Sample records for packed distillation column

  1. Aromatically enhanced pear distillates from blanquilla and conference varieties using a packed column.

    PubMed

    Arrieta-Garay, Yanine; García-Llobodanin, Laura; Pérez-Correa, José Ricardo; López-Vázquez, Cristina; Orriols, Ignacio; López, Francisco

    2013-05-22

    Pear distillates are generally produced from the Bartlett variety because of its rich aroma. In this study, a chemical and sensorial comparative examination of pear distillates from the three main varieties grown in Spain (Bartlett, Blanquilla, and Conference) using two distillation systems (copper Charentais alembic and packed column) was undertaken. Volatile compounds were identified by gas chromatography to differentiate the spirits according to pear variety and distillation method. The Bartlett distillates from both distillation systems possessed higher ethyl ester and acetate and lower cis-3-hexen-1-ol and 1-hexanol concentrations. Despite these differences, a sensory analysis panel could distinguish only the Bartlett alembic distillate from the alembic distillates of the other varieties. In contrast, the panel rated the packed-column distillates equally. Therefore, less aromatic pear varieties can be used to produce distillates with aromatic characteristics similar to those of the Bartlett variety if a suitable distillation process is used. PMID:23531091

  2. Utilization of Structured Packing for Energy Savings in Distillation and Absorption Columns 

    E-print Network

    Berven, O. J.; Howard, W. E.

    1986-01-01

    of structured packing make it an effective choice for relieving overloaded conditions in key column zones. Sulzer and Koch Engineering can cite over 35 different installations of this nature, including a crude column in Koch's Rosemount, Minnesota refi nery...

  3. Energy Saving in Distillation Using Structured Packing and Vapor Recompression

    E-print Network

    Hill, J.H.

    "Distillation is a big consumer of energy in process plant operations. A first step to energy cost savings is the use of high efficiency structured packing in place of trays or dumped packings in conventionally operated distillation columns. Larger...

  4. Distillation Column Flooding Predictor

    SciTech Connect

    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/vapor traffic that produce increased contact area and lead to substantial increases in separation efficiency – which translates to a 10% increase in energy efficiency on a BTU/bbl basis. The Flooding Predictor™ operates on the principle that between five to sixty minutes in advance of a flooding event, certain column variables experience an oscillation, a pre-flood pattern. The pattern recognition system of the Flooding Predictor™ utilizes the mathematical first derivative of certain column variables to identify the column’s pre-flood pattern(s). This pattern is a very brief, highly repeatable, simultaneous movement among the derivative values of certain column variables. While all column variables experience negligible random noise generated from the natural frequency of the process, subtle pre-flood patterns are revealed among sub-sets of the derivative values of column variables as the column approaches its hydraulic limit. The sub-set of column variables that comprise the pre-flood pattern is identified empirically through in a two-step process. First, 2ndpoint’s proprietary off-line analysis tool is used to mine historical data for pre-flood patterns. Second, the column is flood-tested to fine-tune the pattern recognition for commissioning. Then the Flooding Predictor™ is implemented as closed-loop advanced control strategy on the plant’s distributed control system (DCS), thus automating control of the column at its hydraulic limit.

  5. Heat Exchanger Technologies for Distillation Columns 

    E-print Network

    Polley, G. T.

    2002-01-01

    component rather than the mixture bubble point (assumed with the 'integral' assumption) (Figure 2). ITvapoUT I [./"-------' Where separation occurs, part of the bundle is 'submerged' in condensate. This 'subennergence' can give rise to significant... should be given a downward incline of 3-SO. Intermediate Condensers The extraction of heat from an intermediate point in a distillation column as heat source for a heat pump or for use in an integration scheme can result in significant energy...

  6. Integrated Thermal and Hydraulic Analysis of Distillation Columns 

    E-print Network

    Samant, K.; Sinclair, I.; Keady, G.

    2002-01-01

    Integrated Thermal and Hydraulic Analysis of Distillation Columns Ketan Samant, Aspen Technology Ian Sinclair, Aspen Technology Ginger Keady, Aspen Technology This paper outlines the implementation of column thermal and hydraulic analysis in a...

  7. Time requirements for heteroazeotropic distillation in batch columns

    Microsoft Academic Search

    S. Skouras; Sigurd Skogestad

    2004-01-01

    Batch time requirements are provided for the separation of ternary heterogeneous azeotropic mixtures into three pure products in closed batch column configurations. The separations are performed in hybrid processes where distillation is combined with decantation for completing the separation task. Two multivessel column configurations, with and without vapour bypass, and a rectifier column, are compared in terms of time requirements.

  8. Future perspectives of using hollow fibers as structured packings in light hydrocarbon distillation

    SciTech Connect

    Yang, Dali [Los Alamos National Laboratory; Orler, Bruce [Los Alamos National Laboratory; Tornga, Stephanie [Los Alamos National Laboratory; Welch, Cindy [Los Alamos National Laboratory

    2011-01-26

    Olefin and paraffin are the largest chemical commodities. Furthermore, they are major building blocks for the petrochemical industry. Each year, petroleum refining, consumes 4,500 TBtu/yr in separation energy, making it one of the most energy-intensive industries in the United States). Just considering liquefied petroleum gas (ethane/propane/butane) and olefins (ethylene and propylene) alone, the distillation energy consumption is about 400 TBtu/yr in the US. Since petroleum distillation is a mature technology, incremental improvements in column/tray design will only provide a few percent improvements in the performance. However, each percent saving in net energy use amounts to savings of 10 TBtu/yr and reduces CO{sub 2} emissions by 0.2 MTon/yr. In practice, distillation columns require 100 to 200 trays to achieve the desired separation. The height of a transfer unit (HTU) of conventional packings is typical in the range of 36-60 inch. Since 2006, we had explored using several non-selective membranes as the structured packings to replace the conventional packing materials used in propane and propylene distillation. We obtained the lowest HTU of < 8 inch for the hollow fiber column, which was >5 times shorter than that of the conventional packing materials. In 2008, we also investigated this type of packing materials in iso-/n-butane distillation. Because of a slightly larger relative volatility of iso-/n-butane than that of propane/propylene, a wider and a more stable operational range was obtained for the iso-/n-butane pair. However, all of the experiments were conducted on a small scale with flowrate of < 25 gram/min. Recently, we demonstrated this technology on a larger scale (<250 gram/min). Within the loading range of F-factor < 2.2 Pa{sup 0.5}, a pressure drop on the vapor side is below 50 mbar/m, which suggests that the pressure drop of hollow fibers packings is not an engineering barrier for the applications in distillations. The thermal stability study suggests that polypropylene hollow fibers are stable after a long time exposure to C{sub 2} - C{sub 4} mixtures. The effects of packing density on the separation efficiency will be discussed.

  9. Experimental study of wave propagation dynamics of multicomponent distillation columns

    SciTech Connect

    Ting, J.; Helfferich, F.G.; Hwang, Y.L.; Graham, G.K.; Keller, G.E. II

    1999-10-01

    Distillation columns with sharp separations exhibit severely nonlinear behavior, which has been known to cause difficulties in column control and design. Such a column is characterized by sharp composition and temperature variations in the column. Previously, the binary distillation case was thoroughly analyzed using a nonlinear wave theory and such an analysis was experimentally validated. For multicomponent distillation, the complicated nonlinear dynamics of the movement and interference of multiple sharp composition variations can be elucidated with a coherent-wave theory developed earlier for general countercurrent separation processes. With a ternary alcohol mixture, the present study has experimentally verified the theory by demonstrating the existence and propagation of constant-pattern coherent waves in a 50-tray stripping column in response to a step disturbance of feed composition, feed flow rate, or reboiler heat supply. The study has also tested the theory's predictions of composition profile, wave velocities, and asymmetric dynamics.

  10. Control of a Industrial Heat Integrated Distillation Column T. Larsson and S. Skogestad

    E-print Network

    Skogestad, Sigurd

    Control of a Industrial Heat Integrated Distillation Column T. Larsson and S. Skogestad Department integrated distillation columns are used to reduce the energy consumption for separation. The heat inte- grated distillation columns will behave differently than two normal heat integrated distillation column

  11. Control of a Industrial Heat Integrated Distillation Column T. Larsson and S. Skogestad

    E-print Network

    Skogestad, Sigurd

    Control of a Industrial Heat Integrated Distillation Column T. Larsson and S. Skogestad Department integrated distillation columns are used to reduce the energy consumption for separation. The heat inte­ grated distillation columns will behave differently than two normal heat integrated distillation column

  12. Mass transfer in aqueous two-phases system packed column

    Microsoft Academic Search

    L Igarashi; T. G Kieckbusch; T. T Franco

    2004-01-01

    The behavior of xylanase extraction in a packed column using polyethylene glycol (PEG) 4000 and dipotassium phosphate was studied. The possibility of using the packed column in continuous operations for enzyme extraction was studied since the previous work had only addressed the semi-continuous extraction of enzyme. The influence of several kinds of packings, Raschig rings, glass spheres and polystyrene rings

  13. Temperature–enthalpy curve for energy targeting of distillation columns

    Microsoft Academic Search

    Santanu Bandyopadhyay; Ranjan K. Malik; Uday V. Shenoy

    1998-01-01

    The temperature–enthalpy (T–H) diagram of a distillation column at practical near-minimum thermodynamic condition (PNMTC) or the column grand composite curve (CGCC) is a useful representation for energy targeting studies and may be generated from a converged simulation of a base-case column design. The calculation procedure for the CGCC involves determination of the net enthalpy deficit at each stage by generating

  14. CONTROL CONFIGURATION SELECTION FOR DISTILLATION COLUMNS UNDER TEMPERATURE CONTROL

    E-print Network

    Skogestad, Sigurd

    CONTROL CONFIGURATION SELECTION FOR DISTILLATION COLUMNS UNDER TEMPERATURE CONTROL Erik A. Wol#11; and Sigurd Skogestad #3; University of Trondheim N-7034 Trondheim, NORWAY Keywords: process control, cascade control, distilla- tion, control structure, relative gain array 1 Introduction In most process control

  15. Simulated distillation of petroleum and coal-derived products by packed capillary supercritical fluid chromatography

    SciTech Connect

    Robson, M.; Johnson, B.R.; Mitchell, S.C. [Univ. of Leeds (United Kingdom)] [and others

    1995-12-31

    The advantages of simulated distillation (SD) of petroleum compounds by super-critical fluid chromatography (SFC) over high temperature gas chromatography (HTGC) are well recognised. Most of the research performed using this technique has employed conventional open tubular columns but the use of packed capillary columns which offer high sample capacities, greater efficiency of separation and a shorter analysis time has recently received much attention. Previous work at Leeds using a variety of column packings (C{sub 1}-C{sub 18} alkyl groups bonded to silica) has demonstrated that high molecular weight hydrocarbons with boiling points up to 800{degrees}C can be successfully eluted with pure CO{sub 2} as a mobile phase. However, the high compositional variability of coal-derived samples increases the difficulty of SD-SFC of coal fractions as compared to petroleum derived fractions. In this study, a number of coal samples have been investigated to determine the suitability of packed capillary SD-SFC for heavy coal products.

  16. Experimental study of wave propagation dynamics of binary distillation columns

    SciTech Connect

    Hwang, Y.L.; Graham, G.K.; Keller, G.E. II [Union Carbide Corp., South Charleston, WV (United States)] [Union Carbide Corp., South Charleston, WV (United States); Ting, J.; Helfferich, F.G. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Chemical Engineering] [Pennsylvania State Univ., University Park, PA (United States). Dept. of Chemical Engineering

    1996-10-01

    High-purity distillation columns are typically difficult to control because of their severely nonlinear behavior reflected by their sharp composition and temperature profiles. The dynamic behavior of such a column, as characterized by the movement of its sharp profile, was elucidated by a nonlinear wave theory established previously. With binary alcohol mixtures, this study provides an experimental observation of such wave-propagation dynamics of a 40-tray stripping column and a 50-tray fractionation column in response to step disturbances of feed composition, feed flow rate, and reboiler heat supply. These experimental results have verified that the sharp profile in a high-purity column moves as a constant-pattern wave and that the nonlinear wave theory predicts its velocity satisfactorily with very simple mathematics. Results also demonstrate the asymmetric dynamics of the transitions between two steady states.

  17. Applying risk assessment principles to a batch distillation column

    SciTech Connect

    Woodward, J.L.; Moosemiller, M.D. [DNV Technica, Columbus, OH (United States)] [DNV Technica, Columbus, OH (United States)

    1996-12-31

    Some distillation columns in the chemical industry are operated in batch mode with a fairly short operating cycle. At the end of each cycle the columns are cooled and recharged. During the cooling cycle, air will be drawn into the column by the action of a vacuum relief valve. Consequently, for a finite portion of the operating cycle a flammable mixture will exist in the column. Here we evaluate the risk posed by such an operation to see if a mitigation measure is justified. We develop a fault tree and estimate the frequency of ignition by all possible ignition sources. By comparing the risk reduction attainable by installing a lightning protection system with that attainable by using an inert blanketing system the lightning protection system is found to be the preferred solution. It provides about the same risk reduction at a lower overall cost. 2 refs., 3 figs., 4 tabs.

  18. Mass transfer in aqueous two-phases system packed column.

    PubMed

    Igarashi, L; Kieckbusch, T G; Franco, T T

    2004-07-25

    The behavior of xylanase extraction in a packed column using polyethylene glycol (PEG) 4000 and dipotassium phosphate was studied. The possibility of using the packed column in continuous operations for enzyme extraction was studied since the previous work had only addressed the semi-continuous extraction of enzyme. The influence of several kinds of packings, Raschig rings, glass spheres and polystyrene rings were studied as well the superficial velocity ratio of the salt and the PEG phases. Packed column showed a good efficiency of overall mass transfer coefficient, around three times higher than sieve plate column, for xylanase extraction. The best selectivity was obtained with the polystyrene ring where 94% of xylanase was recovery to the polymeric whereas just 3% of contaminant was recovery to this phase. The residence time distribution was adjusted by the Model of Reactors in Series. PMID:15177163

  19. The development of HPLC columns: Packing structure, column efficiency, stability and standardization

    SciTech Connect

    Unger, K.K.; Hallman, M.; Ranis-Jansen, R. [Johannes Gutenberg-Universitat, Mainz (Germany)

    1995-12-01

    Packing procedures for HPLC columns, such as the slurry technique (analytical columns) and the axial compression technique (preparative columns) have been widely established. However, there is still a lack of fundamental knowledge concerning the actual packing structure of a column and its impact on efficiency and stability. Recently, attempts have been made to model the packing procedure as well as the column bed structure and to apply experimental methods to characterize the assembly of microparticles in a column and the elution profiles in situ. The high reproducibility of commercial HPLC columns with respect to efficiency is mainly due to the substantial improvements made in particle technology, column hardware and optimized column packing procedures. The stability of commercial columns is acceptable but very much dependent on the extent of sample clean-up and the column handling and operation by the user. To validate HPLC methods, a project is planned to establish a C18 reversed phase reference column for standardization and certification in the frame of the EC Programme on {open_quotes}Measurements and Testing{open_quotes}.

  20. A GENERALIZED DYNAMIC MODEL FOR DISTILLATION COLUMNS-III. STUDY OF STARTUP OPERATIONS

    Microsoft Academic Search

    C. A. Rurz; I. T. CAMERON; R. GANI

    The dynamic behavior of distillation columns during startup operations have been studied and analyzed. A procedure is proposed for determining appropriate startup policies for distillation column operations based on the analysis of the dynamic behavior. The final startup policy consists of three strategies corresponding to the three characteristic stages of the startup operation. The proposed procedure has been successfully applied

  1. Minimum Energy Consumption in Multicomponent Distillation. 1. Vmin Diagram for a Two-Product Column

    E-print Network

    Skogestad, Sigurd

    Minimum Energy Consumption in Multicomponent Distillation. 1. Vmin Diagram for a Two-Product Column how the minimum energy consumption is related to the feed-component distribution for all possible operating points in a two-product distillation column with a multicomponent feed. The classical Underwood

  2. Effects of helium on separation characteristics of cryogenic distillation column cascade for fusion reactor

    Microsoft Academic Search

    Kinoshita

    1984-01-01

    By choosing the cryogenic distillation column cascade developed at Los Alamos National Laboratory, the effects of helium on separation characteristics of the columns are analyzed in a probable case of input and output specifications. Column (2) is mainly affected by the presence of helium. If the helium percentage in the raw fuel input is 1%, the column performance can be

  3. Temperature effects on nano-LC column packing technology.

    PubMed

    Leonardis, Irene; Capriotti, Fabiana; Cappiello, Achille; Famiglini, Giorgio; Palma, Pierangela

    2012-07-01

    We investigated the effect of temperature on the packing procedure of nano-LC columns (up to 50 cm) and on their performance. Several slurries of stationary phase were prepared using different solvent mixtures. Their stability was evaluated at several temperatures: 70°C, 50°C, and room temperature. At the higher temperature (70°C) the suspensions resulted to be stable for a longer time. For each slurry, we compared nano-LC columns packed with ultrasounds at 70°C and at room temperature. All the columns were tested with a standard mixture at 70°C, to reduce the solvent viscosity and the backpressure. Main chromatographic parameters such as the asymmetry factor, As, the reduced plate high, h, pattern in a Van Deemter plot, the total porosity, ?(t), and the permeability, k, were calculated and discussed. One of the nano-LC columns was used to separate a mixture of pesticides in a LC-MS system with an electron ionization LC-MS interface (Direct-EI). From our knowledge, this is the first study on the role of temperature in the efficiency of slurry-packing procedure. PMID:22761136

  4. METHOD TO TEST ISOTOPIC SEPARATION EFFICIENCY OF PALLADIUM PACKED COLUMNS

    SciTech Connect

    Heung, L; Gregory Staack, G; James Klein, J; William Jacobs, W

    2007-06-27

    The isotopic effect of palladium has been applied in different ways to separate hydrogen isotopes for many years. At Savannah River Site palladium deposited on kieselguhr (Pd/k) is used in a thermal cycling absorption process (TCAP) to purify tritium for over ten years. The need to design columns for different throughputs and the desire to advance the performance of TCAP created the need to evaluate different column designs and packing materials for their separation efficiency. In this work, columns with variations in length, diameter and metal foam use, were tested using an isotope displacement method. A simple computer model was also developed to calculate the number of theoretical separation stages using the test results. The effects of column diameter, metal foam and gas flow rate were identified.

  5. Glycolipid class profiling by packed-column subcritical fluid chromatography.

    PubMed

    Deschamps, Frantz S; Lesellier, Eric; Bleton, Jean; Baillet, Arlette; Tchapla, Alain; Chaminade, Pierre

    2004-06-18

    The potential of packed-column subcritical fluid chromatography (SubFC) for the separation of lipid classes has been assessed in this study. Three polar stationary phases were checked: silica, diol, and poly(vinyl alcohol). Carbon dioxide (CO2) with methanol as modifier was used as mobile phase and detection performed by evaporative light scattering detection. The influence of methanol content, temperature, and pressure on the chromatographic behavior of sphingolipids and glycolipids were investigated. A complete separation of lipid classes from a crude wheat lipid extract was achieved using a modifier gradient from 10 to 40% methanol in carbon dioxide. Solute selectivity was improved using coupled silica and diol columns in series. Because the variation of eluotropic strength depending on the fluid density changes, a normalized separation factor product (NSP) was used to select the nature, the number and the order of the columns to reach the optimum glycolipid separation. PMID:15248431

  6. High Performance Trays and Heat Exchangers in Heat Pumped Distillation Columns 

    E-print Network

    Wisz, M. W.; Antonelli, R.; Ragi, E. G.

    1981-01-01

    Vapor recompression of distillation columns overheads, followed by subsequent condensation in the reboiler results in substantial operating cost savings compared to conventional steam driven reboiler systems. The use of high performance heat...

  7. High Performance Trays and Heat Exchangers in Heat Pumped Distillation Columns

    E-print Network

    Wisz, M. W.; Antonelli, R.; Ragi, E. G.

    1981-01-01

    Vapor recompression of distillation columns overheads, followed by subsequent condensation in the reboiler results in substantial operating cost savings compared to conventional steam driven reboiler systems. The use of high performance heat...

  8. Development of dynamic models of reactive distillation columns for simulation and determination of control 

    E-print Network

    Chakrabarty, Arnab

    2005-02-17

    Dynamic models of a reactive distillation column have been developed and implemented in this work. A model describing the steady state behavior of the system has been built in a first step. The results from this steady ...

  9. Homogeneous azeotropic distillation in an energy- and mass-integrated pressure swing column system

    Microsoft Academic Search

    Jens-Uwe Repke; Andreas Klein; Florian Forner

    2004-01-01

    The separation of a homogeneous azeotropic mixture using the pressure swing distillation process is insufficient researched and therefore industrial applications are limited. The process performance of a heat- and mass-integrated pressure swing distillation column system to separate an acetonitril\\/water mixture is analysed in the scope of this paper. Different control structures are developed and compared by using a rigorous dynamic

  10. State Space Modeling and Predictive Control of a Binary Batch Distillation Column

    Microsoft Academic Search

    Zhiyun Zou; Dehong Yu; Zhen Hu; Ning Guo; Luping Yu; Wenqiang Feng

    2006-01-01

    A linear discrete state-space model of a methanol\\/water binary batch distillation column is developed based on theoretical analysis of dynamic mass balance and vapor-liquid phase balance, and this state-space model is used to design a model predictive control (MPC) strategy. The composition of methanol inside the distillation column is estimated using an empirical temperature-composition relationship model. The state space model

  11. Rolled, continuous stationary phase columns from textile fabrics: Optical packing and protein separation

    Microsoft Academic Search

    Chenghong Li

    2001-01-01

    Rolled, continuous stationary phases were constructed by tightly rolling and packing a whole piece of textile woven fabric into a chromatography column. Columns packed in this manner possess important features such as low intraparticle mass transfer and high pressure endurance. These properties, as reflected by a reduction of residence time within a column, show promise in decreasing protein purification costs

  12. Integrated Thermal and Hydraulic Analysis of Distillation Columns

    E-print Network

    Samant, K.; Sinclair, I.; Keady, G.

    This paper outlines the implementation of column thermal and hydraulic analysis in a simulation environment. The methodology is described using a separations example. Column Thermal Analysis has been discussed in the literature extensively...

  13. A modified model of computational mass transfer for distillation column

    Microsoft Academic Search

    Z. M. Sun; K. T. Yu; X. G. Yuan; C. J. Liu

    2007-01-01

    The computational mass transfer (CMT) model is composed of the basic differential mass transfer equation, closing with auxiliary equations, and the appropriate accompanying CFD formulation. In the present modified CMT model, the closing auxiliary equations c2¯–?c [Liu, B.T., 2003. Study of a new mass transfer model of CFD and its application on distillation tray. Ph.D. Dissertation, Tianjin University, Tianjin, China;

  14. Determination of plate efficiencies for conventional distillation columns 

    E-print Network

    Harris, Thomas Raymond

    1962-01-01

    in the oalculational procedures are also discussed. This calculational method employs the equations of Thiele and Qeddes (61) with modifications by Hummel (&1) and Donnel and Turbin (21). Certain notational conventions proposed by Lyster et al. (b0) are used... OF ILLUSTRATIONS FIGURE 1. Convsntional Distillation Coleman . ~ ~ ~ 57 LIST OF TABLES TABLE PAGE I. Specifications for Examples 1, 2, and 4 . . . ~ . . 58 Values oi Ei, Gi, and $ Obtained After the 50'th Trial in the Soluticn of Examples 1 and 2 . 60 1110...

  15. Exact electric field strength over the packed capillary electrochromatography column bed, theoretical considerations and practical determination.

    PubMed

    Guo, Wei; Yang, Changhua; Xu, Bingjiu

    2004-12-01

    On the basis of the experiments, it was proved that Ohm's law holds true in a capillary electrochromatography (CEC) column. By using the additivity of the potential drop over the packed and unpacked sections, the exact values of the electric field strength over the packed CEC column bed were determined experimentally. The ratio of the resistance of packed CEC column sections to that of an open capillary of the same length (Rp/Ro,Lp) were calculated. Some theoretical calculations were made to show how some structural parameters of particle lattice affect the resulting Rp/Ro,Lp value of the column bed formed accordingly. It is suggested that to correctly elucidate the EOF phenomenon in a CEC column, the potential drop over the packed and unpacked column sections, Ep and Eo, should be accounted for respectively, rather than using the average field strength over the total column length. PMID:15628139

  16. Distillation of a Complex Mixture. Part II: Performance Analysis of a Distillation Column Using Exergy

    NASA Astrophysics Data System (ADS)

    Mustapha, Douani; Sabria, Terkhi; Fatima, Ouadjenia

    2007-09-01

    To analyze the performance of the separation process, we have introduced thethermodynamic concept of exergy through the exergetic efficiency of the column. Thesimulation results show that the exergetic output is relatively low and that the producedirreversibility fluxes are distributed throughout the whole column in a non-uniform manner.They are particularly significant in the condenser, boiler and tray feed. The influence of thevarious operating parameters (temperature, concentration and irreversibility in both sectionsof the column) is also established. To emphasize the results, the relation in equation 17, ispresented graphically to evaluate the cumulative irreversibilities from the overhead to thebottom. This presentation is equivalent to the Grassmann diagram.

  17. Distillation of a Complex Mixture. Part I: High Pressure Distillation Column Analysis: Modeling and Simulation

    NASA Astrophysics Data System (ADS)

    Mustapha, Douani; Fatima, Ouadjenia; Sabria, Terkhi

    2007-06-01

    In this analysis, based on the bubble point method, a physical model wasestablished clarifying the interactions (mass and heat) between the species present in thestreams in circulation in the column. In order to identify the externally controlled operatingparameters, the degree of freedom of the column was determined by using Gibbs phase rule.The mathematical model converted to Fortran code and based on the principles of: 1) Globaland local mass conservation balance, 2) Enthalpy balance, and 3) Vapour-liquid equilibriumat each tray, was used to simulate the behavior of the column, concentration distributions,temperature and streams for each phase along the column at high pressure in each tray. Theenergy consumption at the condenser and the boiler was also evaluated using the Starlingequation of state.

  18. Azeotropic distillation in a middle vessel batch column. 1: Model formulation and linear separation boundaries

    Microsoft Academic Search

    Weiyang Cheong; Paul I. Barton

    1999-01-01

    A mathematical model for the middle vessel batch distillation column (MVC) is developed using the concept of warped time analysis and used to study the qualitative dynamics of the MVC when it is used to separate multicomponent azeotropic mixtures. A limiting analysis is then developed for a MVC with an infinite number of trays, operated under infinite reflux\\/reboil ratios, under

  19. Prediction of the Trayed Distillation Column Mass-Transfer Performance by Neural Networks

    E-print Network

    Eldridge, R. Bruce

    Prediction of the Trayed Distillation Column Mass-Transfer Performance by Neural Networks Eric modeled using a neural network. The database developed by Garcia and Fair (Ind. Eng. Chem. Res. 2000, 39, 1809) was utilized to train and validate the neural network model. The results indicate that

  20. A nonlinear profile observer using tray temperatures for high-purity binary distillation column control

    Microsoft Academic Search

    Joonho Shin; Hodong Seo; Myungwan Han

    2000-01-01

    A new, concise nonlinear profile position observer using tray temperatures instead of tray compositions is proposed. Composition measurement has been one of the major difficulties associated with the composition control of distillation columns because the on-line analyzers still suffer from large measurement delays, high investment\\/maintenance costs and low reliability. One of common alternatives to the analyzers is to use the

  1. Effect of Dissolved Oxygen on Removal of Nitrate in Laboratory Columns Packed with Solid Organic Carbon

    Microsoft Academic Search

    Jin Zanfang; Jin Mantong; Li Feili; Pan Zhiyan; Wan Yu; Chen Yingxu; Huang Yanhong

    2011-01-01

    Effect of dissolved oxygen (DO) on removal of nitrate from groundwater was studied in laboratory columns packed with solid organic carbon. DO was measured at different height in the column to clarify that there were conditions, aerobic and anoxic, in the column. The paper reactor was not more sensitive than the cotton reactor in the DO effect. the cotton denitrification

  2. Nonlinear model-based control algorithm for a distillation column using software sensor.

    PubMed

    Jana, Amiya Kumar; Samanta, Amar Nath; Ganguly, Saibal

    2005-04-01

    This paper presents the design of model-based globally linearizing control (GLC) structure for a distillation process within the differential geometric framework. The model of a nonideal binary distillation column, whose characteristics were highly nonlinear and strongly interactive, is used as a real process. The classical GLC law is comprised of a transformer (input-output linearizing state feedback), a nonlinear state observer, and an external PI controller. The tray temperature based short-cut observer (TTBSCO) has been used as a state estimator within the control structure, in which all tray temperatures were considered to be measured. Accordingly, the liquid phase composition of each tray was calculated online using the derived temperature-composition correlation. In the simulation experiment, the proposed GLC coupled with TTBSCO (GLC-TTBSCO) outperformed a conventional PI controller based on servo performances with and without measurement noise as well as on regulatory behaviors. In the subsequent part, the GLC law has been synthesized in conjunction with tray temperature based reduced-order observer (GLC-TTBROO) where the distillate and bottom compositions of the distillation process have been inferred from top and bottom product temperatures respectively, which were measured online. Finally, the comparative performance of the GLC-TTBSCO and the GLC-TTBROO has been addressed under parametric uncertainty and the GLC-TTBSCO algorithm provided slightly better performance than the GLC-TTBROO. The resulting control laws are rather general and can be easily adopted for other binary distillation columns. PMID:15868863

  3. A comparison of PCB/pesticide quantitation using packed vs. Magabore columns

    SciTech Connect

    Hansen, M.C.; Schneider, J.F.; Erickson, M.D.

    1989-12-01

    At Argonne National Laboratory (ANL), we are participating in the DOE Environmental Survey Program, which uses Environment Protection Agency (EPA) Contract Laboratory Program (CLP) methods for analysis of environmental samples. For PCB/pesticides, the CLP method requires gas chromatograph/electron capture detector analysis of a primary and secondary column. Currently, samples undergo quantitative analysis on an EPA-required packed column, while confirmation of retention time is on a megabore column. Megabore columns yield higher resolution, which aids in PCB/pesticide identification and improves quantitation. Megabore columns are used in the CLP method for quantitation only after validation of results with the required packed column. To compare the results from both columns, we quantitatively analyzed over 100 water and soil/sediment samples for PCB/pesticides on packed and megabore columns. This study found a wide variance between megabore columns and packed column quantitation, and concluded that no on the type of column was more accurate or precise in PCB/pesticide identification. 4 refs., 6 figs., 7 tabs.

  4. Micro-columns packed with Chlorella vulgaris immobilised on silica gel for mercury speciation

    Microsoft Academic Search

    P. Tajes-Martínez; E. Beceiro-González; S. Muniategui-Lorenzo; D. Prada-Rodríguez

    2006-01-01

    A method has been developed for mercury speciation in water by using columns packed with Chlorella vulgaris immobilised on silica gel. The method involves the retention of CH3Hg+ and Hg2+ in micro-columns prepared by packing immobilised algae in polypropylene tubes, followed by selective and sequential elution with 0.03 and 1.5M HCl for CH3Hg+ and Hg2+, respectively. The adsorption capacity of

  5. Azeotropic distillation in a middle vessel batch column. 1: Model formulation and linear separation boundaries

    SciTech Connect

    Cheong, W.; Barton, P.I. [Massachusetts Inst. of Tech., Cambridge, MA (United States)] [Massachusetts Inst. of Tech., Cambridge, MA (United States)

    1999-04-01

    A mathematical model for the middle vessel batch distillation column (MVC) is developed using the concept of warped time analysis and used to study the qualitative dynamics of the MVC when it is used to separate multicomponent azeotropic mixtures. A limiting analysis is then developed for a MVC with an infinite number of trays, operated under infinite reflux/reboil ratios, under the assumption of linear separation boundaries. It is determined that, under limiting conditions, the distillate product drawn from the MVC is given by the {alpha} limit set of the MVC still pot composition, while the bottoms product drawn from the MVC is given by the {omega} limit set of the MVC still pot composition. The net product composition is determined by taking a convex combination of the two products. The notions of steering the still pot composition, the vector cone of possible motion for the still pot composition, and the equivalency of the MVC to the combined operation of a batch rectifier and a stripper are also explored. The definition of batch distillation regions for the MVC operated at a given value of the middle vessel parameter {lambda}, and the bifurcation of these regions with the variation of {lambda}, are investigated. Lastly, a mathematical model incorporating the concept of warped time is developed for a multivessel column. The MVC can be viewed as a specific case of the multivessel column.

  6. Colloquium: Geometry and optimal packing of twisted columns and filaments

    NASA Astrophysics Data System (ADS)

    Grason, Gregory M.

    2015-04-01

    This Colloquium presents recent progress in understanding constraints and consequences of close-packing geometry of filamentous or columnar materials possessing nontrivial textures, focusing, in particular, on the common motifs of twisted and toroidal structures. The mathematical framework is presented that relates spacing between linelike, filamentous elements to their backbone orientations, highlighting the explicit connection between the interfilament metric properties and the geometry of non-Euclidean surfaces. The consequences of the hidden connection between packing in twisted filament bundles and packing on positively curved surfaces, like the Thomson problem, are demonstrated for the defect-riddled ground states of physical models of twisted filament bundles. The connection between the "ideal" geometry of fibrations of curved three-dimensional space, including the Hopf fibration, and the non-Euclidean constraints of filament packing in twisted and toroidal bundles is presented, with a focus on the broader dependence of metric geometry on the simultaneous twisting and folding of multifilament bundles.

  7. Azeotropic distillation in a middle vessel batch column. 2: Nonlinear separation boundaries

    SciTech Connect

    Cheong, W.; Barton, P.I. [Massachusetts Inst. of Tech., Cambridge, MA (United States)] [Massachusetts Inst. of Tech., Cambridge, MA (United States)

    1999-04-01

    On the basis of the analytical tools developed for the middle vessel column (MVC) operated under limiting conditions, analysis of the qualitative dynamics of the MVC in separating an azeotropic mixture is extended to the more realistic case in which the separation boundaries are nonlinear. The differences between batch stripper pot composition boundaries and batch rectifier pot composition being able to cross these pot composition boundaries. On the basis of these insights, operating procedures are developed in which ternary azeotropic mixtures of acetone, benzene, and chloroform can be separated into their constituent pure components, a separation not achievable with either the batch stripper or the batch rectifier. The operating procedures suggested for separating the ternary azeotropic mixture of acetone, benzene, and chloroform in the MVC are then shown to be the time analogues of sequences of continuous distillation columns that achieve the same separation. On the basis of this space-time analogy, further analogies are developed between the MVC and a continuous column, and it is postulated that many complex separations currently achieved with sequences of continuous columns can also be achieved with a single MVC. Thus, the MVC represents the ultimate multipurpose solvent recovery technology, as it can handle, in a batch multipurpose mode. separations that will otherwise require a dedicated continuous distillation sequence. Finally, the characteristics of perfect MVC batch entrainers, which allow the complete separation of any azeotrope into its constituent pure components in a single MVC, are discussed.

  8. Geometry and Optimal Packing of Twisted Columns and Filaments

    E-print Network

    Gregory M. Grason

    2015-01-30

    This review presents recent progress in understanding constraints and consequences of close-packing geometry of filamentous or columnar materials possessing non-trivial textures, focusing in particular on the common motifs of twisted and toroidal structures. The mathematical framework is presented that relates spacing between line-like, filamentous elements to their backbone orientations, highlighting the explicit connection between the inter-filament {\\it metric} properties and the geometry of non-Euclidean surfaces. The consequences of the hidden connection between packing in twisted filament bundles and packing on positively curved surfaces, like the Thomson problem, are demonstrated for the defect-riddled ground states of physical models of twisted filament bundles. The connection between the "ideal" geometry of {\\it fibrations} of curved three-dimensional space, including the Hopf fibration, and the non-Euclidean constraints of filament packing in twisted and toroidal bundles is presented, with a focus on the broader dependence of metric geometry on the simultaneous twisting and folded of multi-filament bundles.

  9. Soft sensor based composition estimation and controller design for an ideal reactive distillation column.

    PubMed

    Vijaya Raghavan, S R; Radhakrishnan, T K; Srinivasan, K

    2011-01-01

    In this research work, the authors have presented the design and implementation of a recurrent neural network (RNN) based inferential state estimation scheme for an ideal reactive distillation column. Decentralized PI controllers are designed and implemented. The reactive distillation process is controlled by controlling the composition which has been estimated from the available temperature measurements using a type of RNN called Time Delayed Neural Network (TDNN). The performance of the RNN based state estimation scheme under both open loop and closed loop have been compared with a standard Extended Kalman filter (EKF) and a Feed forward Neural Network (FNN). The online training/correction has been done for both RNN and FNN schemes for every ten minutes whenever new un-trained measurements are available from a conventional composition analyzer. The performance of RNN shows better state estimation capability as compared to other state estimation schemes in terms of qualitative and quantitative performance indices. PMID:20887987

  10. Observation of enhanced heat dissipation in columns packed with superficially porous particles.

    PubMed

    Grinias, James P; Keil, Dayley S; Jorgenson, James W

    2014-12-01

    At high flow rates and pressures, columns packed with sub-2 ?m particles suffer from efficiency losses due to frictional heating. The thermal environment of the column (insulated or isothermal) can decrease or magnify these losses. While a number of studies have been conducted demonstrating the improved performance (partially due to the benefits of enhanced thermal conductivity) of columns packed with superficially porous particles, none have made a comparison between sub-2 ?m fully and superficially porous particles in an isothermal environment where radial thermal gradients are maximized and thermal broadening is amplified. Here we show that when such columns are characterized in a recirculating water jacket (providing an isothermal environment), efficiency loss and changes in retention and mobile phase temperature are reduced for sub-2 ?m superficially porous particles compared to sub-2 ?m fully porous particles. PMID:25456605

  11. Photopolymerized sol–gel frits for packed columns in capillary electrochromatography

    Microsoft Academic Search

    Masaru Kato; Maria T. Dulay; Bryson D. Bennett; Joselito P. Quirino; Richard N. Zare

    2001-01-01

    Porous sol–gel frits are fabricated in a capillary column by filling it with a solution of 3-(trimethoxysilyl)propyl methacrylate, hydrochloric acid, water, toluene (porogen), and a photoinitiator (Irgacure 1800) and exposing it to UV light at 365 nm for 5 min. The separation column (30 cm×75 ?m I.D.) contains between the inlet and outlet frits a 15-cm packed segment filled with

  12. Penetration of different human pathogenic viruses into sand columns percolated with distilled water, groundwater, or wastewater.

    PubMed Central

    Dizer, H; Nasser, A; Lopez, J M

    1984-01-01

    The adsorption of several enteroviruses and rotavirus SA11 to sand from an aquifer in the Federal Republic of Germany was estimated in sand-filled columns loaded with ca. 10(7) PFU and run at a velocity of 2.5 m/day for 12 h. After either distilled water, groundwater, secondary effluent, or tertiary effluent was percolated, the sand core was slowly extruded out of the column and cut in 1-cm slices. The slices were eluted with nutrient broth, and the amount of viruses in the broth was estimated. The best adsorption was promoted by groundwater and tertiary effluent, followed by distilled water and secondary effluent. Similar experiments, carried out at different percolation rates, indicated that a 50-day underground stay of recharged water probably suffices to eliminate viruses in the groundwater-recharged tertiary effluent. However, when viruses and sand were incubated in the presence of the surfactants sodium dodecyl sulfate, nonyl phenol, dodigen 226, or alkylbenzylsulfonate, the adsorption of the viruses was substantially diminished. Experiments in the presence of nonyl phenol seem to indicate that hydrophobic interactions are involved in the adsorption of viruses to sand. PMID:6324676

  13. A study of polyethoxylated alkylphenols by packed column supercritical fluid chromatography.

    PubMed

    Hoffman, Brian J; Taylor, Larry T

    2002-02-01

    Alkylphenol polyethoxylates (APEs) are a widely used group of nonionic surfactants in commercial production. Characterization of the composition of APE mixtures can be exploited for the determination of their most effective uses. In this study sample mixtures contain nonylphenol polyethoxylates and octylphenol polyethoxylates. The separation of individual alkylphenols by ethoxylate units is performed by supercritical fluid chromatography (SFC)-UV as well as normal-phase high-performance liquid chromatographic (HPLC)-UV employing packed columns. The stationary phase and column length are varied in the SFC setup to produce the most favorable separation conditions. Additionally, combinations of packed columns of different stationary phases are tested. The combination of a diol and a cyano column is found to produce optimal results. An advantage of using packed columns instead of capillary columns is the ability to inject large amounts of sample and thus collect eluted fractions. In this regard, fractions from SFC runs are collected and analyzed by flow injection analysis-electrospray ionization-mass spectroscopy in order to positively identify the composition of the fractions. In comparing the separation of APE mixtures by SFC and HPLC, it is found that SFC provides shorter retention times with similar resolution. In addition, less solvent waste is produced using SFC. PMID:11881706

  14. Evaluation of Packed Columns in Supercritical Extraction Processes 

    E-print Network

    Rathkamp, P. J.; Fair, J. R.; Humphrey, J. L.

    1986-01-01

    systems. In a mass transfer study at near-critical condi tions (60 atmospheres, 23 0 C), Schultz (13) built and operated a pilot plant extraction system using a 10-stage, 1.5 inch Scheibel column. The liquid' carbon dioxide solvent was used... to extract twelve model compounds (such as ethanol, ethyl butyrate, and limonene) from an aqueous feed. These compounds were used to simulate a model mixture of oranee essence. Schultz found that the feed rate had the largest effect on the percent...

  15. Pressure swing distillation for separation of homogeneous azeotropic mixtures in a mass- and heat- integrated column system: operation performance

    Microsoft Academic Search

    Jens-Uwe Repke; Andreas Klein; F. Forner; Gunter Wozny

    2004-01-01

    The separation of a homogeneous azeotropic mixture using pressure swing distillation process is deficient investigated, therefore industrial applications are limited. The dynamic behaviour of a heat- and mass-integrated pressure swing distillation column system to separate an acetonitrile\\/water mixture is analysed. Different control structures are developed and compared by using a rigorous dynamic model written in gProms®. A first validation of

  16. Liquid holdup distribution in packed columns: gamma ray tomography and CFD simulation

    Microsoft Academic Search

    Fuhe Yin; Artin Afacan; K Nandakumar; Karl T Chuang

    2002-01-01

    In the present study, the liquid (water) holdup distribution was measured in a large scale packed column (0.6 m diameter) filled with 25.4 mm metal Pall rings using noninvasive gamma ray tomography technique. Horizontal scans, at two vertical positions (400 mm apart), were made for two liquid flow rates. Three different designs of liquid distributor were used to examine the

  17. Cotransport of Pseudomonas putida and kaolinite particles through water-saturated columns packed with glass beads

    Microsoft Academic Search

    Ioanna A. Vasiliadou; Constantinos V. Chrysikopoulos

    2011-01-01

    This study is focused on Pseudomonas putida bacteria transport in porous media in the presence of suspended kaolinite clay particles. Experiments were performed with bacteria and kaolinite particles separately to determine their individual transport characteristics in water-saturated columns packed with glass beads. The results indicated that the mass recovery of bacteria and clay particles decreased as the pore water velocity

  18. New Generation of Chromatographic Packings and Columns for Determination of Biologically Active Compounds

    Microsoft Academic Search

    Bogus?aw Buszewski; Sylwia Kowalska; Katarzyna Krupczy?ska

    2005-01-01

    Analysis of biologically active substances is particularly important in the pharmaceutical and biomedical area. For separation of polar compounds or complex mixtures by normal (NP) or reversed phase liquid chromatography (RP-HPLC) and\\/or electromigration techniques, it is necessary to apply a new generation of packings and columns with strictly defined properties. It is connected to the definition of chromatographic behavior and

  19. Final Report - Advanced Hydraulic and Mass Transfer Models for Distillation Column Optimization and Design

    SciTech Connect

    Eldridge, Robert, B.

    2005-10-13

    The project successfully developed a computational fluid dynamics (CFD) based simulation of the hydrodynamics of flow in a commercial structured packing element. This result fulfilled the prime objective of the research program. The simulation utilized commercial CFD code marketed by Fluent Inc. in combination with a novel graphical interface developed by Oak Ridge National Lab. The end product will allow the design of next generation column internals without the need for extensive experimental validation and will expand the fundamental understanding of the vapor-liquid contacting process.

  20. Azeotropic distillation in a middle vessel batch column. 3: Model validation

    SciTech Connect

    Cheong, W.; Barton, P.I. [Massachusetts Inst. of Tech., Cambridge, MA (United States)] [Massachusetts Inst. of Tech., Cambridge, MA (United States)

    1999-04-01

    A dimensional time model of the middle vessel batch distillation column (MVC) is developed in the ABACUSS process modeling environment, and simulations are conducted to validate the theoretical insights developed for the operation of the MVC based on a warped time model of the MVC. The qualitative dynamics of the MVC operated in the presence of linear separation boundaries are validated via simulations conducted on the ternary azeotropic mixture of acetone, chloroform, and methanol. It is also shown via simulation that the separation results obtained from a column with significant but reasonable amounts of holdup on the trays are not significantly different from a column in which holdup in the trays is assumed to be negligible. Theoretical operating policies for separating the azeotrope of acetone and chloroform using benzene as a batch entrainer are also validated using the ABACUSS model. Finally, the authors explore the advantages and disadvantages of different feasible operating policies for separating a mixture of acetone, benzene, and chloroform completely into its constituent pure components.

  1. ?iocolloid and colloid transport through water-saturated columns packed with glass beads: Effect of gravity

    NASA Astrophysics Data System (ADS)

    Chrysikopoulos, C. V.; Syngouna, V. I.

    2013-12-01

    The role of gravitational force on biocolloid and colloid transport in water-saturated columns packed with glass beads was investigated. Transport experiments were performed with biocolloids (bacteriophages: ??174, MS2) and 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, accounting for gravity effects. The results revealed that flow direction has a significant influence on particle deposition. 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 biocolloid and colloid deposition. Schematic illustration of a packed column with up-flow velocity having orientation (-i) with respect to gravity. The gravity vector components are: g(i)= g(-z) sin? i, and g(-j)= -g(-z) cos? j. Experimental setup showing the various column arrangements: (a) horizontal, (b) diagonal, and (c) vertical.

  2. Evaluation of fructooligosaccharides separation using a fixed-bed column packed with activated charcoal.

    PubMed

    Kuhn, Raquel Cristine; Mazutti, Marcio A; Albertini, Lilian Buoro; Filho, Francisco Maugeri

    2014-05-25

    Recent studies have shown that the chromatographic separation of mixtures of saccharides may be improved by making use of activated charcoal, a promising low cost material for the separation of sugars, including fructooligosaccharides. In this work, the development of a methodology to separate fructooligosaccharides from glucose, fructose and sucrose, using a fixed bed column packed with activated charcoal is proposed. The influence of temperature, eluant concentration and step gradients were evaluated to increase the separation efficiency and fructooligosaccharide purity. The final degree of fructooligosaccharide purification and separation efficiency were about 94% and 3.03 respectively, using ethanol gradient concentration ranging from 3.5% to 15% (v/v) at 40°C. The fixed bed column packed with the activated charcoal was shown to be a promising alternative for sugar separation, mainly those rich in fructooligosaccharides, leading to solutions of acceptable degrees of purification. PMID:24583465

  3. Cubic Antimonic Acid as Column-Packing Material for Chromatographic Lithium Isotope Separation

    Microsoft Academic Search

    TAKAO OI; KAZUYUKI SHIMIZU; SHUJI TAYAMA; YOSHIO MATSUNO; MORIKAZU HOSOE

    1999-01-01

    The applicability of granular cubic antimonic acid (C-SbA) as column packing material in chromatographic lithium isotope separation was investigated. The feed solution should have the buffer capacity to promote lithium uptake, and its pH has to be kept as low as 2.25 to prevent the decomposition of the granular C-SbA in order to obtain a sharp front boundary of the

  4. Chromatographic Lithium Isotope Separation Using Cubic Antimonic Acid as Column?Packing Material

    Microsoft Academic Search

    Takao Oi; Shinko Takahashi

    2005-01-01

    Ion?exchange chromatographic lithium isotope separation was performed by using granular cubic antimonic acid as column packing material at 50°C. While the single?stage separation factor for the lithium isotopes was 1.0020, independent of the flow rate, HETP was a monotonously increasing function of flow rate both in breakthrough and reverse breakthrough experiments. After 442 cm chromatographic development, the Li atomic fraction increased

  5. Continuous metal removal from solution and industrial effluents using Spirogyra biomass-packed column reactor.

    PubMed

    Singh, Alpana; Kumar, Dhananjay; Gaur, J P

    2012-03-01

    The granules of Spirogyra neglecta biomass, diameter 0.2-0.5mm, were successfully prepared by boiling it in urea-formaldehyde mixture. Metal sorption performance of the column packed with Spirogyra granules was assessed under variable operating conditions, such as, different influent metal concentrations, bed heights and flow rates. These conditions greatly influenced the breakthrough time and volume, saturation time and volume, and the ability of the column to attain saturation after reaching the breakthrough. The experimental breakthrough curves obtained under varying experimental conditions were modeled using Bohart-Adams, Wolborska, Thomas, Yoon-Nelson and modified dose-response models. The first two models were valid only in representing the initial part of the breakthrough curves; however, the other three models were good in representing the entire breakthrough curve. The granule-packed column could be successfully used up to 6 and 9 cycles of sorption and desorption for the removal of Cu(II) and Pb(II), respectively. The column could efficiently remove different metals from real industrial effluents, and hence the test biomass (Spirogyra granules) is a good candidate for commercial application. PMID:22169159

  6. Effects of reflux ratio and feed conditions for the purification of bioethanol in a continuous distillation column

    NASA Astrophysics Data System (ADS)

    Dasan, Y. K.; Abdullah, M. A.; Bhat, A. H.

    2014-10-01

    Continuous distillation column was used for the purification of bioethanol from fermentation of molasses using Saccharomyces cerevisia. Bioethanol produced was at 8.32% (v/v) level. The efficiency of continuous distillation process was evaluated based on reflux ratio, and feed condition. The lab results were validated using COFE simulation Software. The analyses showed that both reflux ratio and feed condition had significant effects on the distillation process. Stages increased from 1.79 to 2.26 as the reflux ratio was decreased from 90% to 45% and the saturated feed produced lower mole fraction of desired product. We concluded that the lower reflux ratio with cold feed condition was suitable for higher mole fraction of top product.

  7. Distillation: Energy Savings and Other Benefits From the Use of High Efficiency Packings 

    E-print Network

    Bravo, J. L.; Fair, J. R.; Humphrey, J. L.

    1985-01-01

    Graw-Hill, NY, 1980. [3J Kuk, M. S., Chern. Eng. Progr., 2?. (5), 6B O. 2 L.-_..l....-_...J....-.l_..l-_-.l-_-.l_..l-~ (1979). I 2 4 6 10 20 40 60 100 Throughput. Uoi' Uc ? m/h [4J Meier, W., Stoeker, W. D., and Weinstein, ., Chern. Eng.Progr., J.l. (11... geometry as the packing shown in Figure 2. Vapor Out. f t tf f t t t MIxIng Cell -v- T --v- Co limn Vapor In Figure 3. Flow path arrangement in a structure~ packing. I High-efficiency random packings do not prov~.lde distinct flow channels...

  8. Recovery of dilute acetic acid through esterification in a reactive distillation column

    Microsoft Academic Search

    B. Saha; S. P. Chopade; S. M. Mahajani

    2000-01-01

    The recovery of acetic acid from its dilute aqueous solutions is a major problem in both petrochemical and fine chemical industries. The conventional methods of recovery are azeotropic distillation, simple distillation and liquid–liquid extraction. Physical separations such as distillation and extraction suffer from several drawbacks. The esterification of an aqueous solution (30%) of acetic acid with n-butanol\\/iso-amyl alcohol is a

  9. CO2 absorption in nanofluids in a randomly packed column equipped with magnetic field

    NASA Astrophysics Data System (ADS)

    Salimi, J.; Haghshenasfard, M.; Etemad, S. Gh.

    2014-10-01

    Magnetic nanofluids have been used for absorption of CO2 in a packed column in the presence of magnetic field. Adding nanoparticles into the solvent enhances mass transfer characteristics. The optimum concentrations of Fe3O4/water and NiO/water nanofluids are 0.005, and 0.01 % respectively, and the maximum enhancement of mass transfer rate in comparison with pure water is 12 and 9.5 % respectively. The magnetic field showed positive effect on the CO2 absorption performance.

  10. Characterization of column packing materials in high-performance liquid chromatography by charge-detection quadrupole ion trap mass spectrometry.

    PubMed

    Xiong, Caiqiao; Zhou, Xiaoyu; Chen, Rui; Zhang, Yiming; Peng, Wen-Ping; Nie, Zongxiu; Chang, Huan-Cheng; Liu, Huwei; Chen, Yi

    2011-07-01

    This article reports an application of charge-detection quadrupole ion trap mass spectrometry (CD-ITMS) to characterize the column packing materials in high-performance liquid chromatography (HPLC). Both the mean mass and the mass distribution of the packing materials are obtained and used to calculate the specific surface area of unbonded silica, the carbon load of the bonded silica, and their particle size distributions. The obtained specific surface areas and carbon loads are consistent with those measured independently by nitrogen sorption and elemental analysis respectively, whereas the derived size distributions show better resolution than that measured by a laser particle size analyzer. Furthermore, we evaluate the uniformity of particle size, which is the key parameter for column efficiency of the liquid chromatography by analyzing the mass distribution of the packing materials at the top and bottom of the column. A broader mass distribution, which yields decreased column efficiency, is observed for the column top because of the excessive use of the column. Our results suggest that CD-ITMS can serve as an alternative means for the characterization of the packing materials in HPLC and is potentially useful for column quality control. PMID:21612293

  11. Practical aspects of fast reversed-phase high-performance liquid chromatography using 3 ?m particle packed columns and monolithic columns in pharmaceutical development and production working under current good manufacturing practice

    Microsoft Academic Search

    Frederic Gerber; Markus Krummen; Heiko Potgeter; Alfons Roth; Christoph Siffrin; Christoph Spoendlin

    2004-01-01

    The potential and limitations of fast reversed-phase high-performance liquid chromatographic separations for assay and purity of drug substances and drug products were investigated in the pharmaceutical industry working under current good manufacturing practice using particle packed columns and monolithic columns. On particle packed columns, the pressure limitation of commercially available HPLC systems was found to be the limiting factor for

  12. Report on Qiagen Columns with Precipitation versus Packed Bed Technology for Trace Amounts of DNA

    SciTech Connect

    Wheeler, E K; Erler, A M; Seiler, A

    2008-02-05

    The assured limit of detection (LOD), where 100% of the PCR assays are successful, for the Qiagen spin column is dramatically improved when combined with an ethanol precipitation step of the eluted sample. A detailed SOP for the ethanol precipitation was delivered as a separate report. A key finding in the precipitation work was to incubate the ethanol precipitation at -20{sup o}C overnight when concentrating low copy number samples. Combining this modified ethanol precipitation with the Qiagen spin columns, the limit of assured detection was improved by 1-2 orders of magnitude, for the aliquot and assay variables used. The lower limit of detection (defined as when at least 1 assay of 1 aliquot was positive) was only improved by approximately 1 order of magnitude. The packed bed process has the potential of a 20-fold improvement in the limit of detection compared to Qiagen plus precipitation, based on a mass balance analysis for the entire DNA concentration and purification processes. Figure ES1 shows a mass balance for all the DNA processing steps. The packed bed process minimizes losses from elution, precipitation, and pipetting (aliquoting and transferring). Figure ES1 assumes that 100 copies of DNA serve as the input sample. Efficiencies for each step have been estimated based on our experiences or a worst case scenario (for example, a 50% loss was assumed for pipetting). Table ES1 summarizes the number of copies that are the input template for PCR assuming 100 copies of DNA are processed through the three options detailed in Figure ES1.Theoretically a 20-fold increase in the number of starting copies in the PCR reaction is gained when the DNA is concentrated, purified and then amplified directly on the surface of the beads in the packed bed.

  13. Direct coupling of packed column supercritical fluid chromatography to continuous corona discharge ion mobility spectrometry.

    PubMed

    Rahmanian, A; Ghaziaskar, H S; Khayamian, T

    2013-01-11

    In this study, packed column supercritical fluid chromatography (SFC) was directly coupled to a continuous corona discharge (CD) ion mobility spectrometer (IMS) with several modifications. The main advantage of the developed detector is its capability to introduce full column effluent up to 2000 mL min(-1) CO(2) gas directly into the IMS cell relative to 40 mL min(-1) CO(2) gas as a maximum tolerance, reported for the previous IMS detectors. This achievement was made possible because of using corona discharge instead of (63)Ni as an ionization source and locating the inlet and outlet of the CO(2) gas in the counter electrode of the CD in opposite direction. In addition, a heated interface was placed between back pressure regulator (BPR) and the IMS cell to heat the output of the BPR for introducing sample as the gas phase into the IMS cell. Furthermore, a make-up methanol flow was introduced between the column outlet and BPR to provide a more uniform flow through the BPR and also to prevent freezing and deposition of the analytes in the BPR. The performance of the SFC-CD-IMS was evaluated by analysis of testosterone, medroxyprogesterone, caffeine, and theophylline as test compounds and figures of merit for these compounds have been calculated. PMID:23261285

  14. Monitoring Anaerobic TCE Degradation by Evanite Cultre in Column Packed with TCE-Contaminated Soil

    NASA Astrophysics Data System (ADS)

    Ko, J.; Han, K.; Ahn, G.; Park, S.; Kim, N.; Ahn, H.; Kim, Y.

    2011-12-01

    Trichloroethylene (TCE) is a long-term common groundwater pollutant because the compound with high density is slowly released into groundwater. Physical and chemical remediation processes have been used to clean-up the contaminant, but novel remediation technology is required to overcome a low efficiency of the traditional treatment process. Many researchers focused on biological process using an anaerobic TCE degrading culture, dehalococcoides spp., but it still needs to evaluate whether the process can be applied into field scale under aerobic condition. Therefore, in this work we examined two different types (i.e., Natural attenuation and bioaugmentation) of biological remediation process in anaerobic column packed with TCE-contaminated soil. A TCE degradation by indigenous microorganisms was confirmed by monitoring TCE and the metabolites (c-DCE, VC, ETH). However, TCE was transformed and stoichiometry amount of c-DCE was produced, and VC and ETH was not detected. To test bioaugmentation of Evanite culture containing dehalococcoides spp., Evanite culture was injected into the column and TCE degradation to c-DCE, VC, ETH was monitored. We are evaluating the transport of the Evanite culture in the column by measuring TCE and VC reductases. In the result, the TCE was completely degraded to ETH using hydrogen as electron donor generate by hydrogen-production fermentation from formate.

  15. Biosorption of copper by marine algae Gelidium and algal composite material in a packed bed column.

    PubMed

    Vilar, Vítor J P; Botelho, Cidália M S; Loureiro, José M; Boaventura, Rui A R

    2008-09-01

    Marine algae Gelidium and algal composite material were investigated for the continuous removal of Cu(II) from aqueous solution in a packed bed column. The biosorption behaviour was studied during one sorption-desorption cycle of Cu(II) in the flow through column fed with 50 and 25 mg l(-1) of Cu(II) in aqueous solution, at pH 5.3, leading to a maximum uptake capacity of approximately 13 and 3 mg g(-1), respectively, for algae Gelidium and composite material. The breakthrough time decreases as the inlet copper concentration increases, for the same flow rate. The pH of the effluent decreases over the breakthrough time of copper ions, which indicates that ion exchange is one of the mechanisms involved in the biosorption process. Temperature has little influence on the metal uptake capacity and the increase of the ionic strength reduces the sorption capacity, decreasing the breakthrough time. Desorption using 0.1M HNO(3) solution was 100% effective. After two consecutive sorption-desorption cycles no changes in the uptake capacity of the composite material were observed. A mass transfer model including film and intraparticle resistances, and the equilibrium relationship, for adsorption and desorption, was successfully applied for the simulation of the biosorption column performance. PMID:18053711

  16. Permeability Change of Crystalline Silicate Mineral-Packed Bed Column by Highly Alkaline Plume

    SciTech Connect

    Hideo Usui; Yuichi Niibori; Hitoshi Mimura [Department of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Aramaki Aza Aoba 6-6-01-2, Aoba-ku, Sendai, 980-8579 (Japan); Osamu Tochiyama [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, 980-8577 (Japan)

    2007-07-01

    For the construction of the geological disposal system, the use of the cementitious material may change the permeability of the natural barrier around the repository. Cementitious materials may alter the pH of ground water to highly alkaline. Also, the potential permeability change of the natural barrier is one of the notable factors for performance assessments of geological disposal systems. In the high pH region, the solubility of silica is very high compared to that in the natural pH (around 8). Therefore, highly alkaline groundwater would dissolve and alter a part of rock surface. Usui et al. (2005) reported that the change of mineral pore structure due to chemical reaction is the key factor to consider the change of the permeability [5-6]. Moreover, such a change of the pore structure was considered to be the result of the spatial heterogeneity of chemical composition. Since such spatial heterogeneity exists also in the sedimentary rocks consisting of crystalline minerals such as quartz and feldspar, we need to examine natural rock, in order to obtain more reliable understanding about the change of permeability induced by highly alkaline groundwater (plume). In this study, silica sand as crystalline mineral was packed in the column, and the effect of dissolution induced by the highly alkaline plume on the permeability-change was examined. The silica sand particles mainly consist of SiO{sub 2} and include Al{sub 2}O{sub 3}, FeO, and K{sub 2}O. The volumetric flow rate and the pressure difference between the inlet and outlet of the column were measured, and the permeability was calculated. At the same time, the concentrations of elements in the fluid were measured by ICP-AES. The experimental result showed that permeability decreased gradually, although the silica sand was continuously dissolved in the column. The behavior of the permeability is considered to be the result from the rearrangement of the particles, or precipitation of secondary mineral. In the column test using the silica sand as packed mineral, the flow-path seems to be clogged by the rearrangement of the particles rather than the increase of the pore space between the particles. (authors)

  17. The many faces of packed column supercritical fluid chromatography--a critical review.

    PubMed

    Lesellier, Eric; West, Caroline

    2015-02-20

    Packed column sub- and supercritical fluid chromatography (SFC) is a versatile separation method: on the one hand the number of parameters acting on the quality of a separation is very large, and the effects of these parameters can be complex (and not always fully understood). But on another hand, due to numerous advantageous properties of CO2-based mobile phases, method development is a fast task. This paper is a review of the main features of SFC, focusing essentially on achiral separations. However, several fundamental aspects discussed here are also relevant to chiral SFC separations. This is not intended to be an extensive review, as the way to practice SFC has somewhat evolved with time. We rather wished to provide an expert opinion on the characteristics of the method, pointing at the sources of difficulty and displaying the wide possibilities that it offers. A large number of selected applications concerning several different areas are also presented. PMID:25604272

  18. Synthesis of porous polyaromatic column packings for GC analysis of extraterrestrial atmospheres

    NASA Technical Reports Server (NTRS)

    Woeller, F. H.; Pollock, G. E.

    1978-01-01

    The preparation of a polymer for the Pioneer-Venus Large Probe Gas Chromatograph and another polymer for gas-chromatographic analysis of the Jovian atmosphere is described. Technical-grade divinylbenzene is used as a reliable and economical source of monomer for the preparation of polymer beads. The discussion covers monomeric preparation, polymerization apparatus, first-stage polymer beads, second-stage polymer beads, amino-polymer, columns and gas-chromatographic testing instrumentation used. The polymer for the Pioneer-Venus gas chromatograph is also suitable for ammonia but not for amine analysis. However, the polymer for the analysis of the Jovian atmosphere is a chemically derivatized aromatic polymer that is suitable for amine analysis. The two-stage polymerization produces a highly efficient polymer packing clearly superior to others prepared by adjusted dilution of the aqueous-organic suspension system.

  19. Fitting adsorption isotherms to the distribution data determined using packed micro-columns for high-performance liquid chromatography.

    PubMed

    Jandera, P; Bunceková, S; Mihlbachler, K; Guiochon, G; Backovská, V; Planeta, J

    2001-08-01

    Knowing the adsorption isotherms of the components of a mixture on the chromatographic system used to separate them is necessary for a better understanding of the separation process and for the optimization of the production rate and costs in preparative high-performance liquid chromatography (HPLC). Currently, adsorption isotherms are usually measured by frontal analysis, using conventional analytical columns. Unfortunately, this approach requires relatively large quantities of pure compounds, and hence is expensive, especially in the case of pure enantiomers. In this work, we investigated the possible use of packed micro-bore and capillary HPLC columns for the determination of adsorption isotherms of benzophenone, o-cresol and phenol in reversed-phase systems and of the enantiomers of mandelic acid on a Teicoplanin chiral stationary phase. We found a reasonable agreement between the isotherm coefficients of the model compounds determined on micro-columns and on conventional analytical columns packed with the same material. Both frontal analysis and perturbation techniques could be used for this determination. The consumption of pure compounds needed to determine the isotherms decreases proportionally to the second power of the decrease in the column inner diameter, i.e. 10 times for a micro-bore column (1 mm I.D.) and 100 times for capillary columns (0.32 mm I.D.) with respect to 3.3 mm I.D. conventional columns. PMID:11519805

  20. Investigation of carryover of peptides in nano-liquid chromatography/mass spectrometry using packed and monolithic capillary columns.

    PubMed

    Dolman, Sebastiaan; Eeltink, Sebastiaan; Vaast, Axel; Pelzing, Matthias

    2013-01-01

    This article relates on reversed-phase column technology as the main cause of carryover in the LC-MS/MS analysis of proteomics samples. The separation performance and column carryover was investigated using four capillary columns with different morphologies by monitoring the remaining traces of tryptic peptides of bovine serum albumin in subsequent blank LC-MS runs. The following trend in column carryover was observed: capillary column packed with 3?m porous C18 particles?2.7?m fused-core C18 packed column>silica C18 monolith?poly(styrene-co-divinylbenzene) monolith. This is mainly related to the intrinsic properties of the different chromatographic materials, related to surface area and the presence and size of mesopores (stagnant zones where mass transfer is controlled by diffusion). Both isocratic and gradient wash steps with 2-propanol/acetonitrile mixtures were not effective to reduce column carryover. An isocratic wash step using a high acetonitrile percentage or blank gradient reduced carryover with approximately 50%. Nevertheless, it is important to note that effects of column carryover were still observed in a fifth subsequent gradient blank. Although the polymer monolith clearly outperformed the silica materials in terms of carryover, this material exhibited also the lowest loadability, which may be a disadvantage when profiling proteomics mixtures with a broad dynamic range. PMID:23261823

  1. Interaction between titanium and phosphoproteins revealed by chromatography column packed with titanium beads.

    PubMed

    Kuboki, Yoshinori; Furusawa, Toshitake; Sato, Masaaki; Sun, Yongkun; Unuma, Hidero; Fujisawa, Ryuichi; Abe, Shigeaki; Akasaka, Tsukasa; Watari, Fumio; Takita, Hiroko; Sammons, Rachel

    2012-01-01

    The biochemical mechanism behind the strong binding between titanium and living bone has not been fully elucidated, in spite of worldwide clinical application of this phenomenon. We hypothesized that one of the core mechanisms may reside in the interaction between certain proteins in the host tissues and the implanted titanium. To verify the interaction between titanium and proteins, we chose the technique of chromatography in that titanium spherical beads (45 ?m) were packed into a column to obtain a bed volume of 16×50 mm, which was eluted with phosphate buffered saline (PBS) and a straight gradient system made by using PBS and 25 mM NaOH. Fetal calf serum, albumin, lysozyme, casein, phosvitin and dentin phosphoprotein (phosphophoryn) were applied to the column. Most part of albumin and lysozyme eluted with the breakthrough peak, indicating practically no affinity to titanium. Fetal bovine serum also eluted mostly as the breakthrough peak, but distinct retained peak was observed. On the other hand, ?-casein, phosvitin and phosphophoryn exhibited a distinct retained peak separated from the breakthrough peak. We proposed that phosphate groups (phosphoserines) in the major phosphoproteins, ?-casein, phosvitin and phosphophoryn may be involved in the binding of these proteins with titanium. PMID:23023145

  2. 1.1 ?m superficially porous particles for liquid chromatography: part II: column packing and chromatographic performance.

    PubMed

    Blue, Laura E; Jorgenson, James W

    2015-02-01

    The predicted advantages of superficially porous particles over totally porous particles are decreased eddy dispersion, longitudinal diffusion, and resistance to mass transfer contributions to the theoretical plate height. While sub-2 micron superficially porous particles are commercially available, further improvements in performance are predicted by decreasing the particle diameter and decreasing the porous layer thickness. 1.1 ?m superficially porous particles with 187? pores have been synthesized using a layer-by-layer method tuned for production of smaller diameter particles. Following synthesis, these particles were packed into 30 ?m i.d. capillary columns and their chromatographic performance evaluated using electrochemical detection. Based on the initial studies, the column efficiency did not meet theory, but was similar to the commercially available products tested. It is believed that the column packing process plays a critical role in the sub-par column performance. To determine if column efficiency could be predicted by solvent-particle interactions, in-solution optical microscopy and sedimentation velocity of particles in various slurry solvents were investigated and compared to column performance. Aggregating slurry solvents, such as methanol were found to produce columns with increased efficiency. The hmin for a column packed with an acetone slurry and a methanol slurry at 3mg/mL were found to be 6.3 and 3.5, respectively. Increasing the slurry concentration to 25mg/mL further improved the efficiency, producing a column with an hmin of 2.6. These efficiency results were accurately predicted by in-solution optical microscopy. PMID:25578043

  3. A unified classification of stationary phases for packed column supercritical fluid chromatography.

    PubMed

    West, C; Lesellier, E

    2008-05-16

    The use of supercritical fluids as chromatographic mobile phases allows to obtain rapid separations with high efficiency on packed columns, which could favour the replacement of numerous HPLC methods by supercritical fluid chromatography (SFC) ones. Moreover, despite some unexpected chromatographic behaviours, general retention rules are now well understood, and mainly depend on the nature of the stationary phase. The use of polar stationary phases improves the retention of polar compounds, when C18-bonded silica favours the retention of hydrocarbonaceous compounds. In this sense, reversed-phase and normal-phase chromatography can be achieved in SFC, as in HPLC. However, these two domains are clearly separated in HPLC due to the opposite polarity of the mobile phases used for each method. In SFC, the same mobile phase can be used with both polar and non-polar stationary phases. Consequently, the need for a novel classification of stationary phases in SFC appears, allowing a unification of the classical reversed- and normal-phase domains. In this objective, the paper presents the development of a five-dimensional classification based on retention data for 94-111 solutes, using 28 commercially available columns representative of three major types of stationary phases. This classification diagram is based on a linear solvation energy relationship, on the use of solvation vectors and the calculation of similarity factors between the different chromatographic systems. This classification will be of great help in the choice of the well-suited stationary phase, either in regards of a particular separation or to improve the coupling of columns with complementary properties. PMID:18384800

  4. COAL GASIFICATION/GAS CLEANUP TEST FACILITY. VOLUME 4. A MATHEMATICAL MODEL OF THE PACKED COLUMN ACID GAS ABSORBER

    EPA Science Inventory

    The report describes a mathematical model for adiabatic operation of a packed-column absorber designed to remove acid gases from coal gasification crude product gas. It also gives results of experiments with a small pilot-scale coal gasification/gas cleaning facility designed to ...

  5. Removal of arsenic from drinking water by ferric hydroxide microcapsule-loaded alginate beads in packed adsorption column

    Microsoft Academic Search

    Priyabrata Sarkar; Priyabrata Pal; Dipankar Bhattacharyay; Suchanda Banerjee

    2010-01-01

    In this paper we have presented a unique low cost arsenic removal technique using ferric hydroxide microcapsule-loaded alginate beads (FHMCA) as an adsorbent in a continuous packed column. The microencapsulated particles of ferric hydroxide were produced in a spray dryer and subsequently coated with calcium alginate to form spherical beads of about 2 mm diameter. Batch experiments were conducted with

  6. Effects of distillation system and yeast strain on the aroma profile of Albariño (Vitis vinifera L.) grape pomace spirits.

    PubMed

    Arrieta-Garay, Y; Blanco, P; López-Vázquez, C; Rodríguez-Bencomo, J J; Pérez-Correa, J R; López, F; Orriols, I

    2014-10-29

    Orujo is a traditional alcoholic beverage produced in Galicia (northwest Spain) from distillation of grape pomace, a byproduct of the winemaking industry. In this study, the effect of the distillation system (copper charentais alembic versus packed column) and the yeast strain (native yeast L1 versus commercial yeast L2) on the chemical and sensory characteristics of orujo obtained from Albariño (Vitis vinifera L.) grape pomace has been analyzed. Principal component analysis, with two components explaining 74% of the variance, is able to clearly differentiate the distillates according to distillation system and yeast strain. Principal component 1, mainly defined by C6-C12 esters, isoamyl octanoate, and methanol, differentiates L1 from L2 distillates. In turn, principal component 2, mainly defined by linear alcohols, linalool, and 1-hexenol, differentiates alembic from packed column distillates. In addition, an aroma descriptive test reveals that the distillate obtained with a packed column from a pomace fermented with L1 presented the highest positive general impression, which is associated with the highest fruity and smallest solvent aroma scores. Moreover, chemical analysis shows that use of a packed column increases average ethanol recovery by 12%, increases the concentration of C6-C12 esters by 25%, and reduces the concentration of higher alcohols by 21%. In turn, L2 yeast obtained lower scores in the alembic distillates aroma profile. In addition, with L1, 9% higher ethanol yields were achieved, and L2 distillates contained 34%-40% more methanol than L1 distillates. PMID:25307564

  7. Continuous production of biodiesel from waste cooking oil in a reactive distillation column catalyzed by solid heteropolyacid: Optimization using response surface methodology (RSM)

    Microsoft Academic Search

    I. Noshadi; N. A. S. Amin; Richard S. Parnas

    This study aims to develop an optimal continuous process to produce fatty acid methyl esters (biodiesel) from waste cooking oil in a reactive distillation column catalyzed by a heteropolyacid, H3PW12O40·6H2O. The conventional production of biodiesel in the batch reactor has some disadvantage such as excessive alcohol demand, short catalyst life and high production cost. Reactive distillation combines reaction and separation

  8. Towards high peak capacity separations in normal pressure nanoflow liquid chromatography using meter long packed capillary columns.

    PubMed

    Han, Jing; Ye, Linquan; Xu, Lingjia; Zhou, Zhuoheng; Gao, Fan; Xiao, Zhiliang; Wang, Qiuquan; Zhang, Bo

    2014-12-10

    Single shot proteomics is a promising approach to high throughput proteomics analysis. In this strategy, long capillary columns are needed to perform long and shallow gradients to achieve high peak capacity and good peak width for informative mass spectrometric detection. Herein, we report that meter long capillary columns, packed with 5 ?m particulate material, can be facilely fabricated based on single particle fritting technology. The long columns could reliably generate high peak capacities of 800 in 10 h long gradients for protein digest separations. The operation was within the pressure range (40 MPa) of the most widely used normal pressure nanoLC systems. Due to the excellent life time (>100 injections) and inter-column performance consistency, the meter long capillary columns reported here should be of practical usefulness in single shot proteomics without the need for ultra-high pressure instrumentation. PMID:25441907

  9. Final Report - Advanced Hydraulic and Mass Transfer Models for Distillation Column Optimization and Design

    Microsoft Academic Search

    Eldridge

    2005-01-01

    The project successfully developed a computational fluid dynamics (CFD) based simulation of the hydrodynamics of flow in a commercial structured packing element. This result fulfilled the prime objective of the research program. The simulation utilized commercial CFD code marketed by Fluent Inc. in combination with a novel graphical interface developed by Oak Ridge National Lab. The end product will allow

  10. Retention mechanisms in super/subcritical fluid chromatography on packed columns.

    PubMed

    Lesellier, E

    2009-03-01

    Whereas the retention rules of achiral compounds are well defined in high-performance liquid chromatography, on the basis of the nature of the stationary phase, some difficulties appear in super/subcritical fluid chromatography on packed columns. This is mainly due to the supposed effect of volatility on retention behaviours in supercritical fluid chromatography (SFC) and to the nature of carbon dioxide, which is not polar, thus SFC is classified as a normal-phase separation technique. Moreover, additional effects are not well known and described. They are mainly related to density changes of the mobile phase or to adsorption of fluid on the stationary phase causing a modification of its surface. It is admitted that pressure or temperature modifications induce variation in the eluotropic strength of the mobile phase, but effects of flow rate or column length on retention factor changes are more surprising. Nevertheless, the retention behaviour in SFC first depends on the stationary phase nature. Working with polar stationary phases induces normal-phase retention behaviour, whereas using non-polar bonded phases induces reversed-phase retention behaviour. These rules are verified for most carbon dioxide-based mobile phases in common use (CO(2)/MeOH, CO(2)/acetonitrile or CO(2)/EtOH). Moreover, the absence of water in the mobile phase favours the interactions between the compounds and the stationary phase, compared to what occurs in hydro-organic liquids. Other stationary phases such as aromatic phases and polymers display intermediate behaviours. In this paper, all these behaviours are discussed, mainly by using log k-log k plots, which allow a simple comparison of stationary phase properties. Some examples are presented to illustrate these retention properties. PMID:18996534

  11. An extension of the multi-theta method to distillation columns and an almost band solution of the equilibrium stage problem

    E-print Network

    Gallun, Steven Eugene

    1975-01-01

    AN EXTENSION OF THE MULTI-THETA METHOD TO DISTILLATION COLUMNS AND AN ALMOST BAND SOLUTION OF THE EQUILIBRIUM STAGE PROBLEM A Thesis by STEVEN EUGENE GALLUN Submitted to the Graduate College of Texas A6M University in pa rtia I fulfillment... of the requirement for the degree of MASTER OF SCIENCE December 1975 Major Subject: Chemical Engineering AN EXTENSION OF THE MULTI-THETA METHOD TO DISTILLATION COLUMNS AND AN ALMOST BAND SOLUTION OF THE EQUILIBRIUM STAGE PROBLEM A Thesis STEVEN EUGENE GALLUN...

  12. Evaluation of a subsurface oxygenation technique using colloidal gas aphron injections into packed column reactors

    SciTech Connect

    Wills, R.A.; Coles, P.

    1991-11-01

    Bioremediation may be a remedial technology capable of decontaminating subsurface environments. The objective of this research was to evaluate the use of colloidal gas aphron (CGA) injection, which is the injection of micrometer-size air bubbles in an aqueous surfactant solution, as a subsurface oxygenation technique to create optimal growth conditions for aerobic bacteria. Along with this, the capability of CGAs to act as a soil-washing agent and free organic components from a coal tar-contaminated matrix was examined. Injection of CGAs may be useful for remediation of underground coal gasification (UCG) sites. Because of this, bacteria and solid material from a UCG site located in northeastern Wyoming were used in this research. Colloidal gas aphrons were generated and pumped through packed column reactors (PCRS) containing post-burn core materials. For comparison, PCRs containing sand were also studied. Bacteria from this site were tested for their capability to degrade phenol, a major contaminant at the UCG site, and were also used to bioaugment the PCR systems. In this study we examined: (1) the effect of CGA injection on dissolved oxygen concentrations in the PCR effluents, (2) the effect of CGA, H[sub 2]O[sub 2], and phenol injections on bacterial populations, (3) the stability and transport of CGAs over distance, and (4) CGA injection versus H[sub 2]O[sub 2] injection as an oxygenation technique.

  13. Evaluation of a subsurface oxygenation technique using colloidal gas aphron injections into packed column reactors

    SciTech Connect

    Wills, R.A.; Coles, P.

    1991-11-01

    Bioremediation may be a remedial technology capable of decontaminating subsurface environments. The objective of this research was to evaluate the use of colloidal gas aphron (CGA) injection, which is the injection of micrometer-size air bubbles in an aqueous surfactant solution, as a subsurface oxygenation technique to create optimal growth conditions for aerobic bacteria. Along with this, the capability of CGAs to act as a soil-washing agent and free organic components from a coal tar-contaminated matrix was examined. Injection of CGAs may be useful for remediation of underground coal gasification (UCG) sites. Because of this, bacteria and solid material from a UCG site located in northeastern Wyoming were used in this research. Colloidal gas aphrons were generated and pumped through packed column reactors (PCRS) containing post-burn core materials. For comparison, PCRs containing sand were also studied. Bacteria from this site were tested for their capability to degrade phenol, a major contaminant at the UCG site, and were also used to bioaugment the PCR systems. In this study we examined: (1) the effect of CGA injection on dissolved oxygen concentrations in the PCR effluents, (2) the effect of CGA, H{sub 2}O{sub 2}, and phenol injections on bacterial populations, (3) the stability and transport of CGAs over distance, and (4) CGA injection versus H{sub 2}O{sub 2} injection as an oxygenation technique.

  14. Performance characteristics and modeling of carbon dioxide absorption by amines in a packed column

    SciTech Connect

    Lin, S.H.; Shyu, C.T. (Yuan Ze Univ., Taoyuan (Taiwan, Province of China). Dept. of Chemical Engineering)

    1999-01-01

    Carbon dioxide (CO[sub 2]) is widely recognized as a major greenhouse gas contributing to global warming. To mitigate the global warming problem, removal of CO[sub 2] from the industrial flue gases is necessary. Absorption of carbon dioxide by amines in a packed column was experimentally investigated. The amines employed in the present study were the primary mono-ethanolamine (MEA) and tertiary N-methyldiethanolamine (MDEA), two very popular amines widely used in the industries for gas purification. The CO[sub 2] absorption characteristics by these two amines were experimentally examined under various operating conditions. A theoretical model was developed for describing the CO[sub 2] absorption behavior. Test data have revealed that the model predictions and the observed CO[sub 2] absorption breakthrough curves agree very well, validating the proposed model. Preliminary regeneration tests of exhausted amine solution were also conducted. The results indicated that the tertiary amine is easier to regenerate with less loss of absorption capacity than the primary one.

  15. MODELLING OF THE LIQUID DISTRIBUTION IN A TRICKLE FLOW PACKED COLUMN BASED UPON X-RAY TOMOGRAPHY IMAGES

    Microsoft Academic Search

    D. TOYE; P. MARCHOT; M. CRINE; G. LHOMME

    1999-01-01

    X-ray tomography is used to characterise the liquid distribution in a 0.6 meter diameter and 2 meter height column filled with gas-liquid absorption polypropylene packing elements (Cascade Mini-Ring 1A, Glitsch Benelux). The liquid holdup distribution is determined for Uquid flowrates ranging from 1000 l\\/h to 6000 l\\/h, that correspond to superficial velocities ranging from I0 to 6 10 m\\/s, in

  16. Pressure, temperature and density drops along supercritical fluid chromatography columns. I. Experimental results for neat carbon dioxide and columns packed with 3- and 5-micron particles.

    PubMed

    Poe, Donald P; Veit, Devon; Ranger, Megan; Kaczmarski, Krzysztof; Tarafder, Abhijit; Guiochon, Georges

    2012-08-10

    The pressure drop and temperature drop on columns packed with 3- and 5-micron particles were measured using neat CO(2) at a flow rate of 5 mL/min, at temperatures from 20°C to 100°C, and outlet pressures from 80 to 300 bar. The density drop was calculated based on the temperature and pressure at the column inlet and outlet. The columns were suspended in a circulating air bath either bare or covered with foam insulation. The results show that the pressure drop depends on the outlet pressure, the operating temperature, and the thermal environment. A temperature drop was observed for all conditions studied. The temperature drop was relatively small (less than 3°C) for combinations of low temperature and high pressure. Larger temperature drops and density drops occurred at higher temperatures and low to moderate pressures. Covering the column with thermal insulation resulted in larger temperature drops and corresponding smaller density drops. At 20°C the temperature drop was never more than a few degrees. The largest temperature drops occurred for both columns when insulated at 80°C and 80 bar, reaching a maximum value of 21°C for the 5-micron column, and 26°C for the 3-micron column. For an adiabatic column, the temperature drop depends on the pressure drop, the thermal expansion coefficient, and the density and the heat capacity of the mobile phase fluid, and can be described by a simple mathematical relationship. For a fixed operating temperature and outlet pressure, the temperature drop increases monotonically with the pressure drop. PMID:22521956

  17. Catalytic distillation structure

    DOEpatents

    Smith, Jr., Lawrence A. (Bellaire, TX)

    1984-01-01

    Catalytic distillation structure for use in reaction distillation columns, a providing reaction sites and distillation structure and consisting of a catalyst component and a resilient component intimately associated therewith. The resilient component has at least about 70 volume % open space and being present with the catalyst component in an amount such that the catalytic distillation structure consist of at least 10 volume % open space.

  18. Dynamics of reactive chromatographic columns of inert core/hollow/film coated spherical packing: an analytical solution and applications.

    PubMed

    Shams, K; Fayazbakhsh, A

    2014-11-28

    The transient behavior of reactive-diffusive fixed-bed (chromatographic columns or reactors) packed with inert core/shell core/hollow/thin film coated monodisperse spherical rigid particles is investigated. We modeled the reactive sorption system with linear mass exchange law between the flowing and the stationary phases. The coupled governing partial differential equations were integrated analytically using Laplace transformations. The analytical closed form solution involves two infinite integrals. The closed form solution was integrated numerically and the breakthrough curves of the system were studied under the influence of the system parameters. The limiting cases are discussed, a simple asymptotic closed form solution for fixed-bed desorbers with monodisperse spherical particles is obtained, and results are generalized for similar kinetics of reactive chromatographic columns (fixed-beds) for diffusion/absorption into the inert core spherical packing. Further, potential applications of the mathematical model and results in processes such as liquid vapor extraction, various forms of chromatography, reactive sorption, multifunctional reactors, process intensification, and regeneration of ion exchange columns are briefly discussed. PMID:25454133

  19. System dynamics and controller development for denitrification using a packed column bioreactor 

    E-print Network

    Boyd, Michael Edward

    1996-01-01

    is biological denitrification. For this study, two 1.5 m x 0.3 m columns were built and placed in parallel. The columns were filled with lava rock to provide sites for denitrifying bacteria to attach themselves. The system was inoculated with water from a golf...

  20. Evaluation of capillary gas chromatography for pesticide and industrial chemical residue analysis. II. Comparison of quantitative results obtained on capillary and packed columns.

    PubMed

    Fehringer, N V; Walters, S M

    1986-01-01

    Results of pesticide and industrial chemical residue determinations, using both capillary and packed column gas chromatography (GC), in 3 Food and Drug Administration (FDA) laboratories have been compiled and compared. Samples consisted of food products collected for routine residue screening by the respective laboratories. Extracts were prepared by conventional multiresidue methodology. Capillary column systems and operating conditions were selected at the discretion of each laboratory and were therefore variable, although split/splitless injectors in the split mode were used with prescribed precautions in all cases. Packed column systems were operated as specified in the FDA Pesticide Analytical Manual (PAM). Overall correlation between the 2 systems, expressed as the average ratio of packed column result to capillary column result, was 0.99 for 120 determinations in 41 samples. The higher resolving power of the capillary systems allowed quantitation of several residues that were incompletely separated and therefore unquantifiable using the packed columns. Capillary column GC with the split injection technique, used with appropriate precautions, was found to be both reliable and advantageous for regulatory determination of pesticide and industrial chemical residues in foods and feeds. PMID:3949710

  1. Transport and transformation of sulfadiazine in soil columns packed with a silty loam and a loamy sand

    NASA Astrophysics Data System (ADS)

    Unold, M.; Kasteel, R.; Groeneweg, J.; Vereecken, H.

    2009-01-01

    Concerning the transport of the veterinary antibiotic sulfadiazine (SDZ) little is known about its possible degradation during transport. Also its sorption behaviour is not yet completely understood. We investigated the transport of SDZ in soil columns with a special emphasis on the detection of transformation products in the outflow of the soil columns and on modelling of the concentration distribution in the soil columns afterwards. We used disturbed soil columns near saturation, packed with a loamy sand and a silty loam. SDZ was applied as a 0.57 mg L - 1 solution at a constant flow rate of 0.25 cm h - 1 for 68 h. Breakthrough curves (BTC) of SDZ and its transformation products 4-(2-iminopyrimidin-1(2 H)-yl)aniline and 4-hydroxy-SDZ were measured for both soils. For the silty loam we additionally measured a BTC for an unknown transformation product which we only detected in the outflow samples of this soil. After the leaching experiments the 14C-concentration was quantified in different layers of the soil columns. The transformation rates were low with mean SDZ mass fractions in the outflow samples of 95% for the loamy sand compared to 97% for the silty loam. The formation of 4-(2-iminopyrimidin-1(2 H)-yl)aniline appears to be light dependent and did probably not occur in the soils, but afterwards. In the soil columns most of the 14C was found near the soil surface. The BTCs in both soils were described well by a model with one reversible (kinetic) and one irreversible sorption site. Sorption kinetics played a more prominent role than sorption capacity. The prediction of the 14C -concentration profiles was improved by applying two empirical models other than first order to predict irreversible sorption, but also these models were not able to describe the 14C concentration profiles correctly. Irreversible sorption of sulfadiazine still is not well understood.

  2. www.pall.com 6.1 Evaluation of Chromatography Column Packing Efficiency

    E-print Network

    Lebendiker, Mario

    buffer for the resin to be evaluated 3. 5% acetone in water 4. 0.5 M NaCl in equilibration buffer 5. 6. Continue running the column with equilibration buffer at a fixed flow rate and inject 0.2 m on the Chromatogram d = peak width at half height expressed in same units as "t" L = column length (in units of cm

  3. Stability and performance of silica-based alkyl bonded-phase HPLC column packings with pH > 8 mobile phases

    SciTech Connect

    Kirkland, J.J. [Rockland Technologies, Inc., Newport, DE (United States)

    1995-12-01

    Certain HPLC separations are best performed with high pH (pH >8) mobile phases where basic compounds may not be fully protonated. However, the traditional recommendation for silica-based HPLC column packings is that they not be used with mobile phases above pH 8 because of rapid packed-bed degradation by solubility of the silica support. Studies now have shown that packings with certain types of silica supports and bonded phases can be employed successfully for routine separations with mobile phases of at least pH 9. Column packing lifetime with higher pH mobile phases also can be extended by proper choice of buffer type. Silica support solubility (and ultimate column life) is significantly influenced by the nature of both the anions and cations used in the mobile phase buffer. Even at pH 7, some alkyl bonded phase packings show poor lifetime with higher concentrations of certain buffers, especially at elevated temperatures. Column temperature and buffer concentration also greatly affect silica support solubility and ultimate column lifetime. Findings from this study should assist in the development of more rugged HPLC methods for routine applications.

  4. Protein Loading Capacity and Textural Properties of Column Packings in Reversed-Phase HPLC

    Microsoft Academic Search

    Young S. Kim; Bruce W. Sands; Jonathon L. Bass

    1987-01-01

    The relationship between the textural properties (pore size, pore volume and surface area) of reversed-phase silica gel packings for HPLC and the dynamic loading capacity of large biomolecules was studied by using silica gels manufactured by similar processes. Several silica gels whose unbonded pore diameters range from 100 to 250 A and whose pore volumes range from 1.0 to 1.4

  5. Study of dead volume measurement in packed subcritical fluid chromatography with ODS columns and carbon dioxide-modifier mobile phases.

    PubMed

    Gurdale, K; Lesellier, E; Tchapla, A

    2000-01-14

    Studies were done for providing a simple, rapid and reliable procedure of void volume measurement in packed subcritical fluid chromatography (pSubFC), with CO2-modifier mobile phases containing high modifier amounts. Methods used in RPLC with ODS columns were applied in pSubFC: gravimetric, homologous series linearisation and unretained marker injection. Results lead us to propose the method of marker injection to determine the void volume in pSubFC. Acetonitrile was chosen as the void volume marker among six tested markers. Furthermore, void volume variations vs. the modifier volume (from 5 to 45%) were studied for nine organic modifiers. The void volume variations were related both to adsorption-desorption phenomena between the mobile phase and the stationary phase and to mobile phase density changes. These variations allowed the classification of the modifiers into four groups on the basis of the molecular interactions. PMID:10670814

  6. Comparison of Packed Beds and Qiagen Columns for Recovering Trace Amounts of B. anthracis DNA from Liquid Suspensions

    SciTech Connect

    Sorensen, K; Arroyo, E; Erler, A; Christian, A T; Camp, D; Wheeler, E K

    2006-06-23

    The goal of this work was to optimize and evaluate LLNL's in-bed amplification technology to improve the level of detection for suspensions containing trace amounts of anthracis DNA. The binding/cleaning performance of the packed bed is compared to the conventional commercial approach; Qiagen column cleanup and elution, followed by detection through an ex-situ amplification process. Five liquid suspensions were spiked with B.anthracis DNA in concentration series. These suspensions were: (1) water, (2) water with EDTA, (3) dirty water from carpet extraction, (4) dirty carpet extraction with phosphate buffered saline (PBS) plus 0.1% Tween 20 plus 0.1% gelatin, and (5) a subway aerosol collected in water. Each suspension matrix was spiked with DNA and injected (in replicate) into either Qiagen Microcolumns (using the kit processing instructions) or LLNL's packed bed (using the LLNL in-bed purification and amplification protocol). The process output was assayed by quantitative polymerase chain reaction (QPCR). Table ES-1 shows the level of DNA (pg per 100 uL of input suspension) that resulted in successful amplification for all reactions (X=Y), and the level for which at least one of the reactions was successful (X>0). For each suspension and DNA concentration, there were Y QPCR assays of which X showed successful amplification. LLNL's packed bed technology outperformed Qiagen Microcolumns for all five suspensions, typically by one order of magnitude in both the limit of assured detection (all reactions positive), and the lower limit of detection (some reactions positive).

  7. Identification and quantification of gossypol in cotton by using packed micro-tips columns in combination with HPLC.

    PubMed

    Meyer, R; Vorster, S; Dubery, I A

    2004-10-01

    Self-packed micro-tip columns containing a C18-bonded silica stationary phase, based on the same principles as solid-phase extraction methods, were used to obtain gossypol and related sesquiterpenoid aldehyde-enriched fractions. The enriched metabolite fractions were then analyzed by optimized high-performance liquid chromatography (HPLC) with a C18 column (4.6 mm x 25 cm) eluted with the binary mobile phase acetonitrile-0.1% aqueous TFA solution (80:20). This method has proven to be highly reproducible. The precision and accuracy, as %RSD and %RME values, were determined to be less than 15% for the method. The minimum detection limit of gossypol was determined to be 10 ng (absolute gossypol). Absolute recovery was greater than 94% with a standard deviation of +/-3.68%. This is a simple, fast, and cost-effective method for isolation, identification, and quantification of gossypol and related secondary metabolites. Comparative analysis of gossypol content was performed on different parts of the cotton plant (seeds, stems and leaves) of two different cultivars of Gossypium hirsutum L. (Acala(1517-70) and OR19). The results indicate that the OR19 cv naturally contains higher gossypol levels than the Acala cv. It was also found that treatment of leaves with a Verticillium dahliae-derived elicitor induced production of deoxyhemigossypol rather than gossypol. PMID:15372136

  8. Measurement Reconciliation and Interpretation in Packed Distillation Column Operation Teck C. Lee and Colin S. Howat, Ph.D.

    E-print Network

    Howat, Colin S. "Chip"

    industrial scale operation, with the important exception that atypical, additional measurements can be made the tower operation and to compare the interpretation against that operation. These procedures can method applied to this tower with the vapor mass transfer coefficient being the primary adjustable

  9. Continuous adsorption of natural organic matters in a column packed with carbon nanotubes

    PubMed Central

    2013-01-01

    In the present study, continuous adsorption experiments were carried out in an adsorption column to survey the efficiency of the carbon nanotubes (CNTs) for removal of natural organic matters (NOMs) from aqueous solution. Parameters such as mass of CNTs, initial NOMs concentration were evaluated and also the breakthrough curves were obtained. Experiments performed with various initial NOMs concentration and various CNTs masses. The breakthrough period was longer at lower initial NOMs concentration. Increase of the initial NOMs concentration, expectedly, resulted in the faster saturation of the CNTs bed. The adsorption capacities for multi wall carbon nanotubes (MWCNT) and single wall carbon nanotubes (SWCNT) in highest initial NOMs concentration were 53.46 and 66.24 mg/g, respectively. The effect of amount of CNTs on breakthrough time and volume of treated water was investigated and resulted that with an increase in the mass of CNTs, breakthrough time occurs very late and the volume of treated water increased. These findings suggested that CNTs present a great potential in removal of NOMs from aqueous solutions. PMID:24499604

  10. Calcium nitrate miscible displacement at different concentrations in packed soil columns

    NASA Astrophysics Data System (ADS)

    Previatello da Silva, Livia; Alves de Oliveira, Luciano; Honorio de Miranda, Jarbas

    2015-04-01

    Studies on miscible displacement provide us with rational means to understand the important physical phenomena involved leaching in soils, fertilizers, movement of ions and other similar processes. With current environmental concerns and the need to understand the processes that govern movement of water and solutes in soil, studies are needed to allow increasing the efficiency of input use in agriculture that somehow can mitigate the impact of activities of this sector on groundwater contamination. Contamination of soil and groundwater and surface water in areas with fertilizer application and reuse of effluent is closely linked to materials chemical characteristics, and retention and transmission of water and soil solutes. Solute mobility in soil is inversely related to their adsorption to solid fraction or to environmental conditions that favor ions precipitation. Ion adsorption to soil exchange complex makes ion maintains exchange with the soil solution, providing once their retention by the solid fraction, another its availability in aqueous medium. Nitrate leaching is a physical phenomenon, favored by low energy involved in adsorption to soil particles and also by its high solubility in water. This high solubility and the weak interaction with soil matrix to allow anion follow the wetting front. Therefore, the objective was determine nitrate transport parameters in soil, through Breakthrough Curves (BTC) development under conditions of disturbed soil samples (saturated soil and steady state conditions) in columns (20.0 cm in height and 5 cm in diameter), by calcium nitrate solution application at two concentrations, 50 and 130 g m-3 NO3-, in two tropical soil types, Yellow Oxisol (S1) and Anfisol (S2). Research was carried out in laboratory. Transport parameters for both soils and nitrate concentrations were obtained by numerical fit using STANMOD software, by the inverse modelling. Results showed predominance of convective transport in S1, which had a higher Peclet number (P) at concentration 50 g m-3. There was no difference in the others parameters due to different nitrate concentrations. It was observed a higher nitrate leaching on S1.

  11. Phenol Biodegradation by Free and Immobilized Candida tropicalis RETL-Crl on Coconut Husk and Loofah Packed in Biofilter Column

    NASA Astrophysics Data System (ADS)

    Shazryenna, D.; Ruzanna, R.; Jessica, M. S.; Piakong, M. T.

    2015-04-01

    Phenols and its derivatives are environmental pollutant commonly found in many industrial effluents. It is toxic in nature and causes various health hazards. However, they are poorly removed in conventional biological processes due to their toxicity. Immobilization of microbial cells has received increasing interest in the field of waste treatment and creates opportunities in a wide range of sectors including environmental pollution control. Live cells of phenol-degrading yeast, Candida tropicalis RETL-Crl, were immobilized on coconut husk and loofah by adsorption. The immobolized particle was packed into biofilter column which used for continuous treatment of a phenol with initial phenol concentration of 3mM. Both loofah and coconut husk have similar phenol biodegradation rate of 0.0188 gL?1h?1 within 15 hours to achieve a phenol removal efficiency of 100%. However loofah have lower biomass concentration of 4.22 gL?1 compared to biomass concentration on coconut husk, 4.39 gL?1. Coconut husk contain higher biomass concentration which makes it better support material than loofah. Fibrous matrices such as loofah and coconut husk provide adequate supporting surfaces for cell adsorption, due to their high specific surface area. Therefore, coconut husk and loofah being an agricultural waste product have the potential to be used as low-cost adsorbent and support matrix for microbial culture immobilization for the removal of organic pollutant from wastewater.

  12. Adsorptive removal of fluoride from aqueous medium using a fixed bed column packed with Zr(IV) loaded dried orange juice residue.

    PubMed

    Paudyal, Hari; Pangeni, Bimala; Inoue, Katsutoshi; Kawakita, Hidetaka; Ohto, Keisuke; Alam, Shafiq

    2013-10-01

    The potential of the adsorbent prepared from DOJR marketed as cattle food in Japan was identified as an efficient and low cost adsorbent for fluoride using fixed bed column. DOJR was loaded with Zr(IV) ions to develop active adsorption sites for fluoride. Fluoride adsorption performance of column packed with Zr(IV) loaded DOJR was assessed under variable operating conditions such as Zr(IV) loading temperature, initial fluoride concentration, bed depth, initial pH, and flow rate. Breakthrough curve modeling showed that Thomas and bed depth service time (BDST) models were in good agreement with the experimental data. Application of adsorbent investigated in this study to the treatment of actual waste plating solution containing fluoride ion showed successful removal below acceptable standard in Japan using a fixed bed column, hence, Zr(IV)-DOJR can be expected to be a promising candidate for the treatment waste water containing trace amount of fluoride ion in fixed bed column. PMID:23916190

  13. Distillation: The Efficient Workhorse

    E-print Network

    Steinmeyer, D.

    ? Is the purity necessary? If steam is used as a way to drop partial pressure, why can't straight vacuum be used? If the distillation is batch, why? Would lowering column pressure ease the separation? (Often the impact on Y, in Eqn. 1, is very helpfu... DISTILLATION: THE EFFICIENT WORKHORSE Dan Steinmeyer Monsanto Company St. Louis, Missouri Distillation is inherently highly efficient: phase separation is clean it is relatively easy to build a mUltistage countercurrent device equilibrium...

  14. Evaluation of the kinetic performance of new prototype 2.1mm×100mm narrow-bore columns packed with 1.6?m superficially porous particles.

    PubMed

    Gritti, Fabrice; Shiner, Stephen J; Fairchild, Jacob N; Guiochon, Georges

    2014-03-21

    The mass transfer mechanism in three prototype narrow-bore columns (2.1mm×100mm format) packed with 1.6?m superficially porous particles was investigated using different instruments. The heights equivalent to a theoretical plate of three small molecules were measured using a mixture of acetonitrile and water as the eluent. The values reported include the contributions of longitudinal diffusion, eddy dispersion, and the solid-liquid mass transfer resistance. The bulk diffusion coefficients of the analytes were measured using the capillary method, calibrated with thiourea in pure water. The reduced longitudinal diffusion coefficient was determined from the results of a series of peak parking experiments. The solid-liquid mass transfer resistance coefficient and the intra-particle diffusivities of the analytes in the porous region of the particles were estimated from Garnett-Torquato's model of effective diffusion in dense beds packed with core-shell particles. The eddy dispersion term, mostly due to trans-column and border effects, was obtained by subtracting the longitudinal diffusion and the solid-liquid mass transfer resistance terms from the total HETP obtained from the first and second central peak moments calculated by numerical integration (Simpson's approach) after baseline correction and systematic left and right cuts of the peak profiles. The results show that the eddy dispersion controls at least 66% of the overall column HETP for small molecules beyond the optimum velocity. This work illustrates how important it is to use ultra-low dispersive very high pressure liquid chromatography (vHPLC) systems to properly measure and to practically use the high efficiencies of narrow-bore columns packed with 1.6?m core-shell particles since these columns provide intrinsic efficiencies higher than 400,000 plates per meter. PMID:24572546

  15. The Desulfurization of Fluid Catalytic Cracking Gasoline by Extractive Distillation

    Microsoft Academic Search

    H. Shen; Z. Mei; B. Shen; H. Ling

    2011-01-01

    Desulfurization of fluid catalytic cracking gasoline was investigated in a lab scale extractive distillation column. Before the extractive distillation, fluid catalytic cracking gasoline was distillated into light and heavy fractions. Then, the light fraction was desulfurized by extractive distillation using dimethylformamide as the solvent. Factors impacting the desulfurization efficiency of the extractive distillation were studied. Under optimal desulfurization conditions, distillate

  16. Gradient HPLC of samples extracted from the green microalga Botryococcus braunii using highly efficient columns packed with 2.6 ?m Kinetex-C?? core-shell particles.

    PubMed

    Gritti, Fabrice; Perdu, Marie-Agnès; Guiochon, Georges

    2012-03-16

    The analysis of the nonpolar extract of the cells of colonies of the green colonial microalgae Botryococcus braunii was performed by gradient HPLC. The growth of B. braunii was stressed by reducing its nitrogen nutrients by 90%, in order to enhance the production of nonpolar compounds. Highly efficient 4.6mm × 100mm columns packed with 2.6 ?m Kinetex-C(18) core-shell particles (Phenomenex, Torrance, CA, USA) were used. The gradient mobile phase was a mixture of acetonitrile and water (70-97%, v/v). Its initial and final compositions during the gradient elution were chosen so that the retention factors of the last eluted compound at the inlet and outlet of the column were 15 and 1, respectively. The highest peak capacity was obtained by optimizing several experimental parameters, including the injected sample volume, the flow rate, and the column length. The highest resolution was obtained by connecting one 4.6 mm × 150 mm and three 4.6mm × 100mm columns (total length 45 cm). The optimum flow rate was 1.5 mL/min, which provided the minimum plate height for the most retained compounds, the optimum inlet pressure was 930 bar and the injected volume 2 ?L. The analysis time was then 14 min for a peak capacity of 121. The trends observed for the variation of the experimental peak capacity with the flow rate and the column length are in excellent agreement with theoretical predictions. PMID:22307155

  17. Reliability of computer-assisted method transfer between several column dimensions packed with 1.3-5?m core-shell particles and between various instruments.

    PubMed

    Kormány, Róbert; Fekete, Jen?; Guillarme, Davy; Fekete, Szabolcs

    2014-06-01

    In this contribution, the possibility to automatically transfer RPLC methods between different column dimensions and instruments was evaluated using commercial modelling software. The method transfer reliability was tested with loratadine and its 7 related pharmacopeial impurities. In this study, state-of-the-art columns packed with superficially porous particles of 5, 2.6, 1.7 and 1.3?m particles were exclusively employed. A fast baseline separation of loratadine and related impurities (Rs,min=2.49) was achieved under the best analytical conditions (i.e. column of 50mm×2.1mm, 1.3?m, 10-90% ACN in 5min, T=40°C, pH=3, F=0.5ml/min). This optimal method was successfully tested on columns packed with other particle sizes, namely 1.7 and 2.6?m, to reduce pressure drop. The selectivities and retentions remained identical, while the peak widths were logically wider, leading to a reduction of peak capacity from 203 to 181 and 159 on the 1.3, 1.7 and 2.6?m particles, respectively. On the minimum, the resolution was equal to 1.54 on the 50mm×2.1mm, 2.6?m stationary phase. Next to this, the method was transferred to columns of different lengths, inner diameters and particle sizes (100mm×3mm, 2.6?m or 150mm×4.6mm, 5?m). These columns were used on other LC instruments possessing larger dwell volumes. The modelling software employed for developing the original method was able to calculate the new gradient conditions to be used. The accuracy of prediction was excellent, as the average retention time errors between predicted and observed chromatograms were -0.11% and 0.45% when transferring the method to 100mm×3mm and 150mm×4.6mm columns, respectively. This work proves the usefulness and validity of HPLC modelling software for transferring methods between different instruments, column dimensions and/or flow rates. PMID:24603352

  18. Fast gradient screening of pharmaceuticals with 5 cm long, narrow bore reversed-phase columns packed with sub-3 ?m core-shell and sub-2 ?m totally porous particles.

    PubMed

    Fekete, Szabolcs; Fekete, Jeno

    2011-04-15

    The performance of 5 cm long narrow-bore columns packed with 2.6-2.7 ?m core-shell particles and a column packed with 1.7 ?m totally porous particles was compared in very fast gradient separations of polar neutral active pharmaceutical compounds. Peak capacities as a function of flow-rate and gradient time were measured. Peak capacities around 160-170 could be achieved within 25 min with these 5 cm long columns. The highest peak capacity was obtained with the Kinetex column however it was found that as the flow-rate increases, the peak capacity of the new Poroshell-120 column is getting closer to that obtained with the Kinetex column. Considering the column permeability, peak capacity per unit time and per unit pressure was also calculated. In this comparison the advantage of sub-3 ?m core-shell particles is more significant compared to sub-2 ?m totally porous particles. Moreover it was found that the very similar sized (d(p)=2.7 ?m) and structured (?=0.63) new Poroshell-120 and the earlier introduced Ascentis Express particles showed different efficiency. Results obtained showed that the 5 cm long narrow bore columns packed with sub-3 ?m core-shell particles offer the chance of very fast and efficient gradient separations, thus these columns can be applied for fast screening measurements of routine pharmaceutical analysis such as cleaning validation. PMID:21376967

  19. Bacterial removal in flow-through columns packed with iron-manganese bimetallic oxide-coated sand

    Microsoft Academic Search

    Seong-Jik Park; Chang-Gu Lee; Song-Bae Kim; Yoon-Young Chang; Jae-Kyu Yang

    2012-01-01

    The objective of this study was to investigate the performance of iron-manganese bimetallic oxide-coated sand (IMCS) in the removal of bacteria (Escherichia coli ATCC 11105) using small-scale (length = 20 cm, inner diameter = 2.5 cm) and 30-day long-term (length = 50 cm, inner diameter = 2.5 cm) column experiments. Results indicated that the bacterial removal capacity of IMCS (qeq =

  20. Method of soil column preparation for the evaluation of viral transport.

    PubMed Central

    Funderburg, S W; Moore, B E; Sorber, C A; Sagik, B P

    1979-01-01

    A method for packing soil columns to investigate viral transport phenomena is described. The columns were 10 cm in diameter and ranged from 33 to 100 cm in length. Field conditions of the soil, including bulk density and profile, were reproduced in columns. Ionic gradients resulting from sequential applications of wastewater and distilled water affected the movement of poliovirus I (Chat) through soil. Compared with 33-cm- and 66-cm-length columns, lower concentrations of infectious virions were observed in the percolates from 100-cm soil columns. These results may be attributed to the greater pore volume in the longer columns (the greater volume of soil contained in these columns), whereas the volume of liquid applied was constant for all columns. PMID:225992

  1. Removal of Cu(II) and Cr(VI) ions from aqueous solution using chelating fiber packed column: equilibrium and kinetic studies.

    PubMed

    Ko, Young Gun; Chun, Yong Jin; Kim, Choong Hyun; Choi, Ung Su

    2011-10-30

    Herein, we demonstrate the adsorption process system with the diethylenetriamne coupled polyacrylonitrile fiber for the removal of Cu(II) and Cr(VI) ions in the aqueous solution. The synthesized chelating fiber showed a high adsorption capacity of 11.4 mequiv/g. Interestingly, the crystal growth of copper ions on the chelating fiber was observed during the adsorption process. The chelating fiber packed column showed the high performance of the removal of Cu(II) in the aqueous solution due to the distinct characteristic of the crystal growth of metal ions on the chelating fiber. After Cu(II) adsorption on the chelating fiber, the color of the fiber changed to light blue from yellow. The isotherm parameter n of 1.991 was obtained with Freundlich isotherm model for the adsorption equilibrium study which indicates that Cu(II) adsorption on the chelating fiber is very favorable due to n>1. The pseudo-first-order and pseudo-second-order model equations were used for the kinetic study. PMID:21871730

  2. Column test-rig facility for column scanning studies

    NASA Astrophysics Data System (ADS)

    Zain, Rasif M.; Roslan, Y.

    2009-12-01

    Distillation columns are considered as one of the most critical components in oil and gas plants. The plant performance depends on the ability of these columns to function as intended. Defective columns may lead to serious consequences to the plant operation, and hence the quality of product. In order to perform any inspection techniques to distillation column for NDT practitioner, the best facility was designed when the adjustable defeats of distillation column test rig has been developed. The paper discussed the development and the function of this facility.

  3. Column test-rig facility for column scanning studies

    NASA Astrophysics Data System (ADS)

    Zain, Rasif M.; Roslan, Y.

    2010-03-01

    Distillation columns are considered as one of the most critical components in oil and gas plants. The plant performance depends on the ability of these columns to function as intended. Defective columns may lead to serious consequences to the plant operation, and hence the quality of product. In order to perform any inspection techniques to distillation column for NDT practitioner, the best facility was designed when the adjustable defeats of distillation column test rig has been developed. The paper discussed the development and the function of this facility.

  4. Design of processes with reactive distillation line diagrams

    Microsoft Academic Search

    B. Bessling; G. Schembecker; K. H. Simmrock

    1997-01-01

    On the basis of the transformation of concentration coordinates, the concept of reactive distillation lines is developed. It is applied to study the feasibility of a reactive distillation with an equilibrium reaction on all trays of a distillation column. The singular points in the distillation line diagrams are characterized in terms of nodes and saddles. Depending on the characterization of

  5. An extension of the multi-theta method to distillation columns and an almost band solution of the equilibrium stage problem 

    E-print Network

    Gallun, Steven Eugene

    1975-01-01

    in the modern Chemical Industry. Iv ACKNOWLEDGMENTS The financial support provided by Texas Eastman Company, Dow Chemica 1 USA, Exxon USA Foundation, Alcoa Foundation, and the Texas Engineering Experiment Station is greatly appreciated, TABLE OF CONTENTS...) and Lewis (1909) were among the first to analyze distillation processes with any degree of mathematical rigor. By the middle 1930's methods proposed by Lewis and Matheson (1932) and Thiele and Geddes (1933) were being used to attempt the design...

  6. Energy Use in Distillation Operation: Nonlinear Economic Effects 

    E-print Network

    White, D. C.

    2010-01-01

    important. For many distillation columns there is a tradeoff in operation between energy usage and product recovery and setting the proper usage target involves a calculation of the economic tradeoff between these two factors. However, distillation is a non...

  7. Solar Distillation

    Microsoft Academic Search

    Rahul Dev; Gopal Nath Tiwari

    \\u000a “Solar distillation” is a technology for producing potable water from brackish and underground water of low-quality at low\\u000a cost. It can reduce water-scarcity problems together with other water purification technologies. Solar distillation is analogous\\u000a to natural hydrological cycle. It uses an apparatus called a solar still in which water is evaporated using solar energy,\\u000a a form of renewable energy, and

  8. Active Constraint Regions for Optimal Operation of Distillation Magnus G. Jacobsen and Sigurd Skogestad*

    E-print Network

    Skogestad, Sigurd

    Active Constraint Regions for Optimal Operation of Distillation Columns Magnus G. Jacobsen, NTNU, N-7491, Trondheim, Norway ABSTRACT: When designing the control structure of distillation columns presented in an earlier paper, to find how the active constraints for distillation columns change

  9. Method for packing chromatographic beds

    DOEpatents

    Freeman, David H. (Potomac, MD); Angeles, Rosalie M. (Germantown, MD); Keller, Suzanne (Rockville, MD)

    1991-01-01

    Column chromatography beds are packed through the application of static force. A slurry of the chromatography bed material and a non-viscous liquid is filled into the column plugged at one end, and allowed to settle. The column is transferred to a centrifuge, and centrifuged for a brief period of time to achieve a predetermined packing level, at a range generally of 100-5,000 gravities. Thereafter, the plug is removed, other fixtures may be secured, and the liquid is allowed to flow out through the bed. This results in an evenly packed bed, with no channeling or preferential flow characteristics.

  10. Intermediate Vapor Expansion Distillation and Nested Enrichment Cascade Distillation 

    E-print Network

    Erickson, D. C.

    1986-01-01

    and venting the reject heat to ambient. When efficiency is defined as the ratio of two work terms, more representative efficiencies in the 10 to 45% range are usually obtair.ecJ. Figure 1 is a plot of the ideal separation work for a binary mixture (King..., 1981) and the corresponding separation work required by a simple distillation column at minimum reflux (Benedict, 1947), all as a IDEAL SIMPLE DISTILLATION l.~--------- --J O. 0.8 IDEAL SEPARATION 0.7 : 0.5 ll.-i 0.3 n.:! 0.1 o 0.1 O...

  11. SIMULATION BASED OPTIMIZATION OF A DIABATIC DISTILLATION Edward Steven Jimenez and Peter Salamon

    E-print Network

    Salamon, Peter

    SIMULATION BASED OPTIMIZATION OF A DIABATIC DISTILLATION COLUMN Edward Steven Jimenez and Peter distillation is a separation process in which heat is transferred inside the column as opposed to classical of this technology on the chemical and process industry is enormous since distillation is the single largest energy

  12. Steady-state simulation of a TSTA column by means of a mass-transfer model

    SciTech Connect

    Latge, C. [French Atomic Energy Commission, Saint-Paul-lez-Durance (France); Sherman, R.S. [Los Alamos National Lab., NM (United States); Sere-Peyrigain, P. [PROSIM S.A., Toulouse (France)

    1995-10-01

    The simulation of the units for hydrogen isotope separation by cryogenic distillation with packed columns can be carried out with a very efficient tool, based on a non equilibrium model [1]. This new approach enables a better representation of the physical phenomena involved in the columns to be obtained and consequently, better accuracy for the tritium inventory in the whole process. At the TSTA facility, one of main systems is the Isotope Separation System (ISS), fitted with an on-line laser Raman spectroscopy system: it allows to obtain very accurate composition profiles in the columns, rapidly and safely. Using experimental data, provided by TSTA, CEA, associated with PROSIM S.A., have carried out calculations on column 1. This study clearly demonstrates: the high efficiency of the experimental device; the good accuracy of the results in comparison with experimental data (composition profiles); and the efficacy of the method for design activities. 7 refs., 3 figs., 3 tabs.

  13. The rationale for the optimum efficiency of columns packed with new 1.9?m fully porous Titan-C18 particles-a detailed investigation of the intra-particle diffusivity.

    PubMed

    Gritti, Fabrice; Guiochon, Georges

    2014-08-15

    In a previous report, it was reported that columns packed with fully porous 1.9?m Titan-C18 particles provided a minimum reduced plate height as small as 1.7 for the most retained compound (n-octanophenone) under RPLC conditions. These particles are characterized by a relatively narrow size distribution with a relative standard deviation (RSD) of only 10%. A column packed with classical 5?m Symmetry-C18 particles, used as a reference RPLC column, generated a minimum reduced plate height of 2.1 for the same retained compound. This work demonstrates that this was due to an unusually low intra-particle diffusivity across these particles, which leads to a small longitudinal diffusion coefficient along the column. The demonstration is based on the combination of accurate measurements of the height equivalent to a theoretical plate (HETP), inverse size exclusion chromatography (ISEC), peak parking (PP), and minor disturbance method (MDM) experiments. The experimental results show that the reduced eddy dispersion HETP term (A=0.8 for a reduced velocity of 5), the internal particle porosity (?p=0.35), and the enrichment of acetonitrile in the pore volume (75% acetonitrile in the bulk, 85% inside the mesoporous volume) are identical on both the Titan-C18 and Symmetry-C18 columns. The difference between the internal structures of these two brands of RPLC-C18 fully porous particles lies in the values of the internal obstruction factor ?p, which is 0.42 for the Symmetry-C18 but only 0.26 for the Titan-C18 particles. This is in part related to the diffusion hindrance due to the small average pore size of the Titan-C18 particles, around 59? versus 77? for Symmetry-C18 particles. A simple model of constriction along diffusion paths having the shape of a truncated cone suggests that the width of the pore size distribution (RSD of 30% and 20% for Titan-C18 and Symmetry-C18 particles) is mostly responsible for the difference in their obstruction factors. PMID:24969087

  14. Catalytic Distillation 

    E-print Network

    Smith, L. A., Jr.; Hearn, D.; Wynegar, D. P.

    1984-01-01

    is continously removed by distillation as it is formed, thus substantially negating the reverse reaction. Also HeOR can be added directly to the reaction zone at a point where the isobutylene concentration is the lowest which also helps drive... the equilibrium forward toward HTBE formation. The net effect is equivalent to "multiple equilibrium stages" and almost total conversion of isobutylene to HTBE. Another possibili ty is to hold the IB in molar excess of HeOH and react HeOH to near extinction...

  15. Intelligent fuzzy supervisory control for distillation columns 

    E-print Network

    Santhanam, Srinivasan

    1993-01-01

    for dynamically adapting the models to achieve tight composition control. Simple control techniques do not exist for model adaptation in MIMO systems. This thesis will outline a fuzzy supervisory controller based on fuzzy logic and show that control performance...

  16. Comparison of a Multipore Column with a Mixed-Bed Column for Size Exclusion Chromatography

    Microsoft Academic Search

    M. Nagata; T. Kato; H. Furutani

    1998-01-01

    A new type of column packed with polystyrene gels which have a broad pore size distribution in a particle (henceforth referred to as the multipore column) was developed, and its performance was compared with the so-called linear column (henceforth referred to as the mixed-bed column). The chromatogram of the epoxy resin (Epikote 1009) on the multipore column showed a monomodal

  17. Determination of chromium(VI) and lead in water samples by on-line sorption preconcentration coupled with flame atomic absorption spectrometry using a PCTFE-beads packed column.

    PubMed

    Anthemidis, Aristidis N; Koussoroplis, Salome-Juliette V

    2007-03-15

    A new time-based flow injection on-line solid phase extraction method for chromium(VI) and lead determination using flame atomic absorption spectrometry was developed. The use of hydrophobic poly-chlorotrifluoroethylene (PCTFE)-beads as absorbent in on-line preconcentration system was evaluated. Effective formation of ammonium pyrrolidine dithiocarbamate complexes and subsequently retention in PCTFE packed column, was achieved in pH range 1.0-1.6 and 1.5-3.2 for Cr(VI) and Pb(II) ions, respectively. The sorbed analyte was efficiently eluted with isobutyl-methyl-ketone for on-line FAAS determination. The proposed packing material exhibited excellent chemical and mechanical resistance, fast kinetics for adsorption of Cr(VI) and Pb(II) permitting the use of high sample flow rates at least up to 15mLmin(-1) without loss of retention efficiency. For a preconcentration time of 90s, the sample frequency was 30h(-1), the enhancement factor was 94 and 220, the detection limit was 0.4 and 1.2mugL(-1), while the precision (R.S.D.) was 1.8% (at 5mugL(-1)) and 2.1% (at 30mugL(-1)) for chromium(VI) and lead, respectively. The applicability and the accuracy of the developed method were estimated by the analysis spiked water samples and certified reference material NIST-CRM 1643d (Trace elements in water) and NIST-SRM 2109 (chromium(VI) speciation in water). PMID:19071515

  18. Photocatalytic degradation of recalcitrant organic pollutants in water using a novel cylindrical multi-column photoreactor packed with TiO2-coated silica gel beads.

    PubMed

    Li, Dawei; Zhu, Qi; Han, Chengjie; Yang, Yingnan; Jiang, Weizhong; Zhang, Zhenya

    2015-03-21

    A novel cylindrical multi-column photocatalytic reactor (CMCPR) has been developed and successfully applied for the degradation of methyl orange (MO), amoxicillin (AMX) and 3-chlorophenol (3-CP) in water. Due to its higher adsorption capacity and simpler molecular structure, 3-CP compared with MO and AMX obtained the highest photodegradation (100%) and mineralization (78.1%) after 300-min photocatalytic reaction. Electrical energy consumption for photocatalytic degradation of MO, AMX and 3-CP using CMCPR was 5.79×10(4), 7.31×10(4) and 2.52×10(4) kW h m(-3) order(-1), respectively, which were less than one-thousand of those by reported photoreactors. The higher flow rate (15 mL min(-1)), lower initial concentration (5 mg L(-1)) and acidic condition (pH 3) were more favorable for the photocatalytic degradation of MO using CMCPR. Five repetitive operations of CMCPR achieved more than 97.0% photodegradation of MO in each cycle and gave a relative standard deviation of 0.72%. In comparison with reported slurry and thin-film photoreactors, CMCPR exhibited higher photocatalytic efficiency, lower energy consumption and better repetitive operation performance for the degradation of MO, AMX and 3-CP in water. The results demonstrated the feasibility of utilizing CMCPR for the degradation of recalcitrant organic pollutants in water. PMID:25528240

  19. DYNAMIC MODELING AND CONTROL OF REACTIVE DISTILLATION FOR HYDROGENATION OF BENZENE 

    E-print Network

    Aluko, Obanifemi

    2010-01-16

    This work presents a modeling and control study of a reactive distillation column used for hydrogenation of benzene. A steady state and a dynamic model have been developed to investigate control structures for the column. The most important aspects...

  20. Computational performance of aggregated distillation models

    Microsoft Academic Search

    Andreas Linhart; Sigurd Skogestad

    2009-01-01

    Compartmental and aggregated modeling is used to derive low-order (reduced) dynamic models from detailed models of staged processes. In this study, the aggregated modeling method of (Lévine, J., & Rou- chon, P. (1991). Quality control of binary distillation columns via nonlinear aggregated models. Automatica, 27, 463) is revised with the objective of deriving computationally efficient models for real-time control and

  1. Pack Saddle

    USGS Multimedia Gallery

    This is a pack saddle used by Arnold Hague in the late 1800s. The wooden saddle has leather straps and a cinch used for the animal's comfort when carrying especially large loads. Pack saddles could be used to carry panniers or other large objects. Object ID: USGS-000014...

  2. Ammonia removal from coal dry distillation wastewater

    Microsoft Academic Search

    Guanghua Wang; Fanjie Gong; Wenbing Li; Yunzhou Lu; Mingdong Sun; Tiejun Liu; Yuhe Liang; Xiaoyuan Li; Zengqiang Huang

    2011-01-01

    the article used coke oven gas as desorption agent, pilot-scale packed tower as desorption equipment, removed ammonia from wastewater produced by coal dry distillation process. Gas stripping method is a new technology for ammonia removal. Through experiments conducted in the coking plant, when the temperature of wastewater T=85°C, pH=1l.5, the ratio of liquid and gas volume n=550:1 and the addition

  3. Microwave accelerated steam distillation of essential oil from lavender: A rapid, clean and environmentally friendly approach

    Microsoft Academic Search

    F. Chemat; M. E. Lucchesi; J. Smadja; L. Favretto; G. Colnaghi; F. Visinoni

    2006-01-01

    A new process design and operation for microwave accelerated steam distillation (MASD) of essential oils was developed. A packed bed of lavender flowers (Lavandula angustifolia Mill., Lamiaceae) sits above the steam source generated by microwave heating. Only steam passes through it without the boiling water mixing with vegetable raw material, as is the case in hydro-distillation. MASD has been compared

  4. Contact structure for use in catalytic distillation

    DOEpatents

    Jones, Jr., Edward M. (Friendswood, TX)

    1984-01-01

    A method for conducting catalytic chemical reactions and fractionation of the reaction mixture comprising feeding reactants into a distillation column reactor contracting said reactant in liquid phase with a fixed bed catalyst in the form of a contact catalyst structure consisting of closed porous containers containing the catatlyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column.

  5. Contact structure for use in catalytic distillation

    DOEpatents

    Jones, Jr., Edward M. (Friendswood, TX)

    1985-01-01

    A method and apparatus for conducting catalytic chemical reactions and fractionation of the reaction mixture, comprising and feeding reactants into a distillation column reactor contracting said reactant in a liquid phase with a fixed bed catalyst in the form of a contact catalyst structure, consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column.

  6. Distill, Distill_human Distill: protein structure prediction by Machine Learning

    E-print Network

    Pollastri, Gianluca

    Distill, Distill_human Distill: protein structure prediction by Machine Learning C. Mirabello1, G.pollastri@ucd.ie Distill has two main components: a set of predictors of protein features based on machine learning" of PDB structures suggested by our fold recognition algorithm. The only difference between Distill

  7. Heat pumps in distillation

    Microsoft Academic Search

    1976-01-01

    The methods used and results obtained in evaluating the economics of substituting heat pumps for conventional distillation process design are presented. From this study it was concluded that: heat pumps have extensive applicability to distillation whenever direct refrigeration or chilled water are required for condensation; heat pumps have limited, but very real ranges of applicability when reboiler temperatures are above

  8. Energy Recovery in Industrial Distillation Processes 

    E-print Network

    Paul, D. B.

    1983-01-01

    on of ~ seven-stage horizontally split centrifugal compressor manufactured by General Electric Company*. Pressure ratios greater than 10:1 ar~ possible with this design. Each compression stage of the mUltistag~ centri fugal compressor consi sts of a shaft.... Figure 4 shows the distillation column employing multi stage vapor recompression. The centrifugal compressor is a five stage General Electric Company design employing a horizontally split casing. Compression of the 163,000 lb/hr inlet from 18 psia...

  9. Deterpenation of Brazilian orange peel oil by vacuum distillation

    Microsoft Academic Search

    Giane R. Stuart; Daíse Lopes; J. Vladimir Oliveira

    2001-01-01

    The deterpenation of orange peel oil in most industries is accomplished by vacuum distillation, but surprisingly little information\\u000a on this matter can be found in the open literature. This work reports recent results on orange peel oil deterpenation carried\\u000a out in an automatic vacuum distillation column operated in the semibatch mode at the temperatures of 50, 65, and 80C, at

  10. Valve Packing

    NASA Technical Reports Server (NTRS)

    1992-01-01

    "S Glass" yarn was originally developed by NASA for high temperature space and aeronautical applications. When John Crane, Inc. required material that would withstand temperatures higher than 1,200 degrees Fahrenheit, they contacted Owens-Corning, which had developed a number of applications for the material. John Crane combines the yarn with other components to make Style 287-I packing. The product can be used in chemical processing operations, nuclear power stations, petroleum products, etc. Advantages include increased service life and reduced maintenance costs.

  11. Experimental and Numerical Investigation of Two Dimensional CO2 Adsorption/Desorption in Packed Sorption Beds under Non-Ideal Flows

    NASA Technical Reports Server (NTRS)

    Mohamadinejad, H.; Knox, J. C.; Smith, J. E.; Croomes, Scott (Technical Monitor)

    2001-01-01

    The experimental results of CO2 adsorption and desorption in a packed column indicated that the concentration wave front at the center of the packed column differs from those which are close to the wall of column filled with adsorbent material even though the ratio of column diameter to the particle size is greater than 20. The comparison of the experimental results with one dimensional model of packed column shows that in order to simulate the average breakthrough in a packed column a two dimensional (radial and axial) model of packed column is needed. In this paper the mathematical model of a non-slip flow through a packed column with 2 inches in diameter and 18 inches in length filled with 5A zeolite pellets is presented. The comparison of experimental results of CO2 absorption and desorption for the mixed and central breakthrough of the packed column with numerical results is also presented.

  12. Winogradsky Columns

    NSDL National Science Digital Library

    John Lennox

    This is an exercise about Winogradsky Columns with emphasis placed on the formation and properties of microbial biofilms. It includes background reference material, a field/lab exercise, and several applications. Applications include methods for sampling column layers and a description of how to measure the electro-chemical gradient that develops within the column. Scientific illustrations and images are included as visual references.

  13. Heterogeneous Batch Distillation Processes for Waste Solvent Recovery in Pharmaceutical Industry

    Microsoft Academic Search

    Ivonne Rodriguez-Donis; Vincent Gerbaud; Alien Arias-Barreto; Xavier Joulia

    2009-01-01

    A summary about our experiences in the introduction of heterogeneous entrainers in azeotropic and extractive batch distillation is presented in this work. Essential advantages of the application of heterogeneous entrainers are showed by rigorous simulation and experimental verification in a bench batch distillation column for separating several azeotropic mixtures such as acetonitrile — water, n hexane — ethyl acetate and

  14. Reactive Distillation and Air Stripping Processes for Water Recycling and Trace Contaminant Control

    NASA Technical Reports Server (NTRS)

    Boul, Peter J.; Lange, Kevin E.; Conger, Bruce; Anderson, Molly

    2009-01-01

    Reactive distillation designs are considered to reduce the presence of volatile organic compounds in the purified water. Reactive distillation integrates a reactor with a distillation column. A review of the literature in this field has revealed a variety of functional reactive columns in industry. Wastewater may be purified by a combination of a reactor and a distiller (e.g., the EWRS or VPCAR concepts) or, in principle, through a design which integrates the reactor with the distiller. A review of the literature in reactive distillation has identified some different designs in such combinations of reactor and distiller. An evaluation of reactive distillation and reactive air stripping is presented with regards to the reduction of volatile organic compounds in the contaminated water and air. Among the methods presented, an architecture is presented for the evaluation of the simultaneous oxidation of organics in air and water. These and other designs are presented in light of potential improvements in power consumptions and air and water purities for architectures which include catalytic activity integrated into the water processor. In particular, catalytic oxidation of organics may be useful as a tool to remove contaminants that more traditional distillation and/or air stripping columns may not remove. A review of the current leading edge at the commercial level and at the research frontier in catalytically active materials is presented. Themes and directions from the engineering developments in catalyst design are presented conceptually in light of developments in the nanoscale chemistry of a variety of catalyst materials.

  15. Distillation: Present Status and Future Directions 

    E-print Network

    Fair, J. R.; Humphrey, J. L.

    1984-01-01

    -ambitious listing project, covered in a single volume, is that of Hirata, Ohe, and Naghama [17]. In summary, current work is concentrated on the compilation of VLE and the development of estimating parameters for the UNIFAC predictive method. Both... idea. *Sulzer packing, formed from wire mesh in a special corrugated arrangement (Figure 4), has been tested hy FRI in a 40-inch column in Switzerland. The results are available from the vendor [34J. To summarize the needs for research...

  16. Influence of distillation system, oak wood type, and aging time on volatile compounds of cider brandy.

    PubMed

    Madrera, Roberto Rodríguez; Gomis, Domingo Blanco; Alonso, Juan J Mangas

    2003-09-10

    A study of the influence of distillation system, oak wood type, and aging time on volatile compounds of cider brandy was carried out. Acetaldehyde and acetaldehyde diethyl acetal were influenced by distillation technology, oak wood type, and maturation time. The majority ester, ethyl ethanoate, increased during aging, the highest level of this ester being detected in spirits distilled by double distillation. The alcohols of higher molecular weight were better recovered in the rectification column than in the double distillation system. Ethanoate esters decreased throughout aging of the spirits, and their degradation velocity was lower in distillates obtained from double distillation. Fatty acids and their ethyl esters presented the opposite evolution during aging, detecting an increase in ethyl esters and a decrease in their corresponding fatty acids. An increase of 1,1,3-triethoxypropane was detected during aging. French oak contributes the trans isomer of beta-methyl-gamma-octalactone and American oak contributes the cis isomer. PMID:12952423

  17. Energy efficient distillation apparatus

    SciTech Connect

    Melton, J.D.

    1982-08-17

    An energy efficient distillation method is provided which is particularly adapted for use on a dairy farm, and which comprises a distilland evaporating receptacle, a distillate condensing receptacle, and a conduit interconnecting the evaporating receptacle and the condensing receptacle. A vacuum pump is provided for drawing a partial vacuum within the evaporating receptacle, and a vapor compression refrigeration system is provided which includes condenser coils disposed to heat and vaporize the distilland while it is within the evaporating receptacle, and evaporator coils for cooling and condensing the vaporized distilland in the condensing receptacle. A cooling distribution system is also provided whereby a variable portion of the cooling potential of the refrigeration system may be selectively directed to each of the condensing receptacle, a distillate receiver tank, or to a bulk milk container as utilized on a dairy farm or the like.

  18. Efficient distillation beyond qubits

    SciTech Connect

    Vollbrecht, Karl Gerd H.; Wolf, Michael M. [Institute for Mathematical Physics, TU Braunschweig, Braunschweig (Germany)

    2003-01-01

    We provide generalizations of known two-qubit entanglement distillation protocols for arbitrary Hilbert space dimensions. The protocols, which are analogs of the hashing and breeding procedures, are adapted to bipartite quantum states that are diagonal in a basis of maximally entangled states. We show that the obtained rates are optimal, and thus equal to the distillable entanglement, for a (d-1)-parameter family of rank deficient states. Methods to improve the rates for other states are discussed. In particular, for isotropic states it is shown that the rate can be improved such that it approaches the relative entropy of entanglement in the limit of large dimensions.

  19. Solution of systems of columns with energy exchange between recycle streams 

    E-print Network

    Haas, Joe Ray

    1980-01-01

    ILLUSTRATIVE EXAMPLES FOR THE SOLUTION OF PROBLEMS INVOLVING SINGLE COLUMNS 1QS Distillation Columns Absorbers 108 125 Application of the Capital Theta Such that Each Stage is Treated as a Column 147 CONCLUSIONS 154 Systems of Columns with Energy... Recycle Between Columns Single Column Convergence Methods NOTATIONS LITERAlURE CITED 154 155 156 160 Page APPENDIX 166 VITA 178 LIST OF TABLES Table Page 1. Specifications for Examples 1 and 2 2. Initial Values of Variables for Examples 1...

  20. Distilling Abstract Machines Beniamino Accattoli

    E-print Network

    Mazza, Damiano

    Distilling Abstract Machines Beniamino Accattoli Carnegie Mellon University & Universit`a di rather distills them: some transitions are simulated while others vanish, as they map to a notion of structural congruence. The distillation process unveils that abstract machines in fact implement weak linear

  1. Well packing system

    Microsoft Academic Search

    Drnevich

    1990-01-01

    This patent describes a packing structure and method of packing which can be used in the wellbore of injection wells for the recovery of heavy oils, shale oils, and tars, and in well shafts for in-situ coal gasification. The packing can also be used in the wellbore of gas and light oil production wells. The packing is used to provide

  2. Method for making a non-extractable stationary phase of polymer within a capillary column

    DOEpatents

    Springston, S.R.

    1990-10-30

    A method is described for coating interior capillary column surfaces, or packing material of a packed column, used for gas chromatography, with a stationary polymer phase that is cross-linked by exposing it to a low-temperature plasma that is uniformly distributed over the column or packing material for a predetermined period of time to effect the desired degree of cross-linking of the coating. 7 figs.

  3. A startup model for simulation of batch distillation starting from a cold state

    Microsoft Academic Search

    Lin Wang; Pu Li; Günter Wozny; Shuqing Wang

    2003-01-01

    Batch distillation columns are frequently started up with a different initial reboiler charge. A proper initial state is required for simulation and optimization of such processes, but it has been a non-trivial task to obtain it. In this work, a model to express startup behaviors of batch columns starting from an empty cold state is proposed to address this issue.

  4. An Analogy between Fractional Distillation and Separating Physically Fit and Physically Less Fit Persons

    NASA Astrophysics Data System (ADS)

    Mukesh, Doble

    2001-02-01

    Separating two liquids in a fractional distillation column on the basis of their difference in boiling points is analogous to separating a group of people on the basis of their physical fitness by making them climb a flight of stairs. Several aspects of this unit operation such as column height, flooding, and reflux ratio are explained with the help of this analogy.

  5. Trajan's Column

    NSDL National Science Digital Library

    This Website, from McMaster University, uses the combined skills of artists, writers, programmers, and Web designers to create a resource for the study of Trajan's column, a Roman architectural monument. This 100-foot marble column, built during the reign of Emperor Trajan, 98-117 AD, is topped with a gilded statue of Trajan and decorated with carvings recounting Trajan's rule, primarily the Dacian Wars and his building projects. The heart of the Website is the database of 500 slides of the carvings; indexes allow users to view the slides in thematic groupings such as images of sides of the column, groups organized by subject keywords, or carvings made with specific tools. Cartoons or drawings of the column help to contextualize the details found in the slides, and essays provide more information on its design, construction, and preservation.

  6. Precise laboratory fractional distillation of fatty acid esters

    Microsoft Academic Search

    Frank A. Norris; David E. Terry

    1945-01-01

    Summary  Important factors in the construction and operation of laboratory fractionating columns are discussed. These include column\\u000a diameter and insulation, packing, pressure drop, effect of reflux and molecular weight on fractionating efficiency, reflux\\u000a regulation, choice of operating pressure, constant pressure maintenance, and accurate measurement of pressure. Accurate boiling\\u000a points in the 1–20 mm. range are reported for the first time for

  7. A comparison study of in-column and on-column detection for electrochromatography.

    PubMed

    Zhang, Qier; Xu, Lingjia; Zhou, Zhuoheng; Yang, Lijun; Wang, Qiuquan; Zhang, Bo

    2014-10-01

    Duplex capillary columns, the standard for electrochromatography using optical detection, consist of a packed and an open section. Normally, optical detection is performed in an on-column manner, i.e. at a point right after the packed section. It was deemed that band broadening may take place when an analyte band travels from the packed bed, through the frit and down to the open section. In this study, without using any sintering steps for fritting or window creation, robust packed capillary columns were prepared using transparent capillaries based on single particle fritting technology. The detection point could be easily shifted by simply sliding the transparent column against the ultraviolet (UV) beam. In this way, the band broadening effect was directly evaluated as a function of the detection point, which was positioned before or after the end frit. The consistent van Deemter curves recorded indicate that there was no efficiency difference between the positions investigated. The result proved that the significant band broadening effect previously observed via on-column detection should be caused by the sintered frit used, while the single particle frit made through a purely physical process did not lead to efficiency degradation. The conservative separation performance recorded at different positions around the column's end also suggests the applicability of on-line tandem detection strategy, e.g. UV followed by mass spectrometry (MS), on the same capillary column, which should be a promising approach to mining multiplex detection information from a single microseparation process. PMID:25171946

  8. Hydrodynamic chromatography of macromolecules on 2 ?m non-porous spherical silica gel packings

    Microsoft Academic Search

    J. C. Kraak; R. Oostervink; H. Poppe; U. Esser; K. K. Unger

    1989-01-01

    Non-porous spherical 2?m silica gel particles have been tested as packing for hydrodynamic chromatography of macromolecules (HDC). Columns packed with these particles in 250×4.6mm i.d. columns can be operated very efficiently (e.g. a reduced plate height of about 2) when the detection cell is miniaturized. The packing is suitable for the separation of polystyrenes of Mw of 104–107 by hydrodynamic

  9. Determination of plate efficiencies for conventional distillation columns

    E-print Network

    Harris, Thomas Raymond

    1962-01-01

    IV. Values of Ei, Qi, P , and Vapor Rates Obtained in the Solution of Example 2 Values of Ei, Vapor Rates, Temperatures and 61 bi/di Specifications for Example 3 . . . . . . . 62 Values of Ei and Vapor Rates Obtained in the Solution of Example... 3 . ~ ~ ~ ~ ~ ~ ~ 64 VI. Values of Ei, bi/di, p , and Vapor Rates Obtained in the Solution of Example 4 . . . ~ . . 65 VI I. VIII. Values of P and V for Examples 5-10 Equilibrium Data 66 67 IX. EnthalpF Data 68 IBTRODUCTIOH The term most...

  10. Packing Patterns into Words

    Microsoft Academic Search

    Alexander Burstein; Peter Hästö; Toufik Mansour

    2002-01-01

    Abstract In this article we generalize packing density problems from permutations to patterns with repeated letters and generalized patterns We are able to find the packing density for some classes of patterns and several other short patterns

  11. On Discrete Hyperbox Packing 

    E-print Network

    Li, Xiafeng

    2010-01-14

    Bin packing is a very important and popular research area in the computer science field. Past work showed many good and real-world packing algorithms. How- ever, due to the complexity of the problem in multiple-dimensional bin packing, also called...

  12. Column Chromatography

    NSDL National Science Digital Library

    Julie Yu

    2007-01-01

    In this activity, learners separate the components of Gatorade using a home-made affinity column. In doing so, learners model the basic principle of affinity chromatography, a technique used to purify chemicals as well as bio-pharmaceuticals and petroleum products. This resource contains information about affinity chromatography and polarity.

  13. Random sphere packing lattices

    NASA Astrophysics Data System (ADS)

    Kallus, Yoav

    2015-03-01

    Bravais lattices have always been an important special case of the high-dimensional sphere packing problem, but from the statistical mechanics and random packing perspectives, they have not been studied much until recently. I will discuss the statistical mechanical phenomena exhibited by a system of one sphere under periodic boundary conditions, where the only degrees of freedom are the unit cell parameters. Equilibrium behavior includes a ``crystallization'' transition, but most of the interest comes from studying non-equilibrium behavior: glass transition, random packing, and hysteresis. The random-packed lattices exhibit surprising properties, including a density remarkably higher than amorphous random packing and a quasicontact divergence.

  14. Distillation Apparatuses Using Household Items

    Microsoft Academic Search

    Danielle R. D. Campanizzi; Brenda Mason; Christine K. F. Hermann

    1999-01-01

    A simple apparatus to demonstrate distillation principles can be very difficult to build without the specialty glassware found in chemistry laboratories. We have built inexpensive but effective distillation apparatuses from equipment that can be easily purchased at local department, grocery, or hardware stores. In one apparatus, colored water is heated to boiling and the condensed vapors drip into another container.

  15. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...material, using any quantity of water desired to facilitate fermentation or distillation. No sugar may be added in the production...material. Distillates containing aldehydes may be used in the fermentation of wine to be used as distilling material. Lees,...

  16. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...material, using any quantity of water desired to facilitate fermentation or distillation. No sugar may be added in the production...material. Distillates containing aldehydes may be used in the fermentation of wine to be used as distilling material. Lees,...

  17. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...material, using any quantity of water desired to facilitate fermentation or distillation. No sugar may be added in the production...material. Distillates containing aldehydes may be used in the fermentation of wine to be used as distilling material. Lees,...

  18. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...material, using any quantity of water desired to facilitate fermentation or distillation. No sugar may be added in the production...material. Distillates containing aldehydes may be used in the fermentation of wine to be used as distilling material. Lees,...

  19. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...material, using any quantity of water desired to facilitate fermentation or distillation. No sugar may be added in the production...material. Distillates containing aldehydes may be used in the fermentation of wine to be used as distilling material. Lees,...

  20. Vapor compression distillation module

    NASA Technical Reports Server (NTRS)

    Nuccio, P. P.

    1975-01-01

    A Vapor Compression Distillation (VCD) module was developed and evaluated as part of a Space Station Prototype (SSP) environmental control and life support system. The VCD module includes the waste tankage, pumps, post-treatment cells, automatic controls and fault detection instrumentation. Development problems were encountered with two components: the liquid pumps, and the waste tank and quantity gauge. Peristaltic pumps were selected instead of gear pumps, and a sub-program of materials and design optimization was undertaken leading to a projected life greater than 10,000 hours of continuous operation. A bladder tank was designed and built to contain the waste liquids and deliver it to the processor. A detrimental pressure pattern imposed upon the bladder by a force-operated quantity gauge was corrected by rearranging the force application, and design goals were achieved. System testing has demonstrated that all performance goals have been fulfilled.

  1. Adding rectifying\\/stripping section type heat integration to a pressure-swing distillation (PSD) process

    Microsoft Academic Search

    Kejin Huang; Lan Shan; Qunxiong Zhu; Jixin Qian

    2008-01-01

    This paper studies the economical effect of considering rectifying\\/stripping section type heat integration in a pressure-swing distillation (PSD) process separating a binary homogeneous pressure-sensitive azeotrope. The schemes for arranging heat integration between the rectifying section and the stripping section of the high- and low-pressure distillation columns, respectively, are derived and an effective procedure is devised for the conceptual process design

  2. Leaf Pack Network

    NSDL National Science Digital Library

    The Leaf Pack Network (LPN) is a network of teachers and students investigating their local stream ecosystems by participating in the leaf pack experiment, which involves creating an artificial leaf pack (dry leaves in a mesh bag), immersing it in a stream for 3-4 weeks, and examining it for signs of aquatic insects as indicators of stream health. Participating classrooms share their data through the internet. This activity highlights the connection between streamside forests and the ecology of rivers and streams.

  3. Optimal Control of Distillation Systems

    E-print Network

    Chatterjee, N.; Suchdeo, S. R.

    1984-01-01

    The optimum performance of a distillation system can be evaluated by examining the product purities, the product recoveries, and the system's capability to respond to small or large, expected or unexpected, plant disturbances. An optimal control...

  4. Revamp for more middle distillate

    SciTech Connect

    Weeks, D.J.; Pierce, V.E.

    1985-03-01

    In view of the continued decline in demand for residual fuel oil, the much publicised tightness of refining margins and hence funds for new investment, it is appropriate at this time to review some relatively inexpensive, but well-proven, revamp options that are available to the refiner for increasing yields of mid-distillate products at the expense of fuel oil components. With the partial or complete closure of so much refining capacity, much surplus equipment is available for implementing revamp projects. There is also scope for revamping hitherto moth-balled units and operating them in a manner different from that envisaged during their original design. Some long established conversion processes such as visbreaking and thermal cracking can enjoy a renaissance if demand for distillates remains strong. Mild hydrocracking and distillate dewaxing which are more recent developments in refinery processing can also figure prominently in plans for incremental production of middle distillates.

  5. Quantum entanglement distillation with metamaterials.

    PubMed

    Al Farooqui, Md Abdullah; Breeland, Justin; Aslam, Muhammad I; Sadatgol, Mehdi; Özdemir, ?ahin K; Tame, Mark; Yang, Lan; Güney, Durdu Ö

    2015-07-13

    We propose a scheme for the distillation of partially entangled two-photon Bell and three-photon W states using metamaterials. The distillation of partially entangled Bell states is achieved by using two metamaterials with polarization dependence, one of which is rotated by ?/2 around the direction of propagation of the photons. On the other hand, the distillation of three-photon W states is achieved by using one polarization dependent metamaterial and two polarization independent metamaterials. Upon transmission of the photons of the partially entangled states through the metamaterials the entanglement of the states increases and they become distilled. This work opens up new directions in quantum optical state engineering by showing how metamaterials can be used to carry out a quantum information processing task. PMID:26191854

  6. Distillation control: For productivity and energy conservation

    Microsoft Academic Search

    Skinskey

    1984-01-01

    The introduction of new types of distillation control equipment has necessitated the publication of this second edition. Thermodynamic principles, flow ratios, composition control, and azeotropic distillation are among the topics covered. It includes bibliographies, computer programs suitable for distillation calculations, and a subject index. Contents Distillation fundamentals. Control system structure. Complex processes. Optimization. Appendices. Index.

  7. Analysis of organic/inorganic analytes in environmental samples by packed capillary chromatography

    SciTech Connect

    Burford, M.D.; Robson, M.M.; Mitchell, S.C. [Univ. of Leeds (United Kingdom)] [and others

    1995-12-31

    Recent progress in the development of techniques for packing of high efficiency capillary columns has enabled the concept of unified chromatography to be realised. Packed capillary columns offer the advantages of both packed column (high loading capacity, wide range of stationary phases) and capillary column (speed of analysis, high resolution) techniques to produce a versatile and efficient analytical procedure. For the detailed investigation of fossil fuel and environmental samples the rapid growth of packed capillary chromatography offers the unique opportunity to analyse both organic and inorganic components as the column can be operated in both gas chromatography (GC) and supercritical fluid chromatography (SFC) modes. In this study, the use of packing capillary columns, prepared in-house is investigated for both high pressure GC and SFC using helium and CO{sub 2} as the mobile phase respectively. Several spiked and real world samples have been used to demonstrate the potential of packed capillary columns in the analysis of organic and inorganic analytes in fuel and environmental samples.

  8. Characterisation of electroosmotic flow in capillary electrochromatography columns.

    PubMed

    Dearie, H S; Spikmans, V; Smit, N W; Moffatt, F; Wren, S A; Evans, K P

    2001-09-21

    Currently available capillary electrochromatography (CEC) instrumentation using UV-Vis detection dictates the use of duplex columns. Due to discontinuities (electric field strength and conductivity) that arise at the boundary between the packed and open sections in these columns, the determination of the electroosmotic flow (EOF) is complicated. Thiourea has been found to be an accurate EOF marker under the conditions employed in this study. By injecting this compound onto a fully packed column and comparing the obtained mobilities with those calculated from measured zeta potential values a value for tortuosity has been obtained. The use of laser Doppler velocimetry (LDV) for the measurement of zeta potential has been found to be the most direct and rapid method of characterising silica support materials in terms of electroosmotic mobility. The open section in duplex CEC columns has been shown to influence the actual column flow-rate. The EOF measured using duplex columns of varying packed and open section lengths have been compared with those obtained for a fully packed column. PMID:11594393

  9. Radiotracer Imaging of Sediment Columns

    NASA Astrophysics Data System (ADS)

    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, E? = 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 (<1 day). This allows multiple measurements to be made on the same column and thus the sediment biology to be monitored non-invasively over time (i.e. after an augmentation has been introduced) and minimizes long-lived radioactive waste. Different parameters can be measured, depending on the tracer type and delivery. A constant infusion of a conservative tracer, such as the positron emitter Br-76 (T1/2= 16.2 hr), measures the exclusion fraction (as a function of position in the column), while a bolus maps the flow velocity as a function of position. A tracer that interacts chemically with the contents of the column (e.g., [99m-Tc(VII)O4]- reduced to 99m-TcO2 by Fe(II) ) yields a map of the chemical environment (e.g., the distribution of Fe(II)). Image of Tc-99m distribution in a column containing Rifle sediment at four times.

  10. Graphitic packing removal tool

    DOEpatents

    Meyers, Kurt Edward (Avella, PA); Kolsun, George J. (Pittsburgh, PA)

    1997-01-01

    Graphitic packing removal tools for removal of the seal rings in one piece. he packing removal tool has a cylindrical base ring the same size as the packing ring with a surface finish, perforations, knurling or threads for adhesion to the seal ring. Elongated leg shanks are mounted axially along the circumferential center. A slit or slits permit insertion around shafts. A removal tool follower stabilizes the upper portion of the legs to allow a spanner wrench to be used for insertion and removal.

  11. Graphitic packing removal tool

    SciTech Connect

    Meyers, K.E.; Kolsun, G.J.

    1996-12-31

    Graphitic packing removal tools are described for removal of the seal rings in one piece from valves and pumps. The packing removal tool has a cylindrical base ring the same size as the packing ring with a surface finish, perforations, knurling or threads for adhesion to the seal ring. Elongated leg shanks are mounted axially along the circumferential center. A slit or slits permit insertion around shafts. A removal tool follower stabilizes the upper portion of the legs to allow a spanner wrench to be used for insertion and removal.

  12. Distillation Apparatuses Using Household Items

    NASA Astrophysics Data System (ADS)

    Campanizzi, Danielle R. D.; Mason, Brenda; Hermann, Christine K. F.

    1999-08-01

    A simple apparatus to demonstrate distillation principles can be very difficult to build without the specialty glassware found in chemistry laboratories. We have built inexpensive but effective distillation apparatuses from equipment that can be easily purchased at local department, grocery, or hardware stores. In one apparatus, colored water is heated to boiling and the condensed vapors drip into another container. In another apparatus, acetone is heated to boiling with hot water and the acetone vapors condense onto a Styrofoam cup. The Styrofoam cup is softened by the acetone and collapses. Rubbing alcohol can be used instead of acetone, but the cup is not softened and the boiling point is much higher. Both apparatuses can be used in a classroom. Both are simple, cost-effective ways of demonstrating distillation, evaporation, and condensation. They would be ideal to use in elementary and middle school classrooms when explaining these concepts.

  13. Solar power water distillation unit

    NASA Astrophysics Data System (ADS)

    Hameed, Kamran; Muzammil Khan, Muhammad; Shahrukh Ateeq, Ijlal; Omair, Syed Muhammad; Ahmer, Muhammad; Wajid, Abdul

    2013-06-01

    Clean drinking water is the basic necessity for every human being, but about 1.1 billion people in the world lacked proper drinking water. There are many different types of water purification processes such as filtration, reverse osmosis, ultraviolet radiation, carbon absorption, but the most reliable processes are distillation and boiling. Water purification, such as distillation, is especially important in regions where water resources or tap water is not suitable for ingesting without boiling or chemical treatment. In design project It treats the water by combining different methods such as Filtration, Distillation and a technique called concentrated solar power (CSP). Distillation is literally the method seen in nature, whereby: the sun heats the water on the earth's surface, the water is turned into a vapor (evaporation) and rises, leaving contaminants behind, to form clouds. As the upper atmosphere drops in temperature the vapors cool and convert back to water to form water. In this project distillation is achieved by using a parabolic mirror which boils water at high temperature. Filtration is done by sand filter and carbon filter. First sand filter catches the sand particles and the carbon filter which has granules of active carbon is used to remove odor dissolved gases from water. This is the Pre-treatment of water. The filtered water is then collected in a water container at a focus of parabolic mirror where distillation process is done. Another important feature of designed project is the solar tracking of a parabolic mirror which increases the efficiency of a parabolic mirror [1],[2].

  14. The purpose of this pack This pack presents the Forestry

    E-print Network

    The purpose of this pack This pack presents the Forestry Commission's key messages on climate change. It draws together the information available from the Forestry Commission, Forest Research in tackling climate change. Who is this pack aimed at? The pack is primarily aimed at Forestry Commission

  15. Nasal packing and stenting

    PubMed Central

    Weber, Rainer K.

    2011-01-01

    Nasal packs are indispensable in ENT practice. This study reviews current indications, effectiveness and risks of nasal packs and stents. In endoscopic surgery, nasal packs should always have smooth surfaces to minimize mucosal damage, improve wound healing and increase patient comfort. Functional endoscopic endonasal sinus surgery allows the use of modern nasal packs, since pressure is no longer required. So called hemostatic/resorbable materials are a first step in this direction. However, they may lead to adhesions and foreign body reactions in mucosal membranes. Simple occlusion is an effective method for creating a moist milieu for improved wound healing and avoiding dryness. Stenting of the frontal sinus is recommended if surgery fails to produce a wide, physiologically shaped drainage path that is sufficiently covered by intact tissue. PMID:22073095

  16. Evaluation of Packed Columns in Supercritical Extraction Processes

    E-print Network

    Rathkamp, P. J.; Fair, J. R.; Humphrey, J. L.

    rings. The SFE systems studied were carbon dioxide/ethanol/water and carbon digxide/isopropanol/water at 102 atmos pheres and 35 C and 102 atmospheres and 40 0 C, res pectively. In order to compare supercritical with conventional solvent extraction... to extract twelve model compounds (such as ethanol, ethyl butyrate, and limonene) from an aqueous feed. These compounds were used to simulate a model mixture of oranee essence. Schultz found that the feed rate had the largest effect on the percent...

  17. Sequential Vector Packing

    Microsoft Academic Search

    Mark Cieliebak; Alexander Hall; Riko Jacob; Marc Nunkesser

    2007-01-01

    We introduce a novel variant of the well known d-dimensional bin (or vector) packing problem. Given a sequence of non-negative d-dimensional vectors, the goal is to pack these into as few bins as possible. In the classical problem the bin size vector is given and the sequence can be partitioned arbi- trarily. We study a variation where the vectors have

  18. Distillation of hydrogen isotopes for polarized HD target

    E-print Network

    Ohta, T; Didelez, J -P; Fujiwara, M; Fukuda, K; Kohri, H; Kunimatsu, T; Morisaki, C; Ono, S; Rouill', G; Tanaka, M; Ueda, K; Uraki, M; Utsuro, M; Wang, S Y; Yosoi, M

    2011-01-01

    We have developed a cryogenic distillation system to purify Hydrogen-Deuteride (HD) gas for a polarized HD target in LEPS experiments at SPring-8. A small amount of ortho-H$_2$ ($\\sim$0.01%) in the HD gas plays an important role in efficiently polarizing the HD target. Since there are 1$\\sim$5% impurities of H$_2$ and D$_2$ in commercially available HD gases, it is inevitable that the HD gas is purified up to $\\sim$99.99%. The distillation system has a cryogenic pot (17$\\sim$21 K) containing many small stainless steel cells called Heli-pack. Commercial HD gas with an amount of 5.2 mol is fed into the pot. We carried out three distillation runs by changing temperatures (17.5 K and 20.5 K) and gas extraction speeds (1.3 ml/min and 5.2 ml/min). The extracted gas was analyzed by using a gas analyzer system combining a quadrupole mass spectrometer with a gas chromatograph. The HD gas of 1 mol with a purity better than 99.99% has been successfully obtained. The effective NTS (Number of Theoretical Stages), which is...

  19. Distillation: Present Status and Future Directions

    E-print Network

    Fair, J. R.; Humphrey, J. L.

    1984-01-01

    Distillation will undoubtedly continue to be the most-used method for separating liquid mixtures, at any scale of operation. For this reason, and also because of its recognized energy intensiveness, distillation commands continued scrutiny...

  20. Design and optimization of a dividing wall column for debottlenecking of the acetic acid purification process

    Microsoft Academic Search

    Nguyen Van Duc Long; Seunghyun Lee; Moonyong Lee

    2010-01-01

    The dividing wall column (DWC) has gained increasing application in a variety of chemical processes because of its potentiality in energy and capital cost savings in multicomponent separations. The main objective in this work is investigation of its use for removing the bottleneck phenomenon within the column when increasing the throughput of an existing distillation process, particularly, the acetic acid

  1. OPPORTUNITIES FOR UTILIZING DISTILLERS GRAINS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fuel ethanol industry is currently experiencing unprecedented growth. In conjunction with this expansion, the quantity of distillers grains produced over time has grown in parallel. This industry has continually evolved, and technological innovations and process changes have been implemented tha...

  2. 27 CFR 19.322 - Distillates containing extraneous substances.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Distillates containing aldehydes may be removed, without payment of tax, to an adjacent bonded wine cellar for use therein for fermentation of wine to be used as distilling material at the distilled spirits plant from which the distillates were removed....

  3. 21 CFR 184.1848 - Starter distillate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Starter distillate (butter starter distillate) is a steam distillate of the culture of any or all of the following species of bacteria grown on a medium consisting of skim milk usually fortified with about 0.1 percent citric acid: Streptococcus...

  4. 21 CFR 184.1848 - Starter distillate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Starter distillate (butter starter distillate) is a steam distillate of the culture of any or all of the following species of bacteria grown on a medium consisting of skim milk usually fortified with about 0.1 percent citric acid: Streptococcus...

  5. 21 CFR 184.1848 - Starter distillate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Starter distillate (butter starter distillate) is a steam distillate of the culture of any or all of the following species of bacteria grown on a medium consisting of skim milk usually fortified with about 0.1 percent citric acid: Streptococcus...

  6. Pessimal shapes for packing

    NASA Astrophysics Data System (ADS)

    Kallus, Yoav

    2014-03-01

    The question of which convex shapes leave the most empty space in their densest packing is the subject of Reinhardt's conjecture in two dimensions and Ulam's conjecture in three dimensions. Such conjectures about pessimal packing shapes have proven notoriously difficult to make progress on. I show that the regular heptagon is a local pessimum among all convex shapes, and that the 3D ball is a local pessimum among origin-symmetric shapes. Any shape sufficiently close in the space of shapes to these local pessima can be packed at a greater efficiency than they. In two dimensions and in dimensions above three, the ball is not a local pessimum, so the situation in 3D is unusual and intriguing. I will discuss what conditions conspire to make the 3D ball a local pessimum and whether we can prove that it is also a global pessimum.

  7. Mechanisms of recirculating liquid flow on distillation sieve plates

    SciTech Connect

    Biddulph, M.W. (Univ. of Nottingham (United Kingdom). Dept. of Chemical Engineering); Burton, A.C. (BOC Group, Murray Hill, NJ (United States))

    1994-11-01

    This paper describes an experimental investigation into the phenomenon of flow recirculation on distillation sieve trays. A novel dye injection technique has been applied to a 1.81 m air-water simulation column and has yielded new information concerning the nature of the boundary layer of gas-liquid biphase as it detaches from the column wall. The study has shown that recirculation is strongly influenced by inlet conditions. A critical factor is the underflow clearance between the inlet downcomer apron and the tray floor. As this clearance is increased, the size of the recirculating zones passes through a minimum, indicating the existence of two different mechanisms responsible for the nonuniform flow patterns. A significant implication of this work is that tray designers may minimize the impact of recirculating on mass transfer efficiency by appropriate choice of underflow clearance.

  8. Distillate Market Model documentation report

    SciTech Connect

    Not Available

    1993-12-01

    The purpose of this report is to define the objectives of the Distillate Market Model (DMM), describe its basic approach, and to provide details on model functions. This report is intended as a reference document for model analysts, users, and the general public. Documentation of the model is in accordance with EIA`s legal obligation to provide adequate documentation in support of its models. The DMM performs a short-term (6- to 9-month) forecast of demand and retail price for distillate fuel oil in the national US market; it also calculates the end-of-month stock level during the term of the forecast. The model is used to analyze certain market behavior assumptions or shocks and to determine the effect on retail market price, demand, and stock level.

  9. Knapsack packing networks.

    PubMed

    Hellstrom, B J; Kanal, L N

    1992-01-01

    A knapsack packing neural network of 4n units with both low-order and conjunctive asymmetric synapses is derived from a non-Hamiltonian energy function. Parallel simulations of randomly generated problems of size n in {5, 10, 20} are used to compare network solutions with those of simple greedy fast parallel enumerative algorithms. PMID:18276431

  10. Nutrition Action Pack.

    ERIC Educational Resources Information Center

    Sockut, Joanne; Stumpe, Stephanie

    One of five McDonald's Action Packs, these instructional materials integrate elementary school-level nutrition education into other disciplines--biology, sociology, physiology, mathematics, and art. Contents include four units consisting of twelve activities. Unit 1, Why You Need Food, is a self-examination of what is needed for growth, health,…

  11. DIY Fraction Pack.

    ERIC Educational Resources Information Center

    Graham, Alan; Graham, Louise

    2003-01-01

    Describes a very successful attempt to teach fractions to year 5 pupils based on pupils making their own fraction pack. Children decided for themselves how to make the fractional slices used in the activity using colored cardboard sheets and templates of a paper circle consisting of 24 equal slices. (Author/NB)

  12. TCAP HYDROGEN ISOTOPE SEPARATION USING PALLADIUM AND INVERSE COLUMNS

    SciTech Connect

    Heung, L.; Sessions, H.; Xiao, S.

    2010-08-31

    The Thermal Cycling Absorption Process (TCAP) was further studied with a new configuration. Previous configuration used a palladium packed column and a plug flow reverser (PFR). This new configuration uses an inverse column to replace the PFR. The goal was to further improve performance. Both configurations were experimentally tested. The results showed that the new configuration increased the throughput by a factor of more than 2.

  13. Optimization of blended battery packs

    E-print Network

    Erb, Dylan C. (Dylan Charles)

    2013-01-01

    This thesis reviews the traditional battery pack design process for hybrid and electric vehicles, and presents a dynamic programming (DP) based algorithm that eases the process of cell selection and pack design, especially ...

  14. HEXAHYDRO-1,3,5-TRINITRO-1,3,5-TRIAZINE (RDX) DEGRADATION IN BIOLOGICALLY-ACTIVE IRON COLUMNS

    E-print Network

    Alvarez, Pedro J.

    sequencing revealed a predominance of Acetobacterium sp. in the iron layer of all columns after 95 daysHEXAHYDRO-1,3,5-TRINITRO-1,3,5-TRIAZINE (RDX) DEGRADATION IN BIOLOGICALLY-ACTIVE IRON COLUMNS BYUNG iron barriers to treat groundwater contamination by RDX. Three columns were packed with iron filings

  15. Numerical Simulation of the Anaerobic Transformation of Tetrachloroethene to cis-Dichloroethene in a Continuous Flow Aquifer Column

    Microsoft Academic Search

    N. Mustafa; M. Azizian; M. Dolan; L. Semprini

    2007-01-01

    The anaerobic reductive dechlorination of tetrachloroethene (PCE) to cis-dichloroethene (c-DCE) in a laboratory column study was numerically simulated and compared with experimental observations. The column study was conducted with continuous flow and injection of PCE in synthetic groundwater. The column was packed with aquifer solids from the Hanford DOE site and bioaugmented with the Evanite (EV) dechlorinating enrichment culture. After

  16. Prepacking perforations improves gravel packs

    SciTech Connect

    Hall, B.E.; Pace, J.R. (Western Co., The Woodlands, TX (US))

    1990-05-21

    Productivity can be increased by prepacking perforations with gravel before a major gravel pack is pumped. The main gravel-pack treatment follows immediately after the prepack. This procedure can increase perforation permeability due to a more complete gravel fill of the perforation. The gravel pack prevents perforations from collapsing or filling with formation sand.

  17. Packed Bed Combustion: An Overview

    E-print Network

    Hallett, William L.H.

    Packed Bed Combustion: An Overview William Hallett Dept. of Mechanical Engineering Université d'Ottawa - University of Ottawa #12;Packed Bed Combustion - University of Ottawa - CICS 2005 Introduction air fuel feedproducts xbed grate Packed Bed Combustion: fairly large particles of solid fuel on a grate, air supplied

  18. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons...3 2 “Fairly tight” means that apples are of the proper size for...

  19. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons...3 2 “Fairly tight” means that apples are of the proper size for...

  20. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons...3 2 “Fairly tight” means that apples are of the proper size for...

  1. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons...3 2 “Fairly tight” means that apples are of the proper size for...

  2. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons...3 2 “Fairly tight” means that apples are of the proper size for...

  3. Selfish Bin Packing

    Microsoft Academic Search

    Leah Epstein; Elena Kleiman

    2008-01-01

    Following recent interest in the study of computer science problems in a game theoretic setting, we consider the well known\\u000a bin packing problem where the items are controlled by selfish agents. Each agent is charged with a cost according to the fraction\\u000a of the used bin space its item requires. That is, the cost of the bin is split among

  4. Selfish Bin Packing

    Microsoft Academic Search

    Leah Epstein; Elena Kleiman

    2011-01-01

    Following recent interest in the study of computer science problems in a game theoretic setting, we consider the well known\\u000a bin packing problem where the items are controlled by selfish agents. Each agent is charged with a cost according to the fraction\\u000a of the used bin space its item requires. That is, the cost of the bin is split among

  5. Enumerating rigid sphere packings

    E-print Network

    Miranda C. Holmes-Cerfon

    2015-05-08

    Packing problems, which ask how to arrange a collection of objects in space to meet certain criteria, are important in a great many physical and biological systems, where geometrical arrangements at small scales control behaviour at larger ones. In many systems there is no single, optimal packing that dominates, but rather one must understand the entire set of possible packings. As a step in this direction we enumerate rigid clusters of identical hard spheres for $n\\leq 14$, and clusters with the maximum number of contacts for $n\\leq 19$. A rigid cluster is one that cannot be continuously deformed while maintaining all contacts. This is a nonlinear notion that arises naturally because such clusters are the metastable states when the spheres interact with a short-range potential, as is the case in many nano- or micro-scale systems. We expect these lists are nearly complete, except for a small number of highly singular clusters (linearly floppy but nonlinearly rigid.) The data contains some major geometrical surprises, such as the prevalence of hypostatic clusters: those with less than the $3n-6$ contacts generically necessary for rigidity. We discuss these and several other unusual clusters, whose geometries may shed insight into physical mechanisms, pose mathematical and computational problems, or bring inspiration for designing new materials.

  6. Determination of fenpyroximate in apples by supercritical fluid extraction and packed capillary liquid chromatography with UV detection

    Microsoft Academic Search

    B. L Halvorsen; C Thomsen; T Greibrokk; E Lundanes

    2000-01-01

    A method using off-line supercritical fluid extraction (SFE) and micro liquid chromatography (?LC) with UV detection at 260 nm, was developed for selective determination of fenpyroximate in apple samples. The packed capillary liquid chromatography method utilises 20 ?l injection volumes with on-column focusing. A 350×0.32 mm capillary column packed with Kromasil 100-C18 of 5 ?m particle size was used with

  7. Five points on columns

    E-print Network

    Rockland, Kathleen

    Column,” like “gene,” has both conceptual and linguistic shortcomings. The simple question “what is a column” is not easy to answer and the word itself is not easy to replace. In the present article, I have selected five ...

  8. Neuro-estimator based GMC control of a batch reactive distillation.

    PubMed

    Prakash, K J Jithin; Patle, Dipesh S; Jana, Amiya K

    2011-07-01

    In this paper, an artificial neural network (ANN)-based nonlinear control algorithm is proposed for a simulated batch reactive distillation (RD) column. In the homogeneously catalyzed reactive process, an esterification reaction takes place for the production of ethyl acetate. The fundamental model has been derived incorporating the reaction term in the model structure of the nonreactive distillation process. The process operation is simulated at the startup phase under total reflux conditions. The open-loop process dynamics is also addressed running the batch process at the production phase under partial reflux conditions. In this study, a neuro-estimator based generic model controller (GMC), which consists of an ANN-based state predictor and the GMC law, has been synthesized. Finally, this proposed control law has been tested on the representative batch reactive distillation comparing with a gain-scheduled proportional integral (GSPI) controller and with its ideal performance (ideal GMC). PMID:21334616

  9. Computational Fluid Dynamics Simulation of Structured Packing Scott A. Owens, Michael R. Perkins, and R. Bruce Eldridge*

    E-print Network

    Eldridge, R. Bruce

    -quality volume mesh. The mesh was then utilized to produce a series of CFD simulations. Flow rates were chosen so packing. Grid generation was performed automatically using adaptive mesh generation software with user to approximate a packed column. The resulting three-dimensional image file was imported into the Star-CCM+ CFD

  10. 3D printed metal columns for capillary liquid chromatography.

    PubMed

    Sandron, S; Heery, B; Gupta, V; Collins, D A; Nesterenko, E P; Nesterenko, P N; Talebi, M; Beirne, S; Thompson, F; Wallace, G G; Brabazon, D; Regan, F; Paull, B

    2014-12-21

    Coiled planar capillary chromatography columns (0.9 mm I.D. × 60 cm L) were 3D printed in stainless steel (316L), and titanium (Ti-6Al-4V) alloys (external dimensions of ~5 × 30 × 58 mm), and either slurry packed with various sized reversed-phase octadecylsilica particles, or filled with an in situ prepared methacrylate based monolith. Coiled printed columns were coupled directly with 30 × 30 mm Peltier thermoelectric direct contact heater/cooler modules. Preliminary results show the potential of using such 3D printed columns in future portable chromatographic devices. PMID:25285334

  11. DESIGN SCALE-UP SUITABILITY FOR AIR-STRIPPING COLUMNS (JOURNAL VERSION)

    EPA Science Inventory

    An investigation was conducted to determine the suitability of a design scale-up from pilot-scale to full-scale air-stripping columns used in the removal of volatile organic compounds from contaminated water supplies. Forty-eight experimental runs were made in packed columns of f...

  12. TRANSPORT OF MACROMOLECULES AND HUMATE COLLOIDS THROUGH A SAND AND A CLAY AMENDED SAND LABORATORY COLUMN

    EPA Science Inventory

    Laboratory experiments were conducted to determine if macromolecules or humate colloids would transport through sand columns and if they would exhibit any variations in their relative velocity based upon their molecular volumes and the pore size distribution of the column packing...

  13. Shell and small particles; evaluation of new column technology.

    PubMed

    Fekete, Szabolcs; Fekete, Jeno; Ganzler, Katalin

    2009-01-15

    The performance of 5 cm long columns packed with shell particles was compared to totally porous sub-2 microm particles in gradient and isocratic elution separations of hormones (dienogest, finasteride, gestodene, levonorgestrel, estradiol, ethinylestradiol, noretistherone acetate, bicalutamide and tibolone). Peak capacities around 140-150 could be achieved in 25 min with the 5 cm long columns. The Ascentis Express column (packed with 2.7 microm shell particles) showed similar efficiency to sub-2 microm particles under gradient conditions. Applying isocratic separation, the column of 2.7 microm shell particles had a reduced plate height minimum of approximately h=1.6. It was much smaller than obtained with totally porous particles (h approximately = 2.8). The impedance time also proved more favorable with 2.7 microm shell particles than with totally porous particles. The influence of extra-column volume on column efficiency was investigated. The extra-column dispersion of the chromatographic system may cause a shift of the HETP curves. PMID:19038515

  14. The impact of extra-column band broadening on the chromatographic efficiency of 5 cm long narrow-bore very efficient columns.

    PubMed

    Fekete, Szabolcs; Fekete, Jeno

    2011-08-01

    Small columns packed with core-shell and sub-2 ?m totally porous particles and monolith columns are very popular to conduct fast and efficient chromatographic separations. In order to carry out fast separations, short (2-5 cm) and narrow-bore (2-2.1 mm) columns are used to decrease the analyte retention volume. Beside the column efficiency, another significant issue is the extra-column band-spreading. The extra-column dispersion of a given LC system can dramatically decrease the performance of a small very efficient column. The aim of this study was to compare the extra-column peak variance contribution of several commercially available LC systems. The efficiency loss of three different type 5 cm long narrow bore, very efficient columns (monolith, sub-2 ?m fully porous and sub-2 ?m core-shell packing) as a function of extra-column peak variance, and as a function of flow rate and also kinetic plots (analysis time versus apparent column efficiency) are presented. PMID:21726868

  15. Improving the Performance of a Two-Shell Column with Advanced Control

    E-print Network

    Morrison, T. A.; Laflamme, D.

    ~e~s of the steam flow and the top composltlon would stay below setpoint unless reflux was run extremely low. The soft target composition is the C4 content of the distillate. The value for the composition target is either set by the operator or by an energy... Balancing Shells Approximates Single Distillation Column The original column controls included a stripping temperature controller setting the steam flow. This was never reliable and thestea~flow was set manually. It would be desIrable to use a composition...

  16. Locally accessible information and distillation of entanglement

    SciTech Connect

    Ghosh, Sibasish [Department of Computer Science, University of York, Heslington, York, YO10 (United Kingdom); Joag, Pramod [Department of Physics, University of Pune, Ganeshkhind, Pune 411 007 (India); Kar, Guruprasad; Kunkri, Samir [Physics and Applied Mathematics Unit, Indian Statistical Institute, 203, B.T. Road, Kolkata 700 108 (India); Roy, Anirban [Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600 113 (India)

    2005-01-01

    A different type of complementarity relation is found between locally accessible information and final average entanglement for a given ensemble. It is also shown that in some well-known distillation protocols, this complementary relation is optimally satisfied. We discuss the interesting trade-off between locally accessible information and distillable entanglement for some states.

  17. Locally Accessible Information and Distillation of Entanglement

    E-print Network

    Ghosh, S; Kar, G; Kunkri, S; Roy, A; Ghosh, Sibasish; Joag, Pramod; Kar, Guruprasad; Kunkri, Samir; Roy, Anirban

    2004-01-01

    A new type of complementary relation is found between locally accessible information and final average entanglement for given ensemble. It is also shown that in some well known distillation protocol, this complementary relation is optimally satisfied. We discuss the interesting trade-off between locally accessible information and distillable entanglement for some states.

  18. Experience with distillation unit computer control

    SciTech Connect

    Rinne, R.; Sunell, H.; Latour, P.R.; Paynter, K.K.

    1982-03-01

    In this paper, control improvements, operating experience and operator acceptance are presented for a computer control and optimization project on a 140 Mbpd crude distillation unit. The process description is followed by a presentation of control objectives and functions (atmospheric residue, distillate yields, energy conservation, product quality); operator tasks; results; operators acceptance; system availability and operating experience. 5 refs.

  19. Water Purification by Membrane Distillation Process

    Microsoft Academic Search

    Marek Gryta

    2006-01-01

    The demineralization of water by membrane distillation (MD) has been investigated. In the first stage of investigations the tap water or boiled tap water was employed as a feed, and the water recovery coefficient exceeding 75% was achieved. The obtained concentrate was supplied to the second stage of MD installation. The quality of distillate was stable and practically independent of

  20. Key Blog Distillation: Ranking Aggregates Craig Macdonald

    E-print Network

    Jose, Joemon M.

    Key Blog Distillation: Ranking Aggregates Craig Macdonald University of Glasgow Glasgow, Scotland interests to their own. How- ever, a main difference of this blog distillation task from normal adhoc or Web document retrieval is that each blog can be seen as an aggregate of its constituent posts. On the other

  1. Potential bleaching techniques for corn distillers grains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ethanol industry is booming, and extensive research is now being pursued to develop alternative uses for distillers dried grains (DDG) and distillers dried grains with solubles (DDGS), coproducts of the ethanol production process. Currently, DDG and DDGS are used exclusively as livestock feed. P...

  2. IMPACTS OF PACKING SECTION ON MASS TRANSFER TO DROP SWARMS

    Microsoft Academic Search

    D. Chen; W. Fei; H. R. C. Pratt; G. W. Stevens

    2001-01-01

    Terminal velocity and mass transfer coefficient data for drop swarms were measured in a 0.1 m diameter glass column filled with SMR (Super Mini Ring) packing, using a computerized video imaging system; 30% TBP-Kerosene\\/acetic acid\\/water and 50% TBP-Kerosene\\/acetic acid\\/water were used as the working systems. A number of techniques for the prediction of the observed mass transfer data were considered,

  3. Liquid chromatography on soft packing material, under axial compression

    Microsoft Academic Search

    A. V. Danilov; I. V. Vagenina; L. G. Mustaeva; S. A. Moshnikov; E. Yu Gorbunova; V. V. Cherskii; M. B. Baru

    1997-01-01

    The behaviour of Sephadex G-25 gel packing for size-exclusion chromatography under dynamic axial compression in a 100×2.5 cm column of original design has been studied. The influence of dynamic axial compression on the bed structure and its chromatographic performance was determined with polypeptide samples of various molecular mass. In the studied range of compression pressure values (1.74–5.22 bar), a considerable

  4. 7 CFR 160.9 - Destructively distilled wood turpentine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 false Destructively distilled wood turpentine. 160.9 Section 160.9...General § 160.9 Destructively distilled wood turpentine. The designation “destructively distilled wood turpentine” shall refer to the kind...

  5. 7 CFR 160.9 - Destructively distilled wood turpentine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 false Destructively distilled wood turpentine. 160.9 Section 160.9...General § 160.9 Destructively distilled wood turpentine. The designation “destructively distilled wood turpentine” shall refer to the kind...

  6. 40 CFR 721.9635 - Terpene residue distillates.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Terpene residue distillates. 721.9635 Section...Specific Chemical Substances § 721.9635 Terpene residue distillates. (a) Chemical...chemical substance identified generically as terpene residue distillates (PMN...

  7. 40 CFR 721.9635 - Terpene residue distillates.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Terpene residue distillates. 721.9635 Section...Specific Chemical Substances § 721.9635 Terpene residue distillates. (a) Chemical...chemical substance identified generically as terpene residue distillates (PMN...

  8. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 2012-01-01 2012-01-01 false Steam distilled wood turpentine. 160.8 Section...STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer...

  9. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 2014-01-01 2014-01-01 false Steam distilled wood turpentine. 160.8 Section...STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer...

  10. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 2010-01-01 2010-01-01 false Steam distilled wood turpentine. 160.8 Section...STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer...

  11. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 2013-01-01 2013-01-01 false Steam distilled wood turpentine. 160.8 Section...STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer...

  12. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 2011-01-01 2011-01-01 false Steam distilled wood turpentine. 160.8 Section...STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer...

  13. Optimal steady-state design of reactive distillation processes using simulated annealing

    Microsoft Academic Search

    Jian-Kai Cheng; Hao-Yeh Lee; Hsiao-Ping Huang; Cheng-Ching Yu

    2009-01-01

    In this paper, we investigate on a derivative-free optimization approach, simulated annealing (SA), for the optimization of the reactive distillation (RD) column design. Because RD systems exhibit non-monotonic behavior for key design variables, flowsheet optimization using simulator is difficult when derivative-based approach is employed. The SA-based optimization procedure gives an equally good or better design than the optimal flowsheet obtained

  14. Application of high vacuum fractional distillation to complex mixtures of methyl esters of polyunsaturated fatty acids

    Microsoft Academic Search

    O. S. Privett; J. D. Nadenicek; F. J. Pusch; E. C. Nickell

    1969-01-01

    A technique for the high vacuum fractional distillation, with a spinning band column, of methyl esters of polyunsaturated\\u000a fatty acids employing a carrier of long chain acetates is described. The carrier is used to facilitate the fractionation of\\u000a minor components and minimize artifact formation in mixtures of methyl esters containing up to six double bonds. The technique\\u000a is demonstrated on

  15. Aromatic characterization of pot distilled kiwi spirits.

    PubMed

    López-Vázquez, Cristina; García-Llobodanin, Laura; Pérez-Correa, José Ricardo; López, Francisco; Blanco, Pilar; Orriols, Ignacio

    2012-03-01

    This study contributes fundamental knowledge that will help to develop a distillate of kiwi wine, made from kiwis of the Hayward variety grown in the southwest of Galicia (Spain). Two yeast strains, L1 (Saccharomyces cerevisiae ALB-6 from the EVEGA yeast collection) and L2 (S. cerevisiae Uvaferm BDX from Lallemand) were assessed to obtain a highly aromatic distillate. The kiwi spirits obtained were compared with other fruit spirits, in terms of higher alcohols, minor alcohols, monoterpenols, and other minor compounds, which are relevant in determining the quality and taste of the kiwi spirits. It was found that the kiwi juice fermented with yeast L1 produced a more aromatic distillate. In addition, kiwi distillates produced with both yeasts had the same ratio of trans-3-hexen-1-ol and cis-3-hexen-1-ol, which is lower than that found in other fruit distillates. PMID:22321168

  16. Endurance Test for SCK-CEN Catalytic Mixed Packing, Proposed for Water Detritiation System at JET

    SciTech Connect

    Ionita, Gh. [National Institute for Cryogenics and Isotopic Separation (Romania); Bornea, A. [National Institute for Cryogenics and Isotopic Separation (Romania); Braet, J. [SCK-CEN (Belgium); Popescu, I. [National Institute for Cryogenics and Isotopic Separation (Romania); Stefanescu, I. [National Institute for Cryogenics and Isotopic Separationn (Romania); Bidica, N. [National Institute for Cryogenics and Isotopic Separation (Romania); Varlam, C [National Institute for Cryogenics and Isotopic Separation (Romania); Postolache, Cr. [National Insitute of Physics and Nuclear Engineering (Romania); Mateic, L. [National Insitute of Physics and Nuclear Engineering (Romania)

    2005-07-15

    JET machine's operation lead to continuously generation of tritiated water and therefore, it is necessary to consider the development of a Water Detritiation System (WDS) for JET and also for ITER. The key point of WDS is the efficiency and stability of liquid phase catalytic exchange (LPCE) column, that has to achieve a high decontamination of tritiated streams.Two catalytic mixed packing based on hydrophobic Pt-catalyst, and having closed separation performances have been proposed for LPCE column. A complete data base concerning the influence of {beta}-radiation of tritium and the influence of impurities from feed streams on the catalytic mixed packing' s performances and parameters is absolutely necessary.The results of 3 months endurance test for one of these packing (SCK-CEN packing), are presented in this paper. No significant modifications of performances and physico-structural parameters have been observed.

  17. Shell middle distillate hydrogenation process

    SciTech Connect

    Lucien, J.P. [Companie Rhenane de Raffinage Reichstett, Reichstett Vendenheim (France); Berg, J.P. van den; Hooijdonk, H.M.J.H. van; Thielemans, G.L.B. [Shell Internationale Petroleum Mij., The Hague (Netherlands); Germaine, G. [Shell Recherche SA, Grand-Couronne (France); Gjers, M. [Shell Raffinaderi AB, Gothenburg (Sweden)

    1994-12-31

    The strive towards cleaner environment has lead to low sulfur specifications for middle distillate fuels. In addition compositional specifications are presently debated. Thus, to meet future emissions standards regarding, specifically, particulates emissions, the motor industry calls for improved automotive gasoil quality. Although automotive gasoil quality affects emissions from diesel engines it is considered less influential than engine design and maintenance. Sulfur, density and cetane number are the fuel properties having the greatest influence on diesel engine emissions although also aromatics and endpoint specifications have been defined in environmentally adopted government initiatives. This paper reviews the options which are available to tackle these new requirements. The high severity single stage concept (using conventional mixed sulfides catalysts) will be discussed in its potential to meet more severe product requirements as well as in terms of its limitations, especially at the point of aromatics saturation and cetaine upgrading. Furthermore, it is shown that the option of severe hydrotreating followed by hydrogenation with conventional noble metal catalysts is preferred if deep aromatics saturation is aimed at. However, this conventional two stage concept has limitations with respect to heaviness and sulfur and nitrogen content of feedstocks. The new Shell Middle Distillate Hydrogenation (SMDH) technology, applying a (semi) two stage approach based on the Shell developed hydrogenation catalyst is presented. The SMDH process will be discussed in its potential to break the limitations of the conventional options. The new catalyst is crucial in this process and allows a highly integrated mode of operation. A number of applications of this novel process will be discussed.

  18. Computational fluid dynamic simulation of fluid flow in a rotating packed bed

    Microsoft Academic Search

    Wenjing Yang; Yundong Wang; Jianfeng Chen; Weiyang Fei

    2010-01-01

    Rotating packed bed (RPB) has been widely used in absorption, desorption, distillation, oxidation, crystallization, precipitation, polymerization, and production of nanoparticles. RPB utilizes centrifugal acceleration to intensify the mixing and mass-transfer processes. Under high-gravity, molecule diffusions are much faster than under normal gravity. With the centrifugal force generated by rotation, RPBs have considerable high mass-transfer and micromixing performance. However, because of

  19. The book review column

    Microsoft Academic Search

    William I. Gasarch

    2004-01-01

    Welcome to the Book Reviews Column. We hope to bring you at least two reviews of books every month. In this column four books are reviewed. 1. Stable Marriage and its Relation to Other Combinatorial Problems: An Intro- duction to Algorithm Analysis by Donald Knuth. Reviewed by Tim McNichol. This book uses the stable marriage problem as motivation to look

  20. 7 CFR 58.331 - Starter distillate.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...PRODUCTS 1 General Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.331 Starter distillate. The refined flavor components when used to flavor butter and related...

  1. Absorptive Recycle of Distillation Waste Heat 

    E-print Network

    Erickson, D. C.; Lutz, E. J., Jr.

    1982-01-01

    When the heat source available to a distillation process is at a significantly higher temperature than the reboiler temperature, there is unused availability (ability to perform work) in the heat supplied to the reboiler. Similarly, if the reflux...

  2. Energy Recovery in Industrial Distillation Processes

    E-print Network

    Paul, D. B.

    1983-01-01

    Distillation processes are energy intensive separation processes which present attractive opportunities for energy conservation. Through the use of multistage vapor recompression, heat which is normally unavailable can be delivered at suitably high...

  3. Absorptive Recycle of Distillation Waste Heat

    E-print Network

    Erickson, D. C.; Lutz, E. J., Jr.

    1982-01-01

    When the heat source available to a distillation process is at a significantly higher temperature than the reboiler temperature, there is unused availability (ability to perform work) in the heat supplied to the reboiler. Similarly, if the reflux...

  4. Energy Conservation Options in Distillation Processes

    E-print Network

    Harris, G. E.; Hearn, W. R.; Blythe, G. M.; Stuart, J. M.

    1980-01-01

    This paper summarizes the results of a survey of energy conservation options applicable to distillation processes. Over twenty such options were identified, and eight of these were selected for detailed presentation. These options were chosen...

  5. Minimizing corrosion in coal liquid distillation

    DOEpatents

    Baumert, Kenneth L. (Emmaus, PA); Sagues, Alberto A. (Lexington, KY); Davis, Burtron H. (Georgetown, KY)

    1985-01-01

    In an atmospheric distillation tower of a coal liquefaction process, tower materials corrosion is reduced or eliminated by introduction of boiling point differentiated streams to boiling point differentiated tower regions.

  6. What kind of pack and basic packing guide page: What kind of pack

    E-print Network

    Blanchette, Robert A.

    tolerable. ! The Backpack The backpack is with good reason the most common choice for young travelers frame style packs. An external frame pack is more comfortable for long and intensive backpacking. It allows the weight to rest more comfortably on your hips and gives ventilation to keep you cooler

  7. Modeling of column flotation

    SciTech Connect

    Luttrell, G.H.; Adel, G.T.; Yoon, R.H.

    1987-01-01

    Many investigators believe that column flotation cells offer significant advantages over standard mechanical machines for the flotation of fine particles. However, because of their unique design and operation, conventional techniques for flotation cell scale-up and design cannot be applied to columns. In an attempt to help alleviate this problem, a population balance model based on first principles has been developed for fine particle flotation in a column. Two different terms have been considered in the model, i.e., transport and rate. Transport terms, incorporating fluid flow and buoyancy, are used to describe the movement of air bubbles, unattached particles and bubble-particle aggregates along the length of the column. Rate terms, which describe the bubble-particle attachment process, have been derived from first principle considerations. Because the model is based on first principles, it can be useful for the design, control, optimization and scale-up of column flotation cells. 9 refs., 12 figs.

  8. JCE Feature Columns

    NASA Astrophysics Data System (ADS)

    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 in the Chemistry Curriculum, and WWW Site Review. These columns differ from the print feature columns in that they use the Internet as the publication medium. Doing so allows these features to include continually updated information, digital components, and links to other online resources. The Conceptual Questions and Challenge Problems feature of JCE Internet serves as a good example for the kinds of resources that you can expect to find in an online feature column. Like other columns it contains a mission statement that defines the role of the column. It includes a digital library of continually updated examples of conceptual questions and challenge problems. (As I write this we have just added several new questions to the library.) It also includes a list of links to related online resources, information for authors about how to write questions and problems, and information for teachers about how to use conceptual questions and challenge problems. Teaching with Technology home page at JCE Online. One-Stop Feature Shop The updated Feature area of JCE Online offers information about all JCE feature columns in one place. It gives you a quick and convenient way to access a group of articles in a particular subject area. It provides authors and readers with a good definition of the column and its mission. It complements the print feature columns with online resources. It provides up-to-date bibliographies for selected areas of interest. And last, but not least, it provides that email address you can use to send that message of appreciation to the feature editor for his or her contribution to JCE and the chemical education community.

  9. Multipartite secret key distillation and bound entanglement

    SciTech Connect

    Augusiak, Remigiusz; Horodecki, Pawel [Faculty of Applied Physics and Mathematics, Gdansk University of Technology, Narutowicza 11/12, 80-952 Gdansk (Poland) and ICFO-Institute Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona) (Spain); Faculty of Applied Physics and Mathematics, Gdansk University of Technology, Narutowicza 11/12, 80-952 Gdansk (Poland)

    2009-10-15

    Recently it has been shown that quantum cryptography beyond pure entanglement distillation is possible and a paradigm for the associated protocols has been established. Here we systematically generalize the whole paradigm to the multipartite scenario. We provide constructions of new classes of multipartite bound entangled states, i.e., those with underlying twisted Greenberger-Horne-Zeilinger (GHZ) structure and nonzero distillable cryptographic key. We quantitatively estimate the key from below with the help of the privacy squeezing technique.

  10. Valve stem and packing assembly

    DOEpatents

    Wordin, J.J.

    1991-09-03

    A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by means of a spring, gland flange, and gland on the stem packing so the stem packing seals to the valve stem and bonnet. This configuration serves to create and maintain a reliable seal between the stem packing and the valve stem. The bonnet includes a second complementary tractrix surface for contacting the second sliding tractrix surface, the combination serving as a journal bearing for the entire valve stem and packing assembly. The journal bearing so configured is known as a Schiele's pivot. The Schiele's pivot also serves to maintain proper alignment of the valve stem with respect to the bonnet. Vertical wear between the surfaces of the Schiele's pivot is uniform at all points of contact between the second sliding tractrix surface and the second complementary tractrix surface of a bonnet. The valve stem is connected to a valve plug by means of a slip joint. The valve is opened and closed by rotating the valve stem. The slip joint compensates for wear on the Schiele's pivot and on the valve plug. A ledge is provided on the valve bonnet for the retaining nut to bear against. The ledge prevents over tightening of the retaining nut and the resulting excessive friction between stem and stem packing. 2 figures.

  11. Valve stem and packing assembly

    DOEpatents

    Wordin, John J. (Bingham County, ID)

    1991-01-01

    A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by means of a spring, gland flange, and gland on the stem packing so the stem packing seals to the valve stem and bonnet. This configuration serves to create and maintain a reliable seal between the stem packing and the valve stem. The bonnet includes a second complementary tractrix surface for contacting the second sliding tractrix surface, the combination serving as a journal bearing for the entire valve stem and packing assembly. The journal bearing so configured is known as a Schiele's pivot. The Schiele's pivot also serves to maintain proper alignment of the valve stem with respect to the bonnet. Vertical wear between the surfaces of the Schiele's pivot is uniform at all points of contact between the second sliding tractrix surface and the second complementary tractrix surface of a bonnet. The valve stem is connected to a valve plug by means of a slip joint. The valve is opened and closed by rotating the valve stem. The slip joint compensates for wear on the Schiele's pivot and on the valve plug. A ledge is provided on the valve bonnet for the retaining nut to bear against. The ledge prevents overtightening of the retaining nut and the resulting excessive friction between stem and stem packing.

  12. Dense periodic packings of tori

    NASA Astrophysics Data System (ADS)

    Gabbrielli, Ruggero; Jiao, Yang; Torquato, Salvatore

    2014-02-01

    Dense packings of nonoverlapping bodies in three-dimensional Euclidean space R3 are useful models of the structure of a variety of many-particle systems that arise in the physical and biological sciences. Here we investigate the packing behavior of congruent ring tori in R3, which are multiply connected nonconvex bodies of genus 1, as well as horn and spindle tori. Specifically, we analytically construct a family of dense periodic packings of unlinked tori guided by the organizing principles originally devised for simply connected solid bodies [22 Torquato and Jiao, Phys. Rev. E 86, 011102 (2012), 10.1103/PhysRevE.86.011102]. We find that the horn tori as well as certain spindle and ring tori can achieve a packing density not only higher than that of spheres (i.e., ? /?18 =0.7404...) but also higher than the densest known ellipsoid packings (i.e., 0.7707...). In addition, we study dense packings of clusters of pair-linked ring tori (i.e., Hopf links), which can possess much higher densities than corresponding packings consisting of unlinked tori.

  13. Tritum recovery system from waste water of fusion reactor using CECE and cryogenic-wall thermal diffusion column

    SciTech Connect

    Arita, T.; Yamanishi, T.; Iwai, Y.; Okuno, K. [Japan Atomic Energy Research Inst., Ibaraki (Japan); Kobayashi, N.; Yamamoto, I. [Nagoya Univ. (Japan)

    1996-12-31

    A system for recovery of tritium in water has been proposed. The system is composed of CECE (Combined Electrolysis Chemical Exchange) and CTD (Cryogenic-wall Thermal Diffusion) columns. A design study was carried out for the two cases: the waste water processing in fusion facilities; and the tritium recovery from heavy water in a fission reactor in Japan. The size and power consumption of the system can greatly be reduced by using the CECE column than the system of WD (Water Distillation) columns. The operation and maintenance of the CTD column are quite easier than the CD (Cryogenic Distillation) column. The proposed system would be applicable for some cases such as the waste water processing in tritium facilities, where the processing flow rate is relatively small. 11 refs., 4 figs., 6 tabs.

  14. Packing grains by thermally cycling

    E-print Network

    K. Chen; J. Cole; C. Conger; J. Draskovic; M. Lohr; K. Klein; T. Scheidemantel; P. Schiffer

    2006-08-04

    One of the oldest and most intriguing problems in the handling of materials is how a collection of solid grains packs together. While granular packing is normally determined by how grains are poured or shaken, we find that a systematic and controllable increase in packing is induced by simply raising and lowering the temperature, e.g., without the input of mechanical energy. The results demonstrate that thermal processing provides a largely unexplored mechanism of grain dynamics, as well as an important practical consideration in the handling and storage of granular materials.

  15. The current revolution in column technology: how it began, where is it going?

    PubMed

    Gritti, Fabrice; Guiochon, Georges

    2012-03-01

    This work revisits the exceptionally rapid evolution of the technology of chromatographic columns and the important progress in speed of analysis and resolution power that was achieved over the last ten years. Whereas columns packed with 10 and 5 ?m fully porous particles dominated the field for nearly thirty years (1975-2000), it took barely six years to see the commercialization of monolithic silica rods (2000), their raise to fame and decay to oblivion, the development of finer fully porous particles with size down to 1.7 ?m (2006), and of sub-3 ?m superficially porous particles (2006). Analysis times and plate heights delivered by columns packed with these recent packing materials have then been improved by more than one order of magnitude in this short period of time. This progress has rendered practically obsolete the age-old design of LC instruments. For low molecular weight compounds, analysts can now achieve peak capacities of 40 peaks in about 15s with a hold-up time of the order of 1.5s , in gradient elution, by operating columns packed with sub-3 ?m shell particles at elevated temperatures, provided that they use optimized high pressure liquid chromatographs. This is the ultimate limit allowed by modern instruments, which have an extra-column band broadening contribution of 7 ?L² at 4.0 mL/min and data acquisition rate of 160 Hz. The best 2.1 mm × 50 mm narrow-bore columns packed with 1.7 ?m silica core-shell particles provide peaks that have a variance of 2.1 ?L² for k=1. Finally, this work discusses possible ways to accelerate separations and, in the same time perform these separations at the same level of efficiency as they have today. It seems possible to pack columns with smaller particles, probably down to 1 ?m and operate them with current vHPLC equipments for separations of biochemicals. Analyses of low molecular weight compounds will require new micro-HPLC systems able to operate 1mm I.D. columns at pressures up to 5 kbar, which would eliminate the heat friction problems, and providing extra-column band broadening contributions smaller than 0.1 ?L². Alternatively, a new generation of vHPLC systems with minimal extra-column contributions of less than 0.5 ?L² could run 2.1mm I.D. columns if these latter were to be packed with high heat conductivity materials such as core-shell particles made with an alumina or gold core. PMID:21872874

  16. Nuclear reactor control column

    DOEpatents

    Bachovchin, Dennis M. (Plum Borough, PA)

    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 cross-sectional 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.

  17. Composite Column Design

    NSDL National Science Digital Library

    Johnson, Craig

    This module, created by Craig Johnson of Central Washington University, "incorporates engineering design (using smart spreadsheets) into a laboratory activity focusing on columns made of composite materials." In this lab, students will simulate the use of composite columns and use spreadsheets to optimize design for engineering performance. The module features an abstract, objective, curriculum overview, procedures, mathematical calculations and references. The objectives of the module are to design appropriate composite column structures, fabricate composite using appropriate methods and critically evaluate composite's performance referencing predications. This is a great resource to either enhance or create new curriculum for instructors.

  18. [Scale-up of conical column with 10 degree opening angle as preparative liquid chromatographic column].

    PubMed

    Lu, Liejuan; Chen, Jie; Guan, Yafeng

    2009-05-01

    A preparative scale liquid chromatographic column with the conical shape of 10 degrees opening angle was constructed and evaluated. The column was designed with the inlet/outlet diameters of 54/27 mm, the column length of 150 mm and the column volume of 200 mL, and packed with the spherical C18 bonded silica with the particle size of 40-75 microm and the aperture of 11 nm. The mobile phase in the conical column showed a plug like flow profile and plug like chromatographic band shape. For naphthalene, the reduced plate height was about 2.11; the maximum sample load was 2.1 mg or 1.7 mL (10% reduction of plate number), which is 20%, 16% and 19% higher than that of cylindrical one of the same length and volume. As the injection mass increased from 2. 4 mg up to 12 mg, the resolution of ethyl paraben/butyl (R, ) reduced from 2. 14 down to 1.71, and the butyl paraben/naphthalene (Rs3) from 2.91 down to 2.52; the injection volume increased from 3 mL up to 19 mL, Rs2, reduced from 2.23 down to 1.28, and Rs3 from 2.95 down to 2.30, while the peaks were still in symmetric shape without tailing. This characteristic of the column shall benefit for the separation of trace components from matrix. This demonstrated the conical shaped preparative columns would have a broad practical applicability for obtaining pure compounds. PMID:19803133

  19. Soil column leaching of pesticides.

    PubMed

    Katagi, Toshiyuki

    2013-01-01

    In this review, I address the practical and theoretical aspects of pesticide soil mobility.I also address the methods used to measure mobility, and the factors that influence it, and I summarize the data that have been published on the column leaching of pesticides.Pesticides that enter the unsaturated soil profile are transported downwards by the water flux, and are adsorbed, desorbed, and/or degraded as they pass through the soil. The rate of passage of a pesticide through the soil depends on the properties of the pesticide, the properties of the soil and the prevailing environmental conditions.Because large amounts of many different pesticides are used around the world, they and their degradates may sometimes contaminate groundwater at unacceptable levels.It is for this reason that assessing the transport behavior and soil mobility of pesticides before they are sold into commerce is important and is one indispensable element that regulators use to assess probable pesticide safety. Both elementary soil column leaching and sophisticated outdoor lysimeter studies are performed to measure the leaching potential for pesticides; the latter approach more reliably reflects probable field behavior, but the former is useful to initially profile a pesticide for soil mobility potential.Soil is physically heterogeneous. The structure of soil varies both vertically and laterally, and this variability affects the complex flow of water through the soil profile, making it difficult to predict with accuracy. In addition, macropores exist in soils and further add to the complexity of how water flow occurs. The degree to which soil is tilled, the density of vegetation on the surface, and the type and amounts of organic soil amendments that are added to soil further affect the movement rate of water through soil, the character of soil adsorption sites and the microbial populations that exist in the soil. Parameters that most influence the rate of pesticide mobility in soil are persistence (DT50) of the pesticide, and its sorption/desorption(Koc) characteristics. These parameters may vary for the same pesticide from geographic site-to-site and with soil depth. The interactions that normally occur between pesticides and dissolved organic matter (DOM) or WDC are yet other factors that may complicate pesticide leaching behavior.The soil mobility of pesticides is normally tested both in the laboratory and in the field. Lab studies are initially performed to give researchers a preliminary appraisal of the relative mobility of a pesticide. Later, field lysimeter studies can be performed to provide more natural leaching conditions that emulate the actual field use pattern. Lysimeter studies give the most reliable information on the leaching behavior of a pesticide under field conditions, but these studies are time-consuming and expensive and cannot be performed everywhere. It is for this reason that the laboratory soil column leaching approach is commonly utilized to profile the mobility of a pesticide,and appraise how it behaves in different soils, and relative to other pesticides.Because the soil structure is chemically and physically heterogenous, different pesticide tests may produce variable DT50 and Koc values; therefore, initial pesticide mobility testing is undertaken in homogeneously packed columns that contain two or more soils and are eluted at constant flow rates. Such studies are done in duplicate and utilize a conservative tracer element. By fitting an appropriate mathematical model to the breakthrough curve of the conservative tracer selected,researchers determine key mobility parameters, such as pore water velocity, the column-specific dispersion coefficient, and the contribution of non equilibrium transport processes. Such parameters form the basis for estimating the probable transport and degradation rates that will be characteristic of the tested pesticide. Researchers also examine how a pesticide interacts with soil DOM and WDC, and what contribution from facilitated transport to mobility is made as a result of the effects of

  20. Effect of feeding distiller’s grains on reduced sulfur emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Odorous reduced sulfur compounds are produced during manure decomposition and emitted from confined animal feeding operations. Feeding high-sulfur distiller’s byproducts may increase the emission of these compounds. The objectives of a series of feedlot pen studies was to (i) determine if emission...

  1. Polymethacrylate monolithic and hybrid particle-monolithic columns for reversed-phase and hydrophilic interaction capillary liquid chromatography.

    PubMed

    Jandera, Pavel; Urban, Jirí; Skeríková, Veronika; Langmaier, Pavel; Kubícková, Romana; Planeta, Josef

    2010-01-01

    We prepared hybrid particle-monolithic polymethacrylate columns for micro-HPLC by in situ polymerization in fused silica capillaries pre-packed with 3-5microm C(18) and aminopropyl silica bonded particles, using polymerization mixtures based on laurylmethacrylate-ethylene dimethacrylate (co)polymers for the reversed-phase (RP) mode and [2-(methacryloyloxy)ethyl]-dimethyl-(3-sulfopropyl) zwitterionic (co)polymers for the hydrophilic interaction (HILIC) mode. The hybrid particle-monolithic columns showed reduced porosity and hold-up volumes, approximately 2-2.5 times lower in comparison to the pure monolithic columns prepared in the whole volume of empty capillaries. The elution volumes of sample compounds are also generally lower in comparison to packed or pure monolithic columns. The efficiency and permeability of the hybrid columns are intermediate in between the properties of the reference pure monolithic and particle-packed columns. The chemistries of the embedded solid particles and of the interparticle monolithic moiety in the hybrid capillary columns contribute to the retention to various degrees, affecting the selectivity of separation. Some hybrid columns provided improved separations of proteins in comparison to the reference particle-packed columns in the reversed-phase mode. Zwitterionic hybrid particle-monolithic columns show dual mode retention HILIC/RP behaviour depending on the composition of the mobile phase and allow separations of polar compounds such as phenolic acids in the HILIC mode at lower concentrations of acetonitrile and, often in shorter analysis time in comparison to particle-packed and full-volume monolithic columns. PMID:19800628

  2. Estimation of the column radial heterogeneity from an analysis of the characteristics of tailing peaks in linear chromatography

    Microsoft Academic Search

    Kanji Miyabe; Georges Guiochon

    1999-01-01

    An estimation procedure of the radial heterogeneity of the distributions of the mobile phase flow velocity and of the local column efficiency was derived from a comparison of experimental data and of the characteristics of these tailing peaks calculated numerically. The analysis of these characteristics indicated that the radial heterogeneity of the packing density of a column is a cause

  3. Limits and Consequences of Nonlocality Distillation

    NASA Astrophysics Data System (ADS)

    Rashid, Jibran

    Only in the last few decades have we realized how to view quantum nonlocal correlations as possible information theoretic resources rather than as apparent paradoxes. Unfortunately, the past perspective in terms of paradoxes still persists in our considerations of nonlocal boxes (NLBs) that offer stronger than quantum nonlocal correlations. We argue that a more pragmatic approach is to consider the physical framework under which such correlations may be realized. Our consideration immediately yields fruit by allowing us to identify limitations of the NLB model and develop the generalized notion of a quantum nonlocal box ( qNLB). We analyze the NLB and qNLB models within the framework of nonlocality distillation protocols. The ability to concentrate the correlations of many identical noisy copies of a nonlocal correlation source is known as nonlocality distillation. The idea is still in its early stages of development and and we pursue it in this thesis. We develop multiple new nonlocality distillation protocols and prove the optimality of non-adaptive distillation protocols for both NLBs and qNLBs. We show that qNLBs offer stronger non-adaptive distillation protocols than NLBs. At the same time, the understanding we develop is that there is no single optimal adaptive protocol for NLB distillation. The choice of which protocol to use depends on the noise parameters for the NLB. Through our investigation of nonlocality distillation protocols we conclude that the qNLB model is a stronger resource for nonlocality than NLBs. The main premise that develops from this conclusion is that the NLB model is not the strongest resource to investigate the fundamental principles that limit quantum nonlocality. As such, our work provides strong motivation to reconsider the status quo of the principles that limit nonlocal correlations under the framework of qNLBs rather than NLBs. As a first step towards the re-examination of such principles, we provide numerical evidence that the distillability of nonlocal correlations depends on properties that are local. We claim that the differing strength of distillation protocols for NLBs and qNLBs can be interpreted as a separation between classical and quantum predictions at the macroscopic level. This implies that there exist quantum correlations that can be observed in principle, at the macroscopic level or that the principle of macroscopic locality identifies exactly the set of quantum correlations.

  4. Axial dispersion in gases flowing through a packed bed at elevated pressures

    Microsoft Academic Search

    A. H. Benneker; A. E. Kronberg; J. W. Post; K. R. Westerterp

    1996-01-01

    Axial dispersion in upward gas flow is investigated by pulse and displacement experiments in a vertical, packed column with different concentrations of the tracer and at pressures up to 1.5 MPa. The responses to the introduced pulse and step changes are measured at two locations and the extent of axial dispersion, respresented by the Bodenstein number, is determined by curve

  5. Acoustics Australia Vol. 41, No. 1, April 2013 107 QUANTIFYING THE ACOUSTIC PACKING

    E-print Network

    techniques. The time taken for the sonar to process the water-column backscatter is one of the limitingAcoustics Australia Vol. 41, No. 1, April 2013 107 QUANTIFYING THE ACOUSTIC PACKING DENSITY OF FISH twenty or so years MBS systems have been increasingly employed to map mid-water schools of fish in deeper

  6. Towards Atomic Column-by-Column Spectroscopy

    SciTech Connect

    Pennycook, S.J.; Rafferty, B.

    1998-09-06

    The optical arrangement of the scanning transmission electron microscope (STEM) is ideally suited for performing analysis of individual atomic columns in materials. Using the incoherent Z-contrast image as a reference, and arranging incoherent conditions also for the spectroscopy, a precise correspondence is ensured between features in the inelastic image and elastic signals. In this way the exact probe position needed to maximise the inelastic signal from a selected column can be located and monitored during the analysis using the much higher intensity elastic signal. Although object functions for EELS are typically less than 1 {Angstrom} full width at half maximum, this is still an order of magnitude larger than the corresponding object functions for elastic (or diffuse) scattering used to form the Z-contrast image. Therefore the analysis is performed with an effective probe that is significantly broader than that used for the reference Z-contrast image. For a 2.2 {Angstrom} probe the effective probe is of the order of 2.5 {Angstrom}, while for a 1.3 {Angstrom} probe the effective probe is 1.6 {Angstrom}. Such increases in effective probe size can significantly reduce or even eliminate contrast between atomic columns that are visible in the image. However, this is only true if we consider circular collector apertures. Calculations based upon the theory of Maslen and Rossouw (Maslen and Rossouw 1984; Rossouw and Maslen 1984) show that employing an annular aperture can reduce the FWHM of the inelastic object function down to values close 0.1 {Angstrom}. With practical aperture sizes it should be possible to achieve this increased spatial resolution without loosing too much signal.

  7. Heat transfer studies of packed bed coal liquefaction reactors

    SciTech Connect

    Holcombe, N. T.; Knickle, H. N.; Yavorsky, P. M.

    1980-06-01

    The effective thermal conductivity (K/sub e/) and wall heat transfer coefficient (H/sub w/) were determined in a packed bed reactor model over a range of gas mass velocities from 0 to 15,000 kg/m/sup 2/ hr, liquid mass velocities from 5000 to 65,000 kg/m/sup 2/ hr, and pressures that simulate coal liquefaction pressures from 1000 to 4000 psig. A correlation for K/sub e/ and H/sub w/ was developed for the range of study. Several mathematical models for one and two dimensions, and for one and two parameters, were derived to describe two-phase flow in packed beds. Two flow regimes are described. The entrance effects for the low liquid flow regime seem to be limited to a length of about ten diameters, while the entrance effects for the high liquid flow seem to extend through the entire length of the column.

  8. Sleeping distance in wild wolf packs

    USGS Publications Warehouse

    Knick, S.T.; Mech, L.D.

    1980-01-01

    Sleeping distances were observed among members of 13 wild wolf (Canis lupus) packs and 11 pairs in northeastern Minnesota to determine if the distances correlated with pack size and composition. The study utilized aerial radio-tracking and observation during winter. Pack size and number of adults per pack were inversely related to pack average sleeping distance and variability. No correlation between sleeping distance and microclimate was observed. Possible relationships between social bonding and our results are discussed.

  9. High pressure humidification columns: Design equations, algorithm, and computer code

    SciTech Connect

    Enick, R.M. [Pittsburgh Univ., PA (United States). Dept. of Chemical and Petroleum Engineering; Klara, S.M. [USDOE Pittsburgh Energy Technology Center, PA (United States); Marano, J.J. [Burns and Roe Services Corp., Pittsburgh, PA (United States)

    1994-07-01

    This report describes the detailed development of a computer model to simulate the humidification of an air stream in contact with a water stream in a countercurrent, packed tower, humidification column. The computer model has been developed as a user model for the Advanced System for Process Engineering (ASPEN) simulator. This was done to utilize the powerful ASPEN flash algorithms as well as to provide ease of use when using ASPEN to model systems containing humidification columns. The model can easily be modified for stand-alone use by incorporating any standard algorithm for performing flash calculations. The model was primarily developed to analyze Humid Air Turbine (HAT) power cycles; however, it can be used for any application that involves a humidifier or saturator. The solution is based on a multiple stage model of a packed column which incorporates mass and energy, balances, mass transfer and heat transfer rate expressions, the Lewis relation and a thermodynamic equilibrium model for the air-water system. The inlet air properties, inlet water properties and a measure of the mass transfer and heat transfer which occur in the column are the only required input parameters to the model. Several example problems are provided to illustrate the algorithm`s ability to generate the temperature of the water, flow rate of the water, temperature of the air, flow rate of the air and humidity of the air as a function of height in the column. The algorithm can be used to model any high-pressure air humidification column operating at pressures up to 50 atm. This discussion includes descriptions of various humidification processes, detailed derivations of the relevant expressions, and methods of incorporating these equations into a computer model for a humidification column.

  10. Vacuum distillation/vapor filtration water recovery

    NASA Technical Reports Server (NTRS)

    Honegger, R. J.; Neveril, R. B.; Remus, G. A.

    1974-01-01

    The development and evaluation of a vacuum distillation/vapor filtration (VD/VF) water recovery system are considered. As a functional model, the system converts urine and condensates waste water from six men to potable water on a steady-state basis. The system is designed for 180-day operating durations and for function on the ground, on zero-g aircraft, and in orbit. Preparatory tasks are summarized for conducting low gravity tests of a vacuum distillation/vapor filtration system for recovering water from urine.

  11. Advanced Distillation: Programs Proposed to DOE 

    E-print Network

    Woinsky, S. G.

    2001-01-01

    revolutionary changes rather than sm(lll evolutionary changes in the way distillation is practiced in the US chemical industry, and olller U.S industries that lise distillation. sllch as petroleum refining. All approach called Heal Integrated Distributed.../Yr Petroleum Fuel Fractions 0.493 0,082 Crude Oil 0.423 Water -lnoHmnics 0,057 Liauefied Petroleum Gas 0,217 Air 0,017 Oletins 0.118 Water - HCs 0,007 Miscellaneous Hydrocarbons (HCs) 0.101 Other 0,302 Water - Oxygenated HCs 0.100 Total Reboiler Ener!!v 1...

  12. Reducing CO2 emissions and energy consumption of heat-integrated distillation systems.

    PubMed

    Gadalla, Mamdouh A; Olujic, Zarko; Jansens, Peter J; Jobson, Megan; Smith, Robin

    2005-09-01

    Distillation systems are energy and power intensive processes and contribute significantly to the greenhouse gases emissions (e.g. carbon dioxide). Reducing CO2 emissions is an absolute necessity and expensive challenge to the chemical process industries in orderto meetthe environmental targets as agreed in the Kyoto Protocol. A simple model for the calculation of CO2 emissions from heat-integrated distillation systems is introduced, considering typical process industry utility devices such as boilers, furnaces, and turbines. Furnaces and turbines consume large quantities of fuels to provide electricity and process heats. As a result, they produce considerable amounts of CO2 gas to the atmosphere. Boilers are necessary to supply steam for heating purposes; besides, they are also significant emissions contributors. The model is used in an optimization-based approach to optimize the process conditions of an existing crude oil atmospheric tower in order to reduce its CO2 emissions and energy demands. It is also applied to generate design options to reduce the emissions from a novel internally heat-integrated distillation column (HIDiC). A gas turbine can be integrated with these distillation systems for larger emissions reduction and further energy savings. Results show that existing crude oil installations can save up to 21% in energy and 22% in emissions, when the process conditions are optimized. Additionally, by integrating a gas turbine, the total emissions can be reduced further by 48%. Internal heat-integrated columns can be a good alternative to conventional heat pump and other energy intensive close boiling mixtures separations. Energy savings can reach up to 100% with respect to reboiler heat requirements. Emissions of these configurations are cut down by up to 83%, compared to conventional units, and by 36%, with respect to heat pump alternatives. Importantly, cost savings and more profit are gained in parallel to emissions minimization. PMID:16190250

  13. Cytokine adsorbing columns.

    PubMed

    Taniguchi, Takumi

    2010-01-01

    Sepsis induces the activation of complement and the release of inflammatory cytokines such as TNF-alpha and IL-1beta. The inflammatory cytokines and nitric oxide induced by sepsis can decrease systemic vascular resistance, resulting in profound hypotension. The combination of hypotension and microvascular occlusion results in tissue ischemia and ultimately leads to multiple organ failure. Recently, several experimental and clinical studies have reported that treatment for adsorption of cytokines is beneficial during endotoxemia and sepsis. Therefore, the present article discusses cytokine adsorbing columns. These columns, such as CytoSorb, CYT-860-DHP, Lixelle, CTR-001 and MPCF-X, the structures of which vary significantly, have excellent adsorption rates for inflammatory cytokines such as TNF-alpha, IL-1beta, IL-6 and IL8. Many studies have demonstrated that treatment with cytokine adsorbing columns has beneficial effects on the survival rate and inflammatory responses in animal septic models. Moreover, several cases have been reported in which treatment with cytokine adsorbing columns is very effective in hemodynamics and organ failures in critically ill patients. Although further investigations and clinical trials are needed, in the future treatment with cytokine adsorbing columns may play a major role in the treatment of hypercytokinemia such as multiple organ failure and acute respiratory distress syndrome. PMID:20473001

  14. Polymer-coated fibrous materials as the stationary phase in packed capillary gas chromatography.

    PubMed

    Saito, Yoshihiro; Tahara, Ai; Imaizumi, Motohiro; Takeichi, Tsutomu; Wada, Hiroo; Jinno, Kiyokatsu

    2003-10-15

    Synthetic polymer filaments have been introduced as the support material in packed capillary gas chromatography (GC). The filaments of the heat-resistant polymers, Zylon, Kevlar, Nomex, and Technora, were longitudinally packed into a short fused-silica capillary, followed by the conventional coating process for open-tubular GC columns. The separation of several test mixtures such as n-alkylbenzenes and n-alkanes was carried out with these polymer-coated fiber-packed capillary columns. With the coating by various polymeric materials on the surface of these filaments, the retentivity was significantly improved over the parent fiber-packed column (without polymer coating) as well as a conventional open-tubular capillary of the same length. The results demonstrated a good combination of Zylon as the support and poly(dimethylsiloxane)-based materials as the coating liquid-phase for the successful GC separation of n-alkanes and polycyclic aromatic hydrocarbons (PAHs), while successful applications for other separations such as poly(ethylene glycol) coating for the separation of alcohols were also obtained. From the results it has been suggested that the selectivity of the fiber-packed column could be tuned by selecting different coating materials, indicating the promising possibility for a novel usage of fine fibrous polymers as the support material that can be combined with newly synthesized coating materials specially designed for particular separations. Taking advantage of good thermal stability of the fibers, the column temperature could be elevated to higher than 350 degrees C with the combination of a short metallic capillary. PMID:14710834

  15. Administration of distillate thyme leaves into the diet of Segureña ewes: effect on lamb meat quality.

    PubMed

    Nieto, G; Bañón, S; Garrido, M D

    2012-12-01

    The effect of including thyme by-products from the distillation industry into the diet of pregnant ewes on the final quality of lamb meat was evaluated during meat storage in modified atmosphere. A total of 36 Segureña ewes were randomly assigned to three homogeneous groups. One group was fed a basal diet (BD) as control (C), whereas the diet of the other two groups was modified by substituting 10% (T 1) and 20% (T 2) of the BD with pellets made from 50% barley and 50% distilled thyme leaves (DTL). Meat spoilage (total viable, psychrotroph (PSY), moulds and yeasts, Enterobacteriaceae and lactic acid bacteria), thiobarbituric acid reactive substances (TBARS), colour (CIELab coordinates, metmyoglobin) and sensory characteristics of fresh lamb meat packed in modified atmosphere packaging (70% O2 : 30% CO2) were analysed after storage at 0, 7, 14 and 21 days. In general, the DTL-containing diet inhibited lipid and pigment oxidation in fresh lamb meat. Lower PSY counts and content of secondary oxidation product (TBARS) as a result of adding DTL to the ewe diet, whereas surface redness (a* values) was significantly higher on days 7 and 14. It can be concluded that thyme by-products from the distillation industry could be used as a source of natural antioxidant and antimicrobial in the feed for ewes. PMID:23031660

  16. Preparation and evaluation of molecularly imprinted polymer liquid chromatography column for the separation of Cathine enantiomers

    PubMed Central

    Balamurugan, Krishnamoorthy; Gokulakrishnan, Kannan; Prakasam, Tangirala

    2011-01-01

    In this study molecular imprinting technology was employed to prepare a specific affinity sorbent for the resolution of Cathine, a chiral drug product. The molecularly imprinted polymer (MIP) was prepared by non-covalent molecular imprinting with either (+) or (?)-Cathine (threo-2-amino-1-hydroxy-1-phenyl propane; norpseudoephedrine) as the template. Methacrylic acid and ethylene glycol di-methacrylate were copolymerized in the presence of the template molecule. The bulk polymerization was carried out in chloroform with 2,2?-azobisisobutyronitrile as the initiator, at 5 °C and under UV radiation. The resulting MIP was ground into powders, which were slurry packed into analytical columns. After removal of template molecules, the MIP-packed columns were found to be effective for the resolution of (±)-Cathine racemates. The separation factor for the enantiomers ranged between 1.5 and 2.4 when the column was packed with MIP prepared with (+)-Cathine as the template. A separation factor ranging from 1.6 to 2.9 could be achieved from the column packed with MIP, prepared with (?)-Cathine as the template. Although the separation factor was higher with that previously obtained from reversed-phase column chromatography following derivatization with a chiral agent, elution peaks were broader due to the heterogeneity of binding sites on MIP particles and the possible non-specific interaction. PMID:23960776

  17. Conversion of carboxylate salts to carboxylic acids via reactive distillation

    E-print Network

    Williamson, Shelly Ann

    2000-01-01

    on the conversion of the carboxylate salts produced via fermentation into their corresponding acids via reactive distillation. The primary objective is to determine the optimal operating conditions of the distillation. A secondary objective is to optimize...

  18. 76 FR 9079 - Revision of Distilled Spirits Plant Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-16

    ...incorporates plain language principles in order to improve the clarity...General Distilled spirits taxation is a specialized area of Federal...internal revenue or customs taxation of spirits, wines...This subpart covers the taxation of distilled spirits and...

  19. 40 CFR 1065.703 - Distillate diesel fuel.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...1065.703 Distillate diesel fuel. (a) Distillate diesel fuels for testing must be clean and bright, with pour and cloud points adequate for proper engine operation. (b) There are three grades of #2 diesel fuel specified for use as...

  20. 40 CFR 1065.703 - Distillate diesel fuel.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...1065.703 Distillate diesel fuel. (a) Distillate diesel fuels for testing must be clean and bright, with pour and cloud points adequate for proper engine operation. (b) There are three grades of #2 diesel fuel specified for use as...

  1. 40 CFR 1065.703 - Distillate diesel fuel.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...1065.703 Distillate diesel fuel. (a) Distillate diesel fuels for testing must be clean and bright, with pour and cloud points adequate for proper engine operation. (b) There are three grades of #2 diesel fuel specified for use as...

  2. 40 CFR 1065.703 - Distillate diesel fuel.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...1065.703 Distillate diesel fuel. (a) Distillate diesel fuels for testing must be clean and bright, with pour and cloud points adequate for proper engine operation. (b) There are three grades of #2 diesel fuel specified for use as...

  3. Chemical composition of distillers grains, a review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In recent years, increasing demand for ethanol as a fuel additive and decreasing dependency on fossil fuels have resulted in a dramatic increase in the amount of grains used for ethanol production. Dry-grind is the major process, resulting in distillers dried grains with solubles (DDGS) as a major ...

  4. Naphthenic acid corrosion in crude distillation units

    SciTech Connect

    Piehl, R.L.

    1988-01-01

    This paper summarizes corrosion experience in crude distillation units processing highly naphthenic California crude oils. Correlations have been developed relating corrosion rates to temperature and total acid number. There is a threshold acid number in the range of 1.5 to 2 mg KOH/g below which corrosion is minimal. High concentrations of hydrogen sulfide may raise this threshold value.

  5. STEAM DISTILLATION OF POLONIUM COMPOUND WITH DIPHENYLCARBAZIDE

    Microsoft Academic Search

    H Mabuchi

    1963-01-01

    Trace amounts of polonium can readily be steam distilled from 0.1 to 0.5 ; N nitric acid as the diphenylcarbazide complex. Chloride ion lowers the ; efficiency of the process. The separation is suitable for isoiating Po from ; radium-D-E-F mixtures. (auth);

  6. azeotropic batch distillation with heterogeneous en trainers

    Microsoft Academic Search

    I. Rodriguez-Donis; J. Acosta-Esquijarosa; V. Gerbaud; E. Pardillo-Fondevila

    In this article, a systematic study of the separati on of the n-hexane - ethyl acetate mixture with an entrainer by heterogeneous azeotropic batch distillation is performed. Based upon the thermodynamic behaviour of the ternary mixtures, potential entrainers partially miscible with one or two original azeotropic compon ents are chosen. In all cases, the entrainer adds a heterogeneous binary or

  7. Feasibility study of heterogeneous batch extractive distillation

    Microsoft Academic Search

    Ivonne Rodríguez-Donis; Viktória Varga; Vincent Gerbaud; Zoltán Lelkes; Endre Rév; Zsolt Fonyó; Xavier Joulia

    2005-01-01

    Feasibility of batch hetero geneous extractive distillation is studied in the case where the heterogeneous azeotrope formed with the entrainer is not the most volatile point in the system. The composition profile maps based feasibility methodology is extended to this case, and demonstrated on the test problem of separating water from acetonitrile with butyl acetate as entrainer.Whether the process is

  8. Feasibility Study of Heterogeneous Batch Extractive Distillation

    Microsoft Academic Search

    Ivonne Rodríguez-Donis; Viktória Varga; Vincent Gerbaud; Zoltán Lelkes

    Feasibility of batch heterogeneous extractive distillation is studied in the case where the heterogeneous azeotrope formed with the entrainer is not the most volatile point in the system. The composition profile maps based feasibility methodology is extended to this case, and demonstrated on the test problem of separating water from acetonitrile with butyl acetate as entrainer. Whether the process is

  9. PPMCSA Presentation on Winter Distillate Outlook

    NSDL National Science Digital Library

    This presentation on the Winter Distillate Outlook was created for the PPMCSA Meeting and Trade Show of this year. It gives basic information and forecasts on the prices of a variety of energy sources through a collection of slides and accompanying notes.

  10. Membrane-distillation desalination: Status and potential

    Microsoft Academic Search

    A. M. Alklaibi; Noam Lior

    2005-01-01

    This paper presents an assessment of membrane distillation (MD) based on the available state of the art and on ourpreliminary analysis. The process has many desirable properties such as low energy consumption, ability to use low temperature heat, compactness, and perceivably more immunity to fouling than other membrane processes. Within the tested range, the operating parameters of conventional MD configurations

  11. Desalination by Membrane Distillation: A Parametric Study

    Microsoft Academic Search

    Fawzi A. Banat; Jana Simandl

    1998-01-01

    Membrane distillation was investigated as a possible technique for desalination. An air-gap module with built-in Condensing surface was used for conducting experiments on polyvinylidene fluoride flat membrane sheets. The feed stream tested was artificial seawater. The quality of the permeate, quantified by conductivity measurements, and the permeate flux were monitored as the feed temperature, feed flow rate, cooling temperature, and

  12. Seawater desalination by direct contact membrane distillation

    Microsoft Academic Search

    S. T. Hsu; K. T. Cheng; J. S. Chiou

    2002-01-01

    Membrane fouling still posts as one of the major obstacles in membrane distillation (MD). This is why the MD approach still cannot successfully compete with other conventional seawater desalination methods. In this study, both the NaCl solution and real seawater are used as the feed of MD processes to investigate the differences in permeate flux, product water quality and membrane

  13. Abstracts -1 Distill for CASP11

    E-print Network

    Pollastri, Gianluca

    that everything in our pipeline (except BLAST and the software to blow C traces into full-atom models) is in house in the first stage. Methods Distill runs 3 rounds of PSI-BLAST against a 90% redundancy reduced Uni category. Inputs for map prediction are: the sequence; MSA; PSI-BLAST, SAMD and SAMD templates. That is

  14. An improved model for multiple effect distillation

    Microsoft Academic Search

    Karan H. Mistry; Mohamed A. Antar; John H. Lienhard V

    2012-01-01

    Increasing global demand for fresh water is driving research and development of advanced desalination technologies. As a result, a detailed model of multiple effect distillation (MED) is developed that is flexible, simple to implement, and suitable for use in optimization of water and power cogeneration systems. The MED system is modeled in a modular method in which each of the

  15. Multieffect distillation plants: state of the art

    Microsoft Academic Search

    M. Al-Shammiri; M. Safar

    1999-01-01

    The multi-effect distillation (MED) process is the oldest process in desalination. References and patents have existed since 1840, more than 150 years ago. Vertical tubes, horizontal tubes and different types of submerged tubes have been commercialized and were used until 1960 when multi-stage flash (MSF) dominated the desalination market. MSF plants are presently the most widely used and are considered

  16. [Electroflotation packing of mycelial wastes].

    PubMed

    Nikolaev, V B; Karpukhin, V F; Zav'ialova, E V; Faingol'd, Z L

    1989-04-01

    Data on testing a pilot plant for electroflotative packing of mycelial wastes are presented. Both the mycelial wastes and their mixtures were used. Concentration of dry substances raged from 3.5 to 131 g/l. The process was performed with varying flow density and consumption rate of the liquid supplied to the plant. Insoluble magnetite and ruthenium oxide anodes were used. The moister content in the packed phase was 81-97.5 per cent. The study provided specification of the process technological parameters and investigation of the flotator hydroulic characteristics. PMID:2751387

  17. Cylinder valve packing nut studies

    SciTech Connect

    Blue, S.C. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

    1991-12-31

    The design, manufacture, and use of cylinder valve packing nuts have been studied to improve their resistance to failure from stress corrosion cracking. Stress frozen photoelastic models have been analyzed to measure the stress concentrations at observed points of failure. The load effects induced by assembly torque and thermal expansion of stem packing were observed by strain gaging nuts. The effects of finishing operations and heat treatment were studied by the strain gage hole boring and X-ray methods. Modifications of manufacturing and operation practices are reducing the frequency of stress corrosion failures.

  18. Construction and operation of a flash distillation apparatus

    E-print Network

    Knezevich, Milan

    1940-01-01

    , Calibration Data of Orifioe ~, i, . ~ ~ ~ . ~ ~ . ~ 13 III. Equilibrium Data of Ethanol-Eater Mixtures . ~ * ~ ~ , 17 IV, . Flash Vaporieation Data of Ethanol Hater hIlxtures& + , 18 VI ~ Hempel Distillation of Oklahoma City Crude ~ . . . Flash... Vaporiration of Oklahoma City Crude ~ . ~ 21 22 VII' Hempel Distillations of Flash Distillates of Oklahoma City Crude . ~ ~ ~ ~ ~ ~ ~ i ~ ~ ~ ~ ~ ~ ~ ~ 24 VIII+ Hompel Distillations of Flash Residuums of Oklahoma City Crude ~ ~ ~ ~ ~ i ~ ~ o...

  19. Gas chromatographic separation of isomeric benzene derivatives using molecular sieves, combined with partition columns

    Microsoft Academic Search

    T. G. Andronikashvili; L. G. Eprikashvili; N. V. Pirtskhalava; G. N. Kirov; V. P. Valtchev

    1994-01-01

    The possibility of using short gas chromatographic columns packed with different molecular sieves (silicalite and aluminophosphates), showing definite selectivity to para-isomeric compounds, in series with columns containing a liquid stationary phase was investigated. The molecular sieves were of different origin, while 1,2,3-tris (2-cyanoethoxy)propane (TCEP) and polyethylene glycol adipate (PEGA) were used as the liquid stationary phase. Ortho-, meta- and para-isomers

  20. Improved micromachined column design and fluidic interconnects for programmed high-temperature gas chromatography separations.

    PubMed

    Gaddes, David; Westland, Jessica; Dorman, Frank L; Tadigadapa, Srinivas

    2014-07-01

    This work focuses on the development and experimental evaluation of micromachined chromatographic columns for use in a commercial gas chromatography (GC) system. A vespel/graphite ferrule based compression sealing technique is presented using which leak-proof fluidic interconnection between the inlet tubing and the microchannel was achieved. This sealing technique enabled separation at temperatures up to 350°C on a ?GC column. This paper reports the first high-temperature separations in microfabricated chromatographic columns at these temperatures. A 2m microfabricated column using a double Archimedean spiral design with a square cross-section of 100?m×100?m has been developed using silicon microfabrication techniques. The microfabricated column was benchmarked against a 2m 100?m diameter commercial column and the performance between the two columns was evaluated in tests performed under identical conditions. High temperature separations of simulated distillation (ASTM2887) and polycyclic aromatic hydrocarbons (EPA8310) were performed using the ?GC column in temperature programmed mode. The demonstrated ?GC column along with the high temperature fixture offers one more solution toward potentially realizing a portable ?GC device for the detection of semi-volatile environmental pollutants and explosives without the thermal limitations reported to date with ?GC columns using epoxy based interconnect technology. PMID:24866564

  1. Dense crystalline dimer packings of regular tetrahedra

    E-print Network

    Elizabeth R. Chen; Michael Engel; Sharon C. Glotzer

    2010-07-25

    We present the densest known packing of regular tetrahedra with density phi = 4000/4671 = 0.856347... Like the recently discovered packings of Kallus et al. [arXiv:0910.5226] and Torquato-Jiao [arXiv:0912.4210], our packing is crystalline with a unit cell of four tetrahedra forming two triangular dipyramids (dimer clusters). We show that our packing has maximal density within a three-parameter family of dimer packings. Numerical compressions starting from random configurations suggest that the packing may be optimal at least for small cells with up to 16 tetrahedra and periodic boundaries.

  2. Columns in Clay

    ERIC Educational Resources Information Center

    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…

  3. Nuclear fuel column retainer

    Microsoft Academic Search

    D. F. MacMillan; B. A. Smith; R. P. Dubrule

    1976-01-01

    A description is given of a barrier member fixed in the end of a fuel column retaining spring to prevent contact between the retaining spring and the adjacent end plug of the fuel element whereby contamination of the weld between the cladding tube and end plug with retaining spring material is avoided. 12 claims, 5 drawing figures.

  4. CHEM333: Lab Experiment 3: Distillation and Gas Chromatography

    E-print Network

    Taber, Douglass

    to measure the volume of distillate, set up test tubes in a test tube rack. Record the vapor temperature when the distillation pot to dryness. Seal the vials tightly to prevent evaporation before you run your GC's. #12;Dispose of your three fractions and the residue from your distillation pot in the appropriate waste

  5. Engineering-scale distillation of cadmium for actinide recovery

    Microsoft Academic Search

    B. R. Westphal; J. C. Price; D. Vaden; R. W. Benedict

    2007-01-01

    During the recovery of actinide products from spent nuclear fuel, cadmium is separated from the actinide products by a distillation process. Distillation occurs in an induction-heated furnace called a cathode processor capable of processing kilogram quantities of cadmium. Operating parameters have been established for sufficient recovery of the cadmium based on mass balance and product purity. A cadmium distillation rate

  6. Distilling Free-Form Natural Laws from Experimental Data

    E-print Network

    Fernandez, Thomas

    Distilling Free-Form Natural Laws from Experimental Data Michael Schmidt1 and Hod Lipson2 precise and powerful, but automated processes for distilling this data into knowledge in the form relations, thus helping distill data into scientific knowledge. Symbolic regression (10) is an established

  7. 27 CFR 28.280 - Distilled spirits and wines.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Distilled spirits and wines. 28.280 Section 28.280 Alcohol...Aircraft § 28.280 Distilled spirits and wines. When an airline desires to withdraw distilled spirits or wines from its stock being held at...

  8. Packing tube assembly for pumping wells

    SciTech Connect

    Towner, G.F.; Carter, C.A.

    1987-09-22

    A packing tube assembly for replacing a conventional stuffing box is described. The packing tube assembly comprising: a packing tube; a rod adaptor adapted to be coupled between the polished rod and the sucker rod string and adapted to extend throughout the packing tube when positioned therein; compressible packing means on the rod adaptor adapted to provide a seal between the rod adaptor and the packing tube when the rod adaptor is in position within the packing tube; stabilizing means on the rod adaptor adapted to engage the packing tube to stabilize the rod adaptor within the packing tube during operation; and a mounting bushing connected to the top of the packing tube and adapted to be threaded into the pumping tee to secure the packing tube position within the production tubing string. A method of converting a conventional stuffing box-equipped pumping well to a packing tube-equipped well is described. It consists of: disconnecting the polished rod of the pumping well from the sucker rod string while suspending the sucker rod string within the well by the use of slips; unthreading the conventional stuffing box from the pumping tee of the well and removing the stuffing box; attaching the polished rod to the upper end of a rod adaptor of a packing tube assembly, inserting the rod adaptor with the polished rod attached into the packing tube of the packing tube assembly; aligning the packing tube assembly with the sucker rod string; connecting the lower end of the rod adaptor to the sucker rod string; removing the slips and lowering the packer tube assembly through the pumping tee; and connecting the upper end of the packing tube to the pumping tee.

  9. Separation of mycotoxins, polycyclic aromatic hydrocarbons, quinones, and heterocyclic compounds on cyclodextrin bonded phases: an alternative LC packing

    SciTech Connect

    Armstrong, D.W.; Alak, A.; De Mond, W.; Hinze, W.L.; Riehl, T.E.

    1985-01-01

    ..beta..-Cyclodextrin and gamma-cyclodextrin chiral bonded phases were previously shown to be useful in the separation of enantiomers, diastereomers and structural isomers. In this work it is demonstrated that these stationary phases are also useful in more routine separations. As such, they provide an alternative to the popular reverse phase packings. Because the selectivity of cyclodextrin packings is often unique they can be used to compliment conventional columns, particularly when separating complex mixtures where peak overlap is a problem. The separation of several important classes of compounds is used to demonstrate the general utility of this packing.

  10. 48 CFR 211.272 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...272 Alternate preservation, packaging, and packing. Use the provision...211-7004, Alternate Preservation, Packaging, and Packing, in solicitations which include military preservation, packaging, or packing specifications...

  11. 48 CFR 211.272 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...272 Alternate preservation, packaging, and packing. Use the provision...211-7004, Alternate Preservation, Packaging, and Packing, in solicitations which include military preservation, packaging, or packing specifications...

  12. 48 CFR 211.272 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...272 Alternate preservation, packaging, and packing. Use the provision...211-7004, Alternate Preservation, Packaging, and Packing, in solicitations which include military preservation, packaging, or packing specifications...

  13. Wiggling Worms ClassPack

    NSDL National Science Digital Library

    2010-04-23

    Using More Picture-Perfect Science Lessons: Using Children's Books to Guide Inquiry, K-4 in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatche

  14. Loco Beans ClassPack

    NSDL National Science Digital Library

    2010-04-22

    Using More Picture-Perfect Science Lessons: Using Children's Books to Guide Inquiry, K-4 in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatche

  15. Roller Coasters ClassPack

    NSDL National Science Digital Library

    2010-04-25

    Using More Picture-Perfect Science Lessons: Using Children's Books to Guide Inquiry, K-4 in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatche

  16. Imaginative Inventions ClassPack

    NSDL National Science Digital Library

    2010-04-25

    Using More Picture-Perfect Science Lessons: Using Children's Books to Guide Inquiry, K-4 in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatche

  17. Ecology and Energy Action Pack.

    ERIC Educational Resources Information Center

    McDonald's Corp., Oak Brook, IL.

    One of five McDonald's Action Packs, these elementary school-level instructional materials are for use as an introduction to existing units of study, supplements to a textbook, or a source of special projects for environmental education. Contents include these six units: Make Your Own Ecology Mini-spinner, Let's Look at a Food Chain, Drip the…

  18. Students & Mental Health Resource Pack

    E-print Network

    Stevenson, Mark

    Students & Mental Health Resource Pack Produced by - www.rethink.org/at-ease/ SHEFFIELD EARLY is severe mental illness? 1.4 Treatment and prognosis What is mental health awareness? 2.1 Introduction 2 for students with experience of mental health problems 5.1 Introduction 5.2 Pre-entry guidance for students 5

  19. Cs diffusion in local Taiwan laterite with different solution concentration, pH and packing density.

    PubMed

    Wang, Tsing-Hai; Li, Ming-Hsu; Teng, Shi-Ping

    2008-09-01

    In this work we used an "in-diffusion" method to study the effects of pH, solution concentration and packing density on Cs diffusion by packing local Taiwan laterite (LTL) into modified capillary columns with 5mm diameter. These packed columns were first pre-equilibrated with synthetic groundwater (GW) for 3 weeks. The diffusion experiments were then carried out at ambient condition for 2 weeks. Our experimental results showed that the Cs diffusion profile fits Fick's second law very well in given experimental conditions, indicating the validity of modified capillary column method. Generally speaking, Cs diffusion in LTL decreases as the pH increases and as Cs concentration decreases. The apparent diffusion coefficient (D(a)) increases from 5.52 x 10(-12) (10(-7)M) to 2.18 x 10(-11) (10(-3)M)m(2)/s, while the effective diffusion coefficient (D(e)) shows slight variation as the Cs concentration changes. Both the derived D(a) and D(e) values decrease as the pH increases, implying that the diffusion mechanisms of Cs nuclide in alkaline and acid environment are different. In addition, our results show that Cs diffusion is unaffected by the given packing density, indicating the interlaminary space is not the major determinant of Cs adsorption and diffusion in LTL. PMID:18321721

  20. 11. TIMBER COLUMN AND CAST IRON COLUMN CAP IN FIFTH ...

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

    11. TIMBER COLUMN AND CAST IRON COLUMN CAP IN FIFTH FLOOR WAREHOUSE SPACE. VIEW TO SOUTHWEST. - Commercial & Industrial Buildings, Becker-Hazelton Company Warehouse, 280 Iowa Street, Dubuque, Dubuque County, IA

  1. 7 CFR 917.13 - Pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 917.13 Pack. Pack means the specific...

  2. 7 CFR 917.13 - Pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 917.13 Pack. Pack means the specific...

  3. 7 CFR 917.13 - Pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 917.13 Pack. Pack means the specific...

  4. 7 CFR 917.13 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 917.13 Pack. Pack means the specific...

  5. 7 CFR 958.16 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ONIONS GROWN IN CERTAIN DESIGNATED COUNTIES IN IDAHO, AND MALHEUR...Definitions § 958.16 Pack. Pack means a quantity of onions in any type of container and which falls within specific...

  6. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling...internal quality, and external appearance and condition of hazelnuts packed in accordance with any of the pack specifications...

  7. 7 CFR 917.13 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 917.13 Pack. Pack means the specific arrangement, size,...

  8. 7 CFR 924.16 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE FRESH PRUNES GROWN IN DESIGNATED COUNTIES IN WASHINGTON AND IN UMATILLA COUNTY, OREGON Order Regulating Handling Definitions § 924.16 Pack. Pack means the specific...

  9. 7 CFR 51.1311 - Packing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...shall not be allowed in any standard pack. When wrapped, each pear shall be fairly well enclosed by its individual wrapper. (d) Pears packed in round stave bushel baskets, tubs, or in barrels shall be ring...

  10. 7 CFR 51.1270 - Packing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...bridge shall not be allowed in any standard pack. When wrapped, each pear shall be fairly well enclosed by its individual wrapper. (d) Pears packed in round stave bushel baskets, tubs or in barrels shall be ring...

  11. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack is a...

  12. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack...

  13. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack...

  14. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack...

  15. Calculational procedure for multicomponent distillation columns with side-stream-strippers

    E-print Network

    Dickey, Billy Ray

    1962-01-01

    ' rapo 's mt' +' s? h?: djq?4 p?r og ~ . t + ~u o~ 'ys w, uinyd ' tg a oq dr-, g b* trente! &- "h a'. qw e. v ' s '' 0 ths dis", " l'::t a~mar tiana. ol! ct. ua?storm, ri . rc "c 1";is eau given r . +hs . a':1st" cn a~ the ~rotated Wth'. mes" ra+e frw...CALG!fLATI )MAL Pf';)GP&P 'f', !G?, , C, L'IG1VPGf F, "fT fu. ;TrLLAII f GGLffMMS , 'r i RII!E ~&?PAP 8?~?P';ff" A Tfiesis Billy ffay Diczey '. hai+ted . o th ~ f:raduate Bc!" ool o" the Agricultural and Mechanical College oT Texas...

  16. Calculational procedure for multicomponent distillation columns with side-stream-strippers 

    E-print Network

    Dickey, Billy Ray

    1962-01-01

    , nificant, a co, , lets set of p . rtial . . iolar ent. ial . ics may . e calcula=edi 'cy "'qu tions (1), ind (la), ?nii anth:il y biil, inca - usec t'iroughout thc dictil'ation co i uun to establis!i corr ected vai?r and liquid rates. The cor. ected va d...

  17. Solution of Multicomponent distillation problems for conventional and complex columns at unsteady state operation

    E-print Network

    Pendon, Gregorio Parrenas

    1966-01-01

    that represents a component-material balance is t +At t n (v. . t t, - v?- t, . )dt = u . j+l, i j-1 ji ji ji u t t6t tn J1 n (4- 2) By use of the mean value theorem of integral calculus (5), the integral that appears in Equation (4-2) may be stated... exactly in terms of its mean value as follows: 21 t +At n t t v. . +R. , -v. . t. . dt= v, . +t, , -v. , R. . gt j+l, i j-l, i ji ji j L jul, i j-l, i ji jiJ m n or in terms of functional notation, r t +Et udt = v 11t t n (4 4) If the mean...

  18. Solution of Multicomponent distillation problems for conventional and complex columns at unsteady state operation 

    E-print Network

    Pendon, Gregorio Parrenas

    1966-01-01

    . Storey, and J. A. Challis, Proc. of the First International Congress of the I. F. A. C, , Vol. IV, 303 (London, England: Butte rworths, 1961). 17. dt t, R. G. , N tMtdd 1 Et* d~E (Englewood Cliffs, N. J. : Prentice Hall, Inc. , 1961). 18. Thiele, E... gratitude is extended to his parents, Mr. and Mrs. David Pendon, to whom this work is dedicated. 111 TABZ E OF CONTENTS ACKNOWLEDGMENTS LIST OF TABLES LIST OF FIGURES . Page V1 CHAPTER I. INTRODUCTION II. SURVEY OF THE LITERATURE III. MODIFIED e...

  19. Microcosm and Column Studies on the Biodegradation of Methyl TertButyl Ether (MTBE) in Soil-Water Systems

    Microsoft Academic Search

    Marcia Morales; Marc A. Deshusses; Sergio Revah

    Microcosms and column experiments were carried out using soil and groundwater from a MTBE contaminated site or using distilled water amended with mineral salts. The biodegradation of MTBE was tested under aerobic and anaerobic conditions with an initial MTBE concentration of 25 mg\\/L. The water to soil ratio in the microcosm experiments was 1:2 by mass and the inoculum size

  20. On the kinetics of pack aluminization

    NASA Technical Reports Server (NTRS)

    Gupta, B. K.; Sarkhel, A. K.; Seigle, L. L.

    1975-01-01

    A theory of pack aluminization has been formulated by combining gaseous and solid-state diffusion rates. This theory relates the surface composition of the coating and therefore, in principle, the phase morphology and the growth rate of the coating, to pack operating parameters such as pack aluminum density, type of activator, temperature and others. Experimental data on the aluminization of unalloyed nickel in pure aluminum packs obtained to date are in good agreement with the predictions of the theory.

  1. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... United States Standards for Grades of Peaches Standard Pack § 51.1217 Standard...Each package shall be packed so that the peaches in the shown face shall be reasonably...the contents of the package. (b) Peaches packed in U.S. Standard bushel...

  2. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... United States Standards for Grades of Peaches Standard Pack § 51.1217 Standard...Each package shall be packed so that the peaches in the shown face shall be reasonably...the contents of the package. (b) Peaches packed in U.S. Standard bushel...

  3. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... United States Standards for Grades of Peaches Standard Pack § 51.1217 Standard...Each package shall be packed so that the peaches in the shown face shall be reasonably...the contents of the package. (b) Peaches packed in U.S. Standard bushel...

  4. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... United States Standards for Grades of Peaches Standard Pack § 51.1217 Standard...Each package shall be packed so that the peaches in the shown face shall be reasonably...the contents of the package. (b) Peaches packed in U.S. Standard bushel...

  5. Microfluidic chip for peptide analysis with an integrated HPLC column, sample enrichment column, and nanoelectrospray tip.

    PubMed

    Yin, Hongfeng; Killeen, Kevin; Brennen, Reid; Sobek, Dan; Werlich, Mark; van de Goor, Tom

    2005-01-15

    Current nano-LC/MS systems require the use of an enrichment column, a separation column, a nanospray tip, and the fittings needed to connect these parts together. In this paper, we present a microfabricated approach to nano-LC, which integrates these components on a single LC chip, eliminating the need for conventional LC connections. The chip was fabricated by laminating polyimide films with laser-ablated channels, ports, and frit structures. The enrichment and separation columns were packed using conventional reversed-phase chromatography particles. A face-seal rotary valve provided a means for switching between sample loading and separation configurations with minimum dead and delay volumes while allowing high-pressure operation. The LC chip and valve assembly were mounted within a custom electrospray source on an ion-trap mass spectrometer. The overall system performance was demonstrated through reversed-phase gradient separations of tryptic protein digests at flow rates between 100 and 400 nL/min. Microfluidic integration of the nano-LC components enabled separations with subfemtomole detection sensitivity, minimal carryover, and robust and stable electrospray throughout the LC solvent gradient. PMID:15649049

  6. Enzymatic methylation of canola oil deodorizer distillate

    Microsoft Academic Search

    Suresh Ramamurthi; Prakash R. Bhirud; Alan R. McCurdy

    1991-01-01

    Methylation of canola oil deodorizer distillate catalyzed by a nonspecific lipase was investigated. The conversion of fatty\\u000a acids to methyl esters has been optimized by using a statistical design. Up to 96.5% conversion of fatty acids to their methyl\\u000a esters has been achieved without the aid of vacuum or any water-removing agent. The effects of temperature, ratio of the reactants

  7. Nucleic acid chromatography: substitute solid support material for RPC-5 columns

    SciTech Connect

    Flanagan, J.M.; Fujimura, R.K.; Jacobson, K.B.

    1986-03-01

    Chromatography of tRNA and DNA fragments on columns of reverse-phase 5 (RPC-5) exchange material has been widely employed for analytical and preparative studies. The Plaskon bead that formed the solid support on which a quaternary amine was absorbed is no longer commercially available. A Voltalef bead is available and provides similar, though not identical, chromatograms for Asp-tRNA, Ser-tRNA, and certain DNA fragments. Procedures are described for preparation of the column packing and for long-term operation of the column.

  8. Continuous-flow stereoselective organocatalyzed Diels-Alder reactions in a chiral catalytic "homemade" HPLC column.

    PubMed

    Chiroli, Valerio; Benaglia, Maurizio; Cozzi, Franco; Puglisi, Alessandra; Annunziata, Rita; Celentano, Giuseppe

    2013-07-19

    Continuous-flow organocatalyzed Diels-Alder reactions have been performed with excellent enantioselectivity for the first time in a chiral "homemade" HPLC column, packed with silica on which a MacMillan catalyst has been supported by a straightforward immobilization procedure. The versatility of the system was also proven by running with the same column continuous-flow stereoselective reactions with three different substrates, showing that the catalytic reactor may efficiently work in continuo for more than 150 h; the regeneration of the HPLC column was also demonstrated, allowing to further extend the activity of the reactor to more than 300 operating hours. PMID:23808663

  9. Force fluctuations in bead packs.

    PubMed

    Liu, C H; Nagel, S R; Schecter, D A; Coppersmith, S N; Majumdar, S; Narayan, O; Witten, T A

    1995-07-28

    Experimental observations and numerical simulations of the large force inhomogeneities present in stationary bead packs are presented. Forces much larger than the mean occurred but were exponentially rare. An exactly soluble model reproduced many aspects of the experiments and simulations. In this model, the fluctuations in the force distribution arise because of variations in the contact angles and the constraints imposed by the force balance on each bead in the pile. PMID:17842361

  10. Adhesive Loose Packings of Small Particles

    E-print Network

    Wenwei Liu; Shuiqing Li; Adrian Baule; Hernán A. Makse

    2014-10-08

    We explore adhesive loose packings of dry small spherical particles of micrometer size using 3D discrete-element simulations with adhesive contact mechanics. A dimensionless adhesion parameter ($Ad$) successfully combines the effects of particle velocities, sizes and the work of adhesion, identifying a universal regime of adhesive packings for $Ad>1$. The structural properties of the packings in this regime are well described by an ensemble approach based on a coarse-grained volume function that includes correlations between bulk and contact spheres. Our theoretical and numerical results predict: (i) An equation of state for adhesive loose packings that appears as a continuation from the frictionless random close packing (RCP) point in the jamming phase diagram; (ii) The existence of a maximal loose packing point at the coordination number $Z=2$ and packing fraction $\\phi=1/2^{3}$. Our results highlight that adhesion leads to a universal packing regime at packing fractions much smaller than the random loose packing, which can be described within a statistical mechanical framework. We present a general phase diagram of jammed matter comprising frictionless, frictional, adhesive as well as non-spherical particles, providing a classification of packings in terms of their continuation from the spherical frictionless RCP.

  11. Exogenous factors contributing to column bed heterogeneity: Part 1: Consequences of 'air' injections in liquid chromatography.

    PubMed

    Samuelsson, Jörgen; Fornstedt, Torgny; Shalliker, Andrew

    2015-08-01

    It has been shown that not only the packing homogeneity, but also factors external to the column bed, such as, frits and distributors can have important effects on the column performance. This current communication is the first in a series focusing on the impact of exogenous factors on the column bed heterogeneity. This study is based on several observations by us and others that chromatographic runs often, for technical reasons, include more or less portions of air in the injections. It is therefore extremely important to find out the impact of air on the column performance, the reliability of the results derived from analyses where air was injected, and the effect on the column homogeneity. We used a photographic approach for visualising the air transport phenomena, and found that the air transport through the column is comprised of many different types of transport phenomena, such as laminal flow, viscous fingering like flows, channels and bulbs, and pulsations. More particularly, the air clouds within the column definitely interact in the adsorption, i.e. mobile phase adsorbed to the column surface is displaced. In addition, irrespective of the type of air transport phenomena, the air does not penetrate the column homogeneously. This process is strongly flow dependent. In this work we study air transport both in an analytical scale and a semi-prep column. PMID:26118806

  12. Kinetics of pack aluminization of nickel

    NASA Technical Reports Server (NTRS)

    Seigle, L. L.; Gupta, B. K.; Shankar, R.; Sarkhel, A. K.

    1978-01-01

    The kinetics of pack aluminization of unalloyed nickel in packs of varying aluminum activity with various halide activators were studied. Surface compositions of the coatings as functions of time, temperature, and pack composition were obtained in order to establish the boundary conditions for diffusion in the system. The structure of the packs was also examined in order to clarify the mechanism of aluminum transport. The results indicate that the kinetics of pack aluminization are controlled jointly by gas diffusion in the pack and solid diffusion in the coating. Levine and Caves' model for gas diffusion was combined with calculations of rates of diffusion in the solid to formulate a more complete theory for the kinetics of pack aluminization.

  13. Crude oil steam distillation in steam flooding. Final report

    SciTech Connect

    Wu, C.H.; Elder, R.B.

    1980-08-01

    Steam distillation yields of sixteen crude oils from various parts of the United States have been determined at a saturated steam pressure of 200 psig. Study made to investigate the effect of steam pressure (200 to 500 psig) on steam distillation yields indicates that the maximum yields of a crude oil may be obtained at 200 psig. At a steam distillation correlation factor (V/sub w//V/sub oi/) of 15, the determined steam distillation yields range from 12 to 56% of initial oil volume for the sixteen crude oils with gravity ranging from 12 to 40/sup 0/API. Regression analysis of experimental steam distillation yields shows that the boiling temperature (simulated distillation temperature) at 20% simulated distillation yield can predict the steam distillation yields reasonably well: the standard error ranges from 2.8 to 3.5% (in yield) for V/sub w//V/sub oi/ < 5 and from 3.5 to 4.5% for V/sub w//V/sub oi/ > 5. The oil viscosity (cs) at 100/sup 0/F can predict the steam distillation yields with standard error from 3.1 to 4.3%. The API gravity can predict the steam distillation yields with standard error from 4.4 to 5.7%. Characterization factor is an unsatisfactory correlation independent variable for correlation purpose.

  14. Observation of Absence of Mechanical Degradation of High Molecular Weight Polystyrenes During Elution Through a Column in Size Exclusion Chromatography

    Microsoft Academic Search

    Masahide Nakamura; Yurika Ofusa; Sadao Mori

    1996-01-01

    Size exclusion chromatography of several polystyrene (PS) standards of a narrow molecular weight (MW) distribution was performed with an on-line light scattering detector (MALLS) using Shodex SEC column KF 806L packed with PS gel packings. Tetrahydrofuran was used as the mobile phase and the flow rate was 1.0 mL\\/min. Mechanical degradation of the sample PS was not observed even the

  15. Supercage effect for a photochemical reaction in a flow reactor packed with mesoporous silica

    NASA Astrophysics Data System (ADS)

    Okazaki, Masaharu; Konishi, Yoshinari; Toriyama, Kazumi

    2000-09-01

    Mesoporous silica, MCM-41, was packed in a pyrex column and used as a flow reactor for a solution system. The reactant solution, containing xanthone and xanthene, was irradiated with UV light while flowing in the column reactor under a magnetic field. When MCM-41 with a pore diameter of 2.5 nm was employed, a large increase in the `cage reaction' yield was observed in comparison with that for MCM-41, 3.9 nm. About 25% of this nanopore effect was canceled by the magnetic field of 500 mT.

  16. Surface code implementation of block code state distillation

    PubMed Central

    Fowler, Austin G.; Devitt, Simon J.; Jones, Cody

    2013-01-01

    State distillation is the process of taking a number of imperfect copies of a particular quantum state and producing fewer better copies. Until recently, the lowest overhead method of distilling states produced a single improved |A? state given 15 input copies. New block code state distillation methods can produce k improved |A? states given 3k + 8 input copies, potentially significantly reducing the overhead associated with state distillation. We construct an explicit surface code implementation of block code state distillation and quantitatively compare the overhead of this approach to the old. We find that, using the best available techniques, for parameters of practical interest, block code state distillation does not always lead to lower overhead, and, when it does, the overhead reduction is typically less than a factor of three. PMID:23736868

  17. Energy conservation in distillation: a technology applications manual

    SciTech Connect

    Not Available

    1980-05-01

    Distillation is the most widely practiced technique for separating mixtures of chemical species, but it is an energy intensive process. A 10% reduction in distillation energy consumption would effect a significant savings. On a national basis this would be an annual savings of 200 trillion Btu, or the equivalent of 36.5 million barrels of oil per year. Technology to achieve these savings in distillation energy is available and measures are presented to assist process engineers in technical and economic analysis of the energy conservation measures most suitable for particular distillation applications. The manual catalogs all of the energy conservation options applicable to distillation and the options by the investment required; describes in detail the options having a significant potential to reduce distillation energy requirements economically; provides guidelines that will allow the plant engineer to quickly screen each option for his application; and provides short-cut calculation procedures for use in a preliminary economic analysis of promising options.

  18. Distillation of cadmium from uranium–plutonium–cadmium alloy

    Microsoft Academic Search

    Tetsuya Kato; Masatoshi Iizuka; Tadashi Inoue; Takashi Iwai; Yasuo Arai

    2005-01-01

    Uranium–plutonium alloy was prepared by distillation of cadmium from U–Pu–Cd ternary alloy. The initial ternary alloy contained 2.9wt% U and 8.7wt% Pu other than Cd, which were recovered by molten salt electrolysis with liquid Cd cathode. The distillation experiments were conducted in 10g scale of the initial alloy using a small-scale distillation furnace equipped with an evaporator and a condenser

  19. Degradation of TCE, Cr(VI), sulfate, and nitrate mixtures by granular iron in flow-through columns under different microbial conditions

    Microsoft Academic Search

    Sumeet Gandhi; Byung-Taek Oh; Jerald L. Schnoor; Pedro J. J. Alvarez

    2002-01-01

    Flow-through aquifer columns packed with a middle layer of granular iron (Fe0) were used to study the applicability and limitations of bio-enhanced Fe0 barriers for the treatment of contaminant mixtures in groundwater. Concentration profiles along the columns showed extensive degradation of hexavalent chromium Cr(VI), nitrate, sulfate, and trichloroethene (TCE), mainly in the Fe0 layer. One column was bioaugmented with Shewanella

  20. Simultaneous Distillation Extraction of Some Volatile Flavor Components from Pu-erh Tea Samples-Comparison with Steam Distillation-Liquid/Liquid Extraction and Soxhlet Extraction.

    PubMed

    Gu, Xungang; Zhang, Zhengzhu; Wan, Xiaochun; Ning, Jingming; Yao, Chengcheng; Shao, Wanfang

    2009-01-01

    A simutaneous distillation extraction (SDE) combined GC method was constructed for determination of volatile flavor components in Pu-erh tea samples. Dichloromethane and ethyl decylate was employed as organic phase in SDE and internal standard in determination, respectively. Weakly polar DB-5 column was used to separate the volatile flavor components in GC, 10 of the components were quantitatively analyzed, and further confirmed by GC-MS. The recovery covered from 66.4%-109%, and repeatability expressed as RSD was in range of 1.44%-12.6%. SDE was most suitable for the extraction of the anlytes by comparing with steam distillation-liquid/liquid extraction and Soxhlet extraction. Commercially available Pu-erh tea samples, including Pu-erh raw tea and ripe tea, were analyzed by the constructed method. the high-volatile components, such as benzyl alcohol, linalool oxide, and linalool, were greatly rich in Pu-erh raw teas, while the contents of 1,2,3-Trimethoxylbenzene and 1,2,4-Trimethoxylbenzene were much high in Pu-erh ripe teas. PMID:20169174

  1. Simultaneous Distillation Extraction of Some Volatile Flavor Components from Pu-erh Tea Samples—Comparison with Steam Distillation-Liquid/Liquid Extraction and Soxhlet Extraction

    PubMed Central

    Gu, Xungang; Zhang, Zhengzhu; Wan, Xiaochun; Ning, Jingming; Yao, Chengcheng; Shao, Wanfang

    2009-01-01

    A simutaneous distillation extraction (SDE) combined GC method was constructed for determination of volatile flavor components in Pu-erh tea samples. Dichloromethane and ethyl decylate was employed as organic phase in SDE and internal standard in determination, respectively. Weakly polar DB-5 column was used to separate the volatile flavor components in GC, 10 of the components were quantitatively analyzed, and further confirmed by GC-MS. The recovery covered from 66.4%–109%, and repeatability expressed as RSD was in range of 1.44%–12.6%. SDE was most suitable for the extraction of the anlytes by comparing with steam distillation-liquid/liquid extraction and Soxhlet extraction. Commercially available Pu-erh tea samples, including Pu-erh raw tea and ripe tea, were analyzed by the constructed method. the high-volatile components, such as benzyl alcohol, linalool oxide, and linalool, were greatly rich in Pu-erh raw teas, while the contents of 1,2,3-Trimethoxylbenzene and 1,2,4-Trimethoxylbenzene were much high in Pu-erh ripe teas. PMID:20169174

  2. Spectrophotometric flow injection determination of l-ascorbic acid with a packed reactor containing ferric hydroxide

    Microsoft Academic Search

    Airton Vicente Pereira; Orlando Fatibello-Filho

    1998-01-01

    A flow injection system with spectrophotometric detection is proposed for determining l-ascorbic acid in pharmaceutical formulations. In this system a column containing Fe(OH)3 immobilized in polyester resin (packed reactor) is inserted before the detector. Fe(III)-1,10-phenanthroline complex is reduced by l–ascorbic acid to produce Fe(II)-1,10-phenanthroline complex which is monitored at 510 nm. Under the optimum analytical conditions, the linearity of the

  3. Cascade Distillation Subsystem Development: Early Results from the Exploration Life Support Distillation Technology Comparison Test

    NASA Technical Reports Server (NTRS)

    Callahan, Michael R.; Patel, Vipul; Pickering, Karen D.

    2010-01-01

    In 2009, the Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell International, Torrance, California) was assessed in the National Aeronautics and Space Administration (NASA) Exploration Life Support (ELS) distillation comparison test. The purpose of the test was to collect data to support down-selection and development of a primary distillation technology for application in a lunar outpost water recovery system. The CDS portion of the comparison test was conducted between May 6 and August 19, 2009. The system was challenged with two pretreated test solutions, each intended to represent a feasible wastewater generated in a surface habitat. The 30-day equivalent wastewater loading volume for a crew of four was intended to be processed for each wastewater solution. Test Solution 1 consisted of a mixed stream containing human-generated urine and humidity condensate. Test Solution 2 contained the addition of human-generated hygiene wastewater to the solution 1 waste stream components. Approximately 1500 kg of total wastewater was processed through the CDS during testing. Respective recoveries per solution were 93.4 +/- 0.7 and 90.3 +/- 0.5 percent. The average specific energy of the system during testing was calculated to be less than 120 W-hr/kg. The following paper provides detailed information and data on the performance of the CDS as challenged per the ELS distillation comparison test.

  4. Parametric studies in industrial distillation. Part II. Heuristic optimization. [Industrial distillation trains

    Microsoft Academic Search

    D. W. Tedder; D. F. Rudd

    1978-01-01

    The venture cost of operating a single distillation tower is examined as a function of the overhead operating pressure, the feed fractional vaporization, and the vapor to minimum vapor rate ratio. One variable is changed parametrically, while the two remaining are fixed at their optimal values. The percentage increase in cost above the minimum is shown. The relative significance of

  5. Dense packing crystal structures of physical tetrahedra

    E-print Network

    Kallus, Yoav

    2010-01-01

    We present a method for discovering dense packings of general convex hard particles and apply it to study the dense packing behavior of a one-parameter family of particles with tetrahedral symmetry representing a deformation of the ideal mathematical tetrahedron into a less ideal, physical, tetrahedron and all the way to the sphere. Thus, we also connect the two well studied problems of sphere packing and tetrahedron packing on a single axis. Our numerical results uncover a rich optimal-packing behavior, compared to that of other continuous families of particles previously studied. We present four structures as candidates for the optimal packing at different values of the parameter, providing an atlas of crystal structures which might be observed in systems of nano-particles with tetrahedral symmetry.

  6. Kinetics of distillation of essential oil from comminuted ripe juniper ( Juniperus communis L.) berries

    Microsoft Academic Search

    Svetomir Ž. Milojevi?; Tamara D. Stojanovi?; Radosav Pali?; Miodrag L. Lazi?; Vlada B. Veljkovi?

    2008-01-01

    The distillation of essential oil from comminuted ripe berries of Juniperus communis L. (juniper oil) was studied at different hydrodistillation rates. The distillation of juniper consisted of an initial, fast oil distillation followed by a slow oil distillation. Based on this mechanism, the kinetics of juniper oil distillation were described using a two-parameter model of unsteady-state diffusion through the plant

  7. Concentration and Drying of Tea Polyphenols Extracted from Green Tea Using Molecular Distillation and Spray Drying

    Microsoft Academic Search

    Wei-Qiang Tang; Di-Cai Li; Yang-Xiao Lv; Jian-Guo Jiang

    2011-01-01

    The purpose of this study was to develop a method of combining molecular distillation and spray drying to concentrate and dry tea polyphenols extracts. Molecular distillation and spray drying of tea phenols extracts were performed using an orthogonal array design. The order of importance that influenced molecular distillation was distillation temperature > flux > rotational speed. The optimal conditions for concentration by molecular distillation

  8. Close-packing of growing discs

    SciTech Connect

    Bursill, L.A.; Xudong, F. (Melbourne Univ., Parkville (Australia). School of Physics)

    1988-12-01

    Spiral lattices are derived by allowing growing discs to aggregate under a close-packing rule. Both Fibonacci and Lucas numbers of visible spirals arise naturally, dependent only on the choice of growth centre. Both the rate of convergence towards an ideal spiral, and chirality, are determined by the initial placement of the first few discs (initial conditions). Thus the appearance of spiral packings is no more or less mysterious than the appearance of hexagonal packed arrays of equal discs.

  9. Wet packing of crushed rock fine aggregate

    Microsoft Academic Search

    W. W. S. Fung; A. K. H. Kwan; H. H. C. Wong

    2009-01-01

    It is well known that the performance of concrete is dependent on the packing density of the aggregate. All existing methods\\u000a of measuring the packing density of aggregate are carried out under dry condition. However, these dry packing methods are\\u000a sensitive to the amount of compaction applied and do not account for the effect of water in the concrete mix.

  10. Circle Packing for Origami Design Is Hard

    E-print Network

    Demaine, Erik D; Lang, Robert J

    2010-01-01

    We show that deciding whether a given set of circles can be packed into a rectangle, an equilateral triangle, or a unit square are NP-hard problems, settling the complexity of these natural packing problems. On the positive side, we show that any set of circles of total area 1 can be packed into a square of size 8/pi=2.546... These results are motivated by problems arising in the context of origami design.

  11. Precise discrimination among homologous sequences by DNA probe column chromatography.

    PubMed

    Tsurui, H; Kishimoto, T; Sanokawa, R; Shirai, T

    1991-01-01

    Synthesized oligo probes were immobilized to a HPLC gel in high concentrations (30-40 O.D. per gram dry gel), packed in a column (2mm x 10cm) and incorporated into a conventional HPLC system. The system was applied to the discrimination among homologous sequences. Two probes different in sequence and length (16mer and 24mer) were investigated under isothermal and isocratic conditions. For each probe, 4 oligos of similar sequences, one perfectly matched to the probe and others containing one mismatch in the center of the chain, were synthesized. The chromatogram obtained as the results of high performance liquid affinity chromatography (HPLAC) considerably varied with the column temperature and the type of mismatches. The dependency of the deformation of elution profile upon mismatch seemed to reflect the stability of the hybrid composed of samples and immobilized probe. PMID:1842087

  12. Compact electron beam focusing column

    SciTech Connect

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

    2001-07-13

    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 2-D 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.

  13. Diffusion in jammed particle packs

    NASA Astrophysics Data System (ADS)

    Bolintineanu, Dan S.; Silbert, Leonardo E.; Grest, Gary S.; Lechman, Jeremy B.

    2015-03-01

    Diffusive transport in jammed particle packs is of interest for a number of applications, as well as being a potential indicator of structural properties near the jamming point. To this end, we report stochastic simulations of equilibrium diffusion through monodisperse sphere packs near the jamming point in the limit of a perfectly insulating surrounding medium. The time dependence of various diffusion properties is resolved over several orders of magnitude. Two time regimes of expected Fickian diffusion are observed, separated by an intermediate regime of anomalous diffusion. This intermediate regime grows as the particle volume fraction approaches the critical jamming transition. The diffusion behavior is fully controlled by the extent of the contacts between neighboring particles, which in turn depend on proximity to the jamming point. In particular, the mean first passage time associated with the escape of random walkers between neighboring particles is shown to control both the time to recover Fickian diffusion and the long time diffusivity. Scaling laws are established that relate these quantities to the difference between the actual and critical jamming volume fractions. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's NNSA under Contract DE- AC04-94AL85000.

  14. Random packing of spheres in Menger sponge

    NASA Astrophysics Data System (ADS)

    Cie?la, Micha?; Barbasz, Jakub

    2013-06-01

    Random packing of spheres inside fractal collectors of dimension 2 < d < 3 is studied numerically using Random Sequential Adsorption (RSA) algorithm. The paper focuses mainly on the measurement of random packing saturation limit. Additionally, scaling properties of density autocorrelations in the obtained packing are analyzed. The RSA kinetics coefficients are also measured. Obtained results allow to test phenomenological relation between random packing saturation density and collector dimension. Additionally, performed simulations together with previously obtained results confirm that, in general, the known dimensional relations are obeyed by systems having non-integer dimension, at least for d < 3.

  15. Dense crystalline dimer packings of regular tetrahedra

    E-print Network

    Chen, Elizabeth R; Glotzer, Sharon C

    2010-01-01

    We have discovered the densest known packing of regular tetrahedra with a density phi = 4000/4671 = 0.856347.... Like the recently discovered packings of Kallus et al. [arXiv:0910.5226] and Torquato-Jiao [arXiv:0912.4210], our packing is crystalline with a unit cell of four tetrahedra forming two triangular bipyramids (dimer clusters) and is cluster transitive. The densest packing is a special case of an analytical three-parameter family of dimer packings we have constructed. The slightly lower packing densities of phi = 100/117 = 0.854700... (Kallus et al.) and phi = 12250/14319 = 0.855506... (Torquato-Jiao), obtained via analytical one-parameter and two-parameter families of dimer packings, respectively, are shown to be suboptimal cases of our more general formalism. Numerical compressions starting from random configurations confirm that the reported packing is optimal at least for small systems with up to 16 tetrahedra. For all systems with four or more tetrahedra, we obtain packings with densities higher ...

  16. Establishing column batch repeatability according to Quality by Design (QbD) principles using modeling software.

    PubMed

    Rácz, Norbert; Kormány, Róbert; Fekete, Jen?; Molnár, Imre

    2015-04-10

    Column technology needs further improvement even today. To get information of batch-to-batch repeatability, intelligent modeling software was applied. Twelve columns from the same production process, but from different batches were compared in this work. In this paper, the retention parameters of these columns with real life sample solutes were studied. The following parameters were selected for measurements: gradient time, temperature and pH. Based on calculated results, batch-to-batch repeatability of BEH columns was evaluated. Two parallel measurements on two columns from the same batch were performed to obtain information about the quality of packing. Calculating the average of individual working points at the highest critical resolution (R(s,crit)) it was found that the robustness, calculated with a newly released robustness module, had a success rate >98% among the predicted 3(6) = 729 experiments for all 12 columns. With the help of retention modeling all substances could be separated independently from the batch and/or packing, using the same conditions, having high robustness of the experiments. PMID:25703234

  17. Comparative evaluation of the swelling and degrees of cross-linking in three organic gel packings for SEC through some geometric parameters

    Microsoft Academic Search

    Rosa Garc??a; Clara M Gómez; Armando Codoñer; Concepción Abad; Agust??n Campos

    2003-01-01

    The size exclusion chromatographic (SEC) behavior of five solvent\\/polymer systems in three organic column packings based on polystyrene\\/divinylbenzene (PS\\/DVB) copolymer, TSK-Gel HHR, ?-styragel and TSK-Gel HXL, has been compared. All the packings offer similar characteristics (pore size, particle size and efficiency) but some differences have been found when eluting the same systems. The different elution behavior observed in both polymeric

  18. Grain Packing Resistance to Particle Mobility

    NASA Astrophysics Data System (ADS)

    Buxton, T. H.; Yager, E.; Buffington, J. M.; Hassan, M. A.; Fremier, A. K.

    2014-12-01

    We report model results for quantifying grain packing resistance to particle motion. Packing resistance was modeled as the difference between the total resistance acting on individual grains (measured with a load cell) and the resistance that occurs when grains interact with the geometry of their resting pocket (measured with a tilt board). Monte Carlo simulations were conducted to develop distributions of packing resistance from observed distributions of total and pocket angle resistance because paired measurements were not available. Results show that packing was the dominant form of resistance to grain motion, exceeding pocket angle resistance by up to 88%. Expressed as coefficients of friction, packing resistance was close to 18 times higher for smaller grains because such particles tend to be more embedded, increasing the extent of packing by surrounding grains. We developed a predictive equation from these data, expressing packing resistance as a function of grain size, embeddedness, and the standard deviation of grain sizes on the bed surface (sorting), which collectively control the frictional surface area of the grain. Including observed values of packing resistance in calculations of critical bed shear stress increased thresholds of grain motion by 8 to 46% (21% on average) over that calculated with pocket angle resistance. This has significant implications for bed load transport predictions, which are typically nonlinear functions of the difference between applied and critical shear stresses; as such, small differences in critical shear stress can cause large prediction errors. Given the importance of packing resistance, future studies are warranted to better understand the physical and biological controls on packing, as well as the mechanics of packing resistance.

  19. Soybean meal, distillers grains replace fishmeal in experimental shrimp diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to evaluate inclusion of distiller’s dried grains with solubles (DDGS) as partial replacement of commercial, solvent-extracted soybean meal (SBM) in fish meal-free diets for Pacific white shrimp, Litopenaeus vannamei. Aquaria connected to a recirculating biofiltratio...

  20. Azeotropic Distillation as a Technique for Emulsion Size Reduction

    E-print Network

    Petta, Jason

    : A solvent with HA Boiling point with water Heptane or Hexane Low vapor pressure viscosifying oil Distillation setup/ process -Found the Heterogeneous Azeotropic Distillation Boiling points for Water% Solvent Initial Size(µm) Size after one hour(µm) Boiling point Range (°C) 25% PB320 Span 80 75% hex. 28

  1. Homogeneous azeotropic pressure swing distillation: Continuous and batch process

    Microsoft Academic Search

    Jens-Uwe Repke; Andreas Klein

    2005-01-01

    The separation of a binary homogeneous azeotropic mixture using pressure swing distillation will be analysed on the example of acetonitrile\\/water. Two different processes are considered: the continuous heat- and mass-integrated process and the inverted batch process. For both processes a model is developed and experimental data are given. In the paper the potential of the pressure swing distillation for the

  2. Estimation of convective mass transfer in solar distillation systems

    Microsoft Academic Search

    Sanjay Kumar; G. N. Tiwari

    1996-01-01

    In this article a thermal model has been developed to determine the convective mass transfer for different Grashof Number range in solar distillatiOn process. The model is based on simple regression analysis. Based on the experimental data obtained from the rigorous outdoor experimentation on passive and active distillation systems for summer climatic conditions, the values of C and n have

  3. Catalytic oxidation of mercaptan in sour petroleum distillate

    SciTech Connect

    Frame, R.R.

    1981-04-07

    A process for treating a mercaptan-containing sour petroleum distillate is disclosed. The process comprises contacting said distillate with a supported mercaptan oxidation catalyst at oxidation conditions, said catalyst comprising a metal chelate and a quaternary ammonium hydroxide disposed on an adsorbent support.

  4. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...containing aldehydes may be received on wine premises for use in the fermentation of wine and then returned to the distilled spirits plant...Distillates produced from one kind of fruit may not be used in the fermentation of wine made from a different kind of fruit....

  5. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...containing aldehydes may be received on wine premises for use in the fermentation of wine and then returned to the distilled spirits plant...Distillates produced from one kind of fruit may not be used in the fermentation of wine made from a different kind of fruit....

  6. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...containing aldehydes may be received on wine premises for use in the fermentation of wine and then returned to the distilled spirits plant...Distillates produced from one kind of fruit may not be used in the fermentation of wine made from a different kind of fruit....

  7. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...containing aldehydes may be received on wine premises for use in the fermentation of wine and then returned to the distilled spirits plant...Distillates produced from one kind of fruit may not be used in the fermentation of wine made from a different kind of fruit....

  8. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...containing aldehydes may be received on wine premises for use in the fermentation of wine and then returned to the distilled spirits plant...Distillates produced from one kind of fruit may not be used in the fermentation of wine made from a different kind of fruit....

  9. Potential Bleaching Techniques for use in Distillers Grains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ethanol industry is booming. And extensive research is currently being pursued to develop alternative uses for distillers dried grains (DDG) and distillers dried grains with solubles (DDGS), coproducts of the ethanol production process. Currently, DDG and DDGS are used exclusively as livestock f...

  10. Vegetable Oil Deodorizer Distillate: Characterization, Utilization and Analysis

    Microsoft Academic Search

    Setiyo Gunawan

    2009-01-01

    Depending on the sources, deodorizer distillates usually have significantly different characteristics, uses, and value. Soybean oil deodorizer distillate has been suggested as an alternative to marine animals as natural source of squalene and as a good raw material for the production of fatty acid steryl esters, tocopherols, free phytosterols and fatty acids. The aim of this review paper is to

  11. HPLC analysis of synthetic polymers on short monolithic columns.

    PubMed

    Maksimova, Elena; Vlakh, Evgenia; Sinitsyna, Ekaterina; Tennikova, Tatiana

    2013-12-01

    Ultrashort monolithic columns (disks) were thoroughly studied as efficient stationary phases for precipitation-dissolution chromatography of synthetic polymers. Gradient elution mode was applied in all chromatographic runs. The mixtures of different flexible chain homopolymers, such as polystyrenes, poly(methyl methacrylates), and poly(tert-butylmethacrylates) were separated according to their molecular weights on both commercial poly(styrene-co-divinylbenzene) disks (12 id × 3 mm and 5 × 5 mm) and lab-made monolithic columns (4.6 id × 50 mm) filled with supports of different hydrophobicity. The experimental conditions were optimized to reach fast and highly efficient separation. It was observed that, similar to the separation of monoliths of other classes of (macro)molecules (proteins, DNA, oligonucleotides), the length of column did not affect the peak resolution. A comparison of the retention properties of the poly(styrene-co-divinylbenzene) disk-shaped monoliths with those based on poly(lauryl methacrylate-co-ethylene dimethacrylate), poly(butyl methacrylate-co-ethylene dimethacrylate), and poly(glycidyl methacrylate-co-ethylene dimethacrylate) supports demonstrated the obvious effect of surface chemistry on the resolution factor. Additionally, the results of the discussed chromatographic mode on the fast determination of the molecular weights of homopolymers used in this study were compared to those established by SEC on columns packed with sorbent beads of a similar nature to the monoliths. PMID:24106069

  12. Towards the Classical Communication Complexity of Entanglement Distillation Protocols with Incomplete Information

    E-print Network

    Yang, Ke

    Towards the Classical Communication Complexity of Entanglement Distillation Protocols. Entanglement distil­ lation extracts nearly­perfect entanglement from imperfect entangled state. The classical­ nication complexity of entanglement distillation protocols for this model. Our result also suggests

  13. Towards the Classical Communication Complexity of Entanglement Distillation Protocols with Incomplete Information

    E-print Network

    Yang, Ke

    Towards the Classical Communication Complexity of Entanglement Distillation Protocols. Entanglement distil- lation extracts nearly-perfect entanglement from imperfect entangled state. The classical- nication complexity of entanglement distillation protocols for this model. Our result also suggests

  14. 77 FR 38758 - Proposed Amendment to the Standards of Identity for Distilled Spirits; Comment Period Extension

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-29

    ...Proposed Amendment to the Standards of Identity for Distilled Spirits; Comment Period...Proposed Amendment to the Standards of Identity for Distilled Spirits, for an additional...TTB proposes to amend the standards of identity regulations for distilled spirits...

  15. 27 CFR 28.281 - Certificate of use for distilled spirits and wines.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Certificate of use for distilled spirits and wines. 28.281 Section 28.281 Alcohol...Certificate of use for distilled spirits and wines. When all of the distilled spirits or wines represented by a single...

  16. 27 CFR 28.28 - Withdrawal of wine and distilled spirits from customs bonded warehouses.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 2010-04-01 false Withdrawal of wine and distilled spirits from customs bonded...Bonded Warehouses § 28.28 Withdrawal of wine and distilled spirits from customs bonded warehouses. Wine and bottled distilled spirits...

  17. 27 CFR 27.61 - Containers of distilled spirits to bear closures.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 2011-04-01 false Containers of distilled spirits to bear closures. 27.61 Section 27.61 Alcohol, Tobacco Products...Distilled Spirits § 27.61 Containers of distilled spirits to bear closures. No person shall transport, buy,...

  18. 27 CFR 27.61 - Containers of distilled spirits to bear closures.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 2010-04-01 false Containers of distilled spirits to bear closures. 27.61 Section 27.61 Alcohol, Tobacco Products...Distilled Spirits § 27.61 Containers of distilled spirits to bear closures. No person shall transport, buy,...

  19. 27 CFR 24.247 - Materials authorized for the treatment of distilling material.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...potassium and sodium salts of benzoic acid To prevent fermentation of the sugar in wine being accumulated as distilling material...favorable yeast development in distilling material; to prevent fermentation of the sugar in wine being accumulated as distilling...

  20. 27 CFR 24.247 - Materials authorized for the treatment of distilling material.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...potassium and sodium salts of benzoic acid To prevent fermentation of the sugar in wine being accumulated as distilling material...favorable yeast development in distilling material; to prevent fermentation of the sugar in wine being accumulated as distilling...

  1. 27 CFR 24.247 - Materials authorized for the treatment of distilling material.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...potassium and sodium salts of benzoic acid To prevent fermentation of the sugar in wine being accumulated as distilling material...favorable yeast development in distilling material; to prevent fermentation of the sugar in wine being accumulated as distilling...

  2. 27 CFR 24.247 - Materials authorized for the treatment of distilling material.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...potassium and sodium salts of benzoic acid To prevent fermentation of the sugar in wine being accumulated as distilling material...favorable yeast development in distilling material; to prevent fermentation of the sugar in wine being accumulated as distilling...

  3. 27 CFR 24.247 - Materials authorized for the treatment of distilling material.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...potassium and sodium salts of benzoic acid To prevent fermentation of the sugar in wine being accumulated as distilling material...favorable yeast development in distilling material; to prevent fermentation of the sugar in wine being accumulated as distilling...

  4. 27 CFR 27.75 - Samples of distilled spirits, wine, and beer for quality control purposes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Samples of distilled spirits, wine, and beer for quality control purposes. 27.75...IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER General Requirements Exemptions ...Samples of distilled spirits, wine, and beer for quality control purposes....

  5. 27 CFR 27.75 - Samples of distilled spirits, wine, and beer for quality control purposes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Samples of distilled spirits, wine, and beer for quality control purposes. 27.75...IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER General Requirements Exemptions ...Samples of distilled spirits, wine, and beer for quality control purposes....

  6. 27 CFR 27.1 - Imported distilled spirits, wines, and beer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Imported distilled spirits, wines, and beer. 27.1 Section 27.1 Alcohol...IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER Scope of Regulations § 27.1 Imported distilled spirits, wines, and beer. This part, “Importation of...

  7. 27 CFR 27.1 - Imported distilled spirits, wines, and beer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Imported distilled spirits, wines, and beer. 27.1 Section 27.1 Alcohol...IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER Scope of Regulations § 27.1 Imported distilled spirits, wines, and beer. This part, “Importation of...

  8. Selected Topics in Column Generation

    Microsoft Academic Search

    Marco E. Lübbecke; Jacques Desrosiers

    2005-01-01

    Abstract Dantzig-Wolfe decomposition and column generation, devised for linear programs, is a success story in large scale integer programming. We outline and relate the approaches, and survey mainly recent contributions, not found in textbooks, yet. We emphasize on the growing understanding of the dual point of view, which brought considerable progress to the column generation theory and practice. It stimulated

  9. Modeling of transient flow through a viscoelastic preparative chromatography packing.

    PubMed

    Hekmat, Dariusch; Kuhn, Michael; Meinhardt, Verena; Weuster-Botz, Dirk

    2013-01-01

    The common method for purification of macromolecular bioproducts is preparative packed-bed chromatography using polymer-based, compressible, viscoelastic resins. Because of a downstream processing bottleneck, the chromatography equipment is often operated at its hydrodynamic limit. In this case, the resins may exhibit a complex behavior which results in compression-relaxation hystereses. Up to now, no modeling approach of transient flow through a chromatography packing has been made considering the viscoelasticity of the resins. The aim of the present work was to develop a novel model and compare model calculations with experimental data of two agarose-based resins. Fluid flow and bed permeability were modeled by Darcy's law and the Kozeny-Carman equation, respectively. Fluid flow was coupled to solid matrix stress via an axial force balance and a continuity equation of a deformable packing. Viscoelasticity was considered according to a Kelvin-Voigt material. The coupled equations were solved with a finite difference scheme using a deformable mesh. The model boundary conditions were preset transient pressure drop functions which resemble simulated load/elution/equilibration cycles. Calculations using a homogeneous model (assuming constant variables along the column height) gave a fair agreement with experimental data with regard to predicted flow rate, bed height, and compression-relaxation hysteresis for symmetric as well as asymmetric pressure drop functions. Calculations using an inhomogeneous model gave profiles of the bed porosity as a function of the bed height. In addition, the influence of medium wall support and intraparticle porosity was illustrated. The inhomogeneous model provides insights that so far are not easily experimentally accessible. PMID:23798499

  10. Voronoia: analyzing packing in protein structures

    Microsoft Academic Search

    Kristian Rother; Peter Werner Hildebrand; Andrean Goede; Bjoern Gruening; Robert Preissner

    2009-01-01

    The packing of protein atoms is an indicator for their stability and functionality, and applied in determin- ing thermostability, in protein design, ligand binding and to identify flexible regions in proteins. Here, we present Voronoia, a database of atomic-scale pack- ing data for protein 3D structures. It is based on an improved Voronoi Cell algorithm using hyperboloid interfaces to construct

  11. Hamiltonian mappings and circle packing phase spaces

    E-print Network

    A. J. Scott; C. A. Holmes; G. J. Milburn

    2001-02-21

    We introduce three area preserving maps with phase space structures which resemble circle packings. Each mapping is derived from a kicked Hamiltonian system with one of three different phase space geometries (planar, hyperbolic or spherical) and exhibits an infinite number of coexisting stable periodic orbits which appear to `pack' the phase space with circular resonances.

  12. Reliability Analysis of Aircraft Air Conditioning Packs

    Microsoft Academic Search

    A. Z. Al-Garni; M. Tozan; A. Kassem; S. Farooq

    Air conditioning packs of aircraft are subject to a number of failures like other aircraft components. However, the number and results of unexpected failures in the Kingdom are expected to be more severe than the corresponding failures in many other countries due to climatic conditions. This paper examines the time-to failure distribution of Boeing 737 air conditioning packs by using

  13. Pack Density Limitations of Hybrid Parachutes

    NASA Technical Reports Server (NTRS)

    Zwicker, Matthew L.; Sinclair, Robert J.

    2013-01-01

    The development and testing of the Orion crew capsule parachute system has provided a unique opportunity to study dense parachute packing techniques and limits, in order to establish a new baseline for future programs. The density of parachute packs has a significant influence on vibration loads, retention system stresses, and parachute mortar performance. Material compositions and pack densities of existing designs for space capsule recovery were compared, using the pack density of the Apollo main parachutes as the current baseline. The composition of parachutes has changed since Apollo, incorporating new materials such as Kevlar , Vectran , Teflon and Spectra . These materials have different specific densities than Nylon, so the densities of hybrid parachute packs cannot be directly compared to Nylon parachutes for determination of feasibility or volume allocation. Six parachute packs were evaluated in terms of weighted average solid density in order to achieve a non-dimensional comparison of packing density. Means of mitigating damage due to packing pressure and mortar firing were examined in light of the Capsule Parachute Assembly System (CPAS) and Apollo experience. Parachute design improvements including incorporation of modern materials and manufacturing processes serves to make CPAS the new knowledge base on which future spacecraft parachute systems will be built.

  14. Is incest common in gray wolf packs?

    Microsoft Academic Search

    Deborah Smith; Thomas Meier; Eli Geffen; L. David Mech; John W. Burch; Layne G. Adams; Robert K. Wayne

    1997-01-01

    Wolf packs generally consist of a breeding pair and their maturing of&pring that help provision and protect pack young. Because the reproductive tenure in wolves is often short, reproductively mature offspring might replace their parents, resulting in sibling or parent-offspr ing matings. To determine the extent of incestuous pairings, we measured relatedness based on variability in 20 microsatellit e loci

  15. Modelling of cooling tower splash pack

    Microsoft Academic Search

    A. A. Dreyer; P. J. Erens

    1996-01-01

    A mathematical model and a computer simulation program have been developed for the modelling of counterflow cooling tower splash pack thermal performance. The one-dimensional model uses basic aerodynamic, hydrodynamic and heat\\/mass transfer information to predict the performance of the packing material without depending on cooling tower test data. The predicted transfer characteristics and pressure drop data obtained with the simulation

  16. Pack rats (Neotoma spp.): Keystone ecological engineers?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential role of two species of pack rats (Neotoma albigula and Neotoma micropus) as keystone ecological engineers was examined by estimating the species diversity of invertebrates living in the nest middens, and nitrogen mineralization rates in soils associated with the middens. Although pack-...

  17. SHAPE DETECTION BY PACKING CONTOURS A DISSERTATION

    E-print Network

    Shi, Jianbo

    SHAPE DETECTION BY PACKING CONTOURS Qihui Zhu A DISSERTATION in Computer and Information Science Zhao, Peng Li, Liang Huang, Stephen Tse, John Blitzer, Jinsong Tan, Mengmeng Liu, Zhuowei Bao, Jianzhou SHAPE DETECTION BY PACKING CONTOURS Qihui Zhu Jianbo Shi Humans have an amazing ability to localize

  18. Data Envelopment Analysis Course Welcome Pack

    E-print Network

    Hall, Julian

    1 NATCOR Data Envelopment Analysis Course 28th June 2014 Welcome Pack This pack contains. ABSTRACT Data Envelopment Analysis (DEA) is a rapidly growing area of operational research that deals: Cooper, W. W., L. M. Seiford, K. Tone. 2006. Introduction to Data Envelopment Analysis and Its Uses

  19. Cluster and constraint analysis in tetrahedron packings.

    PubMed

    Jin, Weiwei; Lu, Peng; Liu, Lufeng; Li, Shuixiang

    2015-04-01

    The disordered packings of tetrahedra often show no obvious macroscopic orientational or positional order for a wide range of packing densities, and it has been found that the local order in particle clusters is the main order form of tetrahedron packings. Therefore, a cluster analysis is carried out to investigate the local structures and properties of tetrahedron packings in this work. We obtain a cluster distribution of differently sized clusters, and peaks are observed at two special clusters, i.e., dimer and wagon wheel. We then calculate the amounts of dimers and wagon wheels, which are observed to have linear or approximate linear correlations with packing density. Following our previous work, the amount of particles participating in dimers is used as an order metric to evaluate the order degree of the hierarchical packing structure of tetrahedra, and an order map is consequently depicted. Furthermore, a constraint analysis is performed to determine the isostatic or hyperstatic region in the order map. We employ a Monte Carlo algorithm to test jamming and then suggest a new maximally random jammed packing of hard tetrahedra from the order map with a packing density of 0.6337. PMID:25974480

  20. Particle packing using computational and experimental simulation

    Microsoft Academic Search

    Mohamad Waseem Dekelbab

    2002-01-01

    The prediction of the packing density for a granular mixture is a problem of relevance to cement concrete. It is also relevant to many other industrial sectors (e.g., compacting pills for pharmaceutical industry, packing and storing seeds for agriculture, deposition of natural sand, etc.) Many composite materials like concrete are made of granular material embedded in a binding matrix. The

  1. Cluster and constraint analysis in tetrahedron packings

    NASA Astrophysics Data System (ADS)

    Jin, Weiwei; Lu, Peng; Liu, Lufeng; Li, Shuixiang

    2015-04-01

    The disordered packings of tetrahedra often show no obvious macroscopic orientational or positional order for a wide range of packing densities, and it has been found that the local order in particle clusters is the main order form of tetrahedron packings. Therefore, a cluster analysis is carried out to investigate the local structures and properties of tetrahedron packings in this work. We obtain a cluster distribution of differently sized clusters, and peaks are observed at two special clusters, i.e., dimer and wagon wheel. We then calculate the amounts of dimers and wagon wheels, which are observed to have linear or approximate linear correlations with packing density. Following our previous work, the amount of particles participating in dimers is used as an order metric to evaluate the order degree of the hierarchical packing structure of tetrahedra, and an order map is consequently depicted. Furthermore, a constraint analysis is performed to determine the isostatic or hyperstatic region in the order map. We employ a Monte Carlo algorithm to test jamming and then suggest a new maximally random jammed packing of hard tetrahedra from the order map with a packing density of 0.6337.

  2. The Maximum Resource Bin Packing Problem

    Microsoft Academic Search

    Joan Boyar; Leah Epstein; Lene M. Favrholdt; Jens S. Kohrt; Kim S. Larsen; Morten Monrad Pedersen; Sanne Wøhlk

    2005-01-01

    Usually, for bin packing problems, we try to minimize the number of bins used or in the case of the dual bin packing problem, maximize the number or total size of accepted items. This paper presents results for the opposite problems, where we would like to maximize the number of bins used or minimize the number or total size of

  3. The maximum resource bin packing problem

    Microsoft Academic Search

    Joan Boyar; Leah Epstein; Lene M. Favrholdt; Jens S. Kohrt; Kim S. Larsen; Morten Monrad Pedersen; Sanne Wøhlk

    2006-01-01

    Abstract. Usually, for bin packing problems, we try to minimize the number of bins used or in the case of the dual bin packing problem, maximize the number or total size of accepted items. This paper presents results for the opposite problems, where we would like to maximize the number of bins used or minimize the number,or total size of

  4. Packing of elastic wires in flexible shells

    E-print Network

    Roman Vetter; Falk K. Wittel; Hans J. Herrmann

    2015-04-03

    The packing problem of long thin filaments that are injected into confined spaces is of fundamental interest for physicists, biologists and materials engineers alike. How linear threads pack and coil is well known only for the ideal case of rigid containers, however. Here, we force long elastic rods into flexible spatial confinement borne by an elastic shell to examine under which conditions recently acquired knowledge on wire packing in rigid spheres breaks down. We find that unlike in rigid cavities, friction plays a key role by giving rise to the emergence of two distinct packing patterns. At low friction, the wire densely coils into an ordered toroidal bundle with semi-ellipsoidal cross section, while at high friction, it packs into a highly disordered, self-similar structure. These two morphologies are shown to be separated by a continuous phase transition.

  5. Packing of elastic wires in flexible shells

    E-print Network

    Vetter, Roman; Herrmann, Hans J

    2015-01-01

    The packing problem of long thin filaments that are injected into confined spaces is of fundamental interest for physicists, biologists and materials engineers alike. How linear threads pack and coil is well known only for the ideal case of rigid containers, however. Here, we force long elastic rods into flexible spatial confinement borne by an elastic shell to examine under which conditions recently acquired knowledge on wire packing in rigid spheres breaks down. We find that unlike in rigid cavities, friction plays a key role by giving rise to the emergence of two distinct packing patterns. At low friction, the wire densely coils into an ordered toroidal bundle with semi-ellipsoidal cross section, while at high friction, it packs into a highly disordered, self-similar structure. These two morphologies are shown to be separated by a continuous phase transition.

  6. Coalescence preference in densely packed microbubbles

    PubMed Central

    Kim, Yeseul; Lim, Su Jin; Gim, Bopil; Weon, Byung Mook

    2015-01-01

    A bubble merged from two parent bubbles with different size tends to be placed closer to the larger parent. This phenomenon is known as the coalescence preference. Here we demonstrate that the coalescence preference can be blocked inside a densely packed cluster of bubbles. We utilized high-speed high-resolution X-ray microscopy to clearly visualize individual coalescence events inside densely packed microbubbles with a local packing fraction of ~40%. The surface energy release theory predicts an exponent of 5 in a relation between the relative coalescence position and the parent size ratio, whereas our observation for coalescence in densely packed microbubbles shows a different exponent of 2. We believe that this result would be important to understand the reality of coalescence dynamics in a variety of packing situations of soft matter. PMID:25583640

  7. Particle size distribution and column efficiency. An ongoing debate revived with 1.9?m Titan-C18 particles.

    PubMed

    Gritti, Fabrice; Bell, David S; Guiochon, Georges

    2014-08-15

    The mass transfer mechanism in four prototype columns (2.1 and 3.0×50mm, 2.1 and 3.0×100mm) packed with 1.9?m fully porous Titan-C18 particles was investigated by using two previously reported home-made protocols. The first one was used to measure the eddy dispersion HETP of these new columns, the second one to estimate their intrinsic (corrected for HPLC system contribution) HETPs. Titan particles are fully porous particles with a narrow particle size distribution (RSD of 9.2%). The mean Sauter diameter (dSauter=2.04?m) was determined from Coulter counter measurements on the raw silica material (before C18 derivatization) and in the absence of a dispersant agent (Triton X-100) in a 2% NaCl electrolyte solution. The results show that these RPLC Titan columns have intrinsic minimum reduced HETPs ranging from 1.7 to 1.9 and generate up to 290,000 plates per meter. The 3.0mm i.d. columns are more efficient than the 2.1mm i.d. ones and short columns are preferred to minimize efficiency losses due to frictional heating at high speeds. This work also revealed that (1) the lowest h values of the Titan columns are observed at low reduced velocities (?opt=5); (2) this is due to the unusually small diffusivity of analytes across the porous Titan-C18 particles; and (3) the Titan columns are not packed more uniformly than conventional columns packed with fully porous particles. Earlier and recent findings showing that the PSD has no direct physical impact on eddy dispersion and column efficiency are confirmed by these results. PMID:25001333

  8. Optimization and scale-up of oligonucleotide synthesis in packed bed reactors using computational fluid dynamics modeling.

    PubMed

    Wolfrum, Christian; Josten, Andre; Götz, Peter

    2014-01-01

    A computational fluid dynamics (CFD) model for the analysis of oligonucleotide synthesis in packed bed reactors was developed and used to optimize the scale up of the process. The model includes reaction kinetics data obtained under well defined conditions comparable to the situation in the packed bed. The model was validated in terms of flow conditions and reaction kinetics by comparison with experimental data. Experimental validation and the following model parameter studies by simulation were performed on the basis of a column with 0.3 g oligonucleotide capacity. The scale-up studies based on CFD modelling were calculated on a 440 g scale (oligonucleotide capacity). PMID:25105730

  9. On the snap-back behavior of a self-deploying antiprismatic column during packing

    E-print Network

    Engineering, Thököly út 74, H-1146 Budapest, Hungary b Institute of Mathematics, Faculty of Natural Sciences, Budapest University of Technology and Economics, 3-9, Muegyetem rkp., H-1111 Budapest, Hungary c Structural Engineering Department, Faculty of Civil Engineering, Budapest University of Technology and Economics, 3

  10. CONDITIONING COAL GAS WITH REFRIGERATED METHANOL IN A SYSTEM OF PACKED COLUMNS

    EPA Science Inventory

    The paper discusses potential difficulties in the operation of acid gas removal systems gases produced from coal, based on experience with pilot-scale unit operation. The pilot plant has been used to condition gases produced from subbituminous coal, devolatilized char, peat, and ...

  11. Interaction mechanisms on octadecyl packed columns in subcritical fluid chromatography with CO2-modifier mobile phases.

    PubMed

    Lesellier, E; Gurdale, K; Tchapla, A

    2002-11-01

    An experimental design was carried out for describing the interaction mechanisms between solutes and octadecyl bonded silicas in subcritical fluid chromatography (SubFC), with CO2-methanol and CO2-acetonitrile mobile phases. The effects of modifier amount, temperature and outlet pressure were studied. The homologous series of alkylbenzenes was mainly used as probe, and results were in part assessed with other series. Curves between the methylene selectivity (alphaCH2) and the alkyl chain carbon number (Cn) were plotted, because changes of slope or discontinuity in these curves are yielded by interaction mechanism modifications. Moreover, the linearity of the Van 't Hoff curves with CO2-acetonitrile mobile phases has enabled one to calculate the transfer enthalpy (deltaH) for each homologue. The curves log k = f(-deltaH) allow a discrimination of the retention behaviors between the short and the long homologues for CO2-acetonitrile mobile phases. Depending on the analytical conditions, different oriented partition mechanisms occur for the long homologues, when the short ones seem to be fully embedded into the grafted chains near the silica surface. With methanol-CO2 mobile phases the discrimination between the homologues disappears and the methylene selectivity curves correspond to a bulk partition mechanism. The differences in the interaction mechanisms following the modifier nature are related to the adsorption the mobile phase onto the stationary phase, because the amount of adsorbed mobile phase modifies the bonded chain mobility. With methanol, an important adsorption of the mobile phase occurs, when this adsorption is reduced with acetonitrile. In this latter case, an anisotropy in the stationary phase mobility can explain the observed difference in the interaction mechanisms of homologues. Finally, effects of stationary phase chain length (from C18 to C22) and bonding density (from 2.5 to 3.4 micromol m(-2)) were also reported. PMID:12456087

  12. System dynamics and controller development for denitrification using a packed column bioreactor

    E-print Network

    Boyd, Michael Edward

    1996-01-01

    the system to be used without constant computerized monitoring. LITERATURE REVIEW In areas of intense agriculture, the levels of nitrate in ground and surface waters conunue to rise (Solt 1989). In Texas, 72 percent of all groundwater used is used...

  13. Adsorption Properties of Montmorillonite and Synthetic Saponite as Packing Materials in Liquid-Column Chromatography

    Microsoft Academic Search

    Yuji Nakamura; AKIHIKO YAMAGISHI; TOSCHITAKE IWAMOTO; MAKOTO KOGA

    1988-01-01

    The adsorption of tris(1,10-phenanthroline)-ruthenium(II) (Ru(phen)32+ ) by two kinds of col- loidaIly dispersed clays, sodium montmorillonite and synthetic saponite, was studied by spectrophoto- metric and electron-optical methods. Montmorillonite adsorbed this complex stronger than saponite. The electronic spectrum measurements suggested that the electronic states of the complex were more perturbed on adsorption by montmorillonite than by saponite. High-performance liquid chromatography was

  14. Purification of Soybean Phosphatidylcholine Using D113-III Ion Exchange Macroporous Resin Packed Column Chromatography

    Microsoft Academic Search

    Yuanfa Liu; Liang Shan; Xingguo Wang

    2009-01-01

    Ten ion-exchange resins were compared for their abilities to separate soybean phosphatidylcholine (PC). D113-III resin was\\u000a selected for PC purification among ten resins tested. The optimum PC adsorption conditions were: concentration of PC solution,\\u000a 3 mg\\/mL; pH of PC solution, 7.5; and adsorption flow rate, 1 mL\\/min. The optimum PC desorption conditions were: eluent, 95%\\u000a ethanol aqueous solution; and elution flow rate,

  15. Sudden death of distillability in qutrit-qutrit systems

    E-print Network

    Wei Song; Lin Chen; Shi-Liang Zhu

    2009-08-01

    We introduce the concept of distillability sudden death, i.e., free entangled states can evolve into non-distillable (bound entangled or separable) states in finite time under local noise. We describe the phenomenon through a specific model of local dephasing noise and compare the behavior of states in terms of the Bures fidelity. Then we propose a few methods to avoid distillability sudden death of states under (general) local dephasing noise, so that free entangled states can be robust against decoherence. Moreover, we find that bound entangled states are unstable in the limit of infinite time.

  16. Leadership in wolf, Canis lupus, packs

    USGS Publications Warehouse

    Mech, L.D.

    2000-01-01

    I examine leadership in Wolf (Canis lupus) packs based on published observations and data gathered during summers from 1986 to 1998 studying a free-ranging pack of Wolves on Ellesmere Island that were habituated to my presence. The breeding male tended to initiate activities associated with foraging and travel, and the breeding female to initiate, and predominate in, pup care and protection. However, there was considerable overlap and interaction during these activities such that leadership could be considered a joint function. In packs with multiple breeders, quantitative information about leadership is needed.

  17. Accurate measurements of infinite dilution activity coefficients using gas chromatography with static-wall-coated open-tubular columns.

    PubMed

    Xu, Qianqian; Su, Baogen; Luo, Xinyi; Xing, Huabin; Bao, Zongbi; Yang, Qiwei; Yang, Yiwen; Ren, Qilong

    2012-11-01

    Wall-coated open-tubular (WCOT) columns provide higher column efficiency and lower solute interfacial adsorption effect than packed columns. However, previous efforts used to measure the infinite dilution activity coefficient (?(?)) via a chromatographic technique have used packed columns, because the low carrier gas flow rate (U) and the small stationary phase amount (n(2)) in WCOT columns raise large errors. By rationally revising the ?(?)-calculation equation for static-wall-coated open-tubular column, we observed that U and n(2) are not necessarily needed and the resulting error could be reduced, and WCOT column gas chromatography subsequently became a superior method for the accurate ?(?) determination. In this study, we validate our revised ?(?)-calculation equation by measuring ?(?) in an ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate system, in which 55 organic compounds covering a wide range of functional groups were used as probe solutes and their ?(?) values in the ionic liquid were determined at 40.0, 50.0, and 60.0 °C. Experimental error analysis shows that our revised equation remarkably reduces the error compared to the common ?(?)-calculation equation. Our data is consistent with previously reported values obtained via other techniques, which further proves the credibility of our revised equation. The accurately determined ?(?) values can be directly used to calculate the partial molar excess enthalpy, selectivity, and capacity, which will benefit for the rapid screening of solvents (especially ionic liquids) in separation approaches. PMID:23039405

  18. 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.

    PubMed

    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. PMID:26091787

  19. The separation of glycerides by liquid-liquid column partition chromatography

    Microsoft Academic Search

    B. C. Black; E. G. Hammond

    1963-01-01

    A liquid-liquid partition chromatography method was developed to separate triglycerides. The solvent was a two phase mixture\\u000a of acetone, heptane, and water supported on silane treated celite. A study was made of the best means for equilibrating the\\u000a solvents and support, packing the column, and introducing the sample. The effect of various operating variables such as flow\\u000a rate, sample size,

  20. New method for monitoring of adsorption column saturation and regeneration II: on-line measurement

    Microsoft Academic Search

    N. D. Del Vecchio; S. Barghi; S. Primak; J. E. Puskas

    2004-01-01

    A new method suitable for the on-line monitoring of adsorption column saturation\\/regeneration cycles was developed based on the discovery that the electrical resistance of packed bed adsorbents changes dramatically upon adsorption and returns to its original value upon desorption. This change can be measured reliably and reproducibly. The two systems studied on-line in real time were methyl chloride (MeCl) adsorption

  1. Use of computers for multicomponent distillation calculations 

    E-print Network

    Sullivan, Samuel Lane

    1959-01-01

    for Total Reflux in One Section of a Column Restrictions. Calculational Procedure Illustrative Examples Conclusions 33 35 38 45 Table of Notation Bibliography. Appendix. 46 49 52 LIST OF ILLUSTRATIONS Figure Page 1. Diagram of a... of 8 at the Operating Reflux 59 ' 6O LIST OF TABLES Table Page I-a Equilibrium Data for Example Equi. librium Data for Examples 1~ 2~ 4-7. 61 62 Enthalpy Data. 63 III-a Statement of Examples ? Composition of Feeds III-b Statement of Examples...

  2. Stripper column of Ni-Cr-Mo alloy is inert to ammonia at 270°F

    Microsoft Academic Search

    G. Hunt; A. Gaines

    1987-01-01

    The Eastern Steel Division of Armco, Inc., in Ashland, Kentucky performs on-site carbonization of coal to produce coke. The coke oven gas is processed into an acceptable fuel. The final step in the processing of this gas is the stripping of ammonia from methylethylamine by steam distillation at about 270°F. The original ammonia stripping column was fabricated in 1978 with

  3. Membrane augmented distillation to separate solvents from water

    DOEpatents

    Huang, Yu; Baker, Richard W.; Daniels, Rami; Aldajani, Tiem; Ly, Jennifer H.; Alvarez, Franklin R.; Vane, Leland M.

    2012-09-11

    Processes for removing water from organic solvents, such as ethanol. The processes include distillation to form a rectified overhead vapor, compression of the rectified vapor, and treatment of the compressed vapor by two sequential membrane separation steps.

  4. Synthesis and design of optimal thermal membrane distillation networks 

    E-print Network

    Nyapathi Seshu, Madhav

    2006-10-30

    Thermal membrane distillation is one of the novel separation methods in the process industry. It involves the simultaneous heat and mass transfer through a hydrophobic semipermeable membrane through the use of thermal ...

  5. EVALUATION OF A VACUUM DISTILLER FOR PERFORMING METHOD 8261 ANALYSES

    EPA Science Inventory

    Vacuum distillation uses a specialized apparatus. This apparatus has been developed and patented by the EPA. Through the Federal Technology Transfer Act this invention has been made available for commercialization. Available vendors for this instrumentation are being evaluated. ...

  6. Energy Use in Distillation Operation: Nonlinear Economic Effects

    E-print Network

    White, D. C.

    2010-01-01

    Distillation operations are major consumers of energy, by some estimates comprising forty percent of the energy usage in the refining and chemicals industry. Obtaining the maximum energy efficiency from this unit operation is obviously very...

  7. Absorption Cycle Fundamentals and Applications Guidelines for Distillation Energy Savings

    E-print Network

    Erickson, D. C.; Davidson, W. F.

    1984-01-01

    The absorption cycle offers one of the most economic and widely applicable technologies for waste heat upgrading. It can use off-the-shelf hardware that is available now, at any required capacity rating. Fractional distillations, as a class...

  8. Entanglement distillation by means of k-extendible maps

    E-print Network

    Pankowski, L; Horodecki, M; Smith, G

    2011-01-01

    It is known that from entangled states which have positve partial transpose it is not possible to distill maximally entangled state by local operations and classical communication (LOCC). A long-standing problem is whether all states with non-positive partial transpose can be distilled. In this paper we attack this question using a larger class of operations than LOCC operations. Namely, we consider k-extendible operations - those, whose Choi-Jamiolkowski state is k-extendible. We obtain, in particular, that this class is unexpectedly powerful - e.g. capable of distilling even completely product states. We also perform numerical studies of distillation of Werner states by those maps, which imply, that if we raise the extension index k in parallel with raising the numebr of copies, they are not that powerful anymore.

  9. Heat Recovery in Distillation by Mechanical Vapor Recompression

    E-print Network

    Becker, F. E.; Zakak, A. I.

    consumed by the chemical and petro chemical industries is used in separation pro cesses. (1) Distillation is one process area where large energy reductions often can be achieved. (2) Numerous studies have identified a number of al ternatives...

  10. Energy Efficiency in Cryogenic Fractionation Through Distributive Distillation

    E-print Network

    Carradine, C. R.; McCue, R. H.

    The Advanced Recovery System (ARS) is a patented process that uses the principle of distributed distillation to achieve energy efficiency in the olefins process. This paper describes the concept of ARS and how, by integrating the chill...

  11. Process for the preparation of hydrocarbon oil distillates

    SciTech Connect

    Van Dongen, R. H.; Stork, W. H. J.

    1985-02-19

    Distillates are prepared from asphaltenes-rich feeds by a process comprising subjecting the feed to solvent deasphalting, and subjecting the resulting asphaltic bitumen fraction to a combination of catalytic hydrotreating and thermal cracking.

  12. 7 CFR 920.13 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Definitions § 920.13 Pack. ...arrangement, size, weight, count, or grade of a quantity of kiwifruit in a particular type and size of container, or any...

  13. 7 CFR 29.3538 - Packing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Standards Official Standard Grades for Dark Air-Cured Tobacco (u.s. Types 35, 36, 37 and Foreign Type 95) § 29.3538 Packing. A lot of tobacco...

  14. 7 CFR 29.3538 - Packing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Standards Official Standard Grades for Dark Air-Cured Tobacco (u.s. Types 35, 36, 37 and Foreign Type 95) § 29.3538 Packing. A lot of tobacco...

  15. 7 CFR 29.3538 - Packing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Standards Official Standard Grades for Dark Air-Cured Tobacco (u.s. Types 35, 36, 37 and Foreign Type 95) § 29.3538 Packing. A lot of tobacco...

  16. 7 CFR 29.3538 - Packing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Standards Official Standard Grades for Dark Air-Cured Tobacco (u.s. Types 35, 36, 37 and Foreign Type 95) § 29.3538 Packing. A lot of tobacco...

  17. 7 CFR 29.3538 - Packing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Standards Official Standard Grades for Dark Air-Cured Tobacco (u.s. Types 35, 36, 37 and Foreign Type 95) § 29.3538 Packing. A lot of tobacco...

  18. Finite Element Simulation of Dense Wire Packings

    E-print Network

    R. Vetter; F. K. Wittel; N. Stoop; H. J. Herrmann

    2012-07-03

    A finite element program is presented to simulate the process of packing and coiling elastic wires in two- and three-dimensional confining cavities. The wire is represented by third order beam elements and embedded into a corotational formulation to capture the geometric nonlinearity resulting from large rotations and deformations. The hyperbolic equations of motion are integrated in time using two different integration methods from the Newmark family: an implicit iterative Newton-Raphson line search solver, and an explicit predictor-corrector scheme, both with adaptive time stepping. These two approaches reveal fundamentally different suitability for the problem of strongly self-interacting bodies found in densely packed cavities. Generalizing the spherical confinement symmetry investigated in recent studies, the packing of a wire in hard ellipsoidal cavities is simulated in the frictionless elastic limit. Evidence is given that packings in oblate spheroids and scalene ellipsoids are energetically preferred to spheres.

  19. Groundwater well with reactive filter pack

    DOEpatents

    Gilmore, T.J.; Holdren, G.R. Jr.; Kaplan, D.I.

    1998-09-08

    A method and apparatus are disclosed for the remediation of contaminated soil and ground water wherein a reactive pack material is added to the annular fill material utilized in standard well construction techniques. 3 figs.

  20. Groundwater well with reactive filter pack

    DOEpatents

    Gilmore, Tyler J. (Pasco, WA); Holdren, Jr., George R. (Kennewick, WA); Kaplan, Daniel I. (Richland, WA)

    1998-01-01

    A method and apparatus for the remediation of contaminated soil and ground water wherein a reactive pack material is added to the annular fill material utilized in standard well construction techniques.

  1. Metal tubing/frit with a sintered frit of silica particles and a chromatography column with such tubing/frits.

    PubMed

    Cheong, Won Jo

    2005-02-25

    This study is about the metal tubing/frit prepared by treating a powdered silica with a strong base, drying it, scrubbing it into powders, putting it in the tip of metal tubing at a proper depth, and sintering the powders to form a durable sintered frit. This study is also about a liquid chromatographic column prepared by installing the metal tubing/frit at the column inlet and outlet unions and by placing the column main body tubing packed with a stationary phase between the two unions. The metal tubing/frit made according to the description is easily replaced and fixed without disassembling the column when it is necessary. The column of this design could be a cheap substitute for the conventional microcolumn. PMID:15794576

  2. DISTILL: Learning Domain-Specific Planners by Example Elly Winner ELLY@CS.CMU.EDU

    E-print Network

    Veloso, Manuela M.

    DISTILL: Learning Domain-Specific Planners by Example Elly Winner ELLY@CS.CMU.EDU Manuela Veloso present the DISTILL algorithm for learning dsPlanners automatically from example plans. DISTILL converts that the dsPlan- ners automatically learned by DISTILL com- pactly represent its domain-specific planning ex

  3. Finding limiting flows of batch extractive distillation with interval Erika R. Fritsa,b*

    E-print Network

    Csendes, Tibor

    1/25 Finding limiting flows of batch extractive distillation with interval arithmetic Erika R@inf.u-szeged.hu Abstract Feasibility study on batch extractive distillation is based on analyzing profile maps distillation, feasibility, bifurcation, profile map Introduction Batch extractive distillation (BED) is a unit

  4. 27 CFR 1.83 - Acquiring or receiving distilled spirits in bulk for addition to wine.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...distilled spirits in bulk for addition to wine. 1.83 Section 1.83 Alcohol...NONINDUSTRIAL USE OF DISTILLED SPIRITS AND WINE, BULK SALES AND BOTTLING OF DISTILLED...distilled spirits in bulk for addition to wine. Persons holding permits as...

  5. Regions of continuous rectification in systems divided into distillation regions

    SciTech Connect

    Balashov, M.I.; Grishunin, A.V.; Serafimov, L.A.

    1985-07-01

    The authors present the mechanisms of formation of regions of continuous clear rectification in three-component azeotropic systems of any complexity divided into distillation regions. The limitations of the process for all types of clear rectification have been determined. They have noted the phenomena of intersection of sets in which the rectification process develops as a function of the type of the specified separation. The phenomenon of transfer through the separating manifold of distillation has been pointed out.

  6. Activating NPPT distillation with an infinitesimal amount of bound entanglement

    E-print Network

    Karl Gerd H. Vollbrecht; Michael M. Wolf

    2002-01-23

    We show that bipartite quantum states of any dimension, which do not have a positive partial transpose, become 1-distillable when one adds an infinitesimal amount of bound entanglement. To this end we investigate the activation properties of a new class of symmetric bound entangled states of full rank. It is shown that in this set there exist universal activator states capable of activating the distillation of any NPPT state.

  7. Real option theory from finance to batch distillation

    Microsoft Academic Search

    Vicente Rico-ramírez; Urmila M. Diwekar; Benoit Morel

    2003-01-01

    Batch distillation processes have gained renewed interest because of the recent development in small-scale industries producing high-value-added, low-volume specialty chemicals. The flexibility and unsteady state nature of batch distillation constitute a challenge for the designer. A particularly difficult problem is the optimal control problem involving open loop solution for the reflux ratio profile. This is because of the complexity of

  8. The amplified distillation of methyl esters of fatty acids

    Microsoft Academic Search

    A. W. Weitkamp

    1947-01-01

    Summary  Amplified distillation is a useful technique for the quantitative analysis of mixtures of fatty acid esters, especially for\\u000a the detection and estimation of minor components and for the analysis of small samples. The amplified distillation of free\\u000a fatty acids is largely limited to qualitative work on account of the formation of azeotropes with mineral oils.

  9. Software For Nearly Optimal Packing Of Cargo

    NASA Technical Reports Server (NTRS)

    Fennel, Theron R.; Daughtrey, Rodney S.; Schwaab, Doug G.

    1994-01-01

    PACKMAN computer program used to find nearly optimal arrangements of cargo items in storage containers, subject to such multiple packing objectives as utilization of volumes of containers, utilization of containers up to limits on weights, and other considerations. Automatic packing algorithm employed attempts to find best positioning of cargo items in container, such that volume and weight capacity of container both utilized to maximum extent possible. Written in Common LISP.

  10. Process for removing naphthenic acids from petroleum distillates

    SciTech Connect

    Danzik, M.

    1987-01-06

    A liquid extraction process is described for removing naphthenic acids from naphthenic acid containing petroleum distillates boiling within the range of about 180/sup 0/-600/sup 0/C. and having an acid number of at least about 0.2 which process comprises the steps of: (a) intimately contacting the petroleum distillates with a solvent consisting essentially of methanol, water, and about from 2-20 wt. % ammonia and having a methanol: water ratio in the range of about from 0.2 to 3 parts by weight of methanol per part by weight of water and using an ammonia to petroleum distillate ratio of about 0.1-1 part by weight of ammonia per 100 parts by weight of the petroleum distillate. This selectively extracts the naphthenic acids into the solvent and yielding an immiscible two-phase liquid mixture, one of which is naphthenic acid-rich solvent phase and the other of which is a substantially napthenic acid-free petroleum distillate phase; and (b) separating and respectively recovering the naphtenic acid-rich solvent phase and petroleum distillate phase.

  11. Process for the preparation of light hydrocarbon distillates by hydrocracking and catalytic cracking

    SciTech Connect

    DeVries, A.F.; Stork, W.H.J.

    1989-08-22

    This patent describes a process for the preparation of a gasoline range petroleum distillate from a vacuum heavy hydrocarbon oil distillate. It comprises: passing at least a portion of the vacuum heavy hydrocarbon oil distillate to a hydrocracking zone to hydrocrack the distillate into a product stream comprising a hydrocracked distillate residue having an initial boiling point of at least 300{sup 0}C; passing the hydrocracked distillate to a distillation separation zone to separate and recover the residue; passing the residue to a catalytic cracking zone to catalytically crack the residue; passing at least a portion of the vacuum heavy oil distillate prior to hydrocracking to the catalytic cracking to catalytically crack the vacuum heaving oil distillate; withdrawing the gasoline range petroleum distillate from the catalytic cracking zone.

  12. Dense periodic packings of tetrahedra with small repeating units

    E-print Network

    Yoav Kallus; Veit Elser; Simon Gravel

    2010-03-19

    We present a one-parameter family of periodic packings of regular tetrahedra, with the packing fraction $100/117\\approx0.8547$, that are simple in the sense that they are transitive and their repeating units involve only four tetrahedra. The construction of the packings was inspired from results of a numerical search that yielded a similar packing. We present an analytic construction of the packings and a description of their properties. We also present a transitive packing with a repeating unit of two tetrahedra and a packing fraction $\\frac{139+40\\sqrt{10}}{369}\\approx0.7194$.

  13. Integrated column arithmetic according to progressive schematisation

    Microsoft Academic Search

    A. Treffers

    1987-01-01

    Following an introduction on the relation between column arithmetic and mental arithmetic in connection with the development of pocket calculators and computers, the characteristics of progressive schematisation are described with regard to column multiplication and column division. In this way, an image is formed of the specific characteristics of this approach to column arithmetic set against the background of traditional

  14. Dynamic adsorption of organic solvent vapors onto a packed bed of activated carbon cloth

    SciTech Connect

    Huang, C.C.; Lin, Y.C.; Lu, F.C. [Chung Cheng Inst. of Tech., Taoyuan (Taiwan, Province of China). Dept. of Applied Chemistry] [Chung Cheng Inst. of Tech., Taoyuan (Taiwan, Province of China). Dept. of Applied Chemistry

    1999-02-01

    The adsorption behavior of organic compound vapors onto a packed bed of activated carbon cloth (ACC) has been investigated. Three types of ACCs have been employed: KF1500, FT200-20, and E-ACC. The volatile organic compounds (VOCs) used in this study are acetone, dichloromethane, acrylonitrile, and n-hexane. The operating parameters studied are temperature of adsorber, weight of ACC, relative humidity of fluid, inlet concentration of VOCs, and total volumetric flow rate of gas stream. A simple theoretical model, originally introduced by Yoon and Nelson, has been utilized to simulate the breakthrough curve of VOC vapor on an adsorption column packed with activated carbon cloth. A modified model is proposed to predict the adsorption behavior of an adsorber at different temperatures.

  15. Application of new packing material in endoscopic nasal surgery

    PubMed Central

    Yin, Haiying; Han, Fei; Cui, Zhaoyang

    2015-01-01

    Objective: To show the efficacy and comfort of pneumatic bag packing after the endoscopic nasal surgery. Pneumatic bag packing may be recommendable in terms of comfort and efficacy after endoscopic nasal surgery. Significant findings: There were statistical significant differences between the pneumatic bag packing and the expansive sponge packing regarding subjective symptoms and objective findings after surgery. Conclusions: Pneumatic bag packing may be recommendable in terms of comfort and efficacy after endoscopic nasal surgery. PMID:25785173

  16. Architecture-specific packing for virtex-5 FPGAs

    Microsoft Academic Search

    Taneem Ahmed; Paul D. Kundarewich; Jason Helge Anderson; Brad L. Taylor; Rajat Aggarwal

    2008-01-01

    We consider packing in the commercial FPGA context and examine the speed, performance and power trade-offs associ- ated with packing in a state-of-the art FPGA - the Xilinx R VirtexTM-5 FPGA. Two aspects of packing are discussed: 1) packing for general logic blocks, and 2) packing for large IP blocks. Virtex-5 logic blocks contain dual-output 6-input look-up-tables (LUTs). Such LUTs

  17. Interactions of human serum albumin with a modified poly(vinyl alcohol) gel packing for high-performance liquid chromatography

    Microsoft Academic Search

    Tohru Suzuki; Naka Muroi; Tsugikazu Tomono

    1989-01-01

    —The interactions of human serum albumin (HSA) with a poly(vinyl alcohol) gel packing (Asahipak GS-520) for high-performance liquid chromatography of proteins were investigated. Under certain conditions, the elution of HSA from the GS-520 column was retarded and its chromatogram was split into two peaks, indicating weak adsorption of HSA onto the gels and also the existence of two subfractions, i.e.

  18. [Preparation and physicochemical properties for zirconia as high performance liquid chromatographic packing materials].

    PubMed

    Dun, Huijuan; Yu, Wenxiao; Zhao, Huimin; Chen, Liren

    2006-01-01

    There has been an increasing importance in the application of zirconia as column packing material for high performance liquid chromatography (HPLC) because of its excellent chemical, thermal, and mechanical stabilities as well as bioanalysis suitability. Zirconia spheres could be synthesized by polymerization-induced colloid aggregation (PICA), oil emulsion methods (OEM), or spray-dry method. It has been found that preparative procedure of zirconia support can affect its chromatographic behavior significantly. The review analyzes the relationship between zirconia packings' physicochemical properties and their preparative procedures. Specific surface area, pore structure, pore volume, pore size distribution, and particle size distribution are discussed in detail. At present, zirconia has not become highly competitive because of its limitations such as small specific surface area and pore volume, broad pore size distribution and particle distribution, and unfavorable pore structure. The review also describes silica-zirconia composite HPLC materials prepared by sol-gel method, coating and co-precipitation procedure. However, their chemical stability as HPLC column packings was suspicious because of the residual silica on the material surface. Furthermore, the study showed that zircon (ZrSiO4) is present in all silica-coated zirconia or silica-zirconia composites. It could be deduced that co-existence of more than one crystallines on the material surface could produce chemical heterogeneity, resulting in complex chromatographic separation mechanism. It leads a conclusion that a new synthetic way is needed for preparing zirconia-based HPLC packings with ideal chromatographic parameters. A novel material with higher specific surface area and pore volume, good pore structure, narrower pore size distribution and more uniform particle size distribution was prepared by layer-by-layer self-assembly technique (LbL SA), consisting of micrometer-sized silica spheres as core and nanometer-size zirconia particles as surface coating. The chemical stability of the material is as good as that of zirconia, and its specific surface area is as high as that of silica. PMID:16827321

  19. Sound wave velocities in dry and lubricated granular packings packings: numerical simulations and experiments

    E-print Network

    Paris-Sud XI, Université de

    influences the material stiffness more than its density, is notably higher in lubricated packings. 1 INTRODUCTION The mechanical properties of granular packings are sensitive to fine geometric details of the medium, the granular medium is effectively a homogeneous continuum to the prop- agating wave, while

  20. Deterioration of organic packing materials commonly used in air biofiltration: effect of VOC-packing interactions.

    PubMed

    Lebrero, Raquel; Estrada, José M; Muñoz, Raúl; Quijano, Guillermo

    2014-05-01

    The abiotic deterioration of three conventional organic packing materials used in biofiltration (compost, wood bark and Macadamia nutshells) caused by their interaction with toluene (used as a model volatile organic compound) was here studied. The deterioration of the materials was evaluated in terms of structural damage, release of co-substrates and increase of the packing biodegradability. After 21 days of exposure to toluene, all packing materials released co-substrates able to support microbial growth, which were not released by the control materials not exposed to toluene. Likewise, the exposure to toluene increased the packing material biodegradability by 26% in wood bark, 20% in compost and 17% in Macadamia nutshells. Finally, scanning electron microscopy analysis confirmed the deterioration in the structure of the packing materials evaluated due to the exposure to toluene, Macadamia nutshells being the material with the highest resistance to volatile organic compound attack. PMID:24603032