fractions (i.e., 12–15 and 20–30 vol %, respectively) were shown to possess thermal conductivities in the range from 1.8 to 2.7 W/(m∙K). PMID:29439441
Fractionation of mineral species by electrophoresis
NASA Technical Reports Server (NTRS)
Dunning, J. D.; Herren, B. J.; Tipps, R. W.; Snyder, R. S.
1982-01-01
The fractionation of fine-grained aggregates into their major components is a problem in many scientific areas including earth and planetary science. Electrophoresis, the transport of electrically charged particles, immersed in a suspension medium, by a direct current field (Bier, 1959), was employed in this study as a means of separating simulated lunar soil into its constituent minerals. In these tests, conducted in a static analytical cylindrical microelectrophoresis apparatus, samples of simulated lunar soil and samples of pure mineral constituents were placed in the chamber; the electrophoretic mobilities of the lunar soil and the individual mineral constituents were measured. In most of the suspension buffers employed separability was indicated, on the basis of differences in mobility, for all the constituent mineral species except ilmenite and pyroxene, which were not efficiently separable in any of the buffers. Although only a few suspension media were employed, the success of this initial study suggests that electrophoresis may be an important mineral fractionation option in fine-grained aggregate processing.
Separation dynamics of dense dispersions in laminar pipe flows: An experimental and numerical study
NASA Astrophysics Data System (ADS)
Voulgaropoulos, Victor; Jamshidi, Rashid; Zainal Abidin, M. I. I.; Angeli, Panagiota
2017-11-01
The physical mechanisms governing the separation of dense liquid dispersed flows in pipes are not well understood. In this work, both experiments and numerical simulations are performed to investigate these mechanisms. Liquid-liquid dispersions are generated using a static mixer and their evolution is studied along a horizontal pipe (26mm ID) at laminar flow and input dispersed phase volume fractions up to 50%. To conduct optical measurements (PLIF and PIV) in the dense dispersions, the refractive index of both liquids is matched. Measurements are carried out at two axial locations downstream the mixer (15D and 135D, where D is the pipe diameter). Homogeneous dispersions, observed at 15D, segregate at 135D. The packing of the drops results in asymmetric velocity profiles and high slip velocities. The mixture approach is used in the numerical simulations, including gravity and shear-induced diffusion of drops. The predictions on separation and on velocity fields agree well with the experiments. Research funded by Chevron.
Exploring the Parameters Controlling the Crystallinity-Conductivity Correlation of PFSA Ionomers
NASA Astrophysics Data System (ADS)
Kusoglu, Ahmet; Shi, Shouwen; Weber, Adam
Perfluorosulfonic-acid (PFSA) ionomers are the most commonly used solid-electrolyte in electrochemical energy devices because of their remarkable conductivity and chemical/mechanical stability, with the latter imparted by their semi-crystalline fluorocarbon backbone. PFSAs owe this unique combination of transport/stability functionalities to their phase-separated morphology of conductive hydrophilic ionic domains and the non-conductive hydrophobic backbone, which are connected via pendant chains. Thus, phase-separation is governed by fractions of backbone and ionic groups, which is controlled by the equivalent weight (EW). Therefore, EW, along with the pendant chain chemistry, directly impact the conductive vs non-conductive regions, and consequently the interrelation between transport and stability. Driven by the need to achieve higher conductivities without disrupting the crystallinity, various pendant-chain chemistries have been developed. In this talk, we will report the results of a systematic investigation on hydration, conductivity, mechanical properties and crystallinity of various types and EWs of PFSA ionomers to (i) develop a structure/property map, and (ii) identify the key parameters controlling morphology and properties. It will be discussed how the pendant-chain and backbone lengths affect the conductivity and crystallinity, respectively. Lastly, the data set will be analyzed to explore universal structure/property relationships for PFSAs.
Use of a rotating cylinder to induce laminar and turbulent separation over a flat plate
NASA Astrophysics Data System (ADS)
Afroz, F.; Lang, A.; Jones, E.
2017-06-01
An innovative and easy technique using a rotating cylinder system has been implemented in a water tunnel experiment to generate an adverse pressure gradient (APG). The strength of the APG was varied through adjustment in the rotation speed and location of the cylinder. Then the technique was used for inducing a laminar separation bubble (LSB) and turbulent boundary layer (TBL) separation over a flat plate. A theoretical model to predict the pressure variation induced on the plate consists of an inviscid flow over a reverse doublet-like configuration of two counter rotating cylinders. This model quantified the pressure distribution with changes of cylinder speed and location. The dimensionless velocity ratio (VR) of the cylinder rotation rate to the mainstream velocity and gap to diameter ratio \\tfrac{G}{D} were chosen as the two main ways of varying the strength of the APG, which affects the nature and extent of the LSB as well as TBL separation. The experimental parametric study, using time-resolved digital particle image velocimetry, was then conducted in a water tunnel. The variation in height (h), length (l), and the separation point (S) of the LSB was documented due to the variation in the APG. The similar type of experimental parametric study was used to explore the unsteady, turbulent separation bubble in a 2D plane aligned with the flow and perpendicular to the plate. The mean detachment locations of TBL separation are determined by two different definitions: (i) back-flow coefficient (χ) = 50%, and (ii) location of start of negative mean skin friction coefficient (C f). They are in good agreement and separation bubble characteristics agreed well with results obtained using different methods thus proving the validity of the technique.
Wang, Chong-Qing; Wang, Hui; Huang, Luo-Luo
2017-07-01
A novel process was proposed for separation of ternary waste plastics by froth flotation. Pretreatment of plastics with potassium permanganate (KMnO 4 ) solution was conducted to aid flotation separation of polycarbonate (PC), polyvinyl chloride (PVC) and polymethyl methacrylate (PMMA) plastics. The effect of pretreatment parameters including KMnO 4 concentration, treatment time, temperature and stirring rate on flotation recovery were investigated by single factor experiments. Surface treatment with KMnO 4 changes selectively the flotation behavior of PC, PVC and PMMA, enabling separation of the plastics by froth flotation. Mechanism of surface treatment was studied by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray photoelectron spectrum (XPS). Effect of frother concentration and flotation time on flotation behavior of plastic mixtures was further studied for flotation separation. The optimized conditions for separation of PC are KMnO 4 concentration 2mmolL -1 , treatment time 10min, temperature 60°C, stirring rate 300rpm, flotation time 1min and frother concentration 17.5mgL -1 . Under optimum conditions, PVC and PMMA mixtures are also separated efficiently by froth flotation associated with KMnO 4 treatment. The purity of PC, PVC and PMMA is up to 100%, 98.41% and 98.68%, while the recovery reaches 96.82%, 98.71% and 98.38%, respectively. Economic analysis manifests remarkable profits of the developed process. Reusing KMnO 4 solution is feasible, enabling the process greener. Copyright © 2017 Elsevier Ltd. All rights reserved.
Jauchem, James R; Cerna, Cesario Z; Lim, Tiffany Y; Seaman, Ronald L
2014-12-01
In an earlier study, we found significant changes in red-blood-cell, leukocyte, and platelet counts, and in red-blood-cell membrane proteins, following exposures of anesthetized pigs to a conducted electrical weapon. In the current study, we examined potential changes in plasma proteins [analyzed via two-dimensional gel electrophoresis (2-DGE)] following two 30 s exposures of anesthetized pigs (Sus scrofa) to a TASER (®) C2 conducted electrical weapon. Patterns of proteins, separated by 2-DGE, were consistent and reproducible between animals and between times of sampling. We determined that the blood plasma collection, handling, storage, and processing techniques we used are suitable for swine blood. There were no statistically significant changes in plasma proteins following the conducted-electrical-weapon exposures. Overall gel patterns of fibrinogen were similar to results of other studies of both pigs and humans (in control settings, not exposed to conducted electrical weapons). The lack of significant changes in plasma proteins may be added to the body of evidence regarding relative safety of TASER C2 device exposures.
2012-10-01
critically ill patients using artificial neural network synthesised by genetic algorithm,” The Lancet, vol. 347, (no. 9009), pp. 1146-1150, 1996...criterion (Table 2). Statistical Analysis Annual progress report page 46 Data synthesis was conducted according to the study design separately as... synthesis of results across included studies was not performed in the study by Detterbeck and Gibson4 which was undertaken in our study. Another unique
Disk Susceptibility Studies with Cefazolin and Cephalothin
Actor, Paul; Guarini, Joseph; Uri, Joseph; Dickson, Judith; Pauls, John F.; Weisbach, Jerry A.
1974-01-01
Cefazolin and cephalothin disk susceptibility and minimal inhibitory concentration determinations were conducted on 591 clinical isolates. Cefazolin demonstrated superior activity, as shown by lower minimal inhibitory concentrations, and a greater percentage of isolates inhibited in the disk susceptibility test. The cephalothin antibiotic class disk by the standard Bauer-Kirby method failed to detect susceptibility to cefazolin in a significant percentage of Escherchia coli, Enterobacter species, and Enterococcus isolates. A separate cefazolin disk with a susceptibility cut-off point of 18 mm is recommended. An alternative to a separate cefazolin disk would be a reinterpretation of the cephalothin susceptibility disk zone diameters so that it would more adequately predict cefazolin activity. PMID:4840450
Potential flow analysis of glaze ice accretions on an airfoil
NASA Technical Reports Server (NTRS)
Zaguli, R. J.
1984-01-01
The results of an analytical/experimental study of the flow fields about an airfoil with leading edge glaze ice accretion shapes are presented. Tests were conducted in the Icing Research Tunnel to measure surface pressure distributions and boundary layer separation reattachment characteristics on a general aviation wing section to which was affixed wooden ice shapes which approximated typical glaze ice accretions. Comparisons were made with predicted pressure distributions using current airfoil analysis codes as well as the Bristow mixed analysis/design airfoil panel code. The Bristow code was also used to predict the separation reattachment dividing streamline by inputting the appropriate experimental surface pressure distribution.
A computational study of incipient leading-edge separation on a 65-deg delta wing at M = 1.60
NASA Technical Reports Server (NTRS)
Mcmillin, S. Naomi; Pittman, James L.; Thomas, James L.
1990-01-01
A computational study on a 65-deg delta wing at a freestream Mach number of 1.60 has been conducted by obtaining conical Reynolds-averaged Navier-Stokes solutions on a parametric series of geometries which varied in leading-edge radius and/or circular-arc camber. The computational results showed that increasing leading-edge radius or camber can delay the onset of leading-edge separation on the leeside of a delta wing at a specific angle of attack. Reynolds number was varied from 1 x 10 to the 6th to 5 x 10 to the 6th for a turbulent boundary-layer and was shown to have a minor effect on the effectiveness of leading-edge radius and/or camber in delaying the onset of leading-edge separation. Both laminar and turbulent boundary-layer models were investigated at a Reynolds number of 1 x 10 to the 6th, and the predicted flow pattern was found to change from attached flow for the turbulent boundary-layer model to separated flow for the laminar boundary-layer model. Based upon these results, three wind-tunnel models have been designed to be tested in the Langley Unitary Plan Wind Tunnel.
Size exclusion chromatography with superficially porous particles.
Schure, Mark R; Moran, Robert E
2017-01-13
A comparison is made using size-exclusion chromatography (SEC) of synthetic polymers between fully porous particles (FPPs) and superficially porous particles (SPPs) with similar particle diameters, pore sizes and equal flow rates. Polystyrene molecular weight standards with a mobile phase of tetrahydrofuran are utilized for all measurements conducted with standard HPLC equipment. Although it is traditionally thought that larger pore volume is thermodynamically advantageous in SEC for better separations, SPPs have kinetic advantages and these will be shown to compensate for the loss in pore volume compared to FPPs. The comparison metrics include the elution range (smaller with SPPs), the plate count (larger for SPPs), the rate production of theoretical plates (larger for SPPs) and the specific resolution (larger with FPPs). Advantages to using SPPs for SEC are discussed such that similar separations can be conducted faster using SPPs. SEC using SPPs offers similar peak capacities to that using FPPs but with faster operation. This also suggests that SEC conducted in the second dimension of a two-dimensional liquid chromatograph may benefit with reduced run time and with equivalently reduced peak width making SPPs advantageous for sampling the first dimension by the second dimension separator. Additional advantages are discussed for biomolecules along with a discussion of optimization criteria for size-based separations. Copyright © 2016 Elsevier B.V. All rights reserved.
Wu, D.; Zhao, L. -D.; Tong, X.; ...
2015-05-19
Lead chalcogenides have exhibited their irreplaceable role as thermoelectric materials at the medium temperature range, owing to highly degenerate electronic bands and intrinsically low thermal conductivities. PbTe-PbS pseudo-binary has been paid extensive attentions due to the even lower thermal conductivity which originates largely from the coexistence of both alloying and phase-separated precipitations. To investigate the competition between alloying and phase separation and its pronounced effect on the thermoelectric performance in PbTe-PbS, we systematically studied Spark Plasma Sintered (SPSed), 3 at% Na- doped (PbTe) 1-x(PbS)x samples with x=10%, 15%, 20%, 25%, 30% and 35% by means of transmission electron microscopy (TEM)more » observations and theoretical calculations. Corresponding to the lowest lattice thermal conductivity as a result of the balance between point defect- and precipitates- scattering, the highest figure of merit ZT~2.3 was obtained at 923 K when PbS phase fraction x is at 20%. The consistently lower lattice thermal conductivities in SPSed samples compared with corresponding ingots, resulting from the powdering and follow-up consolidation processes, also contribute to the observed superior ZT. Notably, the onset of carrier concentration modulation ~600 K due to excessive Na’s diffusion and re-dissolution leads to the observed saturations of electrical transport properties, which is believed equally crucial to the outstanding thermoelectric performance of SPSed PbTe-PbS samples.« less
Apker Award Recipient: Renormalization-Group Study of Helium Mixtures Immersed in a Porous Medium
NASA Astrophysics Data System (ADS)
Lopatnikova, Anna
1998-03-01
Superfluidity and phase separation in ^3He-^4He mixtures immersed in aerogel are studied by renormalization-group theory. Firstly, the theory is applied to jungle-gym (non-random) aerogel.(A. Lopatnikova and A.N. Berker, Phys. Rev. B 55, 3798 (1997).) This calculation is conducted via the coupled renormalization-group mappings of interactions near and away from aerogel. Superfluidity at very low ^4He concentrations and a depressed tricritical temperature are found at the onset of superfludity. A superfluid-superfluid phase separation, terminating at an isolated critical point, is found entirely within the superfluid phase. Secondly, the theory is applied to true aerogel, which has quenched disorder at both atomic and geometric levels.(A. Lopatnikova and A.N. Berker, Phys. Rev. B 56, 11865 (1997).) This calculation is conducted via the coupled renormalization-group mappings, near and away from aerogel, of quenched probability distributions of random interactions. Random-bond effects on superfluidity onset and random-field effects on superfluid phase separation are seen. The quenched randomness causes the λ line of second-order phase transitions of superfluidity onset to reach zero temperature, in agreement with general prediction and experiments. Based on these studies, the experimentally observed(S.B. Kim, J. Ma, and M.H.W. Chan, Phys. Rev. Lett. 71, 2268 (1993); N. Mulders and M.H.W. Chan, Phys. Rev. Lett. 75, 3705 (1995).) distinctive characteristics of ^3He-^4He mixtures in aerogel are related to the aerogel properties of connectivity, tenuousness, and atomic and geometric randomness.
Electrochromic optical switching device
Lampert, C.M.; Visco, S.J.
1992-08-25
An electrochromic cell is disclosed which comprises an electrochromic layer, a polymerizable organo-sulfur layer which comprises the counter electrode of the structure, and an ionically conductive electronically insulating material which comprises the separator between the electrodes. In a preferred embodiment, both the separator and the organo-sulfur electrode (in both its charged and uncharged states) are transparent either to visible light or to the entire solar spectrum. An electrochromic device is disclosed which comprises such electrodes and separator encased in glass plates on the inner surface of each of which is formed a transparent electrically conductive film in respective electrical contact with the electrodes which facilitates formation of an external electrical connection or contact to the electrodes of the device to permit electrical connection of the device to an external potential source. 3 figs.
Fluorine lubricated bearing technology
NASA Technical Reports Server (NTRS)
Mallaire, F. R.
1973-01-01
An experimental program was conducted to evaluate and select materials for ball bearings intended for use in liquid fluorine and/or FLOX. The ability of three different ball-separator materials, each containing nickel, to form and transfer a nickel fluoride film to provide effective lubrication at the required areas of a ball bearing operating in liquid fluorine was evaluated. In addition, solid lubrication of a ball bearing operating in liquid fluorine by either a fused fluoride coating applied to all surfaces of the ball separator or by a fluoride impregnation of porous sintered material ball separators was evaluated. Less bearing wear occurred when tests were conducted in the less reactive FLOX. Bearings fabricated from any of the materials tested would have relatively short wear lives and would require frequent replacement in a reusable engine.
Electrochromic optical switching device
Lampert, Carl M.; Visco, Steven J.
1992-01-01
An electrochromic cell is disclosed which comprises an electrochromic layer, a polymerizable organo-sulfur layer which comprises the counter electrode of the structure, and an ionically conductive electronically insulating material which comprises the separator between the electrodes. In a preferred embodiment, both the separator and the organo-sulfur electrode (in both its charged and uncharged states) are transparent either to visible light or to the entire solar spectrum. An electrochromic device is disclosed which comprises such electrodes and separator encased in glass plates on the inner surface of each of which is formed a transparent electrically conductive film in respective electrical contact with the electrodes which facilitates formation of an external electrical connection or contact to the electrodes of the device to permit electrical connection of the device to an external potential source.
NASA Astrophysics Data System (ADS)
Wiedigen, S.; Kramer, T.; Feuchter, M.; Knorr, I.; Nee, N.; Hoffmann, J.; Kamlah, M.; Volkert, C. A.; Jooss, Ch.
2012-02-01
Separating out effects of point defects and lattice strain on thermal conductivity is essential for improvement of thermoelectric properties of SrTiO3. We study relations between defects generated during deposition, induced lattice strain, and their impact on thermal conductivity κ in homoepitaxial SrTiO3 films prepared by ion-beam sputtering. Lowering the deposition temperature gives rise to lattice expansion by enhancement of point defect density which increases the hardness of the films. Due to a fully coherent substrate-film interface, the lattice misfit induces a large biaxial strain. However, we can show that the temperature dependence of κ is mainly sensitive on the defect concentration.
USDA-ARS?s Scientific Manuscript database
Water quality issues continue to vex agriculture. Understanding contaminant-specific pathways could help clarify effective water quality management strategies in watersheds. Hypothesis: If conducted at nested scales, hydrograph separation techniques can identify contaminant-specific pathways that co...
SITE TECHNOLOGY CAPSULE: ROCHEM SEPARATION SYSTEMS, INC. - DISC TUBE MODULE TECHNOLOGY
SITE Program demonstration of the Rochem Disc Tube Module™(DTM) developed by Rochem Separations Systems, Inc. The demonstration test was conducted at the central landfill superfund site in Johnston, Rhode island in August, 1994. The DTM technology is an innovative membrane filt...
Exploring the Lack of a Disfluency Effect: Evidence from Eye Movements
ERIC Educational Resources Information Center
Strukelj, Alexander; Scheiter, Katharina; Nyström, Marcus; Holmqvist, Kenneth
2016-01-01
An eye-tracking study with 60 native Swedish speakers (18-30 years) was conducted to investigate the positive effects on learning outcomes predicted by the disfluency effect. Subtle low-pass filtering was used as a disfluency manipulation and compared with a control condition using regular text. The text was presented on four separate text…
ERIC Educational Resources Information Center
Valdimarsdottir, Hildur; Halldorsdottir, Lilja Yr; Sigurdardottir, Zuilma Gabriela
2010-01-01
A multiple baseline across settings was used to evaluate the effects of differential reinforcement of alternative behavior, nonremoval of the fork (Hoch, Babbitt, Coe, Krell, & Hackbert, 1994), and stimulus fading on consumption of food rejected previously. The study was conducted in two separate settings, and caregivers were trained in the…
ERIC Educational Resources Information Center
Smith, Derrick W.; Smothers, Sinikka M.
2012-01-01
Introduction: The purpose of the study presented here was to determine how well tactile graphics (specifically data analysis graphs) in secondary mathematics and science braille textbooks correlated with the print graphics. Method: A content analysis was conducted on 598 separate data analysis graphics from 10 mathematics and science textbooks.…
USDA-ARS?s Scientific Manuscript database
Water use efficiency (WUE) was determined for two separate blackberry cultural management studies conducted during the years 2006-2008 (Expt. 1) and 2008-2010 (Expt. 2) in a semi-arid subtropical area in south Texas (Lat. 26° N). Adjustments were made for natural precipitation and total season wate...
An Analysis of High School Home Economics Students Attitudes in Different Geosocial Environments.
ERIC Educational Resources Information Center
Erickson, Patricia M.
Teachers, especially home economics teachers, would be better prepared to evaluate subject matter and to separate fact and personal opinion if they had a better understanding of diverse student backgrounds. To find out such background information, a study was conducted to analyze attitudes and values held by junior and senior students in home…
Consumer Perspectives on Involving Family and Significant Others in a Healthy Lifestyle Intervention
ERIC Educational Resources Information Center
Aschbrenner, Kelly; Bartels, Stephen; Mueser, Kim; Carpenter-Song, Elizabeth; Kinney, Allison
2012-01-01
This focus group study explored the potential benefits and challenges of involving family members and significant others in a healthy lifestyle program for people with serious mental illness (SMI). Six focus group interviews were conducted with a total of 30 people with SMI, who were participants in a healthy lifestyle intervention. Separate focus…
A Comparison of Guided Assignments and NAEP Format Tests on Adolescent Response to Literature.
ERIC Educational Resources Information Center
Appleman, Deborah
This study investigated the effects of heuristically based assignments and tests on adolescents' written responses to literature. In order to examine both tests and instruction, two separate but related experiments were conducted. Experiment 1 investigated whether the inclusion of guided prewriting on essay tests for two poems and two short…
Executive Function Mechanisms of Theory of Mind
ERIC Educational Resources Information Center
Ahmed, Fayeza S.; Miller, L. Stephen
2011-01-01
This study examined the relationship between Executive Function (EF) and Theory of Mind (ToM) using the Delis-Kaplan Executive Function System (D-KEFS) and three tests of ToM (Reading the Mind in the Eyes test (RMET), Strange Stories test, and Faux Pas test). Separate regression analyses were conducted, and EF predictors varied by ToM test. No EF…
A Survey of Speech Education in United States Two-Year Colleges.
ERIC Educational Resources Information Center
Planck, Carolyn Roberts
The status of speech education in all United States two-year colleges is discussed. Both public and private schools are examined. Two separate studies were conducted, each utilizing the same procedure. The specific aspects with which the research was concerned were: (1) availability of speech courses, (2) departmentalization of speech courses, (3)…
ERIC Educational Resources Information Center
Kieffer, Kevin M.; Schinka, John A.; Curtiss, Glenn
2004-01-01
This study examined the contributions of the 5-Factor Model (FFM; P. T. Costa & R. R. McCrae, 1992) and RIASEC (J. L. Holland, 1994) constructs of consistency, differentiation, and person-environment congruence in predicting job performance ratings in a large sample (N = 514) of employees. Hierarchical regression analyses conducted separately by…
ERIC Educational Resources Information Center
Davis, Joel J.
1999-01-01
Explores the communicative effectiveness of imprecise frequency descriptors within the context of consumer prescription drug advertising. Conducts two separate studies using a total sample of 147 adults. Finds that consumers are unable to accurately estimate the relative likelihood of side effect occurrence when a list of side effects are preceded…
Who Teaches Information Literacy Competencies? Report of a Study of Faculty
ERIC Educational Resources Information Center
Weiner, Sharon A.
2014-01-01
Information literacy is recognized as an essential competency for educational success. It relates to all disciplines but is not a separate discipline, so it is not clear who takes responsibility for teaching this competency to undergraduates. This is a report of a survey conducted to better understand the extent to which teaching information…
Chemical analysis and quantitation of the tapetum lucidum
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gee, N.A.; Fisher, G.L.; Nash, C.P.
1975-06-01
A study was conducted to provide a basis for the evaluation of the biochemical nature of the $sup 226$Ra alterations of the beagle tapetum. Results indicated that zinc and/or melanin determinations in the tapetum nigrum and tapetum lucidum may allow quantitation of tapetum lucidum tissue without the need for physical separation of the tapetal layers. (HLW)
ERIC Educational Resources Information Center
Higher Education Funding Council for England, Bristol.
This study was conducted to map the range of research-related links between charities and higher education institutions (HEIs) and to make recommendations on how these links could be developed to the mutual advantage of both sectors. The research methods used for the review are described in an associated mapping report, published separately.…
ERIC Educational Resources Information Center
Xu, Yonghong Jade
2017-01-01
Data from a national survey are used to examine how individual characteristics and social structural factors may influence college graduates choosing an occupation that is congruent with their undergraduate field of study. Analysis is conducted separately for males and females and for students in science, technology, engineering, and mathematics…
ERIC Educational Resources Information Center
Tefera, Adai; Voulgarides, Catherine Kramarczuk
2016-01-01
To understand the challenges associated with the enactment of educational policies that aim to improve equity and opportunity for students of color with disabilities, this chapter focuses on two separately conducted ethnographic studies. The first investigates district administrators' approaches to addressing racial disproportionality after the…
Composite separators and redox flow batteries based on porous separators
Li, Bin; Wei, Xiaoliang; Luo, Qingtao; Nie, Zimin; Wang, Wei; Sprenkle, Vincent L.
2016-01-12
Composite separators having a porous structure and including acid-stable, hydrophilic, inorganic particles enmeshed in a substantially fully fluorinated polyolefin matrix can be utilized in a number of applications. The inorganic particles can provide hydrophilic characteristics. The pores of the separator result in good selectivity and electrical conductivity. The fluorinated polymeric backbone can result in high chemical stability. Accordingly, one application of the composite separators is in redox flow batteries as low cost membranes. In such applications, the composite separator can also enable additional property-enhancing features compared to ion-exchange membranes. For example, simple capacity control can be achieved through hydraulic pressure by balancing the volumes of electrolyte on each side of the separator. While a porous separator can also allow for volume and pressure regulation, in RFBs that utilize corrosive and/or oxidizing compounds, the composite separators described herein are preferable for their robustness in the presence of such compounds.
The Effect of 7E Model on Conceptual Success of Students in the Unit of Electromagnetism
ERIC Educational Resources Information Center
Turgut, Umit; Colak, Alp; Salar, Riza
2016-01-01
The aim of this study was to investigate the impact of the course materials developed in accordance with 7E model in the unit of electromagnetism in high school physics class on students' conceptual success. The present study was conducted with a total of 52 11th grade students in two separate classrooms at a high school. The action research…
Park, Sang-In; Lee, Howard; Oh, Jaeseong; Lim, Kyoung Soo; Jang, In-Jin; Kim, Jeong-Ae; Jung, Jong Hyuk; Yu, Kyung-Sang
2015-01-01
In type 2 diabetes mellitus, fixed-dose combination (FDC) can provide the complementary benefits of correction of multiple pathophysiologic defects such as dysfunctions in glycemic or metabolic control while improving compliance compared with separate tablets taken together. The objective of the study reported here was to compare the pharmacodynamic (PD), pharmacokinetic (PK), and tolerability profiles of gemigliptin and extended-release metformin (metformin XR) between FDC and separate tablets. A randomized, open-label, single-dose, two-way, two-period, crossover study was conducted in 28 healthy male volunteers. Two FDC tablets of gemigliptin/metformin 25/500 mg or separate tablets of gemigliptin (50 mg ×1) and metformin XR (500 mg ×2) were orally administered in each period. Serial blood samples were collected up to 48 hours post-dose to determine dipeptidyl peptidase 4 (DPP-4) activity using spectrophotometric assay and concentrations of gemigliptin and metformin using tandem mass spectrometry. Geometric mean ratios (GMRs) of FDC to separate tablet formulations and their 90% confidence intervals (CIs) were calculated to compare the PD and PK parameters between the two formulations. Tolerability was assessed throughout the study. The plasma DPP-4 activity-time curves of the FDC and the separate tablets almost overlapped, leading to a GMR (90% CI) of the FDC to separate tablets for the plasma DPP-4 activity and its maximum inhibition of 1.00 (0.97-1.04) and 0.92 (0.82-1.05), respectively. Likewise, all of the GMRs (90% CIs) of FDC to separate tablets for the area under the plasma concentration-time curve and maximum plasma concentration of gemigliptin and metformin fell entirely within the conventional bioequivalence range of 0.80-1.25. Both the FDC and separate tablets were well tolerated. The PD, PK, and tolerability profiles of gemigliptin and metformin XR in FDC and separate tablets were found to be comparable. The FDC tablet of gemigliptin and metformin sustained release can be a convenient therapeutic option in patients with type 2 diabetes mellitus requiring a combination approach.
Cochlear pathology in chronic suppurative otitis media.
Walby, A P; Barrera, A; Schuknecht, H F
1983-01-01
Chronic suppurative otitis media (COM) is reported to cause elevation of bone-conduction thresholds either by damage to cochlear sensorineural structures or by alteration in the mechanics of sound transmission in the ear. A retrospective study was made of the medical records of 87 patients with unilateral uncomplicated COM to document that abnormality in bone conduction does exist. In a separate study the cochlear pathology in 12 pairs of temporal bones with unilateral COM was studied by light microscopy. Infected ears showed higher than normal mean bone-conduction thresholds by amounts ranging from 1 dB at 500 Hz to 9.5 dB at 4,000 Hz. The temporal bones showed no greater loss of specialized sensorineural structures in infected ears than in normal control ears. Because there is no evidence that COM caused destruction of hair cells or cochlear neurons, alteration in the mechanics of sound transmission becomes a more plausible explanation for the hearing losses.
Single Wall Nanotube Type-Specific Functionalization and Separation
NASA Technical Reports Server (NTRS)
Boul, Peter; Nikolaev, Pavel; Sosa, Edward; Arepalli, Sivaram; Yowell, Leonard
2008-01-01
Metallic single-wall carbon nanotubes were selectively solubilized in THF and separated from semiconducting nanotubes. Once separated, the functionalized metallic tubes were de-functionalized to restore their metallic band structure. Absorption and Raman spectroscopy of the enriched samples support conclusions of the enrichment of nanotube samples by metallic type. A scalable method for enriching nanotube conductive type has been developed. Raman and UV-Vis data indicate SWCNT reaction with dodecylbenzenediazonium results in metallic enrichment. It is expected that further refinement of this techniques will lead to more dramatic separations of types and diameters.
Khanna, Rajesh; Handa, Aashish; Virk, Rupam Kaur; Ghai, Deepika; Handa, Rajni Sharma; Goel, Asim
2017-01-01
The process of cleaning and shaping the canal is not an easy goal to obtain, as canal curvature played a significant role during the instrumentation of the curved canals. The present in vivo study was conducted to evaluate procedural errors during the preparation of curved root canals using hand Nitiflex and rotary K3XF instruments. Procedural errors such as ledge formation, instrument separation, and perforation (apical, furcal, strip) were determined in sixty patients, divided into two groups. In Group I, thirty teeth in thirty patients were prepared using hand Nitiflex system, and in Group II, thirty teeth in thirty patients were prepared using K3XF rotary system. The evaluation was done clinically as well as radiographically. The results recorded from both groups were compiled and put to statistical analysis. Chi-square test was used to compare the procedural errors (instrument separation, ledge formation, and perforation). In the present study, both hand Nitiflex and rotary K3XF showed ledge formation and instrument separation. Although ledge formation and instrument separation by rotary K3XF file system was less as compared to hand Nitiflex. No perforation was seen in both the instrument groups. Canal curvature played a significant role during the instrumentation of the curved canals. Procedural errors such as ledge formation and instrument separation by rotary K3XF file system were less as compared to hand Nitiflex.
Khanna, Rajesh; Handa, Aashish; Virk, Rupam Kaur; Ghai, Deepika; Handa, Rajni Sharma; Goel, Asim
2017-01-01
Background: The process of cleaning and shaping the canal is not an easy goal to obtain, as canal curvature played a significant role during the instrumentation of the curved canals. Aim: The present in vivo study was conducted to evaluate procedural errors during the preparation of curved root canals using hand Nitiflex and rotary K3XF instruments. Materials and Methods: Procedural errors such as ledge formation, instrument separation, and perforation (apical, furcal, strip) were determined in sixty patients, divided into two groups. In Group I, thirty teeth in thirty patients were prepared using hand Nitiflex system, and in Group II, thirty teeth in thirty patients were prepared using K3XF rotary system. The evaluation was done clinically as well as radiographically. The results recorded from both groups were compiled and put to statistical analysis. Statistical Analysis: Chi-square test was used to compare the procedural errors (instrument separation, ledge formation, and perforation). Results: In the present study, both hand Nitiflex and rotary K3XF showed ledge formation and instrument separation. Although ledge formation and instrument separation by rotary K3XF file system was less as compared to hand Nitiflex. No perforation was seen in both the instrument groups. Conclusion: Canal curvature played a significant role during the instrumentation of the curved canals. Procedural errors such as ledge formation and instrument separation by rotary K3XF file system were less as compared to hand Nitiflex. PMID:29042727
Li, Shelly X; Jue, Jan-fong; Herbst, Ronald Scott; Herrmann, Steven Douglas
2015-01-13
An apparatus for the real-time, in-situ monitoring of actinide-ion concentrations. A working electrolyte is positioned within the interior of a container. The working electrolyte is separated from a reference electrolyte by a separator. A working electrode is at least partially in contact with the working electrolyte. A reference electrode is at least partially in contact with the reference electrolyte. A voltmeter is electrically connected to the working electrode and the reference electrode. The working electrolyte comprises an actinide-ion of interest. The separator is ionically conductive to the actinide-ion of interest. The separator comprises an actinide, Zr, and Nb. Preferably, the actinide of the separator is Am or Np, more preferably Pu. In one embodiment, the actinide of the separator is the actinide of interest. In another embodiment, the separator further comprises P and O.
Astrup, Aske; Pedersen, Carsten B; Mok, Pearl L H; Carr, Matthew J; Webb, Roger T
2017-01-15
Experience of child-parent separation predicts adverse outcomes in later life. We conducted a detailed epidemiological examination of this complex relationship by modelling an array of separation scenarios and trajectories and subsequent risk of self-harm. This cohort study examined persons born in Denmark during 1971-1997. We measured child-parent separations each year from birth to 15th birthday via complete residential address records in the Civil Registration System. Self-harm episodes between 15th birthday and early middle age were ascertained through linkage to psychiatric and general hospital registers. Incidence rate ratios (IRRs) from Poisson regression models were estimated against a reference category of individuals not separated from their parents. All exposure models examined indicated an association with raised self-harm risk. For example, large elevations in risk were observed in relation to separation from both parents at 15th birthday (IRR 5.50, 95% CI 5.25-5.77), experiencing five or more changes in child-parent separation status (IRR 5.24, CI 4.88-5.63), and having a shorter duration of familial cohesion during upbringing. There was no significant evidence for varying strength of association according to child's gender. Measuring child-parent separation according to differential residential addresses took no account of the reason for or circumstances of these separations. These novel findings suggest that self-harm prevention initiatives should be tailored toward exposed persons who remain psychologically distressed into adulthood. These high-risk subgroups include individuals with little experience of familial cohesion during their upbringing, those with the most complicated trajectories who lived through multiple child-parent separation transitions, and those separated from both parents during early adolescence. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Using resolvent analysis for the design of separation control on a NACA 0012 airfoil
NASA Astrophysics Data System (ADS)
Yeh, Chi-An; Taira, Kunihiko
2017-11-01
A combined effort based on large-eddy simulation and resolvent analysis on the separated flow over a NACA 0012 airfoil is conducted to design active flow control for suppression of separation. This study considers the the airfoil at 6 deg. angle-of-attack and Reynolds number of 23000. The response mode obtained from the resolvent analysis about the baseline turbulent mean flow reveals modal structures that can be categorized into three families when sweeping through the resonant frequency: (1) von Karman wake structure for low frequency; (2) Kelvin-Helmholtz structure in the separation bubble for high frequency; (3) blended structure of (1) and (2) for the intermediate frequency. Leveraging the insights from resolvent analysis, unsteady thermal actuation is introduced to the flow near the leading-edge to examine the use of the frequencies from three families for separation control in LES. As indicated by the resolvent response modes, we find that the use of intermediate frequencies are most effective in suppressing the flow separation, since the shear layer over the separation bubble and the wake are both receptive to the perturbation at the these frequencies. The resolvent-analysis-based control strategy achieves 35% drag reduction and 9% lift increase with effective frequency. This work was supported by Office of Naval Research (N00014-15-R-FO13) and Army Research Office (W911NF-14-1-0224).
Low speed streak formation in a separating turbulent boundary layer
NASA Astrophysics Data System (ADS)
Santos, Leonardo; Lang, Amy; Wahidi, Redha; Bonacci, Andrew
2017-11-01
Separation control mechanisms present on the skin of the shortfin mako shark may permit higher swimming speeds. The morphology of the scales varies over the entire body, with maximum scale flexibility found on the flank region with an adverse pressure gradient(APG). It is hypothesized that reversing flow close the skin bristles the scales inhibiting further flow reversal and controlling flow separation. Experiments are conducted in water tunnel facility and the flow field of a separating turbulent boundary layer(TBL) is measured using DPIV and Insight V3V. Flow separation is induced by a rotating cylinder which generates a controlled APG over a flat plate (Re = 510000 and 620000). Specifically, the low speed streak(LSS) formation is documented and matches predicted sizing based on viscous length scale calculations. It is surmised that shark scale width corresponds to this LSS sizing for real swimming TBL conditions. However, flow separation control has been demonstrated over real skin specimens under much lower speed conditions which indicates the mechanism is fairly Re independent if multiple scales are bristled as the width of the LSS increases. The formation of reversing flow within the streaks is studied specifically to better understand the process by which this flow initiates scale bristling on shortfin mako skin as a passive, flow actuated separation control mechanism. The authors would like to greatefully acknowledge the Army Research Office for funding this project.
Carnes, Stephanie; O'Brien, Stacey; Szewczak, Angelica; Tremeau-Cayel, Lauriane; Rowe, Walter F; McCord, Bruce; Lurie, Ira S
2017-09-01
A comparison of ultra high performance supercritical fluid chromatography, ultra high performance liquid chromatography, and gas chromatography for the separation of synthetic cathinones has been conducted. Nine different mixtures of bath salts were analyzed in this study. The three different chromatographic techniques were examined using a general set of controlled synthetic cathinones as well as a variety of other synthetic cathinones that exist as positional isomers. Overall 35 different synthetic cathinones were analyzed. A variety of column types and chromatographic modes were examined for developing each separation. For the ultra high performance supercritical fluid chromatography separations, analyses were performed using a series of Torus and Trefoil columns with either ammonium formate or ammonium hydroxide as additives, and methanol, ethanol or isopropanol organic solvents as modifiers. Ultra high performance liquid chromatographic separations were performed in both reversed phase and hydrophilic interaction chromatographic modes using SPP C18 and SPP HILIC columns. Gas chromatography separations were performed using an Elite-5MS capillary column. The orthogonality of ultra high performance supercritical fluid chromatography, ultra high performance liquid chromatography, and gas chromatography was examined using principal component analysis. For the best overall separation of synthetic cathinones, the use of ultra high performance supercritical fluid chromatography in combination with gas chromatography is recommended. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Ndejjo, Rawlance; Musoke, David; Musinguzi, Geofrey; Halage, Abdullah Ali; Carpenter, David O.; Ssempebwa, John C.
2016-01-01
Poor solid waste management is among the major challenges facing urban slums in developing countries including Uganda. Understanding community concerns and willingness towards involvement in solid waste management improvement initiatives is critical for informing interventions in slums. Methods. We used a cross-sectional study to collect quantitative data from 435 residents in two urban slums in central Uganda. A semistructured questionnaire was used which assessed waste collection practices, separation and disposal methods, concerns regarding solid wastes, and willingness to participate in waste separation and composting. Data was analysed using STATA 12. Results. Food remains (38%) and plastics (37%) formed the biggest proportion of wastes generated in households. Most households (35.9%) disposed of general wastes by open dumping while 27% disposed of plastics by burning. Only 8.8% of households conducted composting while 55% carried out separation for some decomposable wastes. Separation was carried out for only banana peelings and leftover foods for feeding animals. Respondents expressed high willingness to separate (76.6%) and compost (54.9%) solid wastes. Conclusion. Practices in waste disposal and separation were poor despite high willingness to participate in initiatives to improve waste management, highlighting a need for authorities to engage residents of slums to improve their practices. PMID:27066081
Mukama, Trasias; Ndejjo, Rawlance; Musoke, David; Musinguzi, Geofrey; Halage, Abdullah Ali; Carpenter, David O; Ssempebwa, John C
2016-01-01
Poor solid waste management is among the major challenges facing urban slums in developing countries including Uganda. Understanding community concerns and willingness towards involvement in solid waste management improvement initiatives is critical for informing interventions in slums. We used a cross-sectional study to collect quantitative data from 435 residents in two urban slums in central Uganda. A semistructured questionnaire was used which assessed waste collection practices, separation and disposal methods, concerns regarding solid wastes, and willingness to participate in waste separation and composting. Data was analysed using STATA 12. Food remains (38%) and plastics (37%) formed the biggest proportion of wastes generated in households. Most households (35.9%) disposed of general wastes by open dumping while 27% disposed of plastics by burning. Only 8.8% of households conducted composting while 55% carried out separation for some decomposable wastes. Separation was carried out for only banana peelings and leftover foods for feeding animals. Respondents expressed high willingness to separate (76.6%) and compost (54.9%) solid wastes. Practices in waste disposal and separation were poor despite high willingness to participate in initiatives to improve waste management, highlighting a need for authorities to engage residents of slums to improve their practices.
Shock unsteadiness in a thrust optimized parabolic nozzle
NASA Astrophysics Data System (ADS)
Verma, S. B.
2009-07-01
This paper discusses the nature of shock unsteadiness, in an overexpanded thrust optimized parabolic nozzle, prevalent in various flow separation modes experienced during start up {(δ P0 /δ t > 0)} and shut down {(δ P0/δ t < 0)} sequences. The results are based on simultaneously acquired data from real-time wall pressure measurements using Kulite pressure transducers, high-speed schlieren (2 kHz) of the exhaust flow-field and from strain-gauges installed on the nozzle bending tube. Shock unsteadiness in the separation region is seen to increase significantly just before the onset of each flow transition, even during steady nozzle operation. The intensity of this measure ( rms level) is seen to be strongly influenced by relative locations of normal and overexpansion shock, the decrease in radial size of re-circulation zone in the back-flow region, and finally, the local nozzle wall contour. During restricted shock separation, the pressure fluctuations in separation region exhibit periodic characteristics rather than the usually observed characteristics of intermittent separation. The possible physical mechanisms responsible for the generation of flow unsteadiness in various separation modes are discussed. The results are from an experimental study conducted in P6.2 cold-gas subscale test facility using a thrust optimized parabolic nozzle of area-ratio 30.
Management of Vortices Trailing Flapped Wings via Separation Control
NASA Technical Reports Server (NTRS)
Greenblatt, David
2005-01-01
A pilot study was conducted on a flapped semi-span model to investigate the concept and viability of near-wake vortex management via separation control. Passive control was achieved by means of a simple fairing and active control was achieved via zero mass-flux blowing slots. Vortex sheet strength, estimated by integrating surface pressure ports, was used to predict vortex characteristics by means of inviscid rollup relations. Furthermore, vortices trailing the flaps were mapped using a seven-hole probe. Separation control was found to have a marked effect on vortex location, strength, tangential velocity, axial velocity and size over a wide range of angles of attack and control conditions. In general, the vortex trends were well predicted by the inviscid rollup relations. Manipulation of the separated flow near the flap edges exerted significant control over both outboard and inboard edge vortices while producing negligible lift excursions. Dynamic separation and attachment control was found to be an effective means for dynamically perturbing the vortex from arbitrarily long wavelengths down to wavelengths less than a typical wingspan. In summary, separation control has the potential for application to time-independent or time-dependent wake alleviation schemes, where the latter can be deployed to minimize adverse effects on ride-quality and dynamic structural loading.
NASA Astrophysics Data System (ADS)
Long, J.; New, T. H.
2016-07-01
Vortical structures and dynamics of a Re h = 2100 elliptic jet impinging upon a flat plate were studied at H/ d h = 1, 2 and 4 jet-to-plate separation distances. Flow investigations were conducted along both its major and minor planes using laser-induced fluorescence and digital particle image velocimetry techniques. Results show that the impingement process along the major plane largely consists of primary jet ring-vortex and wall-separated secondary vortex formations, where they subsequently separate from the flat plate at smaller H/ d h = 1 and 2 separation distances. Key vortex formation locations occur closer to the impingement point as the separation distance increases. Interestingly, braid vortices and rib structures begin to take part in the impingement process at H/ d h = 4 and wave instabilities dominate the flow field. In contrast, significantly more coherent primary and secondary vortices with physically larger vortex core sizes and higher vortex strengths are observed along the minor plane, with no signs of braid vortices and rib structures. Lastly, influences of these different flow dynamics on the major and minor plane instantaneous and mean skin friction coefficient levels are investigated to shed light on the effects of separation distance on the wall shear stress distributions.
SITE program demonstration of the Rochem Disc Tube™ Module (DTM) developed by Rochem Separation systems Inc. The demonstration test was conducted at the central landfill Superfund site in Johnston, Rhode Island in August 1994. The DTM technology is an innovative membrane filtra...
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%. © 2016 Wiley Periodicals, Inc.
High-performance computing-based exploration of flow control with micro devices.
Fujii, Kozo
2014-08-13
The dielectric barrier discharge (DBD) plasma actuator that controls flow separation is one of the promising technologies to realize energy savings and noise reduction of fluid dynamic systems. However, the mechanism for controlling flow separation is not clearly defined, and this lack of knowledge prevents practical use of this technology. Therefore, large-scale computations for the study of the DBD plasma actuator have been conducted using the Japanese Petaflops supercomputer 'K' for three different Reynolds numbers. Numbers of new findings on the control of flow separation by the DBD plasma actuator have been obtained from the simulations, and some of them are presented in this study. Knowledge of suitable device parameters is also obtained. The DBD plasma actuator is clearly shown to be very effective for controlling flow separation at a Reynolds number of around 10(5), and several times larger lift-to-drag ratio can be achieved at higher angles of attack after stall. For higher Reynolds numbers, separated flow is partially controlled. Flow analysis shows key features towards better control. DBD plasma actuators are a promising technology, which could reduce fuel consumption and contribute to a green environment by achieving high aerodynamic performance. The knowledge described above can be obtained only with high-end computers such as the supercomputer 'K'. © 2014 The Author(s) Published by the Royal Society. All rights reserved.
Nanofiber/ZrO2-based mixed matrix separator for high safety/high-rate lithium-ion batteries
NASA Astrophysics Data System (ADS)
Xiao, Wei; Liu, Jianguo; Yan, Chuanwei
2017-10-01
A novel asymmetric separator based on a thin bacterial cellulose nanofiber (BCF)/nano-ZrO2 composite layer and a non-woven support was prepared by paper-making method. Owing to the relatively polar constituents and well-developed, gradient porous structure, the separator exhibited the advantages of higher thermal resistance, electrolyte wettability, and ionic conductivity in comparison to polyethylene separator. Based on these advantages, the Li/LiFePO4 cells assembled from this composite separator showed excellent performance characteristics, including outstanding C-rate capability, high capacity and cycling performance. Production of the composite separator is simple, environmentally benign and economically viable. Therefore, it's a good candidate for creating improved lithium-ion batteries.
A Laterally-Mobile Mixed Polymer/Polyelectrolyte Brush Undergoes a Macroscopic Phase Separation
NASA Astrophysics Data System (ADS)
Lee, Hoyoung; Park, Hae-Woong; Tsouris, Vasilios; Choi, Je; Mustafa, Rafid; Lim, Yunho; Meron, Mati; Lin, Binhua; Won, You-Yeon
2013-03-01
We studied mixed PEO and PDMAEMA brushes. The question we attempted to answer was: When the chain grafting points are laterally mobile, how will this lateral mobility influence the structure and phase behavior of the mixed brush? Two different model mixed PEO/PDMAEMA brush systems were prepared: a mobile mixed brush by spreading a mixture of two diblock copolymers, PEO-PnBA and PDMAEMA-PnBA, onto the air-water interface, and an inseparable mixed brush using a PEO-PnBA-PDMAEMA triblock copolymer having respective brush molecular weights matched to those of the diblock copolymers. These two systems were investigated by surface pressure-area isotherm, X-ray reflectivity and AFM imaging measurements. The results suggest that the mobile mixed brush undergoes a lateral macroscopic phase separation at high chain grafting densities, whereas the inseparable system is only microscopically phase separated under comparable brush density conditions. We also conducted an SCF analysis of the phase behavior of the mixed brush system. This analysis further supported the experimental findings. The macroscopic phase separation observed in the mobile system is in contrast to the microphase separation behavior commonly observed in two-dimensional laterally-mobile small molecule mixtures.
Microdevice for plasma separation from whole human blood using bio-physical and geometrical effects
NASA Astrophysics Data System (ADS)
Tripathi, Siddhartha; Kumar, Y. V. Balavarun; Agrawal, Amit; Prabhakar, Amit; Joshi, Suhas S.
2016-06-01
In this research work, we present a simple and efficient passive microfluidic device for plasma separation from pure blood. The microdevice has been fabricated using conventional photolithography technique on a single layer of polydimethylsiloxane, and has been extensively tested on whole blood and enhanced (upto 62%) hematocrit levels of human blood. The microdevice employs elevated dimensions of about 100 μm such elevated dimensions ensure clog-free operation of the microdevice and is relatively easy to fabricate. We show that our microdevice achieves almost 100% separation efficiency on undiluted blood in the flow rate range of 0.3 to 0.5 ml/min. Detailed biological characterization of the plasma obtained from the microdevice is carried out by testing: proteins by ultra-violet spectrophotometric method, hCG (human chorionic gonadotropin) hormone, and conducting random blood glucose test. Additionally, flow cytometry study has also been carried on the separated plasma. These tests attest to the high quality of plasma recovered. The microdevice developed in this work is an outcome of extensive experimental research on understanding the flow behavior and separation phenomenon of blood in microchannels. The microdevice is compact, economical and effective, and is particularly suited in continuous flow operations.
Tian, Ailin; Qi, Jing; Liu, Yating; Wang, Fengkang; Ito, Yoichiro; Wei, Yun
2013-01-01
Separation of enantiomers still remains a challenge due to their identical physical and chemical properties in a chiral environment, and the research on specific chiral selector along with separation techniques continues to be conducted to resolve individual enantiomers. In our laboratory the promising magnetic chiral microspheres Fe3O4@SiO2@cellulose-2, 3-bis (3, 5-dimethylphenylcarbamate) have been developed to facilitate the resolution using both its magnetic property and chiral recognition ability. In our present studies this magnetic chiral selector was first purified by centrifuge field flow fractionation, and then used to separate benzoin racemate by a chromatographic method. Uniform-sized and masking-impurity-removed magnetic chiral selector was first obtained by field flow fractionation with ethanol through a spiral column mounted on the type-J planetary centrifuge, and using the purified magnetic chiral selector, the final chromatographic separation of benzoin racemate was successfully performed by eluting with ethanol through a coiled tube (wound around the cylindrical magnet to retain the magnetic chiral selector as a stationary phase) submerged in dry ice. In addition, an external magnetic field facilitates the recycling of the magnetic chiral selector. PMID:23891368
Oxygen transport in the Sr{sub 2}Fe{sub 3{minus}x}Co{sub x}O{sub y} system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ma, B.
The mixed-conducting Sr-Fe-Co oxide has potential use as a gas separation membrane. Its superior oxygen transport reveals the feasibility of using oxide membranes in large-scale oxygen separation. Sr{sub 2}Fe{sub 3{minus}x}Co{sub x}O{sub y} (with x = 0.0, 0.3, 0.6, and 1.0) samples were made by solid state reaction. To understand the oxygen transport mechanism in this system, conductivity and thermogravimetry experiments were conducted at high temperature in various oxygen partial pressure environments. The oxygen diffusion coefficient was determined from the time relaxation transient behavior of the specimen after switching the surrounding atmosphere. Mobility of the charge carrier was derived from relativemore » conductivity and weight changes. X-ray diffraction experiments were carried out on these samples to determine their crystal structures.« less
Protonic Conduction of BaCe0.85YO. 1503 Doped with SrTiO3
NASA Technical Reports Server (NTRS)
Dynys, Frederick W.; Sayir, Ali
2005-01-01
Reformers based on ceramic membrane technology potentially offer hydrogen production that is comparable to the cost of fossil fuels. Protonic conducting ceramic with the chemical formula AB03 offers the promise of highly selective hydrogen separation at intermediate temperature (400-800 C). Among different perovskite-type oxides, BaCe03 and SrCe03 based compositions show high protonic conductivities but strong resistance to densification. X-ray diffraction studies on sintered specimens of BaCe0.85Y0.1503-6 show multi-phase formation which was found to show dependence upon powder synthesis method. Doping with SrTiO3 suppresses multi-phase formation and enhances grain growth. Conductivity measurements in temperature range of 200 to 1000 C were performed by ac impedance spectroscopy under dry and wet conditions. Sintering behavior, phase formation and conductivity results will be reported.
SPAR electrophoretic separation experiments, part 2
NASA Technical Reports Server (NTRS)
Cosmi, F. M.
1978-01-01
The opportunity to use a sounding rocket for separation experiments is a logical continuation of earlier electrophoresis demonstrations and experiments. A free-flow electrophoresis system, developed under the Advanced Applications Flight Experiment (AAFE) Program, was designed so that it would fit into a rocket payload. The SPAR program provides a unique opportunity to complete the intial stages of microgravity testing prior to any Shuttle applications. The objective of the work described in this report was to ensure proper operating parameters for the defined experimental samples to be used in the SPAR Electrophoretic Separation Experiment. Ground based experiments were undertaken not only to define flight parameters but also to serve as a point of comparison for flight results. Possible flight experiment problem areas were also studied such as sample interaction due to sedimentation, concentration effects and storage effects. Late in the program anomalies of field strengths and buffer conductivities were also investigated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Espanol, C.E.
1960-01-01
The effect of the appearance of localized perturbations on the separation factor and operation time of a thermal diffusion column is studied. The separation factor of a column was obtained experimentally and the enrichment was recorded continuously as a function of time by measurement of the thermal conductivity of the gaseous mixture at the foot and head of the column. A mixture of Ar and CO/sub 2/ was used as it behaves as an isotopic mixture. The results showed the linear decrease of the separation factor with the number of stages and the operation time practically does not vary. Themore » introduction of localized turbulences in a thermal diffusion column reduces the column yield. (J.S.R.)« less
Autonomous oxygen production for a Mars return vehicle
NASA Technical Reports Server (NTRS)
Ash, R. L.; Richter, R.; Dowler, W. L.; Hanson, J. A.; Uphoff, C. W.
1982-01-01
The way in which a chemical processor that uses the Martian atmosphere as its only feedstock, thereby reducing the mass that must be launched from earth, can help to return a surface sample from Mars from a single Space Shuttle launch is described. Richter's (1981) study on both the theoretical and experimental aspects of oxygen separation using yttria-stabilized zirconia membranes is cited. Here, separation is accomplished by applying a voltage across the membrane which results in the selective conduction of oxygen ions from one side to the other. It is noted that by using thermal dissociation of the carbon dioxide in the Martian atmosphere to produce oxygen (and carbon monoxide), these zirconia electrolytic cells can be employed to separate oxygen from the atmospheric stream. Descriptions are also given of atmospheric filtration, atmospheric compression, and waste heat recovery, and of the oxygen precooler and oxygen compressor.
Qiu, Hongdeng; Zhang, Qinghua; Chen, Limei; Liu, Xia; Jiang, Shengxiang
2008-08-01
Separations of common inorganic anions were carried out on ODS columns coated with two long-chain alkylimidazolium ionic liquids ([C(12)MIm]Br and [C(14)MIm]Br) as new cationic surfactants for ion chromatography. With phthalate buffer solution as the mobile phases and non-suppressed conductivity detection, high column efficiencies and excellent selectivity were obtained in the separation of inorganic anions. Chromatographic parameters are calculated and the results show that the coated column possesses significant potential for the analysis of some inorganic anions such as CH(3)COO(-), IO(3)(-), Cl(-), BrO(3)(-), NO(2)(-), Br(-), NO(3)(-), SO(4)(2-), I(-), BF(4)(-), and SCN(-). The effect of eluent pH values on the separation of anions has been studied on the column coated with [C(12)MIm]Br. The stability of the coated columns was also examined.
Wu, Jiang; Li, Jia; Xu, Zhenming
2008-07-15
Electrostatic separation is an effective and environmentally friendly method for recycling comminuted waste printed circuit boards (PCB). As a classical separator, the roll-type corona-electrostatic separator (RTS) has some advantages in this field. However, there are still some notable problems, such as the middling products and their further treatment, impurity of nonconductive products because of the aggregation of fine particles, and stability of the separation process and balance between the production capacity and the separation quality. To overcome these problems, a conception of two-step separation is presented, and a new two-roll type corona-electrostatic separator (T-RTS) was built As compared to RTS, the conductive products increase by 8.9%, the middling products decrease by 45%, and the production capacity increases by 50% in treating comminuted PCB wastes by T-RTS. In addition, the separation process in T-RTS is more stable. Therefore, T-RTS is a promising separator for recycling comminuted PCB.
ERIC Educational Resources Information Center
Silvey, Brian A.; Koerner, Bryan D.
2016-01-01
We investigated the effects of expressive and unexpressive conducting on secondary school band members' and experts' audio evaluations of band performance expressivity. A conductor, who demonstrated either expressive or unexpressive conducting techniques, led both an eighth-grade and a high school band in four separate "run-throughs" of…
5 CFR 5501.102 - Designation of HHS components as separate agencies.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Designation of HHS components as separate agencies. 5501.102 Section 5501.102 Administrative Personnel DEPARTMENT OF HEALTH AND HUMAN SERVICES SUPPLEMENTAL STANDARDS OF ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF HEALTH AND HUMAN SERVICES § 5501...
5 CFR 5501.102 - Designation of HHS components as separate agencies.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Designation of HHS components as separate agencies. 5501.102 Section 5501.102 Administrative Personnel DEPARTMENT OF HEALTH AND HUMAN SERVICES SUPPLEMENTAL STANDARDS OF ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF HEALTH AND HUMAN SERVICES § 5501...
5 CFR 5501.102 - Designation of HHS components as separate agencies.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 5 Administrative Personnel 3 2014-01-01 2014-01-01 false Designation of HHS components as separate agencies. 5501.102 Section 5501.102 Administrative Personnel DEPARTMENT OF HEALTH AND HUMAN SERVICES SUPPLEMENTAL STANDARDS OF ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF HEALTH AND HUMAN SERVICES § 5501...
5 CFR 5501.102 - Designation of HHS components as separate agencies.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Designation of HHS components as separate agencies. 5501.102 Section 5501.102 Administrative Personnel DEPARTMENT OF HEALTH AND HUMAN SERVICES SUPPLEMENTAL STANDARDS OF ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF HEALTH AND HUMAN SERVICES § 5501...
5 CFR 5501.102 - Designation of HHS components as separate agencies.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Designation of HHS components as separate agencies. 5501.102 Section 5501.102 Administrative Personnel DEPARTMENT OF HEALTH AND HUMAN SERVICES SUPPLEMENTAL STANDARDS OF ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF HEALTH AND HUMAN SERVICES § 5501...
Report #11-R-0248, June 7, 2011. We conducted an unannounced site visit of the Clifton Street Sewer Separation and Water Main Replacement Projects in the City of Portland, Maine, from June 15 through June 17, 2009.
LABORATORY EVALUATION OF METHODS TO SEPARATE FINE GRAINED SEDIMENT FROM STORM WATER
A literature survey had been conducted by the St. Anthony Falls Hydraulic laboratory to assess various methods for separation of sediment from storm water at construction sites. Two methods have shown some promise in this application, and a research program was initiated with the...
NASA Astrophysics Data System (ADS)
Li, Yajie; Pu, Hongting
2018-04-01
Polypropylene (PP)/polyethylene (PE) multilayer separators with cellular-like submicron pore structure for lithium-ion battery are efficiently fabricated by the combination of multilayer coextrusion (MC) and thermal induced phase separation (TIPS). The as-prepared separators, referred to as MC-TIPS PP/PE, not only show efficacious thermal shutdown function and wider shutdown temperature window, but also exhibit higher thermal stability than the commercial separator with trilayer construction of PP and PE (Celgard® 2325). The dimensional shrinkage of MC-TIPS PP/PE can be negligible until 160 °C. In addition, compared to the commercial separator, MC-TIPS PP/PE exhibits higher porosity and electrolyte uptake, leading to higher ionic conductivity and better battery performances. The above-mentioned fascinating characteristics with the convenient preparation process make MC-TIPS PP/PE a promising candidate for the application as high performance lithium-ion battery separators.
Walker, Robert; Logan, T K; Jordan, Carol E; Campbell, Jacquelyn C
2004-04-01
Given the number of divorces that occur each year as well as the high rates of intimate partner violence, it is critical that divorce/separation and victimization be considered in research and in clinical practice with women. However, the separation/divorce research and victimization research has often been conducted independently, with limited attention to integration. The integration of these two domains is critically important in facilitating the understanding of these issues for women. This article has 5 main purposes: (a) to review the research on the general consequences of separation; (b) to review the research on the consequences of separation when children are involved; (c) to review the research on the consequences of victimization; (d) to integrate the separation and victimization research to examine separation in the context of victimization; and (e) to discuss the implications of separation in the context of victimization for practice and research.
Measurement of interfacial thermal conductance in Lithium ion batteries
NASA Astrophysics Data System (ADS)
Gaitonde, Aalok; Nimmagadda, Amulya; Marconnet, Amy
2017-03-01
Increasing usage and recent accidents due to Lithium ion (Li-ion) batteries exploding or catching on fire has inspired research on the thermal management of these batteries. In cylindrical 18650 cells, heat generated during the charge/discharge cycle must dissipate to the surrounding through its metallic case due to the poor thermal conductivity of the jelly roll, which is spirally wound with many interfaces between electrodes and the polymeric separator. This work develops a technique to measure the thermal resistance across the case-separator interface, which ultimately limits heat transfer out of the jelly roll. Commercial 18650 batteries are discharged and opened using a battery disassembly tool, and the 25 μm thick separator and the 200 μm thick metallic case are harvested to make samples. A miniaturized version of the conventional reference bar method (ASTM astm:D5470)
Bhagat, Ali Asgar S; Hou, Han Wei; Li, Leon D; Lim, Chwee Teck; Han, Jongyoon
2011-06-07
Blood is a highly complex bio-fluid with cellular components making up >40% of the total volume, thus making its analysis challenging and time-consuming. In this work, we introduce a high-throughput size-based separation method for processing diluted blood using inertial microfluidics. The technique takes advantage of the preferential cell focusing in high aspect-ratio microchannels coupled with pinched flow dynamics for isolating low abundance cells from blood. As an application of the developed technique, we demonstrate the isolation of cancer cells (circulating tumor cells (CTCs)) spiked in blood by exploiting the difference in size between CTCs and hematologic cells. The microchannel dimensions and processing parameters were optimized to enable high throughput and high resolution separation, comparable to existing CTC isolation technologies. Results from experiments conducted with MCF-7 cells spiked into whole blood indicate >80% cell recovery with an impressive 3.25 × 10(5) fold enrichment over red blood cells (RBCs) and 1.2 × 10(4) fold enrichment over peripheral blood leukocytes (PBL). In spite of a 20× sample dilution, the fast operating flow rate allows the processing of ∼10(8) cells min(-1) through a single microfluidic device. The device design can be easily customized for isolating other rare cells from blood including peripheral blood leukocytes and fetal nucleated red blood cells by simply varying the 'pinching' width. The advantage of simple label-free separation, combined with the ability to retrieve viable cells post enrichment and minimal sample pre-processing presents numerous applications for use in clinical diagnosis and conducting fundamental studies.
ERIC Educational Resources Information Center
Ha, Tran Thi Thu; Fisher, Jane R. W.
2011-01-01
The purpose of this study was to explore the expectations of parents in a remote mountainous commune in Vietnam about sexual and reproductive health (SRH) education for their children. Separate in-depth interviews were conducted with 34 parents of eight-year-old children and key informants including a principal, a teacher and staff of the Youth…
USDA-ARS?s Scientific Manuscript database
Three separate studies were conducted to investigate the life-long effect of creep feeding, creep feeding energy source (soybean hulls, SC, or corn, CC) and interactive effects of creep feed with backgrounding dietary energy source (soybean hulls, SBR, or corn, CBR) on calf growth performance, carca...
ERIC Educational Resources Information Center
Hanrahan, Fidelma; Banerjee, Robin
2017-01-01
An in-depth, longitudinal, idiographic study examined the impact of theatre and drama involvement on marginalised young people. Semi-structured interviews, at three separate time points over 2 years, were conducted with four young people (15-21 years of age) involved in a theatre project. Interpretative phenomenological analysis suggested that…
Using of Video Modeling in Teaching a Simple Meal Preparation Skill for Pupils of Down Syndrome
ERIC Educational Resources Information Center
AL-Salahat, Mohammad Mousa
2016-01-01
The current study aimed to identify the impact of video modeling upon teaching three pupils with Down syndrome the skill of preparing a simple meal (sandwich), where the training was conducted in a separate classroom in schools of normal students. The training consisted of (i) watching the video of an intellectually disabled pupil, who is…
ERIC Educational Resources Information Center
Hover, Paige Amber
2014-01-01
This study compared first generation and non-first generation doctoral students' levels of perceived stress, sense of coherence, and mindfulness. These variables were assessed both separately for each trainee group and in hypothesized relationships with each other. In addition, moderator analyses were conducted to assess whether key relationships…
Lagrangian Studies of Lateral Mixing
2017-09-19
instabilities. A towed profiler was used to conduct synoptic, 4D surveys to resolve submesoscale variability. Results include finding that: (i...OBJECTIVES The LATMIX2 experimental program focused on two potential mechanisms for lateral mixing: 1. Submesoscale turbulence, generated by...Figure 1. LATMIX2 surveys . Red (black) lines mark Knorr (Atlantis) tracks plotted over SST images from 2 separate days, corresponding to the 2
Family Separation and Reunion: Families of Prisoners of War and Servicemen Missing in Action.
ERIC Educational Resources Information Center
McCubbin, Hamilton I., Ed.; And Others
This book is an outgrowth of two major projects. The first is a research investigation being conducted by the Center for Prisoner of War Studies, and the second is the extension of services to families. The volume encompasses three major periods: the waiting period (early 1960's to February 1973); the repatriation period (February 1973 to April…
USDA-ARS?s Scientific Manuscript database
A study was conducted to determine the effect of feeding yeast cell wall (YCW) products on the physiological and acute phase responses of crossbred newly-received heifers to an endotoxin challenge. Heifers (n = 24; 219 ± 2.4 kg) were separated into treatment groups receiving a Control diet (n = 8), ...
Factors Affecting Stakeholders' Willingness to Pay to Prevent the Spread of Aquatic Nuisance Species
ERIC Educational Resources Information Center
Blaine, Thomas W.; Lichtkoppler, Frank R.
2016-01-01
Physical separation of the Great Lakes and Mississippi River basins has been identified as the most effective method for preventing the transfer of aquatic nuisance species, particularly Asian carp, from the Mississippi River Basin to the Great Lakes. The U.S. Army Corps of Engineers selected Extension to conduct a study of a key stakeholder…
Separating Fact and Fiction: The Real Story of Corpus Use in Language Teaching
ERIC Educational Resources Information Center
Boulton, Alex
2013-01-01
This paper investigates uses of corpora in language learning ("data-driven learning") through analysis of a 600K-word corpus of empirical research papers in the field. The corpus can tell us much--the authors and the countries the studies are conducted in, the types of publication, and so on. The corpus investigation itself starts with…
Indoor air quality in public buildings. Volume 2
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sheldon, L.; Zelon, H.; Sickles, J.
Two separate but closely related studies of exposures to volatile organic compounds (VOCs) in buildings where people spend long periods of time were conducted. This report summarizes results obtained in six buildings: a new hospital, office and nursing home and another office, office/school, and nursing home. At each building sampling was performed at three indoor locations and a single outdoor location.
USDA-ARS?s Scientific Manuscript database
A study was conducted to examine the effects of three diets supplemented with organic selenium (Se) and zinc (Zn) on the performance of Cochin exotic breeder hens. Cochin hens (n=120) and males (n=12) at 42 wks of age were separated into four treatment groups with three replications per treatment. ...
Study on the separation effect of high-speed ultrasonic vibration cutting.
Zhang, Xiangyu; Sui, He; Zhang, Deyuan; Jiang, Xinggang
2018-07-01
High-speed ultrasonic vibration cutting (HUVC) has been proven to be significantly effective when turning Ti-6Al-4V alloy in recent researches. Despite of breaking through the cutting speed restriction of the ultrasonic vibration cutting (UVC) method, HUVC can also achieve the reduction of cutting force and the improvements in surface quality and cutting efficiency in the high-speed machining field. These benefits all result from the separation effect that occurs during the HUVC process. Despite the fact that the influences of vibration and cutting parameters have been discussed in previous researches, the separation analysis of HUVC should be conducted in detail in real cutting situations, and the tool geometry parameters should also be considered. In this paper, three situations are investigated in details: (1) cutting without negative transient clearance angle and without tool wear, (2) cutting with negative transient clearance angle and without tool wear, and (3) cutting with tool wear. And then, complete separation state, partial separation state and continuous cutting state are deduced according to real cutting processes. All the analysis about the above situations demonstrate that the tool-workpiece separation will take place only if appropriate cutting parameters, vibration parameters, and tool geometry parameters are set up. The best separation effect was obtained with a low feedrate and a phase shift approaching 180 degrees. Moreover, flank face interference resulted from the negative transient clearance angle and tool wear contributes to an improved separation effect that makes the workpiece and tool separate even at zero phase shift. Finally, axial and radial transient cutting force are firstly obtained to verify the separation effect of HUVC, and the cutting chips are collected to weigh the influence of flank face interference. Copyright © 2018 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fort, D.J.; Stover, E.L.
1996-12-31
An evaluation of the effects of low-level copper and pentachlorophenol exposure on various early life stages of the South African clawed frog, Xenopus laevis, was performed using stage-specific and long-term continuous exposures. Stage-specific exposure experiments were conducted such that separate subsets of embryos and larvae from the same clutch were exposed to two toxicants, copper and pentachlorphenol, from 0 d to 4 d (standard Frog Embryo Teratogenesis Assay--Xenopus [FETAX]), 4 d to 8 d, 8 d to 12 d, and 12 d to 16 d. Results from two separate concentration-response experiments indicated that sensitivity to either toxicant increased in eachmore » successive time period. Longer-term exposure studies conducted for 60 to 75 days indicated that copper, but not pentachlorophenol induced reduction deficiency malformations of the hind limb at concentrations as low as 0.05 mg/L. Pentachlorophenol concentrations as low as 0.5 {micro}g/L inhibited tail resorption. However, copper did not adversely affect the process of tail resorption. These results indicated that studies evaluating longer-term developmental processes are important in ecological hazard evaluation.« less
Effect of chronic copper and pentachlorophenol exposure to early life stages of Xenopus laevis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fort, D.J.; Stover, E.L.
1995-12-31
An evaluation of the effects of low-level copper and pentachlorophenol exposure on various early life stages of the South African clawed frog, Xenopus laevis was performed using stage-specific and long-term continuous exposures. Stage-specific exposure experiments were conducted such that separate subsets of embryos and larvae from the same clutch were exposed to two toxicants, copper and pentachlorophenol, from 0 d to 4 d (standard Frog Embryo Teratagenesis Assay Xenopus [FETAX]), 4 d to 8 d, 8 d to 12 d, and 12 d to 16 d. Results from two separate concentration-response experiments indicated that sensitivity to either toxicant increased inmore » each successive time period. Continuous exposure studies conducted for 60 to 75 days indicated that copper, but not pentachlorophenol induced reduction deficiency malformations of the hind limb at concentrations as low as 0.05 mg/L. Pentachlorophenol concentrations as low as 0.5/{micro}g/L inhibited tail resorption. However, copper did not adversely affect the process of tail resorption. These results indicated that studies evaluating longer-term developmental processes are important in ecological hazard evaluation.« less
Stacking fault induced tunnel barrier in platelet graphite nanofiber
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lan, Yann-Wen, E-mail: chiidong@phys.sinica.edu.tw, E-mail: ywlan@phys.sinica.edu.tw; Chang, Yuan-Chih; Chang, Chia-Seng
A correlation study using image inspection and electrical characterization of platelet graphite nanofiber devices is conducted. Close transmission electron microscopy and diffraction pattern inspection reveal layers with inflection angles appearing in otherwise perfectly stacked graphene platelets, separating nanofibers into two domains. Electrical measurement gives a stability diagram consisting of alternating small-large Coulomb blockade diamonds, suggesting that there are two charging islands coupled together through a tunnel junction. Based on these two findings, we propose that a stacking fault can behave as a tunnel barrier for conducting electrons and is responsible for the observed double-island single electron transistor characteristics.
Garlic consumption and colorectal cancer risk in man: a systematic review and meta-analysis.
Chiavarini, Manuela; Minelli, Liliana; Fabiani, Roberto
2016-02-01
Colorectal cancer shows large incidence variations worldwide that have been attributed to different dietary factors. We conducted a meta-analysis on the relationship between garlic consumption and colorectal cancer risk. We systematically reviewed publications obtained by searching ISI Web of Knowledge, MEDLINE and EMBASE literature databases. We extracted the risk estimate of the highest and the lowest reported categories of intake from each study and conducted meta-analysis using a random-effects model. The pooled analysis of all fourteen studies, seven cohort and seven case-control, indicated that garlic consumption was not associated with colorectal cancer risk (OR=0·93; 95 % CI 0·82, 1·06, P=0·281; I 2=83·6 %, P≤0·001). Separate analyses on the basis of cancer sites and sex also revealed no statistically significant effects on cancer risk. However, when separately analysed on the basis of study type, we found that garlic was associated with an approximately 37 % reduction in colorectal cancer risk in the case-control studies (combined risk estimate=0·63, 95 % CI 0·48, 0·82, P=0·001; I 2=75·6 %, P≤0·001). Our results suggest that consumption of garlic is not associated with a reduced colorectal cancer risk. Further investigations are necessary to clarify the discrepancy between results obtained from different types of epidemiological studies.
Electrical conductivity measurements of bacterial nanowires from Pseudomonas aeruginosa
NASA Astrophysics Data System (ADS)
Maruthupandy, Muthusamy; Anand, Muthusamy; Maduraiveeran, Govindhan; Sait Hameedha Beevi, Akbar; Jeeva Priya, Radhakrishnan
2015-12-01
The extracellular appendages of bacteria (flagella) that transfer electrons to electrodes are called bacterial nanowires. This study focuses on the isolation and separation of nanowires that are attached via Pseudomonas aeruginosa bacterial culture. The size and roughness of separated nanowires were measured using transmission electron microscopy (TEM) and atomic force microscopy (AFM), respectively. The obtained bacterial nanowires indicated a clear image of bacterial nanowires measuring 16 nm in diameter. The formation of bacterial nanowires was confirmed by microscopic studies (AFM and TEM) and the conductivity nature of bacterial nanowire was investigated by electrochemical techniques. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), which are nondestructive voltammetry techniques, suggest that bacterial nanowires could be the source of electrons—which may be used in various applications, for example, microbial fuel cells, biosensors, organic solar cells, and bioelectronic devices. Routine analysis of electron transfer between bacterial nanowires and the electrode was performed, providing insight into the extracellular electron transfer (EET) to the electrode. CV revealed the catalytic electron transferability of bacterial nanowires and electrodes and showed excellent redox activities. CV and EIS studies showed that bacterial nanowires can charge the surface by producing and storing sufficient electrons, behave as a capacitor, and have features consistent with EET. Finally, electrochemical studies confirmed the development of bacterial nanowires with EET. This study suggests that bacterial nanowires can be used to fabricate biomolecular sensors and nanoelectronic devices.
Cho, JaeJin; Park, HyunWook
2018-05-17
To acquire interleaved bipolar data and reconstruct the full data using low-rank property for water fat separation. Bipolar acquisition suffers from issues related to gradient switching, the opposite gradient polarities, and other system imperfections, which prevent accurate water-fat separation. In this study, an interleaved bipolar acquisition scheme and a low-rank reconstruction method were proposed to reduce issues from the bipolar gradients while achieving a short imaging time. The proposed interleaved bipolar acquisition scheme collects echo-time signals from both gradient polarities; however, the sequence increases the imaging time. To reduce the imaging time, the signals were subsampled at every dimension of k-space. The low-rank property of the bipolar acquisition was defined and exploited to estimate the full data from the acquired subsampled data. To eliminate the bipolar issues, in the proposed method, the water-fat separation was performed separately for each gradient polarity, and the results for the positive and negative gradient polarities were combined after the water-fat separation. A phantom study and in-vivo experiments were conducted on a 3T Siemens Verio system. The results for the proposed method were compared with the results of the fully sampled interleaved bipolar acquisition and Soliman's method, which was the previous water-fat separation approach for reducing the issues of bipolar gradients and accelerating the interleaved bipolar acquisition. The proposed method provided accurate water and fat images without the issues of bipolar gradients and demonstrated a better performance compared with the results of the previous methods. The water-fat separation using the bipolar acquisition has several benefits including a short echo-spacing time. However, it suffers from bipolar-gradient issues such as strong gradient switching, system imperfection, and eddy current effects. This study demonstrated that accurate water-fat separated images can be obtained using the proposed interleaved bipolar acquisition and low-rank reconstruction by using the benefits of the bipolar acquisition while reducing the bipolar-gradient issues with a short imaging time. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
PEM fuel cell bipolar plate material requirements for transportation applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Borup, R.L.; Stroh, K.R.; Vanderborgh, N.E.
1996-04-01
Cost effective bipolar plates are currently under development to help make proton exchange membrane (PEM) fuel cells commercially viable. Bipolar plates separate individual cells of the fuel cell stack, and thus must supply strength, be electrically conductive, provide for thermal control of the fuel stack, be a non-porous materials separating hydrogen and oxygen feed streams, be corrosion resistant, provide gas distribution for the feed streams and meet fuel stack cost targets. Candidate materials include conductive polymers and metal plates with corrosion resistant coatings. Possible metals include aluminium, titanium, iron/stainless steel and nickel.
Shasby, Mark; Dolloff, C. Andrew; Hicke, Jeffrey A.; Marcot, Bruce G.; McCarl, Bruce; McMahon, Gerard; Morton, John M.
2017-01-01
This report primarily addresses the first two purposes of the review while providing comments on the third as identified by the science review team (SRT). A separate report of recommendations for the recompetition, based upon compiled observation from all three reviews conducted in 2016, was submitted to NCCWSC on April 15, 2016 to assist with the development of recompetition documents. To further address host-university administrative competencies and efficiencies, separate interviews of host-university faculty and administrators were conducted by NCCWSC staff in conjunction with the on-site component of the reviews.
Separation of thorium and uranium in nitric acid solution using silica based anion exchange resin.
Chen, Yanliang; Wei, Yuezhou; He, Linfeng; Tang, Fangdong
2016-09-30
To separate thorium and uranium in nitric acid solution using anion exchange process, a strong base silica-based anion exchange resin (SiPyR-N4) was synthesized. Batch experiments were conducted and the separation factor of thorium and uranium in 9M nitric acid was about 10. Ion exchange chromatography was applied to separate thorium and uranium in different ratios. Uranium could be eluted by 9M nitric acid and thorium was eluted by 0.1M nitric acid. It was proved that thorium and uranium can be separated and recovered successfully by this method. Copyright © 2016 Elsevier B.V. All rights reserved.
1999-03-01
data on geologic setting, metallic and industrial minerals, gemstones, uranium, geothermal resources, and oil and gas resources on the NAFR lands...were conducted during the RFA. The SWMUs and AOCs found on NAFR include ECM sites, oil /water separators, acid neutralizing basins and oil interceptors...inspected. No specific recommendations provided. Area 10 Oil /Water Separator Bldg 145 Oil /water separator handles influent from wash and rinse basins
Examining Dynamic Stall for an Oscillating NACA 4412 Hydrofoil
NASA Astrophysics Data System (ADS)
McVay, Eric; Lang, Amy; Gamble, Lawren; Bradshaw, Michael
2013-11-01
Dynamic stall is unsteady separation that occurs when a hydrofoil pitches through the static stall angle while simultaneously experiencing a rapid change in angle of attack. The NACA 4412 hydrofoil was selected for this research because it has strong trailing edge turbulent boundary layer separation characteristics. General dynamic stall angle of attack for approximately symmetric airfoils has been recorded to occur at 24 degrees, with separation beginning at about 16 degrees. It is predicted that the boundary layer will stay attached at a higher angle of attack because of the cambered geometry of the hydrofoil. It is also hypothesized that the boundary layer separation occurs closer to the trailing edge and that the dynamic stall angle of attack occurs somewhere between 24 and 28 degrees for the oscillating NACA 4412 hydrofoil. This research was conducted in a water tunnel facility using Time Resolved Digital Particle Image Velocimetry (TR-DPIV). The hydrofoil was pitched up from 0 to 30 degrees at Reynolds numbers of 60,000, 80,000 and 100,000. Flow characteristics, dynamic stall angles of attack, and points of boundary layer separation were compared at each velocity with both tripped and un-tripped surfaces. Follow-on research will be conducted using flow control techniques from sharks and dolphins to examine the potential benefits of these natural designs for separation control. Support for this research by NSF REU Grant #1062611 and CBET Grant #0932352 is gratefully acknowledged.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kojima, S.; Yokosawa, M.; Matsuyama, M.
To study the practical application of a tritium separation process using Self-Developing Gas Chromatography (SDGC) using a Pd-Pt alloy, intermediate scale-up experiments (22 mm ID x 2 m length column) and the development of a computational simulation method have been conducted. In addition, intermediate scale production of Pd-Pt powder has been developed for the scale-up experiments.The following results were obtained: (1) a 50-fold scale-up from 3 mm to 22 mm causes no significant impact on the SDGC process; (2) the Pd-Pt alloy powder is applicable to a large size SDGC process; and (3) the simulation enables preparation of a conceptualmore » design of a SDGC process for tritium separation.« less
NASA Technical Reports Server (NTRS)
Lozito, Sandy; Mackintosh, Margaret-Anne; DiMeo, Karen; Kopardekar, Parimal
2002-01-01
A simulation was conducted to examine the effect of shared air/ground authority when each is equipped with enhanced traffic- and conflict-alerting systems. The potential benefits of an advanced air traffic management (ATM) concept referred to as "free flight" include improved safety through enhanced conflict detection and resolution capabilities, increased flight-operations management, and better decision-making tools for air traffic controllers and flight crews. One element of the free-flight concept suggests shifting aircraft separation responsibility from air traffic controllers to flight crews, thereby creating an environment with "shared-separation" authority. During FY00. NASA, the Federal Aviation Administration (FAA), and the Volpe National Transportation Systems Center completed the first integrated, high-fidelity, real-time, human-in-the-loop simulation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hona, Ram Krishna; Huq, Ashfia; Mulmi, Suresh
The ability to control electrical properties and magnetism by varying the crystal structure using the effect of the A-site cation in oxygen-deficient perovskites has been studied in AA’Fe 2O 6-δ, where A=Sr, Ca and A’= Sr. The structure of Sr 2Fe 2O 6-δ, synthesized at 1250 °C in air, contains dimeric units of FeO 5 square-pyramids separated by FeO 6 octahedra. Here we show that this ordering scheme can be transformed by changing the A-site cations from Sr to Ca. This leads to a structure where layers of corner-sharing FeO 6 octahedra are separated by chains of FeO 4 tetrahedra.more » Through systematic variation of the A-site cations, we have determined the average ionic radius required for this conversion to be ~1.41 Å. We have demonstrated that the magnetic structure is also transformed. The Sr 2 compound has an incommensurate magnetic structure, where magnetic moments are in spin-density wave state, aligning perpendicular to the body diagonal of the unit cell. With the aid of neutron diffraction experiments at 10 K and 300 K, we have shown that the magnetic structure is converted into a long-range G-type antiferromagnetic system when one Sr is replaced by Ca. In this G-type ordering scheme, the magnetic moments align in the 001 direction, antiparallel to their nearest neighbors. We have also performed variable-temperature electrical conductivity studies on these materials in the temperature range 298 – 1073 K. These studies have revealed the transformation of charge transport properties, where the metallic behavior of the Sr 2-compound is converted into semiconductivity in the CaSr-material. The trend of conductivity as a function of temperature is reversed upon changing the A-site cation. The conductivity of the Sr 2 compound shows a downturn, while the conductivity of the CaSr material increases as a function of temperature. We have also shown that the CaSr-compound exhibits temperature-dependent behavior typical of a mixed ionic-electronic conducting system.« less
Hona, Ram Krishna; Huq, Ashfia; Mulmi, Suresh; ...
2017-08-09
The ability to control electrical properties and magnetism by varying the crystal structure using the effect of the A-site cation in oxygen-deficient perovskites has been studied in AA’Fe 2O 6-δ, where A=Sr, Ca and A’= Sr. The structure of Sr 2Fe 2O 6-δ, synthesized at 1250 °C in air, contains dimeric units of FeO 5 square-pyramids separated by FeO 6 octahedra. Here we show that this ordering scheme can be transformed by changing the A-site cations from Sr to Ca. This leads to a structure where layers of corner-sharing FeO 6 octahedra are separated by chains of FeO 4 tetrahedra.more » Through systematic variation of the A-site cations, we have determined the average ionic radius required for this conversion to be ~1.41 Å. We have demonstrated that the magnetic structure is also transformed. The Sr 2 compound has an incommensurate magnetic structure, where magnetic moments are in spin-density wave state, aligning perpendicular to the body diagonal of the unit cell. With the aid of neutron diffraction experiments at 10 K and 300 K, we have shown that the magnetic structure is converted into a long-range G-type antiferromagnetic system when one Sr is replaced by Ca. In this G-type ordering scheme, the magnetic moments align in the 001 direction, antiparallel to their nearest neighbors. We have also performed variable-temperature electrical conductivity studies on these materials in the temperature range 298 – 1073 K. These studies have revealed the transformation of charge transport properties, where the metallic behavior of the Sr 2-compound is converted into semiconductivity in the CaSr-material. The trend of conductivity as a function of temperature is reversed upon changing the A-site cation. The conductivity of the Sr 2 compound shows a downturn, while the conductivity of the CaSr material increases as a function of temperature. We have also shown that the CaSr-compound exhibits temperature-dependent behavior typical of a mixed ionic-electronic conducting system.« less
Mars sample return mission architectures utilizing low thrust propulsion
NASA Astrophysics Data System (ADS)
Derz, Uwe; Seboldt, Wolfgang
2012-08-01
The Mars sample return mission is a flagship mission within ESA's Aurora program and envisioned to take place in the timeframe of 2020-2025. Previous studies developed a mission architecture consisting of two elements, an orbiter and a lander, each utilizing chemical propulsion and a heavy launcher like Ariane 5 ECA. The lander transports an ascent vehicle to the surface of Mars. The orbiter performs a separate impulsive transfer to Mars, conducts a rendezvous in Mars orbit with the sample container, delivered by the ascent vehicle, and returns the samples back to Earth in a small Earth entry capsule. Because the launch of the heavy orbiter by Ariane 5 ECA makes an Earth swing by mandatory for the trans-Mars injection, its total mission time amounts to about 1460 days. The present study takes a fresh look at the subject and conducts a more general mission and system analysis of the space transportation elements including electric propulsion for the transfer. Therefore, detailed spacecraft models for orbiters, landers and ascent vehicles are developed. Based on that, trajectory calculations and optimizations of interplanetary transfers, Mars entries, descents and landings as well as Mars ascents are carried out. The results of the system analysis identified electric propulsion for the orbiter as most beneficial in terms of launch mass, leading to a reduction of launch vehicle requirements and enabling a launch by a Soyuz-Fregat into GTO. Such a sample return mission could be conducted within 1150-1250 days. Concerning the lander, a separate launch in combination with electric propulsion leads to a significant reduction of launch vehicle requirements, but also requires a large number of engines and correspondingly a large power system. Therefore, a lander performing a separate chemical transfer could possibly be more advantageous. Alternatively, a second possible mission architecture has been developed, requiring only one heavy launch vehicle (e.g., Proton). In that case the lander is transported piggyback by the electrically propelled orbiter.
Autonomic nervous system response patterns specificity to basic emotions.
Collet, C; Vernet-Maury, E; Delhomme, G; Dittmar, A
1997-01-12
The aim of this study was to test the assumption that the autonomic nervous system responses to emotional stimuli are specific. A series of six slides was randomly presented to the subjects while six autonomic nervous system (ANS) parameters were recorded: skin conductance, skin potential, skin resistance, skin blood flow, skin temperature and instantaneous respiratory frequency. Each slide induced a basic emotion: happiness, surprise, anger, fear, sadness and disgust. Results have been first considered with reference to electrodermal responses (EDR) and secondly through thermo-vascular and respiratory variations. Classical as well as original indices were used to quantify autonomic responses. The six basic emotions were distinguished by Friedman variance analysis. Thus, ANS values corresponding to each emotion were compared two-by-two. EDR distinguished 13 emotion-pairs out of 15. 10 emotion-pairs were separated by skin resistance as well as skin conductance ohmic perturbation duration indices whereas conductance amplitude was only capable of distinguishing 7 emotion-pairs. Skin potential responses distinguished surprise and fear from sadness, and fear from disgust, according to their elementary pattern analysis in form and sign. Two-by-two comparisons of skin temperature, skin blood flow (estimated by the new non-oscillary duration index) and instantaneous respiratory frequency, enabled the distinction of 14 emotion-pairs out of 15. 9 emotion-pairs were distinguished by the non-oscillatory duration index values. Skin temperature was demonstrated to be different i.e. positive versus negative in response to anger and fear. The instantaneous respiratory frequency perturbation duration index was the only one capable of separating sadness from disgust. From the six ANS parameters study, different autonomic patterns were identified, each characterizing one of the six basic emotion used as inducing signals. No index alone, nor group of parameters (EDR and thermovascular for instance) were capable of distinguishing each emotion from another. However, electrodermal, thermo-vascular and respiratory responses taken as a whole, redundantly separated each emotion thus demonstrating the specificity of autonomic patterns.
NASA Astrophysics Data System (ADS)
Chwiej, T.
2016-10-01
We theoretically study the single electron magnetotransport in GaAs and InGaAs vertically stacked bilayer nanowires. In considered geometry, the tilted magnetic field is always perpendicular to the main (transport) axis of the quantum wire and, therefore its transverse and vertical components allow separately for changing the magnitude of intralayer and interlayer subbands mixing. We study the changes introduced to energy dispersion relation E(k) by tilted magnetic field of strength up to several tesla and analyze their origins for symmetric as well as asymmetric confining potentials in the growth direction. Calculated energy dispersion relations are thereafter used to show that the value of a conductance of the bilayer nanowire may abruptly rise as well as fall by few conductance quanta when the Fermi energy in nanosystem is changed. It is also shown that such conductance oscillations, in conjunction with spin Zeeman effect, may give a moderately spin polarized current in the bilayer nanowire.
DOE Office of Scientific and Technical Information (OSTI.GOV)
James K. Neathery; Gary Jacobs; Burtron H. Davis
In this reporting period, a fundamental filtration study was started to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. Slurry-phase FTS in slurry bubble column reactor systems is the preferred mode of production since the reaction is highly exothermic. Consequently, heavy wax products must be separated from catalyst particles before being removed from the reactor system. Achieving an efficient wax product separation from iron-based catalysts is one of the most challenging technical problems associated with slurry-phase FTS. The separation problem is further compounded by catalyst particle attrition and the formation of ultra-fine iron carbide and/or carbonmore » particles. Existing pilot-scale equipment was modified to include a filtration test apparatus. After undergoing an extensive plant shakedown period, filtration tests with cross-flow filter modules using simulant FTS wax slurry were conducted. The focus of these early tests was to find adequate mixtures of polyethylene wax to simulate FTS wax. Catalyst particle size analysis techniques were also developed. Initial analyses of the slurry and filter permeate particles will be used by the research team to design improved filter media and cleaning strategies.« less
Electro–optical properties of poly(vinyl acetate)/polyindole composite film
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhagat, D. J., E-mail: bhagatd@rediffmail.com; Dhokane, G. R.; Bajaj, N. S.
2016-05-06
In present work, electrical and optical properties of poly(vinyl acetate)/polyindole (PVAc/PIN) composite film are reported. The prepared composite was characterized via X–ray diffraction (XRD), UV–Vis spectroscopy and DC conductivity measurements. The polymer chain separation was determined using XRD analysis. An attempt has been made to study the temperature dependence of DC conductivity of PVAc/PIN composite in temperature range 308–373 K. The DC conductivity initially increases and reaches to 2.45×10–7 S/cm. The optical band gap value of composite is determined as 4.77 eV. The semiconducting nature of composite observed from electronic as well as optical band gap and Arrhenius behavior of DCmore » plot.« less
Alloying effects on superionic conductivity in lithium indium halides for all-solid-state batteries
NASA Astrophysics Data System (ADS)
Zevgolis, Alysia; Wood, Brandon C.; Mehmedović, Zerina; Hall, Alex T.; Alves, Thomaz C.; Adelstein, Nicole
2018-04-01
Alloying of anions is a promising engineering strategy for tuning ionic conductivity in halide-based inorganic solid electrolytes. We explain the alloying effects in Li3InBr6-xClx, in terms of strain, chemistry, and microstructure, using first-principles molecular dynamics simulations and electronic structure analysis. We find that strain and bond chemistry can be tuned through alloying and affect the activation energy and maximum diffusivity coefficient. The similar conductivities of the x = 3 and x = 6 compositions can be understood by assuming that the alloy separates into Br-rich and Cl-rich regions. Phase-separation increases diffusivity at the interface and in the expanded Cl-region, suggesting microstructure effects are critical. Similarities with other halide superionic conductors are highlighted.
A blind source separation approach for humpback whale song separation.
Zhang, Zhenbin; White, Paul R
2017-04-01
Many marine mammal species are highly social and are frequently encountered in groups or aggregations. When conducting passive acoustic monitoring in such circumstances, recordings commonly contain vocalizations of multiple individuals which overlap in time and frequency. This paper considers the use of blind source separation as a method for processing these recordings to separate the calls of individuals. The example problem considered here is that of the songs of humpback whales. The high levels of noise and long impulse responses can make source separation in underwater contexts a challenging proposition. The approach present here is based on time-frequency masking, allied to a noise reduction process. The technique is assessed using simulated and measured data sets, and the results demonstrate the effectiveness of the method for separating humpback whale songs.
NASA Astrophysics Data System (ADS)
Jeon, Han-Yong
2016-10-01
Geosynthetic separation boxes made from recycled polymeric materials were designed to increase the waste landfill amount and develop the hydraulic performance in steep slope sides in the waste landfills. To evaluate the advantages of these geosynthetic separation boxes, index tests were conducted in order to compare the geonet composites and geosynthetic separation boxes. The tensile strength retention of the geosynthetic separation box plates exposed to UV light and leachate solutions was better than that of the geonet composites. The drainage performance of the geosynthetic separation boxes was compared with that of the geonet composites at a slope angle corresponding to a real waste landfill site. The drainage performance of the geosynthetic separation box plates was better than that of the geonet composites.
Zhang, Jianjun; Yue, Liping; Kong, Qingshan; Liu, Zhihong; Zhou, Xinhong; Zhang, Chuanjian; Xu, Quan; Zhang, Bo; Ding, Guoliang; Qin, Bingsheng; Duan, Yulong; Wang, Qingfu; Yao, Jianhua; Cui, Guanglei; Chen, Liquan
2014-01-01
A sustainable, heat-resistant and flame-retardant cellulose-based composite nonwoven has been successfully fabricated and explored its potential application for promising separator of high-performance lithium ion battery. It was demonstrated that this flame-retardant cellulose-based composite separator possessed good flame retardancy, superior heat tolerance and proper mechanical strength. As compared to the commercialized polypropylene (PP) separator, such composite separator presented improved electrolyte uptake, better interface stability and enhanced ionic conductivity. In addition, the lithium cobalt oxide (LiCoO2)/graphite cell using this composite separator exhibited better rate capability and cycling retention than that for PP separator owing to its facile ion transport and excellent interfacial compatibility. Furthermore, the lithium iron phosphate (LiFePO4)/lithium cell with such composite separator delivered stable cycling performance and thermal dimensional stability even at an elevated temperature of 120°C. All these fascinating characteristics would boost the application of this composite separator for high-performance lithium ion battery. PMID:24488228
Fan, Hao; Tao, Fan; Wan, Hai-fang; Luo, Hong
2012-05-08
To evaluate risk factors associated with emergence agitation (EA) in pediatrics after general anesthesia. A prospective cohort study was conducted in 268 pediatric patients aged 2-9 years, who received general anesthesia for various operative procedures in our hospital between January 2008 and October 2011. The incidence of EA was assessed. Difficult parental-separation behavior, pharmacologic and non-pharmacologic interventions, and adverse events were also recorded. Univariate and multivariate analysis were used to determine the factors associated with EA. A p-value of less than 0.05 was considered significant. One hundred and sixteen children (43.3%) had EA, with an average duration of 9.1 ± 6.6 minutes. EA associated with adverse events occurred in 35 agitated children (30.2%). From univariate analysis, factors associated with EA were difficult parental-separation behavior, preschool age (2 - 5 years), and general anesthesia with sevoflurane. However, difficult parental-separation behavior, and preschool age were the only factors significantly associated with EA in the multiple Logistic regression analysis with OR = 3.091 (95%CI: 1.688, 5.465, P < 0.01) and OR = 1.965 (95%CI: 1.112, 3.318, P = 0.024), respectively. The present study indicated that the incidence of EA was high in PACU. Preschool children and difficult parental-separation behavior were the predictive factors of emergence agitation.
Split-Channel Ballistic Transport in an InSb Nanowire
NASA Astrophysics Data System (ADS)
Estrada Saldaña, Juan Carlos; Niquet, Yann-Michel; Cleuziou, Jean-Pierre; Lee, Eduardo J. H.; Car, Diana; Plissard, Sébastien R.; Bakkers, Erik P. A. M.; De Franceschi, Silvano
2018-04-01
We report an experimental study of one-dimensional (1D) electronic transport in an InSb semiconducting nanowire. Three bottom gates are used to locally deplete the nanowire creating a ballistic quantum point contact with only a few conducting channels. In a magnetic field, the Zeeman splitting of the corresponding 1D subbands is revealed by the emergence of conductance plateaus at multiples of $e^2$/h, yet we find a quantized conductance pattern largely dependent on the configuration of voltages applied to the bottom gates. In particular, we can make the first plateau disappear leaving a first conductance step of 2$e^2/h$, which is indicative of a remarkable two-fold subband degeneracy that can persist up to several Tesla. For certain gate voltage settings, we also observe the presence of discrete resonant states producing conductance features that can resemble those expected from the opening of a helical gap in the subband structure. We explain our experimental findings through the formation of two spatially separated 1D conduction channels.
Correlating morphology to dc conductivity in polymerized ionic liquids
NASA Astrophysics Data System (ADS)
Iacob, Ciprian; Matusmoto, Atsushi; Inoue, Tadashi; Runt, James
Polymerized ionic liquids (PILs) combine the attractive mechanical characteristics of polymers and unique physico-chemical properties of low molecular weight ionic liquids in the same material. PILs have shown remarkable advantages when employed in electrochemical devices such as dye-sensitized solar cells and lithium batteries, among others. Understanding their ionic transport mechanism is the key for designing highly conductive PILs. In the current study, the correlation between morphology and charge transport in two homologous series of PILs with systematic variation of the alkyl chain length and anions is investigated using broadband dielectric spectroscopy, rheology, differential scanning calorimetry and X-ray scattering. As the alkyl chain length increases, the backbone-to-backbone separation increases, and dc-conductivity consequently decreases. The cations dominate structural dynamics since they are attached to the polymer chains, while the anions are smaller and more mobile ionic species thereby controlling the ionic conductivity. Further interpretation of decoupling of dc conductivity from the segmental relaxation enabled the correlation between polymer morphology and dc conductivity. Supported by the National Science Foundation, Polymers Program.
7 CFR 3022.3 - Inquiry, investigation, and adjudication.
Code of Federal Regulations, 2013 CFR
2013-01-01
... FINANCIAL OFFICER, DEPARTMENT OF AGRICULTURE RESEARCH INSTITUTIONS CONDUCTING USDA-FUNDED EXTRAMURAL... that conducts extramural research funded by USDA bears primary responsibility for prevention and... be separate from those for inquiry and investigation. In most instances, USDA will rely on a research...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Honaker, R.Q.; Reed, S.
1995-12-31
Column flotation provides excellent recovery of ultrafine coal while producing low ash content concentrates. However, column flotation is not efficient for treating fine coal containing significant amounts of mixed-phase particles. Fortunately, enhanced gravity separation has proved to have the ability to treat the mixed-phased particles more effectively. A disadvantage of gravity separation is that ultrafine clay particles are not easily rejected. Thus, a combination of these two technologies may provide a circuit that maximizes both the ash and sulfur rejection that can be achieved by physical coal cleaning while maintaining a high energy recovery. This project is studying the potentialmore » of using different combinations of gravity separators, i.e., a Floatex hydrosizer and a Falcon Concentrator, and a proven flotation column, which will be selected based on previous studies by the principle investigator. During this reporting period, an extensive separation performance comparison between a pilot-scale Floatex Density Separator (18{times}18-inch) and an existing spiral circuit has been conducted at Kerf-McGee Coal Preparation plan for the treatment of nominally {minus}16 mesh coal. The results indicate that the Floatex is a more efficient separation device (E{sub p}=0.12) than a conventional coal spiral (E{sub p}=0.18) for Illinois seam coals. In addition, the treatment of {minus}100 mesh Illinois No. 5 fine coal from the same plant using Falcon concentrator, column flotation (Packed-Column) and their different combinations was also evaluated. For a single operation, both Falcon concentrator and column flotation can produce a clean coal product with 90% combustible recovery and 5% ash content. In the case of the combined circuit, column flotation followed by the Falcon achieved a higher combustible recovery value (about 75%) than that obtained by the individual units while maintaining an ash content less than 3%.« less
Kacenelenbogen, Nadine; Dramaix-Wilmet, Michèle; Schetgen, M; Roland, M
2014-07-22
Analyse the parental behaviours that are recognised as influencing the health of very young children based on family structure (parents separated or not). Cross-sectional study. Free preventive medicine consultations in the French Community of Belgium. Examination of 79 701 infants aged 7-11 months as part of a free preventive medicine consultation. The data came from an assessment conducted 7-11 months after birth during which information was collected, namely about the parents' use of tobacco, the infant's type of nutrition and adherence to vaccination schedules. Parental behaviours: smoking, nutrition and compliance with vaccination schedule. The percentage of infants whose parents were separated was 6.6%. After adjusting for the cultural and socioeconomic environment as well as for other potential confounders, in the event of separation as compared with non-separated parents, the adjusted ORs (95% CI) were as follows: 1.5 (1.3 to 1.7) for the infant's exposure to tobacco; 1.3 (1.2 to 1.4) for total lack of exclusive breast feeding; 1.3 (1.1 to 1.4) and 1.2 (1.1 to 1.2) for breast feeding for a duration of less than 3 and 6 months, respectively; 1.2 (1.1 to 1.4) for non-compliance with the vaccination schedule against rotavirus. The duration of exclusive breast feeding was shorter when parents were separated (p<0.001; median 10 vs 13 weeks). This study reinforces the possibility that parental separation is independently associated with certain parental at-risk behaviours regarding the children's health. This observation should be verified because this could result in major consequences for the work of family doctors, in particular in terms of parent information and targeted prevention. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
An Experimental Investigation of Flow past a Wing at high Angles of Attack
NASA Astrophysics Data System (ADS)
Dalela, Vipul; Mukherjee, Rinku
2017-11-01
The aerodynamic characteristics for post-stall angles of attack past a single and/or multiple 3D wing(s) have been studied using a novel `decambering technique' assuming the flow to be steady. It is expected that the location of separation as well as the strength of the separated flow is unsteady. The objective of this work therefore is to investigate flow at high angles of attack considering unsteady behavior. The numerical technique used for this purpose that accounts for loss in camber due to flow separation is termed as `decambering'. Two linear functions are used to define the `decambering' for the steady case, located at the leading edge and anywhere between 50%-80% chord. Wind tunnel experiments are to be conducted to study the unsteady nature of separated flow using flow visualization techniques. An estimation of the unsteady wake will be of paramount importance. It is expected to get an experimental corroboration for the numerical decambering. A NACA 4415 wing section is being tested for a range of Reynolds numbers. It is observed from the preliminary results that the drag becomes more dominant after increasing the Reynolds number from Re = 0.093 ×106 to Re = 0.128 ×106 resulting a gentle decrease in the lift coefficient, Cl.
Effects-driven chemical fractionation of heavy fuel oil to isolate compounds toxic to trout embryos.
Bornstein, Jason M; Adams, Julie; Hollebone, Bruce; King, Thomas; Hodson, Peter V; Brown, R Stephen
2014-04-01
Heavy fuel oil (HFO) spills account for approximately 60% of ship-source oil spills and are up to 50 times more toxic than medium and light crude oils. Heavy fuel oils contain elevated concentrations of polycyclic aromatic hydrocarbons (PAHs) and alkyl-PAHs, known to be toxic to fish; however, little direct characterization of HFO toxicity has been reported. An effects-driven chemical fractionation was conducted on HFO 7102 to separate compounds with similar chemical and physical properties, including toxicity, to isolate the groups of compounds most toxic to trout embryos. After each separation, toxicity tests directed the next phase of fractionation, and gas chromatography-mass spectrometry analysis correlated composition with toxicity, with a focus on PAHs. Low-temperature vacuum distillation permitted the separation of HFO into 3 fractions based on boiling point ranges. The most toxic of these fractions underwent wax precipitation to remove long-chain n-alkanes. The remaining PAH-rich extract was further separated using open column chromatography, which provided distinct fractions that were grouped according to increasing aromatic ring count. The most toxic of these fractions was richest in PAHs and alkyl-PAHs. The results of the present study were consistent with previous crude oil studies that identified PAH-rich fractions as the most toxic. © 2013 SETAC.
Separation and purification of xenon
Schlea, deceased, Carl Solomon
1978-03-14
Xenon is separated from a mixture of xenon and krypton by extractive distillation using carbon tetrafluoride as the partitioning agent. Krypton is flushed out of the distillation column with CF.sub.4 in the gaseous overhead stream while purified xenon is recovered from the liquid bottoms. The distillation is conducted at about atmospheric pressure or at subatmospheric pressure.
Conduct problems and attention deficit behaviour in middle childhood and cannabis use by age 15.
Fergusson, D M; Lynskey, M T; Horwood, L J
1993-12-01
The relationship between conduct problems and attention deficit behaviours at ages 6, 8, 10 and 12 years and the early onset of cannabis usage by the age of 15 years was studied in a birth cohort of New Zealand children. The analysis showed that while conduct problems during middle childhood were significantly associated with later cannabis use (p < 0.05) there was no association between early attention deficit behaviours and cannabis use (p > 0.40) when the associations between conduct problems and attention deficit behaviours were taken into account. It was estimated that children who showed tendencies to conduct disorder behaviour in middle childhood were between 2.1 to 2.7 times more likely to engage in early cannabis use than children not prone to conduct problems even when a range of factors including family social background, parental separation and parental conflict were taken into account. It is concluded that early conduct disorder behaviours are a risk factor for later cannabis use when due allowance is made for social and contextual factors associated with both early conduct problems and later cannabis use.
NASA Technical Reports Server (NTRS)
Wilcox, Floyd J., Jr.; Pinier, Jeremy T.; Chan, David T.; Crosby, William A.
2016-01-01
A wind-tunnel investigation of a 0.009 scale model of the Space Launch System (SLS) was conducted in the NASA Langley Unitary Plan Wind Tunnel to characterize the aerodynamics of the core and solid rocket boosters (SRBs) during booster separation. High-pressure air was used to simulate plumes from the booster separation motors (BSMs) located on the nose and aft skirt of the SRBs. Force and moment data were acquired on the core and SRBs. These data were used to corroborate computational fluid dynamics (CFD) calculations that were used in developing a booster separation database. The SRBs could be remotely positioned in the x-, y-, and z-direction relative to the core. Data were acquired continuously while the SRBs were moved in the axial direction. The primary parameters varied during the test were: core pitch angle; SRB pitch and yaw angles; SRB nose x-, y-, and z-position relative to the core; and BSM plenum pressure. The test was conducted at a free-stream Mach number of 4.25 and a unit Reynolds number of 1.5 million per foot.
Nielson, Elizabeth M.; May, Darrick G.; Forcehimes, Alyssa A.; Bogenschutz, Michael P.
2018-01-01
Research on the clinical applications of psychedelic-assisted psychotherapy has demonstrated promising early results for treatment of alcohol dependence. Detailed description of the content and methods of psychedelic-assisted psychotherapy, as it is conducted in clinical settings, is scarce. Methods: An open-label pilot (proof-of-concept) study of psilocybin-assisted treatment of alcohol dependence (NCT01534494) was conducted to generate data for a phase 2 RCT (NCT02061293) of a similar treatment in a larger population. The present paper presents a qualitative content analysis of the 17 debriefing sessions conducted in the pilot study, which occurred the day after corresponding psilocybin medication sessions. Results: Participants articulated a series of key phenomena related to change in drinking outcomes and acute subjective effects of psilocybin. Discussion: The data illuminate change processes in patients' own words during clinical sessions, shedding light on potential therapeutic mechanisms of change and how participants express effects of psilocybin. This study is unique in analyzing actual clinical sessions, as opposed to interviews of patients conducted separately from treatment. PMID:29515449
Study of physical and sound absorbing property of epoxy blended coir dust biocomposite
NASA Astrophysics Data System (ADS)
Nath, G.; Mishra, S. P.
2016-09-01
Reinforcement biocomposite has gained more attention recently due to its low cost, abundantly availability, low density, specific properties, easy method of separation, enhanced energy recovery, CO2 neutrality, biodegradability and recyclable in nature. As a waste product of coconut fruit, the coconut coir dust (CCD) obtained from the coconut husk. The biocomposite material prepared from the CCD modified with the proper blended solution with the help of ultrasonic technique. The study of adiabatic compressibility of acetone / water (70/30) worth its blending property for bleaching of CCD. The biocomposite material of CCD was prepared with epoxy resin. The different physical properties such as sound absorption coefficient, thermal conductivity and electrical conductivity were measured. The morphological study of biocomposite and measurement of sound absorption coefficient shows good evidence of sound absorbing characteristics of biocomposite of CCD. The sound absorption property of composite material shows a significant result where as the thermal conductivity and electrical conductivity executes a weak result. Thus biocomposite of CCD can acts as a good sound absorber and band conductor of heat and electric current.
Fluids Density Functional Theory of Salt-Doped Block Copolymers
NASA Astrophysics Data System (ADS)
Brown, Jonathan R.; Hall, Lisa M.
Block copolymers have attracted a great deal of recent interest as potential non-flammable, solid-state, electrolyte materials for batteries or other charge carrying applications. The microphase separation in block copolymers combines the properties of a conductive (though mechanically soft) polymer with a mechanically robust (though non-conductive) polymer. We use fluids density functional theory (fDFT) to study the phase behavior of salt-doped block copolymers. Because the salt prefers to preferentially solvate into the conductive phase, salt doping effectively enhances the segregation strength between the two polymer types. We consider the effects of this preferential solvation and of charge correlations by separately modeling the ion-rich phase, without bonding, using the Ornstein-Zernike equation and the hypernetted-chain closure. We use the correlations from this subsystem in the inhomogeneous fDFT calculations. Initial addition of salt increases the domain spacing and sharpens the interfacial region, but for high salt loadings the interface can broaden. Addition of salt can also drive a system with a low copolymer segregation strength to order by first passing through a two phase regime with a salt-rich ordered phase and a salt-poor disordered phase. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award Number DE-SC0014209.
Gamma Ray Spectroscopy and SASSYER
NASA Astrophysics Data System (ADS)
Pauerstein, Benjamin; Bonniwell, Cain; Allmond, J. M.; Beausang, C. W.
2009-10-01
An experiment was performed to study the Gd and Tb nuclei resulting from a 27 MeV proton beam on a 156Gd target. This was conducted at Lawrence Berkeley National Laboratory using the STARS/LIBERACE array. The main focus of the experiment was on charged particle channels (p,d) into 155Gd and (p,t) into 154Gd. However, the trigger was either gamma-gamma or particle-gamma so new data was also obtained on 155Tb nuclei following fusion evaporation reactions. Preliminary analysis was conducted at Wright Nuclear Structure Lab where RADWARE programs were used to analyze the data and search for unknown gamma rays. A second, separate, experiment was conducted using the SASSYER (a gas-filled separator at Yale). In this experiment, fission fragments from a 252Cf source were focused to a DSSD and a Ge detector was used to search for either gamma-decay from long lived isomers in the fission fragments or to find gammas from recoil-beta-decay tagging on the fission fragments. The data collection seems to have gone smoothly, and the data is currently being sorted for analysis. This work was supported by the US Department of Energy under grant numbers DE-FG02-52NA26206 and DE-FG02-05ER41379.
When Parents Ask ... about Preterm Birth, Breastfeeding Success, Breast Cancer, or Waterbirth.
Moore, Mary Lou
2003-01-01
IN THIS COLUMN, THE AUTHOR REVIEWS RESEARCH ON FOUR SEPARATE TOPICS: the prevention of preterm birth, the effect of epidurals on breastfeeding success, the possible protective effect of lactation on breast cancer, and laboring in water. In two separate studies-a multisite study in the United States and a second study from Brazil-natural progesterone was shown to significantly reduce the incidence of preterm birth in women at high risk. A third study conducted in the United Kingdom examined the effect of clindamycin on preventing infection that can lead to preterm birth. A group of studies related to lactation found that early breastfeeding was more successful in women who did not have epidural anesthesia. In a Korean study, the lifetime duration of breastfeeding was associated with a significant reduction in breast cancer. Concerning waterbirth, Swiss researchers found that, when a woman labored in water, she regulated both water temperature and bathing duration to ensure that her body temperature and that of the fetus remained within a normal physiological range.
Jiang, Wu; Jia, Li; Zhen-Ming, Xu
2009-01-15
The electrostatic separation is an effective method for recycling waste electrical and electronic equipment (WEEE). The efficiency of electrostatic separation processes depends on the ability of the separator. As a classical one, the roll-type corona-electrostatic separator has some advantages in recycling metals and plastics from waste printed circuit board (PCB). However, its industry application still faces some problems, such as: the further disposal of the middling products of the separation process; the balance of the production capacity and the good separation efficiency; the separation of the fine granular mixture and the stability of the separation process. A new "two-roll-type corona-electrostatic separator" was built to overcome the limitation of the classical one. The experimental data were discussed and the results showed that the outcome of the separation process was improved by using the new separator. Compared with the classical machine, the mass of conductive products increases 8.9% (groups 2 and 3) and10.2% (group 4) while the mass of the middling products decreases 45% (groups 2 and 3) and 31.7% (group 4), respectively. The production capacity of the new machine increases, and the stability of the separation process is enhanced.
Ionomers for Ion-Conducting Energy Materials
NASA Astrophysics Data System (ADS)
Colby, Ralph
For ionic actuators and battery separators, it is vital to utilize single-ion conducting ionomers that avoid the detrimental polarization of other ions. Single-ion conducting ionomers are synthesized based on DFT calculations, with low glass transition temperatures (facile dynamics) to prepare ion-conducting membranes for battery separators that conduct Li+ or Na+. Characterization by X-ray scattering, dielectric spectroscopy, FTIR, NMR and linear viscoelasticity collectively develop a coherent picture of ionic aggregation and both counterion and polymer dynamics. 7Li NMR diffusion measurements find that diffusion is faster than expected by conductivity using the Nernst-Einstein equation, which means that the majority of Li diffusion occurs by ion pairs moving with the polymer segmental motion. Segmental motion only contributes to ionic conduction in the rare event that one of these ion pairs has an extra Li (a positive triple ion). This leads us to a new metric for ion-conducting soft materials, the product of the cation number density p0 and their diffusion coefficient D; p0D is the diffusive flux of lithium ions. This new metric has a maximum at intermediate ion content that corresponds to the overlap of ion pair polarizability volumes. At higher ion contents, the ion pairs interact strongly and form larger aggregation states that retard segmental motion of both mobile ion pairs and triple ions.
Martin, Linda; Miranda, Baldwin; Bean, Michelle
2008-01-01
The main objective of the present study was to explore the impact of separation on couples where one spouse lives in a skilled nursing facility and the other spouse lives alone in the community. Six couples participated in a 10-week gardening group. Semi-structured interviews were conducted at the beginning of the study and observations were made and discussions engaged through the 10-week horticultural programme. Thematic analysis of interviews and discussions revealed reduced social participation of community-dwelling spouses in an effort to maintain their marital role. In one or more cases the non-institutionalized spouse adapted to separation by developing social roles and relationships within the skilled nursing facility and continuing as a caregiver to their spouse. Occupational therapists are encouraged to include spouses in programmes to nurture healthy spousal roles. Further research is needed to explore how elderly couples may support each other through purposeful occupation while one spouse is in a long-term care facility. (c) 2007 John Wiley & Sons, Ltd.
Clusius-Dickel Separations (CDS): A new look at an old technique
NASA Technical Reports Server (NTRS)
Grodzka, P. G.
1975-01-01
The history, applications, and theoretical basis of the CDS technique are reviewed. The advantage to be realized by conduction of CDSs in low-g, space environments are deduced. The results are reported of investigations aimed at further improving CDS efficiencies by altering convective flow patterns. The question of whether multicellular flow or turbulence can introduce a new separation mechanism which would boost separation efficiencies at least an order of magnitude is considered. Results are presented and discussed.
Electrohydrodynamic effects in continuous flow electrophoresis
NASA Technical Reports Server (NTRS)
Rhodes, P. H.; Snyder, R. S.; Roberts, G. O.; Baygents, J. C.
1991-01-01
We demonstrate experimentally and theoretically the importance of electrohydrodynamic (EHD) flows in continuous-flow electrophoresis (CFE) separations. These flows are associated with variations in the conductivity or dielectric constant, and are quadratic in the field strength. They appear to be the main cause of extraneous and undesired flows in CFE which have degraded separation performance and have until now not been explained. We discuss the importance of EHD flows relative to other effects. We also describe possible techniques for reducing the associated degradation of CFE separations.
Dieleman, Gwendolyn C; Huizink, Anja C; Tulen, Joke H M; Utens, Elisabeth M W J; Creemers, Hanneke E; van der Ende, Jan; Verhulst, Frank C
2015-01-01
It is of debate whether or not childhood anxiety disorders (AD) can be captured by one taxonomic construct. This study examined whether perceived arousal (PA), autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis measures can distinguish children with different primary diagnoses of clinical anxiety disorders (AD) from each other, and from a general population reference group (GP). The study sample consisted of 152 AD children (comparing separation anxiety disorder, generalized anxiety disorder, social phobia and specific phobia), aged 8- to 12-years, and 200 same-aged reference children. HPA-axis functioning was measured by a diurnal cortisol profile. ANS functioning was measured by continuous measures of skin conductance level in rest and during a mental arithmetic task and high frequency heart rate variability in rest. PA was assessed by a questionnaire. The AD sample showed lower high frequency heart rate variability during rest, heightened anticipatory PA, higher basal and reactive skin conductance levels and lower basal HPA-axis functioning compared to the GP sample. The existence of three or more clinical disorders, i.e. a high clinical 'load', was associated with lower basal HPA-axis functioning, higher skin conductance level and lower posttest PA. Specific phobia could be discerned from social phobia and separation anxiety disorder on higher skin conductance level. Our findings indicated that children with AD have specific psychophysiological characteristics, which resemble the psychophysiological characteristics of chronic stress. A high clinical 'load' is associated with an altered ANS and HPA-axis functioning. Overall, ANS and HPA-axis functioning relate to AD in general, accept for specific phobia. Copyright © 2014 Elsevier Ltd. All rights reserved.
Huie, Matthew M; DiLeo, Roberta A; Marschilok, Amy C; Takeuchi, Kenneth J; Takeuchi, Esther S
2015-06-10
Batteries are multicomponent systems where the theoretical voltage and stoichiometric electron transfer are defined by the electrochemically active anode and cathode materials. While the electrolyte may not be considered in stoichiometric electron-transfer calculations, it can be a critical factor determining the deliverable energy content of a battery, depending also on the use conditions. The development of ionic liquid (IL)-based electrolytes has been a research area of recent reports by other researchers, due, in part, to opportunities for an expanded high-voltage operating window and improved safety through the reduction of flammable solvent content. The study reported here encompasses a systematic investigation of the physical properties of IL-based hybrid electrolytes including quantitative characterization of the electrolyte-separator interface via contact-angle measurements. An inverse trend in the conductivity and wetting properties was observed for a series of IL-based electrolyte candidates. Test-cell measurements were undertaken to evaluate the electrolyte performance in the presence of functioning anode and cathode materials, where several promising IL-based hybrid electrolytes with performance comparable to that of conventional carbonate electrolytes were identified. The study revealed that the contact angle influenced the performance more significantly than the conductivity because the cells containing IL-tetrafluoroborate-based electrolytes with higher conductivity but poorer wetting showed significantly decreased performance relative to the cells containing IL-bis(trifluoromethanesulfonyl)imide electrolytes with lower conductivity but improved wetting properties. This work contributes to the development of new IL battery-based electrolyte systems with the potential to improve the deliverable energy content as well as safety of lithium-ion battery systems.
A hierarchical word-merging algorithm with class separability measure.
Wang, Lei; Zhou, Luping; Shen, Chunhua; Liu, Lingqiao; Liu, Huan
2014-03-01
In image recognition with the bag-of-features model, a small-sized visual codebook is usually preferred to obtain a low-dimensional histogram representation and high computational efficiency. Such a visual codebook has to be discriminative enough to achieve excellent recognition performance. To create a compact and discriminative codebook, in this paper we propose to merge the visual words in a large-sized initial codebook by maximally preserving class separability. We first show that this results in a difficult optimization problem. To deal with this situation, we devise a suboptimal but very efficient hierarchical word-merging algorithm, which optimally merges two words at each level of the hierarchy. By exploiting the characteristics of the class separability measure and designing a novel indexing structure, the proposed algorithm can hierarchically merge 10,000 visual words down to two words in merely 90 seconds. Also, to show the properties of the proposed algorithm and reveal its advantages, we conduct detailed theoretical analysis to compare it with another hierarchical word-merging algorithm that maximally preserves mutual information, obtaining interesting findings. Experimental studies are conducted to verify the effectiveness of the proposed algorithm on multiple benchmark data sets. As shown, it can efficiently produce more compact and discriminative codebooks than the state-of-the-art hierarchical word-merging algorithms, especially when the size of the codebook is significantly reduced.
Huang, Rongfu; Chen, Yuan; Gamal El-Din, Mohamed
2016-06-21
The separation of classical, aromatic, oxidized, and heteroatomic (sulfur-containing) naphthenic acid (NA) species from unprocessed and ozone-treated oil sands process-affected water (OSPW) was performed using silver-ion (Ag-ion) solid phase extraction (SPE) without the requirement of pre-methylation for NAs. OSPW samples before SPE and SPE fractions were characterized using ultra performance liquid chromatography ion mobility time-of-flight mass spectrometry (UPLC-IM-TOFMS) to corroborate the separation of distinct NA species. The mass spectrum identification applied a mass tolerance of ±1.5 mDa due to the mass errors of NAs were measured within this range, allowing the identification of O2S-NAs from O2-NAs. Moreover, separated NA species facilitated the tandem mass spectrometry (MS/MS) characterization of NA compounds due to the removal of matrix and a simplified composition. MS/MS results showed that classical, aromatic, oxidized, and sulfur-containing NA compounds were eluted into individual SPE fractions. Overall results indicated that the separation of NA species using Ag-ion SPE is a valuable method for extracting individual NA species that are of great interest for environmental toxicology and wastewater treatment research, to conduct species-specific studies. Furthermore, the separated NA species on the milligram level could be widely used as the standard materials for environmental monitoring of NAs from various contamination sites.
Effect of interstitial palladium on plasmon-driven charge transfer in nanoparticle dimers.
Lerch, Sarah; Reinhard, Björn M
2018-04-23
Capacitive plasmon coupling between noble metal nanoparticles (NPs) is characterized by an increasing red-shift of the bonding dipolar plasmon mode (BDP) in the classical electromagnetic coupling regime. This model breaks down at short separations where plasmon-driven charge transfer induces a gap current between the NPs with a magnitude and separation dependence that can be modulated if molecules are present in the gap. Here, we use gap contained DNA as a scaffold for the growth of palladium (Pd) NPs in the gap between two gold NPs and investigate the effect of increasing Pd NP concentration on the BDP mode. Consistent with enhanced plasmon-driven charge transfer, the integration of discrete Pd NPs depolarizes the capacitive BDP mode over longer interparticle separations than is possible in only DNA-linked Au NPs. High Pd NP densities in the gap increases the gap conductance and induces the transition from capacitive to conductive coupling.
Tegegne, Awoke Seyoum; Ndlovu, Principal; Zewotir, Temesgen
2018-04-27
HIV has the most serious effects in Sub-Saharan African countries as compared to countries in other parts of the world. As part of these countries, Ethiopia has been affected significantly by the disease, and the burden of the disease has become worst in the Amhara Region, one of the eleven regions of the country. Being a defaulter or dropout of HIV patients from the treatment plays a significant role in treatment failure. The current research was conducted with the objective of comparing the performance of the joint and the separate modelling approaches in determining important factors that affect HIV patients' longitudinal CD4 cell count change and time to default from treatment. Longitudinal data was obtained from the records of 792 HIV adult patients at Felege-Hiwot Teaching and Specialized Hospital in Ethiopia. Two alternative approaches, namely separate and joint modeling data analyses, were conducted in the current study. Joint modeling was conducted for an analysis of the change of CD4 cell count and the time to default in the treatment. In the joint model, a generalized linear mixed effects model and Weibul survival sub-models were combined together for the repetitive measures of the CD4 cell count change and the number of follow-ups in which patients wait in the treatment. Finally, the two models were linked through their shared unobserved random effects using a shared parameter model. Both separate and joint modeling approach revealed a consistent result. However, the joint modeling approach was more parsimonious and fitted the given data well as compared to the separate one. Age, baseline CD4 cell count, marital status, sex, ownership of cell phone, adherence to HAART, disclosure of the disease and the number of follow-ups were important predictors for both the fluctuation of CD4 cell count and the time-to default from treatment. The inclusion of patient-specific variations in the analyses of the two outcomes improved the model significantly. Certain groups of patients were identified in the current investigation. The groups already identified had high fluctuation in the number of CD4 cell count and defaulted from HAART without any convincing reasons. Such patients need high intervention to adhere to the prescribed medication.
NASA Astrophysics Data System (ADS)
Chung, T. W.; Chen, C. K.; Hsu, S. H.
2017-11-01
Protein concentration process using filter membrane has a significant advantage on energy saving compared to the traditional drying processes. However, fouling on large membrane area and frequent membrane cleaning will increase the energy consumption and operation cost for the protein concentration process with filter membrane. In this study, the membrane filtration for protein concentration will be conducted and compared with the recent protein concentration technology. The analysis of operating factors for protein concentration process using filter membrane was discussed. The separation mechanism of membrane filtration was developed according to the size difference between the pore of membrane and the particle of filter material. The Darcy’s Law was applied to discuss the interaction on flux, TMP (transmembrane pressure) and resistance in this study. The effect of membrane pore size, pH value and TMP on the steady-state flux (Jst) and protein rejection (R) were studied. It is observed that the Jst increases with decreasing membrane pore size, the Jst increases with increasing TMP, and R increased with decreasing solution pH value. Compare to other variables, the pH value is the most significant variable for separation between protein and water.
Numerical Study on Density Gradient Carbon-Carbon Composite for Vertical Launching System
NASA Astrophysics Data System (ADS)
Yoon, Jin-Young; Kim, Chun-Gon; Lim, Juhwan
2018-04-01
This study presents new carbon-carbon (C/C) composite that has a density gradient within single material, and estimates its heat conduction performance by a numerical method. To address the high heat conduction of a high-density C/C, which can cause adhesion separation in the steel structures of vertical launching systems, density gradient carbon-carbon (DGCC) composite is proposed due to its exhibiting low thermal conductivity as well as excellent ablative resistance. DGCC is manufactured by hybridizing two different carbonization processes into a single carbon preform. One part exhibits a low density using phenolic resin carbonization to reduce heat conduction, and the other exhibits a high density using thermal gradient-chemical vapor infiltration for excellent ablative resistance. Numerical analysis for DGCC is performed with a heat conduction problem, and internal temperature distributions are estimated by the forward finite difference method. Material properties of the transition density layer, which is inevitably formed during DGCC manufacturing, are assumed to a combination of two density layers for numerical analysis. By comparing numerical results with experimental data, we validate that DGCC exhibits a low thermal conductivity, and it can serve as highly effective ablative material for vertical launching systems.
Xu, Xiaohui Sophia; Dueker, Stephen R; Christopher, Lisa J; Lohstroh, Pete N; Keung, Chi Fung Anther; Cao, Kai Kevin; Bonacorsi, Samuel J; Cojocaru, Laura; Shen, Jim X; Humphreys, W Griffith; Stouffer, Bruce; Arnold, Mark E
2012-08-01
An absolute bioavailability study that utilized an intravenous [(14)C]microdose was conducted for saxagliptin (Onglyza(®)), a marketed drug product for the treatment of Type 2 diabetes mellitus. Concentrations of [(14)C]saxagliptin were determined by accelerator MS (AMS) after protein precipitation, chromatographic separation by UPLC and analyte fraction collection. A series of investigative experiments were conducted to maximize the release of the drug from high-affinity receptors and nonspecific adsorption, and to determine a suitable quantitation range. A technique-appropriate validation demonstrated the accuracy, precision, specificity, stability and recovery of the AMS methodology across the concentration range of 0.025 to 15.0 dpm/ml (disintegration per minute per milliliter), the equivalent of 1.91-1144 pg/ml. Based on the study sample analysis, the mean absolute bioavailability of saxagliptin was 50% in the eight subjects with a CV of 6.6%. Incurred sample reanalysis data fell well within acceptable limits. This study demonstrated that the optimized sample pretreatment and chromatographic separation procedures were critical for the successful implementation of an UPLC plus AMS method for [(14)C]saxagliptin. The use of multiple-point standards are useful, particularly during method development and validation, to evaluate and correct for concentration-dependent recovery, if observed, and to monitor and control process loss and operational variations.
A new approach to isolating siderophore-producing actinobacteria.
Nakouti, I; Sihanonth, P; Hobbs, G
2012-07-01
This study was conducted to investigate the application of 2,2'-dipyridyl as a new approach to isolating siderophore-producing actinobacteria. Isolation of actinobacteria from soil was conducted by a soil dilution plate technique using starch-casein agar. Iron starvation was fostered by the incorporation of the iron chelator 2,2'-dipyridyl in the isolation medium. Pretreatment of the samples at an elevated temperature (40°C) ensured that the majority of nonsporulating bacteria were excluded. The survivors of this treatment were largely actinobacteria. Of the viable cultures grown in the presence of 2,2'-dipyridyl, more than 78-88% (average of three separate studies) were reported to produce siderophore-like compounds compared to 13-18% (average of three separate studies) when grown on the basic media in the absence of the chelating agent. The most prolific producers as assessed by the chrome azurol sulphate (CAS) assay were further characterized and found to belong to the genus Streptomyces. Selective pressure using 2,2'-dipyridyl as an iron-chelating agent in starch-casein media increased the isolation of siderophore-producing actinobacteria compared to the unamended medium. The study described represents a new approach to the isolation of siderophore-producing actinobacteria using a novel procedure that places a selection on cell population based upon the incorporation of a chelating agent in the medium. © 2012 The Authors. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.
41 CFR 60-300.81 - Access to records.
Code of Federal Regulations, 2014 CFR
2014-07-01
... REGARDING DISABLED VETERANS, RECENTLY SEPARATED VETERANS, ACTIVE DUTY WARTIME OR CAMPAIGN BADGE VETERANS... conducting on-site compliance evaluations and complaint investigations and inspecting and copying such books... provide OFCCP access to these materials, including electronic records, off-site for purposes of conducting...
The first dedicated life sciences Spacelab mission
NASA Technical Reports Server (NTRS)
Perry, T. W.; Rummel, J. A.; Griffiths, L. D.; White, R. J.; Leonard, J. I.
1984-01-01
JIt is pointed out that the Shuttle-borne Spacelab provides the capability to fly large numbers of life sciences experiments, to retrieve and rescue experimental equipment, and to undertake multiple-flight studies. A NASA Life Sciences Flight Experiments Program has been organized with the aim to take full advantages of this capability. A description is provided of the scientific aspects of the most ambitious Spacelab mission currently being conducted in connection with this program, taking into account the First Dedicated Life Sciences Spacelab Mission. The payload of this mission will contain the equipment for 24 separate investigations. It is planned to perform the mission on two separate seven-day Spacelab flights, the first of which is currently scheduled for early 1986. Some of the mission objectives are related to the study of human and animal responses which occur promptly upon achieving weightlessness.
ERIC Educational Resources Information Center
Wootten, Marian; And Others
Separate formal evaluations were conducted of the following alternative schools in the Seattle Public Schools system: Nova, Orca, Summit K-12, Alternative School 1 (AS1), Alternative Elementary School II (AES II), and Alternative Elementary School III (AES III). These six documents, combined here as one item, describe the distinctive…
Volunteering, income and health.
Detollenaere, Jens; Willems, Sara; Baert, Stijn
2017-01-01
Separate literatures have related volunteering to health gains and income gains. We study the association between volunteering, income and health within one statistical framework. A state-of-the-art mediation analysis is conducted on data concerning the health, volunteering and sociodemographic characteristics of 42926 individuals within 29 European countries. We find that volunteering is positively associated to self-rated health. This association is partially mediated by household income.
Volunteering, income and health
Detollenaere, Jens; Willems, Sara
2017-01-01
Separate literatures have related volunteering to health gains and income gains. We study the association between volunteering, income and health within one statistical framework. A state-of-the-art mediation analysis is conducted on data concerning the health, volunteering and sociodemographic characteristics of 42926 individuals within 29 European countries. We find that volunteering is positively associated to self-rated health. This association is partially mediated by household income. PMID:28273163
ERIC Educational Resources Information Center
Keiffer, Elizabeth Ann
2011-01-01
A differential item functioning (DIF) simulation study was conducted to explore the type and level of impact that contamination had on type I error and power rates in DIF analyses when the suspect item favored the same or opposite group as the DIF items in the matching subtest. Type I error and power rates were displayed separately for the…
ERIC Educational Resources Information Center
Tirosh, Dina; Stavy, Ruth
A study was conducted in Israel to determine effects of external similarity in problem structure on students' responses. Fifty students from each of the 7th, 8th, 10th, and 12th grade levels were presented with three problems involving successive divisions that were similar in structure. The problems asked separately whether the processes of…
Robert Becker; William Gates; Bernard J. Niemann Jr.
1979-01-01
This paper provides an overview of methods and results obtained from an extensive social and recreational carrying capacity study conducted for a National Scenic and Recreational Riverway - the Lower St. Croix. The paper also includes preliminary results and illustrations of a cognitive mapping technique for mapping scenic beauty. Over 1000 separate polygons were...