WorldWideScience

Sample records for glass capillary column

  1. Thermally stable dexsil-400 glass capillary columns

    International Nuclear Information System (INIS)

    Maskarinec, M.P.; Olerich, G.

    1980-01-01

    The factors affecting efficiency, thermal stability, and reproducibility of Dexsil-400 glass capillary columns for gas chromatography in general, and for polycyclic aromatic hydrocarbons (PAHs) in particular were investigated. Columns were drawn from Kimble KG-6 (soda-lime) glass or Kimox (borosilicate) glass. All silylation was carried out at 200 0 C. Columns were coated according to the static method. Freshly prepared, degassed solutions of Dexsil-400 in pentane or methylene chloride were used. Thermal stability of the Dexsil 400 columns with respect to gas chromatography/mass spectrometry (GC/MS) were tested. Column-to-column variability is a function of each step in the fabrication of the columns. The degree of etching, extent of silylation, and stationary phase film thickness must be carefully controlled. The variability in two Dexsil-400 capillary column prepared by etching, silylation with solution of hexa methyl disilazone (HMDS), and static coating is shown and also indicates the excellent selectivity of Dexsil-400 for the separation of alkylated aromatic compounds. The wide temperature range of Dexsil-400 and the high efficiency of the capillary columns also allow the analysis of complex mixtures with minimal prefractionation. Direct injection of a coal liquefaction product is given. Analysis by GC/MS indicated the presence of parent PAHs, alkylated PAHs, nitrogen and sulfur heterocycles, and their alkylated derivatives. 4 figures

  2. Analysis of polycyclic aromatic hydrocarbons I. Determination by gas chromatography with glass and fused silica capillary columns

    International Nuclear Information System (INIS)

    Perez, M. M.; Gonzalez, D.

    1987-01-01

    A study of the analysis by gas chromatography of aromatic polycyclic hydrocarbons is presented. The separation has been carried out by glass and fused silica capillary column. The limitations and the advantages of the procedure are discussed in terms of separation efficiency, sensitivity and precision. (Author) 17 refs

  3. Analysis of polycyclic aromatic hydrocarbons. I. Determination by gas chromatography with glass and fused solica capillary columns

    International Nuclear Information System (INIS)

    Perez Garcia, M.; Gonzalez, D.

    1987-01-01

    A study of the analysis by gas chromatography of aromatic polycyclic hydrocarbons is presented. The separation has been carried out by glass and fused silice capillary column. The limitations and the advantages of the procedure are discussed in terms of separation efficiency, sensitivity and precision. (author). 3 figs., 17 refs

  4. Assembly for connecting the column ends of two capillary columns

    International Nuclear Information System (INIS)

    Kolb, B.; Auer, M.; Pospisil, P.

    1984-01-01

    In gas chromatography, the column ends of two capillary columns are inserted into a straight capillary from both sides forming annular gaps. The capillary is located in a tee out of which the capillary columns are sealingly guided, and to which carrier gas is supplied by means of a flushing flow conduit. A ''straight-forward operation'' having capillary columns connected in series and a ''flush-back operation'' are possible. The dead volume between the capillary columns can be kept small

  5. Analysis of polycyclic aromatic hydrocarbons I. Determination by gas chromatography with glass and fused silica capillary columns; Analisis de Hidrocarburos aromaticos policiclicos. I. Determinacion por cromatografia de gases con columnas capilares de vidrio de silice fundida

    Energy Technology Data Exchange (ETDEWEB)

    Perez, M M; Gonzalez, D

    1987-07-01

    A study of the analysis by gas chromatography of aromatic polycyclic hydrocarbons is presented. The separation has been carried out by glass and fused silica capillary column. The limitations and the advantages of the procedure are discussed in terms of separation efficiency, sensitivity and precision. (Author) 17 refs.

  6. Microfluidic PMMA interfaces for rectangular glass capillaries

    International Nuclear Information System (INIS)

    Evander, Mikael; Tenje, Maria

    2014-01-01

    We present the design and fabrication of a polymeric capillary fluidic interface fabricated by micro-milling. The design enables the use of glass capillaries with any kind of cross-section in complex microfluidic setups. We demonstrate two different designs of the interface; a double-inlet interface for hydrodynamic focusing and a capillary interface with integrated pneumatic valves. Both capillary interfaces are presented together with examples of practical applications. This communication shows the design optimization and presents details of the fabrication process. The capillary interface opens up for the use of complex microfluidic systems in single-use glass capillaries. They also enable simple fabrication of glass/polymer hybrid devices that can be beneficial in many research fields where a pure polymer chip negatively affects the device's performance, e.g. acoustofluidics. (technical note)

  7. Comparison of monolithic silica and polymethacrylate capillary columns for LC

    Czech Academy of Sciences Publication Activity Database

    Moravcová, D.; Jandera, P.; Urban, J.; Planeta, Josef

    2004-01-01

    Roč. 27, 10-11 (2004), s. 789-800 ISSN 1615-9306 R&D Projects: GA ČR(CZ) GA203/02/0023 Keywords : monolithic column s * capillary HPLC * column testing Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.927, year: 2004

  8. An all-glass solid sampling device for open tubular columns in gas chromatography

    NARCIS (Netherlands)

    Cox, T.P.H.; vd Berg, P.M.J.

    1972-01-01

    An all-glass system for direct sample-introduction of high-boiling compounds onto open tubular columns is described. The standard deviation for quantitative measurements is less than 2.7%. The loss in resolving power of capillary columns, due to this injection system is negligible. The system is

  9. Open tubular capillary column for the separation of cytochrome C tryptic digest in capillary electrochromatography.

    Science.gov (United States)

    Ali, Faiz; Cheong, Won Jo

    2015-10-01

    A silica capillary of 50 μm internal diameter and 500 mm length (416 mm effective length) was chemically modified with 4-(trifluoromethoxy) phenyl isocyanate in the presence of dibutyl tin dichloride as catalyst. Sodium diethyl dithiocarbamate was reacted with the terminal halogen of the bound ligand to incorporate the initiator moiety, and in situ polymerization was performed using a monomer mixture of styrene, N-phenylacrylamide, and methacrylic acid. The resultant open tubular capillary column immobilized with the copolymer layer was used for the separation of tryptic digest of cytochrome C in capillary electrochromatography. The sample was well eluted and separated into many components. The elution patterns of tryptic digest of cytochrome C were studied with respect to pH and water content in the mobile phase. This preliminary study demonstrates that open tubular capillary electrochromatography columns with a modified copolymer layer composed of proper nonpolar and polar units fabricated by reversible addition-fragmentation transfer polymerization can be useful as separation media for proteomic analysis. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Dopamine-imprinted monolithic column for capillary electrochromatography.

    Science.gov (United States)

    Aşır, Süleyman; Sarı, Duygu; Derazshamshir, Ali; Yılmaz, Fatma; Şarkaya, Koray; Denizli, Adil

    2017-11-01

    A dopamine-imprinted monolithic column was prepared and used in capillary electrochromatography as stationary phase for the first time. Dopamine was selectively separated from aqueous solution containing the competitor molecule norepinephrine, which is similar in size and shape to the template molecule. Morphology of the dopamine-imprinted column was observed by scanning electron microscopy. The influence of the organic solvent content of mobile phase, applied pressure and pH of the mobile phase on the recognition of dopamine by the imprinted monolithic column has been evaluated, and the imprinting effect in the dopamine-imprinted monolithic polymer was verified. Developed dopamine-imprinted monolithic column resulted in excellent separation of dopamine from structurally related competitor molecule, norepinephrine. Separation was achieved in a short period of 10 min, with the electrophoretic mobility of 5.81 × 10 -5  m 2 V -1 s -1 at pH 5.0 and 500 mbar pressure. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Experimental Verification of the Structural Glass Beam-Columns Strength

    Science.gov (United States)

    Pešek, Ondřej; Melcher, Jindřich; Balázs, Ivan

    2017-10-01

    This paper deals with experimental research of axially and laterally loaded members made of structural (laminated) glass. The purpose of the research is the evaluation of buckling strength and actual behaviour of the beam-columns due to absence of standards for design of glass load-bearing structures. The experimental research follows the previous one focusing on measuring of initial geometrical imperfections of glass members, testing of glass beams and columns. Within the frame of the research 9 specimens were tested. All of them were of the same geometry (length 2000 mm, width 200 mm and thickness 16 mm) but different composition - laminated double glass made of annealed glass or fully tempered glass panes bonded together by PVB or EVASAFE foil. Specimens were at first loaded by axial force and then by constantly increasing bending moment up to failure. During testing lateral deflections, vertical deflection and normal stresses at mid-span were measured. A maximum load achieved during testing has been adopted as flexural-lateral-torsional buckling strength. The results of experiments were statistically evaluated according to the European standard for design of structures EN 1990, appendix D. There are significant differences between specimens made of annealed glass or fully tempered glass. Differences between specimens loaded by axial forces 1 kN and 2 kN are negligible. The next step was to determine the design strength by calculation procedure based on buckling curves approach intended for design of steel columns and develop interaction criterion for glass beams-columns.

  12. Recent advances in the preparation and application of monolithic capillary columns in separation science

    International Nuclear Information System (INIS)

    Hong, Tingting; Yang, Xi; Xu, Yujing; Ji, Yibing

    2016-01-01

    Novel column technologies involving various materials and efficient reactions have been investigated for the fabrication of monolithic capillary columns in the field of analytical chemistry. In addition to the development of these miniaturized systems, a variety of microscale separation applications have achieved noteworthy results, providing a stepping stone for new types of chromatographic columns with improved efficiency and selectivity. Three novel strategies for the preparation of capillary monoliths, including ionic liquid-based approaches, nanoparticle-based approaches and “click chemistry”, are highlighted in this review. Furthermore, we present the employment of state-of-the-art capillary monolithic stationary phases for enantioseparation, solid-phase microextraction, mixed-mode separation and immobilized enzyme reactors. The review concludes with recommendations for future studies and improvements in this field of research. - Highlights: • Preparation of novel monolithic capillary columns have shown powerful potential in analytical chemistry field. • Various materials including ionic liquids and nanoparticles involved into capillary monolithic micro-devices are concluded. • Click chemistry strategy applied for preparing monolithic capillary columns is reviewed. • Recent strategies utilized in constructing different capillary monoliths for enantiomeric separation are summarized. • Advancement of capillary monoliths for complex samples analysis is comprehensively described.

  13. Recent advances in the preparation and application of monolithic capillary columns in separation science

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Tingting; Yang, Xi; Xu, Yujing [Department of Analytical Chemistry, China Pharmaceutical University, Nanjing, 210009 (China); Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, Nanjing, 210009 (China); Ji, Yibing, E-mail: jiyibing@msn.com [Department of Analytical Chemistry, China Pharmaceutical University, Nanjing, 210009 (China); Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, Nanjing, 210009 (China)

    2016-08-10

    Novel column technologies involving various materials and efficient reactions have been investigated for the fabrication of monolithic capillary columns in the field of analytical chemistry. In addition to the development of these miniaturized systems, a variety of microscale separation applications have achieved noteworthy results, providing a stepping stone for new types of chromatographic columns with improved efficiency and selectivity. Three novel strategies for the preparation of capillary monoliths, including ionic liquid-based approaches, nanoparticle-based approaches and “click chemistry”, are highlighted in this review. Furthermore, we present the employment of state-of-the-art capillary monolithic stationary phases for enantioseparation, solid-phase microextraction, mixed-mode separation and immobilized enzyme reactors. The review concludes with recommendations for future studies and improvements in this field of research. - Highlights: • Preparation of novel monolithic capillary columns have shown powerful potential in analytical chemistry field. • Various materials including ionic liquids and nanoparticles involved into capillary monolithic micro-devices are concluded. • Click chemistry strategy applied for preparing monolithic capillary columns is reviewed. • Recent strategies utilized in constructing different capillary monoliths for enantiomeric separation are summarized. • Advancement of capillary monoliths for complex samples analysis is comprehensively described.

  14. New Liquid Phases for the Gas Chromatographic Separation of Strong Bases on Capillary Columns

    OpenAIRE

    Grob, K.

    2017-01-01

    The current practice of pretreating the solid support with free alkali to increase separation efficiency for basic compounds proved to be unsuitable for capillary columns. Instead of this, homogenous organic materials of high base strength are required. We found polyethylene imine (PEI) and polypropylene imine (PPI) to be very efficient as liquid phases of capillary columns for the separation of bases. The preparation of polymers is mentioned. Silanization or acetylation of the free hydroxyl ...

  15. Wall modified photonic crystal fibre capillaries as porous layer open tubular columns for in-capillary micro-extraction and capillary chromatography

    International Nuclear Information System (INIS)

    Kazarian, Artaches A.; Sanz Rodriguez, Estrella; Deverell, Jeremy A.; McCord, James; Muddiman, David C.; Paull, Brett

    2016-01-01

    Wall modified photonic crystal fibre capillary columns for in-capillary micro-extraction and liquid chromatographic separations is presented. Columns contained 126 internal parallel 4 μm channels, each containing a wall bonded porous monolithic type polystyrene-divinylbenzene layer in open tubular column format (PLOT). Modification longitudinal homogeneity was monitored using scanning contactless conductivity detection and scanning electron microscopy. The multichannel open tubular capillary column showed channel diameter and polymer layer consistency of 4.2 ± 0.1 μm and 0.26 ± 0.02 μm respectively, and modification of 100% of the parallel channels with the monolithic polymer. The modified multi-channel capillaries were applied to the in-capillary micro-extraction of water samples. 500 μL of water samples containing single μg L"−"1 levels of polyaromatic hydrocarbons were extracted at a flow rate of 10 μL min"−"1, and eluted in 50 μL of acetonitrile for analysis using HPLC with fluorescence detection. HPLC LODs were 0.08, 0.02 and 0.05 μg L"−"1 for acenaphthene, anthracene and pyrene, respectively, with extraction recoveries of between 77 and 103%. The modified capillaries were also investigated briefly for direct application to liquid chromatographic separations, with the retention and elution of a standard protein (cytochrome c) under isocratic conditions demonstrated, proving chromatographic potential of the new column format, with run-to-run retention time reproducibility of below 1%. - Highlights: • Novel PS-DVB modified photonic crystal fibres for in-capillary micro-extraction. • New method for micro-extraction of PAHs and HPLC-FL detection at sub-ppb levels. • Demonstration of PS-DVB modified photonic crystal fibres for capillary bioseparations.

  16. Wall modified photonic crystal fibre capillaries as porous layer open tubular columns for in-capillary micro-extraction and capillary chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Kazarian, Artaches A. [Australian Centre for Research on Separation Science, School of Physical Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001 (Australia); W.M. Keck FT-ICR-MS Laboratory, Department of Chemistry, North Carolina State University, Raleigh, NC (United States); Sanz Rodriguez, Estrella; Deverell, Jeremy A. [Australian Centre for Research on Separation Science, School of Physical Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001 (Australia); McCord, James; Muddiman, David C. [W.M. Keck FT-ICR-MS Laboratory, Department of Chemistry, North Carolina State University, Raleigh, NC (United States); Paull, Brett, E-mail: Brett.Paull@utas.edu.au [Australian Centre for Research on Separation Science, School of Physical Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001 (Australia); ARC Centre of Excellence for Electromaterials Science, School of Physical Sciences, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001 (Australia)

    2016-01-28

    Wall modified photonic crystal fibre capillary columns for in-capillary micro-extraction and liquid chromatographic separations is presented. Columns contained 126 internal parallel 4 μm channels, each containing a wall bonded porous monolithic type polystyrene-divinylbenzene layer in open tubular column format (PLOT). Modification longitudinal homogeneity was monitored using scanning contactless conductivity detection and scanning electron microscopy. The multichannel open tubular capillary column showed channel diameter and polymer layer consistency of 4.2 ± 0.1 μm and 0.26 ± 0.02 μm respectively, and modification of 100% of the parallel channels with the monolithic polymer. The modified multi-channel capillaries were applied to the in-capillary micro-extraction of water samples. 500 μL of water samples containing single μg L{sup −1} levels of polyaromatic hydrocarbons were extracted at a flow rate of 10 μL min{sup −1}, and eluted in 50 μL of acetonitrile for analysis using HPLC with fluorescence detection. HPLC LODs were 0.08, 0.02 and 0.05 μg L{sup −1} for acenaphthene, anthracene and pyrene, respectively, with extraction recoveries of between 77 and 103%. The modified capillaries were also investigated briefly for direct application to liquid chromatographic separations, with the retention and elution of a standard protein (cytochrome c) under isocratic conditions demonstrated, proving chromatographic potential of the new column format, with run-to-run retention time reproducibility of below 1%. - Highlights: • Novel PS-DVB modified photonic crystal fibres for in-capillary micro-extraction. • New method for micro-extraction of PAHs and HPLC-FL detection at sub-ppb levels. • Demonstration of PS-DVB modified photonic crystal fibres for capillary bioseparations.

  17. Silica-based monolithic capillary columns modified by liposomes for characterization of analyte–liposome interactions by capillary liquid chromatography

    Czech Academy of Sciences Publication Activity Database

    Moravcová, Dana; Planeta, Josef; Wiedmer, S. K.

    2013-01-01

    Roč. 1317, SI (2013), s. 159-166 ISSN 0021-9673 R&D Projects: GA MV VG20112015021; GA ČR(CZ) GAP206/11/0138 Institutional support: RVO:68081715 Keywords : monolithic silica capillary column * immobilized liposomes * biomimicking stationary phase Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.258, year: 2013

  18. The design and test of ellipsoidal glass capillaries as condensers for X-ray microscope

    International Nuclear Information System (INIS)

    Tian Jinping; Li Wenjie; Chen Jie; Liu Gang; Xiong Ying; Liu Longhua; Huang Xinlong; Tian Yangchao

    2008-01-01

    A high resolution X-ray microscope endstation was constructed on a wiggler beamline at the National Synchrotron Radiation Laboratory (NSRL). Parameters of the ellipsoidal glass capillaries as condensers were calculated and designed based on the illumination requests in the X-ray microscope system. Performance of the ellipsoidal glass capillaries was tested. The results indicate that the beam size agrees with the designed parameters and focus efficiencies of the ellipsoidal glass capillary condensers are better than 85%. (authors)

  19. Experimental investigation of virus and clay particles cotransport in partially saturated columns packed with glass beads.

    Science.gov (United States)

    Syngouna, Vasiliki I; Chrysikopoulos, Constantinos V

    2015-02-15

    Suspended clay particles in groundwater can play a significant role as carriers of viruses, because, depending on the physicochemical conditions, clay particles may facilitate or hinder the mobility of viruses. This experimental study examines the effects of clay colloids on the transport of viruses in variably saturated porous media. All cotransport experiments were conducted in both saturated and partially saturated columns packed with glass beads, using bacteriophages MS2 and ΦX174 as model viruses, and kaolinite (KGa-1b) and montmorillonite (STx-1b) as model clay colloids. The various experimental collision efficiencies were determined using the classical colloid filtration theory. The experimental data indicated that the mass recovery of viruses and clay colloids decreased as the water saturation decreased. Temporal moments of the various breakthrough concentrations collected, suggested that the presence of clays significantly influenced virus transport and irreversible deposition onto glass beads. The mass recovery of both viruses, based on total effluent virus concentrations, was shown to reduce in the presence of suspended clay particles. Furthermore, the transport of suspended virus and clay-virus particles was retarded, compared to the conservative tracer. Under unsaturated conditions both clay particles facilitated the transport of ΦX174, while hindered the transport of MS2. Moreover, the surface properties of viruses, clays and glass beads were employed for the construction of classical DLVO and capillary potential energy profiles, and the results suggested that capillary forces play a significant role on colloid retention. It was estimated that the capillary potential energy of MS2 is lower than that of ΦX174, and the capillary potential energy of KGa-1b is lower than that of STx-1b, assuming that the protrusion distance through the water film is the same for each pair of particles. Moreover, the capillary potential energy is several orders of

  20. Transmission of fast highly charged ions through straight and tapered glass capillaries

    International Nuclear Information System (INIS)

    Ayyad, Asma M; Keerthisinghe, D; Kayani, A; Tanis, J A; Dassanayake, B S; Ikeda, T

    2013-01-01

    The transmission of 1 and 3 MeV protons through a borosilicate straight glass capillary and a tapered glass capillary was investigated. The straight capillary had a diameter of ∼0.18 mm and a length of ∼14.4 mm, while the tapered capillary had an inlet diameter of ∼0.71 mm, an outlet diameter of ∼0.10 mm and a length of ∼28 mm. The results show that the 1 and 3 MeV protons traverse through both samples without energy loss, while the tapered capillary showed better transmission than the straight capillary. (paper)

  1. Controlled crosslinking of trimethylolpropane trimethacrylate for preparation of organic monolithic columns for capillary liquid chromatography.

    Science.gov (United States)

    Gama, Mariana R; Aggarwal, Pankaj; Lee, Milton L; Bottoli, Carla B G

    2017-11-01

    Organic monolithic columns based on single crosslinking of trimethylolpropane trimethacrylate (TRIM) monomer were prepared in a single step by living/controlled free-radical polymerization. Full optimization of the preparation, such as using different percentages of TRIM and different amounts of radical promoter as well as various porogen solvents were explored. The resulting monolithic columns were characterized by scanning electronic microscopy and nitrogen sorption for structure morphology studies and surface area measurements, respectively. Using capillary liquid chromatography, 150 μm i.d. columns were applied to separate a mixture of small hydrophobic molecules. The results indicated that column performance is highly sensitive to the type and the amount of porogen solvents used in the polymerization mixture composition. Good resolution factors and methylene selectivity were obtained, indicating the promising potential of this material for capillary liquid chromatography separations. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. A novel ionic liquid monolithic column and its separation properties in capillary electrochromatography

    International Nuclear Information System (INIS)

    Wang Yu; Deng Qiliang; Fang Guozhen; Pan Mingfei; Yu Yang; Wang Shuo

    2012-01-01

    Highlights: ► ILs as functional monomer for capillary monolithic column. ► Separation of alkylbenzenes, thiourea analogues, and amino acids. ► The column generate a stable reversed EOF from pH 2.0 to 12.0. ► The column efficiency of 147,000 plates m −1 was obtained for thiourea. - Abstract: A novel ionic liquid (IL) monolithic capillary column was successfully prepared by thermal free radical copolymerization of IL (1-vinyl-3-octylimidazolium chloride, ViOcIm + Cl − ) together with lauryl methacrylate (LMA) as the binary functional monomers and ethylene dimethacrylate (EDMA) as the cross-linker in binary porogen. The proportion of monomers, porogens and cross-linker in the polymerization mixture was optimized in detail. The resulting IL-monolithic column could not only generate a stable reversed electroosmotic flow (EOF) in a wide pH range (2.0–12.0), but also effectively eliminate the wall adsorption of the basic analytes. The obtained IL-monolithic columns were examined by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR). These results indicated that the IL-monolithic capillary column possessed good pore properties, mechanical stability and permeability. The column performance was also evaluated by separating different kinds of compounds, such as alkylbenzenes, thiourea and its analogues, and amino acids. The lowest plate height of ∼6.8 μm was obtained, which corresponded to column efficiency (theoretical plates, N) of ∼147,000 plates m −1 for thiourea. ILs, as a new type of functional monomer, present a promising option in the fabrication of the organic polymer-based monolithic columns in CEC.

  3. The effect of temperature on guiding of slow highly charged ions through a mesoscopic glass capillary

    International Nuclear Information System (INIS)

    Bereczky, R J; Tökési, K; Kowarik, G; Ladinig, F; Schrempf, D; Aumayr, F

    2012-01-01

    We present first temperature dependent transmission measurements of slow highly charged ions through a single, straight Duran glass capillary with a high aspect ratio. By changing the temperature of the glass capillary the electrical conductivity of the Duran can be varied by several orders of magnitude. This held the promise to investigate the effect of conductivity on particle transport (build-up and removal of charge patches) through capillaries in more details.

  4. SEPARATION OF OCTYLPHENOL POLYETHER ALCOHOLS SURFACTANTS BY CAPILLARY COLUMN SFC AND HPLC

    Science.gov (United States)

    Separation of nonionic octylphenol polyether alcohols (OPA) by supercritical fluid chromatography (SFC) and HPLC is described. Using a density programming and a 50-μm i.d. capillary column, a total of 18 group oligomers was separated. The effects of the operating parameters, such...

  5. Sol-gel open tubular ODS columns with reversed electroosmotic flow for capillary electrochromatography.

    Science.gov (United States)

    Hayes, J D; Malik, A

    2001-03-01

    Sol-gel chemistry was successfully used for the fabrication of open tubular columns with surface-bonded octadecylsilane (ODS) stationary-phase coating for capillary electrochromatography (OT-CEC). Following column preparations, a series of experiments were performed to investigate the performance of the sol-gel coated ODS columns in OT-CEC. The incorporation of N-octadecyldimethyl[3-(trimethoxysilyl)propyl]ammonium chloride as one of the sol-gel precursors played an important role in the electrochromatographic performance of the prepared columns. This chemical reagent possesses a chromatographically favorable, bonded ODS moiety, in conjunction with three methoxy groups allowing for sol-gel reactivity. In addition, a positively charged nitrogen atom is present in the molecular structure of this reagent and provides a positively charged capillary surface responsible for the reversed electroosmotic flow (EOF) in the columns during CEC operation. Comparative studies involving the EOF within such sol-gel ODS coated and uncoated capillaries were performed using acetonitrile and methanol as the organic modifiers in the mobile phase. The use of a deactivating reagent, phenyldimethylsilane, in the sol-gel solution was evaluated. Efficiency values of over 400,000 theoretical plates per meter were achieved in CEC on a 64 cm x 25 microm i.d. sol-gel ODS open tubular column. Test mixtures of polycyclic aromatic hydrocarbons, benzene derivatives, and aromatic aldehydes and ketones were used to evaluate the CEC performances of both nondeactivated and deactivated open tubular sol-gel columns. The effects of mobile-phase organic modifier contents and pH on EOF in such columns were evaluated. The prepared sol-gel ODS columns are characterized by switchable electroosmotic flow. A pH value of approximately 8.5 was found correspond to the isoelectric point for the prepared sol-gel ODS coatings.

  6. A novel in situ strategy for the preparation of a β-cyclodextrin/polydopamine-coated capillary column for capillary electrochromatography enantioseparations.

    Science.gov (United States)

    Guo, Heying; Niu, Xiaoying; Pan, Congjie; Yi, Tao; Chen, Hongli; Chen, Xingguo

    2017-06-01

    Inspired by the chiral recognition ability of β-cyclodextrin and the natural adhesive properties of polydopamine under alkaline conditions, in this study, a rapid and in situ modification strategy was developed to fabricate β-cyclodextrin/polydopamine composite material coated-capillary columns for open tubular capillary electrochromatography. The results of scanning electron microscopy, FTIR spectroscopy, streaming potential, and electro-osmotic flow studies indicated that β-cyclodextrin/polydopamine was successfully fixed on the inner wall of the capillary column. This coating can be achieved within 1 h affording a greatly reduced capillary preparation time. The performance of the β-cyclodextrin/polydopamine-coated capillary was validated by the analysis of seven pairs of chiral analytes, namely epinephrine, norepinephrine, isoprenaline, terbutaline, verapamil, tryptophane, carvedilol. Good enantioseparation efficiencies were achieved for all. For three consecutive runs, the relative standard deviations for the migration times of the analytes for intraday, interday, and column-to-column repeatability were in the range of 0.41-1.74, 1.03-4.18, and 1.66-8.24%, respectively. Moreover, the separation efficiency of the β-cyclodextrin/polydopamine-coated capillary column did not decrease obviously over 90 runs. The strategy should also be feasible to introduce and immobilize other chiral selectors on the inner walls surface of capillary columns. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. A novel ionic liquid monolithic column and its separation properties in capillary electrochromatography.

    Science.gov (United States)

    Wang, Yu; Deng, Qi-Liang; Fang, Guo-Zhen; Pan, Ming-Fei; Yu, Yang; Wang, Shuo

    2012-01-27

    A novel ionic liquid (IL) monolithic capillary column was successfully prepared by thermal free radical copolymerization of IL (1-vinyl-3-octylimidazolium chloride, ViOcIm(+)Cl(-)) together with lauryl methacrylate (LMA) as the binary functional monomers and ethylene dimethacrylate (EDMA) as the cross-linker in binary porogen. The proportion of monomers, porogens and cross-linker in the polymerization mixture was optimized in detail. The resulting IL-monolithic column could not only generate a stable reversed electroosmotic flow (EOF) in a wide pH range (2.0-12.0), but also effectively eliminate the wall adsorption of the basic analytes. The obtained IL-monolithic columns were examined by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR). These results indicated that the IL-monolithic capillary column possessed good pore properties, mechanical stability and permeability. The column performance was also evaluated by separating different kinds of compounds, such as alkylbenzenes, thiourea and its analogues, and amino acids. The lowest plate height of ~6.8 μm was obtained, which corresponded to column efficiency (theoretical plates, N) of ~147,000 plates m(-1) for thiourea. ILs, as a new type of functional monomer, present a promising option in the fabrication of the organic polymer-based monolithic columns in CEC. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Methacrylate monolithic columns functionalized with epinephrine for capillary electrochromatography applications.

    Science.gov (United States)

    Carrasco-Correa, Enrique Javier; Ramis-Ramos, Guillermo; Herrero-Martínez, José Manuel

    2013-07-12

    Epinephrine-bonded polymeric monoliths for capillary electrochromatography (CEC) were developed by nucleophilic substitution reaction of epoxide groups of poly(glycidyl-methacrylate-co-ethylenedimethacrylate) (poly(GMA-co-EDMA)) monoliths using epinephrine as nucleophilic reagent. The ring opening reaction under dynamic conditions was optimized. Successful chemical modification of the monolith surface was ascertained by in situ Raman spectroscopy characterization. In addition, the amount of epinephrine groups that was bound to the monolith surface was evaluated by oxidation of the catechol groups with Ce(IV), followed by spectrophotometric measurement of unreacted Ce(IV). About 9% of all theoretical epoxide groups of the parent monolith were bonded to epinephrine. The chromatographic behavior of the epinephrine-bonded monolith in CEC conditions was assessed with test mixtures of alkyl benzenes, aniline derivatives and substituted phenols. In comparison to the poly(GMA-co-EDMA) monoliths, the epinephrine-bonded monoliths exhibited a much higher retention and slight differences in selectivity. The epinephrine-bonded monolith was further modified by oxidation with a Ce(IV) solution and compared with the epinephrine-bonded monoliths. The resulting monolithic stationary phases were evaluated in terms of reproducibility, giving RSD values below 9% in the parameters investigated. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. In situ preparation of multilayer coated capillary column with HKUST-1 for separation of neutral small organic molecules by open tubular capillary electrochromatography.

    Science.gov (United States)

    Xu, Yin-Yin; Lv, Wen-Juan; Ren, Cui-Ling; Niu, Xiao-Ying; Chen, Hong-Li; Chen, Xing-Guo

    2018-01-12

    The popularity of novel nanoparticles coated capillary column has aroused widespread attention of researchers. Metal organic frameworks (MOFs) with special structure and chemical properties have received great interest in separation sciences. This work presents the investigation of HKUST-1 (Hong Kong University of Science and Technology-1, called Cu 3 (BTC) 2 or MOF-199) nanoparticles as a new type of coating material for capillary electrochromatography. For the first time, three layers coating (3-LC), five layers coating (5-LC), ten layers coating (10-LC), fifteen layers coating (15-LC), twenty layers coating(20-LC) and twenty-five layers coating (25-LC) capillary columns coated with HKUST-1 nanoparticles were synthesized by covalent bond with in situ, layer-by-layer self-assembly approach. The results of scanning electron microscopy (SEM), X-ray diffraction (XRD) and plasma atomic emission spectrometry (ICP-AES) indicated that HKUST-1 was successfully grafted on the inner wall of the capillary. The separating performances of 3-LC, 5-LC, 10-LC, 15-LC, 20-LC and 25-LC open tubular (OT) capillary columns were studied with some neutral small organic molecules. The results indicated that the neutral small organic molecules were separated successfully with 10-LC, 15-LC and 20-LC OT capillary columns because of the size selectivity of lattice aperture and hydrophobicity of organic ligands. In addition, 10-LC and 15-LC OT capillary columns showed better performance for the separation of certain phenolic compounds. Furthermore, 10-LC, 15-LC and 20-LC OT capillary columns exhibited good intra-day repeatability with the relative standard deviations (RSDs; %) of migration time and peak areas lying in the range of 0.3-1.2% and 0.5-4.2%, respectively. For inter-day reproducibility, the RSDs of the three OT capillary columns were found to be lying in the range of 0.3-5.5% and 0.3-4.5% for migration time and peak area, respectively. The RSDs of retention times for column-to-column

  10. Flow rate dependent extra-column variance from injection in capillary liquid chromatography.

    Science.gov (United States)

    Aggarwal, Pankaj; Liu, Kun; Sharma, Sonika; Lawson, John S; Dennis Tolley, H; Lee, Milton L

    2015-02-06

    Efficiency and resolution in capillary liquid chromatography (LC) can be significantly affected by extra-column band broadening, especially for isocratic separations. This is particularly a concern in evaluating column bed structure using non-retained test compounds. The band broadening due to an injector supplied with a commercially available capillary LC system was characterized from experimental measurements. The extra-column variance from the injection valve was found to have an extra-column contribution independent of the injection volume, showing an exponential dependence on flow rate. The overall extra-column variance from the injection valve was found to vary from 34 to 23 nL. A new mathematical model was derived that explains this exponential contribution of extra-column variance on chromatographic performance. The chromatographic efficiency was compromised by ∼130% for a non-retained analyte because of injection valve dead volume. The measured chromatographic efficiency was greatly improved when a new nano-flow pumping system with integrated injection valve was used. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Retention behavior of neutral solutes in pressurized flow-driven capillary electrochromatography using an ODS column.

    Science.gov (United States)

    Nakagawa, Hiroyuki; Kitagawa, Shinya; Araki, Shuki; Ohtani, Hajime

    2006-02-01

    Several alkyl benzenes are separated by pressurized flow-driven capillary electrochromatography using a temperature-controlled capillary column packed with octadecyl siloxane-modified silica gel, and the effect of applied voltage on the retention is investigated. The van't Hoff plot shows good linearity at the column temperature between 305 and 330 K under applications from -6 to +6 kV. The applied voltage causes a relatively large variation in the enthalpy and the entropy of transfer of the solute from the mobile phase to the stationary phase (> 20%). However, the direction of variation in the enthalpy is almost opposite to that in the entropy, both of which might compensate each other. Therefore, the retention factor is not significantly varied (< 4%) by the application of voltage.

  12. Post-column derivatization capillary electrochromatography for detection of biogenic amines in tuna-meat.

    Science.gov (United States)

    Oguri, Shigeyuki; Okuya, Yukie; Yanase, Yukiko; Suzuki, Sayaka

    2008-08-15

    A system to perform post-column derivatization capillary electrochromatography (CEC) was developed for the first time. The system mainly included a 4-microm (O.D.) silica packed column (200 mm effective length x 0.1 mm inner diameter I.D.) with micro-magnetic particles (MMPs) frits, a T-junction connector, an in-line fluorescence detector and a high-voltage power supply. The system was evaluated by using histamine (HA) as a standard biogenic amine for this study. A 5 microM HA solution was loaded at the anodic site of the capillary column by applying 3 kV for 5s. Then, HA was electrophoretically eluted with a 20mM phosphate buffer (pH 7) by applying 3 kV, and was derivatized with 3mM o-phthalaldehyde (OPA)/N-acetylcysteine (NAC) in 100 mM borate (pH 10), which was continuously delivered through the reagent-loading capillary tube by gravity into the T-junction connector. HA derivative was finally detected with the in-line fluorescence detector (lambda(Ex)=340 nm, lambda(Em)=450 nm) at 9.7 min after sample loading. To test the utility of this system, it was next employed for its ability to detect the presence of HA and other kinds of biogenic amines, including cadaverine (Cad), spermidine (Spm) and tyramine (Tyr) in tuna-meat, once the validity of the method had been confirmed.

  13. Polydopamine-coated open tubular column for the separation of proteins by capillary electrochromatography.

    Science.gov (United States)

    Xiao, Xing; Wang, Wentao; Chen, Jia; Jia, Li

    2015-08-01

    The separation and determination of proteins in food is an important aspect in food industry. Inspired by the self-polymerization of dopamine under alkaline conditions and the natural adhesive properties of polydopamine, in this paper, a simple and economical method was developed for the preparation of polydopamine-coated open tubular column, in which ammonium persulfate was used as the source of oxygen to induce and facilitate the polymerization of dopamine to form polydopamine. In comparison with a naked fused-silica capillary, the direction and magnitude of the electro-osmotic flow of the as-prepared polydopamine-coated open tubular column could be manipulated by varying the pH values of background solutions due to the existence of amine and phenolic hydroxyl groups on polydopamine coating. The surface morphology of the polydopamine-coated open tubular column was studied by scanning electron microscopy, and the thickness of polydopamine coating was 106 nm. The performance of the polydopamine-coated open tubular column was validated by analysis of proteins. The relative standard deviations of migration times of proteins representing run-to-run, day-to-day, and column-to-column were less than 3.5%. In addition, the feasibility of the polydopamine-coated open tubular column for real samples was verified by the separation of proteins in chicken egg white and pure milk. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Validity of using modified capillary column with larger diameter to study the Cs diffusion in local Taiwan laterite

    International Nuclear Information System (INIS)

    Tsing-Hai Wang; National Tsing Hua University, Hsinchu, Taiwan; Wen-Chun Yeh; Shih-Chin Tsai; Yi-Lin Jan; Shi-Ping Teng

    2008-01-01

    We have examined the working diameter of capillary columns with diameter of 5, 7, 10 and 20 mm. These modified capillary columns were carefully filled with local Taiwan laterite (LTL). The porosity and density of these packed columns was 0.51±0.02 g/g and 1.27±0.05 g/cm 3 , respectively. The diffusion experiments were then carried out in synthetic groundwater with Cs loading of 0.1mM at room temperature. Experimental results have shown that the diffusion profiles of modified capillary columns fit Fick's second law very well. This result revealed that the working diameter of a capillary column can be expanded to at least to 20 mm without affecting the validity of the derived diffusion coefficients. Among these columns, the ones with 5 mm diameter show the most consistent results of the derived K d , apparent and effective diffusion coefficients. Although the derived distribution and effective diffusion coefficients slightly decrease as the diameter of these columns increases due to the increase of the solid/liquid ratio. These values are still informative of the Cs diffusion in local Taiwan laterite. Moreover, our results clearly demonstrate the potential of using 'modified capillary method' to study the diffusion behaviors of concerned radionuclide because columns with large diameter enable the filling with more versatile geological substances. (author)

  15. Exploring the effect of mesopore size reduction on the column performance of silica-based open tubular capillary columns.

    Science.gov (United States)

    Hara, Takeshi; Futagami, Shunta; De Malsche, Wim; Baron, Gino V; Desmet, Gert

    2018-06-01

    We report on a modification in the hydrothermal treatment process of monolithic silica layers used in porous-layered open tubular (PLOT) columns. Lowering the temperature from the customary 95 °C to 80 °C, the size of the mesopores reduced by approximately about 35% from 12-13.5 nm to 7.5-9 nm, while the specific pore volume essentially remains unaltered. This led to an increase of the specific surface area (SA) of about 40%, quasi-independent of the porous layer thickness. The increased surface area provided a corresponding increase in retention, somewhat more (48%) than expected based on the increase in SA for the thin layer columns, and somewhat less than expected (34%) for the thick layer columns. The recipes were applied in 5 μm i.d.-capillaries with a length of 60 cm. Efficiencies under retained conditions amounted up to N = 137,000 for the PLOT column with a layer thickness (d f ) of 300 nm and to N = 109,000 for the PLOT column with d f  = 550 nm. Working under conditions of similar retention, the narrow pore/high SA columns produced with the new 80 °C recipe generated the same number of theoretical plates as the wide pore size/low SA columns produced with the 95 °C recipe. This shows the 80 °C-hydrothermal treatment process allows for an increase in the phase ratio of the PLOT columns without affecting their intrinsic mass transfer properties and separation kinetics. This is further corroborated by the fact that the plate height curves generated with the new and former recipe can both be well-fitted with the Golay-Aris equation without having to change the intra-layer diffusion coefficient. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Characterization of polymer-based monolithic capillary columns by inverse size-exclusion chromatography and mercury-intrusion porosimetry

    NARCIS (Netherlands)

    Urban, J.; Eeltink, S.; Jandera, P.; Schoenmakers, P.J.

    2008-01-01

    Organic-polymer monolithic capillary columns were prepared in fused-silica capillaries by a radical copolymerization reaction of butyl methacrylate and ethylene dimethacrylate monomers in the presence of 1,4-butanediol and 1-propanol as porogen solvents and azobisisobutyronitrile as the initiator.

  17. Capillary trap column with strong cation-exchange monolith for automated shotgun proteome analysis.

    Science.gov (United States)

    Wang, Fangjun; Dong, Jing; Jiang, Xiaogang; Ye, Mingliang; Zou, Hanfa

    2007-09-01

    A 150 microm internal diameter capillary monolithic column with a strong cation-exchange stationary phase was prepared by direct in situ polymerization of ethylene glycol methacrylate phosphate and bisacrylamide in a trinary porogenic solvent consisting dimethylsulfoxide, dodecanol, and N,N'-dimethylformamide. This phosphate monolithic column exhibits higher dynamic binding capacity, faster kinetic adsorption of peptides, and more than 10 times higher permeability than the column packed with commercially available strong cation-exchange particles. It was applied as a trap column in a nanoflow liquid chromatography-tandem mass spectrometry system for automated sample injection and online multidimensional separation. It was observed that the sample could be loaded at a flow rate as high as 40 microL/min with a back pressure of approximately 1300 psi and without compromising the separation efficiency. Because of its good orthogonality to the reversed phase separation mechanism, the phosphate monolithic trap column was coupled with a reversed-phase column for online multidimensional separation of 19 microg of the tryptic digest of yeast proteins. A total of 1522 distinct proteins were identified from 5608 unique peptides (total of 54,780 peptides) at the false positive rate only 0.46%.

  18. Electrochromatographic performance of graphene and graphene oxide modified silica particles packed capillary columns.

    Science.gov (United States)

    Zhao, Hongyan; Wang, Yizhou; Zhang, Danyu; Cheng, Heyong; Wang, Yuanchao

    2018-04-01

    Graphene oxide functionalized silica microspheres (GO@SiO 2 ) were synthesized based on condensation reaction between amino from aminosilica particles and carboxyl groups from GO. Reduction of GO@SiO 2 with hydrazinium hydroxide generated graphene modified silica particles (G@SiO 2 ). GO@SiO 2 and G@SiO 2 packed capillary columns for capillary electrochromatography were thereafter fabricated by pressure slurry packing with single-particle frits. GO of 0.3 mg/mL in dispersion solution for GO@SiO 2 synthesis was considered as a compromise between retaining and column efficiency whereas GO@SiO 2 of 20 mg/mL in slurries for column packing was chosen for a homogenous and tight bed. Optimum mobile phases were acquired considering both electroosmotic flow and resolution at an applied voltage of -6 kV as the following: acetonitrile/phosphate buffer (10 mM, pH 7.0), 75:25 (v/v) for polycyclic aromatic hydrocarbons and 50:50 (v/v) for aromatic compounds. A comparison was made between electrochromatographic performances for three PAHs (naphthalene, fluorene and phenanthrene) and three aromatic compounds of various polarities (toluene, aniline and phenol) on bare aminosilica, GO@SiO 2 and G@SiO 2 packed columns, which proved the contribution of alone or combinational actions of solvophobic effect and π-π electron stacking as well as hydrogen bonds to retaining behaviors by GO@SiO 2 and G@SiO 2 . Well over-run, over-day and over-column precisions (retention time: 0.3-1.4, 1.1-3.8 and 2.8-5.2%, respectively; peak area: 2.6-6.5, 4.8-8.3 and 6.5-12.6%, respectively) of GO@SiO 2 packed columns were a powerful proof for good reproducibility. Analytical characteristics of GO@SiO 2 packed capillary columns in CEC analysis of fresh water were evaluated with respect to linearity (R 2 = 0.9961-0.9989) over the range 0.1 to 100 mg/L and detection limits of 9.5 for naphthalene, 12.6 for fluorene and 16.2 μg/L for phenanthrene. Further application to fresh water increased the

  19. High Efficiency Robust Open Tubular Capillary Electrochromatography Column for the Separation of Peptides

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Faiz; Cheong, Won Jo [Inha University, Incheon (Korea, Republic of)

    2016-08-15

    In this study, the carefully designed tri-component copolymer layer was fabricated onto the inner surface of a pretreated silica capillary (52 cm effective length, 50 μm id). The initiator moieties were incorporated onto the capillary inner surface by reaction with 4-chloromehtylphenyl isocyanate followed by sodium diethyl dithiocarbamate. Next, RAFT copolymerization was held upon the initiator moieties and a thin polymer film was made. The observed peak capacity was, of course, lower than those of the state-of-the art gradient HPLC systems. The UPLC system operated in the long gradient elution mode with a long narrow column of sub-3 μm packed particles could achieve the impressive high peak capacity of ca. 1000. On the other hand, a system with a 20 cm column of 0.8 μm particles could achieve a peak capacity of 220 (comparable to our result) under a pressure of 20 000 psi in a gradient time of 20 min. It should be noted that the operational conditions of this study has been optimized to obtain the best column separation efficiency. It was also operated in the isocratic elution mode. A better peak capacity is expected if the operational conditions are tuned to the optimum peak capacity.

  20. Capillary electrochromatography of inorganic cations in open tubular columns with a controllable capacity multilayered stationary phase architecture.

    Science.gov (United States)

    Kubán, Pavel; Kubán, Petr; Kubán, Vlastimil; Hauser, Peter C; Bocek, Petr

    2008-05-09

    In this paper capillary electrochromatography of alkali and alkaline-earth metal cations in open tubular capillary columns is described. Capillary columns are prepared by coating fused silica capillaries of 75 microm I.D. with poly(butadiene-maleic acid) copolymer (PBMA) in multiple layers. Thermally initiated radical polymerization is used to crosslink the stationary phase. Capillary columns with different number of stationary phase layers can be prepared and allow for the adjustment of separation selectivity in the electrochromatographic mode. Fast and sensitive separations of common inorganic cations are achieved in less than 6 min in a 60 cm capillary column with on-column capacitively coupled contactless conductivity detector. Limits of detection (S/N=3) for the determination of alkali and alkaline-earth metal cations range from 0.3 to 2.5 microM and repeatability is better than 0.5, 4.5 and 6.1% for migration times, peak heights and peak areas, respectively.

  1. Capillary column switching restricted-access media-liquid chromatography-electrospray ionization-tandem mass spectrometry system for simultaneous and direct analysis of drugs in biofluids.

    Science.gov (United States)

    Santos-Neto, Alvaro J; Markides, Karin E; Sjöberg, Per J R; Bergquist, Jonas; Lancas, Fernando M

    2007-08-15

    Capillary online restricted-access media-liquid chromatography-electrospray ionization-tandem mass spectrometry (RAM-LC-ESI-MS/MS) for direct analysis of drugs and metabolites spiked in biological fluids was developed. Using a column switching setup it was possible to perform effective sample preparation and analysis of raw biological fluids (plasma and urine) without matrix effects in the electrospray mass spectrometric detection step. The peak focusing efficiency of the extraction column was more effective in backflush compared to foreflush mode. The system was able to concentrate diminished samples of polar drugs and their metabolites reaching quantifiable results as low as 1 ng/mL utilizing a sample volume of only 333 nL of biofluids. New column hardware was developed to circumvent clogging problems experienced with plasma injections. The glass fiber filter frit, which is commonly used, was replaced with a short piece of 20 microm i.d. fused silica capillary. The extraction columns were able to handle up to 60 injections and showed a high loading capacity, making the saturation of the MS detector the limiting factor on the linear dynamic range. The simultaneous separation and detection of 10 drugs and metabolites was obtained in 8 min of analysis, including the online sample preparation and enrichment step.

  2. Fabrication of single-walled carbon nanohorns incorporated a monolithic column for capillary electrochromatography.

    Science.gov (United States)

    Zhao, Hongyan; Wang, Yizhou; Cheng, Heyong; Wang, Yuanchao

    2017-08-01

    Single-walled carbon nanohorns have received great interest for their unique properties and diverse potential applications. Herein, we demonstrated the feasibility of single-walled carbon nanohorns incorporated poly(styrene-divinylbenzene) monolith as the stationary phase for capillary electrochromatography, which were prepared by one-step in situ copolymerization. Single-walled carbon nanohorns were dispersed in styrene to give a stable and homogeneous suspension. The monolithic column gave effective separation for a wide range of aromatic compounds, which was based on hydrophobicity and π-π electrostatic stacking of single-walled carbon nanohorns. The precisions of migration time and peak area varied in the ranges of 1.4-1.9% for intraday trials and 1.7-3.5% for interday trials, and 3.2-6.7% for intraday trials and 4.1-7.4% for interday trials, and 3.6-7.2% for inter-column trials and 5.2-21.3% for inter-column trials, respectively, indicating the good reproducibility of single-walled carbon nanohorns embedded monolithic columns. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Extreme degree of ionization in homogenous micro-capillary plasma columns heated by ultrafast current pulses.

    Science.gov (United States)

    Avaria, G; Grisham, M; Li, J; Tomasel, F G; Shlyaptsev, V N; Busquet, M; Woolston, M; Rocca, J J

    2015-03-06

    Homogeneous plasma columns with ionization levels typical of megaampere discharges are created by rapidly heating gas-filled 520-μm-diameter channels with nanosecond rise time current pulses of 40 kA. Current densities of up to 0.3  GA cm^{-2} greatly increase Joule heating with respect to conventional capillary discharge Z pinches, reaching unprecedented degrees of ionization for a high-Z plasma column heated by a current pulse of remarkably low amplitude. Dense xenon plasmas are ionized to Xe^{28+}, while xenon impurities in hydrogen discharges reach Xe^{30+}. The unique characteristics of these hot, ∼300:1 length-to-diameter aspect ratio plasmas allow the observation of unexpected spectroscopic phenomena. Axial spectra show the unusual dominance of the intercombination line over the resonance line of He-like Al by nearly an order of magnitude, caused by differences in opacities in the axial and radial directions. These plasma columns could enable the development of sub-10-nm x-ray lasers.

  4. Preparation of β-cyclodextrin-gold nanoparticles modified open tubular column for capillary electrochromatographic separation of chiral drugs.

    Science.gov (United States)

    Zhou, Li; Jiang, Shenmeng; Zhang, Xue; Fang, Linlin; Guo, Xingjie

    2018-04-01

    In this paper, β-cyclodextrin (β-CD) modified gold nanoparticles (AuNPs) coated open tubular column (OT column) was prepared for capillary electrochromatography. The open tubular column was constructed through self-assembly of gold nanoparticles on 3-mercaptopropyl-trimethoxysilane (MPTMS) prederivatized capillary and subsequent modification of thiols β-cyclodextrin (SH-β-CD). Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and ultraviolet visible spectroscopy were carried out to characterize the prepared open tubular column and synthesized gold nanoparticles. By comparing different coating times of gold nanoparticles and thiols β-cyclodextrin, we got the optimal conditions for preparing the open tubular column. Also, the separation parameters were optimized including buffer pH, buffer concentration and applied voltage. Separation effectiveness of open tubular column was verified by the separation of four pairs of drug enantiomers including bifonazole, fexofenadine, omeprazole and lansoprazole, and satisfactory separation results were achieved for these analytes studied. In addition, the column showed good stability and repeatability. The relative standard deviation values less than 5% were obtained through intra-day, inter-day, and column-to-column investigations. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Nano-amylose-2,3-bis(3,5-dimethylphenylcarbamate)-silica hybrid sol immobilized on open tubular capillary column for capillary electrochromatography enantioseparation.

    Science.gov (United States)

    Sun, Yaming; Wu, Qi; Shi, Xiaofeng; Gao, Jie; Dong, Shuqing; Zhao, Liang

    2018-04-01

    The chiral organic-inorganic hybrid materials can exhibit a high loading, and the chiral selector nanoparticles can create efficient stationary phases for open-tubular capillary electrochromatography (OT-CEC). Hence, a novel protocol for the preparation of an OT column coated with nano-amylose-2,3-bis(3,5-dimethylphenylcarbamate) (nano-ABDMPC)-silica hybrid sol through in situ layer-by-layer self-assembly method was developed for CEC enantioseparation. By controlling the assembly cycle number of nano-ABDMPC-silica hybrid sol, a homogeneous, dense and stable coating was successfully prepared, which was confirmed by SEM and elemental analysis. As the main parameter influencing the chiral separating effect, the nano-ABDMPC bearing 3-(triethoxysilyl)propyl residues concentration was investigated. The experimental results showed that 10.0 mg/mL nano-ABDMPC bearing 3-(triethoxysilyl)propyl residues coated OT capillary column possessed chiral recognition ability toward the six enantiomers (phenylalanine, tyrosine, tryptophan, phenethyl alcohol, 1-phenyl-2-propanol, and Tröger's base) at some of the different conditions tested. Additionally, the coated OT column revealed adequate repeatability concerning run-to-run, day-to-day and column-to-column. These results demonstrated the promising applicability of nano-ABDMPC-silica hybrid sol coated OT column in CEC enantioseparations. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. A new vertex detector made of glass capillaries

    International Nuclear Information System (INIS)

    Annis, P.; Bonekaemper, D.; Buontempo, S.; Ereditato, A.; Fabre, J.D.; Fiorillo, G.; Frekers, D.; Frenkel, A.; Galeazzi, F.; Garufi, F.; Goldberg, J.; Golovkin, S.; Hoepfner, K.; Konijn, J.; Kozarenko, E.; Kreslo, I.; Liberti, B.; Martellotti, G.; Medvedkov, A.; Mommaert, C.; Penso, G.; Petukhov, Y.; Rondeshagen, D.; Tyukov, V.; Vasilchenko, V.; Vilain, P.; Wilquet, G.; Wolff, T.; Wong, H.

    1997-01-01

    We have developed a new detector technique that allows high quality imaging of ionizing particle tracks with very high spatial and time resolution. Central to this technique are liquid-core fibres of about 20 μm diameter read out by an optoelectronic system including a CCD. The fibres act simultaneously as target, detector and light guides. A large-volume prototype, consisting of 5 x 10 5 capillaries of 20 μm diameter and 180 cm length, has been tested in the CERN wide-band neutrino beam. A sample of high-multiplicity neutrino interactions was recorded, demonstrating the imaging quality of this detector. First results from the reconstruction of these events are reported. A track residual of 28 μm and a vertex resolution of 30 μm has been achieved. Future applications of capillary detectors for neutrino and beauty physics are being investigated within the framework of the RD46 collaboration. (orig.)

  7. A purge-and-trap capillary column gas chromatographic method for the measurement of halocarbons in water and air

    Energy Technology Data Exchange (ETDEWEB)

    Happell, J.D.; Wallace, D.W.R.; Wills, K.D.; Wilke, R.J.; Neill, C.C.

    1996-06-01

    This report describes an automated, accurate, precise and sensitive capillary column purge- and -trap method capable of quantifying CFC-12, CFC-11, CFC-113, CH{sub 3}CCL{sub 3}, and CCL{sub 4} during a single chromatographic analysis in either water or gas phase samples.

  8. Water movement in glass bead porous media: 1. Experiments of capillary rise and hysteresis

    Science.gov (United States)

    Lu, T. X.; Biggar, J. W.; Nielsen, D. R.

    1994-12-01

    Experimental observations of capillary rise and hysteresis of water or ethanol in glass beads are presented to improve our understanding of those physical processes in porous media. The results provide evidence that capillary rise into porous media cannot be fully explained by a model of cylinders. They further demonstrate that the "Ink bottle" model does not provide an adequate explanation of hysteresis. Glass beads serving as a model for ideal soil are enclosed in a rectangular glass chamber model. A TV camera associated with a microscope was used to record the processes of capillary rise and drainage. It is clearly shown during capillary rise that the fluid exhibits a "jump" behavior at the neck of the pores in an initially dry profile or at the bottom of the water film in an initially wet profile. Under an initially dry condition, the jump initiates at the particle with smallest diameter. The jump process continues to higher elevations until at equilibrium the surface tensile force is balanced by the hydrostatic force. The wetting front at that time is readily observed as flat and saturated. Under an initially wet condition, capillary rise occurs as a water film thickening process associated with the jump process. Trapped air behind the wetting front renders the wetting front irregular and unsaturated. The capillary rise into an initially wet porous medium can be higher than that into an initially dry profile. During the drying process, large surface areas associated with the gas-liquid interface develop, allowing the porous medium to retain more water than during the wetting process at the same pressure. That mechanism explains better the hysteresis phenomenon in porous media in contrast to other mechanisms that now prevail.

  9. Three-Dimensional Numerical Modeling of Acoustic Trapping in Glass Capillaries

    DEFF Research Database (Denmark)

    Ley, Mikkel Wennemoes Hvitfeld; Bruus, Henrik

    2017-01-01

    Acoustic traps are used to capture and handle suspended microparticles and cells in microfluidic applications. A particular simple and much-used acoustic trap consists of a commercially available, millimeter-sized, liquid-filled straight glass capillary actuated by a piezoelectric transducer. Here......, we present a three-dimensional numerical model of the acoustic pressure field in the liquid coupled to the displacement field of the glass wall, taking into account mixed standing and traveling waves as well as absorption. The model explains the dynamical mechanism that leads to the formation...

  10. Multi-Capillary Column-Ion Mobility Spectrometry of Volatile Metabolites Emitted by Saccharomyces Cerevisiae

    Directory of Open Access Journals (Sweden)

    Christoph Halbfeld

    2014-09-01

    Full Text Available Volatile organic compounds (VOCs produced during microbial fermentations determine the flavor of fermented food and are of interest for the production of fragrances or food additives. However, the microbial synthesis of these compounds from simple carbon sources has not been well investigated so far. Here, we analyzed the headspace over glucose minimal salt medium cultures of Saccharomyces cerevisiae using multi-capillary column-ion mobility spectrometry (MCC-IMS. The high sensitivity and fast data acquisition of the MCC-IMS enabled online analysis of the fermentation off-gas and 19 specific signals were determined. To four of these volatile compounds, we could assign the metabolites ethanol, 2-pentanone, isobutyric acid, and 2,3-hexanedione by MCC-IMS measurements of pure standards and cross validation with thermal desorption–gas chromatography-mass spectrometry measurements. Despite the huge biochemical knowledge of the biochemistry of the model organism S. cerevisiae, only the biosynthetic pathways for ethanol and isobutyric acid are fully understood, demonstrating the considerable lack of research of volatile metabolites. As monitoring of VOCs produced during microbial fermentations can give valuable insight into the metabolic state of the organism, fast and non-invasive MCC-IMS analyses provide valuable data for process control.

  11. Temperature-assisted On-column Solute Focusing: A General Method to Reduce Pre-column Dispersion in Capillary High Performance Liquid Chromatography

    Science.gov (United States)

    Groskreutz, Stephen R.; Weber, Stephen G.

    2014-01-01

    Solvent-based on-column focusing is a powerful and well known approach for reducingthe impact of pre-column dispersion in liquid chromatography. Here we describe an orthogonal temperature-based approach to focusing called temperature-assisted on-column solute focusing (TASF). TASF is founded on the same principles as the more commonly used solvent-based method wherein transient conditions are created thatlead to high solute retention at the column inlet. Combining the low thermal mass of capillary columns and the temperature dependence of solute retentionTASF is used effectivelyto compress injection bands at the head of the column through the transient reduction in column temperature to 5 °C for a defined 7 mm segment of a 6 cm long 150 μm I.D. column. Following the 30 second focusing time, the column temperature is increased rapidly to the separation temperature of 60 °C releasing the focused band of analytes. We developed a model tosimulate TASF separations based on solute retention enthalpies, focusing temperature, focusing time, and column parameters. This model guides the systematic study of the influence of sample injection volume on column performance.All samples have solvent compositions matching the mobile phase. Over the 45 to 1050 nL injection volume range evaluated, TASF reducesthe peak width for all soluteswith k’ greater than or equal to 2.5, relative to controls. Peak widths resulting from injection volumes up to 1.3 times the column fluid volume with TASF are less than 5% larger than peak widths from a 45 nL injection without TASF (0.07 times the column liquid volume). The TASF approach reduced concentration detection limits by a factor of 12.5 relative to a small volume injection for low concentration samples. TASF is orthogonal to the solvent focusing method. Thus, it canbe used where on-column focusing is required, but where implementation of solvent-based focusing is difficult. PMID:24973805

  12. Voltage-assisted capillary LC of peptides using monolithic capillary columns prepared by ring-opening metathesis polymerization

    Czech Academy of Sciences Publication Activity Database

    Sedláková, Pavla; Mikšík, Ivan; Gatschelhofer, Ch.; Sinner, F. M.; Buchmeiser, M. R.

    2007-01-01

    Roč. 28, č. 13 (2007), s. 2219-2222 ISSN 0173-0835 R&D Projects: GA ČR GA203/05/2539; GA ČR GA203/06/1044; GA MŠk(CZ) 1M0510 Institutional research plan: CEZ:AV0Z50110509 Keywords : ROMP * voltage-assisted capillary LC Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.609, year: 2007

  13. Study of tapered glass capillary focusing MeV ion beam

    International Nuclear Information System (INIS)

    Gong Zhiyu; Yan Sha; Ma Hongji; Nie Rui; Xue Jianming; Wang Yugang

    2012-01-01

    In recent years, tapered glass capillary ion beam focusing is developing rapidly. It is attractive for simple, compact, low cost and easy use. However, the focusing mechanism for MeV ion beams is still indistinct. We present several experimental results of focusing 2 MeV He + beam. Ion beams were focused by tapered glass capillaries with various outlet inner diameters from several micron to hundred micron. The current densities, angle divergences and energy spectra of the transmitted ion beams are measured. The results proved that 2 MeV He + ions can focused and guided by our capillaries. The energy spectra show that a great part of transmitted ions experienced obvious energy loss, which is different from results of others research groups. We discussed the reason and charged it to the larger incident angle. Considered the incident ions with larger incident angle, the charge will distribute in a layer of micro meter depth in the capillary’s inner wall, but not the surface. The energy loss and many other spectra characters can be explained in this way.

  14. Ellipsoidal and parabolic glass capillaries as condensers for x-ray microscopes

    International Nuclear Information System (INIS)

    Zeng Xianghui; Duewer, Fred; Feser, Michael; Huang, Carson; Lyon, Alan; Tkachuk, Andrei; Yun Wenbing

    2008-01-01

    Single-bounce ellipsoidal and paraboloidal glass capillary focusing optics have been fabricated for use as condenser lenses for both synchrotron and tabletop x-ray microscopes in the x-ray energy range of 2.5-18 keV. The condenser numerical apertures (NAs) of these devices are designed to match the NA of x-ray zone plate objectives, which gives them a great advantage over zone plate condensers in laboratory microscopes. The fabricated condensers have slope errors as low as 20 μrad rms. These capillaries provide a uniform hollow-cone illumination with almost full focusing efficiency, which is much higher than what is available with zone plate condensers. Sub-50 nm resolution at 8 keV x-ray energy was achieved by utilizing this high-efficiency condenser in a laboratory microscope based on a rotating anode generator

  15. Experimental results from a large volume active target made of glass capillaries and liquid scintillator

    International Nuclear Information System (INIS)

    Annis, P.; Buontempo, S.; Brunner, J.; De Jong, M.; Fabre, J.P.; Frenkel, A.; Galeazzi, F.; Golovkin, S.; Gregoire, G.; Hoepfner, K.; Konijn, J.; Kozarenko, E.; Kreslo, I.; Kushnirenko, A.; Martellotti, G.; Mazzoni, M.A.; Medvedkov, A.; Michel, L.; Mondardini, M.R.; Panman, J.; Penso, G.; Petukhov, Y.; Riccardi, F.; Siegmund, W.P.; Strack, R.; Tyukov, V.; Vasilchenko, V.; Vilain, P.; Wilquet, G.; Winter, K.; Wong, H.; Zymin, K.

    1995-01-01

    We are investigating the feasibility of high-resolution tracking with an active target made of glass capillaries filled with organic liquid scintillator. This technique allows real time detection of short-lived particle decays. In this paper, we report on experimental results obtained from an active target having 2 x 2 cm 2 cross section and 180 cm length, installed in front of the CHORUS detector and exposed to the CERN Wide Band Neutrino Beam. The detector consists of 5.1 x 10 5 capillaries with 20 μm inner diameter, read out by a single optoelectronic chain and a Megapixel CCD. Details on tests in the neutrino beam will be reported. First neutrino interactions have been detected. (orig.)

  16. Capillary Columns with a Sorbent Based on Functionalized Poly(1-Trimethylsilyl-1-Propyne) for the Elution Analysis of Natural Gas

    Science.gov (United States)

    Yakovleva, E. Yu.; Patrushev, Yu. V.; Pai, Z. P.

    2018-05-01

    The chromatographic properties of capillary columns prepared using functionalized poly(1- trimethylsilyl-1-propyne) (PTMSP) are evaluated and compared with the performance of a commercial column with divinylbenzene polymer sorbent. The loading capacity of a PTMSP column with dimensions of 30 m × 0.53 mm × 0.8 μm is shown to be about 2.5 times higher than that of a divinylbenzene polymer column with a diameter of 0.32 mm and a film thickness of 10 μm. The increased value of the background current for PTMSP columns at 220°C is explained by the presence of non-polar bulky substituents in the polymer chain. Differences in the order of elution are found for the following pairs of compounds: acetylene-ethylene; ethane-water; butene-1-isobutane; and sulfur dioxide-carbonyl sulfide. On a column with the functionalized PTMC, analysis of a mixture composition close to natural gas is found to be complete within 27 min.

  17. Hysteresis critical point of nitrogen in porous glass: occurrence of sample spanning transition in capillary condensation.

    Science.gov (United States)

    Morishige, Kunimitsu

    2009-06-02

    To examine the mechanisms for capillary condensation and for capillary evaporation in porous glass, we measured the hysteresis critical points and desorption scanning curves of nitrogen in four kinds of porous glasses with different pore sizes (Vycor, CPG75A, CPG120A, and CPG170A). The shapes of the hysteresis loop in the adsorption isotherm of nitrogen for the Vycor and the CPG75A changed with temperature, whereas those for the CPG120A and the CPG170A remained almost unchanged with temperature. The hysteresis critical points for the Vycor and the CPG75A fell on the common line observed previously for ordered mesoporous silicas. On the other hand, the hysteresis critical points for the CPG120A and the CPG170A deviated appreciably from the common line. This strongly suggests that capillary evaporation of nitrogen in the interconnected and disordered pores of both the Vycor and the CPG75A follows a cavitation process at least in the vicinity of their hysteresis critical temperatures in the same way as that in the cagelike pores of the ordered silicas, whereas the hysteresis critical points in the CPG120A and the CPG170A have origin different from that in the cagelike pores. The desorption scanning curves for the CPG75A indicated the nonindependence of the porous domains. On the other hand, for both the CPG120A and the CPG170A, we obtained the scanning curves that are expected from the independent domain theory. All these results suggest that sample spanning transitions in capillary condensation and evaporation take place inside the interconnected pores of both the CPG120A and the CPG170A.

  18. Characteristics Of Dosimeter TL CaSO4:Dy Glass Capillaries For Environmental Radiation Dose Monitoring

    International Nuclear Information System (INIS)

    Sofyan Hasnel; Yulianti, Helfi; Ramain, Abubakar; Kusumawati, Dyah D.; Suyati

    2000-01-01

    research on the characteristic of dosimeter TL CaSO 4 : Dy glass capillaries for environmental dose radiation have been carried out. The results obtained are uniform response and reproducibility during three cycles consumption with average percentage standard deviation of 7.31 % and 5.45%. The response dose is linear and has a minimum detectable dose of 0.01 mGy, sunshine effect with non-penetrating light capsule of 4.65%, humidity effects is not significant by using non-penetrating light capsule. Radiation dose information during 30 days are fading 25%

  19. Glass capillary optics for making x-ray beams of 0.1 to 50 microns diameter

    International Nuclear Information System (INIS)

    Bilderback, Donald H.; Fontes, Ernest

    1997-01-01

    We have fabricated a unique computerized glass puller that can make parabolic or elliptically tapered glass capillaries for microbeam x-ray experiments from hollow glass tubing. We have produced optics that work in a single-bounce imaging mode or in a multi-bounce condensing mode. The imaging-mode capillaries have been used to create 20 to 50 micron diameter x-ray beams at 12 keV that are quite useful for imaging diffraction patterns from tiny bundles of carbon and Kevlar fibers. The condensing-mode capillaries are useful for creating submicron diameter beams and show great promise in x-ray fluorescence applications with femtogram sensitivity for patterned Er and Ti dopants diffused into an optically-active lithium niobate wafer

  20. Analysis of nitrites and nitrates in hams and sausages by open-tubular capillary electrochromatography with a nanolatex-coated capillary column.

    Science.gov (United States)

    Zhang, Yanhao; Tian, Xiangyu; Guo, Yaxiao; Li, Haibin; Yu, Ajuan; Deng, Zhifen; Sun, Barry Baoguo; Zhang, Shusheng

    2014-04-16

    In this work, a new open-tubular capillary electrochromatography (OT-CEC) method with the nanolatex-coated column was proposed for the determination of nitrites and nitrates in foodstuffs. The method was simple and repeatable as a result of avoiding the introduction of an electroosmotic flow reverse additive (such as cetyltrimethylammonium chloride) in electrophoretic buffer. The limits of quantitation were 0.89 and 1.05 mg kg⁻¹ for nitrate and nitrite, respectively, whereas the overall recoveries ranged from 94 to 103%. The developed OT-CEC method was successfully applied for 12 samples, and the residue profiles of nitrites and nitrates in hams and sausages were obtained and evaluated.

  1. Chiral separation of methoxamine and lobeline in capillary zone electrophoresis using ethylbenzene-deactivated fused-silica capillary columns and cyclodextrins as buffer additives.

    Science.gov (United States)

    Russo, M V

    2002-08-01

    The complete chiral separation of methoxamine and lobeline was achieved by capillary zone electrophoresis on an ethylbenzene-deactivated fused-silica capillary column and with cyclodextrins (CDs) as buffer additives. Among the CDs investigated in this study, i.e. alpha-CD, beta-CD, dimethyl-beta-CD, hydroxypropyl-beta-CD and gamma-CD, all the three beta-type CDs showed chiral recognition on the two drugs investigated. Under the investigated conditions, the baseline chiral separation of methoxamine can be achieved with 90 mM Tris-H3PO4 (pH 2.5) containing 11.5 mM of the three beta-type CDs, with dimethyl-beta-CD giving the best resolution, whereas the baseline chiral separation of lobeline can be realized by using 90 mM Tris-H3PO4 buffer (pH 2.5) containing 5.8 mM dimethyl-beta-CD or 29.5 mM hydroxypropyl-beta-CD.

  2. New method for evaluating irreversible adsorption and stationary phase bleed in gas chromatographic capillary columns.

    Science.gov (United States)

    Wright, Bob W; Wright, Cherylyn W

    2012-10-26

    A novel method is described for the evaluation of irreversible adsorption and column bleed in gas chromatographic (GC) columns using a tandem GC approach. This work specifically determined the degree of irreversible adsorption behavior of specific sulfur and phosphorous containing test probe compounds at levels ranging from approximately 50 picograms (pg) to 1 nanogram (ng) on selected gas chromatographic columns. This method does not replace existing evaluation methods that characterize reversible adsorption but provides an additional tool. The test compounds were selected due to their ease of adsorption and their importance in the specific trace analytical detection methodology being developed. Replicate chromatographic columns with 5% phenylmethylpolysiloxane (PMS), polyethylene glycol (wax), trifluoropropylpolysiloxane (TFP), or 78% cyanopropylpolysiloxane stationary phases from a variety of vendors were evaluated. As expected, the results demonstrate that the different chromatographic phases exhibit differing degrees of irreversible adsorption behavior. The results also indicate that all manufacturers do not produce equally inert columns nor are columns from a given manufacturer identical. The wax-coated columns for the test probes used were more inert as a group than 5% PMS coated columns, and they were more reproducibly manufactured. Both TFP and 78% cyanopropylpolysiloxane columns displayed superior inertness to the test compounds compared to either 5% PMS- or wax-coated columns. Irreversible adsorption behavior was characterized for a limited range of stationary phase film thicknesses. In addition, the method was shown effective for characterizing column bleed and methods to remove bleed components. This method is useful in screening columns for demanding applications and to obtain diagnostic information related to improved preparation methods. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Temperature-based on-column solute focusing in capillary liquid chromatography reduces peak broadening from pre-column dispersion and volume overload when used alone or with solvent-based focusing.

    Science.gov (United States)

    Groskreutz, Stephen R; Horner, Anthony R; Weber, Stephen G

    2015-07-31

    On-column focusing is essential for satisfactory performance using capillary scale columns. On-column focusing results from generating transient conditions at the head of the column that lead to high solute retention. Solvent-based on-column focusing is a well-known approach to achieve this. Temperature-assisted on-column focusing (TASF) can also be effective. TASF improves focusing by cooling a short segment of the column inlet to a temperature that is lower than the column temperature during the injection and then rapidly heating the focusing segment to the match the column temperature. A troublesome feature of an earlier implementation of TASF was the need to leave the capillary column unpacked in that portion of the column inside the fitting connecting it to the injection valve. We have overcome that problem in this work by packing the head of the column with solid silica spheres. In addition, technical improvements to the TASF instrumentation include: selection of a more powerful thermo-electric cooler to create faster temperature changes and electronic control for easy incorporation into conventional capillary instruments. Used in conjunction with solvent-based focusing and with isocratic elution, volumes of paraben samples (esters of p-hydroxybenzoic acid) up to 4.5-times the column liquid volume can be injected without significant bandspreading due to volume overload. Interestingly, the shapes of the peaks from the lowest volume injections that we can make, 30nL, are improved when using TASF. TASF is very effective at reducing the detrimental effects of pre-column dispersion using isocratic elution. Finally, we show that TASF can be used to focus the neuropeptide galanin in a sample solvent with elution strength stronger than the mobile phase. Here, the stronger solvent is necessitated by the need to prevent peptide adsorption prior to and during analysis. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Gas-chromatographic separation of hydrogen isotopes mixtures on capillary molecular sieve 5 A column at 173 K

    International Nuclear Information System (INIS)

    Bidica, N.; Preda, A.; Stanciu, V.

    2002-01-01

    Analysis of a gas mixture of hydrogen species, is not too easy because the differences in their physical-chemical properties are very small; the most different are their masses, and consequently most common analytical method appear to be the mass-spectrometry. However, the impossibility to distinguish between two ions (atomic or molecular) with the same mass renders this method as unapplicable. Another problem is the decay of tritium with production of 3 He. These disadvantages of mass-spectrometry have made that other analytical methods, like gas chromatography, to be considered and developed. Thus, there are many papers about various chromatographic columns especially prepared for hydrogen species separation but the preparation and treatment of these columns are very difficult to reproduce. Besides these, there are two other main disadvantages: column operating temperature is very low and long retention times for hydrogen species (more than half an hour) are required. However, the gas-chromatography method still remains an appropriate one. The method described in this paper was based on using a capillary molecular sieve 5A column which has been operated for this kind of separation. The retention times were relatively short, about 8-9 minutes. The carrier gas was Ne and the detector - TCD. In the paper chromatograms for various carrier flow rates and various hydrogen isotope mixtures are presented. The results demonstrated a quite good efficiency for H 2 , HD, D 2 and a not very good one for orthoH 2 -paraH 2 . (authors)

  5. Capillary electrophoresis in an extended nanospray tip-electrospray as an electrophoretic column

    Czech Academy of Sciences Publication Activity Database

    Týčová, Anna; Foret, František

    2015-01-01

    Roč. 1388, APR (2015), s. 274-279 ISSN 0021-9673 R&D Projects: GA ČR(CZ) GBP206/12/G014 Institutional support: RVO:68081715 Keywords : mass spectrometry * interface * separation * capillary electrophoresis Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.926, year: 2015

  6. Fast preparation of hybrid monolithic columns via photo-initiated thiol-yne polymerization for capillary liquid chromatography.

    Science.gov (United States)

    Ma, Shujuan; Zhang, Haiyang; Li, Ya; Li, Yanan; Zhang, Na; Ou, Junjie; Ye, Mingliang; Wei, Yinmao

    2018-02-23

    Although several approaches have been developed to fabricate hybrid monoliths, it would still take a few hours to finish the formation of monoliths. Herein, photo-initiated thiol-yne polymerization was first adopted to in situ fabricate hybrid monoliths within the confines of UV-transparent fused-silica capillary. A silicon-containing diyne (1,3-diethynyltetramethyl-disiloxane, DYDS) was copolymerized with three multithiols, 1,6-hexanedithiol, trimethylolpropane tris(3-mercaptopropionate) and pentaerythriol tetrakis(3-mercaptopropionate), by using a binary porogenic system of diethylene glycol diethyl ether (DEGDE)/poly(ethylene glycol) (PEG200) within 10 min. Several characterizations of three hybrid monoliths (assigned as I, II and III, respectively) were performed. The results showed that these hybrid monoliths possessed bicontinuous porous structure, which was remarkably different from that via typical free-radical polymerization. The highest column efficiency of 76,000 plates per meter for butylbenzene was obtained on the column I in reversed-phase liquid chromatography (RPLC). It was observed that the efficiencies for strong-retained butylbenzene were almost close to those of weak-retained benzene, indicating a retention-independent efficient performance of small molecules on hybrid column I. The surface area of this hybrid monolith was very small in the dry state (less than 10.0 m 2 /g), and the chromatographic behavior of hybrid monolithic columns would be possibly explained by radical-mediated step-growth process of thiol-yne polymerization. Finally, the column I was applied for separation of BSA tryptic digest by cLC-MS/MS, indicating satisfactory separation ability for complicated samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Photodeposited silver nanoparticles for on-column surface-enhanced Raman spectrometry detection in capillary electrophoresis

    Czech Academy of Sciences Publication Activity Database

    Přikryl, Jan; Klepárník, Karel; Foret, František

    2012-01-01

    Roč. 1226, - (2012), s. 43-47 ISSN 0021-9673 R&D Projects: GA ČR GA203/08/1680; GA ČR(CZ) GAP301/11/2055; GA MŠk LC06023 Institutional research plan: CEZ:AV0Z40310501 Keywords : SERS * capillary electrophoresis * photodeposition Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.612, year: 2012

  8. Stripe-like Clay Nanotubes Patterns in Glass Capillary Tubes for Capture of Tumor Cells.

    Science.gov (United States)

    Liu, Mingxian; He, Rui; Yang, Jing; Zhao, Wei; Zhou, Changren

    2016-03-01

    Here, we used capillary tubes to evaporate an aqueous dispersion of halloysite nanotubes (HNTs) in a controlled manner to prepare a patterned surface with ordered alignment of the nanotubes . Sodium polystyrenesulfonate (PSS) was added to improve the surface charges of the tubes. An increased negative charge of HNTs is realized by PSS coating (from -26.1 mV to -52.2 mV). When the HNTs aqueous dispersion concentration is higher than 10%, liquid crystal phenomenon of the dispersion is found. A typical shear flow behavior and decreased viscosity upon shear is found when HNTs dispersions with concentrations higher than 10%. Upon drying the HNTs aqueous dispersion in capillary tubes, a regular pattern is formed in the wall of the tube. The width and spacing of the bands increase with HNTs dispersion concentration and decrease with the drying temperature for a given initial concentration. Morphology results show that an ordered alignment of HNTs is found especially for the sample of 10%. The patterned surface can be used as a model for preparing PDMS molding with regular micro-/nanostructure. Also, the HNTs rough surfaces can provide much higher tumor cell capture efficiency compared to blank glass surfaces. The HNTs ordered surfaces provide promising application for biomedical areas such as biosensors.

  9. Characterisation of capillary ionic liquid columns for gas chromatography-mass spectrometry analysis of fatty acid methyl esters.

    Science.gov (United States)

    Zeng, Annie Xu; Chin, Sung-Tong; Nolvachai, Yada; Kulsing, Chadin; Sidisky, Leonard M; Marriott, Philip J

    2013-11-25

    Due to their distinct chemical properties, the application of ionic liquid (IL) compounds as gas chromatography (GC) stationary phases offer unique GC separation especially in the analysis of geometric and positional fatty acid methyl ester (FAME) isomers. Elution behaviour of FAME on several commercialised IL capillary columns including phosphonium based SLB-IL59, SLB-IL60, SLB-IL61 and SLB-IL76 and imidazolium based SLB-IL82, SLB-IL100, and SLB-IL111 as well as a general purpose column SLB-5ms, were evaluated in gas chromatography-mass spectrometry (GC-MS) analysis. The phases were further characterised by using a linear solvation energy relationship (LSER) approach according to the equivalent chain length (ECL) index of FAME. Among all tested IL columns, elution temperatures of saturated FAME increased as their McReynolds' polarity value decreased, except for IL60. ECL values increased markedly as the stationary phase polarity increased, particularly for the polyunsaturated FAME. The LSER study indicated a lowest l/e value at 0.864 for IL111, displaying phase selectivity towards unsaturated FAME, with higher peak capacity within a carbon number isomer group. s and e descriptors calculated from LSER were validated by excellent correlation with dipole moments and lowest unoccupied molecular orbital (LUMO) energies, with R(2) values of 0.99 and 0.92 respectively, calculated using GAUSSIAN. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Chromatographic efficiency of polar capillary columns applied for the analysis of fatty acid methyl esters by gas chromatography.

    Science.gov (United States)

    Waktola, Habtewold D; Mjøs, Svein A

    2018-04-01

    The chromatographic efficiency that could be achieved in temperature-programmed gas chromatography was compared for four capillary columns that are typically applied for analysis of fatty acid methyl esters (FAME). Three different carrier gases, hydrogen, helium and nitrogen, were applied. For each experiment, the carrier gas velocities and the temperature rates were varied with a full 9 × 3 design, with nine levels on the carrier gas velocity and temperature rates of 1, 2 or 3°C/min. Response surface methodology was used to create models of chromatographic efficiency as a function of temperature rate and carrier gas velocity. The chromatographic efficiency was defined as the inverse of peak widths measured in retention index units. The final results were standardized so that the efficiencies that could be achieved within a certain time frame, defined by the retention time of the last compound in the chromatogram, could be compared. The results show that there were clear differences in the efficiencies that could be achieved with the different columns and that the efficiency decreased with increasing polarity of the stationary phase. The differences can be explained by higher resistance to mass transfer in the stationary phase in the most polar columns. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. [Analysis of hydrogen isotopes by gas chromatography using a MnCl2 coated γ-Al2O3 capillary packed column].

    Science.gov (United States)

    Chen, Ping; Fu, Xiaolong; Hu, Peng; Xiao, Chengjian; Ren, Xingbi; Xia, Xiulong; Wang, Heyi

    2017-07-08

    The conventional packed column gas chromatographic analysis of hydrogen isotopes has low column efficiency, broad peak and long retention time. In this work, a γ -Al 2 O 3 with MnCl 2 coated capillary packed column was tested at cryogenic temperature. The systematic column efficiency analysis and the hydrogen isotopes analytical technique research had been carried out. The results showed that, the γ -Al 2 O 3 with MnCl 2 coating could greatly improve the surface degree of order, pore structure and adsorption properties. Also the o -H 2 peak and p -H 2 peak were eluted in a single area. The γ -Al 2 O 3 with MnCl 2 coating was packed into a 0.53 mm inner diameter and 1.0 m long fused silica capillary column. It had a good linear relationship used this column with thermal conductivity detector (TCD) to detect the volume concentrations of hydrogen isotopes from 1 to 10 mL/L, and the relative error was less than 5% for low concentration sample testing. For H 2 , HD and D 2 , the retention times can be shortened to 39, 46 and 60 s, respectively. The limits of detection were reduced to 0.046, 0.067 and 0.072 mL/L, respectively. Compared with conventional packed column, capillary packed column had sharper peak form, higher separation degree of adjacent components, shorter retention time and lower detection limits. The above results indicate that the capillary packed column with TCD detector can be used for fast detection of low concentration of hydrogen isotopes and their online analysis.

  12. Development of a positive column pulsed capillary discharge source for use with high resolution Fourier transform spectrometer

    International Nuclear Information System (INIS)

    Syed, W A A

    2002-01-01

    We report the designing and application of a positive column pulsed capillary discharge with the Fourier transform spectrometer (FTS). The pulsed light source has been used for the first time with the ultraviolet FTS. The experiment has been carried out with the high energy pulsed discharge with energy of 2-3 J lasting about 300 ns. A system has been developed to trigger the discharge at about 600 Hz with the pulses directly taken from the FTS sampling system. The spectrum of Ar III has been recorded in the 19 000-50 000 cm -1 region with good signal to noise ratio. The results have opened a wide range of applications in spectroscopy of multiply ionized species

  13. Simultaneous determination of metoprolol and metabolites in urine by capillary column gas chromatography as oxazolidineone and trimethylsilyl derivatives.

    Science.gov (United States)

    Gyllenhaal, O; Hoffmann, K J

    1984-08-10

    A method for the determination of metoprolol and its main metabolites in urine is presented. The method comprises derivatization of the aminopropanol side-chain with phosgene at alkaline pH and isolation in an organic phase at acidic pH. After trimethylsilylation, separation and quantification are performed by capillary column gas chromatography with flame ionization detection. The reaction is performed at pH 12 with 60 microliters of 2 M phosgene in toluene added in three portions. Diethyl ether--dichloromethane is used as extraction medium and bis(trimethylsilyl) acetamide as silylating agent. With spiked samples linear standard curves were obtained for metoprolol and three of its main metabolites with a detection limit varying between 4 and 20 mumol/l of urine. The method was applied to urine samples from a normal individual who had taken 292 mumol of metoprolol as tartrate.

  14. Chromatographic selectivity of poly(alkyl methacrylate-co-divinylbenzene) monolithic columns for polar aromatic compounds by pressure-driven capillary liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Shu-Ling; Wang, Chih-Chieh; Fuh, Ming-Ren, E-mail: msfuh@scu.edu.tw

    2016-10-05

    In this study, divinylbenzene (DVB) was used as the cross-linker to prepare alkyl methacrylate (AlMA) monoliths for incorporating π-π interactions between the aromatic analytes and AlMA-DVB monolithic stationary phases in capillary LC analysis. Various AlMA/DVB ratios were investigated to prepare a series of 30% AlMA-DVB monolithic stationary phases in fused-silica capillaries (250-μm i.d.). The physical properties (such as porosity, permeability, and column efficiency) of the synthesized AlMA-DVB monolithic columns were investigated for characterization. Isocratic elution of phenol derivatives was first employed to evaluate the suitability of the prepared AlMA-DVB columns for small molecule separation. The run-to-run (0.16–1.20%, RSD; n = 3) and column-to-column (0.26–2.95%, RSD; n = 3) repeatabilities on retention times were also examined using the selected AlMA-DVB monolithic columns. The π-π interactions between the aromatic ring and the DVB-based stationary phase offered better recognition on polar analytes with aromatic moieties, which resulted in better separation resolution of aromatic analytes on the AlMA-DVB monolithic columns. In order to demonstrate the capability of potential environmental and/or food safety applications, eight phenylurea herbicides with single benzene ring and seven sulfonamide antibiotics with polyaromatic moieties were analyzed using the selected AlMA-DVB monolithic columns. - Highlights: • First investigation on chromatographic selectivity of AlMA-DVB monolithic columns. • Good run-to-run/column-to-column repeatability (<3%) on AlMA-DVB monolithic columns. • Efficient separation of phenylurea herbicides and sulfonamides on AlMA-DVB columns.

  15. Controllable Shrinking of Glass Capillary Nanopores Down to sub-10 nm by Wet-Chemical Silanization for Signal-Enhanced DNA Translocation.

    Science.gov (United States)

    Xu, Xiaolong; Li, Chuanping; Zhou, Ya; Jin, Yongdong

    2017-10-27

    Diameter is a major concern for nanopore based sensing. However, directly pulling glass capillary nanopore with diameter down to sub-10 nm is very difficult. So, post treatment is sometimes necessary. Herein, we demonstrate a facile and effective wet-chemical method to shrink the diameter of glass capillary nanopore from several tens of nanometers to sub-10 nm by disodium silicate hydrolysis. Its benefits for DNA translocation are investigated. The shrinking of glass capillary nanopore not only slows down DNA translocation, but also enhances DNA translocation signal and signal-to-noise ratio significantly (102.9 for 6.4 nm glass nanopore, superior than 15 for a 3 nm silicon nitride nanopore). It also affects DNA translocation behaviors, making the approach and glass capillary nanopore platform promising for DNA translocation studies.

  16. Monolithic poly(1,2-bis(p-vinylphenyl)ethane) capillary columns for simultaneous separation of low- and high-molecular-weight compounds.

    Science.gov (United States)

    Greiderer, Andreas; Ligon, S Clark; Huck, Christian W; Bonn, Günther K

    2009-08-01

    Monolithic poly(1,2-bis(p-vinylphenyl)ethane (BVPE)) capillary columns were prepared by thermally initiated free radical polymerisation of 1,2-bis(p-vinylphenyl)ethane in the presence of inert diluents (porogens) and alpha,alpha'-azoisobutyronitrile (AIBN) as initiator. Polymerisations were accomplished in 200 microm ID fused silica capillaries at 65 degrees C and for 60 min. Mercury intrusion porosimetry measurements of the polymeric RP support showed a broad bimodal pore-size-distribution of mesopores and small macropores in the range of 5-400 nm and flow-channels in the mum range. N(2)-adsorption (BET) analysis resulted in a tremendous enhancement of surface area (101 m(2)/g) of BVPE stationary phases compared to typical organic monoliths (approximately 20 m(2)/g), indicating the presence of a considerable amount of mesopores. Consequently, the adequate proportion of both meso- and (small) macropores allowed the rapid and high-resolution separation of low-molecular-weight compounds as well as biomolecules on the same monolithic support. At the same time, the high fraction of flow-channels provided enhanced column permeability. The chromatographic performance of poly(1,2-bis(p-vinylphenyl)ethane) capillary columns for the separation of biomolecules (proteins, oligonucleotides) and small molecules (alkyl benzenes, phenols, phenons) are demonstrated in this article. Additionally, pressure drop versus flow rate measurements of novel poly(1,2-bis(p-vinylphenyl)ethane) capillary columns confirmed high mechanical robustness, low swelling in organic solvents and high permeability. Due to the simplicity of monolith fabrication, comprehensive studies of the retention and separation behaviour of monolithic BVPE columns resulted in high run-to-run and batch-to-batch reproducibilities. All these attributes prove the excellent applicability of monolithic poly(1,2-bis(p-vinylphenyl)ethane) capillary columns for micro-HPLC towards a huge range of analytes of different

  17. Bridged polysilsesquioxane-based wide-bore monolithic capillary columns for hydrophilic interaction chromatography

    Czech Academy of Sciences Publication Activity Database

    Šesták, Jozef; Moravcová, Dana; Křenková, Jana; Planeta, Josef; Roth, Michal; Foret, František

    2017-01-01

    Roč. 1479, JAN (2017), s. 204-209 ISSN 0021-9673 R&D Projects: GA ČR(CZ) GA14-06319S; GA ČR(CZ) GA16-03749S Institutional support: RVO:68081715 Keywords : silica monolithic column * HILIC * oligosaccharides * nucleosides Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 3.981, year: 2016

  18. Zwitterionic silica-based monolithic capillary columns for isocratic and gradient hydrophilic interaction liquid chromatography

    Czech Academy of Sciences Publication Activity Database

    Moravcová, Dana; Planeta, Josef; Kahle, Vladislav; Roth, Michal

    2012-01-01

    Roč. 1270, DEC 28 (2012), s. 178-185 ISSN 0021-9673 R&D Projects: GA MV VG20112015021; GA ČR(CZ) GAP206/11/0138; GA ČR(CZ) GAP106/12/0522 Institutional support: RVO:68081715 Keywords : HILIC * Monolithic silica column * Nucleoside separation * Nucleic acid base Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.612, year: 2012

  19. Preparation and evaluation of open-tubular capillary column combining a metal-organic framework and a brush-shaped polymer for liquid chromatography.

    Science.gov (United States)

    Chen, Kai; Zhang, Lingyi; Zhang, Weibing

    2018-03-30

    In this work, an open-tubular capillary liquid-phase column was prepared by modifying chain polymer on the inner surface of capillary and chemical bonding of metal organic frameworks, NH 2 -UiO-66, to the brushes of chain polymer (poly(glycidyl methacrylate)). Besides advantages of facial preparation and good permeability, the chain polymer effectively increases the modification amount of NH 2 -UiO-66 nanoparticles to increase the phase ratio of open-tubular capillary column and enhance the interactions with analytes. The results of scanning electron microscope energy-dispersive X-ray spectra indicated that NH 2 -UiO-66 nanoparticles were successfully bonded to the chain polymer. Because of the hydrophobic interaction and hydrogen bonding interaction between the analytes and the ligand of NH 2 -UiO-66, different analytes were well separated on the NH 2 -UiO-66-modified poly(glycidyl methacrylate) capillary (1.12 m × 25 μm id × 365 μm od) with the high absolute column efficiency reaching 121 477 plates, benefiting from an open-tubular column and low mass transfer resistance provided by polymer brush and metal-organic framework crystal. The relative standard deviations of the retention time for run-to-run, day-to-day, and column-to-column (n = 3) runs are below 4.28%, exhibiting good repeatability. Finally, the column was successfully applied to separation of flavonoids in licorice. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Preparation and characterization of micro-cell membrane chromatographic column with N-hydroxysuccinimide group-modified silica-based porous layer open tubular capillary.

    Science.gov (United States)

    Xu, Liang; Xu, Bei; Zhao, Zhi-Yu; Yang, Hui-Ping; Tang, Cheng; Dong, Lin-Yi; Liu, Kun; Fu, Li; Wang, Xian-Hua

    2017-09-22

    Cell membrane chromatography (CMC) is an effective tool in screening active compounds from natural products and studying membrane protein interactions. Nevertheless, it always consumes a large amount of cells (e.g. 10 7 -10 8 ) for column preparation. To overcome this, micro-CMC (mCMC), that employs a silica capillary as membrane carrier, was developed. However, both CMC and mCMC suffer from short column life span (e.g. 3days), mainly due to the falling-off of cellular membranes (CMs). This has greatly limited further application of CMC and mCMC, especially when the cells are hard to obtain. To solve this, N-hydroxysuccinimide (NHS)-modified silica-based porous layer open tubular capillary was first prepared for mCMC. The NHS groups can easily react with amino groups on CMs to form a stable covalent bond under a mild condition. So, CMs immobilized on the NHS-modified capillary are less likely to fall off. To verify this, SKBR3/mCMC (Her2 positive) and BALL1/mCMC (CD20 positive) columns were prepared. Two monoclonal antibody drugs, trastuzumab (anti-Her2) and rituximab (anti-CD20), were selected as analytes to characterize the columns. As a result, NHS-modified column for mCMC can afford higher chromatographic retention than non-modified column. Besides, the column life span was significantly improved to more than 16days for SKBR3/mCMC and 14days for BALL1/mCMC, while the compared column showed a sharp decline in retention factor in first 3days. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. A glass capillary based microfluidic electromembrane extraction of basic degradation products of nitrogen mustard and VX from water.

    Science.gov (United States)

    Tak, Vijay; Kabra, Ankur; Pardasani, Deepak; Goud, D Raghavender; Jain, Rajeev; Dubey, D K

    2015-12-24

    In this work, a glass capillary based microfluidic electromembrane extraction (μ-EME) was demonstrated for the first time. The device was made by connecting an auxillary borosilicate glass tubing (O.D. 3mm, I.D. 2mm) perpendicular to main borosilicate glass capillary just below one end of the capillary (O.D. 8mm, I.D. 1.2mm). It generated the distorted T-shaped device with inlet '1' and inlet '2' for the introduction of sample and acceptor solutions, respectively. At one end of this device (inlet '2'), a microsyringe containing acceptor solution along with hollow fiber (O.D. 1000μm) was introduced. This configuration creates the micro-channel between inner wall of glass capillary and outer surface of hollow fiber. Sample solution was pumped into the system through another end of glass capillary (inlet '1'), with a micro-syringe pump. The sample was in direct contact with the supported liquid membrane (SLM), consisted of 20% (w/w) di-(2-ethylhexyl)phosphate in 2-nitrophenyl octyl ether immobilized in the pores of the hollow fiber. In the lumen of the hollow fiber, the acceptor phase was present. The driving force for extraction was direct current (DC) electrical potential sustained over the SLM. Highly polar (logP=-2.5 to 1.4) basic degradation products of nitrogen mustard and VX were selected as model analytes. The influence of chemical composition of SLM, extraction time, voltage and pH of donor and acceptor phase were investigated. The model analytes were extracted from 10μL of pure water with recoveries ranging from 15.7 to 99.7% just after 3min of operation time. Under optimized conditions, good limits of detection (2-50ngmL(-1)), linearity (from 5-1000 to 100-1000ngmL(-1)), and repeatability (RSDs below 11.9%, n=3) were achieved. Applicability of the proposed μ-EME was proved by recovering triethanolamine (31.3%) from 10μL of five times diluted original water sample provided by the Organization for the Prohibition of Chemical Weapons during 28th official

  2. Preparation and evaluation of poly(alkyl methacrylate-co-methacrylic acid-co-ethylene dimethacrylate) monolithic columns for separating polar small molecules by capillary liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Shu-Ling; Wu, Yu-Ru; Lin, Tzuen-Yeuan; Fuh, Ming-Ren, E-mail: msfuh@scu.edu.tw

    2015-04-29

    Highlights: • Methacrylic acid (MAA) was used to increase hydrophilicity of polymeric monoliths. • Fast separation of phenol derivatives was achieved in 5 min using MAA-incorporated column. • Separations of aflatoxins and phenicol antibiotics were achieved using MAA-incorporated column. - Abstract: In this study, methacrylic acid (MAA) was incorporated with alkyl methacrylates to increase the hydrophilicity of the synthesized ethylene dimethacrylate-based (EDMA-based) monoliths for separating polar small molecules by capillary LC analysis. Different alkyl methacrylate–MAA ratios were investigated to prepare a series of 30% alkyl methacrylate–MAA–EDMA monoliths in fused-silica capillaries (250-μm i.d.). The porosity, permeability, and column efficiency of the synthesized MAA-incorporated monolithic columns were characterized. A mixture of phenol derivatives is employed to evaluate the applicability of using the prepared monolithic columns for separating small molecules. Fast separation of six phenol derivatives was achieved in 5 min with gradient elution using the selected poly(lauryl methacrylate-co-MAA-co-EDMA) monolithic column. In addition, the effect of acetonitrile content in mobile phase on retention factor and plate height as well as the plate height-flow velocity curves were also investigated to further examine the performance of the selected poly(lauryl methacrylate-co-MAA-co-EDMA) monolithic column. Moreover, the applicability of prepared polymer-based monolithic column for potential food safety applications was also demonstrated by analyzing five aflatoxins and three phenicol antibiotics using the selected poly(lauryl methacrylate-co-MAA-co-EDMA) monolithic column.

  3. Analysis of multiple quaternary ammonium compounds in the brain using tandem capillary column separation and high resolution mass spectrometric detection.

    Science.gov (United States)

    Falasca, Sara; Petruzziello, Filomena; Kretz, Robert; Rainer, Gregor; Zhang, Xiaozhe

    2012-06-08

    Endogenous quaternary ammonium compounds are involved in various physiological processes in the central nervous system. In the present study, eleven quaternary ammonium compounds, including acetylcholine, choline, carnitine, acetylcarnitine and seven other acylcarnitines of low polarity, were analyzed from brain extracts using a two dimension capillary liquid chromatography-Fourier transform mass spectrometry method. To deal with their large difference in hydrophobicities, tandem coupling between reversed phase and hydrophilic interaction chromatography columns was used to separate all the targeted quaternary ammonium compounds. Using high accuracy mass spectrometry in selected ion monitoring mode, all the compounds could be detected from each brain sample with high selectivity. The developed method was applied for the relative quantification of these quaternary ammonium compounds in three different brain regions of tree shrews: prefrontal cortex, striatum, and hippocampus. The comparative analysis showed that quaternary ammonium compounds were differentially distributed across the three brain areas. The analytical method proved to be highly sensitive and reliable for simultaneous determination of all the targeted analytes from brain samples. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Multi-capillary column-ion mobility spectrometry: a potential screening system to differentiate virgin olive oils.

    Science.gov (United States)

    Garrido-Delgado, Rocío; Arce, Lourdes; Valcárcel, Miguel

    2012-01-01

    The potential of a headspace device coupled to multi-capillary column-ion mobility spectrometry has been studied as a screening system to differentiate virgin olive oils ("lampante," "virgin," and "extra virgin" olive oil). The last two types are virgin olive oil samples of very similar characteristics, which were very difficult to distinguish with the existing analytical method. The procedure involves the direct introduction of the virgin olive oil sample into a vial, headspace generation, and automatic injection of the volatiles into a gas chromatograph-ion mobility spectrometer. The data obtained after the analysis by duplicate of 98 samples of three different categories of virgin olive oils, were preprocessed and submitted to a detailed chemometric treatment to classify the virgin olive oil samples according to their sensory quality. The same virgin olive oil samples were also analyzed by an expert's panel to establish their category and use these data as reference values to check the potential of this new screening system. This comparison confirms the potential of the results presented here. The model was able to classify 97% of virgin olive oil samples in their corresponding group. Finally, the chemometric method was validated obtaining a percentage of prediction of 87%. These results provide promising perspectives for the use of ion mobility spectrometry to differentiate virgin olive oil samples according to their quality instead of using the classical analytical procedure.

  5. Molecularly imprinted coated graphene oxide solid-phase extraction monolithic capillary column for selective extraction and sensitive determination of phloxine B in coffee bean

    International Nuclear Information System (INIS)

    Zhai, Haiyun; Su, Zihao; Chen, Zuanguang; Liu, Zhenping; Yuan, Kaisong; Huang, Lu

    2015-01-01

    Highlights: • A new GO-MISPE monolithic capillary column was prepared. • The column showed ability of impurities removal and excellent selectivity. • Phloxine B existed in real sample was enriched more than 90 times. • The GO-MISPE column presented good recovery and high stability. • The method was prospered to analyze phloxine B and LOD achieved 0.3 ng g −1 . - Abstract: A method was developed to sensitively determine phloxine B in coffee bean by molecularly imprinted polymers (MIPs) coated graphene oxide (GO) solid-phase extraction (GO-MISPE) coupled with high-performance liquid chromatography and laser-induced fluorescence detection (HPLC–LIF). The GO-MISPE capillary monolithic column was prepared by water-bath in situ polymerization, using GO as supporting material, phloxine B, methacrylic acid (MAA), and ethylene dimethacrylate (EDMA) as template, functional monomer, and cross-linker, respectively. The properties of the homemade GO-MISPE capillary monolithic column, including capacity and specificity, were investigated under optimized conditions. The GO-MIPs were characterized by scanning electron microscopy (SEM) and Fourier transform-infrared spectroscopy (FT-IR). The mean recoveries of phloxine B in coffee bean ranged from 89.5% to 91.4% and the intra-day and inter-day relative standard deviation (RSD) values all ranged from 3.6% to 4.7%. Good linearity was obtained over 0.001–2.0 μg mL −1 (r = 0.9995) with the detection limit (S/N = 3) of 0.075 ng mL −1 . Under the selected conditions, enrichment factors of over 90-fold were obtained and extraction on the monolithic column effectively cleaned up the coffee bean matrix. The results demonstrated that the proposed GO-MISPE HPLC–LIF method can be applied to sensitively determine phloxine B in coffee bean

  6. Molecularly imprinted coated graphene oxide solid-phase extraction monolithic capillary column for selective extraction and sensitive determination of phloxine B in coffee bean

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Haiyun, E-mail: zhaihaiyun@126.com [College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006 (China); Su, Zihao [College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006 (China); Chen, Zuanguang, E-mail: chenzg@mail.sysu.edu.cn [School of Pharmaceutical Science, Sun Yat-sen University, Guangzhou 510006 (China); Liu, Zhenping; Yuan, Kaisong; Huang, Lu [College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006 (China)

    2015-03-20

    Highlights: • A new GO-MISPE monolithic capillary column was prepared. • The column showed ability of impurities removal and excellent selectivity. • Phloxine B existed in real sample was enriched more than 90 times. • The GO-MISPE column presented good recovery and high stability. • The method was prospered to analyze phloxine B and LOD achieved 0.3 ng g{sup −1}. - Abstract: A method was developed to sensitively determine phloxine B in coffee bean by molecularly imprinted polymers (MIPs) coated graphene oxide (GO) solid-phase extraction (GO-MISPE) coupled with high-performance liquid chromatography and laser-induced fluorescence detection (HPLC–LIF). The GO-MISPE capillary monolithic column was prepared by water-bath in situ polymerization, using GO as supporting material, phloxine B, methacrylic acid (MAA), and ethylene dimethacrylate (EDMA) as template, functional monomer, and cross-linker, respectively. The properties of the homemade GO-MISPE capillary monolithic column, including capacity and specificity, were investigated under optimized conditions. The GO-MIPs were characterized by scanning electron microscopy (SEM) and Fourier transform-infrared spectroscopy (FT-IR). The mean recoveries of phloxine B in coffee bean ranged from 89.5% to 91.4% and the intra-day and inter-day relative standard deviation (RSD) values all ranged from 3.6% to 4.7%. Good linearity was obtained over 0.001–2.0 μg mL{sup −1} (r = 0.9995) with the detection limit (S/N = 3) of 0.075 ng mL{sup −1}. Under the selected conditions, enrichment factors of over 90-fold were obtained and extraction on the monolithic column effectively cleaned up the coffee bean matrix. The results demonstrated that the proposed GO-MISPE HPLC–LIF method can be applied to sensitively determine phloxine B in coffee bean.

  7. Capillary detectors

    International Nuclear Information System (INIS)

    Konijn, J.; Winter, K.; Vilain, P.; Wilquet, G.; Fabre, J.P.; Kozarenko, E.; Kreslo, I.; Goldberg, J.; Hoepfner, K.; Bay, A.; Currat, C.; Koppenburg, P.; Frekers, D.; Wolff, T.; Buontempo, S.; Ereditato, A.; Frenkel, A.; Liberti, B.; Martellotti, G.; Penso, G.; Ekimov, A.; Golovkin, S.; Govorun, V.; Medvedkov, A.; Vasil'chenko, V.

    1998-01-01

    The option for a microvertex detector using glass capillary arrays filled with liquid scintillator is presented. The status of capillary layers development and possible read-out techniques for high rate environment are reported. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  8. Capillary ion chromatography with on-column focusing for ultra-trace analysis of methanesulfonate and inorganic anions in limited volume Antarctic ice core samples.

    Science.gov (United States)

    Rodriguez, Estrella Sanz; Poynter, Sam; Curran, Mark; Haddad, Paul R; Shellie, Robert A; Nesterenko, Pavel N; Paull, Brett

    2015-08-28

    Preservation of ionic species within Antarctic ice yields a unique proxy record of the Earth's climate history. Studies have been focused until now on two proxies: the ionic components of sea salt aerosol and methanesulfonic acid. Measurement of the all of the major ionic species in ice core samples is typically carried out by ion chromatography. Former methods, whilst providing suitable detection limits, have been based upon off-column preconcentration techniques, requiring larger sample volumes, with potential for sample contamination and/or carryover. Here, a new capillary ion chromatography based analytical method has been developed for quantitative analysis of limited volume Antarctic ice core samples. The developed analytical protocol applies capillary ion chromatography (with suppressed conductivity detection) and direct on-column sample injection and focusing, thus eliminating the requirement for off-column sample preconcentration. This limits the total sample volume needed to 300μL per analysis, allowing for triplicate sample analysis with Application to composite ice-core samples is demonstrated, with coupling of the capillary ion chromatograph to high resolution mass spectrometry used to confirm the presence and purity of the observed methanesulfonate peak. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. A new approach for the calculation of falling droplets from a cylindrical glass capillary based on force balance and velocity

    Science.gov (United States)

    Hummel, Sebastian; Bogner, Martin; Haub, Michael; Saegebarth, Joachim; Sandmaier, Hermann

    2017-11-01

    This paper presents a new simple analytical method to estimate the properties of falling droplets without solving complex differential equations. The derivation starts from the balance of forces and uses Newton’s second law and the equations of motion to calculate the volume of growing and detaching droplets and the time between two successive droplets falling out of a thin cylindrical capillary of borosilicate glass. In this specific case the reservoir is located above the capillary and the hydrostatic pressure of the fluid level leads to drop formation times about one second. In the second part of this paper experimental results are presented to validate the introduced calculation method. It is shown that the new approach describes the measuring results within a deviation of ±6.2%. The third part of the paper sums up the advantages of the new approach and an outlook is given on how the research on this topic will be continued.

  10. 46 CFR 52.01-110 - Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure gauges...

    Science.gov (United States)

    2010-10-01

    ... § 52.01-110 Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure... 46 Shipping 2 2010-10-01 2010-10-01 false Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure gauges (modifies PG-60). 52.01-110 Section 52.01-110 Shipping COAST...

  11. IMPACTS OF SMALL COLUMN ION EXCHANGE STREAMS ON DWPF GLASS FORMULATION: KT01, KT02, KT03, AND KT04-SERIES GLASS COMPOSITIONS

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K.; Edwards, T.

    2010-11-01

    Four series of glass compositions were selected, fabricated, and characterized as part of a study to determine the impacts of the addition of Crystalline Silicotitanate (CST) and Monosodium Titanate (MST) from the Small Column Ion Exchange (SCIX) process on the Defense Waste Processing Facility (DWPF) glass waste form and the applicability of the DWPF process control models. The KT01 and KT02-series of glasses were chosen to allow for the identification of the influence of the concentrations of major components of the glass on the retention of TiO{sub 2}. The KT03 series of glasses was chosen to allow for the identification of these influences when higher Nb{sub 2}O{sub 5} and ZrO{sub 2} concentrations are included along with TiO2. The KT04 series of glasses was chosen to investigate the properties and performance of glasses based on the best available projections of actual compositions to be processed at the DWPF (i.e., future sludge batches including the SCIX streams).

  12. Development and characterization of a novel plug and play liquid chromatography-mass spectrometry (LC-MS) source that automates connections between the capillary trap, column, and emitter.

    Science.gov (United States)

    Bereman, Michael S; Hsieh, Edward J; Corso, Thomas N; Van Pelt, Colleen K; Maccoss, Michael J

    2013-06-01

    We report the development and characterization of a novel, vendor-neutral ultra-high pressure-compatible (~10,000 p.s.i.) LC-MS source. This device is the first to make automated connections with user-packed capillary traps, columns, and capillary emitters. The source uses plastic rectangular inserts (referred to here as cartridges) where individual components (i.e. trap, column, or emitter) can be exchanged independent of one another in a plug and play manner. Automated robotic connections are made between the three cartridges using linear translation powered by stepper motors to axially compress each cartridge by applying a well controlled constant compression force to each commercial LC fitting. The user has the versatility to tailor the separation (e.g. the length of the column, type of stationary phase, and mode of separation) to the experimental design of interest in a cost-effective manner. The source is described in detail, and several experiments are performed to evaluate the robustness of both the system and the exchange of the individual trap and emitter cartridges. The standard deviation in the retention time of four targeted peptides from a standard digest interlaced with a soluble Caenorhabditis elegans lysate ranged between 3.1 and 5.3 s over 3 days of analyses. Exchange of the emitter cartridge was found to have an insignificant effect on the abundance of various peptides. In addition, the trap cartridge can be replaced with minimal effects on retention time (<20 s).

  13. Plasma L-ergothioneine measurement by high-performance liquid chromatography and capillary electrophoresis after a pre-column derivatization with 5-iodoacetamidofluorescein (5-IAF) and fluorescence detection.

    Science.gov (United States)

    Sotgia, Salvatore; Pisanu, Elisabetta; Pintus, Gianfranco; Erre, Gian Luca; Pinna, Gerard Aime; Deiana, Luca; Carru, Ciriaco; Zinellu, Angelo

    2013-01-01

    Two sensitive and reproducible capillary electrophoresis and high-performance liquid chromatography-fluorescence procedures were established for quantitative determination of L-egothioneine in plasma. After derivatization of L-ergothioneine with 5-iodoacetamidofluorescein, the separation was carried out by HPLC on an ODS-2 C-18 sperisorb column by using a linear gradient elution and by HPCE on an uncoated fused silica capillary, 50 µm id, and 60 cm length. The methods were validated and found to be linear in the range of 0.3 to 10 µmol/l. The limit of quantification was 0.27 µmol/l for HPCE and 0.15 µmol/l for HPLC. The variations for intra- and inter-assay precision were around 6 RSD%, and the mean recovery accuracy close to 100% (96.11%).

  14. Preparation and evaluation of open-tubular capillary columns modified with metal-organic framework incorporated polymeric porous layer for liquid chromatography.

    Science.gov (United States)

    Zhu, Manman; Zhang, Lingyi; Chu, Zhanying; Wang, Shulei; Chen, Kai; Zhang, Weibing; Liu, Fan

    2018-07-01

    An open tubular capillary liquid phase chromatographic column (1 m × 25 µm i.d.× 375 µm o.d.) was prepared by incorporating metal organic framework particles modified with vancomycin directly into zwitterionic polymer coating synthesized by the copolymerization of [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide and N,N'-methylenebisacrylamide. The incorporation of IRMOF-3 (isoreticular metal organic framework-3) particles improved selectivity of zwitterionic polymer coating with absolute column efficiency reaching 79900 plates for p-xylene. Besides strong hydrophilic interaction, the separation of neutral, basic, and acidic compounds demonstrates that π-π stacking interaction and the coordination effect of unsaturated Zn 2+ of MOF also contribute to separation of various analytes. The RSD values (run-to-run, day-to-day, column-to-column, n = 3) of retention time of neutral compounds were less than 0.71%, 0.69% and 3.08% respectively, suggesting good repeatability. In addition, the column was applied to the analysis of the trypsin digest of bovine serum albumin, revealing the potential in separating biological samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Comparison of experimental and Monte-Carlo simulation of MeV particle transport through tapered/straight glass capillaries and circular collimators

    Energy Technology Data Exchange (ETDEWEB)

    Hespeels, F., E-mail: felicien.hespeels@unamur.be [University of Namur, PMR, 61 rue de Bruxelles, 5000 Namur (Belgium); Tonneau, R. [University of Namur, PMR, 61 rue de Bruxelles, 5000 Namur (Belgium); Ikeda, T. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Lucas, S. [University of Namur, PMR, 61 rue de Bruxelles, 5000 Namur (Belgium)

    2015-11-01

    Highlights: • Monte-Carlo simulation for beam transportation through collimations devices. • We confirm the focusing effect of tapered glass capillary. • We confirm the feasibility of using passive collimation devices for ion beam analysis application. - Abstract: This study compares the capabilities of three different passive collimation devices to produce micrometer-sized beams for proton and alpha particle beams (1.7 MeV and 5.3 MeV respectively): classical platinum TEM-like collimators, straight glass capillaries and tapered glass capillaries. In addition, we developed a Monte-Carlo code, based on the Rutherford scattering theory, which simulates particle transportation through collimating devices. The simulation results match the experimental observations of beam transportation through collimators both in air and vacuum. This research shows the focusing effects of tapered capillaries which clearly enable higher transmission flux. Nevertheless, the capillaries alignment with an incident beam is a prerequisite but is tedious, which makes the TEM collimator the easiest way to produce a 50 μm microbeam.

  16. Preparation of a long-alkyl-chain-based hybrid monolithic column with mixed-mode interactions using a "one-pot" process for pressurized capillary electrochromatography.

    Science.gov (United States)

    Lyu, Haixia; Zhao, Heqing; Qin, Wenfei; Xie, Zenghong

    2017-12-01

    A simple "one-pot" approach for the preparation of a new vinyl-functionalized organic-inorganic hybrid monolithic column is described. In this improved method, the hydrolyzed alkoxysilanes of tetramethoxysilane and triethoxyvinylsilane were used as precursors for the synthesis of a silica-based monolith, while 1-hexadecene and sodium ethylenesulfonate were used as vinyl functional monomers along with azobisisobutyronitrile as an initiator. The effects of reaction temperature, urea content, and composition of organic monomers on the column properties (e.g. morphology, mechanical stability, and chromatographic performance) were investigated. The monolithic column was used for the separation of neutral solutes by reversed-phase pressurized capillary. Furthermore, the monolith can separate various aromatic amines, which indicated its excellent cation-exchange capability and hydrophobic interactions. The baseline separation of the aromatic amines was obtained with a column efficiency of up to 78 000 plates/m. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Preparation of polymer monolithic column functionalized by arsonic acid groups for mixed-mode capillary liquid chromatography.

    Science.gov (United States)

    Qin, Zhang-Na; Yu, Qiong-Wei; Wang, Ren-Qi; Feng, Yu-Qi

    2018-04-27

    A mixed-mode polymer monolithic column functionalized by arsonic acid groups was prepared by single-step in situ copolymerization of monomers p-methacryloylaminophenylarsonic acid (p-MAPHA) and pentaerythritol triacrylate (PETA). The prepared poly(p-MAPHA-co-PETA) monolithic column has a homogeneous monolithic structure with good permeability and mechanical stability. Zeta potential measurements reveal that the monolithic stationary phase holds a negative surface charge when the mobile phase resides in the pH range of 3.0-8.0. The retention mechanisms of prepared monolithic column are explored by the separation of selected polycyclic aromatic hydrocarbons (PAHs), nucleosides, and three basic compounds. The results indicate that the column functions in three different separation modes associated with reversed-phase chromatography based on hydrophobic interaction, hydrophilic interaction chromatography, and cation-exchange chromatography. The column efficiency of prepared monolithic column is estimated to be 70,000 and 76,000 theoretical plates/m for thiourea and naphthalene, respectively, at a linear flow velocity of 0.85 mm/s using acetonitrile/H 2 O (85/15, v/v) as the mobile phase. Furthermore, an analysis of the retention factors obtained for the PAHs indicates that the prepared monolithic column exhibits good reproducibility with relative standard deviations of 2.9%, 4.0%, and 4.7% based on run-to-run injections, column-to-column preparation, and batch-to-batch preparation, respectively. Finally, we investigate the separation performance of the proposed monolithic column for select phenols, sulfonamides, nucleobases and nucleosides. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Temperature-based on-column solute focusing in capillary liquid chromatography reduces peak broadening from precolumn dispersion and volume overload when used alone or with solvent-based focusing

    Science.gov (United States)

    Groskreutz, Stephen R.; Horner, Anthony R.; Weber, Stephen G.

    2015-01-01

    On-column focusing is essential for satisfactory performance using capillary scale columns. On-column focusing results from generating transient conditions at the head of the column that lead to high solute retention. Solvent-based on-column focusing is a well-known approach to achieve this. Temperature-assisted on-column focusing (TASF) can also be effective. TASF improves focusing by cooling a short segment of the column inlet to a temperature that is lower than the column temperature during the injection and then rapidly heating the focusing segment to the match the column temperature. A troublesome feature of an earlier implementation of TASF was the need to leave the capillary column unpacked in that portion of the column inside the fitting connecting it to the injection valve. We have overcome that problem in this work by packing the head of the column with solid silica spheres. In addition, technical improvements to the TASF instrumentation include: selection of a more powerful thermo-electric cooler to create faster temperature changes and electronic control for easy incorporation into conventional capillary instruments. Used in conjunction with solvent-based focusing and with isocratic elution, volumes of paraben samples (esters of p-hydroxybenzoic acid) up to 4.5-times the column liquid volume can be injected without significant bandspreading due to volume overload. Interestingly, the shapes of the peaks from the lowest volume injections that we can make, 30 nL, are improved when using TASF. TASF is very effective at reducing the detrimental effects of precolumn dispersion using isocratic elution. Finally, we show that TASF can be used to focus the neuropeptide galanin in a sample solvent with elution strength stronger than the mobile phase. Here, the stronger solvent is necessitated by the need to prevent peptide adsorption prior to and during analysis. PMID:26091787

  19. Monolithic columns based on a poly(styrene-divinylbenzene-methacrylic acid) copolymer for capillary liquid chromatography of small organic molecules

    Czech Academy of Sciences Publication Activity Database

    Svobodová, A.; Křížek, T.; Širc, Jakub; Šálek, Petr; Tesařová, E.; Coufal, P.; Štulík, K.

    2011-01-01

    Roč. 1218, č. 11 (2011), s. 1544-1547 ISSN 0021-9673 R&D Projects: GA AV ČR KAN200520804 Institutional research plan: CEZ:AV0Z40500505 Keywords : capillary liquid chromatography * methacrylic acid * polystyrene-based monolithic stationary phase Subject RIV: EI - Biotechnology ; Bionics Impact factor: 4.531, year: 2011

  20. Poly(norepinephrine)-coated open tubular column for the separation of proteins and recombination human erythropoietin by capillary electrochromatography.

    Science.gov (United States)

    Xiao, Xue; Zhang, Yamin; Wu, Jia; Jia, Li

    2017-12-01

    Recombinant human erythropoietin is an important therapeutic protein with high economic interest due to the benefits provided by its clinical use for the treatment of anemias associated with chronic renal failure and chemotherapy. In this work, a poly(norepinephrine)-coated open tubular column was successfully prepared based on the self-polymerization of norepinephrine under mild alkaline condition, the favorable film forming and easy adhesive properties of poly(norepinephrine). The poly(norepinephrine) coating was characterized by scanning electron microscopy and measurement of the electro-osmotic flow. The thickness of the coating was about 431 nm. The electrochromatographic performance of the poly(norepinephrine)-coated open tubular column was evaluated by separation of proteins. Some basic and acidic proteins including two variants of bovine serum albumin and two variants of β-lactoglobulin achieved separation in the poly(norepinephrine)-coated open tubular column. More importantly, the column demonstrated separation ability for the glycoforms of recombinant human erythropoietin. In addition, the column demonstrated good repeatability with the run-to-run, day-to-day, and column-to-column relative standard deviations of migration times of proteins less than 3.40%. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Colloid mobilization and transport during capillary fringe fluctuations.

    Science.gov (United States)

    Aramrak, Surachet; Flury, Markus; Harsh, James B; Zollars, Richard L

    2014-07-01

    Capillary fringe fluctuations due to changing water tables lead to displacement of air-water interfaces in soils and sediments. These moving air-water interfaces can mobilize colloids. We visualized colloids interacting with moving air-water interfaces during capillary fringe fluctuations by confocal microscopy. We simulated capillary fringe fluctuations in a glass-bead-filled column. We studied four specific conditions: (1) colloids suspended in the aqueous phase, (2) colloids attached to the glass beads in an initially wet porous medium, (3) colloids attached to the glass beads in an initially dry porous medium, and (4) colloids suspended in the aqueous phase with the presence of a static air bubble. Confocal images confirmed that the capillary fringe fluctuations affect colloid transport behavior. Hydrophilic negatively charged colloids initially suspended in the aqueous phase were deposited at the solid-water interface after a drainage passage, but then were removed by subsequent capillary fringe fluctuations. The colloids that were initially attached to the wet or dry glass bead surface were detached by moving air-water interfaces in the capillary fringe. Hydrophilic negatively charged colloids did not attach to static air-bubbles, but hydrophobic negatively charged and hydrophilic positively charged colloids did. Our results demonstrate that capillary fringe fluctuations are an effective means for colloid mobilization.

  2. One-pot preparation of a mixed-mode organic-silica hybrid monolithic capillary column and its application in determination of endogenous gibberellins in plant tissues.

    Science.gov (United States)

    Zhang, Zheng; Hao, Yan-Hong; Ding, Jun; Xu, Sheng-Nan; Yuan, Bi-Feng; Feng, Yu-Qi

    2015-10-16

    A newly improved one-pot method, based on "thiol-ene" click chemistry and sol-gel approach in microemulsion system, was developed for the preparation of C8/PO(OH)2-silica hybrid monolithic capillary column. The prepared monolith possesses large specific surface area, narrow mesopore size distribution and high column efficiency. The monolithic column was demonstrated to have cation exchange/reversed-phase (CX/RP) mixed-mode retention for analytes on nano-liquid chromatography (nano-LC). On the basis of the developed nano-LC system with MS detector coupled to pipette tip solid phase extraction (PT-SPE) and derivatization process, we then realized simultaneous determination of 10 gibberellins (GAs) with low limits of detection (LODs, 0.003-0.025 ng/mL). Furthermore, 6 endogenous GAs in only 5mg rice leaves (fresh weight) were successfully detected and quantified. The developed PT-SPE-nano-LC-MS strategy may offer promising applications in the determination of low abundant bioactive molecules from complex matrix. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Preparation of a β-Cyclodextrin-Based Open-Tubular Capillary Electrochromatography Column and Application for Enantioseparations of Ten Basic Drugs.

    Directory of Open Access Journals (Sweden)

    Linlin Fang

    Full Text Available An open-tubular capillary electrochromatography column was prepared by chemically immobilized β-cyclodextrin modified gold nanoparticles onto new surface with the prederivatization of (3-mercaptopropyl-trimethoxysilane. The synthesized nanoparticles and the prepared column were characterized by transmission electron microscopy, scanning electron microscopy, infrared spectroscopy and ultraviolet visible spectroscopy. When the column was employed as the chiral stationary phase, no enantioselectivity was observed for ten model basic drugs. So β-cyclodextrin was added to the background electrolyte as chiral additive to expect a possible synergistic effect occurring and resulting in a better separation. Fortunately, significant improvement in enantioselectivity was obtained for ten pairs of drug enantiomers. Then, the effects of β-cyclodextrin concentration and background electrolyte pH on the chiral separation were investigated. With the developed separation mode, all the enantiomers (except for venlafaxine were baseline separated in resolutions of 4.49, 1.68, 1.88, 1.57, 2.52, 2.33, 3.24, 1.63 and 3.90 for zopiclone, chlorphenamine maleate, brompheniramine maleate, dioxopromethazine hydrochloride, carvedilol, homatropine hydrobromide, homatropine methylbromide, venlafaxine, sibutramine hydrochloride and terbutaline sulfate, respectively. Further, the possible separation mechanism involved was discussed.

  4. Effect of gravity on colloid transport through water-saturated columns packed with glass beads: modeling and experiments.

    Science.gov (United States)

    Chrysikopoulos, Constantinos V; Syngouna, Vasiliki I

    2014-06-17

    The role of gravitational force on colloid transport in water-saturated columns packed with glass beads was investigated. Transport experiments were performed with colloids (clays: kaolinite KGa-1b, montmorillonite STx-1b). The packed columns were placed in various orientations (horizontal, vertical, and diagonal) and a steady flow rate of Q = 1.5 mL/min was applied in both up-flow and down-flow modes. All experiments were conducted under electrostatically unfavorable conditions. The experimental data were fitted with a newly developed, analytical, one-dimensional, colloid transport model. The effect of gravity is incorporated in the mathematical model by combining the interstitial velocity (advection) with the settling velocity (gravity effect). The results revealed that flow direction influences colloid transport in porous media. The rate of particle deposition was shown to be greater for up-flow than for down-flow direction, suggesting that gravity was a significant driving force for colloid deposition.

  5. Polar and nonpolar organic polymer-based monolithic columns for capillary electrochromatography and high-performance liquid chromatography.

    Science.gov (United States)

    Rathnasekara, Renuka; Khadka, Shantipriya; Jonnada, Murthy; El Rassi, Ziad

    2017-01-01

    This review article is a continuation of the previous reviews on the area of monolithic columns covering the progress made in the field over the last couple of years from the beginning of the second half of 2014 until the end of the first half of 2016. It summarizes and evaluates the evolvement of both polar and nonpolar organic monolithic columns and their use in hydrophilic interaction LC and CEC and reversed-phase chromatography and RP-CEC. The review article discusses the results reported in a total of 62 references. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Simultaneous separation of water- and fat-soluble vitamins in isocratic pressure-assisted capillary electrochromatography using a methacrylate-based monolithic column.

    Science.gov (United States)

    Yamada, Hiroki; Kitagawa, Shinya; Ohtani, Hajime

    2013-06-01

    A method of simultaneous separation of water- and fat-soluble vitamins using pressure-assisted CEC with a methacrylate-based capillary monolithic column was developed. In the proposed method, water-soluble vitamins were mainly separated electrophoretically, while fat soluble-ones were separated chromatographically by the interaction with a methacrylate-based monolith. A mixture of six water-soluble and four fat-soluble vitamins was separated simultaneously within 20 min with an isocratic elution using 1 M formic acid (pH 1.9)/acetonitrile (30:70, v/v) containing 10 mM ammonium formate as a mobile phase. When the method was applied to a commercial multivitamin tablet and a spiked one, the vitamins were successfully analyzed, and no influence of the matrix contained in the tablet was observed. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Automatic and integrated micro-enzyme assay (AIμEA) platform for highly sensitive thrombin analysis via an engineered fluorescence protein-functionalized monolithic capillary column.

    Science.gov (United States)

    Lin, Lihua; Liu, Shengquan; Nie, Zhou; Chen, Yingzhuang; Lei, Chunyang; Wang, Zhen; Yin, Chao; Hu, Huiping; Huang, Yan; Yao, Shouzhuo

    2015-04-21

    Nowadays, large-scale screening for enzyme discovery, engineering, and drug discovery processes require simple, fast, and sensitive enzyme activity assay platforms with high integration and potential for high-throughput detection. Herein, a novel automatic and integrated micro-enzyme assay (AIμEA) platform was proposed based on a unique microreaction system fabricated by a engineered green fluorescence protein (GFP)-functionalized monolithic capillary column, with thrombin as an example. The recombinant GFP probe was rationally engineered to possess a His-tag and a substrate sequence of thrombin, which enable it to be immobilized on the monolith via metal affinity binding, and to be released after thrombin digestion. Combined with capillary electrophoresis-laser-induced fluorescence (CE-LIF), all the procedures, including thrombin injection, online enzymatic digestion in the microreaction system, and label-free detection of the released GFP, were integrated in a single electrophoretic process. By taking advantage of the ultrahigh loading capacity of the AIμEA platform and the CE automatic programming setup, one microreaction column was sufficient for many times digestion without replacement. The novel microreaction system showed significantly enhanced catalytic efficiency, about 30 fold higher than that of the equivalent bulk reaction. Accordingly, the AIμEA platform was highly sensitive with a limit of detection down to 1 pM of thrombin. Moreover, the AIμEA platform was robust and reliable to detect thrombin in human serum samples and its inhibition by hirudin. Hence, this AIμEA platform exhibits great potential for high-throughput analysis in future biological application, disease diagnostics, and drug screening.

  8. Digital microfluidics platform for interfacing solid-liquid extraction column with portable capillary electropherograph for analysis of soil amino acids.

    Science.gov (United States)

    Gorbatsova, Jelena; Jaanus, Martin; Vaher, Merike; Kaljurand, Mihkel

    2016-02-01

    In this work, the concept of a field-portable analyzer is proposed that operates with milliliter amounts of solvents and samples. The need to develop such an analyzer is not only driven by specific extraterrestrial analysis but also, for example, by forensics applications where the amount of liquid that can be taken to the field is severely limited. The prototype of the proposed analyzer consists of a solid-liquid extractor, the output of which is connected to the micropump, which delivers droplets of extracts to digital microfluidic platform (DMFP). In this way, world-to-chip interfacing is established. Further, the sample droplets are transported to CE capillary inlet port, separated and detected via a contactless conductivity detector. Working buffers and other solvents needed to perform CE analysis are also delivered as droplets to the DMFP and transported through the CE capillary. The performance of the analyzer is demonstrated by analysis of amino acids in sand matrices. The recovery of the spiked amino acids from the inert sand sample was from 34 to 51% with analysis LOD from 0.2 to 0.6 ppm and migration time RSD from 0.2 to 6.0%. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Development of micro-beam NRA for 3D-mapping of hydrogen distribution in solids: Application of tapered glass capillary to 6 MeV 15N ion

    International Nuclear Information System (INIS)

    Sekiba, D.; Yonemura, H.; Nebiki, T.; Wilde, M.; Ogura, S.; Yamashita, H.; Matsumoto, M.; Kasagi, J.; Iwamura, Y.; Itoh, T.; Matsuzaki, H.; Narusawa, T.; Fukutani, K.

    2008-01-01

    A micro-beam NRA system, by means of a resonant nuclear reaction 1 H( 15 N, αγ) 12 C, has been developed for the purpose of the 3D mapping of the hydrogen distribution in solids. To obtain the tens μm size of the beam spot, the combination of the newly proposed tapered glass capillary and a conventional quadrupole magnetic lens is employed. An Y patterned film on a substrate is prepared as an application of the developed system. The 6 MeV 15 N beam focused by glass capillaries down to 50 μm successfully shows the hydrogen distribution. The in-plane NRA profile implies that the beam emitted from the glass capillary outlet is parallel, although the original beam has a considerable divergence. The NRA measurements in the 10 3 Pa N 2 atmosphere due to the low gas conductance of the glass capillary is also demonstrated

  10. Trace analysis of halogenated hydrocarbons in gaseous samples by on-line enrichment in an adsorption trap, on-column cold-trapping and capillary gas chromatography. I.Method and instrumentation

    NARCIS (Netherlands)

    Noij, T.H.M.; Fabian, P.; Borchers, R.; Janssen, F.; Cramers, C.A.M.G.; Rijks, J.A.

    1987-01-01

    A method is described for the determination of halocarbons in gaseous samples down to the ppt level (1:1012, v/v), consisting of successive on-line sub-ambient enrichment on an adsorbent, on-column cryofocusing, capillary gas chromatography and electron-capture detection. The quantitative aspects of

  11. Determination of ammonium in wastewaters by capillary electrophoresis on a column-coupling chip with conductivity detection.

    Science.gov (United States)

    Luc, Milan; Kruk, Pavol; Masár, Marián

    2011-07-01

    Analytical potentialities of a chip-based CE in determination of ammonium in wastewaters were investigated. CZE with the electric field and/or ITP sample stacking was performed on a column-coupling (CC) chip with integrated conductivity detectors. Acetate background electrolytes (pH ∼3) including 18-crown-6-ether (18-crown-6) and tartaric acid were developed to reach rapid (in 7-8 min) CZE and ITP-CZE resolutions of ammonium from other cations (sodium, potassium, calcium and magnesium) present in wastewater samples. Under preferred working conditions (suppressed hydrodynamic flow (HDF) and EOF on the column-coupling chip), both the employed methods did provide very good repeatabilities of the migration (RSD of 0.2-0.8% for the migration time) and quantitative (RSD of 0.3-4.9% for the peak area) parameters in the model and wastewater samples. Using a 900-nL sample injection volume, LOD for ammonium were obtained at 20 and 40 μg/L concentrations in CZE and ITP-CZE separations, respectively. Very good agreements of the CZE and ITP-CZE determinations of ammonium in six untreated wastewater samples (only filtration and dilution) with the results obtained by a reference spectrometric method indicate a very good accuracy of both the CE methods presented. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Behaviour of reinforced columns with E_Glass fiber and carbon fiber

    OpenAIRE

    BOUCHELAGHEM Hafida; BEZAZI Abederrezak; Benzanache Naziha; SCARPA Fabrizio

    2018-01-01

    Externally bonded reinforcement using Fiber Reinforced Polymer (FRP) is a good response to the concern represented by the need for rehabilitation of concrete structures. These techniques are more and more attractive because of their fast and low labour costs, very good strength to weight ratio, good fatigue properties, and non-corrosive characteristics of FRP. The present work is an experimental study investigating the mechanical behaviour under a uni-axial loading of short concrete columns r...

  13. Gas dispersion concentration of trace inorganic contaminants from fuel gas and analysis using head-column field-amplified sample stacking capillary electrophoresis.

    Science.gov (United States)

    Yang, Jianmin; Li, Hai-Fang; Li, Meilan; Lin, Jin-Ming

    2012-08-21

    The presence of inorganic elements in fuel gas generally accelerates the corrosion and depletion of materials used in the fuel gas industry, and even leads to serious accidents. For identification of existing trace inorganic contaminants in fuel gas in a portable way, a highly efficient gas-liquid sampling collection system based on gas dispersion concentration is introduced in this work. Using the constructed dual path gas-liquid collection setup, inorganic cations and anions were simultaneously collected from real liquefied petroleum gas (LPG) and analyzed by capillary electrophoresis (CE) with indirect UV absorbance detection. The head-column field-amplified sample stacking technique was applied to improve the detection limits to 2-25 ng mL(-1). The developed collection and analytical methods have successfully determined existing inorganic contaminants in a real LPG sample in the range of 4.59-138.69 μg m(-3). The recoveries of cations and anions with spiked LPG samples were between 83.98 and 105.63%, and the relative standard deviations (RSDs) were less than 7.19%.

  14. Incorporation of metal-organic framework HKUST-1 into porous polymer monolithic capillary columns to enhance the chromatographic separation of small molecules.

    Science.gov (United States)

    Yang, Shengchao; Ye, Fanggui; Lv, Qinghui; Zhang, Cong; Shen, Shufen; Zhao, Shulin

    2014-09-19

    Metal-organic framework (MOF) HKUST-1 nanoparticles have been incorporated into poly(glycidyl methacrylate-co-ethylene dimethacrylate) (HKUST-1-poly(GMA-co-EDMA)) monoliths to afford stationary phases with enhanced chromatographic performance of small molecules in the reversed phase capillary liquid chromatography. The effect of HKUST-1 nanoparticles in the polymerization mixture on the performance of the monolithic column was explored in detail. While the bare poly(GMA-co-EDMA) monolith exhibited poor resolution (RsHKUST-1 nanoparticles to the polymerization mixture provide high increased resolution (Rs≥1.3) and high efficiency ranged from 16,300 to 44,300plates/m. Chromatographic performance of HKUST-1-poly(GMA-co-EDMA) monolith was demonstrated by separation of various analytes including polycyclic aromatic hydrocarbons, ethylbenzene and styrene, phenols and aromatic acids using a binary polar mobile phase (CH3CN/H2O). The HKUST-1-poly(GMA-co-EDMA) monolith displayed enhanced hydrophobic and π-π interaction characteristics in the reversed phase separation of test analytes compared to the bare poly(GMA-co-EDMA) monolith. The experiment results showed that HKUST-1-poly(GMA-co-EDMA) monoliths are an alternative to enhance the chromatographic separation of small molecules. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Depth dependent microbial carbon use efficiency in the capillary fringe as affected by water table fluctuations in a column incubation experiment

    Science.gov (United States)

    Pronk, G. J.; Mellage, A.; Milojevic, T.; Smeaton, C. M.; Rezanezhad, F.; Van Cappellen, P.

    2017-12-01

    Microbial growth and turnover of soil organic carbon (SOC) depend on the availability of electron donors and acceptors. The steep geochemical gradients in the capillary fringe between the saturated and unsaturated zones provide hotspots of soil microbial activity. Water table fluctuations and the associated drying and wetting cycles within these zones have been observed to lead to enhanced turnover of SOC and adaptation of the local microbial communities. To improve our understanding of SOC degradation under changing moisture conditions, we carried out an automated soil column experiment with integrated of hydro-bio-geophysical monitoring under both constant and oscillating water table conditions. An artificial soil mixture composed of quartz sand, montmorillonite, goethite and humus was used to provide a well-defined system. This material was inoculated with a microbial community extracted from a forested riparian zone. The soils were packed into 6 columns (60 cm length and 7.5 cm inner diameter) to a height of 45 cm; and three replicate columns were incubated under constant water table while another three were saturated and drained monthly. The initial soil development, carbon cycling and microbial community development were then characterized during 10 months of incubation. This system provides an ideal artificial gradient from the saturated to the unsaturated zone to study soil development from initially homogeneous materials and the same microbial community composition under controlled conditions. Depth profiles of SOC and microbial biomass after 329 days of incubation showed a depletion of carbon in the transition drying and wetting zone that was not associated with higher accumulation of microbial biomass, indicating a lower carbon use efficiency of the microbial community established within the water table fluctuation zone. This was supported by a higher ATP to microbial biomass carbon ratio within the same zone. The findings from this study highlight the

  16. Cotransport of clay colloids and viruses through water-saturated vertically oriented columns packed with glass beads: Gravity effects.

    Science.gov (United States)

    Syngouna, Vasiliki I; Chrysikopoulos, Constantinos V

    2016-03-01

    The cotransport of clay colloids and viruses in vertically oriented laboratory columns packed with glass beads was investigated. Bacteriophages MS2 and ΦX174 were used as model viruses, and kaolinite (ΚGa-1b) and montmorillonite (STx-1b) as model clay colloids. A steady flow rate of Q=1.5 mL/min was applied in both vertical up (VU) and vertical down (VD) flow directions. In the presence of KGa-1b, estimated mass recovery values for both viruses were higher for VD than VU flow direction, while in the presence of STx-1b the opposite was observed. However, for all cases examined, the produced mass of viruses attached onto suspended clay particles were higher for VD than VU flow direction, suggesting that the flow direction significantly influences virus attachment onto clays, as well as packed column retention of viruses attached onto suspended clays. KGa-1b hindered the transport of ΦX174 under VD flow, while STx-1b facilitated the transport of ΦX174 under both VU and VD flow directions. Moreover, KGa-1b and STx-1b facilitated the transport of MS2 in most of the cases examined except of the case where KGa-1b was present under VD flow. Also, the experimental data were used for the estimation of virus surface-coverages and virus surface concentrations generated by virus diffusion-limited attachment, as well as virus attachment due to sedimentation. Both sedimentation and diffusion limited virus attachment were higher for VD than VU flow, except the case of MS2 and STx-1b cotransport. The diffusion-limited attachment was higher for MS2 than ΦΧ174 for all cases examined. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Analysis of bovine milk caseins on organic monolithic columns: an integrated capillary liquid chromatography-high resolution mass spectrometry approach for the study of time-dependent casein degradation.

    Science.gov (United States)

    Pierri, Giuseppe; Kotoni, Dorina; Simone, Patrizia; Villani, Claudio; Pepe, Giacomo; Campiglia, Pietro; Dugo, Paola; Gasparrini, Francesco

    2013-10-25

    Casein proteins constitute approximately 80% of the proteins present in bovine milk and account for many of its nutritional and technological properties. The analysis of the casein fraction in commercially available pasteurized milk and the study of its time-dependent degradation is of considerable interest in the agro-food industry. Here we present new analytical methods for the study of caseins in fresh and expired bovine milk, based on the use of lab-made capillary organic monolithic columns. An integrated capillary high performance liquid chromatography and high-resolution mass spectrometry (Cap-LC-HRMS) approach was developed, exploiting the excellent resolution, permeability and biocompatibility of organic monoliths, which is easily adaptable to the analysis of intact proteins. The resolution obtained on the lab-made Protein-Cap-RP-Lauryl-γ-Monolithic column (270 mm × 0.250 mm length × internal diameter, L × I.D.) in the analysis of commercial standard caseins (αS-CN, β-CN and κ-CN) through Cap-HPLC-UV was compared to the one observe using two packed capillary C4 columns, the ACE C4 (3 μm, 150 mm × 0.300 mm, L × I.D.) and the Jupiter C4 column (5 μm, 150 mm × 0.300 mm, L × I.D.). Thanks to the higher resolution observed, the monolithic capillary column was chosen for the successive degradation studies of casein fractions extracted from bovine milk 1-4 weeks after expiry date. The comparison of the UV chromatographic profiles of skim, semi-skim and whole milk showed a major stability of whole milk towards time-dependent degradation of caseins, which was further sustained by high-resolution analysis on a 50-cm long monolithic column using a 120-min time gradient. Contemporarily, the exact monoisotopic and average molecular masses of intact αS-CN and β-CN protein standards were obtained through high resolution mass spectrometry and used for casein identification in Cap-LC-HRMS analysis. Finally, the proteolytic degradation of β-CN in skim milk

  18. Determination of Wastewater Compounds in Sediment and Soil by Pressurized Solvent Extraction, Solid-Phase Extraction, and Capillary-Column Gas Chromatography/Mass Spectrometry

    Science.gov (United States)

    Burkhardt, Mark R.; Zaugg, Steven D.; Smith, Steven G.; ReVello, Rhiannon C.

    2006-01-01

    A method for the determination of 61 compounds in environmental sediment and soil samples is described. The method was developed in response to increasing concern over the effects of endocrine-disrupting chemicals in wastewater and wastewater-impacted sediment on aquatic organisms. This method also may be used to evaluate the effects of combined sanitary and storm-sewer overflow on the water and sediment quality of urban streams. Method development focused on the determination of compounds that were chosen on the basis of their endocrine-disrupting potential or toxicity. These compounds include the alkylphenol ethoxylate nonionic surfactants and their degradates, food additives, fragrances, antioxidants, flame retardants, plasticizers, industrial solvents, disinfectants, fecal sterols, polycyclic aromatic hydrocarbons, and high-use domestic pesticides. Sediment and soil samples are extracted using a pressurized solvent extraction system. The compounds of interest are extracted from interfering matrix components by high-pressure water/isopropyl alcohol extraction. The compounds were isolated using disposable solid-phase extraction (SPE) cartridges containing chemically modified polystyrene-divinylbenzene resin. The cartridges were dried with nitrogen gas, and then sorbed compounds were eluted with methylene chloride (80 percent)-diethyl ether (20 percent) through Florisil/sodium sulfate SPE cartridge, and then determined by capillary-column gas chromatography/mass spectrometry. Recoveries in reagent-sand samples fortified at 4 to 72 micrograms averaged 76 percent ?13 percent relative standard deviation for all method compounds. Initial method reporting levels for single-component compounds ranged from 50 to 500 micrograms per kilogram. The concentrations of 20 out of 61 compounds initially will be reported as estimated with the 'E' remark code for one of three reasons: (1) unacceptably low-biased recovery (less than 60 percent) or highly variable method performance

  19. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of semivolatile organic compounds in bottom sediment by solvent extraction, gel permeation chromatographic fractionation, and capillary-column gas chromatography/mass spectrometry

    Science.gov (United States)

    Furlong, E.T.; Vaught, D.G.; Merten, L.M.; Foreman, W.T.; Gates, Paul M.

    1996-01-01

    A method for the determination of 79 semivolatile organic compounds (SOCs) and 4 surrogate compounds in soils and bottom sediment is described. The SOCs are extracted from bottom sediment by solvent extraction, followed by partial isolation using high-performance gel permeation chromatography (GPC). The SOCs then are qualitatively identified and quantitative concentrations determined by capillary-column gas chromatography/mass spectrometry (GC/MS). This method also is designed for an optional simultaneous isolation of polychlorinated biphenyls (PCBs) and organochlorine (OC) insecticides, including toxaphene. When OCs and PCBs are determined, an additional alumina- over-silica column chromatography step follows GPC cleanup, and quantitation is by dual capillary- column gas chromatography with electron-capture detection (GC/ECD). Bottom-sediment samples are centrifuged to remove excess water and extracted overnight with dichloromethane. The extract is concentrated, centrifuged, and then filtered through a 0.2-micrometer polytetrafluoro-ethylene syringe filter. Two aliquots of the sample extract then are quantitatively injected onto two polystyrene- divinylbenzene GPC columns connected in series. The SOCs are eluted with dichloromethane, a fraction containing the SOCs is collected, and some coextracted interferences, including elemental sulfur, are separated and discarded. The SOC-containing GPC fraction then is analyzed by GC/MS. When desired, a second aliquot from GPC is further processed for OCs and PCBs by combined alumina-over-silica column chromatography. The two fractions produced in this cleanup then are analyzed by GC/ECD. This report fully describes and is limited to the determination of SOCs by GC/MS.

  20. Ion-pair in-tube solid-phase microextraction and capillary liquid chromatography using a titania-based column: application to the specific lauralkonium chloride determination in water.

    Science.gov (United States)

    Prieto-Blanco, M C; Moliner-Martínez, Y; López-Mahía, P; Campíns-Falcó, P

    2012-07-27

    A quick, miniaturized and on-line method has been developed for the determination in water of the predominant homologue of benzalkonium chloride, dodecyl dimethyl benzyl ammonium chloride or lauralkonium chloride (C(12)-BAK). The method is based on the formation of an ion-pair in both in-tube solid-phase microextraction (IT-SPME) and capillary liquid chromatography. The IT-SPME optimization required the study of the length and nature of the stationary phase of capillary and the processed sample volume. Because to the surfactant character of the analyte both, the extracting and replacing solvents, have played a decisive role in the IT-SPME optimized procedure. Conditioning the capillary with the mobile phase which contains the counter ion (acetate), using an organic additive (tetrabutylammonium chloride) added to the sample and a mixture water/methanol as replacing solvent (processed just before the valve is switched to the inject position), allowed to obtain good precision of the retention time and a narrow peak for C(12)-BAK. A reversed-phase capillary based TiO(2) column and a mobile phase containing ammonium acetate at pH 5.0 for controlling the interactions of cationic surfactant with titania surface were proposed. The optimized procedure provided adequate linearity, accuracy and precision at the concentrations interval of 1.5-300 μg L(-1) .The limit of detection (LOD) was 0.5 μg L(-1) using diode array detection (DAD). The applicability of proposed IT-SPME-capillary LC method has been assessed in several water samples. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Applications of capillary optics for focused ion beams

    International Nuclear Information System (INIS)

    Umezawa, Kenji

    2014-01-01

    This article introduces applications of focused ion beams (∼1 μm) with glass capillaries systems. A first report on the interaction between ion beams and glass capillaries was published in 1996. The guiding capabilities of glass capillaries were discovered due to ion reflection from inner wall of glass surfaces. Meanwhile, the similar optics have been already realized in focusing X-rays using glass capillaries. The basic technology of X-rays optics using glass capillaries had been developed in the 1980's and 1900's. Also, low energy atom scattering spectroscopy for insulator material analysis will be mentioned. (author)

  2. Potential of capillary-column-switching liquid chromatography-tandem mass spectrometry for the quantitative trace analysis of small molecules. Application to the on-line screening of drugs in water.

    Science.gov (United States)

    Pitarch, Elena; Hernandez, Felix; ten Hove, Jan; Meiring, Hugo; Niesing, Willem; Dijkman, Ellen; Stolker, Linda; Hogendoorn, Elbert

    2004-03-26

    We have investigated the potential of capillary-column-switching liquid chromatography coupled to tandem mass spectrometry (cLC-MS-MS) for the quantitative on-line trace analysis of target compounds in aqueous solutions. The technical design of the nano-scale cLC system developed at our Institute for peptide and protein identification has been tested and evaluated for the direct trace analysis of drugs in water samples. Sulphametoxazole, bezafibrate, metoprolol, carbamazepine and bisoprolol occurring frequently in Dutch waters, were selected as test compounds. Adequate conditions for trapping, elution and MS-MS detection were investigated by employing laboratory made 200 microm i.d. capillary columns packed with 5 microm aqua C18 material. In the final cLC-MS-MS conditions, a 1 cm length trapping column and a 4 cm length analytical column were selected. Under these conditions, the target compounds could be directly determined in water down to a level of around 50 ng/l employing only 25 microl of water sample. Validation was done by recovery experiments in ground-, surface- and drinking-water matrices as well as by the analysis of water samples with incurred residues and previously analyzed with a conventional procedure involving off-line solid-phase extraction and narrow-bore LC with MS-MS detection. The new methodology provided recoveries (50-500 ng/l level) between 50 and 114% with RSDs (n = 3, each level) below 20% for most of the compounds. Despite the somewhat less analytical performance in comparison to the conventional procedure, the on-line approach of the new methodology is very suitable for screening of drugs in aqueous samples.

  3. Capillary electrophoresis of chitooligosaccharides in acidic solution: simple determination using a quaternary-ammonium-modified column and indirect photometric detection with crystal violet.

    Science.gov (United States)

    Hattori, Toshiaki; Anraku, Nobuhiro; Kato, Ryo

    2010-02-01

    Five chitosan oligosaccharides were separated in acidic aqueous solution by capillary electrophoresis (CE) with indirect photometric detection using a positively coated capillary. Electrophoretic mobility of the chitooligosaccharides (COSs) depended on the number of monomer units in acidic aqueous solution, similar to other polyelectrolyte oligomers. The separation was developed in nitric acid aqueous solution at pH 3.0 with 1 mM Crystal Violet, using a capillary positively coated with N-trimethoxypropyl-N,N,N-trimethylammonium chloride. The limit of the detection for chitooligosaccharides with two to six saccharide chains was less than 5 microM. CE determination of an enzymatically hydrolyzed COS agreed with results from HPLC. 2009 Elsevier B.V. All rights reserved.

  4. A fast and accurate method for the pharmacokinetic research of four coumarin analogs in Fructus cnidii using capillary electro-chromatography with a methacrylate ester-based monolithic column.

    Science.gov (United States)

    Chen, Zhao; Xu, Aili; Bi, Xiaoli; Luo, Wenhui; Li, Ji; Fan, Guorong; Sun, Dongmei

    2017-11-01

    In the present study, a monolithic capillary column with higher permeability was developed for the in vivo discrimination of four coumarin analogs (bergapten, 2'-acetylangelicin, imperatorin, and osthole) that typically require long separation times in HPLC. Instead of conventional methacrylate ester monolith (containing 19.5% porogen) with insufficient permeability (K = 1.52 - 1.66 × 10 -14 M 2 ) for plasma sample, the proposed column (20.5% porogen) had better permeability (around 3.80 × 10 -14 M 2 ) while properties such as pore distribution, stability, and resolution changed slightly. As a result, due to the negatively charged electro-dynamic flow of the methacrylate ester groups in the monolith, the migration of targeted analytes was achieved within 6 min (compared with 30 min in HPLC) with acceptable resolution and improved sensitivity (0.005-0.02 μg/mL vs. 0.04 μg/mL). The proposed method was also applied to pharmacokinetic research: accelerated solvent extraction (ASE) was used to improve the extraction efficiency, which prepared extract much faster and more pure than conventional methods. As the pharmacokinetic parameters indicated, the monolithic capillary electro-chromatography method was efficient, sensitive, specific, and durable, guaranteeing its utility for the determination of multiple structure-related compounds in rat plasma. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Towards point of care testing for C. difficile infection by volatile profiling, using the combination of a short multi-capillary gas chromatography column with metal oxide sensor detection

    International Nuclear Information System (INIS)

    McGuire, N D; Ewen, R J; De Lacy Costello, B; Garner, C E; Vaughan, K; Ratcliffe, N M; Probert, C S J

    2014-01-01

    Rapid volatile profiling of stool sample headspace was achieved using a combination of short multi-capillary chromatography column (SMCC), highly sensitive heated metal oxide semiconductor sensor and artificial neural network software. For direct analysis of biological samples this prototype offers alternatives to conventional gas chromatography (GC) detectors and electronic nose technology. The performance was compared to an identical instrument incorporating a long single capillary column (LSCC). The ability of the prototypes to separate complex mixtures was assessed using gas standards and homogenized in house ‘standard’ stool samples, with both capable of detecting more than 24 peaks per sample. The elution time was considerably faster with the SMCC resulting in a run time of 10 min compared to 30 min for the LSCC. The diagnostic potential of the prototypes was assessed using 50 C. difficile positive and 50 negative samples. The prototypes demonstrated similar capability of discriminating between positive and negative samples with sensitivity and specificity of 85% and 80% respectively. C. difficile is an important cause of hospital acquired diarrhoea, with significant morbidity and mortality around the world. A device capable of rapidly diagnosing the disease at the point of care would reduce cases, deaths and financial burden. (paper)

  6. Glasses

    DEFF Research Database (Denmark)

    Dyre, Jeppe

    2004-01-01

    The temperature dependence of the viscosity of most glassforming liquids is known to depart significantly from the classical Arrhenius behaviour of simple fluids. The discovery of an unexpected correlation between the extent of this departure and the Poisson ratio of the resulting glass could lead...... to new understanding of glass ageing and viscous liquid dynamics....

  7. Preparation of open tubular capillary columns by in situ ring-opening polymerization and their applications in cLC-MS/MS analysis of tryptic digest.

    Science.gov (United States)

    Wang, Hongwei; Yao, Yating; Li, Ya; Ma, Shujuan; Peng, Xiaojun; Ou, Junjie; Ye, Mingliang

    2017-08-01

    An open tubular (OT) column (25 μm i.d.) was prepared by in situ ring-opening polymerization of octaglycidyldimethylsilyl polyhedral oligomeric silsesquioxanes (POSS-epoxy) with 4-aminophenyl disulfide (APDS) in a binary porogenic system of ethanol/H 2 O. It was found that porogenic composition played an important role in the formation of OT stationary phases. The ratio of ethanol/H 2 O at 6/1 (v/v) would lead to the fabrication of hybrid monoliths, while the ratio of ethanol/H 2 O at 13/1 (v/v) would result in the synthesis of OT phases. In addition, the effects of precursor content and reaction duration on the thickness of OT stationary phases were investigated. Either lower precursor content or shorter reaction duration would produce thinner layer of OT column. The repeatability of OT columns was evaluated through relative standard deviation (RSD%) with benzene as the analyte. The run-to-run, column-to-column and batch-to-batch repeatabilities were 1.7%, 4.8% and 5.6%, respectively, exhibiting satisfactory repeatability of the OT column. Then tryptic digest of mouse liver proteins was used to evaluate the performance of the resulting OT columns (25 μm i.d. × 2.5 m in length) by cLC-MS/MS analysis, demonstrating their potential in proteome analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Capillary gas-solid chromatography

    International Nuclear Information System (INIS)

    Berezkin, V.G.

    1996-01-01

    Modern state of gas adsorption chromatography in open capillary columns has been analyzed. The history of the method development and its role in gas chromatography, ways to construct open adsorptional capillary columns, foundations of the theory of retention and washing of chromatographic regions in gas adsorption capillary columns have been considered. The fields is extensively and for analyzing volatile compounds of different isotopic composition, inorganic and organic gases, volatile organic polar compounds, aqueous solutions of organic compounds. Separation of nuclear-spin isomers and isotopes of hydrogen is the first illustrative example of practical application of the adsorption capillary chromatography. It is shown that duration of protium and deuterium nuclear isomers may be reduced if the column temperature is brought to 47 K

  9. Conventional and narrow bore short capillary columns with cyclodextrin derivatives as chiral selectors to speed-up enantioselective gas chromatography and enantioselective gas chromatography-mass spectrometry analyses.

    Science.gov (United States)

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

    2008-11-28

    The analysis of complex real-world samples of vegetable origin requires rapid and accurate routine methods, enabling laboratories to increase sample throughput and productivity while reducing analysis costs. This study examines shortening enantioselective-GC (ES-GC) analysis time following the approaches used in fast GC. ES-GC separations are due to a weak enantiomer-CD host-guest interaction and the separation is thermodynamically driven and strongly influenced by temperature. As a consequence, fast temperature rates can interfere with enantiomeric discrimination; thus the use of short and/or narrow bore columns is a possible approach to speeding-up ES-GC analyses. The performance of ES-GC with a conventional inner diameter (I.D.) column (25 m length x 0.25 mm I.D., 0.15 microm and 0.25 microm d(f)) coated with 30% of 2,3-di-O-ethyl-6-O-tert-butyldimethylsilyl-beta-cyclodextrin in PS-086 is compared to those of conventional I.D. short column (5m length x 0.25 mm I.D., 0.15 microm d(f)) and of different length narrow bore columns (1, 2, 5 and 10 m long x 0.10 mm I.D., 0.10 microm d(f)) in analysing racemate standards of pesticides and in the flavour and fragrance field and real-world-samples. Short conventional I.D. columns gave shorter analysis time and comparable or lower resolutions with the racemate standards, depending mainly on analyte volatility. Narrow-bore columns were tested under different analysis conditions; they provided shorter analysis time and resolutions comparable to those of conventional I.D. ES columns. The narrow-bore columns offering the most effective compromise between separation efficiency and analysis time are the 5 and 2m columns; in combination with mass spectrometry as detector, applied to lavender and bergamot essential oil analyses, these reduced analysis time by a factor of at least three while separation of chiral markers remained unaltered.

  10. Arsenic Removal from Aqueous Solution Using Pure and Metal-Doped Titania Nanoparticles Coated on Glass Beads: Adsorption and Column Studies

    Directory of Open Access Journals (Sweden)

    M. Ihsan Danish

    2013-01-01

    Full Text Available Nanosized metal oxide, Titania, provides high surface area and specific affinity for the adsorption of heavy metals, including arsenic (As, which is posing a great threat to the world population due to its carcinogenic nature. In this study, As(III adsorption was studied on pure and metal- (Ag- and Fe- doped Titania nanoparticles. The nanoparticles were synthesized by liquid impregnation method with some modifications, with crystallite size in the range of 30 to 40 nm. Band gap analysis, using Kubelka-Munk function showed a shift of absorption band from UV to visible region for the metal-doped Titania. Effect of operational parameters like dose of nanoparticles, initial As(III concentration, and pH was evaluated at 25°C. The data obtained gave a good fit with Langmuir and Freundlich isotherms and the adsorption was found to conform to pseudo-second-order kinetics. In batch studies, over 90% of arsenic removal was observed for both types of metal-doped Titania nanoparticles from a solution containing up to 2 ppm of the heavy metal. Fixed bed columns of nanoparticles, coated on glass beads, were used for As(III removal under different operating conditions. Thomas and Yoon-Nelson models were applied to predict the breakthrough curves and to find the characteristic column parameters useful for process design. The columns were regenerated using 10% NaOH solution.

  11. Preliminary application of tapered glass capillary microbeam in MeV-PIXE mapping of longan leaf for elemental concentration distribution analysis

    Science.gov (United States)

    Natyanun, S.; Unai, S.; Yu, L. D.; Tippawan, U.; Pussadee, N.

    2017-09-01

    This study was aimed at understanding elemental concentration distribution in local longan leaf for how the plant was affected by the environment or agricultural operation. The analysis applied the MeV-microbeam particle induced X-ray emission (PIXE) mapping technique using a home-developed tapered glass capillary microbeam system at Chiang Mai University. The microbeam was 2-MeV proton beam in 130 µm in diameter. The studying interest was in the difference in the elemental concentrations distributed between the leaf midrib and lamina areas. The micro proton beam analyzed the leaf sample across the leaf midrib edge to the leaf lamina area for total 9 data requisition spots. The resulting data were colored to form a 1D-map of the elemental concentration distribution. Seven dominant elements, Al, S, Cl, K, Ca, Sc and Fe, were identified, the first six of which were found having higher concentrations in the midrib area than in the lamina area, while the Fe concentration was in an opposite trend to that of the others.

  12. X-ray focusing using capillary arrays

    International Nuclear Information System (INIS)

    Nugent, K.A.; Chapman, H.N.

    1990-01-01

    A new form of X-ray focusing device based on glass capillary arrays is presented. Theoretical and experimental results for array of circular capillaries and theoretical and computational results for square hole capillaries are given. It is envisaged that devices such as these will find wide applications in X-ray optics as achromatic condensers and collimators. 3 refs., 4 figs

  13. Chip-based molecularly imprinted monolithic capillary array columns coated GO/SiO2 for selective extraction and sensitive determination of rhodamine B in chili powder.

    Science.gov (United States)

    Zhai, Haiyun; Huang, Lu; Chen, Zuanguang; Su, Zihao; Yuan, Kaisong; Liang, Guohuan; Pan, Yufang

    2017-01-01

    A novel solid-phase extraction chip embedded with array columns of molecularly imprinted polymer-coated silanized graphene oxide (GO/SiO2-MISPE) was established to detect trace rhodamine B (RB) in chili powder. GO/SiO2-MISPE monolithic columns for RB detection were prepared by optimizing the supporting substrate, template, and polymerizing monomer under mild water bath conditions. Adsorption capacity and specificity, which are critical properties for the application of the GO/SiO2-MISPE monolithic column, were investigated. GO/SiO2-MIP was examined by scanning electron microscopy (SEM) and Fourier transform-infrared spectroscopy. The recovery and the intraday and interday relative standard deviations for RB ranged from 83.7% to 88.4% and 2.5% to 4.0% and the enrichment factors were higher than 110-fold. The chip-based array columns effectively eliminated impurities in chili powder, indicating that the chip-based GO/SiO2-MISPE method was reliable for RB detection in food samples using high-performance liquid chromatography. Accordingly, this method has direct applications for monitoring potentially harmful dyes in processed food. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Preparation of hydrophilic monolithic capillary column by in situ photo-polymerization of N-vinyl-2-pyrrolidinone and acrylamide for highly selective and sensitive enrichment of N-linked glycopeptides.

    Science.gov (United States)

    Jiang, Hao; Yuan, Huiming; Qu, Yanyan; Liang, Yu; Jiang, Bo; Wu, Qi; Deng, Nan; Liang, Zhen; Zhang, Lihua; Zhang, Yukui

    2016-01-01

    In this study, a novel kind of amide functionalized hydrophilic monolith was synthesized by the in situ photo-polymerization of N-vinyl-2-pyrrolidinone (NVP), acrylamide (AM), and N, N'-methylenebisacrylamide (MBA) in a UV transparent capillary, and successfully applied for hydrophilic interaction chromatography (HILIC) based enrichment of N-linked glycopeptides. With 2 μg of the tryptic digests of IgG as the sample, after enrichment, 18 glycopeptides could be identified by MALDI-TOF/TOF MS analysis. Furthermore, with the mixture of BSA and IgG digests (10,000:1, m/m) as the sample, 6 N-linked glycopeptides were unambiguously identified after enrichment, indicating the high selectivity and good specificity of such material. Moreover, such a monolithic capillary column was also applied for the N-glycosylation sites profiling of 6 μg protein digests from HeLa cells and 1 μL human serum. In total, 530 and 262 unique N-glycosylated peptides were identified, respectively, corresponding to 282 and 124N-glycoproteins, demonstrating its great potential for the large scale glycoproteomics analysis. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Enantioselective column coupled electrophoresis employing large bore capillaries hyphenated with tandem mass spectrometry for ultra-trace determination of chiral compounds in complex real samples.

    Science.gov (United States)

    Piešťanský, Juraj; Maráková, Katarína; Kovaľ, Marián; Havránek, Emil; Mikuš, Peter

    2015-12-01

    A new multidimensional analytical approach for the ultra-trace determination of target chiral compounds in unpretreated complex real samples was developed in this work. The proposed analytical system provided high orthogonality due to on-line combination of three different methods (separation mechanisms), i.e. (1) isotachophoresis (ITP), (2) chiral capillary zone electrophoresis (chiral CZE), and (3) triple quadrupole mass spectrometry (QqQ MS). The ITP step, performed in a large bore capillary (800 μm), was utilized for the effective sample pretreatment (preconcentration and matrix clean-up) in a large injection volume (1-10 μL) enabling to obtain as low as ca. 80 pg/mL limits of detection for the target enantiomers in urine matrices. In the chiral CZE step, the different chiral selectors (neutral, ionizable, and permanently charged cyclodextrins) and buffer systems were tested in terms of enantioselectivity and influence on the MS detection response. The performance parameters of the optimized ITP - chiral CZE-QqQ MS method were evaluated according to the FDA guidance for bioanalytical method validation. Successful validation and application (enantioselective monitoring of renally eliminated pheniramine and its metabolite in human urine) highlighted great potential of this chiral approach in advanced enantioselective biomedical applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Microencapsulation of Clostridium difficile specific bacteriophages using microfluidic glass capillary devices for colon delivery using pH triggered release.

    Directory of Open Access Journals (Sweden)

    Gurinder K Vinner

    Full Text Available The prevalence of pathogenic bacteria acquiring multidrug antibiotic resistance is a global health threat to mankind. This has motivated a renewed interest in developing alternatives to conventional antibiotics including bacteriophages (viruses as therapeutic agents. The bacterium Clostridium difficile causes colon infection and is particularly difficult to treat with existing antibiotics; phage therapy may offer a viable alternative. The punitive environment within the gastrointestinal tract can inactivate orally delivered phages. C. difficile specific bacteriophage, myovirus CDKM9 was encapsulated in a pH responsive polymer (Eudragit® S100 with and without alginate using a flow focussing glass microcapillary device. Highly monodispersed core-shell microparticles containing phages trapped within the particle core were produced by in situ polymer curing using 4-aminobenzoic acid dissolved in the oil phase. The size of the generated microparticles could be precisely controlled in the range 80 μm to 160 μm through design of the microfluidic device geometry and by varying flow rates of the dispersed and continuous phase. In contrast to free 'naked' phages, those encapsulated within the microparticles could withstand a 3 h exposure to simulated gastric fluid at pH 2 and then underwent a subsequent pH triggered burst release at pH 7. The significance of our research is in demonstrating that C. difficile specific phage can be formulated and encapsulated in highly uniform pH responsive microparticles using a microfluidic system. The microparticles were shown to afford significant protection to the encapsulated phage upon prolonged exposure to an acid solution mimicking the human stomach environment. Phage encapsulation and subsequent release kinetics revealed that the microparticles prepared using Eudragit® S100 formulations possess pH responsive characteristics with phage release triggered in an intestinal pH range suitable for therapeutic

  17. Evaluation of Packed Distillation Columns I - Atmospheric Pressure

    National Research Council Canada - National Science Library

    Reynolds, Thaine

    1951-01-01

    .... Four column-packing combinations of the glass columns and four column-packing combinations of the steel columns were investigated at atmospheric pressure using a test mixture of methylcyclohexane...

  18. The analysis of semi-volatile and non-volatile petroleum hydrocarbons in a soil/sediment matrix by capillary column gas chromatography/flame ionization detection (GC/FID)

    International Nuclear Information System (INIS)

    George, J.E. III; Thoma, J.J.; Hastings, M.

    1990-01-01

    A comprehensive analysis for semi-volatile and non-volatile fractions of petroleum hydrocarbons can be achieved by a solvent extraction/concentration techniques that will effectively extract these high molecular weight fractions from a soil matrix. The prepared extract is then injected directly into a gas chromatograph equipped with a capillary column and flame ionization detector. This technique applies to the following types of commercially available petroleum hydrocarbons: Diesel Nos. 2,4,5, and 6, fuel oils and several grades of lubrication oil. The identification of a particular petroleum hydrocarbon is determined visually by comparison of the samples with known hydrocarbon standards. Accurate quantitation of the chromatograms is possible by using peak area summation and the presence of an internal standard. The practical quantitation limit for the method is 10 mg/Kg for most fuel types. This paper presents a method for determining the concentration of these fuel types in soil. Data will be presented only on 10W40 lubrication oil in terms of method validation, calibration, percent recovery, and method detection limits. A discussion of the quatitation techniques used will also be included

  19. Weight-controlled capillary viscometer

    Science.gov (United States)

    Digilov, Rafael M.; Reiner, M.

    2005-11-01

    The draining of a water column through a vertical discharge capillary tube is examined with the aid of a force sensor. The change of the mass of the liquid in the column with time is found to be not purely exponential as implied by Poiseuille's law. Using observed residuals associated with a kinetic energy correction, an approximate formula for the mass as a function of time is derived and excellent agreement with experimental data is attained. These results are verified by a viscosity test of distilled water at room temperature. A simple and inexpensive weight-controlled capillary viscometer is proposed that is especially suitable for undergraduate physics and chemistry laboratories.

  20. The use of laboratory sand, soil and crushed-glass filter columns for polishing domestic-strength synthetic wastewater that has undergone secondary treatment.

    Science.gov (United States)

    Healy, M G; Burke, P; Rodgers, M

    2010-10-01

    The aim of this study was to examine the performance of intermittently loaded, 150 mm-diameter stratified filter columns of 2 depths (0.65 and 0.375 m) comprising different media--sand, crushed glass and soil--in polishing the effluent from a laboratory horizontal flow biofilm reactor (HFBR) treating synthetic domestic-strength wastewater. The HFBR has been successfully used to remove organic carbon and ammonium-nitrogen (NH4-N) from domestic wastewater. In this treatment method, wastewater is allowed to flow over and back along a stack of polyvinyl chloride (PVC) sheets. Biofilms on the sheets reduce organic carbon, suspended matter, and nutrients in the wastewater, but to achieve the quality of a septic tank system, additional treatment is required. In all filters, at a hydraulic loading rate of 100 L m(-2) d(-1), 40-65% of chemical oxygen demand (COD) and practically 100% of total suspended solids (TSS) were removed, nitrification was complete, and bacterial numbers were reduced by over 80%, with best removals achieved in the soil filters (93%). Soil polishing filters with the depth of 0.65 m performed best in terms of organic carbon, total nitrogen (Tot-N) and bacterial removal. Data from this preliminary study are useful in the design of treatment systems to polish secondary wastewaters with similar water quality characteristics.

  1. Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory - Determination of Wastewater Compounds by Polystyrene-Divinylbenzene Solid-Phase Extraction and Capillary-Column Gas Chromatography/Mass Spectrometry

    Science.gov (United States)

    Zaugg, Steven D.; Smith, Steven G.; Schroeder, Michael P.; Barber, Larry B.; Burkhardt, Mark R.

    2002-01-01

    A method for the determination of 67 compounds typically found in domestic and industrial wastewater is described. The method was developed in response to increasing concern over the impact of endocrine-disrupting chemicals in wastewater on aquatic organisms. This method also may be useful for evaluating the impact of combined sanitary and storm-sewer overflow on the water quality of urban streams. The method focuses on the determination of compounds that are an indicator of wastewater or that have been chosen on the basis of their endocrine-disrupting potential or toxicity. These compounds include the alkylphenol ethoxylate nonionic surfactants and their degradates, food additives, fragrances, antioxidants, flame retardants, plasticizers, industrial solvents, disinfectants, fecal sterols, polycyclicaromatic hydrocarbons, and high-use domestic pesticides. Water samples are filtered to remove suspended particulate matter and then are extracted by vacuum through disposable solid-phase cartridges that contain polystyrene-divinylbenzene resin. Cartridges are dried with nitrogen gas, and then sorbed compounds are eluted with dichloromethane-diethyl ether (4:1) and determined by capillary-column gas chromatography/mass spectrometry. Recoveries in reagent-water samples fortified at 4 micrograms per liter averaged 74 percent ? 7 percent relative standard deviation for all method compounds. Initial method detection limits for single-component compounds (excluding hormones and sterols) averaged 0.15 microgram per liter. Samples are preserved by filtration, the addition of 60 grams NaCl, and storage at 4 degrees Celsius. The laboratory has established a sample-holding time (prior to sample extraction) of 14 days from the date of sample collection until a statistically accepted method can be used to determine the effectiveness of these sample-preservation procedures.

  2. Filling of charged cylindrical capillaries

    NARCIS (Netherlands)

    Das, Siddhartha; Chanda, Sourayon; Eijkel, J.C.T.; Tas, N.R.; Chakraborty, Suman; Mitra, Sushanta K.

    2014-01-01

    We provide an analytical model to describe the filling dynamics of horizontal cylindrical capillaries having charged walls. The presence of surface charge leads to two distinct effects: It leads to a retarding electrical force on the liquid column and also causes a reduced viscous drag force because

  3. Thermodynamics of Capillary Rise: Why Is the Meniscus Curved?

    Science.gov (United States)

    Henriksson, Ulf; Eriksson, Jan Christer

    2004-01-01

    The thermodynamics of capillary rise is explained as the gravitational elevation of the whole column of liquid caused by the positive connection between the liquid, and the solid wall of the capillary tube. The curvature of the meniscus is ascribed to the maintenance of a physiochemical balance throughout the gravitational column of liquid.

  4. Monoliths in capillary electrochromatography and capillary liquid chromatography in conjunction with mass spectrometry

    Czech Academy of Sciences Publication Activity Database

    Moravcová, Dana; Rantamäki, A. H.; Duša, Filip; Wiedmer, S. K.

    2016-01-01

    Roč. 37, 7-8 (2016), s. 880-912 ISSN 0173-0835 Institutional support: RVO:68081715 Keywords : capillary electrochromatography * capillary liquid chromatography * mass spec- trometry * monolithic columns Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.744, year: 2016

  5. Recent advances in column switching sample preparation in bioanalysis.

    Science.gov (United States)

    Kataoka, Hiroyuki; Saito, Keita

    2012-04-01

    Column switching techniques, using two or more stationary phase columns, are useful for trace enrichment and online automated sample preparation. Target fractions from the first column are transferred online to a second column with different properties for further separation. Column switching techniques can be used to determine the analytes in a complex matrix by direct sample injection or by simple sample treatment. Online column switching sample preparation is usually performed in combination with HPLC or capillary electrophoresis. SPE or turbulent flow chromatography using a cartridge column and in-tube solid-phase microextraction using a capillary column have been developed for convenient column switching sample preparation. Furthermore, various micro-/nano-sample preparation devices using new polymer-coating materials have been developed to improve extraction efficiency. This review describes current developments and future trends in novel column switching sample preparation in bioanalysis, focusing on innovative column switching techniques using new extraction devices and materials.

  6. Paramecium swimming in capillary tube

    Science.gov (United States)

    Jana, Saikat; Um, Soong Ho; Jung, Sunghwan

    2012-04-01

    Swimming organisms in their natural habitat need to navigate through a wide range of geometries and chemical environments. Interaction with boundaries in such situations is ubiquitous and can significantly modify the swimming characteristics of the organism when compared to ideal laboratory conditions. We study the different patterns of ciliary locomotion in glass capillaries of varying diameter and characterize the effect of the solid boundaries on the velocities of the organism. Experimental observations show that Paramecium executes helical trajectories that slowly transition to straight lines as the diameter of the capillary tubes decreases. We predict the swimming velocity in capillaries by modeling the system as a confined cylinder propagating longitudinal metachronal waves that create a finite pressure gradient. Comparing with experiments, we find that such pressure gradient considerations are necessary for modeling finite sized ciliary organisms in restrictive geometries.

  7. Meniscus formation in a capillary and the role of contact line friction.

    Science.gov (United States)

    Andrukh, Taras; Monaenkova, Daria; Rubin, Binyamin; Lee, Wah-Keat; Kornev, Konstantin G

    2014-01-28

    We studied spontaneous formation of an internal meniscus by dipping glass capillaries of 25 μm to 350 μm radii into low volatile hexadecane and tributyl phosphate. X-ray phase contrast and high speed optical microscopy imaging were employed. We showed that the meniscus completes its formation when the liquid column is still shorter than the capillary radius. After that, the meniscus travels about ten capillary radii at a constant velocity. We demonstrated that the experimental observations can be explained by introducing a friction force linearly proportional to the meniscus velocity with a friction coefficient depending on the air/liquid/solid triplet. It was demonstrated that the friction coefficient does not depend on the capillary radius. Numerical solution of the force balance equation revealed four different uptake regimes that can be specified in a phase portrait. This phase portrait was found to be in good agreement with the experimental results and can be used as a guide for the design of thin porous absorbers.

  8. Use of disposable open tubular ion exchange pre-columns for in-line clean-up of serum and plasma samples prior to capillary electrophoretic analysis of inorganic cations

    Czech Academy of Sciences Publication Activity Database

    Kiplagat, I.K.; Doan, T.K.O.; Kubáň, Pavel; Kubáň, P.; Boček, Petr

    2011-01-01

    Roč. 1218, č. 6 (2011), s. 856-859 ISSN 0021-9673 R&D Projects: GA ČR GAP206/10/1219 Institutional research plan: CEZ:AV0Z40310501 Keywords : sample treatment * capillary electrophoresis * biological samples Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.531, year: 2011

  9. Real-time monitoring of extracellular l-glutamate levels released by high-frequency stimulation at region CA1 of hippocampal slices with a glass capillary-based l-glutamate sensor

    Directory of Open Access Journals (Sweden)

    Yuki Ikegami

    2014-12-01

    Full Text Available Real-time monitoring of l-glutamate released by high-frequency stimulation in region CA1 of mouse hippocampal slices was performed with a glass capillary-based sensor, in combination with the recoding of excitatory postsynaptic potentials (fEPSPs. A method for extracting l-glutamate currents from the recorded ones was described and applied for determining the level of extracellular l-glutamate released by 100 Hz stimulation. Recording of an l-glutamate current with a current sampling interval of 1 Hz was found to be useful for acquiring a Faradaic current that reflects l-glutamate level released by the high-frequency stimulation of 7 trains, each 20 stimuli at 100 Hz and inter-train interval of 3 s. The l-glutamate level was obtained as 15 ± 6 μM (n = 8 for the persistent enhancement of fEPSPs, i.e., the induction of long-term potentiation (LTP, and 3 ± 1 μM (n = 5 for the case of no LTP induction. Based on these observations, the level of the extracellular l-glutamate was shown to play a crucial role in the induction of LTP.

  10. Annular pulse column development studies

    International Nuclear Information System (INIS)

    Benedict, G.E.

    1980-01-01

    The capacity of critically safe cylindrical pulse columns limits the size of nuclear fuel solvent extraction plants because of the limited cross-sectional area of plutonium, U-235, or U-233 processing columns. Thus, there is a need to increase the cross-sectional area of these columns. This can be accomplished through the use of a column having an annular cross section. The preliminary testing of a pilot-plant-scale annular column has been completed and is reported herein. The column is made from 152.4-mm (6-in.) glass pipe sections with an 89-mm (3.5-in.) o.d. internal tube, giving an annular width of 32-mm (1.25-in.). Louver plates are used to swirl the column contents to prevent channeling of the phases. The data from this testing indicate that this approach can successfully provide larger-cross-section critically safe pulse columns. While the capacity is only 70% of that of a cylindrical column of similar cross section, the efficiency is almost identical to that of a cylindrical column. No evidence was seen of any non-uniform pulsing action from one side of the column to the other

  11. Preparation of a poly(3'-azido-3'-deoxythymidine-co-propargyl methacrylate-co-pentaerythritol triacrylate) monolithic column by in situ polymerization and a click reaction for capillary liquid chromatography of small molecules and proteins.

    Science.gov (United States)

    Lin, Zian; Yu, Ruifang; Hu, Wenli; Zheng, Jiangnan; Tong, Ping; Zhao, Hongzhi; Cai, Zongwei

    2015-07-07

    Combining free radical polymerization with click chemistry via a copper-mediated azide/alkyne cycloaddition (CuAAC) reaction in a "one-pot" process, a facile approach was developed for the preparation of a poly(3'-azido-3'-deoxythymidine-co-propargyl methacrylate-co-pentaerythritol triacrylate) (AZT-co-PMA-co-PETA) monolithic column. The resulting poly(AZT-co-PMA-co-PETA) monolith showed a relatively homogeneous monolithic structure, good permeability and mechanical stability. Different ratios of monomers and porogens were used for optimizing the properties of a monolithic column. A series of alkylbenzenes, amides, anilines, and benzoic acids were used to evaluate the chromatographic properties of the polymer monolith in terms of hydrophobic, hydrophilic and cation-exchange interactions, and the results showed that the poly(AZT-co-PMA-co-PETA) monolith exhibited more flexible adjustment in chromatographic selectivity than that of the parent poly(PMA-co-PETA) and AZT-modified poly(PMA-co-PETA) monoliths. Column efficiencies for toluene, DMF, and formamide with 35,000-48,000 theoretical plates per m could be obtained at a linear velocity of 0.17 mm s(-1). The run-to-run, column-to-column, and batch-to-batch repeatabilities of the retention factors were less than 4.2%. In addition, the proposed monolith was also applied to efficient separation of sulfonamides, nucleobases and nucleosides, anesthetics and proteins for demonstrating its potential.

  12. Development of a new green non-dispersive ionic liquid microextraction method in a narrow glass column for determination of cadmium prior to couple with graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Naeemullah, E-mail: naeemullah433@yahoo.com [Gaziosmanpaşa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Kazi, Tasneem Gul [National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Tuzen, Mustafa [Gaziosmanpaşa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Shah, Faheem; Afridi, Hassan Imran [National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Citak, Demirhan [Gaziosmanpaşa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey)

    2014-02-17

    Graphical abstract: -- Highlights: •A novel and rapid non-dispersive ionic liquid based microextractions. •We used a long narrow glass column to provide more contact area between two media (aqueous and extractive). •APDC using as complexing agent and analyzed by GFAAS. •Introduced a novel approach that reduced solvent consumption, effort, time. •It was applied for determination of understudy analytes in real water sample. -- Abstract: Easy and innovative non-dispersive ionic liquid based microextraction (NDILME) has been developed for preconcentration of trace level of cadmium (Cd) in aqueous real surface water samples prior to couple with graphite furnace atomic absorption spectrometry (GFAAS). A 200 cm long narrow glass column containing aqueous solution of standard/sample was used to increase phase transfer ratio by providing more contact area between two medium (aqueous and extractive), which drastically improve the recoveries of labile hydrophobic chelate of Cd ammonium pyrrolidinedithiocarbamate (APDC), into ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate [C{sub 4}mim][PF{sub 6}]. Different aspect of the desire method have been investigated and optimized. Under the optimized key experimental variables, limit of detection (LOD) and enhancement factor (EF) were achieved to be 0.5 ng L{sup −1} and 150, respectively. Reliability of the model method was checked by relative standard deviation (%RSD), which was found to be < 5%. Validity and accuracy of the developed method was checked by analysis of certified reference water samples (SLRS-4 Riverine water) using standard addition method. Application of the model method was productively performed by analysis of Cd in real surface water samples (tap and sea)

  13. Flow rate control in pressure-programmed capillary supercritical fluid chromatography

    NARCIS (Netherlands)

    Janssen, J.G.M.; Rijks, J.A.; Cramers, C.A.M.G.

    1990-01-01

    A versatile and simple system is described that allows variation of the column flow rate in open-tubular capillary supercritical fluid chromatography using both on-column and postcolumn detection. The system is based on column-effluent splitting in a low-dead-volume T piece at the column exit just

  14. Analytical biotechnology: Capillary electrophoresis and chromatography

    International Nuclear Information System (INIS)

    Horvath, C.; Nikelly, J.G.

    1990-01-01

    The papers describe the separation, characterization, and equipment required for the electrophoresis or chromatography of cyclic nucleotides, pharmaceuticals, therapeutic proteins, recombinant DNA products, pheromones, peptides, and other biological materials. One paper, On-column radioisotope detection for capillary electrophoresis, has been indexed separately for inclusion on the data base

  15. Anomalous capillary flow of coal tar pitches

    Energy Technology Data Exchange (ETDEWEB)

    Saint Romain, J.L.; Lahaye, J.; Ehrburger, P.; Couderc, P.

    1986-06-01

    Capillary flow of liquid coal tar pitch into a coke bed was studied. Anomalies in the flow could not be attributed to a plugging effect for mesophase content lower than 20 wt%. The flow behaviour of small pitch droplets can be correlated with the change in physicochemical properties, as measured by the glass transition temperature, on penetration into the coke bed. 4 references.

  16. Analysis of lipoproteins by capillary zone electrophoresis in microfluidic devices: Assay development and surface roughness measurements

    NARCIS (Netherlands)

    Weiller, Bruce H.; Ceriotti, Laura; Shibata, Takayuki; Rein, Dietrich; Roberts, Matthew A.; Lichtenberg, Jan; German, J. Bruce; De Rooij, Nico F.; Verpoorte, Elisabeth

    2002-01-01

    The development of a new assay for lipoproteins by capillary electrophoresis in fused-silica capillaries and in glass microdevices is described in this paper. The separation of low-density (LDL) and high-density (HDL) lipoproteins by capillary zone electrophoresis is demonstrated in fused-silica

  17. Capillary detectors for high resolution tracking

    International Nuclear Information System (INIS)

    Annis, P.; Bay, A.; Bonekaemper, D.; Buontempo, S.; Ereditato, A.; Fabre, J.P.; Fiorillo, G.; Frekers, D.; Frenkel, A.; Galeazzi, F.; Garufi, F.; Goldberg, J.; Golovkin, S.; Hoepfner, K.; Konijn, J.; Kozarenko, E.; Kreslo, I.; Liberti, B.; Martellotti, G.; Medvedkov, A.; Mommaert, C.; Panman, J.; Penso, G.; Petukhov, Yu.; Rondeshagen, D.; Tyukov, V.; Vasilchenko, V.; Vilain, P.; Vischers, J.L.; Wilquet, G.; Winter, K.; Wolff, T.; Wong, H.

    1997-01-01

    We present a new tracking device based on glass capillary bundles or layers filled with highly purified liquid scintillator and read out at one end by means of image intensifiers and CCD devices. A large-volume prototype consisting of 5 x 10 5 capillaries with a diameter of 20 μm and a length of 180 cm and read out by a megapixel CCD has been tested with muon and neutrino beams at CERN. With this prototype a two track resolution of 33 μm was achieved with passing through muons. Images of neutrino interactions in a capillary bundle have also been acquired and analysed. Read-out chains based on electron bombarded CCD (EBCCD) and image pipeline devices are also investigated. Preliminary results obtained with a capillary bundle read out by an EBCCD are presented. (orig.)

  18. Capillary detectors for high resolution tracking

    CERN Document Server

    Annis, P

    1997-01-01

    We present a new tracking device based on glass capillary bundles or layers filled with highly purified liquid scintillator and read out at one end by means of image intensifiers and CCD devices. A large-volume prototype consisting of 5 × 105 capillaries with a diameter of 20 μm and a length of 180 cm and read out by a megapixel CCD has been tested with muon and neutrino beams at CERN. With this prototype a two track resolution of 33 μm was achieved with passing through muons. Images of neutrino interactions in a capillary bundle have also been acquired and analysed. Read-out chains based on Electron Bombarded CCD (EBCCD) and image pipeline devices are also investigated. Preliminary results obtained with a capillary bundle read out by an EBCCD are presented.

  19. Temperature fields occurring in dielectric capillaries for the transport of of ion beams

    International Nuclear Information System (INIS)

    Urbanovich, A.I.

    2012-01-01

    This paper presents the results of computing the temperature fields occurring in dielectric capillaries of glass for the transport of accelerated charged particles. It is shown that on the transport of ion beams with a power of several watts the capillary is heated intensively, whereas heat stresses may approach the lower bound associated with a real strength of glass. (authors)

  20. Capillary array electrophoresis using laser-excited confocal fluorescence detection

    Energy Technology Data Exchange (ETDEWEB)

    Huang, X.C.; Quesada, M.A.; Mathies, R.A. [Univ. of California, Berkeley, CA (United States)

    1992-04-15

    Capillary electrophoresis (CE) has found widespread application in analytical and biomedical research, and the scope and sophistication of CE is still rapidly advancing. Gel-filled capillaries have been employed for the rapid separation and analysis of synthetic polynucleotides, DNA sequencing fragments, and DNA restriction fragments. Open-tube capillary electrophoresis has attained subattomole detection levels in amino acid separations 14 and proven its utility for the separation of proteins, viruses, and bacteria. Separation of the optical isomers of dansyl amino acids has also been successfully demonstrated. Micellar electrokinetic capillary chromatography, isoelectric focusing, and on-column derivatization can all be performed on CE columns, demonstrating the utility of capillary electrophoresis as an analytical and micropreparative tool. 29 refs., 6 figs., 1 tab.

  1. Characterization of polymer monolithic stationary phases for capillary HPLC

    Czech Academy of Sciences Publication Activity Database

    Moravcová, D.; Jandera, P.; Urban, J.; Planeta, Josef

    2003-01-01

    Roč. 26, č. 11 (2003), s. 1005-1016 ISSN 1615-9306 R&D Projects: GA ČR GA203/02/0023 Institutional research plan: CEZ:AV0Z4031919; CEZ:MSM 253100002 Keywords : monolithic column s * capillary HPLC * column testing Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.108, year: 2003

  2. Performing chemical reactions in virtual capillary of surface tension ...

    Indian Academy of Sciences (India)

    The flow paths were fabricated by making parallel lines using permanent marker pen ink or other polymer on glass surfaces. Two mirror image patterned glass plates were then sandwiched one on top of the other, separated by a thin gap - created using a spacer. The aqueous liquid moves between the surfaces by capillary ...

  3. PULSE COLUMN

    Science.gov (United States)

    Grimmett, E.S.

    1964-01-01

    This patent covers a continuous countercurrent liquidsolids contactor column having a number of contactor states each comprising a perforated plate, a layer of balls, and a downcomer tube; a liquid-pulsing piston; and a solids discharger formed of a conical section at the bottom of the column, and a tubular extension on the lowest downcomer terminating in the conical section. Between the conical section and the downcomer extension is formed a small annular opening, through which solids fall coming through the perforated plate of the lowest contactor stage. This annular opening is small enough that the pressure drop thereacross is greater than the pressure drop upward through the lowest contactor stage. (AEC)

  4. Modeling aerobic biodegradation in the capillary fringe.

    Science.gov (United States)

    Luo, Jian; Kurt, Zohre; Hou, Deyi; Spain, Jim C

    2015-02-03

    Vapor intrusion from volatile subsurface contaminants can be mitigated by aerobic biodegradation. Laboratory column studies with contaminant sources of chlorobenzene and a mixture of chlorobenzene, 1,2-dichlorobenzene, and 1,4-dichlorobenzene showed that contaminants were rapidly degraded in thin reactive zones with high biomass and low substrate concentrations in the vicinity of the capillary fringe. Such behavior was well characterized by a model that includes oxygen-, substrate-, and biomass-dependent biodegradation kinetics along with diffusive transport processes. An analytical solution was derived to provide theoretical support for the simplification of reaction kinetics and the approximation of reactive zone location and mass flux relationships at steady state. Results demonstrate the potential of aerobic natural attenuation in the capillary fringe for preventing contaminant migration in the unsaturated zone. The solution indicates that increasing contaminant mass flux into the column creates a thinner reactive zone and pushes it toward the oxygen boundary, resulting in a shorter distance to the oxygen source and a larger oxygen mass flux that balances the contaminant mass flux. As a consequence, the aerobic biodegradation can reduce high contaminant concentrations to low levels within the capillary fringe and unsaturated zone. The results are consistent with the observations of thin reactive layers at the interface in unsaturated zones. The model considers biomass while including biodegradation in the capillary fringe and unsaturated zone and clearly demonstrates that microbial communities capable of using the contaminants as electron donors may lead to instantaneous degradation kinetics in the capillary fringe and unsaturated zone.

  5. Dosages d'hydrocarbures dans l'eau et le sédiment marins par infrarouge et chromatographie gazeuse sur colonne capillaire Hydrocarbon Titration in Water and Marine Sediments by Infrared Analysis and Gas Chromatography in a Capillary Column

    Directory of Open Access Journals (Sweden)

    Morel G.

    2006-11-01

    Full Text Available Nous avons étudié l'évolution des hydrocarbures pétroliers dans un site confiné, celui de l'Aber-Benoît (Finistère, à la suite de l'accident du super-pétrolier Amoco-Cadiz en mars 1978. Pour ce faire, plusieurs méthodes ont été mises en oeuvre, et tout particulièrement la chromato-graphie gazeuse sur colonne capillaire : le protocole analytique est décrit pour l'eau et pour le sédiment, après optimisation des techniques de filtration, de préconcentration et de fractionnement préalables à la mesure. Il est possible de travailler sur des échantillons de deux litres d'eau de mer ou de cinquante grammes de sédiment, avec des seuils de détection du niveau de la partie par trillion (ppt dans l'eau et de la centaine de ppt dans le sédiment. The evolution of petroleum hydrocarbons was analyzed in a confined site, at Aber-Benoît in the Finistère department, following the accident of the supertanker Amoco Cadiz in March 1978. To do this, several methods were developed, including, in particular, capillary coulumn as chromatography. The analytical procedure is described for water and sediment after optimization of filtering, preconcentrating and fractionating techniques prior to measuring. Analyses can be made with two liters of seawater or fifty grams of sediment, with detection thresholds in parts per trillion (ppt in water and the hundredth of a ppt in sediment.

  6. Growth of metal-organic framework HKUST-1 in capillary using liquid-phase epitaxy for open-tubular capillary electrochromatography and capillary liquid chromatography.

    Science.gov (United States)

    Bao, Tao; Zhang, Juan; Zhang, Wenpeng; Chen, Zilin

    2015-02-13

    Much attention is being paid to applying metal-organic frameworks (MOFs) as stationary phases in chromatography because of their fascinating properties, such as large surface-to-volume ratios, high levels of porosity, and selective adsorption. HKUST-1 is one of the best-studied face-centered-cubic MOF containing nano-sized channels and side pockets for film growth. However, growth of HKUST-1 framework inside capillary column as stationary phase for capillary electrochromatography is a challenge work. In this work, we carry out the growth of HKUST-1 on the inner wall of capillary by using liquid-phase epitaxy process at room temperature. The fabricated HKUST-1@capillary can be successfully used for the separation of substituted benzene including methylbenzene, ethylbenzene, styrene, chlorobenzene, bromobenzene, o-dichlorobenzene, benzene series, phenolic acids, and benzoic acids derivates. High column efficiency of 1.5×10(5) N/m for methylbenzene was achieved. The formation of HKUST-1 grown in the capillary was confirmed and characterized by scanning electron microscopy images, Fourier transform infrared spectra and X-ray diffraction. The column showed long lifetime and excellent stability. The relative standard deviations for intra-day and inter-day repeatability of the HKUST-1@capillary were lower than 7%. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Chalcogenide glass hollow core microstructured optical fibers

    Directory of Open Access Journals (Sweden)

    Vladimir S. eShiryaev

    2015-03-01

    Full Text Available The recent developments on chalcogenide glass hollow core microstructured optical fibers (HC-MOFs are presented. The comparative analysis of simulated optical properties for chalcogenide HC-MOFs of negative-curvature with different size and number of capillaries is given. The technique for the manufacture of microstructured chalcogenide preforms, which includes the assembly of the substrate glass tube and 8-10 capillaries, is described. Further trends to improve the optical transmission in chalcogenide NCHCFs are considered.

  8. Multiple capillary biochemical analyzer

    Science.gov (United States)

    Dovichi, N.J.; Zhang, J.Z.

    1995-08-08

    A multiple capillary analyzer allows detection of light from multiple capillaries with a reduced number of interfaces through which light must pass in detecting light emitted from a sample being analyzed, using a modified sheath flow cuvette. A linear or rectangular array of capillaries is introduced into a rectangular flow chamber. Sheath fluid draws individual sample streams through the cuvette. The capillaries are closely and evenly spaced and held by a transparent retainer in a fixed position in relation to an optical detection system. Collimated sample excitation radiation is applied simultaneously across the ends of the capillaries in the retainer. Light emitted from the excited sample is detected by the optical detection system. The retainer is provided by a transparent chamber having inward slanting end walls. The capillaries are wedged into the chamber. One sideways dimension of the chamber is equal to the diameter of the capillaries and one end to end dimension varies from, at the top of the chamber, slightly greater than the sum of the diameters of the capillaries to, at the bottom of the chamber, slightly smaller than the sum of the diameters of the capillaries. The optical system utilizes optic fibers to deliver light to individual photodetectors, one for each capillary tube. A filter or wavelength division demultiplexer may be used for isolating fluorescence at particular bands. 21 figs.

  9. Capillary gel electrophoresis for rapid, high resolution DNA sequencing.

    OpenAIRE

    Swerdlow, H; Gesteland, R

    1990-01-01

    Capillary gel electrophoresis has been demonstrated for the separation and detection of DNA sequencing samples. Enzymatic dideoxy nucleotide chain termination was employed, using fluorescently tagged oligonucleotide primers and laser based on-column detection (limit of detection is 6,000 molecules per peak). Capillary gel separations were shown to be three times faster, with better resolution (2.4 x), and higher separation efficiency (5.4 x) than a conventional automated slab gel DNA sequenci...

  10. Method of analysis and quality-assurance practices for determination of pesticides in water by solid-phase extraction and capillary-column gas chromatography/mass spectrometry at the U.S. Geological Survey California District Organic Chemistry Laboratory, 1996-99

    Science.gov (United States)

    Crepeau, Kathryn L.; Baker, Lucian M.; Kuivila, Kathryn

    2000-01-01

    A method of analysis and quality-assurance practices were developed to study the fate and transport of pesticides in the San Francisco Bay-Estuary by the U.S. Geological Survey. Water samples were filtered to remove suspended-particulate matter and pumped through C-8 solid-phase extraction cartridges to extract the pesticides. The cartridges were dried with carbon dioxide and the pesticides were eluted with three cartridge volumes of hexane:diethyl ether (1:1) solution. The eluants were analyzed using capillary-column gas chromatography/mass spectrometry in full-scan mode. Method detection limits for pesticides ranged from 0.002 to 0.025 microgram per liter for 1-liter samples. Recoveries ranged from 44 to 140 percent for 25 pesticides in samples of organic-free reagent water and Sacramento-San Joaquin Delta and Suisun Bay water fortified at 0.05 and 0.50 microgram per liter. The estimated holding time for pesticides after extraction on C-8 solid-phase extraction cartridges ranged from 10 to 257 days.

  11. Field-portable Capillary Electrophoresis Instrument with Conductivity Detection

    International Nuclear Information System (INIS)

    Zhang, H F; Liu, X W; Wang, W; Wang, X L; Tian, L

    2006-01-01

    In this paper a novel capillary electrophoresis chip (CEC) is presented with integrated platinum electrodes and simplified conductivity detector. CEC is fabricated by the method of mechanical modification with probe on organic glass. Capillary electrophoresis chip can rapidly completed ion separation by simulation of concentration distribution and zone-broadening. Detection circuit is simple which can detect pA order current. This system has those advantages such as small volume, low power consumption and linearity, and well suit for field analysis

  12. Intramedullary capillary haemangioma.

    LENUS (Irish Health Repository)

    Kelleher, T

    2012-02-03

    Intramedullary capillary haemangioma is extremely rare and only four cases have been previously reported. We describe a further case, outlining the clinical, radiological, surgical and pathological features.

  13. Microwave discharges in capillary tubes

    International Nuclear Information System (INIS)

    Dervisevic, Emil

    1984-01-01

    This research thesis aims at being a contribution to the study of microwave discharge by a surface wave, and more precisely focusses on the discharge in capillary tubes filled with argon. The author first present theoretical models which describe, on the one hand, the propagation of the surface wave along the plasma column, and, on the other hand, longitudinal and radial profiles of the main discharge characteristics. The second part addresses the study of the influence of parameters (gas pressure and tube radius) on discharge operation and characteristics. Laws of similitude as well as empirical relationships between argon I and argon II emission line intensities, electron density, and electric field in the plasma have been established [fr

  14. High-Throughput Proteomics Using High Efficiency Multiple-Capillary Liquid Chromatography With On-Line High-Performance ESI FTICR Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Yufeng (BATTELLE (PACIFIC NW LAB)); Tolic, Nikola (BATTELLE (PACIFIC NW LAB)); Zhao, Rui (ASSOC WESTERN UNIVERSITY); Pasa Tolic, Ljiljana (BATTELLE (PACIFIC NW LAB)); Li, Lingjun (Illinois Univ Of-Urbana/Champa); Berger, Scott J.(ASSOC WESTERN UNIVERSITY); Harkewicz, Richard (BATTELLE (PACIFIC NW LAB)); Anderson, Gordon A.(BATTELLE (PACIFIC NW LAB)); Belov, Mikhail E.(BATTELLE (PACIFIC NW LAB)); Smith, Richard D.(BATTELLE (PACIFIC NW LAB))

    2000-12-01

    We report on the design and application of a high-efficiency multiple-capillary liquid chromatography (LC) system for high-throughput proteome analysis. The multiple-capillary LC system was operated at the pressure of 10,000 psi using commercial LC pumps to deliver the mobile phase and newly developed passive feedback valves to switch the mobile phase flow and introduce samples. The multiple-capillary LC system was composed of several serially connected dual-capillary column devices. The dual-capillary column approach was designed to eliminate the time delay for regeneration (or equilibrium) of the capillary column after its use under the mobile phase gradient condition (i.e. one capillary column was used in separation and the other was washed using mobile phase A). The serially connected dual-capillary columns and ESI sources were operated independently, and could be used for either''backup'' operation or with other mass spectrometer(s). This high-efficiency multiple-capillary LC system uses switching valves for all operations and is highly amenable to automation. The separations efficiency of dual-capillary column device, optimal capillary dimensions (column length and packed particle size), suitable mobile phases for electrospray, and the capillary re-generation were investigated. A high magnetic field (11.5 tesla) Fourier transform ion cyclotron resonance (FTICR) mass spectrometer was coupled on-line with this high-efficiency multiple-capillary LC system through an electrospray ionization source. The capillary LC provided a peak capacity of {approx}600, and the 2-D capillary LC-FTICR provided a combined resolving power of > 6 x 10 7 polypeptide isotopic distributions. For yeast cellular tryptic digests, > 100,000 polypeptides were typically detected, and {approx}1,000 proteins can be characterized in a single run.

  15. [Is the use of plastic capillary tubes justified for blood gases analysis?].

    Science.gov (United States)

    Daurès, Marie-Françoise; Bozonnat, Marie-Cécile; Cristol, Jean-Paul

    2011-01-01

    Some clinical units, such as neonatal or maternity units, preferentially use capillary tubes when analysing blood gases. Using glass tubes is delicate and nurses must recollect blood when breaking. In order to eliminate this problem, we tested flexible, plastic capillary tubes in both the above mentionned units and in our biochemistry laboratory. Each unit, where glass tubes were habitually used, tested 200 flexible, plastic capillary tubes. In addition, the nursing staffed filled out a questionnaire concerned tube usage. Both units clearly preferred using the flexible tubes. In the laboratory, results for blood gas analyses were compared between rigid glass and flexible plastic capillary tubes for 112 patients. Concordance tests did not showed significant differences between the two tube types, except for hematocrit and total haemoglobin. A questionnaire was also presented to the lab technician, who confirmed the easier usability of plastic capillary tubes.

  16. Integrated refractive index optical ring resonator detector for capillary electrophoresis.

    Science.gov (United States)

    Zhu, Hongying; White, Ian M; Suter, Jonathan D; Zourob, Mohammed; Fan, Xudong

    2007-02-01

    We developed a novel miniaturized and multiplexed, on-capillary, refractive index (RI) detector using liquid core optical ring resonators (LCORRs) for future development of capillary electrophoresis (CE) devices. The LCORR employs a glass capillary with a diameter of approximately 100 mum and a wall thickness of a few micrometers. The circular cross section of the capillary forms a ring resonator along which the light circulates in the form of the whispering gallery modes (WGMs). The WGM has an evanescent field extending into the capillary core and responds to the RI change due to the analyte conducted in the capillary, thus permitting label-free measurement. The resonating nature of the WGM enables repetitive light-analyte interaction, significantly enhancing the LCORR sensitivity. This LCORR architecture achieves dual use of the capillary as a sensor head and a CE fluidic channel, allowing for integrated, multiplexed, and noninvasive on-capillary detection at any location along the capillary. In this work, we used electro-osmotic flow and glycerol as a model system to demonstrate the fluid transport capability of the LCORRs. In addition, we performed flow speed measurement on the LCORR to demonstrate its flow analysis capability. Finally, using the LCORR's label-free sensing mechanism, we accurately deduced the analyte concentration in real time at a given point on the capillary. A sensitivity of 20 nm/RIU (refractive index units) was observed, leading to an RI detection limit of 10-6 RIU. The LCORR marries photonic technology with microfluidics and enables rapid on-capillary sample analysis and flow profile monitoring. The investigation in this regard will open a door to novel high-throughput CE devices and lab-on-a-chip sensors in the future.

  17. New type of capillary for use as ion beam collimator and air-vacuum interface

    Energy Technology Data Exchange (ETDEWEB)

    Stoytschew, V., E-mail: valostoytschew@hotmail.com [Ruđer Bošković Institute, Bijenicka Cesta 54, 10000 Zagreb (Croatia); Schulte-Borchers, M. [Laboratory of Ion Beam Physics, ETH Zurich, Otto-Stern-Weg 5, CH-8093 Zurich (Switzerland); Božičević Mihalića, Iva [Ruđer Bošković Institute, Bijenicka Cesta 54, 10000 Zagreb (Croatia); Perez, R.D. [FaMAF, Universidad Nacional de Córdoba, (5000) Ciudad Universitaria, Córdoba (Argentina)

    2016-08-01

    Glass capillaries offer a unique way to combine small diameter ion beam collimation with an air-vacuum interface for ambient pressure ion beam applications. Usually they have an opening diameter of a few microns, limiting the air inflow sufficiently to maintain stable conditions on the vacuum side. As the glass capillaries generally are quite thin and fragile, handling of the capillary in the experiment becomes difficult. They also introduce an X-ray background produced by the capillary wall material, which has to be shielded or subtracted from the data for Particle Induced X-ray Emission (PIXE) applications. To overcome both drawbacks, a new type of conical glass capillary has been developed. It has a higher wall thickness eliminating the low energy X-ray background produced by common capillaries and leading to a more robust lens. The results obtained in first tests show, that this new capillary is suitable for ion beam collimation and encourage further work on the capillary production process to provide thick wall capillaries with an outlet diameter in the single digit micro- or even nanometre range.

  18. Nasal Lobular Capillary Hemangioma

    Directory of Open Access Journals (Sweden)

    Prashant Patil

    2013-01-01

    Full Text Available Nasal lobular capillary hemangioma is a rare benign tumor of the paranasal sinuses. This lesion is believed to grow rapidly in size over time. The exact etiopathogenesis is still a dilemma. We discuss a case of nasal lobular capillary hemangioma presenting with a history of epistaxis. Contrast enhanced computed tomography of paranasal sinuses revealed an intensely enhancing soft-tissue mass in the left nasal cavity and left middle and inferior meati with no obvious bony remodeling or destruction. We present imaging and pathologic features of nasal lobular capillary hemangioma and differentiate it from other entities like nasal angiofibroma.

  19. Evaluation of CP sil 8 film thickness for the capillary GC analysis of methyl mercury

    DEFF Research Database (Denmark)

    Petersen, Jens Højslev; Drabæk, Iver

    1992-01-01

    Different commercially available CP-Sil 8 CB capillary columns have been tested with a mixed standard containing methyl mercury chloride, ethyl mercury chloride and a stable nonpolar chlorinated hydrocarbon. The aim of the study was to see whether the columns tested could be used without special...... available insert for on-column injections on wide bore columns, and a 5.35 mum thick stationary phase. It was concluded that this CP Sil 8 CB column gave good results although minor interactions between the organo-mercury compounds and the column could be seen....

  20. Application of a diode-array detector in capillary electrophoresis

    NARCIS (Netherlands)

    Beck, W.; Hoek, van R.; Engelhardt, H.

    1993-01-01

    In the last decade diode-array detection has proved to be extremely useful in high performance liquid chromatography in recording UV-visible spectra directly and on-line in the column effluent. In capillary electrophoresis (CE) only fast-scanning detectors with long scan times (up to 2 s) are

  1. Development of immobilized membrane-based affinity columns for use in the online characterization of membrane bound proteins and for targeted affinity isolations

    International Nuclear Information System (INIS)

    Moaddel, Ruin; Wainer, Irving W.

    2006-01-01

    Membranes obtained from cell lines that express or do not express a target membrane bound protein have been immobilized on a silica-based liquid chromatographic support or on the surface of an activated glass capillary. The resulting chromatographic columns have been placed in liquid chromatographic systems and used to characterize the target proteins and to identify small molecules that bind to the target. Membranes containing ligand gated ion channels, G-protein coupled receptors and drug transporters have been prepared and characterized. If a marker ligand has been identified for the target protein, frontal or zonal displacement chromatographic techniques can be used to determine binding affinities (K d values) and non-linear chromatography can be used to assess the association (k on ) and dissociation (k off ) rate constants and the thermodynamics of the binding process. Membrane-based affinity columns have been created using membranes from a cell line that does not express the target protein (control) and the same cell line that expresses the target protein (experimental) after genomic transfection. The resulting columns can be placed in a parallel chromatography system and the differential retention between the control and experimental columns can be used to identify small molecules and protein that bind to the target protein. These applications will be illustrated using columns created using cellular membranes containing nicotinic acetylcholine receptors and the drug transporter P-glycoprotein

  2. Development of immobilized membrane-based affinity columns for use in the online characterization of membrane bound proteins and for targeted affinity isolations

    Energy Technology Data Exchange (ETDEWEB)

    Moaddel, Ruin [Gerontology Research Center, National Institute on Aging, National Institutes of Health, 5600 Nathan Shock Drive, Baltimore, MD 21224-6825 (United States); Wainer, Irving W. [Gerontology Research Center, National Institute on Aging, National Institutes of Health, 5600 Nathan Shock Drive, Baltimore, MD 21224-6825 (United States)]. E-mail: Wainerir@grc.nia.nih.gov

    2006-03-30

    Membranes obtained from cell lines that express or do not express a target membrane bound protein have been immobilized on a silica-based liquid chromatographic support or on the surface of an activated glass capillary. The resulting chromatographic columns have been placed in liquid chromatographic systems and used to characterize the target proteins and to identify small molecules that bind to the target. Membranes containing ligand gated ion channels, G-protein coupled receptors and drug transporters have been prepared and characterized. If a marker ligand has been identified for the target protein, frontal or zonal displacement chromatographic techniques can be used to determine binding affinities (K {sub d} values) and non-linear chromatography can be used to assess the association (k {sub on}) and dissociation (k {sub off}) rate constants and the thermodynamics of the binding process. Membrane-based affinity columns have been created using membranes from a cell line that does not express the target protein (control) and the same cell line that expresses the target protein (experimental) after genomic transfection. The resulting columns can be placed in a parallel chromatography system and the differential retention between the control and experimental columns can be used to identify small molecules and protein that bind to the target protein. These applications will be illustrated using columns created using cellular membranes containing nicotinic acetylcholine receptors and the drug transporter P-glycoprotein.

  3. Modelling of microwave sustained capillary plasma columns at atmospheric pressure

    International Nuclear Information System (INIS)

    Pencheva, M; Petrova, Ts; Benova, E; Zhelyazkov, I

    2006-01-01

    In this work we present a model of argon microwave sustained discharge at high pressure (1 atm), which includes two self-consistently linked parts - electrodynamic and kinetic ones. The model is based on a steady-state Boltzmann equation in an effective field approximation coupled with a collisional-radiative model for high-pressure argon discharge numerically solved together with Maxwell's equation for an azimuthally symmetric TM surface wave and wave energy balance equation. It is applied for the purpose of theoretical description of the discharge in a stationary state. The phase diagram, the electron energy distribution function as well as the dependences of the electron and heavy particles densities and the mean input power per electron on the electron number density and wave number are presented

  4. Influence of roughness on capillary forces between hydrophilic surfaces

    NARCIS (Netherlands)

    van Zwol, P. J.; Palasantzas, G.; De Hosson, J. Th. M.

    Capillary forces have been measured by atomic force microscopy in the plate-sphere setup between gold, borosilicate glass, GeSbTe, titanium, and UV-irradiated amorphous titanium-dioxide surfaces. The force measurements were performed as a function contact time and surface roughness in the range

  5. Admittance Scanning for Whole Column Detection.

    Science.gov (United States)

    Stamos, Brian N; Dasgupta, Purnendu K; Ohira, Shin-Ichi

    2017-07-05

    Whole column detection (WCD) is as old as chromatography itself. WCD requires an ability to interrogate column contents from the outside. Other than the obvious case of optical detection through a transparent column, admittance (often termed contactless conductance) measurements can also sense changes in the column contents (especially ionic content) from the outside without galvanic contact with the solution. We propose here electromechanically scanned admittance imaging and apply this to open tubular (OT) chromatography. The detector scans across the column; the length resolution depends on the scanning velocity and the data acquisition frequency, ultimately limited by the physical step resolution (40 μm in the present setup). Precision equal to this step resolution was observed for locating an interface between two immiscible liquids inside a 21 μm capillary. Mechanically, the maximum scanning speed was 100 mm/s, but at 1 kHz sampling rate and a time constant of 25 ms, the highest practical scan speed (no peak distortion) was 28 mm/s. At scanning speeds of 0, 4, and 28 mm/s, the S/N for 180 pL (zone length of 1.9 mm in a 11 μm i.d. column) of 500 μM KCl injected into water was 6450, 3850, and 1500, respectively. To facilitate constant and reproducible contact with the column regardless of minor variations in outer diameter, a double quadrupole electrode system was developed. Columns of significant length (>1 m) can be readily scanned. We demonstrate its applicability with both OT and commercial packed columns and explore uniformity of retention along a column, increasing S/N by stopped-flow repeat scans, etc. as unique applications.

  6. Can positrons be guided by insulating capillaries?

    International Nuclear Information System (INIS)

    DuBois, R.D.; Toekesi, K.

    2011-01-01

    Complete text of publication follows. Investigations of guiding of few hundred eV antiparticles by macroscopic insulating capillaries have been described. Using subfemtoamp positron and electron beams, we demonstrated that a portion of the entering beams were transmitted and emerged in the direction of the capillary. We also demonstrated that the transmitted intensities decreased as the capillary tilt angle was increased (see Fig. 1). Both of these are indications of guiding. However, a comparison with transmitted photon data implies that the positron transmission may result from geometric factors associated with our diffuse beams and tapered capillary used in these studies. For electrons, the comparison indicates differences which could imply that even very low intensity beams can be guided. Measurements of the transmitted intensity as a function of charge entering the capillary were inconclusive as no major increases in the transmitted intensity were observed. 2D static simulations imply that our beam intensities, although extremely small with respect to previous guiding experiments, were capable of supplying sufficient charge for guiding to occur. Although not definitive, our study implies that sub-femtoamp beam intensities are sufficient to form charge patches and produce guiding. This may have been observed for electrons with the question remaining open for positrons. That guiding was not clearly seen may have been due to the capillary geometry used or it may indicate that although sufficient charge is being supplied, the surface and bulk resistivities of glass permit this charge to dissipate faster than it is formed. This aspect was not taken into consideration in our simulations but a crude estimate of the discharge rate implies that beam intensities on the order of pA, rather than fA as used here, may be required for guiding to occur in the capillaries used here. Additional studies are required to definitively answer the question as to whether antiparticles

  7. Ultra narrow bore thick film capillaries for microcolumn separations. Part 1. GC experiments

    NARCIS (Netherlands)

    Steenackers, D.; Sandra, P.J.F.; Sandra, P.; Devos, G.

    1993-01-01

    Ultra narrow bore (50 mum 1.0.) fused silica columns were statically coated with apolar stationary phases to obtain beta values ranging from 6.25 to 50 (filmthickness 2 to 0.25 mum). Performance of the 1 and 2 mum columns in Capillary Gas Chromatography (CGC) is highlighted.

  8. On-line Automated Sample Preparation-Capillary Gas Chromatography for the Analysis of Plasma Samples.

    NARCIS (Netherlands)

    Louter, A.J.H.; van der Wagt, R.A.C.A.; Brinkman, U.A.T.

    1995-01-01

    An automated sample preparation module, (the automated sample preparation with extraction columns, ASPEC), was interfaced with a capillary gas chromatograph (GC) by means of an on-column interface. The system was optimised for the determination of the antidepressant trazodone in plasma. The clean-up

  9. Reducing the Edge Chipping for Capillary End Face Grinding and Polishing

    Directory of Open Access Journals (Sweden)

    Hošek J.

    2013-05-01

    Full Text Available This paper presents results of glass capillary end face grinding and polishing by approach that reduces the edge chipping. Brittle materials have natural tendency for edge chipping what leads to beveling the sharp edges. Not beveled sharp edges on glass capillary are important for special applications like surface tension measurement of small liquid samples. We use common grinding and polishing process for capillary end face machining modified with gradual decreasing of grinding load based on the relation of the critical chipping load. Achieved surface roughness is measured using atomic force microscopy (AFM. Capillary inner edge quality is checked both with optical microscopes and electron microscope too. We achieved a non-chipped capillary inner edge with radius down to 100 nm.

  10. Evaluation of Carbon Nanotubes Functionalized Polydimethylsiloxane Based Coatings for In-Tube Solid Phase Microextraction Coupled to Capillary Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Neus Jornet-Martínez

    2015-08-01

    Full Text Available In the present work, the performance of carbon nanotubes (c-CNTs functionalized polydimethylsiloxane (PDMS based coatings as extractive phases for in-tube solid phase microextraction (IT-SPME coupled to Capillary LC (CapLC has been evaluated. Carboxylic-single walled carbon nanotubes (c-SWNTs and carboxylic-multi walled carbon nanotubes (c-MWNTs have been immobilized on the activated surface of PDMS capillary columns. The effect of different percentages of diphenyl groups in the PDMS extractive phase has also been evaluated. The extraction capability of the capillary columns has been tested for different organic pollutants, nitrogen heterocyclic compounds and polycyclic aromatic compounds (PAHs. The results indicated that the use of the c-CNTs-PDMS capillary columns improve pyriproxyfen and mainly PAH extraction. Triazines were better extracted by unmodified TRB-35 and modified c-CNTs-PDMSTRB-5. The results showed that the extraction capability of the c-CNT capillary columns depends not only on the polarity of the analytes (as it occurs with PDMS columns but also on the interactions that the analytes can establish with the immobilized c-CNTs on the PDMS columns. The extraction efficiency has been evaluated on the basis of the preconcentration rate that can be achieved, and, in this sense, the best c-CNTs-PDMS capillary column for each group of compounds can be proposed.

  11. Gas-Filled Capillary Model

    International Nuclear Information System (INIS)

    Steinhauer, L. C.; Kimura, W. D.

    2006-01-01

    We have developed a 1-D, quasi-steady-state numerical model for a gas-filled capillary discharge that is designed to aid in selecting the optimum capillary radius in order to guide a laser beam with the required intensity through the capillary. The model also includes the option for an external solenoid B-field around the capillary, which increases the depth of the parabolic density channel in the capillary, thereby allowing for propagation of smaller laser beam waists. The model has been used to select the parameters for gas-filled capillaries to be utilized during the Staged Electron Laser Acceleration -- Laser Wakefield (STELLA-LW) experiment

  12. Biomimetic Unidirectional Capillary Action

    Science.gov (United States)

    Rupert, Eric; Moran, Patrick; Dahl, Jason

    2017-11-01

    In arid environments animals require specialized adaptations to collect adequate water. The Texas horned lizard (P. cornutum) has superhydrophylic skin which draws water out of moist soil or directly from water sources. The water then makes its way into the lizard's unidirectional capillary system, made of overlapping scales, which serves to channel water to its mouth. Testing different channel geometries, repeated ``D'' shaped chambers as in Commans et al. (2015) and truncated isosceles triangle chambers, as found in P. cornutum, we show the ability to have passive, unidirectional, fluid transport. Tests were carried out with the capillaries in a horizontal configuration. While both capillary geometries produced the desired traits, the triangular chambers showed superior unidirectionality, with no observed back flow, while ``D'' chambers showed back flow under testing conditions. The chambers provided similar flow rates. These types of channel systems will find use in microfluidics, notably in medical, printing, and lab-on-chip applications.

  13. Capillary condenser/evaporator

    Science.gov (United States)

    Valenzuela, Javier A. (Inventor)

    2010-01-01

    A heat transfer device is disclosed for transferring heat to or from a fluid that is undergoing a phase change. The heat transfer device includes a liquid-vapor manifold in fluid communication with a capillary structure thermally connected to a heat transfer interface, all of which are disposed in a housing to contain the vapor. The liquid-vapor manifold transports liquid in a first direction and conducts vapor in a second, opposite direction. The manifold provides a distributed supply of fluid (vapor or liquid) over the surface of the capillary structure. In one embodiment, the manifold has a fractal structure including one or more layers, each layer having one or more conduits for transporting liquid and one or more openings for conducting vapor. Adjacent layers have an increasing number of openings with decreasing area, and an increasing number of conduits with decreasing cross-sectional area, moving in a direction toward the capillary structure.

  14. Bacterial surface layer proteins as a novel capillary coating material for capillary electrophoretic separations

    Energy Technology Data Exchange (ETDEWEB)

    Moreno-Gordaliza, Estefanía, E-mail: emorenog@ucm.es [Division of Analytical Biosciences, Leiden Academic Centre for Drug Research, Universiteit Leiden, Einsteinweg 55, 2300, RA, Leiden (Netherlands); Department of Analytical Chemistry, Faculty of Chemistry, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040, Madrid (Spain); Stigter, Edwin C.A. [Division of Analytical Biosciences, Leiden Academic Centre for Drug Research, Universiteit Leiden, Einsteinweg 55, 2300, RA, Leiden (Netherlands); Department of Molecular Cancer Research, Universitair Medisch Centrum Utrecht, Wilhelmina Kinder Ziekenhuis, Lundlaan 6, 3584, EA Utrecht (Netherlands); Lindenburg, Petrus W.; Hankemeier, Thomas [Division of Analytical Biosciences, Leiden Academic Centre for Drug Research, Universiteit Leiden, Einsteinweg 55, 2300, RA, Leiden (Netherlands)

    2016-06-07

    A novel concept for stable coating in capillary electrophoresis, based on recrystallization of surface layer proteins on hydrophobized fused silica capillaries, was demonstrated. Surface layer protein A (SlpA) from Lactobacillus acidophilus bacteria was extracted, purified and used for coating pre-silanized glass substrates presenting different surface wettabilities (either hydrophobic or hydrophilic). Contact angle determination on SlpA-coated hydrophobic silica slides showed that the surfaces turned to hydrophilic after coating (53 ± 5°), due to a protein monolayer formation by protein-surface hydrophobic interactions. Visualization by atomic force microscopy demonstrated the presence of a SlpA layer on methylated silica slides displaying a surface roughness of 0.44 ± 0.02 nm. Additionally, a protein layer was visualized by fluorescence microscopy in methylated silica capillaries coated with SlpA and fluorescein isothiocyanate-labeled. The SlpA-coating showed an outstanding stability, even after treatment with 20 mM NaOH (pH 12.3). The electroosmotic flow in coated capillaries showed a partial suppression at pH 7.50 (3.8 ± 0.5 10{sup −9} m{sup 2} V{sup −1} s{sup −1}) when compared with unmodified fused silica (5.9 ± 0.1 10{sup −8} m{sup 2} V{sup −1} s{sup −1}). To demonstrate the potential of this novel coating, the SlpA-coated capillaries were applied for the first time for electrophoretic separation, and proved to be very suitable for the isotachophoretic separation of lipoproteins in human serum. The separations showed a high degree of repeatability (absolute migration times with 1.1–1.8% coefficient-of-variation (CV) within a day) and 2–3% CV inter-capillary reproducibility. The capillaries were stable for more than 100 runs at pH 9.40, and showed to be an exceptional alternative for challenging electrophoretic separations at long-term use. - Highlights: • New coating using recrystallized surface-layer proteins on

  15. Capillary Rise: Validity of the Dynamic Contact Angle Models.

    Science.gov (United States)

    Wu, Pingkeng; Nikolov, Alex D; Wasan, Darsh T

    2017-08-15

    The classical Lucas-Washburn-Rideal (LWR) equation, using the equilibrium contact angle, predicts a faster capillary rise process than experiments in many cases. The major contributor to the faster prediction is believed to be the velocity dependent dynamic contact angle. In this work, we investigated the dynamic contact angle models for their ability to correct the dynamic contact angle effect in the capillary rise process. We conducted capillary rise experiments of various wetting liquids in borosilicate glass capillaries and compared the model predictions with our experimental data. The results show that the LWR equations modified by the molecular kinetic theory and hydrodynamic model provide good predictions on the capillary rise of all the testing liquids with fitting parameters, while the one modified by Joos' empirical equation works for specific liquids, such as silicone oils. The LWR equation modified by molecular self-layering model predicts well the capillary rise of carbon tetrachloride, octamethylcyclotetrasiloxane, and n-alkanes with the molecular diameter or measured solvation force data. The molecular self-layering model modified LWR equation also has good predictions on the capillary rise of silicone oils covering a wide range of bulk viscosities with the same key parameter W(0), which results from the molecular self-layering. The advantage of the molecular self-layering model over the other models reveals the importance of the layered molecularly thin wetting film ahead of the main meniscus in the energy dissipation associated with dynamic contact angle. The analysis of the capillary rise of silicone oils with a wide range of bulk viscosities provides new insights into the capillary dynamics of polymer melts.

  16. A stochastic view on column efficiency.

    Science.gov (United States)

    Gritti, Fabrice

    2018-03-09

    A stochastic model of transcolumn eddy dispersion along packed beds was derived. It was based on the calculation of the mean travel time of a single analyte molecule from one radial position to another. The exchange mechanism between two radial positions was governed by the transverse dispersion of the analyte across the column. The radial velocity distribution was obtained by flow simulations in a focused-ion-beam scanning electron microscopy (FIB-SEM) based 3D reconstruction from a 2.1 mm × 50 mm column packed with 2 μm BEH-C 18 particles. Accordingly, the packed bed was divided into three coaxial and uniform zones: (1) a 1.4 particle diameter wide, ordered, and loose packing at the column wall (velocity u w ), (2) an intermediate 130 μm wide, random, and dense packing (velocity u i ), and (3) the bulk packing in the center of the column (velocity u c ). First, the validity of this proposed stochastic model was tested by adjusting the predicted to the observed reduced van Deemter plots of a 2.1 mm × 50 mm column packed with 2 μm BEH-C 18 fully porous particles (FPPs). An excellent agreement was found for u i  = 0.93u c , a result fully consistent with the FIB-SEM observation (u i  = 0.95u c ). Next, the model was used to measure u i  = 0.94u c for 2.1 mm × 100 mm column packed with 1.6 μm Cortecs-C 18 superficially porous particles (SPPs). The relative velocity bias across columns packed with SPPs is then barely smaller than that observed in columns packed with FPPs (+6% versus + 7%). u w =1.8u i is measured for a 75 μm × 1 m capillary column packed with 2 μm BEH-C 18 particles. Despite this large wall-to-center velocity bias (+80%), the presence of the thin and ordered wall packing layer has no negative impact on the kinetic performance of capillary columns. Finally, the stochastic model of long-range eddy dispersion explains why analytical (2.1-4.6 mm i.d.) and capillary (columns can all be

  17. Capillary electrophoretic separation of inorganic and organic arsenic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Greschonig, H. [Institute of Analytical Chemistry, Karl Franzens University Graz (Austria); Schmid, M.G.; Guebitz, G. [Institute of Pharmaceutical Chemistry, Karl Franzens University Graz (Austria)

    1998-09-01

    Capillary zone electrophoresis was used to separate arsenite, arsenate, dimethylarsinic and diphenylarsinic acid, methanearsonic acid, phenyl- and p-aminophenyl arsonic acid, phenylarsineoxide and phenarsazinic acid. Anionic and uncharged species were separated in a fused silica capillary with on-column UV detection at 200 nm. A 15 mM phosphate solution adjusted to pH 6.5 containing 10 mM sodium dodecylsulfonate served as background electrolyte. The influence of pH and applied voltage on separation efficiency, as well as the feasibility of identification of arsenic compounds in spiked urine, were investigated. (orig.) With 7 figs., 1 tab., 22 refs.

  18. [Determination of acetochlor and oxyfluorfen by capillary gas chromatography].

    Science.gov (United States)

    Xiang, Wen-Sheng; Wang, Xiang-Jing; Wang, Jing; Wang, Qing

    2002-09-01

    A method is described for the determination of acetochlor and oxyfluorfen by capillary gas chromatography with FID and an SE-30 capillary column (60 m x 0.53 mm i. d., 1.5 microm), using dibutyl phthalate as the internal standard. The standard deviations for acetochlor and oxyfluorfen concentration(mass fraction) were 0.44% and 0.47% respectively. The relative standard deviations for acetochlor and oxyfluorfen were 0.79% and 0.88% and the average recoveries for acetochlor and oxyfluorfen were 99.3% and 101.1% respectively. The method is simple, rapid and accurate.

  19. Western Blotting using Capillary Electrophoresis

    OpenAIRE

    Anderson, Gwendolyn J.; Cipolla, Cynthia; Kennedy, Robert T.

    2011-01-01

    A microscale Western blotting system based on separating sodium-dodecyl sulfate protein complexes by capillary gel electrophoresis followed by deposition onto a blotting membrane for immunoassay is described. In the system, the separation capillary is grounded through a sheath capillary to a mobile X-Y translation stage which moves a blotting membrane past the capillary outlet for protein deposition. The blotting membrane is moistened with a methanol and buffer mixture to facilitate protein a...

  20. Modeling Stone Columns.

    Science.gov (United States)

    Castro, Jorge

    2017-07-11

    This paper reviews the main modeling techniques for stone columns, both ordinary stone columns and geosynthetic-encased stone columns. The paper tries to encompass the more recent advances and recommendations in the topic. Regarding the geometrical model, the main options are the "unit cell", longitudinal gravel trenches in plane strain conditions, cylindrical rings of gravel in axial symmetry conditions, equivalent homogeneous soil with improved properties and three-dimensional models, either a full three-dimensional model or just a three-dimensional row or slice of columns. Some guidelines for obtaining these simplified geometrical models are provided and the particular case of groups of columns under footings is also analyzed. For the latter case, there is a column critical length that is around twice the footing width for non-encased columns in a homogeneous soft soil. In the literature, the column critical length is sometimes given as a function of the column length, which leads to some disparities in its value. Here it is shown that the column critical length mainly depends on the footing dimensions. Some other features related with column modeling are also briefly presented, such as the influence of column installation. Finally, some guidance and recommendations are provided on parameter selection for the study of stone columns.

  1. The histories of capillary optics for x-rays and ion beams in Russia, USA, and Japan

    International Nuclear Information System (INIS)

    Umezawa, Kenji

    2009-01-01

    This article introduces the history of X-ray lens and the present situation of ion beam focusing with glass capillaries systems. The basic technology of X-ray lens using glass capillaries was independently developed over 20 years by Prof. Kumakhov in the former Soviet Union and Dr. Soejima in Japan, respectively. In the 1990's, Prof. W.M. Gibson and his coworkers intensively studied X-rays and neutron optics in Albany, NY, USA. X-ray optics with glass capillaries, in these days is well known in the world. This unique technique was fabricated to collimate X-rays. Also, new ion beam analysis technique with glass capillaries systems has been intensively developed by Dr. Nebiki and Prof. Narusawa in Kochi, Japan. These X-rays and ion beams techniques have brought new application for many fields; X-ray detector, X-ray lithography, X-ray astronomy, microdiffraction, medical therapy and biological applications. (author)

  2. ( Anogeissus leiocarpus ) timber columns

    African Journals Online (AJOL)

    A procedure for designing axially loaded Ayin (Anogeissus leiocarpus) wood column or strut has been investigated. Instead of the usual categorization of columns into short, intermediate and slender according to the value of slenderness ratio, a continuous column formula representing the three categories was derived.

  3. Column Liquid Chromatography.

    Science.gov (United States)

    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,…

  4. Analysis of anabolic steroids in body fluids by capillary gas chromatography with a two-channel detection system and a computer.

    Science.gov (United States)

    Uralets, V P; Semenova, V A; Yakushin, M A; Semenov, V A

    1983-11-25

    A method is described for analysis of multi-component mixtures of steroid metabolites in biological fluids by means of capillary gas chromatography with glass and fused-silica columns and simultaneous detection of methoxylamine-trimethylsilyl derivatives with universal flame-ionization and selective nitrogen alkali flameionization detectors. A data system was applied to the on-line treatment of the results. Computer programs were designed for precise calculation of Kováts retention indices from the known values for selected natural urinary steroids. The programs allow the selection of nitrogen-containing components, normalized chromatogram plotting for both detection channels and qualitative and quantitative analysis. Results are presented on the detection of metabolites of methandrostenolone, 17 alpha-methyltestosterone, 19-nortestosterone and fluoxymesterone.

  5. Glass sealing

    Energy Technology Data Exchange (ETDEWEB)

    Brow, R.K.; Kovacic, L.; Chambers, R.S. [Sandia National Labs., Albuquerque, NM (United States)

    1996-04-01

    Hernetic glass sealing technologies developed for weapons component applications can be utilized for the design and manufacture of fuel cells. Design and processing of of a seal are optimized through an integrated approach based on glass composition research, finite element analysis, and sealing process definition. Glass sealing procedures are selected to accommodate the limits imposed by glass composition and predicted calculations.

  6. Electrochromic Glasses.

    Science.gov (United States)

    1980-07-31

    this glass and that dipole-dipole correlations contribute to the "ferroelectric-like" character of this amorphous system. The TeO2 -W03 glasses can only...shows the dielectric constant and Fig. I(b) glass from pure TeO2 ot pure WO. In addition, glass the tan 8 of the WO glass as a function of temperature... glasses containing WO, in various glass forming nitworks of LifO-B1O0, Na:O-BzO,, and TeO2 were prepared from reagent grade oxides at 800 C - 9SO C in

  7. An improved interface for capillary zone electrophoresis-mass spectrometry

    International Nuclear Information System (INIS)

    Smith, R.D.; Loo, J.A.; Barinaga, C.J.; Udseth, H.R.

    1988-06-01

    We have recently developed an improved electrospray ionization interface for capillary electrophoresis mass-spectrometry (CZE-MS). Our initial interface employed a vacuum deposited metal film at the exit of the capillary to make an electrical contact with he eluting buffer and establish the electrospray field gradient. This interface did, however, impose significant limitations on the range of capillary electrophoretic (CE) separations that could be performed. To circumvent these limitations, an interface that does not require a metalized tip was designed nd developed. In the new approach, the electrical contact at the column exit is made through a flowing liquid sheath. The principal advantage of this interface is that it allows operation with a much broader range of electrophoresis conditions. The sheath flow can be readily varied in both composition and volume. An electrospray ionization spectrum is given for a previously intractable buffer solution. 5 refs., 2 figs

  8. Practical capillary electrophoresis

    CERN Document Server

    Weinberger, Robert

    2000-01-01

    In the 1980s, capillary electrophoresis (CE) joined high-performance liquid chromatography (HPLC) as the most powerful separation technique available to analytical chemists and biochemists. Published research using CE grew from 48 papers in the year of commercial introduction (1988) to 1200 in 1997. While only a dozen major pharmaceutical and biotech companies have reduced CE to routine practice, the applications market is showing real or potential growth in key areas, particularly in the DNA marketplace for genomic mapping and forensic identification. For drug development involving small molecules (including chiral separations), one CE instrument can replace 10 liquid chromatographs in terms of speed of analysis. CE also uses aqueous rather than organic solvents and is thus environmentally friendlier than HPLC. The second edition of Practical Capillary Electrophoresis has been extensively reorganized and rewritten to reflect modern usage in the field, with an emphasis on commercially available apparatus and ...

  9. First attempts to combine capillary tubes with photocathodes

    CERN Document Server

    Peskov, Vladimir; Sokolova, T; Radionov, I

    1999-01-01

    We describe our efforts to combine glass capillary plates, operating as a gas amplification structure at approx 1 atm, with photocathodes sensitive to visible light. Such capillary tubes are a by-product of the manufacture of Microchannel Plates and are commercially available. Preliminary tests indicate that gas gains >10 sup 3 could be achieved without photon feedback. With two capillary plates in tandem (double-step multiplication) overall gains up to 10 sup 5 were possible at counting rate <100 Hz/mm sup 2. This approach may open new possibilities for detection of visible photons by gaseous detectors. Potential advantages are: high gains, large sensitive area, high granularity, and insensitivity to magnetic fields.

  10. Automated Parallel Capillary Electrophoretic System

    Science.gov (United States)

    Li, Qingbo; Kane, Thomas E.; Liu, Changsheng; Sonnenschein, Bernard; Sharer, Michael V.; Kernan, John R.

    2000-02-22

    An automated electrophoretic system is disclosed. The system employs a capillary cartridge having a plurality of capillary tubes. The cartridge has a first array of capillary ends projecting from one side of a plate. The first array of capillary ends are spaced apart in substantially the same manner as the wells of a microtitre tray of standard size. This allows one to simultaneously perform capillary electrophoresis on samples present in each of the wells of the tray. The system includes a stacked, dual carousel arrangement to eliminate cross-contamination resulting from reuse of the same buffer tray on consecutive executions from electrophoresis. The system also has a gel delivery module containing a gel syringe/a stepper motor or a high pressure chamber with a pump to quickly and uniformly deliver gel through the capillary tubes. The system further includes a multi-wavelength beam generator to generate a laser beam which produces a beam with a wide range of wavelengths. An off-line capillary reconditioner thoroughly cleans a capillary cartridge to enable simultaneous execution of electrophoresis with another capillary cartridge. The streamlined nature of the off-line capillary reconditioner offers the advantage of increased system throughput with a minimal increase in system cost.

  11. Mass-controlled capillary viscometer for a Newtonian liquid: Viscosity of water at different temperatures

    Science.gov (United States)

    Digilov, Rafael M.; Reiner, M.

    2007-03-01

    The operation principle of the mass-controlled capillary viscometer is presented for a Newtonian liquid. The derived equation for the temporal changes of the mass in a liquid column draining under gravity through a discharge capillary tube accounts self-consistently for the inertial convective term associated with the acceleration effect. The viscosity of water measured at different temperatures using the new approach is in good agreement with literature data.

  12. Inert carriers for column extraction chromatography

    International Nuclear Information System (INIS)

    Katykhin, G.S.

    1978-01-01

    Inert carriers used in column extraction chromatography are reviewed. Such carriers are devided into two large groups: hydrophilic carriers which possess high surface energy and are well wetted only with strongly polar liquids (kieselguhrs, silica gels, glasses, cellulose, Al 2 O 3 ) and water-repellent carriers which possess low surface energy and are well wetted with various organic solvents (polyethylene, polytetrafluorethylene polytrifluorochlorethylene). Properties of various carriers are presented: structure, chemical and radiation stability, adsorption properties, extracting agent capacity. The effect of structure and sizes of particles on the efficiency of chromatography columns is considered. Ways of immovable phase deposition on the carrier and the latter's regeneration. Peculiarities of column packing for preparative and continuous chromatography are discussed

  13. Capillary Condensation in Confined Media

    OpenAIRE

    Charlaix, Elisabeth; Ciccotti, Matteo

    2009-01-01

    28 pages - To appear in 2010 in the Handbook of Nanophysics - Vol 1 - Edited by Klaus Sattler - CRC Press; We review here the physics of capillary condensation of liquids in confined media, with a special regard to the application in nanotechnologies. The thermodynamics of capillary condensation and thin film adsorption are first exposed along with all the relevant notions. The focus is then shifted to the modelling of capillary forces, to their measurements techniques (including SFA, AFM and...

  14. Capillary waves in slow motion

    International Nuclear Information System (INIS)

    Seydel, Tilo; Tolan, Metin; Press, Werner; Madsen, Anders; Gruebel, Gerhard

    2001-01-01

    Capillary wave dynamics on glycerol surfaces has been investigated by means of x-ray photon correlation spectroscopy performed at grazing angles. The measurements show that thermally activated capillary wave motion is slowed down exponentially when the sample is cooled below 273 K. This finding directly reflects the freezing of the surface waves. The wave-number dependence of the measured time constants is in quantitative agreement with theoretical predictions for overdamped capillary waves

  15. Small Column Ion Exchange

    International Nuclear Information System (INIS)

    Huff, Thomas

    2010-01-01

    Small Column Ion Exchange (SCIX) leverages a suite of technologies developed by DOE across the complex to achieve lifecycle savings. Technologies are applicable to multiple sites. Early testing supported multiple sites. Balance of SRS SCIX testing supports SRS deployment. A forma Systems Engineering Evaluation (SEE) was performed and selected Small Column Ion Exchange columns containing Crystalline Silicotitanate (CST) in a 2-column lead/lag configuration. SEE considered use of Spherical Resorcinol-Formaldehyde (sRF). Advantages of approach at SRS include: (1) no new buildings, (2) low volume of Cs waste in solid form compared to aqueous strip effluent; and availability of downstream processing facilities for immediate processing of spent resin.

  16. Capillary waves of compressible fluids

    International Nuclear Information System (INIS)

    Falk, Kerstin; Mecke, Klaus

    2011-01-01

    The interplay of thermal noise and molecular forces is responsible for surprising features of liquids on sub-micrometer lengths-in particular at interfaces. Not only does the surface tension depend on the size of an applied distortion and nanoscopic thin liquid films dewet faster than would be expected from hydrodynamics, but also the dispersion relation of capillary waves differ at the nanoscale from the familiar macroscopic behavior. Starting with the stochastic Navier-Stokes equation we study the coupling of capillary waves to acoustic surface waves which is possible in compressible fluids. We find propagating 'acoustic-capillary waves' at nanometer wavelengths where in incompressible fluids capillary waves are overdamped.

  17. Glass consistency and glass performance

    International Nuclear Information System (INIS)

    Plodinec, M.J.; Ramsey, W.G.

    1994-01-01

    Glass produced by the Defense Waste Processing Facility (DWPF) will have to consistently be more durable than a benchmark glass (evaluated using a short-term leach test), with high confidence. The DWPF has developed a Glass Product Control Program to comply with this specification. However, it is not clear what relevance product consistency has on long-term glass performance. In this report, the authors show that DWPF glass, produced in compliance with this specification, can be expected to effectively limit the release of soluble radionuclides to natural environments. However, the release of insoluble radionuclides to the environment will be limited by their solubility, and not glass durability

  18. Colloidal glasses

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Colloidal glasses. Glassy state is attained when system fails to reach equilibrium due to crowding of constituent particles. In molecular glasses, glassy state is reached by rapidly lowering the temperature. In colloidal glasses, glassy state is reached by increasing the ...

  19. JCE Feature Columns

    Science.gov (United States)

    Holmes, Jon L.

    1999-05-01

    The Features area of JCE Online is now readily accessible through a single click from our home page. In the Features area each column is linked to its own home page. These column home pages also have links to them from the online Journal Table of Contents pages or from any article published as part of that feature column. Using these links you can easily find abstracts of additional articles that are related by topic. Of course, JCE Online+ subscribers are then just one click away from the entire article. Finding related articles is easy because each feature column "site" contains links to the online abstracts of all the articles that have appeared in the column. In addition, you can find the mission statement for the column and the email link to the column editor that I mentioned above. At the discretion of its editor, a feature column site may contain additional resources. As an example, the Chemical Information Instructor column edited by Arleen Somerville will have a periodically updated bibliography of resources for teaching and using chemical information. Due to the increase in the number of these resources available on the WWW, it only makes sense to publish this information online so that you can get to these resources with a simple click of the mouse. We expect that there will soon be additional information and resources at several other feature column sites. Following in the footsteps of the Chemical Information Instructor, up-to-date bibliographies and links to related online resources can be made available. We hope to extend the online component of our feature columns with moderated online discussion forums. If you have a suggestion for an online resource you would like to see included, let the feature editor or JCE Online (jceonline@chem.wisc.edu) know about it. JCE Internet Features JCE Internet also has several feature columns: Chemical Education Resource Shelf, Conceptual Questions and Challenge Problems, Equipment Buyers Guide, Hal's Picks, Mathcad

  20. On Capillary Rise and Nucleation

    Science.gov (United States)

    Prasad, R.

    2008-01-01

    A comparison of capillary rise and nucleation is presented. It is shown that both phenomena result from a balance between two competing energy factors: a volume energy and a surface energy. Such a comparison may help to introduce nucleation with a topic familiar to the students, capillary rise. (Contains 1 table and 3 figures.)

  1. Capillary optics for radiation focusing

    International Nuclear Information System (INIS)

    Peurrung, A.J.; Reeder, P.L.; Bliss, M.; Craig, R.A.; Lepel, E.A.; Stromswold, D.C.; Stoffels, J.; Sunberg, D.S.; Tenny, H.

    1996-11-01

    Capillary lens technology may ultimately bring benefits to neutron and x-ray-based science like conventional lenses with visible light. Although the technology is not yet 10 years old, these lenses have already had a significant impact in engineering, science, and medicine. Capillary lenses are advantageous when it is desirable to increase the radiation flux at a location without regard to its angular divergence. PNNL has worked to improve the technology in several ways. A single, optimally tapered capillary was manufactured, which allows intensity gains of a factor of 270 for an initially parallel, incident x-ray beam. Feasibility of constructing neutron lenses using 58 Ni (particularly effective at reflecting neutrons) has been explored. Three applications for capillary optics have been identified and studied: neutron telescope, Gandolphi x-ray diffractometry, and neutron radiotherapy. A brief guide is given for determining which potential applications are likely to be helped by capillary optics

  2. On hydraulics of capillary tubes

    Directory of Open Access Journals (Sweden)

    N.G. Aloyan

    2016-03-01

    Full Text Available The article considers the laws of motion of water in the capillary tubes, taken as a model for flowing well, on the analogical net count device. For capillary tube the lower limit value of flow rate is empirically determined above which the total hydraulic resistance of the capillary is practically constant. The specificity of the phenomenon is that the regime of motion, by a Reynolds number, for a given flow rate still remains laminar. This circumstance can perplex the specialists, so the author invites them to the scientific debate on the subject of study. Obviously, to identify the resulting puzzle it is necessary to conduct a series of experiments using capillaries of different lengths and diameters and with different values of overpressure. The article states that in tubes with very small diameter the preliminary magnitude of capillary rise of water in the presence of flow plays no role and can be neglected.

  3. Biomedical applications of capillary electrophoresis

    International Nuclear Information System (INIS)

    Kartsova, L A; Bessonova, E A

    2015-01-01

    The review deals with modern analytical approaches used in capillary electrophoresis for solving medical and biological problems: search for biomarkers of various diseases and rapid diagnosis based on characteristic profiles of biologically active compounds by capillary electrophoresis with mass spectrometric detection; monitoring of the residual drugs in biological fluids for evaluating the efficiency of drug therapy; testing of the enantiomeric purity of pharmaceutical products; the use of novel materials as components of stationary and pseudo-stationary phases in capillary electrophoresis and capillary electrochromatography to increase the selectivity of separation of components of complex matrices; and identification of various on-line preconcentration techniques to reduce the detection limits of biologically active analytes. A topical trend in capillary electrophoresis required in clinical practice, viz., the design of microfluidic systems, is discussed. The bibliography includes 173 references

  4. Silicate glasses

    International Nuclear Information System (INIS)

    Lutze, W.

    1988-01-01

    Vitrification of liquid high-level radioactive wastes has received the greatest attention, world-wide, compared to any other HLW solidification process. The waste form is a borosilicate-based glass. The production of phosphate-based glass has been abandoned in the western world. Only in the Soviet Union are phosphate-based glasses still being developed. Vitrification techniques, equipment and processes and their remote operation have been developed and studied for almost thirty years and have reached a high degree of technical maturity. Industrial demonstration of the vitrification process has been in progress since 1978. This chapter is a survey of world-wide research and development efforts in nuclear waste glasses and its production technology. The principal glasses considered are silicate glasses which contain boron, i.e., borosilicate glasses

  5. Micro-column plasma emission liquid chromatograph. [Patent application

    Science.gov (United States)

    Gay, D.D.

    1982-08-12

    In a direct current plasma emission spectrometer for use in combination with a microcolumn liquid chromatograph, an improved plasma source unit is claimed. The plasma source unit includes a quartz capillary tube having an inlet means, outlet off gas means and a pair of spaced electrodes defining a plasma region in the tube. The inlet means is connected to and adapted to receive eluant of the liquid chromatograph along with a stream of plasma-forming gas. There is an opening through the wall of the capillary tube penetrating into the plasma region. A soft glass capillary light pipe is disposed at the opening, is connected to the spectrometer, and is adapted to transmit light passing from the plasma region to the spectrometer. There is also a source of electromotive force connected to the electrodes sufficient to initiate and sustain a plasma in the plasma region of the tube.

  6. Experimental and Numerical Study of FRP Encased Composite Concrete Columns

    Directory of Open Access Journals (Sweden)

    Mohsen Ishaghian

    2017-02-01

    Full Text Available A new type of composite column is presented and assessed through experimental testing and numerical modeling. The objective of this research is to investigate design options for a composite column without the use of ferrous materials. This is to avoid the current problem of deterioration of concrete due to expansion of rusting reinforcement members. Such a target can be achieved by replacing the steel reinforcement of concrete columns with pultruded I-shape glass FRP structural sections. The composite column utilizes a glass FRP tube that surrounds a pultruded I-section glass FRP, which is subsequently filled with concrete. The GFRP tube acts as a stay-in-place form in addition to providing confinement to the concrete. A total of four composite columns were tested under monotonic axial loading. The experimental ultimate capacity of each of the tested composite column was compared to the predicted numerical capacity using ANSYS program. The comparison showed that the predicted numerical values were in good agreement with the experimental ones.

  7. Physiological factors influencing capillary growth.

    Science.gov (United States)

    Egginton, S

    2011-07-01

    (1) Angiogenesis (growth of new capillaries from an existing capillary bed) may result from a mismatch in microvascular supply and metabolic demand (metabolic error signal). Krogh examined the distribution and number of capillaries to explore the correlation between O(2) delivery and O(2) consumption. Subsequently, the heterogeneity in angiogenic response within a muscle has been shown to reflect either differences in fibre type composition or mechanical load. However, local control leads to targetted angiogenesis in the vicinity of glycolytic fibre types following muscle stimulation, or oxidative fibres following endurance training, while heterogeneity of capillary spacing is maintained during ontogenetic growth. (2) Despite limited microscopy resolution and lack of specific markers, Krogh's interest in the structure of the capillary wall paved the way for understanding the mechanisms of capillary growth. Angiogenesis may be influenced by the response of perivascular or stromal cells (fibroblasts, macrophages and pericytes) to altered activity, likely acting as a source for chemical signals modulating capillary growth such as vascular endothelial growth factor. In addition, haemodynamic factors such as shear stress and muscle stretch play a significant role in adaptive remodelling of the microcirculation. (3) Most indices of capillarity are highly dependent on fibre size, resulting in possible bias because of scaling. To examine the consequences of capillary distribution, it is therefore helpful to quantify the area of tissue supplied by individual capillaries. This allows the spatial limitations inherent in most models of tissue oxygenation to be overcome generating an alternative approach to Krogh's tissue cylinder, the capillary domain, to improve descriptions of intracellular oxygen diffusion. © 2010 The Author. Acta Physiologica © 2010 Scandinavian Physiological Society.

  8. Distillation Column Flooding Predictor

    Energy Technology Data Exchange (ETDEWEB)

    George E. Dzyacky

    2010-11-23

    The Flooding Predictor™ is a patented advanced control technology proven in research at the Separations Research Program, University of Texas at Austin, to increase distillation column throughput by over 6%, while also increasing energy efficiency by 10%. The research was conducted under a U. S. Department of Energy Cooperative Agreement awarded to George Dzyacky of 2ndpoint, LLC. The Flooding Predictor™ works by detecting the incipient flood point and controlling the column closer to its actual hydraulic limit than historical practices have allowed. Further, the technology uses existing column instrumentation, meaning no additional refining infrastructure is required. Refiners often push distillation columns to maximize throughput, improve separation, or simply to achieve day-to-day optimization. Attempting to achieve such operating objectives is a tricky undertaking that can result in flooding. Operators and advanced control strategies alike rely on the conventional use of delta-pressure instrumentation to approximate the column’s approach to flood. But column delta-pressure is more an inference of the column’s approach to flood than it is an actual measurement of it. As a consequence, delta pressure limits are established conservatively in order to operate in a regime where the column is never expected to flood. As a result, there is much “left on the table” when operating in such a regime, i.e. the capacity difference between controlling the column to an upper delta-pressure limit and controlling it to the actual hydraulic limit. The Flooding Predictor™, an innovative pattern recognition technology, controls columns at their actual hydraulic limit, which research shows leads to a throughput increase of over 6%. Controlling closer to the hydraulic limit also permits operation in a sweet spot of increased energy-efficiency. In this region of increased column loading, the Flooding Predictor is able to exploit the benefits of higher liquid

  9. Nuclear reactor control column

    International Nuclear Information System (INIS)

    Bachovchin, D.M.

    1982-01-01

    The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest crosssectional area, the intermediate section of the control column has the smallest cross-sectional area, and the lowermost section of the control column has the intermediate cross-sectional area. In this manner, the area of the uppermost section can be established such that when the reactor coolant is flowing under normal conditions therethrough, the absorber balls will be lifted and suspended in a fluidized bed manner in the upper section. However, when the reactor coolant flow falls below a predetermined value, the absorber balls will fall through the intermediate section and into the lowermost section, thereby reducing the reactivity of the reactor core and shutting down the reactor

  10. Improvements in solvent extraction columns

    International Nuclear Information System (INIS)

    Aughwane, K.R.

    1987-01-01

    Solvent extraction columns are used in the reprocessing of irradiated nuclear fuel. For an effective reprocessing operation a solvent extraction column is required which is capable of distributing the feed over most of the column. The patent describes improvements in solvent extractions columns which allows the feed to be distributed over an increased length of column than was previously possible. (U.K.)

  11. Capillaries for use in a multiplexed capillary electrophoresis system

    Science.gov (United States)

    Yeung, E.S.; Chang, H.T.; Fung, E.N.

    1997-12-09

    The invention provides a side-entry optical excitation geometry for use in a multiplexed capillary electrophoresis system. A charge-injection device is optically coupled to capillaries in the array such that the interior of a capillary is imaged onto only one pixel. In Sanger-type 4-label DNA sequencing reactions, nucleotide identification (``base calling``) is improved by using two long-pass filters to split fluorescence emission into two emission channels. A binary poly(ethyleneoxide) matrix is used in the electrophoretic separations. 19 figs.

  12. Analysis of Capillary Coating Die Flow in an Optical Fiber Coating Applicator

    OpenAIRE

    Kyoungjin Kim

    2011-01-01

    Viscous heating becomes significant in the high speed resin coating process of glass fibers for optical fiber manufacturing. This study focuses on the coating resin flows inside the capillary coating die of optical fiber coating applicator and they are numerically simulated to examine the effects of viscous heating and subsequent temperature increase in coating resin. Resin flows are driven by fast moving glass fiber and the pressurization at the coating die inlet, while ...

  13. Buckling of liquid columns

    NARCIS (Netherlands)

    Habibi, M.; Rahmani, Y.; Bonn, D.; Ribe, N.M.

    2010-01-01

    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 modes—viscous, gravitational, and

  14. Solvent extraction columns

    International Nuclear Information System (INIS)

    Middleton, P.; Smith, J.R.

    1979-01-01

    In pulsed columns for use in solvent extraction processes, e.g. the reprocessing of nuclear fuel, the horizontal perforated plates inside the column are separated by interplate spacers manufactured from metallic neutron absorbing material. The spacer may be in the form of a spiral or concentric circles separated by radial limbs, or may be of egg-box construction. Suitable neutron absorbing materials include stainless steel containing boron or gadolinium, hafnium metal or alloys of hafnium. (UK)

  15. Capillary Flow of Liquid Metals in Brazing

    Science.gov (United States)

    Dehsara, Mohammad

    Capillary flow is driven or controlled by capillary forces, exerted at the triple line where the fluid phases meet the solid boundary. Phase field (PF) models naturally accommodate diffusive triple line motion with variable contact angle, thus allowing for the no-slip boundary condition without the stress singularities. Moreover, they are uniquely suited for modeling of topological discontinuities which often arise during capillary flows. In this study, we consider diffusive triple line motion within two PF models: the compositionally compressible (CC) and the incompressible (IC) models. We derive the IC model as a systematic approximation to the CC model, based on a suitable choice of continuum velocity field. The CC model, applied to the fluids of dissimilar mass densities, exhibits a computational instability at the triple line. The IC model perfectly represents the analytic equilibria. We develop the parameter identification procedure and show that the triple line kinetics can be well represented by the IC model's diffusive boundary condition. The IC model is first tested by benchmarking the phase-field and experimental kinetics of water, and silicone oil spreading over the glass plates in which two systems do not interact with the substrate. Then, two high-temperature physical settings involving spreading of the molten Al-Si alloy: one over a rough wetting substrate, the other over a non-wetting substrate are modeled in a T-joint structure which is a typical geometric configuration for many brazing and soldering applications. Surface roughness directly influences the spreading of the molten metal by causing break-ups of the liquid film and trapping the liquid away from the joint. In the early stages of capillary flow over non-wetting surface, the melting and flow are concurrent, so that the kinetics of wetting is strongly affected by the variations in effective viscosity of the partially molten metal. We define adequate time-dependent functions for the

  16. Automation and integration of multiplexed on-line sample preparation with capillary electrophoresis for DNA sequencing

    Energy Technology Data Exchange (ETDEWEB)

    Tan, H.

    1999-03-31

    The purpose of this research is to develop a multiplexed sample processing system in conjunction with multiplexed capillary electrophoresis for high-throughput DNA sequencing. The concept from DNA template to called bases was first demonstrated with a manually operated single capillary system. Later, an automated microfluidic system with 8 channels based on the same principle was successfully constructed. The instrument automatically processes 8 templates through reaction, purification, denaturation, pre-concentration, injection, separation and detection in a parallel fashion. A multiplexed freeze/thaw switching principle and a distribution network were implemented to manage flow direction and sample transportation. Dye-labeled terminator cycle-sequencing reactions are performed in an 8-capillary array in a hot air thermal cycler. Subsequently, the sequencing ladders are directly loaded into a corresponding size-exclusion chromatographic column operated at {approximately} 60 C for purification. On-line denaturation and stacking injection for capillary electrophoresis is simultaneously accomplished at a cross assembly set at {approximately} 70 C. Not only the separation capillary array but also the reaction capillary array and purification columns can be regenerated after every run. DNA sequencing data from this system allow base calling up to 460 bases with accuracy of 98%.

  17. Recycle Glass in Foam Glass Production

    DEFF Research Database (Denmark)

    Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

    The foam glass industry turn recycle glass into heat insulating building materials. The foaming process is relative insensitive to impurities in the recycle glass. It is therefore considered to play an important role in future glass recycling. We show and discuss trends of use of recycled glasses...... in foam glass industry and the supply sources and capacity of recycle glass....

  18. Monitoring the behaviour of 4-ketocyclophosphamide versus cyclophosphamide during capillary gas chromatography by mass spectrometry

    NARCIS (Netherlands)

    Bruijn, de E.A.; Oosterom, van A.T.; Leclercq, P.A.; Haan, de J.W.; Ven, van de L.J.M.; Tjaden, U.R.

    1987-01-01

    Capillary Gas Chromatography (CGC) is capable of determining underivatized cyclophosphamide (CPA) using SCOT OV 275 columns. Then CPA is subjected to in situ degradation resulting in formation of a cyclization product which can be determined selectively in biological fluids. In routine bioanalysis

  19. Topographical properties of polymer films deposited in capillaries for electrophoretic separations of large organic molecules

    Czech Academy of Sciences Publication Activity Database

    Guryča, Vilém; Pacáková, V.; Tlusťáková, Marie; Štulík, K.; Michálek, Jiří

    2004-01-01

    Roč. 27, č. 13 (2004), s. 1121-1129 ISSN 1615-9306 R&D Projects: GA AV ČR IBS4050005; GA AV ČR KSK4055109 Institutional research plan: CEZ:AV0Z4050913 Keywords : capillary electrophoresis * hydrogel polymer coating * column technology Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.927, year: 2004

  20. Direct measurement of lithium in whole blood using microchip capillary electrophoresis with integrated conductivity detection

    NARCIS (Netherlands)

    Vrouwe, E.X.; Lüttge, Regina; van den Berg, Albert

    2004-01-01

    The direct measurement of lithium in whole blood is described. Using microchip capillary electrophoresis (CE) with defined sample loading and applying the principles of column coupling, alkali metals were determined in a drop of whole blood. Blood collected from a finger stick was mixed with

  1. A fully automated fast analysis system for capillary gas chromatography. Part 1. Automation of system control

    NARCIS (Netherlands)

    Snijders, H.M.J.; Rijks, J.P.E.M.; Bombeeck, A.J.; Rijks, J.A.; Sandra, P.; Lee, M.L.

    1992-01-01

    This paper is dealing with the design, the automation and evaluation of a high speed capillary gas chromatographic system. A combination of software and hardware was developed for a new cold trap/reinjection device that allows selective solvent eliminating and on column sample enrichment and an

  2. DNA typing by capillary electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, N.

    1997-10-08

    Capillary electrophoresis is becoming more and more important in nucleic acid analysis including DNA sequencing, typing and disease gene measurements. This work summarized the background of DNA typing. The recent development of capillary electrophoresis was also discussed. The second part of the thesis showed the principle of DNA typing based on using the allelic ladder as the absolute standard ladder in capillary electrophoresis system. Future work will be focused on demonstrating DNA typing on multiplex loci and examples of disease diagnosis in the on-line format of PCR-CE. Also capillary array electrophoresis system should allow high throughput, fast speed DNA typing. Only the introduction and conclusions for this report are available here. A reprint was removed for separate processing.

  3. Microchip capillary electrophoresis for point-of-care analysis of lithium

    NARCIS (Netherlands)

    Vrouwe, E.X.; Luttge, R.; Vermes, I.; Berg, van den A.

    2007-01-01

    Background: Microchip capillary electrophoresis (CE) is a promising method for chemical analysis of complex samples such as whole blood. We evaluated the method for point-of-care testing of lithium. Methods: Chemical separation was performed on standard glass microchip CE devices with a conductivity

  4. A Chip-Capillary Hybrid Device for Automated Transfer of Sample Pre-Separated by Capillary Isoelectric Focusing to Parallel Capillary Gel Electrophoresis for Two-Dimensional Protein Separation

    Science.gov (United States)

    Lu, Joann J.; Wang, Shili; Li, Guanbin; Wang, Wei; Pu, Qiaosheng; Liu, Shaorong

    2012-01-01

    In this report, we introduce a chip-capillary hybrid device to integrate capillary isoelectric focusing (CIEF) with parallel capillary sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS-PAGE) or capillary gel electrophoresis (CGE) toward automating two-dimensional (2D) protein separations. The hybrid device consists of three chips that are butted together. The middle chip can be moved between two positions to re-route the fluidic paths, which enables the performance of CIEF and injection of proteins partially resolved by CIEF to CGE capillaries for parallel CGE separations in a continuous and automated fashion. Capillaries are attached to the other two chips to facilitate CIEF and CGE separations and to extend the effective lengths of CGE columns. Specifically, we illustrate the working principle of the hybrid device, develop protocols for producing and preparing the hybrid device, and demonstrate the feasibility of using this hybrid device for automated injection of CIEF-separated sample to parallel CGE for 2D protein separations. Potentials and problems associated with the hybrid device are also discussed. PMID:22830584

  5. Capillary viscosimetry on ferrofluids

    International Nuclear Information System (INIS)

    Pop, L M; Odenbach, S

    2008-01-01

    Experiments performed for different ferrofluids under shear flow have shown that an increase of the magnetic field strength applied to the sample yields an increase of the fluid's viscosity, the so called magnetoviscous effect. It has been shown that the magnitude of the effect is strongly related to the modification of the microstructure of ferrofluids and can be influenced by varying both the dipole-dipole interaction between the particles and the concentration of large particles within the fluid. This result has been further used to synthesize new ferrofluids which, on one hand, are more compatible for technical applications but, on the other hand, led to difficulties for the experimenters in measuring the viscous behavior in the presence of a magnetic field. To overcome this problem, a specially designed ferrofluid-compatible capillary viscometer has been developed. Within this paper, the experimental setup as well as experimental results concerning the investigation of the magnetoviscous effect in both diluted and concentrated cobalt-based ferrofluids are presented

  6. Cosmos & Glass

    DEFF Research Database (Denmark)

    Beim, Anne

    1996-01-01

    The article unfolds the architectural visions of glass by Bruno Taut. It refers to inspirations by Paul Sheerbart and litterature and the Crystal Chain, also it analyses the tectonic univers that can be found in the glass pavillion for the Werkbund exposition in Cologne....

  7. Glass Glimpsed

    DEFF Research Database (Denmark)

    Lock, Charles

    2015-01-01

    Glass in poetry as it reflects the viewer and as its power of reflection are both reduced and enhanced by technology.......Glass in poetry as it reflects the viewer and as its power of reflection are both reduced and enhanced by technology....

  8. Spin glasses

    CERN Document Server

    Bovier, Anton

    2007-01-01

    Spin glass theory is going through a stunning period of progress while finding exciting new applications in areas beyond theoretical physics, in particular in combinatorics and computer science. This collection of state-of-the-art review papers written by leading experts in the field covers the topic from a wide variety of angles. The topics covered are mean field spin glasses, including a pedagogical account of Talagrand's proof of the Parisi solution, short range spin glasses, emphasizing the open problem of the relevance of the mean-field theory for lattice models, and the dynamics of spin glasses, in particular the problem of ageing in mean field models. The book will serve as a concise introduction to the state of the art of spin glass theory, usefull to both graduate students and young researchers, as well as to anyone curious to know what is going on in this exciting area of mathematical physics.

  9. Evaluation of Carbon Nanotubes Functionalized Polydimethylsiloxane Based Coatings for In-Tube Solid Phase Microextraction Coupled to Capillary Liquid Chromatography

    OpenAIRE

    Neus Jornet-Martínez; Pascual Serra-Mora; Yolanda Moliner-Martínez; Rosa Herráez-Hernández; Pilar Campíns-Falcó

    2015-01-01

    In the present work, the performance of carbon nanotubes (c-CNTs) functionalized polydimethylsiloxane (PDMS) based coatings as extractive phases for in-tube solid phase microextraction (IT-SPME) coupled to Capillary LC (CapLC) has been evaluated. Carboxylic-single walled carbon nanotubes (c-SWNTs) and carboxylic-multi walled carbon nanotubes (c-MWNTs) have been immobilized on the activated surface of PDMS capillary columns. The effect of different percentages of diphenyl groups in the PDMS ex...

  10. Hydrodynamic Study Of Column Bioleaching Processes

    Directory of Open Access Journals (Sweden)

    Sadowski Zygmunt

    2015-06-01

    Full Text Available The modelling of flow leaching solution through the porous media has been considered. The heap bioleaching process can be tested using the column experimental equipment. This equipment was employed to the hydrodynamic studies of copper ore bioleaching. The copper ore (black shale ore with the support, inertial materials (glass small balls and polyethylene beads was used to the bioleaching tests. The packed beds were various composition, the ore/support ratio was changed. The correlation between the bed porosity and bioleaching kinetics, and copper recovery was investigated.

  11. A Partial Equilibrium Theory for Drops and Capillary Liquids

    International Nuclear Information System (INIS)

    Searcy, Alan W.; Beruto, Dario T.; Barberis, Fabrizio

    2006-01-01

    The two-century old theory of Young and Laplace retains a powerful influence on surface and interface studies because it quantitatively predicts the height of rise of capillary liquids from the contact angles of drops. But the classical theory does not acknowledge that equilibrium requires separate minimization of partial free energies of one-component liquids bonded to immiscible solids. We generalize a theorem of Gibbs and Curie to obtain a partial equilibrium (PE) theory that does so and that also predicts the height of capillary rise from contact angles of drops. Published observations and our own measurements of contact angles of water bonded to glass and Teflon surfaces support the conclusion of PE theory that contact angles of meniscuses and of drops are different dependent variables. PE theory provides thermodynamic and kinetic guidance to nanoscale processes that the classical theory obscures, as illustrated by examples in our concluding section

  12. Fiber pigtailed thin wall capillary coupler for excitation of microsphere WGM resonator.

    Science.gov (United States)

    Wang, Hanzheng; Lan, Xinwei; Huang, Jie; Yuan, Lei; Kim, Cheol-Woon; Xiao, Hai

    2013-07-01

    In this paper, we demonstrate a fiber pigtailed thin wall capillary coupler for excitation of Whispering Gallery Modes (WGMs) of microsphere resonators. The coupler is made by fusion-splicing an optical fiber with a capillary tube and consequently etching the capillary wall to a thickness of a few microns. Light is coupled through the peripheral contact between inserted microsphere and the etched capillary wall. The coupling efficiency as a function of the wall thickness was studied experimentally. WGM resonance with a Q-factor of 1.14 × 10(4) was observed using a borosilicate glass microsphere with a diameter of 71 μm. The coupler operates in the reflection mode and provides a robust mechanical support to the microsphere resonator. It is expected that the new coupler may find broad applications in sensors, optical filters and lasers.

  13. PERFORMANCE OF A PACKED LIQUID-LIQUID EXTRACTION COLUMN

    Directory of Open Access Journals (Sweden)

    İ. Metin HASDEMİR

    1999-03-01

    Full Text Available The influence of feed ratios ((LE/LR on the performance of a packed liquid-liquid extraction column, with a diameter of 5.86 cm and a column height of 132 cm was investigated. The column is made of borosilicate glass and packed with 10 x 10 mm glass Raschig rings. In this study, a ternary system composed of water + propionic acid + trichloroethylene was used. The data used to triangular diagram were obtained experimentally. The overall mass transfer coefficients, the numbers of overall mass transfer units, the heights of mass transfer units, the numbers of theoretical stages and height equivalent to a theoretical stage (H. E. T. S. values were calculated and compared with each other.

  14. Confocal laser-induced fluorescence detector for narrow capillary system with yoctomole limit of detection.

    Science.gov (United States)

    Weaver, Mitchell T; Lynch, Kyle B; Zhu, Zaifang; Chen, Huang; Lu, Joann J; Pu, Qiaosheng; Liu, Shaorong

    2017-04-01

    Laser-induced fluorescence (LIF) detectors for low-micrometer and sub-micrometer capillary on-column detection are not commercially available. In this paper, we describe in details how to construct a confocal LIF detector to address this issue. We characterize the detector by determining its limit of detection (LOD), linear dynamic range (LDR) and background signal drift; a very low LOD (~70 fluorescein molecules or 12 yoctomole fluorescein), a wide LDR (greater than 3 orders of magnitude) and a small background signal drift (~1.2-fold of the root mean square noise) are obtained. For detecting analytes inside a low-micrometer and sub-micrometer capillary, proper alignment is essential. We present a simple protocol to align the capillary with the optical system and use the position-lock capability of a translation stage to fix the capillary in position during the experiment. To demonstrate the feasibility of using this detector for narrow capillary systems, we build a 2-μm-i.d. capillary flow injection analysis (FIA) system using the newly developed LIF prototype as a detector and obtain an FIA LOD of 14 zeptomole fluorescein. We also separate a DNA ladder sample by bare narrow capillary - hydrodynamic chromatography and use the LIF prototype to monitor the resolved DNA fragments. We obtain not only well-resolved peaks but also the quantitative information of all DNA fragments. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Rugged Large Volume Injection for Sensitive Capillary LC-MS Environmental Monitoring

    Directory of Open Access Journals (Sweden)

    Hanne Roberg-Larsen

    2017-08-01

    Full Text Available A rugged and high throughput capillary column (cLC LC-MS switching platform using large volume injection and on-line automatic filtration and filter back-flush (AFFL solid phase extraction (SPE for analysis of environmental water samples with minimal sample preparation is presented. Although narrow columns and on-line sample preparation are used in the platform, high ruggedness is achieved e.g., injection of 100 non-filtrated water samples did not result in a pressure rise/clogging of the SPE/capillary columns (inner diameter 300 μm. In addition, satisfactory retention time stability and chromatographic resolution were also features of the system. The potential of the platform for environmental water samples was demonstrated with various pharmaceutical products, which had detection limits (LOD in the 0.05–12.5 ng/L range. Between-day and within-day repeatability of selected analytes were <20% RSD.

  16. A capillary-pumped loop (CPL) with microcone-shaped capillary structure for cooling electronic devices

    International Nuclear Information System (INIS)

    Jung, Jung-Yeul; Oh, Hoo-Suk; Kwak, Ho-Young; Lee, Dae Keun; Choi, Kyong Bin; Dong, Sang Keun

    2008-01-01

    A MEMS-based integrated capillary-pumped loop (CPL), which can be used for cooling electronic devices such as the CPU of a personal computer or notebook, was developed. The CPL consists of an evaporator and condenser both with the same size of 30 mm × 30 mm × 5.15 mm, which were fabricated using two layers of glass wafer and one layer of silicon wafer. A key element of the CPL is that the 480 ± 15 µm thickness silicon wafer where an array of 56 × 56 cone-shaped microholes that generates the capillary forces was fabricated and inserted above the compensation cavity for liquid transportation instead of a porous wick in the evaporator. The same cone-shaped microstructure was used in the condenser to create a stable interface between the liquid and vapor phases. The CPL fabricated was tested under various conditions such as different relative heights, fill ratios and heat fluxes. The operation conditions of the CPL were varied according to the relative height and fill ratios. With an allowable temperature of 110 °C on the evaporator surfaces, the CPL can handle a heat flux of about 6.22 W cm −2 for the air-cooled condenser. Steady-state operation conditions were achieved within 10 min. (note)

  17. Slow Physics: Recording the Ascent and Descent of a Water Column

    Science.gov (United States)

    Lindén, Johan; Källman, Kjell-Mikael; Holm, Erik

    2018-01-01

    A glass filled with carbon dioxide gas upside down on a plate of water constitutes an excellent demonstration of the solubility of gases. If the water level on the plate is maintained the CO[subscript 2] will slowly dissolve and the column of water will rise inside the glass, without quite reaching the ceiling, before an opposite process sets in:…

  18. Periodic imidazolium-bridged hybrid monolith for high-efficiency capillary liquid chromatography with enhanced selectivity.

    Science.gov (United States)

    Qiao, Xiaoqiang; Zhang, Niu; Han, Manman; Li, Xueyun; Qin, Xinying; Shen, Shigang

    2017-03-01

    A novel periodic imidazolium-bridged hybrid monolithic column was developed. With diene imidazolium ionic liquid 1-allyl-3-vinylimidazolium bromide as both cross-linker and organic functionalized reagent, a new periodic imidazolium-bridged hybrid monolithic column was facilely prepared in capillary with homogeneously distributed cationic imidazolium by a one-step free-radical polymerization with polyhedral oligomeric silsesquioxane methacryl substituted. The successful preparation of the new column was verified by Fourier transform infrared spectroscopy, scanning electron microscopy, elemental analysis, and surface area analysis. Most interestingly, the bonded amount of 1-allyl-3-vinylimidazolium bromide of the new column is three times higher than that of the conventional imidazolium-embedded hybrid monolithic column and the specific surface area of the column reached 478 m 2 /g. The new column exhibited high stability, excellent separation efficiency, and enhanced separation selectivity. The column efficiency reached 151 000 plates/m for alkylbenzenes. Furthermore, the new column was successfully used for separation of highly polar nucleosides and nucleic acid bases with pure water as mobile phase and even bovine serum albumin tryptic digest. All these results demonstrate the periodic imidazolium-bridged hybrid monolithic column is a good separation media and can be used for chromatographic separation of small molecules and complex biological samples with high efficiency. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Columns in Clay

    Science.gov (United States)

    Leenhouts, Robin

    2010-01-01

    This article describes a clay project for students studying Greece and Rome. It provides a wonderful way to learn slab construction techniques by making small clay column capitols. With this lesson, students learn architectural vocabulary and history, understand the importance of classical architectural forms and their influence on today's…

  20. Slender CRC Columns

    DEFF Research Database (Denmark)

    Aarup, Bendt; Jensen, Lars Rom; Ellegaard, Peter

    2005-01-01

    CRC is a high-performance steel fibre reinforced concrete with a typical compressive strength of 150 MPa. Design methods for a number of structural elements have been developed since CRC was invented in 1986, but the current project set out to further investigate the range of columns for which...

  1. Practical column design guide

    CERN Document Server

    Nitsche, M

    2017-01-01

    This book highlights the aspects that need to be considered when designing distillation columns in practice. It discusses the influencing parameters as well as the equations governing them, and presents several numerical examples. The book is intended both for experienced designers and for those who are new to the subject.

  2. Capillary Pumped Heat Transfer (CHT) Experiment

    Science.gov (United States)

    Hallinan, Kevin P.; Allen, J. S.

    1998-01-01

    The operation of Capillary Pumped Loops (CPL's) in low gravity has generally been unable to match ground-based performance. The reason for this poorer performance has been elusive. In order to investigate the behavior of a CPL in low-gravity, an idealized, glass CPL experiment was constructed. This experiment, known as the Capillary-driven Heat Transfer (CHT) experiment, was flown on board the Space Shuttle Columbia in July 1997 during the Microgravity Science Laboratory mission. During the conduct of the CHT experiment an unexpected failure mode was observed. This failure mode was a result of liquid collecting and then eventually bridging the vapor return line. With the vapor return line blocked, the condensate was unable to return to the evaporator and dry-out subsequently followed. The mechanism for this collection and bridging has been associated with long wavelength instabilities of the liquid film forming in the vapor return line. Analysis has shown that vapor line blockage in present generation CPL devices is inevitable. Additionally, previous low-gravity CPL tests have reported the presence of relatively low frequency pressure oscillations during erratic system performance. Analysis reveals that these pressure oscillations are in part a result of long wavelength instabilities present in the evaporator pores, which likewise lead to liquid bridging and vapor entrapment in the porous media. Subsequent evaporation to the trapped vapor increases the vapor pressure. Eventually the vapor pressure causes ejection of the bridged liquid. Recoil stresses depress the meniscus, the vapor pressure rapidly increases, and the heated surface cools. The process then repeats with regularity.

  3. Western blotting using capillary electrophoresis.

    Science.gov (United States)

    Anderson, Gwendolyn J; M Cipolla, Cynthia; Kennedy, Robert T

    2011-02-15

    A microscale Western blotting system based on separating sodium-dodecyl sulfate protein complexes by capillary gel electrophoresis followed by deposition onto a blotting membrane for immunoassay is described. In the system, the separation capillary is grounded through a sheath capillary to a mobile X-Y translation stage which moves a blotting membrane past the capillary outlet for protein deposition. The blotting membrane is moistened with a methanol and buffer mixture to facilitate protein adsorption. Although discrete protein zones could be detected, bands were broadened by ∼1.7-fold by transfer to membrane. A complete Western blot for lysozyme was completed in about one hour with 50 pg mass detection limit from low microgram per milliliter samples. These results demonstrate substantial reduction in time requirements and improvement in mass sensitivity compared to conventional Western blots. Western blotting using capillary electrophoresis shows promise to analyze low volume samples with reduced reagents and time, while retaining the information content of a typical Western blot.

  4. A SANS study of capillary condensation in porous media

    International Nuclear Information System (INIS)

    Lin, M.; Glinka, C.; Sinna, S.; Huang, J.; Abeles, B.; Johnson, J.; Drake, J.

    1990-01-01

    The authors use small angle neutron scattering (SANS) to study the microstructure of porous Vycor glass and the capillary condensation of fluids in the medium. Using a chord distribution model, they can predict the structure factor measured by SANS. Excellent agreement with the data is obtained. The fitted parameters characterize quantitatively the porous structure before and during the process of condensation, and are in good agreement with isotherm measurements. However, at the latest stages of the process, when all the pores are nearly filled, the model can no longer describe the system

  5. GLASS BOX

    National Research Council Canada - National Science Library

    Curtis, Laura

    2008-01-01

    The goals of this effort were to develop Glass Box capabilities to allow for the capturing of analyst activities and the associated data resources, track and log the results of automated processing...

  6. Impacts on oil recovery from capillary pressure and capillary heterogeneities

    Energy Technology Data Exchange (ETDEWEB)

    Bognoe, Thomas

    2008-07-01

    The main conclusions drawn from this thesis are; 7 scientific papers are published on a broad variety of subjects, and describes in detail the experiments and research treated in this thesis. Scientific research has been performed, investigating the subjects of capillary pressure and capillary heterogeneities from different angles. This thesis discusses the findings in this study and aims to illustrate the benefits of the results obtained for further development of other experiments, and/or even the industrial benefits in field development. The methods for wettability alteration have developed throughout the work. From producing heterogeneous wettability alterations, the methods have improved to giving both radial and lateral uniform wettability alterations, which also remains unaltered throughout the duration of the experimental work. The alteration of wettability is dependent on initial water saturation, flow rate, aging time and crude oil composition. Capillary pressure and relative permeability curves have been measured for core plugs at different wettabilities using conventional centrifuge methods. The trends observed are mostly consistent with theory. The production mechanisms of strongly and moderately water wet chalk has been investigated. At strongly water wet conditions in fractured chalk; the flow is governed by capillary forces, showing strong impact from the fractures. At moderately water wet conditions, the impact of the fractures are absent, and a dispersed water front is observed during the displacement. The oil recovery is about the same, at the two wettabilities. Fracture crossing mechanisms at the same wettability conditions have been mapped. And the observations are consistent with those of the water floods. During strongly water wet displacement, the fracture crossing is occurring once the inlet core has reached endpoint of spontaneous imbibition. At moderately water wet conditions the fracture crossing is less abrupt, and creation of wetting

  7. Escherichia coli adhesive coating as a chiral stationary phase for open tubular capillary electrochromatography enantioseparation

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Qifeng, E-mail: fuqifeng1990@163.com [Department of Medicinal Chemistry, Southwest Medical University, Luzhou 646000 (China); Zhang, Kailian; Gao, Die; Wang, Lujun [Department of Medicinal Chemistry, Southwest Medical University, Luzhou 646000 (China); Yang, Fengqing; Liu, Yao [School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400030 (China); Xia, Zhining, E-mail: tcm_anal_cqu@163.com [Innovative Drug Research Centre and School of Pharmaceutical Sciences, Chongqing University, Chongqing 400030 (China); School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400030 (China)

    2017-05-29

    Bacteria, the microorganism with intrinsic chirality, have numerous fascinating chiral phenomena such as various chirality-triggered biological processes and behaviors. Herein, bacteria were firstly explored as novel chiral stationary phases in open-tubular capillary electrochromatography (OT-CEC) for enantioseparation of fluoroquinolone enantiomers and simultaneous separation of six fluoroquinolone antibiotics. The model strain, i.e. non-pathogenic Escherichia coli (E. coli) DH5α, was adhered onto the inner surface of positively charged polyethyleneimine (PEI) modified capillaries based on the bacterial adhesion characteristics and strong electrostatic interaction. The morphology and thickness of the bacteria adhesive coatings in the capillary were characterized by field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). Baseline separation of ofloxacin and partial separation of lomefloxacin enantiomers could be achieved by the E. coli coated columns. The preparation parameters including the coating time and concentration of bacteria that affecting the chiral resolution were intensively investigated. The electrophoretic parameters, including pH, buffer concentration and applied voltage, were also optimized. The developed method was validated (linearity, LOD, LOQ, intra-day, inter-day and column-to-column repeatability and recovery) and successfully utilized for the quantitative analysis of ofloxacin enantiomers in the ofloxacin tablets. Moreover, only a slight decrease in the separation efficiency was observed after 90 consecutive runs on the E. coli@capillary. These results demonstrated that bacteria are promising stationary phases for chiral separation in CEC. - Highlights: • Bacteria were firstly introduced in OT-CEC as a chiral stationary phase for chiral separation. • Enantioseparation of ofloxacin enantiomers was achieved on E. coli coated open tubular capillary column. • Bacterial stationary phases may be used to

  8. Qualitative and quantitative analysis of cations and anions using ion selective detectors in capillary electrophoresis

    International Nuclear Information System (INIS)

    Nann, A.

    1994-01-01

    The present work reports on the application of ion-selective microelectrodes as potentiometric detectors for the qualitative and quantitative analysis of cations and anions separated by capillary electrophoresis. Due to the high internal resistance of microelectrodes, their potentials are strongly affected by external electrical fields. Therefore, the influence of the electrophoretic field on the electrode response had to be kept at a minimum. With the electrode tip inserted in the capillary aperture (on-column detection), heavy drifts and noise of the signals were observed, mainly because the electrophoretic potential is superimposed on the Nernstian electrode response. As the potential inside the capillary is site-dependent, already minor movements and vibrations not perceptible under the light microscopy cause unacceptable disturbances of the electrode signal. One possibility to solve the problem consists in post- or off-column detection, i.e., with the detector located outside the influence of the electrophoretic field. If quantitative analyses with maximum resolution are to be achieved, only on-column detection is suitable because outside the capillary, the separation efficiency drops drastically. By etching the detector-side capillary end to a conical aperture, the field strength in the last 10 μm fell approximately 1/25 as compared with that in a cylindrical one. Thus, potential drifts and noise were reduced correspondingly so that on-column detection can also be used for potentiometric detection. To obtain quantitative results, the signals of the ion-selective detector were first delogarithmized and then integrated over time. Thus, it was possible to quantify cations and anions with a coefficient of variations ≤5%. (author) figs., tabs., 179 refs

  9. Escherichia coli adhesive coating as a chiral stationary phase for open tubular capillary electrochromatography enantioseparation

    International Nuclear Information System (INIS)

    Fu, Qifeng; Zhang, Kailian; Gao, Die; Wang, Lujun; Yang, Fengqing; Liu, Yao; Xia, Zhining

    2017-01-01

    Bacteria, the microorganism with intrinsic chirality, have numerous fascinating chiral phenomena such as various chirality-triggered biological processes and behaviors. Herein, bacteria were firstly explored as novel chiral stationary phases in open-tubular capillary electrochromatography (OT-CEC) for enantioseparation of fluoroquinolone enantiomers and simultaneous separation of six fluoroquinolone antibiotics. The model strain, i.e. non-pathogenic Escherichia coli (E. coli) DH5α, was adhered onto the inner surface of positively charged polyethyleneimine (PEI) modified capillaries based on the bacterial adhesion characteristics and strong electrostatic interaction. The morphology and thickness of the bacteria adhesive coatings in the capillary were characterized by field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). Baseline separation of ofloxacin and partial separation of lomefloxacin enantiomers could be achieved by the E. coli coated columns. The preparation parameters including the coating time and concentration of bacteria that affecting the chiral resolution were intensively investigated. The electrophoretic parameters, including pH, buffer concentration and applied voltage, were also optimized. The developed method was validated (linearity, LOD, LOQ, intra-day, inter-day and column-to-column repeatability and recovery) and successfully utilized for the quantitative analysis of ofloxacin enantiomers in the ofloxacin tablets. Moreover, only a slight decrease in the separation efficiency was observed after 90 consecutive runs on the E. coli@capillary. These results demonstrated that bacteria are promising stationary phases for chiral separation in CEC. - Highlights: • Bacteria were firstly introduced in OT-CEC as a chiral stationary phase for chiral separation. • Enantioseparation of ofloxacin enantiomers was achieved on E. coli coated open tubular capillary column. • Bacterial stationary phases may be used to

  10. Genetic variability of Artemisia capillaris (Wormwood capillary) by ...

    African Journals Online (AJOL)

    The genetic variability among individuals of Artemisia capillaris from state of Terengganu, Malaysia was examined by using the random amplified polymorphic DNA (RAPD) technique. The samples were collected from differences regional in Terengganu State. The genomic DNA was extracted from the samples leaves.

  11. Nine Words - Nine Columns

    DEFF Research Database (Denmark)

    Trempe Jr., Robert B.; Buthke, Jan

    2016-01-01

    This book records the efforts of a one-week joint workshop between Master students from Studio 2B of Arkitektskolen Aarhus and Master students from the Harbin Institute of Technology in Harbin, China. The workshop employed nine action words to instigate team-based investigation into the effects o...... as formwork for the shaping of wood veneer. The resulting columns ‘wear’ every aspect of this design pipeline process and display the power of process towards an architectural resolution....

  12. NMFS Water Column Sonar Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water column sonar data are an important component of fishery independent surveys, habitat studies and other research. NMFS water column sonar data are archived here.

  13. 3D capillary valves for versatile capillary patterning of channel walls

    NARCIS (Netherlands)

    Papadimitriou, Vasileios; van den Berg, Albert; Eijkel, Jan C.T.

    2016-01-01

    We demonstrate passive capillary patterning of channel walls with a liquid in situ. Patterning is performed using a novel 3D capillary valve system combining three standard capillary stop valves. A range of different patterns is demonstrated in three channel walls. Capillary patterning was designed

  14. Capillary thinning of polymeric filaments

    DEFF Research Database (Denmark)

    Kolte, Mette Irene; Szabo, Peter

    1999-01-01

    The capillary thinning of filaments of a Newtonian polybutene fluid and a viscoelastic polyisobutylene solution are analyzed experimentally and by means of numerical simulation. The experimental procedure is as follows. Initially, a liquid sample is placed between two cylindrical plates. Then, th...

  15. Vacuum scanning capillary photoemission microscopy.

    Science.gov (United States)

    Aseyev, S A; Cherkun, A P; Mironov, B N; Petrunin, V V; Chekalin, S V

    2017-08-01

    We demonstrate the use of a conical capillary in a scanning probe microscopy for surface analysis. The probe can measure photoemission from a substrate by transmitting photoelectrons along the capillary as a function of probe position. The technique is demonstrated on a model substrate consisting of a gold reflecting layer on a compact disc which has been illuminated by an unfocused laser beam with a wavelength 400nm, from a femtosecond laser with a beam size of 4mm. A quartz capillary with a 2-µm aperture has been used in the experiments. The period of gold microstructure, shown to be 1.6µ, was measured by the conical probe operating in shear force mode. In shear force regime, the dielectric capillary has been used as a "classical" SPM tip, which provided images reflecting the surface topology. In a photoelectron regime photoelectrons passed through hollow tip and entered a detector. The spatial distribution of the recorded photoelectrons consisted of periodic mountain-valley strips, resembling the surface profile of the sample. Submicron spatial resolution has been achieved. This approach paves the way to study pulsed photodesorption of large organic molecular ions with high spatial and element resolution using the combination of a hollow-tip scanner with time-of-flight technique. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Capillary Sharp Inner Edge Manufacturing

    Czech Academy of Sciences Publication Activity Database

    Hošek, Jan; Studenovský, K.; Najdek, D.

    2009-01-01

    Roč. 19, č. 35 (2009), s. 19-25 ISSN 1584-5982. [MECAHITECH 09 /1./. Bukurešť, 08.10.2009-09.10.2009] R&D Projects: GA AV ČR IAA200760905 Institutional research plan: CEZ:AV0Z20760514 Keywords : capillary * edge * manufacturing Subject RIV: JR - Other Machinery

  17. Analytical characterization of wine and its precursors by capillary electrophoresis.

    Science.gov (United States)

    Gomez, Federico J V; Monasterio, Romina P; Vargas, Verónica Carolina Soto; Silva, María F

    2012-08-01

    The accurate determination of marker chemical species in grape, musts, and wines presents a unique analytical challenge with high impact on diverse areas of knowledge such as health, plant physiology, and economy. Capillary electromigration techniques have emerged as a powerful tool, allowing the separation and identification of highly polar compounds that cannot be easily separated by traditional HPLC methods, providing complementary information and permitting the simultaneous analysis of analytes with different nature in a single run. The main advantage of CE over traditional methods for wine analysis is that in most cases samples require no treatment other than filtration. The purpose of this article is to present a revision on capillary electromigration methods applied to the analysis of wine and its precursors over the last decade. The current state of the art of the topic is evaluated, with special emphasis on the natural compounds that have allowed wine to be considered as a functional food. The most representative revised compounds are phenolic compounds, amino acids, proteins, elemental species, mycotoxins, and organic acids. Finally, a discussion on future trends of the role of capillary electrophoresis in the field of analytical characterization of wines for routine analysis, wine classification, as well as multidisciplinary aspects of the so-called "from soil to glass" chain is presented. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Glass compositions

    Energy Technology Data Exchange (ETDEWEB)

    France, P W

    1985-05-30

    A fluoride glass for use in the production of optical fibres has an enhanced D/H ratio, preferably such that OD:OH is at least 9:1. In the example, such a glass is prepared by treating with D/sub 2/O a melt comprising 51.53 mole per cent ZrF/sub 4/, 20.47 mole per cent BaF/sub 2/, 5.27 mole per cent LaF/sub 3/, 3.24 mole per cent AlF/sub 3/, and 19.49 mole per cent LiF.

  19. Elevator frames two columns

    OpenAIRE

    Marín Jiménez, Juan Francisco

    2015-01-01

    This project aims to solve the problem of vertical transport of charges raised by a company with the standard UNE 58-132-91/6. The purpose of this project is the industrial design of a system of load handling by a bi-columned lifting device, tractioned by flat belts and steel cables from a transport level to a different level in order to connect two different assembly lines situated at different heights. The goal of this project is lifting a 780 Kg load at a 2.400 mm height....

  20. Column: Every Last Byte

    Directory of Open Access Journals (Sweden)

    Simson Garfinkel

    2011-06-01

    Full Text Available Inheritance powder is the name that was given to poisons, especially arsenic, that were commonly used in the 17th and early 18th centuries to hasten the death of the elderly. For most of the 17th century, arsenic was deadly but undetectable, making it nearly impossible to prove that someone had been poisoned. The first arsenic test produced a gas—hardly something that a scientist could show to a judge. Faced with a growing epidemic of poisonings, doctors and chemists spent decades searching for something better.(see PDF for full column

  1. Preparation of chitosan-graft-(β-cyclodextrin) based sol-gel stationary phase for open-tubular capillary electrochromatography.

    Science.gov (United States)

    Lü, Haixia; Li, Qingyin; Yu, Xiaowei; Yi, Jiaojiao; Xie, Zenghong

    2013-07-01

    A novel open-tubular CEC column coated with chitosan-graft-(β-CD) (CDCS) was prepared using sol-gel technique. In the sol-gel approach, owing to the 3D network of sol-gel and the strong chemical bond between the stationary phase and the surface of capillary columns, good chromatographic characteristics and unique selectivity in separating isomers were shown. The column efficiencies of 55,000∼163,000 plates/m for the isomeric xanthopterin and phenoxy acid herbicides using the sol-gel-derived CDCS columns were achieved. Good stabilities were demonstrated that the RSD values for the retention time of thiourea and isoxanthopterin were 1.3 and 1.4% (run to run, n = 5), 1.6 and 2.0% (day to day, n = 3), 2.9 and 3.1% (column to column, n = 3), respectively. The sol-gel-coated CDCS columns have shown improved separations of isomeric xanthopterin in comparison with CDCS-bonded capillary column. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. On-line combination of liquid chromatography and capillary gas chromatography : preconcentration and analysis of organic compounds in aqueous samples

    NARCIS (Netherlands)

    Noij, T.H.M.; Weiss, E.; Herps, T.; Cruchten, van H.; Rijks, J.A.

    1988-01-01

    This paper describes the design of a new, versatile, and low-cost on-line LC-GC interface that allows the fast and reliable introduction of large sample volumes onto a capillary GC column. The sample introduction procedure consists successively of: evaporation of the entire sample (LC fraction),

  3. Phosphatidylcholine covalently linked to a methacrylate-based monolith as a biomimetic stationary phase for capillary liquid chromatography

    Czech Academy of Sciences Publication Activity Database

    Moravcová, Dana; Carrasco-Correa, E. J.; Planeta, Josef; Lämmerhofer, M.; Wiedmer, S. K.

    2015-01-01

    Roč. 1402, JUL (2015), s. 27-35 ISSN 0021-9673 R&D Projects: GA MV VG20112015021 Institutional support: RVO:68081715 Keywords : Capillary LC * analyte–membrane interaction * monolithic column * phospholipids Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.926, year: 2015 http://hdl.handle.net/11104/0247268

  4. Jurin's law revisited: Exact meniscus shape and column height.

    Science.gov (United States)

    Liu, Sai; Li, Shanpeng; Liu, Jianlin

    2018-03-30

    Capillary rise of a liquid column is a historical problem, which has normally been formulated by Jurin's law. In the present study, we investigate the exact solutions of the column height, considering the real shape of the meniscus according to the Young-Laplace equation. The analytical solution in the planar model and the numerical solution in the axisymmetric model on the meniscus shape are both given, which are compared with the results from Jurin's law, modified Jurin's law and Surface Evolver simulation. The results quantitatively show that when the distance between the two plates or the diameter of the tube becomes bigger, Jurin's law and modified Jurin's law would cause serious errors, and the profile morphology of the meniscus must be calculated according to the Young-Laplace equation. These findings are beneficial for us to better understand the mechanism of capillarity and wetting, which are promising for such areas as oil displacement, ore floatation, building materials, fabrics, etc.

  5. Mixed Capillary Venous Retroperitoneal Hemangioma

    Directory of Open Access Journals (Sweden)

    Mohit Godar

    2013-01-01

    Full Text Available We report a case of mixed capillary venous hemangioma of the retroperitoneum in a 61-year-old man. Abdominal ultrasonography showed a mass to be hypoechoic with increased flow in color Doppler imaging. Dynamic contrast-enhanced computed tomography revealed a centripetal filling-in of the mass, located anterior to the left psoas muscle at the level of sacroiliac joint. On the basis of imaging features, preoperative diagnosis of hemangioma was considered and the mass was excised by laparoscopic method. Immunohistochemical studies were strongly positive for CD31 and CD34, and negative for calretinin, EMA, WT1, HMB45, Ki67, synaptophysin, and lymphatic endothelial cell marker D2–40. Histologically, the neoplasm was diagnosed as mixed capillary venous hemangioma.

  6. Capillary waves with surface viscosity

    Science.gov (United States)

    Shen, Li; Denner, Fabian; Morgan, Neal; van Wachem, Berend; Dini, Daniele

    2017-11-01

    Experiments over the last 50 years have suggested a correlation between the surface (shear) viscosity and the stability of a foam or emulsion. With recent techniques allowing more accurate measurements of the elusive surface viscosity, we examine this link theoretically using small-amplitude capillary waves in the presence of the Marangoni effect and surface viscosity modelled via the Boussinesq-Scriven model. The surface viscosity effect is found to contribute a damping effect on the amplitude of the capillary wave with subtle differences to the effect of the convective-diffusive Marangoni transport. The general wave dispersion is augmented to take into account the Marangoni and surface viscosity effects, and a first-order correction to the critical damping wavelength is derived. The authors acknowledge the financial support of the Shell University Technology Centre for fuels and lubricants.

  7. Biodegradation of phenol, salicylic acid, benzenesulfonic acid, and iomeprol by Pseudomonas fluorescens in the capillary fringe.

    Science.gov (United States)

    Hack, Norman; Reinwand, Christian; Abbt-Braun, Gudrun; Horn, Harald; Frimmel, Fritz H

    2015-12-01

    Mass transfer and biological transformation phenomena in the capillary fringe were studied using phenol, salicylic acid, benzenesulfonic acid, and the iodinated X-ray contrast agent iomeprol as model organic compounds and the microorganism strain Pseudomonas fluorescens. Three experimental approaches were used: Batch experiments (uniform water saturation and transport by diffusion), in static columns (with a gradient of water saturation and advective transport in the capillaries) and in a flow-through cell (with a gradient of water saturation and transport by horizontal and vertical flow: 2-dimension flow-through microcosm). The reactors employed for the experiments were filled with quartz sand of defined particle size distribution (dp=200...600 μm, porosity ε=0.42). Batch experiments showed that phenol and salicylic acid have a high, whereas benzenesulfonic acid and iomeprol have a quite low potential for biodegradation under aerobic conditions and in a matrix nearly close to water saturation. Batch experiments under anoxic conditions with nitrate as electron acceptor revealed that the biodegradation of the model compounds was lower than under aerobic conditions. Nevertheless, the experiments showed that the moisture content was also responsible for an optimized transport in the liquid phase of a porous medium. Biodegradation in the capillary fringe was found to be influenced by both the moisture content and availability of the dissolved substrate, as seen in static column experiments. The gas-liquid mass transfer of oxygen also played an important role for the biological activity. In static column experiments under aerobic conditions, the highest biodegradation was found in the capillary fringe (e.g. βt/β0 (phenol)=0 after t=6 d) relative to the zone below the water table and unsaturated zone. The highest biodegradation occurred in the flow-through cell experiment where the height of the capillary fringe was largest. Copyright © 2015 Elsevier B.V. All rights

  8. Capillary Refill using Augmented Reality

    OpenAIRE

    Clausen, Christoffer

    2017-01-01

    Master's thesis in Computer science The opportunities within augmented reality is growing. Augmented reality is a combination of the real and the virtual world in real time, and large companies like Microsoft and Google is now investing heavily in the technology. This thesis presents a solution for simulating a medical test called capillary refill, by using augmented reality. The simulation is performed with an augmented reality headset called HoloLens. The HoloLens will recognise a mark...

  9. Capillary electrophoresis systems and methods

    Science.gov (United States)

    Dorairaj, Rathissh [Hillsboro, OR; Keynton, Robert S [Louisville, KY; Roussel, Thomas J [Louisville, KY; Crain, Mark M [Georgetown, IN; Jackson, Douglas J [New Albany, IN; Walsh, Kevin M [Louisville, KY; Naber, John F [Goshen, KY; Baldwin, Richard P [Louisville, KY; Franco, Danielle B [Mount Washington, KY

    2011-08-02

    An embodiment of the invention is directed to a capillary electrophoresis apparatus comprising a plurality of separation micro-channels. A sample loading channel communicates with each of the plurality of separation channels. A driver circuit comprising a plurality of electrodes is configured to induce an electric field across each of the plurality of separation channels sufficient to cause analytes in the samples to migrate along each of the channels. The system further comprises a plurality of detectors configured to detect the analytes.

  10. π-Extended triptycene-based material for capillary gas chromatographic separations.

    Science.gov (United States)

    Yang, Yinhui; Wang, Qinsi; Qi, Meiling; Huang, Xuebin

    2017-10-02

    Triptycene-based materials feature favorable physicochemical properties and unique molecular recognition ability that offer good potential as stationary phases for capillary gas chromatography (GC). Herein, we report the investigation of utilizing a π-extended triptycene material (denoted as TQPP) for GC separations. As a result, the TQPP capillary column exhibited high column efficiency of 4030 plates m -1 and high-resolution performance for a wide range of analytes, especially structural and positional isomers. Interestingly, the TQPP stationary phase showed unique shape selectivity for alkanes isomers and preferential retention for analytes with halogen atoms and H-bonding nature mainly through their halogen-bonding and H-bonding interactions. In addition, the TQPP column had good repeatability and reproducibility with the RSD values of 0.02-0.34% for run-to-run, 0.09-0.80% for day-to-day and 1.4-5.2% for column-to-column, respectively, and favorable thermal stability up to 280 °C. This work demonstrates the promising future of triptycene-based materials as a new class of stationary phases for GC separations. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Glass: Rotary Electric Glass Furnace

    Energy Technology Data Exchange (ETDEWEB)

    Recca, L.

    1999-01-29

    Compared to conventional gas-fired furnaces, the new rotary electric furnace will increase energy efficiency while significantly reducing air emissions, product turnaround time, and labor costs. As this informative new fact sheet explains, the thousand different types of glass optical blanks produced for the photonics industry are used for lasers, telescopes, cameras, lights, and many other products.

  12. Column-to-column packing variation of disposable pre-packed columns for protein chromatography.

    Science.gov (United States)

    Schweiger, Susanne; Hinterberger, Stephan; Jungbauer, Alois

    2017-12-08

    In the biopharmaceutical industry, pre-packed columns are the standard for process development, but they must be qualified before use in experimental studies to confirm the required performance of the packed bed. Column qualification is commonly done by pulse response experiments and depends highly on the experimental testing conditions. Additionally, the peak analysis method, the variation in the 3D packing structure of the bed, and the measurement precision of the workstation influence the outcome of qualification runs. While a full body of literature on these factors is available for HPLC columns, no comparable studies exist for preparative columns for protein chromatography. We quantified the influence of these parameters for commercially available pre-packed and self-packed columns of disposable and non-disposable design. Pulse response experiments were performed on 105 preparative chromatography columns with volumes of 0.2-20ml. The analyte acetone was studied at six different superficial velocities (30, 60, 100, 150, 250 and 500cm/h). The column-to-column packing variation between disposable pre-packed columns of different diameter-length combinations varied by 10-15%, which was acceptable for the intended use. The column-to-column variation cannot be explained by the packing density, but is interpreted as a difference in particle arrangement in the column. Since it was possible to determine differences in the column-to-column performance, we concluded that the columns were well-packed. The measurement precision of the chromatography workstation was independent of the column volume and was in a range of±0.01ml for the first peak moment and±0.007 ml 2 for the second moment. The measurement precision must be considered for small columns in the range of 2ml or less. The efficiency of disposable pre-packed columns was equal or better than that of self-packed columns. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  13. Capillaries modified by noncovalent anionic polymer adsorption for capillary zone electrophoresis, micellar electrokinetic capillary chromatography and capillary electrophoresis mass spectrometry

    DEFF Research Database (Denmark)

    Bendahl, L; Hansen, S H; Gammelgaard, Bente

    2001-01-01

    A simple coating procedure for generation of a high and pH-independent electroosmotic flow in capillary zone electrophoresis (CZE) and micellar electrokinetic capillary chromatography (MEKC) is described. The bilayer coating was formed by noncovalent adsorption of the ionic polymers Polybrene...... capillaries was (4.9+/-0.1) x 10(-4) cm2V(-1)s(-1) in a pH-range of 2-10 (ionic strength = 30 mM). When alkaline compounds were used as test substances intracapillary and intercapillary migration time variations (n = 6) were less than 1% relative standard deviation (RSD) and 2% RSD, respectively in the entire...... pH range. The coating was fairly stable in the presence of sodium dodecyl sulfate, and this made it possible to perform fast MEKC separations at low pH. When neutral compounds were used as test substances, the intracapillary migration time variations (n = 6) were less than 2% RSD in a pH range of 2...

  14. Column: File Cabinet Forensics

    Directory of Open Access Journals (Sweden)

    Simson Garfinkel

    2011-12-01

    Full Text Available Researchers can spend their time reverse engineering, performing reverse analysis, or making substantive contributions to digital forensics science. Although work in all of these areas is important, it is the scientific breakthroughs that are the most critical for addressing the challenges that we face.Reverse Engineering is the traditional bread-and-butter of digital forensics research. Companies like Microsoft and Apple deliver computational artifacts (operating systems, applications and phones to the commercial market. These artifacts are bought and used by billions. Some have evil intent, and (if society is lucky, the computers end up in the hands of law enforcement. Unfortunately the original vendors rarely provide digital forensics tools that make their systems amenable to analysis by law enforcement. Hence the need for reverse engineering.(see PDF for full column

  15. Development of novel separation techniques for biological samples in capillary electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Huan -Tsung [Iowa State Univ., Ames, IA (United States)

    1994-07-27

    This dissertation includes three different topics: general introduction of capillary electrophoresis (CE); gradient in CE and CE in biological separations; and capillary gel electrophoresis (CGE) for DNA separation. Factors such as temperature, viscosity, pH, and the surface of capillary walls affecting the separation performance are demonstrated. A pH gradient between 3.0 and 5.2 is useful to improve the resolution among eight different organic acids. A flow gradient due to the change in the concentration of surfactant, which is able to coat to the capillary wall to change the flow rate and its direction, is also shown as a good way to improve the resolution for organic compounds. A temperature gradient caused by joule heat is shown by voltage programming to enhance the resolution and shorten the separation time for several phenolic compounds. The author also shows that self-regulating dynamic control of electroosmotic flow in CE by simply running separation in different concentrations of surfactant has less matrix effect on the separation performance. One of the most important demonstrations in this dissertation is that the author proposes on-column reaction which gives several advantages including the use of a small amount of sample, low risk of contamination, and time saving and kinetic features. The author uses this idea with laser induced fluorescence (LIF) as a detection mode to detect an on-column digestion of sub-ng of protein. This technique also is applied to single cell analysis in the group.

  16. Progression of Diabetic Capillary Occlusion: A Model.

    Directory of Open Access Journals (Sweden)

    Xiao Fu

    2016-06-01

    Full Text Available An explanatory computational model is developed of the contiguous areas of retinal capillary loss which play a large role in diabetic maculapathy and diabetic retinal neovascularization. Strictly random leukocyte mediated capillary occlusion cannot explain the occurrence of large contiguous areas of retinal ischemia. Therefore occlusion of an individual capillary must increase the probability of occlusion of surrounding capillaries. A retinal perifoveal vascular sector as well as a peripheral retinal capillary network and a deleted hexagonal capillary network are modelled using Compucell3D. The perifoveal modelling produces a pattern of spreading capillary loss with associated macular edema. In the peripheral network, spreading ischemia results from the progressive loss of the ladder capillaries which connect peripheral arterioles and venules. System blood flow was elevated in the macular model before a later reduction in flow in cases with progression of capillary occlusions. Simulations differing only in initial vascular network structures but with identical dynamics for oxygen, growth factors and vascular occlusions, replicate key clinical observations of ischemia and macular edema in the posterior pole and ischemia in the retinal periphery. The simulation results also seem consistent with quantitative data on macular blood flow and qualitative data on venous oxygenation. One computational model applied to distinct capillary networks in different retinal regions yielded results comparable to clinical observations in those regions.

  17. Fluid Delivery System For Capillary Electrophoretic Applications.

    Science.gov (United States)

    Li, Qingbo; Liu, Changsheng; Kane, Thomas E.; Kernan, John R.; Sonnenschein, Bernard; Sharer, Michael V.

    2002-04-23

    An automated electrophoretic system is disclosed. The system employs a capillary cartridge having a plurality of capillary tubes. The cartridge has a first array of capillary ends projecting from one side of a plate. The first array of capillary ends are spaced apart in substantially the same manner as the wells of a microtitre tray of standard size. This allows one to simultaneously perform capillary electrophoresis on samples present in each of the wells of the tray. The system includes a stacked, dual carrousel arrangement to eliminate cross-contamination resulting from reuse of the same buffer tray on consecutive executions from electrophoresis. The system also has a gel delivery module containing a gel syringe/a stepper motor or a high pressure chamber with a pump to quickly and uniformly deliver gel through the capillary tubes. The system further includes a multi-wavelength beam generator to generate a laser beam which produces a beam with a wide range of wavelengths. An off-line capillary reconditioner thoroughly cleans a capillary cartridge to enable simultaneous execution of electrophoresis with another capillary cartridge. The streamlined nature of the off-line capillary reconditioner offers the advantage of increased system throughput with a minimal increase in system cost.

  18. Nitrate glass

    International Nuclear Information System (INIS)

    Kirilenko, I.A.; Vinogradov, E.E.

    1977-01-01

    Experimental evidence on behaviour of nitrate glasses is reviewed in terms of relationships between the presence of water in vitrescent nitrate systems and the properties of the systems. The glasses considered belong to systems of Mg(NO 3 ) 2 - Nd(NO 3 ) 3 ; Hg(NO 3 ) 2 -Nd(NO 3 ) 3 ; NaNO 3 -Mg(NO 3 ) 2 -Nd(NO 3 ) 3 ; M-Zn(NO 3 ) 3 , where M is a mixture of 20% mass NaNO 3 and 80% mass Mg(NO 3 ) 2 , and Zn is a rare earth ion. Nitrate glass is shown to be a product of dehydration. Vitrification may be regarded as a resusl of formation of molecular complexes in the chain due to hydrogen bonds of two types, i.e. water-water, or water-nicrate group. Chain formation, along with low melting points of the nitrates, hinder crystallization of nitrate melts. Provided there is enough water, this results in vitrification

  19. Compact electron beam focusing column

    Science.gov (United States)

    Persaud, Arun; Leung, Ka-Ngo; Reijonen, Jani

    2001-12-01

    A novel design for an electron beam focusing column has been developed at LBNL. The design is based on a low-energy spread multicusp plasma source which is used as a cathode for electron beam production. The focusing column is 10 mm in length. The electron beam is focused by means of electrostatic fields. The column is designed for a maximum voltage of 50 kV. Simulations of the electron trajectories have been performed by using the 2D simulation code IGUN and EGUN. The electron temperature has also been incorporated into the simulations. The electron beam simulations, column design and fabrication will be discussed in this presentation.

  20. Efficient compression of the femtosecond pulses of an ytterbium laser in a gas-filled capillary

    International Nuclear Information System (INIS)

    Konyashchenko, Aleksandr V; Losev, Leonid L; Tenyakov, S Yu

    2011-01-01

    A 290-fs radiation pulse of an ytterbium laser system with a central wavelength of 1028 nm and an energy of 145 μJ was compressed to a 27-fs pulse with an energy of 75 μJ. The compression was realised on the basis of the effect of pulse spectrum broadening in a xenon-filled glass capillary for a pulse repetition rate of 3kHz. (control of laser radiation parameters)

  1. Capillary pumped loop body heat exchanger

    Science.gov (United States)

    Swanson, Theodore D. (Inventor); Wren, deceased, Paul (Inventor)

    1998-01-01

    A capillary pumped loop for transferring heat from one body part to another body part, the capillary pumped loop comprising a capillary evaporator for vaporizing a liquid refrigerant by absorbing heat from a warm body part, a condenser for turning a vaporized refrigerant into a liquid by transferring heat from the vaporized liquid to a cool body part, a first tube section connecting an output port of the capillary evaporator to an input of the condenser, and a second tube section connecting an output of the condenser to an input port of the capillary evaporator. A wick may be provided within the condenser. A pump may be provided between the second tube section and the input port of the capillary evaporator. Additionally, an esternal heat source or heat sink may be utilized.

  2. Non-aqueous electrolytes for isotachophoresis of weak bases and its application to the comprehensive preconcentration of the 20 proteinogenic amino acids in column-coupling ITP/CE-MS.

    Science.gov (United States)

    Kler, Pablo A; Huhn, Carolin

    2014-11-01

    Isotachophoresis (ITP) has long been used alone but also as a preconcentration technique for capillary electrophoresis (CE). Unfortunately, up to now, its application is restricted to relatively strong acids and bases as either the degree of (de)protonation is too low or the water dissociation is too high, evoking zone electrophoresis. With the comprehensive ITP analysis of all 20 proteinogenic amino acids as model analytes, we, here, show that non-aqueous ITP using dimethylsulfoxide as a solvent solves this ITP shortcoming. Dimethylsulfoxide changes the pH regime of analytes and electrolytes but, more importantly, strongly reduces the proton mobility by prohibiting hydrogen bonds and thus, the so-called Zundel-Eigen-Zundel electrical conduction mechanism of flipping hydrogen bonds. The effects are demonstrated in an electrolyte system with taurine or H(+) as terminator, and imidazole as leader together with strong acids such as oxalic and even trifluoroacetic acid as counterions, both impossible to use in aqueous solution. Mass spectrometric as well as capacitively coupled contactless conductivity detection (C(4)D) are used to follow the ITP processes. To demonstrate the preconcentration capabilities of ITP in a two-dimensional set-up, we, here, also demonstrate that our non-aqueous ITP method can be combined with capillary electrophoresis-mass spectrometry in a column-coupling system using a hybrid approach of capillaries coupled to a microfluidic interface. For this, C(4)D was optimized for on-chip detection with the electrodes aligned on top of a thin glass lid of the microfluidic chip.

  3. Intracranial capillary hemangioma mimicking a dissociative disorder

    Directory of Open Access Journals (Sweden)

    Alexander Lacasse

    2012-01-01

    Full Text Available Capillary hemangiomas, hamartomatous proliferation of vascular endothelial cells, are rare in the central nervous system (CNS. Intracranial capillary hemangiomas presenting with reversible behavioral abnormalities and focal neurological deficits have rarely been reported. We report a case of CNS capillary hemangioma presenting with transient focal neurological deficits and behavioral abnormalities mimicking Ganser’s syndrome. Patient underwent total excision of the vascular malformation, resulting in complete resolution of his symptoms.

  4. Capillary condensation between disks in two dimensions

    OpenAIRE

    Gil, Tamir; Ipsen, John Hjorth

    1997-01-01

    Capillary condensation between two two-dimensional wetted circular substrates (disks) is studied by an effective free energy description of the wetting interface. The interfacial free-energy potential is developed on the basis of the theory for the wetting of a single disk, where interfacial capillary fluctuations play a dominant role. A simple approximative analytical expression of the interfacial free energy is developed and is validated numerically. The capillary condensation is characteri...

  5. Application of capillary electrophoresis to anion speciation in soil water extracts: 2. Arsenic

    Energy Technology Data Exchange (ETDEWEB)

    Naidu, R.; Smith, J.; McLaren, R.G.; Stevens, D.P.; Sumner, M.E.; Jackson, P.E.

    2000-02-01

    A method has been developed for the speciation of arsenic (AsO{sub 2}{sup {minus}}, AsO{sub 4}{sup 3{minus}}, and dimethylarsinic [DMA]) in natural soil solutions from contaminated sites in Australia. The separation of these anions was achieved by capillary zone electrophoresis (CZE) using a fused silica capillary with a basic chromate buffer and on-column indirect UV detection at 254 nm. Method parameters, such as electrolyte pH, run voltage, and capillary temperature were studied in order to establish suitable analytical conditions. The ideal separation for As(III) and DMA was achieved with a buffer pH of 8.0, a run voltage of 25 kV, and a capillary temperature of 30 C. Under these conditions, As(V) and orthophosphate ions comigrated. However, the use of a chromate buffer at pH 10, a run voltage of 20 kV, and capillary temperature of 20 C led to complete separation of As(V) and phosphate peaks. Results of these investigations together with recovery test data suggest that separation of the As species from soil solutions can be achieved in less than 5 min with detection limits of 0.50, 0.10, and 0.10 mg L{sup {minus}1} for As(III), As(V), and DMA, respectively.

  6. Exploitation of a microporous organic polymer as a stationary phase for capillary gas chromatography

    International Nuclear Information System (INIS)

    Lu, Cuiming; Liu, Shuqin; Xu, Jianqiao; Ding, Yajuan; Ouyang, Gangfeng

    2016-01-01

    Microporous organic polymers (MOPs) have emerged as a new class of functional porous materials with unique characteristics and potential uses in diverse areas. However, the field of MOPs for gas chromatographic (GC) separations has not been well explored. Herein, a MOP namely KAPs-1 was dynamic coated onto a capillary column for the first time. The fabricated column exhibited a nonpolar nature and the column efficiency for n-dodecane was up to 7769 plates m"−"1. The KAPs-1 coated column showed high GC separation performance for a series of volatile organic compounds (VOCs) including the challenging ethylbenzene and xylene isomers, which could not be resolved at baseline on the commercial 5% phenyl polysiloxane stationary phase. Moreover, the relative standard deviations for five replicate determinations of the studied analytes were 0.0–0.6%, 0.9–3.2%, 1.1–5.9%, 0.8–3.7% for retention time, peak area, peak height and peak width, respectively. To investigate the interaction between some analytes and the stationary phase, thermodynamic and kinetic parameters were also evaluated. The results of this study show it is very promising to utilize MOPs as stationary phases for capillary GC. - Highlights: • A microporous organic polymer was explored as a novel stationary phase for capillary GC. • The column showed high separation performance for VOCs including the challenging ethylbenzene and xylene isomers. • Thermodynamic and kinetic parameters for BTEXs were determined to study the analyte-stationary phase interaction.

  7. Exploitation of a microporous organic polymer as a stationary phase for capillary gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Cuiming; Liu, Shuqin; Xu, Jianqiao; Ding, Yajuan; Ouyang, Gangfeng, E-mail: cesoygf@mail.sysu.edu.cn

    2016-01-01

    Microporous organic polymers (MOPs) have emerged as a new class of functional porous materials with unique characteristics and potential uses in diverse areas. However, the field of MOPs for gas chromatographic (GC) separations has not been well explored. Herein, a MOP namely KAPs-1 was dynamic coated onto a capillary column for the first time. The fabricated column exhibited a nonpolar nature and the column efficiency for n-dodecane was up to 7769 plates m{sup −1}. The KAPs-1 coated column showed high GC separation performance for a series of volatile organic compounds (VOCs) including the challenging ethylbenzene and xylene isomers, which could not be resolved at baseline on the commercial 5% phenyl polysiloxane stationary phase. Moreover, the relative standard deviations for five replicate determinations of the studied analytes were 0.0–0.6%, 0.9–3.2%, 1.1–5.9%, 0.8–3.7% for retention time, peak area, peak height and peak width, respectively. To investigate the interaction between some analytes and the stationary phase, thermodynamic and kinetic parameters were also evaluated. The results of this study show it is very promising to utilize MOPs as stationary phases for capillary GC. - Highlights: • A microporous organic polymer was explored as a novel stationary phase for capillary GC. • The column showed high separation performance for VOCs including the challenging ethylbenzene and xylene isomers. • Thermodynamic and kinetic parameters for BTEXs were determined to study the analyte-stationary phase interaction.

  8. Capillary concentrators for synchrotron radiation beamlines

    International Nuclear Information System (INIS)

    Heald, S.M.; Brewe, D.L.; Kim, K.H.; Brown, F.C.; Barg, B.; Stern, E.A.

    1996-01-01

    Capillary concentrators condense x-rays by multiple reflections down a gradually tapering capillary. They can provide sub-micron beam spots, and are promising candidates for use in the next generation x-ray microprobe beamlines. The weak energy dependence of their properties make them especially useful for energy scanning applications such as micro-XAFS. This paper examines the potential performance of capillary optics for an x-ray microprobe, as well as some practical issues such as fabrication and alignment. Best performance at third generation sources requires long capillaries, and the authors have been using fiber optics techniques to fabricate capillaries up to one meter in length. The performance of shorter (less than about 0.5 m) capillaries has often been found to agree well with theoretical calculations, indicating the inner surface is a high quality x-ray reflector. These capillaries have been tested at the NSLS for imaging and micro-XAFS down to 2.6 microm resolution with excellent results. On an unfocused bend magnet line flux density approaching 10 6 ph/sec/microm 2 has been achieved. While nearly optimum profiles have been achieved for longer capillaries, the results have been disappointing, and alignment problems are suspected. The dramatic improvement in performance possible at third generation synchrotrons such as the APS is discussed along with improvements possible by using the capillaries in conjunction with coupling optics

  9. Slope wavenumber spectrum models of capillary and capillary-gravity waves

    Institute of Scientific and Technical Information of China (English)

    贾永君; 张杰; 王岩峰

    2010-01-01

    Capillary and capillary-gravity waves possess a random character, and the slope wavenumber spectra of them can be used to represent mean distributions of wave energy with respect to spatial scale of variability. But simple and practical models of the slope wavenumber spectra have not been put forward so far. In this article, we address the accurate definition of the slope wavenumber spectra of water surface capillary and capillary-gravity waves. By combining the existing slope wavenumber models and using th...

  10. Capillary electrophoresis and nanomaterials - Part I: Capillary electrophoresis of nanomaterials.

    Science.gov (United States)

    Adam, Vojtech; Vaculovicova, Marketa

    2017-10-01

    Nanomaterials are in analytical science used for a broad range of purposes, covering the area of sample pretreatment as well as separation, detection, and identification of target molecules. This part of the review covers capillary electrophoresis (CE) of nanomaterials and focuses on the application of CE as a method for characterization used during nanomaterial synthesis and modification as well as the monitoring of their properties and interactions with other molecules. The heterogeneity of the nanomaterial family is extremely large. Depending on different definitions of the term Nanomaterial/Nanoparticle, the group may cover metal and polymeric nanoparticles, carbon nanomaterials, liposomes and even dendrimers. Moreover, these nanomaterials are usually subjected to some kind of surface modification or functionalization, which broadens the diversity even more. Not only for purposes of verification of nanomaterial synthesis and batch-to-batch quality check, but also for determination the polydispersity and for functionality characterization on the nanoparticle surface, has CE offered very beneficial capabilities. Finally, the monitoring of interactions between nanomaterials and other (bio)molecules is easily performed by some kind of capillary electromigration technique. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Transmission properties of C60 ions through micro- and nano-capillaries

    International Nuclear Information System (INIS)

    Tsuchida, Hidetsugu; Majima, Takuya; Tomita, Shigeo; Sasa, Kimikazu; Narumi, Kazumasa; Saitoh, Yuichi; Chiba, Atsuya; Yamada, Keisuke; Hirata, Koichi; Shibata, Hiromi; Itoh, Akio

    2013-01-01

    We apply the capillary beam-focusing method for the C 60 fullerene projectiles in the velocity range between 0.14 and 0.2 a.u. We study the C 60 transmission properties through two different types of capillaries: (1) borosilicate glass microcapillary with an outlet diameter of 5.5 μm, and (2) Al 2 O 3 multi-capillary foil with a pore size of about 70 nm and a high aspect ratio of about 750. We measured the transmitted particle composition by using the electrostatic deflection method combined with the microchannel plate imaging technique. For the experiments with the single microcapillary, the main transmission component is found to be primary C 60 beams that are focused in the area equal to the capillary outlet diameter. Minor components are charge-exchanged C 60 ions and charged or neutral fragments (fullerene-like C 60-2m and small C n particles), and their fractions decrease with decreasing the projectile velocity. It is concluded that the C 60 transmission fraction is considerably high for both types of the capillaries in the present velocity range

  12. Transmission properties of C{sub 60} ions through micro- and nano-capillaries

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchida, Hidetsugu, E-mail: tsuchida@nucleng.kyoto-u.ac.jp [Quantum Science and Engineering Center, Kyoto University, Uji, Kyoto 611-0011 (Japan); Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Majima, Takuya [Quantum Science and Engineering Center, Kyoto University, Uji, Kyoto 611-0011 (Japan); Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Tomita, Shigeo [Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Sasa, Kimikazu [Tandem Accelerator Complex, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Narumi, Kazumasa; Saitoh, Yuichi; Chiba, Atsuya; Yamada, Keisuke [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, Takasaki, Gunma 370-1292 (Japan); Hirata, Koichi [National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8565 (Japan); Shibata, Hiromi [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Itoh, Akio [Quantum Science and Engineering Center, Kyoto University, Uji, Kyoto 611-0011 (Japan); Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan)

    2013-11-15

    We apply the capillary beam-focusing method for the C{sub 60} fullerene projectiles in the velocity range between 0.14 and 0.2 a.u. We study the C{sub 60} transmission properties through two different types of capillaries: (1) borosilicate glass microcapillary with an outlet diameter of 5.5 μm, and (2) Al{sub 2}O{sub 3} multi-capillary foil with a pore size of about 70 nm and a high aspect ratio of about 750. We measured the transmitted particle composition by using the electrostatic deflection method combined with the microchannel plate imaging technique. For the experiments with the single microcapillary, the main transmission component is found to be primary C{sub 60} beams that are focused in the area equal to the capillary outlet diameter. Minor components are charge-exchanged C{sub 60} ions and charged or neutral fragments (fullerene-like C{sub 60-2m} and small C{sub n} particles), and their fractions decrease with decreasing the projectile velocity. It is concluded that the C{sub 60} transmission fraction is considerably high for both types of the capillaries in the present velocity range.

  13. Safety barriers and lighting columns.

    NARCIS (Netherlands)

    Schreuder, D.A.

    1972-01-01

    Problems arising from the sitting of lighting columns on the central reserve are reviewed, and remedial measures such as break-away lighting supports and installation of safety fences on the central reserve on both sides of the lighting columns are examined.

  14. A capillary viscometer designed for the characterization of biocompatible ferrofluids

    Energy Technology Data Exchange (ETDEWEB)

    Nowak, J., E-mail: johannes.nowak@tu-dresden.de; Odenbach, S.

    2016-08-01

    Suspensions of magnetic nanoparticles are receiving a growing interest in biomedical research. These ferrofluids can, e.g., be used for the treatment of cancer, making use of the drug targeting principle or using an artificially induced heating. To enable a safe application the basic properties of the ferrofluids have to be well understood, including the viscosity of the fluids if an external magnetic field is applied. It is well known that the viscosity of ferrofluids rises if a magnetic field is applied, where the rise depends on shear rate and magnetic field strength. In case of biocompatible ferrofluids such investigations proved to be rather complicated as the experimental setup should be close to the actual application to allow justified predictions of the effects which have to be expected. Thus a capillary viscometer, providing a flow situation comparable to the flow in a blood vessel, has been designed. The glass capillary is exchangeable and different inner diameters can be used. The range of the shear rates has been adapted to the range found in the human organism. The application of an external magnetic field is enabled with two different coil setups covering the ranges of magnetic field strengths required on the one hand for a theoretical understanding of particle interaction and resulting changes in viscosity and on the other hand for values necessary for a potential biomedical application. The results show that the newly designed capillary viscometer is suitable to measure the magnetoviscous effect in biocompatible ferrofluids and that the results appear to be consistent with data measured with rotational rheometry. In addition, a strong change of the flow behaviour of a biocompatible ferrofluid was proven for ranges of the shear rate and the magnetic field strength expected for a potential biomedical application. - Highlights: • A capillary viscometer to characterize biocompatible ferrofluids is presented. • Shear rates and capillary diameters

  15. Vacuum scanning capillary photoemission microscopy

    DEFF Research Database (Denmark)

    Aseyev, S.A.; Cherkun, A P; Mironov, B N

    2017-01-01

    of a gold reflecting layer on a compact disc which has been illuminated by an unfocused laser beam with a wavelength 400nm, from a femtosecond laser with a beam size of 4mm. A quartz capillary with a 2-µm aperture has been used in the experiments. The period of gold microstructure, shown to be 1.6µ...... distribution of the recorded photoelectrons consisted of periodic mountain-valley strips, resembling the surface profile of the sample. Submicron spatial resolution has been achieved. This approach paves the way to study pulsed photodesorption of large organic molecular ions with high spatial and element...

  16. High-Efficiency On-Line Solid-Phase Extraction Coupling to 15-150 um I.D. Column Liquid Chromatography for Proteomic Analysis

    International Nuclear Information System (INIS)

    Shen, Yufeng; Moore, Ronald J.; Zhao, Rui; Blonder, Josip; Auberry, Deanna L.; Masselon, Christophe D.; Pasa Tolic, Ljiljana; Hixson, Kim K.; Auberry, Kenneth J.; Smith, Richard D.

    2003-01-01

    Flexible manipulation of various properties of proteomic samples is important for proteomic analyses, but it has been little explored for newly developed approaches based on liquid chromatography (LC) in combination with mass spectrometry (MS). With miniaturization of the LC column inner diameter dimensions (required for improving the analysis sensitivity), this issue becomes more challenging due to the small flow rates and the increasing effects of extra column volume on the separation quality and its use for resolving complex proteomic mixtures. In this study, we used commercial switching valves (150-mm channels) to implement the on-line coupling of capillary LC columns with relatively large solid phase extraction (SPE) columns operated at 10,000 psi. With optimized column connections, switching modes, and SPE column dimensions, high-efficiency on-line SPE-capillary and nanoscale LC separations were obtained with peak capacities of ∼1000 for capillaries having inner diameters between 15 to 150 mm. The on-line coupled SPE columns increased the sample processing capabilities by ∼400-fold for sample solution volume and ∼10-fold for sample mass. The proteomic applications of this on-line SPE-capillary LC system were evaluated for analysis of both soluble and membrane protein tryptic digests. Used with an ion trap tandem MS we could typically identify 1100-1500 peptides for analyses in a single 5-hour run. Peptides extracted on the SPE column and eluted from the LC column covered a hydrophilicity/hydrophobicity range that include an estimated ∼98% of all the tryptic peptides. The present implementation also facilitates automation and enables use of both disposable SPE columns and electrospray emitters, providing a robust basis for routine proteomic analyses.

  17. Slow physics: recording the ascent and descent of a water column

    Science.gov (United States)

    Lindén, Johan; Källman, Kjell-Mikael; Holm, Erik

    2018-07-01

    A glass filled with carbon dioxide gas upside down on a plate of water constitutes an excellent demonstration of the solubility of gases. If the water level on the plate is maintained the CO2 will slowly dissolve and the column of water will rise inside the glass, without quite reaching the ceiling, before an opposite process sets in: the water level will even more slowly begin to sink in a process which will take several years. We followed the process for several months, recording images of the water column with 10 min to 1 h intervals. The physics of the process is discussed and modeled quantitatively.

  18. Mush Column Magma Chambers

    Science.gov (United States)

    Marsh, B. D.

    2002-12-01

    Magma chambers are a necessary concept in understanding the chemical and physical evolution of magma. The concept may well be similar to a transfer function in circuit or time series analysis. It does what needs to be done to transform source magma into eruptible magma. In gravity and geodetic interpretations the causative body is (usually of necessity) geometrically simple and of limited vertical extent; it is clearly difficult to `see' through the uppermost manifestation of the concentrated magma. The presence of plutons in the upper crust has reinforced the view that magma chambers are large pots of magma, but as in the physical representation of a transfer function, actual magma chambers are clearly distinct from virtual magma chambers. Two key features to understanding magmatic systems are that they are vertically integrated over large distances (e.g., 30-100 km), and that all local magmatic processes are controlled by solidification fronts. Heat transfer considerations show that any viable volcanic system must be supported by a vertically extensive plumbing system. Field and geophysical studies point to a common theme of an interconnected stack of sill-like structures extending to great depth. This is a magmatic Mush Column. The large-scale (10s of km) structure resembles the vertical structure inferred at large volcanic centers like Hawaii (e.g., Ryan et al.), and the fine scale (10s to 100s of m) structure is exemplified by ophiolites and deeply eroded sill complexes like the Ferrar dolerites of the McMurdo Dry Valleys, Antarctica. The local length scales of the sill reservoirs and interconnecting conduits produce a rich spectrum of crystallization environments with distinct solidification time scales. Extensive horizontal and vertical mushy walls provide conditions conducive to specific processes of differentiation from solidification front instability to sidewall porous flow and wall rock slumping. The size, strength, and time series of eruptive behavior

  19. Ion guiding and losses in insulator capillaries

    International Nuclear Information System (INIS)

    Juhasz, Z.; Sulik, B.; Vikor, Gy.; Biri, S.; Fekete, E.; Ivan, I.; Gall, F.; Toekesi, K.; Matefi-Tempfli, S.; Matefi-Tempfli, M.

    2007-01-01

    Complete text of publication follows. Not long ago it was discovered that insulating capillaries can guide slow ions, so that the ions avoid close contact with the capillary walls and preserve their initial charge state. This phenomenon did not only give a new puzzle for theoreticians but opened the way for new possible applications where ions are manipulated (deflected, focused and directed to different patterns on the irradiated media) with small capillary devices. The most important question for such applications is how large fraction of the ions can be guided to the desired direction. It is already known that the ion guiding is due to the charging up of the inner capillary walls by earlier ion impact events. In tilted capillaries one side of the capillary walls charges up. This deflects the later arriving ions, so that some of them pass through the capillaries nearly parallel with respect to their axes. The angle where the transmission drops to 1/e of the direct transmission at 0 deg is the guiding angle, which characterize the guiding ability. At 0 deg the ideal 100 percent transmission for the ions, which enter the capillaries, is reduced due to the mirror charge attraction and geometrical imperfections. These losses appear in the transmission for tilted capillaries with similar magnitude, since after the deflection region, which usually restricted to the close surroundings of the capillary openings, the guided ions pass through the rest of the capillaries as in non-tilted samples. In our experimental studies with Al 2 O 3 capillaries we found that around 90 percent of the incoming ions are lost. To understand these significant losses, the effects of the mirror charge attraction and geometrical imperfections have been calculated classically. The mirror charge potential was taken from.The model of the capillaries used in the calculations can be seen in Figure 1. The calculations have shown that the effects of mirror charge attraction and the angular

  20. Two-dimensional capillary origami

    Energy Technology Data Exchange (ETDEWEB)

    Brubaker, N.D., E-mail: nbrubaker@math.arizona.edu; Lega, J., E-mail: lega@math.arizona.edu

    2016-01-08

    We describe a global approach to the problem of capillary origami that captures all unfolded equilibrium configurations in the two-dimensional setting where the drop is not required to fully wet the flexible plate. We provide bifurcation diagrams showing the level of encapsulation of each equilibrium configuration as a function of the volume of liquid that it contains, as well as plots representing the energy of each equilibrium branch. These diagrams indicate at what volume level the liquid drop ceases to be attached to the endpoints of the plate, which depends on the value of the contact angle. As in the case of pinned contact points, three different parameter regimes are identified, one of which predicts instantaneous encapsulation for small initial volumes of liquid. - Highlights: • Full solution set of the two-dimensional capillary origami problem. • Fluid does not necessarily wet the entire plate. • Global energy approach provides exact differential equations satisfied by minimizers. • Bifurcation diagrams highlight three different regimes. • Conditions for spontaneous encapsulation are identified.

  1. Two-dimensional capillary origami

    International Nuclear Information System (INIS)

    Brubaker, N.D.; Lega, J.

    2016-01-01

    We describe a global approach to the problem of capillary origami that captures all unfolded equilibrium configurations in the two-dimensional setting where the drop is not required to fully wet the flexible plate. We provide bifurcation diagrams showing the level of encapsulation of each equilibrium configuration as a function of the volume of liquid that it contains, as well as plots representing the energy of each equilibrium branch. These diagrams indicate at what volume level the liquid drop ceases to be attached to the endpoints of the plate, which depends on the value of the contact angle. As in the case of pinned contact points, three different parameter regimes are identified, one of which predicts instantaneous encapsulation for small initial volumes of liquid. - Highlights: • Full solution set of the two-dimensional capillary origami problem. • Fluid does not necessarily wet the entire plate. • Global energy approach provides exact differential equations satisfied by minimizers. • Bifurcation diagrams highlight three different regimes. • Conditions for spontaneous encapsulation are identified.

  2. Mixed Fluid Conditions: Capillary Phenomena

    KAUST Repository

    Santamarina, Carlos

    2017-07-06

    Mixed fluid phenomena in porous media have profound implications on soil-atmosphere interaction, energy geotechnology, environmental engineering and infrastructure design. Surface tension varies with pressure, temperature, solute concentration, and surfactant concentration; on the other hand, the contact angle responds to interfacial tensions, surface topography, invasion velocity, and chemical interactions. Interfaces are not isolated but interact through the fluid pressure and respond to external fields. Jumps, snap-offs and percolating wetting liquids along edges and crevices are ubiquitous in real, non-cylindrical porous networks. Pore- and macroscale instabilities together with pore structure variability-and-correlation favor fluid trapping and hinder recovery efficiency. The saturation-pressure characteristic curve is affected by the saturation-history, flow-rate, the mechanical response of the porous medium, and time-dependent reactive and diffusive processes; in addition, there are salient differences between unsaturation by internal gas nucleation and gas invasion. Capillary forces add to other skeletal forces in the porous medium and can generate open-mode discontinuities when the capillary entry pressure is high relative to the effective stress. Time emerges as an important variable in mixed-fluid conditions and common quasi-static analyses may fail to capture the system response.

  3. Equilibrium capillary forces with atomic force microscopy

    NARCIS (Netherlands)

    Sprakel, J.H.B.; Besseling, N.A.M.; Leermakers, F.A.M.; Cohen Stuart, M.A.

    2007-01-01

    We present measurements of equilibrium forces resulting from capillary condensation. The results give access to the ultralow interfacial tensions between the capillary bridge and the coexisting bulk phase. We demonstrate this with solutions of associative polymers and an aqueous mixture of gelatin

  4. Sheathless interface for coupling capillary electrophoresis with mass spectrometry

    Science.gov (United States)

    Wang, Chenchen; Tang, Keqi; Smith, Richard D.

    2014-06-17

    A sheathless interface for coupling capillary electrophoresis (CE) with mass spectrometry is disclosed. The sheathless interface includes a separation capillary for performing CE separation and an emitter capillary for electrospray ionization. A portion of the emitter capillary is porous or, alternatively, is coated to form an electrically conductive surface. A section of the emitter capillary is disposed within the separation capillary, forming a joint. A metal tube, containing a conductive liquid, encloses the joint.

  5. Column-Oriented Database Systems (Tutorial)

    NARCIS (Netherlands)

    D. Abadi; P.A. Boncz (Peter); S. Harizopoulos

    2009-01-01

    textabstractColumn-oriented database systems (column-stores) have attracted a lot of attention in the past few years. Column-stores, in a nutshell, store each database table column separately, with attribute values belonging to the same column stored contiguously, compressed, and densely packed, as

  6. Dynamic Deformation and Collapse of Granular Columns

    Science.gov (United States)

    Uenishi, K.; Tsuji, K.; Doi, S.

    2009-12-01

    Large dynamic deformation of granular materials may be found in nature not only in the failure of slopes and cliffs — due to earthquakes, rock avalanches, debris flows and landslides — but also in earthquake faulting itself. Granular surface flows often consist of solid grains and intergranular fluid, but the effect of the fluid may be usually negligible because the volumetric concentration of grains is in many cases high enough for interparticle forces to dominate momentum transport. Therefore, the investigation of dry granular flow of a mass might assist in further understanding of the above mentioned geophysical events. Here, utilizing a high-speed digital video camera system, we perform a simple yet fully-controlled series of laboratory experiments related to the collapse of granular columns. We record, at an interval of some microseconds, the dynamic transient granular mass flow initiated by abrupt release of a tube that contains dry granular materials. The acrylic tube is partially filled with glass beads and has a cross-section of either a fully- or semi-cylindrical shape. Upon sudden removal of the tube, the granular solid may fragment under the action of its own weight and the particles spread on a rigid horizontal plane. This study is essentially the extension of the previous ones by Lajeunesse et al. (Phys. Fluids 2004) and Uenishi and Tsuji (JPGU 2008), but the striped layers of particles in a semi-cylindrical tube, newly introduced in this contribution, allow us to observe the precise particle movement inside the granular column: The development of slip lines inside the column and the movement of particles against each other can be clearly identified. The major controlling parameters of the spreading dynamics are the initial aspect ratio of the granular (semi-)cylindrical column, the frictional properties of the horizontal plane (substrate) and the size of beads. We show the influence of each parameter on the average flow velocity and final radius

  7. The penetration of aerosols through fine capillaries

    International Nuclear Information System (INIS)

    Mitchell, J.P.; Edwards, R.T.; Ball, M.H.E.

    1989-10-01

    A novel experimental technique has been developed to study the penetration of aerosol particles ranging from about 1 to 15 μm aerodynamic diameter through capillaries varying from 20 to 80 μm bore and from 10 to 50 mm in length. When the driving pressure was 100 kPa, the penetration of the airborne particles was considerably smaller than expected from a simple comparison of particle diameter with the bore of the capillary. Particle size distributions determined after penetration through the capillaries were in almost all cases similar to the particle size distribution of the aerosol at the capillary entrance. This lack of size-selectivity can be explained in terms of the capillary behaving as a conventional suction-based sampler from a near still (calm) air environment. The resulting particle penetration data are important in assessing the potential for the leakage of aerosols through seals in containers used to transport radioactive materials. (author)

  8. CRYSTALLIZATION IN MULTICOMPONENT GLASSES

    Energy Technology Data Exchange (ETDEWEB)

    KRUGER AA; HRMA PR

    2009-10-08

    In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures involving partial crystallization. In the glass melter, crystals form and dissolve during batch-to-glass conversion, melter processing, and product cooling. Crystals often agglomerate and sink, and they may settle at the melter bottom. Within the body of cooling glass, multiple phases crystallize in a non-uniform time-dependent temperature field. Self-organizing periodic distribution (the Liesegnang effect) is common. Various crystallization phenomena that occur in glass making are reviewed.

  9. Crystallization In Multicomponent Glasses

    International Nuclear Information System (INIS)

    Kruger, A.A.; Hrma, P.R.

    2009-01-01

    In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures involving partial crystallization. In the glass melter, crystals form and dissolve during batch-to-glass conversion, melter processing, and product cooling. Crystals often agglomerate and sink, and they may settle at the melter bottom. Within the body of cooling glass, multiple phases crystallize in a non-uniform time-dependent temperature field. Self-organizing periodic distribution (the Liesegnang effect) is common. Various crystallization phenomena that occur in glass making are reviewed.

  10. Glass Masonry - Experimental Verification of Bed Joint under Shear

    Science.gov (United States)

    Fíla, J.; Eliášová, M.; Sokol, Z.

    2017-10-01

    Glass is considered as a traditional material for building industry but was mostly used for glazing of the windows. At present, glass is an integral part of contemporary architecture where glass structural elements such as beams, stairs, railing ribs or columns became popular in the last two decades. However, using glass as structural material started at the beginning of 20th century, when masonry from hollow glass blocks were used. Using solid glass brick is very rare and only a few structures with solid glass bricks walls have been built in the last years. Pillars and walls made from solid glass bricks are mainly loaded by compression and/or bending from the eccentricity of vertical load or wind load. Due to high compressive strength of glass, the limiting factor of the glass masonry is the joint between the glass bricks as the smooth surface requires another type of mortar / glue compared to traditional masonry. Shear resistance and failure modes of brick bed joint was determined during series of tests using various mortars, two types of surface treatment and different thickness of the mortar joint. Shear tests were completed by small scale tests for mortar - determination of flexural and compressive strength of hardened mortar.

  11. Genetics Home Reference: megalencephaly-capillary malformation syndrome

    Science.gov (United States)

    ... Additional NIH Resources (1 link) National Institute of Neurological Disorders and Stroke: Megalencephaly Educational Resources (5 links) Boston Children's Hospital: Capillary Malformation Cincinnati Children's Hospital: Capillary Malformations ...

  12. Application of Homochiral Alkylated Organic Cages as Chiral Stationary Phases for Molecular Separations by Capillary Gas Chromatography.

    Science.gov (United States)

    Xie, Shengming; Zhang, Junhui; Fu, Nan; Wang, Bangjin; Hu, Cong; Yuan, Liming

    2016-11-08

    Molecular organic cage compounds have attracted considerable attention due to their potential applications in gas storage, catalysis, chemical sensing, molecular separations, etc. In this study, a homochiral pentyl cage compound was synthesized from a condensation reaction of ( S , S )-1,2-pentyl-1,2-diaminoethane and 1,3,5-triformylbenzene. The imine-linked pentyl cage diluted with a polysiloxane (OV-1701) was explored as a novel stationary phase for high-resolution gas chromatographic separation of organic compounds. Some positional isomers were baseline separated on the pentyl cage-coated capillary column. In particular, various types of enantiomers including chiral alcohols, esters, ethers and epoxides can be resolved without derivatization on the pentyl cage-coated capillary column. The reproducibility of the pentyl cage-coated capillary column for separation was investigated using nitrochlorobenzene and styrene oxide as analytes. The results indicate that the column has good stability and separation reproducibility after being repeatedly used. This work demonstrates that molecular organic cage compounds could become a novel class of chiral separation media in the near future.

  13. Application of Homochiral Alkylated Organic Cages as Chiral Stationary Phases for Molecular Separations by Capillary Gas Chromatography

    Directory of Open Access Journals (Sweden)

    Shengming Xie

    2016-11-01

    Full Text Available Molecular organic cage compounds have attracted considerable attention due to their potential applications in gas storage, catalysis, chemical sensing, molecular separations, etc. In this study, a homochiral pentyl cage compound was synthesized from a condensation reaction of (S,S-1,2-pentyl-1,2-diaminoethane and 1,3,5-triformylbenzene. The imine-linked pentyl cage diluted with a polysiloxane (OV-1701 was explored as a novel stationary phase for high-resolution gas chromatographic separation of organic compounds. Some positional isomers were baseline separated on the pentyl cage-coated capillary column. In particular, various types of enantiomers including chiral alcohols, esters, ethers and epoxides can be resolved without derivatization on the pentyl cage-coated capillary column. The reproducibility of the pentyl cage-coated capillary column for separation was investigated using nitrochlorobenzene and styrene oxide as analytes. The results indicate that the column has good stability and separation reproducibility after being repeatedly used. This work demonstrates that molecular organic cage compounds could become a novel class of chiral separation media in the near future.

  14. Capillary leak syndrome: etiologies, pathophysiology, and management.

    Science.gov (United States)

    Siddall, Eric; Khatri, Minesh; Radhakrishnan, Jai

    2017-07-01

    In various human diseases, an increase in capillary permeability to proteins leads to the loss of protein-rich fluid from the intravascular to the interstitial space. Although sepsis is the disease most commonly associated with this phenomenon, many other diseases can lead to a "sepsis-like" syndrome with manifestations of diffuse pitting edema, exudative serous cavity effusions, noncardiogenic pulmonary edema, hypotension, and, in some cases, hypovolemic shock with multiple-organ failure. The term capillary leak syndrome has been used to describe this constellation of disease manifestations associated with an increased capillary permeability to proteins. Diseases other than sepsis that can result in capillary leak syndrome include the idiopathic systemic capillary leak syndrome or Clarkson's disease, engraftment syndrome, differentiation syndrome, the ovarian hyperstimulation syndrome, hemophagocytic lymphohistiocytosis, viral hemorrhagic fevers, autoimmune diseases, snakebite envenomation, and ricin poisoning. Drugs including some interleukins, some monoclonal antibodies, and gemcitabine can also cause capillary leak syndrome. Acute kidney injury is commonly seen in all of these diseases. In addition to hypotension, cytokines are likely to be important in the pathophysiology of acute kidney injury in capillary leak syndrome. Fluid management is a critical part of the treatment of capillary leak syndrome; hypovolemia and hypotension can cause organ injury, whereas capillary leakage of administered fluid can worsen organ edema leading to progressive organ injury. The purpose of this article is to discuss the diseases other than sepsis that produce capillary leak and review their collective pathophysiology and treatment. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  15. Two-dimensional capillary electrophoresis: capillary isoelectric focusing and capillary zone electrophoresis with laser-induced fluorescence detection

    Science.gov (United States)

    Dickerson, Jane A.; Ramsay, Lauren M.; Dada, Oluwatosin O.; Cermak, Nathan

    2011-01-01

    Capillary isoelectric focusing and capillary zone electrophoresis are coupled with laser-induced fluorescence detection to create an ultrasensitive two-dimensional separation method for proteins. In this method, two capillaries are joined through a buffer filled interface. Separate power supplies control the potential at the injection end of the first capillary and at the interface; the detector is held at ground potential. Proteins are labeled with the fluorogenic reagent Chromeo P503, which preserves the isoelectric point of the labeled protein. The labeled proteins were mixed with ampholytes and injected into the first dimension capillary. A focusing step was performed with the injection end of the capillary at high pH and the interface at low pH. To mobilize components, the interface was filled with a high pH buffer, which was compatible with the second dimension separation. A fraction was transferred to the second dimension capillary for separation. The process of fraction transfer and second dimension separation was repeated two dozen times. The separation produced a spot capacity of 125. PMID:20603830

  16. Water Column Sonar Data Collection

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The collection and analysis of water column sonar data is a relatively new avenue of research into the marine environment. Primary uses include assessing biological...

  17. Recycling of Glass

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Damgaard, Anders

    2011-01-01

    Glass is used for many purposes, but in the waste system glass is predominantly found in terms of beverage and food containers with a relatively short lifetime before ending up in the waste. Furthermore there is a large amount of flat glass used in building materials which also ends up in the waste...... system; this glass though has a long lifetime before ending up in the waste. Altogether these product types add up to 82% of the production of the European glass industry (IPCC, 2001). Recycling of glass in terms of cleaning and refilling of bottles as well as the use of broken glass in the production...... of new glass containers is well established in the glass industry. This chapter describes briefly howglass is produced and howwaste glass is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of glass recycling....

  18. LIQUID-LIQUID EXTRACTION COLUMNS

    Science.gov (United States)

    Thornton, J.D.

    1957-12-31

    This patent relates to liquid-liquid extraction columns having a means for pulsing the liquid in the column to give it an oscillatory up and down movement, and consists of a packed column, an inlet pipe for the dispersed liquid phase and an outlet pipe for the continuous liquid phase located in the direct communication with the liquid in the lower part of said column, an inlet pipe for the continuous liquid phase and an outlet pipe for the dispersed liquid phase located in direct communication with the liquid in the upper part of said column, a tube having one end communicating with liquid in the lower part of said column and having its upper end located above the level of said outlet pipe for the dispersed phase, and a piston and cylinder connected to the upper end of said tube for applying a pulsating pneumatic pressure to the surface of the liquid in said tube so that said surface rises and falls in said tube.

  19. Column-Oriented Database Systems (Tutorial)

    OpenAIRE

    Abadi, D.; Boncz, Peter; Harizopoulos, S.

    2009-01-01

    textabstractColumn-oriented database systems (column-stores) have attracted a lot of attention in the past few years. Column-stores, in a nutshell, store each database table column separately, with attribute values belonging to the same column stored contiguously, compressed, and densely packed, as opposed to traditional database systems that store entire records (rows) one after the other. Reading a subset of a table’s columns becomes faster, at the potential expense of excessive disk-head s...

  20. Design and Operation of Cryogenic Distillation Research Column for Ultra-Low Background Experiments

    Science.gov (United States)

    Chiller, Christopher; Alanson Chiller, Angela; Jasinski, Benjamin; Snyder, Nathan; Mei, Dongming

    2013-04-01

    Motivated by isotopically enriched germanium (76Ge and 73Ge) for monocrystalline crystal growth for neutrinoless double-beta decay and dark matter experiments, a cryogenic distillation research column was developed. Without market availability of distillation columns in the temperature range of interest with capabilities necessary for our purposes, we designed, fabricated, tested, refined and operated a two-meter research column for purifying and separating gases in the temperature range from 100-200K. Due to interest in defining stratification, purity and throughput optimization, capillary lines were integrated at four equidistant points along the length of the column such that real-time residual gas analysis could guide the investigation. Interior gas column temperatures were monitored and controlled within 0.1oK accuracy at the top and bottom. Pressures were monitored at the top of the column to four significant figures. Subsequent impurities were measured at partial pressures below 2E-8torr. We report the performance of the column in this paper.

  1. Relating pressure tuned coupled column ensembles with the solvation parameter model for tunable selectivity in gas chromatography.

    Science.gov (United States)

    Sharif, Khan M; Kulsing, Chadin; Chin, Sung-Tong; Marriott, Philip J

    2016-07-15

    The differential pressure drop of carrier gas by tuning the junction point pressure of a coupled column gas chromatographic system leads to a unique selectivity of the overall separation, which can be tested using a mixture of compounds with a wide range of polarity. This study demonstrates a pressure tuning (PT) GC system employing a microfluidic Deans switch located at the mid-point of the two capillary columns. This PT system allowed variations of inlet-outlet pressure differences of the two columns in a range of 52-17psi for the upstream column and 31-11psi for the downstream column. Peak shifting (differential migration) of compounds due to PT difference are related to a first order regression equation in a Plackett-Burman factorial study. Increased first (upstream) column pressure drop makes the second column characteristics more significant in the coupled column retention behavior, and conversely increased second (downstream) column pressure drop makes the first column characteristics more apparent; such variation can result in component swapping between polar and non-polar compounds. The coupled column system selectivity was evaluated in terms of linear solvation energy relationship (LSER) parameters, and their relation with different pressure drop effects has been constructed by applying multivariate principle component analysis (PCA). It has been found that the coupled column PT system descriptors provide a result that shows a clear clustering of different pressure settings, somewhat intermediate between those of the two commercial columns. This is equivalent to that obtained from a conventional single-column GC analysis where the interaction energy contributed from the stationary phases can be significantly adjusted by choice of midpoint PT. This result provides a foundation for pressure differentiation for selectivity enhancement. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Interior Temperature Measurement Using Curved Mercury Capillary Sensor Based on X-ray Radiography

    Science.gov (United States)

    Chen, Shuyue; Jiang, Xing; Lu, Guirong

    2017-07-01

    A method was presented for measuring the interior temperature of objects using a curved mercury capillary sensor based on X-ray radiography. The sensor is composed of a mercury bubble, a capillary and a fixed support. X-ray digital radiography was employed to capture image of the mercury column in the capillary, and a temperature control system was designed for the sensor calibration. We adopted livewire algorithms and mathematical morphology to calculate the mercury length. A measurement model relating mercury length to temperature was established, and the measurement uncertainty associated with the mercury column length and the linear model fitted by least-square method were analyzed. To verify the system, the interior temperature measurement of an autoclave, which is totally closed, was taken from 29.53°C to 67.34°C. The experiment results show that the response of the system is approximately linear with an uncertainty of maximum 0.79°C. This technique provides a new approach to measure interior temperature of objects.

  3. Tritium isotope separation by water distillation column packed with silica-gel beads

    International Nuclear Information System (INIS)

    Fukada, Satoshi

    2004-01-01

    Tritium enrichment or depletion by water distillation was investigated using a glass column of 32cm in height packed with silica-gel beads of 3.4mm in average diameter. The total separation factor of the silica-gel distillation column, α H-T , was compared with those of an open column distillation tower and of a column packed with stainless-steel Dixon rings. Depletion of the tritium activity in the distillate was enhanced by isotopic exchange with water absorbed on silica-gel beads that have a higher affinity for HTO than for H 2 O. The value of α H-T -1 of the silica-gel distillation column was about four times larger than that of a column without any packing and about two times larger than that of the Dixon-ring column. The improvement of α H-T by the silica-gel adsorbent indicated that the height of the distillation-adsorption column becomes shorter than that of the height of conventional distillation columns. (author)

  4. Nanoscale mechanochemical wear of phosphate laser glass against a CeO{sub 2} particle in humid air

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Jiaxin, E-mail: yujiaxin@swust.edu.cn [Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010 (China); He, Hongtu; Zhang, Yafeng [Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010 (China); Hu, Hailong [Analysis and Testing Center, Southwest University of Science and Technology, Mianyang 621010 (China)

    2017-01-15

    Highlights: • Friction components of phosphate glass/CeO{sub 2} pair in humid air were quantified to understand the friction mechanism. • Severe nanoscale wear was directly observed by AFM topography on both phosphate glass and CeO{sub 2} particle in humid air. • The wearless behaviors of phosphate glass in vacuum were confirmed by the AFM phase image. • Capillary water bridge induced corrosion plays an important role in the mechanochemical wear of phosphate glass in air. - Abstract: Using an atomic force microscope, the friction and wear of phosphate laser glass against a CeO{sub 2} particle were quantitatively studied both in humid air and in vacuum, to reveal the water molecules induced mechanochemical wear mechanism of phosphate laser glass. The friction coefficient of the glass/CeO{sub 2} pair in air was found to be 5–7 times higher than that in vacuum due to the formation of a capillary water bridge at the friction interface, with a contribution of the capillary-related friction to the total friction coefficient as high as 65–79%. The capillary water bridge further induced a serious material removal of glass and CeO{sub 2} particle surfaces, while supplying both a local liquid water environment to corrode the glass surface and a high shearing force to assist the stretching of the Ce−O−P bond, accelerating the reaction between water and the glass/CeO{sub 2} pair. In vacuum, however, no discernable wear phenomena were observed, but the phase images captured by AFM tapping mode suggested the occurrence of potential strain hardening in the friction area of the glass surface.

  5. Capillary condensation between disks in two dimensions

    DEFF Research Database (Denmark)

    Gil, Tamir; Ipsen, John Hjorth

    1997-01-01

    Capillary condensation between two two-dimensional wetted circular substrates (disks) is studied by an effective free energy description of the wetting interface. The interfacial free-energy potential is developed on the basis of the theory for the wetting of a single disk, where interfacial...... capillary fluctuations play a dominant role. A simple approximative analytical expression of the interfacial free energy is developed and is validated numerically. The capillary condensation is characterized by the analysis of the coverage of the condensed phase, its stability, and asymptotic behaviors...

  6. Spin glasses

    International Nuclear Information System (INIS)

    Mookerjee, Abhijit

    1976-01-01

    ''Spin glasses'', are entire class of magnetic alloys of moderate dilution, in which the magnetic atoms are far enough apart to be unlike the pure metal, but close enough so that the indirect exchange energy between them (mediated by the s-d interaction between local moments and conduction electrons) dominates all other energies. Characteristic critical phenomena displayed such as freezing of spin orientation at 'Tsub(c)' and spreading of magnetic ordering, are pointed out. Anomalous behaviour, associated with these critical phenomena, as reflected in : (i) Moessbauer spectroscopy giving hyperfine splitting at Tsub(c), (ii) maxima in susceptibility and remanent magnetism, (iii) thermopower maxima and change in slope, (iv) Characteristic cusp in susceptibility and its removal by very small magnetic fields, and (v) conductivity-resistivity measurements, are discussed. Theoretical developments aimed at explaining these phenomena, in particular, the ideas from percolation and localisation theories, and the approach based on the gellations of polymers, are discussed. Finally, a new approach based on renormalisation group in disordered systems is also briefly mentioned. (K.B.)

  7. Radiotracer Imaging of Sediment Columns

    Science.gov (United States)

    Moses, W. W.; O'Neil, J. P.; Boutchko, R.; Nico, P. S.; Druhan, J. L.; Vandehey, N. T.

    2010-12-01

    Nuclear medical PET and SPECT cameras routinely image radioactivity concentration of gamma ray emitting isotopes (PET - 511 keV; SPECT - 75-300 keV). We have used nuclear medical imaging technology to study contaminant transport in sediment columns. Specifically, we use Tc-99m (T1/2 = 6 h, Eγ = 140 keV) and a SPECT camera to image the bacteria mediated reduction of pertechnetate, [Tc(VII)O4]- + Fe(II) → Tc(IV)O2 + Fe(III). A 45 mL bolus of Tc-99m (32 mCi) labeled sodium pertechnetate was infused into a column (35cm x 10cm Ø) containing uranium-contaminated subsurface sediment from the Rifle, CO site. A flow rate of 1.25 ml/min of artificial groundwater was maintained in the column. Using a GE Millennium VG camera, we imaged the column for 12 hours, acquiring 44 frames. As the microbes in the sediment were inactive, we expected most of the iron to be Fe(III). The images were consistent with this hypothesis, and the Tc-99m pertechnetate acted like a conservative tracer. Virtually no binding of the Tc-99m was observed, and while the bolus of activity propagated fairly uniformly through the column, some inhomogeneity attributed to sediment packing was observed. We expect that after augmentation by acetate, the bacteria will metabolically reduce Fe(III) to Fe(II), leading to significant Tc-99m binding. Imaging sediment columns using nuclear medicine techniques has many attractive features. Trace quantities of the radiolabeled compounds are used (micro- to nano- molar) and the half-lives of many of these tracers are short (Image of Tc-99m distribution in a column containing Rifle sediment at four times.

  8. Performance evaluation of a rectifier column using gamma column scanning

    Directory of Open Access Journals (Sweden)

    Aquino Denis D.

    2017-12-01

    Full Text Available Rectifier columns are considered to be a critical component in petroleum refineries and petrochemical processing installations as they are able to affect the overall performance of these facilities. It is deemed necessary to monitor the operational conditions of such vessels to optimize processes and prevent anomalies which could pose undesired consequences on product quality that might lead to huge financial losses. A rectifier column was subjected to gamma scanning using a 10-mCi Co-60 source and a 2-inch-long detector in tandem. Several scans were performed to gather information on the operating conditions of the column under different sets of operating parameters. The scan profiles revealed unexpected decreases in the radiation intensity at vapour levels between trays 2 and 3, and between trays 4 and 5. Flooding also occurred during several scans which could be attributed to parametric settings.

  9. Characterization of oligosaccharides with capillary high performance anion exchange chromatography hyphenated to pulsed amperometric detection and ion trap mass spectrometry : application to the analysis of human lysosomal disorders

    NARCIS (Netherlands)

    Bruggink, Cornelis

    The development of a capillary ion chromatograph is described together with a matching desalter. This desalter made it possible to use on-line a mass spectrometer. The mass spectrometer enables partly to characterize carbohydrates eluting from the anion exchange column. This separation technology is

  10. Reduction of the capillary water absorption of foamed concrete by using the porous aggregate

    Science.gov (United States)

    Namsone, E.; Sahmenko, G.; Namsone, E.; Korjakins, A.

    2017-10-01

    The article reports on the research of reduction of the capillary water absorption of foamed concrete (FC) by using the porous aggregate such as the granules of expanded glass (EG) and the cenospheres (CS). The EG granular aggregate is produced by using recycled glass and blowing agents, melted down in high temperature. The unique structure of the EG granules is obtained where the air is kept closed inside the pellet. The use of the porous aggregate in the preparation process of the FC samples provides an opportunity to improve some physical and mechanical properties of the FC, classifying it as a product of high-performance. In this research the FC samples were produced by adding the EG granules and the CS. The capillary water absorption of hardened samples has been verified. The pore size distribution has been determined by microscope. It is a very important characteristic, specifically in the cold climate territories-where temperature often falls below zero degrees. It is necessary to prevent forming of the micro sized pores in the final structure of the material as it reduces its water absorption capacity. In addition, at a below zero temperature water inside these micro sized pores can increase them by expanding the stress on their walls during the freezing process. Research of the capillary water absorption kinetics can be practical for prevision of the FC durability.

  11. Post column derivatisation analyses review. Is post-column derivatisation incompatible with modern HPLC columns?

    Science.gov (United States)

    Jones, Andrew; Pravadali-Cekic, Sercan; Dennis, Gary R; Shalliker, R Andrew

    2015-08-19

    Post Column derivatisation (PCD) coupled with high performance liquid chromatography or ultra-high performance liquid chromatography is a powerful tool in the modern analytical laboratory, or at least it should be. One drawback with PCD techniques is the extra post-column dead volume due to reaction coils used to enable adequate reaction time and the mixing of reagents which causes peak broadening, hence a loss of separation power. This loss of efficiency is counter-productive to modern HPLC technologies, -such as UHPLC. We reviewed 87 PCD methods published from 2009 to 2014. We restricted our review to methods published between 2009 and 2014, because we were interested in the uptake of PCD methods in UHPLC environments. Our review focused on a range of system parameters including: column dimensions, stationary phase and particle size, as well as the geometry of the reaction loop. The most commonly used column in the methods investigated was not in fact a modern UHPLC version with sub-2-micron, (or even sub-3-micron) particles, but rather, work-house columns, such as, 250 × 4.6 mm i.d. columns packed with 5 μm C18 particles. Reaction loops were varied, even within the same type of analysis, but the majority of methods employed loop systems with volumes greater than 500 μL. A second part of this review illustrated briefly the effect of dead volume on column performance. The experiment evaluated the change in resolution and separation efficiency of some weak to moderately retained solutes on a 250 × 4.6 mm i.d. column packed with 5 μm particles. The data showed that reaction loops beyond 100 μL resulted in a very serious loss of performance. Our study concluded that practitioners of PCD methods largely avoid the use of UHPLC-type column formats, so yes, very much, PCD is incompatible with the modern HPLC column. Copyright © 2015. Published by Elsevier B.V.

  12. Column Experiments to Interpret Weathering in Columbia Hills

    Science.gov (United States)

    Hausrath, E. M.; Morris, R.V.; Ming, D.W.; Golden, D.C.; Galindo, C.; Sutter, B.

    2009-01-01

    Phosphate mobility has been postulated as an indicator of early aqueous activity on Mars. In addition, rock surfaces analyzed by the Mars Exploration Rover Spirit are consistent with the loss of a phosphate- containing mineral To interpret phosphate alteration behavior on Mars, we performed column dissolution experiments leaching the primary phases Durango fluorapatite, San Carlos olivine, and basalt glass (Stapafjell Volcano, courtesy of S. Gislason, University of Iceland) [3,4]) with acidic solutions. These phases were chosen to represent quickly dissolving phases likely present in Columbia Hills. Column dissolution experiments are closer to natural dissolution conditions than batch experiments, although they can be difficult to interpret. Acidic solutions were used because the leached layers on the surfaces of these rocks have been interpreted as resulting from acid solutions [5].

  13. Design of an ion exchange column for plutonium recovery

    International Nuclear Information System (INIS)

    Araujo, J.A. de; Matsuda, H.T.; Santos Tome Lobao, A. dos; Quesada, A.C.

    1994-01-01

    An ion exchange column design for plutonium recovering from scraps of the MOX fuel elements fabrication is presented. The proposed column is constructed in 304 stainless steel and borosilicate glass provided of heating-jacket and temperature control and pressure relief devices. Safety aspects required for alpha emitters handling have been also considered. The design and construction were performed totally at Brazilian Institute for Energetic and Nuclear Research. The equipment will be used in the plutonium separation step as a part of an installation named Facilidad Alfa at the Centro Atomico de Constituyentes-CNEA/Buenos Aires, where other processes, including dissolution denitration by microwaves and final steps of MOX pellets re-fabrication will be performed. (author). 4 refs, 3 figs

  14. Nanoparticle-based capillary electroseparation of proteins in polymer capillaries under physiological conditions

    DEFF Research Database (Denmark)

    Nilsson, C.; Harwigsson, I.; Becker, K.

    2010-01-01

    Totally porous lipid-based liquid crystalline nanoparticles were used as pseudostationary phase for capillary electroseparation with LIF detection of proteins at physiological conditions using unmodified cyclic olefin copolymer capillaries (Topas (R), 6.7 cm effective length). In the absence of n...... at protein friendly conditions. The developed capillary-based method facilitates future electrochromatography of proteins on polymer-based microchips under physiological conditions and enables the initial optimization of separation conditions in parallel to the chip development....

  15. Preparation and evaluation of 400μm I.D. polymer-based hydrophilic interaction chromatography monolithic columns with high column efficiency.

    Science.gov (United States)

    Liu, Chusheng; Li, Haibin; Wang, Qiqin; Crommen, Jacques; Zhou, Haibo; Jiang, Zhengjin

    2017-08-04

    The quest for higher column efficiency is one of the major research areas in polymer-based monolithic column fabrication. In this research, two novel polymer-based HILIC monolithic columns with 400μm I.D.×800μm O.D. were prepared based on the thermally initiated co-polymerization of N,N-dimethyl-N-(3-methacrylamidopropyl)-N-(3-sulfopropyl) ammonium betaine (SPP) and ethylene glycol dimethacrylate (EDMA) or N,N'-methylenebisacrylamide (MBA). In order to obtain a satisfactory performance in terms of column permeability, mechanical stability, efficiency and selectivity, the polymerization parameters were systematically optimized. Column efficiencies as high as 142, 000 plates/m and 120, 000 plates/m were observed for the analysis of neutral compounds at 0.6mm/s on the poly(SPP-co-MBA) and poly(SPP-co-EDMA) monoliths, respectively. Furthermore, the Van Deemter plots for thiourea on the two monoliths were compared with that on a commercial silica based ZIC-HILIC column (3.5μm, 200Å, 150mm×300μm I.D.) using ACN/H 2 O (90/10, v/v) as the mobile phase at room temperature. It was noticeable that the Van Deemter curves for both monoliths, particularly the poly(SPP-co-MBA) monolith, are significantly flatter than that obtained for the ZIC-HILIC column, which indicates that in spite of their larger internal diameters, they yield better overall efficiency, with less peak dispersion, across a much wider range of usable linear velocities. A clearly better separation performance was also observed for nucleobases, nucleosides, nucleotides and small peptides on the poly(SPP-co-MBA) monolith compared to the ZIC-HILIC column. It is particularly worth mentioning that these 400μm I.D. polymer-based HILIC monolithic columns exhibit enhanced mechanical strength owing to the thicker capillary wall of the fused-silica capillaries. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. X-ray tests of microfocusing mono-capillary optic for protein crystallography

    CERN Document Server

    Bilderback, D H

    2001-01-01

    A single, borosilicate-glass capillary was drawn into a 30.5 cm long elliptical shape. The inside diameter was 0.40 mm at the large base end and 0.13 mm at the tip. With 12 keV X-rays from the CHESS D1 bending magnet, the single-bounce capillary produced a focus of better than 18 mu m in diameter (FHWM) at a 3 cm distance from the capillary tip. A flux gain of 110 in the focus position was observed along with a total flux in the spot of 4x10 sup 1 sup 0 X-rays/s (conditions: 5.3 GeV, 182 mA, 1.5% bandwidth multilayer, 12 keV X-rays). A measurement of the far field focus ring diameter yielded a divergence of 3.8 mrad, in good agreement with the 4 mrad design of the optic for protein crystallography. Using a small 25 mu m square beam, we measured the local reflectivity to be greater than 95% and the inner slope errors of the capillary to average about +-150 mu rad, both from raw and elliptically shaped tubing. Our conclusion is that more perfect starting tubing (i.e. one with lower slope errors) is needed to ma...

  17. Liquid distribution and cohesion in wet granular assemblies beyond the capillary bridge regime

    International Nuclear Information System (INIS)

    Scheel, M; Seemann, R; Brinkmann, M; Herminghaus, S; Di Michiel, M; Sheppard, A

    2008-01-01

    Dry sand turns into a stiff and moldable material as soon as it is mixed with some liquid. This is a direct consequence of the internal liquid-air interfaces spanning between the grains which causes capillary cohesion by virtue of the surface tension of the liquid. As a model for wet granulates we investigated random packings of submillimeter spherical beads mixed with water. Measurements of the tensile strength and the fluidization threshold demonstrate that the mechanical stiffness is rather insensitive to the liquid content over a wide range. Only for a high liquid content, when more than half of the available pore space is filled with liquid, does the capillary cohesion weaken. In order to understand the interplay between the mechanical properties and the liquid content, we investigated the liquid distribution in random packings of glass spheres by means of x-ray microtomography. The three-dimensional images reveal that the liquid forms a network of capillary bridges fused at local triangular bead configurations. The spontaneous organization of the liquid into these ramified structures, which exhibit a large liquid-air interface, is responsible for the constancy of the cohesive forces in a wide range of liquid contents beyond the onset of capillary bridge coalescence.

  18. Microgravity Investigation of Capillary Driven Imbibition

    Science.gov (United States)

    Dushin, V. R.; Nikitin, V. F.; Smirnov, N. N.; Skryleva, E. I.; Tyurenkova, V. V.

    2018-05-01

    The goal of the present paper is to investigate the capillary driven filtration in porous media under microgravity conditions. New mathematical model that allows taking into account the blurring of the front due to the instability of the displacement that is developing at the front is proposed. The constants in the mathematical model were selected on the basis of the experimental data on imbibition into unsaturated porous media under microgravity conditions. The flow under the action of a combination of capillary forces and a constant pressure drop or a constant flux is considered. The effect of capillary forces and the type of wettability of the medium on the displacement process is studied. A criterion in which case the capillary effects are insignificant and can be neglected is established.

  19. Characterization of asphaltenes by nonaqueous capillary electrophoresis

    NARCIS (Netherlands)

    Kok, W.T.; Tüdös, A.J.; Grutters, M.; Shepherd, A.G.

    2011-01-01

    Nonaqueous capillary electrophoresis was used for the separation and characterization of asphaltene samples from different sources. For the separation medium (background electrolyte), mixtures of tetrahydrofuran and a high-permittivity organic solvent could be used. The best results were obtained

  20. Hierarchical capillary adhesion of microcantilevers or hairs

    International Nuclear Information System (INIS)

    Liu Jianlin; Feng Xiqiao; Xia Re; Zhao Hongping

    2007-01-01

    As a result of capillary forces, animal hairs, carbon nanotubes or nanowires of a periodically or randomly distributed array often assemble into hierarchical structures. In this paper, the energy method is adopted to analyse the capillary adhesion of microsized hairs, which are modelled as clamped microcantilevers wetted by liquids. The critical conditions for capillary adhesion of two hairs, three hairs or two bundles of hairs are derived in terms of Young's contact angle, elastic modulus and geometric sizes of the beams. Then, the hierarchical capillary adhesion of hairs is addressed. It is found that for multiple hairs or microcantilevers, the system tends to take a hierarchical structure as a result of the minimization of the total potential energy of the system. The level number of structural hierarchy increases with the increase in the number of hairs if they are sufficiently long. Additionally, we performed experiments to verify our theoretical solutions for the adhesion of microbeams

  1. Fabrication of Two Columns Dye-Sensitized Solar-Cell

    International Nuclear Information System (INIS)

    Phyu Sin Khaing Oo; Su Su Hlaing; Khin Lay Thwe; Nwe Ni Khin

    2011-12-01

    A two columns dye-sensitized solar cell has been fabricated using dye extract form teak leaves. This solar cell was assembled with two 20-30 ohms conductive glasses (one for TiO2 coated electrode and another for carbon coated electrode), TiO2 nano-powder P25, iodide electrolyte solution and soft graphite pencil for carbon coating. It was found that the open circuit voltage Voc was 0.688V and the short circuit Isc was 0.724mA

  2. NOx retention in scrubbing column

    International Nuclear Information System (INIS)

    Nakazone, A.K.; Costa, R.E.; Lobao, A.S.T.; Matsuda, H.T.; Araujo, B.F.

    1988-07-01

    During the UO 2 dissolution in nitric acid, some different species of NO x are released. The off gas can either be refluxed to the dissolver or be released and retained on special columns. The final composition of the solution is the main parameter to take in account. A process for nitrous gases retention using scubber columns containing H 2 O or diluted HNO 3 is presented. Chemiluminescence measurement was employed to NO x evalution before and after scrubbing. Gas flow, temperature, residence time are the main parameters considered in this paper. For the dissolution of 100g UO 2 in 8M nitric acid, a 6NL/h O 2 flow was the best condition for the NO/NO 2 oxidation with maximum adsorption in the scrubber columns. (author) [pt

  3. Vulvar Lobular Capillary Hemangioma (Pyogenic Granuloma

    Directory of Open Access Journals (Sweden)

    Kian-Mei Chong

    2005-03-01

    Conclusion: Pyogenic granuloma is considered a reactive hyperproliferative vascular response to trauma or other stimuli. The name “pyogenic granuloma” is a misnomer since the condition is not associated with pus and does not represent a granuloma histologically. There are a few cases of lobular capillary hemangioma of the glans penis but it is rare on the female genitalia. We present this case to help physicians become aware that lobular capillary hemangiomas may occur at this site.

  4. Simulation of capillary bridges between nanoscale particles.

    Science.gov (United States)

    Dörmann, Michael; Schmid, Hans-Joachim

    2014-02-04

    Capillary forces are very important as they exceed in general other adhesion forces. But at the same time the exact calculation of these forces is very complex, so often assumptions and approximations are used. Previous research was done with regard to micrometer sized particles, but the behavior of nanoscale particles is different. Hence, the results for micrometer sized particles cannot be directly transferred when considering nanoscale particles. Therefore, a simulation method was developed to calculate numerically the shape of a rotationally symmetrical capillary bridge between two spherical particles or a particle and a plate. The capillary bridge in the gap between the particles is formed due to capillary condensation and is in thermodynamic equilibrium with the gas phase. Hence the Kelvin equation and the Young-Laplace equation can be used to calculate the profile of the capillary bridge, depending on the relative humidity of the surrounding air. The bridge profile consists of several elements that are determined consecutively and interpolated linearly. After the shape is determined, the volume and force, divided into capillary pressure force and surface tension force, can be calculated. The validation of this numerical model will be shown by comparison with several different analytical calculations for micrometer-sized particles. Furthermore, it is demonstrated that two often used approximations, (1) the toroidal approximation and (2) the use of an effective radius, cannot be used for nanoscale particles without remarkable mistake. It will be discussed how the capillary force and its components depend on different parameters, like particle size, relative humidity, contact angle, and distance, respectively. The rupture of a capillary bridge due to particle separation will also be presented.

  5. Coatings of molecularly imprinted polymers based on polyhedral oligomeric silsesquioxane for open tubular capillary electrochromatography.

    Science.gov (United States)

    Zhao, Qing-Li; Zhou, Jin; Zhang, Li-Shun; Huang, Yan-Ping; Liu, Zhao-Sheng

    2016-05-15

    Polyhedral oligomeric silsesquioxane (POSS) was successfully applied, for the first time, to prepare imprinted monolithic coating for capillary electrochromatography. The imprinted monolithic coating was synthesized with a mixture of PSS-(1-Propylmethacrylate)-heptaisobutyl substituted (MA 0702), S-amlodipine (template), methacrylic acid (functional monomer), and 2-methacrylamidopropyl methacrylate (crosslinker), in a porogenic mixture of toluene-isooctane. The influence of synthesis parameters on the imprinting effect and separation performance, including the amount of MA 0702, the ratio of template to monomer, and the ratio of monomer to crosslinker, was investigated. The greatest resolution for enantiomers separation on the imprinted monolithic column prepared with MA 0702 was up to 22.3, about 2 times higher than that prepared in absence of the POSS. Column efficiency on the POSS-based MIP coatings was beyond 30,000 plate m(-1). The comparisons between MIP coating synthesized with the POSS and without the POSS were made in terms of selectivity, column efficiency, and resolution. POSS-based MIP capillaries with naproxen or zopiclone was also prepared and separation of enantiomers can be achieved. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Determination of DDTs and PCBs by capillary gas chromatography and electron capture detection

    International Nuclear Information System (INIS)

    1988-01-01

    This reference method deals with the determination of DDTs and PCBs in marine environmental samples using high resolution gas chromatography. Several other halogenated pesticides and other electron capturing organic compounds may be present in samples and many of these may also be determined by this method. Not all electron capturing residues will be resistant to all of the clean up procedures described here for the analysis of DTTs and PCBs. Therefore, additional information on the stability of some common pesticides using this methodology is also provided. The high separation power of open tubular (''capillary'') columns allows the identification and quantification of many compounds in the complex mixtures occurring in environmental samples. This manual provides information on the theoretical and practical aspects of the use of these high resolution columns for the analysis of DDTs and PCBs in environmental samples. The qualitative and quantitative method can be applied to any sample type (aerosol/vapour, water, particulates, biota, etc.) provided that suitable cleaned-up extracts dissolved in n-hexane are available for injection into the GC system. For example, methods for obtaining these cleaned-up sample extracts from marine organisms are described in detail in UNEP Reference Method no. 14 and for sediments in No. 17. The change in the field of application by analysing by capillary rather than packed columns may be less dramatic for DDTs. However, with the increased separation, the possibilities of inaccurate analysis resulting from overlap with interfering compounds is reduced. 7 refs, 1 fig., 3 tabs

  7. DNA Sequencing by Capillary Electrophoresis

    Science.gov (United States)

    Karger, Barry L.; Guttman, Andras

    2009-01-01

    Sequencing of human and other genomes has been at the center of interest in the biomedical field over the past several decades and is now leading toward an era of personalized medicine. During this time, DNA sequencing methods have evolved from the labor intensive slab gel electrophoresis, through automated multicapillary electrophoresis systems using fluorophore labeling with multispectral imaging, to the “next generation” technologies of cyclic array, hybridization based, nanopore and single molecule sequencing. Deciphering the genetic blueprint and follow-up confirmatory sequencing of Homo sapiens and other genomes was only possible by the advent of modern sequencing technologies that was a result of step by step advances with a contribution of academics, medical personnel and instrument companies. While next generation sequencing is moving ahead at break-neck speed, the multicapillary electrophoretic systems played an essential role in the sequencing of the Human Genome, the foundation of the field of genomics. In this prospective, we wish to overview the role of capillary electrophoresis in DNA sequencing based in part of several of our articles in this journal. PMID:19517496

  8. Capillary electrophoretic study of individual exocytotic events in single mast cells

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Andrea Ming-Wei [Iowa State Univ., Ames, IA (United States)

    1999-02-12

    The peak profile of individual degranulation events from the on-column release of serotonin from single rat peritoneal mast cells (RPMCs) was monitored using capillary electrophoresis with laser-induced native fluorescence detection (CE-LINF). Serotonin, an important biogenic amine, is contained in granules (0.25 fL) within RPMCs and is extruded by a process termed exocytosis. The secretagogue, Polymyxin B sulfate, was used as the CE running buffer after injection of a single RPMC into the separation capillary to stimulate the release of the granules. Because the release process occurs on a ms time scale, monitoring individual exocytotic events is possible with the coupling of high-speed CE and LINF detection.

  9. Development of high power pumping system for capillary discharge EUV laser

    International Nuclear Information System (INIS)

    Sakai, Yusuke; Komatsu, Takanori; Watanabe, Masato; Okino, Akitoshi; Hotta, Eiki

    2008-01-01

    Development of high power pumping system for capillary discharge soft X-ray laser is reported. The pulsed power system consists of a 2.2 μF LC generator, a 2:54 step-up transformer and a 3 nF water capacitor. Taking advantage of high efficiency configuration, step-up ratio of water capacitor voltage to LC generator initial voltage is about 40 times. Consequently, obtained water capacitor voltage reaches about 450 kV when LC generator was charged to 12.5 kV. As a consequent, possibility of charging a water capacitor to 1 MV is demonstrated. With this extremely compact system, discharge current could be increased to nearly 100 kA through moderately long capillary, which leads to generation of high-density and high-temperature plasma column in order to realize EUV laser. (author)

  10. Development of a multiplexed interface for capillary electrophoresis-electrospray ion trap mass spectrometry.

    Science.gov (United States)

    Li, Fu-An; Wu, Ming-Chi; Her, Guor-Rong

    2006-08-01

    A four-channel multiplexed electrospray capillary electrophoresis interface has been developed. This new interface permits up to four capillary electrophoresis columns to be sampled sequentially by means of a stepper motor and a notched rotating plate assembly, which at any instant occludes all but a single sprayer. In this design, four sheath liquid electrospray probes are oriented in a circular array situated 90 degrees relative to one another. The rotating metal disk, which contains a one-quarter notch, is mounted to the stepper motor assembly and is located between the sprayers and the entrance aperture of an ion trap mass spectrometer. By using the data acquisition signal from the ion trap mass spectrometer, the scan event is synchronized with the rotation of the metal disk. With this device, four discrete sample streams can be simultaneously analyzed, resulting in a 4-fold increase in analytical throughput.

  11. Determination of Betaine in Forsythia Suspensa by High Performance Capillary Electrophoresis

    Science.gov (United States)

    Liu, Haixing; Dong, Guoliang; Wang, Lintong

    2017-12-01

    This paper presents the determination of betaine content of Forsythia suspensa by high performance capillary electrophoresis (HPCE) method. The borax solution was chosen as buffer solution, and its concentration was 40 mmol with capillary column (75μm×52/60cm) at a constant voltage of 20kV and injecting pressure time of 10s at 20°C. Linearity was kept in the concent ration range of 0.0113-1.45mg·ml-1 of betaine with correlation coefficient of 0.999. The recovery was in the range of 97%-117% (n=5), The content of betaine was 281.5 mg·g-1and RSD value of 9.6% (n=6) in Forsythia suspensa. This method has the advantage of rapid, accurate and good repeatability in separation and determination of betaine in Forsythia suspensa.

  12. Cell adhesion during bullet motion in capillaries.

    Science.gov (United States)

    Takeishi, Naoki; Imai, Yohsuke; Ishida, Shunichi; Omori, Toshihiro; Kamm, Roger D; Ishikawa, Takuji

    2016-08-01

    A numerical analysis is presented of cell adhesion in capillaries whose diameter is comparable to or smaller than that of the cell. In contrast to a large number of previous efforts on leukocyte and tumor cell rolling, much is still unknown about cell motion in capillaries. The solid and fluid mechanics of a cell in flow was coupled with a slip bond model of ligand-receptor interactions. When the size of a capillary was reduced, the cell always transitioned to "bullet-like" motion, with a consequent decrease in the velocity of the cell. A state diagram was obtained for various values of capillary diameter and receptor density. We found that bullet motion enables firm adhesion of a cell to the capillary wall even for a weak ligand-receptor binding. We also quantified effects of various parameters, including the dissociation rate constant, the spring constant, and the reactive compliance on the characteristics of cell motion. Our results suggest that even under the interaction between P-selectin glycoprotein ligand-1 (PSGL-1) and P-selectin, which is mainly responsible for leukocyte rolling, a cell is able to show firm adhesion in a small capillary. These findings may help in understanding such phenomena as leukocyte plugging and cancer metastasis. Copyright © 2016 the American Physiological Society.

  13. Urea functionalized surface-bonded sol-gel coating for on-line hyphenation of capillary microextraction with high-performance liquid chromatography.

    Science.gov (United States)

    Jillani, Shehzada Muhammad Sajid; Alhooshani, Khalid

    2018-03-30

    Sol-gel urea functionalized-[bis(hydroxyethyl)amine] terminated polydimethylsiloxane coating was developed for capillary microextraction-high performance liquid chromatographic analysis from aqueous samples. A fused silica capillary is coated from the inside with surface bonded coating material and is created through in-situ sol-gel reaction. The urea-functionalized coating was immobilized to the inner surface of the capillary by the condensation reaction of silanol groups of capillary and sol-solution. The characterization of the coating material was successfully done by using X-ray photoelectron spectroscopy, thermogravimetric analysis, field emission scanning electron microscope, and energy dispersive X-ray spectrometer. To make a setup of online capillary microextraction-high performance liquid chromatography, the urea functionalized capillary was installed in the HPLC manual injection port. The analytes of interest were pre-concentrated in the coated sampling loop, desorbed by the mobile phase, chromatographically separated on C-18 column, and analyzed by UV detector. Sol-gel coated capillaries were used for online extraction and high-performance liquid chromatographic analysis of phenols, ketones, aldehydes, and polyaromatic hydrocarbons. This newly developed coating showed excellent extraction for a variety of analytes ranging from highly polar to non-polar in nature. The analysis using sol-gel coating showed excellent overall sensitivity in terms of lower detection limits (S/N = 3) for the analytes (0.10 ng mL -1 -14.29 ng mL -1 ) with acceptable reproducibility that is less than 12.0%RSD (n = 3). Moreover, the capillary to capillary reproducibility of the analysis was also tested by changing the capillary of the same size. This provided excellent%RSD of less than 10.0% (n = 3). Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Understanding capillary condensation and hysteresis in porous silicon: network effects within independent pores.

    Science.gov (United States)

    Naumov, Sergej; Khokhlov, Alexey; Valiullin, Rustem; Kärger, Jörg; Monson, Peter A

    2008-12-01

    The ability to exert a significant degree of pore structure control in porous silicon materials has made them attractive materials for the experimental investigation of the relationship between pore structure, capillary condensation, and hysteresis phenomena. Using both experimental measurements and a lattice gas model in mean field theory, we have investigated the role of pore size inhomogeneities and surface roughness on capillary condensation of N2 at 77K in porous silicon with linear pores. Our results resolve some puzzling features of earlier experimental work. We find that this material has more in common with disordered materials such as Vycor glass than the idealized smooth-walled cylindrical pores discussed in the classical adsorption literature. We provide strong evidence that this behavior comes from the complexity of the processes within independent linear pores, arising from the pore size inhomogeneities along the pore axis, rather than from cooperative effects between different pores.

  15. Aerosol penetration through capillaries and leaks: experimental studies on the influence of pressure

    International Nuclear Information System (INIS)

    Morton, D.A.V.; Mitchell, J.P.

    1995-01-01

    It is important to understand the movement of aerosols through ultrafine leak-paths with dimensions of similar order to the gas-borne particles when assessing the validity of leak-testing procedures for transport containers for radioactive materials. Experiments have been undertaken to investigate the penetration of micron-sized airborne particles using glass micro-capillaries as model leak-paths. Previous studies demonstrated a simple relationship between air leakage and total particle penetration rates at a constant driving pressure (100 kPa). The present work has demonstrated the importance of pressure in regulating the rate at which the leak-path is plugged by deposited particles. Much of this deposition appears to take place at the entrances of the capillaries where the air-flow converges. (author)

  16. Colloidal Asphaltene Deposition and Aggregation in Capillary Flow: Experiments and Mesoscopic Simulation

    Science.gov (United States)

    Boek, Edo S.; Ladva, Hemant K.; Crawshaw, John P.; Padding, Johan T.

    2008-07-01

    The aggregation and deposition of colloidal asphaltene in reservoir rock is a significant problem in the oil industry. To obtain a fundamental understanding of this phenomenon, we have studied the deposition and aggregation of colloidal asphaltene in capillary flow by experiment and simulation. For the simulation, we have used the stochastic rotation dynamics (SRD) method, in which the solvent hydrodynamic emerges from the collisions between the solvent particles, while the Brownian motion emerges naturally from the interactions between the colloidal asphaltene particles and the solvent. The asphaltene colloids interact through a screened Coulomb potential. We vary the well depth ɛ∝ and the flow rate v to obtain Peflow≫1 (hydrodynamic interactions dominate) and Re≪1 (Stokes flow). In the simulations, we impose a pressure drop over the capillary length and measure the corresponding solvent flow rate. We observe that the transient solvent flow rate decreases when the asphaltene particles become more "sticky". For a well depth ɛ∝ = 2kBT, a monolayer deposits on the capillary wall. With an increasing well depth, the capillary becomes totally blocked. The clogging is transient for ɛ∝ = 5kBT, but appears to be permanent for ɛ∝ = 10-20 kBT. We compare our simulation results with flow experiments in glass capillaries, where we use extracted asphaltenes in toluene, reprecipitated with n-heptane. In the experiments, the dynamics of asphaltene precipitation and deposition were monitored in a slot capillary using optical microscopy under flow conditions similar to those used in the simulation. Maintaining a constant flow rate of 5 μL min-1, we found that the pressure drop across the capillary first increased slowly, followed by a sharp increase, corresponding to a complete local blockage of the capillary. Doubling the flow rate to 10 μL min-1, we observe that the initial deposition occurs faster but the deposits are subsequently entrained by the flow. We

  17. Highly crosslinked polymeric monoliths for reversed-phase capillary liquid chromatography of small molecules.

    Science.gov (United States)

    Liu, Kun; Tolley, H Dennis; Lee, Milton L

    2012-03-02

    Seven crosslinking monomers, i.e., 1,3-butanediol dimethacrylate (1,3-BDDMA), 1,4-butanediol dimethacrylate (1,4-BDDMA), neopentyl glycol dimethacrylate (NPGDMA), 1,5-pentanediol dimethacrylate (1,5-PDDMA), 1,6-hexanediol dimethacrylate (1,6-HDDMA), 1,10-decanediol dimethacrylate (1,10-DDDMA), and 1,12-dodecanediol dimethacrylate (1,12-DoDDMA), were used to synthesize highly cross-linked monolithic capillary columns for reversed-phase liquid chromatography (RPLC) of small molecules. Dodecanol and methanol were chosen as "good" and "poor" porogenic solvents, respectively, for these monoliths, and were investigated in detail to provide insight into the selection of porogen concentration using 1,12-DoDDMA. Isocratic elution of alkylbenzenes at a flow rate of 300 nL/min was conducted for all of the monoliths. Gradient elution of alkylbenzenes and alkylparabens provided high resolution separations. Optimized monoliths synthesized from all seven crosslinking monomers showed high permeability. Several of the monoliths demonstrated column efficiencies in excess of 50,000 plates/m. Monoliths with longer alkyl-bridging chains showed very little shrinking or swelling in solvents of different polarities. Column preparation was highly reproducible; the relative standard deviation (RSD) values (n=3) for run-to-run and column-to-column were less than 0.25% and 1.20%, respectively, based on retention times of alkylbenzenes. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Ultrafast preparation of a polyhedral oligomeric silsesquioxane-based ionic liquid hybrid monolith via photoinitiated polymerization, and its application to capillary electrochromatography of aromatic compounds.

    Science.gov (United States)

    Zhang, Bingyu; Lei, Xiaoyun; Deng, Lijun; Li, Minsheng; Yao, Sicong; Wu, Xiaoping

    2018-06-06

    An ionic liquid hybrid monolithic capillary column was prepared within 7 min via photoinitiated free-radical polymerization of an ionic liquid monomer (1-butyl-3-vinylimidazolium-bis[(trifluoromethyl)sulfonyl]imide); VBIMNTF 2 ) and a methacryl substituted polyhedral oligomeric silsesquioxane (POSS-MA) acting as a cross-linker. The effects of composition of prepolymerization solution and initiation time on the porous structure and electroosmotic flow (EOF) of monolithic column were investigated. The hybrid monolith was characterized by scanning electron microscopy and FTIR. Owing to the introduction of a rigid nanosized POSS silica core and ionic liquids with multiple interaction sites, the monolithic column has a well-defined 3D skeleton morphology, good mechanical stability, and a stable anodic electroosmotic flow. The hybrid monolithic stationary phase was applied to the capillary electrochromatographic separation of various alkylbenzenes, phenols, anilines and polycyclic aromatic hydrocarbons (PAHs). The column efficiency is highest (98,000 plates/m) in case of alkylbenzenes. Mixed-mode retention mechanisms including hydrophobic interactions, π-π stacking, electrostatic interaction and electrophoretic mobility can be observed. This indicates the potential of this material in terms of efficient separation of analytes of different structural type. Graphical Abstract Preparation of a mixed-mode ionic liquid hybrid monolithic column via photoinitiated polymerization of methacryl substituted polyhedral oligomeric silsesquioxane (POSS-MA) and 1-butyl-3-vinylimidazolium-bis[(trifluoromethyl)sulfonyl]imide (VBIMNTF 2 ) ionic liquid for use in capillary electrochromatography.

  19. lead glass brick

    CERN Multimedia

    When you look through the glass at a picture behind, the picture appears raised up because light is slowed down in the dense glass. It is this density (4.06 gcm-3) that makes lead glass attractive to physicists. The refractive index of the glass is 1.708 at 400nm (violet light), meaning that light travels in the glass at about 58% its normal speed. At CERN, the OPAL detector uses some 12000 blocks of glass like this to measure particle energies.

  20. Preparation and evaluation of a novel hybrid monolithic column based on pentafluorobenzyl imidazolium bromide ionic liquid.

    Science.gov (United States)

    Shan, Yuanhong; Qiao, Lizhen; Shi, Xianzhe; Xu, Guowang

    2015-01-02

    To develop a novel hybrid monolithic column based on pentafluorobenzyl imidazolium bromide ionic liquid, a new ionic liquid monomer was synthesized from 1-vinylimidazole and pentafluorobenzyl bromide. By employing a facile one-step copolymerization of polyhedral-oligomeric-silsesquioxane-type (POSS) cross-linking agent and the home-made ionic liquid monomer, the hybrid monolithic columns were in situ fabricated in fused-silica capillary. The morphology of monolithic column was characterized by scanning electron microscope (SEM) and the chemical composition was confirmed by Fourier-transform infrared spectroscopy (FT-IR) and elemental analysis. Excellent mechanical stability and slight swelling propensity were exhibited which was ascribed to the rigid hybrid monolithic skeleton. Reproducibility results of run-to-run, column-to-column, batch-to-batch and day-to-day were investigated and the RSDs were less than 0.46%, 1.84%, 3.96% and 3.17%, respectively. The mixed-mode retention mechanism with hydrophobic interaction, π-π stacking, ion-exchange, electrostatic interaction and dipole-dipole interaction was explored systematically using analytes with different structure types. Satisfied separation capability and column efficiency were achieved for the analysis of small molecular compounds such as alkylbenzenes, polycyclic aromatic hydrocarbons, nucleosides and halogenated compounds. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. A High Position Resolution X-ray Detector: an Edge on Illuminated Capillary Plate Combined with a Gas Amplification Structure

    CERN Document Server

    Iacobaeus, C.; Lund-Jensen, B.; Ostling, J.; Pavlopoulos, P.; Peskov, V.; Tokanai, F.

    2006-01-01

    We have developed and successfully tested a prototype of a new type of high position resolution hybrid X-ray detector. It contains a thin wall lead glass capillary plate converter of X-rays combined with a microgap parallel-plate avalanche chamber filled with gas at 1 atm. The operation of these converters was studied in a wide range of X-ray energies (from 6 to 60 keV) at incident angles varying from 0-90 degree. The detection efficiency, depending on the geometry, photon energy, incident angle and the mode of operation, was between 5-30 percent in a single step mode and up to 50 percent in a multi-layered combination. Depending on the capillary geometry, the position resolution achieved was between 0.050-0.250 mm in digital form and was practically independent of the photon energy or gas mixture. The usual lead glass capillary plates operated without noticeable charging up effects at counting rates of 50 Hz/mm2, and hydrogen treated capillaries up to 10E5 Hz/mm2. The developed detector may open new possibil...

  2. Analysis of an industrial process simulator column using third-generation computed tomography

    International Nuclear Information System (INIS)

    Kirita, Rodrigo; Carvalho, Diego Vergacas de Sousa; Mesquita, Carlos Henrique de; Vasquez, Pablo Antonio S.; Hamada, Margarida Mizue

    2011-01-01

    The CT methodology must be tested using a simulator column in the laboratory before applying it in the industrial plants. In this work, using the third-generation industrial computed tomography developed at the IPEN, a gas absorption column, used as a simulator column for industrial process was evaluated. It is a glass cylindrical tube of 90 mm diameter and 1400 mm height constituted the following parts: random packed column, liquid circuit (water), gas circuit and analysis was used as a simulator column. Gamma ray tomography experiments were carried out, using this simulator column empty and filled with water. In this work the scanner was setting for 90 views and 19 projections for each detector totalizing 11970 projections. The resulting images describe the presence of liquid or gas phases and are possible to evaluate the linear attenuation coefficients inside the column. In this case, linear attenuation coefficient for water was 0.0813 cm-1. It was established that the newly developed third-generation fan-beam arrangement gamma scanner unit has a good spatial resolution acceptable given the size of the column used in this study. (author)

  3. Radio Column Chromatographic Assay of H3-Labelled Substances

    International Nuclear Information System (INIS)

    Scharpenseel, H.W.; Menke, K.H.

    1962-01-01

    Combined radio-chromatographic investigations of H 3 -labelled substances are an integral part of the majority of biochemical experiments with H 3 -labelled compounds. H 3 -radio paper chromatography yields, in a scanner with a windowless flow counter, a counting efficiency of 0,5 -1,5%, depending largely on the thickness of the paper and the self-absorption of the labelled compound. The radio gas chromatography of tritiated compounds presents no major problem. Successful use is being made of a combination of a gas chromatograph with a flow ionization chamber and vibrating reed electrometer, a system originated by K. E. Wilzbach and P. Riessz, and improved by H. Dutton, L. Mason and L. Blair. Through the use of ''Teflon'' and silicone-rubber for the insulating parts of the flow ion chamber, it can be operated at close to 300 o C. Radio column chromatography with tritium holds little promise, when the column effluent is spread out as a shallow layer and slowly passes under a windowless flow counter or a scintillation counter, as was successfully tried with C 14 . Liquid scintillation spectrometry is likely to be the chosen method. Essentially, there are two different approaches feasible. These have been compared: 1. The column effluent is passed through a coil of plastic scintillator tubing, which is wound around a ''Plexiglas'' cylinder and placed in a bath of silicone oil in a light pipe with TiO 2 -reflector. Similarly, the HP-containing effluent can be directed through a test vial, filled - very much as in Steinberg's method - with plastic scintillator beads. These two approaches, that operate highly satisfactorily in the case of C 14 , offer low counting efficiencies of less than 1% for H 3 due to the unfavourable surface to volume ratio. 2. The column effluent is combined 1:30 with a mixture of 3:2 toluene/ethanol by the action of a magnet-vibrator before being assayed while passing through a K 40 -free glass - coiled between the analyser- and monitor

  4. Chromatographic properties PLOT multicapillary columns.

    Science.gov (United States)

    Nikolaeva, O A; Patrushev, Y V; Sidelnikov, V N

    2017-03-10

    Multicapillary columns (MCCs) for gas chromatography make it possible to perform high-speed analysis of the mixtures of gaseous and volatile substances at a relatively large amount of the loaded sample. The study was performed using PLOT MCCs for gas-solid chromatography (GSC) with different stationary phases (SP) based on alumina, silica and poly-(1-trimethylsilyl-1-propyne) (PTMSP) polymer as well as porous polymers divinylbenzene-styrene (DVB-St), divinylbenzene-vinylimidazole (DVB-VIm) and divinylbenzene-ethylene glycol dimethacrylate (DVB-EGD). These MCCs have the efficiency of 4000-10000 theoretical plates per meter (TP/m) and at a column length of 25-30cm can separate within 10-20s multicomponent mixtures of substances belonging to different classes of chemical compounds. The sample amount not overloading the column is 0.03-1μg and depends on the features of a porous layer. Examples of separations on some of the studied columns are considered. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Steroids in porcine follicular fluid: analysis by HPLC, capillary CG and capillary CG/MS after purification on SEP-PAK C18 and ion exchange chromatography.

    Science.gov (United States)

    Khalil, M W; Lawson, V

    1983-04-01

    Steroids in porcine follicular fluid have been concentrated by reverse phase chromatography in SEP-PAK C18 and purified further on the cation exchanger SP-Sephadex C-25. Fractionation into unconjugated neutral and phenolic steroids, glucuronides and sulfates was carried out on triethylaminohydroxypropyl Sephadex LH-20 (TEAP-LH-20). The unconjugated neutral fraction was analysed by high pressure liquid chromatography (HPLC) on a C18 radial cartridge 5 mm I.D.; 10 mu, or on a C18 5 mu RESOLVE column, and by capillary gas chromatography (GC) on a 12 M OV-1 cross linked fused silica column. Testosterone, progesterone and androstenedione were the major steroids detected by HPLC monitored at 254 nm, although 17- hydroxy-, 20 alpha-dihydro- and 20 beta-dihydroprogesterone were also present. Pregnenolone, pregnanediol, dehydroepiandrosterone, 17-hydroxypregnenolone and androsterone were detected by capillary CG as their 0-methyloxime trimethylsilyether derivatives. Further confirmation of structure was provided by complete mass spectral data or by selective ion monitoring (SIM).

  6. Transport of Butane in a Porous Vycor Glass Membrane in the Region of Condensation Pressure.

    Czech Academy of Sciences Publication Activity Database

    Uchytil, Petr; Petričkovič, Roman; Seidel-Morgenstern, A.

    2007-01-01

    Roč. 293, 1-2 (2007) , s. 15-21 ISSN 0376-7388 R&D Projects: GA AV ČR(CZ) IAA4072402 Institutional research plan: CEZ:AV0Z40720504 Keywords : mass transport * porous vycor glass * capillary condensation Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.432, year: 2007

  7. Impaired skin capillary recruitment in essential hypertension is caused by both functional and structural capillary rarefaction

    NARCIS (Netherlands)

    Serne, EH; Gans, ROB; ter Maaten, JC; Tangelder, GJ; Donker, AJM; Stehouwer, CDA

    Capillary rarefaction occurs in many tissues in patients with essential hypertension and may contribute to an increased vascular resistance and impaired muscle metabolism. Rarefaction may be caused by a structural (anatomic) absence of capillaries, functional nonperfusion, or both. The aim of this

  8. CEC-atmospheric pressure ionization MS of pesticides using a surfactant-bound monolithic column.

    Science.gov (United States)

    Gu, Congying; Shamsi, Shahab A

    2010-04-01

    A surfactant bound poly (11-acrylaminoundecanoic acid-ethylene dimethacrylate) monolithic column was simply prepared by in situ co-polymerization of 11-acrylaminoundecanoic acid and ethylene dimethacrylate with 1-propanol, 1,4-butanediol and water as porogens in 100 microm id fused-silica capillary in one step. This column was used in CEC-atmospheric pressure photoionization (APPI)-MS system for separation and detection of N-methylcarbamates pesticides. Numerous parameters are optimized for CEC-APPI-MS. After evaluation of the mobile phase composition, sheath liquid composition and the monolithic capillary outlet position, a fractional factorial design was selected as a screening procedure to identify factors of ionization source parameters, such as sheath liquid flow rate, drying gas flow rate, drying gas temperature, nebulizing gas pressure, vaporizer temperature and capillary voltage, which significantly influence APPI-MS sensitivity. A face-centered central composite design was further utilized to optimize the most significant parameters and predict the best sensitivity. Under optimized conditions, S/Ns around 78 were achieved for an injection of 100 ng/mL of each pesticide. Finally, this CEC-APPI-MS method was successfully applied to the analysis of nine N-methylcarbamates in spiked apple juice sample after solid phase extraction with recoveries in the range of 65-109%.

  9. Glass and nuclear wastes

    International Nuclear Information System (INIS)

    Sombret, C.

    1982-10-01

    Glass shows interesting technical and economical properties for long term storage of solidified radioactive wastes by vitrification or embedding. Glass composition, vitrification processes, stability under irradiation, thermal stability and aqueous corrosion are studied [fr

  10. Microstructuring of glasses

    CERN Document Server

    Hülsenberg, Dagmar; Bismarck, Alexander

    2008-01-01

    As microstructured glass becomes increasingly important for microsystems technology, the main application fields include micro-fluidic systems, micro-analysis systems, sensors, micro-actuators and implants. And, because glass has quite distinct properties from silicon, PMMA and metals, applications exist where only glass devices meet the requirements. The main advantages of glass derive from its amorphous nature, the precondition for its - theoretically - direction-independent geometric structurability. Microstructuring of Glasses deals with the amorphous state, various glass compositions and their properties, the interactions between glasses and the electromagnetic waves used to modify it. Also treated in detail are methods for influencing the geometrical microstructure of glasses by mechanical, chemical, thermal, optical, and electrical treatment, and the methods and equipment required to produce actual microdevices.

  11. Measurement of optical glasses

    International Nuclear Information System (INIS)

    Nicolau-Rebigan, S.

    1978-11-01

    The possibilities of measurement of the optical glasses parameters needed in building optical devices especially in lasers devices are presented. In the first chapter the general features of the main optical glasses as well as the modalities of obtaining them are given. Chapter two defines the optical glass parameters, and the third chapter describes the measuring methods of the optical glass parameters. Finally, the conclusions which point out the utilization of this paper are presented. (author)

  12. Study of capillary tracking detectors with position-sensitive photomultiplier readout

    International Nuclear Information System (INIS)

    Cardini, A.; Cavasinni, V.; Di Girolamo, B.; Dolinsky, S.I.; Flaminio, V.; Golovkin, S.V.; Gorin, A.M.; Medvedkov, A.M.; Pyshev, A.I.; Tyukov, V.E.; Vasilchenko, V.G.; Zymin, K.V.

    1995-01-01

    Measurements have been carried out on light yield and attenuation length in glass capillaries filled with new liquid scintillators (LS) and compared with analogous measurements made on 0.5 mm diameter plastic fibres Kuraray SCSF-38 and 3HF. It is found that, at a distance of 1 m, the light output in the capillary filled with green LS based on 1-methylnaphthalene doped with a new dye 3M15 is greater by a factor of 2 to 3 than for plastic fibres. A tracking detector consisting of a capillary bundle read out by a 100 channel position-sensitive microchannel plate photomultiplier (2MCP-100) has been built and tested in the laboratory using a cosmic ray trigger. A comparison has been made between the performance of such a detector and that of a similar one, read out by a 96 channel Philips XP1724/A photomultiplier. It was found that a bundle made of 20μm diameter capillaries with a tapered end giving a magnification of 2.56, filled with the new IPN+3M15 liquid scintillator, read out by the 2MCP-100, provides a space resolution of σ=170μm, a two-track resolution of the same value and a hit density of n=1.9/mm for tracks crossing the detector at a distance of 20 cm from the photocathode. If the same detector is read out by the Philips XP1724/A, the space resolution becomes 200μm, the two-track resolution 600μm and the hit density n=1.7/mm. The worse performance in the latter case is caused by the larger crosstalk compared with that of the 2MCP-100 PSPM. The results indicate that a LS-filled capillary detector is a very promising device for fast fibre tracking. (orig.)

  13. Two-dimensional liquid chromatography consisting of twelve second-dimension columns for comprehensive analysis of intact proteins.

    Science.gov (United States)

    Ren, Jiangtao; Beckner, Matthew A; Lynch, Kyle B; Chen, Huang; Zhu, Zaifang; Yang, Yu; Chen, Apeng; Qiao, Zhenzhen; Liu, Shaorong; Lu, Joann J

    2018-05-15

    A comprehensive two-dimensional liquid chromatography (LCxLC) system consisting of twelve columns in the second dimension was developed for comprehensive analysis of intact proteins in complex biological samples. The system consisted of an ion-exchange column in the first dimension and the twelve reverse-phase columns in the second dimension; all thirteen columns were monolithic and prepared inside 250 µm i.d. capillaries. These columns were assembled together through the use of three valves and an innovative configuration. The effluent from the first dimension was continuously fractionated and sequentially transferred into the twelve second-dimension columns, while the second-dimension separations were carried out in a series of batches (six columns per batch). This LCxLC system was tested first using standard proteins followed by real-world samples from E. coli. Baseline separation was observed for eleven standard proteins and hundreds of peaks were observed for the real-world sample analysis. Two-dimensional liquid chromatography, often considered as an effective tool for mapping proteins, is seen as laborious and time-consuming when configured offline. Our online LCxLC system with increased second-dimension columns promises to provide a solution to overcome these hindrances. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Micro-fabricated packed gas chromatography column based on laser etching technology.

    Science.gov (United States)

    Sun, J H; Guan, F Y; Zhu, X F; Ning, Z W; Ma, T J; Liu, J H; Deng, T

    2016-01-15

    In this work, a micro packed gas chromatograph column integrated with a micro heater was fabricated by using laser etching technology (LET) for analyzing environmental gases. LET is a powerful tool to etch deep well-shaped channels on the glass wafer, and it is the most effective way to increase depth of channels. The fabricated packed GC column with a length of over 1.6m, to our best knowledge, which is the longest so far. In addition, the fabricated column with a rectangular cross section of 1.2mm (depth) × 0.6mm (width) has a large aspect ratio of 2:1. The results show that the fabricated packed column had a large sample capacity, achieved a separation efficiency of about 5800 plates/m and eluted highly symmetrical Gaussian peaks. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Micro-injector for capillary electrophoresis.

    Science.gov (United States)

    Sáiz, Jorge; Koenka, Israel Joel; García-Ruiz, Carmen; Müller, Beat; Chwalek, Thomas; Hauser, Peter C

    2015-08-01

    A novel micro-injector for capillary electrophoresis for the handling of samples with volumes down to as little as 300 nL was designed and built in our laboratory for analyses in which the available volume is a limitation. The sample is placed into a small cavity located directly in front of the separation capillary, and the injection is then carried out automatically by controlled pressurization of the chamber with compressed air. The system also allows automated flushing of the injection chamber as well as of the capillary. In a trial with a capillary electrophoresis system with contactless conductivity detector, employing a capillary of 25 μm diameter, the results showed good stability of migration times and peak areas. To illustrate the technique, the fast separation of five inorganic cations (Na(+) , K(+) , NH4 (+) , Ca(2+) , and Mg(2+) ) was set up. This could be achieved in less than 3 min, with good limits of detection (10 μM) and linear ranges (between about 10 and 1000 μM). The system was demonstrated for the determination of the inorganic cations in porewater samples of a lake sediment core. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Mechanically reinforced glass beams

    DEFF Research Database (Denmark)

    Nielsen, Jens Henrik; Olesen, John Forbes

    2007-01-01

    laminated float glass beam is constructed and tested in four-point bending. The beam consist of 4 layers of glass laminated together with a slack steel band glued onto the bottom face of the beam. The glass parts of the tested beams are \\SI{1700}{mm} long and \\SI{100}{mm} high, and the total width of one...

  17. Capillary pressure-saturation relationships for porous granular materials: Pore morphology method vs. pore unit assembly method

    Science.gov (United States)

    Sweijen, Thomas; Aslannejad, Hamed; Hassanizadeh, S. Majid

    2017-09-01

    In studies of two-phase flow in complex porous media it is often desirable to have an estimation of the capillary pressure-saturation curve prior to measurements. Therefore, we compare in this research the capability of three pore-scale approaches in reproducing experimentally measured capillary pressure-saturation curves. To do so, we have generated 12 packings of spheres that are representative of four different glass-bead packings and eight different sand packings, for which we have found experimental data on the capillary pressure-saturation curve in the literature. In generating the packings, we matched the particle size distributions and porosity values of the granular materials. We have used three different pore-scale approaches for generating the capillary pressure-saturation curves of each packing: i) the Pore Unit Assembly (PUA) method in combination with the Mayer and Stowe-Princen (MS-P) approximation for estimating the entry pressures of pore throats, ii) the PUA method in combination with the hemisphere approximation, and iii) the Pore Morphology Method (PMM) in combination with the hemisphere approximation. The three approaches were also used to produce capillary pressure-saturation curves for the coating layer of paper, used in inkjet printing. Curves for such layers are extremely difficult to determine experimentally, due to their very small thickness and the presence of extremely small pores (less than one micrometer in size). Results indicate that the PMM and PUA-hemisphere method give similar capillary pressure-saturation curves, because both methods rely on a hemisphere to represent the air-water interface. The ability of the hemisphere approximation and the MS-P approximation to reproduce correct capillary pressure seems to depend on the type of particle size distribution, with the hemisphere approximation working well for narrowly distributed granular materials.

  18. Hysteretic growth and decay of a waterspout column

    Science.gov (United States)

    Naumov, Igor V.; Herrada, Miguel A.; Sharifullin, Bulat R.; Shtern, Vladimir N.

    2018-02-01

    This work explores a model waterspout: a flow of water and sunflower oil driven by the rotating lid in a sealed vertical cylindrical container. The experiments reveal the hysteretic growth and decay of a water column. The numerical simulations uncover vortex breakdown (VB) in the water and oil flows. As the rotation speeds up, (1) a VB water cell emerges near the bottom center, (2) it expands and occupies almost the entire water volume except a thin layer adjusted to the interface, (3) a VB oil cell emerges and disappears above the interface-axis intersection, (4) the interface rises near the axis, descends at the periphery, and shifts from the sidewall to the bottom, (5) the water touches the lid near the axis and forms a column, extending from the bottom up to the lid. As the rotation decelerates, the process reverses, but the flow states differ from those for the direct process at same rotation speeds. It is argued that the hysteresis is a capillary phenomenon and occurs because the interface-wall contact angle differs in the direct and reverse processes.

  19. Modeling of column apparatus processes

    CERN Document Server

    Boyadjiev, Christo; Boyadjiev, Boyan; Popova-Krumova, Petya

    2016-01-01

    This book presents a new approach for the modeling of chemical and interphase mass transfer processes in industrial column apparatuses, using convection-diffusion and average-concentration models. The convection-diffusion type models are used for a qualitative analysis of the processes and to assess the main, small and slight physical effects, and then reject the slight effects. As a result, the process mechanism can be identified. It also introduces average concentration models for quantitative analysis, which use the average values of the velocity and concentration over the cross-sectional area of the column. The new models are used to analyze different processes (simple and complex chemical reactions, absorption, adsorption and catalytic reactions), and make it possible to model the processes of gas purification with sulfur dioxide, which form the basis of several patents.

  20. ADVANCED DIAGNOSTIC TECHNIQUES FOR THREE-PHASE SLURRY BUBBLE COLUMN REACTORS(SBCR)

    Energy Technology Data Exchange (ETDEWEB)

    M.H. Al-Dahhan; L.S. Fan; M.P. Dudukovic

    2002-07-25

    This report summarizes the accomplishment made during the third year of this cooperative research effort between Washington University, Ohio State University and Air Products and Chemicals. Data processing of the performed Computer Automated Radioactive Particle Tracking (CARPT) experiments in 6 inch column using air-water-glass beads (150 {micro}m) system has been completed. Experimental investigation of time averaged three phases distribution in air-Therminol LT-glass beads (150 {micro}m) system in 6 inch column has been executed. Data processing and analysis of all the performed Computed Tomography (CT) experiments have been completed, using the newly proposed CT/Overall gas holdup methodology. The hydrodynamics of air-Norpar 15-glass beads (150 {micro}m) have been investigated in 2 inch slurry bubble column using Dynamic Gas Disengagement (DGD), Pressure Drop fluctuations, and Fiber Optic Probe. To improve the design and scale-up of bubble column reactors, a correlation for overall gas holdup has been proposed based on Artificial Neural Network and Dimensional Analysis.

  1. Studies of column supported towers

    International Nuclear Information System (INIS)

    Chauvel, D.; Costaz, J.-L.

    1991-01-01

    As a result of a research and development programme into the civil engineering of cooling towers launched in 1978 by Electricite de France, very high cooling towers were built at Golfech and Chooz, in France, using column supports. This paper discusses the evolution of this new type of support from classical diagonal supports, presents some of the results of design calculations and survey measurements taken during construction of the shell and analyses the behaviour of the structure. (author)

  2. Recent applications of nanomaterials in capillary electrophoresis.

    Science.gov (United States)

    González-Curbelo, Miguel Ángel; Varela-Martínez, Diana Angélica; Socas-Rodríguez, Bárbara; Hernández-Borges, Javier

    2017-10-01

    Nanomaterials have found an important place in Analytical Chemistry and, in particular, in Separation Science. Among them, metal-organic frameworks, magnetic and non-magnetic nanoparticles, carbon nanotubes and graphene, as well as their combinations, are the most important nanomaterials that have been used up to now. Concerning capillary electromigration techniques, these nanomaterials have also been used as both pseudostationary phases in electrokinetic chromatography (EKC) and as stationary phases in microchip capillary electrophoresis (CE) and capillary electrochromatography (CEC), as a result of their interesting and particular properties. This review article pretends to provide a general and critical revision of the most recent applications of nanomaterials in this field (period 2010-2017). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. SPEEDUPtrademark ion exchange column model

    International Nuclear Information System (INIS)

    Hang, T.

    2000-01-01

    A transient model to describe the process of loading a solute onto the granular fixed bed in an ion exchange (IX) column has been developed using the SpeedUptrademark software package. SpeedUp offers the advantage of smooth integration into other existing SpeedUp flowsheet models. The mathematical algorithm of a porous particle diffusion model was adopted to account for convection, axial dispersion, film mass transfer, and pore diffusion. The method of orthogonal collocation on finite elements was employed to solve the governing transport equations. The model allows the use of a non-linear Langmuir isotherm based on an effective binary ionic exchange process. The SpeedUp column model was tested by comparing to the analytical solutions of three transport problems from the ion exchange literature. In addition, a sample calculation of a train of three crystalline silicotitanate (CST) IX columns in series was made using both the SpeedUp model and Purdue University's VERSE-LC code. All test cases showed excellent agreement between the SpeedUp model results and the test data. The model can be readily used for SuperLigtrademark ion exchange resins, once the experimental data are complete

  4. Fluoride glass fiber optics

    CERN Document Server

    Aggarwal, Ishwar D

    1991-01-01

    Fluoride Glass Fiber Optics reviews the fundamental aspects of fluoride glasses. This book is divided into nine chapters. Chapter 1 discusses the wide range of fluoride glasses with an emphasis on fluorozirconate-based compositions. The structure of simple fluoride systems, such as BaF2 binary glass is elaborated in Chapter 2. The third chapter covers the intrinsic transparency of fluoride glasses from the UV to the IR, with particular emphasis on the multiphonon edge and electronic edge. The next three chapters are devoted to ultra-low loss optical fibers, reviewing methods for purifying and

  5. Multiple Glass Ceilings

    OpenAIRE

    Russo, Giovanni; Hassink, Wolter

    2011-01-01

    Both vertical (between job levels) and horizontal (within job levels) mobility can be sources of wage growth. We find that the glass ceiling operates at both margins. The unexplained part of the wage gap grows across job levels (glass ceiling at the vertical margin) and across the deciles of the intra-job-level wage distribution (glass ceiling at the horizontal margin). This implies that women face many glass ceilings, one for each job level above the second, and that the glass ceiling is a p...

  6. Homogeneity of Inorganic Glasses

    DEFF Research Database (Denmark)

    Jensen, Martin; Zhang, L.; Keding, Ralf

    2011-01-01

    Homogeneity of glasses is a key factor determining their physical and chemical properties and overall quality. However, quantification of the homogeneity of a variety of glasses is still a challenge for glass scientists and technologists. Here, we show a simple approach by which the homogeneity...... of different glass products can be quantified and ranked. This approach is based on determination of both the optical intensity and dimension of the striations in glasses. These two characteristic values areobtained using the image processing method established recently. The logarithmic ratio between...

  7. Capillary interactions in nano-particle suspensions

    International Nuclear Information System (INIS)

    Bossev, D.P.; Warren, G.

    2009-01-01

    We have investigated the structures formed by colloidal particles suspended in solvents at volume fractions below 10% and interacting through capillary bridges. Such systems resemble colloidal gas of sticky nano-spheres that form pearl-necklace like chains that, in turn, induce strong viscoelasticity due to the formation of 3-D fractal network. The capillary force dominates the electrostatic and Van der Waals forces in solutions and can bridge multiple particles depending of the volume of the capillary bridge. We have investigated the morphology of the structures formed at different fractions of the bridging fluid. Small-angle neutron scattering (SANS) is used to study nanoparticles with an average diameter of 10 nm in polar and non-polar organic solvents at ambient temperatures. SANS intensity as a function of the scattering vector is analyzed as a product of a form factor, that depends on the particle shape, and a structure factor, that characterizes the interparticle inter reactions. The interaction of particles in polar solvents is considered to be through electrostatic repulsion and the data is successfully fitted by Hayter-Penfold mean spherical approximation (HPMSA). Computer simulations of a pearl necklace-like chain of spheres is conducted to explain the structure factor when capillary bridges are present. Alternatively, we have analyzed the slope of the intensity at low scattering vector in a double logarithmic plot to determine the dimension of the fractal structures formed by the particles at different volume fraction of the bridging fluid. We have also studied the properties of the capillary bridge between a pair of particles. The significance of this study is to explore the possibility of using capillary force as a tool to engineer new colloidal structures and materials in solutions and to optimize their viscoelastic properties. (author)

  8. Isothermal and non-isothermal infiltration and deuterium transport: a case study in a soil column from a headwater catchment

    Czech Academy of Sciences Publication Activity Database

    Sobotková, M.; Sněhota, M.; Budínová, E.; Tesař, Miroslav

    2017-01-01

    Roč. 65, č. 3 (2017), s. 234-243 ISSN 0042-790X Grant - others:GA ČR(CZ) GA14-03691S Institutional support: RVO:67985874 Keywords : isothermal infiltration * non-isothermal infiltration * column leaching * breakthrough curve * deuterium * viscosity * capillary trapping * entrapped air * permeability Subject RIV: DA - Hydrology ; Limnology OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 1.654, year: 2016

  9. Evolution in miniaturized column liquid chromatography instrumentation and applications: An overview.

    Science.gov (United States)

    Nazario, Carlos E D; Silva, Meire R; Franco, Maraíssa S; Lanças, Fernando M

    2015-11-20

    The purpose of this article is to underline the miniaturized LC instrumental system and describe the evolution of commercially available systems by discussing their advantages and drawbacks. Nowadays, there are already many miniaturized LC systems available with a great variety of pump design, interface and detectors as well as efficient columns technologies and reduced connections devices. The solvent delivery systems are able to drive the mobile phase without flow splitters and promote gradient elution using either dual piston reciprocating or syringe-type pumps. The mass spectrometry as detection system is the most widely used detection system; among many alternative ionization sources direct-EI LC-MS is a promising alternative to APCI. In addition, capillary columns are now available showing many possibilities of stationary phases, inner diameters and hardware materials. This review provides a discussion about miniaturized LC demonstrating fundamentals and instrumentals' aspects of the commercially available miniaturized LC instrumental system mainly nano and micro LC formats. This review also covers the recent developments and trends in instrumentation, capillary and nano columns, and several applications of this very important and promising field. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Validation of capillary blood analysis and capillary testing mode on the epoc Point of Care system

    Directory of Open Access Journals (Sweden)

    Jing Cao

    2017-12-01

    Full Text Available Background: Laboratory test in transport is a critical component of patient care, and capillary blood is a preferred sample type particularly in children. This study evaluated the performance of capillary blood testing on the epoc Point of Care Blood Analysis System (Alere Inc. Methods: Ten fresh venous blood samples was tested on the epoc system under the capillary mode. Correlation with GEM 4000 (Instrumentation Laboratory was examined for Na+, K+, Cl-, Ca2+, glucose, lactate, hematocrit, hemoglobin, pO2, pCO2, and pH, and correlation with serum tested on Vitros 5600 (Ortho Clinical Diagnostics was examined for creatinine. Eight paired capillary and venous blood was tested on epoc and ABL800 (Radiometer for the correlation of Na+, K+, Cl-, Ca2+, glucose, lactate, hematocrit, hemoglobin, pCO2, and pH. Capillary blood from 23 apparently healthy volunteers was tested on the epoc system to assess the concordance to reference ranges used locally. Results: Deming regression correlation coefficients for all the comparisons were above 0.65 except for ionized Ca2+. Accordance of greater than 85% to the local reference ranges were found in all assays with the exception of pO2 and Cl-. Conclusion: Data from this study indicates that capillary blood tests on the epoc system provide comparable results to reference method for these assays, Na+, K+, glucose, lactate, hematocrit, hemoglobin, pCO2, and pH. Further validation in critically ill patients is needed to implement the epoc system in patient transport. Impact of the study: This study demonstrated that capillary blood tests on the epoc Point of Care Blood Analysis System give comparable results to other chemistry analyzers for major blood gas and critical tests. The results are informative to institutions where pre-hospital and inter-hospital laboratory testing on capillary blood is a critical component of patient point of care testing. Keywords: Epoc, Capillary, Transport, Blood gas, Point of care

  11. Infraglottic lobular capillary hemangioma: A case report

    Directory of Open Access Journals (Sweden)

    Vinh Ly Pham Hoang

    2018-03-01

    Full Text Available Lobular capillary hemangioma (LCH is a benign proliferation of capillary blood vessels adopting a lobular configuration. A laryngeal origin of LCH is exceedingly rare. Here, we describe a case of an 11-year-old boy presenting with a subglottic lesion, leading to a subglottic stenosis. Histopathologic findings of the lesion implicated an LCH, which was removed successfully by a coblator. This is the first report of a subglottic LCH. Physicians should be aware of this unique lesion and laryngeal LCH should be considered in diagnosing the cause of a subglottic stenosis. Additionally, coblation should be an effective treatment for laryngeal LCH.

  12. Use of Plastic Capillaries for Macromolecular Crystallization

    Science.gov (United States)

    Potter, Rachel R.; Hong, Young-Soo; Ciszak, Ewa M.

    2003-01-01

    Methods of crystallization of biomolecules in plastic capillaries (Nalgene 870 PFA tubing) are presented. These crystallization methods used batch, free-interface liquid- liquid diffusion alone, or a combination with vapor diffusion. Results demonstrated growth of crystals of test proteins such as thaumatin and glucose isomerase, as well as protein studied in our laboratory such dihydrolipoamide dehydrogenase. Once the solutions were loaded in capillaries, they were stored in the tubes in frozen state at cryogenic temperatures until the desired time of activation of crystallization experiments.

  13. Capillary condensation of adsorbates in porous materials.

    Science.gov (United States)

    Horikawa, Toshihide; Do, D D; Nicholson, D

    2011-11-14

    Hysteresis in capillary condensation is important for the fundamental study and application of porous materials, and yet experiments on porous materials are sometimes difficult to interpret because of the many interactions and complex solid structures involved in the condensation and evaporation processes. Here we make an overview of the significant progress in understanding capillary condensation and hysteresis phenomena in mesopores that have followed from experiment and simulation applied to highly ordered mesoporous materials such as MCM-41 and SBA-15 over the last few decades. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Hysteretic capillary condensation in a porous material

    International Nuclear Information System (INIS)

    Lilly, M.P.; Hallock, R.B.

    1995-01-01

    The authors report on the behavior of hysteresis subloops in the capillary condensation of 4 He in the porous material Nuclepore. For hysteretic systems composed of many independent elements, the Preisach model may be used to predict the behavior of the resulting hysteresis. One prediction is that subloops with common chemical potential endpoints will be congruent. The observations of such subloops show that the prediction of congruence fails for this capillary condensation system. To understand deviations from Preisach behavior the authors modify the model to account for intersections among the pores. The modified model is in close agreement with the experimental results

  15. Intracerebral Capillary Hemangioma: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Youn, In Young; Kim, Jae Kyun; Byun, Jun Soo [Dept. of Radiology, Chung Ang University Medical Center, Chung Ang University College of Medicine, Seoul (Korea, Republic of); Park, Eon Sub [Dept. of Radiology, Chung Ang University Medical Center, Chung Ang University College of Medicine, Seoul (Korea, Republic of)

    2012-01-15

    Intracerebral capillary hemangiomas are very rare benign vascular tumors that mostly occur during infancy. We described a 69-year-old man with generalized tonic-clonic seizures who was diagnosed with an intracranial mass. Multidetector computed tomography, magnetic resonance imaging and digital subtraction angiography studies were performed for evaluation of brain, and there was a well-enhancing mass found in the right temporal lobe without a definite feeding vessel. The patient underwent surgery and the pathologic examination demonstrated marked proliferation of small vessels with a lobular pattern in the brain parenchyma, which was confirmed to be capillary hemangioma.

  16. Studies on pulsed hollow cathode capillary discharges

    Energy Technology Data Exchange (ETDEWEB)

    Choi, P; Dumitrescu-Zoita, C; Larour, J; Rous, J [Ecole Polytechnique, 91 - Palaiseau (France). Lab. de Physique des Milieux Ionises; Favre, M; Moreno, J; Chuaqui, H; Wyndham, E [Pontificia Univ. Catolica de Chile, Santiago (Chile). Facultad de Fisica; Zambra, M [Comision Chilena de Energia Nuclear, Santiago (Chile); Wong, C S [Univ. of Malaya, Kuala Lumpur (Malaysia). Plasma Research Lab

    1997-12-31

    Preliminary results on radiation characteristics of pulsed hollow cathode capillary discharges are presented. The device combines the on axis electron beam assisted ionization capabilities of the transient hollow cathode discharge with a novel high voltage low inductance geometrical design, which integrates the local energy storage into the electrode system. A nanosecond regime high temperature plasma is produced in a long, high aspect ratio capillary, with light emission in the UV to XUV region. The discharge is operated from near vacuum to pressure in the 1000 mTorr range. (author). 2 figs., 7 refs.

  17. TESTICULAR CAPILLARY HEMANGIOMA: DESCRIPTION OF A CASE

    Directory of Open Access Journals (Sweden)

    A. S. Markova

    2012-01-01

    Full Text Available The paper describes a clinical case of testicular capillary hemangioma in a 24-year-old man undergone a partial resection of the testis with the intraoperative morphological examination. Testicular capillary hemangioma is a rare benign tumor of a vascular origin, which can be similar to malignant testicular tumors on the clinical presentation, as well as on the imaging methods, in particular to seminoma. The intraoperative histological study can assist in avoiding organ-removing surgical interventions in diagnostically ambiguous cases if a benign testicular tumor is diagnosed.

  18. Two generalizations of column-convex polygons

    International Nuclear Information System (INIS)

    Feretic, Svjetlan; Guttmann, Anthony J

    2009-01-01

    Column-convex polygons were first counted by area several decades ago, and the result was found to be a simple, rational, generating function. In this work we generalize that result. Let a p-column polyomino be a polyomino whose columns can have 1, 2, ..., p connected components. Then column-convex polygons are equivalent to 1-convex polyominoes. The area generating function of even the simplest generalization, namely 2-column polyominoes, is unlikely to be solvable. We therefore define two classes of polyominoes which interpolate between column-convex polygons and 2-column polyominoes. We derive the area generating functions of those two classes, using extensions of existing algorithms. The growth constants of both classes are greater than the growth constant of column-convex polyominoes. Rather tight lower bounds on the growth constants complement a comprehensive asymptotic analysis.

  19. Leaching of glass

    International Nuclear Information System (INIS)

    Hench, L.L.

    1977-01-01

    Understanding surface compositional profiles of glasses over a range of 0-2000 A with a variety of analytical instruments shows that five general types of glass surfaces exist. The surface character of a glass article depends upon bulk composition and environmental history during which surface dealkalization, film formation, and network dissolution can occur. Environmental-surface interactions generally result in complex compositional profiles of all the constituents in a glass. Durable glasses almost always develop a stable surface film which has a higher concentration of network formers than the bulk composition. Compositional effects that are used to improve glass durability usually improve the stability of the surface films. Durability tests or service conditions that lead to film destruction are especially severe for the most silicate glasses. 43 references

  20. Quantification of nucleotides by ICPMS: coupling of ICPMS with capillary electrophoresis or capillary HPLC

    International Nuclear Information System (INIS)

    Inagaki, K.; Fujii, S.; Takatsu, A.; Yarita, T.; Zhu, Y.; Chiba, K.

    2009-01-01

    Full text: Quantification of nucleotides in small volumes of biological samples has eagerly been demanded. A method using ICPMS coupled with capillary electrophoresis or capillary liquid chromatography is reported. A new interface system, which consists of a double tube nebulizer inserted with a fused silica capillary tube and a cylinder mini-chamber with a sheath gas inlet, was designed. Moreover, the surface conditions of the sampling and skimmer cones, and the introduction of H 2 gas into the plasma were found to significantly improve the signal/background ratio for phosphorus determination at m/z 31. (author)

  1. Comprehensive protein profiling by multiplexed capillary zone electrophoresis using cross-linked polyacrylamide coated capillaries.

    Science.gov (United States)

    Liu, Shaorong; Gao, Lin; Pu, Qiaosheng; Lu, Joann J; Wang, Xingjia

    2006-02-01

    We have recently developed a new process to create cross-linked polyacrylamide (CPA) coatings on capillary walls to suppress protein-wall interactions. Here, we demonstrate CPA-coated capillaries for high-efficiency (>2 x 10(6) plates per meter) protein separations by capillary zone electrophoresis (CZE). Because CPA virtually eliminates electroosmotic flow, positive and negative proteins cannot be analyzed in a single run. A "one-sample-two-separation" approach is developed to achieve a comprehensive protein analysis. High throughput is achieved through a multiplexed CZE system.

  2. Hysteretic capillary condensation of 4He on Nuclepore substrates

    International Nuclear Information System (INIS)

    Godshalk, K.M.; Smith, D.T.; Hallock, R.B.

    1987-01-01

    Measurements of the approach to capillary condensation and the hysteresis encountered in capillary condensation are reported for helium adsorbed on the polycarbonate substrate Nuclepore. (Author) (5 refs., 3 figs.)

  3. Viscosity measurement in the capillary tube viscometer under unsteady flow

    International Nuclear Information System (INIS)

    Park, Heung Jun; Yoo, Sang Sin; Suh, Sang Ho

    2000-01-01

    The objective of the present study is to develop a new device that the viscous characteristics of fluids are determined by applying the unsteady flow concept to the traditional capillary tube viscometer. The capillary tube viscometer consists of a small cylindrical reservoir, capillary tube, a load cell system that measures the mass flow rate, interfaces, and computer. Due to the small size of the reservoir the height of liquid in the reservoir decreases as soon as the liquid in the reservoir drains out through the capillary and the mass flow rate in the capillary decreases as the hydrostatic pressure in the reservoir decreases resulting in a decrease of the shear rate in the capillary tube. The instantaneous shear rate and driving force in the capillary tube are determined by measuring the mass flow rate through the capillary, and the fluid viscosity is determined from the measured flow rate and the driving force

  4. 29 CFR 1926.755 - Column anchorage.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Column anchorage. 1926.755 Section 1926.755 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.755 Column anchorage. (a) General requirements for erection stability. (1) All columns shall be anchored by a minimum of 4 anchor...

  5. Adsorption columns for use in radioimmunoassays

    International Nuclear Information System (INIS)

    1976-01-01

    Adsorption columns are provided which can be utilized in radioimmunoassay systems such as those involving the separation of antibody-antigen complexes from free antigens. The preparation of the columns includes the treatment of retaining substrate material to render it hydrophilic, preparation and degassing of the separation material and loading the column

  6. Thermal process of an air column

    International Nuclear Information System (INIS)

    Lee, F.T.

    1994-01-01

    Thermal process of a hot air column is discussed based on laws of thermodynamics. The kinetic motion of the air mass in the column can be used as a power generator. Alternatively, the column can also function as a exhaust/cooler

  7. Evaluation of ODS-AQ stationary phase for use in capillary electrochromatography.

    Science.gov (United States)

    Djordjevic, N M; Fitzpatrick, F; Houdiere, F

    2001-04-01

    The aim of this study was to evaluate the applicability of ODS-AQ packing material as a stationary phase in capillary electrochromatography (CEC). The electroosmotic flow created on an ODS-AQ stationary phase was measured at different mobile phase compositions and at different column temperatures. It was observed that the electroosmotic flow generated in the column increased by 50% when the temperature of the system was raised from 20 degrees C to 60 degrees C, while all other conditions were kept constant. The electroosmotic flow produced by the ODS-AQ stationary phase was found to be comparable to the flow generated in a column packed with Nucleosil bare-silica material. In addition, a set of polar compounds (D-lysergic acid diethylamide derivatives) was utilized to determine the influence of temperature and mobile phase composition on their chromatographic behavior on an ODS-AQ stationary phase in a CEC mode. A linear relationship between the solute retention factor and column temperatures was seen over the temperature range studied (20 degrees C to 60 degrees C). A quadratic function was used to describe the changes in the solute retention factors with variation of acetonitrile concentration in the mobile phase.

  8. Tunable thick porous silica coating fabricated by multilayer-by-multilayer bonding of silica nanoparticles for open-tubular capillary chromatographic separation.

    Science.gov (United States)

    Qu, Qishu; Liu, Yuanyuan; Shi, Wenjun; Yan, Chao; Tang, Xiaoqing

    2015-06-19

    A simple coating procedure employing a multilayer-by-multilayer process to modify the inner surface of bare fused-silica capillaries with silica nanoparticles was established. The silica nanoparticles were adsorbed onto the capillary wall via a strong electrostatic interaction between amino functional groups and silica particles. The thickness of the coating could be tuned from 130 to 600 nm by increasing the coating cycles from one to three. Both the retention factor and the resolution were greatly increased with increasing coating cycles. The loading capacity determined by naphthalene in the column with three coating cycles is 152.1 pmol. The effects of buffer concentration and pH value on the stability of the coating were evaluated. The retention reproducibility of the separation of toluene was 0.8, 1.2, 2.3, and 4.5%, respectively, for run-to-run, day-to-day, column-to-column, and batch-to-batch, respectively. The chromatographic performance of these columns was evaluated by both capillary liquid chromatography and open-tubular capillary electrochromatography (OT-CEC). Separation of aromatic hydrocarbons in the column with three coating cycles provided high theoretical plate numbers (up to 269,280 plates m(-1) for toluene) and short separation time (<15 min) by using OT-CEC mode. The method was also used to separate egg white proteins. Both acidic and basic proteins as well as four glycoisoforms were separated in a single run. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Capillary-Patterns for Biometric Authentication

    NARCIS (Netherlands)

    Paloma Benedicto, J.; Bruekers, A.A.M.; Presura, C.N.; Garcia Molina, G.

    2007-01-01

    In this report, we present a method using the capillary structuresunder the "distal interphalangeal joint" (DIP joint), which is located between the second and third (distal) phalanges of the finger, for achieving secure biometric authentication. Images of the DIPjoint are acquired using a

  10. Capillary Condensation in Pores with Rough Walls:

    Czech Academy of Sciences Publication Activity Database

    Bryk, P.; Rżysko, W.; Malijevský, Alexandr; Sokołowski, S.

    2007-01-01

    Roč. 313, č. 1 (2007), s. 41-52 ISSN 0021-9797 Grant - others:TOK(XE) 509249 Institutional research plan: CEZ:AV0Z40720504 Source of funding: R - rámcový projekt EK Keywords : adsorption * pore * capillary condensation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.309, year: 2007

  11. Numerical simulations of capillary barrier field tests

    International Nuclear Information System (INIS)

    Morris, C.E.; Stormont, J.C.

    1997-01-01

    Numerical simulations of two capillary barrier systems tested in the field were conducted to determine if an unsaturated flow model could accurately represent the observed results. The field data was collected from two 7-m long, 1.2-m thick capillary barriers built on a 10% grade that were being tested to investigate their ability to laterally divert water downslope. One system had a homogeneous fine layer, while the fine soil of the second barrier was layered to increase its ability to laterally divert infiltrating moisture. The barriers were subjected first to constant infiltration while minimizing evaporative losses and then were exposed to ambient conditions. The continuous infiltration period of the field tests for the two barrier systems was modelled to determine the ability of an existing code to accurately represent capillary barrier behavior embodied in these two designs. Differences between the field test and the model data were found, but in general the simulations appeared to adequately reproduce the response of the test systems. Accounting for moisture retention hysteresis in the layered system will potentially lead to more accurate modelling results and is likely to be important when developing reasonable predictions of capillary barrier behavior

  12. Delayed Capillary Breakup of Falling Viscous Jets

    NARCIS (Netherlands)

    Javadi, A.; Eggers, J.; Bonn, D.; Habibi, M.; Ribe, N.M.

    2013-01-01

    Thin jets of viscous fluid like honey falling from capillary nozzles can attain lengths exceeding 10 m before breaking up into droplets via the Rayleigh-Plateau (surface tension) instability. Using a combination of laboratory experiments and WKB analysis of the growth of shape perturbations on a jet

  13. Imbibition of ``Open Capillary'': Fundamentals and Applications

    Science.gov (United States)

    Tani, Marie; Kawano, Ryuji; Kamiya, Koki; Okumura, Ko

    2015-11-01

    Control or transportation of small amount of liquid is one of the most important issues in various contexts including medical sciences or pharmaceutical industries to fuel delivery. We studied imbibition of ``open capillary'' both experimentally and theoretically, and found simple scaling laws for both statics and dynamics of the imbibition, similarly as that of imbibition of capillary tubes. Furthermore, we revealed the existence of ``precursor film,'' which developed ahead of the imbibing front, and the dynamics of it is described well by another scaling law for capillary rise in a corner. Then, to show capabilities of open capillaries, we demonstrated two experiments by fabricating micro mixing devices to achieve (1) simultaneous multi-color change of the Bromothymol blue (BTB) solution and (2) expression of the green florescent protein (GFP). This research was partly supported by ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan). M. T. is supported by the Japan Society for the Promotion of Science Research Fellowships for Young Scientists.

  14. Van de Graaff generator for capillary electrophoresis.

    Science.gov (United States)

    Lee, Seung Jae; Castro, Eric R; Guijt, Rosanne M; Tarn, Mark D; Manz, Andreas

    2017-09-29

    A new approach for high voltage capillary electrophoresis (CE) is proposed, which replaces the standard high voltage power supply with a Van de Graaff generator, a low current power source. Because the Van de Graaff generator is a current-limited source (10μA), potentials exceeding 100kV can be generated for CE when the electrical resistance of the capillary is maximized. This was achieved by decreasing the capillary diameter and reducing the buffer ionic strength. Using 2mM borate buffer and a 5μm i.d. capillary, fluorescently labeled amino acids were separated with efficiencies up to 3.5 million plates; a 5.7 fold improvement in separation efficiency compared to a normal power supply (NPS) typically used in CE. This separation efficiency was realized using a simple set-up without significant Joule heating, making the Van de Graaff generator a promising alternative for applying the high potentials required for enhancing resolution in the separation and analysis of highly complex samples, for example mixtures of glycans. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Capillary Electrophoresis Analysis of Conventional Splicing Assays

    DEFF Research Database (Denmark)

    de Garibay, Gorka Ruiz; Acedo, Alberto; García-Casado, Zaida

    2014-01-01

    of these assays is often challenging. Here, we explore this issue by conducting splicing assays in 31 BRCA2 genetic variants. All variants were assessed by RT-PCR followed by capillary electrophoresis and direct sequencing. If assays did not produce clear-cut outputs (Class-2 or Class-5 according to analytical...

  16. Application of CHESS single-bounce capillaries at synchrotron beamlines

    Science.gov (United States)

    Huang, R.; Szebenyi, T.; Pfeifer, M.; Woll, A.; Smilgies, D.-M.; Finkelstein, K.; Dale, D.; Wang, Y.; Vila-Comamala, J.; Gillilan, R.; Cook, M.; Bilderback, D. H.

    2014-03-01

    Single-bounce capillaries are achromatic X-ray focusing optics that can provide efficient and high demagnification focusing with large numerical apertures. Capillary fabrication at CHESS can be customized according to specific application requirements. Exemplary applications are reviewed in this paper, as well as recent progress on condensers for high-resolution transmission X-ray microscopy and small focal size capillaries.

  17. Using contemporary liquid chromatography theory and technology to improve capillary gradient ion-exchange separations.

    Science.gov (United States)

    Wouters, Bert; Broeckhoven, Ken; Wouters, Sam; Bruggink, Cees; Agroskin, Yury; Pohl, Christopher A; Eeltink, Sebastiaan

    2014-11-28

    The gradient-performance limits of capillary ion chromatography have been assessed at maximum system pressure (34.5 MPa) using capillary columns packed with 4.1 μm macroporous anion-exchange particles coated with 65 nm positively-charged nanobeads. In analogy to the van-Deemter curve, the gradient performance was assessed applying different flow rates, while decreasing the gradient time inversely proportional to the increase in flow rate in order to maintain the same retention properties. The gradient kinetic-performance limits were determined at maximum system pressure, applying tG/t0=5, 10, and 20. In addition, the effect of retention on peak width was assessed in gradient mode for mono-, di-, and trivalent inorganic anions. The peak width of late-eluting ions can be significantly reduced by using concave gradient, resulting in better detection sensitivity. A signal enhancement factor of 8 was measured for a late-eluting ion when applying a concave instead of a linear gradient. For the analysis of a complex anion mixture, a coupled column with a total length of 1.05 m was operated at the kinetic-performance limit applying a linear 250 min gradient (tG/t0=10). The peak capacity varied between 200 and 380 depending on analyte retention, and hence on charge and size of the ion. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Analysis of glycated hemoglobin A1c by capillary electrophoresis and capillary isoelectric focusing

    Czech Academy of Sciences Publication Activity Database

    Koval, Dušan; Kašička, Václav; Cottet, H.

    2011-01-01

    Roč. 413, č. 1 (2011), s. 8-15 ISSN 0003-2697 R&D Projects: GA ČR GP203/09/P485; GA ČR(CZ) GA203/08/1428 Institutional research plan: CEZ:AV0Z40550506 Keywords : capillary zone electrophoresis * capillary isoelectric focusing * glycated hemoglobin HbA1c Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.996, year: 2011

  19. Validation of capillary blood analysis and capillary testing mode on the epoc Point of Care system.

    Science.gov (United States)

    Cao, Jing; Edwards, Rachel; Chairez, Janette; Devaraj, Sridevi

    2017-12-01

    Laboratory test in transport is a critical component of patient care, and capillary blood is a preferred sample type particularly in children. This study evaluated the performance of capillary blood testing on the epoc Point of Care Blood Analysis System (Alere Inc). Ten fresh venous blood samples was tested on the epoc system under the capillary mode. Correlation with GEM 4000 (Instrumentation Laboratory) was examined for Na+, K+, Cl-, Ca2+, glucose, lactate, hematocrit, hemoglobin, pO2, pCO2, and pH, and correlation with serum tested on Vitros 5600 (Ortho Clinical Diagnostics) was examined for creatinine. Eight paired capillary and venous blood was tested on epoc and ABL800 (Radiometer) for the correlation of Na+, K+, Cl-, Ca2+, glucose, lactate, hematocrit, hemoglobin, pCO2, and pH. Capillary blood from 23 apparently healthy volunteers was tested on the epoc system to assess the concordance to reference ranges used locally. Deming regression correlation coefficients for all the comparisons were above 0.65 except for ionized Ca2+. Accordance of greater than 85% to the local reference ranges were found in all assays with the exception of pO2 and Cl-. Data from this study indicates that capillary blood tests on the epoc system provide comparable results to reference method for these assays, Na+, K+, glucose, lactate, hematocrit, hemoglobin, pCO2, and pH. Further validation in critically ill patients is needed to implement the epoc system in patient transport. This study demonstrated that capillary blood tests on the epoc Point of Care Blood Analysis System give comparable results to other chemistry analyzers for major blood gas and critical tests. The results are informative to institutions where pre-hospital and inter-hospital laboratory testing on capillary blood is a critical component of patient point of care testing.

  20. A capillary pumping device utilizing super-hydrophobic silicon grass

    International Nuclear Information System (INIS)

    Kung, Chun-Fei; Chang, Chien-Cheng; Chu, Chin-Chou

    2011-01-01

    In this study, we show that a compact silicon grass surface can be generated by utilizing the induced coupled plasma method with suitably chosen fabrication parameters. This super-hydrophobic structure suspends deionized water on top of the grass and keeps the contact angle at around 153°. The silicon grass is used to improve the driving efficiency of a capillary pumping micro-duct (without sidewalls), which is completely defined by a bottom hydrophilic stripe (adjacent to a Teflon substrate) and a fully top-covered hydrophobic Teflon surface which is coated on a glass substrate. The channel has a height of 3 µm and a width of 100 µm. In this work, the Teflon substrate is replaced with the silicon grass surface. When the fluid is flowing through the micro-duct on the stripe, the interface between the silicon grass and the hydrophilic stripe forms a stable air cushion barrier to the fluid, thus effectively reducing the frictional force. By changing only the interface with this replacement, we demonstrate that the average measured velocities of the new design show improvements of 21% and 17% in the driving efficiency over the original design for transporting deionized water and human blood, respectively. It is also shown that the measured data of the present design are closer to the values predicted by a theoretical analysis which relates the flow velocity to the contact angles, surface tension and fluid viscosity

  1. Cytologic examination of hemorrhagic fluid by capillary centrifugation: a new technique.

    Science.gov (United States)

    Agarwal, Padam Kumari

    2009-01-01

    To develop a simplified technique for processing hemorrhagic body fluids, allowing elimination of red blood cells (RBCs) to obtain tumor cell-rich cytosmears for accurate diagnosis of malignancy. Hemorrhagic fluid is collected with ethylenediamine tetraacetic acid anticoagulant. The cells are separated by centrifugation in glass capillaries into 3 layers, with the uppermost containing supernatant, middle buffy coat and lowermost dark layer of RBCs. The smears of the buffy coat are prepared by breaking the capillaries at the junction of buffy coat and RBC layer. The procedure is named capillary centrifugation technique. This procedure was developed in the cytology laboratory at King George's Medical College, Lucknow, India in 1974. Cell yield is good and cellular details are well preserved. No cell debris is present on the slides. The background of the smears is absolutely clear. Any number of slides may be prepared for special study for exact typing of tumor cells This is a simple, economical procedure and a good substitute for a cytocentrifuge machine for preparing smears from small amount of fluids. Technicians learn it quickly and are quite comfortable with the procedure.

  2. Ellipsoidal capillary as condenser for the BESSY full-field x-ray microscope

    International Nuclear Information System (INIS)

    Guttmann, P; Heim, S; Schneider, G; Zeng, X; Feser, M; Yun, W

    2009-01-01

    The BESSY x-ray microscopy group has developed a new full-field x-ray microscope which employs an advanced x-ray optical concept. Traditionally, zone plate based condensers are used in x-ray microscopes providing an energy resolution of only E/ΔE ≤ 500. In addition, this conventional monochromator concept requires a pinhole close to the sample restricting the available space for tomography applications. In our new BESSY microscope, a standard monochromator beam line provides a high energy resolution of up to 10,000 which permits NEXAFS studies. An elliptically shaped mono-capillary is used to form the hollow cone illumination necessary for sample illumination and to match the aperture of the objective. Calculations regarding the performance and accuracies needed are presented and characterizations of capillaries especially made for the BESSY soft x-ray microscope are shown. For the first time, we demonstrate that glass capillaries are well suited as condensers in the soft x-ray energy domain. Their focusing efficiency was measured to be 80% which is about an order of magnitude higher than the diffraction efficiency of zone plate based condensers.

  3. High-resolution tracking using large capillary bundles filled with liquid scintillator

    CERN Document Server

    Annis, P; Benussi, L; Bruski, N; Buontempo, S; Currat, C; D'Ambrosio, N; Van Dantzig, R; Dupraz, J P; Ereditato, A; Fabre, Jean-Paul; Fanti, V; Feyt, J; Frekers, D; Frenkel, A; Galeazzi, F; Garufi, F; Goldberg, J; Golovkin, S V; Gorin, A M; Grégoire, G; Harrison, K; Höpfner, K; Holtz, K; Konijn, J; Kozarenko, E N; Kreslo, I E; Kushnirenko, A E; Liberti, B; Martellotti, G; Medvedkov, A M; Michel, L; Migliozzi, P; Mommaert, C; Mondardini, M R; Panman, J; Penso, G; Petukhov, Yu P; Rondeshagen, D; Siegmund, W P; Tyukov, V E; Van Beek, G; Vasilchenko, V G; Vilain, P; Visschers, J L; Wilquet, G; Winter, Klaus; Wolff, T; Wörtche, H J; Wong, H; Zimyn, K V

    2000-01-01

    We have developed large high-resolution tracking detectors based on glass capillaries filled with organic liquid scintillator of high refractive index. These liquid-core scintillating optical fibres act simultaneously as detectors of charged particles and as image guides. Track images projected onto the readout end of a capillary bundle are visualized by an optoelectronic chain consisting of a set of image-intensifier tubes followed by a photosensitive CCD or by an EBCCD camera. Two prototype detectors, each composed of \\hbox{$\\approx 10^6$} capillaries with \\hbox{20$-$25 $\\mu$m} diameter and \\hbox{0.9$-$1.8 m} length, have been tested, and a spatial resolution of the order of \\hbox{20$-$40 $\\mu$m} has been attained. A high scintillation efficiency and a large light-attenuation length, in excess of 3 m, was achieved through special purification of the liquid scintillator. Along the tracks of minimum-ionizing particles, the hit densities obtained were $\\sim$ 8 hits/mm at the readout window, and \\hbox{$\\sim$ 3 ...

  4. Simple, specific analysis of organophosphorus and carbamate pesticides in sediments using column extraction and gas chromatography

    Science.gov (United States)

    Belisle, A.A.; Swineford, D.M.

    1988-01-01

    A simple, specific procedure was developed for the analysis of organophosphorus and carbamate pesticides in sediment. The wet soil was mixed with anhydrous sodium sulfate to bind water and the residues were column extracted in acetone:methylene chloride (1:l,v/v). Coextracted water was removed by additional sodium sulfate packed below the sample mixture. The eluate was concentrated and analyzed directly by capillary gas chromatography using phosphorus and nitrogen specific detectors. Recoveries averaged 93 % for sediments extracted shortly after spiking, but decreased significantly as the samples aged.

  5. Correlation to predict heat transfer of an oscillating loop heat pipe consisting of three interconnected columns

    International Nuclear Information System (INIS)

    Arslan, Goekhan; Ozdemir, Mustafa

    2008-01-01

    In this paper, heat transfer in an oscillating loop heat pipe is investigated experimentally. The oscillation of the liquid columns at the evaporator and condenser sections of the heat pipe are driven by gravitational force and the phase lag between evaporation and condensation because the dimensions of the heat pipe are large enough to neglect the effect of capillary forces. The overall heat transfer coefficient based on the temperature difference between the evaporator and condenser surfaces is introduced by a correlation function of dimensionless numbers such as kinetic Reynolds number, c p ΔT/h fg and the geometric parameters

  6. A complete soil hydraulic model accounting for capillary and adsorptive water retention, capillary and film conductivity, and hysteresis

    NARCIS (Netherlands)

    Sakai, Masaru; Van Genuchten, Martinus Th|info:eu-repo/dai/nl/31481518X; Alazba, A. A.; Setiawan, Budi Indra; Minasny, Budiman

    2015-01-01

    A soil hydraulic model that considers capillary hysteretic and adsorptive water retention as well as capillary and film conductivity covering the complete soil moisture range is presented. The model was obtained by incorporating the capillary hysteresis model of Parker and Lenhard into the hydraulic

  7. Fractography of glass

    CERN Document Server

    Tressler, Richard

    1994-01-01

    As the first major reference on glass fractography, contributors to this volume offer a comprehensive account of the fracture of glass as well as various fracture surface topography Contributors discuss optical fibers, glass containers, and flatglass fractography In addition, papers explore fracture origins; the growth of the original flaws of defects; and macroscopic fracture patterns from which fracture patterns evolve This volume is complete with photographs and schematics

  8. Diamond turning of glass

    Energy Technology Data Exchange (ETDEWEB)

    Blackley, W.S.; Scattergood, R.O.

    1988-12-01

    A new research initiative will be undertaken to investigate the critical cutting depth concepts for single point diamond turning of brittle, amorphous materials. Inorganic glasses and a brittle, thermoset polymer (organic glass) are the principal candidate materials. Interrupted cutting tests similar to those done in earlier research are Ge and Si crystals will be made to obtain critical depth values as a function of machining parameters. The results will provide systematic data with which to assess machining performance on glasses and amorphous materials

  9. Glass to contain wastes

    International Nuclear Information System (INIS)

    Moncouyoux, M.; Jacquet-Francillon, M.

    1994-01-01

    Here are the tables and figures presented during the conference on the glass to confine high level radioactive wastes: definition, fabrication, storage and disposal. The composition of glasses are detailed, their properties and the vitrification proceeding. The behaviour of these glasses in front of water, irradiation and heat are shown. The characteristics of parcels are given according to the radiation protection rule, ALARA principle, the concept of multi-barriers and the geological stability

  10. Glass microspheres for brachytherapy

    International Nuclear Information System (INIS)

    Prado, Miguel O.; Prastalo, Simon; Blaumann, Herman; Longhino, Juan M.; Repetto Llamazares, A.H.V.

    2007-01-01

    We developed the capacity to produce glass microspheres containing in their structure one or more radioactive isotopes useful for brachytherapy. We studied the various facts related with their production: (Rare earth) alumino silicate glass making, glass characterization, microspheres production, nuclear activation through (n,γ) nuclear reactions, mechanical characterization before and after irradiation. Corrosion tests in simulated human plasma and mechanical properties characterization were done before and after irradiation. (author) [es

  11. Silicate glasses. Chapter 1

    International Nuclear Information System (INIS)

    Lutze, W.

    1988-01-01

    This chapter is a survey of world-wide research and development efforts in nuclear waste glasses and its production technology. The principal glasses considered are silicate glasses which contain boron, i.e. borosilicate glass. A historical overview of waste form development programs in nine countries is followed by a summary of the design criteria for borosilicate glass compositions glass compositions. In the sections on glass properties the waste form is characterized in terms of potential alterations under the influence of heat, thermal gradients, radiation, aqueous solutions and combinations thereof. The topics are phase transformations, mechanical properties, radiation effects and chemical durability. The results from studies of volcanic glasses, as natural analogues for borosilicate nuclear waste glasses in order to verify predictions obtained from short-term tests in the laboratory, have been compiled in a special section on natural analogues. A special section on advanced vitrification techniques summarizes the various actual and potential processing schemes and describes the facilities. The literature has been considered until 1985. (author). 430 refs.; 68 figs.; 29 tabs

  12. Glass and vitrification

    International Nuclear Information System (INIS)

    Barton, J.L.; Vacher, R.; Moncouyoux, J.P.; Vernaz, E.

    1997-01-01

    Most glasses used as materials are oxides glasses that are produced by a quick quench of a liquid. Glasses are characterized by the absence of periodicity in the atomic arrangements, they do not have symmetries and do not present order over a long distance. This series of 4 short articles present: 1) the properties of glass and its industrial story, 2) the glass structure, 3) a forty years long story of glass as dies used to confine wastes and 4) the methodology used to study the behaviour of glass over very long periods of time. This methodology is based on 5 steps: 1) define and specify the material to study (the prediction of long term alteration of a material is nonsense unless you know well its initial properties), 2) identify all the alteration processes that are likely to happen, determine their kinetics and the influence of environmental parameters, 3) develop mathematical models in order to simulate long-term behaviour of glasses, 4) determine the release rates of the radionuclides confined in the glass, and 5) validate data and models, it is not possible to expect a complete validation of a model that will be extrapolated over tens of thousands of years, nevertheless some ways of validation can lead to a satisfactory level of confidence taking into account reasonable uncertainties. (A.C.)

  13. Early capillary flux homogenization in response to neural activation.

    Science.gov (United States)

    Lee, Jonghwan; Wu, Weicheng; Boas, David A

    2016-02-01

    This Brief Communication reports early homogenization of capillary network flow during somatosensory activation in the rat cerebral cortex. We used optical coherence tomography and statistical intensity variation analysis for tracing changes in the red blood cell flux over hundreds of capillaries nearly at the same time with 1-s resolution. We observed that while the mean capillary flux exhibited a typical increase during activation, the standard deviation of the capillary flux exhibited an early decrease that happened before the mean flux increase. This network-level data is consistent with the theoretical hypothesis that capillary flow homogenizes during activation to improve oxygen delivery. © The Author(s) 2015.

  14. Characterization of glass and glass ceramic nuclear waste forms

    International Nuclear Information System (INIS)

    Lutze, W.; Borchardt, J.; De, A.K.

    1979-01-01

    Characteristics of solidified nuclear waste forms, glass and glass ceramic compositions and the properties (composition, thermal stability, crystallization, phase behavior, chemical stability, mechanical stability, and radiation effects) of glasses and glass ceramics are discussed. The preparation of glass ceramics may be an optional step for proposed vitrification plants if tailored glasses are used. Glass ceramics exhibit some improved properties with respect to glasses. The overall leach resistance is similar to that of glasses. An increased leach resistance may become effective for single radionuclides being hosted in highly insoluble crystal phases mainly when higher melting temperatures are applicable in order to get more leach resistant residual glass phases. The development of glass ceramic is going on. The technological feasibility is still to be demonstrated. The potential gain of stability when using glass ceramics qualifies the material as an alternative nuclear waste form

  15. Design of Capillary Flows with Spatially Graded Porous Films

    Science.gov (United States)

    Joung, Young Soo; Figliuzzi, Bruno Michel; Buie, Cullen

    2013-11-01

    We have developed a new capillary tube model, consisting of multi-layered capillary tubes oriented in the direction of flow, to predict capillary speeds on spatially graded porous films. Capillary flows through thin porous media have been widely utilized for small size liquid transport systems. However, for most media it is challenging to realize arbitrary shapes and spatially functionalized micro-structures with variable flow properties. Therefore, conventional media can only be used for capillary flows obeying Washburn's equation and the modifications thereof. Given this background, we recently developed a method called breakdown anodization (BDA) to produce highly wetting porous films. The resulting surfaces show nearly zero contact angles and fast water spreading speed. Furthermore, capillary pressure and spreading diffusivity can be expressed as functions of capillary height when customized electric fields are used in BDA. From the capillary tube model, we derived a general capillary flow equation of motion in terms of capillary pressure and spreading diffusivity. The theoretical model shows good agreement with experimental capillary flows. The study will provide novel design methodologies for paper-based microfluidic devices.

  16. Capillary Interactions between a Probe Tip and a Nanoparticle

    International Nuclear Information System (INIS)

    Li-Ning, Sun; Le-Feng, Wang; Wei-Bin, Rong

    2008-01-01

    To understand capillary interactions between probe tips and nanoparticles under ambient conditions, a theoretical model of capillary forces between them is developed based on the geometric relations. It is found that the contribution of surface tension force to the total capillary force attains to similar order of magnitude as the capillary pressure force in many cases. It is also shown that the tip shape and the radial distance of the meniscus have great influence on the capillary force. The capillary force decreases with the increasing separation distances, and the variance of the contact angles may change the magnitudes of capillary forces several times at large radial distances. The applicability of the symmetric meniscus approximation is discussed. (condensed matter: structure, mechanical and thermal properties)

  17. Investigation of the output pulse characteristics of a 46.9 nm Ar capillary discharge soft x-ray laser

    International Nuclear Information System (INIS)

    Ritucci, A.; Tomassetti, G.; Palladino, L.; Reale, A.; Gaeta, G.; Limongi, T.; Flora, F.; Mezi, L.; Kukhlevsky, S.V.; Kaiser, J.; Faenov, A.; Pikuz, T.; Reale, L.

    2002-01-01

    In this paper, we report on the realization of a capillary discharge soft x-ray laser operating at 46.9 nm pumped by a 30 kA peak value, 150 ns half cycle duration current pulse (corresponding to a mean current slope of about 5 1011 A/s). The slope of the pumping current is sufficiently high to produce the plasma compression and laser amplification on the 3p-3s, J=0-1 transition of Ne-like Ar, in 2.4-4 mm in diameter alumina capillary channels. We have analyzed the output pulse characteristics of the produced laser beam, such as the lasing time and the pulse duration, the saturation and the output pulse energy, the near field image as a function of different experimental parameters. Using the same current pulse, the lasing effect has not been observed in polyacetal capillaries, demonstrating the damning role of the wall capillary ablation in the heating and in the stability of the plasma column during the z-pinch compression

  18. Improved Peak Capacity for Capillary Electrophoretic Separations of Enzyme Inhibitors with Activity-Based Detection Using Magnetic Bead Microreactors

    Science.gov (United States)

    Yan, Xiaoyan; Gilman, S. Douglass

    2010-01-01

    A technique for separating and detecting enzyme inhibitors was developed using capillary electrophoresis with an enzyme microreactor. The on-column enzyme microreactor was constructed using NdFeB magnet(s) to immobilize alkaline phosphatase-coated superparamagnetic beads (2.8 μm diameter) inside a capillary before the detection window. Enzyme inhibition assays were performed by injecting a plug of inhibitor into a capillary filled with the substrate, AttoPhos. Product generated in the enzyme microreactor was detected by laser-induced fluorescence. Inhibitor zones electrophoresed through the capillary, passed through the enzyme microreactor, and were observed as negative peaks due to decreased product formation. The goal of this study was to improve peak capacities for inhibitor separations relative to previous work, which combined continuous engagement electrophoretically mediated microanalysis (EMMA) and transient engagement EMMA to study enzyme inhibition. The effects of electric field strength, bead injection time and inhibitor concentrations on peak capacity and peak width were investigated. Peak capacities were increased to ≥20 under optimal conditions of electric field strength and bead injection time for inhibition assays with arsenate and theophylline. Five reversible inhibitors of alkaline phosphatase (theophylline, vanadate, arsenate, L-tryptophan and tungstate) were separated and detected to demonstrate the ability of this technique to analyze complex inhibitor mixtures. PMID:20024913

  19. Oscillating water column structural model

    Energy Technology Data Exchange (ETDEWEB)

    Copeland, Guild [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bull, Diana L [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jepsen, Richard Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gordon, Margaret Ellen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    An oscillating water column (OWC) wave energy converter is a structure with an opening to the ocean below the free surface, i.e. a structure with a moonpool. Two structural models for a non-axisymmetric terminator design OWC, the Backward Bent Duct Buoy (BBDB) are discussed in this report. The results of this structural model design study are intended to inform experiments and modeling underway in support of the U.S. Department of Energy (DOE) initiated Reference Model Project (RMP). A detailed design developed by Re Vision Consulting used stiffeners and girders to stabilize the structure against the hydrostatic loads experienced by a BBDB device. Additional support plates were added to this structure to account for loads arising from the mooring line attachment points. A simplified structure was designed in a modular fashion. This simplified design allows easy alterations to the buoyancy chambers and uncomplicated analysis of resulting changes in buoyancy.

  20. Controllable preparation of copper phthalocyanine single crystal nano column and its chlorine gas sensing properties

    Directory of Open Access Journals (Sweden)

    Jianhong Zhao

    2016-09-01

    Full Text Available The unsubstituted copper phthalocyanine (CuPc single crystal nano columns were fabricated for the first time as chlorine (Cl2 gas sensors in this paper. The nano columns of CuPc have been prepared on different substrates via template-free physical vapor deposition (PVD approach. The growth mechanism of CuPc nano column on quartz was explored and the same condition used on other substrates including glass, sapphire (C-plane, M-plane, R-plane, Si and SiO2/Si came to a same conclusion, which confirmed that the aligned growth of CuPc nano column is not substrate-dependent. And then the CuPc nano column with special morphology was integrated as in-situ sensor device which exhibits high sensitivity and selectivity towards Cl2 at room temperature with a minimum detection limit as low as 0.08 ppm. The response of sensor was found to increase linearly (26∼659% with the increase for Cl2 within concentration range (0.08∼4.0ppm. These results clearly demonstrate the great potential of the nano column growth and device integration approach for sensor device.

  1. Relaxations in spin glasses: Similarities and differences from ordinary glasses

    International Nuclear Information System (INIS)

    Ngai, K.L.; Rajagopal, A.K.; Huang, C.Y.

    1984-01-01

    Relaxation phenomena have become a major concern in the physics of spin glasses. There are certain resemblances of these relaxation properties to those of ordinary glasses. In this work, we compare the relaxation properties of spin glasses near the freezing temperature with those of glasses near the glass transition temperature. There are similarities between the two types of glasses. Moreover, the relaxation properties of many glasses and spin glasses are in conformity with two coupled ''universality'' relations predicted by a recent model of relaxations in condensed matter

  2. Evaluation of Structural Cellular Glass

    Science.gov (United States)

    Adams, M. A.; Zwissler, J. G.

    1984-01-01

    Preliminary design information presented. First report discusses state of structural-cellular-glass programs as of June 1979. Second report gives further details of program to develop improved cellular glasses and to characterize properties of glasses and commercially available materials.

  3. Electric glass capturing markets

    Energy Technology Data Exchange (ETDEWEB)

    Wikman, K.; Wikstroem, T.

    1996-11-01

    Electric glass has found its place on the construction market. In public buildings, electrically heatable windows are becoming the leading option for large glass walls. Studies on detached houses, both new and renovated, show that floor heating combined with electrically heatable windowpanes is the best choice with respect to resident`s comfort. (orig.)

  4. Radioresistance of inorganic glasses

    International Nuclear Information System (INIS)

    Vorob'ev, A.A.; Zavadovskaya, E.K.; Fedorov, B.V.; Starodubtsev, V.A.

    1977-01-01

    Regularities are considered in the variation of properties of glass due to irradiations. On the basis of previous theoretical statements and experimental investigations, it is inferred that the irradiation resistance of glasses of the same type, synthesis conditions, content of impurities and amount of imperfections, is a function of the ''element-oxygen'' bond energy. The irradiation resistance depends on the number and the nature of glass structure imperfections. The averaged level of bonding forces is indicative of the glass formation temperature; the imperfections in glasses are formed in structure elements whose amount predominates as compared to the others. Electric charges which accumulate on the crack surface tend to increase its size, thus lessening even further the electric strength of the dielectric. The greater the irradiation time, the greater the number of irradiation imperfections causing a drop in the electric strength of glass. When choosing a glass for service in a radiation field, it is necessary to select those of a highest temperature of glass formation and with a least amount of imperfections

  5. Nucleation in ZBLAN glasses

    NARCIS (Netherlands)

    de Leede, G.L.A.; Waal, de H.

    1989-01-01

    Nucleation rates were detd. in a ZrF4-BaF2-NaF-LaF3-AlF3 glass (ZBLAN) using an optical method. The results were compared with a similar glass having a slightly different compn. The difference in the nucleation rate is explained by classical nucleation theory using calcd. free-energy differences

  6. Reliable and Accurate Release of Micro-Sized Objects with a Gripper that Uses the Capillary-Force Method

    Directory of Open Access Journals (Sweden)

    Suzana Uran

    2017-06-01

    Full Text Available There have been recent developments in grippers that are based on capillary force and condensed water droplets. These are used for manipulating micro-sized objects. Recently, one-finger grippers have been produced that are able to reliably grip using the capillary force. To release objects, either the van der Waals, gravitational or inertial-forces method is used. This article presents methods for reliably gripping and releasing micro-objects using the capillary force. The moisture from the surrounding air is condensed into a thin layer of water on the contact surfaces of the objects. From the thin layer of water, a water meniscus between the micro-sized object, the gripper and the releasing surface is created. Consequently, the water meniscus between the object and the releasing surface produces a high enough capillary force to release the micro-sized object from the tip of the one-finger gripper. In this case, either polystyrene, glass beads with diameters between 5–60 µm, or irregularly shaped dust particles of similar sizes were used. 3D structures made up of micro-sized objects could be constructed using this method. This method is reliable for releasing during assembly and also for gripping, when the objects are removed from the top of the 3D structure—the so-called “disassembling gripping” process. The accuracy of the release was lower than 0.5 µm.

  7. Determination of parabens in sweeteners by capillary electrochromatography

    Directory of Open Access Journals (Sweden)

    Carla Beatriz Grespan Bottoli

    2011-12-01

    Full Text Available Parabens, common food preservatives, were analysed by capillary electrochromatography, using a commercial C18 silica (3 µm, 40 cm × 100 µm i. d. capillary column as separation phase. In order to optimise the separation of these preservatives, the effects of mobile phase composition on the separation were evaluated, as well as the applied voltage and injection conditions. The retention behavior of these analytes was strongly influenced by the level of acetonitrile in the mobile phase. An optimal separation of the parabens was obtained within 18.5 minutes with a pH 8.0 mobile phase composed of 50:50 v/v tris(hydroxymethylaminomethane buffer and acetonitrile. The method was successfully applied to the quantitative analysis of paraben preservatives in sweetener samples with direct injection.Os parabenos, empregados como conservantes em alimentos, foram analisados por eletrocromatografia capilar, empregando uma coluna comercial recheada com partículas de sílica-C18 (3 µm, 40 cm × 100 µm d. i. como fase estacionária de separação. Para otimizar a separação destes conservantes foram avaliados os efeitos da composição da fase móvel na separação, bem como a voltagem e as condições de injeção. O comportamento de retenção dos analitos foi fortemente influenciado pela proporção de acetonitrila na fase móvel. A separação dos parabenos foi alcançada em 18,5 min com uma fase móvel contendo tampão tris(hidroximetilaminometano e acetonitrila na proporção 50:50 v/v. O método foi aplicado na análise quantitativa de parabenos em adoçantes empregando a injeção direta das amostras.

  8. Microfluidic chip-capillary electrophoresis devices

    CERN Document Server

    Fung, Ying Sing; Du, Fuying; Guo, Wenpeng; Ma, Tongmei; Nie, Zhou; Sun, Hui; Wu, Ruige; Zhao, Wenfeng

    2015-01-01

    Capillary electrophoresis (CE) and microfluidic chip (MC) devices are relatively mature technologies, but this book demonstrates how they can be integrated into a single, revolutionary device that can provide on-site analysis of samples when laboratory services are unavailable. By introducing the combination of CE and MC technology, Microfluidic Chip-Capillary Electrophoresis Devices broadens the scope of chemical analysis, particularly in the biomedical, food, and environmental sciences. The book gives an overview of the development of MC and CE technology as well as technology that now allows for the fabrication of MC-CE devices. It describes the operating principles that make integration possible and illustrates some achievements already made by the application of MC-CE devices in hospitals, clinics, food safety, and environmental research. The authors envision further applications for private and public use once the proof-of-concept stage has been passed and obstacles to increased commercialization are ad...

  9. Mechanical relaxation in glasses

    International Nuclear Information System (INIS)

    Hiki, Y.

    2004-01-01

    The basic properties of glasses and the characteristics of mechanical relaxation in glasses were briefly reviewed, and then our studies concerned were presented. Experimental methods adopted were viscosity, internal friction, ultrasonic attenuation, and Brillouin scattering measurements. The specimens used were several kinds of inorganic, organic, and metallic glasses. The measurements were mainly carried out from the room temperature up to the glass transition temperature, and the relaxation time was determined as a function of temperature. The 'double relaxation' composed of two Arrhenius-type relaxations was observed in many materials. In both relaxations, the 'compensation effect' showing a correlation of the pre-exponential factor and the activation energy was observed. These results were explained by considering the 'complex relaxation' due to cooperative motions of atoms or group of atoms. Values of activation energy near the glass transition determined by the various experimental methods were compared with each other

  10. Polymorphism in glasses

    International Nuclear Information System (INIS)

    Landa, L.M.; Nikolaeva, I.N.

    1979-01-01

    To defect phase interfaces and spasmodic properties change, the inhomogeneity and the second radiation effects in quartz glass, metamict phase and intermediate states have been investigated. When irradiating with fast neutrons the transformation of quartz glass - metamict phase occurs completely. The transformation is completed at 2x10 20 part./cm 2 dose. Thermal treatment not only increases the number of inhomogeneities but also results in increasing quartz glass density. Annealing transforms the metamict phase into common quartz glass at 1400 K. The fact, that thermal treatment results in the complete transformation of metamict phase into quartz glass, and the inverse transformation occurs only partially, is quite regular, as the metamict phase has a lesser entropy and is a more ordered state. It is shown that different amorphous phases of a chemical composition have different structures and properties, that there are interfaces between them, and the transformation from one state to another in microvolumes is realized spasmodically and requires expenditure of energy

  11. Demonstration of Nautilus Centripetal Capillary Condenser Technology

    Science.gov (United States)

    Wheeler, RIchard; Tang, Linh; Wambolt, Spencer; Golliher, Eric; Agui, Juan

    2016-01-01

    This paper describes the results of a proof of concept effort for development of a Nautilus Centripetal Capillary Condenser (NCCC or NC3) used for microgravity compatible water recovery from moist air with integral passive phase separation. Removal of liquid condensate from the air stream exiting a condenser is readily performed here on Earth. In order to perform this function in space however, without gravity or mechanical action, other tactics including utilization of inertial, drag and capillary forces are required. Within the NC3, liquid water forms via condensation on cold condenser surfaces as humid air passes along multiple spiral channels, each in its own plane, all together forming a stacked plate assembly. Non-mechanical inertial forces are employed to transfer condensate, as it forms, via centripetal action to the outer perimeter of each channel. A V-shaped groove, constructed on this outer edge of the spiral channel, increases local capillary forces thereby retaining the liquid. Air drag then pulls the liquid along to a collection region near the center of the device. Dry air produced by each parallel spiral channel is combined in a common orthogonal, out-of-plane conduit passing down the axial center of the stacked device. Similarly, the parallel condensate streams are combined and removed from the condenser/separator through yet another out-of-plane axial conduit. NC3 is an integration of conventional finned condenser operation, combined with static phase separation and capillary transport phenomena. A Mars' transit mission would be a logical application for this technology where gravity is absent and the use of vibrating, energy-intensive, motor-driven centrifugal separators is undesired. Here a vapor stream from either the Heat Melt Compactor or the Carbon dioxide Reduction Assembly, for example, would be dried to a dew point of 10 deg using a passive NC3 condenser/separator with the precious water condensate recycled to the water bus.

  12. Liquid-chromatographic analysis for cyclosporine with use of a microbore column and small sample volume.

    Science.gov (United States)

    Annesley, T; Matz, K; Balogh, L; Clayton, L; Giacherio, D

    1986-07-01

    This liquid-chromatographic assay requires 0.2 to 0.5 mL of whole blood, avoids the use of diethyl ether, and consumes only 10 to 20% of the solvents used in prior methods. Sample preparation involves an acidic extraction with methyl-t-butyl ether, performed in a 13 X 100 mm disposable glass tube, then a short second extraction of the organic phase with sodium hydroxide. After evaporation of the methyl-t-butyl ether, chromatography is performed on an "Astec" 2.0-mm (i.d.) octyl column. We compared results by this procedure with those by use of earlier larger-scale extractions and their respective 4.6-mm (i.d.) columns; analytical recoveries of cyclosporins A and D were comparable with previous findings and results for patients' specimens were equivalent, but the microbore columns provided greatly increased resolution and sensitivity.

  13. The order of condensation in capillary grooves

    International Nuclear Information System (INIS)

    Rascón, Carlos; Parry, Andrew O; Nürnberg, Robert; Pozzato, Alessandro; Tormen, Massimo; Bruschi, Lorenzo; Mistura, Giampaolo

    2013-01-01

    We consider capillary condensation in a deep groove of width L. The transition occurs at a pressure p co (L) described, for large widths, by the Kelvin equation p sat − p co (L) = 2σcosθ/L, where θ is the contact angle at the side walls and σ is the surface tension. The order of the transition is determined by the contact angle of the capped end θ cap ; it is continuous if the liquid completely wets the cap, and first-order otherwise. When the transition is first-order, corner menisci at the bottom of the capillary lead to a pronounced metastability, determined by a complementary Kelvin equation Δp(L) = 2σsinθ cap /L. On approaching the wetting temperature of the capillary cap, the corner menisci merge and a single meniscus unbinds from the bottom of the groove. Finite-size scaling shifts, crossover behaviour and critical singularities are determined at mean-field level and beyond. Numerical and experimental results showing the continuous nature of condensation for θ cap = 0 and the influence of corner menisci on adsorption isotherms are presented. (fast track communication)

  14. Capillary condensation of short-chain molecules.

    Science.gov (United States)

    Bryk, Paweł; Pizio, Orest; Sokolowski, Stefan

    2005-05-15

    A density-functional study of capillary condensation of fluids of short-chain molecules confined to slitlike pores is presented. The molecules are modeled as freely jointed tangent spherical segments with a hard core and with short-range attractive interaction between all the segments. We investigate how the critical parameters of capillary condensation of the fluid change when the pore width decreases and eventually becomes smaller than the nominal linear dimension of the single-chain molecule. We find that the dependence of critical parameters for a fluid of dimers and of tetramers on pore width is similar to that of the monomer fluid. On the other hand, for a fluid of chains consisting of a larger number of segments we observe an inversion effect. Namely, the critical temperature of capillary condensation decreases with increasing pore width for a certain interval of values of the pore width. This anomalous behavior is also influenced by the interaction between molecules and pore walls. We attribute this behavior to the effect of conformational changes of molecules upon confinement.

  15. The order of condensation in capillary grooves.

    Science.gov (United States)

    Rascón, Carlos; Parry, Andrew O; Nürnberg, Robert; Pozzato, Alessandro; Tormen, Massimo; Bruschi, Lorenzo; Mistura, Giampaolo

    2013-05-15

    We consider capillary condensation in a deep groove of width L. The transition occurs at a pressure p(co)(L) described, for large widths, by the Kelvin equation p(sat) - p(co)(L) = 2σ cosθ/L, where θ is the contact angle at the side walls and σ is the surface tension. The order of the transition is determined by the contact angle of the capped end θcap; it is continuous if the liquid completely wets the cap, and first-order otherwise. When the transition is first-order, corner menisci at the bottom of the capillary lead to a pronounced metastability, determined by a complementary Kelvin equation Δp(L) = 2σ sinθcap/L. On approaching the wetting temperature of the capillary cap, the corner menisci merge and a single meniscus unbinds from the bottom of the groove. Finite-size scaling shifts, crossover behaviour and critical singularities are determined at mean-field level and beyond. Numerical and experimental results showing the continuous nature of condensation for θcap = 0 and the influence of corner menisci on adsorption isotherms are presented.

  16. Glass leaching performance

    International Nuclear Information System (INIS)

    Chick, L.A.; Turcotte, R.P.

    1983-05-01

    Current understanding of the leaching performance of high-level nuclear waste (HLW) glass is summarized. The empirical model of waste glass leaching behavior developed shows that at high water flow rates the glass leach rate is kinetically limited to a maximum value. At intermediate water flow rates, leaching is limited by the solution concentration of silica and decreases with decreasing water flow rates. Release of soluble elements is controlled by silica dissolution because silica forms the binding network of the glass. At low water flow rates, mass loss rates reach values controlled by formation rates of alteration minerals, or by diffusion of dissolution products through essentially stagnant water. The parameters reviewed with respect to their quantifiable influence on leaching behavior include temperature, pH, leachant composition, glass composition, thermal history, and radiation. Of these, temperature is most important since the rate of mass loss approximately doubles with each 10 0 C increase in dilute solutions. The pH has small effects within the 4 to 10 range. The chemical composition of the leachant is most important with regard to its influence on alteration product formation. Glass composition exhibits the largest effects at high flow rates where improved glasses leach from ten to thirty times slower than glass 76 to 68. The effects of the thermal history (devitrification) of the glass are not likely to be significant. Radiation effects are important primarily in that radiolysis can potentially drive pH values to less than 4. Radiation damage to the glass causes insignificant changes in leaching performance

  17. Picobubble enhanced column flotation of fine coal

    Energy Technology Data Exchange (ETDEWEB)

    Tao, D.; Yu, S.; Parekh, B.K. [University of Kentucky, Lexington, KY (United States). Mining Engineering

    2006-07-01

    The purpose is to study the effectiveness of picobubbles in the column flotation of -28 mesh fine coal particles. A flotation column with a picobubble generator was developed and tested for enhancing the recovery of ultrafine coal particles. The picobubble generator was designed using the hydrodynamic cavitation principle. A metallurgical and a steam coal were tested in the apparatus. The results show that the use of picobubbles in a 2in. flotation column increased the recovery of fine coal by 10 to 30%. The recovery rate varied with feed rate, collector dosage, and other column conditions. 40 refs., 8 figs., 2 tabs.

  18. Laser surface wakefield in a plasma column

    International Nuclear Information System (INIS)

    Gorbunov, L.M.; Mora, P.; Ramazashvili, R.R.

    2003-01-01

    The structure of the wakefield in a plasma column, produced by a short intense laser pulse, propagating through a gas affected by tunneling ionization is investigated. It is shown that besides the usual plasma waves in the bulk part of the plasma column [see Andreev et al., Phys. Plasmas 9, 3999 (2002)], the laser pulse also generates electromagnetic surface waves propagating along the column boundary. The length of the surface wake wave substantially exceeds the length of the plasma wake wave and its electromagnetic field extends far outside the plasma column

  19. Study on the dynamic holdup distribution of the pulsed extraction column

    International Nuclear Information System (INIS)

    Wang, S.; Chen, J.; Wu, Q.

    2013-01-01

    In the study, a CSTR cascade dynamic hydraulic model was developed to investigate the dynamic holdup distribution of the pulsed extraction column. It is assumed that the dynamic process of the dispersed phase holdup of pulsed extraction column has equal effects with the operational process of multiple cascade CSTRs. The process is consistent with the following assumptions: the holdups vary on different stages but maintain uniform on each stage; the changes of the hydraulic parameters have impact initially on the inlet of dispersed phase, and stability will be reached gradually through stage-by-stage blending. The model was tested and verified utilizing time domain response curves of the average holdup. Nearly 150 experiments were carried out with different capillary columns, various feed liquids, and diverse continuous phases and under different operation conditions. The regression curves developed by the model show a good consistency with the experimental results. After linking parameters of the model with operational conditions, the study further found that the parameters are only linearly correlated with pulse conditions and have nothing to do with flow rate for a specific pulsed extraction column. The accuracy of the model is measured by the average holdup, and the absolute error is ±0.01. The model can provide supports for the boundary studies on hydraulics and mass transfer by making simple and reliable prediction of the dynamic holdup distribution, with relatively less accessible hydraulic experimental data. (authors)

  20. Study on the dynamic holdup distribution of the pulsed extraction column

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S.; Chen, J.; Wu, Q. [Tsinghua University, Beijing 100084 (China)

    2013-07-01

    In the study, a CSTR cascade dynamic hydraulic model was developed to investigate the dynamic holdup distribution of the pulsed extraction column. It is assumed that the dynamic process of the dispersed phase holdup of pulsed extraction column has equal effects with the operational process of multiple cascade CSTRs. The process is consistent with the following assumptions: the holdups vary on different stages but maintain uniform on each stage; the changes of the hydraulic parameters have impact initially on the inlet of dispersed phase, and stability will be reached gradually through stage-by-stage blending. The model was tested and verified utilizing time domain response curves of the average holdup. Nearly 150 experiments were carried out with different capillary columns, various feed liquids, and diverse continuous phases and under different operation conditions. The regression curves developed by the model show a good consistency with the experimental results. After linking parameters of the model with operational conditions, the study further found that the parameters are only linearly correlated with pulse conditions and have nothing to do with flow rate for a specific pulsed extraction column. The accuracy of the model is measured by the average holdup, and the absolute error is ±0.01. The model can provide supports for the boundary studies on hydraulics and mass transfer by making simple and reliable prediction of the dynamic holdup distribution, with relatively less accessible hydraulic experimental data. (authors)

  1. Innovative method of direct determination of the content of paraffins, naphthenes, aromatics and sulfur compounds by capillary high-resolution gas chromatography

    Directory of Open Access Journals (Sweden)

    R. Baizhumanova

    2012-03-01

    Full Text Available Based on determination of individual Hydrocarbon (paraffins, naphthenes, aromatics and Sulphur components of fuels and their mixture on the thin bonded of absorber (the stationary phase is a 100-metre silica capillary column, containing 0.5μm film thickness of bonded dimethylpolysiloxane phase by means of the selective solvents (mobile phase combined with technique of ionization of separated compounds by Flame Ionization Detector (FID and Sulphur Chemiluminescence Detector (SCD.

  2. Proper Use of Capillary Number in Chemical Flooding

    Directory of Open Access Journals (Sweden)

    Hu Guo

    2017-01-01

    Full Text Available Capillary number theory is very important for chemical flooding enhanced oil recovery. The difference between microscopic capillary number and the microscopic one is easy to confuse. After decades of development, great progress has been made in capillary number theory and it has important but sometimes incorrect application in EOR. The capillary number theory was based on capillary tube bundles and Darcy’s law hypothesis, and this should always be kept in mind when used in chemical flooding EOR. The flow in low permeability porous media often shows obvious non-Darcy effects, which is beyond Darcy’s law. Experiments data from ASP flooding and SP flooding showed that remaining oil saturation was not always decreasing as capillary number kept on increasing. Relative permeability was proved function of capillary number; its rate dependence was affected by capillary end effects. The mobility control should be given priority rather than lowering IFT. The displacement efficiency was not increased as displacement velocity increased as expected in heavy oil chemical flooding. Largest capillary number does not always make highest recovery in chemical flooding in heterogeneous reservoir. Misuse of CDC in EOR included the ignorance of mobility ratio, Darcy linear flow hypothesis, difference between microscopic capillary number and the microscopic one, and heterogeneity caused flow regime alteration. Displacement of continuous oil or remobilization of discontinuous oil was quite different.

  3. Measurement of Capillary Radius and Contact Angle within Porous Media.

    Science.gov (United States)

    Ravi, Saitej; Dharmarajan, Ramanathan; Moghaddam, Saeed

    2015-12-01

    The pore radius (i.e., capillary radius) and contact angle determine the capillary pressure generated in a porous medium. The most common method to determine these two parameters is through measurement of the capillary pressure generated by a reference liquid (i.e., a liquid with near-zero contact angle) and a test liquid. The rate of rise technique, commonly used to determine the capillary pressure, results in significant uncertainties. In this study, we utilize a recently developed technique for independently measuring the capillary pressure and permeability to determine the equivalent minimum capillary radii and contact angle of water within micropillar wick structures. In this method, the experimentally measured dryout threshold of a wick structure at different wicking lengths is fit to Darcy's law to extract the maximum capillary pressure generated by the test liquid. The equivalent minimum capillary radii of different wick geometries are determined by measuring the maximum capillary pressures generated using n-hexane as the working fluid. It is found that the equivalent minimum capillary radius is dependent on the diameter of pillars and the spacing between pillars. The equivalent capillary radii of micropillar wicks determined using the new method are found to be up to 7 times greater than the current geometry-based first-order estimates. The contact angle subtended by water at the walls of the micropillars is determined by measuring the capillary pressure generated by water within the arrays and the measured capillary radii for the different geometries. This mean contact angle of water is determined to be 54.7°.

  4. Use of tapered Pyrex capillary tubes to increase the mechanical stability of multiwall carbon nanotubes field emitters

    Science.gov (United States)

    Mousa, M. S.; Bani Ali, E. S.; Hagmann, M. J.

    2018-02-01

    In this study, NanocylTM NC 7000 Thin Multiwall Carbon Nanotubes (MWCNTs) were used with a high aspect ratio (>150) made by the process of catalytic chemical vapor deposition (CCVD). The field emitter tips were prepared by inserting these MWCT into fine glass capillary tubes that were pulled at high temperatures and then cut. Measurements were carried out under ultra-high vacuum (UHV) conditions with a base pressure of 10-9 mbar. The data show the effects of initial conditioning of MWCNT and hysteresis. Compression of the MWCNT by the capillary tubes appears to provide adequate mechanical support without requiring the use of a low-melting point electrically-conductive binder as has been used previously. Emission currents in excess of 1 μA were obtained so this technique shows promise as a reliable, stable, powerful electron source.

  5. Influence of granulometry in the Hurst exponent of air liquid interfaces formed during capillary rising in a granular media

    Directory of Open Access Journals (Sweden)

    Gontijo Guilherme L.

    2017-01-01

    Full Text Available We report results concerning the fractal dimension of a air/fluid interface formed during the capillary rising of a fluid into a dense granular media. The system consists in a modified Hele-Shaw cell filled with grains at different granulometries and confined in a narrow gap between the glass plates. The system is then placed onto a water reservoir, and the liquid penetrates the medium due to capillary forces. We measure the Hurst exponent of the liquid/air interface with help of image processing, and follow the temporal evolution of the profiles. We observe that the Hurst exponent can be related with the granulometry, but the range of values are odd to the predicted values from models or theory.

  6. Mechanized Sephadex LH-20 multiple column chromatography as a prerequisite for automated multi-steroid radioimmunoassays

    International Nuclear Information System (INIS)

    Sippell, W.G.; Bidlingmaier, F.; Knorr, D.

    1978-01-01

    To establish a procedure for the simultaneous determination of all major corticosteroid hormones and their immediate biological precursors in the same plasma sample, two different mechanized methods for the simultaneous isolation of aldosterone (A), corticosterone (B), 11-deoxycorticosterone (DOC), progesterone (P), 17-hydroxyprogesterone (17-OHP), 11-deoxycortisol (S), cortisol (F) and cortisone (E) from the methylene chloride extracts of 0.1 to 2.0ml plasma samples have been developed. In method I, steroids are separated with methylene chloride:methanol=98:2 as solvent system on 60-cm Sephadex LH-20 columns, up to eight of which are eluted in parallel using a multi-channel peristaltic pump and individual flow-rate control (40ml/h) by capillary valves and micro-flowmeters. Method II, on the other hand, utilizes the same solvent system on ten 75-cm LH-20 columns which are eluted in reversed flow simultaneously by a ten-channel, double-piston pump that precisely maintains an elution flow rate of 40ml/h in every column. In both methods, eluate fractions of each of the isolated steroids are automatically pooled and collected from all parallel columns by one programmable linear fraction collector. As a result of the high reproducibility of the elution patterns, both between different parallel columns and between 30 to 40 consecutive elutions, mean recoveries of tritiated steroids including extraction are 60 to 84% after a single separation and still over 50% after an additional separation on 40-cm LH-20 columns, with coefficients of variation below 15% (method II). Thus, the eight steroids can be completely isolated from each of ten plasma extracts within 3 to 4 hours, yielding 80 samples readily prepared for subsequent quantitation by radioimmunoassay. (author)

  7. Thermal Conductivity of Foam Glass

    DEFF Research Database (Denmark)

    Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

    Due to the increased focus on energy savings and waste recycling foam glass materials have gained increased attention. The production process of foam glass is a potential low-cost recycle option for challenging waste, e.g. CRT glass and industrial waste (fly ash and slags). Foam glass is used...... as thermal insulating material in building and chemical industry. The large volume of gas (porosity 90 – 95%) is the main reason of the low thermal conductivity of the foam glass. If gases with lower thermal conductivity compared to air are entrapped in the glass melt, the derived foam glass will contain...... only closed pores and its overall thermal conductivity will be much lower than that of the foam glass with open pores. In this work we have prepared foam glass using different types of recycled glasses and different kinds of foaming agents. This enabled the formation of foam glasses having gas cells...

  8. Isotopic fractionation of fentanyl and its deuterated analogues by capillary gas chromatography

    International Nuclear Information System (INIS)

    Sera, Shoji; Goromaru, Tsuyoshi

    1997-01-01

    Isotopic fractionation of fentanyl (FT) and its deuterated analogues by gas chromatography using capillary columns (CBP1 and CBP5) has been investigated. Seven kinds of analogues were labeled with 5 to 19 deuterium atoms at the anilino, propionyl and/or phenylethyl group of FT. The retention times of deuterated FT in CBP1 and CBP5 columns are inversely proportional to the number of labeled deuterium atoms in the molecule. The difference in free enegy changes (ΔΔG) had a linear relationship with the number of labeled deuterium atoms, except for labeling at anilino and phenylethyl group. The contribution of a deuterium atom to the ΔΔG value was estimated to be 1.13 cal/mol in CBP1 and 1.40 cal/mol in CBP5, respectively. While, its contribution in the propiony group was 2.84 cal/mol in CBP1 and 2.48 cal/mol in CBP5, respectively. An important factor in separation by GC may differences in interactions between the stationary phase of the column with the three dimensional protrusive moiety in the molecule. (author)

  9. Isotopic fractionation of fentanyl and its deuterated analogues by capillary gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Sera, Shoji; Goromaru, Tsuyoshi [Fukuyama Univ., Hiroshima (Japan)

    1997-12-01

    Isotopic fractionation of fentanyl (FT) and its deuterated analogues by gas chromatography using capillary columns (CBP1 and CBP5) has been investigated. Seven kinds of analogues were labeled with 5 to 19 deuterium atoms at the anilino, propionyl and/or phenylethyl group of FT. The retention times of deuterated FT in CBP1 and CBP5 columns are inversely proportional to the number of labeled deuterium atoms in the molecule. The difference in free enegy changes ({Delta}{Delta}G) had a linear relationship with the number of labeled deuterium atoms, except for labeling at anilino and phenylethyl group. The contribution of a deuterium atom to the {Delta}{Delta}G value was estimated to be 1.13 cal/mol in CBP1 and 1.40 cal/mol in CBP5, respectively. While, its contribution in the propiony group was 2.84 cal/mol in CBP1 and 2.48 cal/mol in CBP5, respectively. An important factor in separation by GC may differences in interactions between the stationary phase of the column with the three dimensional protrusive moiety in the molecule. (author)

  10. Insights into head-column field-amplified sample stacking: Part II. Study of the behavior of the electrophoretic system after electrokinetic injection of cationic compounds across a short water plug

    Czech Academy of Sciences Publication Activity Database

    Šesták, Jozef; Thormann, W.

    2017-01-01

    Roč. 1512, AUG (2017), s. 124-132 ISSN 0021-9673 Institutional support: RVO:68081715 Keywords : head- column field-amplified sample stacking * capillary electrophoresis * water plug Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 3.981, year: 2016

  11. Insights into head-column field-amplified sample stacking: Part II. Study of the behavior of the electrophoretic system after electrokinetic injection of cationic compounds across a short water plug

    Czech Academy of Sciences Publication Activity Database

    Šesták, Jozef; Thormann, W.

    2017-01-01

    Roč. 1512, AUG (2017), s. 124-132 ISSN 0021-9673 Institutional support: RVO:68081715 Keywords : head-column field-amplified sample stacking * capillary electrophoresis * water plug Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 3.981, year: 2016

  12. Nde of Frp Wrapped Columns Using Infrared Thermography

    Science.gov (United States)

    Halabe, Udaya B.; Dutta, Shasanka Shekhar; GangaRao, Hota V. S.

    2008-02-01

    This paper investigates the feasibility of using Infrared Thermography (IRT) for detecting debonds in Fiber Reinforced Polymer (FRP) wrapped columns. Laboratory tests were conducted on FRP wrapped concrete cylinders of size 6″×12″ (152.4 mm×304.8 mm) in which air-filled and water-filled debonds of various sizes were placed underneath the FRP wraps. Air-filled debonds were made by cutting plastic sheets into the desired sizes whereas water-filled debonds were made by filling water in custom made polyethylene pouches. Both carbon and glass fiber reinforced wraps were considered in this study. Infrared tests were conducted using a fully radiometric digital infrared camera which was successful in detecting air-filled as well as water-filled subsurface debonds. In addition to the laboratory testing, two field trips were made to Moorefield, West Virginia for detecting subsurface debonds in FRP wrapped timber piles of a railroad bridge using infrared testing. The results revealed that infrared thermography can be used as an effective nondestructive evaluation tool for detecting subsurface debonds in structural components wrapped with carbon or glass reinforced composite fabrics.

  13. Effect of different glasses in glass bonded zeolite

    International Nuclear Information System (INIS)

    Lewis, M.A.; Ackerman, J.P.; Verma, S.

    1995-01-01

    A mineral waste form has been developed for chloride waste salt generated during the pyrochemical treatment of spent nuclear fuel. The waste form consists of salt-occluded zeolite powders bound within a glass matrix. The zeolite contains the salt and immobilizes the fission products. The zeolite powders are hot pressed to form a mechanically stable, durable glass bonded zeolite. Further development of glass bonded zeolite as a waste form requires an understanding of the interaction between the glass and the zeolite. Properties of the glass that enhance binding and durability of the glass bonded zeolite need to be identified. Three types of glass, boroaluminosilicate, soda-lime silicate, and high silica glasses, have a range of properties and are now being investigated. Each glass was hot pressed by itself and with an equal amount of zeolite. MCC-1 leach tests were run on both. Soda-lime silicate and high silica glasses did not give a durable glass bonded zeolite. Boroaluminosilicate glasses rich in alkaline earths did bind the zeolite and gave a durable glass bonded zeolite. Scanning electron micrographs suggest that the boroaluminosilicate glasses wetted the zeolite powders better than the other glasses. Development of the glass bonded zeolite as a waste form for chloride waste salt is continuing

  14. Column: Factors Affecting Data Decay

    Directory of Open Access Journals (Sweden)

    Kevin Fairbanks

    2012-06-01

    Full Text Available In nuclear physics, the phrase decay rate is used to denote the rate that atoms and other particles spontaneously decompose. Uranium-235 famously decays into a variety of daughter isotopes including Thorium and Neptunium, which themselves decay to others. Decay rates are widely observed and wildly different depending on many factors, both internal and external. U-235 has a half-life of 703,800,000 years, for example, while free neutrons have a half-life of 611 seconds and neutrons in an atomic nucleus are stable.We posit that data in computer systems also experiences some kind of statistical decay process and thus also has a discernible decay rate. Like atomic decay, data decay fluctuates wildly. But unlike atomic decay, data decay rates are the result of so many different interplaying processes that we currently do not understand them well enough to come up with quantifiable numbers. Nevertheless, we believe that it is useful to discuss some of the factors that impact the data decay rate, for these factors frequently determine whether useful data about a subject can be recovered by forensic investigation.(see PDF for full column

  15. Gaseous carbon dioxide absorbing column

    International Nuclear Information System (INIS)

    Harashina, Heihachi.

    1994-01-01

    The absorbing column of the present invention comprises a cyclone to which CO 2 gas and Ca(OH) 2 are blown to form CaCO 3 , a water supply means connected to an upper portion of the cyclone for forming a thin water membrane on the inner wall thereof, and a water processing means connected to a lower portion of the cyclone for draining water incorporating CaCO 3 . If a mixed fluid of CO 2 gas and Ca(OH) 2 is blown in a state where a flowing water membrane is formed on the inner wall of the cyclone, formation of CaCO 3 is promoted also in the inside of the cyclone in addition to the formation of CaCO 3 in the course of blowing. Then, formed CaCO 3 is discharged from the lower portion of the cyclone together with downwardly flowing water. With such procedures, solid contents such as CaCO 3 separated at the inner circumferential wall are sent into the thin water membrane, adsorbed and captured, and the solid contents are successively washed out, so that a phenomenon that the solid contents deposit and grow on the inner wall of the cyclone can be prevented effectively. (T.M.)

  16. Evaluation of Tillandsia capillaris Ruiz amd Pav. f. capillaris as biomonitor of atmospheric pollution in Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Pignata, M.L. [Univ. Nacional de Cordoba, Cordoba (Argentina). Facultad de Ciencias Exactas, Fisicas y Naturales]|[Instituto Multidisciplinario de Biologia Vegetal (IMBIV-UNC), Cordoba (Argentina); Wannaz, E.D.; Martinez, M.S.; Caminotti, G. [Univ. Nacional de Cordoba, Cordoba (Argentina). Facultad de Ciencias Exactas, Fisicas y Naturales

    2002-07-01

    The behaviour of Tillandsia capillaris Ruiz and Pav. f. capillaris, when exposed to atmospheric pollutants, was assessed by measuring chemical parameters indicating foliar damage and the contents of some heavy metals. Samples were transplanted to three sites in the City of Cordoba and were collected back after 15, 30, 60 and 90 days of exposure. At the same time, samples coming from the collection site were analyzed for each of said exposure times. Chlorophylls, hydroperoxy conjugated dienes, water contents, malondialdehyde, sulfur, Cu, Pb, Ni, Co, Mn, Zn and Fe were measured in the samples. A Foliar Damage Index was calculated from some of these parameters. (orig.)

  17. Oxynitride glasses: a review

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, A.R.; Clausell, C.; Barba, A.

    2016-07-01

    Oxynitride glasses are special types of silicates or silicoaluminates which have been the object of many studies over the last forty years. They can be prepared by means of various complex methods, leading to variable levels of nitrogen incorporation, though in all cases giving limited transparency in the visible range. More recently, a new family of oxynitride glasses incorporating fluorine has been investigated. This paper outlines the effect of composition, in particular nitrogen and fluorine content, on properties such as glass transition temperature, hardness, Young's modulus, compactness and molar volume. (Author)

  18. Orbital glass in HTSC

    International Nuclear Information System (INIS)

    Kusmartsev, F.V.

    1992-10-01

    The physical reasons why the orbital glass may exist in granular high-temperature superconductors and the existing experimental data appeared recently are discussed. The orbital glass is characterized by the coexistence of the orbital paramagnetic state with the superconducting state and occurs at small magnetic fields H c0 c1 . The transition in orbital glass arises at the critical field H c0 which is inversely proportional to the surface cross-area S of an average grain. In connection with theoretical predictions the possible experiments are proposed. (author). 10 refs

  19. Bioactive glasses and glass-ceramics

    Directory of Open Access Journals (Sweden)

    de Aza, P. N.

    2007-04-01

    Full Text Available Since the late 1960´s, a great interest in the use of bioceramic materials for biomedical applications has been developed. In a previous paper, the authors reviewed crystalline bioceramic materials “sensus stricto”, it is to say, those ceramic materials, constituted for non-metallic inorganic compounds, crystallines and consolidates by thermal treatment of powders at high temperature. In the present review, the authors deal with those called bioactive glasses and glassceramics. Although all of them are also obtained by thermal treatment at high temperature, the first are amorphous and the second are obtained by devitrification of a glass, although the vitreous phase normally prevails on the crystalline phases. After an introduction to the concept of bioactive materials, a short historical review of the bioactive glasses development is made. Its preparation, reactivity in physiological media, mechanism of bonding to living tissues and mechanical strength of the bone-implant interface is also reported. Next, the concept of glass-ceramic and the way of its preparation are exposed. The composition, physicochemical properties and biological behaviour of the principal types of bioactive glasses and glass-ceramic materials: Bioglass®, Ceravital®, Cerabone®, Ilmaplant® and Bioverit® are also reviewed. Finally, a short review on the bioactive-glass coatings and bioactive-composites and most common uses of bioactive-glasses and glass-ceramics are carried out too.

    Desde finales de los años sesenta, se ha despertado un gran interés por el uso de los materiales biocerámicos para aplicaciones biomédicas. En un trabajo previo, los autores hicieron una revisión de los denominados materiales biocerámicos cristalinos en sentido estricto, es decir, de aquellos materiales, constituidos por compuestos inorgánicos no metálicos, cristalinos y consolidados mediante tratamientos térmicos a altas temperaturas. En el presente trabajo, los autores

  20. Capillary density: An important parameter in nailfold capillaroscopy.

    Science.gov (United States)

    Emrani, Zahra; Karbalaie, Abdolamir; Fatemi, Alimohammad; Etehadtavakol, Mahnaz; Erlandsson, Björn-Erik

    2017-01-01

    Nailfold capillaroscopy is one of the various noninvasive bioengineering methods used to investigate skin microcirculation. It is an effective examination for assessing microvascular changes in the peripheral circulation; hence it has a significant role for the diagnosis of Systemic sclerosis with the classic changes of giant capillaries as well as the decline in capillary density with capillary dropout. The decline in capillary density is one of microangiopathic features existing in connective tissue disease. It is detectable with nailfold capillaroscopy. This parameter is assessed by applying quantitative measurement. In this article, we reviewed a common method for calculating the capillary density and the relation between the number of capillaries as well as the existence of digital ulcers, pulmonary arterial hypertension, autoantibodies, scleroderma patterns and different scoring system. Copyright © 2016 Elsevier Inc. All rights reserved.