Science.gov

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. Distillation Column Modeling Tools

    SciTech Connect

    2001-09-01

    Advanced Computational and Experimental Techniques will Optimize Distillation Column Operation. Distillation is a low thermal efficiency unit operation that currently consumes 4.8 quadrillion BTUs of energy...

  3. 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.

  4. Packing columns for capillary electrochromatography.

    PubMed

    Coln, L A; Maloney, T D; Fermier, A M

    2000-07-28

    Considering the current interest in capillary electrochromatography (CEC), performed in packed columns, we present the different methods used to pack capillary columns for use in CEC. General considerations on column packing are given and the column fabrication process is discussed in sufficient detail to allow instruction to those who are not experienced in the field. Five different packing methods are discussed to deliver packing material into the capillary column from a practical view point: slurry pressure packing, packing with supercritical CO2, electrokinetic packing, using centripetal forces, and packing by gravity. Entrapment of particulate material by sintering and sol-gel technology is also mentioned. Although slurry pressure packing procedures are most common, higher separation efficiencies are obtained using other packing approaches. Electrokinetic packing seems to be the simplest technique to deliver the packing material into the capillary columns. Nevertheless, as with the other packing techniques, skill and experience are required to complete all the steps involved in the fabrication of packed columns for CEC. PMID:10961303

  5. Microfabricated packed gas chromatographic column

    DOEpatents

    Kottenstette, Richard; Matzke, Carolyn M.; Frye-Mason, Gregory C.

    2003-12-16

    A new class of miniaturized gas chromatographic columns has been invented. These chromatographic columns are formed using conventional micromachining techniques, and allow packed columns having lengths on the order of a meter to be fabricated with a footprint on the order of a square centimeter.

  6. Tritium Isotope Separation Using Adsorption-Distillation Column

    SciTech Connect

    Fukada, Satoshi

    2005-07-15

    In order to miniaturize the height of a distillation tower for the detritiation of waste water from fusion reactors, two experiments were conducted: (1) liquid frontal chromatography of tritium water eluting through an adsorption column and (2) water distillation using a column packed with adsorbent particles. The height of the distillation tower depends on the height equivalent to a theoretical plate, HETP, and the equilibrium isotope separation factor, {alpha}{sub H-T}{sup equi}. The adsorption action improved not only HETP but also {alpha}{sub H-T}{sup equi}. Since the adsorption-distillation method proposed here can shorten the tower height with keeping advantages of the distillation, it may bring an excellent way for miniaturizing the distillation tower to detritiate a large amount of waste water from fusion reactors.

  7. Method for packed column separations and purifications

    DOEpatents

    Holman, David A.; Bruckner-Lea, Cynthia J.; Brockman, Fred J.; Chandler, Darrell P.

    2006-08-15

    The invention encompasses a method of packing and unpacking a column chamber. A mixture of a fluid and a matrix material are introduced through a column chamber inlet so that the matrix material is packed within a column chamber to form a packed column. The column chamber having the column chamber inlet or first port for receiving the mixture further has an outlet port and an actuator port. The outlet port is partially closed for capturing the matrix material and permitting the fluid to flow therepast by rotating relative one to the other of a rod placed in the actuator port. Further rotation relative one to the other of the rod and the column chamber opens the outlet and permits the matrix material and the fluid to flow therethrough thereby unpacking the matrix material from the column chamber.

  8. Final Report, Distillation Column Flooding Predictor

    SciTech Connect

    George E. Dzyacky

    2003-05-31

    The Flooding Predictor is an advanced process control strategy comprising a patented pattern-recognition methodology that identifies pre-flood patterns discovered to precede flooding events in distillation columns. The grantee holds a U.S. patent on the modeling system. The technology was validated at the Separations Research Program, The University of Texas at Austin under a grant from the U. S. Department of Energy, Inventions & Innovation Program. Distillation tower flooding occurs at abnormally high vapor and/or liquid rates. The loss in tray efficiencies is attributed to unusual behavior of liquid inventories inside the column leading to conditions of flooding of the space in between trays with liquid. Depending on the severity of the flood condition, consequences range from off spec products to equipment damage and tower shutdown. This non-intrusive pattern recognition methodology, processes signal data obtained from existing column instrumentation. Once the pattern is identified empirically, it is modeled and coded into the plant's distributed control system. The control system is programmed to briefly "unload" the tower each time the pattern appears. The unloading takes the form of a momentary reduction in column severity, e.g., decrease bottom temperature, reflux or tower throughput. Unloading the tower briefly at the pre-flood state causes long-term column operation to become significantly more stable - allowing an increase in throughput and/or product purity. The technology provides a wide range of value between optimization and flooding. When a distillation column is not running at capacity, it should be run in such a way ("pushed") that optimal product purity is achieved. Additional benefits include low implementation and maintenance costs, and a high level of console operator acceptance. The previous commercial applications experienced 98% uptime over a four-year period. Further, the technology is unique in its ability to distinguish between different flooding mechanisms within the same tower, e.g., liquid and jet flooding.

  9. A Versatile, Automatic Chromatographic Column Packing Device

    ERIC Educational Resources Information Center

    Barry, Eugene F.; And Others

    1977-01-01

    Describes an inexpensive apparatus for packing liquid and gas chromatographic columns of high efficiency. Consists of stainless steel support struts, an Automat Getriebmotor, and an associated three-pulley system capable of 10, 30, and 300 rpm. (MLH)

  10. Continuous and Batch Distillation in an Oldershaw Tray Column

    ERIC Educational Resources Information Center

    Silva, Carlos M.; Vaz, Raquel V.; Santiago, Ana S.; Lito, Patricia F.

    2011-01-01

    The importance of distillation in the separation field prompts the inclusion of distillation experiments in the chemical engineering curricula. This work describes the performance of an Oldershaw column in the rectification of a cyclohexane/n-heptane mixture. Total reflux distillation, continuous rectification under partial reflux, and batch

  11. Continuous and Batch Distillation in an Oldershaw Tray Column

    ERIC Educational Resources Information Center

    Silva, Carlos M.; Vaz, Raquel V.; Santiago, Ana S.; Lito, Patricia F.

    2011-01-01

    The importance of distillation in the separation field prompts the inclusion of distillation experiments in the chemical engineering curricula. This work describes the performance of an Oldershaw column in the rectification of a cyclohexane/n-heptane mixture. Total reflux distillation, continuous rectification under partial reflux, and batch…

  12. An Automated Distillation Column for the Unit Operations Laboratory

    ERIC Educational Resources Information Center

    Perkins, Douglas M.; Bruce, David A.; Gooding, Charles H.; Butler, Justin T.

    2005-01-01

    A batch distillation apparatus has been designed and built for use in the undergraduate unit operations laboratory course. The column is fully automated and is accompanied by data acquisition and control software. A mixture of 1­-propanol and 2-­propanol is separated in the column, using either a constant distillate rate or constant composition…

  13. An Automated Distillation Column for the Unit Operations Laboratory

    ERIC Educational Resources Information Center

    Perkins, Douglas M.; Bruce, David A.; Gooding, Charles H.; Butler, Justin T.

    2005-01-01

    A batch distillation apparatus has been designed and built for use in the undergraduate unit operations laboratory course. The column is fully automated and is accompanied by data acquisition and control software. A mixture of 1-propanol and 2-propanol is separated in the column, using either a constant distillate rate or constant composition

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

    SciTech Connect

    Yang, Dali; Orler, Bruce; Tornga, Stephanie; Welch, Cindy

    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.

  15. Gas chromatographic analysis of wet gas in packed capillary column

    SciTech Connect

    Amirov, K.M.; Chepegina, E.K.; Zakharova, N.V.; Zeninskaya, F.Z.

    1985-07-01

    These authors have investigated the feasibility of separation and quantitative determination of wet gas components in a packed capillary column in combination with a standard thermal conductivity detector. One chart plots the height of an equivalent theoretical plate as a function of the volume flow rate of carrier gas for the packed capillary column, and another chart shows the chromatic separation of wet gas in the column. The authors conclude that packed capillary columns permit a threefold reduction in the time required to separate the components of wet gas from catalytic cracking, in comparison with a standard packed column.

  16. Flubendiamide transport through packed soil columns.

    PubMed

    Das, Shaon Kumar; Mukherjee, Irani

    2012-02-01

    Flubendiamide insecticide is widely used in Indian subtropical condition to control lepidopteron pests mainly in rice and cotton. The present study reports leaching behaviour of flubendiamide, N(2)-[1,1-dimethyl-2-(methylsulfonyl)ethyl]-3-iodo-N(1)-[2-methyl-4-[1,2,2,2-tetrafluoro-1 (trifluoromethyl)ethyl] phenyl]-1,2-benzene dicarboxamide, in packed soil columns under different rainfall conditions. Flubendiamide did not leach out of the 25 cm long soil columns even after percolating water equivalent to 462.18 mm rainfall. After leaching with water equivalent to 462.18 mm rainfall, in analytical grade treatment, 68.06% of the recovered flubendiamide was the major amount present in 5-10 cm depth whereas in the formulation 67.22% of the recovered flubendiamide was confined to 0-5 cm depth. Results revealed that with percolating 160 mL of water residues of desiodo flubendiamide detected up to 20-25 cm layer along with 9.47% residues in this layer, indicating that metabolite is more mobile as compared to analytical grade flubendiamide and 39.35% SC formulation. Formulation slowed the downward mobility of flubendiamide in soil column. Flubendiamide is slightly mobile in sandy loam soil, but desiodo flubendiamide is relatively more mobile and may leach into ground water. PMID:22002178

  17. Temperature cascade control of distillation columns

    SciTech Connect

    Wolff, E.A.; Skogestad, S.

    1996-02-01

    This paper examines how difficult control tasks are enhanced by introducing secondary measurements, creating control cascades. Temperature is much used as secondary measurement because of cheap implementation and quick and accurate response. Distillation is often operated in this manner due to slow or lacking composition measurements, although the benefits have hardly been investigated closely, especially for multivariable control applications. The authors therefore use distillation as the example when quantifying improvements in interaction and disturbance rejection. They also give analytical expressions for the secondary controller gain. The improvements are reached through simple cascade operation of the control system and require no complicated estimator function.

  18. Compact sieve-tray distillation column for ammonia-water absorption heat pump: Part 1 -- Design methodology

    SciTech Connect

    Anand, G.; Erickson, D.C.

    1999-07-01

    The distillation column is a key component of ammonia-water absorption units including advanced generator-absorber heat exchange (GAX) cycle heat pumps. The design of the distillation column is critical to unit performance, size, and cost. The distillation column can be designed with random packing, structured packing, or various tray configurations. A sieve-tray distillation column is the least complicated tray design and is less costly than high-efficiency packing. Substantial literature is available on sieve tray design and performance. However, most of the correlations and design recommendations were developed for large industrial hydrocarbon systems and are generally not directly applicable to the compact ammonia-water column discussed here. The correlations were reviewed and modified as appropriate for this application, and a sieve-tray design model was developed. This paper presents the sieve-tray design methodology for highly compact ammonia-water columns. A conceptual design of the distillation column for an 8 ton vapor exchange (VX) GAX heat pump is presented, illustrating relevant design parameters and trends. The design process revealed several issues that have to be investigated experimentally to design the final optimized rectifier. Validation of flooding and weeping limits and tray/point efficiencies are of primary importance.

  19. Stabilization of the Circulation Flow of the Cryogenic Distillation Column

    NASA Astrophysics Data System (ADS)

    Juromskiy, V. M.

    Two-circuit system of automatic stabilization of the hydrodynamics of the cryogenic distillation column is considered. Control system eliminates flooding/depletion of column in long-term mode of operation when the accuracy of stabilization of the circulation flow is better than 1%.

  20. Miniature Distillation Column for Producing LOX From Air

    NASA Technical Reports Server (NTRS)

    Rozzi, Jay C.

    2006-01-01

    The figure shows components of a distillation column intended for use as part of a system that produces high-purity liquid oxygen (LOX) from air by distillation. (The column could be easily modified to produce high-purity liquid nitrogen.) Whereas typical industrial distillation columns for producing high-purity liquid oxygen and/or nitrogen are hundreds of feet tall, this distillation column is less than 3 ft (less than about 0.9 m) tall. This column was developed to trickle-charge a LOX-based emergency oxygen system (EOS) for a large commercial aircraft. A description of the industrial production of liquid oxygen and liquid nitrogen by distillation is prerequisite to a meaningful description of the present miniaturized distillation column. Typically, such industrial production takes place in a chemical processing plant in which large quantities of high-pressure air are expanded in a turboexpander to (1) recover a portion of the electrical power required to compress the air and (2) partially liquefy the air. The resulting two-phase flow of air is sent to the middle of a distillation column. The liquid phase is oxygen-rich, and its oxygen purity increases as it flows down the column. The vapor phase is nitrogen-rich and its nitrogen purity increases as it flows up the column. A heater or heat exchanger, commonly denoted a reboiler, is at the bottom of the column. The reboiler is so named because its role is to reboil some of the liquid oxygen collected at the bottom of the column to provide a flow of oxygen-rich vapor. As the oxygen-rich vapor flows up the column, it absorbs the nitrogen in the down-flowing liquid by mass transfer. Once the vapor leaves the lower portion of the column, it interacts with down-flowing nitrogen liquid that has been condensed in a heat exchanger, commonly denoted a condenser, at the top of the column. Liquid oxygen and liquid nitrogen products are obtained by draining some of the purified product at the bottom and top of the column, respectively. Because distillation is a mass-transfer process, the purity of the product(s) can be increased by increasing the effectiveness of the mass-transfer process (increasing the mass-transfer coefficient) and/or by increasing the available surface area for mass transfer through increased column height. The diameter of a distillation column is fixed by pressure-drop and mass-flow requirements. The approach taken in designing the present distillation column to be short yet capable of yielding a product of acceptably high purity was to pay careful attention to design details that affect mass-transfer processes.

  1. Aspects of column fabrication for packed capillary electrochromatography.

    PubMed

    Angus, P D; Demarest, C W; Catalano, T; Stobaugh, J F

    2000-07-28

    Various parameters have been evaluated to develop a process for optimization of column manufacture for packed capillary electrochromatography (CEC). Spherisorb ODS-1 was packed into 75 microm I.D. capillaries to establish a standard set of packing conditions to afford high-performance columns free of voids. Numerous silica-based packing materials including porous and non-porous reversed-phase and ion-exchange phases were employed to evaluate the applicability of the standard conditions. Success of column manufacture and performance demonstrate a relationship to the colligative properties of the packing materials under the applied conditions. Frequently encountered difficulties arising from inadequate column conditioning and void formation in the packed bed are identified and discussed. PMID:10961326

  2. Experimental results of hydrogen distillation at the low power cryogenic column for the production of deuterium depleted hydrogen

    SciTech Connect

    Alekseev, I.; Fedorchenko, O.; Kravtsov, P.; Vasilyev, A.; Vznuzdaev, M.

    2008-07-15

    The Deuterium Removal Unit (DRU) has been designed and built at the Petersburg Nuclear Physics Inst. (PNPI) to produce isotopically pure hydrogen with deuterium content less than 1 ppm. The cryogenic distillation column of 2.2 cm inner diameter and 155 cm packing height is the main element of the DRU. Column performances at different hydrogen distillation operating modes have been measured. The height equivalent to theoretical plate (HETP) for the column is 2.2 cm and almost constant over a wide range of vapour flow rates. Deuterium depleted hydrogen with a deuterium content of less than 0.1 ppm was produced in required quantity. (authors)

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

    SciTech Connect

    Robson, M.; Johnson, B.R.; Mitchell, S.C.

    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.

  4. Optimal packing characteristics of rolled, continuous stationary-phase columns.

    PubMed

    Li, Chenghong; Ladisch, Christine M; Yang, Yiqi; Hendrickson, Richard; Keim, Craig; Mosier, Nathan; Ladisch, Michael R

    2002-01-01

    Rolled, continuous stationary phases were constructed by tightly rolling and inserting a whole textile fabric into a chromatography column. This work reports the column performance, in terms of plate height, void fraction, and resolution, of 10 cellulose-based fabrics. The relation between fabric structural properties of yarn diameter, fabric count, fabric compressibility, and column performance are quantitated. General requirements, including reproducibility of packing, for choosing fabrics to make a good SEC column are identified. This research showed that the packed columns have an optimal mass of fabric that minimizes plate height and maximizes resolution, in a manner that is consistent with chromatography theory. Mass of material packed is then an important column parameter to consider when optimizing columns for the rapid desalting of proteins. Proteins were completely separated from salt and glucose in less than 8 min at a pressure drop less than 500 psi on the rolled, continuous stationary-phase columns. These results, together with stability and reproducibility, suggest potential industrial applications for cellulose-based rolled, continuous stationary-phase columns where speed is a key parameter in the production process. PMID:11934301

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

    SciTech Connect

    Unger, K.K.; Hallman, M.; Ranis-Jansen, R.

    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}.

  6. Immobilization of enzymes on polytetrafluoroethylene particles packed in HPLC columns

    SciTech Connect

    Danielson, N.D.; Siergiej, R.W.

    1981-08-01

    The use of polytetrafluoroethylene particles packed in short, high performance liquid chromatography columns for the immobilization of enzymes is examined. In particular, lactate dehydrogenase chosen as a model system was investigated with regard to activity and stability when immobilized on polytetrafluoroethylene. (Refs. 7).

  7. 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.

  8. Systems For Column-Based Separations, Methods Of Forming Packed Columns, And Methods Of Purifying Sample Components.

    DOEpatents

    Egorov, Oleg B.; O'Hara, Matthew J.; Grate, Jay W.; Chandler, Darrell P.; Brockman, Fred J.; Bruckner-Lea, Cynthia J.

    2004-08-24

    The invention encompasses systems for column-based separations, methods of packing and unpacking columns and methods of separating components of samples. In one aspect, the invention includes a method of packing and unpacking a column chamber, comprising: a) packing a matrix material within a column chamber to form a packed column; and b) after the packing, unpacking the matrix material from the column chamber without moving the column chamber. In another aspect, the invention includes a system for column-based separations, comprising: a) a fluid passageway, the fluid passageway comprising a column chamber and a flow path in fluid communication with the column chamber, the flow path being obstructed by a retaining material permeable to a carrier fluid and impermeable to a column matrix material suspended in the carrier fluid, the flow path extending through the column chamber and through the retaining material, the flow path being configured to form a packed column within the column chamber when a suspension of the fluid and the column matrix material is flowed along the flow path; and b) the fluid passageway extending through a valve intermediate the column chamber and the retaining material.

  9. Systems For Column-Based Separations, Methods Of Forming Packed Columns, And Methods Of Purifying Sample Components

    DOEpatents

    Egorov, Oleg B.; O'Hara, Matthew J.; Grate, Jay W.; Chandler, Darrell P.; Brockman, Fred J.; Bruckner-Lea, Cynthia J.

    2006-02-21

    The invention encompasses systems for column-based separations, methods of packing and unpacking columns and methods of separating components of samples. In one aspect, the invention includes a method of packing and unpacking a column chamber, comprising: a) packing a matrix material within a column chamber to form a packed column; and b) after the packing, unpacking the matrix material from the column chamber without moving the column chamber. In another aspect, the invention includes a system for column-based separations, comprising: a) a fluid passageway, the fluid passageway comprising a column chamber and a flow path in fluid communication with the column chamber, the flow path being obstructed by a retaining material permeable to a carrier fluid and impermeable to a column matrix material suspended in the carrier fluid, the flow path extending through the column chamber and through the retaining material, the flow path being configured to form a packed column within the column chamber when a suspension of the fluid and the column matrix material is flowed along the flow path; and b) the fluid passageway extending through a valve intermediate the column chamber and the retaining material.

  10. Systems for column-based separations, methods of forming packed columns, and methods of purifying sample components

    DOEpatents

    Egorov, Oleg B.; O'Hara, Matthew J.; Grate, Jay W.; Chandler, Darrell P.; Brockman, Fred J.; Bruckner-Lea, Cynthia J.

    2000-01-01

    The invention encompasses systems for column-based separations, methods of packing and unpacking columns and methods of separating components of samples. In one aspect, the invention includes a method of packing and unpacking a column chamber, comprising: a) packing a matrix material within a column chamber to form a packed column; and b) after the packing, unpacking the matrix material from the column chamber without moving the column chamber. In another aspect, the invention includes a system for column-based separations, comprising: a) a fluid passageway, the fluid passageway comprising a column chamber and a flow path in fluid communication with the column chamber, the flow path being obstructed by a retaining material permeable to a carrier fluid and impermeable to a column matrix material suspended in the carrier fluid, the flow path extending through the column chamber and through the retaining material, the flow path being configured to form a packed column within the column chamber when a suspension of the fluid and the column matrix material is flowed along the flow path; and b) the fluid passageway extending through a valve intermediate the column chamber and the retaining material.

  11. [A novel multiple-channel apparatus for packing capillary chromatographic column and its application].

    PubMed

    Lü, Yayao; Hao, Feiran; Wang, Huanhuan; Fu, Bin; Qian, Xiaohong; Zhang, Yangjun

    2015-11-01

    A novel multiple-channel apparatus for packing capillary chromatographic column was designed and manufactured for packing six capillary chromatographic columns with close column efficiency at the same time. Briefly, it consists of a magnetic stirrer, a liquid chromatographic pump and a multiple-channel can. The reagents used for preparing ODS (C18) slurry and stirring condition of the magnetic stirrer were optimized in the study. Two batches of capillary chromatographic columns were packed under the optimum condition, and these packed capillary chromatographic columns were evaluated in the terms of peak capacity, sequence coverage, retention times of three peptide ions and column pressure using the tryptic digest of a bovine serum albumin (BSA) and detected by LC-MS in electrospray ionization (ESI) mode. The experimental results showed that the six capillary chromatographic columns packed at the same time had close column efficiencies, however, the column efficiencies of twelve capillary chromatographic columns packed at two times were significantly different. In addition, there was no significant column efficiency difference when packing one or six capillary chromatographic columns at the same time. The multiple-channel apparatus designed by us is simple, time-saving, and can be applied to pack capillary chromatographic columns with similar column efficiencies, thus it is of evident advantage over traditional one-channel apparatus. PMID:26939361

  12. Axial development and radial non-uniformity of flow in packed columns.

    PubMed

    Park, Jaekeun C; Raghavan, Karthik; Gibbs, Stephen J

    2002-02-01

    Flow inhomogeneity and axial development in low-pressure chromatographic columns have been studied by magnetic resonance imaging velocimetry. The columns studied included (a) an 11.7-mm I.D. column packed with either 50 microm diameter porous polyacrylamide, or 99 or 780 microm diameter impermeable polystyrene beads, and (b) a 5-mm I.D. column commercially packed with 10 microm polymeric beads. The packing methods included gravity settling, slurry packing, ultrasonication, and dry packing with vibration. The magnetic resonance method used averaged apparent fluid velocity over both column cross-sections and fluid displacements greater than one particle diameter and hence permits assessment of macroscopic flow non-uniformities. The results confirm that now non-uniformities induced by the conical distributor of the 11.7-mm I.D. column or the presence of voids at the column entrance relax on a length scale of the column radius. All of the 11.7-mm I.D. columns examined exhibit near wall channeling within a few particle diameters of the wall. The origins of this behavior are demonstrated by imaging of the radial dependence of the local porosity for a column packed with 780 microm beads. Columns packed with the 99-microm beads exhibit reduced flow in a region extending from ten to three-to-five particle diameters from the wall. This velocity reduction is consistent with a reduced porosity of 0.35 in this region as compared to approximately 0.43 in the bulk of the column. Ultrasonicated and dry-packed columns exhibit enhanced flow in a region located between approximately eight and 20 particle diameters from the wall. This enhancement maybe caused by packing density inhomogeneity and/or particle size segregation caused by vibration during the packing process. No significant non-uniformities on length scales of 20 microm or greater were observed in the commercially packed column packed with 10 microm particles. PMID:11860146

  13. Catalytic distillation process

    DOEpatents

    Smith, L.A. Jr.

    1982-06-22

    A method is described for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C[sub 4] feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.

  14. Catalytic distillation process

    DOEpatents

    Smith, Jr., Lawrence A.

    1982-01-01

    A method for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C.sub.4 feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.

  15. Packed column supercritical fluid chromatography of isomeric polypeptide pairs.

    PubMed

    Patel, M A; Riley, F; Wang, J; Lovdahl, M; Taylor, L T

    2011-05-01

    The characterization and determination of peptides is of great importance in the pharmaceutical industry as is the ability to rapidly perform targeted determinations of bioactive peptides in complex matrices. The purpose of the presented work is to assess the feasibility of packed column supercritical fluid chromatography (SFC) for the separation of two-pairs of water soluble peptides of identical mass, composition and charge that differ only in amino acid sequence. Upon evaluating a variety of conditions, trifluoroacetic acid (HTFA) in conjunction with methanol as the modifier proved to be, in general, the most successful mobile phase additive for elution of the two isomeric peptide pairs from all nitrogenous stationary phases. In contrast, water and ammonium acetate gave distorted peak shapes and therefore proved to be less satisfactory as neutral additives. The basic additive, iso-propylamine (IPAm), coupled with HA-Pyridine yielded the highest resolution factor for the complete study. Aminopropyl and HA-Pyridine columns with 5 μm particle size and 60 Å pore size were found to be best for resolution of each peptide pair. Bare silica and phenyl-hexyl stationary phases did not afford any separation. The primary roles of the carbon dioxide and methanol modifier are believed to provide (a) stationary phase solvation and (b) peptide solubility and transport; while, HTFA is postulated to fully protonate each peptide and form ion pairs between its conjugate base and cationic peptide analyte. The separation process, therefore, is best viewed as ion pair supercritical fluid chromatography (IP-SFC). For the case where IPAm gave good resolution on the HA-Pyridine column, the peptides are probably in the neutral state. PMID:21439574

  16. Output-feedback control of reactive batch distillation columns

    SciTech Connect

    Monroy-Loperena, R.; Alvarez-Ramirez, J.

    2000-02-01

    In this work, an output-feedback, control for the regulation of distillate purity via manipulations of the reflux ratio in reactive batch distillation is designed. The approach is based on an approximate model of the composition dynamics and makes use of a reduced-order observer to estimate the modeling error. An input/output linearizing feedback is proposed where the estimated modeling error is included to achieve robust tracking of a composition reference. It is shown that the resulting controller has the structure of a proportional-integral derivative (PID) controller with antireset windup. The controller performance is tested using a simulation example including strong uncertainties in the reaction model. An interesting finding is that the required reflux ratio policy to reach asymptotically a constant reference resembles the reflux ratio policy obtained from posing an optimization technique.

  17. Biocolloid transport in water saturated columns packed with sand

    NASA Astrophysics Data System (ADS)

    Syngouna, V. I.; Chrysikopoulos, C.

    2010-12-01

    Protection of groundwater supplies from microbial contamination necessitates a solid understanding of the factors controlling the migration and retention of pathogenic organisms (biocolloids) in the subsurface. The transport behavior of three waterborne pathogens (Escherichia coli, MS2, and ??174) was investigated using laboratory-scale columns packed with clean quartz sand. Various grain sizes and pore water velocities were examined. Though coliform bacteria and coliphages are used worldwide to indicate fecal pollution of groundwater, the various parameters controlling the transport of Escherichia coli MS2 and ??174 in the subsurface are not fully understood. In this study, the attachment behavior of Escherichia coli, MS2, and ??174 onto ultra-pure quartz sand were evaluated. The mass recoveries of the three biocolloids examined were found to be proportional to the sand size. The observed mass recoveries were in the order: Escherichia coli > ??174 > MS2. To assess the importance of biocolloid attachment, the single collector removal efficiency, and the collision efficiency were quantified using the classical colloid filtration theory. Our results indicate that the secondary energy minimum plays an important role in biocolloid deposition even for smaller biocolloid particles (e.g. viruses).

  18. Development of a mathematical model of a packed column for benzene removal from salt solutions

    SciTech Connect

    Georgeton, G.K.

    1989-12-31

    A mathematical model of a packed column was developed to describe the removal of benzene from radioactive salt solutions at the Savannah River Site. The model was developed from existing, generalized mass transfer correlations for randomly dumped packing, and the correlations were adapted for structured packing. Thermophysical data specific to the solutions of interest were incorporated into the model. Verification of the code was completed using operating data from stripping columns at other locations.

  19. Development of a mathematical model of a packed column for benzene removal from salt solutions

    SciTech Connect

    Georgeton, G.K.

    1989-01-01

    A mathematical model of a packed column was developed to describe the removal of benzene from radioactive salt solutions at the Savannah River Site. The model was developed from existing, generalized mass transfer correlations for randomly dumped packing, and the correlations were adapted for structured packing. Thermophysical data specific to the solutions of interest were incorporated into the model. Verification of the code was completed using operating data from stripping columns at other locations.

  20. 3D printed porous media columns with fine control of column packing morphology.

    PubMed

    Fee, Conan; Nawada, Suhas; Dimartino, Simone

    2014-03-14

    In this paper we demonstrate, for the first time, the use of 3D printing (also known as additive manufacturing or rapid prototyping) to create porous media with precisely defined packing morphologies, directly from computer aided design (CAD) models. We used CAD to design perfectly ordered beds with octahedral beads (115 μm apothem) packed in a simple cubic configuration and monoliths with hexagonal channels (150 μm apothem) in parallel and herringbone arrangements. The models were then printed by UV curing of acrylonitrile-butadiene-styrene powder layers. Each porous bed was printed at 1.0, 1.5 and 2.0 mL volumes, within a complete column, including internal flow distributors and threaded 10-32 flow connectors. Close replication of CAD models was achieved. The resultant individual octahedral beads were highly uniform in size, with apothems of 113.6±1.9 μm, while the monolith hexagonal cross-section channels had apothems of 148.2±2.0 μm. Residence time distribution measurements show that the beds largely behaved as expected from their design void volumes. Radial and fractal flow distributor designs were also tested. The former displayed poor flow distribution in parallel and herringbone pore columns, while the fractal distributors provided uniform flow distribution over the entire cross section. The results show that 3D printing is a feasible method for producing precisely controlled porous media. We expect our approach to revolutionize not only fundamental studies of flow in porous media but methods of chromatography column production. PMID:24529407

  1. Heat Transfer Study of Heat-Integrated Distillation Column (HIDiC) Using Simulation Techniques

    NASA Astrophysics Data System (ADS)

    Pulido, Jeffrey León; Martínez, Edgar Leonardo; Wolf, Maria Regina; Filho, Rubens Maciel

    2011-08-01

    Separation processes is largely used in petroleum refining and alcohol industries. Distillation columns consume a huge amount of energy in industrial process. Therefore, the concept of Heat-Integrated Distillation Column (HIDiC) was studied using simulation techniques in order to overcome this drawback. In this configuration the column is composed for two concentric sections called rectifying and stripping. The heat transfer is conducted from the rectifying section (which works at higher pressure and temperature) to the stripping section (which works at lower pressure and temperature) using the heat present in the process and decreasing the energy charge required by the reboiler. The HIDiC column offers great potential to reduce energy consumption compared to conventional columns. However, the complexity of the internal configuration requires the development of rigorous works that enable a better understanding of the column operation. For this reason, techniques of simulation were used through of computational software. The current work presents a heat transfer study in a concentric stage of a HIDiC column. The results obtained by Aspen Plus and CFD simulation showed the internal heat transfer in a concentric tray as a promissory configuration in order to decrease energy consumption in distillation processes.

  2. Separation of natural product using columns packed with Fused-Core particles.

    PubMed

    Yang, Peilin; Litwinski, George R; Pursch, Matthias; McCabe, Terry; Kuppannan, Krishna

    2009-06-01

    Three HPLC columns packed with 3 microm, sub-2 microm, and 2.7 microm Fused-Core (superficially porous) particles were compared in separation performance using two natural product mixtures containing 15 structurally related components. The Ascentis Express C18 column packed with Fused-Core particles showed an 18% increase in column efficiency (theoretical plates), a 76% increase in plate number per meter, a 65% enhancement in separation speed and a 19% increase in back pressure compared to the Atlantis T3 C18 column packed with 3 microm particles. Column lot-to-lot variability for critical pairs in the natural product mixture was observed with both columns, with the Atlantis T3 column exhibiting a higher degree of variability. The Ascentis Express column was also compared with the Acquity BEH column packed with sub-2 microm particles. Although the peak efficiencies obtained by the Ascentis Express column were only about 74% of those obtained by the Acquity BEH column, the 50% lower back pressure and comparable separation speed allowed high-efficiency and high-speed separation to be performed using conventional HPLC instrumentation. PMID:19425022

  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. Modified method to improve the design of Petlyuk distillation columns

    PubMed Central

    2014-01-01

    Background A response surface analysis was performed to study the effect of the composition and feeding thermal conditions of ternary mixtures on the number of theoretical stages and the energy consumption of Petlyuk columns. A modification of the pre-design algorithm was necessary for this purpose. Results The modified algorithm provided feasible results in 100% of the studied cases, compared with only 8.89% for the current algorithm. The proposed algorithm allowed us to attain the desired separations, despite the type of mixture and the operating conditions in the feed stream, something that was not possible with the traditional pre-design method. The results showed that the type of mixture had great influence on the number of stages and on energy consumption. A higher number of stages and a lower consumption of energy were attained with mixtures rich in the light component, while higher energy consumption occurred when the mixture was rich in the heavy component. Conclusions The proposed strategy expands the search of an optimal design of Petlyuk columns within a feasible region, which allow us to find a feasible design that meets output specifications and low thermal loads. PMID:25061476

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

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

  6. GOBF-ARMA based model predictive control for an ideal reactive distillation column.

    PubMed

    Seban, Lalu; Kirubakaran, V; Roy, B K; Radhakrishnan, T K

    2015-11-01

    This paper discusses the control of an ideal reactive distillation column (RDC) using model predictive control (MPC) based on a combination of deterministic generalized orthonormal basis filter (GOBF) and stochastic autoregressive moving average (ARMA) models. Reactive distillation (RD) integrates reaction and distillation in a single process resulting in process and energy integration promoting green chemistry principles. Improved selectivity of products, increased conversion, better utilization and control of reaction heat, scope for difficult separations and the avoidance of azeotropes are some of the advantages that reactive distillation offers over conventional technique of distillation column after reactor. The introduction of an in situ separation in the reaction zone leads to complex interactions between vapor-liquid equilibrium, mass transfer rates, diffusion and chemical kinetics. RD with its high order and nonlinear dynamics, and multiple steady states is a good candidate for testing and verification of new control schemes. Here a combination of GOBF-ARMA models is used to catch and represent the dynamics of the RDC. This GOBF-ARMA model is then used to design an MPC scheme for the control of product purity of RDC under different operating constraints and conditions. The performance of proposed modeling and control using GOBF-ARMA based MPC is simulated and analyzed. The proposed controller is found to perform satisfactorily for reference tracking and disturbance rejection in RDC. PMID:25956185

  7. The setup of an extraction system coupled to a hydrogen isotopes distillation column

    SciTech Connect

    Zamfirache, M.; Bornea, A.; Stefanescu, I.; Bidica, N.; Balteanu, O.; Bucur, C.

    2008-07-15

    Among the most difficult problems of cryogenic distillation one stands apart: the extraction of the heavy fraction. By an optimal design of the cycle scheme, this problem could be avoided. A 'worst case scenario' is usually occurring when the extracted fraction consists of one prevalent isotope such as hydrogen and small amounts of the other two hydrogen isotopes (deuterium and/or tritium). This situation is further complicated by two parameters of the distillation column: the extraction flow rate and the hold-up. The present work proposes the conceptual design of an extraction system associated to the cryogenic distillation column used in hydrogen separation processes. During this process, the heavy fraction (DT, T{sub 2}) is separated, its concentration being the highest at the bottom of the distillation column. From this place the extraction of the gaseous phase can now begin. Being filled with adsorbent, the extraction system is used to temporarily store the heavy fraction. Also the extraction system provides samples for the gas Chromatograph. The research work is focused on the existent pilot plant for tritium and deuterium separation from our institute to validate the experiments carried out until now. (authors)

  8. Micro-fabricated packed gas chromatography column based on laser etching technology.

    PubMed

    Sun, J H; Guan, F Y; Zhu, X F; Ning, Z W; Ma, T J; Liu, J H; Deng, T

    2016-01-15

    In this work, a micro packed gas chromatograph column integrated with a micro heater was fabricated by using laser etching technology (LET) for analyzing environmental gases. LET is a powerful tool to etch deep well-shaped channels on the glass wafer, and it is the most effective way to increase depth of channels. The fabricated packed GC column with a length of over 1.6m, to our best knowledge, which is the longest so far. In addition, the fabricated column with a rectangular cross section of 1.2mm (depth)×0.6mm (width) has a large aspect ratio of 2:1. The results show that the fabricated packed column had a large sample capacity, achieved a separation efficiency of about 5800 plates/m and eluted highly symmetrical Gaussian peaks. PMID:26726935

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

    SciTech Connect

    Cheong, W.; Barton, P.I.

    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.

  10. Mobility of spiromesifen in packed soil columns under laboratory conditions.

    PubMed

    Mate, Ch Jamkhokai; Mukherjee, Irani; Das, Shaon Kumar

    2014-11-01

    On percolating water equivalent to 1,156mm of rainfall, spiromesifen formulation did not leach out of 25-cm long columns, and 62.7% of this was recovered in 5-10-cm soil depth. In columns treated with the analytical grade, 52.40% of the recovered spiromesifen was confined to 0-5-cm soil depth, with 0.04% in leachate fraction, suggesting high adsorption in soil. Results revealed that percolating 400mL of water, residues of enol metabolite of spiromesifen was detected up to 20-25-cm soil layer, with 23.50% residues of spiromesifen in this layer and 1.73% in the leachate fraction indicating that metabolite is more mobile as compared to the parent compound. Results suggested a significant reduction in leaching losses of enol metabolite in amended soil columns with 5% nano clay, farmyard manure (FYM), and vermicompost. No enol spiromesifen was recovered in the leachate in columns amended with nano clay, vermicompost, and FYM; however, 85.30, 70.5, and 65.40%, respectively, was recovered from 0-5cm-soil depth of column after percolating water equivalent to 1,156mm of rainfall. Spiromesifen formulation is less mobile in sandy loam soil than analytical grade spiromesifen. The metabolite, enol spiromesifen, is relatively more mobile than the parent compound and may leach into groundwater. The study suggested that amendments were very effective in reducing the downward mobility of enol metabolite in soil column. Further, it resulted in greater retention of enol metabolite in the amendment application zone. PMID:25060860

  11. Numerical simulations of heat transfer in a packed column: comparison of microwave and convective heating

    NASA Astrophysics Data System (ADS)

    Cherbański, Robert

    2015-05-01

    This paper presents a comparative study on heat transfer in a packed column. Two methods of heating are considered: microwave and convective. Transient one-dimensional mathematical models were proposed to describe the both alternatives. To account for significant differences in the temperatures between the gas and solid phase a heterogeneous model was applied in the modelling. The numerical simulations were carried out for different operating conditions. The effects of the gas inlet temperature and the microwave power, the bed porosity, the penetration depth of microwaves and the gas velocity were examined. The simulation results were compared on the basis of the time profiles of the average bed temperature and the outlet gas temperature. The same electric power utilized in the microwave heated packed column and the convective heated packed column was established as the key criterion for the comparisons. The compared profiles intersect indicating the time ranges in which the one or the other solution provides higher temperature of the bed. It was displayed that the microwave heated packed column should be preferred when longer heating times are required. In turn, the convective heated packed column is the better choice when shorter heating times are needed.

  12. Kinetic performance evaluation and perspectives of contemporary packed column capillary electrochromatography.

    PubMed

    De Smet, Seppe; Lynen, Frederic

    2014-08-15

    Capillary electrochromatography (CEC) is in essence a highly efficient and fast separation technique but practical constraints limit the current performance, robustness and routine implementation of the technique. In this work the kinetic performance limit (KPL) curve was used to evaluate commercial packed column CEC; this firstly in order to assess the broader applicability of the kinetic plot approach in electrodriven chromatographic techniques, and secondly to allow a more general unbiased comparison with HPLC performance. Evaluations were performed with a mixture of well retained and electrophoretically neutral phenones, to allow the observation of only chromatographic processes. Initial CEC retention time irreproducibility issues were solved by applying high acetonitrile content (80%) in the mobile phase, and solute retention was increased by increasing the phenone chain length. Comparison was performed with HPLC, with a column packed with an identical stationary phase to allow measurement of the performance under optimal conditions, and not with μ-LC on the CEC column as extra column peak broadening phenomena would thereby negatively affect the μ-LC performance. This comparison demonstrated that current HPLC performance largely outcompetes what is achievable with contemporary packed column CEC. Interestingly, significantly improved CEC performance could be obtained at lower temperatures (10°C) indicating a persistent degree of joule heating phenomena taking place in the contemporary packed column (100μm) CEC approach. Effective suppression of the latter opens possibilities for increasing the applicable voltage and outperforming HPLC and UHPLC. PMID:24958031

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

    SciTech Connect

    Cheong, W.; Barton, P.I.

    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.

  14. Dynamics and control of a heterogeneous azeotropic distillation column: Conventional control approach

    SciTech Connect

    Chien, I.L.; Wang, C.J.; Wong, D.S.H.

    1999-02-01

    In this work, bifurcation analysis and dynamic simulation were used to investigate the optimum conventional control strategy of an isopropyl alcohol (IPA), cyclohexane (CyH), and water (H{sub 2}O) heterogeneous azeotropic column. Steady-state process analysis shows that the optimal operation point should be located at a critical reflux, a transition point at which the distillation path switches from a route that passes through the IPA + H{sub 2}O azeotrope to one that passes through the IPA + CyH azeotrope. A good control strategy must be able to maintain a steady column temperature profile that shows a plateau near 70 C to ensure passage around the IPA + CyH azeotrope. An inverse double-loop control strategy is proposed based on principal component analysis. This scheme is capable of maintaining the desired column temperature profile given all kinds of feed disturbances, thus keeping the product IPA purity at the desired level.

  15. A hybrid feedback linearizing-Kalman filtering control algorithm for a distillation column.

    PubMed

    Jana, Amiya Kumar; Samanta, Amar Nath

    2006-01-01

    This paper studies the design of a discrete-time multivariable feedback linearizing control (FLC) structure. The control scheme included (i) a transformer [also called the input/output (I/O) linearizing state feedback law] that transformed the nonlinear u-y to a linearized v-y system, (ii) a closed-loop observer [extended Kalman filter (EKF)], which estimated the unmeasured states, and (iii) a conventional proportional integral (PI) controller that was employed around the v-y system as an external controller. To avoid the estimator design complexity, the design of EKF for a binary distillation column has been performed based on a reduced-order compartmental distillation model. Consequently, there is a significant process/predictor mismatch, and despite this discrepancy, the EKF estimated the required states of the simulated distillation column precisely. The FLC in conjunction with EKF (FLC-EKF) and that coupled with a measured composition-based reduced-order open-loop observer (FLC-MCROOLO) have been synthesized. The FLC structures showed better performance than the traditional proportional integral derivative controller. In practice, the presence of uncertainties and unknown disturbances are common, and in such situations, the proposed FLC-EKF control scheme ensured the superiority over the FLC-MCROOLO law. PMID:16480113

  16. 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 μm 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 μm 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 μm superficially porous particles compared to sub-2 μm fully porous particles. PMID:25456605

  17. Simulation of the dynamic packing behavior of preparative chromatography columns via discrete particle modeling.

    PubMed

    Dorn, Martin; Hekmat, Dariusch

    2016-03-01

    Preparative packed-bed chromatography using polymer-based, compressible, porous resins is a powerful method for purification of macromolecular bioproducts. During operation, a complex, hysteretic, thus, history-dependent packed bed behavior is often observed but theoretical understanding of the causes is limited. Therefore, a rigorous modeling approach of the chromatography column on the particle scale has been made which takes into account interparticle micromechanics and fluid-particle interactions for the first time. A three-dimensional deterministic model was created by applying Computational Fluid Dynamics (CFD) coupled with the Discrete Element Method (DEM). The column packing behavior during either flow or mechanical compression was investigated in-silico and in laboratory experiments. A pronounced axial compression-relaxation profile was identified that differed for both compression strategies. Void spaces were clearly visible in the packed bed after compression. It was assumed that the observed bed inhomogeneity was because of a force-chain network at the particle scale. The simulation satisfactorily reproduced the measured behavior regarding packing compression as well as pressure-flow dependency. Furthermore, the particle Young's modulus and particle-wall friction as well as interparticle friction were identified as crucial parameters affecting packing dynamics. It was concluded that compaction of the chromatographic bed is rather because of particle rearrangement than particle deformation. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 32:363-371, 2016. PMID:26588806

  18. Pre-packed reverse phase columns for isolation of complex lipids synthesized from radioactive precursors

    SciTech Connect

    Figlewicz, D.A.; Nolan, C.E.; Singh, I.N.; Jungalwala, F.B.

    1985-01-01

    Pre-packed reverse phase columns (Bond Elut) were used for the separation of complex lipids, such as phosphatidylcholine, cerebrosides, sulfatides, and gangliosides, from their respective water-soluble radioactive precursors after their in vitro biosynthesis. After an incubation in vitro, the entire reaction mixture is passed through the column, where complex lipids are retained and the hydrophilic radioactive precursors are washed away from the column. The retained lipids are then eluted with a more nonpolar organic solvent. The procedure is shown to be simpler and more efficient than the normally used Folch partitioning method or other procedures.

  19. Achiral and chiral analysis of camazepam and metabolites by packed-column supercritical fluid chromatography.

    PubMed

    Wang, M Z; Klee, M S; Yang, S K

    1995-03-10

    Supercritical fluid chromatography, using carbon dioxide as the mobile phase and ethanol as a modifier, has been applied to the analysis of products formed in rat liver microsomal metabolism of racemic camazepam, a hypnotic/anxiolytic drug in clinical use. An achiral (amino) column and a chiral (Chiralcel OD-H) column were used. The results suggest that achiral and chiral packed-column supercritical fluid chromatography gives a shorter analysis time and higher selectivity and efficiency than achiral and chiral stationary-phase high-performance liquid chromatography in the analysis of camazepam and its derivatives. PMID:7795784

  20. Continuous aqueous two-phase extraction of human antibodies using a packed column.

    PubMed

    Rosa, P A J; Azevedo, A M; Sommerfeld, S; Bcker, W; Aires-Barros, M R

    2012-01-01

    The performance of a pilot scale packed differential contactor was evaluated for the continuous counter-current aqueous two-phase extraction (ATPE) of human immunoglobulin G (IgG) from a Chinese hamster ovary (CHO) cells supernatant (CS) enriched with pure protein. Preliminary studies have been firstly performed in order to select the dispersed phase (phosphate-rich or polyethylene glycol 3350 Da (PEG)-rich phase) and the column packing material. The PEG-rich phase has been selected as the dispersed phase and the stainless steel as the preferred material for the column packing bed since it was not wetted preferentially by the selected dispersed phase. Hydrodynamic studies have been also performed, and the experimental results were successfully adjusted to the Richardson-Zaki and Msek equations, typically used for the conventional organic-aqueous two-phase systems. An experimental set-up combining the packed column with a pump mixer-settler stage showed to have the best performance and to be advantageous when compared to the IgG batch extraction. An IgG recovery yield of 85% could be obtained with about 50% of total contaminants and more than 85% of contaminant proteins removal. Mass transfer studies have revealed that the mass transfer was controlled by the PEG-rich phase. A higher efficiency could be obtained when using an extra pump mixer-settler stage and higher flow rates. PMID:22173005

  1. 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.

  2. Scrubbing in packed columns of gases from soda-regeneration boiler complexes

    SciTech Connect

    Kolev, N.N.; Paskalev, G.P.; Semkov, K.A.; Darakchiev, R.D.

    1988-01-01

    The treatment of gases from the soda-regeneration boilers in sulfate cellulose pulping plants is intended for the removal of dust and sulfur dioxide from the gases and for the recovery and utilization of their heat. In this paper the authors investigate the possibility of using columns of KhOLPAK horizontal sheet packings for cleaning the stack gases. The packings consist of sheets of punched and drawn metal arranged at fixed distances in a horizontal configuration. Spray nozzles are used to wet the surface area. Calculations and design parameters are carried out depicting the flow characteristics of the gases and sprays in both counterflow and concurrent flow scrubbers.

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

    SciTech Connect

    Cheong, W.; Barton, P.I.

    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.

  4. 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

  5. The calculation and interpretation of parametric transfer functions for binary distillation columns of the tray type

    NASA Astrophysics Data System (ADS)

    Edwards, J. B.; Tabrizi, M. H. N.

    1982-02-01

    A transfer function matrix model for long, symmetrical, binary distillation columns was derived completely analytically from assumptions for dynamic analysis. The model relates twin output composition changes to perturbations in the internal liquid and vapor flow rates. The model is intended for use in controller design and, being expressed in terms of plant parameters and operating conditions, provides useful common ground between control engineer and plant designer. Though derived precisely for a symmetrical plant, the model applies more generally as a good approximation. Experimental data is given supporting this claim. Inverse Nyquist loci are generated in precise and approximate form and shown to compare favorably with computed step responses. The responses accord broadly with previous, part empirical, part numerical research results.

  6. Separation of drugs by packed column supercritical fluid chromatography. 2. Antidepressants.

    PubMed

    Berger, T A; Wilson, W H

    1994-03-01

    Antidepressants can be rapidly and efficiently separated by packed-column supercritical fluid chromatography with a tertiary mobile phase. Ten antidepressants were nearly baseline resolved in < 6 min without programming. Calculated detection limits with a 5-microL injection volume were as low as 88 ppb. The effects of temperature, pressure, and modifier concentration on retention and selectivity were studied. Changing modifier concentration caused significant changes in selectivity. Several relationships between solute structure and selectivity changes were noted. PMID:8207669

  7. Research on the separation properties of empty-column gas chromatography (EC-GC) and conditions for simulated distillation (SIMDIS).

    PubMed

    Boczkaj, Grzegorz; Kamiński, Marian

    2013-10-01

    Previous studies have revealed it is possible to separate a high-boiling mixture by gas chromatography in empty fused-silica capillary tubing rather than in columns coated with stationary phase. Chromatographic separation occurs solely on the basis of the different boiling points of the substances separated. The high similarity of such separations to those in classic distillation seems advantageous when gas chromatography is used for simulated distillation. This paper presents results from further research on the separation properties of empty fused silica tubing. The efficiency of this chromatographic system has been examined. The usefulness of such conditions has been studied for simulated distillation, i.e. to determine the boiling-point distribution of complex mixtures, mainly petroleum fractions and products, on the basis of their retention relative to reference substances. The results obtained by use of empty-column gas chromatography (EC-GC) and by use of classical simulated distillation columns have been compared for solutes of different polarity. Studies revealed boiling points determined by EC-GC were more accurate than those obtained by the standard method of simulated distillation. PMID:23925798

  8. Column performance of granular activated carbon packed bed for Pb(II) removal.

    PubMed

    Dwivedi, Chandra P; Sahu, J N; Mohanty, C R; Mohan, B Raj; Meikap, B C

    2008-08-15

    The excessive release of lead from lead acid batteries, smelting plant into the environment is a major concern worldwide. Adsorption process is among the most effective techniques for lead removal from wastewater and activated carbon has been widely used as an adsorbent. In this paper an attempt has been made to investigate the adsorption behaviour of Pb(II) from aqueous systems onto granular activated carbon using the batch mode and continuous mode in a packed bed column with more successive service and regeneration. The experiments were performed at constant temperature and dimensions of column and packed bed of granular activated carbon with variation of flows through the bed and concentrations of lead solutions. Breakthrough points were found out for the adsorption of lead on the adsorbent using continuous-flow column operation by varying different operating parameters like hydraulic loading rate from 4 to 16 m(3)/h m(2) and feed concentrates from 20 to 60 mg/l. Granular activated carbon column regeneration using 0.5 M concentration of HNO(3) has been investigated. Results indicate encouraging performance towards removal of Pb(II). PMID:18249492

  9. Nitrate removal from groundwater in columns packed with reed and rice stalks.

    PubMed

    Qian, Jiazhong; Wang, Zhiping; Jin, Song; Liu, Yong; Chen, Tianhu; Fallgren, Paul H

    2011-10-01

    Nitrate leaching contaminates groundwater. The objective of this study was to determine if reed and rice stalks could enhance denitrification and reduce nitrate leaching into groundwater. Artificial groundwater spiked with nitrate and field groundwater samples were tested in the columns in sand reactors packed with either reed or rice stalks. The maximum nitrate removal rates were determined to be 1.93 and 1.97 mg nitrate-N l(-1) h(-1), respectively, in the reed and rice stalk-packed columns. The maximum nitrate-nitrogen removal rate in reactors packed with reed stalk was 1.33 mg nitrate-N l(-1) h(-1) when experimented with natural groundwater. Chemical oxygen demand consumption was higher when rice stalk (176.1 mg l(-1)) was used as the substrate, compared to reed stalk (35.2 mg l(-1)) at the same substrate dosage. No nitrite accumulation was detected during the test. The results demonstrate that agricultural byproducts, such as reed and rice stalks, may be used as substrate amendments for enhanced denitrification in natural settings, such as lakeside lagoons, ditches or wetlands. PMID:22329150

  10. Searching for Measures of Reversibility in Continuous Adsorption through Packed Bed Columns

    NASA Astrophysics Data System (ADS)

    Sidiras, Dimitris K.

    2009-08-01

    This work deals with searching for measures of after-process reversibility in continuous adsorption through packed bed columns. A methodology has been designed/developed under the form of an algorithmic procedure including 17 activity stages and 5 decision nodes. An implementation is presented concerning adsorption/desorption of methylene blue on pine sawdust. An Ideal Reversibility Index (IRI) and two Real Rreversibility Indices (RRIs) have been estimated after fitting kinetic adsorption/desorption models to experimental data. Last, the implications of applying an innovation are discussed in terms of techno-economic analysis.

  11. Packing of large-scale chromatography columns with irregularly shaped glass based resins using a stop-flow method

    PubMed Central

    Siu, Sun Chau; Chia, Celeste; Mok, Yanglin; Pattnaik, Priyabrata

    2014-01-01

    Rigid chromatography resins, such as controlled pore glass based adsorbents, offer the advantage of high permeability and a linear pressure-flow relationship irrespective of column diameter which improves process time and maximizes productivity. However, the rigidity and irregularly shaped nature of these resins often present challenges in achieving consistent and uniform packed beds as formation of bridges between resin particles can hinder bed consolidation. The standard flow-pack method when applied to irregularly shaped particles does not yield well-consolidated packed beds, resulting in formation of a head space and increased band broadening during operation. Vibration packing methods requiring the use of pneumatically driven vibrators are recommended to achieve full packed bed consolidation but limitations in manufacturing facilities and equipment may prevent the implementation of such devices. The stop-flow packing method was developed as an improvement over the flow-pack method to overcome these limitations and to improve bed consolidation without the use of vibrating devices. Transition analysis of large-scale columns packed using the stop-flow method over multiple cycles has shown a two- to three-fold reduction of change in bed integrity values as compared to a flow-packed bed demonstrating an improvement in packed bed stability in terms of the height equivalent to a theoretical plate (HETP) and peak asymmetry (As). PMID:25080096

  12. Separation of basic drugs by packed-column supercritical fluid chromatography. 3. Stimulants.

    PubMed

    Berger, T A; Wilson, W H

    1995-04-01

    A wide range of stimulants was rapidly and efficiently separated with symmetrical peak shapes with a tertiary supercritical mobile phase and a cyanopropyl liquid chromatography column. Compared with other drug families studied in this series, the stimulants exhibited a much broader range of retention. Several strong bases, including primary aliphatic amines, were easily eluted with a modified mobile phase. The stimulants were generally more retained than antipsychotic drugs. Compared with antidepressant drugs, a few stimulants behaved similarly, but most were more strongly retained. Modifier concentration proved to be the most effective means for changing both retention and selectivity. An over-the-counter eye drop solution (an aqueous buffer) was analyzed for tetrahydrozoline. The positive results with good peak shapes indicate that packed-column supercritical fluid chromatography is compatible with at least small aqueous samples. PMID:7629742

  13. 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.

  14. Effects of Gravity on Cocurrent Two-Phase Gas-Liquid Flows Through Packed Columns

    NASA Technical Reports Server (NTRS)

    Motil, Brian J.; Balakotaiah, Vemuri; Kamotani, Yasuhiro

    2001-01-01

    This work presents the experimental results of research on the influence of gravity on flow pattern transitions, pressure drop and flow characteristics for cocurrent gas-liquid two-phase flow through packed columns. The flow pattern transition data indicates that the pulse flow regime exists over a wider range of gas and liquid flow rates under reduced gravity conditions compared to normal gravity cocurrent down-flow. This is illustrated by comparing the flow regime transitions found in reduced gravity with the transitions predicted by Talmor. Next, the effect of gravity on the total pressure drop in a packed column is shown to depend on the flow regime. The difference is roughly equivalent to the liquid static head for bubbly flow but begins to decrease at the onset of pulse flow. As the spray flow regime is approached by increasing the gas to liquid ratio, the effect of gravity on pressure drop becomes negligible. Finally, gravity tends to suppress the amplitude of each pressure pulse. An example of this phenomenon is presented.

  15. Separation of drugs by packed column supercritical fluid chromatography. 1. Phenothiazine antipsychotics.

    PubMed

    Berger, T A; Wilson, W H

    1994-03-01

    Studies of speed, resolution, and sensitivity indicate packed column supercritical fluid chromatography is a viable technique for the analysis of antipsychotic drugs. Fourteen such drugs (mostly phenothiazines) were studied from a cyanopropyl liquid chromatography packed column with a tertiary mobile phase of carbon dioxide, methanol, and isopropylamine. An arbitrary mix of 10 components was baseline resolved in approximately 11 min. Detection limits were as low as 125 ppb, with a feasible 10-fold decrease. Without the isopropylamine in the mobile phase, none of the solutes eluted. With the additive, all produced symmetrical peaks and high efficiency (i.e., > 80% of theoretical). Changing modifier concentration was the most effective physical parameter for changing retention but had little effect on selectivity. Temperature changes had a modest effect on retention but provided surprisingly large changes in selectivity, with numerous peak reversals occurring over only a 30 degrees C temperature range. In addition, temperature programming was the most effective means to optimize resolution of the 10-component mix. No noticeable loss in efficiency accompanied the temperature programs. PMID:7911529

  16. 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.

  17. 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.

  18. 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

  19. Stable isotope fractionations during reactive transport of phosphate in packed-bed sediment columns

    NASA Astrophysics Data System (ADS)

    Jaisi, Deb P.

    2013-11-01

    Characterizing reactivity and fate of contaminants in subsurface environments that are isolated from direct visualization is a major challenge. Stable isotopes coupled with concentration could be used as a potential tool to quantitatively analyze the chemical variability of the contaminant during reactive transport processes in the subsurface environment. This study was aimed at determining whether abiotic reactions of phosphate during its transport involve fractionation of oxygen isotopes in phosphate (δ18Op). It included the effects of solution chemistry and hydrodynamics on δ18Op values during phosphate transport through a packed-bed column prepared by using natural sediment collected from the Cape Cod aquifer in Massachusetts. Results show that the isotopic fractionation between effluent and influent phosphate at early stage of transport could be ~ 1.3‰ at higher flow rates with isotopically-light phosphate (P16O4) preferentially retained in the sediment column. This fractionation, however, decreased and became insignificant as more phosphate passed through the column. Mobilization of phosphate initially sorbed onto sediments caused a large kinetic isotopic fractionation with isotopically-light phosphate preferentially remobilized from the sediment column, but over longer time periods, this fractionation decreased and became insignificant as well. These results collectively suggest that abiotic reactive transport processes exert minimal influence on the δ18Op composition of subsurface systems. Alternatively, fluctuation in flow rate and subsequent remobilization of phosphate could be detectable through transient changes in δ18Op values. These findings extend the burgeoning application of δ18Op to identify the different sources and geochemical processes of phosphate in the subsurface environments.

  20. Stable isotope fractionations during reactive transport of phosphate in packed-bed sediment columns.

    TOXLINE Toxicology Bibliographic Information

    Jaisi DP

    2013-11-01

    Characterizing reactivity and fate of contaminants in subsurface environments that are isolated from direct visualization is a major challenge. Stable isotopes coupled with concentration could be used as a potential tool to quantitatively analyze the chemical variability of the contaminant during reactive transport processes in the subsurface environment. This study was aimed at determining whether abiotic reactions of phosphate during its transport involve fractionation of oxygen isotopes in phosphate (δ(18)Op). It included the effects of solution chemistry and hydrodynamics on δ(18)Op values during phosphate transport through a packed-bed column prepared by using natural sediment collected from the Cape Cod aquifer in Massachusetts. Results show that the isotopic fractionation between effluent and influent phosphate at early stage of transport could be ~1.3‰ at higher flow rates with isotopically-light phosphate (P(16)O4) preferentially retained in the sediment column. This fractionation, however, decreased and became insignificant as more phosphate passed through the column. Mobilization of phosphate initially sorbed onto sediments caused a large kinetic isotopic fractionation with isotopically-light phosphate preferentially remobilized from the sediment column, but over longer time periods, this fractionation decreased and became insignificant as well. These results collectively suggest that abiotic reactive transport processes exert minimal influence on the δ(18)Op composition of subsurface systems. Alternatively, fluctuation in flow rate and subsequent remobilization of phosphate could be detectable through transient changes in δ(18)Op values. These findings extend the burgeoning application of δ(18)Op to identify the different sources and geochemical processes of phosphate in the subsurface environments.

  1. Stable isotope fractionations during reactive transport of phosphate in packed-bed sediment columns.

    PubMed

    Jaisi, Deb P

    2013-11-01

    Characterizing reactivity and fate of contaminants in subsurface environments that are isolated from direct visualization is a major challenge. Stable isotopes coupled with concentration could be used as a potential tool to quantitatively analyze the chemical variability of the contaminant during reactive transport processes in the subsurface environment. This study was aimed at determining whether abiotic reactions of phosphate during its transport involve fractionation of oxygen isotopes in phosphate (δ(18)Op). It included the effects of solution chemistry and hydrodynamics on δ(18)Op values during phosphate transport through a packed-bed column prepared by using natural sediment collected from the Cape Cod aquifer in Massachusetts. Results show that the isotopic fractionation between effluent and influent phosphate at early stage of transport could be ~1.3‰ at higher flow rates with isotopically-light phosphate (P(16)O4) preferentially retained in the sediment column. This fractionation, however, decreased and became insignificant as more phosphate passed through the column. Mobilization of phosphate initially sorbed onto sediments caused a large kinetic isotopic fractionation with isotopically-light phosphate preferentially remobilized from the sediment column, but over longer time periods, this fractionation decreased and became insignificant as well. These results collectively suggest that abiotic reactive transport processes exert minimal influence on the δ(18)Op composition of subsurface systems. Alternatively, fluctuation in flow rate and subsequent remobilization of phosphate could be detectable through transient changes in δ(18)Op values. These findings extend the burgeoning application of δ(18)Op to identify the different sources and geochemical processes of phosphate in the subsurface environments. PMID:24055952

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

    SciTech Connect

    Hideo Usui; Yuichi Niibori; Hitoshi Mimura; Osamu Tochiyama

    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)

  3. Packed-column supercritical fluid chromatography: Quantitative determination of uranium without liquid waste generation

    SciTech Connect

    Martin-Daguet, V.; Gasnier, P.; Caude, M.

    1997-02-01

    A new procedure for the determination of uranium by packed-column supercritical fluid chromatography is proposed. A nonfluorinated chelating agent selective for copper and uranium, the 2,6-diacetylpyridine bis(benzoylhydrazone), has been chosen. We have studied its chromatographic properties on different stationary phases and the influence of the methanol content in the carbon dioxide mobile phase. The separation of the metal compounds was conducted with and without solvent injection. A calibration curve was obtained for uranium in the range of 52-323 ng injected. The accuracy of the method is 0.5%, the repeatability 4%. The same studies were performed with a new compound, diacetyl-2,6 pyridine bis(4-tert-butyl benzoylhydrazone). An increase in retention and efficiency was then observed. 30 refs., 5 figs., 3 tabs.

  4. COED Transactions, Vol. X, No. 5, May 1978. STAGEF, A Program to Compute the Internal Variables of an Operating Distillation Column.

    ERIC Educational Resources Information Center

    Marcovitz, Alan B., Ed.

    A digital computer program, STAGEF, designed for use with the distillation experiments in a typical undergraduate Chemical Engineering laboratory in Unit Operations is explained. The program enables the student to determine the rate of liquid overflow and vapor boil-up which leaves each tray within the distillation column. The student may also

  5. COED Transactions, Vol. X, No. 5, May 1978. STAGEF, A Program to Compute the Internal Variables of an Operating Distillation Column.

    ERIC Educational Resources Information Center

    Marcovitz, Alan B., Ed.

    A digital computer program, STAGEF, designed for use with the distillation experiments in a typical undergraduate Chemical Engineering laboratory in Unit Operations is explained. The program enables the student to determine the rate of liquid overflow and vapor boil-up which leaves each tray within the distillation column. The student may also…

  6. Forensic analysis of 10 barbiturates in human biological samples using a new reversed-phase chromatographic column packed with 2-micrometre porous microspherical silica-gel.

    PubMed

    Tanaka, E; Terada, M; Tanno, K; Misawa, S; Wakasugi, C

    1997-02-01

    A high-performance liquid chromatographic method has been developed for the forensic analysis of 10 frequently used barbiturates (BARs) (allobarbital, amobarbital, barbital, cyclobarbital, hexobarbital, metharbital, pentobarbital, phenobarbital, secobarbital and thiopental) using a recently developed reversed-phase column packed with 2-micron particles. The results show that the new ODS column packing gives higher sensitivity and a shorter analysis time than the conventional ODS column packing when applied to the analysis of biological samples. PMID:9050222

  7. Validating the Equilibrium Stage Model for an Azeotropic System in a Laboratorial Distillation Column

    ERIC Educational Resources Information Center

    Duarte, B. P. M.; Coelho Pinheiro, M. N.; Silva, D. C. M.; Moura, M. J.

    2006-01-01

    The experiment described is an excellent opportunity to apply theoretical concepts of distillation, thermodynamics of mixtures and process simulation at laboratory scale, and simultaneously enhance the ability of students to operate, control and monitor complex units.

  8. Intrinsic advantages of packed capillaries over narrow-bore columns in very high-pressure gradient liquid chromatography.

    PubMed

    Gritti, Fabrice; McDonald, Thomas; Gilar, Martin

    2016-06-17

    250μm×100mm fused silica glass capillaries were packed with 1.8μm high-strength silica (HSS) fully porous particles. They were prepared without bulky stainless steel endfittings and metal frits, which both generate significant sample dispersion. The isocratic efficiencies and gradient peak capacities of these prototype capillary columns were measured for small molecules (n-alkanophenones) using a home-made ultra-low dispersive micro-HPLC instrument. Their resolution power was compared to that of standard 2.1mm×100mm very high-pressure liquid chromatography (vHPLC) narrow-bore columns packed with the same particles. The results show that, for the same column efficiency (25000 plates) and gradient steepness (0.04min(-1)), the peak capacity of the 250μm i.d. capillary columns is systematically 15-20% higher than that of the 2.1mm i.d. narrow-bore columns. A validated model of gradient chromatography enabled one to predict accurately the observed peak capacities of the capillary columns for non-linear solvation strength retention behavior and under isothermal conditions. Thermodynamics applied to the eluent quantified the temperature difference for the thermal gradients in both capillary and narrow-bore columns. Experimental data revealed that the gradient peak capacity is more affected by viscous heating than the column efficiency. Unlike across 2.1mm i.d. columns, the changes in eluent composition across the 250μm i.d. columns during the gradient is rapidly relaxed by transverse dispersion. The combination of (1) the absence of viscous heating and (2) the high uniformity of the eluent composition across the diameter of capillary columns explains the intrinsic advantage of capillary over narrow-bore columns in gradient vHPLC. PMID:27185055

  9. 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 ...

  10. An applicable method for efficiency estimation of operating tray distillation columns and its comparison with the methods utilized in HYSYS and Aspen Plus

    NASA Astrophysics Data System (ADS)

    Sadeghifar, Hamidreza

    2015-10-01

    Developing general methods that rely on column data for the efficiency estimation of operating (existing) distillation columns has been overlooked in the literature. Most of the available methods are based on empirical mass transfer and hydraulic relations correlated to laboratory data. Therefore, these methods may not be sufficiently accurate when applied to industrial columns. In this paper, an applicable and accurate method was developed for the efficiency estimation of distillation columns filled with trays. This method can calculate efficiency as well as mass and heat transfer coefficients without using any empirical mass transfer or hydraulic correlations and without the need to estimate operational or hydraulic parameters of the column. E.g., the method does not need to estimate tray interfacial area, which can be its most important advantage over all the available methods. The method can be used for the efficiency prediction of any trays in distillation columns. For the efficiency calculation, the method employs the column data and uses the true rates of the mass and heat transfers occurring inside the operating column. It is highly emphasized that estimating efficiency of an operating column has to be distinguished from that of a column being designed.

  11. Fast and Universal HPLC Method for Determination of Permethrin in Formulations Using 1.8-µm Particle-Packed Column and Performance Comparison with Other Column Types

    PubMed Central

    Shishovska, Maja A.; Stefova, Marina T.

    2012-01-01

    An HPLC method has been developed for the fast separation and quantification of permethrin using C18 column packed with 1.8 µm particles. The method is specific with good resolution to degradation products and to other present components. It has acceptable validation results. The run time is 4.5 min (or may be within 1.6 min is rapid resolution mode) with an organic solvent consumption of 3.6 mL per run. The method has been applied to samples of formulations for various uses: mattress cleaner, shampoo, and veterinary powder. The performance of the applied column is compared with other common column types. The relationships between linear velocity of the mobile phase (u) and resolution factor (Rs), back-pressure (ΔP), and efficiency (H) are presented. The experimental data shows the advantages of 1.8-µm particle columns to be a significant reduction in solvent consumption (by factor of 4.4 and 1.5) and a reduction in run-time (by factor 4.7 and 1.5), and the weaknesses are a high back-pressure and lower efficiency. Finally, it has been shown that use of 1.8-µm particle packed columns with conventional HPLC systems is possible, but with limitations in mobile phase flow-rate. PMID:22291055

  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. Simultaneous determination of alcohols and ethylene glycol in serum by packed- or capillary-column gas chromatography.

    PubMed

    Livesey, J F; Perkins, S L; Tokessy, N E; Maddock, M J

    1995-02-01

    We developed a packed-column chromatographic procedure capable of simultaneous quantitation of methanol, ethanol, isopropanol, acetone, and ethylene glycol. This method was then updated to a rapid, sensitive, wide-bore capillary method. The packed-column system uses direct injection of 1 microL of Na2WO4/H2SO4-deproteinized serum onto a 1.8 m x 2 mm (i.d.) column packed with 80/100 HayeSep R. A linear temperature gradient from 90 to 205 degrees C allows complete elution of all components within 20 min; minimum detection limits are 2 mmol/L. The wide-bore capillary method uses 0.1 microL of sample deproteinized by ultrafiltration, injected onto a 30 m x 0.53 mm (i.d.) 3-microns Rtx-200 (Restek) column. Baseline resolution to a minimum detection limit of 0.1 mmol/L of all compounds is achieved in 5 min with a linear temperature gradient from 40 to 250 degrees C and dual internal standards of n-propanol and 1,2-butanediol. PMID:7874784

  15. Fabrication of two-weir structure-based packed columns for on-chip solid-phase extraction of DNA.

    PubMed

    Zhong, Runtao; Liu, Dayu; Yu, Linfen; Ye, Nannan; Dai, Zhongpeng; Qin, Jianhua; Lin, Bingcheng

    2007-08-01

    Microchip-based packed column SPE of DNA was performed using the microfabricated two-weir structure within a microchannel. We developed two methods to fabricate the two-weir structured glass chips: a "two-side etching/alignment" method and a simplified "one-side/two-step etching" method. The former method required a straightforward alignment step, while the latter approach comprised a simplified wet etching process using paraffin wax as the temporary protective layer. Both methods were convenient and rapid as compared to the previous approaches. Through a reversibly sealed bead-introduction channel, beads can be fed into or out of the chip columns, thus enabling refreshment of the packing materials. Using the proposed chip columns, highly efficient lambda-DNA extractions (average recovery >80%) were performed with good chip-to-chip reproducibility (RSD <10%). The on-chip SPE procedure was completed within 15 min at the flow rate of 3 microL/min and the bulk of the loaded DNA was eluted within a small volume of approximately 8 microL. Application of the microchip-based packed columns was demonstrated by purifying PCR-amplifiable genomic DNA from human hepatocellular carcinoma (HepG2) cells and human whole blood samples. PMID:17640088

  16. Capillary columns with in situ formed porous monolithic packing for micro high-performance liquid chromatography and capillary electrochromatography.

    PubMed

    Gusev, I; Huang, X; Horváth, C

    1999-09-01

    Capillary columns with monolithic stationary phase were prepared from silanized fused-silica capillaries of 75 microns I.D. by in situ copolymerization of divinylbenzene either with styrene or vinylbenzyl chloride in the presence of a suitable porogen. The porous monolithic support in this study was used either directly or upon functionalization of the surface to obtain a stationary phase that was appropriate for the separation of peptides by capillary electrochromatography (CEC). The main advantages of monolithic columns are as follows. They do not need retaining frits, they do not have charged particles that can get dislodged in high electric field, and they have relatively high permeability and stability. Whereas such columns are designed especially for CEC, they find application in micro high-performance liquid chromatography (mu-HPLC) as well. Five different porogens were employed to prepare the monolithic columns that were examined for permeability and porosity. The flexibility of fused-silica capillaries was not adversely affected by the monolithic packing and the longevity of the columns was satisfactory. This may also be due to the polymerization technique, which resulted in a fluid-impervious outer layer of the monolith that precluded contact between the fused-silica surface and the liquid mobile phase. For the most promising columns, the conductivity ratios and the parameters of the simplified van Deemter equation, both in mu-HPLC and CEC, were evaluated. It was found that the efficiency of the monolithic columns in CEC was significantly higher than in mu-HPLC in the same way as observed with capillary columns having conventional particulate packing. This is attributed to the relaxation of band-broadening with electroosmotic flow (EOF) with respect to that with viscous flow. It follows then that the requirement of high packing uniformity to obtain high efficiency may also be relaxed in CEC. Angiotensin-type peptides were separated by CEC with columns packed with a monolithic stationary phase having fixed n-octyl chains and quaternary ammonium groups at the surface. Plate heights of about 8 microns were routinely obtained. The mechanism of the separation is based on the interplay between EOF, chromatographic retention and electrophoretic migration of the positively charged peptides. The results of the complex migration process, with highly nonlinear dependence of the migration times on the organic modifier and the salt concentration, cannot be interpreted within the framework of classical chromatography or electrophoresis. PMID:10514993

  17. Performance limits of monolithic and packed capillary columns in high-performance liquid chromatography and capillary electrochromatography.

    PubMed

    Eeltink, Sebastiaan; Desmet, Gert; Vivó-Truyols, Gabriel; Rozing, Gerard P; Schoenmakers, Peter J; Kok, Wim Th

    2006-02-01

    A method is proposed for the comprehensive characterization and comparison of columns in the high-performance liquid chromatographic (HPLC) and capillary electrochromatographic (CEC) modes. Using this approach, column parameters such as the number of plates, the eddy-diffusion and mass-transfer contributions to peak broadening, the permeability, and the analysis time are incorporated in a single graph and a comparison in terms of efficiency and speed is obtained. The chromatographic performance of silica-based and polymer-based monolithic capillary columns is discussed and a comparison is made with the performance of packed columns. Also, the potential of ultra-high-pressure liquid chromatography is discussed in this context. In the HPLC mode, the best results were obtained with silica monoliths; in the CEC mode, the low-density methacrylate-ester-based monoliths showed the best performance. PMID:16364339

  18. Mobility of Dissolved Organic Matter from the Suwannee River (Georgia, USA) in Sand-Packed Columns

    PubMed Central

    McInnis, Daniel P.; Bolster, Diogo; Maurice, Patricia A.

    2015-01-01

    Abstract Transport of dissolved organic matter (DOM) from the Suwannee River and of synthetic polystyrene sulfonates (PSSs) was investigated in columns packed with naturally Fe/Al-oxide-coated sands from Oyster, Virginia. Surface-water samples were collected in May 2012 and processed by XAD-8 (humic substances; HPOA), XAD-4 (transphilic acids [TPIAs]), and reverse osmosis (broad range of components; NOM). Median transport time (Ro) of PSSs increased with molecular weight (MW) from 1,000 to 8,000 Da but decreased for the largest PSS (18,000 Da), which is consistent with previous observations of MW effects on DOM adsorption and transport. Breakthrough curves (BTCs) of HPOAs and NOM were similar whereas TPIA transport was distinct; although all DOM samples had similar Ro values, BTC asymmetry and dispersivity were greater for TPIAs. All samples exhibited power-law tailing that is characteristic of heterogeneous sorbent/sorbate interactions, potentially including kinetic effects. The one-dimensional advection-dispersion equation was unable to capture the tailing but it was captured well using a continuous-time random walk (CTRW) model. CTRW parameters were similar for the NOM and HPOA samples but distinctly different for TPIAs, which had more pronounced tailing. While retardation of organics generally tends to increase with MW, the lower average MW of TPIAs did not result in decreased overall retardation, which suggests the importance of compositional differences. Results suggest that while TPIAs tend to be a relatively minor component of DOM, their transport behavior differs from that of the predominant HPOA fraction, and they might thus have different impacts on pollutant transport. PMID:25565760

  19. Removal of pollutant compounds from water supplies using ozone, ultraviolet light, and a counter, current packed column. Master's thesis

    SciTech Connect

    Kelly, E.L.

    1991-01-01

    Many water pollutants are determined to be carcinogenic and often appear in very low concentrations and still pose a health risk. Conventional water treatment processes cannot remove these contaminants and there is a great demand for the development of alternative removal technologies. The use of ozone and ultraviolet light in a counter current packed column could prove to be an effective treatment process to remove these contaminants.

  20. Two-Phase Flow in Packed Columns and Generation of Bubbly Suspensions for Chemical Processing in Space

    NASA Technical Reports Server (NTRS)

    Motil, Brian J.; Green, R. D.; Nahra, H. K.; Sridhar, K. R.

    2000-01-01

    For long-duration space missions, the life support and In-Situ Resource Utilization (ISRU) systems necessary to lower the mass and volume of consumables carried from Earth will require more sophisticated chemical processing technologies involving gas-liquid two-phase flows. This paper discusses some preliminary two-phase flow work in packed columns and generation of bubbly suspensions, two types of flow systems that can exist in a number of chemical processing devices. The experimental hardware for a co-current flow, packed column operated in two ground-based low gravity facilities (two-second drop tower and KC- 135 low-gravity aircraft) is described. The preliminary results of this experimental work are discussed. The flow regimes observed and the conditions under which these flow regimes occur are compared with the available co-current packed column experimental work performed in normal gravity. For bubbly suspensions, the experimental hardware for generation of uniformly sized bubbles in Couette flow in microgravity conditions is described. Experimental work was performed on a number of bubbler designs, and the capillary bubble tube was found to produce the most consistent size bubbles. Low air flow rates and low Couette flow produce consistent 2-3 mm bubbles, the size of interest for the "Behavior of Rapidly Sheared Bubbly Suspension" flight experiment. Finally the mass transfer implications of these two-phase flows is qualitatively discussed.

  1. Modification of cleanup methods for dioxin analysis in green leafy vegetables and comparison of packing methods for a multi-layer silica gel column.

    PubMed

    Amakura, Yoshiaki; Tsutsumi, Tomoaki; Sasaki, Kumiko; Maitani, Tamio

    2003-12-01

    To determine polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (Co-PCBs) in green leafy vegetables, the cleanup method was modified, and packing methods for a multi-layer silica gel column were compared in food samples. First, the additional cleanup was examined for a mono-ortho PCBs fraction obtained by alumina column chromatography from spinach extract. Small solids such as rough crystals that remained after concentration of the mono-ortho PCBs fraction were identified as long-chain hydrocarbons from leaf epicuticular wax by GC/MS. Cleanup using an activated carbon silica gel column with n-hexane as the washing solvent was effective. Next, multi-layer silica gel columns packed by wet packing and dry packing were compared using komatsuna, salmon and butter as samples. The columns prepared by both methods gave similar values at each isomeric concentration level and showed similar efficiency with favorable recoveries. PMID:15038115

  2. Design of a selftuning fuzzy control system and the application to a distillation column

    SciTech Connect

    Hanakuma, Y.; Irizuki, Y; Adachi, M. . Technical and Engineering Dept.); Nakanishi, E. . Dept. of Chemical Engineering)

    1994-01-01

    A selftuning fuzzy control system was developed for industrial use, with a hierarchical structure of, in the lower loop, an algorithm for feedforward-feedback fuzzy control and, in the upper loop, a learning algorithm for evaluation of the control performance and selftuning of the gain of the feedforward fuzzy control. The function of the selftuning fuzzy controller is to overadjust the gain of the feedback fuzzy controller, using a learning rule which compares the trends in the manipulated variables from the feedforward and feedback controllers. This fuzzy control system was tested in a demethanizer column in an ethylene plant, and was effective for the bottom-temperature control loop, which has, hitherto, been difficult to control.

  3. Particle-packed column versus silica-based monolithic column for liquid chromatography-electrospray-linear ion trap-tandem mass spectrometry multiallergen trace analysis in foods.

    PubMed

    Bignardi, Chiara; Elviri, Lisa; Penna, Andrea; Careri, Maria; Mangia, Alessandro

    2010-11-26

    A bicarbonate buffer-based extraction method for the simultaneous analysis of five nut allergens (Ana o 2, cashew-nut; Cor a 9, hazelnut; Pru 1, almond; Ara h3/4, peanut; Jug r 4, walnut) in cereals and biscuits using liquid chromatography-electrospray-linear ion trap-tandem mass spectrometry (LC-ESI-LIT-MS(2)) was developed and validated. The method was based on our earlier published LC-MS(2)-based method in a research frame aimed at the identification and determination of hidden allergens in foods by using selective biomarker peptides. A C18 particle-packed column and a silica-based C18 monolithic column were compared in terms of chromatographic performances, such as peak shape, resolution, analysis time and selectivity. The C18 particle-packed column exhibited better performances and was further used for method development and validation. By operating under MS(2) selected reaction monitoring (SRM) acquisition mode, linearity, limits of detection (LOD) and quantitation, trueness and precision were evaluated on breakfast samples enriched with a mix of the five nuts. Good linearity of the matrix matched-calibration curves was obtained and detection limit values generally varied from 14 to 55 mg nut/kg matrix. Recoveries were in the 76±4% to 94±3% range with RSD <15%. The capabilities of LIT to perform MS(n) fragmentation was exploited to improve selectivity of the analysis, and the LC-(SRM) MS(2) method was compared in terms of LOD, linearity, precision and accuracy with a LC-(SRM) MS(3) method. Finally, both the LC-MS(2) and LC-MS(3) methods were successfully applied to the analysis of nut traces in commercially available breakfast cereals and biscuits. PMID:21030028

  4. Reaction of trace mercury in natural gas with dilute polysulfide solutions in a packed column

    SciTech Connect

    Not Available

    1991-12-01

    This paper reports that the natural gas produced around the world can contain traces of mercury which have to be removed. It is difficult to purify gas to desired mercury levels using conventional techniques. By scrubbing with dilute polysulfide solution, the residual mercury in the gas can be removed from about 0.1 to below 0.01 ppb, a reduction of 90%. In this system, the gas is passed through a packed tower wetted with a solution containing 3 ppm of polysulfide salt. Stainless steel packings are effective for this application. In addition to promoting gas-liquid contact, the stainless steel packings adsorb and concentrate polysulfides which react with Hg in the gas to form insoluble HgS, and thus remove Hg from the gas.

  5. Chromatographic behaviour and comparison of column packed with sub-2 microm stationary phases in liquid chromatography.

    PubMed

    Nguyen, Dao T-T; Guillarme, Davy; Rudaz, Serge; Veuthey, Jean-Luc

    2006-09-22

    In order to reduce the analysis time and maintain good efficiency in liquid chromatography, it is advisable to simultaneously decrease the column length and the particle size of the chromatographic support. Therefore, several manufacturers have developed and commercialized short columns filled with particles that have a diameter smaller than 2 microm. The focus of this work was to check the chromatographic performance of such columns and compare possibilities offered by sub-2 microm supports with conventional columns in terms of analysis time reduction and efficiency improvements. For this purpose, different parameters were discussed namely: separation impedance (E), Knox curves (h,v), and number of plates by time unit (N/t0). Kinetic plots were also drawn. It appeared that sub-2 microm supports were well adapted to improve chromatographic performance and to reduce the analysis time. Furthermore, it was also demonstrated that the best chromatographic performances were reached with high pressure systems (up to 1000 bar). PMID:16846612

  6. Catalytic distillation structure

    DOEpatents

    Smith, Jr., Lawrence A.

    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.

  7. Separative analyses of a chromatographic column packed with a core-shell adsorbent for lithium isotope separation

    SciTech Connect

    Sugiyama, T.; Sugura, K.; Enokida, Y.; Yamamoto, I.

    2015-03-15

    Lithium-6 is used as a blanket material for sufficient tritium production in DT fueled fusion reactors. A core-shell type adsorbent was proposed for lithium isotope separation by chromatography. The mass transfer model in a chromatographic column consisted of 4 steps, such as convection and dispersion in the column, transfer through liquid films, intra-particle diffusion and and adsorption or desorption at the local adsorption sites. A model was developed and concentration profiles and time variation in the column were numerically simulated. It became clear that core-shell type adsorbents with thin porous shell were saturated rapidly relatively to fully porous one and established a sharp edge of adsorption band. This is very important feature because lithium isotope separation requires long-distance development of adsorption band. The values of HETP (Height Equivalent of a Theoretical Plate) for core-shell adsorbent packed column were estimated by statistical moments of the step response curve. The value of HETP decreased with the thickness of the porous shell. A core-shell type adsorbent is, then, useful for lithium isotope separation. (authors)

  8. Separation of oxidatively damaged DNA nucleobases and nucleosides on packed and monolith C18 columns by HPLC-UV-EC.

    PubMed

    Kelly, Michele C; White, Blánaid; Smyth, Malcolm R

    2008-02-15

    This study involves the incorporation of a commercially available Phenomenex Onyx C18 monolith column into the separation and detection of oxidative DNA damage. It includes thorough investigation of monolith performance and a comparison of the performance of monolith columns with a commercially available packed Restek reverse phase Ultra C18 column for the separation of DNA bases and nucleosides. The performance of the monolith was examined using efficiency, resolution, plate height, asymmetry and retention times, and each case showed improved or at least comparable results in the separation of a mix of DNA bases and nucleosides. A 90% reduction, from just under 40min to just under 4min, was obtained in the elution time of this separation. To the best of our knowledge, this is the first report of a fast monolith column separation successfully coupled to both a UV-vis and EC detector, which is especially useful for the analysis of oxidative DNA damage. The determination of 8-oxoG and 8-OH-dG, oxidation products of guanine and 2'-deoxyguanosine, respectively, may be compromised by their ease of oxidation and therefore the fast separation, selective and sensitive detection, with no artifactual oxidation, detailed in this report, is ideal. PMID:18243824

  9. 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.

  10. A simplified mathematical model of the cryogenic distillation with application to the (13C) isotope separation column

    NASA Astrophysics Data System (ADS)

    Neaga, A. O.; Festila, C.; Dulf, E. H.; Both, R.; Szelitzky, T.; Gligan, M.

    2012-02-01

    The isotope (13C) has a widespread application in many fields such as chemistry, physics, medicine, etc. To obtain a high concentration in isotope of interest, in our case (13C), it is used the method of cryogenic distillation of carbon monoxide (CO) which is based on the difference between the vapor pressure of (12C16O) and (13C16O) at the temperature of liquid nitrogen. Isotopic separation plant, used to obtain the isotope (13C), is a complex installation, with many inputs and outputs, rather difficult to control. Due to this reason, from the point of view of automation, it is needed a simplified mathematical model. This model can be determined only with some presumption and simplification assumptions. Using the physical laws, the hydrodynamic part of the process and the mass balance will be described by partial differential equations. In order to design a controller for the column, it is needed a transfer function or a statespace realization of the plant, which is the main contribution of the present work. Implementing this mathematical model will be the key element for describing and understanding the operation of the plant and for future development of process control strategies.

  11. Physical properties and structure of fine core-shell particles used as packing materials for chromatography relationships between particle characteristics and column performance

    SciTech Connect

    Gritti, Fabrice; Guiochon, Georges A

    2010-01-01

    The recent development of new brands of packing materials made of fine porous-shell particles, e.g., Halo and Kinetex, has brought great improvements in potential column efficiency, demanding considerable progress in the design of chromatographic instruments. Columns packed with Halo and Kinetex particles provide minimum values of their reduced plate heights of nearly 1.5 and 1.2, respectively. These packing materials have physical properties that set them apart from conventional porous particles. The kinetic performance of 4.6 mm I.D. columns packed with these two new materials is analyzed based on the results of a series of nine independent and complementary experiments: low-temperature nitrogen adsorption (LTNA), scanning electron microscopy (SEM), inverse size-exclusion chromatography (ISEC), Coulter counter particle size distributions, pycnometry, height equivalent to a theoretical plate (HETP), peak parking method (PP), total pore blocking method (TPB), and local electrochemical detection across the column exit section (LED). The results of this work establish links between the physical properties of these superficially porous particles and the excellent kinetic performance of columns packed with them. It clarifies the fundamental origin of the difference in the chromatographic performances of the Halo and the Kinetex columns.

  12. Transverse bacterial migration induced by chemotaxis in a packed column with structured physical heterogeneity

    PubMed Central

    Wang, Meng; Ford, Roseanne M.

    2009-01-01

    The significance of chemotaxis in directing bacterial migration towards contaminants in natural porous media was investigated under groundwater flow conditions. A laboratory-scale column, with a coarse-grained sand core surrounded by a fine-grained annulus, was used to simulate natural aquifers with strata of different hydraulic conductivities. A chemoattractant source was placed along the central axis of the column to model contaminants trapped in the heterogeneous subsurface. Chemotactic bacterial strains, Escherichia coli HCB1 and Pseudomonas putida F1, introduced into the column by a pulse injection, were found to alter their transport behaviors under the influence of the attractant chemical emanating from the central source. For E. coli HCB1, approximately 18% more of the total population relative to the control without attractant exited the column from the coarse sand layer due to the chemotactic effects of α-methylaspartate under an average fluid velocity of 5.1 m/d. Although P. putida F1 demonstrated no observable changes in migration pathways with the model contaminant acetate under the same flow rate, when the flow rate was reduced to 1.9 m/d, approximately 6~10% of the population relative to the control migrated from the fine sand layer towards attractant into the coarse sand layer. Microbial transport properties were further quantified by a mathematical model to examine the significance of bacterial motility and chemotaxis under different hydrodynamic conditions, which suggested important considerations for strain selection and practical operation of bioremediation schemes. PMID:19731698

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

    SciTech Connect

    Kirkland, J.J.

    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.

  14. Extraction of squalene from shark liver oil in a packed column using supercritical carbon dioxide

    SciTech Connect

    Catchpole, O.J.; Kamp, J.C. von; Grey, J.B.

    1997-10-01

    Continuous extraction of squalene from shark liver oil using supercritical carbon dioxide was carried out in both laboratory and pilot scale plant. The shark liver oil contained around 50% by weight squalene, which was recovered as the main extract stream. The other major components in the oil were triglycerides, which were recovered as raffinate, and pristane, which was recovered as a second extract stream. Separation performance was determined as a function of temperature; pressure; oil to carbon dioxide flow rate ratio, packed height and type of packing; and reflux ratio. The pressure, temperature, and feed oil concentration of squalene determined the maximum loading of oil in carbon dioxide. The oil to carbon dioxide ratio determined the squalene concentration in both the product stream and raffinate stream. The ratio of oil flow rate to the flow rate of squalene required to just saturate carbon dioxide was found to be a useful correlating parameter for the oil loadings and product compositions. Of the three packings investigated, wire wool gave the best separation efficiency and Raschig rings the worst efficiency. Mass transfer correlations from the literature were used to estimate the number of transfer units (NTU) from experimental data and literature correlations. NTU`s from the experimental data were comparable to predictions at a pilot scale but were underpredicted at the laboratory scale. The use of reflux at the pilot scale enabled the concentration of squalene in the product stream to be increased from 92% by mass to a maximum of 99% by mass at fractionation conditions of 250 bar and 333 K.

  15. Transport and retention of high concentrated nano-Fe/Cu particles through highly flow-rated packed sand column.

    PubMed

    Hosseini, Seiyed Mossa; Tosco, Tiziana

    2013-01-01

    The design of an efficient field-scale remediation based on the use of nanoscale zero valent iron (NZVI) requires an accurate assessment of the mobility of such particles in saturated porous media, both during injection in the subsurface (short-term mobility) and later (long-term mobility). In this study, the mobility of highly concentrated dispersions of bimetallic Fe/Cu nanoparticles (d(50) = 70 5 nm) in sand-packed columns (0.5 m length and 0.025 m inner diameter) was studied. In particular, the influence of flow rate (V = 5 10(-4), 1 10(-3), 2 10(-3) m/s) and injected particle concentrations (2, 5, 8, 12 g/l) was addressed. Breakthrough curves and water pressure drop along the column, averaged effective porosity and final distribution of retained particles along the column were measured. Experimental results evidenced a good mobility of the Fe/Cu particles, with significant breakthrough in all explored experimental conditions of flow rate and C(0), without requiring the addition of any stabilizing agent. Clogging phenomenon of the column and also the pore pressure variation during injection period are strongly affected by injected concentration. Clogging due to deposition of particles following a ripening dynamics was observed in particular for C(0) = 8 and 12 g/l. The experimental data were modeled using the E-MNM1D software. The study has implications for field injection of bimetallic nanoparticles, suggesting that particular care is to be devoted when selecting injection concentration, to avoid porous medium clogging and control the radius of influence. PMID:23141767

  16. Modern analytical supercritical fluid chromatography using columns packed with sub-2 μm particles: a tutorial.

    PubMed

    Nováková, Lucie; Perrenoud, Alexandre Grand-Guillaume; Francois, Isabelle; West, Caroline; Lesellier, Eric; Guillarme, Davy

    2014-05-01

    This tutorial provides an overview of the possibilities, limitations and analytical conditions of modern analytical supercritical fluid chromatography (SFC) using columns packed with sub-2 μm particles. In particular, it gives a detailed overview of commercially available modern SFC instrumentation and the detectors that can be employed (UV, MS, ELSD, FID, etc.). Some advice on the choice of the stationary phase dimensions and chemistries, the nature of the mobile phase (choice of organic modifier and additives) and its flow rate as well as the backpressure and temperature are also provided. Finally, several groups of potentially problematic compounds, including lipophilic compounds, hydrophilic substances and basic drugs, are discussed in detail. All these families of analytes can be resolved with SFC but require specific analytical conditions. PMID:24759745

  17. Organic manure and urea effect on metolachlor transport through packed soil columns.

    PubMed

    Singh, Neera

    2003-01-01

    Application of organic manure (OM) amendments and nitrogen fertilizers can affect the sorption and movement of pesticides in soil. This study summarizes the sorption and leaching of metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylphenyl) acetamide] in soils after cow (Bos taurus) manure (2.5 and 5.0%) and urea (60 and 120 kg N ha(-1)) amendments in batch and column experiments. Both cow manure and urea applications increased metolachlor sorption in soils. The values of the Freundlich adsorption parameter K(r)(1/n) for treatments T0, T1 (OM), and T2 (OM) were 2.31, 3.32, and 3.96 in Soil 1; 2.02, 2.77, and 3.32 in Soil 2; and 1.10, 1.46, and 2.02 in Soil 3, respectively. Similarly, K(f)(1/n) values for treatment T1 (urea) and T2 (urea) were 2.37 and 2.84 in Soil 1; 2.16 and 2.83 in Soil 2; and 1.50 and 1.70 in Soil 3, respectively. Column leaching studies using Soil 1 indicated that OM application drastically reduced the metolachlor leaching losses from 50% (natural soil) to < 1.0% (5.0% OM amendment). Likewise, urea application also decreased metolachlor mobility and leaching losses in columns treated with 60 and 120 kg N ha(-1) urea were 33 and 20%, respectively. The reduction in the metolachlor leaching losses was achieved through the increase in the sorption capability of the OM- and urea-amended soil. Therefore, coapplication of metolachlor with cow manure or urea fertilizers will not enhance metolachlor mobility and reduces metolachlor leaching losses in low-organic-matter soil. PMID:14535316

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

    PubMed

    Syngouna, Vasiliki I; Chrysikopoulos, Constantinos V

    2016-03-01

    The cotransport of clay colloids and viruses in vertically oriented laboratory columns packed with glass beads was investigated. Bacteriophages MS2 and ΦX174 were used as model viruses, and kaolinite (ΚGa-1b) and montmorillonite (STx-1b) as model clay colloids. A steady flow rate of Q=1.5mL/min was applied in both vertical up (VU) and vertical down (VD) flow directions. In the presence of KGa-1b, estimated mass recovery values for both viruses were higher for VD than VU flow direction, while in the presence of STx-1b the opposite was observed. However, for all cases examined, the produced mass of viruses attached onto suspended clay particles were higher for VD than VU flow direction, suggesting that the flow direction significantly influences virus attachment onto clays, as well as packed column retention of viruses attached onto suspended clays. KGa-1b hindered the transport of ΦX174 under VD flow, while STx-1b facilitated the transport of ΦX174 under both VU and VD flow directions. Moreover, KGa-1b and STx-1b facilitated the transport of MS2 in most of the cases examined except of the case where KGa-1b was present under VD flow. Also, the experimental data were used for the estimation of virus surface-coverages and virus surface concentrations generated by virus diffusion-limited attachment, as well as virus attachment due to sedimentation. Both sedimentation and diffusion limited virus attachment were higher for VD than VU flow, except the case of MS2 and STx-1b cotransport. The diffusion-limited attachment was higher for MS2 than ΦΧ174 for all cases examined. PMID:26747984

  19. 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).

  20. Preparation and application of an immunoaffinity column based on an antibody with strong affinity and packing material with good stability.

    PubMed

    Zhang, Hongyan; Wang, Mengmeng; Wang, Yao; Li, Qingling; Zhou, Jianhua; Huo, Feng; Tang, Bo

    2013-01-01

    This article describes the production of an anti-citrinin antibody that showed a high affinity constant (Ka) of 6.28 × 10⁹ and good tolerance to organic solvent and low pH, the synthesis of a Cu (II)-embedded polymer that showed strong binding with this antibody and the preparation of packing material for an immunoaffinity column (IAC) that show good stability. Most of the IACs reported either use harsh elution conditions and are used only once or use gentle elution conditions and are reused many times. Here, through the combined use of a strong-affinity antibody and packing material with good stability, high recoveries during clean-up and yet simultaneously good stability of the IAC were successfully achieved. Under optimised conditions of 80% methanol (pH 3), the IACs were used to clean-up the extracts of Monascus colour and red yeast rice samples, followed by HPLC detection. The recoveries of citrinin from spiked samples at levels of 50-200 μg kg⁻¹ were in the range of 84-97%. PMID:23710628

  1. Comparison of simulated distillation to true boiling point distillation of H-Coal distillates

    SciTech Connect

    Kiser, M.D.; Malone, D.P.

    1982-01-01

    A comparison of simulated distillation to true boiling point (TBP) from both actual TBP distillation and single theoretical plate distillations converted to TBP for various H-Coal distillates is presented. The TBP distillation data was obtained using a Todd distillation column having 15 theoretical plates and a 5:1 reflux ratio. The simulated data presented were obtained using a Hewlitt Packard 5731 gas chromatograph equipped with dual flame ionization detectors. Graphical comparisons of distillation curves obtained by direct weight % TBP distillation and simulated distillation for a full range H-Coal syncrude, of boiling point curves for H-Coal naphtha, H-Coal middle distillate, and H-Coal heavy distillate are included. From an examination of the distillation data, it was apparent that simulated distillation data compared favorable with weight % distillation data, whether derived from direct TBP distillation or single theoretical plate distillation data and converted to TBP data. (BLM)

  2. Adsorption performance of packed bed column for nitrate removal using PAN-oxime-nano Fe2O3.

    PubMed

    Jahangiri-Rad, Mahsa; Jamshidi, Arsalan; Rafiee, Mohammad; Nabizadeh, Ramin

    2014-01-01

    A continuous fixed bed study was carried out by using PAN-oxime-nano Fe2O3 as a sorbent for the removal of nitrate from aqueous solution. The effect of factors, such as flow rate (2, 5 and 7 mL/min) and bed depth (5, 10 and 15 cm) were studied. Data confirmed that the breakthrough curves were dependent on flow rate and bed depth. The adsoption capacities observed in diffent conditions of flow rates (2,5 and 7 mL/min) were 11.65, 24.38 and 25.89, respectively. Thomas model was applied to experimental data to predict the breakthrough curves using linear regression and to determine the characteristic parameters of the packed bed column. Bed depth/service time analysis (BDST) model was used to investigate the effect of bed depth on breakthrough curves. The results showed that Thomas model was suitable for the normal description of breakthrough curve at the experimental condition. The data were in good agreement with BDST model with R(2) > 0.98. Statistical analyses were performed on fluoride removal obtained from different flow rates using SPSS16 software by applying Kruskal- Wallis test. These findings suggested that PAN-oxime-nano Fe2O3 in the column structure presents a great potential in removal of nitrate from aqueous solutions. PMID:25045525

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

    PubMed

    Sarkar, Priyabrata; Pal, Priyabrata; Bhattacharyay, Dipankar; Banerjee, Suchanda

    2010-11-01

    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 these beads to generate isotherm data. The loading capacity was found to be 3.8 mg arsenic/gm of adsorbent. The experimental data conformed to Freundlich adsorption isotherm. A generalized mathematical model was also developed and the visual basic codes run with the physical parameters of the adsorbent and isotherm data that were evaluated experimentally was achieved for a continuous 75 days' operation. The safe disposal of the spent adsorbent was confirmed by the toxicity characteristic leaching procedure (TCLP) results. With known set of physical parameters of the adsorbent, input water flow rate and its arsenic concentration, the model could predict the number of days the column would run with output below a specific arsenic concentration. PMID:20924920

  4. Adsorption performance of packed bed column for nitrate removal using PAN-oxime-nano Fe2O3

    PubMed Central

    2014-01-01

    A continuous fixed bed study was carried out by using PAN-oxime-nano Fe2O3 as a sorbent for the removal of nitrate from aqueous solution. The effect of factors, such as flow rate (2, 5 and 7 mL/min) and bed depth (5, 10 and 15 cm) were studied. Data confirmed that the breakthrough curves were dependent on flow rate and bed depth. The adsoption capacities observed in diffent conditions of flow rates (2,5 and 7 mL/min) were 11.65, 24.38 and 25.89, respectively. Thomas model was applied to experimental data to predict the breakthrough curves using linear regression and to determine the characteristic parameters of the packed bed column. Bed depth/service time analysis (BDST) model was used to investigate the effect of bed depth on breakthrough curves. The results showed that Thomas model was suitable for the normal description of breakthrough curve at the experimental condition. The data were in good agreement with BDST model with R2 > 0.98. Statistical analyses were performed on fluoride removal obtained from different flow rates using SPSS16 software by applying Kruskal- Wallis test. These findings suggested that PAN-oxime-nano Fe2O3 in the column structure presents a great potential in removal of nitrate from aqueous solutions. PMID:25045525

  5. Packed column supercritical fluid chromatographic separation and estimation of acetaminophen, diclofenac sodium and methocarbamol in pharmaceutical dosage forms.

    PubMed

    Patil, S T; Sundaresan, M; Bhoir, I C; Bhagwat, A M

    1998-09-01

    A reproducible and fast method has been developed for the assay of acetaminophen, methocarbamol, and diclofenac sodium in bulk and drug forms using packed column supercritical fluid chromatography employing internal standard method. The analytes were resolved by elution with supercritical fluid carbon dioxide doped with 11.1% (v/v) methanol on a Shendon-Phenyl (250x4.6 mm) 5 mum column with detection monitored spectrophotometrically at 225 nm. The densities and polarities of the mobile phase were optimised from the effects of pressure, temperature and modifier concentration on chromatograhic figures like retention time (t(R), min), retention factor (k(')) etc. Modifier concentration proved to be the most effective means for changing both retention and selectivity. Calibration data and recovery of the drug from spiked concentrations were determined to assess the viability of the method. The supercritical fluid chromatography (SFC) method was directly compared to an HPLC assay, developed in the laboratory, of the same analytes. With respect to speed and use of organic solvents SFC was found to be superior, while in all other aspects the results were similar to HPLC. The method has been successfully used for the assay of two formulations containing a combination of (A) acetaminophen and methocarbamol and (B) acetaminophen and diclofenac sodium. There was no interference from excipients. The present work validates the recent proposition that supercritical fluid chromatography using CO(2) and modifiers is a viable, faster alternative to reverse phase HPLC. PMID:18967296

  6. Packed-column supercritical fluid chromatography of artemisinin (qinghaosu) with electron-capture detection.

    PubMed

    Mount, D L; Todd, G D; Navaratnam, V

    1995-04-01

    In this preliminary report, a supercritical fluid chromatographic method is described for the determination of artemisinin in whole blood. The chromatography is carried out on a 20 cm x 1 mm I.D. Deltabond cyano supercritical fluid chromatographic column with detection of the artemisinin via an electron-capture detector. The sample work-up uses a liquid-liquid extraction with hexane, giving a recovery of 82%. The current limit of detection using 1 ml of blood is 20 ng/ml. We speculate that the endoperoxide moiety accounts for the response to the electron-capture detector and thus provides a new approach by which this class of compounds may be analyzed. PMID:7655617

  7. Relative Transport Behavior of Escherichia coli O157:H7 and Salmonella enterica serovar Pullorum in Packed Bed Column Systems: Influence of Solution Chemistry and Cell Concentration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influence of solution chemistry and cell concentration on bacterial pathogen transport has been examined using Salmonella pullorum and Escherichia coli O157:H7. A packed bed column was employed to determine the transport behavior and deposition kinetics on real aquifer sand particles over a ran...

  8. 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.

  9. Longitudinal dispersion coefficient depending on superficial velocity of hydrogen isotopes flowing in column packed with zeolite pellets at 77.4 K

    SciTech Connect

    Kotoh, K.; Kubo, K.; Takashima, S.; Moriyama, S.T.; Tanaka, M.; Sugiyama, T.

    2015-03-15

    Authors have been developing a cryogenic pressure swing adsorption system for hydrogen isotope separation. In the problem of its design and operation, it is necessary to predict the concentration profiles developing in packed beds of adsorbent pellets. The profiling is affected by the longitudinal dispersion of gas flowing in packed beds, in addition to the mass transfer resistance in porous media of adsorbent pellets. In this work, an equation is derived for estimating the packed-bed dispersion coefficient of hydrogen isotopes, by analyzing the breakthrough curves of trace D{sub 2} or HD replacing H{sub 2} adsorbed in synthetic zeolite particles packed columns at the liquefied nitrogen temperature 77.4 K. Since specialized for hydrogen isotopes, this equation can be considered to estimate the dispersion coefficients more reliable for the cryogenic hydrogen isotope adsorption process, than the existing equations. (authors)

  10. Catalytic distillation structure

    DOEpatents

    Smith, L.A. Jr.

    1984-04-17

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

  11. Transport of biocolloids in water saturated columns packed with sand: Effect of grain size and pore water velocity

    NASA Astrophysics Data System (ADS)

    Syngouna, Vasiliki I.; Chrysikopoulos, Constantinos V.

    2011-11-01

    The main objective of this study was to evaluate the combined effects of grain size and pore water velocity on the transport in water saturated porous media of three waterborne fecal indicator organisms ( Escherichia coli, MS2, and ?X174) in laboratory-scale columns packed with clean quartz sand. Three different grain sizes and three pore water velocities were examined and the attachment behavior of Escherichia coli, MS2, and ?X174 onto quartz sand was evaluated. The mass recoveries of the biocolloids examined were shown to be highest for Escherichia coli and lowest for MS2. However, no obvious relationships between mass recoveries and water velocity or grain size could be established from the experimental results. The observed mean dispersivity values for each sand grain size were smaller for bacteria than coliphages, but higher for MS2 than ?X174. The single collector removal and collision efficiencies were quantified using the classical colloid filtration theory. Furthermore, theoretical collision efficiencies were estimated only for E. coli by the Interaction-Force-Boundary-Layer, and Maxwell approximations. Better agreement between the experimental and Maxwell theoretical collision efficiencies were observed.

  12. Transport of biocolloids in water saturated columns packed with sand: Effect of grain size and pore water velocity

    NASA Astrophysics Data System (ADS)

    Syngouna, Vasiliki I.; Chrysikopoulos, Constantinos V.

    2012-03-01

    The main objective of this study was to evaluate the combined effects of grain size and pore water velocity on the transport in water saturated porous media of three waterborne fecal indicator organisms (Escherichia coli, MS2, and ?X174) in laboratory-scale columns packed with clean quartz sand. Three different grain sizes and three pore water velocities were examined and the attachment behavior of Escherichia coli, MS2, and ?X174 onto quartz sand was evaluated. The mass recoveries of the biocolloids examined were shown to be highest for Escherichia coli and lowest for MS2. However, no obvious relationships between mass recoveries and water velocity or grain size could be established from the experimental results. The observed mean dispersivity values for each sand grain size were smaller for bacteria than coliphages, but higher for MS2 than ?X174. The single collector removal and collision efficiencies were quantified using the classical colloid filtration theory. Furthermore, theoretical collision efficiencies were estimated only for E. coli by the Interaction-Force-Boundary-Layer, and Maxwell approximations. Better agreement between the experimental and Maxwell theoretical collision efficiencies were observed.

  13. 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.

  14. Comparative study of HPLC column packings for the separation of aromatic and polar compounds in fossil fuel liquids

    SciTech Connect

    Matsunaga, A.; Kusayanagi, S.

    1981-03-29

    This paper reports a study on normal phase high performance liquid chromatography (HPLC) separations of aromatic and polar compounds using the following packing materials: Nucleosil NO/sub 2/; Nucleosil NH/sub 2/; Nucleosil CN; Nucleosil SA; Lichrosorb Si-5; Lichrosorb Al-5; and TSK 111. The retention data of model aromatic compounds on each stationary phase are summarized. The largest factor (K') was obtained by using Nucleosil NO/sub 2/ column, with the exception of activated alumina. The retention behavior of selected polar compounds is summarized. Good separation of polar compounds from aromatic hydrocarbons was obtained except for that on TSK 111. As TSK 111 has no polar group on it, interaction with polar group in sample molecule is weak. The rather strong retention of phenols and indoles will be due to their electrophilic nature. Polar compounds were preferentially retained on the stationary phases other than TSK 111. Gradient elution was carried out for rapid elution of strongly retained molecules. From the data obtained, it is considered that polar-polar interactions including hydrogen bonding or acid-base interaction are the predominant separation mechanism, although the effect of alkyl substitution, especially at sterically hindered positions to polar groups, is not negligible. HPLC separations on coal tar and heavy petroleum fractions are described and chromatograms are presented.

  15. Comparison between monolithic and particle-packed platinum C18 columns in HPLC determination of acidic and basic test mixtures.

    PubMed

    Atia, Noha N; York, Peter; Clark, Brian J

    2009-08-01

    Herein we report the results of a comparative study on the performance of Monolithic RP-18e and Platinum C(18) 3 mum columns for isocratic separation of acidic and basic test compounds. The inter- and intraday precision of different practical parameters including number of theoretical plates (N), capacity factor (K'), tailing factor (T(0.05)), and resolution (R(s)) were determined for both columns. Two different production batches were used for each column and batch to batch reproducibility of both columns was evaluated. The column backpressure drop over flow rate range 0.5-2 mL/min at the monolithic columns was two- to three-times lower than that on the platinum column without loss of the column efficiency. The plate heights were used to estimate the columns efficiency using Van Deemter plots. Both types of columns were able to separate the tested compounds well with sufficient resolution and peak symmetry but they differ in the analysis time and column backpressure, significantly. Monolithic column was more convenient as it enables the analytical run under low backpressure at shorter time with sufficient separation efficiency. PMID:19598165

  16. Efficiency for unretained solutes in packed column supercritical fluid chromatography II. Experimental results for elution of methane using large pressure drops.

    PubMed

    Xu, Wensheng; Peterson, Dawn L; Schroden, Jonathan J; Poe, Donald P

    2005-06-17

    At near-critical temperatures and pressures, experimental results for elution of methane with neat carbon dioxide on a 150 mm x 2.0 mm I.D. column packed with 5 microm porous silica with a bonded octylsilica stationary phase show much greater efficiency losses than predicted by theory if isothermal conditions are assumed. Experiments with insulated, air- and water-thermostatted columns demonstrate that significant axial and radial temperature gradients are produced by Joule-Thomson cooling of the mobile phase, and that radial temperature gradients can be a major cause of band spreading at low temperatures and pressures. The use of thermal insulation on the column can greatly improve efficiency under these conditions. PMID:16007994

  17. Efficient control system for low-concentration inorganic gases from a process vent stream: application of surfactants in spray and packed columns.

    PubMed

    Chein, Hungmin; Aggarwal, Shankar G; Wu, Hsin-Hsien

    2004-11-01

    Control of low-concentration pollutants from a semiconductor process vent stream using a wet-scrubbing technique is a challenging task to meet Taiwan environmental emission standards. An efficient wet-scrubber is designed on a pilot scale and tested to control low concentration acid and base waste-gas emission. The scrubber system consisted of two columns, i.e., a fine spray column [cutoff diameter (based on volume), Dv(50) = 15.63 microm; Sauter mean diameter (SMD) = 7.62 microm], which is especially efficient for NH3 removal as the pH of the spraying liquid is approximately 7 followed by a packed column with a scrubbing liquid pH approximately 9.0 mainly for acids removal. It is observed that use of the surfactants in low concentration about 10(-4) M and 10(-7) M in the spray liquid and in the scrubbing liquid, respectively, remarkably enhances the removal efficiency of the system. A traditional packed column (without the spray column and the surfactant) showed that the removal efficiencies of NH3, HF, and HCl for the inlet concentration range 0.2 to 3 ppm were (n = 5) 22.6+/-3.4%, 43.4+/-5.5%, and 40.4+/-7.4%, respectively. The overall efficiencies of the proposed system (the spray column and the packed column) in the presence of the surfactant in the spray liquid and in the scrubbing liquid forthese three species were found to increase significantly (n = 5) from 60.3+/-3.6 to 82.8+/-6.8%, 59.1+/-2.7 to 83.4+/-4.2%, and 56.2+/-7.3 to 81.0+/-6.7%, respectively. In this work, development of charge on the gas-liquid interface due to the surfactants has been measured and discussed. It is concluded that the presence of charge on the gas-liquid interface is the responsible factor for enhancement of the removal efficiency (mass-transfer in liquid phase). The effects of the type of surfactants, their chain length, concentration in liquid, etc. on the removal efficiency are discussed. Since the pilot tests were performed under the operating conditions similar to most of the wet-scrubbers operated in semiconductors manufacturing facilities for inorganic pollutants, this study can be applied to modify the existing wet-scrubbers to enhance the removal efficiencies, especially for low-concentration pollutants. PMID:15575298

  18. Determination of cadmium in river water samples by flame AAS after on-line preconcentration in mini-column packed with 2-aminothiazole-modified silica gel.

    PubMed

    Alcântara, Ilton L; Roldan, Paulo S; Castro, Gustavo R; Moraes, Fabrício V; Silva, Fábio A; Padilha, Cilene C F; Oliveira, Jorge D; Padilha, Pedro M

    2004-07-01

    A rapid and sensitive method was developed to determine trace levels of Cd2+ ions in an aqueous medium by flame atomic absorption spectrometry, using on-line preconcentration in a mini-column packed with 100 mg of 2-aminothiazol modified silica gel (SiAT). The Cd2+ ions were sorbed at pH 5.0. The preconcentrated Cd2+ ions were directly eluted from the column to the spectrometer's nebulizer-burner system using 100 microL of 2 mol L(-1) hydrochloric acid. A retention efficiency of over 95% was achieved. The enrichment factor (calculated as the ratio of slopes of the calibration graphs) obtained with preconcentrations in a mini-column packed with SiAT (A = -1.3 x 10(-3) + 1.8 x 10(-3)[Cd2+]) and without preconcentrations (A = 4 x 10(-5) + 3.5 x 10(-5)[Cd2+]), was 51 and the detection limit calculated was 0.38 microg L(-1). The preconcentration procedure was applied to determine trace levels of Cd in river water samples. The optimum preconcentration conditions are discussed herein. PMID:15293396

  19. Transport behavior of humic acid-modified nano-hydroxyapatite in saturated packed column: effects of Cu, ionic strength, and ionic composition.

    PubMed

    Wang, Dengjun; Chu, Lingyang; Paradelo, Marcos; Peijnenburg, Willie J G M; Wang, Yujun; Zhou, Dongmei

    2011-08-15

    The surfaces of nano-hydroxyapatite (nHAP) used for contaminated soil and groundwater remediation may be modified to render nHAP highly mobile in the subsurface. Humic acid (HA) is widely used to modify and stabilize colloid suspensions. In this work, column experiments were conducted to determine the effects of contaminant (e.g., Cu) concentration, ionic strength (IS), and ion composition (IC) on the transport behavior of HA-modified nHAP in saturated packed columns. IS and nature of the cation had strong effects on the deposition of nHAP, and the effect was greater for divalent than for monovalent cations. Divalent cations have a greater capacity to screen the surface charge of nHAP, and Ca(2+) bridges the HA-modified nHAP colloidal particles, which causes greater deposition. Moreover, Cu(2+) had a greater effect on the transport behavior than Ca(2+) due to their strong exchange with Ca(2+) of nHAP and its surface complexation with nHAP. The relative travel distance L(T), of the injected HA-modified nHAP colloids, ranges from less than one to several meters at varying Cu concentrations, ISs, and ICs in saturated packed columns. The results are crucial to evaluate the efficacy of nHAP on the remediation of contaminated soil and groundwater environments. PMID:21612786

  20. A Portable Liquid Chromatograph with a Battery-operated Compact Electroosmotic Pump and a Microfluidic Chip Device with a Reversed Phase Packed Column.

    PubMed

    Ishida, Akihiko; Fujii, Mitsutaka; Fujimoto, Takehiro; Sasaki, Shunsuke; Yanagisawa, Ichiro; Tani, Hirofumi; Tokeshi, Manabu

    2015-01-01

    A compact and lightweight liquid chromatography system is presented with overall dimensions of 26 cm width × 18 cm length × 21 cm height and weight of 2 kg. This system comprises a battery-operated compact electroosmotic pump, a manual injector, a microfluidic chip device containing a packed column and an electrochemical detector, and a USB bus-powered potentiostat. The pumping system was designed for microfluidic-based reversed-phase liquid chromatography in which an electroosmotically generated water stream pushes the mobile phase via a diaphragm for the output. The flow rate ranged from 0 to 10 μL/min and had a high degree of precision. The pumping system operated continuously for over 24 h with dry batteries. The column formed in the microfluidic device was packed with 3-μm ODS particles with a length of 30 mm and a diameter of 0.8 mm. The results presented herein demonstrate the performance of the pumping system and the column using alkylphenols, catecholamine, catechin, and amino acids. PMID:26561261

  1. Idle time in the washing and iron concentration in leachate removed: two basic parameters in the desulphurization of coal in a packed column.

    PubMed

    Cara, J; Aller, A; Otero, M; Morán, A

    2001-01-01

    Column biodesulphurization of coal is at the experimental stage and is influenced by many variables including temperature, pH, particle size, concentration of iron in solution, among others. Idle time in the washing process and the concentration of dissolved iron in the purged leachate are two variables with a definite effect on the yield of the desulphurization system. In the laboratory, several trials were run with columns packed with coal for different idle times: 1, 2, 3, 5, 6 and 7 days, and for different concentrations of iron in the purged leachate: 500 to 4,000 mg/l. The optimal values for the two variables; that is, those allowing for the highest desulphurization yields, were idle times of 3 and 5 days, which give an elimination of 56% and 49% of pyritic sulphur, respectively, and 3,000 mg/l of iron concentration in the purged leachate, giving a decrease in pyritic sulphur in coal of 57%. PMID:11234958

  2. Cryogenic distillation facility for isotopic purification of protium and deuterium

    NASA Astrophysics Data System (ADS)

    Alekseev, I.; Arkhipov, Ev.; Bondarenko, S.; Fedorchenko, O.; Ganzha, V.; Ivshin, K.; Kammel, P.; Kravtsov, P.; Petitjean, C.; Trofimov, V.; Vasilyev, A.; Vasyanina, T.; Vorobyov, A.; Vznuzdaev, M.

    2015-12-01

    Isotopic purification of the protium and deuterium is an important requirement of many physics experiments. A cryogenic facility for high-efficiency separation of hydrogen isotopes with a cryogenic distillation column as the main element is described. The instrument is portable, so that it can be used at the experimental site. It was designed and built at the Petersburg Nuclear Physics Institute, Gatchina, Russia. Fundamental operating parameters have been measured including a liquid holdup in the column packing, the pressure drops across the column and the purity of the product at different operating modes. A mathematical model describes expected profiles of hydrogen isotope concentration along the distillation column. An analysis of ortho-parahydrogen isomeric composition by gas chromatography was used for evaluation of the column performance during the tuning operations. The protium content during deuterium purification (≤100 ppb) was measured using gas chromatography with accumulation of the protium in the distillation column. A high precision isotopic measurement at the Institute of Particle Physics, ETH-Zurich, Switzerland, provided an upper bound of the deuterium content in protium (≤6 ppb), which exceeds all commercially available products.

  3. Cryogenic distillation facility for isotopic purification of protium and deuterium

    SciTech Connect

    Alekseev, I.; Arkhipov, Ev.; Bondarenko, S.; Fedorchenko, O.; Ganzha, V.; Ivshin, K.; Kravtsov, P. Trofimov, V.; Vasilyev, A.; Vasyanina, T.; Vorobyov, A.; Vznuzdaev, M.; Kammel, P.; Petitjean, C.

    2015-12-15

    Isotopic purification of the protium and deuterium is an important requirement of many physics experiments. A cryogenic facility for high-efficiency separation of hydrogen isotopes with a cryogenic distillation column as the main element is described. The instrument is portable, so that it can be used at the experimental site. It was designed and built at the Petersburg Nuclear Physics Institute, Gatchina, Russia. Fundamental operating parameters have been measured including a liquid holdup in the column packing, the pressure drops across the column and the purity of the product at different operating modes. A mathematical model describes expected profiles of hydrogen isotope concentration along the distillation column. An analysis of ortho-parahydrogen isomeric composition by gas chromatography was used for evaluation of the column performance during the tuning operations. The protium content during deuterium purification (≤100 ppb) was measured using gas chromatography with accumulation of the protium in the distillation column. A high precision isotopic measurement at the Institute of Particle Physics, ETH-Zurich, Switzerland, provided an upper bound of the deuterium content in protium (≤6 ppb), which exceeds all commercially available products.

  4. Cryogenic distillation facility for isotopic purification of protium and deuterium.

    PubMed

    Alekseev, I; Arkhipov, Ev; Bondarenko, S; Fedorchenko, O; Ganzha, V; Ivshin, K; Kammel, P; Kravtsov, P; Petitjean, C; Trofimov, V; Vasilyev, A; Vasyanina, T; Vorobyov, A; Vznuzdaev, M

    2015-12-01

    Isotopic purification of the protium and deuterium is an important requirement of many physics experiments. A cryogenic facility for high-efficiency separation of hydrogen isotopes with a cryogenic distillation column as the main element is described. The instrument is portable, so that it can be used at the experimental site. It was designed and built at the Petersburg Nuclear Physics Institute, Gatchina, Russia. Fundamental operating parameters have been measured including a liquid holdup in the column packing, the pressure drops across the column and the purity of the product at different operating modes. A mathematical model describes expected profiles of hydrogen isotope concentration along the distillation column. An analysis of ortho-parahydrogen isomeric composition by gas chromatography was used for evaluation of the column performance during the tuning operations. The protium content during deuterium purification (≤100 ppb) was measured using gas chromatography with accumulation of the protium in the distillation column. A high precision isotopic measurement at the Institute of Particle Physics, ETH-Zurich, Switzerland, provided an upper bound of the deuterium content in protium (≤6 ppb), which exceeds all commercially available products. PMID:26724068

  5. GraSPI (Graphical Structured Packing Interface)

    Energy Science and Technology Software Center (ESTSC)

    2004-06-10

    GraSPI is a collection of macros (computer programs) written to work in concert with Fluent Inc. software GAMBIT and FLUENT for modeling and design of structured packing columns used in the chemical industry (the application focus is in distillation but other applications such as gas absorbers, and other chemical contactors can also be analyzed). GraSPI is an accessory to GAMBIT and FLUENT that drives the process of complex geometry creation, domain setup, and mesh generation.more » In addition, GraSPI manages automatic flow analysis in the aforementioned domain via either serial or parallel computing using FLUENT. A library of typical commercial structured packing elements is included in GraSPI, so is the capability for user-defined creation of new packings.« less

  6. Evolution of strategies to achieve baseline separation of ten anionic, water-soluble sulfated estrogens via achiral packed column supercritical fluid chromatography.

    PubMed

    Patel, M A; Hardink, M A; Wrisely, L; Riley, F W; Hudalla, C J; Ashraf-Khorassani, M; Taylor, L T

    2014-11-28

    Near baseline separation of ten sulfated sodium salts of various structurally related estrogens employing a variety of bonded stationary phase packed columns was obtained using a conventional supercritical fluid chromatograph coupled with UV detection. Critical pairs 2/3 (8,9-dehydroestrone/17β-dihydroequilin) and 6/7 (17α-estradiol or 17α-dihydroequilin/estrone), however, failed to baseline separate. In all preliminary separations, 10mM ammonium acetate and variable percentages of H2O were initially used as co-additives in conjunction with methanol as a modifier. Different modifier programs and temperatures were employed to optimize the separation in a timely manner. A 2-ethylpyridine column provided the best separation compared to bare silica, diol, and cyano-based bonded phase columns. The employment of both salt and water as additives to the methanol-modified CO2 mobile phase suggested a mixed mode separation mechanism involving both ion pairing of each anionic sulfated estrogen with ammonium ion and hydrophilic interaction facilitated by partitioning of analyte between the aqueous solvated stationary phase and the aqueous component of the mobile phase. Upon more extensive study with either iso-propylamine or formic acid-ammonium formate buffer, the critical anionic pairs were 95% baseline resolved. PMID:25454148

  7. Synthesis and Development of Porous Polymeric Column Packing and Microchip Detectors for GC Analysis of Extraterrestrial Atmospheres

    NASA Technical Reports Server (NTRS)

    Shen, Thomas C.

    1999-01-01

    This report summarizes the last nine years research accomplishments under Cooperative Agreement NCC2-650 between NASA, Ames Research Center and SETI Institute. Four Major research tasks are conducted: 1. Gas chromatography column development. 2. Pyrosensor development. 3. Micro-machining gas chromatography instrument development. 4. Amino acid analysis and high molecular weight polyamino acid synthesis under prebiotic conditions. The following describes these results.

  8. Ammonia removal from wastewaters using natural Australian zeolite. 2. Pilot-scale study using continuous packed column process

    SciTech Connect

    Cooney, E.L.; Booker, N.A.; Shallcross, D.C.; Stevens, G.W.

    1999-10-01

    A pilot-scale process was designed and operated to investigate the continuous removal of ammonia from sewage using natural zeolite from Australia. The process consisted of a fixed-bed ion-exchange system operated in the downflow mode. Evaluation of the pilot process was initially undertaken for ammonia removal from tap water spiked with ammonium chloride to provide performance data in the absence of competing cations. The performance of the pilot process was then assessed using sewage as feed. Breakthrough curves were constructed for a range of treatment flow rates. Existing models for packed bed performance were shown to be able to predict the breakthrough behavior of the process. The results of a study are presented that show that Australian natural zeolite, clinoptilolite, may be successfully employed in a fixed-bed ion-exchange process to achieve high ammonia removal efficiencies from aqueous solution at rates commensurate with sand filtration. The rate of uptake of ammonium by the zeolite is sufficient to support a continuous high rate process.

  9. Investigation related to hydrogen isotopes separation by cryogenic distillation

    SciTech Connect

    Bornea, A.; Zamfirache, M.; Stefanescu, I.; Preda, A.; Balteanu, O.; Stefan, I.

    2008-07-15

    Research conducted in the last fifty years has shown that one of the most efficient techniques of removing tritium from the heavy water used as moderator and coolant in CANDU reactors (as that operated at Cernavoda (Romania)) is hydrogen cryogenic distillation. Designing and implementing the concept of cryogenic distillation columns require experiments to be conducted as well as computer simulations. Particularly, computer simulations are of great importance when designing and evaluating the performances of a column or a series of columns. Experimental data collected from laboratory work will be used as input for computer simulations run at larger scale (for The Pilot Plant for Tritium and Deuterium Separation) in order to increase the confidence in the simulated results. Studies carried out were focused on the following: - Quantitative analyses of important parameters such as the number of theoretical plates, inlet area, reflux flow, flow-rates extraction, working pressure, etc. - Columns connected in series in such a way to fulfil the separation requirements. Experiments were carried out on a laboratory-scale installation to investigate the performance of contact elements with continuous packing. The packing was manufactured in our institute. (authors)

  10. Removal of nickel(II) ions from aqueous solution using crab shell particles in a packed bed up-flow column.

    PubMed

    Vijayaraghavan, K; Jegan, J; Palanivelu, K; Velan, M

    2004-09-10

    This paper investigates the ability of crab shell to remove nickel(II) ions from aqueous solution in a packed bed up-flow column with an internal diameter of 2 cm. The experiments were performed with different bed heights (15-25 cm) and using different flow rates (5-20 ml/min) in order to obtain experimental breakthrough curves. The bed depth service time (BDST) model was used to analyze the experimental data and the model parameters were evaluated. The column regeneration studies were carried out for seven sorption-desorption cycles. The elutant used for the regeneration of the sorbent was 0.01 M EDTA (disodium) solution at pH 9.8 adjusted using NH4OH. Due to continuous usage of crab shell, a performance loss was observed as the breakthrough curves become more flattened also indicated by the broadened mass transfer zone. The breakthrough time decreased uniformly from 28.1 to 9.5 h as the cycles progressed from one to seven, whereas nickel uptake remained approximately constant throughout the seven cycles. The life-factors for crab shell in terms of critical bed length and breakthrough time were found to be 1.1 cm/cycle and 0.17 per cycle, respectively. The elution efficiency was greater than 99.1% in all the seven cycles. The pH profiles during both sorption and desorption process were also reported. In sorption cycles, there was a sudden raise in pH in the early part of the process and then the pH decreased as the time progressed. In desorption cycles, pH decreased in initial stages and followed by gradual increase in pH, which eventually reached the pH of the inlet elutant. PMID:15363535

  11. Successive pretreatment and enzymatic saccharification of sugarcane bagasse in a packed bed flow-through column reactor aiming to support biorefineries.

    PubMed

    Terán-Hilares, R; Reséndiz, A L; Martínez, R T; Silva, S S; Santos, J C

    2016-03-01

    A packed bed flow-through column reactor (PBFTCR) was used for pretreatment and subsequent enzymatic hydrolysis of sugarcane bagasse (SCB). Alkaline pretreatment was performed at 70°C for 4h with fresh 0.3M NaOH solution or with liquor recycled from a previous pretreatment batch. Scheffersomyces stipitis NRRL-Y7124 was used for fermentation of sugars released after enzymatic hydrolysis (20FPUg(-1) of dry SCB). The highest results for lignin removal were 61% and 52%, respectively, observed when using fresh NaOH or the first reuse of the liquor. About 50% of cellulosic and 57% of hemicellulosic fractions of pretreated SCBs were enzymatically hydrolyzed and the maximum ethanol production was 23.4gL(-1) (ethanol yield of 0.4gpgs(-1)), with near complete consumption of both pentoses and hexoses present in the hydrolysate during the fermentation. PBFTCR as a new alternative for SCB-biorefineries is presented, mainly considering its simple configuration and efficiency for operating with a high solid:liquid ratio. PMID:26720138

  12. A Comprehensive Real-World Distillation Experiment

    ERIC Educational Resources Information Center

    Kazameas, Christos G.; Keller, Kaitlin N.; Luyben, William L.

    2015-01-01

    Most undergraduate mass transfer and separation courses cover the design of distillation columns, and many undergraduate laboratories have distillation experiments. In many cases, the treatment is restricted to simple column configurations and simplifying assumptions are made so as to convey only the basic concepts. In industry, the analysis of a…

  13. A Comprehensive Real-World Distillation Experiment

    ERIC Educational Resources Information Center

    Kazameas, Christos G.; Keller, Kaitlin N.; Luyben, William L.

    2015-01-01

    Most undergraduate mass transfer and separation courses cover the design of distillation columns, and many undergraduate laboratories have distillation experiments. In many cases, the treatment is restricted to simple column configurations and simplifying assumptions are made so as to convey only the basic concepts. In industry, the analysis of a

  14. Evaluation of monolithic and sub 2 microm particle packed columns for the rapid screening for illicit drugs--application to the determination of drug contamination on Irish euro banknotes.

    PubMed

    Bones, Jonathan; Macka, Mirek; Paull, Brett

    2007-03-01

    A study comparing recently available 100 x 3 mm id, 200 x 3 mm id monolithic reversed-phase columns with a 50 x 2.1 mm id, 1.8 microm particle packed reversed-phase columns was carried out to determine the most efficient approach (using traditional van Deemter analysis and a modern kinetic plot approach) for the rapid screening of samples for 16 illicit drugs and associated metabolites. A plot of column backpressure versus plate number (N) showed a significant advantage of using the monolithic phases, with the 20 cm monolithic column exhibiting a maximum 15,000 plates at a column backpressure of approximately 70 bar, compared to approximately 7000 plates at 150 bar for the 5 cm 1.8 microm particle packed column. Optimum linear velocities were found to be 0.40 mm s(-1), 0.52 mm s(-1) and 0.98 mm s(-1) for the three above columns, respectively. The 20 cm monolithic column was subsequently applied to the separation and determination of illicit drug contamination on Irish euro banknotes, using methanol extraction followed by LC-MS/MS. Method performance data showed that the new LC-MS/MS method was significantly more sensitive than previous GC-MS/MS based methods for this application, with detection limits in the pg note(-1) region, based upon a 20 microL standard injection. All of the notes examined tested positive for trace quantities of cocaine, with benzoylecgonine detected on 12 of the 45 notes sampled. Traces of heroin were also detected on three of the 45 notes. PMID:17325753

  15. Analysis of F2-isoprostanes in plasma of pregnant women by HPLC-MS/MS using a column packed with core-shell particles

    PubMed Central

    Larose, Jessica; Julien, Pierre; Bilodeau, Jean-François

    2013-01-01

    Plasma F2-isoprostanes (F2-isoPs) are reliable biomarkers of oxidative stress. Several possible F2-isoPs are generated by the oxidation of arachidonic acid esterified in phospholipids. The separation of these isomers represents a technical challenge for rapid and selective determination. We have developed a HPLC-MS/MS method for the simultaneous determination of seven plasma F2-isoPs, namely 8-iso-15(R)-prostaglandin F2α (PGF2α), 8-iso-PGF2α, 15(R)-PGF2α, iPF2α-IV, iPF2α-VI, 5-iPF2α-VI, and (±)5-8,12-iso-iPF2α-VI. We have validated this method in plasma of pregnant women, a mild physiological oxidative stress known to increase F2-isoPs. Thus, plasma samples of women collected at the third trimester of pregnancy (n = 20) were subjected to alkaline hydrolysis followed by liquid-liquid extraction in order to extract total F2-isoPs. The F2-isoPs were separated within 16.5 min using a column packed with core-shell particles. The class VI isomers were the most abundant, accounting for 65% of the total level of all quantified F2-isoPs in plasma of pregnant women (P < 0.05). The 15(R)-PGF2α was the most abundant of the class III isomers quantified. This method allowed fast and selective separation of seven isomers from three different classes of F2-isoP regioisomers. PMID:23431046

  16. Design of processes with reactive distillation line diagrams

    SciTech Connect

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

    1997-08-01

    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 the reactive distillation line diagrams, it can be decided whether a column with two feed stages is required. On the basis of the reaction space concept, a procedure for identification of reactive distillation processes is developed, in which the reactive distillation column has to be divided into reactive and nonreactive sections. This can be necessary to overcome the limitations in separation which result from the chemical equilibrium. The concentration profile of this combined reactive/nonreactive distillation column is estimated using combined reactive/nonreactive distillation lines.

  17. Evaluation of the kinetic performance of new prototype 2.1mm×100mm narrow-bore columns packed with 1.6μm 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 1.6μm 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 1.6μm core-shell particles since these columns provide intrinsic efficiencies higher than 400,000 plates per meter. PMID:24572546

  18. Method for packing chromatographic beds

    DOEpatents

    Freeman, David H.; Angeles, Rosalie M.; Keller, Suzanne

    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.

  19. A novel chip device based on wired capillary packed with high performance polymer-based monolith for HPLC: reproducibility in preparation processes to obtain long columns.

    PubMed

    Hosoya, Ken; Sakamoto, Mari; Akai, Kunihiko; Mori, Tomoko; Kubo, Takuya; Kaya, Kunimitsu; Okada, Kazuma; Tsujioka, Norio; Tanaka, Nobuo

    2008-01-01

    This report describes the development of novel wired chip devices for mu-HPLC analyses. The monolithic capillary column to be wired was prepared using a tri-functional epoxy monomer, tris(2,3-epoxypropyl)isocyanurate with a diamine, 4-[(4-aminocyclohexyl)methyl]cyclohexylamine. The prepared column was evaluated by SEM observation of the sectional structure of column and micro-HPLC. In addition, the reproducibility in the preparation of long capillary columns having nearly 1 m length was extensively examined for applications of novel wired chip devices. The authors demonstrated that the monolithic structure of the prepared long capillary could be finely controlled under the strictly maintained operational conditions and thus the relative standard deviation (RSD) of the column properties such as the number of theoretical plates, retention factor, and permeability could be well controlled to become less than 10%. Furthermore, the wired chip device column showed that its high performance was kept even after chip preparation. PMID:18187864

  20. Effect of an open tube in series with a packed capillary column on liquid chromatographic performance. The influence of particle diameter, temperature, and system pressure.

    PubMed

    Xu, Hongjuan; Weber, Stephen G

    2009-02-27

    A postcolumn reactor or a simple open tube connecting a capillary column to, for example, a mass spectrometer affects the performance of a capillary liquid chromatography system in two ways: stealing pressure from the column and adding band-spreading. This effect is especially intolerable in fast separations. Our calculations show that in the presence of a 25 microm radius postcolumn reactor, column (50 microm radius) efficiency (number of theoretical plates) is severely reduced by more than 75% with a t(0) of 10s and a particle diameter from 1 to 5 microm for unretained solutes at room temperature. Therefore, it is necessary to minimize the reactor's effect and to improve the column efficiency by optimizing postcolumn conditions. We derived an equation that defines the observed number of theoretical plates (N(obs)) taking into account the two effects stated above, which is a function of the maximum pressure P(m), the particle diameter d(p), the reactor radius a(r), the column radius a(c), the desired dead time t(0), the column temperature T and zone capacity factor k''. Poppe plots were obtained by calculations using this equation. The results show that for a t(0) shorter than 18s, a P(m) of 4000 psi, and a d(p) of 1.7 microm, a 5 microm radius reactor has to be used. Such a small reactor is difficult to fabricate. Fortunately, high temperature helps to minimize the reactor effect so that reactors with manageable radius (larger than 12.5 microm) can be used in many practical conditions. Furthermore, solute retention diminishes the influence of a postcolumn reactor. Thus, a 12.5 microm reactor supersedes a 5 microm reactor for retained solutes even at a t(0) of 5s (k''>3.8, or k'>2.0). PMID:19150071

  1. Distributive Distillation Enabled by Microchannel Process Technology

    SciTech Connect

    Arora, Ravi

    2013-01-22

    The application of microchannel technology for distributive distillation was studied to achieve the Grand Challenge goals of 25% energy savings and 10% return on investment. In Task 1, a detailed study was conducted and two distillation systems were identified that would meet the Grand Challenge goals if the microchannel distillation technology was used. Material and heat balance calculations were performed to develop process flow sheet designs for the two distillation systems in Task 2. The process designs were focused on two methods of integrating the microchannel technology – 1) Integrating microchannel distillation to an existing conventional column, 2) Microchannel distillation for new plants. A design concept for a modular microchannel distillation unit was developed in Task 3. In Task 4, Ultrasonic Additive Machining (UAM) was evaluated as a manufacturing method for microchannel distillation units. However, it was found that a significant development work would be required to develop process parameters to use UAM for commercial distillation manufacturing. Two alternate manufacturing methods were explored. Both manufacturing approaches were experimentally tested to confirm their validity. The conceptual design of the microchannel distillation unit (Task 3) was combined with the manufacturing methods developed in Task 4 and flowsheet designs in Task 2 to estimate the cost of the microchannel distillation unit and this was compared to a conventional distillation column. The best results were for a methanol-water separation unit for the use in a biodiesel facility. For this application microchannel distillation was found to be more cost effective than conventional system and capable of meeting the DOE Grand Challenge performance requirements.

  2. A comparison of the properties of polyurethane immobilised Sphagnum moss, seaweed, sunflower waste and maize for the biosorption of Cu, Pb, Zn and Ni in continuous flow packed columns.

    PubMed

    Zhang, Yue; Banks, Charles

    2006-02-01

    The biosorption of Cu, Pb, Zn and Ni from a mixed solution of the metals was investigated in continuous flow packed columns containing polyurethane immobilised biomass. The characteristics and biosorption properties of Sphagnum moss, the brown seaweed Ascophyllum nodosum, waste biomass from the preparation of sunflower oil, and whole plant maize were compared. All the biomass types showed a preference for the sequestration of Pb followed by Cu, with Ni and Zn having roughly equal affinity. With continuous metal loading to the column there was an initial binding of all metals and then a displacement of the lower affinity metals by those with a high affinity. This led to a chromatographic effect in the column with breakthrough concentrations for low-affinity metals higher than the concentration in the feed. A similar phenomenon was found on desorption using acidic solutions where low-affinity metals were desorbed preferentially. The results also indicated that despite competitive displacement of one metal species by another the biomass appeared to succeed in retaining some low-affinity metal species indicating that there may be selective sites present with different affinity characteristics. When using a multi-metal solution with Cu, Pb, Zn and Ni at equal 10 mgl(-1) concentrations as column influent, the total quantities of metal sequestered were: seaweed, 117.3 mg g(-1); sunflower waste, 33.2 mg g(-1); Sphagnum moss, 32.5 mg g(-1); and maize, 2.3 mg g(-1). The use of an acid base potentiometric titration showed a relationship between the number of acid functional groups and biosorption capacity, although this was not proportional for the biomass types studied. It can, however, be used in conjunction with a simple classification of metals into high and low-affinity bands to make a preliminary assessment of a biosorption system. PMID:16448685

  3. Attachment of Acidithiobacillus ferrooxidans and Leptospirillum ferriphilum cultured under varying conditions to pyrite, chalcopyrite, low-grade ore and quartz in a packed column reactor.

    PubMed

    Africa, Cindy-Jade; van Hille, Robert P; Harrison, Susan T L

    2013-02-01

    The attachment of Acidithiobacillus ferrooxidans and Leptospirillum ferriphilum spp. grown on ferrous medium or adapted to a pyrite mineral concentrate to four mineral substrata, namely, chalcopyrite and pyrite concentrates, a low-grade chalcopyrite ore (0.5 wt%) and quartzite, was investigated. The quartzite represented a typical gangue mineral and served as a control. The attachment studies were carried out in a novel particle-coated column reactor. The saturated reactor containing glass beads, which were coated with fine mineral concentrates, provided a quantifiable surface area of mineral concentrate and maintained good fluid flow. A. ferrooxidans and Leptospirillum spp. had similar attachment characteristics. Enhanced attachment efficiency occurred with bacteria grown on sulphide minerals relative to those grown on ferrous sulphate in an ore-free environment. Selective attachment to sulphide minerals relative to gangue materials occurred, with mineral adapted cultures attaching to the minerals more efficiently than ferrous grown cultures. Mineral-adapted cultures showed highest levels of attachment to pyrite (74% and 79% attachment for A. ferrooxidans and L. ferriphilum, respectively). This was followed by attachment of mineral-adapted cultures to chalcopyrite (63% and 58% for A. ferrooxidans and L. ferriphilum, respectively). A. ferrooxidans and L. ferriphilum exhibited lower levels of attachment to low-grade ore and quartz relative to the sulphide minerals. PMID:22410741

  4. 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 5.7910(4), 7.3110(4) and 2.5210(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

  5. Packing frontiers expanded through process technology

    SciTech Connect

    Hodel, A.E.

    1984-02-01

    Manufacturers can expect to continue to apply the advantages of packing in the mass and heat transfer applications. The availability of materials, technology and improved packing with high efficiencies and low pressure drop is expected to stimulate additional advances in packing applications in the chemical processing industries. In hydrocarbon process applications where the column design objective is to reduce costs and achieve higher levels of yield from fixed amounts of stock, packing technology is replacing trays to reduce energy consumption, and increase yields.

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

    PubMed

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

    2016-02-01

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

  7. Pack Saddle

    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...

  8. Distillation tray structural parameter study: Phase 1

    NASA Technical Reports Server (NTRS)

    Winter, J. Ronald

    1991-01-01

    The purpose here is to identify the structural parameters (plate thickness, liquid level, beam size, number of beams, tray diameter, etc.) that affect the structural integrity of distillation trays in distillation columns. Once the sensitivity of the trays' dynamic response to these parameters has been established, the designer will be able to use this information to prepare more accurate specifications for the construction of new trays. Information is given on both static and dynamic analysis, modal response, and tray failure details.

  9. Selective extraction and analysis of catecholamines in rat blood microdialysate by polymeric ionic liquid-diphenylboric acid-packed capillary column and fast separation in high-performance liquid chromatography-electrochemical detector.

    PubMed

    Zhou, Xinguang; Zhu, Anwei; Shi, Guoyue

    2015-08-28

    Concentration of blood catecholamines (CAs) is linked to a host of cardiovascular diseases, including hypertension and stenocardia. The matrix interferences and low concentration require tedious sample pretreatment methods before quantitative analysis by the gold standard method of high-performance liquid chromatography-electrochemical detector (HPLC-ECD). Solid phase extraction (SPE) has been widely used as the pretreatment technique. Here, a facile polymeric ionic liquid (PIL)-diphenylboric acid (DPBA)-packed capillary column was prepared to selectively extract dopamine (DA), noradrenaline (NE) and epinephrine (E) prior to their quantitative analysis by a fast separation in HPLC-ECD method, while microdialysis sampling method was applied to get the analysis sample. Parameters that influenced desorption efficiency, such as pH, salt concentration, acetonitrile content and wash time, were examined and optimized. The proposed method, combining microdialysis sampling technique, SPE and HPLC-ECD system, was successfully applied to detect CAs in rat blood microdialysate with high sensitivity and selectivity in small sample volumes (5-40μl) and a short analysis time (8min), yielding good reproducibility (RSD 6.5-7.7%) and spiked recovery (91-104.4%). PMID:26206631

  10. Analytical approach to determining human biogenic amines and their metabolites using eVol microextraction in packed syringe coupled to liquid chromatography mass spectrometry method with hydrophilic interaction chromatography column.

    PubMed

    Konieczna, Lucyna; Roszkowska, Anna; Synakiewicz, Anna; Stachowicz-Stencel, Teresa; Adamkiewicz-Drożyńska, Elżbieta; Bączek, Tomasz

    2016-04-01

    Analysis of biogenic amines (BAs) in different human samples provides insight into the mechanisms of various biological processes, including pathological conditions, and thus may be very important in diagnosing and monitoring several neurological disorders and cancerous tumors. In this work, we developed a simple and fast procedure using a digitally controlled microextraction in packed syringe (MEPS) coupled to liquid chromatography mass spectrometry (LC-MS) method for simultaneous determination of biogenic amines, their precursors and metabolites in human plasma and urine samples. The separation of 12 low molecular weight and hydrophilic molecules with a wide range of polarities was achieved with hydrophilic interaction chromatography (HILIC) column without derivatization step in 12min. MEPS was implemented using the APS sorbent in semi-automated analytical syringe (eVol(®)) and small volume of urine and plasma samples, 50µL and 100μL, respectively. We evaluated important parameters influencing MEPS efficiency, including stationary phase selection, sample pH and volume, number of extraction cycles, and washing and elution volumes. In optimized MEPS conditions, the analytes were eluted by 3×50μL of methanol with 0.1% formic acid. The chromatographic separation of analytes was performed on XBridge Amide™ BEH analytical column (3.0mm×100mm, 3.5µm) using gradient elution with mobile phase consisting of phase A: 10mM ammonium formate buffer in water pH 3.0 and phase B: 10mM ammonium formate buffer in acetonitrile pH 3.0. The LC-HILIC-MS method was validated and, in optimum conditions, presented good linearity in concentration range within 10-2000ng/mL for all the analytes with a determination coefficient (r(2)) higher than 0.999 for plasma and urine samples. Method recovery ranged within 87.6-104.3% for plasma samples and 84.2-98.6% for urine samples. The developed method utilizing polar APS sorbent along with polar HILIC column was applied for simultaneous bioanalysis of trace amounts of polar endogenous biogenic amines in real human urine and plasma samples. PMID:26838416

  11. Integrated process of distillation with side reactors for synthesis of organic acid esters

    DOEpatents

    Panchal, Chandrakant B; Prindle, John C; Kolah, Aspri; Miller, Dennis J; Lira, Carl T

    2015-11-04

    An integrated process and system for synthesis of organic-acid esters is provided. The method of synthesizing combines reaction and distillation where an organic acid and alcohol composition are passed through a distillation chamber having a plurality of zones. Side reactors are used for drawing off portions of the composition and then recycling them to the distillation column for further purification. Water is removed from a pre-reactor prior to insertion into the distillation column. An integrated heat integration system is contained within the distillation column for further purification and optimizing efficiency in the obtaining of the final product.

  12. Distillation sequence for the purification and recovery of hydrocarbons

    DOEpatents

    Reyneke, Rian; Foral, Michael; Papadopoulos, Christos G.; Logsdon, Jeffrey S.; Eng, Wayne W. Y.; Lee, Guang-Chung; Sinclair, Ian

    2007-12-25

    This invention is an improved distillation sequence for the separation and purification of ethylene from a cracked gas. A hydrocarbon feed enters a C2 distributor column. The top of the C2 distributor column is thermally coupled to an ethylene distributor column, and the bottoms liquid of a C2 distributor column feeds a deethanizer column. The C2 distributor column utilizes a conventional reboiler. The top of the ethylene distributor is thermally coupled with a demethanizer column, and the bottoms liquid of the ethylene distributor feeds a C2 splitter column. The ethylene distributor column utilizes a conventional reboiler. The deethanizer and C2 splitter columns are also thermally coupled and operated at a substantially lower pressure than the C2 distributor column, the ethylene distributor column, and the demethanizer column. Alternatively, a hydrocarbon feed enters a deethanizer column. The top of the deethanizer is thermally coupled to an ethylene distributor column, and the ethylene distributor column utilizes a conventional reboiler. The top of the ethylene distributor column is thermally coupled with a demethanizer column, and the bottoms liquid of the ethylene distributor column feeds a C2 splitter column. The C2 splitter column operates at a pressure substantially lower than the ethylene distributor column, the demethanizer column, and the deethanizer column.

  13. Setting the Pressure at Which to Conduct a Distillation.

    ERIC Educational Resources Information Center

    Barduhn, Allen J.

    1984-01-01

    Discusses how pressure setting is determined for distillation columns, examining factors which must be considered when optimizing design for economical balance. Also discusses the basics of heat exchangers and cites a common problem with pressure differences. (JM)

  14. Distillation with Vapour Compression. An Undergraduate Experimental Facility.

    ERIC Educational Resources Information Center

    Pritchard, Colin

    1986-01-01

    Discusses the need to design distillation columns that are more energy efficient. Describes a "design and build" project completed by two college students aimed at demonstrating the principles of vapour compression distillation in a more energy efficient way. General design specifications are given, along with suggestions for teaching and…

  15. Distillation with Vapour Compression. An Undergraduate Experimental Facility.

    ERIC Educational Resources Information Center

    Pritchard, Colin

    1986-01-01

    Discusses the need to design distillation columns that are more energy efficient. Describes a "design and build" project completed by two college students aimed at demonstrating the principles of vapour compression distillation in a more energy efficient way. General design specifications are given, along with suggestions for teaching and

  16. Technique of ethanol food grade production with batch distillation and dehydration using starch-based adsorbent

    NASA Astrophysics Data System (ADS)

    Widjaja, Tri; Altway, Ali; Ni'mah, Hikmatun; Tedji, Namira; Rofiqah, Umi

    2015-12-01

    Development and innovation of ethanol food grade production are becoming the reasearch priority to increase economy growth. Moreover, the government of Indonesia has established regulation for increasing the renewable energy as primary energy. Sorghum is cerealia plant that contains 11-16% sugar that is optimum for fermentation process, it is potential to be cultivated, especially at barren area in Indonesia. The purpose of this experiment is to learn about the effect of microorganisms in fermentation process. Fermentation process was carried out batchwise in bioreactor and used 150g/L initial sugar concentration. Microorganisms used in this experiment are Zymomonas mobilis mutation (A3), Saccharomyces cerevisiae and mixed of Pichia stipitis. The yield of ethanol can be obtained from this experiment. For ethanol purification result, distillation process from fermentation process has been done to search the best operation condition for efficiency energy consumption. The experiment for purification was divided into two parts, which are distillation with structured packing steel wool and adsorption (dehydration) sequencely. In distillation part, parameters evaluation (HETP and pressure drop) of distillation column that can be used for scale up are needed. The experiment was operated at pressure of 1 atm. The distillation stage was carried out at 85 °C and reflux ratio of 0.92 with variety porosities of 20%, 40%, and 60%. Then the adsorption process was done at 120°C and two types of adsorbent, which are starch - based adsorbent with ingredient of cassava and molecular sieve 3A, were used. The adsorption process was then continued to purify the ethanol from impurities by using activated carbon. This research shows that the batch fermentation process with Zymomonas mobilis A3 obtain higher % yield of ethanol of 40,92%. In addition to that, for purification process, the best operation condition is by using 40% of porosity of stuctured packing steel wool in distillation stage and starch-based adsorbent in adsorption stage, which can obtain ethanol content of 92,15% with acetic acid percentage of 0,001% and the rest is water. This result is qualified for ethanol food grade specification which is between 90 - 94 % of ethanol with maximum percentage of acetic acid is 0,003%, and passes in fusel oil and isopropyl alcohol test.

  17. Kinetic Method for Hydrogen-Deuterium-Tritium Mixture Distillation Simulation

    SciTech Connect

    Sazonov, A.B.; Kagramanov, Z.G.; Magomedbekov, E.P.

    2005-07-15

    Simulation of hydrogen distillation plants requires mathematical procedures suitable for multicomponent systems. In most of the present-day simulation methods a distillation column is assumed to be composed of theoretical stages, or plates. However, in the case of a multicomponent mixture theoretical plate does not exist.An alternative kinetic method of simulation is depicted in the work. According to this method a system of mass-transfer differential equations is solved numerically. Mass-transfer coefficients are estimated with using experimental results and empirical equations.Developed method allows calculating the steady state of a distillation column as well as its any non-steady state when initial conditions are given. The results for steady states are compared with ones obtained via Thiele-Geddes theoretical stage technique and the necessity of using kinetic method is demonstrated. Examples of a column startup period and periodic distillation simulations are shown as well.

  18. Multipartite nonlocality distillation

    SciTech Connect

    Hsu, Li-Yi; Wu, Keng-Shuo

    2010-11-15

    The stronger nonlocality than that allowed in quantum theory can provide an advantage in information processing and computation. Since quantum entanglement is distillable, can nonlocality be distilled in the nonsignalling condition? The answer is positive in the bipartite case. In this article the distillability of the multipartite nonlocality is investigated. We propose a distillation protocol solely exploiting xor operations on output bits. The probability-distribution vectors and matrix are introduced to tackle the correlators. It is shown that only the correlators with extreme values can survive the distillation process. As the main result, the amplified nonlocality cannot maximally violate any Bell-type inequality. Accordingly, a distillability criterion in the postquantum region is proposed.

  19. Analysis of Breakthrough Profiles Based on Gamma Ray Emission Along Loaded Packed Bed Columns: Comparative Evaluation of Ionsiv IE-911 and Chabazite Zeolite for the Removal of Radiostrontium and Cesium from Groundwater

    SciTech Connect

    Bostick, D.T.; DePaoli, S.M.; Lucero, A.J.

    1999-10-18

    A gamma counting system has been assembled that can profile the breakthrough fronts of gamma-emitting radioisotopes longitudinally and axially along a loaded column. This profiling technique has been particularly useful in columns studies such as those performed with IONSP IE-911, a crystalline silicotitanate (CST) manufactured by UOP, in which unusually long operating times are required to observe cesium breakthrough in column effluent. The length of the mass transfer zone and extent of column saturation can be detected early in a column study by viewing the relative emission of gamma emitters along I the length of the column. In this study, gamma scans were used to analyze loaded CST and zeolite columns used in the treatment of process wastewater simulant and actual groundwater. Results indicate good run-to-run reproductibility in acquiring the scans. The longitudinal gamma scans for both {sup 90}Sr and {sup 137}Cs conformed with breakthrough results reported on the basis of column effluent activity. Although not obvious from data obtained by monitoring effluent activity, the gamma scans indicated that both cesium and strontium in the saturated zone of the CST column are slowly displaced by the higher levels of groundwater cations and are then resorbed further down the column. This displacement phenomenon identified by gamma scans was verified using data from a zeolite column, in which both the gamma scan and column effluent data exhibited radionuclide displacement by groundwater cations. The gamma emission intensities from the CST column runs are used to quantitate and compare the distribution coefficient and loading capacity of {sup 137}Cs on CST versus zeolite.

  20. Don`t overlook extractive distillation

    SciTech Connect

    Lee, F.M.; Gentry, J.C.

    1997-10-01

    One of the most useful ways to separate chemicals having close relative volatilities is to employ selective solvents. These solvents take advantage of the nonideality of a mixture of components having different chemical structures. Extractive distillation uses a third component to effect the chemical separation. Here, though, the extractive agent simply creates or enhances the volatility difference between components, rather than forming an azeotrope of differing volatility. The extractive agent and less volatile component flow to the bottoms of the distillation column, where the extracted component is recovered by a second subsequent distillation. The paper discusses this technology, mass transfer consideration, solvent selectivity, mixed solvent technology, testing and scale-up, and the use of this technology to remove aromatics from natural gas.

  1. Contact structure for use in catalytic distillation

    DOEpatents

    Jones, E.M. Jr.

    1984-03-27

    A method is described 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 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. 7 figs.

  2. Contact structure for use in catalytic distillation

    DOEpatents

    Jones, Jr., Edward M.

    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.

  3. Contact structure for use in catalytic distillation

    DOEpatents

    Jones, Jr., Edward M.

    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.

  4. Contact structure for use in catalytic distillation

    DOEpatents

    Jones, E.M. Jr.

    1985-08-20

    A method and apparatus are disclosed 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. 7 figs.

  5. Advanced Distillation Final Report

    SciTech Connect

    Maddalena Fanelli; Ravi Arora; Annalee Tonkovich; Jennifer Marco; Ed Rode

    2010-03-24

    The Advanced Distillation project was concluded on December 31, 2009. This U.S. Department of Energy (DOE) funded project was completed successfully and within budget during a timeline approved by DOE project managers, which included a one year extension to the initial ending date. The subject technology, Microchannel Process Technology (MPT) distillation, was expected to provide both capital and operating cost savings compared to conventional distillation technology. With efforts from Velocys and its project partners, MPT distillation was successfully demonstrated at a laboratory scale and its energy savings potential was calculated. While many objectives established at the beginning of the project were met, the project was only partially successful. At the conclusion, it appears that MPT distillation is not a good fit for the targeted separation of ethane and ethylene in large-scale ethylene production facilities, as greater advantages were seen for smaller scale distillations. Early in the project, work involved flowsheet analyses to discern the economic viability of ethane-ethylene MPT distillation and develop strategies for maximizing its impact on the economics of the process. This study confirmed that through modification to standard operating processes, MPT can enable net energy savings in excess of 20%. This advantage was used by ABB Lumus to determine the potential impact of MPT distillation on the ethane-ethylene market. The study indicated that a substantial market exists if the energy saving could be realized and if installed capital cost of MPT distillation was on par or less than conventional technology. Unfortunately, it was determined that the large number of MPT distillation units needed to perform ethane-ethylene separation for world-scale ethylene facilities, makes the targeted separation a poor fit for the technology in this application at the current state of manufacturing costs. Over the course of the project, distillation experiments were performed with the targeted mixture, ethane-ethylene, as well as with analogous low relative volatility systems: cyclohexane-hexane and cyclopentane-pentane. Devices and test stands were specifically designed for these efforts. Development progressed from experiments and models considering sections of a full scale device to the design, fabrication, and operation of a single-channel distillation unit with integrated heat transfer. Throughout the project, analytical and numerical models and Computational Fluid Dynamics (CFD) simulations were validated with experiments in the process of developing this platform technology. Experimental trials demonstrated steady and controllable distillation for a variety of process conditions. Values of Height-to-an-Equivalent Theoretical Plate (HETP) ranging from less than 0.5 inch to a few inches were experimentally proven, demonstrating a ten-fold performance enhancement relative to conventional distillation. This improvement, while substantial, is not sufficient for MPT distillation to displace very large scale distillation trains. Fortunately, parallel efforts in the area of business development have yielded other applications for MPT distillation, including smaller scale separations that benefit from the flowsheet flexibility offered by the technology. Talks with multiple potential partners are underway. Their outcome will also help determine the path ahead for MPT distillation.

  6. Datalogging the Distillation Process.

    ERIC Educational Resources Information Center

    Soares, Allan; Creevy, Steven

    1995-01-01

    Presents a distillation experiment that uses temperature sensors connected to a computer in place of thermometers, and enables the whole class to view the data on a monitor and interpret and discuss the data in real time. (JRH)

  7. Energy conservation in distillation

    NASA Astrophysics Data System (ADS)

    Mix, T. W.; Dweck, J. S.; Weinberg, M.; Armstrong, R. C.

    1981-07-01

    An audit of major industrial and processes and key colums in each major process indicated that approximately twoquads of energy were consumed for distillation in the US in 1976. Energy usage by industry is included: petroleum refineries, 66% chemical (including petrochemical) industry, 29% natural gas liquids processing, 5%. Techniques and current practices for conserving distillation energy are reviewed, and guidelines indicating those process conditons which favor the use of each energy conserving technique are enumerated. Expressions for payout time for tray and control retrofit options are developed based on energy savings and increased throughput. Calculations for industrial colums suggested that both types of retrofits would frequently have short (,6 months) payout times based on either criterion. Extractive distillation is also discussed, and criteria enabling the estimation of the energy which may be conserved using this technique are developed. Good housekeeping practices and field techniques for checking the energy efficiency of industrial distillations are also discussed.

  8. 19 CFR 11.6 - Distilled spirits, wines, and malt liquors in bulk.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...; DEPARTMENT OF THE TREASURY PACKING AND STAMPING; MARKING Packing and Stamping § 11.6 Distilled spirits, wines, and malt liquors in bulk. (a) The port director, in his discretion, may require marks, brands, stamps..., brands, stamps, labels, or similar devices required by Federal, State, or local statute or regulation...

  9. 19 CFR 11.6 - Distilled spirits, wines, and malt liquors in bulk.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...; DEPARTMENT OF THE TREASURY PACKING AND STAMPING; MARKING Packing and Stamping § 11.6 Distilled spirits, wines, and malt liquors in bulk. (a) The port director, in his discretion, may require marks, brands, stamps..., brands, stamps, labels, or similar devices required by Federal, State, or local statute or regulation...

  10. 19 CFR 11.6 - Distilled spirits, wines, and malt liquors in bulk.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...; DEPARTMENT OF THE TREASURY PACKING AND STAMPING; MARKING Packing and Stamping § 11.6 Distilled spirits, wines, and malt liquors in bulk. (a) The port director, in his discretion, may require marks, brands, stamps..., brands, stamps, labels, or similar devices required by Federal, State, or local statute or regulation...

  11. 19 CFR 11.6 - Distilled spirits, wines, and malt liquors in bulk.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...; DEPARTMENT OF THE TREASURY PACKING AND STAMPING; MARKING Packing and Stamping § 11.6 Distilled spirits, wines, and malt liquors in bulk. (a) The port director, in his discretion, may require marks, brands, stamps..., brands, stamps, labels, or similar devices required by Federal, State, or local statute or regulation...

  12. Rising groundwater tables in partly oxidized pyrite bearing dump-sediments: Column study and modelling approach

    NASA Astrophysics Data System (ADS)

    Kohfahl, Claus; Pekdeger, Asaf

    2006-12-01

    SummaryThis paper reports the hydrogeochemical modelling of reactions that take place during the uptake of weathering products by a rising watertable into a partly oxidized pyrite bearing sediment. The anoxic material used for the column, which is 2 m long, was taken from a core while drilling into a pyrite bearing sediment with an average pyrite content of 0.04 wt%. After packing the column it was drained and maintained in an unsaturated state over a period of 107 days to allow oxygen supply and pyrite weathering. During this period oxygen breakthrough curves were measured. After 108 days the column was flooded with distilled anoxic water from the bottom to the top with an average water table rise of 5 cm per day. The chemical composition of the pore water in the saturated zone as well as the water saturation and the oxygen contents have been monitored over the profile of the column. The compositions of the water samples at different depths of the column were modelled with PHREEQC, defining a one-dimensional reactive transport model regarding the mixing process between the incoming flooding water and the residual pore water of the drained period. Kinetic relations were implemented to account for source terms of acids and acid generating components released during the drained period. This study showed that the evolution of the rising water table can be characterized by almost immediate uptake of gypsum and by kinetically controlled dissolution of pyrite weathering products in combination with mixing processes and dispersion.

  13. Packing density of slurry-packed capillaries at low aspect ratios.

    PubMed

    Ehlert, Steffen; Rösler, Thomas; Tallarek, Ulrich

    2008-06-01

    The average interparticle voidage or porosity (epsilon(inter)) in cylindrical capillaries is studied in dependence on the column diameter (d(c)) to particle diameter (d(p)) ratio for 5 < d(c)/d(p) < 50. Using optimized slurry and packing solvents, high pressure and ultrasonication, 5 mum-sized porous C18-silica particles were slurry-packed into fused-silica capillaries having ids from 30 to 250 mum. Packing densities are assessed by a polystyrene standard which is size-excluded from the intraparticle pore space of the packings. For d(c)/d(p) > 35 densely packed beds are realized (epsilon(inter) = 0.36-0.37), while for decreasing aspect ratios an exponential increase in epsilon(inter )is observed reaching epsilon(inter ) approximately 0.47 at d(c)/d(p) = 5. This behaviour is ascribed to a combination of the geometrical wall effect operating in the direct vicinity of the column wall, caused by the inability of the particles to form a dense packing against the hard surface of the column wall, and particle characteristics like the size distribution, shape and surface roughness. Results are compared with the literature data to address also the importance of absolute particle size in studying structure-transport relations in packed beds in dependence on the aspect ratio d(c)/d(p). PMID:18481330

  14. 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.

  15. DISTILLATION OF CALCIUM

    DOEpatents

    Barton, J.

    1954-07-27

    This invention relates to an improvement in the process for the purification of caicium or magnesium containing an alkali metal as impurity, which comprises distiiling a batch of the mixture in two stages, the first stage distillation being carried out in the presence of an inert gas at an absolute pressure substantially greater than the vapor pressure of calcium or maguesium at the temperature of distillation, but less than the vaper pressure at that temperature of the alkali metal impurity so that only the alkali metal is vaporized and condensed on a condensing surface. A second stage distilso that substantially only the calcium or magnesium distills under its own vapor pressure only and condenses in solid form on a lower condensing surface.

  16. Distillation under electric fields

    SciTech Connect

    Shah, V.M.; Blankenship, K.D.; Tsouris, C.

    1997-11-01

    Distillation Is the most common separation process used in the chemical and petroleum industry. Major limitations in the applicability and efficiency of distillation come from thermodynamic equilibria, that is, vapor-liquid equilibria (VLE), and heat and mass transfer rates. In this work, electric fields are used to manipulate the VLE of mixtures. VLE experiments are performed for various binary mixtures in the presence of electric fields on the order of a few kilovolts per centimeter. The results show that the VLE is changed by electric fields, with changes in the separation factor as high as 10% being observed. Batch distillation experiments are also carried out for binary mixtures of 2-propanol and water with and without an applied electric field. Results show enhanced distillation rates and separation efficiency in the presence of an electric field but decreased separation enhancement when the electric current is increased. The latter phenomenon is caused by the formation at the surface of the liquid mixture of microdroplets that are entrained by the vapor. These observations suggest that there should be an electric field strength for each system for which the separation enhancement is maximum.

  17. Tritium Attenuation by Distillation

    SciTech Connect

    Wittman, N.E.

    2001-07-31

    The objective of this study was to determine how a 100 Area distillation system could be used to reduce to a satisfactory low value the tritium content of the dilute moderator produced in the 100 Area stills, and whether such a tritium attenuator would have sufficient capacity to process all this material before it is sent to the 400 Area for reprocessing.

  18. Dehydrate ethanol without distillation

    SciTech Connect

    Not Available

    1993-10-01

    Usina da Pedra (Serrana, state of Sao Paulo, Brazil) produces 60 million gal/yr of ethanol in 180 operating days. Until this year, the plant made 96 vol.% ethanol that is used as automotive fuel, and absolute ethanol (99.5 vol. %), which is blended with gasoline. Water is the remainder in both products. The ethanol is produced from the fermentation of sugar cane, and distilled with benzene. Benzene lowers the boiling point of the ethanol-water mixture and ties up the water. In May, Usina da Pedra installed a process that dehydrates ethanol by adsorption, not distillation. A vapor-phase process containing molecular sieves, handles throughputs as high as 160,000 acfh and has a maximum capacity of 70 million gal/yr. In addition to generating safer products, the energy savings gained by switching from distillation to adsorption are significant. The adsorptive system requires input of only 2,900 Btu per gallon of ethanol; one-third the energy consumed by distillation systems that employ benzene or cyclohexane.

  19. APPLICATION OF CAPILLARY SUPERCRITICAL FLUID CHROMATOGRAPHY TO THE ANALYSIS OF A MIDDLE DISTILLATE FUEL

    EPA Science Inventory

    The paper describes the application of capillary supercritical fluid chromatography (SFC) to the analysis of a middle distillate fuel. Small diameter (50 micrometer i.d.) fused silica capillary columns coated with crosslinked 50% phenyl polymethylsiloxane provided high separation...

  20. 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.

  1. 27 CFR 27.40 - Distilled spirits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... OF THE TREASURY LIQUORS IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER Tax On Imported Distilled Spirits, Wines, and Beer Distilled Spirits § 27.40 Distilled spirits. (a) A tax is imposed on...

  2. 27 CFR 27.40 - Distilled spirits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... OF THE TREASURY LIQUORS IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER Tax On Imported Distilled Spirits, Wines, and Beer Distilled Spirits § 27.40 Distilled spirits. (a) A tax is imposed on...

  3. 27 CFR 27.40 - Distilled spirits.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... OF THE TREASURY ALCOHOL IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER Tax On Imported Distilled Spirits, Wines, and Beer Distilled Spirits § 27.40 Distilled spirits. (a) A tax is imposed on...

  4. 27 CFR 27.40 - Distilled spirits.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... OF THE TREASURY ALCOHOL IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER Tax On Imported Distilled Spirits, Wines, and Beer Distilled Spirits § 27.40 Distilled spirits. (a) A tax is imposed on...

  5. 27 CFR 27.40 - Distilled spirits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... OF THE TREASURY LIQUORS IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER Tax On Imported Distilled Spirits, Wines, and Beer Distilled Spirits § 27.40 Distilled spirits. (a) A tax is imposed on...

  6. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

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

  7. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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

  8. Hydrocracking distillate feedstocks

    SciTech Connect

    Kurganov, V.M.; Gorshtein, A.B.; Shkol'nik, B.L.; Shtein, V.I.

    1987-05-01

    The main shortcoming of single-stage hydrocracking is the very high level of feedstock cracking. The authors discuss the development of multistage technology in which each stage can operate under optimal conditions at a moderate conversion level, better flexibility in process control, and better process indexes. The main feature of the multistage technology is the preliminary hydrogenation of the original feed. The composition of the original feed and the middle distillate cuts obtaining in two-stage hydrocracking of a vacuum distillate from West Siberian crude, using cobalt-molybdenum oxide catalyst in the first stage and a zeolitic catalyst in the second stage is presented. Data is provided on the influence of pressure on the hydrocracking indexes.

  9. Renormalizing Entanglement Distillation

    NASA Astrophysics Data System (ADS)

    Waeldchen, Stephan; Gertis, Janina; Campbell, Earl T.; Eisert, Jens

    2016-01-01

    Entanglement distillation refers to the task of transforming a collection of weakly entangled pairs into fewer highly entangled ones. It is a core ingredient in quantum repeater protocols, which are needed to transmit entanglement over arbitrary distances in order to realize quantum key distribution schemes. Usually, it is assumed that the initial entangled pairs are identically and independently distributed and are uncorrelated with each other, an assumption that might not be reasonable at all in any entanglement generation process involving memory channels. Here, we introduce a framework that captures entanglement distillation in the presence of natural correlations arising from memory channels. Conceptually, we bring together ideas from condensed-matter physics—ideas from renormalization and matrix-product states and operators—with those of local entanglement manipulation, Markov chain mixing, and quantum error correction. We identify meaningful parameter regions for which we prove convergence to maximally entangled states, arising as the fixed points of a matrix-product operator renormalization flow.

  10. Cascade Distillation System Development

    NASA Technical Reports Server (NTRS)

    Callahan, Michael R.; Sargushingh, Miriam; Shull, Sarah

    2014-01-01

    NASA's Advanced Exploration Systems (AES) Life Support System (LSS) Project is chartered with de-veloping advanced life support systems that will ena-ble NASA human exploration beyond low Earth orbit (LEO). The goal of AES is to increase the affordabil-ity of long-duration life support missions, and to re-duce the risk associated with integrating and infusing new enabling technologies required to ensure mission success. Because of the robust nature of distillation systems, the AES LSS Project is pursuing develop-ment of the Cascade Distillation Subsystem (CDS) as part of its technology portfolio. Currently, the system is being developed into a flight forward Generation 2.0 design.

  11. Stationary Apollonian Packings

    NASA Astrophysics Data System (ADS)

    Hirsch, Christian; Delaney, Gary; Schmidt, Volker

    2015-10-01

    The notion of stationary Apollonian packings in the d-dimensional Euclidean space is introduced as a mathematical formalization of so-called random Apollonian packings and rotational random Apollonian packings, which constitute popular grain packing models in physics. Apart from dealing with issues of existence and uniqueness in the entire Euclidean space, asymptotic results are provided for the growth durations and it is shown that the packing is space-filling with probability 1, in the sense that the Lebesgue measure of its complement is zero. Finally, the phenomenon is studied that grains arrange in clusters and properties related to percolation are investigated.

  12. Self-regenerating column chromatography

    SciTech Connect

    Park, Woo K.

    1995-05-30

    The present invention provides a process for treating both cations and anions by using a self-regenerating, multi-ionic exchange resin column system which requires no separate regeneration steps. The process involves alternating ion-exchange chromatography for cations and anions in a multi-ionic exchange column packed with a mixture of cation and anion exchange resins. The multi-ionic mixed-charge resin column works as a multi-function column, capable of independently processing either cationic or anionic exchange, or simultaneously processing both cationic and anionic exchanges. The major advantage offered by the alternating multi-function ion exchange process is the self-regeneration of the resins.

  13. A heat & mass integration approach to reduce capital and operating costs of a distillation configuration

    SciTech Connect

    Madenoor Ramapriya, Gautham; Jiang, Zheyu; Tawarmalani, Mohit; Agrawal, Rakesh

    2015-11-11

    We propose a general method to consolidate distillation columns of a distillation configuration using heat and mass integration. The proposed method encompasses all heat and mass integrations known till date, and includes many more. Each heat and mass integration eliminates a distillation column, a condenser, a reboiler and the heat duty associated with a reboiler. Thus, heat and mass integration can potentially offer significant capital and operating cost benefits. In this talk, we will study the various possible heat and mass integrations in detail, and demonstrate their benefits using case studies. This work will lay out a framework to synthesize an entire new class of useful configurations based on heat and mass integration of distillation columns.

  14. Biomass growth restriction in a packed bed reactor

    DOEpatents

    Griffith, William L.; Compere, Alicia L.

    1978-01-01

    When carrying out continuous biologically catalyzed reactions with anaerobic microorganisms attached to a support in an upflow packed bed column, growth of the microorganisms is restricted to prevent the microorganisms from plugging the column by limiting the availability of an essential nutrient and/or by the presence of predatory protozoa which consume the anaerobic microorganisms. A membrane disruptive detergent may be provided in the column to lyse dead microorganisms to make them available as nutrients for live microorganisms.

  15. Solar distillation apparatus

    SciTech Connect

    Snyder, W.L.

    1981-06-30

    A solar distillation unit is disclosed capable of operating entirely off solar radiation and intended for large scale industrial use offshore. A lens focusing system housed within an enclosed shell focuses the incident radiation from the sun on a heating element. Saltwater or contaminated fresh water is ejected toward the heating element at a predetermined rate resulting in the immediate evaporation of the water. The water vapor migrates and condenses on the cooler inner surface of the shell running to the bottom where it is collected and removed as fresh water.

  16. 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.

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

    DOEpatents

    Springston, Stephen R.

    1990-01-01

    A method 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.

  18. Retractable packings pass inspection

    SciTech Connect

    Cerasoli, D.J. )

    1992-06-01

    This paper reports on retractable packing which has proved to be a popular preventive fix for the problem of packing seal wear on aging steam turbines. Designed to eliminate the excessive wear that occurs during start-up from thermal distortion and vibration, retractable packing employs coil springs that force it open to a 150-mil clearance until increasing steam flow forces it closed to design clearance. Utilities have reported performance improvements after installation of Brandon retractable packing. Although it is recognized that all performance gains where not solely a result of the packing-minor repairs were also performed to correct losses due to erosion, deposits and mechanical damage-initial results indicated the packing was performing as expected.

  19. Renormalizing Entanglement Distillation.

    PubMed

    Waeldchen, Stephan; Gertis, Janina; Campbell, Earl T; Eisert, Jens

    2016-01-15

    Entanglement distillation refers to the task of transforming a collection of weakly entangled pairs into fewer highly entangled ones. It is a core ingredient in quantum repeater protocols, which are needed to transmit entanglement over arbitrary distances in order to realize quantum key distribution schemes. Usually, it is assumed that the initial entangled pairs are identically and independently distributed and are uncorrelated with each other, an assumption that might not be reasonable at all in any entanglement generation process involving memory channels. Here, we introduce a framework that captures entanglement distillation in the presence of natural correlations arising from memory channels. Conceptually, we bring together ideas from condensed-matter physics-ideas from renormalization and matrix-product states and operators-with those of local entanglement manipulation, Markov chain mixing, and quantum error correction. We identify meaningful parameter regions for which we prove convergence to maximally entangled states, arising as the fixed points of a matrix-product operator renormalization flow. PMID:26824532

  20. Electronically configured battery pack

    SciTech Connect

    Kemper, D.

    1997-03-01

    Battery packs for portable equipment must sometimes accommodate conflicting requirements to meet application needs. An electronically configurable battery pack was developed to support two highly different operating modes, one requiring very low power consumption at a low voltage and the other requiring high power consumption at a higher voltage. The configurable battery pack optimizes the lifetime and performance of the system by making the best use of all available energy thus enabling the system to meet its goals of operation, volume, and lifetime. This paper describes the cell chemistry chosen, the battery pack electronics, and tradeoffs made during the evolution of its design.

  1. Systems and methods for reactive distillation with recirculation of light components

    DOEpatents

    Stickney, Michael J.; Jones, Jr., Edward M.

    2011-07-26

    Systems and methods for producing gas-to-liquids products using reactive distillation are provided. The method for producing gas-to-liquids products can include reacting a feedstock in a column having a distillation zone and a reaction zone to provide a bottoms stream and an overhead stream. A first portion of the overhead stream can be recycled to the column at the top of the reaction zone and second portion of the overhead stream can be recycled to the column at the bottom of the reaction zone.

  2. 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.

  3. TLC Pack Unpacked

    ERIC Educational Resources Information Center

    Oberhofer, Margret; Colpaert, Jozef

    2015-01-01

    TLC Pack stands for Teaching Languages to Caregivers and is a course designed to support migrants working or hoping to work in the caregiving sector. The TLC Pack resources range from A2 to B2 level of the Common European Framework of Reference for Languages (CEFR), and will be made available online in the six project languages: Dutch, English,…

  4. Career Action Pack.

    ERIC Educational Resources Information Center

    Blum, Robert E.; Raymond, Carolyn D.

    One of five McDonald's Action Packs, these instructional materials for ninth and tenth graders (and more able sixth and seventh graders) have incorporated ideas around three career development goals--subject relevance, career awareness, and self-awareness. The action pack contains six units--three units each in the subject areas of language arts…

  5. Flat Pack Toy Design

    ERIC Educational Resources Information Center

    Hutcheson, Brian

    2007-01-01

    In this article, the author introduces the concept of flat pack toys. Flat pack toys are designed using a template on a single sheet of letter-sized card stock paper. Before being cut out and built into a three-dimensional toy, they are scanned into the computer and uploaded to a website. With the template accessible from the website, anyone with…

  6. Flat Pack Toy Design

    ERIC Educational Resources Information Center

    Hutcheson, Brian

    2007-01-01

    In this article, the author introduces the concept of flat pack toys. Flat pack toys are designed using a template on a single sheet of letter-sized card stock paper. Before being cut out and built into a three-dimensional toy, they are scanned into the computer and uploaded to a website. With the template accessible from the website, anyone with

  7. The role of ionic strength and grain size on the transport of colloids in unsaturated sand columns

    NASA Astrophysics Data System (ADS)

    Mitropoulou, Polyxeni N.; Syngouna, Vasiliki I.; Chrysikopoulos, Constantinos V.

    2013-04-01

    The main objective of this study was to better understand the combined effects of ionic strength, and sand grain size on colloid fate and transport in unsaturated porous media. Spherical fluorescent polymer microspheres with three different sizes (0.075, 0.30 and 2.1 μm), and laboratory columns packed with two size fractions of clean quartz sand (0.513 and 0.181 mm) were used. The saturation level of the packed columns was set to 83-95% with solutions having a wide range of ionic strength (0.1-1000 mM). The electrophoretic mobility of colloids and sand grains were evaluated for all the experimental conditions employed. The various experimental collision efficiencies were quantified using the classical colloid filtration theory. The theoretical collision efficiencies were estimated with appropriate DLVO energies using a Maxwell model. The experimental results suggested that the retention of the bigger colloids (2.1 μm) was slightly higher compared to the conservative tracer and smaller colloids (0.3 and 0.075 μm) in deionized-distilled-water, indicating sorption at air-water interfaces or straining. Moreover, relatively smaller attachment was observed onto fine than medium quartz sand. The mass recovery of the 0.3 μm microspheres in NaCl solution was shown to significantly decrease with increasing ionic strength. Both the experimental and theoretical collision efficiencies based on colloid interactions with solid-water interfaces, were increased with increasing ionic strength.

  8. Graphitic packing removal tool

    DOEpatents

    Meyers, Kurt Edward; Kolsun, George J.

    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.

  9. Graphitic packing removal tool

    DOEpatents

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

    1997-11-11

    Graphitic packing removal tools for removal of the seal rings in one piece are disclosed. 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. 5 figs.

  10. 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.

  11. 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

  12. Contexts for Column Addition and Subtraction

    ERIC Educational Resources Information Center

    Lopez Fernandez, Jorge M.; Velazquez Estrella, Aileen

    2011-01-01

    In this article, the authors discuss their approach to column addition and subtraction algorithms. Adapting an original idea of Paul Cobb and Erna Yackel's from "A Contextual Investigation of Three-Digit Addition and Subtraction" related to packing and unpacking candy in a candy factory, the authors provided an analogous context by designing…

  13. Distillation process using microchannel technology

    DOEpatents

    Tonkovich, Anna Lee; Simmons, Wayne W.; Silva, Laura J.; Qiu, Dongming; Perry, Steven T.; Yuschak, Thomas; Hickey, Thomas P.; Arora, Ravi; Smith, Amanda; Litt, Robert Dwayne; Neagle, Paul

    2009-11-03

    The disclosed invention relates to a distillation process for separating two or more components having different volatilities from a liquid mixture containing the components. The process employs microchannel technology for effecting the distillation and is particularly suitable for conducting difficult separations, such as the separation of ethane from ethylene, wherein the individual components are characterized by having volatilities that are very close to one another.

  14. Shell's Middle Distillate Synthesis process

    SciTech Connect

    Voetter, H.; VanDerBurgt, M.J. B.V., The Hague )

    1988-01-01

    The basis of the Shell Middle Distillate Synthesis (SMDS) process is the classic Fischer-Tropsch synthesis. For the case of middle distillate production from natural gas the procedure has been developed to commercial maturity, making use of tailored line-up for synthesis gas production and of proprietary modern catalysts in synthesis. Development work over the last years has in particular lead to improvement of the economy of the process altogether via catalyst performance, reactor sizing and syngas manufacturing line-up.

  15. Zirconium and hafnium tetrachloride separation by extractive distillation with molten zinc chloride lead chloride solvent

    SciTech Connect

    McLaughlin, D.F.; Stoltz, R.A.

    1988-04-12

    In an extractive distillation method for separating hafniuim tetrachloride from zirconium tetrachloride of the type wherein a mixture of zirconium and hafnium tetrachlorides is introduced into an extractive distillation column, which extractive distillation column has a reboiler connected at the bottom and a reflux condenser connected at the top and wherein a molten salt solvent is circulated into the reflux condenser and through the column to provide a liquid phase, and wherein molten salt solvent containing zirconium tetrachloride is taken from the reboiler and run through a stripper to remove zirconium tetrachloride product from the molten salt solvent and the stripped molten salt solvent is returned to the reflux condenser and hafnium tetrachloride enriched vapor is taken as product from the reflux condenser, the improvement is described comprising: the molten salt having a composition of at least 30 mole percent zinc chloride and at least 10 mole percent of lead chloride.

  16. Experimental investigation on hydrogen cryogenic distillation equipped with package made by ICIT

    SciTech Connect

    Bornea, A.; Zamfirache, M.; Stefan, L.; Stefanescu, I.; Preda, A.

    2015-03-15

    ICIT (Institute for Cryogenics and Isotopic Technologies) has used its experience in cryogenic water distillation process to propose a similar process for hydrogen distillation that can be used in detritiation technologies. This process relies on the same packages but a stainless filling is tested instead of the phosphorous bronze filling used for water distillation. This paper presents two types of packages developed for hydrogen distillation, both have a stainless filling but it differs in terms of density, exchange surface and specific volume. Performance data have been obtained on laboratory scale. In order to determine the characteristics of the package, the installation was operated in the total reflux mode, for different flow rate for the liquid. There were made several experiments considering different operating conditions. Samples extracted at the top and bottom of cryogenic distillation column allowed mathematical processing to determine the separation performance. The experiments show a better efficiency for the package whose exchange surface was higher and there were no relevant differences between both packages as the operating pressure of the cryogenic column was increasing. For a complete characterization of the packages, future experiments will be considered to determine performance at various velocities in the column and their correlation with the pressure in the column. We plan further experiments to separate tritium from the mixture of isotopes DT, having in view that our goal is to apply this results to a detritiation plant.

  17. DESIGN SCALE-UP SUITABILITY FOR AIR-STRIPPING COLUMNS

    EPA Science Inventory

    Air-stripping in a packed column is sometimes used to remove volatile organic compounds from contaminated water supplies. Since the design engineer frequently uses data from a pilot air-stripping column to design a full-scale system, the suitability of such design scale-up was in...

  18. Theory of random packings

    NASA Astrophysics Data System (ADS)

    Song, Chaoming; Wang, Ping; Makse, Hernán A.

    2010-05-01

    We review a recently proposed theory of random packings. We describe the volume fluctuations in jammed matter through a volume function, amenable to analytical and numerical calculations. We combine an extended statistical mechanics approach `a la Edwards' (where the role traditionally played by the energy and temperature in thermal systems is substituted by the volume and compactivity) with a constraint on mechanical stability imposed by the isostatic condition. We show how such approaches can bring results that can be compared to experiments and allow for an exploitation of the statistical mechanics framework. The key result is the use of a relation between the local Voronoi volume of the constituent grains and the number of neighbors in contact that permits a simple combination of the two approaches to develop a theory of random packings. We predict the density of random loose packing (RLP) and random close packing (RCP) in close agreement with experiments and develop a phase diagram of jammed matter that provides a unifying view of the disordered hard sphere packing problem and further shedding light on a diverse spectrum of data, including the RLP state. Theoretical results are well reproduced by numerical simulations that confirm the essential role played by friction in determining both the RLP and RCP limits. Finally we present an extended discussion on the existence of geometrical and mechanical coordination numbers and how to measure both quantities in experiments and computer simulations.

  19. Non-planar microfabricated gas chromatography column

    DOEpatents

    Lewis, Patrick R.; Wheeler, David R.

    2007-09-25

    A non-planar microfabricated gas chromatography column comprises a planar substrate having a plurality of through holes, a top lid and a bottom lid bonded to opposite surfaces of the planar substrate, and inlet and outlet ports for injection of a sample gas and elution of separated analytes. A plurality of such planar substrates can be aligned and stacked to provide a longer column length having a small footprint. Furthermore, two or more separate channels can enable multi-channel or multi-dimensional gas chromatography. The through holes preferably have a circular cross section and can be coated with a stationary phase material or packed with a porous packing material. Importantly, uniform stationary phase coatings can be obtained and band broadening can be minimized with the circular channels. A heating or cooling element can be disposed on at least one of the lids to enable temperature programming of the column.

  20. Determination of fluconazole by direct injection of plasma and high performance liquid chromatography with column switching.

    PubMed

    Li, Z W; Guo, P; Ye, L M; Hong, Z; Wang, Y S

    1994-01-01

    High performance liquid chromatography with column switching has been developed for the determination of fluconazole in plasma. The plasma samples were injected onto a precolumn packed with LiChromprep RP2(25-40 microns) after simple dilution with a solution of 0.2 mol.L-1 acetic acid. Distilled water was used to wash out protein and other polar components in plasma. After switching, the concentrated fluconazole was eluted in the back-flush mode onto a Shimpack CLC-ODS column with methanol--0.2 mol.L-1 ammonium acetate (pH 2.7) (50:50) as mobile phase. Purge solutions were used for clean-up and for regenerating the precolumn. The method showed a good precision and excellent recovery. The detection limit was 0.12 micrograms.ml-1 plasma. The RSD's (intra- and interday) were less than 6.3%. The method has been successfully used to determine bioavailability and pharmacokinetics of fluconazole in Chinese volunteers. PMID:7871997

  1. Suspension column for recovery and separation of substances using ultrasound-assisted retention of bead sorbents.

    PubMed

    Spivakov, Boris Ya; Shkinev, Valeriy M; Danilova, Tatiana V; Knyazkov, Nikolai N; Kurochkin, Vladimir E; Karandashev, Vasiliy K

    2012-12-15

    A novel approach to sorption recovery and separation of different substances is proposed which is based on the use of suspended bead sorbents instead of conventional packed beds of such sorbents. This makes it possible to employ small-sized beads which are trapped in a low-pressure column due to ultrasound-assisted retention, without any frits to hold the sorption material. A flow system including a separation mini-column, named herein a suspension column, has been developed and tested by the studies of solid phase extraction (SPE) of trace metals from bi-distilled water and sea water using a 150-μL column with a silica-based sorbent containing iminodiacetic groups (DIAPAK IDA) and having a grain size of 6 μm. The adsorption properties of DIAPAK IDA suspension (9.5mg) were evaluated through adsorption/desorption experiments, where the effect of solution pH and eluent on the SPE of trace metals were examined by ICP-MS or ICP-AES measurements. When sample solution was adjusted to pH 8.0 and 1 mol L(-1) nitric acid was used as eluent, very good recoveries of more than 90% were obtained for a number of elements in a single-step extraction. To demonstrate the versatility of the approach proposed and to show another advantage of ultrasonic field (acceleration of sorbate/sorbent interaction), a similar system was used for heterogeneous immunoassays of some antigens in ultrasonic field using agarose sorbents modified by corresponding antibodies. It has been shown that immunoglobulins, chlamidia, and brucellos bacteria can be quantitatively adsorbed on 15-μm sorbent (15 particles in 50 μL) and directly determined in a 50-μL mini-chamber using fluorescence detection. PMID:23182579

  2. 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.

  3. Distillation and Air Stripping Designs for the Lunar Surface

    NASA Technical Reports Server (NTRS)

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

    2009-01-01

    Air stripping and distillation are two different gravity-based methods, which may be applied to the purification of wastewater on the lunar base. These gravity-based solutions to water processing are robust physical separation techniques, which may be advantageous to many other techniques for their simplicity in design and operation. The two techniques can be used in conjunction with each other to obtain high purity water. The components and feed compositions for modeling waste water streams are presented in conjunction with the Aspen property system for traditional stage distillation models and air stripping models. While the individual components for each of the waste streams will vary naturally within certain bounds, an analog model for waste water processing is suggested based on typical concentration ranges for these components. Target purity levels for the for recycled water are determined for each individual component based on NASA s required maximum contaminant levels for potable water Distillation processes are modeled separately and in tandem with air stripping to demonstrate the potential effectiveness and utility of these methods in recycling wastewater on the Moon. Optimum parameters such as reflux ratio, feed stage location, and processing rates are determined with respect to the power consumption of the process. Multistage distillation is evaluated for components in wastewater to determine the minimum number of stages necessary for each of 65 components in humidity condensate and urine wastewater mixed streams. Components of the wastewater streams are ranked by Henry s Law Constant and the suitability of air stripping in the purification of wastewater in terms of component removal is evaluated. Scaling factors for distillation and air stripping columns are presented to account for the difference in the lunar gravitation environment. Commercially available distillation and air stripping units which are considered suitable for Exploration Life Support are presented. The advantages to the various designs are summarized with respect to water purity levels, power consumption, and processing rates.

  4. Mass transfer model liquid phase catalytic exchange column simulation applicable to any column composition profile

    SciTech Connect

    Busigin, A.

    2015-03-15

    Liquid Phase Catalytic Exchange (LPCE) is a key technology used in water detritiation systems. Rigorous simulation of LPCE is complicated when a column may have both hydrogen and deuterium present in significant concentrations in different sections of the column. This paper presents a general mass transfer model for a homogenous packed bed LPCE column as a set of differential equations describing composition change, and equilibrium equations to define the mass transfer driving force within the column. The model is used to show the effect of deuterium buildup in the bottom of an LPCE column from non-negligible D atom fraction in the bottom feed gas to the column. These types of calculations are important in the design of CECE (Combined Electrolysis and Catalytic Exchange) water detritiation systems.

  5. Comparison of advanced distillation control methods. Third annual report

    SciTech Connect

    Riggs, J.B.

    1997-07-01

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to study the issue of configuration selection for diagonal PI dual composition controls, feedforward from a feed composition analyzer, and decouplers. Auto Tune Variation (ATV) identification with on-line detuning for setpoint changes was used for tuning the diagonal proportional integral (PI) composition controls. In addition, robustness tests were conducted by inducting reboiler duty upsets. For single composition control, the (L, V) configuration was found to be best. For dual composition control, the optimum configuration changes from one column to another. Moreover, the use of analysis tools, such as RGA, appears to be of little value in identifying the optimum configuration for dual composition control. Using feedforward from a feed composition analyzer and using decouplers are shown to offer significant advantages for certain specific cases.

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

  7. Bulk stress distributions in the pore space of sphere-packed beds under Darcy flow conditions.

    PubMed

    Pham, Ngoc H; Voronov, Roman S; Tummala, Naga Rajesh; Papavassiliou, Dimitrios V

    2014-03-01

    In this paper, bulk stress distributions in the pore space of columns packed with spheres are numerically computed with lattice Boltzmann simulations. Three different ideally packed and one randomly packed configuration of the columns are considered under Darcy flow conditions. The stress distributions change when the packing type changes. In the Darcy regime, the normalized stress distribution for a particular packing type is independent of the pressure difference that drives the flow and presents a common pattern. The three parameter (3P) log-normal distribution is found to describe the stress distributions in the randomly packed beds within statistical accuracy. In addition, the 3P log-normal distribution is still valid when highly porous scaffold geometries rather than sphere beds are examined. It is also shown that the 3P log-normal distribution can describe the bulk stress distribution in consolidated reservoir rocks like Berea sandstone. PMID:24730946

  8. Bulk stress distributions in the pore space of sphere-packed beds under Darcy flow conditions

    NASA Astrophysics Data System (ADS)

    Pham, Ngoc H.; Voronov, Roman S.; Tummala, Naga Rajesh; Papavassiliou, Dimitrios V.

    2014-03-01

    In this paper, bulk stress distributions in the pore space of columns packed with spheres are numerically computed with lattice Boltzmann simulations. Three different ideally packed and one randomly packed configuration of the columns are considered under Darcy flow conditions. The stress distributions change when the packing type changes. In the Darcy regime, the normalized stress distribution for a particular packing type is independent of the pressure difference that drives the flow and presents a common pattern. The three parameter (3P) log-normal distribution is found to describe the stress distributions in the randomly packed beds within statistical accuracy. In addition, the 3P log-normal distribution is still valid when highly porous scaffold geometries rather than sphere beds are examined. It is also shown that the 3P log-normal distribution can describe the bulk stress distribution in consolidated reservoir rocks like Berea sandstone.

  9. 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.

  10. Optimal protocols for nonlocality distillation

    SciTech Connect

    Hoeyer, Peter; Rashid, Jibran

    2010-10-15

    Forster et al. recently showed that weak nonlocality can be amplified by giving the first protocol that distills a class of nonlocal boxes (NLBs) [Phys. Rev. Lett. 102, 120401 (2009)] We first show that their protocol is optimal among all nonadaptive protocols. We next consider adaptive protocols. We show that the depth-2 protocol of Allcock et al. [Phys. Rev. A 80, 062107 (2009)] performs better than previously known adaptive depth-2 protocols for all symmetric NLBs. We present a depth-3 protocol that extends the known region of distillable NLBs. We give examples of NLBs for which each of the Forster et al., the Allcock et al., and our protocols perform best. The understanding we develop is that there is no single optimal protocol for NLB distillation. The choice of which protocol to use depends on the noise parameters for the NLB.

  11. 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,…

  12. 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)

  13. AUTOmatic Message PACKing Facility

    Energy Science and Technology Software Center (ESTSC)

    2004-07-01

    AUTOPACK is a library that provides several useful features for programs using the Message Passing Interface (MPI). Features included are: 1. automatic message packing facility 2. management of send and receive requests. 3. management of message buffer memory. 4. determination of the number of anticipated messages from a set of arbitrary sends, and 5. deterministic message delivery for testing purposes.

  14. 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].

  15. Quality improvements of cell membrane chromatographic column.

    PubMed

    Ding, Xuan; Chen, Xiaofei; Cao, Yan; Jia, Dan; Wang, Dongyao; Zhu, Zhenyu; Zhang, Juping; Hong, Zhanying; Chai, Yifeng

    2014-09-12

    Cell Membrane Chromatography (CMC) is a biological affinity chromatographic method using a silica stationary phase covered with specific cell membrane. However, its short life span and poor quality control was highlighted in a lot of research articles. In this study, special attention has been paid to the disruption, cell load and packing procedure in order to improve the quality of the CMC columns. Hereto, two newly established CMC models, HSC-T6/CMC and SMMC-7721/CMC have been developed and used in this research project. The optimization of the abovementioned parameters resulted in a better reproducibility of the retention time of the compound GFT (RSD<10%) and improved significantly the quality of the CMC columns. 3.5×10(7)cells were the optimal cell load for the preparation of the CMC columns, the disruption condition was optimized to 5 cycles (400W and 20s interval per cycle) by an ultrasonic processor reducing the total time of cell disruption to 1.5min and the packing flow rate was optimized by applying a linear gradient program. Additionally, 4% paraformaldehyde (PFA) was employed to improve the column quality and prolong the column life span. The results showed that the retention time was longer with PFA treated columns than the ones obtained with the control groups. PMID:25115453

  16. Extended testing of compression distillation.

    NASA Technical Reports Server (NTRS)

    Bambenek, R. A.; Nuccio, P. P.

    1972-01-01

    During the past eight years, the NASA Manned Spacecraft Center has supported the development of an integrated water and waste management system which includes the compression distillation process for recovering useable water from urine, urinal flush water, humidity condensate, commode flush water, and concentrated wash water. This paper describes the design of the compression distillation unit, developed for this system, and the testing performed to demonstrate its reliability and performance. In addition, this paper summarizes the work performed on pretreatment and post-treatment processes, to assure the recovery of sterile potable water from urine and treated urinal flush water.

  17. Bounds for nonlocality distillation protocols

    SciTech Connect

    Forster, Manuel

    2011-06-15

    Nonlocality can be quantified by the violation of a Bell inequality. Since this violation may be amplified by local operations, an alternative measure has been proposed--distillable nonlocality. The alternative measure is difficult to calculate exactly due to the double exponential growth of the parameter space. In this paper, we give a way to bound the distillable nonlocality of a resource by the solutions to a related optimization problem. Our upper bounds are exponentially easier to compute than the exact value and are shown to be meaningful in general and tight in some cases.

  18. Purifying Aluminum by Vacuum Distillation

    NASA Technical Reports Server (NTRS)

    Du Fresne, E. R.

    1985-01-01

    Proposed method for purifying aluminum employs one-step vacuum distillation. Raw material for process impure aluminum produced in electrolysis of aluminum ore. Impure metal melted in vacuum. Since aluminum has much higher vapor pressure than other constituents, boils off and condenses on nearby cold surfaces in proportions much greater than those of other constituents.

  19. Corrosion inhibition for distillation apparatus

    DOEpatents

    Baumert, Kenneth L.; Sagues, Alberto A.; Davis, Burtron H.; Schweighardt, Frank K.

    1985-01-01

    Tower material corrosion in an atmospheric or sub-atmospheric distillation tower in a coal liquefaction process is reduced or eliminated by subjecting chloride-containing tray contents to an appropriate ion-exchange resin to remove chloride from such tray contents materials.

  20. Properties of Distillers Grains Composites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest in renewable biofuel sources has intensified in recent years, leading to greatly increased production of ethanol and its primary coproduct, Distillers Dried Grain with Solubles (DDGS). Consequently, the development of new outlets for DDGS has become crucial to maintaining the economic viab...

  1. Entanglement preservation by continuous distillation

    SciTech Connect

    Mundarain, D.; Orszag, M.

    2009-05-15

    We study the two-qubit entanglement preservation for a system in the presence of independent thermal baths. We use a combination of filtering operations and distillation protocols as a series of frequent measurements on the system. It is shown that a small fraction of the total amount of available copies of the system preserves or even improves its initial entanglement during the evolution.

  2. Plant transpiration distillation of water

    SciTech Connect

    Virostko, M.K.; Spielberg, J.I.

    1986-01-01

    A project using solar energy and the transpiration of plants for the distillation of water is described. Along with determining which of three plants thrived best growing in a still, the experiment also revealed that the still functioned nearly as well in inclement weather as in fair weather.

  3. Low Temperature Distillation for Desalination

    NASA Astrophysics Data System (ADS)

    Schultz, William

    2013-11-01

    We examine a unique configuration that combines the evaporator and condenser in a low temperature distillation process. The low temperature (pressure) container is designed to use waste heat from a power plant as the hot source and a water reservoir as the cold source. Fresh and saline streams of droplets in close proximity create interesting hydrodynamic challenges for the directional stability of the droplets.

  4. Nonlinear control of a multicomponent distillation process coupled with a binary distillation model as an EKF predictor.

    PubMed

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

    2006-10-01

    The work is devoted to design the globally linearizing control (GLC) strategy for a multicomponent distillation process. The control system is comprised with a nonlinear transformer, a nonlinear closed-loop state estimator [extended Kalman filter (EKF)], and a linear external controller [conventional proportional integral (PI) controller]. The model of a binary distillation column has been used as a state predictor to avoid huge design complexity of the EKF estimator. The binary components are the light key and the heavy key of the multicomponent system. The proposed GLC-EKF (GLC in conjunction with EKF) control algorithm has been compared with the GLC-ROOLE [GLC coupled with reduced-order open-loop estimator (ROOLE)] and the dual-loop PI controller based on set point tracking and disturbance rejection performance. Despite huge process/predictor mismatch, the superiority of the GLC-EKF has been inspected over the GLC-ROOLE control structure. PMID:17063939

  5. Radial heterogeneity of some analytical columns used in high-performance liquid chromatography

    SciTech Connect

    Mriziq, Khaled S; Guiochon, Georges A

    2009-01-01

    An on-column electrochemical microdetector was used to determine accurately the radial distribution of the mobile phase velocity and of the column efficiency at the exit of three common analytical columns, namely a 100 mm x 4.6 mm C18 bonded silica-based monolithic column, a 150 mm x 4.6 mm column packed with 2.7 {micro}m porous shell particles of C18 bonded silica (HALO), and a 150 mm x 4.6 mm column packed with 3 {micro}m fully porous C18 bonded silica particles (LUNA). The results obtained demonstrate that all three columns are not radially homogeneous. In all three cases, the efficiency was found to be lower in the wall region of the column than in its core region (the central core with a radius of 1/3 the column inner radius). The decrease in local efficiency from the core to the wall regions was lower in the case of the monolith (ca. 25%) than in that of the two particle-packed columns (ca. 35-50%). The mobile phase velocity was found to be ca. 1.5% higher in the wall than in the core region of the monolithic column while, in contrast, it was ca. 2.5-4.0% lower in the wall region for the two particle-packed columns.

  6. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Distilling material. 24..., DEPARTMENT OF THE TREASURY ALCOHOL WINE Production of Other Than Standard Wine § 24.216 Distilling material... fruit residues, for use as distilling material, using any quantity of water desired to...

  7. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Distilling material. 24.216 Section 24.216 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... fermentation or distillation. No sugar may be added in the production of distilling material....

  8. 27 CFR 19.301 - Distillation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Distillation. 19.301 Section 19.301 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... of Spirits § 19.301 Distillation. The distillation of spirits must be done in a continuous...

  9. 27 CFR 19.301 - Distillation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Distillation. 19.301 Section 19.301 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... of Spirits § 19.301 Distillation. The distillation of spirits must be done in a continuous...

  10. 27 CFR 19.301 - Distillation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Distillation. 19.301 Section 19.301 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... of Spirits § 19.301 Distillation. The distillation of spirits must be done in a continuous...

  11. 27 CFR 19.301 - Distillation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Distillation. 19.301 Section 19.301 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... of Spirits § 19.301 Distillation. The distillation of spirits must be done in a continuous...

  12. Real-time monitoring of distillations by near-infrared spectroscopy.

    PubMed

    Pasquini, Celio; Scafi, Sérgio H F

    2003-05-15

    A simple device is described to couple a fast-scanning acoustooptic tunable filter-based NIR spectrophotometer to a distillation apparatus for monitoring the condensed vapor in real time. The device consists of a small funnel whose glass neck (2-mm diameter) is bent into an "U" format to produce a flow cell of approximately 150-microL inner volume. A pair of optical fibers is used to deliver the monochromatic light and to collect the fraction passing through the glass tube. The end of the condenser of the distillation head touches the wall of the small funnel. The condensed liquid flows uncoupled from pressure changes in the interior of the distillation head. Absorbance spectra were obtained, during the distillation, as averages of 50 scans (4 s) every 5 s in the spectral range 950-1800 nm with nominal resolution of 2.0 nm. In the first experiments, the distillations were performed at constant power supplied to the sample (25 mL) in a microdistillation apparatus working without any type of reflux column. The usefulness of the real-time monitoring of distillation is demonstrated using some prepared binary mixtures and by comparing the distillation behavior of adulterated and regular gasoline samples. Data analysis and interpretation are facilitated by employing principal component analysis. The system accesses the composition of the condensate, which can separate and concentrate one or more compounds present in the original sample. PMID:12918966

  13. Cascade Distillation Subsystem Development: Progress Toward a Distillation Comparison Test

    NASA Technical Reports Server (NTRS)

    Callahan, M. R.; Lubman, A.; Pickering, Karen D.

    2009-01-01

    Recovery of potable water from wastewater is essential for the success of long-duration manned missions to the Moon and Mars. Honeywell International and a team from NASA Johnson Space Center (JSC) are developing a wastewater processing subsystem that is based on centrifugal vacuum distillation. The wastewater processor, referred to as the Cascade Distillation Subsystem (CDS), utilizes an innovative and efficient multistage thermodynamic process to produce purified water. The rotary centrifugal design of the system also provides gas/liquid phase separation and liquid transport under microgravity conditions. A five-stage subsystem unit has been designed, built, delivered and integrated into the NASA JSC Advanced Water Recovery Systems Development Facility for performance testing. A major test objective of the project is to demonstrate the advancement of the CDS technology from the breadboard level to a subsystem level unit. An initial round of CDS performance testing was completed in fiscal year (FY) 2008. Based on FY08 testing, the system is now in development to support an Exploration Life Support (ELS) Project distillation comparison test expected to begin in early 2009. As part of the project objectives planned for FY09, the system will be reconfigured to support the ELS comparison test. The CDS will then be challenged with a series of human-gene-rated waste streams representative of those anticipated for a lunar outpost. This paper provides a description of the CDS technology, a status of the current project activities, and data on the system s performance to date.

  14. 27 CFR 1.90 - Distilled spirits in bulk.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., NONINDUSTRIAL USE OF DISTILLED SPIRITS AND WINE, BULK SALES AND BOTTLING OF DISTILLED SPIRITS Bulk Sales and Bottling of Distilled Spirits Warehouse Receipts § 1.90 Distilled spirits in bulk. By the terms of the...

  15. 27 CFR 1.91 - Bottled distilled spirits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., NONINDUSTRIAL USE OF DISTILLED SPIRITS AND WINE, BULK SALES AND BOTTLING OF DISTILLED SPIRITS Bulk Sales and Bottling of Distilled Spirits Warehouse Receipts § 1.91 Bottled distilled spirits. The provisions of...

  16. Fate of pesticides in a distilled spirit of barley shochu during the distillation process.

    PubMed

    Inoue, Tomonori; Nagatomi, Yasushi; Kinami, Tomohisa; Uyama, Atsuo; Mochizuki, Naoki

    2010-01-01

    Moromi (the fermented mash) of "mugi shochu" that had been artificially contaminated with pesticides was distilled to elucidate the fate of pesticides in the distillation process. The pesticides residing in the distillate were quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Of the analyzed pesticides (249 compounds), 89% were not detected in the distillate, showing that the distillation process minimized the risk of pesticide contamination. PMID:21150108

  17. Assisted Distillation of Quantum Coherence

    NASA Astrophysics Data System (ADS)

    Chitambar, E.; Streltsov, A.; Rana, S.; Bera, M. N.; Adesso, G.; Lewenstein, M.

    2016-02-01

    We introduce and study the task of assisted coherence distillation. This task arises naturally in bipartite systems where both parties work together to generate the maximal possible coherence on one of the subsystems. Only incoherent operations are allowed on the target system, while general local quantum operations are permitted on the other; this is an operational paradigm that we call local quantum-incoherent operations and classical communication. We show that the asymptotic rate of assisted coherence distillation for pure states is equal to the coherence of assistance, an analog of the entanglement of assistance, whose properties we characterize. Our findings imply a novel interpretation of the von Neumann entropy: it quantifies the maximum amount of extra quantum coherence a system can gain when receiving assistance from a collaborative party. Our results are generalized to coherence localization in a multipartite setting and possible applications are discussed.

  18. Assisted Distillation of Quantum Coherence.

    PubMed

    Chitambar, E; Streltsov, A; Rana, S; Bera, M N; Adesso, G; Lewenstein, M

    2016-02-19

    We introduce and study the task of assisted coherence distillation. This task arises naturally in bipartite systems where both parties work together to generate the maximal possible coherence on one of the subsystems. Only incoherent operations are allowed on the target system, while general local quantum operations are permitted on the other; this is an operational paradigm that we call local quantum-incoherent operations and classical communication. We show that the asymptotic rate of assisted coherence distillation for pure states is equal to the coherence of assistance, an analog of the entanglement of assistance, whose properties we characterize. Our findings imply a novel interpretation of the von Neumann entropy: it quantifies the maximum amount of extra quantum coherence a system can gain when receiving assistance from a collaborative party. Our results are generalized to coherence localization in a multipartite setting and possible applications are discussed. PMID:26943512

  19. High-temperature separation with polymer-coated fiber in packed capillary gas chromatography.

    PubMed

    Saito, Yoshihiro; Ogawa, Mitsuhiro; Imaizumi, Motohiro; Ban, Kazuhiro; Abe, Akira; Takeichi, Tsutomu; Wada, Hiroo; Jinno, Kiyokatsu

    2005-06-01

    High-temperature gas chromatographic separation of several synthetic polymer mixtures with Dexsil-coated fiber-packed columns was studied. A bundle of heat-resistant filaments, Zylon, was longitudinally packed into a short metal capillary, followed by the conventional coating process with Dexsil 300 material. Prior to the packing process the metal capillary was deactivated by the formation of a silica layer. The typical size of the resulting column was 0.3-mm i.d., 0.5-mm o.d., 1-m length, and packed with about 170 filaments of the Dexsil-coated Zylon. The column temperature could be elevated up to 450 degrees C owing to the good thermal stability of the fiber, Dexsil coating, and metal capillary; furthermore, this allowed the separation of low-volatile compounds to be studied. PMID:15933854

  20. Mini-columns for Conducting Breakthrough Experiments. Design and Construction

    SciTech Connect

    Dittrich, Timothy M.; Reimus, Paul William; Ware, Stuart Douglas

    2015-06-11

    Experiments with moderately and strongly sorbing radionuclides (i.e., U, Cs, Am) have shown that sorption between experimental solutions and traditional column materials must be accounted for to accurately determine stationary phase or porous media sorption properties (i.e., sorption site density, sorption site reaction rate coefficients, and partition coefficients or Kd values). This report details the materials and construction of mini-columns for use in breakthrough columns to allow for accurate measurement and modeling of sorption parameters. Material selection, construction techniques, wet packing of columns, tubing connections, and lessons learned are addressed.

  1. Simulation of benzene removal from salt solutions in stripping columns

    SciTech Connect

    Georgeton, G.K.; Wood, J.P.; Wilson, B.M.

    1990-01-01

    A mathematical model was used to simulate the operation of stripping columns to be used in radioactive waste processing at the Savannah River Site. The packed columns will remove trace quantities of benzene from salt solutions by contact with nitrogen. Experimental data from a pilot scale test were evaluated using the model, and the problem of stream channeling was verified with the column simulation. The benzene removal efficiency of the actual columns as a function of varying operating conditions was also simulated. 2 refs., 6 figs., 1 tab.

  2. Quantum Nonlocal Boxes Exhibit Stronger Distillability

    NASA Astrophysics Data System (ADS)

    Rashid, Jibran; Hoyer, Peter

    2012-02-01

    Given the apparent limited distillability of nonlocal boxes (NLBs), we initiate a study of the distillation of correlations for NLBs that output quantum states rather than classical bits. We propose a new non-adaptive protocol for nonlocality distillation which asymptotically distills correlated quantum nonlocal boxes to the value 3.098, whereas in contrast, the optimal non-adaptive parity protocol for classical NLBs asymptotically distills to the value 3.0. The protocol is also proven to be an optimal non-adaptive protocol for 1, 2 and 3 copies by formulating nonlocality distillation as a semi-definite programming optimization problem. Even if we restrict out attention to non-adaptive protocols, qNLBs offer improved distillation over NLBs. A generalization of our SDP approach that allows for adaptive protocols may reveal a similar improvement in general. This may imply distillability for nonlocal correlations that are currently not known to be distillable. As a consequence of the work on nonlocality distillation we provide numerical evidence that correlations with non-trivial marginals which are not known to satisfy the macroscopic locality principle may be distillable even when corresponding correlations with trivial marginals are not.

  3. Enabling Microliquid Chromatography by Microbead Packing of Microchannels

    NASA Technical Reports Server (NTRS)

    Balvin, Manuel; Zheng, Yun

    2014-01-01

    The microbead packing is the critical element required in the success of on-chip microfabrication of critical microfluidic components for in-situ analysis and detection of chiral amino acids. In order for microliquid chromatography to occur, there must be a stationary phase medium within the microchannel that interacts with the analytes present within flowing fluid. The stationary phase media are the microbeads packed by the process discussed in this work. The purpose of the microliquid chromatography is to provide a lightweight, low-volume, and low-power element to separate amino acids and their chiral partners efficiently to understand better the origin of life. In order to densely pack microbeads into the microchannels, a liquid slurry of microbeads was created. Microbeads were extracted from a commercially available high-performance liquid chromatography column. The silica beads extracted were 5 microns in diameter, and had surface coating of phenyl-hexyl. These microbeads were mixed with a 200- proof ethanol solution to create a microbead slurry with the right viscosity for packing. A microfilter is placed at the outlet via of the microchannel and the slurry is injected, then withdrawn across a filter using modified syringes. After each injection, the channel is flushed with ethanol to enhance packing. This cycle is repeated numerous times to allow for a tightly packed channel of microbeads. Typical microbead packing occurs in the macroscale into tubes or channels by using highly pressurized systems. Moreover, these channels are typically long and straight without any turns or curves. On the other hand, this method of microbead packing is completed within a microchannel 75 micrometers in diameter. Moreover, the microbead packing is completed into a serpentine type microchannel, such that it maximizes microchannel length within a microchip. Doing so enhances the interactions of the analytes with the microbeads to separate efficiently amino acids and amino acid enantiomers.

  4. Enabling Microliquid Chromatography by Microbead Packing of Microchannels

    NASA Technical Reports Server (NTRS)

    Balvin, Manuel; Zheng, Yun

    2013-01-01

    The microbead packing is the critical element required in the success of on-chip microfabrication of critical microfluidic components for in-situ analysis and detection of chiral amino acids. In order for microliquid chromatography to occur, there must be a stationary phase medium within the microchannel that interacts with the analytes present within flowing fluid. The stationary phase media are the microbeads packed by the process discussed in this work. The purpose of the microliquid chromatography is to provide a lightweight, low-volume, and low-power element to separate amino acids and their chiral partners efficiently to understand better the origin of life. In order to densely pack microbeads into the microchannels, a liquid slurry of microbeads was created. Microbeads were extracted from a commercially available high-performance liquid chromatography column. The silica beads extracted were 5 microns in diameter, and had surface coating of phenyl-hexyl. These microbeads were mixed with a 200- proof ethanol solution to create a microbead slurry with the right viscosity for packing. A microfilter is placed at the outlet via of the microchannel and the slurry is injected, then withdrawn across a filter using modified syringes. After each injection, the channel is flushed with ethanol to enhance packing. This cycle is repeated numerous times to allow for a tightly packed channel of microbeads. Typical microbead packing occurs in the macroscale into tubes or channels by using highly pressurized systems. Moreover, these channels are typically long and straight without any turns or curves. On the other hand, this method of microbead packing is completed within a microchannel 75 micrometers in diameter. Moreover, the microbead packing is completed into a serpentine type microchannel, such that it maximizes microchannel length within a microchip. Doing so enhances the interactions of the analytes with the microbeads to separate efficiently amino acids and amino acid enantiomers.

  5. Consolidatable gravel pack method

    SciTech Connect

    Friedman, R.H.; Surles, B.W.

    1989-01-31

    A method is described for forming a consolidated gravel pack in a washed-out cavity adjacent to a producing well penetrating a subterranean oil formation comprising the steps of: (a) forming a quantity of resin coated gravel comprising granular mineral particles including gravel, the gravel particles being coated with a resin fluid containing a polymerizable oligomer of furfuryl alcohol resin, a catalyst comprising an oil soluble, very slightly water soluble organic acid and an ester of a weak organic acid to consume water produced by the polymerization of resin, the polymer coated gravel comprising a sticky solid material; (b) preparing an aqueous saline carrier fluid comprising water which is from 70 to 100% saturated with sodium chloride; (c) suspending the resin-coated gravel in the carrier fluid, forming a fluid mixture of resin-coated gravel and carrier fluid; (d) introducing the fluid mixture comprising the resin coated gravel particles suspended in the aqueous saline carrier fluid into the washed-out cavity of the formation adjacent to the producing well and shutting in the well for sufficient period of time to allow polymerization of the resin, forming the permeable gravel pack in the washed-out cavity of the formation.

  6. Regime diagram for the stripping section of a column for purification of the major components from volatile impurities

    SciTech Connect

    Shepelev, E.T.; Kochergin, N.A.; Agafonova, Z.D.

    1987-09-20

    The authors construct liquid-vapor phase equilibrium diagrams depicting the devolatilization of methanol and ethanol from volatile impurities--isopropanol, isobutanol, decane, undecane, dodecane, and tridecane--under distillation conditions in a distillation column. Temperature and pressure as well as concentration dependencies are analyzed as are dilution requirements for the various impurities.

  7. Searching for the perfect packing

    NASA Astrophysics Data System (ADS)

    Herrmann, H. J.; Mahmoodi Baram, R.; Wackenhut, M.

    2003-12-01

    Extremely dense granular packings are needed for high resistance concrete or hard ceramics. They can only be realised when the size distribution of grains is strongly polydisperse. Typically power law distributions give the best results. We present a simple packing model for polydisperse distributions, namely a generalized reversible parking lot model. We also discuss the perfect limit of Apollonian packings in three dimensions and show in particular the existence of space filling bearings rotating without slip and without torsion.

  8. Method for dense packing discovery

    NASA Astrophysics Data System (ADS)

    Kallus, Yoav; Elser, Veit; Gravel, Simon

    2010-11-01

    The problem of packing a system of particles as densely as possible is foundational in the field of discrete geometry and is a powerful model in the material and biological sciences. As packing problems retreat from the reach of solution by analytic constructions, the importance of an efficient numerical method for conducting de novo (from-scratch) searches for dense packings becomes crucial. In this paper, we use the divide and concur framework to develop a general search method for the solution of periodic constraint problems, and we apply it to the discovery of dense periodic packings. An important feature of the method is the integration of the unit-cell parameters with the other packing variables in the definition of the configuration space. The method we present led to previously reported improvements in the densest-known tetrahedron packing. Here, we use the method to reproduce the densest-known lattice sphere packings and the best-known lattice kissing arrangements in up to 14 and 11 dimensions, respectively, providing numerical evidence for their optimality. For nonspherical particles, we report a dense packing of regular four-dimensional simplices with density ϕ=128/219≈0.5845 and with a similar structure to the densest-known tetrahedron packing.

  9. Method for dense packing discovery.

    PubMed

    Kallus, Yoav; Elser, Veit; Gravel, Simon

    2010-11-01

    The problem of packing a system of particles as densely as possible is foundational in the field of discrete geometry and is a powerful model in the material and biological sciences. As packing problems retreat from the reach of solution by analytic constructions, the importance of an efficient numerical method for conducting de novo (from-scratch) searches for dense packings becomes crucial. In this paper, we use the divide and concur framework to develop a general search method for the solution of periodic constraint problems, and we apply it to the discovery of dense periodic packings. An important feature of the method is the integration of the unit-cell parameters with the other packing variables in the definition of the configuration space. The method we present led to previously reported improvements in the densest-known tetrahedron packing. Here, we use the method to reproduce the densest-known lattice sphere packings and the best-known lattice kissing arrangements in up to 14 and 11 dimensions, respectively, providing numerical evidence for their optimality. For nonspherical particles, we report a dense packing of regular four-dimensional simplices with density ϕ=128/219≈0.5845 and with a similar structure to the densest-known tetrahedron packing. PMID:21230619

  10. Polarizable protein packing.

    PubMed

    Ng, Albert H; Snow, Christopher D

    2011-05-01

    To incorporate protein polarization effects within a protein combinatorial optimization framework, we decompose the polarizable force field AMOEBA into low order terms. Including terms up to the third-order provides a fair approximation to the full energy while maintaining tractability. We represent the polarizable packing problem for protein G as a hypergraph and solve for optimal rotamers with the FASTER combinatorial optimization algorithm. These approximate energy models can be improved to high accuracy [root mean square deviation (rmsd) < 1 kJ mol(-1)] via ridge regression. The resulting trained approximations are used to efficiently identify new, low-energy solutions. The approach is general and should allow combinatorial optimization of other many-body problems. PMID:21264879

  11. Packings of soft disks

    NASA Astrophysics Data System (ADS)

    Ziherl, Primoz; Vidmar, Marija

    2011-03-01

    We explore the stability of 2D ordered structures formed by soft disks treated as isotropic solid bodies. Using a variational model, we compute the equilibrium shapes and the elastic energy of disks in regular columnar, honeycomb, square, and hexagonal lattice. The results reproduce the Hertzian interaction in the regime of small deformations. The phase diagram of elastic disks is characterized by broad regions of phase coexistence; its main feature is that the coordination number of the stable phases decreases with density. These results may provide an insight into structure of the non-close-packed lattices observed in certain nanocolloidal systems. This work was supported by Slovenian Research Agency (grant No. P1-0055) and by EU through ITN COMPLOIDS (grant FP7-People-ITN-2008 No. 234810).

  12. Vapor Compression Distillation Flight Experiment

    NASA Technical Reports Server (NTRS)

    Hutchens, Cindy F.

    2002-01-01

    One of the major requirements associated with operating the International Space Station is the transportation -- space shuttle and Russian Progress spacecraft launches - necessary to re-supply station crews with food and water. The Vapor Compression Distillation (VCD) Flight Experiment, managed by NASA's Marshall Space Flight Center in Huntsville, Ala., is a full-scale demonstration of technology being developed to recycle crewmember urine and wastewater aboard the International Space Station and thereby reduce the amount of water that must be re-supplied. Based on results of the VCD Flight Experiment, an operational urine processor will be installed in Node 3 of the space station in 2005.

  13. Distillation apparatus with solar tracker

    SciTech Connect

    Snyder, W.L.

    1982-04-20

    A solar distillation unit is disclosed capable of operating entirely off solar radiation and intended for large scale industrial use offshore. A lens focusing system housed within an enclosed shell focuses the incident radiation from the sun on a heating element. Saltwater or contaminated fresh water is ejected toward the heating element at a predetermined rate resulting in the immediate evaporation of the water. The water vapor migrates and condenses on the cooler inner surface of the shell running to the bottom where it is collected and removed as fresh water.

  14. Small codes for magic state distillation

    NASA Astrophysics Data System (ADS)

    Howard, Mark; Dawkins, Hillary

    2016-03-01

    Magic state distillation is a critical component in leading proposals for fault-tolerant quantum computation. Relatively little is known, however, about how to construct a magic state distillation routine or, more specifically, which stabilizer codes are suitable for the task. While transversality of a non-Clifford gate within a code often leads to efficient distillation routines, it appears to not be a necessary condition. Here we have examined a number of small stabilizer codes and highlight a handful of which displaying interesting, albeit inefficient, distillation behaviour. Many of these distill noisy states right up to the boundary of the known undististillable region, while some distill toward non-stabilizer states that have not previously been considered.

  15. 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.

  16. A new procedure for the determination of distillation temperature distribution of high-boiling petroleum products and fractions.

    PubMed

    Boczkaj, Grzegorz; Przyjazny, Andrzej; Kamiński, Marian

    2011-03-01

    The distribution of distillation temperatures of liquid and semi-fluid products, including petroleum fractions and products, is an important process and practical parameter. It provides information on properties of crude oil and content of particular fractions, classified on the basis of their boiling points, as well as the optimum conditions of atmospheric or vacuum distillation. At present, the distribution of distillation temperatures is often investigated by simulated distillation (SIMDIS) using capillary gas chromatography (CGC) with a short capillary column with polydimethylsiloxane as the stationary phase. This paper presents the results of investigations on the possibility of replacing currently used CGC columns for SIMDIS with a deactivated fused silica capillary tube without any stationary phase. The SIMDIS technique making use of such an empty fused silica column allows a considerable lowering of elution temperature of the analytes, which results in a decrease of the final oven temperature while ensuring a complete separation of the mixture. This eliminates the possibility of decomposition of less thermally stable mixture components and bleeding of the stationary phase which would result in an increase of the detector signal. It also improves the stability of the baseline, which is especially important in the determination of the end point of elution, which is the basis for finding the final temperature of distillation. This is the key parameter for the safety process of hydrocracking, where an excessively high final temperature of distillation of a batch can result in serious damage to an expensive catalyst bed. This paper compares the distribution of distillation temperatures of the fraction from vacuum distillation of petroleum obtained using SIMDIS with that obtained by the proposed procedure. A good agreement between the two procedures was observed. In addition, typical values of elution temperatures of n-paraffin standards obtained by the two procedures were compared. Finally, the agreement between boiling points of polar compounds determined from their retention times and actual boiling points was investigated. PMID:21153592

  17. Distillation of liquid fuels by thermogravimetry

    SciTech Connect

    Huang, He; Wang, Keyu; Wang, Shaojie; Klein, M.T.; Calkins, W.H.

    1996-12-31

    In this paper, design and operation of a custom-built thermogravimetric apparatus for the distillation of liquid fuels are reported. Using a sensitive balance with scale of 0.001 g and ASTM distillation glassware, several petroleum and petroleum-derived samples have been analyzed by the thermogravimetric distillation method. When the ASTM distillation glassware is replaced by a micro-scale unit, sample size could be reduced from 100 g to 5-10 g. A computer program has been developed to transfer the data into a distillation plot, e.g. Weight Percent Distilled vs. Boiling Point. It also generates a report on the characteristic distillation parameters, such as, IBP (Initial Boiling Point), FBP (Final Boiling Point), and boiling point at 50 wt% distilled. Comparison of the boiling point distributions determined by TG (thermogravimetry) with those by SimDis GC (Simulated-Distillation Gas Chromatography) on two liquid fuel samples (i.e. a decanted oil and a filtered crude oil) are also discussed in this paper.

  18. Packing Products: Polystyrene vs. Cornstarch

    ERIC Educational Resources Information Center

    Starr, Suzanne

    2009-01-01

    Packing materials such as polystyrene take thousands of years to decompose, whereas packing peanuts made from cornstarch, which some companies are now using, can serve the same purpose, but dissolve in water. The author illustrates this point to her class one rainy day using the sculptures students made from polystyrene and with the cornstarch…

  19. Column Liquid Chromatography.

    ERIC Educational Resources Information Center

    Majors, Ronald E.; And Others

    1984-01-01

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

  20. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721.4500 Protection of Environment... residues and ethylamine distillation residues. (a) Chemical substances and significant new use subject...

  1. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721.4500 Protection of Environment... residues and ethylamine distillation residues. (a) Chemical substances and significant new use subject...

  2. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721.4500 Protection of Environment... residues and ethylamine distillation residues. (a) Chemical substances and significant new use subject...

  3. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721.4500 Protection of Environment... residues and ethylamine distillation residues. (a) Chemical substances and significant new use subject...

  4. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  5. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  6. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  7. Recycling of acetone by distillation

    SciTech Connect

    Brennan, D.L.; Campbell, B.A.; Phelan, J.E.; Harper, M.

    1992-09-01

    The Resource Conservation Recovery Act (RCRA) identifies spent acetone solvent as a listed hazardous waste. At Fernald, acetone has been spent that has been contaminated with radionuclides and therefore is identified as a mixed hazardous waste. At the time of this publication there is no available approved method of recycling or disposal of radioactively contaminated spent acetone solvent. The Consent Decree with the Ohio EPA and the Consent Agreement with the United States EPA was agreed upon for the long-term compliant storage of hazardous waste materials. The purpose of this project was to demonstrate the feasibility for safely decontaminating spent acetone to background levels of radioactivity for reuse. It was postulated that through heat distillation, radionuclides could be isolated from the spent acetone.

  8. Recycling of Waste Acetone by Fractional Distillation

    ERIC Educational Resources Information Center

    Weires, Nicholas A.; Johnston, Aubrey; Warner, Don L.; McCormick, Michael M.; Hammond, Karen; McDougal, Owen M.

    2011-01-01

    Distillation is a ubiquitous technique in the undergraduate organic chemistry curriculum; the technique dates back to ca. 3500 B.C.E. With the emergence of green chemistry in the 1990s, the importance of emphasizing responsible waste management practices for future scientists is paramount. Combining the practice of distillation with the message

  9. 27 CFR 24.216 - Distilling material.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Distilling material. 24.216 Section 24.216 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL WINE Production of Other Than Standard Wine § 24.216 Distilling...

  10. 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...

  11. Distillation of Bell states in open systems

    SciTech Connect

    Isasi, E.; Mundarain, D.

    2010-04-15

    In this work we show that the distillation protocol proposed by P. Chen et al. [Phys. Rev. A 54, 3824 (1996)] allows one to distill Bell states at any time for a system evolving in vacuum and prepared in an initial singlet. It is also shown that the same protocol, applied in nonzero temperature thermal baths, yields a considerable recovering of entanglement.

  12. 27 CFR 19.316 - Distillation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Distillation. 19.316 Section 19.316 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... purpose of redistillation is not deemed to be a break in the continuity of the distilling...

  13. Recycling of Waste Acetone by Fractional Distillation

    ERIC Educational Resources Information Center

    Weires, Nicholas A.; Johnston, Aubrey; Warner, Don L.; McCormick, Michael M.; Hammond, Karen; McDougal, Owen M.

    2011-01-01

    Distillation is a ubiquitous technique in the undergraduate organic chemistry curriculum; the technique dates back to ca. 3500 B.C.E. With the emergence of green chemistry in the 1990s, the importance of emphasizing responsible waste management practices for future scientists is paramount. Combining the practice of distillation with the message…

  14. Valve stem and packing assembly

    DOEpatents

    Wordin, John J.

    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.

  15. 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.

  16. 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., π /√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.

  17. Quality evaluation of agricultural distillates using different types of electronic noses

    NASA Astrophysics Data System (ADS)

    Dymerski, Tomasz; Gebicki, Jacek; Namieśnik, Jacek

    2014-08-01

    The paper presents the results of investigation on quality evaluation of agricultural distillates using a prototype of electronic nose instrument and a commercial electronic nose of Fast/Flash GC type- HERACLES II. The prototype was equipped with TGS type semiconductor sensors. HERACLES II included two chromatographic columns with different polarity of stationary phase and two FID detectors. In case of the prototype volatile fraction of the agricultural distillate was prepared via barbotage process, whereas HERACLES II analysed the headspace fraction. Classification of the samples into three quality classes was performed using: quadratic discriminant function (QDA), supported with cross-validation method. Over 95% correct classification of the agricultural distillates into particular quality classes was observed for the analyses with HERACLES II. The prototype of electronic nose provided correct classification at the level of 70%.

  18. 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

  19. 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

  20. Packed Bed Reactor Experiment - Duration: 17 seconds.

    NASA Video Gallery

    The purpose of the Packed Bed Reactor Experiment in low gravity is to determine how a mixture of gas and liquid flows through a packed bed in reduced gravity. A packed bed consists of a metal pipe ...

  1. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

  2. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

  3. Comparison of advanced distillation control methods. Second annual report

    SciTech Connect

    Riggs, J.B.

    1996-11-01

    Detailed dynamic simulations of two industrial distillation columns (a propylene/propane splitter and a xylene/toluene column) have been used to study the issue of configuration selection for diagonal PI dual composition controls. Auto Tune Variation (ATV) identification with on-line detuning was used for tuning the diagonal proportional integral (PI) composition controls. Each configuration was evaluated with respect to steady-state relative gain array (RGA) values, sensitivity to feed composition changes, and open loop dynamic performance. Each configuration was tuned using setpoint changes over a wider range of operation for robustness and tested for feed composition upsets. Overall, configuration selection was shown to have a dominant effect upon control performance. Configuration analysis tools (e.g., RGA, condition number, disturbance sensitivity) were found to reject configuration choices that are obviously poor choices, but were unable to critically differentiate between the remaining viable choices. Configuration selection guidelines are given although it is demonstrated that the most reliable configuration selection approach is based upon testing the viable configurations using dynamic column simulators.

  4. Comparison of advanced distillation control methods. Second annual report

    SciTech Connect

    1996-11-01

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to study the issue of configuration selection for diagonal PI dual composition controls. ATV identification with on-line detuning was used for tuning the diagonal PI composition controllers. Each configuration was evaluated with respect to steady-state RGA values, sensitivity to feed composition changes, and open loop dynamic performance. Each configuration was tuned using setpoint changes over a wider range of operation for robustness and tested for feed composition upsets. Overall, configuration selection was shown to have a dominant effect upon control performance. Configuration analysis tools (e.g., RGA, condition number, disturbance sensitivity), were found to reject configuration choices that are obviously poor choices, but were unable to critically differentiate between the remaining viable choices. Configuration selection guidelines are given although it is demonstrated that the most reliable configuration selection approach is based upon testing the viable configurations using dynamic column simulators.

  5. Measurement of the axial and radial temperature profiles of a chromatographic column. Influence of thermal insulation on column efficiency.

    PubMed

    Gritti, Fabrice; Guiochon, Georges

    2007-01-01

    The temperatures of the metal wall along a chromatographic column (longitudinal temperature gradients) and of the liquid phase across the outlet section of the column (radial temperature gradients) were measured at different flow rates with the same chromatographic column (250 mm x 4.6 mm). The column was packed with 5 microm C18-bonded silica particles. The measurements were carried out with surface and immersion thermocouples (all junction Type T, +/-0.1 K) that measure the local temperature. The column was either left in a still-air bath (ambient temperature, T(ext) = 295-296 K) or insulated in a packing foam to avoid air convection around its surface. The temperature profiles were measured at several values of the inlet pressure (approximately = 100, 200, 300 and 350 bar) and with two mobile phases, pure methanol and a 2.5:97.5 (v/v, %) methanol:water solution. The experimental results show that the longitudinal temperature gradients never exceeded 8 K for a pressure drop of 350 bars. In the presence of the insulating foam, the longitudinal temperature gradients become quasi-linear and the column temperature increases by +1 and +3 K with a water-rich (heat conductivity approximately = 0.6 W/m/K) and pure methanol (heat conductivity approximately = 0.2 W/m/K), respectively. The radial temperature gradients are maximum with methanol (+1.5 K at 290 bar inlet pressure) and minimum with water (+0.8 K at 290 bar), as predicted by the solution of the heat transfer balance in a chromatographic column. The profile remains parabolic all along the column. Combining the results of these measurements (determination of the boundary conditions on the wall, at column inlet and at column outlet) with calculations using a realistic model of heat dispersion in a porous medium, the temperature inside the column could be assessed for any radial and axial position. PMID:17141792

  6. EFFECT OF NITRATE-BASED BIOREMEDIATION ON CONTAMINANT DISTRIBUTION AND SEDIMENT TOXICITY-COLUMN STUDY

    EPA Science Inventory

    A laboratory column study was set up to evaluate changes in contaminant distribution and sediment toxicity following nitrate-based bioremediation and to correlate toxicity reduction with loss of fuel components. Glass columns were packed with sediment from an aquifer that had be...

  7. 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...

  8. 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...

  9. Pattern formations and optimal packing.

    PubMed

    Mityushev, Vladimir

    2016-04-01

    Patterns of different symmetries may arise after solution to reaction-diffusion equations. Hexagonal arrays, layers and their perturbations are observed in different models after numerical solution to the corresponding initial-boundary value problems. We demonstrate an intimate connection between pattern formations and optimal random packing on the plane. The main study is based on the following two points. First, the diffusive flux in reaction-diffusion systems is approximated by piecewise linear functions in the framework of structural approximations. This leads to a discrete network approximation of the considered continuous problem. Second, the discrete energy minimization yields optimal random packing of the domains (disks) in the representative cell. Therefore, the general problem of pattern formations based on the reaction-diffusion equations is reduced to the geometric problem of random packing. It is demonstrated that all random packings can be divided onto classes associated with classes of isomorphic graphs obtained from the Delaunay triangulation. The unique optimal solution is constructed in each class of the random packings. If the number of disks per representative cell is finite, the number of classes of isomorphic graphs, hence, the number of optimal packings is also finite. PMID:26852668

  10. Inelastic column behavior

    NASA Technical Reports Server (NTRS)

    Duberg, John E; Wilder, Thomas W , III

    1952-01-01

    The significant findings of a theoretical study of column behavior in the plastic stress range are presented. When the behavior of a straight column is regarded as the limiting behavior of an imperfect column as the initial imperfection (lack of straightness) approaches zero, the departure from the straight configuration occurs at the tangent-modulus load. Without such a concept of the behavior of a straight column, one is led to the unrealistic conclusion that lateral deflection of the column can begin at any load between the tangent-modulus value and the Euler load, based on the original elastic modulus. A family of curves showing load against lateral deflection is presented for idealized h-section columns of various lengths and of various materials that have a systematic variation of their stress-strain curves.

  11. Gearing of molecular swirls: columnar packing of nematogenic hexakis(4-alkoxyphenylethynyl)benzene derivatives.

    PubMed

    Lee, Shern-Long; Lin, Hsing-An; Lin, Yi-Hui; Chen, Hsiu-Hui; Liao, Ching-Ting; Lin, Tzu-Ling; Chu, Yi-Chen; Hsu, Hsiu-Fu; Chen, Chun-hsien; Lee, Jey-Jau; Hung, Wen-Yi; Liu, Qu-Yuan; Wu, Chunhung

    2011-01-17

    Through molecular design and straightforward synthesis, incorporating an additional alkoxy chain onto various numbers of peripheral phenyls in nematogenic hexakis(4-alkoxyphenylethynyl)benzene was achieved to generate columnar phases with significantly expanded temperature ranges. For the compound with two decyloxy chains on every peripheral phenyl, scanning tunnelling microscopic studies indicate the molecule adopts a preferred molecular-swirl geometry by restricting the conformational arrangement of the alkoxy side chains. Cooperative packing of the molecular swirls by a lock-in mechanism among columns results in a stable helical column packing evidenced by powder X-ray diffraction. PMID:21226093

  12. 27 CFR 27.31 - Warehouse receipts covering distilled spirits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... BEER Dealer Registration and Recordkeeping § 27.31 Warehouse receipts covering distilled spirits. The... sale, warehouse receipts for distilled spirits stored in customs bonded warehouses, or elsewhere,...

  13. 27 CFR 27.31 - Warehouse receipts covering distilled spirits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... BEER Dealer Registration and Recordkeeping § 27.31 Warehouse receipts covering distilled spirits. The... sale, warehouse receipts for distilled spirits stored in customs bonded warehouses, or elsewhere,...

  14. Cascade Distiller System Performance Testing Interim Results

    NASA Technical Reports Server (NTRS)

    Callahan, Michael R.; Pensinger, Stuart; Sargusingh, Miriam J.

    2014-01-01

    The Cascade Distillation System (CDS) is a rotary distillation system with potential for greater reliability and lower energy costs than existing distillation systems. Based upon the results of the 2009 distillation comparison test (DCT) and recommendations of the expert panel, the Advanced Exploration Systems (AES) Water Recovery Project (WRP) project advanced the technology by increasing reliability of the system through redesign of bearing assemblies and improved rotor dynamics. In addition, the project improved the CDS power efficiency by optimizing the thermoelectric heat pump (TeHP) and heat exchanger design. Testing at the NASA-JSC Advanced Exploration System Water Laboratory (AES Water Lab) using a prototype Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell d International, Torrance, Calif.) with test support equipment and control system developed by Johnson Space Center was performed to evaluate performance of the system with the upgrades as compared to previous system performance. The system was challenged with Solution 1 from the NASA Exploration Life Support (ELS) distillation comparison testing performed in 2009. Solution 1 consisted of a mixed stream containing human-generated urine and humidity condensate. A secondary objective of this testing is to evaluate the performance of the CDS as compared to the state of the art Distillation Assembly (DA) used in the ISS Urine Processor Assembly (UPA). This was done by challenging the system with ISS analog waste streams. This paper details the results of the AES WRP CDS performance testing.

  15. Biodiesel production from integration between reaction and separation system: reactive distillation process.

    PubMed

    da Silva, Nívea de Lima; Santander, Carlos Mario Garcia; Batistella, César Benedito; Filho, Rubens Maciel; Maciel, Maria Regina Wolf

    2010-05-01

    Biodiesel is a clean burning fuel derived from a renewable feedstock such as vegetable oil or animal fat. It is biodegradable, non-inflammable, non-toxic, and produces lesser carbon monoxide, sulfur dioxide, and unburned hydrocarbons than petroleum-based fuel. The purpose of the present work is to present an efficient process using reactive distillation columns applied to biodiesel production. Reactive distillation is the simultaneous implementation of reaction and separation within a single unit of column. Nowadays, it is appropriately called "Intensified Process". This combined operation is especially suited for the chemical reaction limited by equilibrium constraints, since one or more of the products of the reaction are continuously separated from the reactants. This work presents the biodiesel production from soybean oil and bioethanol by reactive distillation. Different variables affect the conventional biodiesel production process such as: catalyst concentration, reaction temperature, level of agitation, ethanol/soybean oil molar ratio, reaction time, and raw material type. In this study, the experimental design was used to optimize the following process variables: the catalyst concentration (from 0.5 wt.% to 1.5 wt.%), the ethanol/soybean oil molar ratio (from 3:1 to 9:1). The reactive column reflux rate was 83 ml/min, and the reaction time was 6 min. PMID:20221864

  16. Entanglement distillation using the exchange interaction

    NASA Astrophysics Data System (ADS)

    Auer, Adrian; Schwonnek, René; Schoder, Christian; Dammeier, Lars; Werner, Reinhard F.; Burkard, Guido

    2016-03-01

    A key ingredient of quantum repeaters is entanglement distillation, i.e., the generation of high-fidelity entangled qubits from a larger set of pairs with lower fidelity. Here, we present entanglement distillation protocols based on qubit couplings that originate from exchange interaction. First, we make use of asymmetric bilateral two-qubit operations generated from anisotropic exchange interaction and show how to distill entanglement using two input pairs. We furthermore consider the case of three input pairs coupled through isotropic exchange. Here, we characterize a set of protocols which are optimizing the trade-off between the fidelity increase and the probability of a successful run.

  17. Design and operating targets for nonideal multicomponent batch distillation

    SciTech Connect

    Bernot, C.; Doherty, M.F.; Malone, M.F. )

    1993-02-01

    A method is reported to estimate the batch sizes, operating times, equipment sizes, utility loads, and costs for the batch distillation of nonideal multicomponent mixtures. The method provides an estimate for both the design and the operating policy for the reflux or reboil ratio without the need to integrate the full column model numerically. This operating policy approximates the constant product composition policy for high purities and high fractional recoveries and shows a substantial cost savings over the constant reflux or reboil policies, primarily on account of a substantial reduction in the vapor rate. The approach provides a good approximation to the results of a detailed optimization in an example for a binary mixture. A more interesting application is illustrated for the separation of a quaternary azeotropic mixture arising from the transesterification of ethyl acetate with methanol to produce ethanol and methyl acetate.

  18. Low capital implementation of distributed distillation in ethylene recovery

    DOEpatents

    Reyneke, Rian; Foral, Michael J.; Lee, Guang-Chung

    2006-10-31

    An apparatus for recovering ethylene from a hydrocarbon feed stream, where the apparatus is a single distillation column pressure shell encasing an upper region and a lower region. The upper region houses an ethylene distributor rectifying section and the lower region houses a C2 distributor section and an ethylene distributor stripping section. Vapor passes from the lower region into the upper region, and liquid passes from the upper region to the lower region. The process for recovering the ethylene is also disclosed. The hydrocarbon feed stream is introduced into the C2 distributor section, and after a series of stripping and refluxing steps, distinct hydrocarbon products are recovered from the C2 distributor section, the ethylene distributor stripping section, and the ethylene distributor rectifying section, respectively.

  19. Preparation of a super-long two column chromatography system and its application in separating glycosylated puerarin.

    PubMed

    Zhu, Shouchuang; Xu, Haidong; Yu, Cigang; Ding, Juanfang; Chen, Ting; Jiang, Jierong; Dai, Yijun; Liu, Guiyou; Huang, Guodong; Chai, Nan; Jiang, Xuhua; Yuan, Sheng

    2009-12-01

    Separation of Puerarin-7-O-glucoside from its precursor, puerarin, using a common chromatography column packed with AB-8 macroporous resin was unsuccessful. Therefore, in this study a 8 m super-long flexible reinforced PVC column was externally added to the common column in order to improve the chromatography efficiency by increasing the number of theoretical plates. Both the PVC and common columns were separately packed with AB-8 macroporous resin slurry. The packed PVC column was coiled after washing and stored until use. The microbial transformation mixture with puerarin-7-O-glucoside and puerarin (250 mL) was loaded onto the common column, followed by washing with 2000 mL H(2)O. After attaching the coiled external PVC column to the common column, a linear gradient of 10-30% ethanol was applied to elute the target compound. Two peaks appeared: peak I contained puerarin-7-O-glucoside at 97.9% purity and 88.1% recovery rate, and peak II was puerarin at 98.7% purity and 87.0% recovery rate. The use of the coiled external flexible reinforced PVC column avoided spatial restriction for long columns, which made it much more convenient for column packing and chromatography operations. Furthermore, this method eliminated the resin blockage problem caused by stationary water pressure in a rigid vertical long column. Using an external super-long column, the PVC tube was connected with the common column only during elution, which avoided delay in time period during sample loading and column washes associated with the use of long external columns. PMID:19603387

  20. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged.... 3 2 “Fairly tight” means that apples are of the proper size for molds or cell compartments in...

  1. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged.... 3 2 “Fairly tight” means that apples are of the proper size for molds or cell compartments in...

  2. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S. Standard bushel baskets, or half-bushel baskets,...

  3. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S. Standard bushel baskets, or half-bushel baskets,...

  4. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S....

  5. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S. Standard bushel baskets, or half-bushel baskets,...

  6. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S....

  7. 7 CFR 51.1527 - Standard pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Fresh Plums and Prunes Standard Pack § 51.1527 Standard pack. (a) Packing. (1) All... plums or prunes in the top layer of any package shall be reasonably representative in quality and size of those in the remainder of the package. (3) “Well filled” means that the plums or prunes packed...

  8. 7 CFR 51.1527 - Standard pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Fresh Plums and Prunes Standard Pack § 51.1527 Standard pack. (a) Packing. (1) All... plums or prunes in the top layer of any package shall be reasonably representative in quality and size of those in the remainder of the package. (3) “Well filled” means that the plums or prunes packed...

  9. Minimizing corrosion in coal liquid distillation

    DOEpatents

    Baumert, Kenneth L.; Sagues, Alberto A.; Davis, Burtron H.

    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.

  10. Inflatable Column Structure

    NASA Technical Reports Server (NTRS)

    Hedgepeth, J. M.

    1985-01-01

    Lightweight structural member easy to store. Billowing between circumferential loops of fiber inflated column becomes series of cells. Each fiber subjected to same tension along entire length (though tension is different in different fibers). Member is called "isotensoid" column. Serves as jack for automobiles or structures during repairs. Also used as support for temporary bleachers or swimming pools.

  11. Support Column of Bridge

    Support column of bridge across Struve Slough, Highway 1. Enlargement of hole where support enters the ground is an effect of lateral shaking, which caused the concrete to break up where the column joined the bridge and was instrumental in the roadbed collapse....

  12. Hard sphere packings within cylinders.

    PubMed

    Fu, Lin; Steinhardt, William; Zhao, Hao; Socolar, Joshua E S; Charbonneau, Patrick

    2016-02-23

    Arrangements of identical hard spheres confined to a cylinder with hard walls have been used to model experimental systems, such as fullerenes in nanotubes and colloidal wire assembly. Finding the densest configurations, called close packings, of hard spheres of diameter σ in a cylinder of diameter D is a purely geometric problem that grows increasingly complex as D/σ increases, and little is thus known about the regime for D > 2.873σ. In this work, we extend the identification of close packings up to D = 4.00σ by adapting Torquato-Jiao's adaptive-shrinking-cell formulation and sequential-linear-programming (SLP) technique. We identify 17 new structures, almost all of them chiral. Beyond D ≈ 2.85σ, most of the structures consist of an outer shell and an inner core that compete for being close packed. In some cases, the shell adopts its own maximum density configuration, and the stacking of core spheres within it is quasiperiodic. In other cases, an interplay between the two components is observed, which may result in simple periodic structures. In yet other cases, the very distinction between the core and shell vanishes, resulting in more exotic packing geometries, including some that are three-dimensional extensions of structures obtained from packing hard disks in a circle. PMID:26843132

  13. Valve packings conquer fugitive emissions

    SciTech Connect

    1995-11-01

    In the early 1990s, when the US Environmental Protection Agency (EPA; Washington, D.C.) declared its intent to regulate fugitive emissions from valve-stem leakage, much of the chemical process industries (CPI) responded with fear and uncertainty. The biggest fear was that valve packing would not meet the required limits on leak rates and that expensive bellows seals may be required on many applications. The uncertainly was about how much it would cost. Today, for the most part, these concerns have been mitigated. It is estimated that about 80--90% of valves satisfy the emission requirements. The rest need some improvement in their packing systems to meet the regulations. Generally, these valves can be brought within compliance if the packing designers follow a few basic principles: Employ less-pliable outer rings and more-pliable inner rings; and don`t use excessive packing. While interest in valve packing remains high, mechanical seals continue to become more user-friendly. Many of those covered below are designed to run dry, and some can even tolerate high shaft-wobble without damage. Also look for improved flange gaskets and a host of seals to protect bearings. Twenty-one summaries are presented on new products and services.

  14. Glass-silicon column

    DOEpatents

    Yu, Conrad M.

    2003-12-30

    A glass-silicon column that can operate in temperature variations between room temperature and about 450.degree. C. The glass-silicon column includes large area glass, such as a thin Corning 7740 boron-silicate glass bonded to a silicon wafer, with an electrode embedded in or mounted on glass of the column, and with a self alignment silicon post/glass hole structure. The glass/silicon components are bonded, for example be anodic bonding. In one embodiment, the column includes two outer layers of silicon each bonded to an inner layer of glass, with an electrode imbedded between the layers of glass, and with at least one self alignment hole and post arrangement. The electrode functions as a column heater, and one glass/silicon component is provided with a number of flow channels adjacent the bonded surfaces.

  15. 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.

  16. Multipartite secret key distillation and bound entanglement

    SciTech Connect

    Augusiak, Remigiusz; Horodecki, Pawel

    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.

  17. Quantum Nonlocal Boxes Exhibit Stronger Distillability

    NASA Astrophysics Data System (ADS)

    Høyer, Peter; Rashid, Jibran

    2013-06-01

    The hypothetical nonlocal box (NLB) proposed by Popescu and Rohrlich allows two spatially separated parties, Alice and Bob, to exhibit stronger than quantum correlations. If the generated correlations are weak, they can sometimes be distilled into a stronger correlation by repeated applications of the NLB. Motivated by the limited distillability of NLBs, we initiate here a study of the distillation of correlations for nonlocal boxes that output quantum states rather than classical bits (qNLBs). We propose a new protocol for distillation and show that it asymptotically distills a class of correlated quantum nonlocal boxes to the value (1)/(2)(3√ {3}+1) ≈ 3.098076, whereas in contrast, the optimal non-adaptive parity protocol for classical nonlocal boxes asymptotically distills only to the value 3.0. We show that our protocol is an optimal non-adaptive protocol for 1, 2 and 3 qNLB copies by constructing a matching dual solution for the associated primal semidefinite program (SDP). We conclude that qNLBs are 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 are known to limit nonlocal correlations under the framework of qNLBs rather than NLBs.

  18. 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.

  19. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  20. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  1. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  2. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  3. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  4. Cylinder valve packing nut studies

    SciTech Connect

    Blue, S.C.

    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.

  5. Nuclear reactor control column

    DOEpatents

    Bachovchin, Dennis M.

    1982-01-01

    The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest 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.

  6. DE-ENTRAINMENT COLUMN

    DOEpatents

    Mooradian, A.J.

    1958-07-01

    A de-entrainnnent colunnn is described for removing substances from a stream of vapor coming from a distillation apparatus. The device comprises a hollow cylindrical body mounted with its axis vertical on a flange on the upper slde of a vaporizing vessel; two sintered metal circular discs through which all the vapor passes mounted in axially spaced relationship in the cylindrical body; and two semi-circular baffle plates mounted in spaced relationship between the discs.

  7. Model of decision system for 13C Isotope Separation column

    NASA Astrophysics Data System (ADS)

    Boca, M. L.

    2015-11-01

    This paper presents the model of a decisional system for 13C Isotope Separation column, which is used to detect mission critical situation. The start model was a model of one distributed control system of critical situations that may arise in the operation of the distillation column. The research work it is proposed a model of decision system which implement a temperature sensor inside of liquid nitrogen level in the condenser. The condenser is a part of column where take place the cryogenic process using nitrogen liquid. The work temperature is very low about -192oC, and because the temperature can grow or go down more than 2 degrees is a very critical location inside the column. In this way the column has a deeply monitor and supervised and it take a decision in a proper time when the temperature is grow up or getting down and became a critical situation. For monitor and supervised it was used MatLAB SimuLink. The model, the decision system gives a signal to one sensor when something is wrong in the condenser which is the most critical place of the isotopic column. In this way it creates an alarm that something is getting wrong in the isotopic column.

  8. Fixed Packed Bed Reactors in Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Motil, Brian J.; Balakotaiah, Vemuri; Kamotani, Yasuhiro; McCready, Mark J.

    2004-01-01

    We present experimental data on flow pattern transitions, pressure drop and flow characteristics for cocurrent gas-liquid flow through packed columns in microgravity. The flow pattern transition data indicates that the pulse flow regime exists over a wider range of gas and liquid flow rates under microgravity conditions compared to 1-g and the widely used Talmor map in 1-g is not applicable for predicting the transition boundaries. A new transition criterion between bubble and pulse flow in microgravity is proposed and tested using the data. Since there is no static head in microgravity, the pressure drop measured is the true frictional pressure drop. The pressure drop data, which has much smaller scatter than most reported 1-g data clearly shows that capillary effects can enhance the pressure drop (especially in the bubble flow regime) as much as 200% compared to that predicted by the single phase Ergun equation. The pressure drop data are correlated in terms of a two-phase friction factor and its dependence on the gas and liquid Reynolds numbers and the Suratman number. The influence of gravity on the pulse amplitude and frequency is also discussed and compared to that under normal gravity conditions. Experimental work is planned to determine the gas-liquid and liquid-solid mass transfer coefficients. Because of enhanced interfacial effects, we expect the gas-liquid transfer coefficients kLa and kGa (where a is the gas-liquid interfacial area) to be higher in microgravity than in normal gravity at the same flow conditions. This will be verified by gas absorption experiments, with and without reaction in the liquid phase, using oxygen, carbon dioxide, water and dilute aqueous amine solutions. The liquid-solid mass transfer coefficient will also be determined in the bubble as well as the pulse flow regimes using solid benzoic acid particles in the packing and measuring their rate of dissolution. The mass transfer coefficients in microgravity will be compared to those in normal gravity cocurrent flow to determine the mass transfer enhancement and propose new mass transfer correlations for two-phase gas-liquid flows through packed beds in microgravity.

  9. Fixed Packed Bed Reactors in Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Motil, Brian J.; Balakotaiah, Vemuri; Kamotani, Yasuhiro; McCready, Mark J.

    2004-01-01

    We present experimental data on flow pattern transitions, pressure drop and flow characteristics for cocurrent gas-liquid flow through packed columns in microgravity. The flow pattern transition data indicates that the pulse flow regime exists over a wider range of gas and liquid flow rates under microgravity conditions compared to 1-g and the widely used Talmor map in 1-g is not applicable for predicting the transition boundaries. A new transition criterion between bubble and pulse flow in microgravity is proposed and tested using the data. Since there is no static head in microgravity, the pressure drop measured is the true frictional pressure drop. The pressure drop data, which has much smaller scatter than most reported 1-g data clearly shows that capillary effects can enhance the pressure drop (especially in the bubble flow regime) as much as 200% compared to that predicted by the single phase Ergun equation. The pressure drop data are correlated in terms of a two-phase friction factor and its dependence on the gas and liquid Reynolds numbers and the Suratman number. The influence of gravity on the pulse amplitude and frequency is also discussed and compared to that under normal gravity conditions. Experimental work is planned to determine the gas-liquid mass transfer coefficients. Because of enhanced interfacial effects, we expect the gas-liquid transfer coefficients k(L)a and k(G)a (where a is the gas-liquid interfacial area) to be higher in microgravity than in normal gravity at the same flow conditions. This will be verified by gas absorption experiments, with and without reaction in the liquid phase, using oxygen, carbon dioxide, water and dilute aqueous amine solutions. The liquid-solid mass transfer coefficient will also be determined in the bubble as well as the pulse flow regimes using solid benzoic acid particles in the packing and measuring their rate of dissolution. The mass transfer coefficients in microgravity will be compared to those in normal gravity cocurrent flow to determine the mass transfer enhancement and propose new mass transfer correlations for two-phase gas-liquid flows through packed beds in microgravity.

  10. Larger voids in mechanically stable, loose packings of 1.3μm frictional, cohesive particles: Their reconstruction, statistical analysis, and impact on separation efficiency.

    PubMed

    Reising, Arved E; Godinho, Justin M; Hormann, Kristof; Jorgenson, James W; Tallarek, Ulrich

    2016-03-01

    Lateral transcolumn heterogeneities and the presence of larger voids in a packing (comparable to the particle size) can limit the preparation of efficient chromatographic columns. Optimizing and understanding the packing process provides keys to better packing structures and column performance. Here, we investigate the slurry-packing process for a set of capillary columns packed with C18-modified, 1.3μm bridged-ethyl hybrid porous silica particles. The slurry concentration used for packing 75μm i.d. fused-silica capillaries was increased gradually from 5 to 50mg/mL. An intermediate concentration (20mg/mL) resulted in the best separation efficiency. Three capillaries from the set representing low, intermediate, and high slurry concentrations were further used for three-dimensional bed reconstruction by confocal laser scanning microscopy and morphological analysis of the bed structure. Previous studies suggest increased slurry concentrations will result in higher column efficiency due to the suppression of transcolumn bed heterogeneities, but only up to a critical concentration. Too concentrated slurries favour the formation of larger packing voids (reaching the size of the average particle diameter). Especially large voids, which can accommodate particles from>90% of the particle size distribution, are responsible for a decrease in column efficiency at high slurry concentrations. Our work illuminates the increasing difficulty of achieving high bed densities with small, frictional, cohesive particles. As particle size decreases interparticle forces become increasingly important and hinder the ease of particle sliding during column packing. While an optimal slurry concentration is identified with respect to bed morphology and separation efficiency under conditions in this work, our results suggest adjustments of this concentration are required with regard to particle size, surface roughness, column dimensions, slurry liquid, and external effects utilized during the packing process (pressure protocol, ultrasound, electric fields). PMID:26858113

  11. Monolithic silica rod columns for high-efficiency reversed-phase liquid chromatography.

    PubMed

    Miyazaki, Shota; Takahashi, Masakazu; Ohira, Masayoshi; Terashima, Hiroyuki; Morisato, Kei; Nakanishi, Kazuki; Ikegami, Tohru; Miyabe, Kanji; Tanaka, Nobuo

    2011-04-15

    Chromatographic properties of a new type of monolithic silica rod columns were examined. Silica rod columns employed for the study were prepared from tetramethoxysilane, modified with octadecylsilyl moieties, and encased in a stainless-steel protective column with two polymer layers between the silica and the stainless-steel tubing. A 25 cm column provided up to 45,000 theoretical plates for aromatic hydrocarbons, or a minimum plate height of about 5.5 μm, at optimum linear velocity of ca. 2.3 mm/s and back pressure of 7.5 MPa in an acetonitrile-water (80/20, v/v) mobile phase at 40°C. The permeability of the column was similar to that of a column packed with 5 μm particles, with K(F) about 2.4×10(-14) m(2) (based on the superficial linear velocity of the mobile phase), while the plate height value equivalent to that of a column packed with 2.5 μm particles. Generation of 80,000-120,000 theoretical plates was feasible with back pressure below 30 MPa by employing two or three 25 cm columns connected in series. The use of the long columns enabled facile generation of large numbers of theoretical plates in comparison with conventional monolithic silica columns or particulate columns. Kinetic plot analysis indicates that the monolithic columns operated at 30 MPa can provide faster separations than a column packed with totally porous 3-μm particles operated at 40 MPa in a range where the number of theoretical plates (N) is greater than 50,000. PMID:21176839

  12. 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…

  13. 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

  14. 40 CFR 721.4500 - Isopropylamine distillation residues and ethylamine distillation residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Isopropylamine distillation residues and ethylamine distillation residues. 721.4500 Section 721.4500 Protection of Environment... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.4500 Isopropylamine...

  15. Microminiature gas chromatographic column

    NASA Technical Reports Server (NTRS)

    Donaldson, R. W., Jr.

    1972-01-01

    Techniques commonly used for fabrication of integrated circuits are utilized to produce long capillary tubes for microminiature chromatographs. Method involves bonding of flat silicon plate to top of spirally grooved silicon chip to close groove and form capillary column.

  16. A packed bed dehumidifier/regenerator for solar air conditioning with liquid desiccants

    NASA Astrophysics Data System (ADS)

    Factor, H. M.; Grossman, G.

    1980-01-01

    A packed column air-liquid contactor has been studied in application to air dehumidification and regeneration in solar air conditioning with liquid desiccants. A theoretical model has been developed to predict the performance of the device under various operating conditions. Computer simulations based on the model are presented which indicate the practical range of air to liquid flux ratios and associated changes in air humidity and desiccant concentration. An experimental apparatus has been constructed and experiments performed with Monoethylene Glycol (MEG) and Lithium Bromide as desiccants. MEG experiments have yielded inaccurate results and have pointed out some practical problems associated with the use of Glycols. LiBr experiments show very good agreement with the theoretical model. Preheating of the air is shown to greatly enhance desiccant regeneration. The packed column yields good results as a dehumidifier/regenerator, provided pressure drop can be reduced with the use of suitable packing.

  17. Comparison of the volatile composition of Stachys pubescence oils obtained by hydro distillation and steam distillation.

    PubMed

    Biglar, Mahmoud; Ardekani, Mohammad Reza Shams; Khanavi, Mahnaz; Shafiee, Abbas; Rustaiyan, Abdolhossein; Salimpour, Fahimeh; Farjadmand, Fatemeh

    2014-07-01

    The oils obtained by hydrodistillation and steam distillation of the aerial part of Stachys pubescence Ten. was analyzed by GC and GC/MS. Water distilled essential oil of the aerial part of S. pubescence, was rich in fatty acids like hexadecanoic acid and linoleic acid and also benzaldehyde and spathulenol whereas the steam distilled oil of the plant contained hexadecanoic acid, spathulenol and eugenol. Both of oils were rich in fatty acids (36.6 and 27.9%, respectively). Moreover, the content of oxygenated mono and sesquiterpenss were defined higher in steam distilled oil than hydrodistiledd oil (24.5, 17.2 and 6.1, 15.5%, respectively). In conclusion it seems that oxygenated terpenoids were trended to steam distillation method more than hydrodistillation, respectively. PMID:26035946

  18. Radial distribution of the flow velocity, efficiency and concentration in a wide HPLC column

    SciTech Connect

    Farkas, T.; Sepaniak, M.J.; Guiochon, G.

    1997-08-01

    The use of optical fibers in a fluorescence-detection scheme permits the accurate determination of the radial distribution of the transit time, the column efficiency, and the analyte concentration at the exit of a chromatographic axial-compression column (50 mmID). The results obtained demonstrate that the column is not homogeneous, but suggest a nearly cylindrical distribution of the packing density. The average velocity close to the column wall is 7% lower than along its axis and the HETP 25% higher. The lack of homogeneity of the column packing is another source of band broadening not taken into account in chromatography so far. It causes the apparent HETP derived from the conventional elution chromatogram recorded on the bulk eluent to be larger than the local HETP and the band profile to be unsymmetrical with a slight tail reminiscent of kinetic tailing.

  19. 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.

  20. Natural compounds obtained through centrifugal molecular distillation.

    PubMed

    Ito, Vanessa Mayumi; Martins, Patricia Fazzio; Batistella, César Benedito; Maciel Filho, Rubens; Maciel, Maria Regina Wolf

    2006-01-01

    Soybean oil deodorized distillate (SODD) is a byproduct from refining edible soybean oil; however, the deodorization process removes unsaponifiable materials, such as sterols and tocopherols. Tocopherols are highly added value materials. Molecular distillation has large potential to be used in order to concentrate tocopherols, because it uses very low levels of temperatures because of the high vacuum and short operating time for separation and, also, it does not use solvents. However, nowadays, the conventional way to recover tocopherols is carrying out chemical reactions prior to molecular distillation, making the process not so suitable to deal with natural products. The purpose of this work is to use only molecular distillation in order to recover tocopherols from SODD. Experiments were performed in the range of 140-220 degrees C. The feed flow rate varied from 5 to 15 g/min. The objective of this study was to remove the maximum amount of free fatty acids (FFA) and, so, to increase the tocopherol concentration without add any extra component to the system. The percentage of FFA in the distillate stream of the molecular still is larger at low feed flow rates and low evaporator temperatures, avoiding thermal decomposition effects. PMID:16915682

  1. A PROCESS FOR SEPARATING AZEOTROPIC MIXTURES BY EXTRACTIVE AND CONVECTIVE DISTILLATION

    DOEpatents

    Frazer, J.W.

    1961-12-19

    A method is described for separating an azeotrope of carbon tetrachloride and 1,1,2,2-tetrafluorodinitroethane boiling at 60 deg C. The ndethod comnprises, specifically, feeding azeotrope vapors admixed with a non- reactive gas into an extractive distillation column heated to a temperature preferably somewhat above the boiling point of the constant boiling mixture. A solvent, di-n-butylphthalate, is metered into the column above the gas inlet and permitted to flow downward, earrying with it the higher bomling fraction, while the constituent having the lower boiling point passes out of the top of the column with the non-reactive gas and is collected in a nitrogen cold trap. Other solvents which alter the vapor pressure relationship may be substituted. The method is generally applicable to azeotropic mixtures. A number of specific mixtures whicb may be separated are disclosed. (AEC)

  2. Comparison of Advanced Distillation Control Methods, Final Technical Report

    SciTech Connect

    Dr. James B. Riggs

    2000-11-30

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to evaluate configuration selections for single-ended and dual-composition control, as well as to compare conventional and advanced control approaches. In addition, a simulator of a main fractionator was used to compare the control performance of conventional and advanced control. For each case considered, the controllers were tuned by using setpoint changes and tested using feed composition upsets. Proportional Integral (PI) control performance was used to evaluate the configuration selection problem. For single ended control, the energy balance configuration was found to yield the best performance. For dual composition control, nine configurations were considered. It was determined that the use of dynamic simulations is required in order to identify the optimum configuration from among the nine possible choices. The optimum configurations were used to evaluate the relative control performance of conventional PI controllers, MPC (Model Predictive Control), PMBC (Process Model-Based Control), and ANN (Artificial Neural Networks) control. It was determined that MPC works best when one product is much more important than the other, while PI was superior when both products were equally important. PMBC and ANN were not found to offer significant advantages over PI and MPC. MPC was found to outperform conventional PI control for the main fractionator. MPC was applied to three industrial columns: one at Phillips Petroleum and two at Union Carbide. In each case, MPC was found to significantly outperform PI controls. The major advantage of the MPC controller is its ability to effectively handle a complex set of constraints and control objectives.

  3. 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.

  4. Entanglement distillation protocols and number theory

    SciTech Connect

    Bombin, H.; Martin-Delgado, M.A.

    2005-09-15

    We show that the analysis of entanglement distillation protocols for qudits of arbitrary dimension D benefits from applying basic concepts from number theory, since the set Z{sub D}{sup n} associated with Bell diagonal states is a module rather than a vector space. We find that a partition of Z{sub D}{sup n} into divisor classes characterizes the invariant properties of mixed Bell diagonal states under local permutations. We construct a very general class of recursion protocols by means of unitary operations implementing these local permutations. We study these distillation protocols depending on whether we use twirling operations in the intermediate steps or not, and we study them both analytically and numerically with Monte Carlo methods. In the absence of twirling operations, we construct extensions of the quantum privacy algorithms valid for secure communications with qudits of any dimension D. When D is a prime number, we show that distillation protocols are optimal both qualitatively and quantitatively.

  5. Superadditivity of distillable entanglement from quantum teleportation

    SciTech Connect

    Bandyopadhyay, Somshubhro; Roychowdhury, Vwani

    2005-12-15

    We show that the phenomenon of superadditivity of distillable entanglement observed in multipartite quantum systems results from the consideration of states created during the execution of the standard end-to-end quantum teleportation protocol [and a few additional local operations and classical communication (LOCC) steps] on a linear chain of singlets. Some of these intermediate states are tensor products of bound entangled (BE) states, and hence, by construction possess distillable entanglement, which can be unlocked by simply completing the rest of the LOCC operations required by the underlying teleportation protocol. We use this systematic approach to construct both new and known examples of superactivation of bound entanglement, and examples of activation of BE states using other BE states. A surprising outcome is the construction of noiseless quantum relay channels with no distillable entanglement between any two parties, except for that between the two end nodes.

  6. 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

  7. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  8. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  9. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  10. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  11. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  12. Preprototype Vapor Compression Distillation Subsystem development

    NASA Technical Reports Server (NTRS)

    Thompson, C. D.; Ellis, G. S.; Schubert, F. H.

    1981-01-01

    Vapor Compression Distillation (VCD) has evolved as the most promising approach to reclaim potable water from wastewater for future long-term manned space missions. Life Systems, Inc. (LSI), working with NASA, has developed a preprototype Vapor Compression Distillation Subsystem (VCDS) which processes wastewater at 1.4 kg/h. The preprototype unit weighs 143 kg, occupies a volume of 0.47 cu m, and will reclaim 96 percent of the available wastewater. This unit has been tested by LSI and is scheduled for further testing at NASA-JSC. This paper presents the preprototype VCDS design, configuration, performance data, test results and flight system projections.

  13. 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.

  14. Classic papers in Solar Energy: Solar distillation

    SciTech Connect

    Howe, E.D.

    1990-06-01

    The following Classic Paper was presented by Professor Howe at the first international Conference on Solar Energy at Tucson, Arizona, USA in 1955. That conference was sponsored by the Association of Applied solar Energy (AFASE), the precursor of ISES. Although this paper does not represent the many developments in solar distillation later applied by Professor Howe in the South Pacific, it is a classic paper because it presents Professor Howe's pioneering work in setting up the Seawater Conversion Laboratory in Richmond for the University of California at Berkeley, US. The research of Professor Howe and his colleagues at the Seawater Conversion Laboratory formed the foundation of contemporary solar energy desalination and distillation systems.

  15. Eruption column physics

    SciTech Connect

    Valentine, G.A.

    1997-03-01

    In this paper the author focuses on the fluid dynamics of large-scale eruption columns. The dynamics of these columns are rooted in multiphase flow phenomena, so a major part of the paper sets up a foundation on that topic that allows one to quickly assess the inherent assumptions made in various theoretical and experimental approaches. The first part is centered on a set of complex differential equations that describe eruption columns, but the focus is on a general understanding of important physical processes rather than on the mathematics. The author discusses briefly the relative merits and weaknesses of different approaches, emphasizing that the largest advances in understanding are made by combining them. He then focuses on dynamics of steady eruption columns and then on transient phenomena. Finally he briefly reviews the effects of varying behavior of the ambient medium through which an eruption column moves. These final sections will emphasize concepts and a qualitative understanding of eruption dynamics. This paper relies on principles of continuum mechanics and transport processes but does not go into detail on the development of those principles. 36 refs., 36 figs., 3 tabs.

  16. 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

  17. 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.

  18. Packing nanomechanics of viral genomes

    NASA Astrophysics Data System (ADS)

    Iber, A. Å.; Dragar, M.; Parsegian, V. A.; Podgornik, R.

    2008-07-01

    We investigate the osmotic equilibrium between a bulk polyethylene glycol (PEG) solution and DNA tightly packed in a spherical capsid. We base our analysis on the equations of thermodynamic equilibrium in terms of osmotic pressure. The equality between external osmotic pressure of PEG and osmotic pressure of tightly packed DNA gives us the DNA encapsidation curves. In this way we directly connect the wealth of existing osmotic pressure data for DNA in the bulk with the DNA encapsidation curves within small viral capsids. Specific calculations are made for a monovalent salt, Na+ -DNA and a divalent salt, Mn2+ -DNA that have quite different DNA encapsidation behaviors. The main conclusion of our work is that bending energy of DNA is of minor importance regarding the encapsidated DNA length, but has a non-negligible influence on the density distribution of DNA within the capsid.

  19. Ecology of southern ocean pack ice.

    PubMed

    Brierley, Andrew S; Thomas, David N

    2002-01-01

    Around Antarctica the annual five-fold growth and decay of sea ice is the most prominent physical process and has a profound impact on marine life there. In winter the pack ice canopy extends to cover almost 20 million square kilometres--some 8% of the southern hemisphere and an area larger than the Antarctic continent itself (13.2 million square kilometres)--and is one of the largest, most dynamic ecosystems on earth. Biological activity is associated with all physical components of the sea-ice system: the sea-ice surface; the internal sea-ice matrix and brine channel system; the underside of sea ice and the waters in the vicinity of sea ice that are modified by the presence of sea ice. Microbial and microalgal communities proliferate on and within sea ice and are grazed by a wide range of proto- and macrozooplankton that inhabit the sea ice in large concentrations. Grazing organisms also exploit biogenic material released from the sea ice at ice break-up or melt. Although rates of primary production in the underlying water column are often low because of shading by sea-ice cover, sea ice itself forms a substratum that provides standing stocks of bacteria, algae and grazers significantly higher than those in ice-free areas. Decay of sea ice in summer releases particulate and dissolved organic matter to the water column, playing a major role in biogeochemical cycling as well as seeding water column phytoplankton blooms. Numerous zooplankton species graze sea-ice algae, benefiting additionally because the overlying sea-ice ceiling provides a refuge from surface predators. Sea ice is an important nursery habitat for Antarctic krill, the pivotal species in the Southern Ocean marine ecosystem. Some deep-water fish migrate to shallow depths beneath sea ice to exploit the elevated concentrations of some zooplankton there. The increased secondary production associated with pack ice and the sea-ice edge is exploited by many higher predators, with seals, seabirds and whales aggregating there. As a result, much of the Southern Ocean pelagic whaling was concentrated at the edge of the marginal ice zone. The extent and duration of sea ice fluctuate periodically under the influence of global climatic phenomena including the El Niño Southern Oscillation. Life cycles of some associated species may reflect this periodicity. With evidence for climatic warming in some regions of Antarctica, there is concern that ecosystem change may be induced by changes in sea-ice extent. The relative abundance of krill and salps appears to change interannually with sea-ice extent, and in warm years, when salps proliferate, krill are scarce and dependent predators suffer severely. Further research on the Southern Ocean sea-ice system is required, not only to further our basic understanding of the ecology, but also to provide ecosystem managers with the information necessary for the development of strategies in response to short- and medium-term environmental changes in Antarctica. Technological advances are delivering new sampling platforms such as autonomous underwater vehicles that are improving vastly our ability to sample the Antarctic under sea-ice environment. Data from such platforms will enhance greatly our understanding of the globally important Southern Ocean sea-ice ecosystem. PMID:12154613

  20. Kinetic and reactor models for HDT of middle distillates

    SciTech Connect

    Cotta, R.M.; Filho, R.M.

    1996-12-31

    Hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) of middle distillates over a commercial Ni-Mo/y-Al{sub 2}O{sub 3} has been studied under wide operating conditions just as 340 to 380{degrees}C and 38 to 98 atm. A Power Law model was presented to each one of those reactions. The parameters of kinetic equations were estimated solving the ordinary differential equations by the 4 order Runge-Kutta-Gill algorithm and Marquardt method for searching of set of kinetic parameters (kinetic constants as well as the orders of reactions). An adiabatic diesel hydrotreating trickle-bed reactor packed with the same catalyst was simulated numerically in order to check up the behavior of this specific reaction system. One dimensional pseudo-homogeneous model was used in this work. For each feed, the mass and energy balance equations were integrated along the length of the catalytic bed using the 4th Runge-Kutta-Gill method. The performance of two industrial reactors was checked. 5 refs., 2 tabs.

  1. Semi-micro-monolithic columns using macroporous silica rods with improved performance.

    PubMed

    Morisato, Kei; Miyazaki, Shota; Ohira, Masayoshi; Furuno, Masahiro; Nyudo, Masahiko; Terashima, Hiroyuki; Nakanishi, Kazuki

    2009-10-30

    Monolithic silica columns in semi-micro-format have been synthesized using poly(acrylic acid) as a phase-separation inducer via a sol-gel route. The absence of a thick skin layer accompanied by deformation of the micrometer-sized gelling skeletons on the outermost part of the macroporous silica rod contributed to improve the efficiency of monolithic silica columns as thick as 2.4 mm in diameter. The kinetic plot analysis revealed that monolithic silica columns with macropore diameter of 1 microm and skeleton thickness of 1 microm with decreased macroporosity behave similarly to columns packed with 3 microm particles with slightly lower back pressure. PMID:19500793

  2. 7 CFR 966.11 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Definitions § 966.11 Pack. Pack means any of the packs of tomatoes as defined and set forth in the United States Standards for Fresh Tomatoes issued by the United States Department of Agriculture (§§...

  3. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cold pack. 890.5700 Section 890.5700 Food and... PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack is a device intended for medical purposes that consists of a compact fabric...

  4. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cold pack. 890.5700 Section 890.5700 Food and... PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack is a device intended for medical purposes that consists of a compact fabric...

  5. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cold pack. 890.5700 Section 890.5700 Food and... PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification. A cold pack is a device intended for medical purposes that consists of a compact fabric...

  6. 7 CFR 920.13 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Pack. 920.13 Section 920.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Definitions § 920.13 Pack. Pack means the...

  7. 7 CFR 51.1527 - Standard pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Fresh Plums and Prunes Standard Pack § 51... the approved and recognized methods. (2) The plums or prunes in the top layer of any package shall be...” means that the plums or prunes packed in loose or volume filled containers are packed within 1 inch...

  8. 7 CFR 51.1527 - Standard pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Fresh Plums and Prunes Standard Pack § 51... the approved and recognized methods. (2) The plums or prunes in the top layer of any package shall be...” means that the plums or prunes packed in loose or volume filled containers are packed within 1 inch...

  9. 7 CFR 966.11 - Pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Definitions § 966.11 Pack. Pack means any of the packs of tomatoes as defined and set forth in the United States Standards for Fresh Tomatoes issued by the United States Department of Agriculture (§§...

  10. 7 CFR 966.11 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Definitions § 966.11 Pack. Pack means any of the packs of tomatoes as defined and set forth in the United States Standards for Fresh Tomatoes issued by the United States Department of Agriculture (§§...

  11. 7 CFR 966.11 - Pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Definitions § 966.11 Pack. Pack means any of the packs of tomatoes as defined and set forth in the United States Standards for Fresh Tomatoes issued by the United States Department of Agriculture (§§...

  12. 7 CFR 966.11 - Pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Definitions § 966.11 Pack. Pack means any of the packs of tomatoes as defined and set forth in the United States Standards for Fresh Tomatoes issued by the United States Department of Agriculture (§§...

  13. Diffusion in Jammed Particle Packs

    NASA Astrophysics Data System (ADS)

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

    2015-08-01

    Using random walk simulations we explore diffusive transport through monodisperse sphere packings over a range of packing fractions ? in the vicinity of the jamming transition at ?c . Various diffusion properties are computed over several orders of magnitude in both time and packing pressure. Two well-separated regimes of normal "Fickian" diffusion, where the mean squared displacement is linear in time, are observed. The first corresponds to diffusion inside individual spheres, while the latter is the long-time bulk diffusion. The intermediate anomalous diffusion regime and the long-time value of the diffusion coefficient are both shown to be controlled by particle contacts, which in turn depend on proximity to ?c . The time required to recover normal diffusion t* scales as (? -?c)-0.5 and the long-time diffusivity D?(? -?c)0.5 , or D?1 /t* . It is shown that the distribution of mean first passage times associated with the escape of random walkers between neighboring particles controls both t* and D? in the limit ? ??c.

  14. Column technology and detection for capillary electroseparation techniques

    NASA Astrophysics Data System (ADS)

    Fermier, Adam M.

    1998-07-01

    Capillary separation techniques offer many advantages over conventional separation technology because of the small column inner diameters, including small sample volumes, increased mass sensitivity, and high separation efficiencies. However, there are several practical considerations that must be addressed when using capillary columns. Herein, two such considerations are addressed-detection and column technology. First, electrochemical detection was studied as a detection mode for capillary electrophoresis (CE). Detection of the small zones of carbohydrates and amino acids were performed after separation by CE. An inexpensive capillary-electrode holder was developed to facilitate alignment between the separation capillary and the electrode. The capillary-electrode holder provided a more time efficient means to align the separation capillary and the detection electrode. Second, the difficulty of packing capillary columns is addressed. We devised a method which uses centripetal forces to carry the particles into the capillary column, facilitating packing. It was noted that the highest impact speed resulted in better performance for columns used in capillary electrochromatography. The relationship between performance and column diameter was studied between 75 μm and 31 μm i.d. The efficiency of the smaller bore columns was greater and the smaller column proved to be more rugged. A method was also devised to measure the porosity of the columns from the observed resistance of the column. Porosity measurements for these columns ranged between 0.4 and 0.6. Throughout this work, steps were taken to understand fundamentally and experimentally the limits of chromatography in an effort to approach these limits. Of particular interest is the reduction of the particle diameter in liquid chromatography. To this end, electrochromatographic flow studies in submicron beds were conducted to investigate the effect of buffer and organic concentrations in such flows. Both, primary and secondary electroviscous effects were observed. Primary electroviscous effects are a function of the applied field and were observed by a decrease in the overall electroosmotic mobility as a function of the applied field. Secondary electroviscous effects, or double layer overlapping, caused the flow to decrease and were observed by lowering the electrolyte concentration to satisfy a /kappa a<10/ (~1/ mM).

  15. Fundamental Studies on Two-Phase Gas-Liquid Flows Through Packed Beds in Microgravity

    NASA Technical Reports Server (NTRS)

    Balakotaiah, Vemuri; McCready, Mark J.; Motil, Brian J.

    2002-01-01

    In the typical operation of a packed-bed reactor, gas and liquid flow simultaneously through a fixed bed of solid particles. Depending on the application, the particles can be of various shapes and sizes and provide for intimate contact and high rates of transport between the phases needed to sustain chemical or biological reactions. The packing may also serve as either a catalyst or as a support for growing biological material. NASA has flown two of these packed-bed systems in a microgravity environment with limited or no success. The goal of this research is to develop models (with scale-up capability) needed for the design of the physicochemical equipment to carry out these unit operations in microgravity. New insight will also lead to improvements in normal gravity operations. Our initial experiment was flown using an existing KC-135 two-phase flow rig with a modified test section. The test section is a clear polycarbonate rectangular column with a depth of 2.54 cm, a width of 5.08 cm, and 60 cm long. The column was randomly packed with spherical glass beads by slowly dropping the beads into the bed. Even though care was taken in handling the column after it was filled with packing, the alternating high and low gravity cycles with each parabola created a slightly tighter packed bed than is typically reported for this type. By the usual method of comparing the weight difference of a completely dry column versus a column filled with water, the void fraction was found to be .345 for both sizes of beads used. Five flush mounted differential pressure transducers are spaced at even intervals with the first location 4 cm from the inlet port and the subsequent pressure transducers spaced at 13 cm intervals along the column. Differential pressure data was acquired at 1000 Hz to adequately observe pulse formation and characteristics. Visual images of the flow were recorded using a high-speed SVHS system at 500 frames per second. Over 250 different test conditions were evaluated along with a companion set of tests in normal gravity. The flow rates, fluid properties and packing properties were selected to provide a range of several orders-of-magnitude for the important dimensionless parameters. Additional information is included in the original extended abstract.

  16. Distillation Calculations with a Programmable Calculator.

    ERIC Educational Resources Information Center

    Walker, Charles A.; Halpern, Bret L.

    1983-01-01

    Describes a three-step approach for teaching multicomponent distillation to undergraduates, emphasizing patterns of distribution as an aid to understanding the separation processes. Indicates that the second step can be carried out by programmable calculators. (A more complete set of programs for additional calculations is available from the

  17. 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 ...

  18. Holoprosencephaly: A mythologic and teratologic distillate.

    PubMed

    Cohen, M Michael

    2010-02-15

    This review of holoprosencephaly provides a mythologic and teratologic distillate of the subject under the following headings: Babylonian tablets; Greek mythology; pictures from the 16th through the 20th Centuries; 19th Century teratology; history of more modern concepts and their terminologies; and ocean-going ships named "Cyclops." PMID:20082455

  19. Distillation Calculations with a Programmable Calculator.

    ERIC Educational Resources Information Center

    Walker, Charles A.; Halpern, Bret L.

    1983-01-01

    Describes a three-step approach for teaching multicomponent distillation to undergraduates, emphasizing patterns of distribution as an aid to understanding the separation processes. Indicates that the second step can be carried out by programmable calculators. (A more complete set of programs for additional calculations is available from the…

  20. Distillers Grains: Production, Properties and Utilization (Book)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The book, Distillers Grains: Production, Properties and Utilization, brings together cutting edge information on many aspects of DDGS. It consists of six major sections, having 26 chapters in total. Section 1 has six chapters and covers introduction, perspectives, history, structure and compositio...

  1. 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

  2. Determination of the boiling-point distribution by simulated distillation from n-pentane through n-tetratetracontane in 70 to 80 seconds.

    PubMed

    Lubkowitz, Joaquin A; Meneghini, Roberto I

    2002-01-01

    This work presents the carrying out of boiling-point distributions by simulated distillation with direct-column heating rather than oven-column heating. Column-heating rates of 300 degrees C/min are obtained yielding retention times of 73 s for n-tetratetracontane. The calibration curves of the retention time versus the boiling point, in the range of n-pentane to n-tetratetracontane, are identical to those obtained by slower oven-heating rates. The boiling-point distribution of the reference gas oil is compared with that obtained with column oven heating at rates of 15 to 40 degrees C/min. The results show boiling-point distribution values nearly the same (1-2 degrees F) as those obtained with oven column heating from the initial boiling point to 80% distilled off. Slightly higher differences are obtained (3-4 degrees F) for the 80% distillation to final boiling-point interval. Nonetheless, allowed consensus differences are never exceeded. Precision of the boiling-point distributions (expressed as standard deviations) are 0.1-0.3% for the data obtained in the direct column-heating mode. PMID:12049156

  3. HEAT TRANSFER ANALYSIS FOR ION-EXCHANGE COLUMN SYSTEM

    SciTech Connect

    Lee, S.; King, W.

    2011-05-23

    Models have been developed to simulate the thermal characteristics of Crystalline Silicotitanate (CST) ion exchange media fully loaded with radioactive cesium in a column configuration and distributed within a waste storage tank. This work was conducted to support the Small Column Ion Exchange (SCIX) program which is focused on processing dissolved, high-sodium salt waste for the removal of specific radionuclides (including Cs-137, Sr-90, and actinides) within a High Level Waste (HLW) storage tank at the Savannah River Site. The SCIX design includes CST columns inserted and supported in the tank top risers for cesium removal. Temperature distributions and maximum temperatures across the column were calculated with a focus on process upset conditions. A two-dimensional computational modeling approach for the in-column ion-exchange domain was taken to include conservative, bounding estimates for key parameters such that the results would provide the maximum centerline temperatures achievable under the design configurations using a feed composition known to promote high cesium loading on CST. The current full-scale design for the CST column includes one central cooling pipe and four outer cooling tubes. Most calculations assumed that the fluid within the column was stagnant (i.e. no buoyancy-induced flow) for a conservative estimate. A primary objective of these calculations was to estimate temperature distributions across packed CST beds immersed in waste supernate or filled with dry air under various accident scenarios. Accident scenarios evaluated included loss of salt solution flow through the bed, inadvertent column drainage, and loss of active cooling in the column. The modeling results demonstrate that the baseline design using one central and four outer cooling tubes provides a highly efficient cooling mechanism for reducing the maximum column temperature.

  4. Dense Regular Packings of Irregular Nonconvex Particles

    NASA Astrophysics Data System (ADS)

    de Graaf, Joost; van Roij, René; Dijkstra, Marjolein

    2011-10-01

    We present a new numerical scheme to study systems of nonconvex, irregular, and punctured particles in an efficient manner. We employ this method to analyze regular packings of odd-shaped bodies, both from a nanoparticle and from a computational geometry perspective. Besides determining close-packed structures for 17 irregular shapes, we confirm several conjectures for the packings of a large set of 142 convex polyhedra and extend upon these. We also prove that we have obtained the densest packing for both rhombicuboctahedra and rhombic enneacontrahedra and we have improved upon the packing of enneagons and truncated tetrahedra.

  5. Slurry concentration effects on the bed morphology and separation efficiency of capillaries packed with sub-2 μm particles.

    PubMed

    Bruns, Stefan; Franklin, Edward G; Grinias, James P; Godinho, Justin M; Jorgenson, James W; Tallarek, Ulrich

    2013-11-29

    Transcolumn dispersion limitations on the separation efficiency of chromatographic columns suggest the need for packing methods that increase bed homogeneity and minimize potential wall effects. Here we address the influence of the slurry concentration in the slurry packing process on the resulting morphology and separation efficiency of ultrahigh-pressure liquid chromatography capillary columns.30–75 μm i.d. capillaries were packed with fully porous 0.9, 1.7, and 1.9 μm bridged-ethyl hybrid particles and 1.9 μm Kinetex core–shell particles. Capillaries prepared with higher slurry concentrations(20–100 mg/mL) showed higher separation efficiencies than those prepared using a low slurry con-centration (2–3 mg/mL). The effect is explained by an analysis of transcolumn bed heterogeneities in three-dimensional reconstructions acquired from the packed capillaries using confocal laser scanning microscopy. The three-dimensional analysis of porosity distributions and local particle size illustrates that beds packed with higher slurry concentrations suppress particle size segregation, however, at the expense of a larger amount of packing voids. In core–shell packings, where only few packing voids were found, the higher slurry concentration allowed for an additional densification of the bed’s wall region, as revealed by a radial analysis of the mean particle distances. Overall, wall effects are attenuated in packed columns prepared with both wide and narrow particle size distributions, which will allow for improved chromatographic performance. PMID:24354004

  6. Catalytically enhanced packed tower scrubbing

    SciTech Connect

    Stitt, E.H.; Taylor, F.J.; Kelly, K.

    1996-12-31

    An enhanced wet scrubbing process for the treatment of gas streams containing odours and low level VOC`s is presented. It comprises essentially a single scrubbing column and a fixed bed catalytic reactor through which the dilute alkaline bleach scrubbing liquor is recirculated. The process has significant cost advantages over conventional chemical scrubbing technology, and copes well with peaks in odour levels. Traditional bleach scrubbing, and the improvements in process chemistry and the flowsheet afforded by inclusion of the catalyst, are discussed. The catalyst enables many of the well known problems associated with bleach scrubbing to be overcome, and facilitates odour removal efficiencies of greater than 99% in a single column. Pilot plant data from trials on sewage treatment works are presented. These show clearly the ability of the catalytically enhanced process to achieve sulphide and odour removals in excess of 99% in the single column. Case studies of some of the existing commercial installations are given, indicating the wide range of applications, industries and scale of the installed units. Comparative data are presented, measured on a commercial unit for the conventional operation of a bleach scrubber, and with the retrofitted catalyst in use. These data show clearly the benefits of the catalytic process in terms of removal efficiencies; and hence by inference also in equipment size and costs. The catalytic process is also shown to achieve very high removal efficiencies of organo-sulphides in a single column. 8 refs., 3 figs., 10 tabs.

  7. 27 CFR 19.322 - Distillates containing extraneous substances.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... bonded wine cellar shall be in accordance with the provisions of 27 CFR part 240. (Sec. 201, Pub. L. 85... therein for fermentation of wine to be used as distilling material at the distilled spirits plant...

  8. 27 CFR 17.162 - Receipt of distilled spirits.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... distilled spirits plant. If spirits are received in a tank car or tank truck, and the result of the... the distilled spirits plant that paid or determined the tax, the manufacturer shall retain the...

  9. 27 CFR 17.162 - Receipt of distilled spirits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... distilled spirits plant. If spirits are received in a tank car or tank truck, and the result of the... the distilled spirits plant that paid or determined the tax, the manufacturer shall retain the...

  10. 27 CFR 17.162 - Receipt of distilled spirits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... distilled spirits plant. If spirits are received in a tank car or tank truck, and the result of the... the distilled spirits plant that paid or determined the tax, the manufacturer shall retain the...

  11. 27 CFR 17.162 - Receipt of distilled spirits.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... distilled spirits plant. If spirits are received in a tank car or tank truck, and the result of the... the distilled spirits plant that paid or determined the tax, the manufacturer shall retain the...

  12. 27 CFR 17.162 - Receipt of distilled spirits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... distilled spirits plant. If spirits are received in a tank car or tank truck, and the result of the... the distilled spirits plant that paid or determined the tax, the manufacturer shall retain the...

  13. 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…

  14. A Column Dispersion Experiment.

    ERIC Educational Resources Information Center

    Corapcioglu, M. Y.; Koroglu, F.

    1982-01-01

    Crushed glass and a Rhodamine B solution are used in a one-dimensional optically scanned column experiment to study the dispersion phenomenon in porous media. Results indicate that the described model gave satisfactory results and that the dispersion process in this experiment is basically convective. (DC)

  15. 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

  16. 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.

  17. 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

  18. Monolithic silica columns for high-efficiency separations by high-performance liquid chromatography.

    PubMed

    Ishizuka, Norio; Kobayashi, Hiroshi; Minakuchi, Hiroyoshi; Nakanishi, Kazuki; Hirao, Kazuyuki; Hosoya, Ken; Ikegami, Tohru; Tanaka, Nobuo

    2002-06-25

    Generation of a large number of theoretical plates was attempted by capillary HPLC. Monolithic silica columns having small skeletons (ca. 2 microm) and large through-pores (ca. 8 microm) were prepared by a sol-gel method in a fused-silica capillary (50 microm I.D.), and derivatized to C18 phase by on-column reaction. High external porosity (>80%) and large through-pores resulted in high permeability (K= 1.2 x 10(-2) m2). The monolithic silica column in the capillary produced a plate height of about 12 microm in 80% acetonitrile at a linear velocity of 1 mm/s. Separation impedance, E value, was found to be as low as 200, that was about an order of magnitude lower than reported values for conventional columns packed with 5 microm particles. Reproducibility of preparation within +/- 15% was obtained for column efficiency and for pressure drop. It was possible to generate 100,000 plates by using a 130-cm column at very low pressure (<7 kg/cm2). A considerable decrease in column efficiency was observed at high linear velocity, and for solutes with large retention factors due to the slow mobile-phase mass transfer in the large through-pores. The monolithic silica columns, however, showed performance beyond the limit of conventional particle-packed columns in HPLC under favorable conditions. PMID:12150566

  19. Distilling one-qubit magic states into Toffoli states

    NASA Astrophysics Data System (ADS)

    Eastin, Bryan

    2013-03-01

    For certain quantum architectures and algorithms, most of the required resources are consumed during the distillation of one-qubit magic states for use in performing Toffoli gates. I show that the overhead for magic-state distillation can be reduced by merging distillation with the implementation of Toffoli gates. The resulting routine distills eight one-qubit magic states directly to a Toffoli state, which can be used without further magic to perform a Toffoli gate.

  20. Interpolation of recurrence and hashing entanglement distillation protocols

    SciTech Connect

    Vollbrecht, Karl Gerd H.; Verstraete, Frank

    2005-06-15

    We construct interesting entanglement distillation protocols by interpolating between the recurrence and hashing protocols. This leads to asymptotic two-way distillation protocols, resulting in an improvement of the distillation rate for all mixed Bell diagonal entangled states, even for the ones with very high fidelity. We also present a method for how entanglement-assisted distillation protocol can be converted into nonentanglement-assisted protocols with the same yield.

  1. Efficiency of supercritical fluid chromatography columns in different thermal environments.

    PubMed

    Kaczmarski, Krzysztof; Poe, Donald P; Tarafder, Abhijit; Guiochon, Georges

    2013-05-24

    The efficiency of a packed column eluted with supercritical carbon dioxide at 323K and outlet pressures from 90 to 150bar was studied with the column in two different thermal environments. The 150mm×2.0mm ID stainless steel column was packed with spherical 5-μm porous silica particles with a covalently bonded nonpolar stationary phase, and the test solutes were normal alkanes. When operated in a convective air bath the column exhibited severe efficiency losses when its outlet pressure was below 120bar. The efficiency of the same column enclosed in a shell made of foam insulation was restored at low outlet pressures down to 100bar. The van Deemter plots showed an abnormal dependence of the plate height (HETP) on the flow rate at low outlet pressures, exhibiting a maximum in the HETP at flow rates around 1mL/min and a 20-bar pressure drop. The large efficiency losses at low outlet pressures are due to radial temperature gradients associated with enthalpic expansion and cooling of the mobile phase. The separations were simulated by a numerical model that accounts for axial and radial gradients in the temperature and density along the column. The abnormal van Deemter plots arise from competing processes affecting the radial distribution of the solute migration velocity along the column. The negative impact on efficiency is greatest when the density profile of the mobile phase along the column is close to the critical isopycnic line. The efficiency improves at increased flow rates because of increased cooling at larger pressure drops and increased density along the entire length of the column. The model predicts the unusual trends in the van Deemter plots, but the calculated results at low outlet pressures are strongly influenced by small variations in the porosity distribution in the column, limiting the accuracy of the predicted HETP values. In spite of these difficulties, the model has enabled a detailed analysis of the effects of temperature, pressure and flow rate on the thermal properties of the mobile phase, and their impact on the radial distribution of the solute velocities along the column. This work provides a better appreciation of the factors that cause excess efficiency loss at low outlet pressures, a phenomenon that lacked a convincing explanation for over 40 years. Finally, a simplified form of the model, which ignores the radial gradients, provided accurate results only at the highest outlet pressure. Calculations done by the simplified model are much faster, and it can be recommended for simulation of SFC processes at sufficiently high outlet pressures. PMID:23598158

  2. Fiber separation from distillers dried grains with solubles using a larger elutriation apparatus and use of fiber as a feedstock for corn fiber gum production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In an earlier study, the combination of sieving and elutriation (air flow) was found to be effective in separating fiber from distillers dried grains with solubles (DDGS); the elutriation column diameter used was 63 mm. Larger quantities of fractions were needed for carrying out studies on producti...

  3. 40 CFR 721.9635 - Terpene residue distillates.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Terpene residue distillates. 721.9635... Substances § 721.9635 Terpene residue distillates. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as terpene residue distillates (PMN...

  4. Antioxidant Activity of Phytochemicals from Dried Distillers Grain Oil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A distillate was obtained by molecular distillation of oil extracted from distiller’s dried grains (DDG). The dried distiller’s grains distillate (DDGD) contained phytosterols, steryl ferulates, tocopherols, tocotrienols, and carotenoids. DDGD was tested for its impact on the oxidative stability i...

  5. 27 CFR 19.669 - Distilled spirits taxes.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., DEPARTMENT OF THE TREASURY ALCOHOL DISTILLED SPIRITS PLANTS Distilled Spirits for Fuel Use Liability for... an alcohol fuel plant if the spirits are withdrawn exclusively for fuel use in accordance with this... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Distilled spirits...

  6. 27 CFR 19.669 - Distilled spirits taxes.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., DEPARTMENT OF THE TREASURY ALCOHOL DISTILLED SPIRITS PLANTS Distilled Spirits for Fuel Use Liability for... an alcohol fuel plant if the spirits are withdrawn exclusively for fuel use in accordance with this... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Distilled spirits...

  7. 27 CFR 19.307 - Distillates containing extraneous substances.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Distillates containing extraneous substances. 19.307 Section 19.307 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... for use in fermentation of wine to be used as distilling material at the distilled spirits plant...

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

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Use of distillates containing aldehydes. 24.183 Section 24.183 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... the fermentation of wine and then returned to the distilled spirits plant from which distillates...

  9. 27 CFR 19.307 - Distillates containing extraneous substances.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Distillates containing extraneous substances. 19.307 Section 19.307 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... for use in fermentation of wine to be used as distilling material at the distilled spirits plant...

  10. 40 CFR 721.9635 - Terpene residue distillates.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Terpene residue distillates. 721.9635... Substances § 721.9635 Terpene residue distillates. Link to an amendment published at 79 FR 34638, June 18... identified generically as terpene residue distillates (PMN P-96-897) is subject to reporting under...

  11. 40 CFR 721.9635 - Terpene residue distillates.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Terpene residue distillates. 721.9635... Substances § 721.9635 Terpene residue distillates. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as terpene residue distillates (PMN...

  12. Antioxidant activity of phytochemicals from dried distillers grain oil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A distillate was obtained by molecular distillation of oil extracted from distiller’s dried grains (DDG). The dried distiller’s grains distillate (DDGD) contained phytosterols, steryl ferulates, tocopherols, tocotrienols, and carotenoids. DDGD was tested for its impact on the oxidative stability in...

  13. 7 CFR 160.9 - Destructively distilled wood turpentine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Destructively distilled wood turpentine. 160.9 Section... REGULATIONS AND STANDARDS FOR NAVAL STORES General § 160.9 Destructively distilled wood turpentine. The designation “destructively distilled wood turpentine” shall refer to the kind of spirits of...

  14. 7 CFR 160.9 - Destructively distilled wood turpentine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Destructively distilled wood turpentine. 160.9 Section... REGULATIONS AND STANDARDS FOR NAVAL STORES General § 160.9 Destructively distilled wood turpentine. The designation “destructively distilled wood turpentine” shall refer to the kind of spirits of...

  15. 7 CFR 160.9 - Destructively distilled wood turpentine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Destructively distilled wood turpentine. 160.9 Section... REGULATIONS AND STANDARDS FOR NAVAL STORES General § 160.9 Destructively distilled wood turpentine. The designation “destructively distilled wood turpentine” shall refer to the kind of spirits of...

  16. 7 CFR 160.9 - Destructively distilled wood turpentine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Destructively distilled wood turpentine. 160.9 Section... REGULATIONS AND STANDARDS FOR NAVAL STORES General § 160.9 Destructively distilled wood turpentine. The designation “destructively distilled wood turpentine” shall refer to the kind of spirits of...

  17. 7 CFR 160.9 - Destructively distilled wood turpentine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Destructively distilled wood turpentine. 160.9 Section... REGULATIONS AND STANDARDS FOR NAVAL STORES General § 160.9 Destructively distilled wood turpentine. The designation “destructively distilled wood turpentine” shall refer to the kind of spirits of...

  18. Determination of the column hold-up volume in supercritical fluid chromatography using nitrous-oxide.

    PubMed

    Vajda, Péter; Guiochon, Georges

    2013-09-27

    This study introduces a new tracer that is useful for the determination of the hold-up time or volume of packed columns, particularly of those used in supercritical fluid chromatography. The thermodynamic void volume of three columns packed with different adsorbents were determined using the weight difference method. These void volumes were used as the reference point in the further discussion. The hold-up volumes of these columns were determined under dynamic conditions, using nitrous oxide dissolved in methanol as the hold-up time marker. Changes in the hold-up volumes of these columns were monitored during changes of the volumetric flow rate of pure supercritical carbon dioxide and of dilute mixtures of organic modifier and supercritical carbon dioxide. The results suggest significant methanol enrichment on the adsorbent surface. PMID:23972457

  19. Coaltar fractionation with a wide range of fractions. 3. Removal of high-boiling fractions from coaltar distillate

    SciTech Connect

    Gogoleva, T.Ya.; Krasulya, M.A.; Achkasova, G.G.; Butsinskaya, L.I.

    1992-12-31

    The high-boiling fractions of coaltar include the anthracene, phenanthrene-carbazole, fluoranthene, pyrene and chrysene cuts. At present, the anthracene fraction, containing 6.3-9.4% anthracene, is taken directly from the coaltar in single-column tube stills, whereas the phenanthrene-carbazole fractions are a by-product in the production of high-grade anthracene by the acetone process. Coke-oven plants in other countries do not recover the fluoranthene fraction from coaltar. There are known methods of recovering technical fluoranthene from the II-nd anthracene fraction or pitch distillates. The pyrene fraction is recovered from heavy pitch distillates containing up to 8% pyrene, or from a mixture of these distillates and pitch tar. The chrysene fraction, containing 9.8% chrysene, can be recovered from the pyrene fraction first taken from pitch distillates. However, there is no published information on the yields and qualities of the various high-boiling fractions obtainable from different feedstocks, and what few data there are relate to the 1960s-1970s. The purpose of this work was to recover narrow high-boiling cuts from the >290 {degrees}centigrade residue which was recovered from a coal tar distillate. 6 refs., 3 tabs.

  20. 27 CFR 1.80 - Sales of distilled spirits in bulk.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ADMINISTRATION ACT, NONINDUSTRIAL USE OF DISTILLED SPIRITS AND WINE, BULK SALES AND BOTTLING OF DISTILLED SPIRITS Bulk Sales and Bottling of Distilled Spirits Bulk Sales and Bottling § 1.80 Sales of distilled...

  1. Ethyl carbamate in cachaça (Brazilian sugarcane spirit): Extended survey confirms simple mitigation approaches in pot still distillation.

    PubMed

    Nóbrega, Ian C C; Pereira, José A P; Paiva, José E; Lachenmeier, Dirk W

    2011-08-01

    In 2009, we reported an association between low levels of ethyl carbamate (EC) in pot still cachaças from Paraíba State, Brazil, and distillation in copper pot stills equipped with cooled columns. To strengthen these observations, we extended our study to Pernambuco State and assessed 13 pot still and 20 column still cachaça brands. An EC range from <40 to 532μg/l was found; 18 brands exceeded the Brazilian limit (150μg/l), 89% of which were column still types. Mean EC concentration of pot still cachaças was very low (64μg/l), and was well below the Paraíba study (220μg/l). An on-site investigation of pot still distilleries associated with <40μg/l brands showed a connection to differences in the distillation apparatus. Maximising distillation reflux ratios in the ascending parts and minimising exposure to copper in the descending parts (through the use of stainless steel) can reduce EC, and also avoid copper contamination. PMID:25214121

  2. 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.

  3. Slurry bubble column hydrodynamics

    NASA Astrophysics Data System (ADS)

    Rados, Novica

    Slurry bubble column reactors are presently used for a wide range of reactions in both chemical and biochemical industry. The successful design and scale up of slurry bubble column reactors require a complete understanding of multiphase fluid dynamics, i.e. phase mixing, heat and mass transport characteristics. The primary objective of this thesis is to improve presently limited understanding of the gas-liquid-solid slurry bubble column hydrodynamics. The effect of superficial gas velocity (8 to 45 cm/s), pressure (0.1 to 1.0 MPa) and solids loading (20 and 35 wt.%) on the time-averaged solids velocity and turbulent parameter profiles has been studied using Computer Automated Radioactive Particle Tracking (CARPT). To accomplish this, CARPT technique has been significantly improved for the measurements in highly attenuating systems, such as high pressure, high solids loading stainless steel slurry bubble column. At a similar set of operational conditions time-averaged gas and solids holdup profiles have been evaluated using the developed Computed Tomography (CT)/Overall gas holdup procedure. This procedure is based on the combination of the CT scans and the overall gas holdup measurements. The procedure assumes constant solids loading in the radial direction and axially invariant cross-sectionally averaged gas holdup. The obtained experimental holdup, velocity and turbulent parameters data are correlated and compared with the existing low superficial gas velocities and atmospheric pressure CARPT/CT gas-liquid and gas-liquid-solid slurry data. The obtained solids axial velocity radial profiles are compared with the predictions of the one dimensional (1-D) liquid/slurry recirculation phenomenological model. The obtained solids loading axial profiles are compared with the predictions of the Sedimentation and Dispersion Model (SDM). The overall gas holdup values, gas holdup radial profiles, solids loading axial profiles, solids axial velocity radial profiles and solids shear stress radial profiles are correlated using several widely used empirical correlations that are modified and improved to better represent present data.

  4. Temperature polarization coefficients in membrane distillation

    SciTech Connect

    Martinez-Diez, L.; Vazquez-Gonzalez, M.I.; Florido-Diaz, F.J.

    1998-04-01

    Membrane distillation is a membrane process in which two liquid phases at different temperatures are separated by a microporous hydrophobic membrane. The membrane plays the role of a physical support for the vapor-liquid interface. The aim of this paper is to study pure water transport by membrane distillation through a PTFE flat membrane. The dependence of the phenomenon on average temperature and recirculation rate at the membrane sides is investigated. The influence of these operating conditions on water transport is discussed by taking into account mass and heat transfer within the membrane and the adjoining liquid phases. The concept of temperature polarization is introduced into the transport equations and shown to be important in the interpretation of the experimental results.

  5. Nonlocal distillation based on multisetting Bell inequality

    NASA Astrophysics Data System (ADS)

    Ye, Xiang-Jun; Deng, Dong-Ling; Chen, Jing-Ling

    2012-12-01

    Inspired by the recent works of Foster [Phys. Rev. Lett.0031-900710.1103/PhysRevLett.102.120401 102, 120401 (2009)] and Brunner [Phys. Rev. Lett.0031-900710.1103/PhysRevLett.102.160403 102, 160403 (2009)], we present a nonlocality distillation protocol for two three-level (qutrit) systems in the framework of generalized nonsignaling theories. Our protocol is based on a three-setting Bell inequality. It works efficiently for a specific class of three-input-three-output nonlocal boxes. In the asymptotic limit, all these nonlocal boxes can be distilled to the maximally nonlocal box defined by the inequality and nonsignaling constraints. Then we introduce a contracting protocol that reduces these boxes to the so-called “correlated nonlocal boxes.” As a result, our three-input-three-output nonlocal boxes also make communication complexity trivial and appear very unlikely to exist in nature.

  6. Entanglement distillation in circuit quantum electrodynamics

    NASA Astrophysics Data System (ADS)

    Oppliger, Markus; Heinsoo, Johannes; Salathe, Yves; Potocnik, Anton; Mondal, Mintu; Wallraff, Andreas; Paraoanu, Gheorghe Sorin

    Entanglement is an essential resource for quantum information processing, such as quantum error correction, quantum teleportation and quantum communication. Such algorithms perform optimally with maximally entangled states. In practice entangled quantum states are very fragile due to a wide range of decoherence mechanisms. When two parties share degraded entangled states they are still able to generate an entangled state with higher fidelity using local operations and classical communication. This process is commonly referred to as entanglement distillation. Here we demonstrate distillation of highly entangled Bell states from two copies of less entangled states on a four transmon qubit device realized in the circuit-QED architecture. We characterize the output state for different degrees of entanglement at the input with quantum state tomography. A clear improvement of the entanglement measures is observed at the output.

  7. 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 μGC 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 100μm×100μm has been developed using silicon microfabrication techniques. The microfabricated column was benchmarked against a 2m 100μm 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 μGC column in temperature programmed mode. The demonstrated μGC column along with the high temperature fixture offers one more solution toward potentially realizing a portable μGC device for the detection of semi-volatile environmental pollutants and explosives without the thermal limitations reported to date with μGC columns using epoxy based interconnect technology. PMID:24866564

  8. Preparing titania aerogel monolithic chromatography columns using supercritical carbon dioxide.

    PubMed

    Sui, Ruohong; Liu, Suya; Lajoie, Gilles A; Charpentier, Paul A

    2010-06-01

    The search for a method to fabricate monolithic inorganic columns has attracted significant recent attention due to their unique ability in separation applications of various biomolecules. Silica and polymer based monolithic columns have been prepared, but titania and other metal oxide monoliths have been elusive, primarily due to their fragility. This article describes a new approach for preparing nanostructured titania based columns, which offer better performance over conventional particle packed columns for separating a wide variety of biomolecules including phosphopeptides. TiO(2) monolithic aerogels were synthesized in separation columns using in situ sol-gel reactions in supercritical carbon dioxide (scCO(2)) followed by calcination, and compared to those prepared in heptanes. The characterization results show that scCO(2) is a better solvent for the sol-gel reactions, providing lower shrinkage with the anatase TiO(2) monolith composed of nanofibers with very high surface areas. The monolithic columns show the ability to isolate phosphopeptides with little flow resistance compared to conventional titania particle based microcolumns. PMID:20373296

  9. Microfluidic distillation chip for methanol concentration detection.

    PubMed

    Wang, Yao-Nan; Liu, Chan-Chiung; Yang, Ruey-Jen; Ju, Wei-Jhong; Fu, Lung-Ming

    2016-03-17

    An integrated microfluidic distillation system is proposed for separating a mixed ethanol-methanol-water solution into its constituent components. The microfluidic chip is fabricated using a CO2 laser system and comprises a serpentine channel, a boiling zone, a heating zone, and a cooled collection chamber filled with de-ionized (DI) water. In the proposed device, the ethanol-methanol-water solution is injected into the microfluidic chip and driven through the serpentine channel and into the collection chamber by means of a nitrogen carrier gas. Following the distillation process, the ethanol-methanol vapor flows into the collection chamber and condenses into the DI water. The resulting solution is removed from the collection tank and reacted with a mixed indicator. Finally, the methanol concentration is inversely derived from the absorbance measurements obtained using a spectrophotometer. The experimental results show the proposed microfluidic system achieves an average methanol distillation efficiency of 97%. The practicality of the proposed device is demonstrated by detecting the methanol concentrations of two commercial fruit wines. It is shown that the measured concentration values deviate by no more than 3% from those obtained using a conventional bench top system. PMID:26920777

  10. Distillation Designs for the Lunar Surface

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

    Gravity-based distillation methods may be applied to the purification of wastewater on the lunar base. These solutions to water processing are robust physical separation techniques, which may be more advantageous than many other techniques for their simplicity in design and operation. The two techniques can be used in conjunction with each other to obtain high purity water. The components and feed compositions for modeling waste water streams are presented in conjunction with the Aspen property system for traditional stage distillation. While the individual components for each of the waste streams will vary naturally within certain bounds, an analog model for waste water processing is suggested based on typical concentration ranges for these components. Target purity levels for recycled water are determined for each individual component based on NASA s required maximum contaminant levels for potable water Optimum parameters such as reflux ratio, feed stage location, and processing rates are determined with respect to the power consumption of the process. Multistage distillation is evaluated for components in wastewater to determine the minimum number of stages necessary for each of 65 components in humidity condensate and urine wastewater mixed streams.

  11. Attractor mechanism as a distillation procedure

    SciTech Connect

    Levay, Peter; Szalay, Szilard

    2010-07-15

    In a recent paper it was shown that for double extremal static spherical symmetric BPS black hole solutions in the STU model the well-known process of moduli stabilization at the horizon can be recast in a form of a distillation procedure of a three-qubit entangled state of a Greenberger-Horne-Zeilinger type. By studying the full flow in moduli space in this paper we investigate this distillation procedure in more detail. We introduce a three-qubit state with amplitudes depending on the conserved charges, the warp factor, and the moduli. We show that for the recently discovered non-BPS solutions it is possible to see how the distillation procedure unfolds itself as we approach the horizon. For the non-BPS seed solutions at the asymptotically Minkowski region we are starting with a three-qubit state having seven nonequal nonvanishing amplitudes and finally at the horizon we get a Greenberger-Horne-Zeilinger state with merely four nonvanishing ones with equal magnitudes. The magnitude of the surviving nonvanishing amplitudes is proportional to the macroscopic black hole entropy. A systematic study of such attractor states shows that their properties reflect the structure of the fake superpotential. We also demonstrate that when starting with the very special values for the moduli corresponding to flat directions the uniform structure at the horizon deteriorates due to errors generalizing the usual bit flips acting on the qubits of the attractor states.

  12. The distillation and volatility of ionic liquids

    NASA Astrophysics Data System (ADS)

    Earle, Martyn J.; Esperança, José M. S. S.; Gilea, Manuela A.; Canongia Lopes, José N.; Rebelo, Luís P. N.; Magee, Joseph W.; Seddon, Kenneth R.; Widegren, Jason A.

    2006-02-01

    It is widely believed that a defining characteristic of ionic liquids (or low-temperature molten salts) is that they exert no measurable vapour pressure, and hence cannot be distilled. Here we demonstrate that this is unfounded, and that many ionic liquids can be distilled at low pressure without decomposition. Ionic liquids represent matter solely composed of ions, and so are perceived as non-volatile substances. During the last decade, interest in the field of ionic liquids has burgeoned, producing a wealth of intellectual and technological challenges and opportunities for the production of new chemical and extractive processes, fuel cells and batteries, and new composite materials. Much of this potential is underpinned by their presumed involatility. This characteristic, however, can severely restrict the attainability of high purity levels for ionic liquids (when they contain poorly volatile components) in recycling schemes, as well as excluding their use in gas-phase processes. We anticipate that our demonstration that some selected families of commonly used aprotic ionic liquids can be distilled at 200-300°C and low pressure, with concomitant recovery of significant amounts of pure substance, will permit these currently excluded applications to be realized.

  13. If You Were a Molecule in a Chromatography Column, What Would You See?

    NASA Astrophysics Data System (ADS)

    Mattice, John

    2008-07-01

    To visualize what takes place in a chromatography column, enlarge the molecules to human size and expand the columns to keep the ratio of size of molecule to size of column the same. If we were molecules, what would the columns be like? A typical gas chromatography (GC) capillary column would be 50 x 10 6 km (31 million mi) long, have a diameter of 420 km (260 mi), and have a stationary phase thickness of 420 m (a quarter of a mile). A typical high performance liquid chromatography (HPLC) column would be 3300 km (2000 mi) wide and longer than the distance from the earth to the moon. It would be packed with particles the size of Mt. Everest with a bonded stationary phase a little less than 4 m (12 to 13 ft) deep. Using this system, we explain how band broadening occurs as a result of resistance to mass transfer, multiple flow paths, and stagnant mobile phase.

  14. Experiments on Random Packings of Ellipsoids

    NASA Astrophysics Data System (ADS)

    Man, Weining; Donev, Aleksandar; Stillinger, Frank H.; Sullivan, Matthew T.; Russel, William B.; Heeger, David; Inati, Souheil; Torquato, Salvatore; Chaikin, P. M.

    2005-05-01

    Recent simulations indicate that ellipsoids can pack randomly more densely than spheres and, remarkably, for axes ratios near 1.25∶1∶0.8 can approach the densest crystal packing (fcc) of spheres, with a packing fraction of 74%. We demonstrate that such dense packings are realizable. We introduce a novel way of determining packing density for a finite sample that minimizes surface effects. We have fabricated ellipsoids and show that, in a sphere, the radial packing fraction ϕ(r) can be obtained from V(h), the volume of added fluid to fill the sphere to height h. We also obtain ϕ(r) from a magnetic resonance imaging scan. The measurements of the overall density ϕavr, ϕ(r) and the core density ϕ0=0.74±0.005 agree with simulations.

  15. The Packing of Granular Polymer Chains

    SciTech Connect

    Zou, Ling-Nan; Cheng, Xiang; Rivers, Mark L.; Jaeger, Heinrich M.; Nagel, Sidney R.; UC

    2009-12-01

    Rigid particles pack into structures, such as sand dunes on the beach, whose overall stability is determined by the average number of contacts between particles. However, when packing spatially extended objects with flexible shapes, additional concepts must be invoked to understand the stability of the resulting structure. Here, we examine the disordered packing of chains constructed out of flexibly connected hard spheres. Using x-ray tomography, we find that long chains pack into a low-density structure whose mechanical rigidity is mainly provided by the backbone. On compaction, randomly oriented, semi-rigid loops form along the chain, and the packing of chains can be understood as the jamming of these elements. Finally, we uncover close similarities between the packing of chains and the glass transition in polymers.

  16. Production of gasoline and distillate fuels from light cycle oil

    SciTech Connect

    Derr, W.R. Jr.; Owens, P.J.; Sarli, M.S.

    1991-01-15

    This patent describes a process for the co-production of high quality gasoline and distillate products from catalytically cracked feedstocks. It comprises: hydrocracking a substantially dealkylated feedstock with a hydrocracking catalyst at a hydrogen partial pressure not greater than 1200 psig and a conversion to gasoline boiling range products not more than 75 wt. percent; separating the products of hydrocracking into a gasoline boiling range fraction, a first distillate range fraction boiling immediately above the gasoline fraction with an end point in the range of 450{degrees} to 500{degrees} F. and a second distillate fraction boiling above the first distillate fraction; recycling at least a portion of the first distillate fraction to the hydrocracking step to effect saturation and partial cracking of aromatics in the recycled fraction to increase the paraffin content of the second distillate fraction; recovering the second distillate fraction.

  17. Qutrit Magic State Distillation Tight in Some Directions

    NASA Astrophysics Data System (ADS)

    Dawkins, Hillary; Howard, Mark

    2015-07-01

    Magic state distillation is a crucial component in the leading approaches to implementing universal fault-tolerant quantum computation, with existing protocols for both qubit and higher dimensional systems. Early work focused on determining the region of distillable states for qubit protocols; yet comparatively little is known about which states can be distilled and with what distillable region for d >2 . Here we focus on d =3 and present new four-qutrit distillation schemes that improve upon the known distillable region, and achieve distillation tight to the boundary of undistillable states for some classes of state. As a consequence of recent results, this implies that there is a family of quantum states that enable universality if and only if they exhibit contextuality with respect to stabilizer measurements. We also identify a new routine whose fixed point is a magic state with maximal sum negativity; i.e., it is maximally nonstablizer in a specific sense.

  18. Qutrit Magic State Distillation Tight in Some Directions.

    PubMed

    Dawkins, Hillary; Howard, Mark

    2015-07-17

    Magic state distillation is a crucial component in the leading approaches to implementing universal fault-tolerant quantum computation, with existing protocols for both qubit and higher dimensional systems. Early work focused on determining the region of distillable states for qubit protocols; yet comparatively little is known about which states can be distilled and with what distillable region for d>2. Here we focus on d=3 and present new four-qutrit distillation schemes that improve upon the known distillable region, and achieve distillation tight to the boundary of undistillable states for some classes of state. As a consequence of recent results, this implies that there is a family of quantum states that enable universality if and only if they exhibit contextuality with respect to stabilizer measurements. We also identify a new routine whose fixed point is a magic state with maximal sum negativity; i.e., it is maximally nonstablizer in a specific sense. PMID:26230774

  19. Secret key distillation from shielded two-qubit states

    SciTech Connect

    Bae, Joonwoo

    2010-05-15

    The quantum states corresponding to a secret key are characterized using the so-called private states, where the key part consisting of a secret key is shielded by the additional systems. Based on the construction, it was shown that a secret key can be distilled from bound entangled states. In this work, I consider the shielded two-qubit states in a key-distillation scenario and derive the conditions under which a secret key can be distilled using the recurrence protocol or the two-way classical distillation, advantage distillation together with one-way postprocessing. From the security conditions, it is shown that a secret key can be distilled from bound entangled states in a much wider range. In addition, I consider the case that in which white noise is added to quantum states and show that the classical distillation protocol still works despite a certain amount of noise although the recurrence protocol does not.

  20. Substituted Septithiophenes with End Groups of Different Size: Packing and Frustration in Bulk and Thin Films.

    PubMed

    de Jeu, Wim H; Rahimi, Khosrow; Ziener, Ulrich; Vill, Roman; Herzig, Eva M; Müller-Buschbaum, Peter; Möller, Martin; Mourran, Ahmed

    2016-02-16

    We report on three different liquid crystalline compounds with a central septithiophene core and alkylated end groups of strongly increasing bulkiness. In principle, the thiophene cores prefer to pack parallel to optimize their π-π interactions, which becomes sterically impossible for the bulkier end groups. Using X-ray diffraction, we find that the way out of this packing dilemma is toward liquid-crystal phases of higher dimensionality in the order smectic → columnar ↔ bicontinuous cubic. For the smectic phase, packing in a monolayer is no problem; for the other ones packing considerations become more stringent in films due to the boundaries. Surface X-ray techniques and atomic force microscopy indicate an appreciable difference between monolayer and three-layer films, in which the monolayers appear to escape from packing frustration by generating superstructures. We propose a basic structure of columns parallel to the substrate that provides a compromise between preserving some π-π interactions and packing the bulky alkyl groups. PMID:26807677

  1. Evaluation of 5 µm Superficially Porous Particles for Capillary and Microfluidic LC Columns

    PubMed Central

    Grinias, James P.; Kennedy, Robert T.

    2015-01-01

    Large-size (4–5 µm) superficially porous particles yield lower plate heights (e.g., the minimal reduced plate height or hmin ≈ 1.5) than fully porous particles of a similar size when packed into large-bore columns. This property allows for better chromatographic performance without the higher pressures required for smaller particles. This study explores the use of such particles in microfluidic LC columns where materials and fitting pressure limits can constrain the size of particle used. The theoretically predicted performance improvements compared to fully porous particles were not demonstrated in capillary columns (with hmin ≈ 2 for both particle types), in agreement with previous studies that examined smaller superficially porous particles. Microfluidic columns were then compared to capillary columns. Capillary columns significantly outperformed microfluidic columns due to imperfections imposed by microfluidic channel asymmetry and world-to-chip connection at the optimal flow rate; however, superficially porous particles packed in microfluidic LC columns had flatter plate height versus flow rate curves indicating potential for better performance at high reduced velocities. PMID:26714261

  2. Toxicity of middle distillates from dermal exposure.

    PubMed

    Koschier, F J

    1999-02-01

    This report focuses on recent studies that investigated the effects of kerosine dermal exposure on neurotoxicity and reproductive/developmental toxicity. Background toxicity information will also be reviewed for kerosine range mid distillates. The kerosine range mid distillates have a carbon range of C9-C16 and have a boiling range of 302-554 degrees F (150-290 degrees C). This category includes kerosine, aviation fuels (e.g., Jet A, JP-5 and JP-8), no. 1 fuel oil and diesel fuel oil. In general, the kerosine range mid distillates demonstrate relatively low acute toxicity by any route of exposure. High inhalation exposures can induce central nervous system depression characterized by ataxia, hypoactivity and prostration. Kerosines are known to cause skin irritation and inflammation under conditions of acute and repeated exposure in animals and humans, but are only slightly irritating to the eye and are not skin sensitizers. In addition, the absorption of kerosine range mid distillates through the skin has been demonstrated to be fairly rapid, but limited to approximately 10-15% of the applied dose after 24 hours. The kerosine range mid distillates are generally inactive in genetic toxicity tests although positive studies have been reported. Positive results, while at times equivocal, have been reported for straight run kerosine and jet fuel A in the mouse lymphoma assay with metabolic activation, and hydrodesulfurized kerosine (mouse) and jet fuel A (rat) in the bone marrow cytogenetic assay. Effects on the nervous and reproductive systems have been reported in humans and experimental animals under conditions where inhalation and dermal exposure to specific kerosine type fuels are sometimes difficult to separate. Recent laboratory studies have addressed this point and examined the effects of dermal exposure. In these studies, rats were exposed to hydrodesulfurized kerosine by skin application to determine the potential of dermal contact to cause reproductive/developmental toxicity (OECD Guideline 421) or neurotoxicity (TSCA Guidelines on subchronic inhalation and neurotoxicity studies). These studies demonstrated that the highest dose level of kerosine does not induce reproductive/developmental or neurotoxicity effects by skin exposure in rodent studies. The dermal NOEL for HDS kerosine in rats was > or = 494 mg/kg for both neurotoxicity, and reproductive/developmental toxicity. PMID:10189576

  3. [Removal of Mixed Waste Gases by a Biotrickling Filter Packed with a Novel Combined Packing Material].

    PubMed

    Mei, Yu; Cheng, Zhuo-wei; Wang, Jia-de; Lu, Yin

    2015-12-01

    A pilot biotrickling filter (BTF) was set up for removal of a mixed waste gas containing toluene and ethanol. The packing material was composed of polyhedral sphere and polyhedral hollow column previously designed by our group. The results showed this BTF could successfully start up within only 8 d and the average eliminate capacities for toluene and ethanol were 97.14 and 113.10 g · (m³ · h)⁻¹, respectively. Empty bed residence time (EBRT) and the inlet concentration had effects on the removal of toluene. The maximum elimination capacity of toluene and ethanol was 123.34 and 206.36 g (m³ · h)⁻¹ under EBRT of 21.11 s, respectively. However, the effect of spray liquid density was not obvious, and the optimal value of solution and gas ratio was 6.82 L · m⁻³. The influence of unstable processing condition on its performance was also investigated. NaOH solution could effectively reduce the plugging of the filler layer, and the removal capability of pollutant could be recovered within 3 days. After the running was stopped for 10 d, the removal performance of this BTF could be quickly recovered. PMID:27011972

  4. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON... according to size, internal quality, and external appearance and condition of hazelnuts packed in...

  5. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON... according to size, internal quality, and external appearance and condition of hazelnuts packed in...

  6. Random packing of spheres in Menger sponge

    NASA Astrophysics Data System (ADS)

    Cieśla, Michał; 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.

  7. Random packing of spheres in Menger sponge.

    PubMed

    Cieśla, Michał; 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. PMID:23758392

  8. 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 pH and ionic strength. Other methods are used to test how pesticides may interact with soil components to change mobility. Spectroscopic approaches are used to analyze the nature of soil pesticide complexes. These may provide insight into the mechanism by which interactions occur. Other studies may be performed to determine the effect of agricultural practices (e.g., tillage) on pesticide leaching under controlled conditions using intact soil cores from the field. When preferential flow is suspected to occur, dye staining is used to examine the contribution of macropores to pesticide transport. These methods and others are addressed in the text of this review. PMID:23090630

  9. Minimally packed phases in holography

    NASA Astrophysics Data System (ADS)

    Donos, Aristomenis; Gauntlett, Jerome P.

    2016-03-01

    We numerically construct asymptotically AdS black brane solutions of D = 4 Einstein-Maxwell theory coupled to a pseudoscalar. The solutions are holographically dual to d = 3 CFTs at finite chemical potential and in a constant magnetic field, which spontaneously break translation invariance leading to the spontaneous formation of abelian and momentum magnetisation currents flowing around the plaquettes of a periodic Bravais lattice. We analyse the three-dimensional moduli space of lattice solutions, which are generically oblique, and show, for a specific value of the magnetic field, that the free energy is minimised by the triangular lattice, associated with minimal packing of circles in the plane. We show that the average stress tensor for the thermodynamically preferred phase is that of a perfect fluid and that this result applies more generally to spontaneously generated periodic phases. The triangular structure persists at low temperatures indicating the existence of novel crystalline ground states.

  10. Chain packing in polycarbonate glasses.

    PubMed

    Stueber, Dirk; Yu, Tsyr-Yan; Hess, Berk; Kremer, Kurt; O'Connor, Robert D; Schaefer, Jacob

    2010-03-14

    Chain packing in homogeneous blends of carbonate (13)C-labeled bisphenol A polycarbonate with either (i) CF(3)-labeled bisphenol A polycarbonate or (ii) ring-F-labeled bisphenol A polycarbonate has been characterized using (13)C{(19)F} rotational-echo double-resonance (REDOR) nuclear magnetic resonance. In both blends, the (13)C observed spin was at high concentration, and the (19)F dephasing or probe spin was at low concentration. In this situation, an analysis in terms of a distribution of isolated heteronuclear pairs of spins is valid. Nearest-neighbor separation of (13)C and (19)F labels was determined by accurately mapping the initial dipolar evolution using a shifted-pulse version of REDOR. Based on the results of this experiment, the average distance from a ring-fluorine to the nearest (13)C=O is more than 1.2 A greater than the corresponding CF(3)-(13)C=O distance. Next-nearest and more-distant-neighbor separations of labels were measured in a 416-rotor-cycle constant-time version of REDOR for both blends. Statistically significant local order was established for the nearest-neighbor labels in the methyl-labeled blend. These interchain packing results are in qualitative agreement with predictions based on coarse-grained simulations of a specially adapted model for bisphenol A polycarbonate. The model itself has been previously used to determine static and dynamic properties of polycarbonate with results in good agreement with those from rheological and neutron scattering experiments. PMID:20232984

  11. Chain packing in polycarbonate glasses

    NASA Astrophysics Data System (ADS)

    Stueber, Dirk; Yu, Tsyr-Yan; Hess, Berk; Kremer, Kurt; O'Connor, Robert D.; Schaefer, Jacob

    2010-03-01

    Chain packing in homogeneous blends of carbonate C13-labeled bisphenol A polycarbonate with either (i) CF3-labeled bisphenol A polycarbonate or (ii) ring-F-labeled bisphenol A polycarbonate has been characterized using C13{F19} rotational-echo double-resonance (REDOR) nuclear magnetic resonance. In both blends, the C13 observed spin was at high concentration, and the F19 dephasing or probe spin was at low concentration. In this situation, an analysis in terms of a distribution of isolated heteronuclear pairs of spins is valid. Nearest-neighbor separation of C13 and F19 labels was determined by accurately mapping the initial dipolar evolution using a shifted-pulse version of REDOR. Based on the results of this experiment, the average distance from a ring-fluorine to the nearest C13O is more than 1.2 Å greater than the corresponding CF3C13O distance. Next-nearest and more-distant-neighbor separations of labels were measured in a 416-rotor-cycle constant-time version of REDOR for both blends. Statistically significant local order was established for the nearest-neighbor labels in the methyl-labeled blend. These interchain packing results are in qualitative agreement with predictions based on coarse-grained simulations of a specially adapted model for bisphenol A polycarbonate. The model itself has been previously used to determine static and dynamic properties of polycarbonate with results in good agreement with those from rheological and neutron scattering experiments.

  12. ARK-o-hol community experiment group: a cooperatively operated greenhouse heated with low-grade waste heat from an adjacent alcohol distillation plant. Final report

    SciTech Connect

    Not Available

    1983-01-01

    In order to prove that low-grade waste heat (from an alcohol distillation plant, in this case) could successfully be transported and recycled, a 28' x 60' greenhouse was designed and constructed adjacent to and connected by plumbing with an operating alcohol distillation plant. Hot water in the return lines of heat exchangers in the distillation column of the alcohol plant was emptied into a 20' x 20' in ground heat storage tank within the greenhouse. This heated water was then circulated throughout the greenhouse by means of 7' x 10' floor plates (surplus reefer heat exchangers). The heat-storage tank, drawing its heat from the distillation column waste-heat, in addition to daytime solar gain, maintained a temperature of 62 to 65 degrees by day, dropping to 60 degrees at night, provided the greenhouse with an average of 60,000 Btu's per hour of nighttime usable heat. The greenhouse was operated throughout the winter 1982/1983 which had unpredictable temperatures climbing to 85 degrees, followed immediately by a week of 18 degrees. In April 1983, 18,500 tomato plants and more than 5000 other vegetables and house plants, were ready for harvest, although no supplemental heater was used, the only heat being distillation plant waste heat and daytime solar gain.

  13. Confined disordered strictly jammed binary sphere packings

    NASA Astrophysics Data System (ADS)

    Chen, D.; Torquato, S.

    2015-12-01

    Disordered jammed packings under confinement have received considerably less attention than their bulk counterparts and yet arise in a variety of practical situations. In this work, we study binary sphere packings that are confined between two parallel hard planes and generalize the Torquato-Jiao (TJ) sequential linear programming algorithm [Phys. Rev. E 82, 061302 (2010), 10.1103/PhysRevE.82.061302] to obtain putative maximally random jammed (MRJ) packings that are exactly isostatic with high fidelity over a large range of plane separation distances H , small to large sphere radius ratio α , and small sphere relative concentration x . We find that packing characteristics can be substantially different from their bulk analogs, which is due to what we term "confinement frustration." Rattlers in confined packings are generally more prevalent than those in their bulk counterparts. We observe that packing fraction, rattler fraction, and degree of disorder of MRJ packings generally increase with H , though exceptions exist. Discontinuities in the packing characteristics as H varies in the vicinity of certain values of H are due to associated discontinuous transitions between different jammed states. When the plane separation distance is on the order of two large-sphere diameters or less, the packings exhibit salient two-dimensional features; when the plane separation distance exceeds about 30 large-sphere diameters, the packings approach three-dimensional bulk packings. As the size contrast increases (as α decreases), the rattler fraction dramatically increases due to what we call "size-disparity" frustration. We find that at intermediate α and when x is about 0.5 (50-50 mixture), the disorder of packings is maximized, as measured by an order metric ψ that is based on the number density fluctuations in the direction perpendicular to the hard walls. We also apply the local volume-fraction variance στ2(R ) to characterize confined packings and find that these packings possess essentially the same level of hyperuniformity as their bulk counterparts. Our findings are generally relevant to confined packings that arise in biology (e.g., structural color in birds and insects) and may have implications for the creation of high-density powders and improved battery designs.

  14. Determination of 5-nitroimidazole residues in milk by capillary electrochromatography with packed C18 silica beds.

    PubMed

    Hernández-Mesa, Maykel; Lara, Francisco J; Cruces-Blanco, Carmen; García-Campaña, Ana M

    2015-11-01

    This work presents a novel methodology for analysing 5-nitroimidazole residues in milk samples by capillary electrochromatography using lab-made packed columns, produced by carrying out a high pressure packing procedure using acetone as driving solvent and C18 silica uncapped particles (5 µm particle size) as packing material. Column frits resulted from sintering the proper stationary phase by heating the packed material for 20s with a nichrome ribbon (80% Ni-20% Cr, 28 cm × 2 mm × 0.2 mm, electric resistance 1.3 Ω) connected to a 7 V AC power supply. Lab-made C18 silica packed capillaries (40 cm x 50 µm i.d.) were employed for the determination of 5-nitroimidazole drugs. Milk samples were treated by a salting-out assisted liquid-liquid extraction followed by a solid phase extraction with Oasis®HLB cartridges prior to their injection. Samples were hydrodynamically injected into the column for 120 s at 11.5 bar. Afterwards eight 5-nitroimidazole compounds were separated in isocratic mode under an applied voltage of 27 kV and a temperature of 30 °C. The selected mobile phase consisted of a mixture 60:40 acetonitrile:ammonium acetate (2.5 mM, pH=5). Separation was monitored at 320 nm and it was performed in less than 15 min. The method was characterized in terms of linearity (R(2)≥0.993) and precision (repeatability, RSD≤12.2% and reproducibility, RSD≤14.5%), obtaining detection limits lower than 29 µg/L for all compounds under study. PMID:26452860

  15. 49 CFR 173.133 - Assignment of packing group and hazard zones for Division 6.1 materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... B stated in paragraph (a)(2) of this section is a material poisonous by inhalation subject to the... this paragraph, the packing group and hazard zone of a tear gas substance is as assigned in column 5 of... poisonous (toxic) by inhalation may be determined by one of the following methods: (1) Where LC50 data...

  16. 29 CFR 784.135 - Packing.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... FISHING AND OPERATIONS ON AQUATIC PRODUCTS Exemptions Provisions Relating to Fishing and Aquatic Products... packing of the various named marine products at sea as an incident to, or in conjunction with, the fishing..., sizing, and placing layers of crushed ice in the containers are deemed a part of packing when...

  17. 29 CFR 784.135 - Packing.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... FISHING AND OPERATIONS ON AQUATIC PRODUCTS Exemptions Provisions Relating to Fishing and Aquatic Products... packing of the various named marine products at sea as an incident to, or in conjunction with, the fishing..., sizing, and placing layers of crushed ice in the containers are deemed a part of packing when...

  18. 29 CFR 784.135 - Packing.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... FISHING AND OPERATIONS ON AQUATIC PRODUCTS Exemptions Provisions Relating to Fishing and Aquatic Products... packing of the various named marine products at sea as an incident to, or in conjunction with, the fishing..., sizing, and placing layers of crushed ice in the containers are deemed a part of packing when...

  19. Record high Wolf, Canis lupus, pack density

    USGS Publications Warehouse

    Mech, L.D.; Tracy, S.

    2004-01-01

    This report documents a year-around Wolf (Canis lupus) density of 18.2/100 km2 and a summer density of 30.8/100 km2, in a northeastern Minnesota Wolf pack. The previous record was a summer density of 14.1/100 km2, for a Wolf pack on Vancouver Island, British Columbia, Canada.

  20. Record high wolf, Canis lupus, pack density

    USGS Publications Warehouse

    Mech, L.D.; Tracy, S.

    2004-01-01

    This report documents a year-around wolf (Canis lupus) density of 18.2/100 m2 and summer density of 30.8/100 km2, in a northeastern Minnesota wolf pack. The previous record was a summer density of 14.1/100 km2, for a wolf pack on Vancouver Island, BC, Canada.