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Sample records for btp supported liquid

  1. Selective recovery of minor trivalent actinides from high level liquid waste by R-BTP/SiO2-P adsorbents

    NASA Astrophysics Data System (ADS)

    Sano, Yuichi; Surugaya, Naoki; Yamamoto, Masahiko

    2010-03-01

    Concerning the selective recovery of minor trivalent actinides (MA(III) = Am(III) and Cm(III)) from high level liquid waste (HLLW) by extraction chromatography, adsorption and elution behaviours of MA(III) and fission products (FP) in a nitric acid media were studied using iHex-BTP/SiO2-P adsorbents, which is expected to show high adsorption affinity for MA(III) even in concentrated HNO3 solution, such as HLLW. In the batch experiments, Pd showed strong adsorption on iHex-BTP/SiO2-P adsorbents under any concentration of HNO3. The MA(III) and heavy Ln(III) (Sm(III), Eu(III) and Gd(III)) were also adsorbed at the condition of high HNO3 concentration, but they showed no adsorption under low HNO3concentration. The separation factor for MA(III)/heavy Ln(III) took the maximum value (over 100) at around 1mol/dm3 HNO3. It was difficult to elute MA(III) or heavy Ln(III) selectively by HNO3 from the iHex-BTP/SiO2-P adsorbents degradated by ?-ray irradiation. The chromatographic separation of real HLLW by an iHex-BTP/SiO2-P column showed that MA(III) could be recovered selectively by adjusting the acidity of the feed solution, i.e. HLLW, to 1mol/dm3 and using H2O as eluant. The adsorption of Pd(II) can be decreased by the addition of appropriate complexing reagents, e.g. DTPA, into HLLW without any effects on the MA(III) adsorption.

  2. Supported liquid membrane electrochemical separators

    DOEpatents

    Pemsler, J. Paul (Lexington, MA); Dempsey, Michael D. (Revere, MA)

    1986-01-01

    Supported liquid membrane separators improve the flexibility, efficiency and service life of electrochemical cells for a variety of applications. In the field of electrochemical storage, an alkaline secondary battery with improved service life is described in which a supported liquid membrane is interposed between the positive and negative electrodes. The supported liquid membranes of this invention can be used in energy production and storage systems, electrosynthesis systems, and in systems for the electrowinning and electrorefining of metals.

  3. A comparative study of some BTP and BTBP class ligands

    SciTech Connect

    Retegan, T.; Fermvik, A.; Skarnemark, G.; Ekberg, C.; Foreman, M.R. St J.

    2008-07-01

    Partitioning and transmutation (P and T) of the long lived nuclides in spent nuclear fuel into short-lived ones is an important step in decreasing the radiotoxicity, volume, and time necessary for storage in a repository. A proper separation of the metals used in the transmutation process is necessary and solvent extraction with different ligands is one of the possibilities. This separation has been extensively tested in Europe using the BTP and BTBP class ligands. In this paper a comparative study of the extraction capabilities of CyMe{sub 4}-BTP and CyMe{sub 4}-BTBP as function of different diluents and kinetics has been made. (authors)

  4. Method of fabrication of supported liquid membranes

    SciTech Connect

    Luebke, David R.; Hong, Lei; Myers, Christina R.

    2015-11-17

    Method for the fabrication of a supported liquid membrane having a dense layer in contact with a porous layer, and a membrane liquid layer within the interconnected pores of the porous layer. The dense layer is comprised of a solidified material having an average pore size less than or equal to about 0.1 nanometer, while the porous layer is comprised of a plurality of interconnected pores and has an average pore size greater than 10 nanometers. The supported liquid membrane is fabricated through the preparation of a casting solution of a membrane liquid and a volatile solvent. A pressure difference is established across the dense layer and porous layer, the casting solution is applied to the porous layer, and the low viscosity casting solution is drawn toward the dense layer. The volatile solvent is evaporated and the membrane liquid precipitates, generating a membrane liquid layer in close proximity to the dense layer.

  5. Separation of metals by supported liquid membranes

    SciTech Connect

    Takigawa, D.Y.

    1990-12-31

    A supported liquid membrane system for the separation of a preselected chemical species within a feedstream, preferably an aqueous feedstream, includes a feed compartment containing a feed solution having at least one preselected chemical species therein, a stripping compartment containing a stripping solution therein, and a microporous polybenzimidazole membrane situated between the compartments, the microporous polybenzimidazole membrane containing an extractant mixture selective for the preselected chemical species within the membrane pores is disclosed along with a method of separating preselected chemical species from a feedstream with such a system, and a supported liquid membrane for use in such a system.

  6. Flexible Support Liquid Argon Heat Intercept

    SciTech Connect

    Rudland, D.L.; /Fermilab

    1987-05-18

    A device in the flexible support system for the Central Calorimeter is the Liquid Argon Heat Intercept. The purpose of this apparatus is to intercept heat outside the inner vessel so that bubbles do not form inside. If bubbles did happen to form inside the vessel, they would cause an electric arc between the read-out board and the absorption plates, thus destroying the pre-amplifier. Since this heat intercept is located in the center of the flexible support, it must also support the load of the Central Caloimeter. Figure 1 shows how the intercept works. The subcooled liquid argon is driven through a 1/4-inch x 0.049-inch w tube by hydrostatic pressure. the ambient heat boils the subcooled argon. The gaseous argon flows through the tube and is condensed at the top of the vessel by a 100 kW cooling coil. This process is rpesent in all four flexible support systems.

  7. Separations by supported liquid membrane cascades

    DOEpatents

    Danesi, P.R.

    1983-09-01

    The invention describes a new separation technique which leads to multi-stage operations by the use of a series (a cascade) of alternated carrier-containing supported-liquid cation exchanger extractant and a liquid anion exchanger extractant (or a neutral extractant) as carrier. The membranes are spaced between alternated aqueous electrolytic solutions of different composition which alternatively provide positively charged extractable species and negatively charged (or zero charged) extractable species, of the chemical species to be separated. The alternated aqueous electrolytic solutions in addition to providing the driving force to the process, simultaneously function as a stripping solution from one type of membrane and as an extraction-promoting solution for the other type of membrane. The aqueous electrolytic solution and the supported liquid membranes are arranged to provide a continuous process.

  8. Support-free pulsed liquid-liquid chromatography.

    PubMed

    Kostanyan, Artak E; Voshkin, Andrei A

    2009-11-01

    A simple technique of support-free liquid-liquid chromatography is suggested that operates without incorporation of a centrifuge. The pulsed chromatography apparatus consists of a stationary coiled tube and a pulsation device to produce reciprocating motion of liquid phases within each individual coil segment. This reciprocating motion generates a centrifugal force field varying in intensity and direction that leads to an improved mixing of the two liquid phases and retains the stationary phase in the coiled tubing. The intensity of the back and forth motion of liquid phases within each coil unit can be varied by varying the frequency and/or the amplitude of the pulsations generated by the pulsation device. As the magnitude of the stationary phase retention is of paramount importance for success of the technique, the retention of the stationary phase in the pulsed coil column was experimentally studied. A few experiments were conducted to test the chromatographic behavior of valeric (n-pentanoic) and caproic (n-hexanoic) acids. The results obtained demonstrate the potential of the new separation method for preparative purposes. PMID:19758594

  9. Separations by supported liquid membrane cascades

    DOEpatents

    Danesi, Pier R. (Clarendon Hills, IL)

    1986-01-01

    The invention describes a new separation technique which leads to multi-stage operations by the use of a series (a cascade) of alternated carrier-containing supported-liquid membranes. The membranes contain alternatively a liquid cation exchanger extractant and a liquid anion exchanger extractant (or a neutral extractant) as carrier. The membranes are spaced between alternated aqueous electrolytic solutions of different composition which alternatively provide positively charged extractable species and negatively charged (or zero charged) extractable species, of the chemical species to be separated. The alternated aqueous electrolytic solutions in addition to providing the driving force to the process, simultaneously function as a stripping solution from one type of membrane and as an extraction-promoting solution for the other type of membrane. The aqueous electrolytic solutions and the supported liquid membranes are arranged in such a way to provide a continuous process which leads to the continuous enrichment of the species which show the highest permeability coefficients. By virtue of the very high number of stages which can be arranged, even chemical species having very similar chemical behavior (and consequently very similar permeability coefficients) can be completely separated. The invention also provide a way to concentrate the separated species.

  10. BtpB, a novel Brucella TIR-containing effector protein with immune modulatory functions

    PubMed Central

    Salcedo, Suzana P.; Marchesini, Mara I.; Degos, Clara; Terwagne, Matthieu; Von Bargen, Kristine; Lepidi, Hubert; Herrmann, Claudia K.; Santos Lacerda, Thais L.; Imbert, Paul R. C.; Pierre, Philippe; Alexopoulou, Lena; Letesson, Jean-Jacques; Comerci, Diego J.; Gorvel, Jean-Pierre

    2013-01-01

    Several bacterial pathogens have TIR domain-containing proteins that contribute to their pathogenesis. We identified a second TIR-containing protein in Brucella spp. that we have designated BtpB. We show it is a potent inhibitor of TLR signaling, probably via MyD88. BtpB is a novel Brucella effector that is translocated into host cells and interferes with activation of dendritic cells. In vivo mouse studies revealed that BtpB is contributing to virulence and control of local inflammatory responses with relevance in the establishment of chronic brucellosis. Together, our results show that BtpB is a novel Brucella effector that plays a major role in the modulation of host innate immune response during infection. PMID:23847770

  11. A remarkable enhancement in Am?/Eu? selectivity by an ionic liquid based solvent containing bis-1,2,4-triazinyl pyridine derivatives: DFT validation of experimental results.

    PubMed

    Bhattacharyya, Arunasis; Ansari, Seraj A; Gadly, Trilochan; Ghosh, Sunil K; Mohapatra, Manoj; Mohapatra, P K

    2015-04-01

    Mutual separation of trivalent actinide (An(3+)) and lanthanide (Ln(3+)) using several soft (N) donor ligands (bis(5,6-dialkyl-1,2,4-triazinyl)pyridine (R-BTP)) is attempted for the first time in room temperature ionic liquid (RTIL) medium. The results indicate a spectacular enhancement in the selectivity as compared to that in molecular diluents with a separation factor (S.F.) of >3000 for Am(3+) over Eu(3+) using the methyl derivative (Me-BTP) in RTIL medium using [C(n)mim][NTf2] as the diluents (where n = 2, 3, 4, 6 or 8). Such a high S.F. value has never been reported before with any of the R-BTP derivatives in molecular diluents. An opposite trend in the distribution ratio values of both Am(3+) and Eu(3+) with the increasing size of the alkyl (R) group is observed in RTIL medium when compared with that in molecular diluents. The differences in the extraction behaviour of R-BTPs in RTILs vis--vis molecular diluents are explained on the basis of the difference in the nature of complexes extracted in these two distinctly different media as supported by the time resolved fluorescence (TRFS) study. An unusually high extractability and selectivity for Am(3+) over Eu(3+) with Me-BTP was attributed to the formation of a 1?:?4 complex for Am(3+), which was never reported earlier with any of the R-BTP derivatives in molecular diluents. DFT studies indicated higher metal 'd' and 'f' orbital participation (covalence) in the bonding with R-BTP in the case of Am(3+) complexes as compared to that in the case of Eu(3+) complexes, which resulted in the selectivity of these classes of ligands. The observed results may have a great significance in the radioactive waste management involving the partitioning and transmutation strategy. PMID:25736729

  12. Supported polymeric liquid membranes for wastewater treatment

    SciTech Connect

    Ho, S.V.

    1997-12-31

    The removal or elimination of organic residues from aqueous waste streams represents a major need in the chemical industry. A class of membrane has been developed called supported polymeric liquid membranes capable of removing and concentrating low molecular weight organic compounds from dilute aqueous solutions, especially those that also contain high concentrations of inorganic salts. These membranes are prepared by filling the pores of microfiltration or ultrafiltration membranes with polymeric (oligomeric) liquids having affinity for the organic compounds of interest. With this approach, membrane`s separation characteristics are decoupled from its mechanical stability and depend primarily on the chemical properties of the liquid polymer used. As a result, membranes of diverse separation capabilities can be conveniently prepared using liquid polymers possessing the appropriate functional groups. Physical properties typical of polymeric liquids such as high viscosity, extremely low volatility and insolubility in water contribute to the observed stability of the membranes under broad operating conditions. This membrane process has been successfully applied to several aqueous waste streams. This paper describes the early development activities for treating a waste stream containing a dilute mixture of C2-C6 carboxylic acids. Feasibility testings were initially carried out with flat sheet membranes in a small stirred cell. Scaleup was then conducted using hollow fiber membranes, first with small modules prepared in the laboratory, then with a much larger commercial module. Attractive features of this membrane process include the ability to recover the contaminants in concentrated form for either recycle or more economical disposal, low pressure (ambient) operation, simple scale-up using commercial hollow fiber modules, and ease of in-situ regeneration of the polymeric liquid.

  13. Radiolysis and Ageing of C2-BTP in Cinnamaldehyde/Hexanol Mixtures

    SciTech Connect

    Fermvik, Anna; Ekberg, Christian; Retegan, Teodora; Skarnemark, Gunnar

    2007-07-01

    The separation of actinides from lanthanides is an important step in the alternative methods for nuclear waste treatment currently under development. Polycyclic molecules containing nitrogen are synthesised and used for solvent extraction. A potential problem in the separation process is the degradation of the molecule due to irradiation or ageing. An addition of nitrobenzene has proved to have an inhibitory effect on degradation when added to a system containing C2-BTP in hexanol before irradiation. In this study, 2,6-di(5,6-diethyl-1,2,4-triazine-3-yl)pyridine (C2-BTP) was dissolved in different mixtures of cinnamaldehyde and hexanol and the effects on extraction after ageing and irradiation were investigated. Similar to nitrobenzene, cinnamaldehyde contains an aromatic ring which generally has a relatively high resistance towards radiolysis. Both C2-BTP in cinnamaldehyde and C2-BTP in hexanol seem to degrade with time. The system with C2-BTP in pure hexanol is relatively stable up to 17 days but then starts slowly to degrade. The solution with pure cinnamaldehyde as diluent started to degrade after only {approx}20 hours. The opposite is true for degradation caused by radiolysis; hexanol systems are more sensitive to radiolysis than cinnamaldehyde systems. Most of the radiolytic degradation took place during the first days of irradiation, up to a dose of 4 kGy. (authors)

  14. Development of Practical Supported Ionic Liquid Membranes: A Systematic Approach

    SciTech Connect

    Luebke, D.R.; Ilconich, J.B.; Myers, C.R.; Pennline, H.W.

    2007-11-01

    Supported liquid membranes (SLMs) are a class of materials that allow the researcher to utilize the wealth of knowledge available on liquid properties to optimize membrane performance. These membranes also have the advantage of liquid phase diffusivities, which are higher than those observed in polymers and grant proportionally greater permeabilities. The primary shortcoming of the supported liquid membranes demonstrated in past research has been the lack of stability caused by volatilization of the transport liquid. Ionic liquids, which may possess high CO2 solubility relative to light gases such as H2, are excellent candidates for this type of membrane since they are stable at elevated temperatures and have negligible vapor pressure. A study has been conducted evaluating the use of a variety of ionic liquids in supported ionic liquid membranes for the capture of CO2 from streams containing H2. In a joint project, researchers at the University of Notre Dame synthesized and characterized ionic liquids, and researchers at the National Energy Technology Laboratory incorporated candidate ionic liquids into supports and evaluated membrane performance for the resulting materials. Several steps have been taken in the development of practical supported ionic liquid membranes. Proof-of-concept was established by showing that ionic liquids could be used as the transport media in SLMs. Results showed that ionic liquids are suitable media for gas transport, but the preferred polymeric supports were not stable at temperatures above 135oC. The use of cross-linked nylon66 supports was found to produce membranes mechanically stable at temperatures exceeding 300oC but CO2/H2 selectivity was poor. An ionic liquid whose selectivity does not decrease with increasing temperature was needed, and a functionalized ionic liquid that complexes with CO2 was used. An increase in CO2/H2 selectivity with increasing temperature over the range of 37 to 85oC was observed and the dominance of a facilitated transport mechanism established. The presentation will detail membrane development, the effect of increasing transmembrane pressure, and preliminary results dealing with other gas pairs and contaminants.

  15. Carbon Dioxide Separation with Supported Ionic Liquid Membranes

    SciTech Connect

    Luebke, D.R.; Ilconich, J.B.; Myers, C.R.; Pennline, H.W.

    2007-04-01

    Supported liquid membranes are a class of materials that allow the researcher to utilize the wealth of knowledge available on liquid properties as a direct guide in the development of a capture technology. These membranes also have the advantage of liquid phase diffusivities higher than those observed in polymeric membranes which grant proportionally greater permeabilities. The primary shortcoming of the supported liquid membranes demonstrated in past research has been the lack of stability caused by volatilization of the transport liquid. Ionic liquids, which possess high carbon dioxide solubility relative to light gases such as hydrogen, are an excellent candidate for this type of membrane since they have negligible vapor pressure and are not susceptible to evaporation. A study has been conducted evaluating the use of several ionic liquids, including 1-hexyl-3-methyl-imidazolium bis(trifuoromethylsulfonyl)imide, 1-butyl-3-methyl-imidazolium nitrate, and 1-ethyl-3-methyl-imidazolium sulfate in supported ionic liquid membranes for the capture of carbon dioxide from streams containing hydrogen. In a joint project, researchers at the University of Notre Dame lent expertise in ionic liquid synthesis and characterization, and researchers at the National Energy Technology Laboratory incorporated candidate ionic liquids into supports and evaluated the resulting materials for membrane performance. Initial results have been very promising with carbon dioxide permeabilities as high as 950 barrers and significant improvements in carbon dioxide/hydrogen selectivity over conventional polymers at 37C and at elevated temperatures. Results include a comparison of the performance of several ionic liquids and a number of supports as well as a discussion of innovative fabrication techniques currently under development.

  16. 26. DETAIL OF CONCRETE PIPE SUPPORTS LEADING TO NEW LIQUID ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. DETAIL OF CONCRETE PIPE SUPPORTS LEADING TO NEW LIQUID HYDROGEN TANK FARM; VIEW TO WEST. - Cape Canaveral Air Station, Launch Complex 17, Facility 28402, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL

  17. Fabrication of fiber supported ionic liquids and methods of use

    DOEpatents

    Luebke, David R; Wickramanayake, Shan

    2013-02-26

    One or more embodiments relates to the production of a fabricated fiber having an asymmetric polymer network and having an immobilized liquid such as an ionic liquid within the pores of the polymer network. The process produces the fabricated fiber in a dry-wet spinning process using a homogenous dope solution, providing significant advantage over current fabrication methods for liquid-supporting polymers. The fabricated fibers may be effectively utilized for the separation of a chemical species from a mixture based on the selection of the polymer, the liquid, and the solvent utilized in the dope.

  18. Rejuvenation of Spent Media via Supported Emulsion Liquid Membranes

    NASA Technical Reports Server (NTRS)

    Wiencek, John M.

    2002-01-01

    The overall goal of this project was to maximize the reuseability of spent fermentation media. Supported emulsion liquid membrane separation, a highly efficient extraction technique, was used to remove inhibitory byproducts during fermentation; thus, improve the yield while reducing the need for fresh water. The key objectives of this study were: (1) Develop an emulsion liquid membrane system targeting low molecular weight organic acids which has minimal toxicity on a variety of microbial systems. (2) Conduct mass transfer studies to allow proper modeling and design of a supported emulsion liquid membrane system. (3) Investigate the effect of gravity on emulsion coalescence within the membrane unit. (4) Access the effect of water re-use on fermentation yields in a model microbial system. and (5) Develop a perfusion-type fermentor utilizing a supported emulsion liquid membrane system to control inhibitory fermentation byproducts (not completed due to lack of funds)

  19. Carbon Dioxide Separation with Supported Ionic Liquid Membranes

    SciTech Connect

    Luebke, D.R.; Ilconich, J.B.; Pennline, H.W.; Myers, C.R.

    2007-05-01

    A practical form of CO2 capture at water-gas shift conditions in the IGCC process could serve the dual function of producing a pure CO2 stream for sequestration and forcing the equilibrium-limited shift reaction to completion enriching the stream in H2. The shift temperatures, ranging from the low temperature shift condition of 260C to the gasification condition of 900C, limit capture options by diminishing associative interactions which favor removal of CO2 from the gas stream. Certain sorption interactions, such as carbonate formation, remain available but generally involve exceptionally high sorbent regeneration energies that contribute heavily to parasitic power losses. Carbon dioxide selective membranes need only establish an equilibrium between the gas phase and sorption states in order to transport CO2, giving them a potential energetic advantage over other technologies. Supported liquid membranes take advantage of high, liquid phase diffusivities and a solution diffusion mechanism similar to that observed in polymeric membranes to achieve superior permeabilities and selectivites. The primary shortcoming of the supported liquid membranes demonstrated in past research has been the lack of stability caused by volatilization of the transport liquid. Ionic liquids, which possess high CO2 solubility relative to light gases such as H2, are excellent candidates for this type of membrane since they have negligible vapor pressure and are not susceptible to evaporation. A study has been conducted evaluating the use of ionic liquids including 1-hexyl-3-methyl-imidazolium bis(trifuoromethylsulfonyl)imide in supported ionic liquid membranes for the capture of CO2 from streams containing H2. In a joint project, researchers at the University of Notre Dame synthesized and characterized ionic liquids, and researchers at the National Energy Technology Laboratory incorporated candidate ionic liquids into supports and evaluated the resulting materials for membrane performance. Improvements to the ionic liquid and support have allowed testing of these supported ionic liquid membranes at temperatures up to 300C without loss of support mechanical stability or degradation of the ionic liquid. Substantial improvements in selectivity have also been observed at elevated temperature with the best membrane currently achieving optimum performance at 75C.

  20. A BTP1 prophage gene present in invasive non-typhoidal Salmonella determines composition and length of the O-antigen of the lipopolysaccharide.

    PubMed

    Kintz, Erica; Davies, Mark R; Hammarlf, Disa L; Canals, Roco; Hinton, Jay C D; van der Woude, Marjan W

    2015-04-01

    Salmonella?Typhimurium isolate D23580 represents a recently identified ST313 lineage of invasive non-typhoidal Salmonellae (iNTS). One of the differences between this lineage and other non-iNTS S.?Typhimurium isolates is the presence of prophage BTP1. This prophage encodes a gtrC gene, implicated in O-antigen modification. GtrC(BTP) (1) is essential for maintaining O-antigen length in isolate D23580, since a gtr(BTP) (1) mutant yields a short O-antigen. This phenotype can be complemented by gtrC(BTP) (1) or very closely related gtrC genes. The short O-antigen of the gtr(BTP) (1) mutant was also compensated by deletion of the BTP1 phage tailspike gene in the D23580 chromosome. This tailspike protein has a putative endorhamnosidase domain and thus may mediate O-antigen cleavage. Expression of the gtrC(BTP) (1) gene is, in contrast to expression of many other gtr operons, not subject to phase variation and transcriptional analysis suggests that gtrC is produced under a variety of conditions. Additionally, GtrC(BTP) (1) expression is necessary and sufficient to provide protection against BTP1 phage infection of an otherwise susceptible strain. These data are consistent with a model in which GtrC(BTP) (1) mediates modification of the BTP1 phage O-antigen receptor in lysogenic D23580, and thereby prevents superinfection by itself and other phage that uses the same O-antigen co-receptor. PMID:25586744

  1. Alkaline ionic liquids applied in supported ionic liquid catalyst for selective hydrogenation of citral to citronellal

    PubMed Central

    Salminen, Eero; Virtanen, Pasi; Mikkola, Jyri-Pekka

    2014-01-01

    The challenge in preparation of ionic liquids containing a strong alkaline anion is to identify a suitable cation which can tolerate the harsh conditions induced by the anion. In this study, a commercial quaternary ammonium compound (quat) benzalkonium [ADBA] (alkyldimethylbenzylammonium) was used as a cation in the synthesis of different alkaline ionic liquids. In fact, the precursor, benzalkonium chloride, is a mixture of alkyldimethylbenzylammonium chlorides of various alkyl chain lengths and is commonly used in the formulation of various antiseptic products. The prepared ionic liquids were utilized as Supported Ionic Liquid Catalysts (SILCAs). Typically, a SILCA contains metal nanoparticles, enzymes, or metal complexes in an ionic liquid layer which is immobilized on a solid carrier material such as an active carbon cloth (ACC). The catalysts were applied in the selective hydrogenation of citral to citronellal which is an important perfumery chemical. Interestingly, 70% molar yield toward citronellal was achieved over a catalyst containing the alkaline ionic liquid benzalkonium methoxide. PMID:24790972

  2. Alkaline ionic liquids applied in supported ionic liquid catalyst for selective hydrogenation of citral to citronellal

    NASA Astrophysics Data System (ADS)

    Salminen, Eero; Virtanen, Pasi; Mikkola, Jyri-Pekka

    2014-02-01

    The challenge in preparation of ionic liquids containing a strong alkaline anion is to identify a suitable cation which can tolerate the harsh conditions induced by the anion. In this study, a commercial quaternary ammonium compound (quat) benzalkonium [ADBA] (alkyldimethylbenzylammonium) was used as a cation in the synthesis of different alkaline ionic liquids. In fact, the precursor, benzalkonium chloride, is a mixture of alkyldimethylbenzylammonium chlorides of various alkyl chain lengths and is commonly used in the formulation of various antiseptic products. The prepared ionic liquids were utilized as Supported Ionic Liquid Catalysts (SILCAs). Typically, a SILCA contains metal nanoparticles, enzymes or metal complexes in an ionic liquid layer which is immobilized on a solid carrier material such as an active carbon cloth (ACC). The catalysts were applied in the selective hydrogenation of citral to citronellal which is an important perfumery chemical. Interestingly, 70 % molar yield towards citronellal was achieved over a catalyst containing the alkaline ionic liquid benzalkonium methoxide.

  3. Extraction of molybdenum by a supported liquid membrane method.

    PubMed

    Basualto, Carlos; Marchese, Jos; Valenzuela, Fernando; Acosta, Adolfo

    2003-04-10

    This is a report on the extraction of molybdenum(VI) ions using a supported liquid membrane, prepared by dissolving in kerosene, the extractant Alamine 336 (a long-chain tertiary amine) employed as mobile carrier. A flat hydrophobic microporous membrane was utilised as solid support. Appropriate conditions for Mo(VI) extraction through the liquid membrane were obtained from the results of liquid-liquid extraction and stripping partition experiments. The influence of feed solution acidity, the carrier extractant concentration in the organic liquid film and the content of strip agent on the metal flux through membrane were investigated. It was established that maximal extraction of metal is achieved at a pH 2.0 if sulphuric acid is used in the feed solution and at a pH value over 11.0 if Na(2)CO(3) is used as strip agent. Moreover, the molybdenum extraction through membrane is enhanced when a 0.02 mol l(-1) content of the amine carrier in the organic phase is used. The present paper deals with an equilibrium investigation of the extraction of Mo(VI) by Alamine 336 and its permeation conditions through the liquid membrane, and examines a possible mechanism of extraction. PMID:18968990

  4. Rejuvenation of Spent Media via Supported Emulsion Liquid Membranes

    NASA Technical Reports Server (NTRS)

    Wiencek, John M.

    2002-01-01

    The overall goal of this project is to maximize the reuseability of spent fermentation media. Supported emulsion liquid membrane separation, a highly efficient extraction technique, is used to remove inhibitory byproducts during fermentation; thus, improving the yield while reducing the need for fresh water. The key objectives of this study are: Develop an emulsion liquid membrane system targeting low molecular weight organic acids which has minimal toxicity on a variety of microbial systems; Conduct mass transfer studies to allow proper modeling and design of a supported emulsion liquid membrane system; Investigate the effect of gravity on emulsion coalescence within the membrane unit; Access the effect of water re-use on fermentation yields in a model microbial system; Develop a perfusion-type fermentor utilizing a supported emulsion liquid membrane system to control inhibitory fermentation byproducts; Work for the coming year will focus on the determination of toxicity of various solvents, selection of the emulsifying agents, as well as characterizing the mass transfer of hollow-fiber contactors.

  5. Supported liquid inorganic membranes for nuclear waste separation

    DOEpatents

    Bhave, Ramesh R; DeBusk, Melanie M; DelCul, Guillermo D; Delmau, Laetitia H; Narula, Chaitanya K

    2015-04-07

    A system and method for the extraction of americium from radioactive waste solutions. The method includes the transfer of highly oxidized americium from an acidic aqueous feed solution through an immobilized liquid membrane to an organic receiving solvent, for example tributyl phosphate. The immobilized liquid membrane includes porous support and separating layers loaded with tributyl phosphate. The extracted solution is subsequently stripped of americium and recycled at the immobilized liquid membrane as neat tributyl phosphate for the continuous extraction of americium. The sequestered americium can be used as a nuclear fuel, a nuclear fuel component or a radiation source, and the remaining constituent elements in the aqueous feed solution can be stored in glassified waste forms substantially free of americium.

  6. Feasibility of Surfactant-Free Supported Emulsion Liquid Membrane Extraction

    NASA Technical Reports Server (NTRS)

    Hu, Shih-Yao B.; Li, Jin; Wiencek, John M.

    2001-01-01

    Supported emulsion liquid membrane (SELM) is an effective means to conduct liquid-liquid extraction. SELM extraction is particularly attractive for separation tasks in the microgravity environment where density difference between the solvent and the internal phase of the emulsion is inconsequential and a stable dispersion can be maintained without surfactant. In this research, dispersed two-phase flow in SELM extraction is modeled using the Lagrangian method. The results show that SELM extraction process in the microgravity environment can be simulated on earth by matching the density of the solvent and the stripping phase. Feasibility of surfactant-free SELM (SFSELM) extraction is assessed by studying the coalescence behavior of the internal phase in the absence of the surfactant. Although the contacting area between the solvent and the internal phase in SFSELM extraction is significantly less than the area provided by regular emulsion due to drop coalescence, it is comparable to the area provided by a typical hollow-fiber membrane. Thus, the stripping process is highly unlikely to become the rate-limiting step in SFSELM extraction. SFSELM remains an effective way to achieve simultaneous extraction and stripping and is able to eliminate the equilibrium limitation in the typical solvent extraction processes. The SFSELM design is similar to the supported liquid membrane design in some aspects.

  7. Liquid supported denture-management of flabby ridges.

    PubMed

    Mody, Pranav V; Kumar, Girish; Kumar, Manish; Shetty, Brijesh

    2012-07-01

    The ideal properties of a denture are adequate rigidity on polished surface to bear masticatory forces and at the same time, flexibility and softness on the tissue surface for proper and even distribution of masticatory forces. The problem with conventional denture is rigidity of tissue surface; leads to uneven distribution of load. This drawback even worsens in the case of flabby, atrophic and unemployed ridges with excessive bone resorption. The liquid supported denture allows continued adaptation and eliminates the disadvantages of denture designs based on the application of temporary tissue conditioners or soft liners. PMID:23293491

  8. [Preparation and applications of a supported liquid-liquid extraction column with a composite diatomite material].

    PubMed

    Bao, Jianmin; Ma, Zhishuang; Sun, Ying; Wang, Yongzun; Li, Youxin

    2012-08-01

    A rapid and special supported liquid-liquid extraction (SLE) column was developed with a composite diatomite material. The SLE column was evaluated by high performance liquid chromatography (HPLC) with acidic, neutral and alkaline compounds dissolved in water. Furthermore, some real complex samples were also analyzed by HPLC with the SLE method. The recoveries of benzoic acid (acidic), p-nitroaniline (alkaline) and 4-hydroxy-benzoic methyl ester (neutral) treated by the SLE column were 90.6%, 98.1% and 97.7%. However, the recoveries of the three compounds treated by traditional liquid-liquid extraction (LLE) method were 71.9%, 81.9% and 83.9%. The results showed that the SLE technique had higher recoveries than the traditional LLE method. The spiked recoveries of the complex samples, such as benzoic acid in Sprite and dexamethasone acetate, chlorphenamine maleate, indomethacin in bovine serum, were between 80% and 110% and the relative standard deviations (RSDs) were less than 15%. For biological specimen, the results could be accepted. Meantime, many disadvantages associated with traditional LLE method, such as emulsion formation, didn't occur using SLE column. The SLE column technique is a good sample preparation method with many advantages, such as rapid, simple, robust, easily automated, high recovery and high-throughput, which would be widely used in the future. PMID:23256382

  9. Systemic resistance and lipoxygenase-related defence response induced in tomato by Pseudomonas putida strain BTP1

    PubMed Central

    Akram, Adam; Ongena, Marc; Duby, Francline; Dommes, Jacques; Thonart, Philippe

    2008-01-01

    Background Previous studies showed the ability of Pseudomonas putida strain BTP1 to promote induced systemic resistance (ISR) in different host plants. Since ISR is long-lasting and not conducive for development of resistance of the targeted pathogen, this phenomenon can take part of disease control strategies. However, in spite of the numerous examples of ISR induced by PGPR in plants, only a few biochemical studies have associated the protective effect with specific host metabolic changes. Results In this study, we showed the protective effect of this bacterium in tomato against Botrytis cinerea. Following treatment by P. putida BTP1, analyses of acid-hydrolyzed leaf extracts showed an accumulation of antifungal material after pathogen infection. The fungitoxic compounds thus mainly accumulate as conjugates from which active aglycones may be liberated through the activity of hydrolytic enzymes. These results suggest that strain BTP1 can elicit systemic phytoalexin accumulation in tomato as one defence mechanism. On another hand, we have shown that key enzymes of the lipoxygenase pathway are stimulated in plants treated with the bacteria as compared with control plants. Interestingly, this stimulation is observed only after pathogen challenge in agreement with the priming concept almost invariably associated with the ISR phenomenon. Conclusion Through the demonstration of phytoalexin accumulation and LOX pathway stimulation in tomato, this work provides new insights into the diversity of defence mechanisms that are inducible by non-pathogenic bacteria in the context of ISR. PMID:19000301

  10. Dynamic hollow fiber-supported headspace liquid-phase microextraction.

    PubMed

    Jiang, Xianmin; Basheer, Chanbasha; Zhang, Jie; Lee, Hian Kee

    2005-09-16

    With the increasing concern over deteriorating environmental quality, the analysis of organic pollutants in air, water, and soil has become critically important. The development of simple, efficient, and inexpensive analytical sample pretreatment is crucial for monitoring and evaluating the environment. In this work, a dynamic hollow-fiber supported headspace liquid-phase microextraction (DHF-HS-LPME) approach was developed. In dynamic LPME, the extracting solvent is held within a hollow fiber, affixed to a syringe needle and immersed in the sample solution, and is moved to-and-fro by using a programmable syringe pump. The movement facilitates mass transfer from the sample to the solvent. Here, a similar approach was adopted, except that extraction was from the headspace rather than by direct immersion. Analysis of the extract was carried out by gas chromatography-mass spectrometry. The effect of sampling temperature, water, salt, dwelling time were investigated. Results indicated that this novel headspace microextraction method gave good analyte-enrichment factors, linear range, limits of detection and repeatability, all of which were evaluated by extracting PAHs from soil samples. This technique represents an inexpensive, convenient, fast and simple sample preparation of this class of semi-volatile organic compounds. PMID:16130726

  11. Electromembrane extraction through a virtually rotating supported liquid membrane.

    PubMed

    HosseinyDavarani, Saied Saeed; Moazami, Hamid Reza; Memarian, Elham; Nojavan, Saeed

    2016-01-01

    Electromembrane extraction (EME) of model analytes was carried out using a virtually rotating supported liquid membrane (SLM). The virtual (nonmechanical) rotating of the SLM was achieved using a novel electrode assembly including a central electrode immersed inside the lumen of the SLM and five counter electrodes surrounding the SLM. A particular electronic circuit was designed to distribute the potential among five counter electrodes in a rotating pattern. The effect of the experimental parameters on the recovery of the extraction was investigated for verapamil (VPL), trimipramine (TRP), and clomipramine (CLP) as the model analytes and 2-ethyl hexanol as the SLM solvent. The results showed that the recovery of the extraction is a function of the angular velocity of the virtual rotation. The best results were obtained at an angular velocity of 1.83 RadS(-1) (or a rotation frequency of 0.29 Hz).The optimization of the parameters gave higher recoveries up to 50% greater than those of a conventional EME method. The rotating also allowed the extraction to be carried out at shorter time (15 min) and lower voltage (200 V) with respect to the conventional extraction. The model analytes were successfully extracted from wastewater and human urine samples with recoveries ranging from 38 to 85%. The RSD of the determinations was in the range of 12.6 to 14.8%. PMID:26462723

  12. Advanced Supported Liquid Membranes for Carbon Dioxide Control in Extravehicular Activity Applications

    NASA Technical Reports Server (NTRS)

    Wickham, David T. (Inventor); Gleason, Kevin J. (Inventor); Cowley, Scott W. (Inventor)

    2015-01-01

    There is disclosed a portable life support system with a component for removal of at least one selected gas. In an embodiment, the system includes a supported liquid membrane having a first side and a second side in opposition to one another, the first side configured for disposition toward an astronaut and the second side configured for disposition toward a vacuum atmosphere. The system further includes an ionic liquid disposed between the first side and the second side of the supported liquid membrane, the ionic liquid configured for removal of at least one selected gas from a region housing the astronaut adjacent the first side of the supported liquid membrane to the vacuum atmosphere adjacent the second side of the supported liquid membrane. Other embodiments are also disclosed.

  13. The elicitation of a systemic resistance by Pseudomonas putida BTP1 in tomato involves the stimulation of two lipoxygenase isoforms

    PubMed Central

    2011-01-01

    Background Some non-pathogenic rhizobacteria called Plant Growth Promoting Rhizobacteria (PGPR) possess the capacity to induce in plant defense mechanisms effective against pathogens. Precedent studies showed the ability of Pseudomonas putida BTP1 to induce PGPR-mediated resistance, termed ISR (Induced Systemic Resistance), in different plant species. Despite extensive works, molecular defense mechanisms involved in ISR are less well understood that in the case of pathogen induced systemic acquired resistance. Results We analyzed the activities of phenylalanine ammonia-lyase (PAL) and lipoxygenase (LOX), key enzymes of the phenylpropanoid and oxylipin pathways respectively, in tomato treated or not with P. putida BTP1. The bacterial treatment did not stimulate PAL activity and linoleate-consuming LOX activities. Linolenate-consuming LOX activity, on the contrary, was significantly stimulated in P. putida BTP1-inoculated plants before and two days after infection by B. cinerea. This stimulation is due to the increase of transcription level of two isoforms of LOX: TomLoxD and TomLoxF, a newly identified LOX gene. We showed that recombinant TomLOXF preferentially consumes linolenic acid and produces 13-derivative of fatty acids. After challenging with B. cinerea, the increase of transcription of these two LOX genes and higher linolenic acid-consuming LOX activity were associated with a more rapid accumulation of free 13-hydroperoxy-octadecatrienoic and 13-hydroxy-octadecatrienoic acids, two antifungal oxylipins, in bacterized plants. Conclusion In addition to the discovery of a new LOX gene in tomato, this work is the first to show differential induction of LOX isozymes and a more rapid accumulation of 13-hydroperoxy-octadecatrienoic and 13-hydroxy-octadecatrienoic acids in rhizobacteria mediated-induced systemic resistance. PMID:21294872

  14. Liquid metal systems development: reactor vessel support structure evaluation

    SciTech Connect

    McEdwards, J.A.

    1981-01-01

    Results of an evaluation of support structures for the reactor vessel are reported. The U ring, box ring, integral ring, tee ring and tangential beam supports were investigated. The U ring is the recommended vessel support structure configuration.

  15. A BTP1 prophage gene present in invasive non-typhoidal Salmonella determines composition and length of the O-antigen of the lipopolysaccharide

    PubMed Central

    Kintz, Erica; Davies, Mark R; Hammarlöf, Disa L; Canals, Rocío; Hinton, Jay C D; van der Woude, Marjan W

    2015-01-01

    Salmonella Typhimurium isolate D23580 represents a recently identified ST313 lineage of invasive non-typhoidal Salmonellae (iNTS). One of the differences between this lineage and other non-iNTS S. Typhimurium isolates is the presence of prophage BTP1. This prophage encodes a gtrC gene, implicated in O-antigen modification. GtrCBTP1 is essential for maintaining O-antigen length in isolate D23580, since a gtrBTP1 mutant yields a short O-antigen. This phenotype can be complemented by gtrCBTP1 or very closely related gtrC genes. The short O-antigen of the gtrBTP1 mutant was also compensated by deletion of the BTP1 phage tailspike gene in the D23580 chromosome. This tailspike protein has a putative endorhamnosidase domain and thus may mediate O-antigen cleavage. Expression of the gtrCBTP1 gene is, in contrast to expression of many other gtr operons, not subject to phase variation and transcriptional analysis suggests that gtrC is produced under a variety of conditions. Additionally, GtrCBTP1 expression is necessary and sufficient to provide protection against BTP1 phage infection of an otherwise susceptible strain. These data are consistent with a model in which GtrCBTP1 mediates modification of the BTP1 phage O-antigen receptor in lysogenic D23580, and thereby prevents superinfection by itself and other phage that uses the same O-antigen co-receptor. PMID:25586744

  16. Performance evaluation of supported ionic liquid membrane for removal of phenol.

    PubMed

    Nosrati, S; Jayakumar, N S; Hashim, M A

    2011-09-15

    This work evaluates the performance of ionic liquid in supported liquid membrane (SLM) for the removal of phenol from wastewater. Ionic liquids are organic salts entirely composed of organic cations and either organic or inorganic anions. Due to the fact that the vapor pressure of ionic liquid is not detectable and they are sparingly soluble in most conventional solvents, they can be applied in SLM as the organic phase. In this work, 1-n-alkyl-3-methylimidazolium salts, [C(n)MIM](+)[X](-) have been investigated so as to determine an optimal supported ionic liquid membrane. The effect of operational parameters such as pH, stirring speed and the concentration of stripping agent has been studied, and an evaluation of different membrane supports were also carried out. With a minimal amount of the ionic liquid 1-Butyl-3-methylimidazolium hydrogensulfate, 85% phenol removal could be achieved by using polytetrafluoroethylene hydrophobic membrane filter in the SLM. PMID:21752542

  17. Hyperhydricity and flavonoid content of Scutellaria species in vitro on polyester-supported liquid culture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three Scutellaria species (Scutellaria lateriflora, S. costaricana and S. baicalensis) were grown in different in vitro physical environments: agar, liquid culture, and liquid culture with fiber-supported paper (with initial media volumes of 20 mL and 30 mL). During an eight-week time course, tiss...

  18. Nanopore stochastic detection of a liquid explosive component and sensitizers using boromycin and an ionic liquid supporting electrolyte.

    PubMed

    Jayawardhana, Dilani A; Crank, Jeffrey A; Zhao, Qitao; Armstrong, Daniel W; Guan, Xiyun

    2009-01-01

    We report a rapid and sensitive stochastic nanopore sensing method for the detection of monovalent cations and liquid explosive components and their sensitizers. The sensing element is a wild-type alpha-hemolysin protein pore with boromycin as a molecular adaptor, while a solution containing an ionic liquid was used as the background electrolyte. The analyte-boromycin complexes showed significantly different signatures. Specifically, their event mean dwell times and amplitudes were sufficiently distinct to permit the convenient differentiation and even simultaneous detection of liquid explosive components in aqueous environments. In addition, the results also demonstrate that the usage of specific ionic liquid salt solutions instead of NaCl or KCl solution as supporting electrolyte provides a useful means to greatly enhance the sensitivity of the nanopore for some analytes in stochastic sensing. PMID:19055422

  19. Early transcriptional responses of bovine chorioallantoic membrane explants to wild type, ΔvirB2 or ΔbtpB Brucella abortus infection.

    PubMed

    Mol, Juliana P S; Costa, Erica A; Carvalho, Alex F; Sun, Yao-Hui; Tsolis, Reneé M; Paixão, Tatiane A; Santos, Renato L

    2014-01-01

    The pathogenesis of the Brucella-induced inflammatory response in the bovine placenta is not completely understood. In this study we evaluated the role of the B. abortus Type IV secretion system and the anti-inflammatory factor BtpB in early interactions with bovine placental tissues. Transcription profiles of chorioallantoic membrane (CAM) explants inoculated with wild type (strain 2308), ΔvirB2 or ΔbtpB Brucella abortus were compared by microarray analysis at 4 hours post infection. Transcripts with significant variation (>2 fold change; P<0.05) were functionally classified, and transcripts related to defense and inflammation were assessed by quantitative real time RT-PCR. Infection with wild type B. abortus resulted in slightly more genes with decreased than increased transcription levels. Conversely, infection of trophoblastic cells with the ΔvirB2 or the ΔbtpB mutant strains, that lack a functional T4SS or that has impaired inhibition of TLR signaling, respectively, induced more upregulated than downregulated genes. Wild type Brucella abortus impaired transcription of host genes related to immune response when compared to ΔvirB and ΔbtpB mutants. Our findings suggest that proinflammatory genes are negatively modulated in bovine trophoblastic cells at early stages of infection. The virB operon and btpB are directly or indirectly related to modulation of these host genes. These results shed light on the early interactions between B. abortus and placental tissue that ultimately culminate in inflammatory pathology and abortion. PMID:25259715

  20. Early Transcriptional Responses of Bovine Chorioallantoic Membrane Explants to Wild Type, ΔvirB2 or ΔbtpB Brucella abortus Infection

    PubMed Central

    Mol, Juliana P. S.; Costa, Erica A.; Carvalho, Alex F.; Sun, Yao-Hui; Tsolis, Reneé M.; Paixão, Tatiane A.; Santos, Renato L.

    2014-01-01

    The pathogenesis of the Brucella-induced inflammatory response in the bovine placenta is not completely understood. In this study we evaluated the role of the B. abortus Type IV secretion system and the anti-inflammatory factor BtpB in early interactions with bovine placental tissues. Transcription profiles of chorioallantoic membrane (CAM) explants inoculated with wild type (strain 2308), ΔvirB2 or ΔbtpB Brucella abortus were compared by microarray analysis at 4 hours post infection. Transcripts with significant variation (>2 fold change; P<0.05) were functionally classified, and transcripts related to defense and inflammation were assessed by quantitative real time RT-PCR. Infection with wild type B. abortus resulted in slightly more genes with decreased than increased transcription levels. Conversely, infection of trophoblastic cells with the ΔvirB2 or the ΔbtpB mutant strains, that lack a functional T4SS or that has impaired inhibition of TLR signaling, respectively, induced more upregulated than downregulated genes. Wild type Brucella abortus impaired transcription of host genes related to immune response when compared to ΔvirB and ΔbtpB mutants. Our findings suggest that proinflammatory genes are negatively modulated in bovine trophoblastic cells at early stages of infection. The virB operon and btpB are directly or indirectly related to modulation of these host genes. These results shed light on the early interactions between B. abortus and placental tissue that ultimately culminate in inflammatory pathology and abortion. PMID:25259715

  1. A Monolithic Hybrid Cellulose-2.5-Acetate/Polymer Bioreactor for Biocatalysis under Continuous Liquid-Liquid Conditions Using a Supported Ionic Liquid Phase.

    PubMed

    Sandig, Bernhard; Michalek, Lukas; Vlahovic, Sandra; Antonovici, Mihaela; Hauer, Bernhard; Buchmeiser, Michael R

    2015-10-26

    Mesoporous monolithic hybrid cellulose-2.5-acetate (CA)/polymer supports were prepared under solvent-induced phase separation conditions using cellulose-2.5-acetate microbeads 8-14??m in diameter, 1,1,1-tris(hydroxymethyl)propane and 4,4'-methylenebis(phenylisocyanate) as monomers as well as THF and n-heptane as porogenic solvents. 4-(Dimethylamino)pyridine and dibutyltin dilaurate (DBTDL), respectively, were used as catalysts. Monolithic hybrid supports were used in transesterification reactions of vinyl butyrate with 1-butanol under continuous, supported ionic liquid-liquid conditions with Candida antarctica lipase?B (CALB) and octylmethylimidazolium tetrafluoroborate ([OMIM(+) ][BF4 (-) ]) immobilized within the CA beads inside the polymeric monolithic framework and methyl tert-butyl ether (MTBE) as the continuous phase. The new hybrid bioreactors were successfully used in dimensions up to 230?cm (V=94?mL). Under continuous biphasic liquid-liquid conditions a constant conversion up to 96?% was achieved over a period of 18?days, resulting in a productivity of 58??mol?mg(-1) (CALB)?min(-1) . This translates into an unprecedented turnover number (TON) of 3.910(7) within two weeks, which is much higher than the one obtained under standard biphasic conditions using [OMIM(+) ][BF4 (-) ]/MTBE (TON=2.710(6) ). The continuous liquid-liquid setup based on a hybrid reactor presented here is strongly believed to be applicable to many other enzyme-catalyzed reactions. PMID:26493884

  2. SEPARATION PROPERTIES OF SURFACE MODIFIED SILICA SUPPORTED LIQUID MEMBRANES FOR DIVALENT METAL REMOVAL/RECOVERY

    EPA Science Inventory

    The synthesis and separation properties of a mesoporous silica supported liquid membrane (SLM) were studied. The membranes consisted of a silica layer, from dip-coated colloidal silica, on a a-alumina support, modified with DCDMS (dichlorodimethyl silane) to add surface methyl g...

  3. Biopolymer-supported ionic-liquid-phase ruthenium catalysts for olefin metathesis.

    PubMed

    Clousier, Nathalie; Filippi, Alexandra; Borr, Etienne; Guibal, Eric; Crvisy, Christophe; Caijo, Frderic; Mauduit, Marc; Dez, Isabelle; Gaumont, Annie-Claude

    2014-04-01

    Original ruthenium supported ionic liquid phase (SILP) catalysts based on alginates as supports were developed for olefin metathesis reactions. The marine biopolymer, which fulfills most of the requisite properties for a support such as widespread abundance, insolubility in the majority of organic solvents, a high affinity for ionic liquids, high chemical stability, biodegradability, low cost, and easy processing, was impregnated by [bmim][PF6 ] containing an ionically tagged ruthenium catalyst. These biosourced catalysts show promising performances in ring-closing metathesis (RCM) and cross-metathesis (CM) reactions, with a high level of recyclability and reusability combined with a good reactivity. PMID:24616203

  4. Modeling of the mass transfer rates of metal ions across supported liquid membranes. 1: Theory

    SciTech Connect

    Elhassadi, A.A.; Do, D.D.

    1999-01-01

    This paper deals with the modeling of the transport and separation of metal ions across supported liquid membranes. The mass transfer resistance at the liquid-membrane interfaces and the interfacial chemical reactions at both the extracting side and the stripping side are taken into account in the model equations. Simple analysis of the time scale of the system shows the influence of various important parameters and their interactions on the overall transport rate. Parametric studies are also dealt with in this paper.

  5. Extraction of aluminum from a pickling bath with supported liquid membrane extraction

    SciTech Connect

    Berends, A.M.; Witkamp, G.J.; Rosmalen, G.M. van

    1999-04-01

    Large amounts of waste are produced yearly in the galvanic and chemical surface treatment industry. Bath liquids used in the various processes lose their function due to contamination. The spent bath liquids have to be replaced and treated prior to disposal, leading to high costs and a high environmental burden. In this paper, a proposed solution to the problem is investigated: the selective removal of the contaminant with supported liquid membrane extraction. The extraction of aluminum, a contaminant at high concentrations, from a pickling bath liquid with hydrofluoric acid and phosphoric acid as its main components has been carried out with the basic extractants Alamine 308 and Alamine 336 in a flat sheet-supported liquid membrane setup. Aluminum transport rates were obtained in the order of 10{sup {minus}6}--10{sup {minus}5} mol/(m{sup 2} {center_dot} s), which are normal values for this technique. The extraction was not completely selective as dissolved phosphorus was coextracted. In all experiments, precipitation took place on the surface of the liquid membrane and in the bulk of the strip phase. Increasing the stripping alkalinity from pH = 8 to pH = 13 reduced the amount of precipitation in the bulk of the strip phase but caused a substantial decrease in the aluminum flux. The precipitation prevents industrial application of the systems investigated.

  6. The Effect of Microporous Polymeric Support Modification on Surface and Gas Transport Properties of Supported Ionic Liquid Membranes.

    PubMed

    Akhmetshina, Alsu A; Davletbaeva, Ilsiya M; Grebenschikova, Ekaterina S; Sazanova, Tatyana S; Petukhov, Anton N; Atlaskin, Artem A; Razov, Evgeny N; Zaripov, Ilnaz I; Martins, Carla F; Neves, Lusa A; Vorotyntsev, Ilya V

    2015-01-01

    Microporous polymers based on anionic macroinitiator and toluene 2,4-diisocyanate were used as a support for 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF?]) and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([emim][Tf?N]) immobilization. The polymeric support was modified by using silica particles associated in oligomeric media, and the influence of the modifier used on the polymeric structure was studied. The supported ionic liquid membranes (SILMs) were tested for He, N?, NH?, H?S, and CO? gas separation and ideal selectivities were calculated. The high values of ideal selectivity for ammonia-based systems with permanent gases were observed on polymer matrixes immobilized with [bmim][PF?] and [emim][Tf?N]. The modification of SILMs by nanosize silica particles leads to an increase of NH? separation relatively to CO? or H?S. PMID:26729177

  7. High Temperature Separation of Carbon Dioxide/Hydrogen Mixtures Using Facilitated Supported Ionic Liquid Membranes

    SciTech Connect

    Myers, C.R.; Pennline, H.W.; Luebke, D.R.; Ilconich, J.B.; Dixon, J.K.; Maginn, E.J.; Brennecke, J.F.

    2008-09-01

    Efficiently separating CO2 from H2 is one of the key steps in the environmentally responsible uses of fossil fuel for energy production. A wide variety of resources, including petroleum coke, coal, and even biomass, can be gasified to produce syngas (a mixture of COand H2). This gas stream can be further reacted with water to produce CO2 and more H2. Once separated, the CO2 can be stored in a variety of geological formations or sequestered by other means. The H2 can be combusted to operate a turbine, producing electricity, or used to power hydrogen fuel cells. In both cases, onlywater is produced as waste. An amine functionalized ionic liquid encapsulated in a supported ionic liquid membrane (SILM) can separate CO2 from H2 with a higher permeability and selectivity than any known membrane system. This separation is accomplished at elevated temperatures using facilitated transport supported ionic liquid membranes.

  8. Liquid phase methanol LaPorte process development unit: Modification, operation, and support studies

    SciTech Connect

    Not Available

    1991-02-02

    This report consists of Detailed Data Acquisition Sheets for Runs E-6 and E-7 for Task 2.2 of the Modification, Operation, and Support Studies of the Liquid Phase Methanol Laporte Process Development Unit. (Task 2.2: Alternate Catalyst Run E-6 and Catalyst Activity Maintenance Run E-7).

  9. Ionic liquid supported organotin reagents to prepare molecular imaging and therapy agents.

    PubMed

    Rajerison, Holisoa; Faye, Djibril; Roumesy, Aurlia; Louaisil, Nicolas; Boeda, Fabien; Faivre-Chauvet, Alain; Gestin, Jean-Franois; Legoupy, Stphanie

    2016-02-01

    Efficiency of ionic liquid supported organotin reagents in halodemetalation reaction has been investigated. High radiochemical yields of astatinated and iodinated compounds have been obtained using simple work-up procedure. This methodology represents a straightforward approach for the preparation of molecular imaging and therapy agents in nuclear medicine. PMID:26782686

  10. Evaluation of LMR (liquid metal reactors) core support concepts under seismic events

    SciTech Connect

    Wu, Ting-shu; Seidensticker, R.W.

    1989-01-01

    In the design of the core support system for liquid metal reactors (LMR) against earthquakes, the major concerns are directed toward the structural integrity as well as the reactivity control. This means that, in addition to the stress levels, maximum displacements and accelerations should also be within their allowable limits. This investigation studies the seismic responses of a large pool-type LMR with different design approaches to support the reactor core. Different core support designs yield different frequency ranges and responses. Responses of these designs to the given floor response spectra are required to satisfy a set of criteria which are common to all designs. 5 refs., 4 figs.

  11. Mechanism of Ion Transfer in Supported Liquid Membrane Systems: Electrochemical Control over Membrane Distribution

    PubMed Central

    2013-01-01

    A polarization study carried out on a thin supported liquid membrane separating two aqueous compartments is presented. Transfer of both the ionized and uncharged form of an organic tracer dye, rhodamine B ([9-(2-carboxyphenyl)-6-diethylamino-3-xanthenylidene]-diethylammonium chloride), across supported liquid membranes composed of one of 1-octanol (octan-1-ol), 1,9-decadiene (deca-1,9-diene), 1,2-dichlorobenzene, or nitrophenyl octyl ether (1-(2-nitrophenoxy)octane) was studied using cyclic voltammetry and UVvis absorption spectrophotometry. Concentration analysis indicates that the high membrane concentration of rhodamine B determines the ionic transfer observed via voltammetry, which is consistent with the low aqueous ionic concentration and large membrane/aqueous distribution of the molecule. The observed double-transfer voltammogram, although it has been largely neglected in previous literature, is a logical consequence of the presence of two liquidliquid interfaces and is rationalized in terms of ion transfer across the two interfaces on either side of the membrane and supported by voltammograms obtained for a series of ions of varied lipophilicity. The bipolar nature of the voltammetric response offers an effective way of mass transport control via changing polarity of the applied voltage and finds immediate use in extraction, purification, and separation applications. PMID:24299270

  12. Carbon Dioxide Selective Supported Ionic Liquid Membranes: The Effect of Contaminants

    SciTech Connect

    Luebke, D.R.; Ilconich, J.B.; Myers, C.R.; Pennline, H.W.

    2008-04-01

    The integrated gasification combined cycle (IGCC) is widely viewed as a promising technology for the large scale production of energy in a carbon constrained world. These cycles, which include gasification, contaminant removal, water-gas shift, CO2 capture and compression, and combustion of the reduced-carbon fuel gas in a turbine, often have significant efficiency advantages over conventional combustion technologies. A CO2 selective membrane capable of maintaining performance at conditions approaching those of low temperature water-gas shift (260oC) could facilitate the production of carbon-neutral energy by simultaneously driving the shift reaction to completion and concentrating CO2 for sequestration. Supported ionic liquid membranes (SILMs) have been previously evaluated for this application and determined to be physically and chemically stable to temperatures in excess of 300oC. These membranes were based on ionic liquids which interacted physically with CO2 and diminished considerably in selectivity at higher temperatures. To alleviate this problem, the original ionic liquids were replaced with ionic liquids able to form chemical complexes with CO2. These complexing ionic liquid membranes have a local maximum in selectivity which is observed at increasing temperatures for more stable complexes. Efforts are currently underway to develop ionic liquids with selectivity maxima at temperatures greater than 75oC, the best result to date, but other practical concerns must also be addressed if the membrane is to be realistically expected to function under water-gas shift conditions. A CO2 selective membrane must function not only at high temperature, but also in the presence of all the reactants and contaminants likely to be present in coal-derived fuel gas, including water, CO, and H2S. A study has been undertaken which examines the effects of each of these gases on both complexing and physically interacting supported liquid membranes. In a joint project, researchers at the University of Notre Dame synthesized and characterized ionic liquids, and researchers at the National Energy Technology Laboratory incorporated candidate ionic liquids into supports and evaluated the resulting materials for membrane performance.

  13. Determination of phthalate ester plasticizers in the aquatic environment using hollow fibre supported liquid membranes

    NASA Astrophysics Data System (ADS)

    Mtibe, A.; Msagati, Titus A. M.; Mishra, Ajay K.; Mamba, Bhekie B.

    Phthalates are known to be carcinogenic, teratogenic as well as endocrine disruptors. The potential risk to human and animals health generated from them has drawn great attention all over the world. Hollow fibre supported liquid membrane (HFSLM) online with high pressure liquid chromatography (HPLC) was used to determine benzyl butyl phthalate (BBP), dibutyl phthalate (DBP) and Diethylhexyl phthalate (DEHP) in wastewater. Toluene, di-n-hexyl ether and undecane were used as liquid barriers separating both donor (sample) and acceptor phase. Toluene performed much better than undecane and was used in sample preparation. The presence of toluene showed the potential for the enrichment and removal of phthalates to the concentrations ranges from 0 to 1.7 mg L-1.

  14. Ignition Capsules with Aerogel-Supported Liquid DT Fuel For The National Ignition Facility

    SciTech Connect

    Ho, D D; Salmonson, J D; Clark, D S; Lindl, J D; Haan, S W; Amendt, P; Wu, K J

    2011-10-25

    For high repetition-rate fusion power plant applications, capsules with aerogel-supported liquid DT fuel can have much reduced fill time compared to {beta}-layering a solid DT fuel layer. The melting point of liquid DT can be lowered once liquid DT is embedded in an aerogel matrix, and the DT vapor density is consequently closer to the desired density for optimal capsule design requirement. We present design for NIF-scale aerogel-filled capsules based on 1-D and 2-D simulations. An optimal configuration is obtained when the outer radius is increased until the clean fuel fraction is within 65-75% at peak velocity. A scan (in ablator and fuel thickness parameter space) is used to optimize the capsule configurations. The optimized aerogel-filled capsule has good low-mode robustness and acceptable high-mode mix.

  15. Development of a Supported Emulsion Liquid Membrane System for Propionic Acid Separation in a Microgravity Environment

    NASA Technical Reports Server (NTRS)

    Li, Jin; Hu, Shih-Yao B.; Wiencek, John M.

    2001-01-01

    Perstractive fermentation is a good way to increase the productivity of bioreactors. Using Propionibacteria as the model system, the feasibility of using supported emulsion liquid membrane (SELM) for perstractive fermentation is assessed in this study. Five industrial solvents were considered as the solvent for preparing the SELM. The more polar a solvent is, the higher the partition coefficient. However, toxicity of a solvent also increases with its polarity. CO-1055 (industrial decanol/octanol blend) has the highest partition coefficient toward propionic acid among the solvents that has no molecular toxicity toward Propionibacteria. A preliminary extraction study was conducted using tetradecane as solvent in a hydrophobic hollow fiber contactor. The result confirmed that SELM eliminates the equilibrium limitation of conventional liquid-liquid extraction, and allows the use of a non-toxic solvent with low partition coefficient.

  16. Ultra-hydrophobic ionic liquid 1-hexyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate supported hollow-fiber membrane liquid-liquid-liquid microextraction of chlorophenols.

    PubMed

    Ge, Dandan; Lee, Hian Kee

    2015-01-01

    An ultra-hydrophobic ionic liquid, 1-hexyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate ([HMIM][FAP]) was immobilized in the pores of a polypropylene hollow fiber for liquid-liquid-liquid microextraction (HF-LLLME) of chlorophenols (CPs) (4-chloro-3-methylphenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol). The analytes were first extracted from 10 ml of water sample into the ionic liquid membrane, and then were extracted back into 5 μl of sodium hydroxide aqueous solution in the hollow fiber channel. After extraction, the acceptor solution was directly injected into a high-performance liquid chromatographic system for analysis. Extraction parameters such as extraction time, salt concentration in the sample, the pH of the sample and acceptor phase, and stirring rate during extraction were investigated. The relative standard deviations of the analytes varied from 4 to 6%. Limits of detection of <0.5 ng/ml were obtained for the three analytes. The squared regression coefficients relating to the calibration curve were ≥0.9941. The proposed method was applied to the analysis of CPs in canal water. PMID:25476289

  17. Extraction of palladium(II) using Cyanex 471 extractant and supported liquid membrane

    SciTech Connect

    Walker, R.D.

    1984-12-01

    Cyanex 471 has potential in separating Pd(II) from chloride solutions containing Pt(IV). Liquid-liquid extraction equilibria studies have demonstrated that Cyanex 471 could be used to recover palladium(II) from spent automotive catalysts. The distribution equilibria and solution chemistry of the PdCl/sub 2/-HCl-H/sub 2/O-Cyanex 471-xylene system is straightforward until PtCl/sub 4/ is added to the system, upon which the system becomes extremely complex with various complexing reactions competing at the interface. Cyanex 471 has a major problem in applications using supported liquid membranes. The extracted palladium complex becomes saturated and precipitates as a dark brown solid before diffusion of the complex across the membrane can occur. Since the loading capacity of Cyanex 471 is very high, this is not a problem in solvent extraction. In supported liquid membrane extraction, the capacity of the membrane to retain Cyanex 471 in its tortuous pores is limited, causing precipi

  18. Supported Room Temperature Ionic Liquid Membranes for CO{sub 2}/CH{sub 4} Separation

    SciTech Connect

    Iarikov, D. D.; Hacarlioglu, P.; Oyama, S. T.

    2011-01-01

    Room temperature ionic liquids (RTILs) are organic salts which are liquid at or around room temperature. These compounds exhibit many outstanding physical properties such as great thermal stability and no measurable vapor pressure. In this work supported ionic liquid membranes (SILMs) were prepared by impregnating pores of α-alumina inorganic supports with various ionic liquids. In addition to membranes prepared with pure RTILs we were able to synthesize membranes with RTIL mixtures using 1-aminopyridinium iodide dissolved in 1-butyl-4-methylpyridinium tetrafluoroborate or methyltrioctylammonium bis(trifluoromethylsulfonyl)imide. This combination of an RTIL with an organic salt containing an amine group dramatically improved the membrane separation properties. The SILMs displayed CO{sub 2} permeance on the order of 5 × 10{sup −10} to 5 × 10{sup −9} mol m{sup −2} s{sup −1} Pa{sup −1} combined with CO{sub 2}/CH{sub 4} selectivity of 5–30. Although these values are comparable with the current systems for CO{sub 2} purification, CO{sub 2} permeance is still rather low for these compounds.

  19. A paper-supported graphene-ionic liquid array for e-nose application.

    PubMed

    Zhu, X; Liu, D; Chen, Q; Lin, L; Jiang, S; Zhou, H; Zhao, J; Wu, J

    2016-02-01

    A flexible graphene sensor array has been fabricated by in situ reduction of a graphene oxide (GO) array patterned on a paper chip. To achieve cross-reactive sensing and gas discrimination ability, the surface of each reduced GO (rGO) spot was modified with different types of ionic liquids (ILs), which could significantly alter the semiconductor properties and consequently the gas sensing behaviour of the paper-supported rGO sensor. PMID:26794831

  20. Constructing CO2-facilitated transport highway in supported ionic liquid membranes

    NASA Astrophysics Data System (ADS)

    Sun, Xiang Jun; Luo, Ju Jie; Zhang, Meng; Li, Jin Ping

    2014-01-01

    A Carbon dioxide-facilitated transport highway (CO2-FTH) on the microporous surface of a membrane matrix was designed using the amino carrier 3-aminopropyltriethoxysilane (APTES). Owing to the reversible reaction between CO2 molecules and fixed-site carriers, this supported ionic liquid membrane was able to selectively transfer CO2 more quickly. This concept may inspire means of fabricating a highly permeable and selective membrane to break through Robeson's upper bound.

  1. Study of cyanide wastewater treatment by dispersion supported liquid membrane using trioctylamine and kerosene as liquid membrane.

    PubMed

    Li, Guo Ping; Xue, Juan Qin; Yu, Li Hua; Liu, Ni Na

    2015-01-01

    A certain amount of cyanide is present in wastewater of various industrial processes, such as wet extraction of gold, coal processing, electroplating and other industries. In this work, an experimental study regarding transport of cyanide through a dispersion supported liquid membrane was performed. A model was established to describe the reaction and transport of CN(I) in the supported liquid membrane and the mass transfer kinetics equations were deduced. Through mass transfer kinetic equation it was derived that, when the carrier concentration was under certain conditions, there was a linear relationship between the reciprocal of the permeability coefficient of CN(I) (1/Pc) and n-th power of the concentration of H+ (cnH+), and the parameters ?a(?a/da) and ?o(?0/d0) could be obtained from the slope and intercept of the straight line. Then the diffusion coefficient do and the diffusion layer thickness ?o of the phase interface between the feed phase and membrane phase could be calculated. Factors affecting migration of CN(I) were analyzed, and the stable removal rate of CN(I) was more than 90% with carrier concentration (%TOA) of 2%, feed phase pH of 4, initial CN(I) concentration of 30 mg/L, stirring time of 1 hour, volume ratio of membrane solution to NaOH solution of 2:1, strip phase concentration of 2 mol/L. The results showed that the overall mass transfer rate increased first and then decreased with an increase of TOA concentration, organic-to-strip volume ratio, and strip concentration. Furthermore, the transport percentage of CN(I) was increased, the stability of membrane was enhanced, and the lifetime of the membrane was extended. PMID:26247764

  2. Chiroptical Probing of Lanthanide-Directed Self-Assembly Formation Using btp Ligands Formed in One-Pot Diazo-Transfer/Deprotection Click Reaction from Chiral Amines.

    PubMed

    Byrne, Joseph P; Martnez-Calvo, Miguel; Peacock, Robert D; Gunnlaugsson, Thorfinnur

    2016-01-11

    A series of enantiomeric 2,6-bis(1,2,3-triazol-4-yl)pyridines (btp)-containing ligands was synthesized by a one-pot two-step copper-catalyzed amine/alkyne click reaction. The Eu(III) - and Tb(III) -directed self-assembly formation of these ligands was studied in CH3 CN by monitoring their various photophysical properties, including their emerging circular dichroism and circularly polarized luminescence. The global analysis of the former enabled the determination of both the stoichiometry and the stability constants of the various chiral supramolecular species in solution. PMID:26555573

  3. An interpretation of the multiple fluid-fluid transitions in liquid supported amphiphile monolayers

    NASA Astrophysics Data System (ADS)

    Shin, Seokmin; Wang, Zhen-Ghang; Rice, Stuart A.

    1990-01-01

    We describe an extension of the generalized regular solution model of a liquid supported monolayer of long chain amphiphile molecules in which chain-chain interactions outside the surface layer are included as well as the effects of chain flexibility in the surface and in the space above the surface layer. Self-consistent equations for the distribution of molecular configurations and the surface density and pressure are derived by using a model free energy expression. Two first order fluid-fluid phase transitions are predicted for three different models for the chain-chain interactions outside the surface. These transitions are identified as the observed gas-to-``liquid-expanded'' and liquid-expanded-to-``liquid-condensed'' phase transitions in a monolayer, the first to be associated with the condensation of the in-surface portions of the amphiphile chains and the second to be associated with the condensation of the out of surface portions of the amphiphile chains. This interpretation comes from the observation of the different distributions of the molecular configurations in the coexistence regions for the two transitions and is reinforced by the analysis of the sensitivity of the equation of state to the parameters used in the model. The theory leads to a simple and qualitative but accurate physical picture of the successive fluid-fluid transitions of the monolayer.

  4. XPS analysis of activated carbon supported ionic liquids: Enhanced purity and reduced charging

    NASA Astrophysics Data System (ADS)

    Foelske-Schmitz, A.; Weingarth, D.; Ktz, R.

    2011-12-01

    Herein we report on XPS measurements on five different [EMIM] based ionic liquids (IL) prepared on activated carbon and aluminium supports. The anions were [TFSI], [BF4], [FAP], [B(CN)4] and [EtOSO3]. The results show that impurities such as O, Si or hydrocarbons were significantly reduced or no longer detected when preparation was performed on the high surface area carbon support. All core level spectra were fitted and for [EMIM][FAP], [EMIM][B(CN)4] and [EMIM][EtOSO3] de-convolution procedures of the C 1s lines are suggested. Comparison of the determined binding energies with published data strongly suggests that sample charging is irrelevant when preparation is performed on the activated carbon support. This observation is supposed to refer to the high capacitance of the high surface area carbon.

  5. A supported polymeric liquid membrane process for removal of carboxylic acids from a waste stream

    SciTech Connect

    Ho, S.V.

    1999-12-31

    The removal or elimination of organic residues from aqueous waste streams represents a major need in the chemical industry. The authors have developed a new class of membrane called supported polymeric liquid membranes that are capable of removing and concentrating low molecular weight organic compounds from dilute aqueous solutions, especially those that also contain high concentrations of inorganic salts. Attractive features of this membrane process include the ability to recover the contaminants in concentrated form for either recycle or more economical disposal, low pressure (ambient) operation, simple scale-up using commercial hollow fiber modules, and ease of in-situ regeneration of the polymeric liquid. The process has shown treatment feasibility for several types of aqueous waste streams. This paper describes the laboratory development activities for treating a waste stream containing a dilute mixture of C2-C6 carboxylic acids and nitric acid.

  6. The simultaneous stripping of arsenic and selenium from wastewaters using hollow-fibre supported liquid membranes.

    PubMed

    Mafu, Lihle D; Msagati, Titus A M; Mamba, Bhekie B

    2014-12-01

    The extraction of total arsenic and selenium using hollow-fibre supported liquid membranes (HFSLMs), with specific interest in the optimal conditions for the extraction in wastewater, is reported. The extraction time, type of liquid membrane, sample and donor pH and stirring rate were optimised, and thereafter, the developed method was tested in real wastewater samples. The optimal HFSLMs adopted, after optimisation tests, comprised of Aliquat 336, 0.8M NaOH, 200rpm and 80min as the extractant, stripping phase, stirring rate and reaction time, respectively. The developed method had reasonable-to-high extraction efficiencies in real wastewater samples with the final effluent recording as high as 73 and 78% removal efficiencies for Se and As, respectively. Considering the initial concentrations found in the samples, use of this developed method could bring down the concentrations to levels admissible by the United States Environmental Protection Agency (US-EPA) and World Health Organisation (WHO). PMID:25252794

  7. Supported liquid membrane-liquid chromatography-mass spectrometry analysis of cyanobacterial toxins in fresh water systems

    NASA Astrophysics Data System (ADS)

    Mbukwa, Elbert A.; Msagati, Titus A. M.; Mamba, Bhekie B.

    Harmful algal blooms (HABs) are increasingly becoming of great concern to water resources worldwide due to indiscriminate waste disposal habits resulting in water pollution and eutrophication. When cyanobacterial cells lyse (burst) they release toxins called microcystins (MCs) that are well known for their hepatotoxicity (causing liver damage) and have been found in eutrophic lakes, rivers, wastewater ponds and other water reservoirs. Prolonged exposure to low concentrated MCs are equally of health importance as they are known to be bioaccumulative and even at such low concentration do exhibit toxic effects to aquatic animals, wildlife and human liver cells. The application of common treatment processes for drinking water sourced from HABs infested reservoirs have the potential to cause algal cell lyses releasing low to higher amounts of MCs in finished water. Trace microcystins in water/tissue can be analyzed and quantified using Liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) following solid-phase extraction (SPE) sample clean-up procedures. However, extracting MCs from algal samples which are rich in chlorophyll pigments and other organic matrices the SPE method suffers a number of drawbacks, including cartridge clogging, long procedural steps and use of larger volumes of extraction solvents. We applied a supported liquid membrane (SLM) based technique as an alternative sample clean-up method for LC-ESI-MS analysis of MCs from both water and algal cells. Four (4) MC variants (MC-RR, -YR, -LR and -WR) from lyophilized cells of Microcystis aeruginosa and water collected from a wastewater pond were identified) and quantified using LC-ESI-MS following a SLM extraction and liquid partitioning step, however, MC-WR was not detected from water extracts. Within 45 min of SLM extraction all studied MCs were extracted and pre-concentrated in approximately 15 ?L of an acceptor phase at an optimal pH 2.02 of the donor phase (sample). The highest total quantifiable intracellular and extracellular MCs were 37.039 0.087 ?g/g DW and 5.123 0.018 ?g/L, respectively. The concentrations of MC-RR were the highest from all samples studied recording maximum values of 21.579 0.066 ?g/g DW and 3.199 0.012 ?g/L for intracellular and extracellular quantities, respectively.

  8. Liquid-Supported Torsion Balance as Gravity Gradiometer: Development and Preliminary Experiments.

    NASA Astrophysics Data System (ADS)

    Keyser, Paul T.

    A liquid-supported torsion balance (LSTB) has been developed which is designed to measure variations in the curvature of the gravity level-surface (i.e., in the "horizontal gravity gradients"). The historical background of LSTB's and gradiometers is reviewed. The theoretical background for an understanding of the essential features of LSTB's is laid. The LSTB is contrasted with the classical fiber-supported torsion balance. The substitution of an electrode array for electrostatic centering and torquing in place of the traditional fiber eliminates many problems associated with fibers and provides an easily-adjustable torsion constant. The apparatus developed is described in detail, with specific reference to temperature-control and liquid-purity issues. We currently obtain temperature stability of (+OR-) 1/2 (mu)(DEGREES)C over a week, with drifts (in the horizontal temperature gradient) as low as 3(mu)(DEGREES)C/hour. The optimal liquid to use in a LSTB is one with a maximum density point, which will minimize the thermal convection currents. In our case the liquid chosen is water. The purification of the water, especially the maintenance of the purity of the free surface, is discussed in detail. The previously-inevitable corrosion of aluminum (an otherwise optimal float material) in water, which seriously compromised the purity of the water, has been studied and its rate reduced by over two orders of magnitude. This allows continuous operation now for at least eight months. Detailed noise analyses are presented and all noise sources are shown to be tractable or small. The noise due to thermal convection currents is presently believed to be the limiting noise source. Progress has been made toward its minimization. Preliminary data are presented and discussed. Plans for future improvements are given.

  9. Computing UV/vis spectra using a combined molecular dynamics and quantum chemistry approach: bis-triazin-pyridine (BTP) ligands studied in solution.

    PubMed

    Höfener, Sebastian; Trumm, Michael; Koke, Carsten; Heuser, Johannes; Ekström, Ulf; Skerencak-Frech, Andrej; Schimmelpfennig, Bernd; Panak, Petra J

    2016-03-01

    We report a combined computational and experimental study to investigate the UV/vis spectra of 2,6-bis(5,6-dialkyl-1,2,4-triazin-3-yl)pyridine (BTP) ligands in solution. In order to study molecules in solution using theoretical methods, force-field parameters for the ligand-water interaction are adjusted to ab initio quantum chemical calculations. Based on these parameters, molecular dynamics (MD) simulations are carried out from which snapshots are extracted as input to quantum chemical excitation-energy calculations to obtain UV/vis spectra of BTP ligands in solution using time-dependent density functional theory (TDDFT) employing the Tamm-Dancoff approximation (TDA). The range-separated CAM-B3LYP functional is used to avoid large errors for charge-transfer states occurring in the electronic spectra. In order to study environment effects with theoretical methods, the frozen-density embedding scheme is applied. This computational procedure allows to obtain electronic spectra calculated at the (range-separated) DFT level of theory in solution, revealing solvatochromic shifts upon solvation of up to about 0.6 eV. Comparison to experimental data shows a significantly improved agreement compared to vacuum calculations and enables the analysis of relevant excitations for the line shape in solution. PMID:26907588

  10. SUPPORTED LIX-84 LIQUID MEMBRANES FOR METAL ION SEPARATION: A STUDY ON METAL ION SORPTION EQUILIBRIUM AND KINETICS

    EPA Science Inventory

    Supported 2-hydroxy-5-nonyl-acetophenone oxime (LIX-84) liquid membranes have potential applications for the removal (or recovery) of copper ions from waste streams. But, the stability of such a liquid membrane remains the major hurdle for its practical applications. Inorganic su...

  11. Membrane-supported liquid-liquid-liquid microextraction combined with anion-selective exhaustive injection capillary electrophoresis-ultraviolet detection for sensitive analysis of phytohormones.

    PubMed

    Huang, Linfang; He, Man; Chen, Beibei; Hu, Bin

    2014-05-23

    A novel method based on off-line membrane-supported liquid-liquid-liquid microextraction (MS-LLLME) combined with on-column anion-selective exhaustive injection (ASEI) capillary electrophoresis-ultraviolet (CE-UV) detection was established for the analysis of seven phytohormones (abscisic acid (ABA), jasmonic acid (JA), 2,4-dichlorophenoxyacetic acid (2,4-D), 1-naphthalene acetic acid (NAA), indole-3-acetic acid (IAA), salicylic acid (SA) and gibberellic acid (GA)). In MS-LLLME, the target phytohormones were extracted from the acid donor phase to the alkaline acceptor phase, and the acceptor solutions were directly analyzed by ASEI-CE-UV. Under the optimal experimental conditions, the analytical performance of the method was evaluated. The limits of detection (LODs) of ABA, JA, 2,4-D, NAA, IAA, SA and GA were determined to be 1.00, 2.21, 0.33, 0.17, 0.67, 0.05 and 16.5ng/mL, respectively. The relative standard deviations (RSDs, n=7) ranged from 4.7% to 12.9%, and the enrichment factors were in the range of 307 to 20,160. The proposed method was successfully applied for the determination of multiple phytohormones in banana, cabbage and cucumber extracts, and ABA, IAA and SA were detected in these samples. The recoveries for the spiked samples were in the range of 79.0 to 116.4%. The proposed method was demonstrated to be suitable for the simultaneous quantification of multiple phytohormones with high sensitivity and good sample cleanup ability. PMID:24720904

  12. SUPPORTED LIQUID CATALYSTS FOR REMOVAL OF HIGH TEMPERATURE FUEL CELL CONTAMINANTS

    SciTech Connect

    Alan W. Weimer; Peter Czerpak; Patrick Hilbert

    2000-01-01

    A novel catalytic synthesis gas oxidation process using molten carbonate salts supported on compatible fluidized iron oxide particles (supported-liquid-phase-catalyst (SLPC) fluidized bed process) was investigated. This process combines the advantages of large scale fluidized bed processing with molten salt bath oxidation. Molten salt catalysts can be supported within porous fluidized particles in order to improve mass transfer rates between the liquid catalysts and the reactant gases. Synthesis gas can be oxidized at reduced temperatures resulting in low NO{sub x} formation while trace sulfides and halides are captured in-situ. Hence, catalytic oxidation of synthesis gas can be carried out simultaneously with hot gas cleanup. Such SLPC fluidized bed processes are affected by inter-particle liquid capillary forces that may lead to agglomeration and de-fluidization of the bed. An understanding of the origin and strength of these forces is needed so that they can be overcome in practice. Process design is based on thermodynamic free energy minimization calculations that indicate the suitability of eutectic Na{sub 2}CO{sub 3}/K{sub 2}CO{sub 3} mixtures for capturing trace impurities in-situ (< 1 ppm SO{sub x} released) while minimizing the formation of NO{sub x}(< 10 ppm). Iron oxide has been identified as a preferred support material since it is non-reactive with sodium, is inexpensive, has high density (i.e. inertia), and can be obtained in various particle sizes and porosities. Force balance modeling has been used to design a surrogate ambient temperature system that is hydrodynamically similar to the real system, thus allowing complementary investigation of the governing fluidization hydrodynamics. The primary objective of this research was to understand the origin of and to quantify the liquid capillary interparticle forces affecting the molten carbonate SLPC fluidized bed process. Substantial theoretical and experimental exploratory results indicate process feasibility. The potential environmental gain from success is enormous, impacting all areas of the world where coal is burned to supply steam or direct industrial heat. Project success may lead to an integrated combustion system providing for simultaneous catalytic oxidation and hot gas cleanup of raw synthesis gas from an upstream coal gasifier.

  13. New support for high-performance liquid chromatography based on silica coated with alumina particles.

    PubMed

    Silveira, Jos Leandro R; Dib, Samia R; Faria, Anizio M

    2014-01-01

    A new material based on silica coated with alumina nanoparticles was proposed for use as a chromatographic support for reversed-phase high-performance liquid chromatography. Alumina nanoparticles were synthesized by a sol-gel process in reversed micelles composed of sodium bis(2-ethylhexyl)sulfosuccinate, and the support material was formed by the self-assembly of alumina layers on silica spheres. Spectroscopic and (29)Si nuclear magnetic resonance results showed evidence of chemical bonds between the alumina nanoparticles and the silica spheres, while morphological characterizations showed that the aluminized silica maintained the morphological properties of silica desired for chromatographic purposes after alumina incorporation. Stability studies indicated that bare silica showed high dissolution (~83%), while the aluminized silica remained practically unchanged (99%) after passing one liter of the alkaline mobile phase, indicating high stability under alkaline conditions. The C18 bonded aluminized silica phase showed great potential for use in high-performance liquid chromatography to separate basic molecules in the reversed-phase mode. PMID:24521917

  14. Summary of Liquid Propulsion System Needs in Support of the Constellation Program

    NASA Technical Reports Server (NTRS)

    Lorier, Terry; Sumrall, Phil; Baine, Michael

    2008-01-01

    In January 2004, the President of the United States established the Vision for Space Exploration (VSE) to complete the International Space Station, retire the Space Shuttle and develop its replacement, and expand the human presence on the Moon as a stepping stone to human exploration of Mars and worlds beyond. In response, NASA developed the Constellation Program, consisting of the components shown in Figure 1. This paper will summarize the manned spaceflight liquid propulsion system needs in support of the Constellation Program over the next 10 years. It will address all liquid engine needs to support human exploration from low Earth orbit (LEO) to the lunar surface, including an overview of engines currently under contract, those baselined but not yet under contract, and those propulsion needs that have yet to be initiated. There may be additional engine needs for early demonstrators, but those will not be addressed as part of this paper. Also, other portions of the VSE architecture, including the planned Orion abort test boosters and the Lunar Precursor Robotic Program, are not addressed here as they either use solid motors or are focused on unmanned elements of returning humans to the Moon.

  15. Advanced Supported Liquid Membranes for Carbon Dioxide Control in Cabin Applications

    NASA Technical Reports Server (NTRS)

    Wickham, David T.; Gleason, Kevin J.; Engel, Jeffrey R.; Chullen, Cinda

    2016-01-01

    The development of new, robust, life support systems is critical to NASA's continued progress in space exploration. One vital function is maintaining the carbon dioxide (CO2) concentration in the cabin at levels that do not impair the health or performance of the crew. The CO2 removal assembly (CDRA) is the current CO2 control technology on-board the International Space Station (ISS). Although the CDRA has met the needs of the ISS to date, the repeated cycling of the molecular sieve sorbent causes it to break down into small particles that clog filters or generate dust in the cabin. This reduces reliability and increases maintenance requirements. Another approach that has potential advantages over the current system is a membrane that separates CO2 from air. In this approach, cabin air contacts one side of the membrane while other side of the membrane is maintained at low pressure to create a driving force for CO2 transport across the membrane. In this application, the primary power requirement is for the pump that creates the low pressure and then pumps the CO2 to the oxygen recovery system. For such a membrane to be practical, it must have high CO2 permeation rate and excellent selectivity for CO2 over air. Unfortunately, conventional gas separation membranes do not have adequate CO2 permeability and selectivity to meet the needs of this application. However, the required performance could be obtained with a supported liquid membrane (SLM), which consists of a microporous material filled with a liquid that selectively reacts with CO2 over air. In a recently completed Phase II SBIR project, Reaction Systems, Inc. fabricated an SLM that is very close to meeting permeability and selectivity objectives for use in the advanced space suit portable life support system. This paper describes work carried out to evaluate its potential for use in spacecraft cabin application.

  16. The application of supported liquid extraction in the analysis of benzodiazepines using surface enhanced Raman spectroscopy.

    PubMed

    Doctor, Erika L; McCord, Bruce

    2015-11-01

    Benzodiazepines are among the most frequently prescribed medicines for anxiety disorders and are present in many toxicological screens. These drugs are often administered in the commission of drug facilitated sexual assaults due their effects on the central nervous system. Due to the potency of the drugs, only small amounts are usually given to victims; therefore, the target detection limit for these compounds in biological samples has been set at 50 ng/mL. Currently the standard screening method for detection of this class of drug is the immunoassay; however, screening methods that are more sensitive and selective than immunoassays are needed to encompass the wide range of structural variants of this class of compounds. Surface enhanced Raman spectroscopy (SERS) can be highly sensitive and has been shown to permit analysis of various benzodiazepines with limits of detection as low as 6 ng/mL. This technique permits analytical results in less than 2 min when used on pure drug samples. For biological samples, a key issue for analysis by SERS is removal of exogenous salts and matrix components. In this paper we examine supported liquid extraction as a useful preparation technique for SERS detection. Supported liquid extraction has many of the benefits of liquid-liquid extraction along with the ability to be automated. This technique provides a fast and clean extraction for benzodiazepines from urine at a pH of 5.0, and does not produce large quantities of solvent waste. To validate this procedure we have determined figures of merit and examined simulated urine samples prepared with commonly appearing interferences. It was shown that at a pH 5.0 many drugs that are prevalent in urine samples can be removed, permitting a selective detection of the benzodiazepine of interest. This technique has been shown to provide rapid (less than 20 min), sensitive, and specific detection of benzodiazepines with limits of detection between 32 and 600 ng/mL and dynamic range of 32-25,000 ng/mL. It provides the forensic community with a sensitive and specific screening technique for the detection of benzodiazepines in drug facilitated assault cases. PMID:26452911

  17. Supported Phospholipid Bilayer Defects Created by a Cation or Anion of a Room-Temperature Ionic Liquid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this work, the independent effects on a supported phospholipid bilayer (SPB) caused by a cation and anion of a room-temperature ionic liquid (RT-IL) were studied via atomic force microscopy (AFM). The supported phospholipid bilayer was composed only of 1,2-dielaidoylphosphatidylcholine (DEPC) an...

  18. Augmenting Microbial Fuel Cell power by coupling with Supported Liquid Membrane permeation for zinc recovery.

    PubMed

    Fradler, Katrin R; Michie, Iain; Dinsdale, Richard M; Guwy, Alan J; Premier, Giuliano C

    2014-05-15

    Simultaneous removal of organic and zinc contamination in parallel effluent streams using a Microbial Fuel Cell (MFC) would deliver a means of reducing environmental pollution whilst also recovering energy. A Microbial Fuel Cell system has been integrated with Supported Liquid Membrane (SLM) technology to simultaneously treat organic- and heavy metal containing wastewaters. The MFC anode was fed with synthetic wastewater containing 10mM acetate, the MFC cathode chambers were fed with 400mgL(-1) Zn(2+) and this then acted as a feed phase for SLM extraction. The MFC/SLM combination produces a synergistic effect which enhances the power performance of the MFC significantly; 0.233mW compared to 0.094mW in the control. It is shown that the 1657mV difference between the MFC/SLM system and the MFC control is attributable to the lower cathode pH in the integrated system experiment, the consequent lower activation overpotential and higher oxygen reduction potential. The change in the substrate removal efficiency and Coulombic Efficiency (CE) compared to controls is small. Apart from the electrolyte conductivity, the conductivities of the bipolar and liquid membrane were also found to increase during operation. The diffusion coefficient of Zn(2+) through the liquid membrane in the MFC/SLM (4.26*10(-10)m(2)s(-1)) is comparable to the SLM control (5.41*10(-10)m(2)s(-1)). The system demonstrates that within 72h, 934% of the zinc ions are removed from the feed phase, hence the Zn(2+) removal rate is not significantly affected and is comparable to the SLM control (961%), while MFC power output is significantly increased. PMID:24602866

  19. Hollow-fiber supported liquid membrane (HFSLM) for the separation of lanthanides and actinides

    SciTech Connect

    Mohapatra, P.K.; Ansari, S.A.; Bhattacharyya, A.; Manchanda, V.K.; Patil, C.B.

    2008-07-01

    The transport behavior of Nd(III) was investigated using hollow-fiber supported liquid membranes (HFSLM) from an acidic feed solution using N,N,N',N'-tetraoctyl-diglycolamide (TODGA) in normal paraffinic hydrocarbon (NPH) as the carrier. Near quantitative transport (>99%) of Nd(III) from 500 mL of feed containing 1 g/L Nd in 3.5 M HNO{sub 3} was possible in about 45 minutes. Quantitative transport time increased when the volume or Nd(III ) concentration in the feed was increased. The liquid membrane had excellent stability as indicated by eight consecutive runs that gave consistent transport rates. The HFSLM data using Cyanex- 301 in n-dodecane as carrier extractant for the lanthanide-actinide separation with the feed solution 1 M NaNO{sub 3} at pH 3.5 and stripping solution 0.01 M EDTA at a pH 3.5 were promising. (authors)

  20. Some methods of human liquid and solid wastes utilization in bioregenerative life support systems

    NASA Astrophysics Data System (ADS)

    Tikhomirova, N. A.; Ushakova, S. Á.; Tikhomirov, A. Á.; Zolotukhin, I. G.; Gribovskaya, I. V.; Gros, J. B.

    The possibility of stepwise utilization of human liquid and solid wastes with the purpose of an increase of a closure degree of bioregenerative life support systems BLSS and sodium chloride inclusion in the organic matter turnover was investigated On the first stage urine and faeces were subjected to oxidation by Yu A Kudenko physicochemical method On the next stage the products of human liquid and solid wastes oxidation were used for roots nutrition of wheat grown by substrate culture method Soil-like substrate the technology of which was described earlier was used as a substrate After the wheat cultivation the irrigational solution and the solution obtained in the result of substrate washing containing mineral elements not absorbed by the plants were used for cultivation of salt-tolerant Salicornia europaea plants The above-ground biomass of these vegetables can be used as a food and roots washed from dissoluble mineral elements can be added to the soil-like substrate Four consecutive wheat and Salicornia europaea vegetations were cultivated In the result of this complex technology of wheat and Salicornia europaea cultivation the soil-like substrate salinization by NaCl introduced into the irrigational solution together with the products of urine oxidation has considerably decreased

  1. Transport of europium through supported liquid membrane containing dihexyl-N,N-diethyl-carbamoyl-methyl-phosphonate

    SciTech Connect

    Nakamura, Shigeto; Akiba, Kenichi )

    1989-12-01

    The transport of europium has been studied through a supported liquid membrane (SLM) impregnated with dihexyl-N,N-diethyl-carbamoyl-methyl-phosphonate (CMP). Europium was effectively extracted from the perchlorate solution into SLM, but was insufficiently stripped to a dilute acid solution. The addition of 1-decanol improved the stripping process, and quantitative transport of europium was achieved. By the combination of two SLM systems consisting of diisodecylphosphoric acid and CMP, europium was transported from the feed solution (0.1 M HNO{sub 3}) through the intermediate solution (1 M HClO{sub 4} + 4 M NaClO{sub 4}) to the product solution (0.1 M HNO{sub 3}) and effectively concentrated by a factor of about 20.

  2. Computational Fluid Dynamics in Support of the SNS Liquid Mercury Thermal-Hydraulic Analysis

    SciTech Connect

    Siman-Tov, M.; Wendel, M.W.; Yoder, G.L.

    1999-11-14

    Experimental and computational thermal-hydraulic research is underway to support the liquid mercury target design for the Spallation Neutron Source (SNS) facility. The SNS target will be subjected to internal nuclear heat generation that results from pulsed proton beam collisions with the mercury nuclei. Recirculation and stagnation zones within the target are of particular concern because of the likelihood that they will result in local hot spots and diminished heat removal from the target structure. Computational fluid dynamics (CFD) models are being used as a part of this research. Recent improvements to the 3D target model include the addition of the flow adapter which joins the inlet/outlet coolant pipes to the target body and an updated heat load distribution at the new baseline proton beam power level of 2 MW. Two thermal-hydraulic experiments are planned to validate the CFD model.

  3. The application of supported liquid membrane separators to alkaline secondary batteries

    SciTech Connect

    Pemsler, J.P.; Demsey, M.D.

    1983-10-01

    A new separator technology under development utilizes the highly specific transport properties of select organic reagents to provide what is, at least in principal, the ideal alkaline battery, separator. In the case of Ni-Zn cells, by providing a membrane that transports hydroxyl ions and rejects zincate ions the possibility of dendrite shorting is eliminated and, furthermore, attendant benefits may be obtained in zinc shape changes by controlling water transport during charge and discharge. Laboratory Ni-Zn test cells incorporating supported liquid membrane battery separators have been cycled extensively. Cells routinely operate over 100 cycles at moderate current densities. Possible benefits to other alkaline systems such as Ni-Cd and Ag-Zn are also discussed.

  4. Attraction of mesoscale objects on the surface of a thin elastic film supported on a liquid.

    PubMed

    Chakrabarti, Aditi; Chaudhury, Manoj K

    2015-02-17

    We study the interaction of two parallel rigid cylinders on the surface of a thin elastic film supported on a pool of liquid. The excess energy of the surface due to the curvature of the stretched film induces attraction of the cylinders that can be quantified by the variation of their gravitational potential energies as they descend into the liquid while still floating on the film. Although the experimental results follow the trend predicted from the balance of the gravitational and elastic energies of the system, they are somewhat underestimated. The origin of this discrepancy is the hysteresis of adhesion between the cylinder and the elastic film that does not allow the conversion of the total available energy into gravitational potential energy, as some part of it is recovered in stretching the film behind the cylinders while they approach each other. A modification of the model accounting for the effects of adhesion hysteresis improves the agreement between theoretical and experimental results. The contribution of the adhesion hysteresis can be reduced considerably by introducing a thin hydrogel layer atop the elastic film that enhances the range of attraction of the cylinders (as well as rigid spheres) in a dramatic way. Morphological instabilities in the gel project corrugated paths to the motion of small spheres, thus leading to a large numbers of particles to aggregate along their defects. These observations suggest that a thin hydrogel layer supported on a deformable elastic film affords an effective model system to study elasticity and defects mediated interaction of particles on its surface. PMID:25069091

  5. Effect of Ammonium- and Phosphonium-Based Ionic Liquids on the Separation of Lactic Acid by Supported Ionic Liquid Membranes (SILMs)

    PubMed Central

    Matsumoto, Michiaki; Panigrahi, Abhishek; Murakami, Yuuki; Kondo, Kazuo

    2011-01-01

    Biodegradable polymers have attracted much attention from an environmental point of view. Optically pure lactic acid that can be prepared by fermentation is one of the important raw materials for biodegradable polymer. The separation and purification of lactic acid from the fermentation broth are the major portions of the production costs. We proposed the application of supported ionic liquid membranes to recovering lactic acid. In this paper, the effect of ionic liquids, such as Aliquat 336, CYPHOS IL-101, CYPHOS IL-102, CYPHOS IL-104, CYPHOS IL-109 and CYPHOS IL-111 on the lactic acid permeation have been studied. Aliquat 336, CYPHOS IL-101 and CYPHOS IL-102 were found to be the best membrane solvents as far as membrane stability and permeation of lactic acid are concerned. CYPHOS IL-109 and CYPHOS IL-111 were found to be unsuitable, as they leak out from the pores of the supported liquid membrane (SLM), thereby allowing free transport of lactic acid as well as hydrochloric acid. CYPHOS IL-102 was found to be the most adequate (Permeation rate = 60.41%) among these ionic liquids as far as the separation of lactic acid is concerned. The permeation mechanisms, by which ionic liquid-water complexes act as the carrier of lactate and hydrochloric acid, were proposed. The experimental permeation results have been obtained as opposed to the expected values from the solution-diffusion mechanism. PMID:24957613

  6. Some methods for human liquid and solid waste utilization in bioregenerative life-support systems.

    PubMed

    Ushakova, S A; Zolotukhin, I G; Tikhomirov, A A; Tikhomirova, N A; Kudenko, Yu A; Gribovskaya, I V; Balnokin, Yu; Gros, J B

    2008-12-01

    Bioregenerative life-support systems (BLSS) are studied for developing the technology for a future biological life-support system for long-term manned space missions. Ways to utilize human liquid and solid wastes to increase the closure degree of BLSS were investigated. First, urine and faeces underwent oxidation by Kudenko's physicochemical method. The products were then used for root nutrition of wheat grown by the soil-like substrate culture method. Two means of eliminating sodium chloride, introduced into the irrigation solution together with the products of urine oxidation, were investigated. The first was based on routine electrodialysis of irrigation water at the end of wheat vegetation. Dialysis eliminated about 50% of Na from the solution. This desalinization was performed for nine vegetations. The second method was new: after wheat cultivation, the irrigation solution and the solution obtained by washing the substrate containing mineral elements not absorbed by the plants were used to grow salt-tolerant Salicornia europaea L. plants (saltwort). The above-ground biomass of this plant can be used as a food, and roots can be added to the soil-like substrate. Four consecutive wheat and Salicornia vegetations were cultivated. As a result of this wheat and Salicornia cultivation process, the soil-like substrate salinization by NaCl were considerably decreased. PMID:18581263

  7. Poly(dimethylsiloxane)-supported ionogels with a high ionic liquid loading.

    PubMed

    Horowitz, Ariel I; Panzer, Matthew J

    2014-09-01

    The immiscibility of poly(dimethylsiloxane) (PDMS) and ionic liquids (ILs) was overcome to create PDMS-supported IL gels (ionogels) with IL loadings of up to 80% by mass through a simple sol-gel reaction at room temperature. By stirring a mixture of a functionalized PDMS oligomer, formic acid, and an IL (or lithium-in-IL solution), a resin was formed that could be cast to create a freestanding, flexible ionogel. PDMS-supported ionogels exhibited favorable ionic conductivity (ca. 3?mS?cm(-1)) and excellent mechanical behavior (elastic modulus: ca. 60?kPa; fatigue life: >5000 cycles; mechanically stable at temperatures up to 200?C). The activation energy of ionic conductivity was shown to be nearly identical for the ionogel and the neat IL, in contrast to ionogel systems wherein the scaffold material is miscible with the IL. This similarity indicates that IL/scaffold chemical interactions are key to the understanding of ionogel electrical performance, especially at elevated temperatures. PMID:25044479

  8. Silica-particle-supported zwitterionic polymer monolith for microcolumn liquid chromatography.

    PubMed

    An, Ran; Weng, Qianfeng; Li, Jinxiang

    2014-10-01

    A silica-particle-supported zwitterionic polymeric monolithic column, shortened as supported column (S-column), was prepared by the in situ polymerization of methacrylic acid, ethylene dimethacrylate, and 2-(dimethylamino)ethyl methacrylate in the presence of a ternary porogenic solvent containing water, methanol, and cyclohexanol in a 250 μm id fused-silica capillary prepacked with 5 μm bare silica particles. In the S-column, a thin layer of the polymers was formed around the silica particles in the form of nanoglobules, leaving the interstitial spaces between the particles free for liquid flow. The effects of the preparation conditions on the morphology of the monolith were investigated by scanning electron microscopy and backpressure measurements. The selected volumetric ratio of porogens, monomer concentration, polymerization time, and temperature are 1:1:8 (water/methanol/cyclohexanol), 25% v/v, 5 h, and 60°C, respectively. The S-column was evaluated by comparison with its conventional organic counterpart in terms of morphology, mechanical stability, permeability, swelling-shrinking behavior, capacity, and efficiency. The results demonstrate that the S-column is superior to its counterpart in all the terms with the exception of permeability. The above merits and zwitterionic property of the S-column were further confirmed by separate separations of four inorganic anions and three organic cations. PMID:25044794

  9. Diffusivity and solubility of organic solutes in supported liquid crystal membranes.

    PubMed

    Han, Sangil; Martin, Stephen M

    2009-09-24

    The electro-optical properties of thermotropic liquid crystalline (LC) materials have been the subject of significant research effort due to their well-established applications in display technology; however, relatively little work has been done concerning the transport of dissolved solutes in LC phases, limiting their potential use in applications including chemical separation and sensing. Supported liquid crystal membranes were synthesized by impregnating porous cellulose nitrate (CN) membranes with 4-cyano-4'-octylbiphenyl (8CB) from chloroform solutions under vacuum. The resulting membranes were stable under aqueous conditions. Measurements of the 8CB-CN membrane transport properties were performed at 38 degrees C (nematic) and 44 degrees C (isotropic) for 11 aromatic solutes, including positional isomers, in aqueous solution. Solute diffusivity and solubility was calculated using a time-lag technique based on the study of the transient (unsteady state) and steady-state permeation regimes. The solubility and diffusivity of aqueous aromatic solutes in 8CB LCs depended significantly on intra- and intermolecular hydrogen bonding, and more specifically the number of hydrogen-bonding sites on a solute that are available for interactions with the aqueous and LC phases. In the nematic phase of 8CB, shape specific affinity was observed for para isomers and other rodlike solutes. A decreased activation energy for diffusion was observed at the isotropic to nematic phase transition for o-hydroxybenzoic acid, as expected based on the increased order in the nematic phase. Permeation selectivities for the separation of positional isomers by the 8CB-CN membranes indicated high selectivity only for the hydroxybenzoic acid isomers, due to the propensity of o-hydroxybenzoic acid to form intramolecular hydrogen bonds. PMID:19715323

  10. A polymerized ionic liquid-supported B12 catalyst with a ruthenium trisbipyridine photosensitizer for photocatalytic dechlorination in ionic liquids.

    PubMed

    Zhang, Wei; Shimakoshi, Hisashi; Houfuku, Noriyuki; Song, Xi-Ming; Hisaeda, Yoshio

    2014-10-01

    By immobilizing a B12 complex and a Ru(ii) trisbipyridine photosensitizer in a polymerized ionic liquid (PIL), a visible light-driven photocatalyst was developed. The synthesized copolymer was characterized by GPC and DLS, and using UV-vis absorption spectra and luminescence spectra. The Ru(ii) trisbipyridine photosensitizer in the copolymer showed an enhanced emission compared to that of the monomer in the ionic liquid, 1-butyl-4-methylimidazolium bis(trifluoromethanesulfonyl)amide ([C4mim][NTf2]). Formation of the Co(i) species of the B12 complex in the copolymer was confirmed by the UV-vis spectral change in [C4mim][NTf2] containing a sacrificial reductant (triethanolamine) under irradiation with visible light. The copolymer showed a high photocatalytic activity in various ionic liquids for 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT) dechlorination with ?99% conversion after visible light irradiation for 2 h. Furthermore, both the B12 catalyst and photosensitizer in the polymer were easily recycled for use with the ionic liquid solvent without any loss of catalytic activity. PMID:25118045

  11. An electrochemical gas sensor based on paper supported room temperature ionic liquids.

    PubMed

    Dossi, Nicolò; Toniolo, Rosanna; Pizzariello, Andrea; Carrilho, Emanuel; Piccin, Evandro; Battiston, Simone; Bontempelli, Gino

    2012-01-01

    A sensitive and fast-responding membrane-free amperometric gas sensor is described, consisting of a small filter paper foil soaked with a room temperature ionic liquid (RTIL), upon which three electrodes are screen printed with carbon ink, using a suitable mask. It takes advantage of the high electrical conductivity and negligible vapour pressure of RTILs as well as their easy immobilization into a porous and inexpensive supporting material such as paper. Moreover, thanks to a careful control of the preparation procedure, a very close contact between the RTIL and electrode material can be achieved so as to allow gaseous analytes to undergo charge transfer just as soon as they reach the three-phase sites where the electrode material, paper supported RTIL and gas phase meet. Thus, the adverse effect on recorded currents of slow steps such as analyte diffusion and dissolution in a solvent is avoided. To evaluate the performance of this device, it was used as a wall-jet amperometric detector for flow injection analysis of 1-butanethiol vapours, adopted as the model gaseous analyte, present in headspace samples in equilibrium with aqueous solutions at controlled concentrations. With this purpose, the RTIL soaked paper electrochemical detector (RTIL-PED) was assembled by using 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide as the wicking RTIL and printing the working electrode with carbon ink doped with cobalt(II) phthalocyanine, to profit from its ability to electrocatalyze thiol oxidation. The results obtained were quite satisfactory (detection limit: 0.5 μM; dynamic range: 2-200 μM, both referring to solution concentrations; correlation coefficient: 0.998; repeatability: ±7% RSD; long-term stability: 9%), thus suggesting the possible use of this device for manifold applications. PMID:22076475

  12. Carbon-supported ionic liquids as innovative adsorbents for CO? separation from synthetic flue-gas.

    PubMed

    Erto, Alessandro; Silvestre-Albero, Ana; Silvestre-Albero, Joaqun; Rodrguez-Reinoso, Francisco; Balsamo, Marco; Lancia, Amedeo; Montagnaro, Fabio

    2015-06-15

    Fixed-bed thermodynamic CO2 adsorption tests were performed in model flue-gas onto Filtrasorb 400 and Nuchar RGC30 activated carbons (AC) functionalized with [Hmim][BF4] and [Emim][Gly] ionic liquids (IL). A comparative analysis of the CO2 capture results and N2 porosity characterization data evidenced that the use of [Hmim][BF4], a physical solvent for carbon dioxide, ended up into a worsening of the parent AC capture performance, due to a dominating pore blocking effect at all the operating temperatures. Conversely, the less sterically-hindered and amino acid-based [Emim][Gly] IL was effective in increasing the AC capture capacity at 353 K under milder impregnation conditions, the beneficial effect being attributed to both its chemical affinity towards CO2 and low pore volume reduction. The findings derived in this work outline interesting perspectives for the application of amino acid-based IL supported onto activated carbons for CO2 separation under post-combustion conditions, and future research efforts should be focused on the search for AC characterized by optimal pore size distribution and surface properties for IL functionalization. PMID:25710387

  13. Troponin T immunosensor based on liquid crystal and silsesquioxane-supported gold nanoparticles.

    PubMed

    Zapp, Eduardo; da Silva, Paulo Srgio; Westphal, Eduard; Gallardo, Hugo; Spinelli, Almir; Vieira, Iolanda Cruz

    2014-09-17

    A nanostructured immunosensor based on the liquid crystal (E)-1-decyl-4-[(4-decyloxyphenyl)diazenyl]pyridinium bromide (Br-Py) and gold nanoparticles supported by the water-soluble hybrid material 3-n-propyl-4-picolinium silsesquioxane chloride (AuNP-Si4Pic(+)Cl(-)) was built for the detection of troponin T (cTnT), a cardiac marker for acute myocardial infarction (AMI). The functionalized nanostructured surface was used to bind anti-cTnT monoclonal antibodies through electrostatic interaction. The immunosensor (ab-cTnT/AuNP-Si4Pic(+)Cl(-)/Br-Py/GCE) surface was characterized by microscopy techniques. The electrochemical behavior of the immunosensor was studied by cyclic voltammetry and electrochemical impedance spectroscopy. A calibration curve was obtained by square-wave voltammetry. The immnunosensor provided a limit of detection of 0.076 ng mL(-1) and a linear range between 0.1 and 0.9 ng mL(-1) (appropriate for AMI diagnosis). PMID:25111622

  14. Stability and efficiency of supported liquid membranes in electromembrane extraction--a link to solvent properties.

    PubMed

    Seip, Knut Fredrik; Faizi, Moheba; Vergel, Cristina; Gjelstad, Astrid; Pedersen-Bjergaard, Stig

    2014-03-01

    The current work presents a large systematic screening of 61 possible organic solvents used as supported liquid membranes (SLM) in electromembrane extraction (EME). For each organic solvent, recovery, current across the SLM, and stability considerations have been investigated and correlated to relevant solvent properties through partial least square regression analysis. The five unpolar basic drugs pethidine, haloperidol, methadone, nortriptyline, and loperamide were used as model analytes. Efficient EME solvents were found to have a low water solubility (<0.5 g L(-1)) and belonged to cluster 2 of a Kamlet-and-Taft-based solvent classification system (high dipole moments and proton acceptor properties). These parameters were especially found in nitroaromatic compounds and ketones. Small molecules with low log P value and high water solubility were unsuitable, as they tended to give unstable extractions, caused by a high current across the SLM. This was often combined with substantial solvent-related interferences and the generation of an electroosmotic flow across the SLM, with resulting acceptor solution expansion. Large molecules with a high log P value were classified as inefficient. For these solvents, no current was measured across the SLM and no analytes were extracted. This is the first time systematic knowledge on the SLM in EME has been gathered and investigated, and the presented results could be highly beneficial for future development and optimization of EME. PMID:24136254

  15. Selective removal and recovery of Black B reactive dye from simulated textile wastewater using the supported liquid membrane process.

    PubMed

    Harruddin, Norlisa; Othman, Norasikin; Ee Sin, Andeline Lim; Raja Sulaiman, Raja Norimie

    2015-01-01

    Effluent containing colour/dyes, especially reactive dyes, becomes a great concern of wastewater treatment because it is toxic to human life and aquatic life. In this study, reactive dye of Black B was separated using the supported liquid membrane process. Commercial polypropylene membrane was used as a support of the kerosene-tridodecylamine liquid membrane. Several parameters were tested and the result showed that almost 100% of 70?ppm Black B was removed and 99% of 70?ppm Black B was recovered at pH 2 of the feed phase containing 0.00001?M Na2SiO3, flow rate of 150?ml/min and 0.2?M NaOH. The membrane support also remained stable for up to 36 hours under an optimum condition. PMID:25514128

  16. Modeling of the mass transfer rates of metal ions across supported liquid membranes. 2: Comparison between theory and experiment

    SciTech Connect

    Elhassadi, A.A.; Do, D.D.

    1999-02-01

    The model equations developed in Part 1 were tested using experimental data reported in the literature and produced in this work. It was found that uranium(VI) and thorium(IV) can be selectively separated and concentrated using supported liquid membranes. Depending on the way the liquid membranes are designed, the selectivity toward a specific metal can be predetermined. The effect of the ratio of the effective diffusivity to bulk diffusivity in free solution was found to behave with the same characteristic of systems of preferentially adsorbed solutes.

  17. Interaction of an ionic liquid with a supported phospholipid bilayer is lipid-dependent

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Liquid salts, commonly called ionic liquids, are used as solvents to conduct transformation of vegetable oils into new products. These reactions are often catalyzed via immobilized enzymes. However, some enzymes were found to lose activity and are in need of some protection. Phospholipid bilayers...

  18. Microextraction of mebendazole across supported liquid membrane forced by pH gradient and electrical field.

    PubMed

    Eskandari, Mahboube; Yamini, Yadollah; Fotouhi, Lida; Seidi, Shahram

    2011-04-01

    In the present study, extraction of mebendazole across a supported-liquid membrane (SLM) was performed based on two different driving forces: (1) pH gradient over the SLM, and (2) electrical field sustained over the SLM. The extracted drug concentration was studied using reversed-phase HPLC-UV. At passive extraction conditions, mebendazole was extracted from alkaline samples (0.01 mmol L(-1) NaOH) into 1-undecanol immobilized in the pores of a porous hollow fiber of polypropylene (SLM), and then transported into 25 ?L of 100mM HCl as the acceptor solution. Under electrokinetic migration conditions, mebendazole transported under applied voltage from acidic solutions (100 mmol L(-1) HCl) through 2-nitrophenyl octyl ether (NPOE) immobilized in the pores of hollow fiber, into 25 ?L of 100 mmol L(-1) HCl as the acceptor solution. The effects of several factors including the nature of organic solvent, pH of donor and acceptor solutions, extraction time and stirring speed on the extraction efficiency of the drug were investigated and optimized. Under optimal conditions, preconcentration factors (PF) of 211 and 190 were obtained for the drug based on passive transport and electromembrane extraction (EME), respectively. Also, linear range of 0.5-1000 ?g L(-1) with estimation of coefficient higher than 0.994 was obtained for both of the proposed methods. The results showed that EME has higher speed in comparison with simple passive transport. The methods were successfully applied to extract mebendazole from plasma and urine samples and satisfactory results were obtained. PMID:21211924

  19. Perspective technologies for equipment and liquidation of working faces with heavy mechanized supports

    SciTech Connect

    Pavliska, J.; Polak, J.

    1994-12-31

    Ostrava-Karvind coal mines (OKD) situated at the south part of the Silesian basin near the boarder with Poland is the biggest Czech basin with underground mining. It produced both coke and energetic coal with maximum output of 24 mil. t in 1980. Since then the output has been dropping down to 14 mil. t from 10 collieries with 39,000 underground workers in 1993. The only mining method is longwall mining with caving or less commonly with packs. Last year 79% of coal was extracted from faces equipped by mechanized supports and shearer loaders or ploughs. The face complex also involves face and gathering chain conveyors, breaker and hydraulic and power supply units with wirings. 1,500--4,000 t of material is necessary to transport to the face, to assemble there, and after its exploitation to move it back to the surface or to the another prepared face. Most of equipment is transported to the face from the surface. The labor requirement for the process is very high and depends mainly on the technical equipment of transport routes. The methods of coal seams exploitation in OKD under geologically sophisticated conditions only very seldom allows preparation of faces with a sufficient length and life. That is why 40% of 70 working faces are in the phase of equipping or liquidation. Those non-productive stages shorten machine available time of very expensive mining complexes and therefore it is desirable to prepare and implement them to ensure the shortest time possible, the lowest labor requirements and the highest output.

  20. Liquid phase methanol LaPorte Process Development Unit: Modification, operation, and support studies

    SciTech Connect

    Not Available

    1991-02-28

    The LPMEOH process was conceived and patented by Chem Systems Inc. in 1975. Initial research and studies on the process focused on two distinct modes of operation. The first was a liquid fluidized mode with relatively large catalyst pellets suspended in a fluidizing liquid, and the second was an entrained (slurry) mode with fine catalyst particles slurried in an inert liquid. The development of both operating modes progressed in parallel from bench scale reactors, through an intermediate scale lab PDU, and then to the LaPorte PDU in 1984. The slurry mode of operation was ultimately chosen as the operating mode of choice due to its superior performance.

  1. Polymeric ionic liquid and carbon black composite as a reusable supporting electrolyte: modification of the electrode surface.

    PubMed

    Yoo, Seung Joon; Li, Long-Ji; Zeng, Cheng-Chu; Little, R Daniel

    2015-03-16

    One of the major impediments to using electroorganic synthesis is the need for large amounts of a supporting electrolyte to ensure the passage of charge. Frequently this causes separation and waste problems. To address these issues, a polymeric ionic liquid-Super?P carbon black composite has been formulated. The system enables electrolyses to be performed without adding an additional supporting electrolyte, and its efficient recovery and reuse. In addition, the ability of the composite to modify the electrode surface in?situ leads to improved kinetics. A practical consequence is that one can decrease catalyst loading without sacrificing efficiency. PMID:25619992

  2. Determination of benzodiazepines in ante-mortem and post-mortem whole blood by solid-supported liquid-liquid extraction and UPLC-MS/MS.

    PubMed

    Sauve, E N; Langdegrd, M; Ekeberg, D; iestad, A M L

    2012-02-01

    A solid-supported liquid-liquid extraction ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the determination of benzodiazepines commonly found in Norway, for use in cases with suspected driving impairment and autopsy cases by analysis of human whole blood samples. The following compounds were included: alprazolam, bromazepam, clonazepam, diazepam, flunitrazepam, lorazepam, midazolam, nitrazepam, nordiazepam (metabolite of diazepam), oxazepam and phenazepam. Aliquots of 500 ?L whole blood were added 500 ?L of borate buffer pH 11 and extracted by solid-supported liquid-liquid extraction on ChemElut() columns using three times 2.5 mL of methyl tert-butyl ether. Deuterated analogues were used as internal standards (IS) for all analytes, except for midazolam, phenazepam and bromazepam which had no commercially available deuterated analogues at the time the method was developed, and therefore used diazepam-d(5), flunitrazepam-d(7) and nitrazepam-d(5), respectively. The analytes were separated using UPLC with a 2.1100 mm BEH C(18)-column, 1.7 ?m particle size, and quantified by MS/MS using multiple reaction monitoring (MRM) in positive mode. Two transitions were used for the analytes and one transition for the IS. The run time of the method was 8 min including equilibration time. The concentrations of the benzodiazepines in the method span a broad range varying from the lowest concentration of 0.005 ?M for flunitrazepam to the highest of 20 ?M for oxazepam. The calibration curves of extracted whole blood standards were fitted by second-order calibration curves weighted 1/x, with R(2) values ranging from 0.9981 to 0.9998. The intermediate precision had a CV (%) ranging between 2 and 19%. Recoveries of the analytes were from 71 to 96%. The LLOQs for the analytes varied from 0.0006 to 0.075 ?M and the LODs from 0.005 to 3.0 nM. Matrix effects were studied by post extraction addition and found to be between 95 and 104% when calculated against an internal standard. A comparison with two other LC-MS methods was performed during method validation. Good correlation was seen for all analytes. The method has been running on a routine basis for several years, and has proven to be very robust and reliable with good results for external quality samples. The method also meets the requirements of the legislative limits for driving under the influence of non-alcohol drugs to be introduced in the Norwegian legislative system from 2012. PMID:22119506

  3. Piping support system for liquid-metal fast-breeder reactor

    DOEpatents

    Brussalis, Jr., William G. (Forward Township, Washington County, PA)

    1984-01-01

    A pipe support consisting of a rigid link pivotally attached to a pipe and an anchor, adapted to generate stress or strain in the link and pipe due to pipe thermal movement, which stress or strain can oppose further pipe movement and generally provides pipe support. The pipe support can be used in multiple combinations with other pipe supports to form a support system. This support system is most useful in applications in which the pipe is normally operated at a constant elevated or depressed temperature such that desired stress or strain can be planned in advance of pipe and support installation. The support system is therefore especially useful in steam stations and in refrigeration equipment.

  4. Effects of Silica Nanoparticle Supported Ionic Liquid as Additive on Thermal Reversibility of Human Carbonic Anhydrase II

    PubMed Central

    Fallahbagheri, Azadeh; Saboury, Ali Akbar; Ma'mani, Leila; Taghizadeh, Mohammad; Khodarahmi, Reza; Ranjbar, Samira; Bohlooli, Mousa; Shafiee, Abbas; Foroumadi, Alireza; Sheibani, Nader; Moosavi-Movahedi, Ali Akbar

    2013-01-01

    Silica nanoparticle supported imidazolium ionic liquid [SNImIL] was synthesized and utilized as a biocompatible additive for studying the thermal reversibility of human carbonic anhydrase II (HCA II). For this purpose, we prepared additive by modification of nanoparticles through the grafting of ionic liquids on the surface of nanoparticles (SNImIL). The SNImIL were fully characterized by Fourier Transform Infrared spectroscopy, scanning electron microscopy and thermo gravimetric analysis. The characterization of HCA II was investigated by various techniques including UVVis and ANS fluorescence spectrophotometry, differential scanning calorimetry, and docking study. SNImIL induced disaggregation, enhanced protein stability and increased thermal reversibility of HCA II by up to 42% at pH 7.75. PMID:22829053

  5. Effects of silica nanoparticle supported ionic liquid as additive on thermal reversibility of human carbonic anhydrase II.

    PubMed

    Fallah-Bagheri, Azadeh; Saboury, Ali Akbar; Ma'mani, Leila; Taghizadeh, Mohammad; Khodarahmi, Reza; Ranjbar, Samira; Bohlooli, Mousa; Shafiee, Abbas; Foroumadi, Alireza; Sheibani, Nader; Moosavi-Movahedi, Ali Akbar

    2012-12-01

    Silica nanoparticle supported imidazolium ionic liquid [SNImIL] was synthesized and utilized as a biocompatible additive for studying the thermal reversibility of human carbonic anhydrase II (HCA II). For this purpose, we prepared additive by modification of nanoparticles through the grafting of ionic liquids on the surface of nanoparticles (SNImIL). The SNImIL were fully characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and thermo gravimetric analysis. The characterization of HCA II was investigated by various techniques including UV-vis and ANS fluorescence spectrophotometry, differential scanning calorimetry, and docking study. SNImIL induced disaggregation, enhanced protein stability and increased thermal reversibility of HCA II by up to 42% at pH 7.75. PMID:22829053

  6. Buildings R&D Breakthroughs. Technologies and Products Supported by the Building Technologies Program

    SciTech Connect

    none,

    2012-04-01

    This report identifies and characterizes commercially available products and emerging (near-commercial) technologies that benefited from the support of the Building Technologies Program (BTP) within the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy. The investigation specifically focused on technology-oriented research and development (R&D) projects sponsored by BTP’s Emerging Technologies subprogram from 2005-2009.

  7. Buildings R&D Breakthroughs: Technologies and Products Supported by the Building Technologies Program

    SciTech Connect

    Weakley, Steven A.

    2012-04-15

    The purpose of the project described in this report is to identify and characterize commercially available products and emerging (near-commercial) technologies that benefited from the support of the Building Technologies Program (BTP) within the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy. The investigation specifically focused on technology-oriented research and development (R&D) projects funded by BTP’s Emerging Technologies subprogram from 2005-2011.

  8. Hollow fiber-supported designer ionic liquid sponges for post-combustion CO2 scrubbing

    SciTech Connect

    Lee, JS; Hillesheim, PC; Huang, DK; Lively, RP; Oh, KH; Dai, S; Koros, WJ

    2012-11-30

    A proof of concept study for a new type of carbon capture system is considered for post-combustion CO2 capture based on porous hollow fiber sorbents with ionic liquids sorbed in the cell walls of the fiber. This study proves that delicate morphological features in the open-celled porous wall can be maintained during the infusion process. Mixtures of task specific ionic liquid (i.e. [BMIM][Tf2N]) and superbase (i.e. DBU) were loaded into polyamide-imide (PAI) fibers by a so-called two-step non-solvent infusion protocol. In the protocol, methanol carries ionic liquids into the pore cell walls of hollow fibers and then hexane carries superbase to create an efficient CO2 sorbent. Our ionic liquid/superbase impregnation technique overcomes a serious increase in mass transfer resistance upon reaction with CO2, thereby allowing its large scale utilization for post-combustion CO2 capture. The investigation on the effect of different pore former additives (different molecular weights of polyvinylpyrrolidone, lithium nitrate, and their mixtures) suggested that a large molecular weight of PVP (M-w; 1300k) including dope composition produces highly interconnected open cell pore structures of PAI hollow fibers. Lastly, a lumen side barrier layer was successfully formed on the bore side of neat PAI fibers by using a mixture of Neoprene (R) with crosslinking agents (TSR-633) via a post-treatment process. The lumen layer will enable heat removal from the fiber sorbents during their application in rapid thermal swing cycling processes. (C) 2012 Elsevier Ltd. All rights reserved.

  9. Liquid perfluorochemical-supported hybrid cell culture system for proliferation of chondrocytes on fibrous polylactide scaffolds.

    PubMed

    Pilarek, Maciej; Grabowska, Iwona; Senderek, Ilona; Wojasi?ski, Micha?; Janicka, Justyna; Janczyk-Ilach, Katarzyna; Ciach, Tomasz

    2014-09-01

    CP5 bovine chondrocytes were cultured on biodegradable electrospun fibrous polylactide (PLA) scaffolds placed on a flexible interface formed between two immiscible liquid phases: (1) hydrophobic perfluorochemical (PFC) and (2) aqueous culture medium, as a new way of cartilage implant development. Robust and intensive growth of CP5 cells was achieved in our hybrid liquid-solid-liquid culture system consisting of the fibrous PLA scaffolds in contrast to limited growth of the CP5 cells in traditional culture system with PLA scaffold placed on solid surface. The multicellular aggregates of CP5 cells covered the surface of PLA scaffolds and the chondrocytes migrated through and overgrew internal fibers of the scaffolds. Our hybrid culture system simultaneously allows the adhesion of adherent CP5 cells to fibers of PLA scaffolds as well as, due to use of phase of PFC, enhances the mass transfer in the case of supplying/removing of respiratory gases, i.e., O2 and CO2. Our flexible (independent of vessel shape) system is simple, ready-to-use and may utilize a variety of polymer-based scaffolds traditionally proposed for implant development. PMID:24532258

  10. Highly selective separation of carbon dioxide from nitrogen and methane by nitrile/glycol-difunctionalized ionic liquids in supported ionic liquid membranes (SILMs).

    PubMed

    Hojniak, Sandra D; Silverwood, Ian P; Khan, Asim Laeeq; Vankelecom, Ivo F J; Dehaen, Wim; Kazarian, Sergei G; Binnemans, Koen

    2014-07-01

    Novel difunctionalized ionic liquids (ILs) containing a triethylene glycol monomethyl ether chain and a nitrile group on a pyrrolidinium or imidazolium cation have been synthesized and incorporated into supported ionic liquid membranes (SILMs). These ILs exhibit ca. 2.3 times higher CO2/N2 and CO2/CH4 gas separation selectivities than analogous ILs functionalized only with a glycol chain. Although the glycol moiety ensures room temperature liquidity of the pyrrolidinium and imidazolium ILs, the two classes of ILs benefit from the presence of a nitrile group in different ways. The difunctionalized pyrrolidinium ILs exhibit an increase in CO2 permeance, whereas the permeances of the contaminant gases rise negligibly, resulting in high gas separation selectivities. In the imidazolium ILs, the presence of a nitrile group does not always increase the CO2 permeance nor does it increase the CO2 solubility, as showed in situ by the ATR-FTIR spectroscopic method. High selectivity of these ILs is caused by the considerably reduced permeances of N2 and CH4, most likely due to the ability of the -CN group to reject the nonpolar contaminant gases. Apart from the CO2 solubility, IL-CO2 interactions and IL swelling were studied with the in situ ATR-FTIR spectroscopy. Different strengths of the IL-CO2 interactions were found to be the major difference between the two classes of ILs. The difunctionalized ILs interacted stronger with CO2 than the glycol-functionalized ILs, as manifested in the smaller bandwidths of the bending mode band of CO2 for the latter. PMID:24895912

  11. Influence of membrane solvent on strontium transport from reprocessing concentrate solutions through flat-sheet-supported liquid membranes

    SciTech Connect

    Dozol, J.F.; Casas, J. ); Sastre, A.M. )

    1993-08-01

    The influence of membrane solvents on strontium transport from nuclear fuel reprocessing concentrate solutions to demineralized water through a flat-sheet-supported liquid membrane has been studied using dicyclohexano-18-crown-6 as the extractant and Celgard 2500 as the solid support. Even though the highest values of the distribution coefficients of strontium were obtained with nitrated compounds as membrane solvents, strontium permeabilities were determined only when a membrane solvent was used for which stable SLMs were obtained. Among the latter, the use of 4-nonylphenol as a phase modifier is not satisfactory for long-term strontium transport experiments due to its reactivity with the nitric acid of the aqueous feed solution. We achieved a good correlation between strontium permeability and two parameters of the membrane diffusion coefficient (molecular weight and viscosity of the membrane solvent) for aromatic solvents modified with isotridecanol or 1-decanol. The best results were obtained with n-hexylbenzene (0.7 mol[center dot]L [sup 1]isotridecanol) which should lead to a high strontium decontamination by hollow-fiber-supported liquid membranes. The transport of nitric acid and nonradioactive cations through the membrane was not greatly influenced by the membrane solvent used. 10 refs., 4 figs., 7 tabs.

  12. Determination of ketamine, norketamine and dehydronorketamine in urine by hollow-fiber liquid-phase microextraction using an essential oil as supported liquid membrane.

    PubMed

    Bairros, Andr Valle de; Lanaro, Rafael; Almeida, Rafael Menck de; Yonamine, Mauricio

    2014-10-01

    Here, we present a method for the determination of ketamine (KT) and its main metabolites, norketamine (NK) and dehydronorketamine (DHNK) in urine samples by using hollow-fiber liquid-phase microextraction (HF-LPME) in the three-phase mode. The fiber pores were filled with eucalyptus essential oil and a solution of 1.0mol/L of HCl was introduced into the lumen of the fiber (acceptor phase). The fiber was submersed in the alkalinized urine containing 10% NaCl, and the system was submitted to lateral shaking (2400rpm) during 30min. Acceptor phase was withdrawn from the fiber, dried and the residue was then derivatized with trifluoroacetic anhydride (TFAA) for further determination by gas chromatography-mass spectrometry (GC-MS). The calibration curves were linear over the specified range and limits of detection (LoDs) obtained for KT, NK and DHNK were below the cut-off value (1.0ng/mL) recommended by the United Nations Office on Drugs and Crime (UNODC). A totally "green chemistry" approach of the sample extraction was obtained by using essential oil as a supported liquid membrane in HF-LPME. The developed method was successfully validated and applied to urine samples collected from two clinical cases in which KT was suspected to be involved. PMID:24810678

  13. Determination of chemotherapeutic drugs in human urine by capillary electrophoresis with UV and fluorimetric detection using solid-supported liquid-liquid extraction for sample clean-up.

    PubMed

    Hurtado-Sánchez, María del Carmen; Acedo-Valenzuela, María Isabel; Durán-Merás, Isabel; Rodríguez-Cáceres, María Isabel

    2015-06-01

    Capillary electrophoresis was used for the rapid determination of three chemotherapeutic drugs employed to treat colorectal cancer: irinotecan, tegafur, and leucovorin, and their main metabolites (7-ethyl-10-hydroxycamptothecin and 5-fluorouracil), in human urine samples. A phosphate buffer (pH 11.34; 20 mM) was selected as the background electrolyte. A hydrodynamic injection (9 s, 30 mbar) was applied and the separation was carried out using a separation temperature and voltage of 25°C and 25 kV, respectively. A capillary with two detection windows for serial online UV and fluorescence detection was satisfactorily employed. A solid-supported liquid-liquid extraction procedure was optimized for the clean-up of the urine samples and the extraction of the analytes. Matrix effects were assessed and signal suppression was observed for three of the analytes, thus, matrix-matched calibration was used for compensating residual matrix effects on these analytes. The proposed method allows the separation and quantification of the chemotherapeutics in less than 6 min. Detection limits range between 0.01 and 0.30 mg/L. The method was satisfactorily applied to the determination of the target compounds in human urine samples, with recoveries of 92.4-107.7%. PMID:25820908

  14. Simultaneous determination of polycyclic musks in blood and urine by solid supported liquid-liquid extraction and gas chromatography-tandem mass spectrometry.

    PubMed

    Liu, Hongtao; Huang, Liping; Chen, Yuxin; Guo, Liman; Li, Limin; Zhou, Haiyun; Luan, Tiangang

    2015-06-15

    A rapid, precise and accurate method for the simultaneous determination of 5 polycyclic musks (PCMs) in biological fluids was developed by solid supported liquid-liquid extraction (SLE) coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS). All parameters influencing SLE-GC-MS performance, including electron energy of electron-impact ionization source, collision energy for tandem mass spectrometer when operated in selected-reaction monitoring (SRM) mode, type and volume of elution reagent, nitrogen evaporation time, pH and salinity of sample have been carefully optimized. Eight milliliter of n-hexane was finally chosen as elution reagent. Blood and urine sample could be loaded into SLE cartridge without adjusting pH and salinity. Deuterated tonalide (AHTN-d3) was chosen as internal standard. The correlation coefficient (r(2)) of the calibration curves of target compounds ranged from 0.9996 to 0.9998. The dynamic range spanned over two orders of magnitude. The limit of detection (LOD) of target compounds in blood and urine ranged from 0.008 to 0.105μgL(-1) and 0.005 to 0.075μgL(-1), respectively. The developed procedure was successfully applied to the analysis of PCMs in human blood and urine obtaining satisfying recoveries on low, medium and high levels. The method was compared with SLE-GC-MS and shown one to two orders of magnitude improvement in sensitivity. PMID:25965876

  15. 3kW liquid-cooled elastically-supported Nd:YAG multi-slab CW laser resonator.

    PubMed

    Fu, Xing; Li, Peilin; Liu, Qiang; Gong, Mali

    2014-07-28

    A 3kW liquid-convection-cooled Nd:YAG CW laser resonator with a novel design is developed and demonstrated, in which the straight-through geometry is adopted that the oscillating laser propagates through multiple thin slabs and multiple cooling flow layers in Brewster angle. Using the elastically-supported Nd:YAG single-crystal thin slabs at different doping levels, a multimode laser output with the output power of 3006 W is obtained from the stable cavity at the pump power of 19960 W, corresponding to an optical-optical efficiency of 15.1%, and a slope efficiency of 21.2%. PMID:25089461

  16. Thermo-mechanical simulation of liquid-supported stretch blow molding

    SciTech Connect

    Zimmer, J.; Stommel, M.

    2015-05-22

    Stretch blow molding is the well-established plastics forming method to produce Polyehtylene therephtalate (PET) bottles. An injection molded preform is heated up above the PET glass transition temperature (Tg∼85°C) and subsequently inflated by pressurized air into a closed cavity. In the follow-up filling process, the resulting bottle is filled with the final product. A recently developed modification of the process combines the blowing and filling stages by directly using the final liquid product to inflate the preform. In a previously published paper, a mechanical simulation and successful evaluation of this liquid-driven stretch blow molding process was presented. In this way, a realistic process parameter dependent simulation of the preform deformation throughout the forming process was enabled, whereas the preform temperature evolution during forming was neglected. However, the formability of the preform is highly reduced when the temperature sinks below Tg during forming. Experimental investigations show temperature-induced failure cases due to the fast heat transfer between hot preform and cold liquid. Therefore, in this paper, a process dependent simulation of the temperature evolution during processing to avoid preform failure is presented. For this purpose, the previously developed mechanical model is used to extract the time dependent thickness evolution. This information serves as input for the heat transfer simulation. The required material parameters are calibrated from preform cooling experiments recorded with an infrared-camera. Furthermore, the high deformation ratios during processing lead to strain induced crystallization. This exothermal reaction is included into the simulation by extracting data from preform measurements at different stages of deformation via Differential Scanning Calorimetry (DSC). Finally, the thermal simulation model is evaluated by free forming experiments, recorded by a high-speed infrared camera.

  17. Thermo-mechanical simulation of liquid-supported stretch blow molding

    NASA Astrophysics Data System (ADS)

    Zimmer, J.; Stommel, M.

    2015-05-01

    Stretch blow molding is the well-established plastics forming method to produce Polyehtylene therephtalate (PET) bottles. An injection molded preform is heated up above the PET glass transition temperature (Tg˜85°C) and subsequently inflated by pressurized air into a closed cavity. In the follow-up filling process, the resulting bottle is filled with the final product. A recently developed modification of the process combines the blowing and filling stages by directly using the final liquid product to inflate the preform. In a previously published paper, a mechanical simulation and successful evaluation of this liquid-driven stretch blow molding process was presented. In this way, a realistic process parameter dependent simulation of the preform deformation throughout the forming process was enabled, whereas the preform temperature evolution during forming was neglected. However, the formability of the preform is highly reduced when the temperature sinks below Tg during forming. Experimental investigations show temperature-induced failure cases due to the fast heat transfer between hot preform and cold liquid. Therefore, in this paper, a process dependent simulation of the temperature evolution during processing to avoid preform failure is presented. For this purpose, the previously developed mechanical model is used to extract the time dependent thickness evolution. This information serves as input for the heat transfer simulation. The required material parameters are calibrated from preform cooling experiments recorded with an infrared-camera. Furthermore, the high deformation ratios during processing lead to strain induced crystallization. This exothermal reaction is included into the simulation by extracting data from preform measurements at different stages of deformation via Differential Scanning Calorimetry (DSC). Finally, the thermal simulation model is evaluated by free forming experiments, recorded by a high-speed infrared camera.

  18. Arctic Observations Supporting Liquid-Dependent Ice Nucleation at Low-Altitudes and Moderate Temperatures

    NASA Astrophysics Data System (ADS)

    de Boer, G.; Morrison, H.; Shupe, M.; Hildner, R.

    2010-12-01

    The nucleation of ice crystals in mixed-phase stratiform clouds can play a large role in controlling cloud lifetime, and therefore cloud radiative impact. Several recent field campaigns (e.g. M-PACE, ISDAC) were completed in part to better understand how ice forms in these cloud structures. Additionally, continuous measurements at ground-based observation sites in Barrow, AK, Eureka, Canada and over the Beaufort Sea during SHEBA provide us with an interesting perspective on the patterns and frequency of ice formation in the lower four kilometers of the atmosphere. Using a combination of lidar, radar, microwave radiometer and radiosonde measurements, multiple cases are observed revealing an initial resistance to ice formation despite cold (<-15 C) and ice-supersaturated conditions. In these cases, ice is eventually observed, but only immediately following formation of a liquid cloud layer. A statistical analysis of data collected at all three locations reveals that mixed-phase clouds are observed much more readily than ice-only clouds between -5 and -30 C. Additionally, very few ice-only clouds were observed within this temperature range at relative humidities between ice and liquid saturation. We will present these results in more detail, and provide discussion points on location-dependent differences and implications on the simulation of ice nucleation over a wide variety of model scales.

  19. Triplet state properties of the OLED emitter Ir(btp)2(acac): characterization by site-selective spectroscopy and application of high magnetic fields.

    PubMed

    Finkenzeller, Walter J; Hofbeck, Thomas; Thompson, Mark E; Yersin, Hartmut

    2007-06-11

    The well-known red emitting complex Ir(btp)2(acac) (bis(2-(2'-benzothienyl)-pyridinato-N,C3')iridium(acetylacetonate)), frequently used as emitter material in OLEDs, has been investigated in a polycrystalline CH2Cl2 matrix. The studies were carried out under variation of temperature down to 1.2 K and at magnetic fields up to B=10 T. Highly resolved emission and excitation spectra of several specific sites are obtained by site-selective spectroscopy. For the preferentially investigated site (I-->0 at 16268 cm-1), the three substates I, II, and III of the T1 triplet state are separated by DeltaEII-I=2.9 cm-1 and DeltaEIII-I=25.0 cm-1, respectively. DeltaEIII-I represents the total zero-field splitting (ZFS). The individual decay times of these substates are tauI=150 micros, tauII=58 micros, and tauIII=2 micros, respectively. The long decay time of the lowest substate I indicates its almost pure triplet character. The time for relaxation from state II to state I (spin-lattice relaxation, SLR) is as long as 22 micros at T=1.5 K, while the thermalization between the two lower lying substates and substate III is fast. Application of a magnetic field induces Zeeman mixing of the substates of T1, resulting in an increased splitting between the two lower lying substates from 2.9 cm-1 at zero field to, for example, 6.8 cm-1 at B=10 T. Further, the decay time of the B-field perturbed lowest substate IB decreases by a factor of about 7 up to 10 T. The magnetic field properties clearly show that the three investigated states belong to the same triplet parent term of one single site. Other sites show a similar behavior, though the values of ZFS vary between 15 and 27 cm-1. Since the amount of ZFS reflects the extent of MLCT (metal-to-ligand charge transfer) parentage, it can be concluded that the emitting state T1 is a 3LC (ligand centered) state with significant admixtures of 1,3MLCT (metal-to-ligand charge transfer) character. Interestingly, the results show that the MLCT perturbation is different for the various sites. An empirical correlation between the amount of ZFS and the compound's potential for its use as emitter material in an OLED is presented. As a rule of thumb, a triplet emitter is considered promising for application in OLEDs, if it has a ZFS larger than about 10 cm-1. PMID:17488070

  20. Electrochemical gas sensors based on paper-supported room-temperature ionic liquids for improved analysis of acid vapours.

    PubMed

    Toniolo, Rosanna; Dossi, Nicolò; Pizzariello, Andrea; Casagrande, Alice; Bontempelli, Gino

    2013-04-01

    A prototype of a fast-response task-specific amperometric gas sensor based on paper-supported room-temperature ionic liquids (RTILs) is proposed here for improved analysis of volatile acid species. It consists of a small filter paper foil soaked with a RTIL mixture containing an ionic liquid whose anion (acetate) displays a basic character, upon which three electrodes are screen printed by carbon ink profiting from a suitable mask. It takes advantage of the high electrical conductivity and negligible vapour pressure of RTILs and of their easy immobilization into a porous and inexpensive supporting material such as paper. The performance of this device, used as a wall-jet amperometric detector for flow injection analyses of headspace samples in equilibrium with aqueous solutions at controlled concentrations, was evaluated for phenol and 1-butanethiol vapours which were adopted as model acid gaseous analytes. The results obtained showed that the quite high potentials required for the detection of these analytes are lowered significantly, thanks to the addition of the basic acetate RTIL. In such a way, overlap with the medium discharge is avoided, and the possible adverse effect of interfering species is minimised. The sensor performance was quite satisfactory (detection limits, ca. 0.3 μM; dynamic range, ca. 1-200 μM, both referred to solution concentrations; correlation coefficients in the range 0.993-0.997; repeatability, ± 6% RSD; long-term stability, 9%); thus suggesting the possible use of this device for manifold applications. PMID:23232956

  1. Apparatus for supporting contactors used in extracting nuclear materials from liquids

    DOEpatents

    Leonard, Ralph A. (River Forest, IL); Frank, Robert C. (Crestwood, IL)

    1991-01-01

    Apparatus is provided for supporting one or more contactor stages used to remove radioactive materials from aqueous solutions. The contactor stages include a housing having an internal rotor, a motor secured to the top of the housing for rotating the rotor, and a drain in the bottom of the housing. The support apparatus includes two or more vertical members each secured to a ground support that is horizontal and perpendicular to the frame member, and a horizontally disposed frame member. The frame member may be any suitable shape, but is preferably a rectangular tube having substantially flat, spaced top and bottom surfaces separated by substantially vertical side surfaces. The top and bottom surfaces each have an opening through which the contactor housing is secured so that the motor is above the frame and the drain is below the frame during use.

  2. Hydrophobic effects on supported ionic liquid phase Pd nanoparticle hydrogenation catalysts.

    PubMed

    Luza, Leandro; Gual, Aitor; Rambor, Camila P; Eberhardt, Dario; Teixeira, Srgio R; Bernardi, Fabiano; Baptista, Daniel L; Dupont, Jairton

    2014-09-14

    Hybrid organosilicas prepared by sol-gel processes using 1-n-butyl-3-(3-trimethoxysilylpropyl)-imidazolium cations associated with hydrophilic and hydrophobic anions can be easily decorated with well dispersed and similar size (1.8-2.1 nm) Pd nanoparticles (Pd-NPs) by simple sputtering-deposition. Higher Pd concentration at the surface compared to the deeper region is obtained in the supports with smaller pore diameter (containing hydrophobic ILs) than in supports with the largest pore diameter (containing hydrophilic ILs). The IL hydrophobicity plays a central role in the hydrogenation of dienes by controlling the diene access to NP surface active sites. PMID:25057970

  3. Diffusion coefficient of an inclusion in a liquid membrane supported by a solvent of arbitrary thickness

    NASA Astrophysics Data System (ADS)

    Seki, Kazuhiko; Ramachandran, Sanoop; Komura, Shigeyuki

    2011-08-01

    The diffusion coefficient of an inclusion in a liquid membrane is investigated by taking into account the interaction between membranes and bulk solvents of arbitrary thickness. As illustrative examples, the diffusion coefficients of two types of inclusions, a circular domain composed of fluid with the same viscosity as the host membrane and that of a polymer chain embedded in the membrane, are studied. The diffusion coefficients are expressed in terms of the hydrodynamic screening lengths, which vary according to the solvent thickness. When the membrane fluid is dragged by the solvent of finite thickness, via stick boundary conditions, multiple hydrodynamic screening lengths together with the weight factors to the diffusion coefficients are obtained from the characteristic equation. The conditions for which the diffusion coefficients can be approximated by the expression including only a single hydrodynamic screening length are also shown.

  4. Influence of support on the performance of molybdenum sulfide catalysts used to hydrotreat coal liquids

    SciTech Connect

    McCormick, R.L.

    1988-01-01

    Supports for molybdenum sulfide hydrotreating catalysts included silica, silica-magnesia, titania, chromia-alumina, activated carbon and nitrided activated carbon. The alumina supported Amocat 1A and Amocat 1C as well as the silica-alumina supported, Harshaw CoMo-0402 were also studied. Catalysts were characterized by BET surface area, mercury porosimetry and x-ray powder diffraction. Acidity was measured by the temperature programmed desorption of tert-butyl amine. Initial activity screening studies were conducted in a stirred autoclave batch reactor to determine appropriate metals loadings for the various supports. Initially active catalysts were then tested in a bench scale, trickle bed reactor to determine activity maintenance, coking tendency and selectivity at lined out conditions. Selectivities for hydrodenitrogenation and for the production of hydrogen donor molecules were of interest. The donatable hydrogen content of the produce was determined by {sup 1}H and {sup 13}C NMR spectroscopy. The results indicated a strong correlation between lined out hydrogenation activity and the volume in 60-200 {angstrom} diameter pores. A second correlation was observed between HDN activity and acid site density, indicating the importance of acid sites in denitrogenation. Low acidity catalysts appeared to produce a greater hydrogen donor content in the product oil than did high acidity catalysts but the results were not conclusive. The results also suggest that Bronsted acid sites can markedly reduce coking tendency but that in general, coke formation is related in a complex way to the acid/base chemistry of the surface.

  5. The Influence of MSI (Metal-Support Interactions) and the Solvent in Liquid-Phase Reactions

    SciTech Connect

    Vannice, M. A.

    2003-05-30

    Results were repeatedly obtained that were consistent with a hypothesis proposed at the beginning of this program, i.e., due to Metal-Support Interactions (MSI), unique active sites can be created in the metal-support interfacial region to enhance activity and improve selectivity in certain types of reactions, especially those involving the hydrogenation of carbonyl and unsaturated C=C bonds. Higher turnover frequencies (TOF-molecule/s/site) and increased selectivity for C=O bond versus C=C bond hydrogenation was established in the hydrogenation reactions of: acetone, crotonaldehyde, acetophenone, phenylethanol, acetylcyclohexane, benzaldehyde, benzyl alcohol, phenylacetaldehyde and citral over Pt/TiO{sub 2} MSI catalysts. Higher rates of hydrogenation benzene, toluene and xylene could be obtained over certain supported Pt and Pd catalysts. Au/TiO{sub 2} catalysts were developed that were active for CO hydrogenation at subambient temperatures. The influence of support and metal crystallite size were established for the adsorption of H{sub 2}, CO and O{sub 2} on families of Pt and Pd catalysts.

  6. Designing Supported Ionic Liquids (ILs) within Inorganic Nanosheets for CO2 Capture Applications.

    PubMed

    Zhou, Yingjie; Liu, Jingjing; Xiao, Min; Meng, Yuezhong; Sun, Luyi

    2016-03-01

    A new methodology was developed for the immobilization of ionic liquids (ILs) on α-zirconium phosphate (ZrP) and montmorillonite (MMT) single-layer nanosheets via a facile coassembly process. The coassembled inorganic nanosheet/1-n-butyl-3-methylimidazolium chloride (BMIMCl) hybrids were systematically characterized. The results showed that the ILs were successfully assembled with ZrP or MMT single-layer nanosheets to form an intercalated structure. The inorganic nanosheet/IL hybrids can serve as efficient CO2 absorbents. The CO2 sorption of BMIMCl could be made up to 21 times more efficient because of the high exposure of the functional groups of BMIMCl in the coassembled hybrids. CO2 was physically absorbed by the hybrids with a slow equilibrium time at lower temperatures, whereas higher temperatures allowed for faster diffusion and chemical absorption of CO2. The best CO2 capture capacities of the hybrids were 0.73 mmol/g at 60 °C for ZrP/BMIMCl and 0.42 mmol/g at 70 °C for MMT/BMIMCl. PMID:26840623

  7. Liquid phase methanol LaPorte process development unit: Modification, operation, and support studies

    SciTech Connect

    Not Available

    1990-10-23

    The objectives of this program are to implement and test the process improvements identified through the engineering studies of the current program to demonstrate the capability of long-term catalyst activity maintenance, and to perform process and design engineering work that can be applied to a scaled-up Liquid Phase Methanol (LPMEOH) facility. An optional series of PDU runs is offered to extend the testing of the process improvements. A parallel research program will be performed to enhance the LPMEOH technical data base to improve the likelihood of commercialization of the LPMEOH process. Activities this quarter include: Flow sheet development for La Porte PDU modifications continues. A preliminary P ID review was completed and flow sheet modifications were identified and are being incorporated. A preliminary hazards review was completed on 22 May. Some minor flow sheet modifications resulted and a number of action items were identified. The most significant action item is to develop a materials reactivity and compatibility grid for the different alcohols, ethers, and esters which will be produced at the PDU. Heat and material balances were completed for the maximum production case of the mixed DME/MEOH synthesis campaign. An improved rate expression was developed. 1 fig.

  8. Ionic liquid-based preparation of cellulose-dendrimer films as solid supports for enzyme immobilization.

    PubMed

    Bagheri, Mozhgan; Rodríguez, Héctor; Swatloski, Richard P; Spear, Scott K; Daly, Daniel T; Rogers, Robin D

    2008-01-01

    Surface-active cellulose films for covalent attachment of bioactive moieties were achieved by codissolution of cellulose with polyamidoamine (PAMAM) dendrimers in an ionic liquid followed by regeneration of the composite as a film. Different generations of PAMAM were used for the formation of cellulose-dendrimer composites, as well as films with the dendrimer covalently bonded to the cellulose by means of the linker 1,3-phenylene diisocyanate. Surface characterization, thermal stability, and utility for immobilization of laccase were determined. The presence of the dendrimer amino groups was confirmed by detailed characterization of the films' surfaces. These modified films exhibit acceptable thermal stability, comparable to that of other regenerated cellulose films, but the number of active functional groups on the surface is much smaller than the theoretical amount expected. Films made with 1,3-phenylene diisocyanate as linker for covalently bound cellulose and dendrimers exhibit a better performance for immobilization of laccase than those prepared by simple mixing of the cellulose and dendrimer. In general, a linear correspondence between the dendrimer generation within the films and the specific activity of immobilized laccase in such films was not observed. PMID:18163541

  9. Liquid phase methanol LaPorte process development unit: Modification operation, and support studies

    SciTech Connect

    Not Available

    1991-01-28

    In April 1987, Air Products started the third and final contract with the US Department of Energy to develop the Liquid Phase Methanol (LPMEOH) process. One of the objectives was to identify alternative commercial catalyst(s) for the process. This objective was strategically important as we want to demonstrate that the LPMEOH process is flexible and not catalyst selection limited. Among three commercially available catalysts evaluated in the lab, the catalyst with a designation of F21/0E75-43 was the most promising candidate. The initial judging criteria included not only the intrinsic catalyst activity but also the ability to be used effectively in a slurry reactor. The catalyst was then advanced for a 40-day life test in a laboratory 300 cc autoclave. The life test result also revealed superior stability when compared with that of a standard catalyst. Consequently, the new catalyst was recommended for demonstration in the Process Development Unit (PDU) at LaPorte, Texas. This report details the methodology of testing and selecting the catalyst.

  10. Liquid Phase Methanol LaPorte Process Development Unit: Modification, operation, and support studies

    SciTech Connect

    Not Available

    1990-08-31

    A gas phase and a slurry phase radioactive tracer study was performed on the 12 ton/day Liquid Phase Methanol (LPMEOH) Process Development Unit (PDU) in LaPorte, Texas. To study the gas phase mixing characteristics, a radioactive argon tracer was injected into the feed gas and residence time distribution was generated by measuring the response at the reactor outlet. Radioactive manganese oxide powder was independently injected into the reactor to measure the slurry phase mixing characteristics. A tanks-in-series model and an axial dispersion model were applied to the data to characterize the mixing in the reactor. From the axial dispersion model, a translation to the number of CSTR's (continuous stirred tank reactors) was made for comparison purposes with the first analysis. Dispersion correlations currently available in the literature were also compared. The tanks-in-series analysis is a simpler model whose results are easily interpreted. However, it does have a few drawbacks; among them, the lack of a reliable method for scaleup of a reactor and no direct correlation between mixing in the slurry and gas phases. The dispersion model allows the mixing in the gas and slurry phases to be characterized separately while including the effects of phase transfer. This analysis offers a means for combining the gas and slurry phase dispersion models into an effective dispersion coefficient, which, in turn, can be related to an equivalent number of tanks-in-series. The dispersion methods reported are recommended for scaleup of a reactor system. 24 refs., 18 figs., 8 tabs.

  11. Unlocking the potential of supported liquid phase catalysts with supercritical fluids: low temperature continuous flow catalysis with integrated product separation

    PubMed Central

    Franciò, Giancarlo; Hintermair, Ulrich; Leitner, Walter

    2015-01-01

    Solution-phase catalysis using molecular transition metal complexes is an extremely powerful tool for chemical synthesis and a key technology for sustainable manufacturing. However, as the reaction complexity and thermal sensitivity of the catalytic system increase, engineering challenges associated with product separation and catalyst recovery can override the value of the product. This persistent downstream issue often renders industrial exploitation of homogeneous catalysis uneconomical despite impressive batch performance of the catalyst. In this regard, continuous-flow systems that allow steady-state homogeneous turnover in a stationary liquid phase while at the same time effecting integrated product separation at mild process temperatures represent a particularly attractive scenario. While continuous-flow processing is a standard procedure for large volume manufacturing, capitalizing on its potential in the realm of the molecular complexity of organic synthesis is still an emerging area that requires innovative solutions. Here we highlight some recent developments which have succeeded in realizing such systems by the combination of near- and supercritical fluids with homogeneous catalysts in supported liquid phases. The cases discussed exemplify how all three levels of continuous-flow homogeneous catalysis (catalyst system, separation strategy, process scheme) must be matched to locate viable process conditions. PMID:26574523

  12. MAGNETIC LIQUID DEFORMABLE MIRRORS FOR ASTRONOMICAL APPLICATIONS: ACTIVE CORRECTION OF OPTICAL ABERRATIONS FROM LOWER-GRADE OPTICS AND SUPPORT SYSTEM

    SciTech Connect

    Borra, E. F.

    2012-08-01

    Deformable mirrors are increasingly used in astronomy. However, they still are limited in stroke for active correction of high-amplitude optical aberrations. Magnetic liquid deformable mirrors (MLDMs) are a new technology that has the advantages of high-amplitude deformations and low costs. In this paper, we demonstrate extremely high strokes and interactuator strokes achievable by MLDMs which can be used in astronomical instrumentation. In particular, we consider the use of such a mirror to suggest an interesting application for the next generation of large telescopes. We present a prototype 91 actuator deformable mirror made of a magnetic liquid (ferrofluid). This mirror uses a technique that linearizes the response of such mirrors by superimposing a large and uniform magnetic field on the magnetic field produced by an array of small coils. We discuss experimental results that illustrate the performance of MLDMs. A most interesting application of MLDMs comes from the fact they could be used to correct the aberrations of large and lower optical quality primary mirrors held by simple support systems. We estimate basic parameters of the needed MLDMs, obtaining reasonable values.

  13. Unlocking the potential of supported liquid phase catalysts with supercritical fluids: low temperature continuous flow catalysis with integrated product separation.

    PubMed

    Franciò, Giancarlo; Hintermair, Ulrich; Leitner, Walter

    2015-12-28

    Solution-phase catalysis using molecular transition metal complexes is an extremely powerful tool for chemical synthesis and a key technology for sustainable manufacturing. However, as the reaction complexity and thermal sensitivity of the catalytic system increase, engineering challenges associated with product separation and catalyst recovery can override the value of the product. This persistent downstream issue often renders industrial exploitation of homogeneous catalysis uneconomical despite impressive batch performance of the catalyst. In this regard, continuous-flow systems that allow steady-state homogeneous turnover in a stationary liquid phase while at the same time effecting integrated product separation at mild process temperatures represent a particularly attractive scenario. While continuous-flow processing is a standard procedure for large volume manufacturing, capitalizing on its potential in the realm of the molecular complexity of organic synthesis is still an emerging area that requires innovative solutions. Here we highlight some recent developments which have succeeded in realizing such systems by the combination of near- and supercritical fluids with homogeneous catalysts in supported liquid phases. The cases discussed exemplify how all three levels of continuous-flow homogeneous catalysis (catalyst system, separation strategy, process scheme) must be matched to locate viable process conditions. PMID:26574523

  14. A review of the supply of liquid propellants and other fluids in support of the Space Shuttle Program

    NASA Technical Reports Server (NTRS)

    Churchwell, Stacy E.; Bain, A. L.

    1989-01-01

    In this study, over twenty significant liquid propellants and other fluids were reviewed as to their supply in support of the Space Shuttle Program (SSP), primarily at KSC. The uniqueness of most of the products, either by their application or production characteristics, present a variety of supply issues to contend with. Each, however, is critical to the success of the SSP. It becomes necessary to formulate, and maintain, a logistic approach to assure a continued availability of each product. For convenience, two categories were established. One, labeled limited-availability, represents those products wherein they are single sourced, have production restrictions and/or there has been a history of supply problems. The other, labeled universally-available, is characteristic of those having several sources and/or having little, if any, historical supply problems. This last category was not examined in depth. Through concepts of establishing stockpile inventories, multiple supply contracts, or other arrangements, the supply of liquid propellants and other fluids can be assured.

  15. Extraction of lutetium(III) from aqueous solutions by employing a single fibre-supported liquid membrane.

    PubMed

    Trti?-Petrovi?, Tatjana M; Kumri?, Ksenija R; Dordevi?, Jelena S; Vladisavljevi?, Goran T

    2010-07-01

    Transport behaviour of Lu(III) across a polypropylene hollow fibre-supported liquid membrane containing di(2-ethylhexyl)phosphoric acid (DEHPA) in dihexyl ether as a carrier has been studied. The donor phase was LuCl(3) in the buffer solution consisting of 0.2 M sodium acetate at pH 2.5-5.0. A miniaturised system with a single hollow fibre has been operated in a batch mode. The concentration of Lu(III) was determined by indirect voltammetric method using Zn-EDTA complex. The effect of pH and volume of the donor phase, DEHPA concentration in the organic (liquid membrane) phase, the time of extraction and the content of the acceptor phase on the Lu(III) extraction and stripping behaviour was investigated. The results were discussed in terms of the pertraction and removal efficiency, the memory effect and the mean flux of Lu(III). The optimal conditions for the removal of (177)Lu(III) from labelled (177)Lu-radiopharmaceuticals were discussed and identified. The removal efficiency of Lu(III) greater than 99% was achieved at pH of the donor phase between 3.5 and 5.0 using DEHPA concentration in the organic phase of 0.47 M and the ratio of the donor to the acceptor phase of 182. PMID:20506430

  16. Use of supported liquid membranes incorporated in a flow system for the direct determination of eugenol in spice samples.

    PubMed

    Luque, M; Ros, A; Valcrcel, M

    2000-10-01

    A method for the determination of eugenol in spice samples based on the use of supported liquid membranes coupled to a flow system was developed. The solid sample is placed directly in the membrane unit without any treatment and the analyte is extracted from the sample, passes through the membrane and is conducted to the flow cell by the acceptor stream. This stream flows through the detector, allowing the measurement of the analyte by using a PVC-graphite composite electrode, versus Ag/AgCl/3 M KCl at +0.3 V, placed in a well-jet flow cell as amperometric detector. The method allowed the determination of eugenol in the range 0.5-30 micrograms ml-1 with a relative standard deviation of 5%. Results provided by the proposed procedure when applied to clove and seasoning samples agreed well with those obtained by a reference method. PMID:11070549

  17. Feasible way of Human Solid and Liquid Wastes' Inclusion Into Intersystem Mass Exchange of Biological-Technical Life Support Systems

    NASA Astrophysics Data System (ADS)

    Ushakova, Sofya; Tikhomirov, Alexander A.; Tikhomirova, Natalia; Kudenko, Yurii; Griboskaya, Illiada; Gros, Jean-Bernard; Lasseur, Christophe

    The basic objective arising at use of mineralized human solid and liquid wastes serving as the source of mineral elements for plants cultivation in biological-technical life support systems appears to be NaCl presence in them. The given work is aimed at feasibility study of mineralized human metabolites' utilization for nutrient solutions' preparation for their further employment at a long-term cultivation of uneven-aged wheat and Salicornia europaea L. cenosis in a conveyer regime. Human solid and liquid wastes were mineralized by the "wet incineration" method developed by Yu. Kudenko. On their base the solutions were prepared which were used for cultivation of 5-aged wheat conveyer with the time step-interval of 14 days. Wheat was cultivated by hydroponics method on expanded clay aggregate. For partial demineralization of nutrient solution every two weeks after regular wheat harvesting 12 L of solution was withdrawn from the wheat irrigation tank and used for Salicornia europaea cultivation by the water culture method in a conveyer regime. The Salicornia europaea conveyer was represented by 2 ages with the time step-interval of 14 days. Resulting from repeating withdrawal of the solution used for wheat cultivation, sodium concentration in the wheat irrigation solution did not exceed 400 mg/l, and mineral elements contained in the taken solution were used for Salicornia europaea cultivation. The experiment lasted 7 months. Total wheat biomass productivity averaged 30.1 g*m-2*day-1 at harvest index equal to 36.8The work was carried out under support of SB RAS grant 132 and INTAS 05-1000008-8010

  18. Permeation of iridium(IV) and metal impurity chlorocomplexes through a supported liquid membrane designed for rhodium separation

    SciTech Connect

    Ashrafizadeh, S.N.; Demopoulos, G.P.; Rovira, M.; Sastre, A.M.

    1998-06-01

    A supported liquid membrane (SLM) system previously designed for Rh separation has been examined for its capability to reject the metal impurities which are commonly encountered in industrial Rh chloride solutions. Special attention was paid to Ir(IV) chlorocomplexes and their extraction/transport behavior against both conventional solvent extraction and supported liquid membrane systems of Kelex 100. A lab-scale SLM cell with an effective membrane area of 44 cm{sup 2} was used to conduct the SLM permeation tests. The SLM was composed of a Gore-Tex polymer substrate impregnated with an organic solution of Kelex 100, tridecanol, and kerosene. The impurities tested [in addition to Ir(IV)] were AG(I), As(V), Bi(III), Cd(II), Co(II), Cu(II), Fe(III), Ni(II), Pb(II), Pd(II), Pt(IV), Se(IV), Te(IV), and Zn(II). These impurities, based on their response against the SLM, were classified into three groups, i.e., those permeated through [Zn(II), Pb(II), Cd(II), Bi(III), Te(IV), and Ir(IV)], those nonpermeated at all [Ni(II), Co(II), As(V), Se(IV), Cu(II), and Fe(III)], and those blocking the membrane [Pt(IV), Pd(II), Ag(I), Pb(II), and Bi(III)]. The SLM was not capable of discriminating between Rh(III) and Ir(IV) transport at the optimum operating conditions. Complementary upstream and downstream processes are required to separate the impurities from the feed and the product solutions, respectively. Overall, this work revealed the great limitations of SLMs as effective and potentially useful separation media for the extraction of metals from industrial-like multicomponent aqueous feed solutions.

  19. Simultaneous determination of total fatty acid esters of chloropropanols in edible oils by gas chromatography-mass spectrometry with solid-supported liquid-liquid extraction.

    PubMed

    Liu, Qing; Han, Feng; Xie, Ke; Miao, Hong; Wu, Yongning

    2013-11-01

    This study aimed to establish a novel robust method for the simultaneous determination of total fatty acid esters of 4 chloropropanols including fatty acid esters of 3-monochloropropane-1,2-diol (3-MCPD esters), 2-monochloropropane-1,3-diol (2-MCPD esters), 1,3-dichloropropan-2-ol (1,3-DCP esters) and 2,3-dichloropropan-1-ol (2,3-DCP esters) in edible oils. In this method, sodium methylate in methanol was used as the reagent for the ester cleavage reaction of chloropropanols esters. The reaction products were extracted by a sodium sulfate solution, and then purified by solid-supported liquid-liquid extraction (SLE) using diatomaceous earth (Hydromatrix™) as the sorbent. Finally, the extracts were derivatized with heptafluorobutyrylim idazole (HFBI) and analyzed by gas chromatography-mass spectrometry (GC-MS). Quantification was achieved using deuterated chloropropanols as their respective internal standards, including 3-MCPD-d5, 2-MCPD-d5, 1,3-DCP-d5 and 2,3-DCP-d5. A good linear relationship between peak area and concentrations was obtained within the range of 0.025-2.000mgL(-1) with a correlation coefficients not less than 0.999 for all the chloropropanols esters. The limits of detection (LODs) of esters of 3-MCPD, 2-MCPD, 1,3-DCP and 2,3-DCP (calculated as corresponding chloropropanols) were 30, 30, 100 and 30μgkg(-1), respectively. The average recoveries of the 3-MCPD esters and the 4 chloropropanols spiked at 0.1, 0.5 and 2mgkg(-1) into blank oil matrix were typically in a range from 70.7% to 113.3%. The robust method validation data including calibration, LOD/LOQ, accuracy and repeatability and proficiency test results (Z-score: -0.5) of the official Food Analysis Performance Assessment Scheme (FAPAS) indicated that the present quantitative method could be successfully applied to the determination of total chloropropanols esters in various edible oils. PMID:24070627

  20. Total Liquid Ventilation Provides Superior Respiratory Support to Conventional Mechanical Ventilation in a Large Animal Model of Severe Respiratory Failure

    PubMed Central

    Pohlmann, Joshua R; Brant, David O; Daul, Morgan A; Reoma, Junewai L; Kim, Anne C; Osterholzer, Kathryn R; Johnson, Kent J; Bartlett, Robert H; Cook, Keith E; Hirschl, Ronald B

    2011-01-01

    Total liquid ventilation (TLV) has the potential to provide respiratory support superior to conventional mechanical ventilation (CMV) in the acute respiratory distress syndrome (ARDS). However, laboratory studies are limited to trials in small animals for no longer than 4 hours. The objective of this study was to compare TLV and CMV in a large animal model of ARDS for 24 hours. Ten sheep weighing 53 4 (SD) kg were anesthetized and ventilated with 100% oxygen. Oleic acid was injected into the pulmonary circulation until PaO2:FiO2 ? 60 mmHg, followed by transition to a protective CMV protocol (n=5) or TLV (n=5) for 24 hours. Pathophysiology was recorded and the lungs were harvested for histological analysis. Animals treated with CMV became progressively hypoxic and hypercarbic despite maximum ventilatory support. Sheep treated with TLV maintained normal blood gases with statistically greater PO2 (p<10?9) and lower PCO2 (p < 10?3) than the CMV group. Survival at 24 hours in the TLV and CMV groups were 100% and 40% respectively (p< 0.05). Thus, TLV provided gas exchange superior to CMV in this laboratory model of severe ARDS. PMID:21084968

  1. Controlled synthesis and electrocatalytic characteristics of Pt nanoparticles-supported nanographene synthesized by in-liquid plasma

    NASA Astrophysics Data System (ADS)

    Kondo, Hiroki; Amano, Tomoki; Ishikawa, Kenji; Sekine, Makoto; Hori, Masaru; Hiramatsu, Mineo; Meijo University Collaboration; Nagoya University Team

    2014-10-01

    We investigated a high-speed synthesis of high-crystallinity nanographenes over 1 micro-gram/min using in-liquid plasma. In this study, nanographene materials with different crystallinity were synthesized using ethanol and 1-butanol. Pt nanoparticles were supported on their surfaces reducing 8 wt%-H2PtCl6 in H2O. G-band and D-band peaks in Raman spectra indicated nanographene materials. Nanographene materials synthesized using ethanol have higher crystallinity than those synthesized using 1-butanol. According to X-ray diffraction patterns, sizes of Pt nanoparticles are almost similar regardless of alcohol types. In cyclic voltammetry characteristics, peaks related to adsorption and desorption of hydrogen were clearly found in the both cases. The platinum effective areas were estimated to be 208.5 and 147.63 m2/g for the cases using ethanol and 1-butanol, respectively. In addition, after potential cycling tests, nanographene materials synthesized using ethanol show almost no degradation, while those using 1-butanol show a drastic degradation. These results indicate that the higher-density Pt nanoparticles can be supported on the higher-crystallinity nanographene material and they show higher durability.

  2. Cyanophenyl vs. pyridine substituent: impact on the adlayer structure and formation on HOPG and Au(111).

    PubMed

    Dai, Y; Eggers, B; Metzler, M; Knzel, D; Gro, A; Jacob, T; Ziener, U

    2016-03-01

    A new cyano substituted bis(terpyridine) derivative CN-BTP was synthesized and its adsorption on highly oriented pyrolytic graphite (HOPG) and Au(111) was investigated. CN-BTP is closely related to the previously investigated 2,4'-BTP, where the cyanophenyl groups are replaced by pyridine moieties. The scanning tunneling microscopy (STM) investigation of CN-BTP at the liquid|HOPG interface shows a highly ordered herringbone structure that is stabilized by double weak intermolecular C-HN hydrogen bonds, partially through the -CN substituents, which is different from the most stable square structure of 2,4'-BTP. The adsorption processes were investigated using cyclic voltammetry (CV) on Au(111) in a neutral phosphate buffer. A fast and full adlayer formation could be observed with CN-BTP, whereas an extremely slow process with 2,4'-BTP under the same conditions was found. Our data show that the CN substituents on BTP not only change the structure of the monolayer at the liquid|HOPG interface, but also accelerate the phase transition process in the electrolyte dramatically. This could be explained by the adlayer-substrate interactions, which is supported by DFT calculations. Our findings might be extended more generally to further pyridine comprising self-assembling molecules to fine-tune the adlayer structure and phase transition/adsorption kinetics by replacing pyridine by cyanophenyl moieties. PMID:26871757

  3. Novel analytical procedure using a combination of hollow fiber supported liquid membrane and dispersive liquid-liquid microextraction for the determination of aflatoxins in soybean juice by high performance liquid chromatography - Fluorescence detector.

    PubMed

    Simão, Vanessa; Merib, Josias; Dias, Adriana N; Carasek, Eduardo

    2016-04-01

    This study describes a combination between hollow fiber membrane and dispersive liquid-liquid microextraction for determination of aflatoxins in soybean juice by HPLC. The main advantage of this approach is the use of non-chlorinated solvent and small amounts of organic solvents. The optimum extraction conditions were 1-octanol as immobilized solvent; toluene and acetone at 1:5 ratio as extraction and disperser solvents (100 μL), NaCl at 2% of the sample volume and extraction time of 60 min. The optimal condition for the liquid desorption was 150 μL acetonitrile:water (50:50 v/v) and desorption time of 20 min. The linear range varied from 0.03 to 21 μg L(-1), with R(2) coefficients ranging from 0.9940 to 0.9995. The limits of detection and quantification ranged from 0.01 μg L(-1) to 0.03 μg L(-1) and from 0.03 μg L(-1) to 0.1 μg L(-1), respectively. Recovery tests ranged from 72% to 117% and accuracy between 12% and 18%. PMID:26593494

  4. Supported Ionic Liquid Membranes and Ion-Jelly Membranes with [BMIM][DCA]: Comparison of Its Performance for CO2 Separation.

    PubMed

    Couto, Ricardo; Neves, Lusa; Simes, Pedro; Coelhoso, Isabel

    2015-01-01

    In this work, a supported ionic liquid membrane (SILM) was prepared by impregnating a PVDF membrane with 1-butyl-3-methylimidazolium dicyanamide ([BMIM][DCA]) ionic liquid. This membrane was tested for its permeability to pure gases (CO2, N2 and O2) and ideal selectivities were calculated. The SILM performance was also compared to that of Ion-Jelly membranes, a new type of gelled membranes developed recently. It was found that the PVDF membrane presents permeabilities for pure gases similar or lower to those presented by the Ion-Jelly membranes, but with increased ideal selectivities. This membrane presents also the highest ideal selectivity (73) for the separation of CO2 from N2 when compared with SILMs using the same PVDF support but with different ionic liquids. PMID:25594165

  5. Supported Ionic Liquid Membranes and Ion-Jelly Membranes with [BMIM][DCA]: Comparison of Its Performance for CO2 Separation

    PubMed Central

    Couto, Ricardo; Neves, Lusa; Simes, Pedro; Coelhoso, Isabel

    2015-01-01

    In this work, a supported ionic liquid membrane (SILM) was prepared by impregnating a PVDF membrane with 1-butyl-3-methylimidazolium dicyanamide ([BMIM][DCA]) ionic liquid. This membrane was tested for its permeability to pure gases (CO2, N2 and O2) and ideal selectivities were calculated. The SILM performance was also compared to that of Ion-Jelly membranes, a new type of gelled membranes developed recently. It was found that the PVDF membrane presents permeabilities for pure gases similar or lower to those presented by the Ion-Jelly membranes, but with increased ideal selectivities. This membrane presents also the highest ideal selectivity (73) for the separation of CO2 from N2 when compared with SILMs using the same PVDF support but with different ionic liquids. PMID:25594165

  6. The influence of reduction methods and conditions on the activity of alumina-supported platinum catalysts for the liquid phase hydrogenation of benzaldehyde in ethanol

    SciTech Connect

    Arai, M.; Obata, A.; Nishiyama, Y.

    1997-02-01

    The activities of supported metal catalysts depend on various preparation variables, including the method of reduction. A variety of reduction procedures can be applied to the preparation of supported metal catalysts. Previously, the authors used a solid-liquid reduction by sodium tetrahydroborate solution for preparing supported platinum catalysts. In this reduction, platinum precursors adsorbed on supports were brought into contact with the reducing solution. The alumina-supported platinum catalysts prepared in this way were found to display interesting activities in the liquid-phase hydrogenation of {alpha},{beta}-unsaturated aldehydes; they were highly selective to the formation of unsaturated alcohols. The selective hydrogenation of C=O bonds of {alpha},{beta}-unsaturated aldehydes is difficult to achieve with platinum catalysts without using some additives like tin and iron. The maximum temperature that the supported platinum catalysts went through was 110{degrees}C, required for the removal of water. This thermal history is a possible reason for the catalytic activity observed. Following those observations, in the present work, the authors have further examined the influence of reduction procedures by using hydrazine as well as sodium tetrahydroborate and different temperatures common during gas-phase reduction with hydrogen. The catalytic activity has been tested by the liquid-phase hydrogenation of benzaldehyde (BAL) in ethanol under mild conditions. 12 refs., 3 figs.

  7. Ultra-fine Pt nanoparticles supported on ionic liquid polymer-functionalized ordered mesoporous carbons for nonenzymatic hydrogen peroxide detection.

    PubMed

    Bo, Xiangjie; Bai, Jing; Qi, Bin; Guo, Liping

    2011-10-15

    Poly(ionic liquid) (PIL) coated ordered mesoporous carbons (OMCs) were prepared by in situ polymerization of 3-ethyl-1-vinylimidazolium tetrafluoroborate ([VEIM]BF(4)) monomer on OMCs matrix. PIL on the surface of OMCs can provide sufficient binding sites to anchor the precursors of metal ion. PIL/OMCs were employed as support material for the deposition and formation of ultra-fine Pt nanoparticles, via the self-assembly between the negative Pt precursor and positively charged functional groups of PIL-functionalized OMCs. The combination of the unique properties of each component endows Pt/PIL/OMCs as a good electrode material. Compared with the Pt/OMCs nanocomposite, the Pt/PIL/OMCs modified electrode displays high electrocatalytic activity towards hydrogen peroxide (H(2)O(2)) and gives linear range from 1.0 10(-7) to 3.2 10(-3) M (R=0.999). The Pt/PIL/OMCs responds very rapidly to the changes in the level of H(2)O(2), producing steady-state signals within 4-5s. A high sensitivity of 24.43 ?A mM(-1) and low detection limit of 0.08 ?M was obtained at Pt/PIL/OMCs modified electrode towards the reduction of H(2)O(2). The improved activity makes Pt/PIL/OMCs nanocomposite promising for being developed as an attractive robust and new electrode material for electrochemical sensors and biosensors design. PMID:21784627

  8. Immobilization of Candida rugosa lipase onto an eco-friendly support in the presence of ionic liquid.

    PubMed

    Cabrera-Padilla, Rebeca Y; Lisboa, Milena C; Pereira, Matheus M; Figueiredo, Renan T; Franceschi, Elton; Fricks, Alini T; Lima, lvaro S; Silva, Daniel P; Soares, Cleide M F

    2015-05-01

    Candida rugosa lipase (CRL) was immobilized on an eco-friendly support poly(3-hydroxybutyrate-co-hydroxyvalerate) (PHBV), by physical adsorption, using different ionic liquids (ILs) as immobilization additives. This was to investigate the influence of cationic core ([C4mpy]Cl, [C4min]Cl), of anions ([C4min]Cl, [C4min]N(CN)2, [C4min]Tf2N), and of cation chain length ([C2min]Tf2N, [C4min]Tf2N) in the immobilization process. The immobilized biocatalysts (IB) were characterized with respect to the morphological, physico-chemical properties, total activity recovery yield (Ya), and biochemical properties of more efficient IB were evaluated. Initially, it was found that the change of cationic core did not influence in Ya compared to the control. With change of anions, it was seen that the best result was obtained for the more hydrophobic anion (Tf2N), and finally increasing the cation chain length increased Ya. IB most efficient with [C4min]Tf2N obtained 78% of Ya, more than twice the control value (30%) and a considerable enhancement of operational stability compared with the control. PMID:25391807

  9. Determination of selected pharmaceutical compounds in biosolids by supported liquid extraction and gas chromatography-tandem mass spectrometry.

    PubMed

    Albero, Beatriz; Snchez-Brunete, Consuelo; Miguel, Esther; Aznar, Ramn; Tadeo, Jos L

    2014-04-01

    In this work, an analytical method was developed for the determination of pharmaceutical drugs in biosolids. Samples were extracted with an acidic mixture of water and acetone (1:2, v/v) and supported liquid extraction was used for the clean-up of extracts, eluting with ethyl acetate:methanol (90:10, v/v). The compounds were determined by gas chromatography-tandem mass spectrometry using matrix-match calibration after silylation to form their t-butyldimethylsilyl derivatives. This method presents various advantages, such as a fairly simple operation for the analysis of complex matrices, the use of inexpensive glassware and low solvent volumes. Satisfactory mean recoveries were obtained with the developed method ranging from 70 to 120% with relative standard deviations (RSDs) ? 13%, and limits of detection between 0.5 and 3.6 ng g(-1). The method was then successfully applied to biosolids samples collected in Madrid and Catalonia (Spain). Eleven of the sixteen target compounds were detected in the studied samples, at levels up to 1.1 ?g g(-1) (salicylic acid). Ibuprofen, caffeine, paracetamol and fenofibrate were detected in all of the samples analyzed. PMID:24582395

  10. Supported phospholipid bilayer interaction with components found in typical room-temperature ionic liquids - a QCM-D and AFM study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quartz crystal microbalance with dissipation monitoring and atomic force microscopy were combined to evaluate the defects created by room-temperature ionic liquid anion and cation in a supported phospholipid bilayer composed of Zwitterionic lipids on a silica surface. The cation 1-octyl-3-methyl im...

  11. Utilization of liquid human wastes and introduction into the material cycling in biological life-support systems

    NASA Astrophysics Data System (ADS)

    Kovaleva, N. P.>; Ushakova, S. A.; Gribovskaya, I. V.; Kudenko, U. A.

    The possibilities of step-by-step utilization of liquid human wastes in biological life-support systems on long-functioning space stations have been considered in this work. Utilization involves "wet" urine incineration with hydrogen peroxide at normal pressure and 90 - 95°C temperature, urease-enzymic decomposition of urine and biological desalination in the higher plant link. The soybean flour was used as a source of urease. Growing soya plants as a component of the higher plant link would give a steady source of urease to the system. To decompose urea (9-15g) contained in 1l of incinerated urine we used 0.5 - 1 g of soy flour. The duration of hydrolysis of daily urea excreted by a human is 70 - 95 hours. It is supposed that ammonia excreted in the reaction of urea decomposition will be processed by nitrifying bacteria. The concentration of total nitrogen in urine after urea hydrolysis and removal of ammonia formed during the reaction constituted 0.6 - 1.2 g/l. Further biological desalination was carried out in the higher plant link, for that the edible salt-accumulating halophytes Salicornia europaea were used. To grow this plant under the aqueous culture conditions, the urine was additionally mineralized at 180 °C after incineration and decomposition of urea. The process of additional mineralization was related to the necessity of removal of organic materials and nitrogen residues, which higher concentration under the aqueous culture conditions has negative effect on plants. The volume of the nutrient solution for growing 6 plants of Salicornia europaea was 1.5 l (daily norm of urine excreted by human), the planting area was 0.032 m2. By the end of vegetation the productivity and mineral composition of Salicornia europaea plants were analyzed. The productivity of plants grown on liquid human wastes (the experiment) practically was not different from the productivity of plants grown on the mineral solution with sodium chloride (checkout). In experimental plants the content of potassium increased on 30% and the sodium content decreased on 30% as compared to the check plants. As a result the NaCl content constituted 23% of dry plant mass. The variant making the additional mineralization of urine at 180 °C avoidable has been considered in this work as well. For this purpose the technology of substrate growing of Salicornia europaea plants and intermittent introduction of urine during vegetation after "wet" incineration and urease-enzymatic decomposition of urea has been introduced.

  12. Influence of the extractant on strontium transport from reprocessing concentrate solutions through flat-sheet supported liquid membranes

    SciTech Connect

    Dozol, J.F.; Casas, J.; Sastre, A.M.

    1994-10-01

    The influence of the extractant on strontium transport through a flat-sheet-supported liquid membrane from nuclear fuel reprocessing concentrate solutions to demineralized water has been studied using two crown ethers of different lipophilicity: dicyclohexano-18-crown-6 (DC18C6) and di-tert-butylcyclohexano-18-crown-6 (DtBuC18C6). The distribution coefficients of strontium showed that DC18C6 is a better strontium extractant than DtBuC18C6 in the entire range of crown-ether concentration studied. No effect of association between the DC18C6 molecules was observed even at high concentrations. However, the strong lipophilic character of DtBuC18C6 led to a distribution coefficient of this extractant 10 times higher than the distribution coefficient of DC18C6. Thus, the membrane concentration of DtBuC18C6 was approximately 10 times higher than that of DC18C6. This leads to greater strontium permeability for DtBuC18C6, even though DC18C6 had a greater capacity for strontium extraction and a higher diffusion coefficient in the membrane due to the smaller molar volume of this crown ether. The precipitation of a white solid was observed when the synthetic concentrate was mixed with an organic phase containing DtBuC18C6 dissolved in n-hexylbenzene (0.7 mol{center_dot}L{sup {minus}1} isotridecanol), causing a decrease of strontium permeability. In this case, DC18C6 had the greatest strontium permeability.

  13. A liquid-supported condensation of major minerals in the solar nebula: Evidence from glasses in the Kaba (CV3) chondrite

    NASA Astrophysics Data System (ADS)

    Varela, M. E.; Kurat, G.; Zinner, E.

    2005-11-01

    Glasses, in the Kaba CV3 chondrite, occur as mesostasis in chondrules and aggregates and as inclusions in olivines, both confined or open and connected to the mesostasis. The inclusions in olivine and the glassy mesostasis of aggregates seem to have formed contemporaneously. The confined glass inclusions and open inclusions in olivine were formed during olivine growth and the mesostasis glass during olivine aggregation. All glasses have high trace element contents ( 10-20CI) with unfractionated CI-normalized abundances of refractory trace elements. In contrast, V, Mn, Li, and Cr are depleted in all glasses with respect to the refractory trace elements, as is Rb in the glass inclusions in olivine but not in the mesostasis glass. This abundance pattern indicates vapor fractionation and a common condensation origin for both glasses. Glasses of confined glass inclusions in olivine have a Si sbnd Al sbnd Ca-rich composition with a chondritic Ca/Al ratio. Glasses of open glass inclusions and mesostasis are poor in Ca and enriched in alkalis. However, Ca contents of olivines indicate crystallization from a Ca-rich melt of a composition similar to that of the glass inclusions. In addition, trace element abundances indicate that these glasses (liquids) probably had an original composition similar to that of the inclusion glass. They apparently lost Ca in exchange for alkalis in a metasomatic exchange reaction, presumably with the vapor. There is now growing evidence that liquids can indeed condense from a solar nebula gas, provided the gas/dust ratio is sufficiently low. In these regions with enhanced oxygen fugacity as compared to that of a nebula of solar composition, liquids (the glass precursor) probably played an important role in growing crystals from the vapor by liquid-phase epitaxy. The glasses appear to be the remnants of this thin liquid layer interface that supported the growth of olivine from the vapor following the Vapor-Liquid-Solid process. This liquid will have a refractory composition and will have trace element contents which are in equilibrium with the vapor, and, therefore, will not change much during the time of olivine growth. The composition of the liquid seems to be unconstrained by the phases it is in contact with. Samples of this liquid will be retained as glass inclusions in olivine. The glassy mesostasis could also be a sample of this liquid that got trapped in inter-crystal spaces. The mesostasis glass subsequently behaved as an open system and its Ca was exchangedpresumably with the vaporfor the alkali elements Na, K, and Rb. In contrast, glass inclusions in olivine were protected by the host, could not react, and thus preserved the original composition of this liquid.

  14. Pumice-supported Pd-Pt bimetallic catalysts: Synthesis, structural characterization, and liquid-phase hydrogenation of 1,3-cyclooctadiene

    SciTech Connect

    Deganello, G.; Duca, D.; Liotta, L.F.; Martorana, A.; Venezia, M.; Benedetti, A.; Fagherazz, G.

    1995-01-01

    A series of pumice-supported palladium-platinum bimetallic catalysts were prepared and investigated by X-ray scattering (WAXS and SAXS) and XPS techniques. An alloy Pd-Pt was formed. The less abundant metal was found to segregate to the surface. The catalysts were tested in the liquid-phase hydrogenation of 1,3-cyclooctadiene to cyclooctene, and compared with similarly prepared pumice-supported palladium and platinum catalysts and other supported Pd-Pt catalysts reported in the literature. The addition of platinum reduces the activity and the selectivity of the palladium catalysts. Differences between the activity of these pumice-supported catalysts and the activity of previously described Pd and Pd-Pt catalysts on other supports, are attributed to the presence, in the latter, of diffusional processes. 50 refs., 4 figs. 2 tabs.

  15. Development of supported liquid membrane techniques for the monitoring of trace levels of organic pollutants in wastewaters and water purification systems

    NASA Astrophysics Data System (ADS)

    Msagati, Titus A. M.; Mamba, Bhekie B.

    The supported liquid membrane (SLM) extraction technique has been developed and successfully used for the monitoring of trace quantities of ionisable organic contaminants, including 17?-estradiol and its metabolites, testosterones and their methyl ester derivatives, benzimidazole anthelmintic antibiotics and sulphonamides in aquatic systems. A number of parameters which control the mass transfer in the supported liquid membrane extraction process such as donor and acceptor pH, extraction time and the type of organic liquid membrane were optimised to enhance the efficiency of the liquid membrane in the removal of these compounds. The method developed gave very low detection limits (0.3 ng/l to 2.4 ng/l for 17?-estradiol and its metabolites; between 1 ?g/l and 20 ?g/l for sulphonamides; and between 0.1 ng/l and 10 ng/l for benzimidazole anthelmintic compounds). The SLM method showed good linearity, reproducibility and repeatability values and is therefore suitable for routine monitoring of such compounds in water and wastewater systems.

  16. Supported liquid membrane based removal of lead(II) and cadmium(II) from mixed feed: Conversion to solid waste by precipitation.

    PubMed

    Bhatluri, Kamal Kumar; Manna, Mriganka Sekhar; Ghoshal, Aloke Kumar; Saha, Prabirkumar

    2015-12-15

    Simultaneous removal of two heavy metals, lead(II) and cadmium(II), from mixed feed using supported liquid membrane (SLM) based technique is investigated in this work. The carrier-solvent combination of "sodium salt of Di-2-ethylhexylphosphoric acid (D2EHPA) (4% w/w) in environmentally benign coconut oil" was immobilized into the pores of solid polymeric polyvinylidene fluoride (PVDF) support. Sodium carbonate (Na2CO3) was used as the stripping agent. Carbonate salts of lead(II) and cadmium(II) were formed in the stripping side interface and they were insoluble in water leading to precipitation inside the stripping solution. The transportation of solute is positively affected due to the precipitation. Lead(II) removal was found to be preferential due to its favorable electronic configuration. The conversion of the liquid waste to the solid one was added advantage for the final removal of hazardous heavy metals. PMID:26252994

  17. Analysis of the organic liquid produced from catalytic cracking of crude palm oil in the presence of alumina supported catalysts

    NASA Astrophysics Data System (ADS)

    Ramli, Anita; Razak, Rozlina Abdul

    2012-09-01

    Catalytic cracking of crude palm oil (CPO) was studied in the presence of alumina, 1% Pt/Al2O3 and 1% Pd/Al2O3 as catalyst. The CPO to catalyst weight ratio used was 1:0.05. The experiment was carried out in a simple liquid-phase batch reactor at atmospheric pressure where the sample was heated to 300-350 δC. Products formed were organic liquid products (OLP) and gaseous product with the solid residue remains in the reactor. The total conversion of CPO was only between 25 - 31% where the residue is suggested to be mainly of polimerised CPO. The OLP was analysed using a gas chromatography with FID detector. Analyses show that the selectivity to liquid fuel is influence by the catalyst used whereby Al2O3 gives the highest selectivity to gasoline while 1% Pt/Al2O3 has the highest selectivity to diesel. However, 1% Pd/Al2O3 is not a suitable catalyst for catalytic cracking of CPO to liquid fuel where less than 17.5% of OLP produced could be classified as liquid fuel.

  18. Synthesis, structural, photophysical and electrochemical studies of various d-metal complexes of btp [2,6-bis(1,2,3-triazol-4-yl)pyridine] ligands that give rise to the formation of metallo-supramolecular gels.

    PubMed

    Byrne, Joseph P; Kitchen, Jonathan A; Kotova, Oxana; Leigh, Vivienne; Bell, Alan P; Boland, John J; Albrecht, Martin; Gunnlaugsson, Thorfinnur

    2014-01-01

    2,6-Bis(1,2,3-triazol-4-yl)pyridine (btp) is a terdentate binding motif that is synthesised modularly via the CuAAC reaction. Herein, we present the synthesis of ligands 1 and 2 and the investigation of the coordination chemistry, photophysical behaviour and electrochemistry of complexes of these with a number of d-metal ions (e.g. Ru(II), Ir(III), Ni(II) and Pt(II)). The X-ray crystal structures of ligand 1 and the complexes [Ru2(2)](PF6)Cl, [Ni1(2)](PF6)Cl and [Ir1Cl3] are also presented. All of the complexes displayed non-classical triazolyl C-HCl(-) hydrogen bonding. All but one complex showed no metal-based luminescence at room temperature, while all of the Pt(ii) complexes displayed luminescence at 77 K. The electrochemistry of the Ru(II) complexes was also studied and these complexes were found to have higher oxidation potentials than analogous compounds. The redox behaviour of [RuL2](2+) complexes with both 1 and 2 was nearly identical, while [Ru1Cl2(DMSO)] was oxidised at significantly lower potential. We also show that the Ru(II) complex of 2, [Ru2(2)](PF6)Cl, gave rise to the formation of a metallo-supramolecular gel, the morphology of which was studied using scanning electron and helium ion microscopy. PMID:24149846

  19. Design, testing, fabrication and launch support of a liquid chemical barium release payload (utilizing the liquid fluorine-barium salt/hydrazine system)

    NASA Technical Reports Server (NTRS)

    Stokes, C. S.; Smith, E. W.; Murphy, W. J.

    1972-01-01

    A payload was designed which included a cryogenic oxidizer tank, a fuel tank, and burner section. Release of 30 lb of chemicals was planned to occur in 2 seconds at the optimum oxidizer to fuel ratio. The chemicals consisted of 17 lb of liquid fluorine oxidizer and 13 lb of hydrazine-barium salt fuel mixture. The fuel mixture was 17% barium chloride, 16% barium nitrate, and 67% hydrazine, and contained 2.6 lb of available barium. Two significant problem areas were resolved during the program: explosive valve development and burner operation. The release payload was flight tested, from Wallops Island, Virginia. The release took place at an altitude of approximately 260 km. The release produced a luminous cloud which expanded very rapidly, disappearing to the human eye in about 20 seconds. Barium ion concentration slowly increased over a wide area of sky until measurements were discontinued at sunrise (about 30 minutes).

  20. Comparative Study on the Sulfur Tolerance and Carbon Resistance of Supported Noble Metal Catalysts in Steam Reforming of Liquid Hydrocarbon Fuel

    SciTech Connect

    Xie, Chao; Chen, Yongsheng; Engelhard, Mark H.; Song, Chunshan

    2012-04-18

    This work was conducted to clarify the influence of the type of metal and support on the sulfur tolerance and carbon resistance of supported noble metal catalysts in steam reforming of liquid hydrocarbons. Al2O3-supported noble metal catalysts (Rh, Ru, Pt, and Pd), Rh catalysts on different supports (Al2O3, CeO2, SiO2, and MgO), and Pt catalyst supported on CeO2 and Al2O3, were examined for steam reforming of a liquid hydrocarbon fuel (Norpar13 from Exxon Mobil) at 800 C for 55 h. The results indicate that (1) Rh/Al2O3 shows higher sulfur tolerance than the Ru, Pt, and Pd catalysts on the same support; (2) both Al2O3 and CeO2 are promising supports for Rh catalyst to process sulfur-containing hydrocarbons; and (3) Pt/CeO2 exhibits better catalytic performance than Pt/Al2O3 in the reaction with sulfur. TEM results demonstrate that the metal particles in Rh/Al2O3 were better dispersed (mostly in 1-3 nm) compared with the other catalysts after reforming the sulfur-containing feed. As revealed by XPS, the binding energy of Rh 3d for Rh/Al2O3 is notably higher than that for Rh/CeO2, implying the formation of electron-deficient Rh particles in the former. The strong sulfur tolerance of Rh/Al2O3 may be related to the formation of well-dispersed electron-deficient Rh particles on the Al2O3 support. Sulfur K-edge XANES illustrates the preferential formation of sulfonate and sulfate on Rh/Al2O3, which is believed to be beneficial for improving its sulfur tolerance as their oxygen-shielded sulfur structure may hinder direct Rh-S interaction. Due to its strong sulfur tolerance, the carbon deposition on Rh/Al2O3 was significantly lower than that on the Al2O3-supported Ru, Pt, and Pd catalysts after the reaction with sulfur. The superior catalytic performance of CeO2-supported Rh and Pt catalysts in the presence of sulfur can be ascribed mainly to the promotion effect of CeO2 on carbon gasification, leading to much lower carbon deposition compared with the Rh/Al2O3, Rh/MgO, Rh/SiO2 and Pt/Al2O3 catalysts.

  1. Novel supports in chiral stationary phase development for liquid chromatography. Preparation, characterization and application of ordered mesoporous silica particles.

    PubMed

    Sierra, Isabel; Prez-Quintanilla, Damin; Morante, Sonia; Gan, Judith

    2014-10-10

    Recent advances in the development of new materials are having a major impact on analytical chemistry. For example, the unique properties of ordered mesoporous silicas (OMSs) have been shown to enhance the analytical performance of many existing techniques or allow new, exciting ones to be developed. Likewise, the introduction of organo-functional groups makes OMSs highly versatile and enables them to perform specialized tasks, such as the separation of chiral compounds. This review provides an overview with the most relevant achievements in the preparation of OMS particles functionalized with chiral selectors. In addition, some examples from the last fifteen years regarding the analytical applications of functionalized OMS for chiral separations by high-performance liquid chromatography, ultra-high pressure high-performance liquid chromatography and capillary electrochromatography have been reviewed. PMID:25015243

  2. Voltammetric and reference microelectrodes with integrated microchannels for flow through microvoltammetry. 2. Coupling the microcell to a supported liquid membrane preconcentration technique

    PubMed

    Keller; Buffle

    2000-03-01

    The paper describes the assembly and functioning of the microvoltammetric cell described in Part 1, with a hollow Fiber Supported Liquid Membrane (HFSLM), for trace metal analysis. Membrane stability, working-electrode behavior, mercury-film lifetime inside the HFSLM, hydrodynamic conditions, as well as transport kinetics of the metal through the SLM have been studied in detail. System calibrations have been performed in the range 5-120 nM Pb(II). The reproducibility and sensitivity of the whole microsystem is discussed as well as limitations and possible improvements. PMID:10739196

  3. Preparation of Poly(ionic liquid)s-Supported Recyclable Organocatalysts for the Asymmetric Nitroaldol (Henry) Reaction.

    PubMed

    Groeheilmann, Julia; Bandomir, Jenny; Kragl, Udo

    2015-12-21

    A novel strategy for the embedding of quinine-based organocatalysts in polymerized ionic liquids-based hydrogels is presented. With this technique, the encapsulated organocatalyst was successfully recovered and reused for four cycles without any loss of enantioselectivity (up to 91?% ee) for the asymmetric nitroaldol (Henry) reaction. In this study, high catalyst leaching was significantly reduced (<0.01?%) by controlling the water content. After catalyst removal, evaporation of the solvent affords the product in 98?% purity without any further purification. PMID:26526874

  4. Determination of phenolic acids and flavonoids in raw propolis by silica-supported ionic liquid-based matrix solid phase dispersion extraction high performance liquid chromatography-diode array detection.

    PubMed

    Wang, Zhibing; Sun, Rui; Wang, Yuanpeng; Li, Na; Lei, Lei; Yang, Xiao; Yu, Aimin; Qiu, Fangping; Zhang, Hanqi

    2014-10-15

    The silica-supported ionic liquid (S-SIL) was prepared by impregnation and used as the dispersion adsorbent of matrix solid phase dispersion (MSPD) for the simultaneous extraction of eight phenolic acids and flavonoids, including caffeic acid, ferulic acid, morin, luteolin, quercetin, apigenin, chrysin, and kaempferide in raw propolis. High performance liquid chromatography with a Zorbax SB-C18 column (150mm4.6mm, 3.5?m) was used for separation of the analytes. The mobile phase consisted of 0.2% phosphoric acid aqueous solution and acetonitrile and the flow rate of the mobile phase was 0.5mL/min. The experimental conditions for silica-supported ionic liquid-based matrix solid phase dispersion (S-SIL-based MSPD) were optimized. S-SIL containing 10% [C6MIM]Cl was used as dispersant, 20mL of n-hexane as washing solvent and 15mL of methanol as elution solvent. The ratio of S-SIL to sample was selected to be 4:1. The standard curves showed good linear relationship (r>0.9995). The limits of detection and quantification were in the range of 5.8-22.2ngmL(-1) and 19.2-74.0ngmL(-1), respectively. The relative standard deviations (RSDs) of intra-day and inter-day determination were lower than 8.80% and 11.19%, respectively. The recoveries were between 65.51% and 92.32% with RSDs lower than 8.95%. Compared with ultrasound-assisted extraction (UAE) and soxhlet extraction, the present method consumed less sample, organic solvent, and extraction time, although the extraction yields obtained by S-SIL-based MSPD are slightly lower than those obtained by UAE. PMID:25190186

  5. Separation of CO{sub 2} from CO{sub 2}/N{sub 2} mixture using supported polymeric liquid membranes at elevated temperatures

    SciTech Connect

    Jeong, S.H.; Lee, K.H.

    1999-09-01

    Novel supported polymeric liquid (SPL) membranes have been prepared and shown to be applicable for the separation of CO{sub 2} from mixtures with N{sub 2} at the elevated temperature encountered in flue gas. The membranes were fabricated by immobilizing polystyrene, polyethylene, and polydimethylsiloxane into the pores of borosilicate glass supports. At 250 C, the CO{sub 2} permeability and CO{sub 2}/N{sub 2} separation factors were 3000--9000 barrer and 1.7--3.7, respectively. It was shown that polymers which have a lower T{sub g} or melting temperature than the operating temperature can be used as SPL membrane materials at elevated temperatures.

  6. Lanthanide directed self-assembly of highly luminescent supramolecular "peptide" bundles from ?-amino acid functionalized 2,6-bis(1,2,3-triazol-4-yl)pyridine (btp) ligands.

    PubMed

    Byrne, Joseph P; Kitchen, Jonathan A; O'Brien, John E; Peacock, Robert D; Gunnlaugsson, Thorfinnur

    2015-02-16

    Ligands containing the [2,6-bis(1,2,3-triazol-4-yl)pyridine] (btp) motif have recently shown promise in coordination chemistry. The motif is synthesized via the Cu(I)-catalyzed "click" reaction and can be conveniently functionalized when compared to other terdentate chelating motifs. Ligand 1 was synthesized and shown to sensitize Eu(III) and Tb(III) excited states effectively. The use of these ions to synthesize self-assembly structures in solution was investigated by carrying out both (1)H NMR and photophysical titrations. The latter were used to determine high binding constants from changes in the absorption, ligand emission (fluorescence), and lanthanide-centered emission. A small library of amino acid derivatives of 1, ligands 3, were prepared upon coupling reactions with Gly, Ala, Phe, and Trp methyl esters, with a view to introducing biologically relevant and chiral moieties into such ligands. All of these derivatives were shown to form stable, emissive Ln(III) self-assemblies, emitting in the millisecond time range, which were studied by means of probing their photophysical properties in organic solutions using lanthanide ion titrations. All the Tb(III) complexes, with the exception of Trp based derivatives, gave rise to highly luminescent and bright complexes, with quantum yields of Tb(III) emission of 46-70% in CH3CN solution. In contrast, the Eu(III) complexes gave rise to more modest quantum yields of 0.3-3%, reflecting better energy match for the Tb(III) complexes, and hence, more efficient sensitization, as demonstrated by using low temperature measurements to determine the triplet state of 1. PMID:25634622

  7. Role of diluent on the separation of 90Y from 90Sr by solvent extraction and supported liquid membrane using T2EHDGA as the extractant.

    PubMed

    Dutta, S; Raut, D R; Mohapatra, P K

    2012-04-01

    The separation behaviour of (90)Y from (90)Sr was investigated by diluent variation using solvent extraction and supported liquid membrane techniques employing N,N,N',N'-tetra-2-ethylhexyldiglycolamide (T2EHDGA) as the extractant. Both D(Y) (distribution ratio of Y(III)) and S.F. (separation factor) were found to be high in the solvent extraction studies when chloroform was used as the diluent. Subsequent supported liquid membrane (SLM) studies using PTFE flat sheet membranes containing 0.2M T2EHDGA in various diluents indicated the trend of Y transport as xylene>hexone>chloroform>carbon tetrachloride>n-dodecane+30% iso-decanol mixture. However, the Sr(II) transport rates were also high with xylene, hexone, and carbon tetrachloride as the diluents which led us to carry out subsequent studies using chloroform and n-dodecane+30% iso-decanol mixture. Acid variation studies in chloroform system indicated an interesting phenomena of increasing Y(III) transport and decreasing Sr(II) transport with increasing acid concentration. Separation of (90)Y from a mixture of (90)Sr and (90)Y was also attempted. PMID:22309631

  8. MEASUREMENTS TAKEN IN SUPPORT OF QUALIFICATION OF PROCESSING SAVANNAH RIVER SITE LOW-LEVEL LIQUID WASTE INTO SALTSTONE

    SciTech Connect

    Reigel, M.; Bibler, N.; Diprete, C.; Cozzi, A.; Staub, A.; Ray, J.

    2010-01-27

    The Saltstone Facility at the Savannah River Site (SRS) immobilizes low-level liquid waste into Saltstone to be disposed of in the Z-Area Saltstone Disposal Facility, Class Three Landfill. In order to meet the permit conditions and regulatory limits set by the South Carolina Department of Health and Environmental Control (SCDHEC), the Resource Conservation and Recovery Act (RCRA) and the Environmental Protection Agency (EPA), both the low-level salt solution and Saltstone samples are analyzed quarterly. Waste acceptance criteria (WAC) are designed to confirm the salt solution sample from the Tank Farm meets specific radioactive and chemical limits. The toxic characteristic leaching procedure (TCLP) is used to confirm that the treatment has immobilized the hazardous constituents of the salt solution. This paper discusses the methods used to characterize the salt solution and final Saltstone samples from 2007-2009.

  9. LIQUID PHASE SELECTIVE OXIDATION OF ETHYLBENZENE OVER ACTIVATED AL2O3 SUPPORTED V2O5 CATALYST

    EPA Science Inventory

    Acetophenone, a very useful industrial chemical for fragrance and flavoring agent and a solvent for plastics and resins, is usually produced as a byproduct of phenol production from cumeme. Aluminia supported vandium oxide catalyst is now explored for the selective oxidation of e...

  10. Partial oxidation of liquid hydrocarbons in the presence of oxygen-conducting supports: Effect of catalyst layer deposition

    SciTech Connect

    Smith, M.; Berry, D.; Shekhawt, D.; Haynes, D.; Spivey, J.

    2010-01-01

    Ni-substituted barium hexaaluminate (BNHA) catalysts supported onto gadolinium-doped ceria (GDC), an oxygen-conductor, were prepared using two different methods: (1) conventional incipient wetness impregnation (IWI), in which a non-porous GDC support was impregnated in the conventional manner with aqueous precursors, then dried and calcined to form a supported hexaaluminate, and (2) solid-state mixing (SSM), in which solid hexaaluminate and GDC particles were mechanically ground together and thermally treated to produce a final catalyst. These catalysts were compared to bulk, unsupported BNHA; 3 wt% Ni/alumina; and 3 wt% Ni/GDC (the latter two prepared by conventional impregnation) for the partial oxidation (POX) of n-tetradecane. The reaction studies included examining the effect of 50 ppm S as dibenzothiophene (DBT) and 5 wt% 1-methylnaphthalene (MN) on the product yield under POX conditions. Temperature programmed oxidation (TPO) was used to characterize carbon formation in the reactor. The materials were characterized by BET, ICP-OES, XRD, and SEM/EDS prior to the reaction tests. Characterization of the two GDC-supported BNHA catalysts prior to the reaction studies indicated no significant differences in the bulk composition, surface area, and crystal structure. However, SEM images showed a larger amount of exposed GDC support surface area for the material prepared by IWI. Both of the GDC-supported BNHA materials demonstrated greatly reduced deactivation, with significantly reduced carbon formation compared to bulk BNHA. This was attributed to the oxygen-conducting property of the GDC, which reduced the rate of deactivation of the reaction sites by DBT and MN. The material prepared by IWI demonstrated more stable hydrogen and carbon monoxide yield than the material prepared by SSM. Although both catalysts deactivated in the presence of DBT and MN, the activity of the catalyst prepared by IWI recovered activity more quickly after the contaminants were removed. This material also maintained >50% of its initial hydrogen yield for more than 4 h after exposure to DBT and MN, while the hydrogen for the material prepared by SSM dropped to this same level within 2 h. Incipient wetness impregnation appears to provide a higher degree of interaction between the oxygenconducting GDC support and the hexaaluminate, resulting in less rapid deactivation, which appears to be due primarily to carbon deposition.

  11. Automation of static and dynamic non-dispersive liquid phase microextraction. Part 2: Approaches based on impregnated membranes and porous supports.

    PubMed

    Alexovi?, Michal; Horstkotte, Burkhard; Solich, Petr; Sabo, Jn

    2016-02-11

    A critical overview on automation of modern liquid phase microextraction (LPME) approaches based on the liquid impregnation of porous sorbents and membranes is presented. It is the continuation of part 1, in which non-dispersive LPME techniques based on the use of the extraction phase (EP) in the form of drop, plug, film, or microflow have been surveyed. Compared to the approaches described in part 1, porous materials provide an improved support for the EP. Simultaneously they allow to enlarge its contact surface and to reduce the risk of loss by incident flow or by components of surrounding matrix. Solvent-impregnated membranes or hollow fibres are further ideally suited for analyte extraction with simultaneous or subsequent back-extraction. Their use can therefore improve the procedure robustness and reproducibility as well as it "opens the door" to the new operation modes and fields of application. However, additional work and time are required for membrane replacement and renewed impregnation. Automation of porous support-based and membrane-based approaches plays an important role in the achievement of better reliability, rapidness, and reproducibility compared to manual assays. Automated renewal of the extraction solvent and coupling of sample pretreatment with the detection instrumentation can be named as examples. The different LPME methodologies using impregnated membranes and porous supports for the extraction phase and the different strategies of their automation, and their analytical applications are comprehensively described and discussed in this part. Finally, an outlook on future demands and perspectives of LPME techniques from both parts as a promising area in the field of sample pretreatment is given. PMID:26802999

  12. Liquid-Phase Synthesis of 2'-Methyl-RNA on a Homostar Support through Organic-Solvent Nanofiltration.

    PubMed

    Gaffney, Piers R J; Kim, Jeong F; Valtcheva, Irina B; Williams, Glynn D; Anson, Mike S; Buswell, Andrew M; Livingston, Andrew G

    2015-06-22

    Due to the discovery of RNAi, oligonucleotides (oligos) have re-emerged as a major pharmaceutical target that may soon be required in ton quantities. However, it is questionable whether solid-phase oligo synthesis (SPOS) methods can provide a scalable synthesis. Liquid-phase oligo synthesis (LPOS) is intrinsically scalable and amenable to standard industrial batch synthesis techniques. However, most reported LPOS strategies rely upon at least one precipitation per chain extension cycle to separate the growing oligonucleotide from reaction debris. Precipitation can be difficult to develop and control on an industrial scale and, because many precipitations would be required to prepare a therapeutic oligonucleotide, we contend that this approach is not viable for large-scale industrial preparation. We are developing an LPOS synthetic strategy for 2'-methyl RNA phosphorothioate that is more amenable to standard batch production techniques, using organic solvent nanofiltration (OSN) as the critical scalable separation technology. We report the first LPOS-OSN preparation of a 2'-Me RNA phosphorothioate 9-mer, using commercial phosphoramidite monomers, and monitoring all reactions by HPLC, (31)P?NMR spectroscopy and MS. PMID:26012874

  13. Liquid-Phase Synthesis of 2′-Methyl-RNA on a Homostar Support through Organic-Solvent Nanofiltration

    PubMed Central

    Gaffney, Piers R J; Kim, Jeong F; Valtcheva, Irina B; Williams, Glynn D; Anson, Mike S; Buswell, Andrew M; Livingston, Andrew G

    2015-01-01

    Due to the discovery of RNAi, oligonucleotides (oligos) have re-emerged as a major pharmaceutical target that may soon be required in ton quantities. However, it is questionable whether solid-phase oligo synthesis (SPOS) methods can provide a scalable synthesis. Liquid-phase oligo synthesis (LPOS) is intrinsically scalable and amenable to standard industrial batch synthesis techniques. However, most reported LPOS strategies rely upon at least one precipitation per chain extension cycle to separate the growing oligonucleotide from reaction debris. Precipitation can be difficult to develop and control on an industrial scale and, because many precipitations would be required to prepare a therapeutic oligonucleotide, we contend that this approach is not viable for large-scale industrial preparation. We are developing an LPOS synthetic strategy for 2′-methyl RNA phosphorothioate that is more amenable to standard batch production techniques, using organic solvent nanofiltration (OSN) as the critical scalable separation technology. We report the first LPOS-OSN preparation of a 2′-Me RNA phosphorothioate 9-mer, using commercial phosphoramidite monomers, and monitoring all reactions by HPLC, 31P NMR spectroscopy and MS. PMID:26012874

  14. Core-Shell Diamond as a Support for Solid-Phase Extraction and High-Performance Liquid Chromatography

    SciTech Connect

    Saini, Gaurav; Jensen, David S.; Wiest, Landon A.; Vail, Michael A.; Dadson, Andrew; Lee, Milton L.; Shutthanandan, V.; Linford, Matthew R.

    2010-06-01

    We report the formation of core-shell diamond particles for solid phase extraction (SPE) and high performance liquid chromatography (HPLC) made by layer-by-layer (LbL) deposition. Their synthesis begins with the amine functionalization of microdiamond by its immersion in an aqueous solution of a primary amine-containing polymer (polyallylamine (PAAm)). The amine-terminated microdiamond is then immersed in an aqueous suspension of nanodiamond, which leads to adsorption of the nanodiamond. Alternating (self-limiting) immersions in the solutions of the amine-containing polymer and the suspension of nanodiamond are continued until the desired number of nanodiamond layers is formed around the microdiamond. Finally, the core-shell particles are cross-linked with 1,2,5,6-diepoxycyclooctane or reacted with 1,2-epoxyoctadecane. Layer-by-layer deposition of PAAm and nanodiamond is also studied on planar Si/SiO2 surfaces, which were characterized by SEM, Rutherford backscattering spectrometry (RBS) and nuclear reaction analysis (NRA). Core-shell particles are characterized by diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), environmental scanning electron microscopy (ESEM), and Brunauer Emmett Teller (BET) surface area and pore size measurements. Larger (ca. 50 μm) core-shell diamond particles have much higher surface areas, and analyte loading capacities in SPE than nonporous solid diamond particles. Smaller (ca. 3 μm), normal and reversed phase, core-shell diamond particles have been used for HPLC, with 36,300 plates per meter for mesitylene in a separation of benzene and alkyl benzenes on a C18 adsorbent, and 54,800 plates per meter for diazinon in a similar separation of two pesticides.

  15. Core-shell diamond as a support for solid-phase extraction and high-performance liquid chromatography.

    PubMed

    Saini, Gaurav; Jensen, David S; Wiest, Landon A; Vail, Michael A; Dadson, Andrew; Lee, Milton L; Shutthanandan, V; Linford, Matthew R

    2010-06-01

    We report the formation of core-shell diamond particles for solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) made by layer-by-layer (LbL) deposition. Their synthesis begins with the amine functionalization of microdiamond by its immersion in an aqueous solution of a primary amine-containing polymer (polyallylamine (PAAm)). The amine-terminated microdiamond is then immersed in an aqueous suspension of nanodiamond, which leads to adsorption of the nanodiamond. Alternating (self-limiting) immersions in the solutions of the amine-containing polymer and the suspension of nanodiamond are continued until the desired number of nanodiamond layers is formed around the microdiamond. Finally, the core-shell particles are cross-linked with 1,2,5,6-diepoxycyclooctane or reacted with 1,2-epoxyoctadecane. Layer-by-layer deposition of PAAm and nanodiamond is also studied on planar Si/SiO(2) surfaces, which were characterized by scanning electron microscopy (SEM), Rutherford backscattering spectrometry (RBS), and nuclear reaction analysis (NRA). Core-shell particles are characterized by diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), environmental scanning electron microscopy (ESEM), and Brunauer-Emmett-Teller (BET) surface area and pore size measurements. Larger (ca. 50 microm) core-shell diamond particles have much higher surface areas and analyte loading capacities in SPE than nonporous solid diamond particles. Smaller (ca. 3 microm), normal and reversed-phase, core-shell diamond particles have been used for HPLC, with 36,300 plates/m for mesitylene in a separation of benzene and alkyl benzenes and 54,800 plates/m for diazinon in a similar separation of two pesticides on a C(18) adsorbent. PMID:20446670

  16. Permeation of mixtures of four phenols through a supported liquid membrane in NaCl 1.0 mol/dm{sup 3} medium

    SciTech Connect

    Arana, G.; Borge, G.; Etxebarria, N.; Fernandez, L.A.

    1999-02-01

    The permeation of four phenols (phenol, 2-chlorophenol, 2-nitrophenol, and 2,4-dichlorophenol) through a supported liquid membrane has been studied in NaCl 1.0 mol/dm{sup 3} medium. The flux of each phenol was determined by measuring in real time the change of their concentration in the strip phase by making use of a fiber optic spectrophotometer and a multivariate calibration. The model for the permeation of phenol alone was first developed by making permeation experiments of a phenol, and then permeation studies of the mixture were carried out and the model was extended to those phenols. It was found that the permeation of a phenol is interfered with by the presence of other phenols.

  17. Automatic Supported Liquid Extraction (SLE) Coupled with HILIC-MS/MS: An Application to Method Development and Validation of Erlotinib in Human Plasma

    PubMed Central

    Pan, Jiongwei; Jiang, Xiangyu; Chen, Yu-Luan

    2010-01-01

    A novel bioanalytical method was developed and validated for the quantitative determination of erlotinib in human plasma by using the supported liquid extraction (SLE) sample cleanup coupled with hydrophilic interaction liquid chromatography and tandem mass spectrometric detection (HILIC-MS/MS). The SLE extract could be directly injected into the HILIC-MS/MS system for analysis without the solvent evaporation and reconstitution steps. Therefore, the method is simple and rapid. In the present method, erlotinib-d6 was used as the internal standard. The SLE extraction recovery was 101.3%. The validated linear curve range was 2 to 2,000 ng/mL based on a sample volume of 0.100-mL, with a linear correlation coefficient of > 0.999. The validation results demonstrated that the present method gave a satisfactory precision and accuracy: intra-day CV < 5.9% (<8.4% for the lower limit of quantitation, LLOQ) with n = 6 and the accuracy of 98.0106.0%; inter-day CV < 3.2% (<1.5% for LLOQ) with n = 18 and the accuracy of 100.0103.2%. A dilution factor of 10 with blank plasma was validated for partial volume analysis. The stability tests indicated that the erlotinib in human plasma is stable for three freeze-thaw cycles (100.0104.5% of the nominal values), or 24-h ambient storage (100.0104.8% of the nominal values), or 227-day frozen storage at both -20 C (91.594.5% of the nominal values) and -70 C (93.393.8% of the nominal values). The results also showed no significant matrix effect (<6.3%) even with direct injection of organic extract into the LC-MS/MS system. The validated method has been successfully applied to support a clinical study.

  18. ?-Radiolysis of ionic liquid irradiated with helium ion beam and the influence of radiolytic products on Dy3+ extraction.

    PubMed

    Ao, Yinyong; Zhou, Hanyang; Yuan, Weijin; Wang, Shuojue; Peng, Jing; Zhai, Maolin; Wang, Jianyong; Zhao, Ziqiang; Zhao, Long; Wei, Yuezhou

    2014-04-14

    Helium ion (He(+)) beam produced by a heavy ion linear accelerator was used to simulate ?-rays for studying the radiation effect on 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquid ([C4mim][NTf2]). The water-soluble radiolytic products of [C4mim][NTf2] under He(+) beam irradiation were analysed, and it was found that they were similar to those by ?-ray irradiation, but their amount was much less than that by ?-ray irradiation, which was attributed to the recombination of [C4mim][NTf2] radical cations in track by high linear energy transfer (LET) radiations of the He(+) beam. The extracting behaviour of Dy(3+) using irradiated [C4mim][NTf2] in combination with alkylated bis-triazinyl-pyridine (CA-BTP) was assessed, and found that the influence of He(+) beam on the extraction was less than that of ?-ray irradiation. In addition, radiolytic products have a different influence on Dy(3+) extraction at different doses; Dy(3+) partitioning decreases at 50 kGy due to the protonation of CA-BTP and the inhibition of cation exchange mechanism by radiation-formed hydrogen ions. The abnormal increase of Dy(3+) partitioning at 100 kGy is mainly attributed to the precipitation formed between Dy(3+) and radiolytic products (F(-) and SO3(2-)). PMID:24549120

  19. Polymer-supported ionic liquid solid phase extraction for trace inorganic and organic mercury determination in water samples by flow injection-cold vapor atomic absorption spectrometry.

    PubMed

    Escudero, Leticia B; Olsina, Roberto A; Wuilloud, Rodolfo G

    2013-11-15

    A simple and green technique named polymer-supported ionic liquid solid phase extraction (PSIL-SPE) was developed for mercury (Hg) species determination. Inorganic Hg (InHg) species was complexed with chloride ions followed by its introduction into a flow injection on-line system to quantitatively retain the anionic chlorocomplex (HgCl4(2-)) in a column packed with CYPHOS() IL 101-impregnated resin. The trapped InHg was then reduced with stannous chloride (SnCl2) and eluted with the same flow of reducing agent followed by cold vapor atomic absorption spectrometry (CV-AAS) detection. Organic mercury species (OrgHg) did not interact with the impregnated resin and were not retained into the column. Total concentration of OrgHg was evaluated by difference between total Hg and InHg concentration. A 95% extraction efficiency was achieved for InHg when the procedure was developed under optimal experimental conditions. The limit of detection obtained for preconcentration of 40 mL of sample was 2.4 ng L(-1) InHg. The relative standard deviation (RSD) was 2.7% (at 1 g L(-1) InHg and n=10) calculated from the peak height of absorbance signals (Gaussian-shape and reproducible peaks). This work reports the first polymer-supported IL solid phase extraction approach implemented in a flow injection on-line system for determination of Hg species in mineral, tap and river water samples. PMID:24148384

  20. Influence of Sulfur on the Carbon Deposition in Liquid Hydrocarbon Steam Reforming over CeO2-Al2O3 supported Ni and Rh Catalysts

    SciTech Connect

    C Xie; Y Chen; Y Li; X Wang; C Song

    2011-12-31

    This study was performed to elucidate the influence of sulfur on the carbon deposition in steam reforming of liquid hydrocarbons over CeO{sub 2}-Al{sub 2}O{sub 3} supported Ni and Rh catalysts at 800 C. The characteristics of the carbon deposits on the used catalysts after the reactions without and with sulfur were investigated by temperature-programmed oxidation (TPO), transmission electron microscopy (TEM), scanning transmission X-ray microscopy (STXM), temperature-programmed hydrogenation (TPH), X-ray absorption near edge structure (XANES), and scanning electron microscopy (SEM). Though abundant carbon deposits can accumulate on the pure CeO{sub 2}-Al{sub 2}O{sub 3} support due to fuel thermal cracking, the addition of Ni or Rh metal greatly reduced the carbon deposition in the sulfur-free reaction. The presence of sulfur increased the carbon deposition on both catalysts, which has a much more significant impact for the Ni catalyst. Carbon XANES study on the used catalysts revealed that graphitic carbon was dominant in the presence of sulfur, while oxidized carbon species (quinone-like carbon, carboxyl and carbonate) prevailed without sulfur. Meanwhile, the formation of carboxyl and carbonate more dramatically dropped on the Ni catalyst than that on the Rh catalyst. Our results strongly suggest that (I) the presence of sulfur can suppress carbon gasification and promote the formation of graphitic carbon on reforming catalysts due mainly to its poisoning effect on metals, and (II) Rh catalyst possesses stronger capability to maintain carbon gasification activity than Ni catalyst in the presence of sulfur.

  1. Determination of the triacylglycerol fraction in fish oil by comprehensive liquid chromatography techniques with the support of gas chromatography and mass spectrometry data.

    PubMed

    Beccaria, Marco; Costa, Rosaria; Sullini, Giuseppe; Grasso, Elisa; Cacciola, Francesco; Dugo, Paola; Mondello, Luigi

    2015-07-01

    Fish oil made from menhaden (Brevoortia tyrannus) can be used as a dietary supplement for the presence of high levels of the long-chained omega-3 fatty acids, viz. epentaenoic and docosahexanoic. In this work, for the first time, two different multidimensional approaches were developed and compared, in terms of peak capacity, for triacylglycerol characterization. In particular, silver ion chromatography with a silver-ion column and non-aqueous reverse-phase liquid chromatography with a C18 column were tested in both comprehensive (stop-flow) and off-line modes. The use of mass spectra attained by atmospheric pressure chemical ionization for both LC approaches, and the fatty acids methyl esters profile of menhaden oil obtained by gas chromatography analysis, greatly supported the elucidation of the triacylglycerol content in menhaden oil. The off-line approach afforded a better separation and, thus, higher peak capacity to allow identifying and semiquantifying more than 250 triacylglycerols. Such a huge number has never been reported for a menhaden oil sample.The main disadvantage of such an approach over the stop-flow one was the longer analysis time, mainly attributable to solvent exchange between the two dimensions. PMID:25963648

  2. Intra-batch effect correction in liquid chromatography-mass spectrometry using quality control samples and support vector regression (QC-SVRC).

    PubMed

    Kuligowski, Julia; Snchez-Illana, ngel; Sanjun-Herrez, Daniel; Vento, Mximo; Quints, Guillermo

    2015-11-21

    Instrumental developments in sensitivity and selectivity boost the application of liquid chromatography-mass spectrometry (LC-MS) in metabolomics. Gradual changes in the LC-MS instrumental response (i.e. intra-batch effect) are often unavoidable and they reduce the repeatability and reproducibility of the analysis, decrease the power to detect biological responses and hinder the interpretation of the information provided. Because of that, there is interest in the development of chemometric techniques for the post-acquisition correction of batch effects. In this work, the use of quality control (QC) samples and support vector regression (QC-SVRC) and a radial basis function kernel is proposed to correct intra-batch effects. The repeated analysis of a single sample is used for the assessment of both the correction accuracy and the effect of the distribution of QC samples throughout the batch. The QC-SVRC method is evaluated and compared with a recently developed method based on QC samples and robust cubic smoothing splines (QC-RSC). The results show that QC-SVRC slightly outperformed QC-RSC and allows a straightforward fitting of the SVRC parameters to the instrument performance by using the ?-insensitive loss parameter. PMID:26462549

  3. Visual test of subparts per billion-level mercuric ion with a gold nanoparticle probe after preconcentration by hollow fiber supported liquid membrane.

    PubMed

    Tan, Zhi-qiang; Liu, Jing-fu

    2010-05-15

    With the combination of the gold nanoparticle (AuNP)-based visual test with hollow fiber supported liquid membrane (HFSLM) extraction, a highly sensitive and selective method was developed for field detection of mercuric ion (Hg(2+)) in environmental waters. Hg(2+) in water samples was extracted through HFSLM and trapped in the aqueous acceptor and then visually detected based on the red-to-blue color change of 3-mercaptopropionic acid-functionalized AuNP (MPA-AuNP) probe. The highest extraction efficiency of Hg(2+) was obtained by using a 600 mL sample (pH 8.0, 2.0% (w/v) NaCl), approximately 35 microL of acceptor (10 mM of 2,6-pyridinedicarboxylic acid, pH 4.0) filled in the lumen of a polypropylene hollow fiber tubing (55 cm in length, 50 microm wall thickness, 280 microm inner diameter), a liquid membrane of 2.0% (w/v) trioctycphosphine oxide in undecane, and a shaking rate of 250 rpm. The chromegenic reaction was conducted by incubating the mixture of MPA-AuNP stock solution (12 microL, 15 nM), Tris-borate buffer solution (18 microL, 0.2 M, pH 9.5), and acceptor (30 microL) at 30 degrees C for 1 h. The detection limit can be adjusted to 0.8 microg/L Hg(2+) (corresponding to an enrichment factor of approximately 1000 in the HFSLM) and 2.0 microg/L Hg(2+) (the U.S. Environmental Protection Agency limit of [Hg(2+)] for drinkable water) by using extraction times of 3 and 1 h, respectively. The proposed method is extremely specific for Hg(2+) with tolerance to at least 1000-fold of other environmentally relevant heavy and transition metal ions and was successfully applied to detect Hg(2+) in a certified reference water sample, as well as real river, lake, and tap water samples. PMID:20405900

  4. A biological method of including mineralized human liquid and solid wastes into the mass exchange of bio-technical life support systems

    NASA Astrophysics Data System (ADS)

    Ushakova, S. A.; Tikhomirov, A. A.; Tikhomirova, N. A.; Kudenko, Yu. A.; Litovka, Yu. A.; Anishchenko, O. V.

    2012-10-01

    The main obstacle to using mineralized human solid and liquid wastes as a source of mineral elements for plants cultivated in bio-technical life support systems (BLSS) is that they contain NaCl. The purpose of this study is to determine whether mineralized human wastes can be used to prepare the nutrient solution for long-duration conveyor cultivation of uneven-aged wheat and Salicornia europaea L. plant community. Human solid and liquid wastes were mineralized by the method of "wet incineration" developed by Yu. Kudenko. They served as a basis for preparing the solutions that were used for conveyor-type cultivation of wheat community represented by 5 age groups, planted with a time interval of 14 days. Wheat was cultivated hydroponically on expanded clay particles. To reduce salt content of the nutrient solution, every two weeks, after wheat was harvested, 12 L of solution was removed from the wheat irrigation tank and used for Salicornia europaea cultivation in water culture in a conveyor mode. The Salicornia community was represented by 2 age groups, planted with a time interval of 14 days. As some portion of the nutrient solution used for wheat cultivation was regularly removed, sodium concentration in the wheat irrigation solution did not exceed 400 mg/L, and mineral elements contained in the removed portion were used for Salicornia cultivation. The experiment lasted 4 months. The total wheat biomass productivity averaged 30.1 g · m-2 · day-1, and the harvest index amounted to 36.8%. The average productivity of Salicornia edible biomass on a dry weight basis was 39.3 g · m-2 · day-1, and its aboveground mass contained at least 20% of NaCl. Thus, the proposed technology of cultivation of wheat and halophyte plant community enables using mineralized human wastes as a basis for preparing nutrient solutions and including NaCl in the mass exchange of the BLSS; moreover, humans are supplied with additional amounts of leafy vegetables.

  5. In silico and in vitro metabolism studies support identification of designer drugs in human urine by liquid chromatography/quadrupole-time-of-flight mass spectrometry.

    PubMed

    Tyrkk, Elli; Pelander, Anna; Ketola, Raimo A; Ojanper, Ilkka

    2013-08-01

    Human phase I metabolism of four designer drugs, 2-desoxypipradrol (2-DPMP), 3,4-dimethylmethcathinone (3,4-DMMC), ?-pyrrolidinovalerophenone (?-PVP), and methiopropamine (MPA), was studied using in silico and in vitro metabolite prediction. The metabolites were identified in drug abusers urine samples using liquid chromatography/quadrupole-time-of-flight mass spectrometry (LC/Q-TOF/MS). The aim of the study was to evaluate the ability of the in silico and in vitro methods to generate the main urinary metabolites found in vivo. Meteor 14.0.0 software (Lhasa Limited) was used for in silico metabolite prediction, and in vitro metabolites were produced in human liver microsomes (HLMs). 2-DPMP was metabolized by hydroxylation, dehydrogenation, and oxidation, resulting in six phase I metabolites. Six metabolites were identified for 3,4-DMMC formed via N-demethylation, reduction, hydroxylation, and oxidation reactions. ?-PVP was found to undergo reduction, hydroxylation, dehydrogenation, and oxidation reactions, as well as degradation of the pyrrolidine ring, and seven phase I metabolites were identified. For MPA, the nor-MPA metabolite was detected. Meteor software predicted the main human urinary phase I metabolites of 3,4-DMMC, ?-PVP, and MPA and two of the four main metabolites of 2-DPMP. It assisted in the identification of the previously unreported metabolic reactions for ?-PVP. Eight of the 12 most abundant in vivo phase I metabolites were detected in the in vitro HLM experiments. In vitro tests serve as material for exploitation of in silico data when an authentic urine sample is not available. In silico and in vitro designer drug metabolism studies with LC/Q-TOF/MS produced sufficient metabolic information to support identification of the parent compound in vivo. PMID:23797910

  6. Speciation Analysis of Labile and Total Silver(I) in Nanosilver Dispersions and Environmental Waters by Hollow Fiber Supported Liquid Membrane Extraction.

    PubMed

    Chao, Jing-Bo; Zhou, Xiao-Xia; Shen, Mo-Hai; Tan, Zhi-Qiang; Liu, Rui; Yu, Su-Juan; Wang, Xiao-Wei; Liu, Jing-Fu

    2015-12-15

    Hollow fiber supported liquid membrane (HFSLM) extraction was coupled with ICP-MS for speciation analysis of labile Ag(I) and total Ag(I) in dispersions of silver nanoparticles (AgNPs) and environmental waters. Ag(I) in aqueous samples was extracted into the HFSLM of 5%(m/v) tri-n-octylphosphine oxide in n-undecane, and stripped in the acceptor of 10 mM Na2S2O3 and 1 mM Cu(NO3)2 prepared in 5 mM NaH2PO4-Na2HPO4 buffer (pH 7.5). Negligible depletion and exhaustive extraction were conducted under static and 250 rpm shaking to extract the labile Ag(I) and total Ag(I), respectively. The extraction equilibration was reached in 8 h for both extraction modes. The extraction efficiency and detection limit were (2.97 0.25)% and 0.1 ?g/L for labile Ag(I), and (82.3 2.0)% and 0.5 ?g/L for total Ag(I) detection, respectively. The proposed method was applied to determine labile Ag(I) and total Ag(I) in different sized AgNP dispersions and real environmental waters, with spiked recoveries of total Ag(I) in the range of 74.0-98.1%. With the capability of distinguishing labile and total Ag(I), our method offers a new approach for evaluating the bioavailability and understanding the fate and toxicity of AgNPs in aquatic systems. PMID:26580982

  7. Development of liquid chromatographic method for the analysis of dabigatran etexilate mesilate and its ten impurities supported by quality-by-design methodology.

    PubMed

    Pantovi?, Jasmina; Malenovi?, An?elija; Vemi?, Ana; Kosti?, Na?a; Medenica, Mirjana

    2015-01-01

    In this paper, the development of reversed-phase liquid chromatographic method for the analysis of dabigatran etexilate mesilate and its ten impurities supported by quality by design (QbD) approach is presented. The defined analytical target profile (ATP) was the efficient baseline separation and the accurate determination of the investigated analytes. The selected critical quality attributes (CQAs) were the separation criterions between the critical peak pairs because the mixture complexity imposed a gradient elution mode. The critical process parameters (CPPs) studied in this research were acetonitrile content at the beginning of gradient program, acetonitrile content at the end of gradient program and the gradient time. Plan of experiments was defined by Box-Behnken design. The experimental domains of the three selected factors x1--content of the acetonitrile at the start of linear gradient, x2--content of the acetonitrile at the end of linear gradient and x3--gradient time (tG) were [10%, 30%], [48%, 60%] and [8 min, 15 min], respectively. In order to define the design space (DS) as a zone where the desired quality criteria is met providing also the quality assurance, Monte Carlo simulations were performed. The uniform error distribution equal to the calculated standard error was added to the model coefficient estimates. Monte Carlo simulation included 5000 iterations in each of 3969 defined grid points and the region having the probability ? ? 95% to achieve satisfactory values of all defined CQAs was computed. As a working point, following chromatographic conditions suited in the middle of the DS were chosen: 22% acetonitrile at the start of gradient program, 55.5% acetonitrile at the end of gradient program end and the gradient time of 11.5 min. The developed method was validated in order to prove its reliability. PMID:25828507

  8. Sensitivity enhancement in direct coupling of supported liquid membrane extractions to capillary electrophoresis by means of transient isotachophoresis and large electrokinetic injections.

    PubMed

    Pant??kov, Pavla; Kub?, Pavel; Bo?ek, Petr

    2015-04-10

    Enhanced sensitivity for determination of basic drugs in body fluids was achieved by in-line coupling of extraction across supported liquid membrane (SLM) to large electrokinetic injection and transient isotachophoresis-capillary zone electrophoresis (tITP-CZE) in commercial CZE instrument. Twelve cm long tITP plug of 300mM ammonium acetate was formed in the separation capillary just before the electrokinetic injection of acceptor solution containing nortriptyline, haloperidol and loperamide extracted across the SLM. The tITP plug ensured efficient stacking and preconcentration of the injected basic drugs due to the tITP action of ammonium and the drugs were then separated by CZE using 5.2M acetic acid as background electrolyte. No interferences were observed from highly-abundant body fluid species (NaCl and human serum albumin) due to the excellent clean-up properties of SLMs and analytical sensitivity increased up to 340 times compared to SLM extractions coupled in-line to CZE with standard hydrodynamic injections. The SLM-tITP-CZE method was characterized by good repeatability (RSDs of peak areas below 7.8%), linearity over two orders of magnitude (r(2) better than 0.994) and limits of detection (defined as 3S/N) between 3 and 45?g/L. Interfacing of SLM extractions to CZE instrumentation was achieved by low-cost, disposable micro-extraction devices, which can be routinely prepared in every analytical laboratory. These devices eliminated sample carry-over, minimized the need for manual sample handling and ensured fully automated determination (including extraction, injection, preconcentration and separation) of the three basic drugs in 20?L of untreated body fluids. PMID:25747667

  9. Halophytic plants as a component of a bioregenerative life support system for recycling of NaCl contained in human liquid waste.

    NASA Astrophysics Data System (ADS)

    Balnokin, Yurii; Balnokin, Yurii; Myasoedov, Nikolay; Popova, Larissa; Tikhomirov, Alexander A.; Ushakova, Sofya; Tikhomirova, Natalia; Lasseur, Christophe; Gros, Jean-Bernard

    Currently, the closure of matter turnover is one of the urgent problems of bioregenerative life support system (BLSS) designing. The important aspect of the problem is involving of substances contained in liquid and solid exometabolites of humans inhabiting BLSS into intrasystem matter turnover. Recycling of Na+ and Cl- contained in human liquid exometabolites, i.e. urine is acknowledged to be among the main tasks of the matter turnover in BLSS. The ions excreted with urine may be returned to human organism with food. A way to allow this is including edible halophytic plants into the phototrophic compartment of BLSS. Halophytes are defined as plants which can grow on saline soils and produce high biomass under these conditions. Some halophytes can take up high quantities of Na+ and Cl- and accumulate the ions in the shoots or extrude them to leaf surface by means of salt glands. To allow Na+ and Cl- recycling through halophyte utilization, the following principal steps should be accomplished: (i) mineralization of the exometabolites by physicochemical methods; (ii) oxidation of ammonia formed during the exometabolite mineralization to nitrate by nitrifying bacteria, (iii) growing the halophyte on the nutrient solution prepared on the basis of the mineralized exometabolites, (iv) introducing the halophyte green biomass into human food. The present work is devoted to the following problems: (i) selection of a salt-accumulating/extruding halophytic plant suitable for Na+ and Cl- recycling in BLSS and (ii) parameter evaluation of a plant conveyor containing the halophytic plants at various ages. Halophytic plants selected for BLSS should meet the following criteria: (i) ability to grow under 24-hour-illumination, (ii) high productivity, (iii) ability to accumulate Na+ and Cl- in high quantities in shoots or to excrete salts to leaf surface, (iv) edibility, and (v) high nutritive value of the biomass. Relying on these criteria, salt-accumulating halophyte Salicornia europaea was selected from seven halophytic plant candidates, preliminary chosen from observations in their natural habitats, from our previous investigations and literature data. Characterization of the plant performance was obtained in the experiments on plants grown in water culture in a cultivation chamber under controlled conditions. A model nutrient solution simulating mineralized urine was used for halophyte growing. Under the experimental conditions, S.europaea exhibited high productivity and accumulated Na+ and Cl- in the shoots in high quantities. It has been shown that above-ground organs of S.europaea exhibit high nutritive value, the proteins are enriched with the essential amino acids and displayed high abundance of leucine, aspartic and glutamic acids. The results demonstrate that it is feasible to put into practice permanent Na+ and Cl- recycling in BLSS by a various-aged S.europaea conveyor. Relying on data on distribution of Na+ and Cl- between the plant and growth medium, parameters of the conveyor for permanent ion turnover in the system humans - exometabolites - nutrient solution - S.europaea - humans have been evaluated.

  10. High-Surface-Area CO2 Sponge: High Performance CO2 Scrubbing Based on Hollow Fiber-Supported Designer Ionic Liquid Sponges

    SciTech Connect

    2010-09-01

    IMPACCT Project: The team from ORNL and Georgia Tech is developing a new technology that will act like a sponge, integrating a new, alcohol-based ionic liquid into hollow fibers (magnified image, right) to capture CO2 from the exhaust produced by coal-fired power plants. Ionic liquids, or salts that exist in liquid form, are promising materials for carbon capture and storage, but their tendency to thicken when combined with CO2 limits their efficiency and poses a challenge for their development as a cost-effective alternative to current-generation solutions. Adding alcohol to the mix limits this tendency to thicken in the presence of CO2 but can also make the liquid more likely to evaporate, which would add significantly to the cost of CO2 capture. To solve this problem, ORNL is developing new classes of ionic liquids with high capacity for absorbing CO2. ORNL’s sponge would reduce the cost associated with the energy that would need to be diverted from power plants to capture CO2 and release it for storage.

  11. Conveyor Cultivation of the Halophytic Plant Salicornia europaea for the Recycling of NaCl from Human Liquid Waste in a Biological Life Support System.

    NASA Astrophysics Data System (ADS)

    Balnokin, Yurii; Myasoedov, Nikolay; Popova, Larissa; Tikhomirov, Alexander A.; Ushakova, Sofya; Tikhomirova, Natalia; Lasseur, Christophe; Gros, Jean-Bernard

    One problem in designing bioregenerative life support systems (BLSS) is developing technolo-gies to include human liquid and solid waste in intrasystem recycling. A specific task is recycling of NaCl excreted in urine by humans. We showed recently that this could be achieved through inclusion of the salt accumulating halophyte Salicornia europaea in the autotrophic compart-ment of the BLSS (Balnokin et al., ASR, 2010, in press). A model of NaCl circulation in BLSS with inclusion of S. europaea was based on the NaCl turnover in the human -urine -nutrient solution -S. europaea -human cycle. Mineralized urine was used as a basis for preparation of a nutrient solution for the halophyte cultivation. The shoots of the halophyte cultivated in the mineralized urine and containing NaCl could to be used by the BLSS inhabitants in their diets. In this report we describe cultivation of S. europaea which allows turnover of NaCl and produces daily shoot biomass containing Na+ and Cl- in quantities approximately equal to those excreted in daily human urine. The plants were grown in water culture in a climatic chamber under controlled conditions. A solution simulating mineralized urine (SSMU) was used as a basis for preparation of a nutri-ent solution for S. europaea cultivation. For continuous biomass production, seedlings of S. europaea, germinated preliminary in moist sand, were being transferred to the nutrient solu-tion at regular intervals (every two days). Duration of the conveyor operation was 112 days. During the first 56 days, the seedlings were being planted in SSMU diluted by a factor of 1.5 (2/3 SSMU). The same solution was introduced into the growth vessels as volumes of growth medium decreased due to plant transpiration. Starting from the 56th day as conveyor operation was initiated, the plants were being harvested every two days; the solutions from the discharged vessels were mixed with the fresh SSMU and the mixture was introduced into all other growth vessels of the conveyor. Thus, during the first 56-d period, the plants grew only in the fresh nutrient solution, whereas during the second 56-d period, the worked out nutrient solutions were being returned into the cycle having been added to the growth vessels along with the fresh SSMU. Growth characteristics, water and ionic relations of S. europaea plants, balance of nutrients between organs and growth media for the first and second 56-d periods of the conveyor operation are presented. There was no significant difference in the rates of shoot biomass production during the first and the second periods. The plants were producing shoot biomass with the rates close to those observed under optimal conditions. However, substantial increase in root biomass production (by 50% on the dry mass basis) was observed in the second period as compared with the first one. Decrease in organ water contents on the dry mass basis (by 13% and 30% for shoots and roots, respectively) and transpiration rates (by 25%) occurred also in the second period as compared with the first one. Measurements of Na+ , Cl- and nutrient contents in the growth media and plant organs and calculation of their balances showed that the plants did not suffer from a deficiency of nutrients during the 112 days of the conveyor operation while accumulating required NaCl amounts. Observed root proliferation and deterioration of water relations in the second 56-d period of the conveyor operation may be caused by toxic plant metabolites exuded by roots into the growth medium.

  12. Evaluation of solid-supported room-temperature ionic liquids containing crown ethers as media for metal ion separation and preconcentration.

    PubMed

    Hawkins, Cory A; Momen, M A; Garvey, Sarah L; Kestell, John; Kaminski, Michael D; Dietz, Mark L

    2015-04-01

    Extraction chromatographic (EXC) resins incorporating an appropriate crown ether in an oxygenated organic solvent such as 1-octanol are well established as sorbents for the analytical-scale separation and preconcentration of radiostrontium from a variety of sample types. Recent solvent extraction studies employing crown ethers in various 1-alkyl-3-methylimidazolium-based (CnC1im(+)) room-temperature ionic liquids (RTILs) indicate that under certain conditions, distribution ratios (DSr) for strontium far in excess of those observed with conventional organic solvents are observed. To determine if this increase in liquid-liquid extraction efficiency will lead to improved strontium sorbents, several EXC resins and sol-gel glasses incorporating di-tert-butylcyclohexano-18-crown-6 (DtBuCH18C6) in either 1-decyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide (C10C1imTf2N) or the related hydroxyalkyl-functionalized IL 1-(12-hydroxydodecyl)-3-butylimidazolium bis[(trifluoromethyl)sulfonyl]imide (C12OHC4im Tf2N) were prepared and characterized. Unexpectedly the performance of these materials was not uniformly better than that of a conventional EXC resin, an apparent result of the greater viscosity of the ionic liquids and the lower solubility of the crown ether in ILs versus conventional organic solvents. PMID:25640134

  13. Liquid-phase methanol process development unit: installation, operation, and support studies. Technical progress report No. 1, 28 September 1981-31 December 1981

    SciTech Connect

    Not Available

    1982-01-20

    During this period the Work Breakdown Structure Dictionary was established. Task 1 was completed with submittal of the Project Work Plan and the Quality Assurance Manual. CSI produced basic process design information and a preliminary flowsheet for the LaPorte LPMeOH PDU. APCI developed the flowsheet further and set up the process on APCI's process simulator. The flowsheet development revealed a number of major changes necessary in the existing LPM pilot plant; this has led to pursuit of a unified design concept. Approval was requested for the unified design concept as well as advanced schedule for relocation of the LPM unit and advanced procurement of long delivery equipment items. A number of preliminary heat and material balances were calculated for the LPMeOH PDU and preliminary process specifications were prepared for the equipment items. The final design basis was established. The design pressure was set at 1000 psig. Eight design operating cases were defined for the following range of reactor operating conditions: Pressure - 500 to 900 psig, Temperature - 220 to 270/sup 0/C, Liquid-Fluidized Space Velocity - 1000 to 4000 l/hr-kg catalyst, Liquid-Entrained Space Velocity - 2000 to 10,000 l/hr-kg catalyst, and Liquid-Entrained Catalyst Loading - 0.1 to 0.4 kg catalyst/l oil. The methanol production rate for these cases ranges from 0.2 to 9.7 short tons per day. Preliminary equipment arrangement and site layout drawings were prepared for the PDU. In the laboratories, CSI began autoclave testing of in-situ catalyst reduction procedures. The specification and evaluation of equipment for the CSI laboratory PDU progressed. CSI prepared and issued a Topical Report covering liquid-entrained LPMeOH lab development work accomplished under advance funding. APCI's laboratories progressed with the design of the bench scale slurry reactor.

  14. Experimental data and analysis to support the design of an ion-exchange process for the treatment of Hanford tank waste supernatant liquids

    SciTech Connect

    Kurath, D.E.; Bray, L.A.; Brooks, K.P.; Brown, G.N.; Bryan, S.A.; Carlson, C.D.; Carson, K.J.; DesChane, J.R.; Elovich, R.J.; Kim, A.Y.

    1994-12-01

    Hanford`s 177 underground storage tanks contain a mixture of sludge, salt cake, and alkaline supernatant liquids. Disposal options for these wastes are high-level waste (HLW) glass for disposal in a repository or low-level waste (LLW) glass for onsite disposal. Systems-engineering studies show that economic and environmental considerations preclude disposal of these wastes without further treatment. Difficulties inherent in transportation and disposal of relatively large volumes of HLW make it impossible to vitrify all of the tank waste as HLW. Potential environmental impacts make direct disposal of all of the tank waste as LLW glass unacceptable. Although the pretreatment and disposal requirements are still being defined, most pretreatment scenarios include retrieval of the aqueous liquids, dissolution of the salt cakes, and washing of the sludges to remove soluble components. Most of the cesium is expected to be in the aqueous liquids, which are the focus of this report on cesium removal by ion exchange. The main objectives of the ion-exchange process are removing cesium from the bulk of the tank waste (i.e., decontamination) and concentrating the separated cesium for vitrification. Because exact requirements for removal of {sup 137}Cs have not yet been defined, a range of removal requirements will be considered. This study addresses requirements to achieve {sup 137}Cs levels in LLW glass between (1) the Nuclear Regulatory Commission (NRC) Class C (10 CFR 61) limit of 4600 Ci/m{sup 3} and (2) 1/10th of the NRC Class A limit of 1 Ci/m{sup 3} i.e., 0.1/m{sup 3}. The required degrees of separation of cesium from other waste components is a complex function involving interactions between the design of the vitrification process, waste form considerations, and other HLW stream components that are to be vitrified.

  15. Characterization of an internal-surface reversed-phase silica support for liquid chromatography and its application to assays of drugs in serum.

    PubMed

    Haginaka, J; Wakai, J; Yasuda, N; Yasuda, H; Kimura, Y

    1990-08-31

    Internal-surface reversed-phase (ISRP) silica supports having N-octanoylaminopropyl phases bound to the internal surfaces of the porous silica and N-(2,3-dihydroxypropyl)aminopropyl phases bound to the external surfaces were synthesized from silica particles differing in nominal pore diameters and specific surface areas. These ISRP supports were characterized with regard to physical and chromatographic properties. The support with an N-octanoylaminopropyl phase coverage of 485 mumol/g and an average pore diameter of 65 A was the most suitable for the direct-injection determination of hydrophilic or hydrophobic drugs in serum or plasma. Non-steroidal anti-inflammatory (acetylsalicylic acid and salicylic acid) and tricyclic antidepressant drugs (desipramine and nortriptyline) in serum were successfully determined with this support and an acidic eluent. PMID:2178170

  16. Ionic liquid supported on an electrodeposited polycarbazole film for the headspace solid-phase microextraction and gas chromatography determination of aromatic esters.

    PubMed

    Feng, Yuanyuan; Zhao, Faqiong; Zeng, Baizhao

    2015-05-01

    A polycarbazole film was electrodeposited on a stainless-steel wire from a solution of N,N-dimethylformamide/propylene carbonate (1:9 v/v) containing 0.10 M carbazole and 0.10 M tetrabutylammonium perchlorate. The obtained polycarbazole fiber was immersed into an ionic liquid (1-hydroxyethyl-3-methyl imidazolium bis[(trifluoromethyl)sulfonyl]imide) solution (in dimethylsulfoxide) for 30 min, followed by drying under an infrared lamp. The resulting polycarbazole/ionic liquid fiber was applied to the headspace solid-phase microextraction and determination of aromatic esters by coupling with gas chromatography and flame ionization detection. Under the optimized conditions, the limits of detection were below 61 ng/L (S/N = 3) and the linear ranges were 0.061-500 μg/L with correlation coefficients above 0.9876. The relative standard deviations were below 4.8% (n = 5) for a single fiber, and below 9.9% for multi-fiber (n = 4). This fiber also exhibited good stability. It could be used for more than 160 times of headspace solid-phase microextraction and could withstand a high temperature up to 350°C. PMID:25676087

  17. An Improved Method for the Separation of Lead-210 from Ra-DEF for Radioactive Equilibrium Experiments: Microscale Liquid-Liquid Extraction Using a Polymer-Supported Crown Ether

    NASA Astrophysics Data System (ADS)

    Dietz, Mark L.; Horwitz, E. Philip

    1996-02-01

    A novel extraction chromatographic material, comprised of a solution of a lead-selective macrocyclic polyether (di-t-butylcyclohexano-18-crown-6) in isodecanol sorbed on an inert polymeric support, is shown to provide a rapid and simple means for the separation of lead-210 from its daughter products for subsequent radiochemical experimentation.

  18. HANFORD DOUBLE SHELL TANK (DST) THERMAL & SEISMIC PROJECT SEISMIC ANALYSIS IN SUPPORT OF INCREASED LIQUID LEVEL IN 241-AP TANK FARMS

    SciTech Connect

    MACKEY TC; ABBOTT FG; CARPENTER BG; RINKER MW

    2007-02-16

    The overall scope of the project is to complete an up-to-date comprehensive analysis of record of the DST System at Hanford. The "Double-Shell Tank (DST) Integrity Project - DST Thermal and Seismic Project" is in support of Tri-Party Agreement Milestone M-48-14.

  19. A high-performance liquid chromatography-based assay of glutathione transferase omega 1 supported by glutathione or non-physiological reductants.

    PubMed

    Nmeti, Balzs; Por, Mikls; Gregus, Zoltn

    2015-01-15

    The unusual glutathione S-transferase GSTO1 reduces, rather than conjugates, endo- and xenobiotics, and its role in diverse cellular processes has been proposed. GSTO1 has been assayed spectrophotometrically by measuring the disappearance of its substrate, S-(4-nitrophenacyl)glutathione (4-NPG), in the presence of 2-mercaptoethanol that regenerates GSTO1 from its mixed disulfide. To assay GSTO1 in rat liver cytosol, we have developed a high-performance liquid chromatography (HPLC)-based procedure with two main advantages: (i) it measures the formation of the 4-NPG reduction product 4-nitroacetophenone, thereby offering improved sensitivity and accuracy, and (ii) it can use glutathione, the physiological reductant of GSTO1, which is impossible to do with the spectrophotometric procedure. Using the new assay, we show that (i) the GSTO1-catalyzed reduction of 4-NPG in rat liver cytosol also yields 1-(4-nitrophenyl)ethanol, whose formation from 4-nitroacetophenone requires NAD(P)H; (ii) the two assays measure comparable activities with 2-mercaptoethanol or tris(2-carboxyethyl)phosphine used as reductant; (iii) the cytosolic reduction of 4-NPG is inhibited by GSTO1 inhibitors (KT53, 5-chloromethylfluorescein diacetate, and zinc), although the inhibitory effect is strikingly influenced by the type of reductant in the assay and by the sequence of reductant and inhibitor addition. Characterization of GSTO1 inhibitors with the improved assay provides better understanding of interaction of these chemicals with the enzyme. PMID:25283130

  20. Liquid phase methanol LaPorte process development unit: Modification operation, and support studies. Task 3.6/3.7: Alternative catalyst/life run

    SciTech Connect

    Not Available

    1991-01-28

    In April 1987, Air Products started the third and final contract with the US Department of Energy to develop the Liquid Phase Methanol (LPMEOH) process. One of the objectives was to identify alternative commercial catalyst(s) for the process. This objective was strategically important as we want to demonstrate that the LPMEOH process is flexible and not catalyst selection limited. Among three commercially available catalysts evaluated in the lab, the catalyst with a designation of F21/0E75-43 was the most promising candidate. The initial judging criteria included not only the intrinsic catalyst activity but also the ability to be used effectively in a slurry reactor. The catalyst was then advanced for a 40-day life test in a laboratory 300 cc autoclave. The life test result also revealed superior stability when compared with that of a standard catalyst. Consequently, the new catalyst was recommended for demonstration in the Process Development Unit (PDU) at LaPorte, Texas. This report details the methodology of testing and selecting the catalyst.

  1. Reaction profiling by ultra high-pressure liquid chromatography/time-of-flight mass spectrometry in support of the synthesis of DNA-encoded libraries.

    PubMed

    Hargiss, Leonard O; Zipp, G Greg; Jessop, Theodore C; Sun, Xuejun; Keyes, Philip; Rawlins, David B; Liang, Zhi; Park, Kum Joo; Gu, Huizhong

    2014-11-15

    An ultra high-pressure liquid chromatography/mass spectrometry (UHPLC/MS) separation and analysis method has been devised for open access analysis of synthetic reactions used in the production of DNA-encoded chemical libraries. The aqueous mobile phase is 100mM hexafluoroisopropanol and 8.6mM triethylamine; the organic mobile phase is methanol. The UHPLC separation uses a C18 OST column (50mm2.1mm1.7?m) at 60C, with a flow rate of 0.6mL/min. Gradient concentration is from 10 to 40% B in 1.0min, increasing to 95% B at 1.2min. Cycle time was about 5min. This method provides a detection limit of a 20-mer oligonucleotide by mass spectrometry of better than 1pmol on-column. Linear UV response for 20-mer extends from 2 to 200pmol/?L in concentration, same-day relative average deviations are less than 5% and bias (observed minus expected) is less than 10%. Deconvoluted mass spectra are generated for components in the predicted mass range using a maximum entropy algorithm. Mass accuracy of deconvoluted spectra is typically 20ppm or better for isotopomers of oligonucleotides up to 7000Da. PMID:25282130

  2. Development of hollow fiber-supported liquid-phase microextraction and HPLC-DAD method for the determination of pyrethroid metabolites in human and rat urine.

    PubMed

    Bartosz, Wielgomas; Marcin, Wi?niewski; Wojciech, Czarnowski

    2014-05-01

    A simple hollow fiber liquid-phase microextraction method for the determination of synthetic pyrethroid metabolites, 3-phenoxybenzoic acid and 4-hydroxy-3-phenoxybenzoic acid, in human and rat urine was developed and validated. A polypropylene hollow fiber tightly fitted onto a Nylon rod and impregnated with organic solvent served as a disposable extraction device. Desorption of analytes was carried out in NaOH solution, analyzed further by gradient HPLC and diode array detection method. Important factors were identified using Taguchi OA16 (4(5) ) orthogonal array design and further optimized using univariate approach. The optimum method performance was observed when 1?mL of urine hydrolyzed with 0.2?mL of concentrated HCl was further supplemented with 100?mg of NaCl and extracted for 120?min into dihexyl ether immobilized in the pores of the hollow fiber. Metabolites were desorbed into 0.1?mL of 0.1?M NaOH for another 120?min. Limits of detection and quantitation of 15 and 50?ng/mL were obtained for both analytes. Relative standard deviations of 1.6-12.6% over the linear range (50-10,000?ng/mL, r?>?0.9906) were observed. Intra- and inter-day accuracies of the method ranged from 98.3 to 109.5% and from 93.3 to 110.9%, respectively. The optimized method was applied to the analysis of real urine samples collected from rats exposed orally to cypermethrin. PMID:24347457

  3. Evaluation of the measurement of Cu(II) bioavailability in complex aqueous media using a hollow-fiber supported liquid membrane device (HFSLM) and two microalgae species (Pseudokirchneriella subcapitata and Scenedesmus acutus).

    PubMed

    Rodrguez-Morales, Erik A; Rodrguez de San Miguel, Eduardo; de Gyves, Josefina

    2015-11-01

    The environmental bioavailability of copper was determined using a hollow-fiber supported liquid membrane (HFSLM) device as a chemical surrogate and two microalgae species (Scenedesmus acutus and Pseudokirchneriella subcapitata). Several experimental conditions were studied: pH, the presence of organic matter, inorganic anions, and concomitant cations. The results indicated a strong relationship between the response given by the HFSLM and the microalgae species with free copper concentrations measured by an ion selective electrode (ISE), in accordance with the free-ion activity model (FIAM). A significant positive correlation was evident when comparing the bioavailability results measured by the HFSLM and the S. acutus microalga species, showing that the synthetic device may emulate biological uptake and, consequently, be used as a chemical test for bioavailability measurements using this alga as a biological reference. PMID:26431807

  4. Liquid metal pump

    SciTech Connect

    Pennell, W.E.

    1982-11-23

    The liquid metal pump comprises floating seal rings and attachment of the pump diffuser to the pump bowl for isolating structural deflections from the pump shaft bearings. The seal rings also eliminate precision machining on large assemblies by eliminating the need for a close tolerance fit between the mounting surfaces of the pump and the seals. The liquid metal pump also comprises a shaft support structure that is isolated from the pump housing for better preservation of alignment of shaft bearings. The shaft support structure also allows for complete removal of pump internals for inspection and repair.

  5. Liquid metal pump

    DOEpatents

    Pennell, William E. (Greensburg, PA)

    1982-01-01

    The liquid metal pump comprises floating seal rings and attachment of the pump diffuser to the pump bowl for isolating structural deflections from the pump shaft bearings. The seal rings also eliminate precision machining on large assemblies by eliminating the need for a close tolerance fit between the mounting surfaces of the pump and the seals. The liquid metal pump also comprises a shaft support structure that is isolated from the pump housing for better preservation of alignment of shaft bearings. The shaft support structure also allows for complete removal of pump internals for inspection and repair.

  6. Preconcentration of emerging contaminants in environmental water samples by using silica supported Fe3O4 magnetic nanoparticles for improving mass detection in capillary liquid chromatography.

    PubMed

    Moliner-Martnez, Yolanda; Ribera, Antonio; Coronado, Eugenio; Campns-Falc, P

    2011-04-22

    A magnetic material based on Fe(3)O(4) magnetic nanoparticles incorporated in a silica matrix by using a sol-gel procedure has been used to extract and preconcentrate emerging contaminants such as acetylsalicylic acid, acetaminophen, diclofenac and ibuprofen from environmental water samples prior to the analysis with Capillary LC-MS. The use of the proposed silica supported Fe(3)O(4) magnetic nanoparticles enables surfactant free extracts for the analysis with MS detection without interferences in the ionisation step. Under the optimum conditions, we demonstrated the reusability of the magnetic sorbent material during 20 uses without loss in the extraction efficiency. In addition, no cleanup was necessary. The preconcentration factor was 100 and the detection limits were between 50 and 150 ng/L. The proposed procedure has been applied to the analysis of water samples obtaining recoveries between 80 and 110% and RSD values lower than 12%. Concentrations of the target analytes over the range 1.7 and 0.1 ?g/L have been found in different water samples. PMID:21388625

  7. Assessing the feasibility of involving gaseous products resulting from physicochemical oxidation of human liquid and solid wastes in the cycling of a bio-technical life support system

    NASA Astrophysics Data System (ADS)

    Tikhomirov, Alexander; Kudenko, Yurii; Trifonov, Sergey; Ushakova, Sofya

    2012-01-01

    The study addresses the possible ways of involving gaseous products produced by "wet" incineration of human wastes mixed with H2O2 in an alternating electric field in the cycling of the physical model of a bio-technical life support system (BTLSS). The resulting gas mixture contains CO2 and O2, which are easily involved in the cycling in the closed ecosystem, and NH3, which is unacceptable in the atmosphere of the BTLSS. NH3 fixation has been proposed, which is followed by nitrification and involvement of the resulting products in the mass exchange of the closed system. Experiments have been performed to show that plants can be grown in the atmosphere resulting from the closing of the gas loop that includes a physicochemical installation and a growth chamber with plants representing the phototrophic compartment of the BTLSS. The results of the study suggest the conclusion that the proposed method of organic waste oxidation can be a useful tool in creating a physical model of a closed-loop integrated BTLSS.

  8. Recent development of ionic liquid stationary phases for liquid chromatography.

    PubMed

    Shi, Xianzhe; Qiao, Lizhen; Xu, Guowang

    2015-11-13

    Based on their particular physicochemical characteristics, ionic liquids have been widely applied in many fields of analytical chemistry. Many types of ionic liquids were immobilized on a support like silica or monolith as stationary phases for liquid chromatography. Moreover, different approaches were developed to bond covalently ionic liquids onto the supporting materials. The obtained ionic liquid stationary phases show multi-mode mechanism including hydrophobic, hydrophilic, hydrogen bond, anion exchange, π-π, and dipole-dipole interactions. Therefore, they could be used in different chromatographic modes including ion-exchange, RPLC, NPLC and HILIC to separate various classes of compounds. This review mainly summarizes the immobilized patterns and types of ionic liquid stationary phases, their retention mechanisms and applications in the recent five years. PMID:26463427

  9. Liquid Metals

    NASA Astrophysics Data System (ADS)

    March, Norman Henry

    1990-10-01

    This comprehensive, research level introduction to the theory of liquid metals presents the concepts needed to understand the properties of these metals starting with a survey of the basic experimental facts. The quantitative theory of liquid pair correlation functions, effective ion-ion interactions, thermodynamic properties and electronic and atomic transport is then developed. The book also explores inelastic neutron scattering from bulk liquid metals, critical behavior, magnetism, the present understanding of the liquid metal surface, binary liquid metals, shock wave studies, liquid hydrogen plasmas and the constitution of red star giants. This is an informative text for advanced postgraduate students and researchers in condensed matter physics, theoretical physics, physical chemistry and theoretical chemistry.

  10. Efficient transport of Am(III) from nitric acid medium using a new conformationally constrained (N,N,N',N'-tetra-2-ethylhexyl)7-oxabicyclo[2.2.1]heptane-2,3-dicarboxamide across a supported liquid membrane.

    PubMed

    Sharma, S; Panja, S; Ghosh, S K; Dhami, P S; Gandhi, P M

    2016-03-15

    Am(III) is one of the most hazardous radionuclide present in nuclear fuel cycle. A new conformationally constrained diamide, (N,N,N',N'-tetra-2-ethylhexyl)7-oxabicyclo[2.2.1]heptane-2,3-dicarboxamide (OBDA) was studied for Am(III) transport from HNO3 medium across a Supported Liquid Membrane. Transport rate was observed to be significantly fast with ?95% transport of Am(III) within 1h using 0.1M OBDA in the presence of 15% isodecyl alcohol (IDA)/n-dodecane as carrier. The mechanism of transport was investigated by studying various parameters like feed HNO3/NaNO3 concentration, OBDA concentration in the membrane, membrane pore size, membrane thickness etc. From these studies, the mechanism of transport was found to be diffusion controlled with diffusion co-efficient value of 5.110(-6)cm(2)/s. The membrane was found to be highly selective for tri- and tetra-valent actinides, and trivalent lanthanides. OBDA based membrane was found to be stable for at least for ten consecutive cycles of operation. PMID:26685064

  11. Tube support

    DOEpatents

    Mullinax, Jerry L. (Green Township, Summit County, OH)

    1988-01-01

    A tube support for supporting horizontal tubes from an inclined vertical support tube passing between the horizontal tubes. A support button is welded to the vertical support tube. Two clamping bars or plates, the lower edges of one bearing on the support button, are removably bolted to the inclined vertical tube. The clamping bars provide upper and lower surface support for the horizontal tubes.

  12. Sulfur poisoning of CeO[subscript 2]-Al[subscript 2]O[subscript 3]-supported mono- and bi-metallic Ni and Rh catalysts in steam reforming of liquid hydrocarbons at low and high temperatures

    SciTech Connect

    Xie, Chao; Chen, Yongsheng; Li, Yan; Wang, Xiaoxing; Song, Chunshan

    2010-12-01

    In order to develop a better understanding on sulfur poisoning of reforming catalysts in fuel processing for hydrogen production, steam reforming of liquid hydrocarbons was performed over CeO{sub 2}-Al{sub 2}O{sub 3} supported monometallic Ni and Rh and bimetallic Rh-Ni catalysts at 550 and 800 C. XANES was used to identify the sulfur species in the used catalysts and to study their impacts on the metal surface properties probed by XPS. It was found that both monometallic catalysts rapidly deactivated at 550 C, and showed poor sulfur tolerance. Although ineffective for the Ni catalyst, increasing the temperature to 800 C dramatically improved the sulfur tolerance of the Rh catalyst. XANES revealed that metal sulfide and organic sulfide are the dominant sulfur species on the used Ni catalyst, while sulfonate and sulfate predominate on the used Rh catalyst. The presence of sulfur induced severe carbon deposition on the Ni catalyst at 800 C. The superior sulfur tolerance of the Rh catalyst at 800 C may be associated with its capability in sulfur oxidation. It is likely that the formation of the oxygen-shielded sulfur structure of sulfonate and sulfate can suppress the poisoning impact of sulfur on Rh by inhibiting direct rhodium-sulfur interaction. Moreover, XPS indicated that the metal surface properties of the Rh catalysts after the reaction without and with sulfur at 800 C are similar, suggesting that sulfur poisoning on Rh was mitigated under the high-temperature condition. Although the Rh-Ni catalyst exhibited better sulfur tolerance than the monometallic catalysts at 550 C, its catalytic performance was inferior compared with the Rh catalyst in the sulfur-containing reaction at 800 C probably due to the severe carbon deposition on the bimetallic catalyst.

  13. Liquid Bridge

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Crystal Growth in magnetic fields, a float-zone sample, the surface tension of the melt keeps the sample suspended between the sample rods in the furnace forming an actual liquid bridge. Principal Investigator: Dr. Frank Szofran

  14. PREFACE: Functionalized Liquid Liquid Interfaces

    NASA Astrophysics Data System (ADS)

    Girault, Hubert; Kornyshev, Alexei A.; Monroe, Charles W.; Urbakh, Michael

    2007-09-01

    Most natural processes take place at interfaces. For this reason, surface science has been a focal point of modern research. At solid-liquid interfaces one can induce various species to adsorb or react, and thus may study interactions between the substrate and adsorbates, kinetic processes, optical properties, etc. Liquid-liquid interfaces, formed by immiscible liquids such as water and oil, have a number of distinctive features. Both sides of the interface are amenable to detailed physical and chemical analysis. By chemical or electrochemical means, metal or semiconductor nanoparticles can be formed or localised at the interface. Surfactants can be used to tailor surface properties, and also to place organic molecular or supermolecular constructions at the boundary between the liquids. Electric fields can be used to drive ions from one fluid to another, or even change the shape of the interface itself. In many cases, both liquids are optically transparent, making functionalized liquid-liquid interfaces promising for various optical applications based on the transmission or reflection of light. An advantage common to most of these systems is self-assembly; because a liquid-liquid interface is not mechanically constrained like a solid-liquid interface, it can easily access its most stable state, even after it has been driven far from equilibrium. This special issue focuses on four modes of liquid-liquid interfacial functionalization: the controlled adsorption of molecules or nanoparticles, the formation of adlayers or films, electrowetting, and ion transfer or interface-localized reactions. Interfacial adsorption can be driven electrically, chemically, or mechanically. The liquid-liquid interface can be used to study how anisotropic particles orient at a surface under the influence of a field, how surfactants interact with other adsorbates, and how nanoparticles aggregate; the transparency of the interface also makes the chirality of organic adsorbates amenable to optical study. Film formation goes a step beyond adsorption; some surfactants form monolayers or multilayers at the interface. A polymer microfilm or a polymer-particle matrix can be synthesized at the liquid-liquid boundary. Such films exhibit unique adsorption and ion-intercalation properties of their own. Electrowetting refers broadly to the phenomenon in which an applied voltage modulates the shape of a liquid-liquid interface, essentially by altering the surface tension. Electric fields can be used to induce droplets on solid substrates to change shape, or to affect the structure of liquid-liquid emulsions. Various chemical reactions can be performed at the liquid-liquid boundary. Liquid-liquid microelectrodes allow detailed study of ion-transfer kinetics at the interface. Photochemical processes can also be used to control the conformations of molecules adsorbed at the interface. But how much precise control do we actually have on the state of the interfacial region? Several contributions to this issue address a system which has been studied for decades in electrochemistry, but remains essentially unfamilar to physicists. This is the interface between two immiscible electrolytic solutions (ITIES), a progressing interdisciplinary field in which condensed-matter physics and physical chemistry meet molecular electrochemistry. Why is it so exciting? The reason is simple. The ITIES is chargeable: when positioned between two electrodes it can be polarized, and back- to-back electrical double layers form on both sides of the liquid-liquid interface. Importantly, the term immiscible refers not only to oil and water but also to the electrolytes. Inorganic electrolytes, such as alkali halides, tend to stay in water, whereas organic electrolytes, such as tetrabutylammonium tetraphenylborate, stay in oil. This behaviour arises because energies of the order of 0.2-0.3 eV are needed to drive ions across the interface. As long as these free energies of transfer are not exceeded by the external potential bias, the ITIES works as an 'electrode'; there is no traffic of ions across it. Thus the interface can sustain fields of the order of 106 V/cm, which are localized in a nanoscopic layer near the interface. This gives many new options for building various kinds of electrically tunable self assembled moloecular devices. Through the years, ITIES have been considered by electrochemists as a popular biomimetic model system, or for studies of interfacial reaction kinetics; ITIES were also used in industrial phase-transfer catalysis. Recently, this system has opened up new options for nano-scale engineering of functional assemblies (for dense information storage, efficient energy conversion, light-harvesting, and miniaturized sensors), which justifies its presentation in this issue.

  15. Antiferromagnetic marginal Fermi liquid

    SciTech Connect

    Zimanyi, G.T. ); Bedell, K.S. )

    1993-09-01

    The infrared singularities of the marginal-Fermi-liquid theory are treated within a perturbative renormalization-group approach for the original, weakly-momentum-dependent model. Then an alternative framework is introduced: marginal Fermi liquids with strong antiferromagnetic fluctuations. The models in both cases are found to be stable in a limited range of parameters, otherwise non-Fermi-liquid behavior is obtained. Comparison with experiments on the conductivity and spin susceptibility yields quite reasonable agreement between theory and the data in the case of the antiferromagnetic formulation. Trends with the doping and differences between copper and oxygen relaxation rates also gain a natural explanation. Analogies with the Luttinger-liquid ideas are also explored. Finally the antiferromagnetic marginal Fermi liquid offers clues about the microscopic origin of the anomalous fluctuations as well, as we find that the antiferromagnetic model is the [ital minimal] [ital model] capable of supporting a fixed line of the scaling equations, making it a promising candidate for the microscopic foundation of high-temperature superconductivity.

  16. Liquid phase methanol LaPorte Process Development Unit: Modification, operation, and support studies. Task 2.2: Process variable Scan Run E-8 and in-situ activation with syngas Run E-9

    SciTech Connect

    Not Available

    1991-02-28

    The LPMEOH process was conceived and patented by Chem Systems Inc. in 1975. Initial research and studies on the process focused on two distinct modes of operation. The first was a liquid fluidized mode with relatively large catalyst pellets suspended in a fluidizing liquid, and the second was an entrained (slurry) mode with fine catalyst particles slurried in an inert liquid. The development of both operating modes progressed in parallel from bench scale reactors, through an intermediate scale lab PDU, and then to the LaPorte PDU in 1984. The slurry mode of operation was ultimately chosen as the operating mode of choice due to its superior performance.

  17. Liquid Crystals

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Thermochromic liquid crystals, or TLCs, are a type of liquid crystals that react to changes in temperature by changing color. The Hallcrest/NASA collaboration involved development of a new way to visualize boundary layer transition in flight and in wind tunnel testing of aircraft wing and body surfaces. TLCs offered a new and potentially better method of visualizing the boundary layer transition in flight. Hallcrest provided a liquid crystal formulation technique that afforded great control over the sensitivity of the liquid crystals to varying conditions. Method is of great use to industry, government and universities for aerodynamic and hydrodynamic testing. Company's principal line is temperature indicating devices for industrial use, such as non-destructive testing and flaw detection in electric/electronic systems, medical application, such as diagnostic systems, for retail sale, such as room, refrigerator, baby bath and aquarium thermometers, and for advertising and promotion specials. Additionally, Hallcrest manufactures TLC mixtures for cosmetic applications, and liquid crystal battery tester for Duracell batteries.

  18. A New Class of Ionic Liquids: Anion Amphiprotic Ionic Liquids.

    PubMed

    Treskow, Marcel; Pitawala, Jagath; Arenz, Sven; Matic, Aleksandar; Johansson, Patrik

    2012-08-16

    We here present a new class of protic ionic liquids, anion amphiprotic ionic liquids (AAILs). These materials are protonation equilibrium free protic ionic liquids and interesting in their own right by not following the classical Brnsted acid-base neutralization concept. Due to the very simple synthesis route applied and their stable basic chemistry, we believe in a potential use for manifold applications. This is supported by the combination of practical material properties, foremost, a general intrinsic stability versus reversal of the formation reaction toward neutral species, broad liquidus ranges, long-term thermal stabilities, high conductivities, protic characteristics, and a general stability versus water. PMID:26295756

  19. Method for treating liquid wastes

    DOEpatents

    Katti, K.V.; Volkert, W.A.; Singh, P.; Ketring, A.R.

    1995-12-26

    The method of treating liquid waste in a media is accomplished by exposing the media to phosphinimines and sequestering {sup 99}Tc from the media by the phosphinimine (PN) functionalities. The system for treating the liquid waste in the media includes extraction of {sup 99}TcO{sub 4}{sup {minus}} from aqueous solutions into organic solvents or mixed organic/polar media, extraction of {sup 99}Tc from solutions on a solid matrix by using a container containing PN functionalities on solid matrices including an inlet and outlet for allowing flow of media through an immobilized phosphinimine ligand system contained within the container. Also, insoluble suspensions of phosphinimine functionalities on solid matrices in liquid solutions or present on supported liquid membranes (SLM) can be used to sequester {sup 99}Tc from those liquids. 6 figs.

  20. Method for treating liquid wastes

    DOEpatents

    Katti, Kattesh V. (Columbia, MO); Volkert, Wynn A. (Columbia, MO); Singh, Prahlad (Columbia, MO); Ketring, Alan R. (Columbia, MO)

    1995-01-01

    The method of treating liquid waste in a media is accomplished by exposing the media to phosphinimines and sequestering .sup.99 Tc from the media by the phosphinimine (PN) functionalities. The system for treating the liquid waste in the media includes extraction of .sup.99 TcO.sub.4.sup.- from aqueous solutions into organic solvents or mixed organic/polar media, extraction of .sup.99 Tc from solutions on a solid matrix by using a container containing PN functionalities on solid matrices including an inlet and outlet for allowing flow of media through an immobilized phosphinimine ligand system contained within the container. Also, insoluble suspensions of phosphinimine functionalities on solid matrices in liquid solutions or present on supported liquid membranes (SLM) can be used to sequester .sup.99 Tc from those liquids.

  1. Steam generator support system

    DOEpatents

    Moldenhauer, J.E.

    1987-08-25

    A support system for connection to an outer surface of a J-shaped steam generator for use with a nuclear reactor or other liquid metal cooled power source is disclosed. The J-shaped steam generator is mounted with the bent portion at the bottom. An arrangement of elongated rod members provides both horizontal and vertical support for the steam generator. The rod members are interconnected to the steam generator assembly and a support structure in a manner which provides for thermal distortion of the steam generator without the transfer of bending moments to the support structure and in a like manner substantially minimizes forces being transferred between the support structure and the steam generator as a result of seismic disturbances. 4 figs.

  2. Steam generator support system

    DOEpatents

    Moldenhauer, James E.

    1987-01-01

    A support system for connection to an outer surface of a J-shaped steam generator for use with a nuclear reactor or other liquid metal cooled power source. The J-shaped steam generator is mounted with the bent portion at the bottom. An arrangement of elongated rod members provides both horizontal and vertical support for the steam generator. The rod members are interconnected to the steam generator assembly and a support structure in a manner which provides for thermal distortion of the steam generator without the transfer of bending moments to the support structure and in a like manner substantially minimizes forces being transferred between the support structure and the steam generator as a result of seismic disturbances.

  3. Liquid ventilation.

    PubMed

    Sarkar, Suman; Paswan, Anil; Prakas, S

    2014-01-01

    Human have lungs to breathe air and they have no gills to breath liquids like fish. When the surface tension at the air-liquid interface of the lung increases as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV) is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen as the inert carrier of oxygen and carbon dioxide offers a number of advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. It is well-known that respiratory diseases are one of the most common causes of morbidity and mortality in intensive care unit. During the past few years several new modalities of treatment have been introduced. One of them and probably the most fascinating, is of LV. Partial LV, on which much of the existing research has concentrated, requires partial filling of lungs with perfluorocarbons (PFC's) and ventilation with gas tidal volumes using conventional mechanical ventilators. Various physico-chemical properties of PFC's make them the ideal media. It results in a dramatic improvement in lung compliance and oxygenation and decline in mean airway pressure and oxygen requirements. No long-term side-effect reported. PMID:25886321

  4. Liquid bridge formation

    NASA Astrophysics Data System (ADS)

    Sanz, A.; Perales, J. M.

    1989-10-01

    The formation of a liquid bridge is obviously the first step in the experimentation of the different aspects of the liquid bridge dynamics. Among the several candidate procedures of formation, the so-called 'cylindrical formation' has been selected; liquid is injected inside of the bridge through one of the supporting disks whereas simultaneously one of the disks is moved apart from the other at the proper speed to keep the volume of liquid inside the column, the same as that of the cylinder limited by both disks. Besides its own fluid mechanics interest (interplay between a jet and an interface), the results of this study would be very useful for experimenters in order to reduce the experiment preparation phase, as the total time allowed is scarce in most often used reduced gravity facilities (parabolic flights, sounding rockets and so on). A simplified theoretical model of the problem is presented which is valid in a flow regime limited in range by the Reynolds number of the injection jet. The existence of contiguous regimes and the influence of Ohnesorge number are suggested. This characterization has been deduced from the experiments performed by using the neutral buoyancy technique on earth and helps to explain the behavior observed during experiments performed on microgravity conditions onboard sounding rockets (TEXUS).

  5. Liquid-liquid driven cavity flow

    SciTech Connect

    Mansell, G.; Walter, J.; Marschall, E. )

    1994-02-01

    Liquid-liquid driven cavity flow was studied numerically. Information on [open quotes]realistic[close quotes] liquid-liquid interface conditions were obtained from photochromic flow visualization experiments. With this input, numerically obtained flow fields agreed well with experimentally observed flow fields. A parametric numerical study showed the influence of various parameters on the behavior of interface velocity and tangential shear stress gradient in the vicinity of the liquid-liquid interface. 24 refs., 16 figs.

  6. Supported inorganic membranes

    DOEpatents

    Sehgal, Rakesh (Albuquerque, NM); Brinker, Charles Jeffrey (Albuquerque, NM)

    1998-01-01

    Supported inorganic membranes capable of molecular sieving, and methods for their production, are provided. The subject membranes exhibit high flux and high selectivity. The subject membranes are substantially defect free and less than about 100 nm thick. The pores of the subject membranes have an average critical pore radius of less than about 5 .ANG., and have a narrow pore size distribution. The subject membranes are prepared by coating a porous substrate with a polymeric sol, preferably under conditions of low relative pressure of the liquid constituents of the sol. The coated substrate is dried and calcined to produce the subject supported membrane. Also provided are methods of derivatizing the surface of supported inorganic membranes with metal alkoxides. The subject membranes find use in a variety of applications, such as the separation of constituents of gaseous streams, as catalysts and catalyst supports, and the like.

  7. Liquid filtration simulation

    SciTech Connect

    Corey, I.; Bergman, W.

    1996-06-01

    We have a developed a computer code that simulates 3-D filtration of suspended particles in fluids in realistic filter structures. This code, being the most advanced filtration simulation package developed to date, provides LLNL and DOE with new capabilities to address problems in cleaning liquid wastes, medical fluid cleaning, and recycling liquids. The code is an integrated system of commercially available and LLNL-developed software; the most critical are the computational fluid dynamics (CFD) solver and the particle transport program. For the CFD solver, we used a commercial package based on Navier-Stokes equations and a LLNL-developed package based on Boltzman-lattice gas equations. For the particle transport program, we developed a cod based on the 3-D Langevin equation of motion and the DLVO theory of electrical interactions. A number of additional supporting packages were purchased or developed to integrate the simulation tasks and to provide visualization output.

  8. Liquid electrode

    DOEpatents

    Ekechukwu, Amy A. (Augusta, GA)

    1994-01-01

    A dropping electrolyte electrode for use in electrochemical analysis of non-polar sample solutions, such as benzene or cyclohexane. The liquid electrode, preferably an aqueous salt solution immiscible in the sample solution, is introduced into the solution in dropwise fashion from a capillary. The electrolyte is introduced at a known rate, thus, the droplets each have the same volume and surface area. The electrode is used in making standard electrochemical measurements in order to determine properties of non-polar sample solutions.

  9. Vapor liquid solid-hydride vapor phase epitaxy (VLS-HVPE) growth of ultra-long defect-free GaAs nanowires: Ab initio simulations supporting center nucleation

    NASA Astrophysics Data System (ADS)

    Andr, Yamina; Lekhal, Kaddour; Hoggan, Philip; Avit, Geoffrey; Cadiz, Fabian; Rowe, Alistair; Paget, Daniel; Petit, Elodie; Leroux, Christine; Trassoudaine, Agns; Rda Ramdani, M.; Monier, Guillaume; Colas, David; Ajib, Rabih; Castelluci, Dominique; Gil, Evelyne

    2014-05-01

    High aspect ratio, rod-like and single crystal phase GaAs nanowires (NWs) were grown by gold catalyst-assisted hydride vapor phase epitaxy (HVPE). High resolution transmission electron microscopy and micro-Raman spectroscopy revealed polytypism-free zinc blende (ZB) NWs over lengths of several tens of micrometers for a mean diameter of 50 nm. Micro-photoluminescence studies of individual NWs showed linewidths smaller than those reported elsewhere which is consistent with the crystalline quality of the NWs. HVPE makes use of chloride growth precursors GaCl of which high decomposition frequency after adsorption onto the liquid droplet catalysts, favors a direct and rapid introduction of the Ga atoms from the vapor phase into the droplets. High influxes of Ga and As species then yield high axial growth rate of more than 100 ?m/h. The diffusion of the Ga atoms in the liquid droplet towards the interface between the liquid and the solid nanowire was investigated by using density functional theory calculations. The diffusion coefficient of Ga atoms was estimated to be 3 10-9 m2/s. The fast diffusion of Ga in the droplet favors nucleation at the liquid-solid line interface at the center of the NW. This is further evidence, provided by an alternative epitaxial method with respect to metal-organic vapor phase epitaxy and molecular beam epitaxy, of the current assumption which states that this type of nucleation should always lead to the formation of the ZB cubic phase.

  10. Microfabricated Liquid Rocket Motors

    NASA Technical Reports Server (NTRS)

    Epstein, Alan H.; Joppin, C.; Kerrebrock, J. L.; Schneider, Steven J. (Technical Monitor)

    2003-01-01

    Under NASA Glenn Research Center sponsorship, MIT has developed the concept of micromachined, bipropellant, liquid rocket engines. This is potentially a breakthrough technology changing the cost-performance tradeoffs for small propulsion systems, enabling new applications, and redefining the meaning of the term low-cost-access-to-space. With this NASA support, a liquid-cooled, gaseous propellant version of the thrust chamber and nozzle was designed, built, and tested as a first step. DARPA is currently funding MIT to demonstrate turbopumps and controls. The work performed herein was the second year of a proposed three-year effort to develop the technology and demonstrate very high power density, regeneratively cooled, liquid bipropellant rocket engine thrust chamber and nozzles. When combined with the DARPA turbopumps and controls, this work would enable the design and demonstration of a complete rocket propulsion system. The original MIT-NASA concept used liquid oxygen-ethanol propellants. The military applications important to DARPA imply that storable liquid propellants are needed. Thus, MIT examined various storable propellant combinations including N2O4 and hydrazine, and H2O2 and various hydrocarbons. The latter are preferred since they do not have the toxicity of N2O4 and hydrazine. In reflection of the newfound interest in H2O2, it is once again in production and available commercially. A critical issue for the microrocket engine concept is cooling of the walls in a regenerative design. This is even more important at microscale than for large engines due to cube-square scaling considerations. Furthermore, the coolant behavior of rocket propellants has not been characterized at microscale. Therefore, MIT designed and constructed an apparatus expressly for this purpose. The report details measurements of two candidate microrocket fuels, JP-7 and JP-10.

  11. Rotating electric machine with fluid supported parts

    DOEpatents

    Smith, Jr., Joseph L.; Kirtley, Jr., James L.

    1981-01-01

    A rotating electric machine in which the armature winding thereof and other parts are supported by a liquid to withstand the mechanical stresses applied during transient overloads and the like. In particular, a narrow gap is provided between the armature winding and the stator which supports it and this gap is filled with an externally pressurized viscous liquid. The liquid is externally pressurized sufficiently to balance the static loads on the armature winding. Transient mechanical loads which deform the armature winding alter the gap dimensions and thereby additionally pressurize the viscous liquid to oppose the armature winding deformation and more nearly uniformly to distribute the resulting mechanical stresses.

  12. Method of forming supported doped palladium containing oxidation catalysts

    DOEpatents

    Mohajeri, Nahid

    2014-04-22

    A method of forming a supported oxidation catalyst includes providing a support comprising a metal oxide or a metal salt, and depositing first palladium compound particles and second precious metal group (PMG) metal particles on the support while in a liquid phase including at least one solvent to form mixed metal comprising particles on the support. The PMG metal is not palladium. The mixed metal particles on the support are separated from the liquid phase to provide the supported oxidation catalyst.

  13. Liquid metal flow encasing a magnetic cavity

    SciTech Connect

    Hassam, A. B.; Drake, J. F.; Goel, Deepak; Lathrop, D. P.

    2000-04-01

    A stationary equilibrium of a liquid metal flowing past a cylindrical magnetic cavity is presented. The cavity has an azimuthal magnetic field and can also have an axial field. The liquid metal flow can be maintained by a sufficiently high pressure head. The scheme could be used to support a flowing liquid wall for systems producing high heat fluxes. (c) 2000 American Institute of Physics.

  14. Models for Liquid Impact Onboard Sloshsat FLEVO

    NASA Technical Reports Server (NTRS)

    Vreeburg, Jan P. B.; Chato, David J.

    2000-01-01

    Orbital experiments on the behavior of liquid in spacecraft are planned. The Sloshsat free-flyer is described. Preparation of the experiments, and later evaluation, are supported by models of varying complexity. The characteristics of the models are discussed. Particular attention is given to the momentum transfer between the liquid and the spacecraft, in connection with the liquid impact that may occur at the end of a reorientation maneuver of the spacecraft.

  15. Pump for Saturated Liquids

    NASA Technical Reports Server (NTRS)

    Elliott, D. G.

    1986-01-01

    Boiling liquids pumped by device based on proven components. Expanding saturated liquid in nozzle and diverting its phases along separate paths in liquid/vapor separator raises pressure of liquid. Liquid cooled in process. Pump makes it unnecessary to pressurize cryogenic liquids in order to pump them. Problems of introducing noncondensable pressurizing gas avoided.

  16. Liquid ventilation: it's not science fiction anymore.

    PubMed

    Norris, M K; Fuhrman, B P; Leach, C L

    1994-08-01

    Liquid ventilation is, by all initial considerations, an unconventional concept. Decades of research, however, have found that by using perfluorocarbons, which are capable of holding high concentrations of critical gases such as oxygen and carbon dioxide, gas exchange optimal enough to support life is possible with no known toxic effects. The earliest method of liquid ventilation, tidal liquid breathing, involved infusion and active removal of tidal volumes of perfluorocarbons by a liquid ventilator for gas exchange. Recently, a new method of partial liquid breathing, called perfluorocarbon-associated gas exchange, makes the process of liquid ventilation simpler by using conventional gas ventilators. Current research is showing great promise in the use of liquid ventilation for patients with pulmonary pathology. Critical care nurses should become knowledgeable of this new mode of ventilation and be prepared to meet the special needs of this unique population. PMID:7780839

  17. Geminate recombination in liquid argon

    NASA Astrophysics Data System (ADS)

    Freeman, Gordon R.

    1984-04-01

    The extended Onsager model for geminate neutralization is supported by the field dependence of the ionization yield in liquid argon irradiated by high energy electrons or x rays. Attempts to employ the model fail unless the distribution of initial separation distances between the thermalized electrons and their sibling ions (secondary electron thermalization ranges) is included. Data of Scalettar and co-workers are reanalyzed.

  18. Liquid electrode

    DOEpatents

    Ekechukwu, A.A.

    1994-07-05

    A dropping electrolyte electrode is described for use in electrochemical analysis of non-polar sample solutions, such as benzene or cyclohexane. The liquid electrode, preferably an aqueous salt solution immiscible in the sample solution, is introduced into the solution in dropwise fashion from a capillary. The electrolyte is introduced at a known rate, thus, the droplets each have the same volume and surface area. The electrode is used in making standard electrochemical measurements in order to determine properties of non-polar sample solutions. 2 figures.

  19. Systems and methods for analyzing liquids under vacuum

    DOEpatents

    Yu, Xiao-Ying; Yang, Li; Cowin, James P.; Iedema, Martin J.; Zhu, Zihua

    2013-10-15

    Systems and methods for supporting a liquid against a vacuum pressure in a chamber can enable analysis of the liquid surface using vacuum-based chemical analysis instruments. No electrical or fluid connections are required to pass through the chamber walls. The systems can include a reservoir, a pump, and a liquid flow path. The reservoir contains a liquid-phase sample. The pump drives flow of the sample from the reservoir, through the liquid flow path, and back to the reservoir. The flow of the sample is not substantially driven by a differential between pressures inside and outside of the liquid flow path. An aperture in the liquid flow path exposes a stable portion of the liquid-phase sample to the vacuum pressure within the chamber. The radius, or size, of the aperture is less than or equal to a critical value required to support a meniscus of the liquid-phase sample by surface tension.

  20. Vapor liquid solid-hydride vapor phase epitaxy (VLS-HVPE) growth of ultra-long defect-free GaAs nanowires: Ab initio simulations supporting center nucleation

    SciTech Connect

    André, Yamina Lekhal, Kaddour; Hoggan, Philip; Avit, Geoffrey; Réda Ramdani, M.; Monier, Guillaume; Colas, David; Ajib, Rabih; Castelluci, Dominique; Gil, Evelyne; Cadiz, Fabian; Rowe, Alistair; Paget, Daniel; Petit, Elodie; Leroux, Christine; Trassoudaine, Agnès

    2014-05-21

    High aspect ratio, rod-like and single crystal phase GaAs nanowires (NWs) were grown by gold catalyst-assisted hydride vapor phase epitaxy (HVPE). High resolution transmission electron microscopy and micro-Raman spectroscopy revealed polytypism-free zinc blende (ZB) NWs over lengths of several tens of micrometers for a mean diameter of 50 nm. Micro-photoluminescence studies of individual NWs showed linewidths smaller than those reported elsewhere which is consistent with the crystalline quality of the NWs. HVPE makes use of chloride growth precursors GaCl of which high decomposition frequency after adsorption onto the liquid droplet catalysts, favors a direct and rapid introduction of the Ga atoms from the vapor phase into the droplets. High influxes of Ga and As species then yield high axial growth rate of more than 100 μm/h. The diffusion of the Ga atoms in the liquid droplet towards the interface between the liquid and the solid nanowire was investigated by using density functional theory calculations. The diffusion coefficient of Ga atoms was estimated to be 3 × 10{sup −9} m{sup 2}/s. The fast diffusion of Ga in the droplet favors nucleation at the liquid-solid line interface at the center of the NW. This is further evidence, provided by an alternative epitaxial method with respect to metal-organic vapor phase epitaxy and molecular beam epitaxy, of the current assumption which states that this type of nucleation should always lead to the formation of the ZB cubic phase.

  1. Peer Support.

    PubMed

    Forchuk, Cheryl; Solomon, Michelle; Viran, Tazim

    2016-01-01

    The Mental Health Commission of Canada defines peer support as "a supportive relationship between people who have a lived experience in common in relation to a mental health challenge or illness related to their own mental health or that of a loved one" (Sunderland et al. 2013: 11). In Ontario, a key resource for peer support is the Ontario Peer Development Initiative (OPDI), which is an umbrella organization of mental health Consumer/Survivor Initiatives (CSIs) and peer support organizations across the province of Ontario. Member organizations are run by and for people with lived experience of a mental health or addiction issue and provide a wide range of services and activities within their communities. The central tenet of member organizations is the common understanding that people can and do recover with the proper supports in place and that peer support is integral to successful recovery. Nationally, Peer Support Accreditation and Certification Canada has recently been established. The relatively new national organization focuses on training and accrediting peer support workers. This paper focuses on a range of diverse peer support groups and CSIs that operate in London and surrounding areas. PMID:26854546

  2. Bearing for liquid metal pump

    DOEpatents

    Dickinson, Robert J. (Shaler Township, Allegheny County, PA); Wasko, John (Plum Borough, PA); Pennell, William E. (Unity Township, Allegheny County, PA)

    1984-01-01

    A liquid metal pump bearing support comprises a series of tangentially oriented spokes that connect the bearing cylinder to the pump internals structure. The spokes may be arranged in a plurality of planes extending from the bearing cylinder to the pump internals with the spokes in one plane being arranged alternately with those in the next plane. The bearing support structure provides the pump with sufficient lateral support for the bearing structure together with the capability of accommodating differential thermal expansion without adversely affecting pump performance.

  3. Liquid metal-cooled nuclear reactor

    SciTech Connect

    Kayser, G.

    1982-12-07

    Integrated nuclear reactor cooled by a liquid metal and incorporating a main vessel sealed in its upper part by a slab, an inner vessel containing the core, the latter resting on a system for the positioning and supply of the core with liquid metal and which is called the support, the latter itself resting on a supporting structure bearing on the bottom of the main vessel of the reactor, wherein it comprises an inner baffle cladding the side wall and bottom of the main vessel and defining with the latter an intermediate space filled with the liquid metal, tubes for supplying a liquid metal to the intermediate space below the bottom of the main vessel and tubes for returning said liquid metal to an auxiliary exchanger in order to remove heat from the intermediate space.

  4. Family Support.

    ERIC Educational Resources Information Center

    Wieck, Colleen, Ed.; McBride, Marijo, Ed.

    1990-01-01

    This "Feature Issue" of the quarterly journal "Impact" presents 19 brief articles on family support systems in the United States for persons with developmental disabilities and their families. Emphasis is on provisions of Public Law 99-457. Articles include: "Family Support in the United States: Setting a Course for the 1990s" (James Knoll);…

  5. Supporting Teachers

    ERIC Educational Resources Information Center

    Lesaux, Nonie K.; Burkhauser, Mary A.; Kelley, Joan G.

    2013-01-01

    Material resources, personalized support, time to collaborate, and strong principal leadership are necessary for making curricular and instructional shifts. The authors of this article share the lessons they learned about supporting implementation of the Common Core State Standards. They draw on interviews with teachers, as well as field notes…

  6. Viscoelastic cushion for patient support

    NASA Technical Reports Server (NTRS)

    Sauers, D. G.

    1971-01-01

    Flexible container, filled with liquid, provides supportive device which conforms to patient's anatomy. Uniform cushion pressure prevents formation of decubitus ulcers, while the porous sponge substructure damps fluid movement through cushion response so that patient is not dumped when his weight shifts.

  7. Gauging Systems Monitor Cryogenic Liquids

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Rocket fuel needs to stay cool - super cool, in fact. The ability to store gas propellants like liquid hydrogen and oxygen at cryogenic temperatures (below -243 F) is crucial for space missions in order to reduce their volumes and allow their storage in smaller (and therefore, less costly) tanks. The Agency has used these cryogenic fluids for vehicle propellants, reactants, and life support systems since 1962 with the Centaur upper stage rocket, which was powered with liquid oxygen and liquid hydrogen. During proposed long-duration missions, super-cooled fluids will also be used in space power systems, spaceports, and lunar habitation systems. In the next generation of launch vehicles, gaseous propellants will be cooled to and stored for extended periods at even colder temperatures than currently employed via a process called densification. Densification sub-cools liquids to temperatures even closer to absolute zero (-459 F), increasing the fluid s density and shrinking its volume beyond common cryogenics. Sub-cooling cryogenic liquid hydrogen, for instance, from 20 K (-423 F) to 15 K (-432.4 F) reduces its mass by 10 percent. These densified liquid gases can provide more cost savings from reduced payload volume. In order to benefit from this cost savings, the Agency is working with private industry to prevent evaporation, leakage, and other inadvertent loss of liquids and gases in payloads - requiring new cryogenic systems to prevent 98 percent (or more) of boil-off loss. Boil-off occurs when cryogenic or densified liquids evaporate, and is a concern during launch pad holds. Accurate sensing of propellants aboard space vehicles is also critical for proper engine shutdown and re-ignition after launch, and zero boil-off fuel systems are also in development for the Altair lunar lander.

  8. Thermal support for scale support

    NASA Technical Reports Server (NTRS)

    Dean, W. G.

    1976-01-01

    The thermal design work completed for the Thermal Protection System (TPS) of the Space Shuttle System (TPS) of the space shuttle vehicle was documented. This work was divided into three phases, the first two of which reported in previous documents. About 22 separate tasks were completed in phase III, such as: hot gas facility (HGF) support, guarded tank support, shuttle external tank (ET) thermal design handbook support, etc.

  9. Liquid Crystal Devices.

    ERIC Educational Resources Information Center

    Bradshaw, Madeline J.

    1983-01-01

    The nature of liquid crystals and several important liquid crystal devices are described. Ideas for practical experiments to illustrate the properties of liquid crystals and their operation in devices are also described. (Author/JN)

  10. Liquid Crystal Inquiries.

    ERIC Educational Resources Information Center

    Marroum, Renata-Maria

    1996-01-01

    Discusses the properties and classification of liquid crystals. Presents a simple experiment that illustrates the structure of liquid crystals and the differences between the various phases liquid crystals can assume. (JRH)

  11. Synthesis, structural characterization and reactivity of aluminium complexes supported by benzotriazole phenoxide ligands: air-stable alumoxane as an efficient catalyst for ring-opening polymerization of L-lactide.

    PubMed

    Li, Chen-Yu; Tsai, Chen-Yen; Lin, Chia-Her; Ko, Bao-Tsan

    2011-03-01

    Aluminium complexes bearing sterically bulky benzotriazole-phenoxide ligands are synthesized and characterized structurally. The reaction of 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol ((CMe2Ph)BTP-H) or 2-(2H-benzotriazol-2-yl)-4,6-di-tert-butylphenol ((t-Bu)BTP-H) with AlMe(3) (1.2 molar equiv.) in toluene yields [((CMe2Ph)BTP)AlMe(2)] (1) or [((t-Bu)BTP)AlMe(2)] (2) as a four-coordinated monomeric aluminium complex. Compound 1 reacts further with (CMe2Ph)BTP-H in a stoichiometric proportion, affording penta-coordinated monomeric aluminium methyl complex [((CMe2Ph)BTP)(2)AlMe] (3). Complex 3 is also obtained directly upon treatment of AlMe(3) with (CMe2Ph)BTP-H (two molar equiv.) in refluxing toluene in high yield. In the presence of H(2)O (half a molar equiv.), hydrolysis of 3 in a mixed solvent of THF and toluene at ambient temperature affords [{((CMe2Ph)BTP)(2)Al}(2)(?-O)] (4), in which the oxo ligand acts as a chelating group linearly bridging two aluminium centers. Air-stable alumoxane 4 is an efficient catalyst for the ring-opening polymerization of L-lactide (L-LA) in the presence of 9-anthracenemethanol (9-AnOH). Complex 4 catalyzes the polymerization of L-LA in a controlled manner, yielding PLLAs with the expected molecular weights and narrow polydispersity indices (PDIs). PMID:21283858

  12. Nutritional Support

    MedlinePLUS

    Nutritional support is therapy for people who cannot get enough nourishment by eating or drinking. You may need it if you Can't swallow Have problems with your appetite Are severely malnourished Can't ...

  13. Liquid-liquid extraction in flow analysis: A critical review.

    PubMed

    Silvestre, Cristina I C; Santos, João L M; Lima, José L F C; Zagatto, Elias A G

    2009-10-12

    Liquid-liquid extractions (LLE) are a common sample pre-treatment in many analytical applications. This review aims at providing a critical overview of the distinct automated continuous flow-based approaches that were developed for liquid-liquid extraction with the purpose of pre-concentration and/or separation of multiple analytes, such as ultra-trace metal and metalloid species, phenolic compounds, surfactants, pharmaceuticals, etc., hyphenated with many detection technique such as UV/vis spectrophotometry, atomic spectrometric detection systems and luminescent detectors, including distinct extraction strategies and applications like single and multiple extraction schemes, wetting film extraction, supported liquid membrane extraction, back extraction, closed-loop systems and the utilisation of zone sampling, chromatomembranes and iterative reversal techniques. The analytical performance of the developed flow-based LLE methods and the influence of flow manifold components such as the segmenter, extraction coil and phase separator, is emphasised and object of discussion. An overall presentation of each system components, selectivity, advantages and shortcomings is carried out and exemplified with selected applications. PMID:19786170

  14. Dynamics of Transient Liquid Injection

    NASA Astrophysics Data System (ADS)

    Sirignano, William

    2013-11-01

    Start-up transients and steady injection of liquid through round and annular orifices into ambient gas are examined. Various relevant hydrodynamic instabilities are examined together with their synergisms; capillary instability; vortex-ring (Widnall) instability; Kelvin-Helmholtz (i.e., shear-driven) instability; and Rayleigh-Taylor instability. Studies of both full jets and liquid segments of the jet are considered. Different instabilities and synergisms of instabilities produce different wavelengths on the jet interface. Surface waves, cone and sheet formations, and liquid-sheet tearing are examined. The breakdown of axisymmetry is related to the various instabilities. Accelerations of both the exit jet velocity and the liquid in the cones and ligaments are examined for Rayleigh-Taylor instabilities. Identification is sought of the length scales related to eventual breakup and droplet or ligament formation. Cavitation at high pressures is explained. Bubble growth and collapse in the internal orifice flow are discussed. Numerical problems with prediction of liquid stream breaking are discussed. Analysis and computations are emphasized but some experiments are discussed. Support from Army Research Office is acknowledged.

  15. Carbon supports from natural organic materials and carbon-supported palladium catalysts

    SciTech Connect

    Kuznetsov, B.N.

    2007-07-15

    Experimental data are presented concerning the influence of preparation conditions on the pore structure of carbon supports obtained from different types of plant biomass, thermally expanded graphites, and chemically modified anthracites, on the distribution and particle size of supported palladium, and on the activity of the supported catalyst in the liquid-phase hydrogenation of hex-1-ene and cyclohexene.

  16. Flame Spread Across Liquids

    NASA Technical Reports Server (NTRS)

    Ross, Howard D.; Miller, Fletcher J.; Sirignano, William A.; Schiller, David

    1997-01-01

    The principal goal of our recent research on flame spread across liquid pools is the detailed identification of the mechanisms that control the rate and nature of flame spread when the liquid pool is initially at an isothermal bulk temperature that is below the fuel's flash point temperature. In our project, we specialize the subject to highlight the roles of buoyancy-related processes regarding the mechanisms of flame spread, an area of research cited recently by Linan and Williams as one that needs further attention and which microgravity (micro-g) experiments could help to resolve. Toward resolving the effects of buoyancy on this flame spread problem, comparisons - between 1-g and micro-g experimental observations, and between model predictions and experimental data at each of these gravitational levels - are extensively utilized. The present experimental and computational foundation is presented to support identification of the mechanisms that control flame spread in the pulsating flame spread regime for which long-duration, micro-g flame spread experiments have been conducted aboard a sounding rocket.

  17. Retreating behavior of a charged ionic liquid droplet in a dielectric liquid under electric field

    NASA Astrophysics Data System (ADS)

    Ahn, Myung Mo; Im, Do Jin; Kang, In Seok

    2013-11-01

    Ionic liquids show great promise as excellent solvents or catalysts in energy and biological fields due to their unique chemical and physical properties. The ionic liquid droplets in microfluidic systems can also be used as a potential platform for chemical biological reactions. In order to control electrically the ionic liquid droplets in a microfluidic device, the charging characteristics of ionic liquid droplets need to be understood. In this work, the charging characteristics of various ionic liquids are investigated by using the parallel plate electrodes system. Under normal situation, a charged droplet shows bouncing motion between electrodes continuously. However, for some special ionic liquids, interesting retreating behavior of charged ionic liquid droplet has been observed. This retreating behavior of ionic liquid droplet has been analyzed experimentally by the image analysis and the electrometer signal analysis. Based on the hypothesis of charge leakage of the retreating ionic liquid droplets, FT-IR spectroscopy analysis has also been performed. The retreating behavior of ionic liquid droplet is discussed from the intermolecular point of view according to the species of ionic liquids. This research was supported by grant No. 2013R1A1A2011956 funded by the Ministry of Science, ICT and Future Planning (MSIP) and by grant No. 2013R1A1A2010483 funded by the Ministry of Education, Science and Technology (MEST) through the NRF.

  18. Shaped composite liquid marbles.

    PubMed

    Bormashenko, Edward; Balter, Revital; Aharoni, Hadas; Aurbach, Doron

    2014-03-01

    Shaped "cubic" non-stick droplets are reported. Shaped composite droplets were manufactured via a two-stage process. In the first stage, cubic foamed-polystyrene particles were hydrophilized with cold radiofrequency plasma. Then particles were wetted with water. In the second stage, they were coated with solid, colloidal particles such as lycopodium, Teflon or carbon black. Thus, "liquid marble"-like non-stick shaped droplets were obtained. The shaped "cubic" droplets remained stable when supported by a NaCl water solution. Shaped Janus droplets coated on one side with dielectric Teflon and with semiconductor carbon black on the other side, were prepared. Janus marbles were actuated with an electric field. PMID:24407678

  19. Ionic Liquids Database- (ILThermo)

    National Institute of Standards and Technology Data Gateway

    SRD 147 Ionic Liquids Database- (ILThermo) (Web, free access)   IUPAC Ionic Liquids Database, ILThermo, is a free web research tool that allows users worldwide to access an up-to-date data collection from the publications on experimental investigations of thermodynamic, and transport properties of ionic liquids as well as binary and ternary mixtures containing ionic liquids.

  20. Liquid crystal polyester thermosets

    SciTech Connect

    Benicewicz, B.C.; Hoyt, A.E.

    1990-01-01

    The present invention relates to the field of curable liquid crystal polyester monomers and to thermoset liquid crystalline polyester compositions prepared therefrom. It is an object of this invention to provide curable liquid crystalline polyester materials. Another object of this invention is to provide a process of preparing curable liquid crystal polyester monomers. Yet another object of this invention is to provide liquid crystalline blends of polyester materials. It is a further object of this invention to provide thermoset liquid crystalline polyester compositions. It is a still further object of this invention to provide thermoset liquid crystalline polyester compositions having a high heat resistance. 1 fig.

  1. Liquid crystal polyester thermosets

    SciTech Connect

    Benicewicz, B.C.; Hoyt, A.E.

    1990-12-31

    The present invention relates to the field of curable liquid crystal polyester monomers and to thermoset liquid crystalline polyester compositions prepared therefrom. It is an object of this invention to provide curable liquid crystalline polyester materials. Another object of this invention is to provide a process of preparing curable liquid crystal polyester monomers. Yet another object of this invention is to provide liquid crystalline blends of polyester materials. It is a further object of this invention to provide thermoset liquid crystalline polyester compositions. It is a still further object of this invention to provide thermoset liquid crystalline polyester compositions having a high heat resistance. 1 fig.

  2. Liquid metal cooled nuclear reactors

    SciTech Connect

    Scott, D.

    1984-07-03

    A liquid metal cooled nuclear reactor of the kind wherein a fuel assembly is supported on a diagrid and submerged in a pool of coolant is described. The diagrid comprises a plenum supported on a load bearing undershell and has an array of resilient spikes upstanding from the upper face of the plenum each for locating a fuel subassembly. The load of the fuel assembly is distributed over the upper face plate of the plenum and transmitted to the undershell by an array of strut members.

  3. Supporting Diversity.

    ERIC Educational Resources Information Center

    Horton, Betty, Ed.; And Others

    1996-01-01

    This newsletter feature issue focuses on services for persons with developmental disabilities that support the whole person by acknowledging, respecting, and incorporating aspects of identity such as race, ethnicity, religion, sexual orientation, gender, age, and class. Articles include: (1) "Serving the Whole Person: The Journey to Embracing…

  4. Mirror Support

    NASA Technical Reports Server (NTRS)

    Baron, Richard L. (Inventor)

    2013-01-01

    Disclosed herein is a method of making a mirror support comprising a composite, the composite comprising a plurality of carbon nanotubes, wherein at least two of the plurality of carbon nanotubes are bonded to each other through a bridging moiety bound to each of the two carbon nanotubes, and a laminate comprising the composite.

  5. Synthesis and high performance liquid chromatography/electrospray mass spectrometry single-bead decoding of split-pool structural libraries of polyamines supported on polystyrene and polystyrene/ethylene glycol resins.

    PubMed

    Manku, Sukhdev; Wang, Fan; Hall, Dennis G

    2003-01-01

    Natural polyamines are ubiquitous biomolecules present in all living cells. These cationic compounds play essential roles in both cell growth and differentiation and are known to interact in complex ways with polyanionic biomolecules. Consequently, there is significant interest in expanding nature's polyamine diversity using combinatorial synthesis and screening strategies. This article describes an efficient split-pool solid-phase synthetic strategy toward the generation of encoded libraries of polyamines via the exhaustive borane-promoted reduction of trityl-linked, resin-bound polyamides. Model structural libraries of tetra- and pentaamines were designed from a set of geometrically diverse amino acid building blocks. To encode the libraries, a partial termination synthesis approach was employed at the polyamide stage, allowing each library to be analyzed from single beads by HPLC/ESMS under two sets of conditions featuring both pH extremes. Determination of the sequence of polyamine residues was simply achieved by the mass differences observed between the full oligomers and the terminated ones. Both polystyrene- and TentaGel-supported libraries, including a library of 4913 pentaamines, were prepared and successfully decoded. For the TentaGel-supported libraries, suitable for on-bead aqueous screening of biomolecules, a novel trityl-derivatized resin was prepared in which the trityl group is anchored to the poly(ethylene glycol) chains via a methylene group. The resulting resin is much more resistant than other commercially available polystyrene-poly(ethylene glycol) trityl resins to the harsh borane reduction conditions required. Two workup conditions for the cleavage of the resultant borane-amine adducts were evaluated on the TentaGel bound polyamide 14. Although the two methods showed a comparable efficiency when using the polystyrene support, with 14 it was found that the piperidine-exchange method afforded polyamines of higher purity than the iodine-based oxidative method previously developed in our laboratory. PMID:12857106

  6. Research News: Emulsion Liquid Membrane Extraction in a Hollow-Fiber Contactor

    NASA Technical Reports Server (NTRS)

    Wiencek, John M.; Hu, Shih-Yao

    2000-01-01

    This article describes how ELMs (emulsion liquid membranes) can be used for extraction. The article addresses the disadvantages of ELM extraction in a stirred contactor, and the advantages of SELMs (supported emulsion liquid membranes). The introduction of the article provides background information on liquid-liquid solvent extraction and dispersion-free solvent extraction.

  7. Integrated continuous microfluidic liquid-liquid extraction.

    PubMed

    Kralj, Jason G; Sahoo, Hemantkumar R; Jensen, Klavs F

    2007-02-01

    We describe continuous flow liquid-liquid phase separation in microfluidic devices based on capillary forces and selective wetting surfaces. Effective liquid-liquid phase separation is achieved by using a thin porous fluoropolymer membrane that selectively wets non-aqueous solvents, has average pore sizes in the 0.1-1 microm range, and has a high pore density for high separation throughput. Pressure drops throughout the microfluidic network are modelled and operating regimes for the membrane phase separator are determined based on hydrodynamic pressure drops and capillary forces. A microfluidic extraction device integrating mixing and phase separation is realized by using silicon micromachining. Modeling of the phase separator establishes the operating limits. The device is capable of completely separating several organic-aqueous and fluorous-aqueous liquid-liquid systems, even with high fractions of partially miscible compounds. In each case, extraction is equivalent to one equilibrium extraction stage. PMID:17268629

  8. Liquid Polyamorphism and the Anomalous Behavior of Water

    NASA Astrophysics Data System (ADS)

    Stanley, H. E.; Buldyrev, S. V.; Chen, S.-H.; Franzese, G.; Han, S.; Kumar, P.; Mallamace, F.; Mazza, M. G.; Xu, L.; Yan, Z.

    We present evidence from experiments and computer simulations supporting the hypothesis that ?dex{polyamorphism}water displays polyamorphism, i.e., water separates into two distinct liquid phases. This concept of a new ?dex{liquid-liquid phase transition}liquid-liquid phase transition is finding potential application to other liquids as well as water, such as silicon and silica. Here we review the relation between changes in dynamic and thermodynamic anomalies arising from the presence of the liquid-liquid critical point in (i) Two models of water, TIP5P and ST2, which display a first order liquid-liquid phase transition at low temperatures; (ii) Two spherically symmetric two-scale potentials known to possess a liquid-liquid critical point, in which the competition between two liquid structures is generated by repulsive and attractive ramp interactions; and (iii) A Hamiltonian model of water where the idea of two length/energy scales is built in. This model also displays a first order liquid-liquid phase transition at low temperatures besides the first order liquid-gas phase transition at high temperatures. We find a correlation between the dynamic fragility crossover and the locus of specific heat maxima CP max ("Widom line") emanating from the critical point. Our findings are consistent with a possible relation between the previously hypothesized liquid-liquid phase transition and the transition in the dynamics recently observed in neutron scattering experiments on confined water. More generally, we argue that this connection between C{P/max} and the dynamic crossover is not limited to the case of water, a hydrogen bonded network liquid, but is a more general feature of crossing the Widom line, an extension of the first-order coexistence line in the supercritical region.

  9. Liquid level detector

    DOEpatents

    Grasso, A.P.

    1984-02-21

    A liquid level detector for low pressure boilers. A boiler tank, from which vapor, such as steam, normally exits via a main vent, is provided with a vertical side tube connected to the tank at the desired low liquid level. When the liquid level falls to the level of the side tube vapor escapes therethrough causing heating of a temperature sensitive device located in the side tube, which, for example, may activate a liquid supply means for adding liquid to the boiler tank. High liquid level in the boiler tank blocks entry of vapor into the side tube, allowing the temperature sensitive device to cool, for example, to ambient temperature.

  10. Liquid level detector

    DOEpatents

    Grasso, Albert P. (Vernon, CT)

    1986-01-01

    A liquid level detector for low pressure boilers. A boiler tank, from which apor, such as steam, normally exits via a main vent, is provided with a vertical side tube connected to the tank at the desired low liquid level. When the liquid level falls to the level of the side tube vapor escapes therethrough causing heating of a temperature sensitive device located in the side tube, which, for example, may activate a liquid supply means for adding liquid to the boiler tank. High liquid level in the boiler tank blocks entry of vapor into the side tube, allowing the temperature sensitive device to cool, for example, to ambient temperature.

  11. Atmospheric Pressure Glow Discharge with Liquid Electrode

    NASA Astrophysics Data System (ADS)

    Tochikubo, Fumiyoshi

    2013-09-01

    Nonthermal atmospheric pressure plasmas in contact with liquid are widely studied aiming variety of plasma applications. DC glow discharge with liquid electrode is an easy method to obtain simple and stable plasma-liquid interface. When we focus attention on liquid-phase reaction, the discharge system is considered as electrolysis with plasma electrode. The plasma electrode will supply electrons and positive ions to the liquid surface in a different way from the conventional metal electrode. However, the phenomena at plasma-liquid interface have not been understood well. In this work, we studied physical and chemical effect in liquid induced by dc atmospheric pressure glow discharge with liquid electrode. The experiment was carried out using H-shaped Hoffman electrolysis apparatus filled with electrolyte, to separate the anodic and cathodic reactions. Two nozzle electrodes made of stainless steel are set about 2 mm above the liquid surface. By applying a dc voltage between the nozzle electrodes, dc glow discharges as plasma electrodes are generated in contact with liquid. As electrolyte, we used aqueous solutions of NaCl, Na2SO4, AgNO3 and HAuCl4. AgNO3 and HAuCl4 are to discuss the reduction process of metal ions for synthesis of nanoparticles (NPs). OH radical generation yield in liquid was measured by chemical probe method using terephthalic acid. Discharge-induced liquid flow was visualized by Schlieren method. Electron irradiation to liquid surface (plasma cathode) generated OH- and OH radical in liquid while positive ion irradiation (plasma anode) generated H+ and OH radical. The generation efficiency of OH radical was better with plasma anode. Both Ag NPs in AgNO3 and Au NPs in HAuCl4 were synthesized with plasma cathode while only Au NPs were generated with plasma anode. Possible reaction process is qualitatively discussed. The discharge-induced liquid flow such as convection pattern was strongly influenced by the gas flow on the liquid surface. This work was supported financially in part by Kakenhi (No 2111007), Japan.

  12. Carbon cloth supported electrode

    DOEpatents

    Lu, Wen-Tong P. (Upper St. Clair, PA); Ammon, Robert L. (Baldwin both of, PA)

    1982-01-01

    A flow-by anode is disclosed made by preparing a liquid suspension of about to about 18% by weight solids, the solids comprising about 3.5 to about 8% of a powdered catalyst of platinum, palladium, palladium oxide, or mixtures thereof; about 60 to about 76% carbon powder (support) having a particle size less than about 20 m.mu.m and about 20 to about 33% of an inert binder having a particle size of less than about 500 m.mu.m. A sufficient amount of the suspension is poured over a carbon cloth to form a layer of solids about 0.01 to about 0.05 cm thick on the carbon cloth when the electrode is completed. A vacuum was applied to the opposite side of the carbon cloth to remove the liquid and the catalyst layer/cloth assembly is dried and compressed at about 10 to about 50 MPa's. The binder is then sintered in an inert atmosphere to complete the electrode. The electrode is used for the oxidation of sulfur dioxide in a sulfur based hybrid cycle for the decomposition of water.

  13. A Liquid Sodium ? ? Dynamo Experiment

    NASA Astrophysics Data System (ADS)

    Colgate, Stirling; Beckley, Howard; Li, Hui; Sonnenfield, Richard; Westpfahl, Dave; Bentley, Ian; Ginanni, Rocky; McKinnly, Travis; Pariev, Valadimir

    2004-11-01

    A Liquid Sodium ? ? Dynamo Experiment; Stirling Colgate, Howard Beckley, Hui Li, Richard Sonnenfeld, Dave Westpfahl, Ian Bentley, Rocky Ginanni, Travis Mckinnly, and Valadimir Pariev, LANL, NMIMT, & Univ. of Rochester. A liquid sodium ? ? dynamo experiment has been constructed at NMIMT to simulate MRI, dynamo gain, and feed back in liquid sodium (r1 = 15 cm,; r2 = 30 cm,; L=30 cm,; f1 = 120 Hz,; f2 = 30 Hz ). It is designed to simulate the generation of large scale magnetic fields in massive black hole accretion disks, galaxies, and stars. The omega gain is due to the shear flow of differential rotation of Couette flow between two differentially rotating co-axial cylinders. Differential rotation in a conducting fluid twists a radial or quadrupole magnetic flux into a greatly enhanced toroidal flux. A large coherent helicity is produced by driven plumes and astrophisically by star-disk collisions, supernova explosions, or large scale plume convection respectively. We have rotated the apparatus with water and hot oil and demonstrated stable Couette flow with only Ekman-flow-induced torque. We will report on the ? gain with liquid sodium. This Work has been supported by NMIMT, EMRTC, NSF, & LDRD of LANL.

  14. Liquid-film electron stripper

    DOEpatents

    Gavin, Basil F. (Albion, CA)

    1986-01-01

    An improved liquid-film electron stripper particularly for high intensity heavy ion beams which produces constant regenerated, stable, free-standing liquid films having an adjustable thickness between 0.3 to 0.05 microns. The improved electron stripper is basically composed of at least one high speed, rotating disc with a very sharp, precision-like, ground edge on one said of the disc's periphery and with a highly polished, flat, radial surface adjacent the sharp edge. A fine stream of liquid, such as oil, impinges at a 90.degree. angle adjacent the disc's sharp outer edge. Film terminators, located at a selected distance from the disc perimeter are positioned approximately perpendicular to the film. The terminators support, shape, and stretch the film and are arranged to assist in the prevention of liquid droplet formation by directing the collected film to a reservoir below without breaking or interfering with the film. One embodiment utilizes two rotating discs and associated terminators, with the discs rotating so as to form films in opposite directions, and with the second disc being located down beam-line relative to the first disc.

  15. Floating liquid bridge charge dynamics

    NASA Astrophysics Data System (ADS)

    Teschke, Omar; Soares, David Mendez; Gomes, Whyllerson Evaristo; Valente Filho, Juracyr Ferraz

    2016-01-01

    The interaction of liquid with electric fields is investigated in a configuration where up to 13 kV are applied between electrodes resulting in a 106 V/m electric field in the capillaries and where there is the formation of a free-standing fluid bridge in the interelectrode gap. The Mott-Gurney equation was fitted to the measured ionization current vs applied voltage curve which indicates that the ionization rate at the high-voltage anode electrode dimethylsulfoxide (DMSO) interface and space charging in the interelectrode gap determine the floating liquid bridge current for a given cathode-to-anode voltage. Space charge effects were measured in the cathode becker and also at the liquid bridge since the ionized charges at the anode migrate to the bridge outer surface and decrease the interfacial tension from 43 mJ/m2 to 29 mJ/m2. Two distinct structural regions then form the bridge, a charged plastic (bulk modulus 100 MPa) conducting outer layer with a surface conductivity of 10-9 ?-1, which shapes and supports the floating fluid structure, and an inner liquid cylinder, where DMSO molecules flow.

  16. Liquid seeding atomizer

    NASA Technical Reports Server (NTRS)

    Seegmiller, Henry L. B. (Inventor)

    1987-01-01

    An atomizer for a liquid having an air supply is described. Liquid supply tubes extend longitudinally along the air supply tube. The air supply tube has at least one air orifice extending from an inner surface of the tube through the tube. The liquid supply tubes are positioned on either side of the air orifices and the liquid tubes are sealed to the air supply tube. The liquid supply tubes with facing liquid orifices are positioned adjacent to each of the air orifices. The liquid supply tubes are laterally spaced apart at the liquid orifices at a distance less than the diameter of the air orifices to enable a beneficial venturi effect when the atomizer is in operation.

  17. Tool to Prioritize Energy Efficiency Investments

    SciTech Connect

    Farese, Philip; Gelman, Rachel; Hendron, Robert

    2012-08-01

    To provide analytic support of the U.S. Department of Energy's Office of the Building Technology Program (BTP), NREL developed a Microsoft Excel-based tool to provide an open and objective comparison of the hundreds of investment opportunities available to BTP. This tool uses established methodologies to evaluate the energy savings and cost of those savings.

  18. Instantaneous Liquid Interfaces

    PubMed Central

    Willard, Adam P.; Chandler, David

    2010-01-01

    We describe and illustrate a simple procedure for identifying a liquid interface from atomic coordinates. In particular, a coarse grained density field is constructed, and the interface is defined as a constant density surface for this coarse grained field. In applications to a molecular dynamics simulation of liquid water, it is shown that this procedure provides instructive and useful pictures of liquid-vapor interfaces and of liquid-protein interfaces. PMID:20055377

  19. Fluid Mechanics of Liquid-Liquid Systems.

    NASA Astrophysics Data System (ADS)

    Richards, John Reed

    The detailed hydrodynamics of selected liquid -liquid flow systems are investigated to provide a firm foundation for the rational design of separation processes. The implementation of this objective centers on the development of a robust code to simulate liquid-liquid flows. We have applied this code to the realistic simulation of aspects of the complex fluid mechanical behavior, and developed quantitative insight into the underlying processes involved. The Volume of Fluid (VOF) method is combined with the Continuous Surface Force (CSF) algorithm to provide a numerically stable code capable of solving high Reynolds numbers free surface flows. One of the developments during the testing was an efficient method for solving the Young-Laplace equation describing the shape of the meniscus in a vertical cylinder for a constrained liquid volume. The steady-state region near the nozzle for the laminar flow of a Newtonian liquid jet injected vertically into another immiscible Newtonian liquid is investigated for various Reynolds numbers by solving the axisymmetric transient equations of motion and continuity. The analysis takes into account pressure, viscous, inertial, gravitational, and surface tension forces, and comparison with previous experimental measurements shows good agreement. Comparisons of the present numerical method with the numerical results of previous boundary-layer methods help establish their range of validity. A new approximate equation for the shape of the interface of the steady jet, based on an overall momentum balance, is also developed. The full transient from liquid-liquid jet startup to breakup into drops is also simulated numerically. In comparison with experiment, the results of the present numerical method show a greater sensitivity of the jet length to the Reynolds number than the best predictions of previous linear stability analyses. The formation of drops is investigated at low to high Reynolds numbers before and after jet formation. The numerical simulations are satisfactorily compared with n-heptane/water experiments and previous simplified analyses based on drop formation before and after jetting. Although the program and numerical techniques developed in this dissertation have been used mainly to solve problems involving liquid-liquid jets and drops, many features of more complex and general liquid-liquid contacting systems are explored in the process.

  20. Liquid detection circuit

    DOEpatents

    Regan, Thomas O. (North Aurora, IL)

    1987-01-01

    Herein is a circuit which is capable of detecting the presence of liquids, especially cryogenic liquids, and whose sensor will not overheat in a vacuum. The circuit parameters, however, can be adjusted to work with any liquid over a wide range of temperatures.

  1. Supergluing MOF liquid marbles.

    PubMed

    Chin, Jia Min; Reithofer, Michael R; Tan, Tristan Tsai Yuan; Menon, Ajay Govinda; Chen, Eric Yu; Chow, Chin Ann; Hor, Andy Tzi Sum; Xu, Jianwei

    2013-01-18

    Growth of NH(2)-MIL-53(Al) on alumina microparticles followed by post-synthetic modification with perfluorooctyl or caproic groups produces highly hydrophobic microparticles which are utilized for the formation of liquid marbles. Interfacial polymerization of ethyl-2-cyanoacrylate on the surface of the liquid marbles produces stable liquid capsules. PMID:23202539

  2. Renewable liquid reflection grating

    DOEpatents

    Ryutov, Dmitri D.; Toor, Arthur

    2003-10-07

    A renewable liquid reflection grating. Electrodes are operatively connected to a conducting liquid in an arrangement that produces a reflection grating and driven by a current with a resonance frequency. In another embodiment, the electrodes create the grating by a resonant electrostatic force acting on a dielectric liquid.

  3. Industry Support

    NASA Technical Reports Server (NTRS)

    2003-01-01

    NASA Glenn Research Center (GRC) is responsible for the Advanced Communications for Air Traffic Management (AC/ATM) Project, a sub-element task of the Advanced Air Transportation Technologies (AATT) Project of the NASA Aviation System Capacity Program (ASC). The AC/ATM Project is developing new communications technologies and tools that will improve throughput in the U.S. Air Traffic Control System. The goal of the AC/ATM Project is to enable a communications infrastructure providing the capacity, efficiency, and flexibility necessary to realize benefits of the future mature Free-Flight environment. The capabilities and scope of communications technologies needed to accomplish this goal depend on characteristics of the future Free-Flight environment. There are many operational concepts being proposed for a future ATM system to enable user flexibility and efficiency. GRC s focus is on developing new technologies and techniques to support the digital communication of information involving airborne and ground-based users. However, the technologies and techniques must be integrated with the systems and services that industry and the Federal Aviation Administration (FAA) are developing. Thus, GRC needs to monitor and provide input to the various industry and FAA organizations and committees that are specifying new systems and services. Adoption of technologies by the FAA is partially dependent on acceptance of the technology by the aviation community. The commercial aviation community in particular would like to adopt technologies that can be used throughout the world. As a result, the adoption of common or at least compatible technologies by European countries is a key factor in getting commitments to those technologies by the US aviation community. GRC desires to keep informed of European activities that relate to aviation communication technologies, particularly those that are being supported by Eurocontrol.

  4. Forced Oscillations of Supported Drops

    NASA Technical Reports Server (NTRS)

    Wilkes, Edward D.; Basaran, Osman A.

    1996-01-01

    Oscillations of supported liquid drops are the subject of wide scientific interest, with applications in areas as diverse as liquid-liquid extraction, synthesis of ceramic powders, growing of pure crystals in low gravity, and measurement of dynamic surface tension. In this research, axisymmetric forced oscillations of arbitrary amplitude of viscous liquid drops of fixed volume which are pendant from or sessile on a rod with a fixed or moving contact line and surrounded by an inviscid ambient gas are induced by moving the rod in the vertical direction sinusiodally in time. In this paper, a preliminary report is made on the computational analysis of the oscillations of supported drops that have 'clean' interfaces and whose contact lines remain fixed throughout their motions. The relative importance of forcing to damping can be increased by either increasing the amplitude of rod motion A or Reynolds number Re. It is shown that as the ratio of forcing to damping rises, for drops starting from an initial rest state a sharp increase in deformation can occur when they are forced to oscillate in the vicinity of their resonance frequencies, indicating the incipience of hysteresis. However, it is also shown that the existence of a second stable limit cycle and the occurrence of hysteresis can be observed if the drop is subjected to a so-called frequency sweep, where the forcing frequency is first increased and then decreased over a suitable range. Because the change in drop deformation response is abrupt in the vicinity of the forcing frequencies where hysteresis occurs, it should be possible to exploit the phenomenon to accurately measure the viscosity and surface tension of the drop liquid.

  5. Liquid polyamorphism: Possible relation to the anomalous behaviour of water

    NASA Astrophysics Data System (ADS)

    Stanley, H. E.; Kumar, P.; Franzese, G.; Xu, L.; Yan, Z.; Mazza, M. G.; Buldyrev, S. V.; Chen, S.-H.; Mallamace, F.

    2008-07-01

    We present evidence from experiments and computer simulations supporting the hypothesis that water displays polyamorphism, i.e., water separates into two distinct liquid phases. This concept of a new liquid-liquid phase transition is finding application to other liquids as well as water, such as silicon and silica. Specifically, we investigate, the relation between changes in dynamic and thermodynamic anomalies arising from the presence of the liquid-liquid critical point in (i) Two models of water, TIP5P and ST2, which display a first order liquid-liquid phase transition at low temperatures; (ii) the Jagla model, a spherically symmetric two-scale potential known to possess a liquid-liquid critical point, in which the competition between two liquid structures is generated by repulsive and attractive ramp interactions; and (iii) A Hamiltonian model of water where the idea of two length/energy scales is built in. This model also displays a first order liquid-liquid phase transition at low temperatures besides the first order liquid-gas phase transition at high temperatures. We find a correlation between the dynamic fragility crossover and the locus of specific heat maxima CP max (Widom line) emanating from the critical point. Our findings are consistent with a possible relation between the previously hypothesised liquid-liquid phase transition and the transition in the dynamics recently observed in neutron scattering experiments on confined water. More generally, we argue that this connection between CP max and the dynamic crossover is not limited to the case of water, a hydrogen bonded network liquid, but is a more general feature of crossing the Widom line, an extension of the first-order coexistence line in the supercritical region. Dedicated to Armin Bunde on the occasion of his 60th birthday.

  6. Radiation monitor for liquids

    DOEpatents

    Koster, James E. (Los Alamos, NM); Bolton, Richard D. (Los Alamos, NM)

    1999-01-01

    A radiation monitor for use with liquids that utilizes air ions created by alpha radiation emitted by the liquids as its detectable element. A signal plane, held at an electrical potential with respect to ground, collects these air ions. A guard plane or guard rings is used to limit leakage currents. In one embodiment, the monitor is used for monitoring liquids retained in a tank. Other embodiments monitor liquids flowing through a tank, and bodies of liquids, such as ponds, lakes, rivers and oceans.

  7. Radiation monitor for liquids

    DOEpatents

    Koster, J.E.; Bolton, R.D.

    1999-03-02

    A radiation monitor for use with liquids that utilizes air ions created by alpha radiation emitted by the liquids as its detectable element. A signal plane, held at an electrical potential with respect to ground, collects these air ions. A guard plane or guard rings is used to limit leakage currents. In one embodiment, the monitor is used for monitoring liquids retained in a tank. Other embodiments monitor liquids flowing through a tank, and bodies of liquids, such as ponds, lakes, rivers and oceans. 4 figs.

  8. Cosmology with liquid mirror telescopes

    NASA Astrophysics Data System (ADS)

    Hogg, David W.; Gibson, Brad K.; Hickson, Paul

    1993-01-01

    Liquid mirrors provide an exciting means to obtain large optical telescopes for substantially lower costs than conventional technologies. The liquid mirror concept has been demonstrated in the lab with the construction of a diffraction limited 1.5 m mirror. The mirror surface, using liquid mercury, forms a perfect parabolic shape when the mirror cell is rotated at a uniform velocity. A liquid mirror must be able to support a heavy mercury load with minimal flexure and have a fundamental resonant frequency that is as high as possible, to suppress the amplitude of surface waves caused by small vibrations transmitted to the mirror. To minimize the transmission of vibrations to the liquid surface, the entire mirror rests on an air bearing. This necessitates the mirror cell being lightweight, due to the limited load capabilities of the air bearing. The mirror components must also have physical characteristics which minimize the effects of thermal expansion with ambient temperature fluctuations in the observatory. In addition, the 2.7 m mirror construction is designed so that the techniques used may be readily extended to the construction of large mirrors. To attain the goals of a lightweight, rigid mirror, a composite laminant construction was used. The mirror consists of a foam core cut to the desired parabolic shape, with an accuracy of a few mm. An aluminum hub serves as an anchor for the foam and skin, and allows precise centering of the mirror on the air bearing and drive system. Several plys of Kevlar, covered in an epoxy matrix, are then applied to the foam. A final layer of pure epoxy is formed by spin casting. This final layer is parabolic to within a fraction of a mm. An aluminum ring bonded to the circumference of the mirror retains the mercury, and incorporates stainless-steel hard-points for the attachment of balance weights.

  9. Liquid Wall Chambers

    SciTech Connect

    Meier, W R

    2011-02-24

    The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

  10. Liquid Propellant Manipulated Acoustically

    NASA Technical Reports Server (NTRS)

    Oeftering, Richard C.; Chato, David J.; Mann, Adin, III

    2003-01-01

    Fluids are difficult to manage in the space environment. Without gravity, the liquid and gas do not always remain separated as they do in the 1g environment of Earth. Instead the liquid and gas volumes mix and migrate under the influence of surface tension, thermodynamic forces, and external disturbances. As a result, liquid propellants may not be in a useable location or may even form a chaotic mix of liquid and gas bubbles. In the past, mechanical pumps, baffles, and a variety of specialized passive devices have been used to control the liquid and gas volumes. These methods need to be carefully tuned to a specific configuration to be effective. With increasing emphasis on long-term human activity in space there is a trend toward liquid systems that are more flexible and provide greater control. We are exploring new methods of manipulating liquids by using the nonlinear acoustic effects achieved by using beams of highly directed high-intensity acoustic waves.

  11. Coupled-wire construction of chiral spin liquids

    NASA Astrophysics Data System (ADS)

    Meng, Tobias; Neupert, Titus; Greiter, Martin; Thomale, Ronny

    2015-06-01

    We develop a coupled-wire construction of chiral spin liquids. The starting points are individual wires of electrons in the Mott regime that are subject to a Zeeman field and Rashba spin-orbit coupling. Suitable spin-flip couplings between the wires yield an Abelian chiral spin liquid state which supports spinon excitations above a bulk gap and chiral edge states. The approach generalizes to non-Abelian chiral spin liquids at level k with parafermionic edge states.

  12. Liquid/Gas Vortex Separator

    NASA Technical Reports Server (NTRS)

    Morris, B. G.

    1986-01-01

    Liquid/gas separator vents gas from tank of liquid that contains gas randomly distributed in bubbles. Centrifugal force separates liquid and gas, forcing liquid out of vortex tube through venturi tube. Gas vented through exhaust port. When liquid detected in vent tube, exhaust port closed, and liquid/gas mixture in vent tube drawn back into tank through venturi.

  13. Rocking response of tanks containing two liquids

    SciTech Connect

    Tang, Y.

    1995-01-01

    A study on the dynamic response of upright circular cylindrical liquid-storage tanks containing two different liquids under a rocking base motion with an arbitrary temporal variation is presented. Only rigid tanks were studied. The response quantities examined include the hydrodynamic pressure, sloshing wave height and the associated frequencies, base shear and moments. Each of these response quantities is expressed as the sum of the so-called impulsive component and convective component. Unlike the case of tanks containing one liquid, in which the response is controlled by one parameter, height-to-radius ratio, the response of tanks containing two different liquids are controlled by three parameters: height-to-radius ratio, and mass density ratio and height ratio of the two liquids. The interrelationship of the responses of the tank-liquid system to rocking and lateral base excitations is established by examining numerical results extensively. The study shows that some of the response quantities for tank-liquid system under a rocking base motion can be determined from the available data for the response of an identical tank under a horizontal base motion. Base rocking motion can occur in a ground-supported tank or in an elevated tank under earthquake motions.

  14. Liquid-metal-cooled nuclear reactor. [LMFBR

    SciTech Connect

    Robin, M.

    1981-10-20

    A liquid metal cooled nuclear reactor is described which comprises a core, a main vessel comprising a first supporting means, a primary vessel mounted inside said main vessel and coaxial therewith, at least one exchanger outside said vessels. Said primary vessel comprises a core-diagrid and a second supporting means integral with the main vessel lateral wall and with the primary vessel lateral wall. These lateral walls define an annular space in which is formed a horizontal partition.

  15. Liquidliquid phase transition in compressed hydrogen from first-principles simulations

    PubMed Central

    Scandolo, Sandro

    2003-01-01

    The properties of compressed liquid hydrogen, the most abundant fluid in the universe, have been investigated by means of first-principles molecular dynamics at pressures between 75 and 175 GPa and temperatures closer to the freezing line than so far reported in shock-wave experiments. Evidence for a liquidliquid transition between a molecular and a dissociated phase is provided. The transition is accompanied by a 6% increase in density and by metallization. This finding has important implications for our understanding of the interiors of giant planets and supports predictions of a quantum fluid state at low temperatures. PMID:12626753

  16. Bubbling in unbounded coflowing liquids.

    PubMed

    Gañán-Calvo, Alfonso M; Herrada, Miguel A; Garstecki, Piotr

    2006-03-31

    An investigation of the stability of low density and viscosity fluid jets and spouts in unbounded coflowing liquids is presented. A full parametrical analysis from low to high Weber and Reynolds numbers shows that the presence of any fluid of finite density and viscosity inside the hollow jet elicits a transition from an absolute to a convective instability at a finite value of the Weber number, for any value of the Reynolds number. Below that critical value of the Weber number, the absolute character of the instability leads to local breakup, and consequently to local bubbling. Experimental data support our model. PMID:16605912

  17. Mobile impurities in ferromagnetic liquids

    NASA Astrophysics Data System (ADS)

    Kantian, Adrian; Schollwoeck, Ulrich; Giamarchi, Thierry

    2011-03-01

    Recent work has shown that mobile impurities in one dimensional interacting systems may exhibit behaviour that differs strongly from that predicted by standard Tomonaga-Luttinger liquid theory, with the appearance of power-law divergences in the spectral function signifying sublinear diffusion of the impurity. Using time-dependent matrix product states, we investigate a range of cases of mobile impurities in systems beyond the analytically accessible examples to assess the existence of a new universality class of low-energy physics in one-dimensional systems. Correspondence: Adrian.Kantian@unige.ch This work was supported in part by the Swiss SNF under MaNEP and division II.

  18. Surface orientation in ionic liquids

    NASA Astrophysics Data System (ADS)

    Law, George; Watson, Philip R.

    2001-09-01

    New surface tension data supports models of surface orientations previously derived from direct recoil spectrometry (DRS) data for the cations of 1-alkyl-3-methylimidazolium ionic liquids. For shorter-chain hexafluorophosphate compounds the favored average orientation appears to be one where the cation is oriented vertically with the N atoms uppermost, but the alkyl substituents do not protrude out of the surface. For longer chains or for compounds containing the smaller tetrafluoroborate anion the surface tension and DRS data are consistent with a shift to an average orientation embodying a rotation that moves the methyl group towards the surface.

  19. Charged clusters in liquid helium

    NASA Astrophysics Data System (ADS)

    Dyugaev, A. M.; Grigor'ev, P. D.; Lebedeva, E. V.

    2010-03-01

    The appropriateness of the experimental study of charged clusters in liquid helium has been supported. The interaction potential of negative ions (electron bubbles) with inert clusters formed by Ne, Ar, Kr, and Xe atoms or H2 and N2 molecules has been found. Small clusters levitate at a distance of 13-16 above the negative ion. The scalings laws for the properties of charged inert clusters have been discovered and grounded; the number of quantum levels and states of such clusters has been determined. The mobility measurement of charged clusters may provide a new technique of probing the properties of impurity nanoparticles in helium.

  20. Performance after weathering of a liquid solar collector

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Results from retesting of liquid solar collector described in "Performance evaluation of liquid collector" (M-FS-23931), after long term exposure to natural weathering indicate no detectable degradation in collector performance and no visable deterioration in appearance of collector. Supporting data and pretest/post test efficiency comparison are included.

  1. Monogroove liquid heat exchanger

    NASA Technical Reports Server (NTRS)

    Brown, Richard F. (Inventor); Edelstein, Fred (Inventor)

    1990-01-01

    A liquid supply control is disclosed for a heat transfer system which transports heat by liquid-vapor phase change of a working fluid. An assembly (10) of monogroove heat pipe legs (15) can be operated automatically as either heat acquisition devices or heat discharge sources. The liquid channels (27) of the heat pipe legs (15) are connected to a reservoir (35) which is filled and drained by respective filling and draining valves (30, 32). Information from liquid level sensors (50, 51) on the reservoir (35) is combined (60) with temperature information (55) from the liquid heat exchanger (12) and temperature information (56) from the assembly vapor conduit (42) to regulate filling and draining of the reservoir (35), so that the reservoir (35) in turn serves the liquid supply/drain needs of the heat pipe legs (15), on demand, by passive capillary action (20, 28).

  2. Enhancing liquid jet erosion

    SciTech Connect

    Johnson V.E. Jr.

    1984-10-02

    Process and apparatus for enhancing the erosive intensity of a high velocity liquid jet when the jet is impacted against a surface for cutting, cleaning, drilling or otherwise acting on the surface. A preferred method comprises the steps of forming a high velocity liquid jet, oscillating the velocity of the jet at a preferred Strouhal number, and impinging the pulsed jet against a solid surface to be eroded. Typically the liquid jet is pulsed by oscillating the velocity of the jet mechanically or by hydrodynamic and acoustic interactions. The invention may be applied to enhance cavitation erosion in a cavitating liquid jet, or to modulate the velocity of a liquid jet, or to modulate the velocity of a liquid jet exiting in a gas, causing it to form into discrete slugs, thereby producing an intermittent percussive effect.

  3. Liquid level detector

    DOEpatents

    Tshishiku, Eugene M. (Augusta, GA)

    2011-08-09

    A liquid level detector for conductive liquids for vertical installation in a tank, the detector having a probe positioned within a sheath and insulated therefrom by a seal so that the tip of the probe extends proximate to but not below the lower end of the sheath, the lower end terminating in a rim that is provided with notches, said lower end being tapered, the taper and notches preventing debris collection and bubble formation, said lower end when contacting liquid as it rises will form an airtight cavity defined by the liquid, the interior sheath wall, and the seal, the compression of air in the cavity preventing liquid from further entry into the sheath and contact with the seal. As a result, the liquid cannot deposit a film to form an electrical bridge across the seal.

  4. Arsenic removal by liquid membranes.

    PubMed

    Marino, Tiziana; Figoli, Alberto

    2015-01-01

    Water contamination with harmful arsenic compounds represents one of the most serious calamities of the last two centuries. Natural occurrence of the toxic metal has been revealed recently for 21 countries worldwide; the risk of arsenic intoxication is particularly high in Bangladesh and India but recently also Europe is facing similar problem. Liquid membranes (LMs) look like a promising alternative to the existing removal processes, showing numerous advantages in terms of energy consumption, efficiency, selectivity, and operational costs. The development of different LM configurations has been a matter of investigation by several researching groups, especially for the removal of As(III) and As(V) from aqueous solutions. Most of these LM systems are based on the use of phosphine oxides as carriers, when the metal removal is from sulfuric acid media. Particularly promising for water treatment is the hollow fiber supported liquid membrane (HFSLM) configuration, which offers high selectivity, easy transport of the targeted metal ions, large surface area, and non-stop flow process. The choice of organic extractant(s) plays an essential role in the efficiency of the arsenic removal. Emulsion liquid membrane (ELM) systems have not been extensively investigated so far, although encouraging results have started to appear in the literature. For such LM configuration, the most relevant step toward efficiency is the choice of the surfactant type and its concentration. PMID:25826756

  5. Liquid Effluents Program mission analysis

    SciTech Connect

    Lowe, S.S.

    1994-09-27

    Systems engineering is being used to identify work to cleanup the Hanford Site. The systems engineering process transforms an identified mission need into a set of performance parameters and a preferred system configuration. Mission analysis is the first step in the process. Mission analysis supports early decision-making by clearly defining the program objectives, and evaluating the feasibility and risks associated with achieving those objectives. The results of the mission analysis provide a consistent basis for subsequent systems engineering work. A mission analysis was performed earlier for the overall Hanford Site. This work was continued by a ``capstone`` team which developed a top-level functional analysis. Continuing in a top-down manner, systems engineering is now being applied at the program and project levels. A mission analysis was conducted for the Liquid Effluents Program. The results are described herein. This report identifies the initial conditions and acceptable final conditions, defines the programmatic and physical interfaces and sources of constraints, estimates the resources to carry out the mission, and establishes measures of success. The mission analysis reflects current program planning for the Liquid Effluents Program as described in Liquid Effluents FY 1995 Multi-Year Program Plan.

  6. Arsenic Removal by Liquid Membranes

    PubMed Central

    Marino, Tiziana; Figoli, Alberto

    2015-01-01

    Water contamination with harmful arsenic compounds represents one of the most serious calamities of the last two centuries. Natural occurrence of the toxic metal has been revealed recently for 21 countries worldwide; the risk of arsenic intoxication is particularly high in Bangladesh and India but recently also Europe is facing similar problem. Liquid membranes (LMs) look like a promising alternative to the existing removal processes, showing numerous advantages in terms of energy consumption, efficiency, selectivity, and operational costs. The development of different LM configurations has been a matter of investigation by several researching groups, especially for the removal of As(III) and As(V) from aqueous solutions. Most of these LM systems are based on the use of phosphine oxides as carriers, when the metal removal is from sulfuric acid media. Particularly promising for water treatment is the hollow fiber supported liquid membrane (HFSLM) configuration, which offers high selectivity, easy transport of the targeted metal ions, large surface area, and non-stop flow process. The choice of organic extractant(s) plays an essential role in the efficiency of the arsenic removal. Emulsion liquid membrane (ELM) systems have not been extensively investigated so far, although encouraging results have started to appear in the literature. For such LM configuration, the most relevant step toward efficiency is the choice of the surfactant type and its concentration. PMID:25826756

  7. Swimming bacteria in liquid crystal

    NASA Astrophysics Data System (ADS)

    Sokolov, Andrey; Zhou, Shuang; Aranson, Igor; Lavrentovich, Oleg

    2014-03-01

    Dynamics of swimming bacteria can be very complex due to the interaction between the bacteria and the fluid, especially when the suspending fluid is non-Newtonian. Placement of swimming bacteria in lyotropic liquid crystal produces a new class of active materials by combining features of two seemingly incompatible constituents: self-propelled live bacteria and ordered liquid crystals. Here we present fundamentally new phenomena caused by the coupling between direction of bacterial swimming, bacteria-triggered flows and director orientations. Locomotion of bacteria may locally reduce the degree of order in liquid crystal or even trigger nematic-isotropic phase transition. Microscopic flows generated by bacterial flagella disturb director orientation. Emerged birefringence patterns allow direct optical observation and quantitative characterization of flagella dynamics. At high concentration of bacteria we observed the emergence of self-organized periodic texture caused by bacteria swimming. Our work sheds new light on self-organization in hybrid bio-mechanical systems and can lead to valuable biomedical applications. Was supported by the US DOE, Office of Basic Energy Sciences, Division of Materials Science and Engineering, under the Contract No. DE AC02-06CH11357.

  8. Liquid sheet radiator apparatus

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L. (Inventor)

    1990-01-01

    An external flow, liquid sheet radiator apparatus adapted for space applications has as its radiating surface a thin stable liquid sheet formed by fluid flow through a very narrow slit affixed to the sheet generator. As a result of surface tension forces, the sheet has a triangular shape and is collected into a simply designed collector positioned at the apex of the triangle. The specific power for the liquid sheet is virtually the same as the droplet sheet specific power.

  9. 49 CFR 195.208 - Welding of supports and braces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Welding of supports and braces. 195.208 Section 195.208 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS... HAZARDOUS LIQUIDS BY PIPELINE Construction § 195.208 Welding of supports and braces. Supports or braces...

  10. 49 CFR 195.208 - Welding of supports and braces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Welding of supports and braces. 195.208 Section 195.208 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS... HAZARDOUS LIQUIDS BY PIPELINE Construction § 195.208 Welding of supports and braces. Supports or braces...

  11. 49 CFR 195.208 - Welding of supports and braces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Welding of supports and braces. 195.208 Section 195.208 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS... HAZARDOUS LIQUIDS BY PIPELINE Construction § 195.208 Welding of supports and braces. Supports or braces...

  12. 49 CFR 195.208 - Welding of supports and braces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Welding of supports and braces. 195.208 Section 195.208 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS... HAZARDOUS LIQUIDS BY PIPELINE Construction § 195.208 Welding of supports and braces. Supports or braces...

  13. 49 CFR 195.208 - Welding of supports and braces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Welding of supports and braces. 195.208 Section 195.208 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS... HAZARDOUS LIQUIDS BY PIPELINE Construction § 195.208 Welding of supports and braces. Supports or braces...

  14. Heat exchanger support apparatus in a fluidized bed

    DOEpatents

    Lawton, Carl W. (West Hartford, CT)

    1982-01-01

    A heat exchanger is mounted in the upper portion of a fluidized combusting bed for the control of the temperature of the bed. A support, made up of tubes, is extended from the perforated plate of the fluidized bed up to the heat exchanger. The tubular support framework for the heat exchanger has liquid circulated therethrough to prevent deterioration of the support.

  15. Liquid Crystal Optofluidics

    SciTech Connect

    Vasdekis, Andreas E.; Cuennet, J. G.; Psaltis, D.

    2012-10-11

    By employing anisotropic fluids and namely liquid crystals, fluid flow becomes an additional degree of freedom in designing optofluidic devices. In this paper, we demonstrate optofluidic liquid crystal devices based on the direct flow of nematic liquid crystals in microfluidic channels. Contrary to previous reports, in the present embodiment we employ the effective phase delay acquired by light travelling through flowing liquid crystal, without analysing the polarisation state of the transmitted light. With this method, we demonstrate the variation in the diffraction pattern of an array of microfluidic channels acting as a grating. We also discuss our recent activities in integrating mechanical oscillators for on-chip peristaltic pumping.

  16. Liquid level detector

    DOEpatents

    Tokarz, Richard D. (West Richland, WA)

    1982-01-01

    A liquid level sensor having a pair of upright conductors spaced by an insulator defining a first high resistance path between the conductors. An electrically conductive path is interposed between the upright conductors at a discrete location at which liquid level is to be measured. It includes a liquid accessible gap of a dimension such that the electrical resistance across the conductor when the gap is filled with the liquid is detectably less than when the gap is emptied. The conductor might also be physically altered by temperature changes to serve also as an indicator of elevated temperature.

  17. Ultrasonic liquid level detector

    DOEpatents

    Kotz, Dennis M. (North Augusta, SC); Hinz, William R. (Augusta, GA)

    2010-09-28

    An ultrasonic liquid level detector for use within a shielded container, the detector being tubular in shape with a chamber at its lower end into which liquid from in the container may enter and exit, the chamber having an ultrasonic transmitter and receiver in its top wall and a reflector plate or target as its bottom wall whereby when liquid fills the chamber a complete medium is then present through which an ultrasonic wave may be transmitted and reflected from the target thus signaling that the liquid is at chamber level.

  18. PREFACE: 6th Liquid Matter Conference

    NASA Astrophysics Data System (ADS)

    Dijkstra, Marjolein; van Roij, René; Vroege, Gert Jan; Lekkerkerker, Henk; Frenkel, Daan

    2005-11-01

    This special issue of Journal of Physics: Condensed Matter contains the Proceedings of the 6th Liquid Matter Conference held in Utrecht, The Netherlands, 2-6 July 2005. The three-yearly Liquid Matter Conference is organized by the Liquids Section of the Condensed Matter Division of the European Physical Society. This series of meetings began in Lyon in 1990. The most recent meeting was held in 2003 in Konstanz. The aim of the Liquid Matter Conferences is to bring together scientists working on the liquid state of matter. This rapidly growing field includes the physics, chemistry, biology and chemical engineering of liquid matter as well as various applied research areas. In fact, the Utrecht meeting had, for the first time, a special session devoted to Fundamental Challenges in Applied Liquid Physics and Microfluidics. The Utrecht meeting had 760 registered participants from four continents. An important event at this meeting was the award of the First Liquid Matter Prize of the European Physical Society to Professor Jean-Pierre Hansen FRS, of Cambridge University. In addition to a plenary speech by the recipient of the Liquid Matter Prize, the scientific programme consisted of 10 plenary lectures, 117 symposia talks, 25 of which were keynote lectures and some 650 poster contributions. The meeting also hosted a one-day symposium of the Division of Liquids and Interfaces of the Chemical Sciences division of NWO. This special issue of Journal of Physics: Condensed Matter contains 61 of the oral communications. Liquid state physics is at the interface of many fields of research. As a consequence, many of the attendants come from adjacent fields and find in the Liquid Matter Conference a forum to meet experts from other areas of research. This aspect of the Liquid Matter Conference makes it an exciting meeting as it not only offers the participants an up-to-date picture of the status of research into the liquid state of matter, but it also allows them to establish new (and often unexpected) trans-disciplinary contacts for joint scientific endeavours. This applies in particular to the area of soft condensed matter such as colloidal suspensions, polymeric systems and biological materials. The conference was held at the Uithof, the campus of the University of Utrecht. The organizers gratefully acknowledge the generosity of the University and City of Utrecht, which enabled us to stage both the scientific part of the conference and several festive and cultural events in some of the most attractive venues of the Netherlands. We were also delighted by the substantial contributions offered by the sponsors of the 6th Liquid Matter Conference. With this support it became possible to support a large number of scientists who would otherwise not have been able to attend. Finally, we owe a great debt of gratitude to the secretarial staff of the conference and the many students, postdocs and other colleagues who helped tirelessly (and very efficiently) to make the conference run smoothly. The Board of the Liquids Section of the European Physical Society decided that the 7th Liquid Matter Conference will be held in Lund (Sweden). The tentative dates are Friday 27 June 2008 to Tuesday 1 July 2008.

  19. Thrust vector control by liquid injection for solid propellant rockets

    NASA Technical Reports Server (NTRS)

    Zeamer, R. J.

    1975-01-01

    In liquid injection thrust vector control, a rocket jet is deflected for steering purposed by injecting a liquid into the nozzle exit cone. The liquid is preferably both dense and reactive so that it adds mass and energy and generates shocks in the supersonic exhaust. This behavior increases thrust in the affected part of the jet producing not only a side force for steering but an addition to axial thrust. This paper presents a summary of current liquid injection thrust vector control technology, including procedures for design, development, analysis, testing and evaluation, together with supporting data and references.

  20. Free vibration analysis of partially filled liquid storage tanks

    SciTech Connect

    Tang, Yu; Chang, Y.W.

    1993-05-01

    A study on the free vibration analysis of partially filled liquid storage tanks is presented. The tanks considered are the upright circular cylindrical tanks that are rigidly supported at the base. The top of the tanks are either free or constrained. Two types of constraints are considered, namely, hinged and roller support. The governing differential equations for the tank-liquid system are obtained by application of the Rayleigh-Ritz procedure in combination with Lagrange`s equation. The response functions examined include the frequency of the fundamental mode of vibration of the tank-liquid system and the associated modal pressure.

  1. Acoustic excitation and destruction of liquid sheets

    NASA Astrophysics Data System (ADS)

    Rhys, Noah Oliver

    Flat sheets and swirl coaxial liquid sheets are investigated experimentally while under conditions similar to those present in an unstable liquid rocket engine combustor. Both spray geometries were found to respond to the imposed acoustic field. Photographs show that the flat sheet can be driven to Support waves at acoustic frequencies between 1700 Hertz and 600 Hertz at both the pressure and velocity antinodes. For a fixed acoustic decibel level, the amplitude of the waves on the flat sheet increased as the acoustic driving frequency was decreased. The sheet showed a natural shedding frequency of 900 Hertz. A light scattering experiment was validated using the flat sheet as a test article. Photographs of the swirl coaxial sheet showed no discernible structural change under the imposed acoustic field, but the light scattering experiments showed that the swirl coaxial sheets did respond to the acoustic energy. Fast Fourier transforms of the light scattering data showed that the swirl coaxial sheets were driven to shed ligaments at the frequency of the imposed acoustic field. As coaxial air velocity increased, the swirl coaxial sheet responded more readily to higher frequency acoustics and less readily to lower frequencies. This is in keeping with earlier analytical work found in literature. Contrary to expectation, no difference in the size of droplets was measured by a phase Doppler particle analyzer when the spray was acoustically driven. This work supports the theory that liquid rocket engines are less susceptible to combustion instability if the injected spray is directly atomized by strong aerodynamic forces. In such a case, the liquid sheet is torn apart before surface waves can be formed. The spray resulting from liquid/liquid impinging injector elements forms a liquid sheet, and such injectors have historically been unstable.

  2. Evidence for Liquid Water on Comets

    NASA Technical Reports Server (NTRS)

    Sheldon, Robert; Hoover, Richard

    2005-01-01

    We have reexamined the arguments for the existence of liquid water on comets, and believe that recent cometary flybys along with pre-Giotto data support its presence on short-period comets. Liquid water would affect cometary dynamics, leaving distinct signatures in precession, orbital dynamics, and potential splitting of comets. Liquid water geysers would affect cometary atmosphere, dust evolution, and non-gravitational forces that perturb the orbit. Liquid water would affect the composition of both the interior and exterior of the comet, producing geologic effects consistent with recent flyby photographs. And most importantly, liquid water suppork the growth of lifeforms, which would make a comet a biofriendly incubator for interplanetary transport. The major objection against liquid water is the necessity of a pressure vessel to prevent sublimation into space. We discuss how such a pressure vessel could naturally evolve as a pristine comet makes its first journey inside the orbit of Mars, and suggest that this type of vessel was observed by Giotto, Deep Space I, and Stardust.

  3. Synthesis of ionic liquids

    DOEpatents

    Dai, Sheng [Knoxville, TN; Luo, Huimin [Knoxville, TN

    2008-09-09

    Ionic compounds which are liquids at room temperature are formed by the method of mixing a neutral organic liqand with the salt of a metal cation and its conjugate anion. The liquids are hydrophobic, conductive and stable and have uses as solvents and in electrochemical devices.

  4. Synthesis of ionic liquids

    DOEpatents

    Dai, Sheng (Knoxville, TN); Luo, Huimin (Knoxville, TN)

    2011-11-01

    Ionic compounds which are liquids at room temperature are formed by the method of mixing a neutral organic ligand with the salt of a metal cation and its conjugate anion. The liquids are hydrophobic, conductive and stable and have uses as solvents and in electrochemical devices.

  5. Liquid Chromatography in 1982.

    ERIC Educational Resources Information Center

    Freeman, David H.

    1982-01-01

    Reviews trends in liquid chromatography including apparatus, factors affecting efficient separation of a mixture (peak sharpness and speed), simplified problem-solving, adsorption, bonded phase chromatography, ion selectivity, and size exclusion. The current trend is to control chemical selectivity by the liquid phase. (Author/JN)

  6. Precision liquid level sensor

    DOEpatents

    Field, Michael E. (Albuquerque, NM); Sullivan, William H. (Albuquerque, NM)

    1985-01-01

    A precision liquid level sensor utilizes a balanced R. F. bridge, each arm including an air dielectric line. Changes in liquid level along one air dielectric line imbalance the bridge and create a voltage which is directly measurable across the bridge.

  7. Advanced proteomic liquid chromatography

    SciTech Connect

    Xie, Fang; Smith, Richard D.; Shen, Yufeng

    2012-10-26

    Liquid chromatography coupled with mass spectrometry is the predominant platform used to analyze proteomics samples consisting of large numbers of proteins and their proteolytic products (e.g., truncated polypeptides) and spanning a wide range of relative concentrations. This review provides an overview of advanced capillary liquid chromatography techniques and methodologies that greatly improve separation resolving power and proteomics analysis coverage, sensitivity, and throughput.

  8. Liquid heat capacity lasers

    DOEpatents

    Comaskey, Brian J. (Walnut Creek, CA); Scheibner, Karl F. (Tracy, CA); Ault, Earl R. (Livermore, CA)

    2007-05-01

    The heat capacity laser concept is extended to systems in which the heat capacity lasing media is a liquid. The laser active liquid is circulated from a reservoir (where the bulk of the media and hence waste heat resides) through a channel so configured for both optical pumping of the media for gain and for light amplification from the resulting gain.

  9. Experimenting with Liquid Membranes.

    ERIC Educational Resources Information Center

    Lamb, J. D.; And Others

    1980-01-01

    Outlined are two experiments using liquid membranes that illustrate carrier-facilitated transport, where chemical species are ushered across the membrane by selective "carrier" molecules residing in the membrane. The use of liquid membranes as models for studying and describing biological transport mechanisms is explored. (CS)

  10. Precision liquid level sensor

    DOEpatents

    Field, M.E.; Sullivan, W.H.

    1985-01-29

    A precision liquid level sensor utilizes a balanced R. F. bridge, each arm including an air dielectric line. Changes in liquid level along one air dielectric line imbalance the bridge and create a voltage which is directly measurable across the bridge. 2 figs.

  11. INEEL Liquid Effluent Inventory

    SciTech Connect

    Major, C.A.

    1997-06-01

    The INEEL contractors and their associated facilities are required to identify all liquid effluent discharges that may impact the environment at the INEEL. This liquid effluent information is then placed in the Liquid Effluent Inventory (LEI) database, which is maintained by the INEEL prime contractor. The purpose of the LEI is to identify and maintain a current listing of all liquid effluent discharge points and to identify which discharges are subject to federal, state, or local permitting or reporting requirements and DOE order requirements. Initial characterization, which represents most of the INEEL liquid effluents, has been performed, and additional characterization may be required in the future to meet regulations. LEI information is made available to persons responsible for or concerned with INEEL compliance with liquid effluent permitting or reporting requirements, such as the National Pollutant Discharge Elimination System, Wastewater Land Application, Storm Water Pollution Prevention, Spill Prevention Control and Countermeasures, and Industrial Wastewater Pretreatment. The State of Idaho Environmental Oversight and Monitoring Program also needs the information for tracking liquid effluent discharges at the INEEL. The information provides a baseline from which future liquid discharges can be identified, characterized, and regulated, if appropriate. The review covered new and removed buildings/structures, buildings/structures which most likely had new, relocated, or removed LEI discharge points, and at least 10% of the remaining discharge points.

  12. Column Liquid Chromatography.

    ERIC Educational Resources Information Center

    Majors, Ronald E.; And Others

    1984-01-01

    Reviews literature covering developments of column liquid chromatography during 1982-83. Areas considered include: books and reviews; general theory; columns; instrumentation; detectors; automation and data handling; multidimensional chromatographic and column switching techniques; liquid-solid chromatography; normal bonded-phase, reversed-phase,

  13. LIGHT NONAQUEOUS PHASE LIQUIDS

    EPA Science Inventory

    Nonaqueous phase liquids (NAPLS) are hydrocarbons that exist as a separate, immiscible phase when in contact with water and/or air. ifferences in the physical and chemical properties of water and NAPL result in the formation of a physical interface between the liquids which preve...

  14. Chiral separation by enantioselective liquid-liquid extraction.

    PubMed

    Schuur, Boelo; Verkuijl, Bastiaan J V; Minnaard, Adriaan J; de Vries, Johannes G; Heeres, Hero J; Feringa, Ben L

    2011-01-01

    The literature on enantioselective liquid-liquid extraction (ELLE) spans more than half a century of research. Nonetheless, a comprehensive overview has not appeared during the past few decades. Enantioselective liquid-liquid extraction is a technology of interest for a wide range of chemists and chemical engineers in the fields of fine chemicals, pharmaceuticals, agrochemicals, fragrances and foods. In this review the principles and advances of resolution through enantioselective liquid-liquid extraction are discussed, starting with an introduction on the principles of enantioselective liquid-liquid extraction including host-guest chemistry, extraction and phase transfer mechanisms, and multistage liquid-liquid extraction processing. Then the literature on enantioselective liquid-liquid extraction systems is reviewed, structured on extractant classes. The following extractant classes are considered: crown ether based extractants, metal complexes and metalloids, extractants based on tartrates, and a final section with all other types of chiral extractants. PMID:21107491

  15. Fluorinated monolayers at liquid-liquid and liquid-vapor interfaces

    NASA Astrophysics Data System (ADS)

    Zhang, Zhongjian

    Microscopic structure of several fluorinated monolayers at water-vapor and water-oil interfaces were examined using x-ray specular reflectivity and grazing incidence diffraction (GID) techniques. Grazing incidence x-ray diffraction measurements of monolayers of perfluoro-n-eicosane (F(CFsb2)sb{20}F) and F(CFsb2)sb{m}(CHsb2)sb{n}H (denoted as Fsb{m}Hsb{n}) supported at the air-water interface demonstrated that even without the conventional polar head group, the surfactant molecules are capable of forming ordered in-plane structures defined by hexagonal close packing of the fluorinated blocks of adsorbed molecules due to the stronger chain-chain interaction between fluorocarbon chains than the corresponding hydrocarbons. The specular reflectivity data reveals a hydrocarbon-down, fluorocarbon-up orientation for Fsb{12}Hsb{18}. In contrast to the conventional expectation that soluble surfactants form disordered monolayers at the liquid-liquid interface, the studies on a fluoroalcohol (F(CFsb2)sb{10}(CHsb2)sb2OH) monolayer at water-hexane interface indicate that the surfactants are in a close packed hexagonal phase, similar to the in-plane structure of other fluorocarbon molecules at water-air interface. Above a transition temperature the monolayer is in a low density gas phase. Preliminary study shows that hysteresis effect occurs around the transition temperature. The first measurements of microscopic structure at common high interfacial tension liquid-liquid interfaces such as a simple oil-water (hexane-water) interface is also reported. Thermal expansion coefficient measurements indicate subtle structural differences in these monolayers.

  16. Liquid metal enabled pump

    PubMed Central

    Tang, Shi-Yang; Khoshmanesh, Khashayar; Sivan, Vijay; Petersen, Phred; OMullane, Anthony P.; Abbott, Derek; Mitchell, Arnan; Kalantar-zadeh, Kourosh

    2014-01-01

    Small-scale pumps will be the heartbeat of many future micro/nanoscale platforms. However, the integration of small-scale pumps is presently hampered by limited flow rate with respect to the input power, and their rather complicated fabrication processes. These issues arise as many conventional pumping effects require intricate moving elements. Here, we demonstrate a system that we call the liquid metal enabled pump, for driving a range of liquids without mechanical moving parts, upon the application of modest electric field. This pump incorporates a droplet of liquid metal, which induces liquid flow at high flow rates, yet with exceptionally low power consumption by electrowetting/deelectrowetting at the metal surface. We present theory explaining this pumping mechanism and show that the operation is fundamentally different from other existing pumps. The presented liquid metal enabled pump is both efficient and simple, and thus has the potential to fundamentally advance the field of microfluidics. PMID:24550485

  17. Rotor-Liquid-Fundament System's Oscillation

    NASA Astrophysics Data System (ADS)

    Kydyrbekuly, A.

    The work is devoted to research of oscillation and sustainability of stationary twirl of vertical flexible static dynamically out-of-balance rotor with cavity partly filled with liquid and set on relative frame fundament. The accounting of such factors like oscillation of fundament, liquid oscillation, influence of asymmetry of installation of a rotor on a shaft, anisotropism of shaft support and fundament, static and dynamic out-of-balance of a rotor, an external friction, an internal friction of a shaft, allows to settle an invoice more precisely kinematic and dynamic characteristics of system.

  18. Liquid detection trial with x-ray diffraction

    NASA Astrophysics Data System (ADS)

    Harding, G.; Fleckenstein, H.; Olesinski, S.; Zienert, G.

    2010-08-01

    SALOME (an acronym for Small Angle Lab Operation Measuring Equipment) is a versatile, energy-dispersive x-ray diffraction imaging (XDi) test-bed facility commissioned and supported by the Transportation Security Laboratory, Atlantic City, USA. In work presented here, the Inverse Fan-beam (IFB) topology has been realized on SALOME and used to investigate the liquids identification capability of x-ray diffraction (XRD). Liquids were investigated from four classes of materials of relevance to security screening of aircraft passenger luggage; namely: dilute aqueous liquids; concentrated aqueous liquids; hydrocarbon fuels; and oxidizers. A set of features associated with the Molecular Interference Function (MIF) were used to classify the liquids. Within the limited scope of this investigation, XRD proved to have excellent capability for discriminating liquids from one another; in particular, for isolating the threat materials without raising false alarms from either household or innocuous substances. Consequences for XRD-based screening of air passenger luggage are summarized.

  19. Ionic conductivity of imidazole-functionalized liquid crystal mesogens

    NASA Astrophysics Data System (ADS)

    Roddecha, Supacharee; Anthamatten, Mitchell

    2012-02-01

    Imidazole has been investigated as a novel anhydrous proton conducting functional group that could enable higher temperature operation (> 120 ^oC) of polymer electrolyte fuel cells. Its amphoteric behavior can support Grotthuss-like proton transport; however molecular mobility and a high concentration of imidazole groups are needed to achieve high ionic conductivity. Our hypothesis is that liquid crystal ordering, particularly in layered smectic phase, can facilitate formation of 2D proton transport and promote proton conductivity. We have designed and synthesized two imidazole-terminated liquid crystal mesogens, and the ionic conductivities in the liquid crystalline and isotropic states have been measured. Here we report on synthesis and characterization of diacylhydrazine liquid crystals bearing imidazole terminal groups. The proton conductivity of products is compared to pure liquid imidazole and to liquid crystal mesogens without imidazole groups.

  20. Pulsating-gliding transition in the dynamics of levitating liquid nitorgen droplets.

    SciTech Connect

    Snezhko, A.; Jacob, E. B.; Aranson, I. S.; Materials Science Division; Tel-Aviv Univ.

    2008-04-21

    Hot surfaces can cause levitation of small liquid droplets if the temperature is kept above the Leidenfrost point (220 C for water) due to the pressure formed because of rapid evaporation. Here, we demonstrate a new class of pulsating-gliding dynamic transitions in a special setting of the Leidenfrost effect at room temperatures and above a viscous fluid for droplets of liquid nitrogen. A whole range of highly dynamic patterns unfolds when droplets of liquid nitrogen are poured on the surface of another, more viscous liquid at room temperature. We also discovered that the levitating droplets induce vortex motion in the supporting viscous liquid. Depending on the viscosity of the supporting liquid, the nitrogen droplets either adopt an oscillating (pulsating) star-like shape with different azimuthal symmetries (from 2-9 petals) or glide on the surface with random trajectories. Thus, by varying the viscosity of the supporting liquid, we achieve controlled morphology and dynamics of Leidenfrost droplets.

  1. Renewable liquid reflecting zone plate

    DOEpatents

    Toor, Arthur; Ryutov, Dmitri D.

    2003-12-09

    A renewable liquid reflecting zone plate. Electrodes are operatively connected to a dielectric liquid in a circular or other arrangement to produce a reflecting zone plate. A system for renewing the liquid uses a penetrable substrate.

  2. Dynamical and structural heterogeneities close to liquid-liquid phase transitions: The case of gallium

    NASA Astrophysics Data System (ADS)

    Antonelli, Alex; Cajahuaringa, Samuel; de Koning, Maurice

    2013-03-01

    Liquid-liquid phase transitions (LLPT) have been proposed in order to explain the thermodynamic anomalies exhibited by some liquids. Recently, it was found, through molecular dynamics simulations, that liquid elemental gallium, described by a modified embedded-atom model, exhibits a LLPT between a high-density liquid (HDL) and a low-density liquid (LDL), about 60 K below the melting temperature. In this work, we studied the dynamics of supercooled liquid gallium close to the LLPT. Our results show a large increase in the plateau of the self-intermediate scattering function (β-relaxation process) and in the non-Gaussian parameter, indicating a pronounced dynamical heterogeneity upon the onset of the LLPT. The dynamical heterogeneity of the LDL is closely correlated to its structural heterogeneity, since the fast diffusing atoms belong to high-density domains of predominantly 9-fold coordinated atoms, whereas the slow diffusing ones are mostly in low-density domains of 8-fold coordinated atoms. The energetics suggests that the reason for the sluggish dynamics of LDL is due to its larger cohesive energy as compared to that of the HDL. Work supported by FAPESP, CNPq, CAPES, and FAEPEX/UNICAMP

  3. Consolidated incineration facility technical support

    SciTech Connect

    Burns, D.; Looper, M.G.

    1993-12-31

    In 1996, the Savannah River Site plans to begin operation of the Consolidated Incineration Facility (CIF) to treat solid and liquid RCRA hazardous and mixed wastes. The Savannah River Technology Center (SRTC) leads an extensive technical support program designed to obtain incinerator and air pollution control equipment performance data to support facility start-up and operation. Key components of this technical support program include recently completed waste burn tests at both EPA`s Incineration Research Facility and at Energy and Environmental Research Corporation`s Solid Waste Incineration Test Facility. The main objectives for these tests were determining the fate of heavy metals, measuring organics destruction and removal efficiencies, and quantifying incinerator offgas particulate loading and size distribution as a function of waste feed characteristics and incineration conditions. In addition to these waste burning tests, the SRTC has recently completed installations of the Offgas Components Test Facility (OCTF), a 1/10 scale CIF offgas system pilot plant. This pilot facility will be used to demonstrate system operability and maintainability, evaluate and optimize equipment and instrument performance, and provide direct CIF start-up support. Technical support programs of this type are needed to resolve technical issues related with treatment and disposal of combustible hazardous, mixed, and low-level radioactive waste. Implementation of this program will minimize facility start-up problems and help insure compliance with all facility performance requirements.

  4. Noncavitating Pump For Liquid Helium

    NASA Technical Reports Server (NTRS)

    Hasenbein, Robert; Izenson, Michael; Swift, Walter; Sixsmith, Herbert

    1996-01-01

    Immersion pump features high efficiency in cryogenic service. Simple and reliable centrifugal pump transfers liquid helium with mass-transfer efficiency of 99 percent. Liquid helium drawn into pump by helical inducer, which pressurizes helium slightly to prevent cavitation when liquid enters impeller. Impeller then pressurizes liquid. Purpose of pump to transfer liquid helium from supply to receiver vessel, or to provide liquid helium flow for testing and experimentation.

  5. Liquid sampling system

    DOEpatents

    Larson, L.L.

    1984-09-17

    A conduit extends from a reservoir through a sampling station and back to the reservoir in a closed loop. A jet ejector in the conduit establishes suction for withdrawing liquid from the reservoir. The conduit has a self-healing septum therein upstream of the jet ejector for receiving one end of a double-ended cannula, the other end of which is received in a serum bottle for sample collection. Gas is introduced into the conduit at a gas bleed between the sample collection bottle and the reservoir. The jet ejector evacuates gas from the conduit and the bottle and aspirates a column of liquid from the reservoir at a high rate. When the withdrawn liquid reaches the jet ejector the rate of flow therethrough reduces substantially and the gas bleed increases the pressure in the conduit for driving liquid into the sample bottle, the gas bleed forming a column of gas behind the withdrawn liquid column and interrupting the withdrawal of liquid from the reservoir. In the case of hazardous and toxic liquids, the sample bottle and the jet ejector may be isolated from the reservoir and may be further isolated from a control station containing remote manipulation means for the sample bottle and control valves for the jet ejector and gas bleed. 5 figs.

  6. Liquid sampling system

    DOEpatents

    Larson, Loren L. (Idaho Falls, ID)

    1987-01-01

    A conduit extends from a reservoir through a sampling station and back to the reservoir in a closed loop. A jet ejector in the conduit establishes suction for withdrawing liquid from the reservoir. The conduit has a self-healing septum therein upstream of the jet ejector for receiving one end of a double-ended cannula, the other end of which is received in a serum bottle for sample collection. Gas is introduced into the conduit at a gas bleed between the sample collection bottle and the reservoir. The jet ejector evacuates gas from the conduit and the bottle and aspirates a column of liquid from the reservoir at a high rate. When the withdrawn liquid reaches the jet ejector the rate of flow therethrough reduces substantially and the gas bleed increases the pressure in the conduit for driving liquid into the sample bottle, the gas bleed forming a column of gas behind the withdrawn liquid column and interrupting the withdrawal of liquid from the reservoir. In the case of hazardous and toxic liquids, the sample bottle and the jet ejector may be isolated from the reservoir and may be further isolated from a control station containing remote manipulation means for the sample bottle and control valves for the jet ejector and gas bleed.

  7. Liquid metal drop ejection

    NASA Technical Reports Server (NTRS)

    Khuri-Yakub, B. T.

    1993-01-01

    The aim of this project was to demonstrate the possibility of ejecting liquid metals using drop on demand printing technology. The plan was to make transducers for operation in the 100 MHz frequency range and to use these transducers to demonstrate the ability to eject drops of liquid metals such as gallium. Two transducers were made by indium bonding piezoelectric lithium niobate to quartz buffer rods. The lithium niobate plates were thinned by mechanical polishing to a thickness of 37 microns for operation at 100 MHz. Hemispherical lenses were polished in the opposite ends of the buffer rods. The lenses, which focus the sound waves in the liquid metal, had an F-number equals 1. A mechanical housing was made to hold the transducers and to allow precise control over the liquid level above the lens. We started by demonstrating the ability to eject drops of water on demand. The drops of water had a diameter of 15 microns which corresponds to the wavelength of the sound wave in the water. A videotape of this ejection was made. We then used a mixture of Gallium and Indium (used to lower the melting temperature of the Gallium) to demonstrate the ejection of liquid metal drops. This proved to be difficult because of the oxide skin which forms on the surface of the liquid. In some instances, we were able to eject metal drops, however, this was not consistent and reproducible. An experiment was set up at NASA-Lewis to stabilize the process of drop on demand liquid metal ejection. The object was to place the transducer and liquid metal in a vacuum station so that no oxide would form on the surface. We were successful in demonstrating that liquid metals could be ejected on demand and that this technology could be used for making sheet metal in space.

  8. Liquid metals. Concepts and theory.

    NASA Astrophysics Data System (ADS)

    March, N. H.

    A research level comprehensive introduction to the theory and concepts of liquid metals. The book begins with a survey of the basic experimental facts and reviews the concepts needed to understand the properties of liquid metals. The quantitative theory of liquid pair correlation functions, effective ion-ion interactions, thermodynamic properties, and electronic and atomic transport is then developed. The book goes on to discuss inelastic neutron scattering from bulk liquid metals, a discussion of critical behavior, magnetism, and present understanding of the liquid metal surface, binary liquid metal alloys, the two component theory of pure liquid metals, shock wave studies, liquid hydrogen plasmas, and the constitution of giant planets.

  9. Liquid crystalline bispropargyl thermosets

    SciTech Connect

    Langlois, D.A.; Benicewicz, B.C.; Douglas, E.P.

    1998-11-01

    A series of rigid-rod bispropargyl thermoset monomers have been synthesized. These monomers were examined by differential scanning calorimetry (DSC) and hot stage polarized optical microscopy. Enantiotropic or monotropic nematic liquid crystalline phases were observed for all but two monomers. Partial curing of these reactive liquid crystalline monomers resulted in the formation of stable liquid crystalline phases with broad nematic phase after partial curing. DSC investigations indicated that the onset temperature of thermally induced cross-linking was approximately 260 C and insensitive to the phase type. The rate of cure was insensitive to the phase in which the cure occurred due to the unusual reaction mechanism for the propargyl end group.

  10. Liquid metal electric pump

    DOEpatents

    Abbin, J.P.; Andraka, C.E.; Lukens, L.L.; Moreno, J.B.

    1992-01-14

    An electrical pump for pumping liquid metals to high pressures in high temperature environments without the use of magnets or moving mechanical parts. The pump employs a non-porous solid electrolyte membrane, typically ceramic, specific to the liquid metal to be pumped. A DC voltage is applied across the thickness of the membrane causing ions to form and enter the membrane on the electrically positive surface, with the ions being neutralized on the opposite surface. This action provides pumping of the liquid metal from one side of the non-porous solid electrolyte membrane to the other. 3 figs.

  11. Liquid metal electric pump

    DOEpatents

    Abbin, Joseph P. (Albuquerque, NM); Andraka, Charles E. (Albuquerque, NM); Lukens, Laurance L. (Albuquerque, NM); Moreno, James B. (Albuquerque, NM)

    1992-01-01

    An electrical pump for pumping liquid metals to high pressures in high temperature environments without the use of magnets or moving mechanical parts. The pump employs a non-porous solid electrolyte membrane, typically ceramic, specific to the liquid metal to be pumped. A DC voltage is applied across the thickness of the membrane causing ions to form and enter the membrane on the electrically positive surface, with the ions being neutralized on the opposite surface. This action provides pumping of the liquid metal from one side of the non-porous solid electrolyte membrane to the other.

  12. Liquid thickness gauge

    NASA Technical Reports Server (NTRS)

    Weinstein, Leonard M. (inventor)

    1988-01-01

    A method and apparatus are developed to measure the thickness of a liquid on a surface independent of liquid conductivity. Two pairs of round, corrosion resistant wires are mounted in an insulating material such that the cross-sectional area of each wire is flush with and normal to the surface. The resistance between each pair of wires is measured using two ac resistance measuring circuits, in which the ratio of the outputs of the two resistance measuring circuits is indicative of the thickness of the liquid on the surface.

  13. Liquid rising near walls

    NASA Astrophysics Data System (ADS)

    Khorrami, Mohammad; Aghamohammadi, Amir

    2016-03-01

    The rise of a liquid in a region confined with walls is studied. This is done for the case of a liquid between two vertical parallel walls, as well as a liquid rising inside or outside a cylinder of circular cross section. Limiting cases of small distances between the walls, or tubes of small cross sections, as well as large distances between the walls, or tubes of large cross sections, are also investigated. For the limiting cases, tubes of arbitrary (but uniform) cross sections are also studied.

  14. Encapsulated liquid sorbents for carbon dioxide capture.

    PubMed

    Vericella, John J; Baker, Sarah E; Stolaroff, Joshuah K; Duoss, Eric B; Hardin, James O; Lewicki, James; Glogowski, Elizabeth; Floyd, William C; Valdez, Carlos A; Smith, William L; Satcher, Joe H; Bourcier, William L; Spadaccini, Christopher M; Lewis, Jennifer A; Aines, Roger D

    2015-01-01

    Drawbacks of current carbon dioxide capture methods include corrosivity, evaporative losses and fouling. Separating the capture solvent from infrastructure and effluent gases via microencapsulation provides possible solutions to these issues. Here we report carbon capture materials that may enable low-cost and energy-efficient capture of carbon dioxide from flue gas. Polymer microcapsules composed of liquid carbonate cores and highly permeable silicone shells are produced by microfluidic assembly. This motif couples the capacity and selectivity of liquid sorbents with high surface area to facilitate rapid and controlled carbon dioxide uptake and release over repeated cycles. While mass transport across the capsule shell is slightly lower relative to neat liquid sorbents, the surface area enhancement gained via encapsulation provides an order-of-magnitude increase in carbon dioxide absorption rates for a given sorbent mass. The microcapsules are stable under typical industrial operating conditions and may be used in supported packing and fluidized beds for large-scale carbon capture. PMID:25652243

  15. Encapsulated liquid sorbents for carbon dioxide capture

    NASA Astrophysics Data System (ADS)

    Vericella, John J.; Baker, Sarah E.; Stolaroff, Joshuah K.; Duoss, Eric B.; Hardin, James O.; Lewicki, James; Glogowski, Elizabeth; Floyd, William C.; Valdez, Carlos A.; Smith, William L.; Satcher, Joe H.; Bourcier, William L.; Spadaccini, Christopher M.; Lewis, Jennifer A.; Aines, Roger D.

    2015-02-01

    Drawbacks of current carbon dioxide capture methods include corrosivity, evaporative losses and fouling. Separating the capture solvent from infrastructure and effluent gases via microencapsulation provides possible solutions to these issues. Here we report carbon capture materials that may enable low-cost and energy-efficient capture of carbon dioxide from flue gas. Polymer microcapsules composed of liquid carbonate cores and highly permeable silicone shells are produced by microfluidic assembly. This motif couples the capacity and selectivity of liquid sorbents with high surface area to facilitate rapid and controlled carbon dioxide uptake and release over repeated cycles. While mass transport across the capsule shell is slightly lower relative to neat liquid sorbents, the surface area enhancement gained via encapsulation provides an order-of-magnitude increase in carbon dioxide absorption rates for a given sorbent mass. The microcapsules are stable under typical industrial operating conditions and may be used in supported packing and fluidized beds for large-scale carbon capture.

  16. Polyester Spherulite Crystallization in Ionic Liquids

    NASA Astrophysics Data System (ADS)

    Singfield, Kathy; Mitchell, Shawna

    2009-03-01

    A series of polyesters have been crystallized in ionic liquids. Spherulites of the polyesters have been grown isothermally from different ionic liquids after cooling the single phase polymer/ionic liquid system from above the polymer melting point temperature. To the authors' best knowledge this is the first reported account of polyester spherulites grown from these non-traditional solvents. The combination of physical properties of the crystallizing system supports the un-restrained branching/splitting volume-filling growth in all radial directions of the suspended crystallizing entity. The morphology of the collected spherulites at various stages of their formation was examined using scanning electron microscopy (SEM). The SEM results provide a clear visual inspection of the early-stage growth forms and the branching/splitting patterns involved in their evolution to the final spherical form.

  17. Maintenance evaluation for space station liquid systems

    NASA Technical Reports Server (NTRS)

    Flugel, Charles

    1987-01-01

    Many of the thermal and environmental control life support subsystems as well as other subsystems of the space station utilize various liquids and contain components which are either expendables or are life-limited in some way. Since the space station has a 20-year minimum orbital lifetime requirement, there will also be random failures occurring within the various liquid-containing subsystems. These factors as well as the planned space station build-up sequence require that maintenance concepts be developed prior to the design phase. This applies to the equipment which needs maintenance as well as the equipment which may be required at a maintenance work station within the space station. This paper presents several maintenance concepts for liquid-containing items and a flight experiment program which would allow for evaluation and improvement of these concepts so they can be incorporated in the space station designs at the outset of its design phase.

  18. Erasing no-mans land by thermodynamically stabilizing the liquid-liquid transition in tetrahedral particles

    PubMed Central

    Smallenburg, Frank; Filion, Laura; Sciortino, Francesco

    2014-01-01

    One of the most controversial hypotheses for explaining the origin of the thermodynamic anomalies characterizing liquid water postulates the presence of a metastable second-order liquid-liquid critical point [1] located in the no-mans land [2]. In this scenario, two liquids with distinct local structure emerge near the critical temperature. Unfortunately, since spontaneous crystallization is rapid in this region, experimental support for this hypothesis relies on significant extrapolations, either from the metastable liquid or from amorphous solid water [3, 4]. Although the liquid-liquid transition is expected to feature in many tetrahedrally coordinated liquids, including silicon [5], carbon [6] and silica, even numerical studies of atomic and molecular models have been unable to conclusively prove the existence of this transition. Here we provide such evidence for a model in which it is possible to continuously tune the softness of the interparticle interaction and the flexibility of the bonds, the key ingredients controlling the existence of the critical point. We show that conditions exist where the full coexistence is thermodynamically stable with respect to crystallization. Our work offers a basis for designing colloidal analogues of water exhibiting liquid-liquid transitions in equilibrium, opening the way for experimental confirmation of the original hypothesis. PMID:25264453

  19. Cyrogenic Life Support Technology Development Project

    NASA Technical Reports Server (NTRS)

    Bush, David R.

    2015-01-01

    KSC has used cryogenic life support (liquid air based) technology successfully for many years to support spaceflight operations. This technology has many benefits unique to cryogenics when compared to traditional compressed gas systems: passive cooling, lighter, longer duration, and lower operating pressure. However, there are also several limiting factors that have prevented the technology from being commercialized. The National Institute of Occupational Safety and Health, Office of Mine Safety and Health Research (NIOSH-OMSHR) has partnered with NASA to develop a complete liquid air based life support solution for emergency mine escape and rescue. The project will develop and demonstrate various prototype devices and incorporate new technological innovations that have to date prevented commercialization.

  20. Direct liquid injection of liquid petroleum gas

    SciTech Connect

    Lewis, D.J.; Phipps, J.R.

    1984-02-14

    A fuel injector and injection system for injecting liquified petroleum gas (LPG) into at least one air/fuel mixing chamber from a storage means that stores pressurized LPG in its liquid state. The fuel injector (including a body), adapted to receive pressurized LPG from the storage means and for selectively delivering the LPG to the air/fuel mixing chamber in its liquified state. The system including means for correcting the injector activation signal for pressure and density variations in the fuel.

  1. Extensible automated dispersive liquid-liquid microextraction.

    PubMed

    Li, Songqing; Hu, Lu; Chen, Ketao; Gao, Haixiang

    2015-05-01

    In this study, a convenient and extensible automated ionic liquid-based in situ dispersive liquid-liquid microextraction (automated IL-based in situ DLLME) was developed. 1-Octyl-3-methylimidazolium bis[(trifluoromethane)sulfonyl]imide ([C8MIM]NTf2) is formed through the reaction between [C8MIM]Cl and lithium bis[(trifluoromethane)sulfonyl]imide (LiNTf2) to extract the analytes. Using a fully automatic SPE workstation, special SPE columns packed with nonwoven polypropylene (NWPP) fiber, and a modified operation program, the procedures of the IL-based in situ DLLME, including the collection of a water sample, injection of an ion exchange solvent, phase separation of the emulsified solution, elution of the retained extraction phase, and collection of the eluent into vials, can be performed automatically. The developed approach, coupled with high-performance liquid chromatography-diode array detection (HPLC-DAD), was successfully applied to the detection and concentration determination of benzoylurea (BU) insecticides in water samples. Parameters affecting the extraction performance were investigated and optimized. Under the optimized conditions, the proposed method achieved extraction recoveries of 80% to 89% for water samples. The limits of detection (LODs) of the method were in the range of 0.16-0.45 ng mL(-1). The intra-column and inter-column relative standard deviations (RSDs) were <8.6%. Good linearity (r>0.9986) was obtained over the calibration range from 2 to 500 ng mL(-1). The proposed method opens a new avenue for automated DLLME that not only greatly expands the range of viable extractants, especially functional ILs but also enhances its application for various detection methods. Furthermore, multiple samples can be processed simultaneously, which accelerates the sample preparation and allows the examination of a large number of samples. PMID:25892068

  2. Exploration Life Support Technology Development Challenges

    NASA Technical Reports Server (NTRS)

    Chambliss Joe; Rulis, Susan

    2007-01-01

    The Exploration Life Support project is developing technologies to address the needs for life support during NASA s exploration missions. The focus of development is Air Revitalization, Water Recovery, and Waste Management Systems (ARS, WRS, and WMS). The approach to meeting exploration needs for life support intrinsically involves processing mixtures of gases, liquids and solids; thus the effects of micro or hypo gravity must be considered in developing and verifying the technologies. This paper provides an overview of the ELS project, how ELS technologies are planned to be used in exploration vehicles and the challenges being addressed.

  3. Ionic Liquid Membranes for Carbon Dioxide Separation

    SciTech Connect

    Myers, C.R.; Ilconich, J.B.; Luebke, D.R.; Pennline, H.W.

    2008-07-12

    Recent scientific studies are rapidly advancing novel technological improvements and engineering developments that demonstrate the ability to minimize, eliminate, or facilitate the removal of various contaminants and green house gas emissions in power generation. The Integrated Gasification Combined Cycle (IGCC) shows promise for carbon dioxide mitigation not only because of its higher efficiency as compared to conventional coal firing plants, but also due to a higher driving force in the form of high partial pressure. One of the novel technological concepts currently being developed and investigated is membranes for carbon dioxide (CO2) separation, due to simplicity and ease of scaling. A challenge in using membranes for CO2 capture in IGCC is the possibility of failure at elevated temperatures or pressures. Our earlier research studies examined the use of ionic liquids on various supports for CO2 separation over the temperature range, 37°C-300°C. The ionic liquid, 1-hexyl-3methylimidazolium Bis(trifluoromethylsulfonyl)imide, ([hmim][Tf2N]), was chosen for our initial studies with the following supports: polysulfone (PSF), poly(ether sulfone) (PES), and cross-linked nylon. The PSF and PES supports had similar performance at room temperature, but increasing temperature caused the supported membranes to fail. The ionic liquid with the PES support greatly affected the glass transition temperature, while with the PSF, the glass transition temperature was only slightly depressed. The cross-linked nylon support maintained performance without degradation over the temperature range 37-300°C with respect to its permeability and selectivity. However, while the cross-linked nylon support was able to withstand temperatures, the permeability continued to increase and the selectivity decreased with increasing temperature. Our studies indicated that further testing should examine the use of other ionic liquids, including those that form chemical complexes with CO2 based on amine interactions. The hypothesis is that the performance at the elevated temperatures could be improved by allowing a facilitated transport mechanism to become dominant. Several amine-based ionic liquids were tested on the cross-linked nylon support. It was found that using the amine-based ionic liquid did improve selectivity and permeability at higher temperature. The hypothesis was confirmed, and it was determined that the type of amine used also played a role in facilitated transport. Given the appropriate aminated ionic liquid with the cross-linked nylon support, it is possible to have a membrane capable of separating CO2 at IGCC conditions. With this being the case, the research has expanded to include separation of other constituents besides CO2 (CO, H2S, etc.) and if they play a role in membrane poisoning or degradation. This communication will discuss the operation of the recently fabricated ionic liquid membranes and the impact of gaseous components other than CO2 on their performance and stability.

  4. Liquid Oxygen/Liquid Methane Integrated Propulsion System Test Bed

    NASA Technical Reports Server (NTRS)

    Flynn, Howard; Lusby, Brian; Villemarette, Mark

    2011-01-01

    In support of NASA?s Propulsion and Cryogenic Advanced Development (PCAD) project, a liquid oxygen (LO2)/liquid methane (LCH4) Integrated Propulsion System Test Bed (IPSTB) was designed and advanced to the Critical Design Review (CDR) stage at the Johnson Space Center. The IPSTB?s primary objectives are to study LO2/LCH4 propulsion system steady state and transient performance, operational characteristics and to validate fluid and thermal models of a LO2/LCH4 propulsion system for use in future flight design work. Two phase thermal and dynamic fluid flow models of the IPSTB were built to predict the system performance characteristics under a variety of operating modes and to aid in the overall system design work. While at ambient temperature and simulated altitude conditions at the White Sands Test Facility, the IPSTB and its approximately 600 channels of system instrumentation would be operated to perform a variety of integrated main engine and reaction control engine hot fire tests. The pressure, temperature, and flow rate data collected during this testing would then be used to validate the analytical models of the IPSTB?s thermal and dynamic fluid flow performance. An overview of the IPSTB design and analytical model development will be presented.

  5. Liquid cooled garments

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Liquid cooled garments employed in several applications in which severe heat is encountered are discussed. In particular, the use of the garments to replace air line cooling units in a variety of industrial processing situations is discussed.

  6. Ionic liquid ethanol sensor.

    PubMed

    Lee, Yuan Gee; Chou, Tse-Chuan

    2004-07-30

    Ionic liquids containing lithium methylsulfonyl group were prepared from the precursors poly(propylene glycol)-block-(ethylene glycol)-block-(propylene glycol)-bis(2-aminopropyl ether) with different molecular weight. These liquids revealed excellent electrical conductivity in the temperature range -25 to 85 degrees C. Also, they exhibited a high boiling temperature and hence a low vapor pressure in ambient condition. Additionally, they showed a high fluidity with their viscosities being comparative with that of water. To determine the sensitivity of an ethanol sensor by using these ionic liquids, these liquids were subjected into a sequential electrochemical tests with nickel electrodes which performed a high sensitivity for the ethanol sensor. It was found that only the derivative with low molecular weight could detect ethanol. Furthermore, a linear relationship between the response current and the concentration of ethanol was constructed. The detection limit was found to be 0.13% (v/v) and its response time was 336 s. PMID:15142574

  7. Liquid medication administration

    MedlinePLUS

    ... cooking are accurate, but they spill easily. Oral syringes have some advantages for giving liquid medications. They ... easy to use. You can take a capped syringe containing a dose of medication to your child's ...

  8. Wettability by Ionic Liquids.

    PubMed

    Liu, Hongliang; Jiang, Lei

    2016-01-01

    Ionic liquids (ILs) have become particularly attractive recently because they have demonstrated themselves to be important construction units in the broad fields of chemistry and materials science, from catalysis and synthesis to analysis and electrochemistry, from functional fluids to clean energy, from nanotechnology to functional materials. One of the greatest issues that determines the performance of ILs is the wettability of correlated surfaces. In this concept article, the key developments and issues in IL wettability are surveyed, including the electrowetting of ILs in gas-liquid-solid systems and liquid-liquid-solid systems, ILs as useful probe fluids, the superwettability of Ils, and future directions in IL wettability. This should generate extensive interest in the field and encourage more scientists to engage in this area to tackle its scientific challenges. PMID:26619157

  9. Safer Liquid Natural Gas

    NASA Technical Reports Server (NTRS)

    1976-01-01

    After the disaster of Staten Island in 1973 where 40 people were killed repairing a liquid natural gas storage tank, the New York Fire Commissioner requested NASA's help in drawing up a comprehensive plan to cover the design, construction, and operation of liquid natural gas facilities. Two programs are underway. The first transfers comprehensive risk management techniques and procedures which take the form of an instruction document that includes determining liquid-gas risks through engineering analysis and tests, controlling these risks by setting up redundant fail safe techniques, and establishing criteria calling for decisions that eliminate or accept certain risks. The second program prepares a liquid gas safety manual (the first of its kind).

  10. Lacerations - liquid bandage

    MedlinePLUS

    ... painless to apply. Skin adhesives, or liquid bandages, seal the cut closed after only one application. There ... scrub the site. Doing so may loosen the seal or even remove the adhesive completely. The seal ...

  11. Liquid-Cooled Garment

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A liquid-cooled bra, offshoot of Apollo moon suit technology, aids the cancer-detection technique known as infrared thermography. Water flowing through tubes in the bra cools the skin surface to improve resolution of thermograph image.

  12. Diet - full liquid

    MedlinePLUS

    ... 7 of the foods you can eat for breakfast, lunch, and dinner. Liquid foods DO NOT include " ... Nonfat dry milk added to your drinks Instant breakfast powder added to milk, puddings, custards, and milkshakes ...

  13. Liquid level controller

    DOEpatents

    Mangus, J.D.; Redding, A.H.

    1975-07-15

    A system for maintaining two distinct sodium levels within the shell of a heat exchanger having a plurality of J-shaped modular tube bundles each enclosed in a separate shell which extends from a common base portion. A lower liquid level is maintained in the base portion and an upper liquid level is maintained in the shell enwrapping the long stem of the J-shaped tube bundles by utilizing standpipes with a notch at the lower end which decreases in open area the distance from the end of the stand pipe increases and a supply of inert gas fed at a constant rate to produce liquid levels, which will remain generally constant as the flow of liquid through the vessel varies. (auth)

  14. The Liquid Nitrogen Fountain

    NASA Astrophysics Data System (ADS)

    McRae, Robin; Rahn, Jeffrey A.; Beamer, Timothy W.; Lebret, Norm

    2002-10-01

    Details of a demonstration using liquid nitrogen are presented. The demonstration is based on a 500-mL transparent polyethylene soft-drink bottle with a screw-on pop-up drink top. Prior to the demonstration, a balloon is placed over the popped-up spout of the bottle top. The bottle is filled with liquid nitrogen and the top, with the balloon affixed, is quickly put in place and screwed on tightly. As the liquid nitrogen in the bottle boils, the balloon inflates. When the balloon bursts the noise produced is far greater than would ordinarily be expected, and a fountain of liquid nitrogen and condensing water vapor shoots into the air above the bottle.

  15. Liquid sample processor

    NASA Technical Reports Server (NTRS)

    Jahnsen, V. J.; Campen, C. F., Jr.

    1975-01-01

    Processor is automatic and includes series of extraction tubes packed with fibrous absorbent material of large surface area. When introduced into these tubes, liquid test samples become completely absorbed by packing material as thin film.

  16. Liquid metal boiling inception

    NASA Technical Reports Server (NTRS)

    Sabin, C. M.; Poppendiek, H. F.; Mouritzen, G.; Meckel, P. T.; Cloakey, J. E.

    1972-01-01

    An experimental study of the inception of boiling in potassium in forced convection is reported. The boiler consisted of a 0.19-inch inside diameter, niobium-1% zirconium boiler tube approximately six feet long. Heating was accomplished by direct electrical tube wall conduction. Experiments were performed with both all-liquid fill and two-phase fill startup sequences and with a range of flow rates, saturation temperatures, inert gas levels, and fill liquid temperatures. Superheat of the liquid above the equilibrium saturation temperature was observed in all the experiments. Incipient boiling liquid superheat ranged from a few degrees to several hundred. Comparisons of these data with other data and with several analytical treatments are presented.

  17. 114. WEST SIDE OF LIQUID OXYGEN CONTROL ROOM (205). LIQUID ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    114. WEST SIDE OF LIQUID OXYGEN CONTROL ROOM (205). LIQUID NITROGEN (LN2) SUBCOOLER ON LEFT; SKID 8, LIQUID OXYGEN CONTROLLER FOR SWITCHING BETWEEN RAPID-LOAD AND TOPPING ON RIGHT. LIQUID OXYGEN LINE FROM SKID 9A AT RIGHT EDGE OF PHOTO. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  18. Liquid Level Sensing System

    NASA Technical Reports Server (NTRS)

    Korman, Valentin (Inventor); Wiley, John T. (Inventor); Duffell, Amanda G. (Inventor)

    2014-01-01

    A liquid level sensing system includes waveguides disposed in a liquid and distributed along a path with a gap between adjacent waveguides. A source introduces electromagnetic energy into the waveguides at a first end of the path. A portion of the electromagnetic energy exits the waveguides at a second end of the path. A detector measures the portion of the electromagnetic energy exiting the second end of the path.

  19. Liquid blocking check valve

    SciTech Connect

    Merrill, John T.

    1984-01-01

    A liquid blocking check valve useful particularly in a pneumatic system utilizing a pressurized liquid fill chamber. The valve includes a floatable ball disposed within a housing defining a chamber. The housing is provided with an inlet aperture disposed in the top of said chamber, and an outlet aperture disposed in the bottom of said chamber in an offset relation to said inlet aperture and in communication with a cutaway side wall section of said housing.

  20. Advanced proteomic liquid chromatography

    PubMed Central

    Xie, Fang; Smith, Richard D.; Shen, Yufeng

    2012-01-01

    Liquid chromatography coupled with mass spectrometry is the predominant platform used to analyze proteomics samples consisting of large numbers of proteins and their proteolytic products (e.g., truncated polypeptides) and spanning a wide range of relative concentrations. This review provides an overview of advanced capillary liquid chromatography techniques and methodologies that greatly improve separation resolving power and proteomics analysis coverage, sensitivity, and throughput. PMID:22840822

  1. Applications of ionic liquids.

    PubMed

    Patel, Divia Dinesh; Lee, Jong-Min

    2012-06-01

    Ionic liquids have recently gained popularity in the scientific community owing to their special properties and characteristics. One of the reasons why ionic liquids have been termed "green solvents" is due to their negligible vapour pressure. Their use in electrochemical, biological and metal extraction applications is discussed. Wide research has been carried out for their use in batteries, solar panels, fuel cells, drug deliveries and biomass pretreatments. This work aims to consolidate the various findings from previous works in these areas. PMID:22711528

  2. Photorheological ionic liquids.

    PubMed

    Av, Joo; Cidade, M T; Rodriguez, Vincent; Lima, Joo C; Parola, A Jorge

    2015-06-01

    Two room temperature ionic liquids (ILs) bearing coumarin and p-hydroxycinnamic acid moieties are synthesized, and their photochemistry is studied in solution and neat conditions. Irradiation at absorption maxima leads to photochemical transformations and results in changes of their rheological properties which are evaluated by rotational rheometry. Samples of ionic liquids are also studied by Hyper-Rayleigh scattering, and the effect of their photochemistry on ionic nanoaggregation is discussed. PMID:25970078

  3. Compact Liquid Deaerator

    NASA Technical Reports Server (NTRS)

    Yamauchi, S. T.

    1982-01-01

    Gases are removed from liquids by a new deaerator that takes up only 5 inches (12.7 cm) at top of a medium-sized storage tank. Deaerator has a multiple cascading header that exposes more fluid at lower pressures than typical commercial deaerators. Potential applications are in hydraulic systems for aircraft and heavy machinery, in cooling systems where deaerated liquid is needed to prevent cavitation of pump.

  4. Atmospheric Pressure Plasmas Incident onto Thin Liquid Layers

    NASA Astrophysics Data System (ADS)

    Tian, Wei; Norberg, Seth; Babaeva, Natalia Yu.; Kushner, Mark J.

    2013-09-01

    The interaction of plasmas with liquids has increasing importance in advanced manufacturing and biomedical applications. Sustaining atmospheric pressure plasmas on liquids (as opposed to in liquids) can increase the chemical activity of the liquid by transferring more easily produced reactive species from the gas phase into the liquid. Often the intent is to treat the surface under the liquid layer, as in plasma medicine. The liquid then acts as a filter which modifies the fluxes of reactive species prior to reaching the underlying surface. The liquid in turn influences the plasma by evaporation which produces a saturated layer of, for example, water vapor above the liquid surface, or by the shape of liquid covered wounds and the dielectric properties of the liquid. Direct plasma exposure (e.g., a dielectric barrier discharge) enables intersection of ion and UV/VUV fluxes with the liquid surface whereas many remote plasma jets typically do not. This increases the rate of hydronium (H3O+) production which affects pH. In this paper, results from a computational investigation on the dynamics of atmospheric pressure plasmas intersecting thin water layers having dissolved gases and proteins will be discussed. Examples are taken from DBD and plasma jet exposure of water layers over a tissue-like dielectric, and plasmas sustained in bubbles in water. The mutual interaction of the plasma and liquid will be discussed based on radiation and ion transport into the water, evaporation, and transport and conversion of plasma produced reactivity through the water layer. Work supported by DOE Fusion Energy Science and NSF.

  5. Thermal boundary conductance of hydrophilic and hydrophobic ionic liquids

    NASA Astrophysics Data System (ADS)

    Oyake, Takafumi; Sakata, Masanori; Yada, Susumu; Shiomi, Junichiro

    2015-03-01

    A solid/liquid interface plays a critical role for understanding mechanisms of biological and physical science. Moreover, carrier density of the surface is dramatically enhanced by electric double layer with ionic liquid, salt in the liquid state. Here, we have measured the thermal boundary conductance (TBC) across an interface of gold thin film and ionic liquid by using time-domain thermoreflectance technique. Following the prior researches, we have identified the TBC of two interfaces. One is gold and hydrophilic ionic liquid, N,N-Diethyl-N-methyl-N-(2-methoxyethyl) ammonium tetrafluoroborate (DEME-BF4), which is a hydrophilic ionic liquid, and the other is N,N-Diethyl-N-methyl-N-(2-methoxyethyl) ammonium bis (trifluoromethanesulfonyl) imide (DEME-TFSI), which is a hydrophobic ionic liquid. We found that the TBC between gold and DEME-TFIS (19 MWm-2K-1) is surprisingly lower than the interface between gold and DEME-BF4 (45 MWm-2K-1). With these data, the importance of the wetting angle and ion concentration for the thermal transport at the solid/ionic liquid interface is discussed. Part of this work is financially supported by Japan Society for the Promotion of Science (JSPS) and Japan Science and Technology Agency. The author is financially supported by JSPS Fellowship.

  6. Electrically actuated liquid iris.

    PubMed

    Xu, Miao; Ren, Hongwen; Lin, Yi-Hsin

    2015-03-01

    We report an adaptive iris using dielectric liquids and a radial-interdigitated electrode. A black liquid is confined by a circular gasket with a donut shape. The surrounding of the black liquid is filled with an immiscible liquid. In the relaxing state, the black liquid obtains the largest clear aperture. By applying a voltage, the surface of the black liquid is stretched by the generated dielectric force, resulting in a reduction of its aperture. For the demonstrated iris, the diameter of the aperture can be changed from ∼4.7  mm to ∼1.2  mm when the voltage is applied from 0 to 70  V(rms). The aperture ratio is ∼94%. Owing to the radial-interdigitated electrode, the aperture size of the iris can be effectively switched with a reasonably fast response time. The optical switch is polarization-insensitive. The potential applications of our iris are light shutters, optical attenuators, biomimicry, and wearable devices. PMID:25723444

  7. Data liquidity in health information systems.

    PubMed

    Courtney, Paul K

    2011-01-01

    In 2001, the Institute of Medicine report Crossing the Quality Chasm and the National Committee on Vital and Health Statistics report Information for Health were released, and they provided the context for the development of information systems used to support health-supporting processes. Both had as their goals, implicit or explicit, to ensure the right data are provided to the right person at the right time, which is one definition of "data liquidity." This concept has had some traction in recent years as a shorthand way to express a system property for health information technology, but there is not a well-defined characterization of what properties of a system or of its components give it better or worse data liquidity. This article looks at some recent work that help to identify those properties and perhaps can help to ground the concept with metrics that are assessable. PMID:21799328

  8. Liquid crystalline composites containing phyllosilicates

    DOEpatents

    Chaiko, David J.

    2004-07-13

    The present invention provides phyllosilicate-polymer compositions which are useful as liquid crystalline composites. Phyllosilicate-polymer liquid crystalline compositions of the present invention can contain a high percentage of phyllosilicate while at the same time be transparent. Because of the ordering of the particles liquid crystalline composite, liquid crystalline composites are particularly useful as barriers to gas transport.

  9. Active colloids at liquid-liquid interfaces: dynamic self-assembly and functionality

    NASA Astrophysics Data System (ADS)

    Snezhko, Alexey; Aranson, Igor

    2012-02-01

    Self-assembled materials must actively consume energy and remain out of equilibrium in order to support structural complexity and functional diversity. Colloids of interacting particles suspended at liquid-liquid interfaces and maintained out of equilibrium by external alternating electromagnetic fields develop nontrivial collective dynamics and self-assembly. We use ferromagnetic colloidal micro-particles (so the magnetic moment is fixed in each particle and interactions between colloids is highly anisotropic and directional) suspended over an interface of two immiscible liquids and energized by vertical alternating magnetic fields to demonstrate novel dynamic and active self-assembled structures (``asters'') which are not accessible through thermodynamic assembly. Structures are attributed to the interplay between surface waves, generated at the liquid/liquid interface by the collective response of magnetic microparticles to the alternating magnetic field, and hydrodynamic fields induced in the boundary layers of both liquids forming the interface. Two types of magnetic order are reported. We demonstrate that asters develop self-propulsion in the presence of a small in-plane dc magnetic field. We show that asters can capture, transport, and position target microparticles.

  10. Impact of Liquid Fuel Boundary Condition and Nozzle Geometry on Liquid Jet in Crossflow Atomization

    NASA Astrophysics Data System (ADS)

    Ghods, Sina; Herrmann, Marcus

    2012-11-01

    The atomization of a liquid jet by a high speed cross-flowing gas has many applications such as gas turbines and augmentors. The mechanisms by which the liquid jet initially breaks up, however, are not well understood. Experimental studies suggest the dependence of spray properties on operating conditions and nozzle geometry. Detailed numerical simulations can offer better understanding of the underlying physical mechanisms that lead to the breakup of the injected liquid jet. In this work, we present detailed numerical simulation results of turbulent liquid jets injected into turbulent gaseous cross flows for different liquid fuel boundary conditions and injector geometries. We employ a finite volume, balanced force fractional step flow solver to solve the Navier-Stokes equations coupled to a Refined Level Set Grid method to follow the phase interface. To enable the simulation of atomization of high density ratio fluids, we ensure discrete consistency between the solution of the conservative momentum equation and the level set based continuity equation by employing the Rescaled Conservative Momentum method. We analyze the impact of liquid jet turbulent fluctuations and injector geometry on different jet properties such as jet penetration and generated drop sizes. This work was supported by NSF grant number CBET-0853627.

  11. Calamitic liquid crystal elastomers swollen with bent-core liquid crystals

    NASA Astrophysics Data System (ADS)

    Chambers, M.; Gleeson, J. T.; Sprunt, S.; Jakli, A.

    2008-03-01

    Liquid crystal elastomers are composed of a chemically bonded liquid crystal mesogen and an elastomeric polymer network. They exhibit both the properties of rubber elasticity, liquid crystallinity and their interplay, giving rise to unique systems rich in physics. Additionally, bent-core (``banana'') liquid crystals are also of interest exhibiting rich phase behaviour and non-classical properties such as flexoelectricity. Here we examine the swelling of existing calamitic liquid crystal elastomers with various bent-core mesogens and the intriguing properties of the resulting system. The consequential swollen liquid crystalline elastomer systems, can imbibe many times there weight and volume in bent core mesogens until saturated. The homogenous system displays new properties (transition temperatures and phases) depending strongly on the interaction of the elastomer mesogen and bent-core mesogen. Strangely, for some bent-core mesogens this leads to higher temperature phase behaviour than both compounds originally posses. The authors would like to acknowledge support from ONR (N00014-07-1-0440) and NSF (DMR-0606160).

  12. Enhanced catalyst for converting synthesis gas to liquid motor fuels

    DOEpatents

    Coughlin, Peter K. (Yorktown Heights, NY)

    1986-01-01

    The conversion of synthesis gas to liquid molar fuels by means of a cobalt Fischer-Tropsch catalyst composition is enhanced by the addition of molybdenum, tungsten or a combination thereof as an additional component of said composition. The presence of the additive component increases the olefinic content of the hydrocarbon products produced. The catalyst composition can advantageously include a support component, such as a molecular sieve, co-catalyst/support component or a combination of such support components.

  13. Catalyst for converting synthesis gas to liquid motor fuels

    DOEpatents

    Coughlin, Peter K.

    1986-01-01

    The addition of an inert metal component, such as gold, silver or copper, to a Fischer-Tropsch catalyst comprising cobalt enables said catalyst to convert synthesis gas to liquid motor fuels at about 240.degree.-370.degree. C. with advantageously reduced selectivity of said cobalt for methane in said conversion. The catalyst composition can advantageously include a support component, such as a molecular sieve, co-catalyst/support component or a combination of such support components.

  14. Distinct Metallization and Atomization Transitions in Dense Liquid Hydrogen

    NASA Astrophysics Data System (ADS)

    Mazzola, Guglielmo; Sorella, Sandro

    2015-03-01

    We perform molecular dynamics simulations driven by accurate quantum Monte Carlo forces on dense liquid hydrogen. There is a recent report of a complete atomization transition between a mixed molecular-atomic liquid and a completely dissociated fluid in an almost unaccessible pressure range [Nat. Commun. 5, 3487 (2014)]. Here, instead, we identify a different transition between the fully molecular liquid and the mixed-atomic fluid at 400 GPa , i.e., in a much more interesting pressure range. We provide numerical evidence supporting the metallic behavior of this intermediate phase. Therefore, we predict that the metallization at finite temperature occurs in this partially dissociated molecular fluid, well before the complete atomization of the liquid. At high temperature this first-order transition becomes a crossover, in very good agreement with the experimental observation. Several systematic tests supporting the quality of our large scale calculations are also reported.

  15. Distinct metallization and atomization transitions in dense liquid hydrogen.

    PubMed

    Mazzola, Guglielmo; Sorella, Sandro

    2015-03-13

    We perform molecular dynamics simulations driven by accurate quantum Monte Carlo forces on dense liquid hydrogen. There is a recent report of a complete atomization transition between a mixed molecular-atomic liquid and a completely dissociated fluid in an almost unaccessible pressure range [Nat. Commun. 5, 3487 (2014)]. Here, instead, we identify a different transition between the fully molecular liquid and the mixed-atomic fluid at ?400??GPa, i.e., in a much more interesting pressure range. We provide numerical evidence supporting the metallic behavior of this intermediate phase. Therefore, we predict that the metallization at finite temperature occurs in this partially dissociated molecular fluid, well before the complete atomization of the liquid. At high temperature this first-order transition becomes a crossover, in very good agreement with the experimental observation. Several systematic tests supporting the quality of our large scale calculations are also reported. PMID:25815949

  16. A liquid propulsion panorama

    NASA Astrophysics Data System (ADS)

    Caisso, Philippe; Souchier, Alain; Rothmund, Christophe; Alliot, Patrick; Bonhomme, Christophe; Zinner, Walter; Parsley, Randy; Neill, Todd; Forde, Scott; Starke, Robert; Wang, William; Takahashi, Mamoru; Atsumi, Masahiro; Valentian, Dominique

    2009-12-01

    Liquid-propellant rocket engines are widely used all over the world, thanks to their high performances, in particular high thrust-to-weight ratio. The present paper presents a general panorama of liquid propulsion as a contribution of the IAF Advanced Propulsion Prospective Group. After a brief history of its past development in the different parts of the world, the current status of liquid propulsion, the currently observed trends, the possible areas of future improvement and a summarized road map of future developments are presented. The road map includes a summary of the liquid propulsion status presented in the "Year in review 2007" of Aerospace America. Although liquid propulsion is often seen as a mature technology with few areas of potential improvement, the requirements of an active commercial market and a renewed interest for space exploration has led to the development of a family of new engines, with more design margins, simpler to use and to produce associated with a wide variety of thrust and life requirements.

  17. Communication: Protein dynamical transition vs. liquid-liquid phase transition in protein hydration water

    NASA Astrophysics Data System (ADS)

    Schir, Giorgio; Fomina, Margarita; Cupane, Antonio

    2013-09-01

    In this work, we compare experimental data on myoglobin hydrated powders from elastic neutron scattering, broadband dielectric spectroscopy, and differential scanning calorimetry. Our aim is to obtain new insights on the connection between the protein dynamical transition, a fundamental phenomenon observed in proteins whose physical origin is highly debated, and the liquid-liquid phase transition (LLPT) possibly occurring in protein hydration water and related to the existence of a low temperature critical point in supercooled water. Our results provide a consistent thermodynamic/dynamic description which gives experimental support to the LLPT hypothesis and further reveals how fundamental properties of water and proteins are tightly related.

  18. Redox chemistry at liquid/liquid interfaces

    NASA Technical Reports Server (NTRS)

    Volkov, A. G.; Deamer, D. W.

    1997-01-01

    The interface between two immiscible liquids with immobilized photosynthetic pigments can serve as the simplest model of a biological membrane convenient for the investigation of photoprocesses accompanied by spatial separation of charges. As it follows from thermodynamics, if the resolvation energies of substrates and products are very different, the interface between two immiscible liquids may act as a catalyst. Theoretical aspects of charge transfer reactions at oil/water interfaces are discussed. Conditions under which the free energy of activation of the interfacial reaction of electron transfer decreases are established. The activation energy of electron transfer depends on the charges of the reactants and dielectric permittivity of the non-aqueous phase. This can be useful when choosing a pair of immiscible solvents to decrease the activation energy of the reaction in question or to inhibit an undesired process. Experimental interfacial catalytic systems are discussed. Amphiphilic molecules such as chlorophyll or porphyrins were studied as catalysts of electron transfer reactions at the oil/water interface.

  19. Liquid Effluent Monitoring Information System (LEMIS) System Construction

    SciTech Connect

    Adams, R.T.

    1994-10-11

    The liquid effluent sampling program is part of the effort to minimize adverse environmental impact during the cleanup operation at the Hanford Site. Of the 33 Phase I and Phase II liquid effluents, all streams actively discharged to the soil column will be sampled. The Liquid Effluent Monitoring Information System (LEMIS) is being developed as the organized information repository facility in support of the liquid effluent monitoring requirements of the Tri-Party Agreement. It is necessary to provide an automated repository into which the results from liquid effluent sampling will be placed. This repository must provide for effective retention, review, and retrieval of selected sample data by authorized persons and organizations. This System Construction document is the aggregation of the DMR P+ methodology project management deliverables. Together they represent a description of the project and its plan through four Releases, corresponding to the definition and prioritization of requirements defined by the user.

  20. Compatibility of structural materials with liquid bismuth, lead, and mercury

    SciTech Connect

    Weeks, J.R.

    1996-06-01

    During the 1950s and 1960s, a substantial program existed at Brookhaven National Laboratory as part of the Liquid Metal Fuel reactor program on the compatibility of bismuth, lead, and their alloys with structural materials. Subsequently, compatibility investigations of mercury with structural materials were performed in support of development of Rankine cycle mercury turbines for nuclear applications. The present talk will review present understanding of the corrosion/mass-transfer reactions of structural materials with these liquid metal coolants. Topics to be discussed include the basic solubility relationships of iron, chromium, nickel, and refractory metals in these liquid metals, the results of inhibition studies, the role of oxygen on the corrosion processes, and specialized topics such as cavitation-corrosion and liquid metal embrittlement. Emphasis will be placed on utilizing the understanding gained in this earlier work on the development of heavy liquid metal targets in spallation neutron sources.

  1. Free vibration analysis of a tank containing two liquids

    SciTech Connect

    Tang, Yu; Chang, Y.W.

    1993-05-01

    A study of the dynamic characteristics of rigidly supported upright circular cylindrical tanks containing two different liquids is presented. The governing differential equations for the tank-two liquid system are obtained by application of the Rayleigh-Ritz procedure in combination with Lagrange`s equation. The response functions examined include the fundamental natural frequency, the associated mode of vibration and hydrodynamic pressure exerted against the tank wall. Unlike the cases of tanks containing one liquid in which the dynamic response is controlled by four parameters, the dynamic response of a tank that contains two liquids is controlled by six parameters. The numerical results are presented in tabular and graphic forms, and are compared with those of the identical tank filled with one liquid. Also, a simple approximate equation for evaluating the fundamental natural frequency for preliminary design is proposed.

  2. The liquid-liquid phase transition in silicon revealed by snapshots of valence electrons.

    PubMed

    Beye, Martin; Sorgenfrei, Florian; Schlotter, William F; Wurth, Wilfried; Fhlisch, Alexander

    2010-09-28

    The basis for the anomalies of water is still mysterious. Quite generally tetrahedrally coordinated systems, also silicon, show similar thermodynamic behavior but lack--like water--a thorough explanation. Proposed models--controversially discussed--explain the anomalies as a remainder of a first-order phase transition between high and low density liquid phases, buried deeply in the "no man's land"--a part of the supercooled liquid region where rapid crystallization prohibits any experimental access. Other explanations doubt the existence of the phase transition and its first-order nature. Here, we provide experimental evidence for the first-order-phase transition in silicon. With ultrashort optical pulses of femtosecond duration we instantaneously heat the electronic system of silicon while the atomic structure as defined by the much heavier nuclear system remains initially unchanged. Only on a picosecond time scale the energy is transferred into the atomic lattice providing the energy to drive the phase transitions. With femtosecond X-ray pulses from FLASH, the free-electron laser at Hamburg, we follow the evolution of the valence electronic structure during this process. As the relevant phases are easily distinguishable in their electronic structure, we track how silicon melts into the low-density-liquid phase while a second phase transition into the high-density-liquid phase only occurs after the latent heat for the first-order phase transition has been transferred to the atomic structure. Proving the existence of the liquid-liquid phase transition in silicon, the hypothesized liquid-liquid scenario for water is strongly supported. PMID:20805512

  3. Modeling of Diffusion in Liquid Ge and Its Alloys

    NASA Technical Reports Server (NTRS)

    Stroud, David G.

    1998-01-01

    This report summarizes progress made on NASA Grant NAG3-1437, Modeling of diffusion in Liquid Ge and Its Alloys, which was in effect from January 15, 1993 through July 10, 1997. It briefly describes the purpose of the grant, and the work accomplished in simulations and other studies of thermophysical properties of liquid semiconductors and related materials. A list of publications completed with the support of the grant is also given.

  4. Containerless Liquid-Phase Processing of Ceramic Materials

    NASA Technical Reports Server (NTRS)

    Weber, J. K. Richard (Principal Investigator); Nordine, Paul C.

    1996-01-01

    The present project builds on the results of research supported under a previous NASA grant to investigate containerless liquid-phase processing of molten ceramic materials. The research used an aero-acoustic levitator in combination with cw CO2 laser beam heating to achieve containerless melting, superheating, undercooling, and solidification of poorly-conducting solids and liquids. Experiments were performed on aluminum oxide, binary aluminum oxide-silicon dioxide materials, and oxide superconductors.

  5. Evaluation of mercury in the liquid waste processing facilities

    SciTech Connect

    Jain, Vijay; Shah, Hasmukh; Occhipinti, John E.; Wilmarth, William R.; Edwards, Richard E.

    2015-08-13

    This report provides a summary of Phase I activities conducted to support an Integrated Evaluation of Mercury in Liquid Waste System (LWS) Processing Facilities. Phase I activities included a review and assessment of the liquid waste inventory and chemical processing behavior of mercury using a system by system review methodology approach. Gaps in understanding mercury behavior as well as action items from the structured reviews are being tracked. 64% of the gaps and actions have been resolved.

  6. Magnetogravitational potential revealed near a liquid-vapor critical point

    NASA Astrophysics Data System (ADS)

    Lorin, Clment; Mailfert, Alain; Chatain, Denis; Flice, Hlne; Beysens, D.

    2009-08-01

    Magnetic forces are increasingly used to compensate weight in multiphase matter (solids, liquids, or vapor), but compensation cannot be strictly uniform. In order to determine quantitatively the remaining forces, a magnetogravitational potential was constructed. The potential can be revealed by the shape of the liquid-vapor interfaces near the critical point, where the interfacial tension vanishes. Experiments near the critical point of H2 (33K) are reported which support this finding.

  7. Controllable liquid crystal dampers

    NASA Astrophysics Data System (ADS)

    Tani, Junji; Ohtomo, Kikuo

    1998-04-01

    This paper describes an experimental study on the vibration suppression of rotary shaft using liquid crystal. A controllable rotary damper using liquid crystal with nematic phase is proposed and applied to the vibration suppression of a rotary shaft and a pendulum. Two disks were mounted inside a housing, which were attached to rotary shafts. These disks are free to rotate inside and relative to the housing. Damping is introduced by filling the space between housing and disk with liquid crystal, apparent viscosity of which can be controlled by the applied electric field. The results show that the torsional vibration of the rotary shaft, and the free vibration and parametric resonance of the pendulum are suppressed effectively.

  8. Buckling of Liquid Columns

    NASA Astrophysics Data System (ADS)

    Habibi, M.; Rahmani, Y.; Bonn, Daniel; Ribe, N. M.

    2010-02-01

    Under appropriate conditions, a column of viscous liquid falling onto a rigid surface undergoes a buckling instability. Here we show experimentally and theoretically that liquid buckling exhibits a hitherto unsuspected complexity involving three different modesviscous, gravitational, and inertialdepending on how the viscous forces that resist bending of the column are balanced. We also find that the nonlinear evolution of the buckling exhibits a surprising multistability with three distinct states: steady stagnation flow, liquid rope coiling, and a new state in which the column simultaneously folds periodically and rotates about a vertical axis. The transitions among these states are subcritical, leading to a complex phase diagram in which different combinations of states coexist in different regions of the parameter space.

  9. Liquid lubrication in space

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.

    1990-01-01

    The requirement for long-term, reliable operation of aerospace mechanisms has, with a few exceptions, pushed the state of the art in tribology. Space mission life requirements in the early 1960s were generally 6 months to a year. The proposed U.S. space station schedule to be launched in the 1990s must be continuously usable for 10 to 20 years. Liquid lubrication systems are generally used for mission life requirements longer than a year. Although most spacecraft or satellites have reached their required lifetimes without a lubrication-related failure, the application of liquid lubricants in the space environment presents unique challenges. The state of the art of liquid lubrication in space as well as the problems and their solutions are reviewed.

  10. Treating gases with liquids

    SciTech Connect

    Aubert, R.P.

    1984-09-11

    Gas, such as exhaust gas from a silicon epitaxial reactor, is treated with a liquid such as water. A basin holds a solution including the liquid utilized to treat such gas in the manner intended. An inlet chamber and a convenient self-cleaning passageway introduce the gas into and below a first level of solution established within a treatment chamber in the basin. Within delivery piping, pressure is provided for advancing the gas for treatment. The treatment chamber is provided with sidewalls having passageways, which cooperate with the gas pressure to establish multiple levels of solution in basin to seal chamber. Chamber is also provided with heads for spraying the liquid into the advancing gas to wet the same for a time sufficient to treat the gas. The passageway in outlet wall passes the gas from the treatment chamber into and below a second, higher level of solution in basin and the gas advances to the atomsphere.

  11. Quality user support: Supporting quality users

    SciTech Connect

    Woolley, T.C.

    1994-12-31

    During the past decade, fundamental changes have occurred in technical computing in the oil industry. Technical computing systems have moved from local, fragmented quantity, to global, integrated, quality. The compute power available to the average geoscientist at his desktop has grown exponentially. Technical computing applications have increased in integration and complexity. At the same time, there has been a significant change in the work force due to the pressures of restructuring, and the increased focus on international opportunities. The profile of the user of technical computing resources has changed. Users are generally more mature, knowledgeable, and team oriented than their predecessors. In the 1990s, computer literacy is a requirement. This paper describes the steps taken by Oryx Energy Company to address the problems and opportunities created by the explosive growth in computing power and needs, coupled with the contraction of the business. A successful user support strategy will be described. Characteristics of the program include: (1) Client driven support; (2) Empowerment of highly skilled professionals to fill the support role; (3) Routine and ongoing modification to the support plan; (4) Utilization of the support assignment to create highly trained advocates on the line; (5) Integration of the support role to the reservoir management team. Results of the plan include a highly trained work force, stakeholder teams that include support personnel, and global support from a centralized support organization.

  12. SLD liquid argon calorimeter

    SciTech Connect

    Vella, E.; SLD Collaboration

    1992-10-01

    The liquid argon calorimeter (LAC) of the SLD detector is a parallel plate -- liquid argon sampling calorimeter, used to measure particle energies in Z{sup 0} decays at the Stanford Linear Collider. The LAC module design is based on a unique projective tower structure, in which lead plates and segmented lead tiles serve both as absorbers and electrodes. The LAC front end electronics incorporates several novel features, including extensive multiplexing and optical fiber readout, which take advantage of the low SLC beam crossing frequency. The operational performance of the LAC during the recently completed SLD physics run (which recorded over 10,000 Z{sup 0} events) is discussed.

  13. SLD liquid argon calorimeter

    SciTech Connect

    Vella, E.

    1992-10-01

    The liquid argon calorimeter (LAC) of the SLD detector is a parallel plate -- liquid argon sampling calorimeter, used to measure particle energies in Z[sup 0] decays at the Stanford Linear Collider. The LAC module design is based on a unique projective tower structure, in which lead plates and segmented lead tiles serve both as absorbers and electrodes. The LAC front end electronics incorporates several novel features, including extensive multiplexing and optical fiber readout, which take advantage of the low SLC beam crossing frequency. The operational performance of the LAC during the recently completed SLD physics run (which recorded over 10,000 Z[sup 0] events) is discussed.

  14. Liquid sheet radiator

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L.; White, K. Alan, III

    1987-01-01

    A new external flow radiator concept, the liquid sheet radiator (LSR), is introduced. The LSR sheet flow is described and an expression for the length/width (l/w), ratio is presented. A linear dependence of l/w on velocity is predicted that agrees with experimental results. Specific power for the LSR is calculated and is found to be nearly the same as the specific power of a liquid droplet radiator, (LDR). Several sheet thicknesses and widths were experimentally investigated. In no case was the flow found to be unstable.

  15. Monogroove heat pipe design: Insulated liquid channel with bridging wick

    NASA Astrophysics Data System (ADS)

    Alario, J. P.; Brown, R. F.; Kosson, R. L.

    1985-05-01

    A screen mesh artery supported concentrically within the evaporator section of a heat pipe liquid channel retains liquid in the channel. Continued and uniform liquid feed to the heat pipe evaporation section (20) during periods of excessive heat transfer is assured. The overall design provides high evaporation and condensation film coefficients for the working fluid by means of the circumferential grooves in the walls of the vapor channel, while not interfering with the overall heat transport capability of the axial groove. The design has particular utility in zero-g environments.

  16. Flexible liquid metal-filled metamaterial absorber on polydimethylsiloxane (PDMS).

    PubMed

    Ling, Kenyu; Kim, Kyeoungseob; Lim, Sungjoon

    2015-08-10

    In this paper, we propose a novel flexible metamaterial (MM) absorber. The conductive pattern consists of liquid metal eutectic gallium indium alloy (EGaIn) enclosed in elastomeric microfluidic channels. Polydimethylsiloxane (PDMS) material is used as a supporting substrate. The proposed MM absorber is flexible because of its liquid metal and PDMS substrate. Numerical simulations and experimental results are presented when the microfluidic channels are filled with liquid metal. In order to evaluate the proposed MM absorber's performance, the fabricated absorber prototype is tested with rectangular waveguides. Almost perfect absorptivity is achieved at a resonant frequency of 8.22 GHz. PMID:26367985

  17. Monogroove heat pipe design: Insulated liquid channel with bridging wick

    NASA Technical Reports Server (NTRS)

    Alario, J. P.; Brown, R. F.; Kosson, R. L. (Inventor)

    1985-01-01

    A screen mesh artery supported concentrically within the evaporator section of a heat pipe liquid channel retains liquid in the channel. Continued and uniform liquid feed to the heat pipe evaporation section (20) during periods of excessive heat transfer is assured. The overall design provides high evaporation and condensation film coefficients for the working fluid by means of the circumferential grooves in the walls of the vapor channel, while not interfering with the overall heat transport capability of the axial groove. The design has particular utility in zero-g environments.

  18. Apparatus and method for electrochemical modification of liquids

    SciTech Connect

    James, Patrick I

    2015-04-21

    An apparatus for electrochemical modification of liquid streams employing an electrolytic cell which includes an anode compartment defined by an anode structure where oxidation is effected, containing a liquid electrolyte anolyte, and a cathode compartment defined by a cathode structure where reduction is effected containing a liquid electrolyte catholyte. In addition, the electrolytic cell includes at least one additional compartment arranged at least partially between the anode compartment and the cathode compartment and separated from the anode compartment and the cathode compartment by a separator structure arranged to supports ionic conduction of current between the anode structure and the cathode structure.

  19. Radiography for a Shock-accelerated Liquid Layer

    SciTech Connect

    P. Meekunnasombat J.G. Oakley\\inst M.H. Anderson R. Bonazza

    2005-07-01

    This program supported the experimental study of the itneraction of planar shock waves with both solid structures (a single cylinder or a bank of cylinders) and single and multiple liquid layers. Objectives of the study included: characterization of the shock refraction patterns; measurements of the impulsive loading of the solid structures; observation of the response of the liquid layers to shock acceleration; assessment of the shock-mitigation effects of single and multiple liquid layers. The uploaded paper is intended as a final report for the entire funding period. The poster described in the paper won the Best Poster Award at the 25 International Symposium on Shock Waves.

  20. Surface Chemistry and Properties of Oxides as Catalyst Supports

    SciTech Connect

    DeBusk, Melanie Moses; Narula, Chaitanya Kumar; Contescu, Cristian I

    2015-01-01

    Heterogeneous catalysis relies on metal-oxides as supports for the catalysts. Catalyst supports are an indispensable component of most heterogeneous catalysts, but the role of the support is often minimized in light of the one played by the catalytically active species it supports. The active species of supported catalysts are located on the surface of the support where their contact with liquid or gas phase reactants will be greatest. Considering that support plays a major role in distribution and stability of active species, the absorption and retention of reactive species, and in some cases in catalytic reaction, the properties and chemistry that can occur at the surface of an oxide support are important for understanding their impact on the activity of a supported catalyst. This chapter examines this rich surface chemistry and properties of oxides used as catalyst supports, and explores the influence of their interaction with the active species.

  1. Autothermal Processing of Renewable Liquids

    NASA Astrophysics Data System (ADS)

    Kruger, Jacob Scott

    The vast majority of petrochemicals are synthesized from just six building block molecules, but current feedstocks are an unsustainable resource with negative externalities. Biomass represents a potentially sustainable feedstock, but needs densification, preferably to a liquid form, to be a suitable replacement. Fermentation to butanol and pyrolysis to bio-oil are two promising liquid intermediates. Catalytic partial oxidation (CPO) of the liquid intermediates over noble metal catalysts, which converts the liquids primarily into syngas and light olefins, is a promising technique for processing densified biomass. The study of liquids at high temperatures requires consideration of a range of complex phenomena, including boiling behavior on hot surfaces, reactions of the feed molecules at high temperatures and on catalyst surfaces, and interactions of impurities in the liquid with the catalyst. Chapter 2 deals with the behavior of the transient liquid that forms when cellulose, a major constituent of biomass, is pyrolized. Fast photography experiments and numerical simulations are performed to show that the aerosols formed in the boiling of this liquid are capable of transporting nonvolatile fragments of biomass intact into the gas phase. These nonvolatile fragments have significant implications in the storage and downstream processing of bio-oil. Some of the behavior of bio-oil at high temperature may also be explained by the variety of molecules in the liquid. Many different functional groups are present, each with its own set of chemical reactions in combustion, pyrolysis, and partial oxidation on a metal catalyst. Chapters 3 and 4 investigate these reactions through a survey of two-carbon surrogates of the functional group classes found in bio-oil. Chapter 3 examines reactions occuring in the complete CPO system over Pt and Rh catalysts, and in the complete system absent O 2. The selectivity data from each molecule and the surface science literature of each molecule are used to propose a reaction mechanism over the catalyst surface. Chapter 4 investigates the reactions that may be occurring in the gas phase and over the alpha-Al2O3 foam monolith support. Significant gas-phase chemistry is likely present in the autothermal reactor, although different temperature gradients between the autothermal reactions and the externally heated tube makes quantification of the amount of homogeneous chemistry in the autothermal system impossible. The alpha-Al2O 3 support may serve as a heat transfer medium and radical quencher (due to its foam structure with small-diameter pores), but not likely acid catalysis, as selectivity to dehydration products was similar both with and without the foam support. Because butanol is another promising liquid intermediate in biomass processing, a series of experiments with butanol in an CPO reactor was also carried out. Chapter 5 compares the four butanol isomers in a CPO reactor over Pt, PtCe, Rh, and RhCe catalysts. The reactivity of tert-butanol was as high or higher than the other alcohols, indicating that the lack of a carbonyl decomposition path does not necessarily in uence the reactivity of the molecule. Rather, the reactivity appeared to be more a function of the initial pyrolysis temperature of the alcohol. Thus, much of the initial chemistry of the higher alcohols in a CPO reactor may be homogeneous. The main function of the catalyst may be to decompose the intermediate carbonyls and alkenes to syngas. To that end, the PtCe had significantly lower reforming activity than the other catalysts, evidenced by the lower selectivity to CO and H2 and generally higher temperatures. Selectivity to syngas and light olefins was high and tunable depending on feed ratios, indicating the potential of CPO to provide petrochemical building blocks from butanol. Chapter 6 combines CPO with a water-gas shift (WGS) stage and investigates the addition of steam to isobutanol for the production of a high-purity H2 stream. A RhCe catalyst was used in the CPO stage to convert 100% of the isobutanol feed to primarily equilibrium products, although a non-negligible fraction of intermediate isobutryaldehyde, propylene and isobutene. The use of a PtCe catalyst directly downstream allowed the incorporation of a high-temperature WGS stage with no external heat addition. Concentration of CO in the exit stream ≤ 3%, and H2 selectivity ≥ 100% (based on H from isobutanol) was achieved, similar to industrial high-temperature WGS operations. Additionally, the use of a PtCe WGS catalyst allowed conversion of intermediate products remaining from the CPO stage, indicating the robustness of the CPO-WGS system. Finally, because any feedstock intended to produce petrochemical feedstocks will contain impurities, Chapter 7 investigates the durability of a RhCe catalyst over several hundred hours with CPO of food-grade glycerol. This feedstock contains ppm levels of Fe and several other impurities. Despite several perturbations to the system and the addition of impurity levels comparable to catalyst loading by the end of the test, the catalyst maintained 100% conversion of glycerol to equilibrium products throughout the experiment, although some loss of WGS activity was observed. In Chapter 8, several experiments are proposed to strengthen the conclusions of the experiments described in the previous chapters, including co-feeding of radicalscavenging molecules, in-situ spectroscopic studies, and mechanism validation with the current data. Further study of boiling phenomena is also proposed, and some preliminary results are presented. Additionally, integration of photochemistry into a CPO reactor is proposed as a method of improving catalyst durability for processing particularly recalcitrant feedstocks. The ability of CPO to handle high-moisture feedstocks may allow for its use in processing aquatic biomass; a potential design for a photobioreactor for algae cultivation with integration of a CPO reactor is described. Finally, the study of ethanol conversion to butanol through a Guerbet-type reaction is proposed. A Guerbet stage would function particularly well downstream of a CPO reactor because it requires heat, dehydrogenated alcohols, and H 2 addition. Although a comprehensive understanding of the phenomena occuring in a CPO reactor is far from available, the diversity of applications in which sustainably produced syngas and heat find use suggests that CPO reaction engineering is an important area of research. This thesis offers preliminary insight into some of the phenomena and applications of catalytic partial oxidation.

  2. Turbine meters for liquid measurement

    SciTech Connect

    Wass, D.J.; Allen, C.R.

    1995-12-01

    Liquid turbine meters operate in response to fundamental engineering principles, Operation with a single moving part produces excellent longevity and reliability. Liquid turbine meters display wide rangeability, high accuracy, excellent repeatability, low pressure drop and moderate cost. Liquid turbine meters may be applied to many different fluids with different physical properties and corrosive tendencies. The marriage of liquid turbine meters to electronic instruments allows instantaneous flow calculations and produces the flexibility to display data, store data, transmit data in the most convenient form. Liquid turbine meters should be the first flow measurement instrument considered for liquid measurement applications.

  3. Liquid metal fuel combustion mechanics

    NASA Astrophysics Data System (ADS)

    Duvvuri, Tirumalesa

    1990-07-01

    The modeling of the droplet formation at the gas/liquid boundary interface of a gaseous jet injected into a liquid metal bath and the turbulent mixing of the resultant two-phase (gas/liquid) mixture is presented as a preliminary to the analysis of the liquid metal fuel combustion problem. The model is used to predict velocity and liquid droplet fraction distributions across the mixing zone and along the centerline of the jet. These results show that the distribution of the liquid fuel droplets peaks away from the region of maximum oxidizer concentrations.

  4. Flexible Learning: Support Issues for Support Staff

    ERIC Educational Resources Information Center

    Winter, Rosamund

    2002-01-01

    The move to providing flexible delivery of university subjects and courses urged by government policy raises a number of issues for support staff. Whatever "flexible learning" might mean, there are hardware, software, training and attitudinal issues which are central to the work of support staff. This paper will address some of the issues for

  5. Mixed Stationary Liquid Phases for Gas-Liquid Chromatography.

    ERIC Educational Resources Information Center

    Koury, Albert M.; Parcher, Jon F.

    1979-01-01

    Describes a laboratory technique for use in an undergraduate instrumental analysis course that, using the interpretation of window diagrams, prepares a mixed liquid phase column for gas-liquid chromatography. A detailed procedure is provided. (BT)

  6. 138. LIQUID NITROGEN INSTRUMENT PANEL ON EAST WALL OF LIQUID ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    138. LIQUID NITROGEN INSTRUMENT PANEL ON EAST WALL OF LIQUID NITROGEN CONTROL ROOM (115), LSB (BLDG. 770) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  7. RF gauging efforts with liquid hydrogen and liquid oxygen as applicable to subcritical space vehicle systems

    NASA Technical Reports Server (NTRS)

    Thompson, H. E.; Ott, W.; Stanley, N.

    1974-01-01

    The RF gauging concept is based on the interaction between a fluid dielectric medium in an enclosed metallic cavity and electromagnetic fields set up within that cavity. In RF gauging systems, the fundamental measurement relies on the interpretation of changes in the resonant RF frequencies of an enclosed tank as the mass of the propellant contained in the tank is changed. In addition to a discussion of the basic principles of operation of these systems, the study presents a description of the current breadboard implementation with typical test arrangements, along with supporting test data. The experimental testing of the RF gauging technique for liquid cryogen mass gauging indicates that this technique is a feasible approach to liquid oxygen and liquid hydrogen gauging under all attitude or reduced gravity environments.

  8. Emulsions Containing Perfluorocarbon Support Cell Cultures

    NASA Technical Reports Server (NTRS)

    Ju, Lu-Kwang; Lee, Jaw Fang; Armiger, William B.

    1990-01-01

    Addition of emulsion containing perfluorocarbon liquid to aqueous cell-culture medium increases capacity of medium to support mammalian cells. FC-40 Fluorinert (or equivalent) - increases average density of medium so approximately equal to that of cells. Cells stay suspended in medium without mechanical stirring, which damages them. Increases density enough to prevent cells from setting, and increases viscosity of medium so oxygen bubbled through it and nutrients stirred in with less damage to delicate cells.

  9. The SNS Liquids Reflectometer

    SciTech Connect

    Ankner, John Francis; Tao, Xiaodong; Halbert, Candice E; Browning, Jim; Kilbey, II, S Michael; Swader, Onome A; Dadmun, Mark D; Kharlampieva, Dr. Eugenia; Sukhishvili, Prof. Svetlana A.

    2008-01-01

    The SNS Liquids Reflectometer [1], installed as one of the first instruments at the Spallation Neutron Source, has now been functional for more than a year. This instrument is designed to view liquid and solid surfaces in specular, off specular, and near-surface small angle scattering geometries. The guide system supplies 2 {angstrom} < {angstrom} < 16.5 {angstrom} neutrons at vertical incident angles ranging from 0{sup o} < {alpha}{sub i} < 5.5{sup o} for free liquid surfaces and up to 45{sup o} for solid surfaces. Three bandwidth choppers, synchronized with the spallation source and operating at 15-60 Hz, provide neutrons in bandwidths ranging from 3.5-14 {angstrom} at a fixed incident angle onto a sample. The sample stage enables all of the motions necessary for positioning liquid and solid surfaces, while the detector arm directs a position-sensitive detector to view the sample at specular or off specular angles up to 90{sup o} and can scan out of the specular plane by up to 30{sup o}.

  10. Liquid propellant densification

    NASA Technical Reports Server (NTRS)

    Lak, Tibor I. (Inventor); Petrilla, Steve P. (Inventor); Lozano, Martin E. (Inventor)

    1997-01-01

    Super cooling the cryogenic liquid propellant in a vehicle propellant tank densities the propellant allowing the vehicle propellant tank to carry more fuel in the same volume tank while lowering the vapor pressure and thus the tank operating pressure. Lowering the tank operating pressure reduces the stress and therefore allows the walls of the tank to be thinner. Both the smaller tank volume and thinner tank wall results in an overall smaller and lighter vehicle with increased payload capability. The cryogenic propellant can be supercooled well below the normal boiling point temperature level by transporting the liquid propellant from the vehicle tanks to a ground based cooling unit which utilizes a combination of heat exchanger and compressor. The compressor lowers the coolant fluid bath pressure resulting in a low temperature boiling liquid which is subsequently used to cool the recirculating liquid. The cooled propellant is then returned to the vehicle propellant tank. In addition to reducing the vehicle size and weight the invention also allows location of the vent valve on the ground, elimination of on-board recirculation pumps or bleed systems, smaller and lighter engine pumps and valves, lighter and more stable ullage gas, and significant reduction in tank fill operation. All of these mentioned attributes provide lower vehicle weight and cost.

  11. Thermoelectricity in liquid crystals

    NASA Astrophysics Data System (ADS)

    Mohd Said, Suhana; Nordin, Abdul Rahman; Abdullah, Norbani; Balamurugan, S.

    2015-09-01

    The thermoelectric effect, also known as the Seebeck effect, describes the conversion of a temperature gradient into electricity. A Figure of Merit (ZT) is used to describe the thermoelectric ability of a material. It is directly dependent on its Seebeck coefficient and electrical conductivity, and inversely dependent on its thermal conductivity. There is usually a compromise between these parameters, which limit the performance of thermoelectric materials. The current achievement for ZT~2.2 falls short of the expected threshold of ZT=3 to allow its viability in commercial applications. In recent times, advances in organic thermoelectrics been significant, improving by over 3 orders of magnitude over a period of about 10 years. Liquid crystals are newly investigated as candidate thermoelectric materials, given their low thermal conductivity, inherent ordering, and in some cases, reasonable electrical conductivity. In this work the thermoelectric behaviour of a discotic liquid crystal, is discussed. The DLC was filled into cells coated with a charge injector, and an alignment of the columnar axis perpendicular to the substrate was allowed to form. This thermoelectric behavior can be correlated to the order-disorder transition. A reasonable thermoelectric power in the liquid crystal temperature regime was noted. In summary, thermoelectric liquid crystals may have the potential to be utilised in flexible devices, as a standalone power source.

  12. Liquid laser cavities

    NASA Technical Reports Server (NTRS)

    Bjorklund, S.; Filipescu, N.; Kellermeyer, G. L.; Mc Avoy, N.

    1969-01-01

    Liquid laser cavities have plenum chambers at the ends of the capillary cell which are terminated in transparent optical flats. By use of these cavities, several new europium chelates and a terbium chelate can provide laser action in solution at room temperature.

  13. LIQUID WASTE COMPOSTING

    EPA Science Inventory

    This research project was conducted at the Chesapeake and Ohio Canal National Historical Park to examine the feasibility of adapting and using the sludge composting technique to compost liquid waste collected in the National Parks. This study evaluated the composting of two probl...

  14. Microplasmas in liquids

    NASA Astrophysics Data System (ADS)

    Staack, David

    2013-09-01

    Plasma discharges from 1 ? m to 10 ? m in size can be generated in a variety of liquids by the use of nanosecond duration high voltage pulses of low energy. Through a variety of high temporal and spatial resolution diagnostic the plasma discharge formation, growth and properties are studied. Experiments reveal the plasma is confined inside of a small lower density region, or bubble, in the fluid. This bubble is generated commensurate with the plasma formation and the stability and rate of bubble growth is input energy and medium dependent. Emission spectroscopy indicates the microscale plasmas to be non-equilibrium but only when the lowest energy, and smallest, discharges are generated. The non-equilibrium and high surface to volume ratio of the microplasmas offers a unique set of liquid phase plasma chemistries. Various schema for generating both highly localized and volumetrically distributed non-equilibrium microplasmas in liquids are presented. When applied to the reforming of fuels and oils the advantages of the non-equilibrium discharge in liquid regime lead to more control over the product compositions.

  15. ELECTRONS IN NONPOLAR LIQUIDS.

    SciTech Connect

    HOLROYD,R.A.

    2002-10-22

    Excess electrons can be introduced into liquids by absorption of high energy radiation, by photoionization, or by photoinjection from metal surfaces. The electron's chemical and physical properties can then be measured, but this requires that the electrons remain free. That is, the liquid must be sufficiently free of electron attaching impurities for these studies. The drift mobility as well as other transport properties of the electron are discussed here as well as electron reactions, free-ion yields and energy levels, Ionization processes typically produce electrons with excess kinetic energy. In liquids during thermalization, where this excess energy is lost to bath molecules, the electrons travel some distance from their geminate positive ions. In general the electrons at this point are still within the coulombic field of their geminate ions and a large fraction of the electrons recombine. However, some electrons escape recombination and the yield that escapes to become free electrons and ions is termed G{sub fi}. Reported values of G{sub fi} for molecular liquids range from 0.05 to 1.1 per 100 eV of energy absorbed. The reasons for this 20-fold range of yields are discussed here.

  16. Diet - clear liquid

    MedlinePLUS

    ... the important fluids, salts, and minerals that you need for energy. Eating only a clear liquid diet gives you enough nutrition for 3 to 4 days. It is safe for people with diabetes, but only for a short time when they are followed closely by their doctor.

  17. Clean room wiping liquids

    SciTech Connect

    Harding, W.B.

    1991-12-01

    A water-based liquid containing isopropyl alcohol, ammonium hydroxide, and surfactants was developed to replace 1,1,2-trichlorotrifluoroethane for the dampening of clean room wiping cloths used to wipe clean benches, clean room equipment, and latex finger cots and gloves.

  18. Ferroelectric liquid crystal display

    NASA Technical Reports Server (NTRS)

    York, Paul K. (Inventor)

    1977-01-01

    A ferroelectric liquid crystal display device employs capacitance spoiling layers to minimize unneeded capacitances created by crossovers of X and Y address lines and to accurately define desired capacitances. The spoiler layers comprise low dielectric constant layers which space electrodes from the ferroelectric at crossover points where capacitance is not needed for device operation.

  19. Liquid Rocket Engine Testing

    NASA Technical Reports Server (NTRS)

    Rahman, Shamim

    2005-01-01

    Comprehensive Liquid Rocket Engine testing is essential to risk reduction for Space Flight. Test capability represents significant national investments in expertise and infrastructure. Historical experience underpins current test capabilities. Test facilities continually seek proactive alignment with national space development goals and objectives including government and commercial sectors.

  20. Properties of Liquid Plutonium

    SciTech Connect

    Freibert, Franz J.; Mitchell, Jeremy N.; Schwartz, Daniel S.; Saleh, Tarik A.; Migliori, Albert

    2012-08-02

    Unalloyed polycrystalline Pu displays extreme thermal expansion behavior, i.e., {alpha} {yields} {beta} {yields} {gamma} {yields} {delta} increases by 25% in volume and {delta} {yields} {var_epsilon} {yields} liquid decreases by 4.5% in volume. Thus, making it difficult to measure density into the liquid state. Dilatometer outfitted with CaF molten metal cell offers a proven capability to measure thermal expansion in molten metals, but has yet to be proven for Pu. Historic data from the liquid nuclear fuels program will prove extremely useful as a guide to future measurements. 3.3at% Ga changes Pu molten metal properties: 50% increase in viscosity and {approx}3% decrease in density. Fe may decrease the density by a small amount assuming an averaging of densities for Pu-Ga and Pu-Fe liquids. More recent Boivineau (2009) work needs some interpretation, but technique is being employed in (U,Pu)O{sub 2} nuclear fuels program (Pu Futures, 2012).

  1. Coalescence of Liquid Drops

    NASA Technical Reports Server (NTRS)

    Yao, Wei-Jun

    2003-01-01

    When two liquid drops come into contact, a neck forms between them and grows rapidly. We are interested in the very early stage of the coalescence process, which can be characterized by the time dependence of the radius of the neck. The functional dependence of the size of the neck on time depends on the properties of the liquid. Experimentally, we are investigating a liquid in Stokes flow regime where the viscosity provides the principal retarding force to the surface tension. Recently, it has been predicted that the neck radius should change as t ln|t| in this regime. Theoretically, we have studied the situation when the velocity at each point on the surface is proportional to the local curvature and directed normal to the surface. This is the case that should be applicable to superfluid helium at low temperature when the mean free path of the thermal excitations are comparable to the size of liquid drops. For this system, the radius of the neck is found to be proportional to t(sup 1/3). We are able to find a simple expression for the shape of the interface in the vicinity of the neck.

  2. Liquid rocket valve assemblies

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The design and operating characteristics of valve assemblies used in liquid propellant rocket engines are discussed. The subjects considered are as follows: (1) valve selection parameters, (2) major design aspects, (3) design integration of valve subassemblies, and (4) assembly of components and functional tests. Information is provided on engine, stage, and spacecraft checkout procedures.

  3. Liquid rocket valve components

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A monograph on valves for use with liquid rocket propellant engines is presented. The configurations of the various types of valves are described and illustrated. Design criteria and recommended practices for the various valves are explained. Tables of data are included to show the chief features of valve components in use on operational vehicles.

  4. High CO2 solubility, permeability and selectivity in ionic liquids with the tetracyanoborate anion

    SciTech Connect

    Mahurin, SM; Hillesheim, PC; Yeary, JS; Jiang, DE; Dai, S

    2012-01-01

    Five different ionic liquids containing the tetracyanoborate anion were synthesized and evaluated for CO2 separation performance. Measured CO2 solubility values were exceptionally high compared to analogous ionic liquids with different anions and ranged from 0.128 mol L-1 atm(-1) to 0.148 mol L-1 atm(-1). In addition, CO2 permeability and CO2/N-2 selectivity values were measured using a supported ionic liquid membrane architecture and the separations performance of the ionic liquid membranes exceeded the Robeson upper bound. These results establish the distinct potential of ionic liquids with the tetracyanoborate, [B(CN)(4)], anion for the separation of CO2.

  5. Nutritional support of hospitalized patients.

    PubMed

    Donoghue, S

    1989-05-01

    Effective nutritional support requires sound knowledge of both basic and clinical nutrition of dogs and cats as well as familiarity with products and delivery systems. Case management includes assessment of nutritional status and estimation of fuel sources. Most starved or stressed patients use fatty acids for over 70 per cent kcalME and protein for over 20 per cent kcalME. Approximate kcal needs are calculated from maintenance energy equations. Most patients respond best to enteral nutrition. Meat-based pet foods, liquid enteral products, and nutrient modules are offered in slurries or are tube-fed. Management includes careful monitoring of patients and gradual transitions to diets with more complex nutrient sources. PMID:2658286

  6. Heat exchanger support apparatus in a fluidized bed

    SciTech Connect

    Lawton, C.W.

    1982-05-25

    A heat exchanger is mounted in the upper portion of a fluidized combusting bed for the control of the temperature of the bed. A support, made up of tubes, is extended from the perforated plate of the fluidized bed up to the heat exchanger. The tubular support framework for the heat exchanger has liquid circulated there through to prevent deterioration of the support. 2 figs.

  7. Models of liquid metal corrosion

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Hosemann, P.; Maloy, S.

    2010-09-01

    In the present study, models for liquid metal corrosion are reviewed and their applications in nuclear reactor engineering are discussed. The paper presents mathematical analysis of liquid metal corrosion, including species transport in solid steels, in flowing liquid metals, and mass exchange at liquid/solid interface. The survey illustrates the mechanisms of the liquid metal corrosion and sets up a system to calculate the corrosion rate and to study the corrosion species distributions in the solid and liquid metal/alloys. Both light liquid metal/alloy (sodium and sodium-potassium) and heavy liquid metal/alloy (liquid lead and lead-bismuth) are considered. Oxygen effects on liquid metal corrosion are also discussed. For liquid sodium and sodium-potassium the corrosion rate increases with increasing oxygen concentration, while for liquid lead and lead-bismuth it is reasonable to produce a protective oxide layer using an oxygen control technique which can mitigate the corrosion rate significantly. Finally, the corrosion-oxidation interaction in liquid lead and lead-bismuth are discussed.

  8. Coal preparation process using true-heavy-liquid separation

    SciTech Connect

    Baltich, L.K.; Malhotra, D.

    1990-12-20

    The Pittsburgh Energy Technology Center (PETC) is supporting work to develop advanced fine-coal cleaning processes including the exploitation of differences in specific gravity through the use of heavy-liquid media in hydrocyclones. The true-heavy-liquid media used for this program are solutions of sulfuric acid (H{sub 2}SO{sub 4}) and water. This concept takes advantage of the miscibility of the acid water to produce a range of heavy liquids up to a specific gravity of 1.84 for pure sulfuric acid. The main objective of this research program was to develop a true-heavy-liquid separation process to clean ultrafine coal using smelter-guide sulfuric acid. Three bituminous coals and one subbituminous coal were selected for testing. In general, single-stage true-heavy-liquid hydrocyclone process demonstrated similar performance characteristics to heavy-media separation processes under study by other investigators. True-heavy-liquid media has the advantage of allowing additional separation steps at other specific gravities for cleaning and scavenging without the introduction of another heavy liquid to the flowsheet. In addition, sulfuric acid is inorganic and can be neutralized and disposed of without the toxicity problems associated with the other type of heavy liquids under consideration. Preliminary economics analysis indicates that the cost for sulfuric acid makeup to the process may be prohibitive. 4 refs., 11 figs., 61 tabs.

  9. Child Support Report, 2001.

    ERIC Educational Resources Information Center

    Sharman, Phil, Ed.

    2001-01-01

    This document comprises the 12 issues for 2001 of the "Child Support Report," which explores problems related to child support enforcement, reports on federal and state government child support enforcement initiatives, and summarizes research related to child support. Featured regularly are editorials and information on events of interest and

  10. Child Support Report, 2002.

    ERIC Educational Resources Information Center

    Sharman, Phil, Ed.

    2002-01-01

    This document comprises the 12 issues for 2002 of the Child Support Report, which explores problems related to child support enforcement, reports on federal and state government child support enforcement initiatives, and summarizes research related to child support. Featured regularly are editorials and information on events of interest and

  11. Flowcharts as Technical Support

    ERIC Educational Resources Information Center

    Caudill, Jason

    2007-01-01

    Any time technology is employed in an organization there is a need to provide support for the users. Such support usually needs to be offered at the location where users are trying to access the technological resources. More often than not, the user who needs the support wants to get the support immediately, not at some point in the future after a…

  12. Child Support Report, 1998.

    ERIC Educational Resources Information Center

    Sharman, Phil, Ed.

    1998-01-01

    This document is comprised of the 12 monthly issues of the 1998 "Child Support Report," which explores problems related to child support enforcement, reports on federal and state government child support enforcement initiatives, and summarizes research related to child support. Editorials and information on events and conferences of interest and

  13. Child Support Report, 2000.

    ERIC Educational Resources Information Center

    Sharman, Phil, Ed.

    2000-01-01

    This document comprises the 12 issues for 2000 of the "Child Support Report," which explores problems related to child support enforcement, reports on federal and state government child support enforcement initiatives, and summarizes research related to child support. Featured regularly are editorials and information on events of interest and

  14. Child Support Report, 1999.

    ERIC Educational Resources Information Center

    Sharman, Phil, Ed.

    1999-01-01

    This document comprises the 12 issues for 1999 of the "Child Support Report," which explores problems related to child support enforcement, reports on federal and state government child support enforcement initiatives, and summarizes research related to child support. Editorials and information on events and conferences of interest and funding…

  15. Child Support Report, 1997.

    ERIC Educational Resources Information Center

    Sharman, Phil, Ed.

    1997-01-01

    This document consists of the twelve issues of "Child Support Report" newsletter published during 1997. Monthly issues typically explore problems related to child support enforcement, report on federal and state government child support enforcement initiatives, and summarize research related to child support. Editorials and information on events

  16. Liquid crystalline dendrimers.

    PubMed

    Donnio, Bertrand; Buathong, Saïwan; Bury, Izabela; Guillon, Daniel

    2007-09-01

    In recent years, there has been an increasing interest in the field of liquid crystalline dendrimers. Such a fast development is, among other things, driven by the multiple possibilities offered by combining the mesomorphic properties of single mesogenic subunits with the supermolecular and versatile architectures of dendrimers to yield a new class of highly functional materials. The induction and the control of the mesomorphic properties (phase type and stability) in dendrimers can be achieved by a dedicated molecular design which depends on the chemical nature and structure of both the functional groups and the dendritic matrix. In particular, the intrinsic connectivity of the dendrimer such as the multivalency of the focal core and the multiplicity of the branches, both controlling the geometrical rate of growth, or the dendritic generation, plays a crucial role and influences at various stages the subtle relationships between the supermolecular structure and the mesophase structure and stability. In this critical review article, an account of the various types of dendritic systems that form liquid-crystalline mesophases along with a description of the self-organization of representative case-study supermolecules into liquid crystalline mesophases will be discussed. Some basics of thermotropic liquid crystals and dendrimers will be given in the introduction. Then, in the following sections, selected examples including side-chain, main-chain, fullerodendrimers, shape-persistent dendrimers, supramolecular dendromesogens and metallodendrimers, as representative families of LC dendrimers, will be described. In the conclusion some further developments will be highlighted. This review will not cover liquid crystalline hyperbranched and dendronized polymers that might be considered as being somehow less structurally "perfect". PMID:17660881

  17. 3-Methylpiperidinium ionic liquids.

    PubMed

    Belhocine, Tayeb; Forsyth, Stewart A; Gunaratne, H Q Nimal; Nieuwenhuyzen, Mark; Nockemann, Peter; Puga, Alberto V; Seddon, Kenneth R; Srinivasan, Geetha; Whiston, Keith

    2015-04-28

    A wide range of room temperature ionic liquids based on the 3-methylpiperdinium cation core were produced from 3-methylpiperidine, which is a derivative of DYTEK A amine. First, reaction with 1-bromoalkanes or 1-bromoalkoxyalkanes generated the corresponding tertiary amines (Rm?pip, R = alkyl or alkoxyalkyl); further quaternisation reactions with the appropriate methylating agents yielded the quaternary [Rmm?pip]X salts (X(-) = I(-), [CF3CO2](-) or [OTf](-); Tf = -SO2CF3), and [Rmm?pip][NTf2] were prepared by anion metathesis from the corresponding iodides. All [NTf2](-) salts are liquids at room temperature. [Rmm?pip]X (X(-) = I(-), [CF3CO2](-) or [OTf](-)) are low-melting solids when R = alkyl, but room temperature liquids upon introduction of ether functionalities on R. Neither of the 3-methylpiperdinium ionic liquids showed any signs of crystallisation, even well below 0 C. Some related non-C-substituted piperidinium and pyrrolidinium analogues were prepared and studied for comparison. Crystal structures of 1-hexyl-1,3-dimethylpiperidinium tetraphenylborate, 1-butyl-3-methylpiperidinium bromide, 1-(2-methoxyethyl)-1-methylpiperidinium chloride and 1-(2-methoxyethyl)-1-methylpyrrolidinium bromide are reported. Extensive structural and physical data are collected and compared to literature data, with special emphasis on the systematic study of the cation ring size and/or asymmetry effects on density, viscosity and ionic conductivity, allowing general trends to be outlined. Cyclic voltammetry shows that 3-methylpiperidinium ionic liquids, similarly to azepanium, piperidinium or pyrrolidinium counterparts, are extremely electrochemically stable; the portfolio of useful alternatives for safe and high-performing electrolytes is thus greatly extended. PMID:25669485

  18. Rockets using Liquid Oxygen

    NASA Technical Reports Server (NTRS)

    Busemann, Adolf

    1947-01-01

    It is my task to discuss rocket propulsion using liquid oxygen and my treatment must be highly condensed for the ideas and experiments pertaining to this classic type of rocket are so numerous that one could occupy a whole morning with a detailed presentation. First, with regard to oxygen itself as compared with competing oxygen carriers, it is known that the liquid state of oxygen, in spite of the low boiling point, is more advantageous than the gaseous form of oxygen in pressure tanks, therefore only liquid oxygen need be compared with the oxygen carriers. The advantages of liquid oxygen are absolute purity and unlimited availability at relatively small cost in energy. The disadvantages are those arising from the impossibility of absolute isolation from heat; consequently, allowance must always be made for a certain degree of vaporization and only vented vessels can be used for storage and transportation. This necessity alone eliminates many fields of application, for example, at the front lines. In addition, liquid oxygen has a lower specific weight than other oxygen carriers, therefore many accessories become relatively larger and heavier in the case of an oxygen rocket, for example, the supply tanks and the pumps. The advantages thus become effective only in those cases where definitely scheduled operation and a large ground organization are possible and when the flight requires a great concentration of energy relative to weight. With the aim of brevity, a diagram of an oxygen rocket will be presented and the problem of various component parts that receive particularly thorough investigation in this classic case but which are also often applicable to other rocket types will be referred to.

  19. Liquid metal thermoacoustic engine

    SciTech Connect

    Swift, G.W.; Migliori, A.; Wheatley, J.C.

    1986-01-01

    We are studying a liquid metal thermoacoustic engine both theoretically and experimentally. This type of engine promises to produce large quantities of electrical energy from heat at modest efficiency with no moving parts. A sound wave is usually thought of as consisting of pressure oscillations, but always attendant to the pressure oscillation are temperature oscillations. The combination produces a rich variety of ''thermoacoustic'' effects. These effects are usually so small that they are never noticed in everyday life; nevertheless under the right circumstances they can be harnessed to produce powerful heat engines, heat pumps, and refrigerators. In our liquid metal thermoacoustic engine, heat flow from a high temperature source to a low temperature sink generates a high-amplitude standing acoustic wave in liquid sodium. This acoustic power is converted to electric power by a simple magnetohydrodynamic effect at the acoustic oscillation frequency. We have developed a detailed thermoacoustic theory applicable to this engine, and find that a reasonably designed liquid sodium engine operating between 700/sup 0/C and 100/sup 0/C should generate about 60 W/cm/sup 2/ of acoustic power at about 1/3 of Carnot's efficiency. Construction of a 3000 W-thermal laboratory model engine has just been completed, and we have exciting preliminary experimental results as of the time of preparation of this manuscript showing, basically, that the engine works. We have also designed and built a 1 kHz liquid sodium magnetohydrodynamic generator and have extensive measurements on it. It is now very well characterized both experimentally and theoretically. The first generator of its kind, it already converts acoustic power to electric power with 40% efficiency. 16 refs., 5 figs.

  20. Liquid Acquisition Device Design Sensitivity Study

    NASA Technical Reports Server (NTRS)

    VanDyke, M. K.; Hastings, L. J.

    2012-01-01

    In-space propulsion often necessitates the use of a capillary liquid acquisition device (LAD) to assure that gas-free liquid propellant is available to support engine restarts in microgravity. If a capillary screen-channel device is chosen, then the designer must determine the appropriate combination screen mesh and channel geometry. A screen mesh selection which results in the smallest LAD width when compared to any other screen candidate (for a constant length) is desirable; however, no best screen exists for all LAD design requirements. Flow rate, percent fill, and acceleration are the most influential drivers for determining screen widths. Increased flow rates and reduced percent fills increase the through-the-screen flow pressure losses, which drive the LAD to increased widths regardless of screen choice. Similarly, increased acceleration levels and corresponding liquid head pressures drive the screen mesh selection toward a higher bubble point (liquid retention capability). After ruling out some screens on the basis of acceleration requirements alone, candidates can be identified by examining screens with small flow-loss-to-bubble point ratios for a given condition (i.e., comparing screens at certain flow rates and fill levels). Within the same flow rate and fill level, the screen constants inertia resistance coefficient, void fraction, screen pore or opening diameter, and bubble point can become the driving forces in identifying the smaller flow-loss-to-bubble point ratios.

  1. Improved liquid-film electron stripper

    DOEpatents

    Gavin, B.F.

    1984-11-01

    An improved liquid-film electron stripper particularly for high intensity heavy ion beams which produces constant regenerated, stable, free-standing liquid films having an adjustable thickness between 0.3 to 0.05 microns. The improved electron stripper is basically composed of at least one high speed, rotating disc with a very sharp, precision-like, ground edge on one side of the disc's periphery and with highly polished, flat, radial surface adjacent the sharp edge. A fine stream of liquid, such as oil, impinges at a 90/sup 0/ angle adjacent the disc's sharp outer edge. Film terminators, located at a selected distance from the disc perimeter are positioned approximately perpendicular to the film. The terminators support, shape, and stretch the film and are arranged to assist in the prevention of liquid droplet formation by directing the collected film to a reservoir below without breaking or interfering with the film. One embodiment utilizes two rotating discs and associated terminators, with the discs rotating so as to form films in opposite directions, and with the second disc being located down beam-line relative to the first disc.

  2. Spreading of Droplets on Viscous Polymer Liquids

    NASA Astrophysics Data System (ADS)

    Pierce, Flint; Perahia, Dvora; Grest, Gary

    2009-03-01

    Significant strides have been made in understanding the spreading of liquid droplets on solid surfaces. However from biological complexes to polymeric interfaces, the surfaces are not ideal; explicitly, the surfaces may dynamically respond as spreading takes place and the droplets may partially penetrate. Molecular dynamic simulations were carried out to investigate the spreading of liquid droplets of short chains on films of viscous polymer melts. Unlike the spreading on solid surfaces, the droplets simultaneously spread and penetrate. The degree of penetration and the magnitude of damping from the film depend on the viscosity of the underlying liquid and the relative interaction of the two constituents. At the interface with viscous films a precursor foot spreads ahead of the droplet whereas on top of less viscous interfaces, the droplets penetrate while spreading with no precursor foot. A kinetic model described the spreading of shorter chain length droplets, while a hydrodynamic model better expresses the spreading of longer chain length liquid. Supported in part under DOE contract No. ER46456.

  3. Polymorphism in glassy silicon: Inherited from liquid-liquid phase transition in supercooled liquid

    NASA Astrophysics Data System (ADS)

    Zhang, Shiliang; Wang, Li-Min; Zhang, Xinyu; Qi, Li; Zhang, Suhong; Ma, Mingzhen; Liu, Riping

    2015-02-01

    Combining molecular dynamics (MD) simulation and Voronoi polyhedral analyses, we discussed the microstructure evolution in liquid and glassy silicon during cooling by focusing on the fraction of various clusters. Liquid-liquid phase transition (LLPT) is detected in supercooled liquid silicon However, freezing the high-density liquid (HDL) to the glassy state is not achieved as the quenching rate goes up to 1014 K/s. The polyamorphism in glassy silicon is found to be mainly associated with low-density liquid (LDL).

  4. Ionic liquids in chemical engineering.

    PubMed

    Werner, Sebastian; Haumann, Marco; Wasserscheid, Peter

    2010-01-01

    The development of engineering applications with ionic liquids stretches back to the mid-1990s when the first examples of continuous catalytic processes using ionic liquids and the first studies of ionic liquid-based extractions were published. Ever since, the use of ionic liquids has seen tremendous progress in many fields of chemistry and engineering, and the first commercial applications have been reported. The main driver for ionic liquid engineering applications is to make practical use of their unique property profiles, which are the result of a complex interplay of coulombic, hydrogen bonding and van der Waals interactions. Remarkably, many ionic liquid properties can be tuned in a wide range by structural modifications at their cation and anion. This review highlights specific examples of ionic liquid applications in catalysis and in separation technologies. Additionally, the application of ionic liquids as working fluids in process machines is introduced. PMID:22432579

  5. Black Liquid Solar Collector Demonstrator.

    ERIC Educational Resources Information Center

    Weichman, F. L.; Austen, D. J.

    1979-01-01

    Describes the details of constructing, and use of, a solar collector. Uses a black liquid to absorb the energy, the thermosyphon effect to drive the liquid through the collector, and a floodlamp as a surrogate sun. (GA)

  6. Predicting Polymer/Liquide Interactions

    NASA Technical Reports Server (NTRS)

    Fedors, R. F.

    1985-01-01

    Calculations of liquid absorption by rubber vulcanizates agree with experimental results. Equation allows calculation of swelling of rubber vulcanizates by liquids, based on knowledge of chemical structure of polymer and solvent. Calculated values agree favorably with experimental data.

  7. Demonstrating Paramagnetism Using Liquid Nitrogen.

    ERIC Educational Resources Information Center

    Simmonds, Ray; And Others

    1994-01-01

    Describes how liquid nitrogen is attracted to the poles of neodymium magnets. Nitrogen is not paramagnetic, so the attraction suggests that the liquid nitrogen contains a small amount of oxygen, which causes the paramagnetism. (MVL)

  8. Imaging Liquids Using Microfluidic Cells

    SciTech Connect

    Yu, Xiao-Ying; Liu, Bingwen; Yang, Li

    2013-05-10

    Chemistry occurring in the liquid and liquid surface is important in many applications. Chemical imaging of liquids using vacuum based analytical techniques is challenging due to the difficulty in working with liquids with high volatility. Recent development in microfluidics enabled and increased our capabilities to study liquid in situ using surface sensitive techniques such as electron microscopy and spectroscopy. Due to its small size, low cost, and flexibility in design, liquid cells based on microfluidics have been increasingly used in studying and imaging complex phenomena involving liquids. This paper presents a review of microfluidic cells that were developed to adapt to electron microscopes and various spectrometers for in situ chemical analysis and imaging of liquids. The following topics will be covered including cell designs, fabrication techniques, unique technical features for vacuum compatible cells, and imaging with electron microscopy and spectroscopy. Challenges are summarized and recommendations for future development priority are proposed.

  9. Liquid metal thermal electric converter

    DOEpatents

    Abbin, Joseph P. (Albuquerque, NM); Andraka, Charles E. (Albuquerque, NM); Lukens, Laurance L. (Albuquerque, NM); Moreno, James B. (Albuquerque, NM)

    1989-01-01

    A liquid metal thermal electric converter which converts heat energy to electrical energy. The design of the liquid metal thermal electric converter incorporates a unique configuration which directs the metal fluid pressure to the outside of the tube which results in the structural loads in the tube to be compressive. A liquid metal thermal electric converter refluxing boiler with series connection of tubes and a multiple cell liquid metal thermal electric converter are also provided.

  10. Liquid metal thermal electric converter

    SciTech Connect

    Abbin, J.P.; Andrake, C.E.; Lukens, L.L.; Moreno, J.B.

    1989-09-19

    This patent describes a liquid metal thermal electric converter which converts heat energy to electrical energy. The design of the liquid metal thermal electric converter incorporates a unique configuration which directs the metal fluid pressure to the outside of the tube which results in the structural loads in the tube to be compressive. A liquid metal thermal electric converter refluxing boiler with series connection of tubes and a multiple cell liquid metal thermal electric converter are also provided.

  11. Liquid crystalline composites containing phyllosilicates

    DOEpatents

    Chaiko; David J. (Naperville, IL)

    2007-05-08

    The present invention provides barrier films having reduced gas permeability for use in packaging and coating applications. The barrier films comprise an anisotropic liquid crystalline composite layer formed from phyllosilicate-polymer compositions. Phyllosilicate-polymer liquid crystalline compositions of the present invention can contain a high percentage of phyllosilicate while remaining transparent. Because of the ordering of the particles in the liquid crystalline composite, barrier films comprising liquid crystalline composites are particularly useful as barriers to gas transport.

  12. The properties of liquid carbon

    NASA Astrophysics Data System (ADS)

    Steinbeck, J.; Dresselhaus, G.; Dresselhaus, M. S.

    1990-07-01

    A model for the transport properties of liquid carbon based on Ziman liquid metal theory with refinements for polyvalent liquid metals and Fermi surface blurring is applied to calculate the electrical resistivity of liquid carbon at the melting temperature. The thermal and electrical properties predicted by the model are compared to experimental results using numerical heat flow calculations and found to be in good agreement with pulsed-current heating experiments on the resistivity of carbon fibers.

  13. Multiple liquid-liquid transitions in supercooled water

    NASA Astrophysics Data System (ADS)

    Brovchenko, Ivan; Geiger, Alfons; Oleinikova, Alla

    2003-06-01

    Three distinct liquid-liquid coexistence regions were observed for ST2 model water by restricted ensemble Monte Carlo simulations of the isotherms of homogenized systems and by phase equilibria simulations in the Gibbs ensemble. The lowest density liquid-liquid transition meets the liquid-vapor phase transition at a triple point and ends in a metastable critical point. A percolation analysis evidences, that the phase separations at the lowest and highest densities can be attributed to the separation of differently coordinated water molecules. The densities of the obtained four phases of supercooled water correlate with experimentally observed densities of amorphous ice.

  14. Liquid-Hydrogen Polygeneration System

    NASA Technical Reports Server (NTRS)

    Minderman, P.; Gutkowski, G.; Manfredi, L.; King, J.; Howard, F.

    1986-01-01

    Polygeneration system uses existing technology in integrated process to produce liquid hydrogen space-vehicle propellant and secondary products as gaseous nitrogen, electrical energy, and thermal energy. Makes commercial launch services economical. Lowers expected cost of liquid hydrogen by utilizing relatively cheap coal feedstocks and by reducing electrical costs associated with producing liquid hydrogen.

  15. High temperature liquid level sensor

    DOEpatents

    Tokarz, Richard D. (West Richland, WA)

    1983-01-01

    A length of metal sheathed metal oxide cable is perforated to permit liquid access to the insulation about a pair of conductors spaced close to one another. Changes in resistance across the conductors will be a function of liquid level, since the wetted insulation will have greater electrical conductivity than that of the dry insulation above the liquid elevation.

  16. Liquid lubrication for space applications

    NASA Technical Reports Server (NTRS)

    Fusaro, Robert L.; Khonsari, Michael M.

    1992-01-01

    Reviewed here is the state of the art of liquid lubrication for space applications. The areas discussed are types of liquid lubrication mechanisms, space environmental effects on lubrication, classification of lubricants, liquid lubricant additives, grease lubrication, mechanism materials, bearing anomalies and failures, lubricant supply techniques, and application types and lubricant needs for those applications.

  17. Liquid/Gas Flow Mixers

    NASA Technical Reports Server (NTRS)

    Fabris, Gracio

    1994-01-01

    Improved devices mix gases and liquids into bubbly or foamy flows. Generates flowing, homogeneous foams or homogeneous dispersions of small, noncoalescing bubbles entrained in flowing liquids. Mixers useful in liquid-metal magnetohydrodynamic electric-power generator, froth flotation in mining industry, wastewater treatment, aerobic digestion, and stripping hydrocarbon contaminants from ground water.

  18. Acceleration in liquids and gas'

    NASA Astrophysics Data System (ADS)

    Schrer, H.

    We dip a cuboid and a ball in a liquid. We search the force on the body. We look at an arbitrary body in a liquid. Is this result valid for all bodies in a liquid? This question can be answered with "yes". Then we view two masses under a shade. There is an english and a german edition.

  19. Percolating networks and liquid liquid transitions in supercooled water

    NASA Astrophysics Data System (ADS)

    Oleinikova, Alla; Brovchenko, Ivan

    2006-09-01

    The anomalous behaviour of various properties of liquid water upon cooling may be explained by approaching the percolation transition of the four-coordinated water molecules or by approaching the liquid-liquid transition. We have found these two explanations are intrinsically closely related by locating the line of the percolation transitions of the four-coordinated water molecules with respect to the liquid-vapour and liquid-liquid transitions of ST2 water. The saturated liquid water upon cooling crosses the percolation threshold of the four-coordinated water molecules, which is close to the binodal (spinodal) of the first (lowest-density) liquid-liquid transition of water. This finding agrees with the known close relation between the phase transition and the percolation transition of physical clusters. The lowest-density amorphous water phase is characterized by presence of a percolating network of the four-coordinated water molecules. The line of the percolation transitions of tetrahedrally ordered water molecules (with arbitrary coordination number) envelops the whole region where liquid-liquid transitions occur. So, the percolating network of the tetrahedrally ordered water molecules is absent in the highest-density amorphous water phase.

  20. Liquid Acquisition Device Testing with Sub-Cooled Liquid Oxygen

    NASA Technical Reports Server (NTRS)

    Jurns, John M.; McQuillen, John B.

    2008-01-01

    When transferring propellant in space, it is most efficient to transfer single phase liquid from a propellant tank to an engine. In earth s gravity field or under acceleration, propellant transfer is fairly simple. However, in low gravity, withdrawing single-phase fluid becomes a challenge. A variety of propellant management devices (PMD) are used to ensure single-phase flow. One type of PMD, a liquid acquisition device (LAD) takes advantage of capillary flow and surface tension to acquire liquid. Previous experimental test programs conducted at NASA have collected LAD data for a number of cryogenic fluids, including: liquid nitrogen (LN2), liquid oxygen (LOX), liquid hydrogen (LH2), and liquid methane (LCH4). The present work reports on additional testing with sub-cooled LOX as part of NASA s continuing cryogenic LAD development program. Test results extend the range of LOX fluid conditions examined, and provide insight into factors affecting predicting LAD bubble point pressures.

  1. The dynamics of free liquid drops

    NASA Technical Reports Server (NTRS)

    Wang, T. G.; Trinh, E. H.; Croonquist, A. P.; Elleman, D. D.

    1988-01-01

    The behavior of rotating and oscillating free liquid drops was studied by many investigators theoretically for many years. More recent numerical treatments have yielded predictions which are yet to be verified experimentally. The purpose is to report the results of laboratory work as well as that of the experiments carried out in space during the flight of Spacelab 3, and to compare it with the existing theoretical studies. Ground-based experiments were attempted as a first approximation to the ideal boundary conditions used by the theoretical treatments by neutralizing the overwhelming effects of the Earth's gravitational field with an outside supporting liquid and with the use of levitation technology. The viscous and inertial loading of such a suspending fluid was found to profoundly effect the results, but the information thus gathered has emphasized the uniqueness of the experimental data obtained in the low-gravity environment of space.

  2. Electrowetting of ionic liquids.

    PubMed

    Millefiorini, Stefano; Tkaczyk, Alan H; Sedev, Rossen; Efthimiadis, Jim; Ralston, John

    2006-03-01

    We have successfully demonstrated that imidazolium- and pyrrolidinium-based commercial room-temperature ionic liquids can electrowet (with a dc voltage) a smooth fluoropolymer (Teflon AF1600) surface. Qualitatively, the process is analogous to the electrowetting of aqueous electrolyte solutions: the contact angle versus voltage curve has a parabolic shape which saturates at larger voltages (positive or negative). On the other hand we observed several peculiarities: (i) the efficiency is significantly lower (by about an order of magnitude); (ii) the influence of the bulky cation is larger and the importance of the smaller anion is lesser, especially with respect to electrowetting saturation; (iii) there is an asymmetry in the saturation contact angles found for positive and negative voltages. The asymmetry may be correlated with the cation-anion asymmetry of the ionic liquids. The low efficiency may be caused by the presence of water and other impurities in these commercial materials. PMID:16506791

  3. Liquid evaporation light deflector.

    PubMed

    Taylor, G W

    1972-03-01

    A new type of general purpose digital light deflector is described, which is based on the electrically controlled vaporization of a high refractive index transparent liquid at an inclined interface formed by the liquid and a transparent solid. Deflectors operating on this principle can be designed to provide multiposition linear or angular displacement of a light beam in one or two dimensions. Such deflectors can be random accessed, are capable of large angular deflection, are simple and cheap to build, occupy a small volume, and should have a long operating life. Furthermore, they are not limited to deflecting only small diameter, monochromatic, polarized light beams. Millisecond deflection is possible at power levels of 0.3 W/mm(2) of light beam area. The deflectors have high optical transmission efficiency with on-off contrast ratios of 150: 1 and higher. PMID:20111551

  4. Liquid metal magnetohydrodynamics

    SciTech Connect

    Lielpeteris, J. ); ))

    1989-01-01

    Liquid metal MHD is the subject of this book. It is of central importance in fields like metals processing, energy conversion, nuclear engineering (fast breeders or fusion reactors), geomagnetism and astrophysics. In some circumstances fluid flow phenomena are controlled by an existing magnetic field; the melts in induction furnaces or the liquid metal blanket around future tokamak fusion reactors being significant examples. In other cases the application of an external magnetic field (or of an electric current) may generate drastic modifications in the fluid motion and in the transfer rates; such effects may be used to develop new technologies (electromagnetic shaping) or to improve existing techniques (electromagnetic stirring in continuous casting). In the core of the Earth, fluid motion and magnetic fields are both present and their interaction governs important phenomena.

  5. Liquid filmification from menisci

    NASA Astrophysics Data System (ADS)

    Spruijt, Evan; Le Guludec, Erwan; Lix, Clément; Wagner, Marc; Quéré, David

    2015-10-01

    A wetting liquid brought in contact with a solid covered by microtextures invades the network of textures and fills it, creating a liquid film whose thickness is fixed by the texture height. However, this process of filmification can be opposed by the presence of surrounding menisci, residing for instance in corners at the edges of the film. We discuss the nature to be given to the texture to overcome the negative Laplace pressure associated with menisci. We also describe how the dynamics of filmification is impacted by the design of the texture, focussing on micropillars, lines and grooves, and how it can be optimized for some texture density. We conclude by discussing the distribution of textures generating a constant velocity of filmification instead of the slowing-down classically observed in impregnation processes.

  6. Weyl spin liquids.

    PubMed

    Hermanns, M; O'Brien, K; Trebst, S

    2015-04-17

    The fractionalization of quantum numbers in interacting quantum many-body systems is a central motif in condensed-matter physics with prominent examples including the fractionalization of the electron in quantum Hall liquids or the emergence of magnetic monopoles in spin-ice materials. Here, we discuss the fractionalization of magnetic moments in three-dimensional Kitaev models into Majorana fermions (and a Z_{2} gauge field) and their emergent collective behavior. We analytically demonstrate that the Majorana fermions form a Weyl superconductor for the Kitaev model on the recently synthesized hyperhoneycomb structure of β-Li_{2}IrO_{3} when applying a magnetic field. We characterize the topologically protected bulk and surface features of this state, which we dub a Weyl spin liquid, including thermodynamic and transport signatures. PMID:25933336

  7. On the identification of liquid surface properties using liquid bridges.

    PubMed

    Kostoglou, M; Karapantsios, T D

    2015-08-01

    The term liquid bridge refers to the specific silhouette of a liquid volume when it is placed between two solid surfaces. Liquid bridges have been studied extensively both theoretically and experimentally during the last century due to their significance in many technological applications. It is worth noticing that even today new technological applications based on liquid bridges continue to appear. A liquid bridge has a well-defined surface configuration dictated by a rigid theoretical foundation so the potential of its utilization as a tool to study surface properties of liquids is apparent. However, it is very scarce in literature that the use of liquid bridges is suggested as an alternative to the well-established drop techniques (pendant/sessile drop). The present work (i) presents the theoretical background for setting up a liquid-bridge based surface property estimation problem, (ii) describes the required experimental equipment and procedures and (iii) performs a thorough literature review on the subject. A case with particular interest is that of liquid bridges made of electrically conducting liquids forming between two conducting solids; such a liquid bridge presents an integral electrical conductance value which is sensitive to the specific silhouette of the bridge. This enables the use of this integral conductance as shape descriptor instead of the conventional image processing techniques. Several attempts in literature for the estimation of liquid surface tension, liquid-solid contact angle and surfactant induced surface elasticity for conducting or non/conducting liquids are presented and the prospects of the technique are discussed. PMID:24819725

  8. Liquids with permanent porosity

    NASA Astrophysics Data System (ADS)

    Giri, Nicola; Del Pópolo, Mario G.; Melaugh, Gavin; Greenaway, Rebecca L.; Rätzke, Klaus; Koschine, Tönjes; Pison, Laure; Gomes, Margarida F. Costa; Cooper, Andrew I.; James, Stuart L.

    2015-11-01

    Porous solids such as zeolites and metal–organic frameworks are useful in molecular separation and in catalysis, but their solid nature can impose limitations. For example, liquid solvents, rather than porous solids, are the most mature technology for post-combustion capture of carbon dioxide because liquid circulation systems are more easily retrofitted to existing plants. Solid porous adsorbents offer major benefits, such as lower energy penalties in adsorption–desorption cycles, but they are difficult to implement in conventional flow processes. Materials that combine the properties of fluidity and permanent porosity could therefore offer technological advantages, but permanent porosity is not associated with conventional liquids. Here we report free-flowing liquids whose bulk properties are determined by their permanent porosity. To achieve this, we designed cage molecules that provide a well-defined pore space and that are highly soluble in solvents whose molecules are too large to enter the pores. The concentration of unoccupied cages can thus be around 500 times greater than in other molecular solutions that contain cavities, resulting in a marked change in bulk properties, such as an eightfold increase in the solubility of methane gas. Our results provide the basis for development of a new class of functional porous materials for chemical processes, and we present a one-step, multigram scale-up route for highly soluble ‘scrambled’ porous cages prepared from a mixture of commercially available reagents. The unifying design principle for these materials is the avoidance of functional groups that can penetrate into the molecular cage cavities.

  9. RHIC The Perfect Liquid

    ScienceCinema

    BNL

    2009-09-01

    Evidence to date suggests that gold-gold collisions the Relativistic Heavy Ion Collider at Brookhaven are indeed creating a new state of hot, dense matter, but one quite different and even more remarkable than had been predicted. Instead of behaving like a gas of free quarks and gluons, as was expected, the matter created in RHIC's heavy ion collisions appears to be more like a "perfect" liquid.

  10. Liquid fuel cells.

    PubMed

    Soloveichik, Grigorii L

    2014-01-01

    The advantages of liquid fuel cells (LFCs) over conventional hydrogen-oxygen fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. This review focuses on the use of different types of organic fuels as an anode material for LFCs. An overview of the current state of the art and recent trends in the development of LFC and the challenges of their practical implementation are presented. PMID:25247123

  11. Liquids with permanent porosity.

    PubMed

    Giri, Nicola; Del Ppolo, Mario G; Melaugh, Gavin; Greenaway, Rebecca L; Rtzke, Klaus; Koschine, Tnjes; Pison, Laure; Gomes, Margarida F Costa; Cooper, Andrew I; James, Stuart L

    2015-11-12

    Porous solids such as zeolites and metal-organic frameworks are useful in molecular separation and in catalysis, but their solid nature can impose limitations. For example, liquid solvents, rather than porous solids, are the most mature technology for post-combustion capture of carbon dioxide because liquid circulation systems are more easily retrofitted to existing plants. Solid porous adsorbents offer major benefits, such as lower energy penalties in adsorption-desorption cycles, but they are difficult to implement in conventional flow processes. Materials that combine the properties of fluidity and permanent porosity could therefore offer technological advantages, but permanent porosity is not associated with conventional liquids. Here we report free-flowing liquids whose bulk properties are determined by their permanent porosity. To achieve this, we designed cage molecules that provide a well-defined pore space and that are highly soluble in solvents whose molecules are too large to enter the pores. The concentration of unoccupied cages can thus be around 500 times greater than in other molecular solutions that contain cavities, resulting in a marked change in bulk properties, such as an eightfold increase in the solubility of methane gas. Our results provide the basis for development of a new class of functional porous materials for chemical processes, and we present a one-step, multigram scale-up route for highly soluble 'scrambled' porous cages prepared from a mixture of commercially available reagents. The unifying design principle for these materials is the avoidance of functional groups that can penetrate into the molecular cage cavities. PMID:26560299

  12. Liquid fuel cells

    PubMed Central

    2014-01-01

    Summary The advantages of liquid fuel cells (LFCs) over conventional hydrogen–oxygen fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. This review focuses on the use of different types of organic fuels as an anode material for LFCs. An overview of the current state of the art and recent trends in the development of LFC and the challenges of their practical implementation are presented. PMID:25247123

  13. Liquid bridges with thermocapillarity

    NASA Technical Reports Server (NTRS)

    Xu, J.-J.; Davis, S. H.

    1983-01-01

    An axisymmetric liquid bridge is subjected to an axial temperature gradient. Thermal variations in surface tension drive a motion that is described using lubrication theory for slender bridges. At leading order in aspect ratio, a class of similarity solutions is obtained valid in the core region away from the endwalls of the bridge. These solutions describe the flows, temperature fields, and interfacial shapes of bridges that may sustain substantial interfacial deflections.

  14. RHIC The Perfect Liquid

    SciTech Connect

    BNL

    2008-08-12

    Evidence to date suggests that gold-gold collisions the Relativistic Heavy Ion Collider at Brookhaven are indeed creating a new state of hot, dense matter, but one quite different and even more remarkable than had been predicted. Instead of behaving like a gas of free quarks and gluons, as was expected, the matter created in RHIC's heavy ion collisions appears to be more like a "perfect" liquid.

  15. Liquid Crystals in Tribology

    PubMed Central

    Carrión, Francisco-José; Martínez-Nicolás, Ginés; Iglesias, Patricia; Sanes, José; Bermúdez, María-Dolores

    2009-01-01

    Two decades ago, the literature dealing with the possible applications of low molar mass liquid crystals, also called monomer liquid crystals (MLCs), only included about 50 references. Today, thousands of papers, conference reports, books or book chapters and patents refer to the study and applications of MLCs as lubricants and lubricant additives and efforts are made to develop new commercial applications. The development of more efficient lubricants is of paramount technological and economic relevance as it is estimated that half the energy consumption is dissipated as friction. MLCs have shown their ability to form ordered boundary layers with good load-carrying capacity and to lower the friction coefficients, wear rates and contact temperature of sliding surfaces, thus contributing to increase the components service life and to save energy. This review includes the use of MLCs in lubrication, and dispersions of MLCs in conventional polymers (PDMLCs). Finally, new lubricating system composed of MLC blends with surfactants, ionic liquids or nanophases are considered. PMID:19865534

  16. Living liquid crystals

    PubMed Central

    Zhou, Shuang; Sokolov, Andrey; Lavrentovich, Oleg D.; Aranson, Igor S.

    2014-01-01

    Collective motion of self-propelled organisms or synthetic particles, often termed “active fluid,” has attracted enormous attention in the broad scientific community because of its fundamentally nonequilibrium nature. Energy input and interactions among the moving units and the medium lead to complex dynamics. Here, we introduce a class of active matter––living liquid crystals (LLCs)––that combines living swimming bacteria with a lyotropic liquid crystal. The physical properties of LLCs can be controlled by the amount of oxygen available to bacteria, by concentration of ingredients, or by temperature. Our studies reveal a wealth of intriguing dynamic phenomena, caused by the coupling between the activity-triggered flow and long-range orientational order of the medium. Among these are (i) nonlinear trajectories of bacterial motion guided by nonuniform director, (ii) local melting of the liquid crystal caused by the bacteria-produced shear flows, (iii) activity-triggered transition from a nonflowing uniform state into a flowing one-dimensional periodic pattern and its evolution into a turbulent array of topological defects, and (iv) birefringence-enabled visualization of microflow generated by the nanometers-thick bacterial flagella. Unlike their isotropic counterpart, the LLCs show collective dynamic effects at very low volume fraction of bacteria, on the order of 0.2%. Our work suggests an unorthodox design concept to control and manipulate the dynamic behavior of soft active matter and opens the door for potential biosensing and biomedical applications. PMID:24474746

  17. Advanced Liquid Feed Experiment

    NASA Astrophysics Data System (ADS)

    Distefano, E.; Noll, C.

    1993-06-01

    The Advanced Liquid Feed Experiment (ALFE) is a Hitchhiker experiment flown on board the Shuttle of STS-39 as part of the Space Test Payload-1 (STP-1). The purpose of ALFE is to evaluate new propellant management components and operations under the low gravity flight environment of the Space Shuttle for eventual use in an advanced spacecraft feed system. These components and operations include an electronic pressure regulator, an ultrasonic flowmeter, an ultrasonic point sensor gage, and on-orbit refill of an auxiliary propellant tank. The tests are performed with two transparent tanks with dyed Freon 113, observed by a camera and controlled by ground commands and an on-board computer. Results show that the electronic pressure regulator provides smooth pressure ramp-up, sustained pressure control, and the flexibility to change pressure settings in flight. The ultrasonic flowmeter accurately measures flow and detects gas ingestion. The ultrasonic point sensors function well in space, but not as a gage during sustained low-gravity conditions, as they, like other point gages, are subject to the uncertainties of propellant geometry in a given tank. Propellant transfer operations can be performed with liquid-free ullage equalization at a 20 percent fill level, gas-free liquid transfer from 20-65 percent fill level, minimal slosh, and can be automated.

  18. Liquid crystals in tribology.

    PubMed

    Carrión, Francisco-José; Martínez-Nicolás, Ginés; Iglesias, Patricia; Sanes, José; Bermúdez, María-Dolores

    2009-09-01

    Two decades ago, the literature dealing with the possible applications of low molar mass liquid crystals, also called monomer liquid crystals (MLCs), only included about 50 references. Today, thousands of papers, conference reports, books or book chapters and patents refer to the study and applications of MLCs as lubricants and lubricant additives and efforts are made to develop new commercial applications. The development of more efficient lubricants is of paramount technological and economic relevance as it is estimated that half the energy consumption is dissipated as friction. MLCs have shown their ability to form ordered boundary layers with good load-carrying capacity and to lower the friction coefficients, wear rates and contact temperature of sliding surfaces, thus contributing to increase the components service life and to save energy. This review includes the use of MLCs in lubrication, and dispersions of MLCs in conventional polymers (PDMLCs). Finally, new lubricating system composed of MLC blends with surfactants, ionic liquids or nanophases are considered. PMID:19865534

  19. Liquid Hydrogen: Target, Detector

    SciTech Connect

    Mulholland, G.T.; Harigel, G.G.

    2004-06-23

    In 1952 D. Glaser demonstrated that a radioactive source's radiation could boil 135 deg. C superheated-diethyl ether in a 3-mm O glass vessel and recorded bubble track growth on high-speed film in a 2-cm3 chamber. This Bubble Chamber (BC) promised improved particle track time and spatial resolution and cycling rate. Hildebrand and Nagle, U of Chicago, reported Liquid Hydrogen minimum ionizing particle boiling in August 1953. John Wood created the 3.7-cm O Liquid Hydrogen BC at LBL in January 1954. By 1959 the Lawrence Berkley Laboratory (LBL) Alvarez group's '72-inch' BC had tracks in liquid hydrogen. Within 10 years bubble chamber volumes increased by a factor of a million and spread to every laboratory with a substantial high-energy physics program. The BC, particle accelerators and special separated particle beams created a new era of High Energy Physics (HEP) experimentation. The BC became the largest most complex cryogenic installation at the world's HEP laboratories for decades. The invention and worldwide development, deployment and characteristics of these cryogenic dynamic target/detectors and related hydrogen targets are described.

  20. Dynamics in Nanoparticle Liquids

    NASA Astrophysics Data System (ADS)

    Mirau, Peter; Jespersen, Michael; Vaia, Richard; Rodriguez, Robert; Giannelis, Emmanuel

    2009-03-01

    Nanoscale Ionic Materials (NIMS) are organic-inorganic hybrids in which a nanometer-sized core is functionalized with a covalently attached corona and an ionically tethered canopy. NIMS can be engineered to be liquids at ambient temperature in the absence of solvent and are of interest for a variety of applications. We have used NMR relaxation and pulse-field gradient NMR to measure the dynamics of NIMS made from a 20 nm silica core modified with propyl sulfonic acid groups and amino-terminated ethylene oxide/propylene oxide block copolymers. Carbon NMR studies show that the block copolymer canopy is quite mobile both in the bulk and the nanoparticle liquid. The carbon spin-lattice relaxation times as a function of temperature are fit to a model with rapid librational motions and slower reorientation of the copolymer. Neither the correlation times for reorientation of the block copolymer nor the self-diffusion coefficient are influenced by the presence of the silica nanoparticle core. These data suggest that the liquid-like behavior in NIMS is due to rapid exchange of the block copolymer canopy between the ionically modified nanoparticles.