Science.gov

Sample records for air purification

  1. Air/Water Purification

    NASA Technical Reports Server (NTRS)

    1992-01-01

    After 18 years of research into air/water pollution at Stennis Space Center, Dr. B. C. Wolverton formed his own company, Wolverton Environmental Services, Inc., to provide technology and consultation in air and water treatment. Common houseplants are used to absorb potentially harmful materials from bathrooms and kitchens. The plants are fertilized, air is purified, and wastewater is converted to clean water. More than 100 U.S. communities have adopted Wolverton's earlier water hyacinth and artificial marsh applications. Catfish farmers are currently evaluating the artificial marsh technology as a purification system.

  2. Photocatalytic materials and technologies for air purification.

    PubMed

    Ren, Hangjuan; Koshy, Pramod; Chen, Wen-Fan; Qi, Shaohua; Sorrell, Charles Christopher

    2017-03-05

    Since there is increasing concern for the impact of air quality on human health, the present work surveys the materials and technologies for air purification using photocatalytic materials. The coverage includes (1) current photocatalytic materials for the decomposition of chemical contaminants and disinfection of pathogens present in air and (2) photocatalytic air purification systems that are used currently and under development. The present work focuses on five main themes. First, the mechanisms of photodegradation and photodisinfection are explained. Second, system designs for photocatalytic air purification are surveyed. Third, the photocatalytic materials used for air purification and their characteristics are considered, including both conventional and more recently developed photocatalysts. Fourth, the methods used to fabricate these materials are discussed. Fifth, the most significant coverage is devoted to materials design strategies aimed at improving the performance of photocatalysts for air purification. The review concludes with a brief consideration of promising future directions for materials research in photocatalysis.

  3. Breathing air purification; Desiccant vs. refrigerated

    SciTech Connect

    McKay, K.L.; Swanson, A.L. )

    1986-07-01

    Carbon monoxide (CO) is a common contaminant of ambient air - levels as high as 200 ppm are not uncommon in urban, industrial, or high automotive-traffic areas. Carbon monoxide may also be produced by the oxidation of lubricating oil in overheated compressors. Air from an oil-lubricated compressor, even when an aftercooler is used, often contains significant quantities of oil mist and vapor. Even where a breathing air (non-oil-lubricated) compressor is used , oil. levels in the air taken into the compressor can still exceed Grade D standards, especially in industrial environments. Other contaminants (gaseous hydrocarbons, particulate matter, and odors), while not addressed by the Grade D criteria, are also present in harmful or objectionable levels in industrial environments; therefore, they must be taken into account in the design of the air purification systems. This paper discusses two basic types of breathing air purifiers: desiccant and refrigerated purifiers.

  4. Microwave Regenerable Air Purification Device

    NASA Technical Reports Server (NTRS)

    Atwater, James E.; Holtsnider, John T.; Wheeler, Richard R., Jr.

    1996-01-01

    The feasibility of using microwave power to thermally regenerate sorbents loaded with water vapor, CO2, and organic contaminants has been rigorously demonstrated. Sorbents challenged with air containing 0.5% CO2, 300 ppm acetone, 50 ppm trichloroethylene, and saturated with water vapor have been regenerated, singly and in combination. Microwave transmission, reflection, and phase shift has also been determined for a variety of sorbents over the frequency range between 1.3-2.7 GHz. This innovative technology offers the potential for significant energy savings in comparison to current resistive heating methods because energy is absorbed directly by the material to be heated. Conductive, convective and radiative losses are minimized. Extremely rapid heating is also possible, i.e., 1400 C in less than 60 seconds. Microwave powered thermal desorption is directly applicable to the needs of Advance Life Support in general, and of EVA in particular. Additionally, the applicability of two specific commercial applications arising from this technology have been demonstrated: the recovery for re-use of acetone (and similar solvents) from industrial waste streams using a carbon based molecular sieve; and the separation and destruction of trichloroethylene using ZSM-5 synthetic zeolite catalyst, a predominant halocarbon environmental contaminant. Based upon these results, Phase II development is strongly recommended.

  5. 9. Water Purification System and Instrument Air Receiver Tank, view ...

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

    9. Water Purification System and Instrument Air Receiver Tank, view to the south. The water purification system is visible in the right foreground of the photograph and the instrument air receiver tank is visible in the right background of the photograph. - Washington Water Power Clark Fork River Cabinet Gorge Hydroelectric Development, Powerhouse, North Bank of Clark Fork River at Cabinet Gorge, Cabinet, Bonner County, ID

  6. A portable breathing air control and purification unit

    SciTech Connect

    Pickett, R.L. II )

    1983-10-01

    The use of an installed plant air system as a breathing air supply poses several problems, including the potential for contamination of the air, the chance for rapid loss of air without warning, inconvenient locations of outlet stations, and poor control over air quality, flow, and pressure. It is possible to solve these problems without requiring major modifications to the installed air system by examining the breathing air supply route as a whole and utilizing an add-on adaptor to convert the output of the plant air system into a reliable, pure, and convenient source of breathing air for respirator users. The breathing air control and purification unit described in this article functions as just such an adaptor by purifying plant service air, controlling the distribution of this purified air to up to four respirator users, monitoring for the presence of carbon monoxide, and providing respirator users, monitoring for the presence of carbon monoxide, and providing alarms and a reserve air supply to protect against a loss of service air pressure.

  7. NASA - Johnson Space Center's New Capabilities for Air Purification

    NASA Technical Reports Server (NTRS)

    Graf, John

    2015-01-01

    NASA has some unique and challenging air purification problems that cannot be adequately met with COTS technology: 1) ammonia removal from air, 2) hydrazine removal from air, 3) CO conversion to CO2 in low temperature, high humidity environments. NASA has sponsored the development of new sorbents and new catalysts. These new sorbents and catalysts work better than COTS technology for our application. If attendees have a need for an effective ammonia sorbent, an effective hydrazine sorbent, or an effective CO conversion catalyst, we should learn to see if NASA sponsored technology development can help.

  8. Photodetoxification and purification of water and air

    SciTech Connect

    Anderson, M.; Blake, D.M.

    1996-09-01

    The scope of interest in this section is basic research in photochemistry that can remove barriers to the development of photochemical technologies for the removal of hazardous chemicals from contaminated air or water (photodetoxification). Photochemistry is be broadly interpreted to include direct photochemistry, indirect photochemistry (sensitized and photocatalytic), photochemistry of species adsorbed on inert surfaces, and complementary effects of high energy radiation photons and particles. These may occur in either homogeneous or heterogeneous media. The photon source may span the range from ionizing radiation to the near infrared.

  9. Regenerable Air Purification System for Gas-Phase Contaminant Control

    NASA Technical Reports Server (NTRS)

    Constantinescu, Ileana C.; Finn, John E.; LeVan, M. Douglas; Lung, Bernadette (Technical Monitor)

    2000-01-01

    Tests of a pre-prototype regenerable air purification system (RAPS) that uses water vapor to displace adsorbed contaminants from an adsorbent column have been performed at NASA Ames Research Center. A unit based on this design can be used for removing trace gas-phase contaminants from spacecraft cabin air or from polluted process streams including incinerator exhaust. During the normal operation mode, contaminants are removed from the air on the column. Regeneration of the column is performed on-line. During regeneration, contaminants are displaced and destroyed inside the closed oxidation loop. In this presentation we discuss initial experimental results for the performance of RAPS in the removal and treatment of several important spacecraft contaminant species from air.

  10. Regenerable Air Purification System for Gas-Phase Contaminant Control

    NASA Technical Reports Server (NTRS)

    Constantinescu, Ileana C.; Finn, John E.; LeVan, M. Douglas; Lung, Bernadette (Technical Monitor)

    2000-01-01

    Tests of a pre-prototype regenerable air purification system (RAPS) that uses water vapor to displace adsorbed contaminants from an adsorbent column have been performed at NASA Ames Research Center. A unit based on this design can be used for removing trace gas-phase contaminants from spacecraft cabin air or from polluted process streams including incinerator exhaust. During the normal operation mode, contaminants are removed from the air on the column. Regeneration of the column is performed on-line. During regeneration, contaminants are displaced and destroyed inside the closed oxidation loop. In this presentation we discuss initial experimental results for the performance of RAPS in the removal and treatment of several important spacecraft contaminant species from air.

  11. New research on bioregenerative air/water purification systems

    NASA Technical Reports Server (NTRS)

    Johnson, Anne H.; Ellender, R. D.; Watkins, Paul J.

    1991-01-01

    For the past several years, air and water purification systems have been developed and used. This technology is based on the combined activities of plants and microorganisms as they function in a natural environment. More recently, researchers have begun to address the problems associated with indoor air pollution. Various common houseplants are currently being evaluated for their abilities to reduce concentrations of volatile organic compounds (VOCS) such as formaldehyde and benzene. With development of the Space Exploration Initiative, missions will increase in duration, and problems with resupply necessitates implementation of regenerative technology. Aspects of bioregenerative technology have been included in a habitat known as the BioHome. The ultimate goal is to use this technology in conjunction with physicochemical systems for air and water purification within closed systems. This study continued the risk assessment of bioregenerative technology with emphasis on biological hazards. In an effort to evaluate the risk for human infection, analyses were directed at enumeration of fecal streptococci and enteric viruses with the BioHome waste water treatment system.

  12. Regenerable Air Purification System for Gas-Phase Contaminant Control

    NASA Technical Reports Server (NTRS)

    Constantinescu, Ileana C.; Qi, Nan; LeVan, M. Douglas; Finn, Cory K.; Finn, John E.; Luna, Bernadette (Technical Monitor)

    2000-01-01

    A regenerable air purification system (RAPS) that uses water vapor to displace adsorbed contaminants from an. adsorbent column into a closed oxidation loop is under development through cooperative R&D between Vanderbilt University and NASA Ames Research Center. A unit based on this design can be used for removing trace gas-phase contaminants from spacecraft cabin air or from polluted process streams including incinerator exhaust. Recent work has focused on fabrication and operation of a RAPS breadboard at NASA Ames, and on measurement of adsorption isotherm data for several important organic compounds at Vanderbilt. These activities support the use and validation of RAPS modeling software also under development at Vanderbilt, which will in turn be used to construct a prototype system later in the project.

  13. Regenerable Air Purification System for Gas-Phase Contaminant Control

    NASA Technical Reports Server (NTRS)

    Constantinescu, Ileana C.; Qi, Nan; LeVan, M. Douglas; Finn, Cory K.; Finn, John E.; Luna, Bernadette (Technical Monitor)

    2000-01-01

    A regenerable air purification system (RAPS) that uses water vapor to displace adsorbed contaminants from an. adsorbent column into a closed oxidation loop is under development through cooperative R&D between Vanderbilt University and NASA Ames Research Center. A unit based on this design can be used for removing trace gas-phase contaminants from spacecraft cabin air or from polluted process streams including incinerator exhaust. Recent work has focused on fabrication and operation of a RAPS breadboard at NASA Ames, and on measurement of adsorption isotherm data for several important organic compounds at Vanderbilt. These activities support the use and validation of RAPS modeling software also under development at Vanderbilt, which will in turn be used to construct a prototype system later in the project.

  14. Air Purification in Closed Environments: An Overview of Spacecraft Systems

    NASA Technical Reports Server (NTRS)

    Perry, Jay L.; LeVan, Douglas; Crumbley, Robert (Technical Monitor)

    2002-01-01

    The primary goal for a collective protection system and a spacecraft environmental control and life support system (ECLSS) are strikingly similar. Essentially both function to provide the occupants of a building or vehicle with a safe, habitable environment. The collective protection system shields military and civilian personnel from short-term exposure to external threats presented by toxic agents and industrial chemicals while an ECLSS sustains astronauts for extended periods within the hostile environment of space. Both have air quality control similarities with various aircraft and 'tight' buildings. This paper reviews basic similarities between air purification system requirements for collective protection and an ECLSS that define surprisingly common technological challenges and solutions. Systems developed for air revitalization on board spacecraft are discussed along with some history on their early development as well as a view of future needs. Emphasis is placed upon two systems implemented by the National Aeronautics and Space Administration (NASA) onboard the International Space Station (ISS): the trace contaminant control system (TCCS) and the molecular sieve-based carbon dioxide removal assembly (CDRA). Over its history, the NASA has developed and implemented many life support systems for astronauts. As the duration, complexity, and crew size of manned missions increased from minutes or hours for a single astronaut during Project Mercury to days and ultimately months for crews of 3 or more during the Apollo, Skylab, Shuttle, and ISS programs, these systems have become more sophisticated. Systems aboard spacecraft such as the ISS have been designed to provide long-term environmental control and life support. Challenges facing the NASA's efforts include minimizing mass, volume, and power for such systems, while maximizing their safety, reliability, and performance. This paper will highlight similarities and differences among air purification systems

  15. Air Purification in Closed Environments: An Overview of Spacecraft Systems

    NASA Technical Reports Server (NTRS)

    Perry, Jay L.; LeVan, Douglas; Crumbley, Robert (Technical Monitor)

    2002-01-01

    The primary goal for a collective protection system and a spacecraft environmental control and life support system (ECLSS) are strikingly similar. Essentially both function to provide the occupants of a building or vehicle with a safe, habitable environment. The collective protection system shields military and civilian personnel from short-term exposure to external threats presented by toxic agents and industrial chemicals while an ECLSS sustains astronauts for extended periods within the hostile environment of space. Both have air quality control similarities with various aircraft and 'tight' buildings. This paper reviews basic similarities between air purification system requirements for collective protection and an ECLSS that define surprisingly common technological challenges and solutions. Systems developed for air revitalization on board spacecraft are discussed along with some history on their early development as well as a view of future needs. Emphasis is placed upon two systems implemented by the National Aeronautics and Space Administration (NASA) onboard the International Space Station (ISS): the trace contaminant control system (TCCS) and the molecular sieve-based carbon dioxide removal assembly (CDRA). Over its history, the NASA has developed and implemented many life support systems for astronauts. As the duration, complexity, and crew size of manned missions increased from minutes or hours for a single astronaut during Project Mercury to days and ultimately months for crews of 3 or more during the Apollo, Skylab, Shuttle, and ISS programs, these systems have become more sophisticated. Systems aboard spacecraft such as the ISS have been designed to provide long-term environmental control and life support. Challenges facing the NASA's efforts include minimizing mass, volume, and power for such systems, while maximizing their safety, reliability, and performance. This paper will highlight similarities and differences among air purification systems

  16. [The design of air purification system and its effect on surgical ICU].

    PubMed

    Su, L; Li, H; Bai, T

    1996-05-01

    It is very important to protect air-cross infection and improve air quality in surgical intensive care unit. In the design and effect of "local air condition and purification control system", air microbe colony counter was greatly reduced to 48/m3 (control area), and 105/m3 (uncontrol area), compared to 618/m3 (untreatment), P < 0.01. This system shows stable function, sterilization effect, low cost, and is useful to protect air pollution in surgical intensive care unit.

  17. Chemical Protection Testing of Sorbent-Based Air Purification Components (APCs)

    DTIC Science & Technology

    2016-06-24

    based on the nature of the BFC, its prevalence on the battlefield, and potential interactions with the filtration media. If possible, a single design...3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Test Operations Procedure (TOP) 08-2-197 Chemical Protection Testing of Sorbent- Based Air...Operations Procedure (TOP) provides preparation, planning, conducting, and reporting procedures for testing sorbent- based air purification components (APCs

  18. Air Purification Effect of Positively and Negatively Charged Ions Generated by Discharge Plasma at Atmospheric Pressure

    NASA Astrophysics Data System (ADS)

    Nishikawa, Kazuo; Nojima, Hideo

    2001-08-01

    In this paper, the air purification effect of positively and negatively charged ions generated by discharge plasma at atmospheric pressure is reported. We have developed a novel ion generation device which consists of a cylindrical glass tube and attached inner and outer mesh electrodes. With the application of AC voltage between the electrodes, positively charged ions and negatively charged ions have been generated at atmospheric pressure. The ion densities of 3.0× 104--7.0× 104 counts/cm3 have been obtained with the AC voltage of 1.8-2.3 kV (effective value). We have examined the air purification properties of this device. By the operation of this device, the initial oxygen nitride (NO) density of 10 ppm in 1 m3 (in cigarette smoke) was decreased to 1 ppm after 30 min. The number of suspended germs in air has been significantly reduced by the use of this type of ion generation device.

  19. Air purification in industrial plants producing automotive rubber components in terms of energy efficiency

    NASA Astrophysics Data System (ADS)

    Grzebielec, Andrzej; Rusowicz, Artur; Szelągowski, Adam

    2017-04-01

    In automotive industry plants, which use injection molding machines for rubber processing, tar contaminates air to such an extent that air fails to enter standard heat recovery systems. Accumulated tar clogs ventilation heat recovery exchangers in just a few days. In the plant in which the research was conducted, tar contamination causes blockage of ventilation ducts. The effect of this phenomenon was that every half year channels had to be replaced with new ones, since the economic analysis has shown that cleaning them is not cost-efficient. Air temperature inside such plants is often, even in winter, higher than 30°C. The air, without any means of heat recovery, is discharged outside the buildings. The analyzed plant uses three types of media for production: hot water, cold water at 14°C (produced in a water chiller), and compressed air, generated in a unit with a rated power consumption of 180 kW. The aim of the study is to determine the energy efficiency improvement of this type of manufacturing plant. The main problem to solve is to provide an air purification process so that air can be used in heat recovery devices. The next problem to solve is to recover heat at such a temperature level that it would be possible to produce cold for technological purposes without air purification. Experimental studies have shown that air purification is feasible. By using one microjet head, a total of 75% of tar particles was removed from the air; by using 4 heads, a purification efficiency of 93% was obtained. This method of air purification causes air temperature to decrease from 35°C to 20°C, which significantly reduces the potential for heat recovery. The next step of the research was designing a cassette-plate heat exchanger to exchange heat without air purification. The economic analysis of such a solution revealed that replacing the heat exchanger with a new one even once a year was not cost-efficient. Another issue examined in the context of energy efficiency was

  20. [Biocatalysis using immobilized cells or enzymes as a method of water and air purification in habitable enclosed environment].

    PubMed

    Lebedeva, T E; Nazarov, N M; Siniak, Iu E

    1991-01-01

    This paper shows that the method of water and air purification using immobilized cells and enzymes can be applied in regenerative life support systems in a habitable enclosed environment. This method is based on selective and adaptive functions of enzymic systems of microorganisms to assimilate organic components of the medium to be eliminated. Advantages of biocatalysis are low energy requirements and mild temperatures of purification leading to practically complete elimination of the substrate. Due to immobilization, cells and enzymes constitute an independent component which can be added to any continuously operating system of purification without generating a specific interface which is crucially important in microgravity. This allows the process of purification to be controllable. The resulting water and air meet biological requirements because they are formed under the influence of living organisms as in natural biogeocenoses. The production of ecologically pure water and air is highly important for long-duration space missions, especially for flights to Mars.

  1. Physico-chemical Modification of the Fibrous Filter Nozzles for Purification Processes of Water and Air

    NASA Astrophysics Data System (ADS)

    Bordunov, S. V.; Galtseva, O. V.; Natalinova, N. M.; Rogachev, A. A.; Zhang, Ruizhi

    2017-01-01

    A set of experiments to study physical and chemical modification of the surface of fibers is conducted to expand the area of their application for purification of water, gas and air (including that in conditions of space). The possibility of modification of filter nozzles in the process of fiber formation by particles of coal of BAU type, copper sulfide and silver chloride is experimentally shown. The fraction of the copper sulfide powder less than 50 microns in size was crushed in a spherical mill; it was deposited on fiber at air temperature of 50° C and powder consumption of 0.5 g/l of air. The resulting material contained 6–18 CuS particles per 1 cm of the fiber length. An effective bactericidal fibrous material can be produced using rather cheap material – CuS and relatively cheap natural compounds of sulphides and oxides of heavy metals.

  2. Soil-based filtration technology for air purification: potentials for environmental and space life support application

    NASA Astrophysics Data System (ADS)

    Nelson, Mark; Bohn, Hinrich

    Soil biofiltration, also known as Soil bed reactor (SBR), technology was originally developed in Germany to take advantage of the diversity in microbial mechanisms to control gases producing malodor in industrial processes. The approach has since gained wider international acceptance and seen numerous improvements, for example, by the use of high-organic compost beds to maximize microbial processes. This paper reviews the basic mechanisms which underlay soil processes involved in air purification, advantages and limitations of the technology and the cur-rent research status of the approach. Soil biofiltration has lower capital and operating/energetic costs than conventional technologies and is well adapted to handle contaminants in moderate concentrations. The systems can be engineered to optimize efficiency though manipulation of temperature, pH, moisture content, soil organic matter and airflow rates. SBR technology was modified for application in the Biosphere 2 project, which demonstrated in preparatory research with a number of closed system testbeds that soil could also support crop plants while also serving as soil filters with air pumps to push air through the soil. This Biosphere 2 research demonstrated in several closed system testbeds that a number of important trace gases could be kept under control and led to the engineering of the entire agricultural soil of Biosphere 2 to serve as a soil filtration unit for the facility. Soil biofiltration, coupled with food crop produc-tion, as a component of bioregenerative space life support systems has the advantages of lower energy use and avoidance of the consumables required for other air purification approaches. Expanding use of soil biofiltration can aid a number of environmental applications, from the mitigation of indoor air pollution, improvement of industrial air emissions and prevention of accidental release of toxic gases.

  3. Air Stripping Designs and Reactive Water Purification Processes for the Lunar Surface

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

    Air stripping designs are considered to reduce the presence of volatile organic compounds in the purified water. 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. Distillation processes are modeled in tandem with air stripping to demonstrate the potential effectiveness and utility of these methods in recycling wastewater on the Moon. 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. An evaluation of reactive distillation and 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.

  4. Slip-Effect Functional Air Filter for Efficient Purification of PM2.5

    PubMed Central

    Zhao, Xinglei; Wang, Shan; Yin, Xia; Yu, Jianyong; Ding, Bin

    2016-01-01

    Fabrication of air filtration materials (AFM) that allow air to easily flow through while retaining particles is a significant and urgent need due to the harmful airborne particulate matter pollution; however, this is still a challenging research area. Herein, we report novel slip-effect functional nanofibrous membranes with decreased air resistance (reduction rate of 40%) due to the slip flow of air molecules on the periphery of nanofibers. This was achieved through careful control over the diameters of electrospun polyacrylonitrile fibers and aperture size of fiber assembly. Fiber assembly with 86% of fiber diameters between 60–100 nm was found to be most effective for slip flow, as these diameters are close to the mean free path of air molecules (65.3 nm). Significantly, an equilibrium factor τ = df/d2 has been introduced to elucidate the effect of distance of adjacent fibers on the drag force of airflow. Furthermore, the most effective aperture size (>3.5 μm) for slip-effect has been determined. Ultimately, the new material displayed low air resistance of 29.5 Pa, high purification efficiency of 99.09%, good transmittance of 77%, and long service life. The successful fabrication of such materials can facilitate the development of high-performance AFMs for various applications. PMID:27748419

  5. Slip-Effect Functional Air Filter for Efficient Purification of PM2.5

    NASA Astrophysics Data System (ADS)

    Zhao, Xinglei; Wang, Shan; Yin, Xia; Yu, Jianyong; Ding, Bin

    2016-10-01

    Fabrication of air filtration materials (AFM) that allow air to easily flow through while retaining particles is a significant and urgent need due to the harmful airborne particulate matter pollution; however, this is still a challenging research area. Herein, we report novel slip-effect functional nanofibrous membranes with decreased air resistance (reduction rate of 40%) due to the slip flow of air molecules on the periphery of nanofibers. This was achieved through careful control over the diameters of electrospun polyacrylonitrile fibers and aperture size of fiber assembly. Fiber assembly with 86% of fiber diameters between 60–100 nm was found to be most effective for slip flow, as these diameters are close to the mean free path of air molecules (65.3 nm). Significantly, an equilibrium factor τ = df/d2 has been introduced to elucidate the effect of distance of adjacent fibers on the drag force of airflow. Furthermore, the most effective aperture size (>3.5 μm) for slip-effect has been determined. Ultimately, the new material displayed low air resistance of 29.5 Pa, high purification efficiency of 99.09%, good transmittance of 77%, and long service life. The successful fabrication of such materials can facilitate the development of high-performance AFMs for various applications.

  6. Plasma flame for mass purification of contaminated air with chemical and biological warfare agents

    SciTech Connect

    Uhm, Han S.; Shin, Dong H.; Hong, Yong C.

    2006-09-18

    An elimination of airborne simulated chemical and biological warfare agents was carried out by making use of a plasma flame made of atmospheric plasma and a fuel-burning flame, which can purify the interior air of a large volume in isolated spaces such as buildings, public transportation systems, and military vehicles. The plasma flame generator consists of a microwave plasma torch connected in series to a fuel injector and a reaction chamber. For example, a reaction chamber, with the dimensions of a 22 cm diameter and 30 cm length, purifies an airflow rate of 5000 lpm contaminated with toluene (the simulated chemical agent) and soot from a diesel engine (the simulated aerosol for biological agents). Large volumes of purification by the plasma flame will free mankind from the threat of airborne warfare agents. The plasma flame may also effectively purify air that is contaminated with volatile organic compounds, in addition to eliminating soot from diesel engines as an environmental application.

  7. Plasma flame for mass purification of contaminated air with chemical and biological warfare agents

    NASA Astrophysics Data System (ADS)

    Uhm, Han S.; Shin, Dong H.; Hong, Yong C.

    2006-09-01

    An elimination of airborne simulated chemical and biological warfare agents was carried out by making use of a plasma flame made of atmospheric plasma and a fuel-burning flame, which can purify the interior air of a large volume in isolated spaces such as buildings, public transportation systems, and military vehicles. The plasma flame generator consists of a microwave plasma torch connected in series to a fuel injector and a reaction chamber. For example, a reaction chamber, with the dimensions of a 22cm diameter and 30cm length, purifies an airflow rate of 5000lpm contaminated with toluene (the simulated chemical agent) and soot from a diesel engine (the simulated aerosol for biological agents). Large volumes of purification by the plasma flame will free mankind from the threat of airborne warfare agents. The plasma flame may also effectively purify air that is contaminated with volatile organic compounds, in addition to eliminating soot from diesel engines as an environmental application.

  8. Ammonia nitrogen removal and recovery from acetylene purification wastewater by air stripping.

    PubMed

    Zhu, Lei; Dong, DeMing; Hua, XiuYi; Xu, Yang; Guo, ZhiYong; Liang, DaPeng

    2017-06-01

    Ammonia nitrogen (NH4-N) contaminated wastewater has posed a great threat to the safety of water resources. In this study, air stripping was employed to remove and recover NH4-N from acetylene purification wastewater (APW) in a polyvinylchloride manufacturing plant. Investigated parameters were initial APW pH, air flow rate, APW temperature and stripping time. The NH4-N removal by air stripping has been modeled and the overall volumetric mass transfer coefficient (KLa) of the stripping process has been calculated from the model equation obtained. In addition, the ability of H2SO4 solution to absorb the NH3 stripped was also investigated. The results indicated that under the experimental conditions, the APW temperature and its initial pH had significant effects on the NH4-N removal efficiency and the KLa, while the effects of other factors were relatively minor. The removal efficiency and residual concentration of NH4-N were about 91% and 12 mg/L, respectively, at the optimal operating conditions of initial APW pH of 12.0, air flow rate of 0.500 m(3)/(h·L), APW temperature of 60 °C and stripping time of 120 min. One volume of H2SO4 solution (0.2 mol/L) could absorb about 93% of the NH3 stripped from 54 volumes of the APW.

  9. Purification Effects of Golden Pothos and Peace Lily for Indoor Air-Pollutants and its Application to a Real Environment

    NASA Astrophysics Data System (ADS)

    Sawada, Ayako; Yoshida, Taketoshi; Kuroda, Hiroyuki; Oyabu, Takashi; Takenaka, Kozaburo

    Plant has the capability to remediate the earth environment. Especially, it has high purification capability for air-pollution. In this paper, the capabilities of golden pothos and peace lily were examined. The subjects were planted in a plant pot. In the experiment, these subjects were installed in an experimental chamber of 300 liters respectively and the purification characteristics were monitored by a tin oxide gas sensor. The responding characteristic of the sensor, which means a plant purification capability, keeps the first order system which is used in the automatic control. Therefore, the time constant is employed to evaluate the plant capability. The capabilities of golden pothos and peace lily for formaldehyde, toluene and xylene were nearly constant even if the concentrations were changed. The capability of golden pothos for formaldehyde was 1.5 times higher than the one of peace lily. The capability of peace lily for toluene was 1.2 times as high as the one of golden pothos. The capabilities of golden pothos and peace lily for xylene were almost equal. It was also understood that the purification capability became lower as the molecular weight of the pollutant was larger. Plants were also set in a real environment. Total Volatile Organic Compounds (TVOC) and odors were measured to examine purification effect of plants. As for the results, removal rate for TVOC was 74% and the one for odor was 68%. It was confirmed that plants also had high purification capability in the real environment.

  10. Test Operations Procedure (TOP) 08-2-197 Chemical Protection Testing of Sorbent-Based Air Purification Components (APCs)

    DTIC Science & Technology

    2016-06-24

    based on the nature of the BFC, its prevalence on the battlefield, and potential interactions with the filtration media. If possible, a single design...3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Test Operations Procedure (TOP) 08-2-197 Chemical Protection Testing of Sorbent- Based Air...Operations Procedure (TOP) provides preparation, planning, conducting, and reporting procedures for testing sorbent- based air purification components (APCs

  11. Development and characterization of oxidation catalysts for air purification. Contractor report, August 1984-September 1985

    SciTech Connect

    Lester, G.R.; Marinangeli, R.E.

    1987-02-01

    The objective of this project was the development and characterization of low-temperature catalysts for removal of toxic chemical agents from air. Collective protection systems are being developed that depend on the catalytic destruction of chemical and biological agents. This method of air purification offers several potential advantages over conventional absorption systems, but successful development will require highly active catalysts which can function at temperatures as low as 250 C in order to minimize weight, volume, and energy requirements. The objective of this research has been the identification of such catalysts by the determination of the important catalyst characteristics that affect the rate of destruction of a wide range of chemical agents and agent simulants, including cyanogen chloride (CK), hydrogen cyanide (AC), phosgene (CG), and dimethyl methylphosphonate (DMMP), by catalytic oxidation and/or hydrolysis. Catalytic destruction of CG was achieved at temperatures as low as 75 C and of CK as low as 150 C. The best catalysts identified for conversion of AC and DMMP showed high initial activity at 250 C.

  12. Applied Technology of Bamboo Charcoal to Improvement and Purification of Air Quality

    NASA Astrophysics Data System (ADS)

    Takimoto, Akira; Tada, Yukio; Onishi, Hajime; Fukazawa, Tomohiro

    The use of bamboo charcoal, which is one of the carbon from wood, attracts attention from the viewpoint of the environmental protection. Bamboo charcoal has high adsorption removal ability to various substances. In addition Bamboo charcoal is effective also for the filtration of the suspended solid and the bacterium by the macro pore that originates in the plant frame structure. In present paper, a new concept of gas clean technology by bamboo charcoal and TiO2 with UV light irradiation was proposed. Its system is composed of TiO2-coated bamboo charcoal, TiO2-coated silica gel and UV lamp. Water vapor is adsorbed by bamboo charcoal and fine particles and airborne bacterium are trapped on the surface of it. Trapped contaminant is degraded by TiO2 and UV light. In addition, the degradation is promoted by •OH produced by adsorbed water vapor. The air purification sanitization possibility in high efficiency for this system was clarified.

  13. An investigation of an underwater steam plasma discharge as alternative to air plasmas for water purification

    NASA Astrophysics Data System (ADS)

    Gucker, Sarah N.; Foster, John E.; Garcia, Maria C.

    2015-10-01

    An underwater steam plasma discharge, in which water itself is the ionizing media, is investigated as a means to introduce advanced oxidation species into contaminated water for the purpose of water purification. The steam discharge avoids the acidification observed with air discharges and also avoids the need for a feed gas, simplifying the system. Steam discharge operation did not result in a pH changes in the processing of water or simulated wastewater, with the actual pH remaining roughly constant during processing. Simulated wastewater has been shown to continue to decompose significantly after steam treatment, suggesting the presence of long-lived plasma produced radicals. During steam discharge operation, nitrate production is limited, and nitrite production was found to be below the detection threshold of (roughly 0.2 mg L-1). The discharge was operated over a broad range of deposited power levels, ranging from approximately 30 W to 300 W. Hydrogen peroxide production was found to scale with increasing power. Additionally, the hydrogen peroxide production efficiency of the discharge was found to be higher than many of the rates reported in the literature to date.

  14. Exhaust gas purification device

    SciTech Connect

    Fujiwara, H.; Hibi, T.; Sayo, S.; Sugiura, Y.; Ueda, K.

    1980-02-19

    The exhaust gas purification device includes an exhaust manifold , a purification cylinder connected with the exhaust manifold through a first honey-comb shaped catalyst, and a second honeycomb shaped catalyst positioned at the rear portion of the purification cylinder. Each catalyst is supported by steel wool rings including coarse and dense portions of steel wool. The purification device further includes a secondary air supplying arrangement.

  15. Low Cost, Efficient Microcavity Plasma Ozone Generation for Water Remediation and Air Purification

    DTIC Science & Technology

    2012-06-01

    this entire test, the reactor was not cooled (intentionally, running at ~50C) and the microchannels were driven with fast, high voltage pulses in an...purification. Arrays of microchannel devices having a cross-sectional dimension of less than a few hundred microns were fabricated to generate... microchannels ~ 2.2 cm in length (Figure 2) but the electrode and dielectric structures yield different results. Figure 3 summarizes the results of

  16. Regeneration of an activated carbon bed by electyrothermal induction: Application to the purification of VOC charged air

    SciTech Connect

    Hauck, W.; Lamine, A.S.; Grevillot, G.

    1996-12-31

    Due to its affinity for organic substances, activated carbon is used to eliminate VOCs in gas streams. Adsorption isotherms are measured for toluene, the representative component of a current air purification problem. A major subject in this paper is the regeneration of spent activated carbon by inductive heating. This requires knowledge of the heat transfer in the activated carbon bed. Temperature profiles, allowing the calculation of the dissipated power, are measured. The obtained results allow a simulation of heat transfer in the bed using a pseudo-homogeneous model. The solution of the Maxwell equations for both the bed and a single grain allows the theoretical calculation of inductive heating based on the physical properties of the activated carbon bed. 8 refs., 5 figs., 1 tab.

  17. Photocatalytic removal of NO and HCHO over nanocrystalline Zn2SnO4 microcubes for indoor air purification.

    PubMed

    Ai, Zhihui; Lee, Shuncheng; Huang, Yu; Ho, Wingkei; Zhang, Lizhi

    2010-07-15

    Nanocrystalline Zn(2)SnO(4) microcubes were hydrothermally synthesized and systematically characterized by XRD, SEM, TEM, XPS, N(2) adsorption-desorption, and UV-vis DRS analysis. The resulting Zn(2)SnO(4) microcubes with the edge size ranging from 0.8 to 1.2 microm were composed of numerous nanoparticles with size of 10-20 nm, and their optical band gap energy was estimated to be 3.25 eV from the UV-vis diffuse reflectance spectra. On degradation of nitrogen monoxide (NO) and formaldehyde (HCHO) at typical concentrations for indoor air quality, these nanocrystalline Zn(2)SnO(4) microcubes exhibited superior photocatalytic activity to the hydrothermally synthesized ZnO, SnO(2), and Degussa TiO(2) P25, as well as C doped TiO(2) under UV-vis light irradiation. This enhanced photocatalytic activity of the nanocrystalline Zn(2)SnO(4) microcubes was attributed to their bigger surface areas, smaller particle size, special porous structures, and special electronic configuration. The nanocrystalline Zn(2)SnO(4) microcubes were chemically stable as there was no obvious deactivation during the multiple photocatalytic reactions. This work presents a promising approach for scaling-up industrial production of Zn(2)SnO(4) nanostructures and suggests that the synthesized nanocrystalline Zn(2)SnO(4) microcubes are promising photocatalysts for indoor air purification. 2010 Elsevier B.V. All rights reserved.

  18. Assessment of internal contamination problems associated with bioregenerative air/water purification systems

    NASA Technical Reports Server (NTRS)

    Johnson, Anne H.; Bounds, B. Keith; Gardner, Warren

    1990-01-01

    The emphasis is to characterize the mechanisms of bioregenerative revitalization of air and water as well as to assess the possible risks associated with such a system in a closed environment. Marsh and aquatic plants are utilized for purposes of wastewater treatment as well as possible desalinization and demineralization. Foliage plants are also being screened for their ability to remove toxic organics from ambient air. Preliminary test results indicate that treated wastewater is typically of potable quality with numbers of pathogens such as Salmonella and Shigella significantly reduced by the artificial marsh system. Microbiological analyses of ambient air indicate the presence of bacilli as well as thermophilic actinomycetes.

  19. Assessment of internal contamination problems associated with bioregenerative air/water purification systems

    NASA Technical Reports Server (NTRS)

    Johnson, Anne H.; Bounds, B. Keith; Gardner, Warren

    1990-01-01

    The emphasis is to characterize the mechanisms of bioregenerative revitalization of air and water as well as to assess the possible risks associated with such a system in a closed environment. Marsh and aquatic plants are utilized for purposes of wastewater treatment as well as possible desalinization and demineralization. Foliage plants are also being screened for their ability to remove toxic organics from ambient air. Preliminary test results indicate that treated wastewater is typically of potable quality with numbers of pathogens such as Salmonella and Shigella significantly reduced by the artificial marsh system. Microbiological analyses of ambient air indicate the presence of bacilli as well as thermophilic actinomycetes.

  20. A technique of purification process of single-walled carbon nanotubes with air.

    PubMed

    Song, Xin; Fang, Yan

    2007-07-01

    A technique of purifying SWCNTs has been developed by means of oxidizing carbonaceous particles with air using fluidized-bed. Air was introduced into the fluidized-bed by pump with controllable flux. The powders were "boiling" at a temperature of 550 degrees C for 50 min. With this technique, the flux can be controlled simply. The fluidized-bed was applied as the heating apparatus instead of rotated quartz tubes. The air and the powders can be mixed with each other more sufficiently. Characteristics of the raw and purified powder were presented using Raman spectroscopy and transmission electronic microscopy (TEM), revealing that the purified powder is free from carbonaceous particles.

  1. Dry purification of aspirational air in coke-sorting systems with wet slaking of coke

    SciTech Connect

    T.F. Trembach; A.G. Klimenko

    2009-07-15

    Coke transportation after wet slaking is accompanied by the release of dust in the production building and in the surrounding atmosphere. Wet methods are traditionally used to purify very humid air. Giprokoks has developed designs for highly efficient dry dust-removal methods in such conditions.

  2. Artificial intelligence modeling to evaluate field performance of photocatalytic asphalt pavement for ambient air purification.

    PubMed

    Asadi, Somayeh; Hassan, Marwa; Nadiri, Ataallah; Dylla, Heather

    2014-01-01

    In recent years, the application of titanium dioxide (TiO₂) as a photocatalyst in asphalt pavement has received considerable attention for purifying ambient air from traffic-emitted pollutants via photocatalytic processes. In order to control the increasing deterioration of ambient air quality, urgent and proper risk assessment tools are deemed necessary. However, in practice, monitoring all process parameters for various operating conditions is difficult due to the complex and non-linear nature of air pollution-based problems. Therefore, the development of models to predict air pollutant concentrations is very useful because it can provide early warnings to the population and also reduce the number of measuring sites. This study used artificial neural network (ANN) and neuro-fuzzy (NF) models to predict NOx concentration in the air as a function of traffic count (Tr) and climatic conditions including humidity (H), temperature (T), solar radiation (S), and wind speed (W) before and after the application of TiO₂ on the pavement surface. These models are useful for modeling because of their ability to be trained using historical data and because of their capability for modeling highly non-linear relationships. To build these models, data were collected from a field study where an aqueous nano TiO₂ solution was sprayed on a 0.2-mile of asphalt pavement in Baton Rouge, LA. Results of this study showed that the NF model provided a better fitting to NOx measurements than the ANN model in the training, validation, and test steps. Results of a parametric study indicated that traffic level, relative humidity, and solar radiation had the most influence on photocatalytic efficiency.

  3. Photocatalysis for continuous air purification in wastewater treatment plants: from lab to reality.

    PubMed

    Portela, R; Tessinari, R F; Suárez, S; Rasmussen, S B; Hernández-Alonso, M D; Canela, M C; Avila, P; Sánchez, B

    2012-05-01

    The photocatalytic efficiency of TiO(2)-SiMgO(x) plates to oxidize H(2)S was first evaluated in a flat laboratory reactor with 50 mL min(-1) synthetic air containing 100 ppm H(2)S in the presence of humidity. The use of the photocatalyst-adsorbent hybrid material enhanced the photocatalytic activity in terms of pollutant conversion, selectivity, and catalyst lifetime compared to previous H(2)S tests with pure TiO(2) because total H(2)S elimination was maintained for more than 30 operating hours with SO(2) appearing in the outlet as reaction product only after 18 h. Subsequently, the hybrid material was successfully tested in a photoreactor prototype to treat real polluted air in a wastewater treatment plant. For this purpose, a new tubular photocatalytic reactor that may use solar radiation in combination with artificial radiation was designed; the lamp was turned on when solar UV-A irradiance was below 20 W m(-2), which was observed to be the minimum value to ensure 100% conversion. The efficient distribution of the opaque photocatalyst inside the tubular reactor was achieved by using especially designed star-shaped structures. These structures were employed for the arrangement of groups of eight TiO(2)-SiMgO(x) plates in easy-to-handle channelled units obtaining an adequate flow regime without shading. The prototype continuously removed during one month and under real conditions the H(2)S contained in a 1 L min(-1) air current with a variable inlet concentration in the range of tens of ppmv without release of SO(2).

  4. Heterogeneous photocatalytic oxidation of organics for air purification by near UV irradiated titanium dioxide.

    PubMed

    Hager, S; Bauer, R

    1999-03-01

    The photocatalytic degradation of high concentrations of various organic pollutants (acetone, 2-propanol and toluene) in dry and humid air streams was carried out using a specially designed photoreactor based on the UV-TiO2 principle. The influence of several parameters which control the destruction efficiency (flow rate, initial contaminant and water vapour concentration, temperature and light intensity) has been studied. The conversion was maximal at room temperature, low flow rates and low initial contaminant concentrations. The presence of water in the inlet stream strongly affected the performance of the catalyst. The primary oxidation product of 2-propanol was acetone.

  5. Air purification from TCE and PCE contamination in a hybrid bioreactors and biofilter integrated system.

    PubMed

    Tabernacka, Agnieszka; Zborowska, Ewa; Lebkowska, Maria; Borawski, Maciej

    2014-01-15

    A two-stage waste air treatment system, consisting of hybrid bioreactors (modified bioscrubbers) and a biofilter, was used to treat waste air containing chlorinated ethenes - trichloroethylene (TCE) and tetrachloroethylene (PCE). The bioreactor was operated with loadings in the range 0.46-5.50gm(-3)h(-1) for TCE and 2.16-9.02gm(-3)h(-1) for PCE. The biofilter loadings were in the range 0.1-0.97gm(-3)h(-1) for TCE and 0.2-2.12gm(-3)h(-1) for PCE. Under low pollutant loadings, the efficiency of TCE elimination was 23-25% in the bioreactor and 54-70% in the biofilter. The efficiency of PCE elimination was 44-60% in the bioreactor and 50-75% in the biofilter. The best results for the bioreactor were observed one week after the pollutant loading was increased. However, the process did not stabilize. In the next seven days contaminant removal efficiency, enzymatic activity and biomass content were all diminished. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Design approaches for a cycling adsorbent/photocatalyst system for indoor air purification: formaldehyde example.

    PubMed

    Chin, Paul; Ollis, David F

    2008-04-01

    A kinetic model for a cycling adsorbent/photocatalyst combination for formaldehyde removal in indoor air (Chin et al. J. Catalysis 2006, 237, 29-37) was previously developed in our lab, demonstrating agreement with lab-scale batch operation data of other researchers (Shiraishi et al. Chem. Engineer. Sci. 2003, 58, 929-934). Model parameters evaluated included adsorption equilibrium and rate constants for the adsorbent (activated carbon) honeycomb rotor, and catalytic rate constant for pseudo-first-order formaldehyde destruction in the titanium dioxide photoreactor. This paper explores design consequences for this novel system. In particular, the batch parameter values are used to model both adsorbent and photocatalyst behavior for continuous operation in typical residential home challenges. Design variables, including realistic make-up air fraction, adsorbent honeycomb rotation speed, and formaldehyde source emission rate, are considered to evaluate the ability of the system to achieve World Health Organization pollutant guidelines. In all circumstances, the size of the required rotating adsorbent bed and photoreactor for single-stage operation and the resultant formaldehyde concentration in the home are calculated. The ability of how well such a system might be accommodated within the typical dimensions of commercial ventilation ducts is also considered.

  7. Are TiO2 nanotubes worth using in photocatalytic purification of air and water?

    PubMed

    Pichat, Pierre

    2014-09-19

    Titanium dioxide nanotubes (TNT) have mainly been used in dye sensitized solar cells, essentially because of a higher transport rate of electrons from the adsorbed photo-excited dye to the Ti electrode onto which TNT instead of TiO2 nanoparticles (TNP) are attached. The dimension ranges and the two main synthesis methods of TNT are briefly indicated here. Not surprisingly, the particular and regular texture of TNT was also expected to improve the photocatalytic efficacy for pollutant removal in air and water with respect to TNP. In this short review, the validity of this expectation is checked using the regrettably small number of literature comparisons between TNT and commercialized TNP referring to films of similar thickness and layers or slurries containing an equal TiO2 mass. Although the irradiated geometrical area differed for each study, it was identical for each comparison considered here. For the removal of toluene (methylbenzene) or acetaldehyde (ethanal) in air, the average ratio of the efficacy of TNT over that of TiO2 P25 was about 1.5, and for the removal of dyes in water, it was around 1. This lack of major improvement with TNT compared to TNP could partially be due to TNT texture disorders as seems to be suggested by the better average performance of anodic oxidation-prepared TNT. It could also come from the fact that the properties influencing the efficacy are more numerous, their interrelations more complex and their effects more important for pollutant removal than for dye sensitized solar cells and photoelectrocatalysis where the electron transport rate is the crucial parameter.

  8. House-plant placement for indoor air purification and health benefits on asthmatics.

    PubMed

    Kim, Ho-Hyun; Yang, Ji-Yeon; Lee, Jae-Young; Park, Jung-Won; Kim, Kwang-Jin; Lim, Byung-Seo; Lee, Geon-Woo; Lee, Si-Eun; Shin, Dong-Chun; Lim, Young-Wook

    2014-01-01

    Some plants were placed in indoor locations frequented by asthmatics in order to evaluate the quality of indoor air and examine the health benefits to asthmatics. The present study classified the participants into two groups: households of continuation and households of withdrawal by a quasi-experimental design. The households of continuation spent the two observation terms with indoor plants, whereas the households of withdrawal passed the former observation terms with indoor plants and went through the latter observation term without any indoor plants. The household of continuation showed a continual decrease in the indoor concentrations of volatile organic compounds (VOCs) during the entire observation period, but the household of withdrawal performed an increase in the indoor concentrations of VOCs, except formaldehyde and toluene during the latter observation term after the decrease during the former observation term. Peak expiratory flow rate (PEFR) increased in the households of continuation with the value of 13.9 L/min in the morning and 20.6 L/ min in the evening, but decreased in the households of withdrawal with the value of -24.7 L/min in the morning and -30.2 L/min in the evening in the first experimental season. All of the households exhibited a decrease in the value of PEFR in the second experimental season. Limitations to the generalizability of findings regarding the presence of plants indoors can be seen as a more general expression of such a benefit of human-environment relations.

  9. Visible Light Responsive Catalysts Using Quantum Dot-Modified Ti02 for Air and Water Purification

    NASA Technical Reports Server (NTRS)

    Coutts, Janelle L.; Levine, Lanfang H.; Richards, Jeffrey T.; Hintze, paul; Clausen, Christian

    2012-01-01

    The method of photocatalysis utilizing titanium dioxide, TiO2, as the catalyst has been widely studied for trace contaminant control for both air and water applications because of its low energy consumption and use of a regenerable catalyst. Titanium dioxide requires ultraviolet light for activation due to its band gap energy of 3.2 eV. Traditionally, Hg-vapor fluorescent light sources are used in PCO reactors and are a setback for the technology for space application due to the possibility of Hg contamination. The development of a visible light responsive (VLR) TiO2-based catalyst could lead to the use of solar energy in the visible region (approx.45% of the solar spectrum lies in the visible region; > 400 nm) or highly efficient LEDs (with wavelengths > 400 nm) to make PCO approaches more efficient, economical, and safe. Though VLR catalyst development has been an active area of research for the past two decades, there are few commercially available VLR catalysts; those that are available still have poor activity in the visible region compared to that in the UV region. Thus, this study was aimed at the further development of VLR catalysts by a new method - coupling of quantum dots (QD) of a narrow band gap semiconductor (e.g., CdS, CdSe, PbS, ZnSe, etc.) to the TiO2 by two preparation methods: 1) photodeposition and 2) mechanical alloying using a high-speed ball mill. A library of catalysts was developed and screened for gas and aqueous phase applications, using ethanol and 4-chlorophenol as the target contaminants, respectively. Both target compounds are well studied in photocatalytic systems serve as model contaminants for this research. Synthesized catalysts were compared in terms of preparation method, type of quantum dots, and dosage of quantum dots.

  10. House-plant placement for indoor air purification and health benefits on asthmatics

    PubMed Central

    Kim, Ho-Hyun; Yang, Ji-Yeon; Lee, Jae-Young; Park, Jung-Won; Kim, Kwang-Jin; Lim, Byung-Seo; Lee, Geon-Woo; Lee, Si-Eun; Shin, Dong-Chun; Lim, Young-Wook

    2014-01-01

    Objectives Some plants were placed in indoor locations frequented by asthmatics in order to evaluate the quality of indoor air and examine the health benefits to asthmatics. Methods The present study classified the participants into two groups: households of continuation and households of withdrawal by a quasi-experimental design. The households of continuation spent the two observation terms with indoor plants, whereas the households of withdrawal passed the former observation terms with indoor plants and went through the latter observation term without any indoor plants. Results The household of continuation showed a continual decrease in the indoor concentrations of volatile organic compounds (VOCs) during the entire observation period, but the household of withdrawal performed an increase in the indoor concentrations of VOCs, except formaldehyde and toluene during the latter observation term after the decrease during the former observation term. Peak expiratory flow rate (PEFR) increased in the households of continuation with the value of 13.9 L/min in the morning and 20.6 L/ min in the evening, but decreased in the households of withdrawal with the value of -24.7 L/min in the morning and -30.2 L/min in the evening in the first experimental season. All of the households exhibited a decrease in the value of PEFR in the second experimental season. Conclusions Limitations to the generalizability of findings regarding the presence of plants indoors can be seen as a more general expression of such a benefit of human-environment relations. PMID:25384387

  11. PTR-MS assessment of photocatalytic and sorption-based purification of recirculated cabin air during simulated 7-h flights with high passenger density.

    PubMed

    Wisthaler, Armin; Strøm-Tejsen, Peter; Fang, Lei; Arnaud, Timothy J; Hansel, Armin; Märk, Tilmann D; Wyon, David P

    2007-01-01

    Four different air purification conditions were established in a simulated 3-row 21-seat section of an aircraft cabin: no air purifier; a photocatalytic oxidation unit with an adsorptive prefilter; a second photocatalytic unit with an adsorptive prefilter; and a two-stage sorption-based air filter (gas-phase absorption and adsorption). The air purifiers placed in the cabin air recirculation system were commercial prototypes developed for use in aircraft cabin systems. The four conditions were established in balanced order on 4 successive days of each of 4 successive weeks during simulated 7-h flights with 17 occupants. Proton-transfer reaction mass spectrometry was used to assess organic gas-phase pollutants and the performance of each air purifier. The concentration of most organic pollutants present in aircraft cabin air was efficiently reduced by all three units. The photocatalytic units were found to incompletely oxidize ethanol released by the wet wipes commonly supplied with airline mealsto produce unacceptably high levels of acetaldehyde and formaldehyde.

  12. Experimental investigation of the formaldehyde removal mechanisms in a dynamic botanical filtration system for indoor air purification.

    PubMed

    Wang, Zhiqiang; Pei, Jingjing; Zhang, Jensen S

    2014-09-15

    Botanical filtration has been proved to be effective for indoor gas pollutant removal. To understand the roles of different transport, storage and removal mechanism by a dynamic botanical air filter, a series of experimental investigations were designed and conducted in this paper. Golden Pothos (Epipremnum aureum) plants was selected for test, and its original soil or activated/pebbles root bed was used in different test cases. It was found that flowing air through the root bed with microbes dynamically was essential to obtain meaningful formaldehyde removal efficiency. For static potted plant as normally place in rooms, the clean air delivery rate (CADR), which is often used to quantify the air cleaning ability of portable air cleaners, was only ∼ 5.1m(3)/h per m(2) bed, while when dynamically with air flow through the bed, the CADR increased to ∼ 233 m(3)/h per m(2) bed. The calculated CADR due to microbial activity is ∼ 108 m(3)/h per m(2) bed. Moisture in the root bed also played an important role, both for maintaining a favorable living condition for microbes and for absorbing water-soluble compounds such as formaldehyde. The role of the plant was to introduce and maintain a favorable microbe community which effectively degraded the volatile organic compounds adsorbed or absorbed by the root bed. The presence of the plant increased the removal efficiency by a factor of two based on the results from the bench-scale root bed experiments.

  13. Portable neon purification system

    SciTech Connect

    Richardson, R.A.; Schmitt, R.L.

    1995-08-01

    This paper describes the principle design features of a portable neon purification system and the results of the system performance testing. Neon gas replaces air in the Ring Imaging Cherenkov detector without using vacuum, in experiment E781(SELEX) at Fermilab. The portable neon purification system purifies neon gas by, first purging air with CO{sub 2}, freezing the CO{sub 2}, then cryoadsorbing the remaining contaminants. The freezer removes carbon dioxide from a neon gas mixture down to a maximum concentration of 500 parts-per-million (ppm). The charcoal bed adsorber removes nitrogen from neon gas down to a maximum concentration of 100 ppm. The original RICH vessel was designed to hold vacuum but its photomultiplier tube plates were not.

  14. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  15. Visible-Light Responsive Catalysts Using Quantum Dot-Modified TiO2 for Air and Water Purification

    NASA Technical Reports Server (NTRS)

    Coutts, Janelle L.; Hintze, Paul E.; Clausen, Christian A.; Richards, Jeffrey T.

    2014-01-01

    Photocatalysis, the oxidation or reduction of contaminants by light-activated catalysts, utilizing titanium dioxide (TiO2) as the catalytic substrate has been widely studied for trace contaminant control in both air and water applications. The interest in this process is due primarily to its low energy consumption and capacity for catalyst regeneration. Titanium dioxide requires ultraviolet light for activation due to its relatively large band gap energy of 3.2 eV. Traditionally, Hg-vapor fluorescent light sources are used in PCO reactors; however, the use of mercury precludes the use of this PCO technology in a spaceflight environment due to concerns over crew Hg exposure.

  16. Hamiltonian purification

    SciTech Connect

    Orsucci, Davide; Burgarth, Daniel; Facchi, Paolo; Pascazio, Saverio; Nakazato, Hiromichi; Yuasa, Kazuya; Giovannetti, Vittorio

    2015-12-15

    The problem of Hamiltonian purification introduced by Burgarth et al. [Nat. Commun. 5, 5173 (2014)] is formalized and discussed. Specifically, given a set of non-commuting Hamiltonians (h{sub 1}, …, h{sub m}) operating on a d-dimensional quantum system ℋ{sub d}, the problem consists in identifying a set of commuting Hamiltonians (H{sub 1}, …, H{sub m}) operating on a larger d{sub E}-dimensional system ℋ{sub d{sub E}} which embeds ℋ{sub d} as a proper subspace, such that h{sub j} = PH{sub j}P with P being the projection which allows one to recover ℋ{sub d} from ℋ{sub d{sub E}}. The notions of spanning-set purification and generator purification of an algebra are also introduced and optimal solutions for u(d) are provided.

  17. Visible-Light-Responsive Catalysts Using Quantum Dot-Modified TiO2 for Air and Water Purification

    NASA Technical Reports Server (NTRS)

    Coutts, Janelle L.; Hintze, Paul E.; Clausen, Christian; Richards, Jeffrey Todd

    2014-01-01

    Photocatalysis, the oxidation or reduction of contaminants by light-activated catalysts, utilizing titanium dioxide (TiO2) as the catalytic substrate has been widely studied for trace contaminant control in both air and water applications. The interest in this process is due primarily to its low energy consumption and capacity for catalyst regeneration. Titanium dioxide requires ultraviolet light for activation due to its relatively large band gap energy of 3.2 eV. Traditionally, Hg-vapor fluorescent light sources are used in PCO reactors; however, the use of mercury precludes the use of this PCO technology in a spaceflight environment due to concerns over crew Hg exposure. The development of a visible-light responsive (VLR) TiO2-based catalyst would eliminate the concerns over mercury contamination. Further, VLR development would allow for the use of ambient visible solar radiation or highly efficient LEDs, both of which would make PCO approaches more efficient, flexible, economical, and safe. Though VLR catalyst development has been an active area of research for the past two decades, there are few commercially available VLR catalysts. Those VLR catalysts that are commercially available do not have adequate catalytic activity, in the visible region, to make them competitive with those operating under UV irradiation. This study was initiated to develop more effective VLR catalysts through a novel method in which quantum dots (QD) consisting of narrow band gap semiconductors (e.g., CdS, CdSe, PbS, ZnSe, etc.) are coupled to TiO2 via two preparation methods: 1) photodeposition and 2) mechanical alloying using a high-speed ball mill. A library of catalysts was developed and screened for gas and aqueous phase applications using ethanol and 4-chlorophenol as the target contaminants, respectively. Both target compounds are well studied in photocatalytic systems and served as model contaminants for this research. Synthesized catalysts were compared in terms of

  18. Pool Purification

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Caribbean Clear, Inc. used NASA's silver ion technology as a basis for its automatic pool purifier. System offers alternative approach to conventional purification chemicals. Caribbean Clear's principal markets are swimming pool owners who want to eliminate chlorine and bromine. Purifiers in Caribbean Clear System are same silver ions used in Apollo System to kill bacteria, plus copper ions to kill algae. They produce spa or pool water that exceeds EPA Standards for drinking water.

  19. Polonium purification

    SciTech Connect

    Baker, J.D.

    1996-09-01

    Three processes for the purification of {sup 210}Po from irradiated bismuth targets are described. Safety equipment includes shielded hotcells for the initial separation from other activation products, gloveboxes for handling the volatile and highly toxic materials, and provisions for ventilation. All chemical separations must be performed under vacuum or in inerted systems. Two of the processes require large amounts of electricity; the third requires vessels made from exotic materials.

  20. Water Purification

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Silver ionization water purification technology was originally developed for Apollo spacecraft. It was later used to cleanse swimming pools and has now been applied to industrial cooling towers and process coolers. Sensible Technologies, Inc. has added two other technologies to the system, which occupies only six square feet. It is manufactured in three capacities, and larger models are custom built on request. The system eliminates scale, corrosion, algae, bacteria and debris, and because of the NASA technology, viruses and waterborne bacteria are also destroyed. Applications include a General Motors cooling tower, amusement parks, ice manufacture and a closed-loop process cooling system.

  1. PURIFICATION PROCESS

    DOEpatents

    Wibbles, H.L.; Miller, E.I.

    1958-01-14

    This patent deals with the separation of uranium from molybdenum compounds, and in particular with their separation from ether solutions containing the molybdenum in the form of acids, such as silicomolybdic and phosphomolybdic acids. After the nitric acid leach of pitchblende, the molybdenum values present in the ore are found in the leach solution in the form of complex acids. The uranium bearing solution may be purified of this molybdenum content by comtacting it with activated charcoal. The purification is improved when the acidity of the solution is low ad agitation is also beneficial. The molybdenum may subsequently be recovered from the charcosl ad the charcoal reused.

  2. Thermochemical Analysis for Purification of Polysilicon Melts

    SciTech Connect

    Ho, Pauline: Gee, James M.

    1999-05-01

    Chemical Equilibrium calculations are presented that are relevant to the purification of molten silicon by gas-blowing. The equilibrium distributions of silicon, boron, phosphorus carbon and iron among the solid, liquid and gas phases are reported for a variety of added chemicals, temperatures and total pressures. The identities of the dominant chemical species for each element in each phase are also provided for these conditions. The added gases examined are O(2), air, water, wet air, HCl, Cl(2), Cl(2)/O(2), SiCl(4), NH(3), NH(4)OH, and NH(4)Cl. These calculations suggest possible purification schemes, although kinetic or transport limitations may prove to be significant

  3. Hydrogen gas purification apparatus

    SciTech Connect

    Yanagihara, N.; Gamo, T.; Iwaki, T.; Moriwaki, Y.

    1984-04-24

    A hydrogen gas purification apparatus which includes at least one set of two hydrogen purification containers coupled to each other for heat exchanging therebetween, each of the hydrogen purification containers containing a hydrogen absorbing alloy. The hydrogen gas purification apparatus is so arranged as to cause hydrogen gas to be selectively desorbed from and absorbed into the hydrogen absorbing alloy by the amount of heat produced when the hydrogen gas is selectively absorbed into and desorbed from the hydrogen absorbing alloy.

  4. Lindbladian purification

    NASA Astrophysics Data System (ADS)

    Arenz, Christian; Burgarth, Daniel; Giovannetti, Vittorio; Nakazato, Hiromichi; Yuasa, Kazuya

    2017-06-01

    In a recent work (Burgarth et al 2014, Nat. Commun. 5 5173), it was shown that a series of frequent measurements can project the dynamics of a quantum system onto a subspace in which the dynamics can be more complex. In this subspace, even full controllability can be achieved, although the controllability over the system before the projection is very poor since the control Hamiltonians commute with each other. We can also think of the opposite: any Hamiltonians of a quantum system, which are in general noncommutative with each other, can be made commutative by embedding them in an extended Hilbert space, thus the dynamics in the extended space becomes trivial and simple. This idea of making noncommutative Hamiltonians commutative is called ‘Hamiltonian purification.’ The original noncommutative Hamiltonians are recovered by projecting the system back onto the original Hilbert space through frequent measurements. Here, we generalise this idea to open-system dynamics by presenting a simple construction to make Lindbladians, as well as Hamiltonians, commutative on a larger space with an auxiliary system. We show that the original dynamics can be recovered through frequently measuring the auxiliary system in a non-selective way. Moreover, we provide a universal pair of Lindbladians that describe an ‘accessible’ open quantum system for generic system sizes. This allows us to conclude that through a series of frequent non-selective measurements a nonaccessible open quantum system generally becomes accessible. This sheds further light on the role of measurement backaction on the control of quantum systems.

  5. Purification process for vertically aligned carbon nanofibers

    NASA Technical Reports Server (NTRS)

    Nguyen, Cattien V.; Delziet, Lance; Matthews, Kristopher; Chen, Bin; Meyyappan, M.

    2003-01-01

    Individual, free-standing, vertically aligned multiwall carbon nanotubes or nanofibers are ideal for sensor and electrode applications. Our plasma-enhanced chemical vapor deposition techniques for producing free-standing and vertically aligned carbon nanofibers use catalyst particles at the tip of the fiber. Here we present a simple purification process for the removal of iron catalyst particles at the tip of vertically aligned carbon nanofibers derived by plasma-enhanced chemical vapor deposition. The first step involves thermal oxidation in air, at temperatures of 200-400 degrees C, resulting in the physical swelling of the iron particles from the formation of iron oxide. Subsequently, the complete removal of the iron oxide particles is achieved with diluted acid (12% HCl). The purification process appears to be very efficient at removing all of the iron catalyst particles. Electron microscopy images and Raman spectroscopy data indicate that the purification process does not damage the graphitic structure of the nanotubes.

  6. Air purification equipment combining a filter coated by silver nanoparticles with a nano-TiO2 photocatalyst for use in hospitals

    NASA Astrophysics Data System (ADS)

    Son Le, Thanh; Hien Dao, Trong; Nguyen, Dinh Cuong; Chau Nguyen, Hoai; Balikhin, I. L.

    2015-03-01

    X-ray diffraction, scanning electron microscopy and transmission electron microscopy showed that TiO2 particles synthesized by a sol-gel procedure exhibited uniform size about 16-20 nm. This nanopowder was deposited on a porous quartz tube (D = 74 mm, L = 418 mm, deposit density ˜16.4 mg cm-2) through an intermediate adhesive polymethylmethacrylate layer to manufacture a photocatalytic filter tube. A polypropylene pre-filter was coated with a nanosilver layer (particle size ˜20 nm) prepared by aqueous molecular solution method. An air cleaner of 250 m3 h-1 capacity equipped with this pre-filter, an electrostatic air filter, 4 photocatalytic filter tubes and 4 UV-A lamps (36 W) presented the high degradation ability for certain volatile organic compounds (VOCs), bacteria and fungi. The VOCs degradation performances of the equipment with respect to divers compounds are different: in a 10 m3 box, 91.6% of butanol was removed within 55 min, 80% of acetone within 100 min, 70.1% of diethyl ether within 120 min and only 43% of benzene was oxidized within 150 min. Over 99% of bacteria and fungi were killed after the air passage through the equipment. For application, it was placed in the intensive care room (volume of 125 m3) of E hospital in Hanoi; 69% of bacteria and 63% of fungi were killed within 6 h.

  7. Immobilization of polymeric g-C3N4 on structured ceramic foam for efficient visible light photocatalytic air purification with real indoor illumination.

    PubMed

    Dong, Fan; Wang, Zhenyu; Li, Yuhan; Ho, Wing-Kei; Lee, S C

    2014-09-02

    The immobilization of a photocatalyst on a proper support is pivotal for practical environmental applications. In this work, graphitic carbon nitride (g-C3N4) as a rising visible light photocatalyst was first immobilized on structured Al2O3 ceramic foam by a novel in situ approach. Immobilized g-C3N4 was applied for photocatalytic removal of 600 ppb level NO in air under real indoor illumination of an energy-saving lamp. The photocatalytic activity of immobilized g-C3N4 was gradually improved as the pyrolysis temperature was increased from 450 to 600 °C. The optimized conditions for g-C3N4 immobilization on Al2O3 supports can be achieved at 600 °C for 2 h. The NO removal ratio could reach up to 77.1%, exceeding that of other types of well-known immobilized photocatalysts. Immobilized g-C3N4 was stable in activity and can be used repeatedly without deactivation. The immobilization of g-C3N4 on Al2O3 ceramic foam was found to be firm enough to overwhelm the continuous air flowing, which can be ascribed to the special chemical interaction between g-C3N4 and Al2O3. On the basis of the 5,5'-dimethyl-1-pirroline-N-oxide electron spin resonance (DMPO ESR) spin trapping and reaction intermediate monitoring, the active species produced from g-C3N4 under illumination were confirmed and the reaction mechanism of photocatalytic NO oxidation by g-C3N4 was revealed. The present work could provide new perspectives for promoting large-scale environmental applications of supported photocatalysts.

  8. The Borexino purification system

    NASA Astrophysics Data System (ADS)

    Benziger, Jay

    2014-05-01

    Purification of 278 tons of liquid scintillator and 889 tons of buffer shielding for the Borexino solar neutrino detector is performed with a system of combined distillation, water extraction, gas stripping and filtration. The purification system removed K, U and Th by distillation of the pseudocumene solvent and the PPO fluor. Noble gases, Rn, Kr and Ar were removed by gas stripping. Distillation was also employed to remove optical impurities and reduce the attenuation of scintillation light. The success of the purification system has facilitated the first time real time detection of low energy solar neutrinos.

  9. Effect of chlorine purification on oxidation resistance of some mechanical carbons

    NASA Technical Reports Server (NTRS)

    Wisander, D. W.; Allen, G. P.

    1974-01-01

    Oxidation experiments were conducted with some experimental and commercial mechanical carbons at 650 C in dry air flowing at 28 cc/sec (STP). In general, purification of these carbon-graphites with chlorine at 2800 C improved oxidation resistance. Additional improvements in oxidation resistance were obtained from purification followed by an antioxidant (zinc phosphate) treatment. For the commercial materials, purification alone gave greater oxidation resistance than the antioxidant treatment alone. The reverse, however, was the case for the experimental materials.

  10. Air Pollution, Causes and Cures.

    ERIC Educational Resources Information Center

    Manufacturing Chemists Association, Washington, DC.

    This commentary on sources of air pollution and air purification treatments is accompanied by graphic illustrations. Sources of carbon monoxide, sulfur oxides, nitrogen oxides, and hydrocarbons found in the air are discussed. Methods of removing these pollutants at their source are presented with cut-away diagrams of the facilities and technical…

  11. Succinonitrile Purification Facility

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Succinonitrile (SCN) Purification Facility provides succinonitrile and succinonitrile alloys to several NRA selected investigations for flight and ground research at various levels of purity. The purification process employed includes both distillation and zone refining. Once the appropriate purification process is completed, samples are characterized to determine the liquidus and/or solidus temperature, which is then related to sample purity. The lab has various methods for measuring these temperatures with accuracies in the milliKelvin to tenths of milliKelvin range. The ultra-pure SCN produced in our facility is indistinguishable from the standard material provided by NIST to well within the stated +/- 1.5mK of the NIST triple point cells. In addition to delivering material to various investigations, our current activities include process improvement, characterization of impurities and triple point cell design and development. The purification process is being evaluated for each of the four vendors to determine the efficacy of each purification step. We are also collecting samples of the remainder from distillation and zone refining for analysis of the constituent impurities. The large triple point cells developed will contain SCN with a melting point of 58.0642 C +/- 1.5mK for use as a calibration standard for Standard Platinum Resistance Thermometers (SPRTs).

  12. Succinonitrile Purification Facility

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Succinonitrile (SCN) Purification Facility provides succinonitrile and succinonitrile alloys to several NRA selected investigations for flight and ground research at various levels of purity. The purification process employed includes both distillation and zone refining. Once the appropriate purification process is completed, samples are characterized to determine the liquidus and/or solidus temperature, which is then related to sample purity. The lab has various methods for measuring these temperatures with accuracies in the milliKelvin to tenths of milliKelvin range. The ultra-pure SCN produced in our facility is indistinguishable from the standard material provided by NIST to well within the stated +/- 1.5mK of the NIST triple point cells. In addition to delivering material to various investigations, our current activities include process improvement, characterization of impurities and triple point cell design and development. The purification process is being evaluated for each of the four vendors to determine the efficacy of each purification step. We are also collecting samples of the remainder from distillation and zone refining for analysis of the constituent impurities. The large triple point cells developed will contain SCN with a melting point of 58.0642 C +/- 1.5mK for use as a calibration standard for Standard Platinum Resistance Thermometers (SPRTs).

  13. Ribonucleic acid purification.

    PubMed

    Martins, R; Queiroz, J A; Sousa, F

    2014-08-15

    Research on RNA has led to many important biological discoveries and improvement of therapeutic technologies. From basic to applied research, many procedures employ pure and intact RNA molecules; however their isolation and purification are critical steps because of the easy degradability of RNA, which can impair chemical stability and biological functionality. The current techniques to isolate and purify RNA molecules still have several limitations and the requirement for new methods able to improve RNA quality to meet regulatory demands is growing. In fact, as basic research improves the understanding of biological roles of RNAs, the biopharmaceutical industry starts to focus on them as a biotherapeutic tools. Chromatographic bioseparation is a high selective unit operation and is the major option in the purification of biological compounds, requiring high purity degree. In addition, its application in biopharmaceutical manufacturing is well established. This paper discusses the importance and the progress of RNA isolation and purification, considering RNA applicability both in research and clinical fields. In particular and in view of the high specificity, affinity chromatography has been recently applied to RNA purification processes. Accordingly, recent chromatographic investigations based on biorecognition phenomena occurring between RNA and amino acids are focused. Histidine and arginine have been used as amino acid ligands, and their ability to isolate different RNA species demonstrated a multipurpose applicability in molecular biology analysis and RNA therapeutics preparation, highlighting the potential contribution of these methods to overcome the challenges of RNA purification.

  14. Purification of genuine multipartite entanglement

    SciTech Connect

    Huber, Marcus; Plesch, Martin

    2011-06-15

    In tasks where multipartite entanglement plays a central role, state purification is, due to inevitable noise, a crucial part of the procedure. We consider a scenario exploiting the multipartite entanglement in a straightforward multipartite purification algorithm and compare it to bipartite purification procedures combined with state teleportation. While complete purification requires an infinite amount of input states in both cases, we show that for an imperfect output fidelity the multipartite procedure exhibits a major advantage in terms of input states used.

  15. Application of high energy chemistry methods for purification of water and air (on the basis of the materials of the I International Conference on Advanced Oxidation Technologies for Water and Air Remediation)

    SciTech Connect

    Pikaev, A.K.

    1995-01-01

    The I International Conference on Advanced Oxidation Technologies for Water and Air Remediation was held from June 25-30, 1994, in London (province of Ontario, Canada). Dr. H. Al-Ekabi (Canada) was the chairman of Organizing Committee. Over 350 specialists from Russia, USA, Canada, Japan, Germany, France, Italy, Great Britain, Poland, Switzerland, Holland, People`s Republic of China, Austria, Finland, South Korea, Spain, Hong Kong, Denmark, Taiwan, Belgium, and Iraq took part. During the conference there was also an exhibition, at which several companies demonstrated products which were related to the themes of the conference. About 200 invited and contributed reports and poster communications were presented, evaluated and discussed. There were also three panel discussions about governmental ecological programs, the transfer of oxidation technologies, etc.

  16. Fully automated protein purification

    PubMed Central

    Camper, DeMarco V.; Viola, Ronald E.

    2009-01-01

    Obtaining highly purified proteins is essential to begin investigating their functional and structural properties. The steps that are typically involved in purifying proteins can include an initial capture, intermediate purification, and a final polishing step. Completing these steps can take several days and require frequent attention to ensure success. Our goal was to design automated protocols that will allow the purification of proteins with minimal operator intervention. Separate methods have been produced and tested that automate the sample loading, column washing, sample elution and peak collection steps for ion-exchange, metal affinity, hydrophobic interaction and gel filtration chromatography. These individual methods are designed to be coupled and run sequentially in any order to achieve a flexible and fully automated protein purification protocol. PMID:19595984

  17. Water purification in Borexino

    SciTech Connect

    Giammarchi, M.; Balata, M.; Ioannucci, L.; Nisi, S.; Goretti, A.; Ianni, A.; Miramonti, L.

    2013-08-08

    Astroparticle Physics and Underground experiments searching for rare nuclear events, need high purity materials to act as detectors or detector shielding. Water has the advantage of being cheap, dense and easily available. Most of all, water can be purified to the goal of obatining a high level of radiopurity. Water Purification can be achieved by means of a combination of processes, including filtration, reverse osmosis, deionization and gas stripping. The Water Purification System for the Borexino experiment, will be described together with its main performances.

  18. Functionalized Organosilicate Sorbents for Air Purification

    DTIC Science & Technology

    2013-12-23

    sorbents ...................................................................................... 20 Fig. 17 Chlorine breakthrough for E50 sorbents...32 Fig. 30 Chlorine and nitric oxide breakthrough... Chlorine breakthrough for NiC1S3-ED13 ................................................................................. 35 Fig. 34 Target

  19. Blood purification for intoxication.

    PubMed

    Nakae, Hajime

    2010-01-01

    Blood purification is administered in cases of acute intoxication when the substance causing the intoxication is to be eliminated or when the substance leads to a case of organ dysfunction, such as in renal or hepatic failure. The causative substances cover a wide range, from medical drugs or agrichemicals to natural poisons (such as poisonous mushrooms). In removing these substances, gastric lavage, activated carbon administration, laxative administration or enema cleaning are the preferred methods, and blood purification is not routinely conducted. However, when the causative substance is unknown or when there are several causative substances, it is not easy to immediately grasp the disposition of the patient and so judge whether or not blood purification should be performed. In such cases, blood purification must be conducted in a timely manner and in accordance with the crisis management principle of 'prepare for the worst'. In general, substances whose molecular weight is within the removal spectrum, having a small distribution volume and a low protein-binding rate, are easier to remove. For substances with high protein-binding rates, albumin dialysis (MARS and Prometheus) is performed in order to remove albumin-binding substances. Since MARS and Prometheus have not been introduced in Japan, plasma diafiltration, employing selective plasma filtration with dialysis, is a practical alternative.

  20. Bacterial inclusion body purification.

    PubMed

    Seras-Franzoso, Joaquin; Peternel, Spela; Cano-Garrido, Olivia; Villaverde, Antonio; García-Fruitós, Elena

    2015-01-01

    Purification of bacterial inclusion bodies (IBs) is gaining importance due to the raising of novel applications for this type of submicron particulate protein clusters, with potential uses in the biomedical field among others. Here, we present two optimized methods to purify IBs adapting classical procedures to the material nature as well as the requirements of its final application.

  1. Diesel exhaust-gas purification system

    SciTech Connect

    Doherty, B.J.

    1982-07-01

    The design of a diesel exhaust gas purification system is presented. It will provide 2000 scfm of dry, anerobic gas (essentially nitrogen) for use in air drilling operations where drill pipe corrosion is a problem, such as geothermal applications. The system is operable in the field and may be transported via highways. It will operate at ambient temperatures up to 110/sup 0/F and requires no water - diesel fuel is used to combust excess oxygen and to generate electricity for the system. Gas production costs, including capital amortization, operations, fuel and maintenance (for reasonable utilization) are about $1.50/1000 scf.

  2. Water Purification Systems

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A water purification/recycling system developed by Photo-Catalytics, Inc. (PCI) for NASA is commercially available. The system cleanses and recycles water, using a "photo-catalysis" process in which light or radiant energy sparks a chemical reaction. Chemically stable semiconductor powders are added to organically polluted water. The powder absorbs ultraviolet light, and pollutants are oxidized and converted to carbon dioxide. Potential markets for the system include research and pharmaceutical manufacturing applications, as well as microchip manufacture and wastewater cleansing.

  3. Probabilistic theories with purification

    SciTech Connect

    Chiribella, Giulio; D'Ariano, Giacomo Mauro; Perinotti, Paolo

    2010-06-15

    We investigate general probabilistic theories in which every mixed state has a purification, unique up to reversible channels on the purifying system. We show that the purification principle is equivalent to the existence of a reversible realization of every physical process, that is, to the fact that every physical process can be regarded as arising from a reversible interaction of the system with an environment, which is eventually discarded. From the purification principle we also construct an isomorphism between transformations and bipartite states that possesses all structural properties of the Choi-Jamiolkowski isomorphism in quantum theory. Such an isomorphism allows one to prove most of the basic features of quantum theory, like, e.g., existence of pure bipartite states giving perfect correlations in independent experiments, no information without disturbance, no joint discrimination of all pure states, no cloning, teleportation, no programming, no bit commitment, complementarity between correctable channels and deletion channels, characterization of entanglement-breaking channels as measure-and-prepare channels, and others, without resorting to the mathematical framework of Hilbert spaces.

  4. Californium purification and electrodeposition

    DOE PAGES

    Burns, Jonathan D.; Van Cleve, Shelley M.; Smith, Edward Hamilton; ...

    2014-11-30

    The staff at the Radiochemical Engineering Development Center, located at Oak Ridge National Laboratory, produced a 6.3 ± 0.4 GBq (1.7 ± 0.1 Ci) 252Cf source for the Californium Rare Isotope Breeder Upgrade (CARIBU) project at Argonne National Laboratory’s Argonne Tandem Linac Accelerator System. The source was produced by electrodeposition of a 252Cf sample onto a stainless steel substrate, which required material free from excess mass for efficient deposition. The resulting deposition was the largest reported 252Cf electrodeposition source ever produced. Several different chromatographic purification methods were investigated to determine which would be most effective for final purification of themore » feed material used for the CARIBU source. The separation of lanthanides from the Cf was of special concern. Furthermore, the separation, using 145Sm, 153Gd, and 249Cf as tracers, was investigated using BioRad AG 50X8 in α-hydroxyisobutyric acid, Eichrom LN resin in both HNO3 and HCl, and Eichrom TEVA resin in NH4SCN. The TEVA NH4SCN system was found to completely separate 145Sm and 153Gd from 249Cf and was adopted into the purification process used in purifying the 252Cf.« less

  5. Californium purification and electrodeposition

    SciTech Connect

    Burns, Jonathan D.; Van Cleve, Shelley M.; Smith, Edward Hamilton; Boll, Rose Ann

    2014-11-30

    The staff at the Radiochemical Engineering Development Center, located at Oak Ridge National Laboratory, produced a 6.3 ± 0.4 GBq (1.7 ± 0.1 Ci) 252Cf source for the Californium Rare Isotope Breeder Upgrade (CARIBU) project at Argonne National Laboratory’s Argonne Tandem Linac Accelerator System. The source was produced by electrodeposition of a 252Cf sample onto a stainless steel substrate, which required material free from excess mass for efficient deposition. The resulting deposition was the largest reported 252Cf electrodeposition source ever produced. Several different chromatographic purification methods were investigated to determine which would be most effective for final purification of the feed material used for the CARIBU source. The separation of lanthanides from the Cf was of special concern. Furthermore, the separation, using 145Sm, 153Gd, and 249Cf as tracers, was investigated using BioRad AG 50X8 in α-hydroxyisobutyric acid, Eichrom LN resin in both HNO3 and HCl, and Eichrom TEVA resin in NH4SCN. The TEVA NH4SCN system was found to completely separate 145Sm and 153Gd from 249Cf and was adopted into the purification process used in purifying the 252Cf.

  6. Process for purification of silicon

    NASA Technical Reports Server (NTRS)

    Rath, H. J.; Sirtl, E.; Pfeiffer, W.

    1981-01-01

    The purification of metallurgically pure silicon having a silicon content of more than 95% by weight is accomplished by leaching with an acidic solution which substantially does not attack silicon. A mechanical treatment leading to continuous particle size reduction of the granulated silicon to be purified is combined with the chemical purification step.

  7. Oxygen Sag and Stream Purification.

    ERIC Educational Resources Information Center

    Neal, Larry; Herwig, Roy

    1978-01-01

    Presents a literature review of water quality related to oxygen sag and stream purification, covering publications of 1976-77. This review includes: (1) self-purification models; (2) oxygen demand; and (3) reaeration and oxygen transfer. A list of 60 references is also presented. (HM)

  8. Oxygen Sag and Stream Purification.

    ERIC Educational Resources Information Center

    Neal, Larry; Herwig, Roy

    1978-01-01

    Presents a literature review of water quality related to oxygen sag and stream purification, covering publications of 1976-77. This review includes: (1) self-purification models; (2) oxygen demand; and (3) reaeration and oxygen transfer. A list of 60 references is also presented. (HM)

  9. Purification of Clostridium toxoids.

    PubMed

    Buchowicz, I; Hay, M; Schiller, B; Korbecki, M; Sochańska, R

    1977-01-01

    A two-step fractionation procedure was applied for purification and concentration of the individual Clostridium toxoids. The toxoids were precipitated with hydrochloric acid in the presence of sodium sextametaphosphate, then antigenic fractions were separated from inactive contaminants by Sephadex G-75 filtration. Specific activity of the preparations thus obtained, as determined by Mancini radial immunodiffusion, was 150--565 binding units per mg of protein nitrogen for Clostridium perfringens toxoid, 204--352 binding units for Clostridium oedematiens toxoid and 26.6 -- 51.2 binding units for Clostridium septicum toxoid.

  10. Water Purification Product

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Ecomaster, an affiliate of BioServe Space Technologies, this PentaPure technology has been used to purify water for our nation's Space Shuttle missions since 1981. WTC-Ecomaster of Mirneapolis, Minnesota manufactures water purification systems under the brand name PentaPure (TM). BioServe researcher Dr. George Marchin, of Kansas State University, first demonstrated the superiority of this technology and licensed it to WTC. Marchin continues to perform microgravity research in the development of new technologies for the benefit of life on Earth.

  11. Water Purification Product

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Ecomaster, an affiliate of BioServe Space Technologies, this PentaPure technology has been used to purify water for our nation's Space Shuttle missions since 1981. WTC-Ecomaster of Mirneapolis, Minnesota manufactures water purification systems under the brand name PentaPure (TM). BioServe researcher Dr. George Marchin, of Kansas State University, first demonstrated the superiority of this technology and licensed it to WTC. Marchin continues to perform microgravity research in the development of new technologies for the benefit of life on Earth.

  12. Highly efficient Bell state purification and GHZ preparation and purification

    NASA Astrophysics Data System (ADS)

    Krastanov, Stefan; Jiang, Liang

    2016-05-01

    We investigate novel protocols for entanglement purification with Bell states. Employing genetic algorithms for the design of the purification circuit, we obtain shorter circuits giving higher success rates and better final fidelities than what is available in the literature. We generalize these circuits in order to prepare GHZ states from Bell pairs and to subsequently purify these GHZ states. We provide new threshold estimates for codes using these GHZ states for fault-tolerant stabilizer measurements.

  13. URANIUM PURIFICATION PROCESS

    DOEpatents

    Ruhoff, J.R.; Winters, C.E.

    1957-11-12

    A process is described for the purification of uranyl nitrate by an extraction process. A solution is formed consisting of uranyl nitrate, together with the associated impurities arising from the HNO/sub 3/ leaching of the ore, in an organic solvent such as ether. If this were back extracted with water to remove the impurities, large quantities of uranyl nitrate will also be extracted and lost. To prevent this, the impure organic solution is extracted with small amounts of saturated aqueous solutions of uranyl nitrate thereby effectively accomplishing the removal of impurities while not allowing any further extraction of the uranyl nitrate from the organic solvent. After the impurities have been removed, the uranium values are extracted with large quantities of water.

  14. Recovery and purification of ethylene

    DOEpatents

    Reyneke, Rian; Foral, Michael J.; Lee, Guang-Chung; Eng, Wayne W. Y.; Sinclair, Iain; Lodgson, Jeffery S.

    2008-10-21

    A process for the recovery and purification of ethylene and optionally propylene from a stream containing lighter and heavier components that employs an ethylene distributor column and a partially thermally coupled distributed distillation system.

  15. Simple and efficient purification of single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Dettlaff-Weglikowska, U.; Roth, S.

    2001-11-01

    Single-walled carbon nanotubes (SWNTs) produced by arc-discharge and laser ablation were purified by selective oxidation in air at 350°C and subsequent HCl treatment at 120°C. Raw soot and purified samples were analyzed with X-ray diffraction, thermogravimetric analysis (TGA), chemical analysis and transmission electron microscopy (TEM). The optimized purification temperature of SWNTs in air, 350°C, has been determined from TGA curves. Repetition of the oxidation and acid treatment, larger than 95 wt.% purity of SWNTs has been obtained.

  16. [Biocenotic dynamics of liquid sewage in the process of its biological purification at aeration stations].

    PubMed

    Kalina, G P; Vinogradova, L A; Gipp, E K

    1975-08-01

    A study was made of biological purification of sewage at the aeration stations on the quantitative composition of the main indicator microbes--of bacteria of the coliform group and of the fecal coliform bacilli, enterococci, Proteus, and also pathogenic enterobacteria. There was found a difference in the behaviour of different species of Proteus, i.e. reduction in the process of purification in the numbers of Pr. mirabilis, and a sharp elevation of Pr. morganii content. There was noted an insignificant amount of Pr. vulgaris both before and after the biological purification. It was found that dynamics of biocenosis was influenced by air temperature at the time of collection of the samples. A possibility of reproduction of coliform bacilli serving as one of the factors of autopurification of sewage during the biological purification was confirmed.

  17. Water Purification Systems

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Clearwater Pool Technologies employs NASA-developed silver/copper ionization to purify turtle and dolphin tanks, cooling towers, spas, water recycling systems, etc. The pool purifier consists of a microcomputer to monitor water conditions, a pair of metallic electrodes, and a rheostat controller. Ions are generated by passing a low voltage current through the electrodes; the silver ions kill the bacteria, and the copper ions kill algae. This technology has found broad application because it offers an alternative to chemical disinfectants. It was originally developed to purify water on Apollo spacecraft. Caribbean Clear has been using NASA's silver ionization technology for water purification for more than a decade. Two new products incorporate advancements of the basic technology. One is the AquaKing, a system designed for areas with no source of acceptable drinking water. Another is the Caribbean Clear Controller, designed for commercial pool and water park applications where sanitizing is combined with feedback control of pH and an oxidizer, chlorine or bromine. The technology was originally developed to purify water on Apollo spacecraft.

  18. Toll-Booth Purification

    NASA Technical Reports Server (NTRS)

    1977-01-01

    NASA's Technology Application Team at Stanford Research Institute searched available information and suggested a transfer of clean-room technology employing the use of the same laminar flow techniques found in environmental control systems of clean rooms used for contamination-free assembly of precision aerospace equipment. That information, from technology originally developed by NASA and the Energy Research & Development Administration was incorporated in the design of a prototype toll booth purifier. The draft-free design includes a "diffusor", which blows clean air out the toll booth doorway, thus retarding the infiltration of contaminated air. The net effect is a decrease in the toll collector's inhalation of exhaust fumes. The Washington Department of Highways installed the prototype system in a toll booth at the Evergreen Point Bridge near Seattle. After a successful two-year test, the department now has equipped all 10 of the bridge's toll booths with the air purifiers.

  19. Rapid purification of recombinant histones.

    PubMed

    Klinker, Henrike; Haas, Caroline; Harrer, Nadine; Becker, Peter B; Mueller-Planitz, Felix

    2014-01-01

    The development of methods to assemble nucleosomes from recombinant histones decades ago has transformed chromatin research. Nevertheless, nucleosome reconstitution remains time consuming to this day, not least because the four individual histones must be purified first. Here, we present a streamlined purification protocol of recombinant histones from bacteria. We termed this method "rapid histone purification" (RHP) as it circumvents isolation of inclusion bodies and thereby cuts out the most time-consuming step of traditional purification protocols. Instead of inclusion body isolation, whole cell extracts are prepared under strongly denaturing conditions that directly solubilize inclusion bodies. By ion exchange chromatography, the histones are purified from the extracts. The protocol has been successfully applied to all four canonical Drosophila and human histones. RHP histones and histones that were purified from isolated inclusion bodies had similar purities. The different purification strategies also did not impact the quality of octamers reconstituted from these histones. We expect that the RHP protocol can be readily applied to the purification of canonical histones from other species as well as the numerous histone variants.

  20. Exhaust purification with on-board ammonia production

    DOEpatents

    Robel, Wade J.; Driscoll, James J.; Coleman, Gerald N.; Knox, Kevin J.

    2009-06-30

    A power source is provided for use with selective catalytic reduction systems for exhaust-gas purification. The power source includes a first cylinder group with a first air-intake passage and a first exhaust passage, and a second cylinder group with a second air-intake passage and a second exhaust passage. The second air-intake passage is fluidly isolated from the first air-intake passage. A fuel-supply device may be configured to supply fuel into the first exhaust passage, and a catalyst may be disposed downstream of the fuel-supply device to convert at least a portion of the exhaust stream in the first exhaust passage into ammonia.

  1. Entanglement purification with double selection

    SciTech Connect

    Fujii, Keisuke; Yamamoto, Katsuji

    2009-10-15

    We investigate an entanglement purification protocol with double-selection process, which works under imperfect local operations. Compared with the usual protocol with single selection, this double-selection method has higher noise thresholds for the local operations and quantum communication channels and achieves higher fidelity of purified states. It also provides a yield comparable to that of the usual protocol with single selection. We discuss on general grounds how some of the errors which are introduced by local operations are left as intrinsically undetectable. The undetectable errors place a general upper bound on the purification fidelity. The double selection is a simple method to remove all the detectable errors in the first order, so that the upper bound on the fidelity is achieved in the low-noise regime. The double selection is further applied to purification of multipartite entanglement such as two-colorable graph states.

  2. Blood purification therapy for sepsis.

    PubMed

    Sakata, Hiromi; Yonekawa, Motoki; Kawamura, Akio

    2006-12-01

    Accumulating evidences of underlining pathogenesis of sepsis have contributed to the therapeutic strategy for sepsis. Not only endotoxin and cytokine, but also signal transduction through Toll-like receptors could be a strategic target for the management of sepsis. Blood purification therapy including polymyxin B-immobilized hemoperfusion cartridge and continuous hemodiafiltration has shown the beneficial effect on patients with sepsis in Japan. Although they were initially designed to remove endotoxin and cytokines respectively, they might eliminate unexpected mediators responsible for sepsis. Further elucidation of mechanism and randomized controlled studies are needed to establish the role of blood purification therapy in sepsis.

  3. Purification of 70S ribosomes.

    PubMed

    Rivera, Maria C; Maguire, Bruce; Lake, James A

    2015-03-02

    Here we describe the further purification of prokaryotic ribosomal particles obtained after the centrifugation of a crude cell lysate through a sucrose cushion. In this final purification step, a fraction containing ribosomes, ribosomal subunits, and polysomes is centrifuged through a 7%-30% (w/w) linear sucrose gradient to isolate tight couple 70S ribosomes, as well as dissociated 30S and 50S subunits. The tight couples fraction, or translationally active ribosome fraction, is composed of intact vacant ribosomes that can be used in cell-free translation systems.

  4. An overview of lectins purification strategies.

    PubMed

    Nascimento, Kelany S; Cunha, Ana I; Nascimento, Kyria S; Cavada, Benildo S; Azevedo, Ana M; Aires-Barros, Maria Raquel

    2012-11-01

    Lectins hold great promise not only as reagents for diagnostics and drug discovery but also as a novel class of biopharmaceutical products. In fact, new research directions in the last years have led to major developments in the uses of plant lectins as therapeutic agents against numerous diseases in an ageing society. It is even expected that lectins may occupy an important place in the biopharmaceutical industry next to monoclonal antibodies. All these new trends are placing a tremendous emphasis on the development of new approaches for faster lectins development, selection, and optimization, including alternatives methods of purification. This article reviews the isolation and purification methods used for lectins purification. Origins and applications of lectins are described, highlighting the special features of this class of proteins, such as the carbohydrated-binding domains and their importance in the development of affinity methodologies to increase and facilitate lectins purification. Published strategies for the purification of lectins from different sources are analyzed in relation to the purification methods used, their sequence, and the number of times they are used in a purification procedure. The purity of lectins is analyzed in relation to the average overall yield and purification factors obtained for each purification scheme for these proteins and the purification steps necessary. New directions are described for improving lectins separation and purification. Copyright © 2012 John Wiley & Sons, Ltd.

  5. [Immobilized microorganisms and water purification].

    PubMed

    Mogilevich, N F

    1995-01-01

    Advantages and disadvantages of cells of aerobic microorganisms immobilized by the type of adhesion and incorporation into the gel beads, the amount of retained biomass, limitations of diffusion of oxygen and nutrients, viability, morphology, biochemical properties are described. Immobilized biocatalysts are discussed in the aspect of their use in purification of sewage waters.

  6. Entanglement purification for quantum communication.

    PubMed

    Pan, J W; Simon, C; Brukner, C; Zeilinger, A

    2001-04-26

    The distribution of entangled states between distant locations will be essential for the future large-scale realization of quantum communication schemes such as quantum cryptography and quantum teleportation. Because of unavoidable noise in the quantum communication channel, the entanglement between two particles is more and more degraded the further they propagate. Entanglement purification is thus essential to distil highly entangled states from less entangled ones. Existing general purification protocols are based on the quantum controlled-NOT (CNOT) or similar quantum logic operations, which are very difficult to implement experimentally. Present realizations of CNOT gates are much too imperfect to be useful for long-distance quantum communication. Here we present a scheme for the entanglement purification of general mixed entangled states, which achieves 50 per cent of the success probability of schemes based on the CNOT operation, but requires only simple linear optical elements. Because the perfection of such elements is very high, the local operations necessary for purification can be performed with the required precision. Our procedure is within the reach of current technology, and should significantly simplify the implementation of long-distance quantum communication.

  7. Rapid Purification of Recombinant Histones

    PubMed Central

    Klinker, Henrike; Becker, Peter B.; Mueller-Planitz, Felix

    2014-01-01

    The development of methods to assemble nucleosomes from recombinant histones decades ago has transformed chromatin research. Nevertheless, nucleosome reconstitution remains time consuming to this day, not least because the four individual histones must be purified first. Here, we present a streamlined purification protocol of recombinant histones from bacteria. We termed this method “rapid histone purification” (RHP) as it circumvents isolation of inclusion bodies and thereby cuts out the most time-consuming step of traditional purification protocols. Instead of inclusion body isolation, whole cell extracts are prepared under strongly denaturing conditions that directly solubilize inclusion bodies. By ion exchange chromatography, the histones are purified from the extracts. The protocol has been successfully applied to all four canonical Drosophila and human histones. RHP histones and histones that were purified from isolated inclusion bodies had similar purities. The different purification strategies also did not impact the quality of octamers reconstituted from these histones. We expect that the RHP protocol can be readily applied to the purification of canonical histones from other species as well as the numerous histone variants. PMID:25090252

  8. Biobased monoliths for adenovirus purification.

    PubMed

    Fernandes, Cláudia S M; Gonçalves, Bianca; Sousa, Margarida; Martins, Duarte L; Barroso, Telma; Pina, Ana Sofia; Peixoto, Cristina; Aguiar-Ricardo, Ana; Roque, A Cecília A

    2015-04-01

    Adenoviruses are important platforms for vaccine development and vectors for gene therapy, increasing the demand for high titers of purified viral preparations. Monoliths are macroporous supports regarded as ideal for the purification of macromolecular complexes, including viral particles. Although common monoliths are based on synthetic polymers as methacrylates, we explored the potential of biopolymers processed by clean technologies to produce monoliths for adenovirus purification. Such an approach enables the development of disposable and biodegradable matrices for bioprocessing. A total of 20 monoliths were produced from different biopolymers (chitosan, agarose, and dextran), employing two distinct temperatures during the freezing process (-20 °C and -80 °C). The morphological and physical properties of the structures were thoroughly characterized. The monoliths presenting higher robustness and permeability rates were further analyzed for the nonspecific binding of Adenovirus serotype 5 (Ad5) preparations. The matrices presenting lower nonspecific Ad5 binding were further functionalized with quaternary amine anion-exchange ligand glycidyltrimethylammonium chloride hydrochloride by two distinct methods, and their performance toward Ad5 purification was assessed. The monolith composed of chitosan and poly(vinyl) alcohol (50:50) prepared at -80 °C allowed 100% recovery of Ad5 particles bound to the support. This is the first report of the successful purification of adenovirus using monoliths obtained from biopolymers processed by clean technologies.

  9. Bioinspired Materials for Water Purification.

    PubMed

    Gonzalez-Perez, Alfredo; Persson, Kenneth M

    2016-06-03

    Water scarcity issues associated with inadequate access to clean water and sanitation is a ubiquitous problem occurring globally. Addressing future challenges will require a combination of new technological development in water purification and environmental remediation technology with suitable conservation policies. In this scenario, new bioinspired materials will play a pivotal role in the development of more efficient and environmentally friendly solutions. The role of amphiphilic self-assembly on the fabrication of new biomimetic membranes for membrane separation like reverse osmosis is emphasized. Mesoporous support materials for semiconductor growth in the photocatalytic degradation of pollutants and new carriers for immobilization of bacteria in bioreactors are used in the removal and processing of different kind of water pollutants like heavy metals. Obstacles to improve and optimize the fabrication as well as a better understanding of their performance in small-scale and pilot purification systems need to be addressed. However, it is expected that these new biomimetic materials will find their way into the current water purification technologies to improve their purification/removal performance in a cost-effective and environmentally friendly way.

  10. Purification and concentration of alphavirus.

    PubMed

    Lundstrom, Kenneth

    2012-07-01

    The alphaviruses Semliki Forest virus and Sindbis virus have been used frequently as expression vectors in vitro and in vivo. Usually, these systems consist of replication-deficient vectors that require a helper vector for packaging of recombinant particles. Replication-proficient vectors have also been engineered. Alphaviral vectors can be used as nucleic-acid-based vectors (DNA and RNA) or infectious particles. High-titer viral production is achieved in <2 d. The broad host range of alphaviruses facilitates studies in mammalian and nonmammalian cell lines, primary cells in culture, and in vivo. The strong preference for expression in neuronal cells has made alphaviruses particularly useful in neurobiological studies. Unfortunately, their strong cytotoxic effect on host cells, relatively short-term transient expression patterns, and the reasonably high cost of viral production remain drawbacks. However, novel mutant alphaviruses have showed reduced cytotoxicity and prolonged expression. Membrane proteins (which are generally difficult to express at high levels in recombinant systems) have generated high yields and facilitate applications in structural biology. Alphaviruses have also been applied in vaccine development and gene therapy. Generally, purification or concentration of alphaviruses is not necessary. However, for instance, the medium derived from baby hamster kidney cells is toxic to primary neurons in culture. Including a purification step substantially improves the survival of the transduced neurons. Viral concentration and purification may also be advantageous for in vivo studies in animal models and are mandatory for clinical applications. This protocol describes three methods for purification and concentration of alphavirus.

  11. Regenerable Incinerator Exhaust Purification and Trace Contaminant Control System

    NASA Technical Reports Server (NTRS)

    Finn, John E.; Cho, Shelia Y.; LeVan, M. Douglas

    2003-01-01

    In this novel approach to air purification, contaminants removed from a process air stream by a high-capacity adsorbent are displaced periodically by a warm, high-humidity, reverse-flow air stream. Displaced contaminants flow into a closed regeneration loop, in which organic compounds are oxidized catalytically and acid gases are removed by a gas- water contactor (which also serves as the source of the water vapor). These features are expected to result in a design that has few expendables and lower energy consumption than alternative regenerable techniques. The joint project between NASA Ames Research Center and Vanderbilt University has completed its third year. Breadboard development continues at NASA Ames, while Vanderbilt has completed most of its adsorption equilibria development. Vanderbilt has completed its fixed-bed apparatus for investigation of dynamic adsorption and desorption processes for trace organic compounds and water vapor, and is continuing its development of the mathematical model describing the column dynamics.

  12. Radon assay and purification techniques

    SciTech Connect

    Simgen, Hardy

    2013-08-08

    Radon is a source of background in many astroparticle physics experiments searching for rare low energy events. In this paper an overview about radon in the field is given including radon detection techniques, radon sources and material screening with respect to radon emanation. Finally, also the problem of long-lived radioactive {sup 222}Rn-daughters and the question of gas purification from radon is addressed.

  13. Water purification using organic salts

    DOEpatents

    Currier, Robert P.

    2004-11-23

    Water purification using organic salts. Feed water is mixed with at least one organic salt at a temperature sufficiently low to form organic salt hydrate crystals and brine. The crystals are separated from the brine, rinsed, and melted to form an aqueous solution of organic salt. Some of the water is removed from the aqueous organic salt solution. The purified water is collected, and the remaining more concentrated aqueous organic salt solution is reused.

  14. Purification of Tetrahymena cytoskeletal proteins.

    PubMed

    Honts, Jerry E

    2012-01-01

    Like all eukaryotic cells, Tetrahymena thermophila contains a rich array of cytoskeletal proteins, some familiar and some novel. A detailed analysis of the structure, function, and interactions of these proteins requires procedures for purifying the individual protein components. Procedures for the purification of actin and tubulin from Tetrahymena are reviewed, followed by a description of a procedure that yields proteins from the epiplasmic layer and associated structures, including the tetrins. Finally, the challenges and opportunities for future advances are assessed.

  15. Melting And Purification Of Niobium

    NASA Astrophysics Data System (ADS)

    Moura, Hernane R. Salles; de Moura, Lourenço

    2007-08-01

    The aspects involved in the purification of niobium in Electron Beam Furnaces will be outlined and correlated with practical experience accumulated over 17 years of continuously producing high purity niobium metal and niobium-zirconium ingots at CBMM, meeting the needs for a wide range of uses. This paper also reports some comments regarding raw material requirements, the experience on cold hearth operation melting niobium and the production of large grains niobium ingots by CBMM with some comments of their main characteristics.

  16. Melting And Purification Of Niobium

    SciTech Connect

    Salles Moura, Hernane R.; Moura, Lourenco de

    2007-08-09

    The aspects involved in the purification of niobium in Electron Beam Furnaces will be outlined and correlated with practical experience accumulated over 17 years of continuously producing high purity niobium metal and niobium-zirconium ingots at CBMM, meeting the needs for a wide range of uses. This paper also reports some comments regarding raw material requirements, the experience on cold hearth operation melting niobium and the production of large grains niobium ingots by CBMM with some comments of their main characteristics.

  17. Technological assumptions for biogas purification.

    PubMed

    Makareviciene, Violeta; Sendzikiene, Egle

    2015-01-01

    Biogas can be used in the engines of transport vehicles and blended into natural gas networks, but it also requires the removal of carbon dioxide, hydrogen sulphide, and moisture. Biogas purification process flow diagrams have been developed for a process enabling the use of a dolomite suspension, as well as for solutions obtained by the filtration of the suspension, to obtain biogas free of hydrogen sulphide and with a carbon dioxide content that does not exceed 2%. The cost of biogas purification was evaluated on the basis of data on biogas production capacity and biogas production cost obtained from local water treatment facilities. It has been found that, with the use of dolomite suspension, the cost of biogas purification is approximately six times lower than that in the case of using a chemical sorbent such as monoethanolamine. The results showed travelling costs using biogas purified by dolomite suspension are nearly 1.5 time lower than travelling costs using gasoline and slightly lower than travelling costs using mineral diesel fuel.

  18. SNO+ Scintillator Purification and Assay

    NASA Astrophysics Data System (ADS)

    Ford, R.; Chen, M.; Chkvorets, O.; Hallman, D.; Vázquez-Jáuregui, E.

    2011-04-01

    We describe the R&D on the scintillator purification and assay methods and technology for the SNO+ neutrino and double-beta decay experiment. The SNO+ experiment is a replacement of the SNO heavy water with liquid scintillator comprised of 2 g/L PPO in linear alkylbenzene (LAB). During filling the LAB will be transported underground by rail car and purified by multi-stage distillation and steam stripping at a flow rate of 19 LPM. While the detector is operational the scintillator can be recirculated at 150 LPM (full detector volume in 4 days) to provide repurification as necessary by either water extraction (for Ra, K, Bi) or by functional metal scavenger columns (for Pb, Ra, Bi, Ac, Th) followed by steam stripping to remove noble gases and oxygen (Rn, O2, Kr, Ar). The metal scavenger columns also provide a method for scintillator assay for ex-situ measurement of the U and Th chain radioactivity. We have developed "natural" radioactive spikes of Pb and Ra in LAB and use these for purification testing. Lastly, we present the planned operating modes and purification strategies and the plant specifications and design.

  19. SNO+ Scintillator Purification and Assay

    SciTech Connect

    Ford, R.; Vazquez-Jauregui, E.; Chen, M.; Chkvorets, O.; Hallman, D.

    2011-04-27

    We describe the R and D on the scintillator purification and assay methods and technology for the SNO+ neutrino and double-beta decay experiment. The SNO+ experiment is a replacement of the SNO heavy water with liquid scintillator comprised of 2 g/L PPO in linear alkylbenzene (LAB). During filling the LAB will be transported underground by rail car and purified by multi-stage distillation and steam stripping at a flow rate of 19 LPM. While the detector is operational the scintillator can be recirculated at 150 LPM (full detector volume in 4 days) to provide repurification as necessary by either water extraction (for Ra, K, Bi) or by functional metal scavenger columns (for Pb, Ra, Bi, Ac, Th) followed by steam stripping to remove noble gases and oxygen (Rn, O{sub 2}, Kr, Ar). The metal scavenger columns also provide a method for scintillator assay for ex-situ measurement of the U and Th chain radioactivity. We have developed ''natural'' radioactive spikes of Pb and Ra in LAB and use these for purification testing. Lastly, we present the planned operating modes and purification strategies and the plant specifications and design.

  20. Synergistic effect of Brønsted acid and platinum on purification of automobile exhaust gases

    PubMed Central

    Fu, Wei; Li, Xin-Hao; Bao, Hong-Liang; Wang, Kai-Xue; Wei, Xiao; Cai, Yi-Yu; Chen, Jie-Sheng

    2013-01-01

    The catalytic purification of automobile exhaust gases (CO, NOx and hydrocarbons) is one of the most practiced conversion processes used to lower the emissions and to reduce the air pollution. Nevertheless, the good performance of exhaust gas purification catalysts often requires the high consumption of noble metals such as platinum. Here we report that the Brønsted acid sites on the external surface of a microporous silicoaluminophosphate (SAPO) act as a promoter for exhaust gas purification, effectively cutting the loading amount of platinum in the catalyst without sacrifice of performance. It is revealed that in the Pt-loaded SAPO-CHA catalyst, there exists a remarkable synergistic effect between the Brønsted acid sites and the Pt nanoparticles, the former helping to adsorb and activate the hydrocarbon molecules for NO reduction during the catalytic process. The thermal stability of SAPO-CHA also makes the composite catalyst stable and reusable without activity decay. PMID:23907148

  1. Synergistic effect of Brønsted acid and platinum on purification of automobile exhaust gases.

    PubMed

    Fu, Wei; Li, Xin-Hao; Bao, Hong-Liang; Wang, Kai-Xue; Wei, Xiao; Cai, Yi-Yu; Chen, Jie-Sheng

    2013-01-01

    The catalytic purification of automobile exhaust gases (CO, NOx and hydrocarbons) is one of the most practiced conversion processes used to lower the emissions and to reduce the air pollution. Nevertheless, the good performance of exhaust gas purification catalysts often requires the high consumption of noble metals such as platinum. Here we report that the Brønsted acid sites on the external surface of a microporous silicoaluminophosphate (SAPO) act as a promoter for exhaust gas purification, effectively cutting the loading amount of platinum in the catalyst without sacrifice of performance. It is revealed that in the Pt-loaded SAPO-CHA catalyst, there exists a remarkable synergistic effect between the Brønsted acid sites and the Pt nanoparticles, the former helping to adsorb and activate the hydrocarbon molecules for NO reduction during the catalytic process. The thermal stability of SAPO-CHA also makes the composite catalyst stable and reusable without activity decay.

  2. Synergistic effect of Brønsted acid and platinum on purification of automobile exhaust gases

    NASA Astrophysics Data System (ADS)

    Fu, Wei; Li, Xin-Hao; Bao, Hong-Liang; Wang, Kai-Xue; Wei, Xiao; Cai, Yi-Yu; Chen, Jie-Sheng

    2013-08-01

    The catalytic purification of automobile exhaust gases (CO, NOx and hydrocarbons) is one of the most practiced conversion processes used to lower the emissions and to reduce the air pollution. Nevertheless, the good performance of exhaust gas purification catalysts often requires the high consumption of noble metals such as platinum. Here we report that the Brønsted acid sites on the external surface of a microporous silicoaluminophosphate (SAPO) act as a promoter for exhaust gas purification, effectively cutting the loading amount of platinum in the catalyst without sacrifice of performance. It is revealed that in the Pt-loaded SAPO-CHA catalyst, there exists a remarkable synergistic effect between the Brønsted acid sites and the Pt nanoparticles, the former helping to adsorb and activate the hydrocarbon molecules for NO reduction during the catalytic process. The thermal stability of SAPO-CHA also makes the composite catalyst stable and reusable without activity decay.

  3. Argon Collection And Purification For Proliferation Detection

    SciTech Connect

    Achey, R.; Hunter, D.

    2015-10-09

    In order to determine whether a seismic event was a declared/undeclared underground nuclear weapon test, environmental samples must be taken and analyzed for signatures that are unique to a nuclear explosion. These signatures are either particles or gases. Particle samples are routinely taken and analyzed under the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) verification regime as well as by individual countries. Gas samples are analyzed for signature gases, especially radioactive xenon. Underground nuclear tests also produce radioactive argon, but that signature is not well monitored. A radioactive argon signature, along with other signatures, can more conclusively determine whether an event was a nuclear test. This project has developed capabilities for collecting and purifying argon samples for ultra-low-background proportional counting. SRNL has developed a continuous gas enrichment system that produces an output stream containing 97% argon from whole air using adsorbent separation technology (the flow diagram for the system is shown in the figure). The vacuum swing adsorption (VSA) enrichment system is easily scalable to produce ten liters or more of 97% argon within twelve hours. A gas chromatographic separation using a column of modified hydrogen mordenite molecular sieve has been developed that can further purify the sample to better than 99% purity after separation from the helium carrier gas. The combination of these concentration and purification systems has the capability of being used for a field-deployable system for collecting argon samples suitable for ultra-low-background proportional counting for detecting nuclear detonations under the On-Site Inspection program of the CTBTO verification regime. The technology also has applications for the bulk argon separation from air for industrial purposes such as the semi-conductor industry.

  4. Ion exchange purification of scandium

    DOEpatents

    Herchenroeder, L.A.; Burkholder, H.R.

    1990-10-23

    An improvement in purification of scandium through ion exchange chromatography is disclosed in which the oxidation potential of the eluting solution is altered by the addition of potassium chlorate or ammonium chloride so that removal of contaminants is encouraged. The temperature, pH and concentration of the eluent HEDTA are controlled in order to maintain the scandium in the column while minimizing dilution of the scandium band. Recovery of scandium is improved by pumping dilute scandium over the column prior to stripping the scandium and precipitation. This eliminates the HEDTA ion and other monovalent cations contaminating the scandium band. This method maximizes recovery of scandium while maintaining purity. 2 figs.

  5. Ion exchange purification of scandium

    DOEpatents

    Herchenroeder, Laurie A.; Burkholder, Harvey R.

    1990-10-23

    An improvement in purification of scandium through ion exchange chromatography is disclosed in which the oxidation potential of the eluting solution is altered by the addition of potassium chlorate or ammonium chloride so that removal of contaminants is encouraged. The temperature, pH and concentration of the eluent HEDTA are controlled in order to maintain the scandium in the column while minimizing dilution of the scandium band. Recovery of scandium is improved by pumping dilute scandium over the column prior to stripping the scandium and precipitation. This eliminates the HEDTA ion and other monovalent cations contaminating the scandium band. This method maximizes recovery of scandium while maintaining purity.

  6. Purification of noisy quantum measurements

    SciTech Connect

    Dall'Arno, Michele; D'Ariano, Giacomo Mauro; Sacchi, Massimiliano F.

    2010-10-15

    We consider the problem of improving noisy quantum measurements by suitable preprocessing strategies making many noisy detectors equivalent to a single ideal detector. For observables pertaining to finite-dimensional systems (e.g., qubits or spins) we consider preprocessing strategies that are reminiscent of quantum error correction procedures and allow one to perfectly measure an observable on a single quantum system for increasing number of inefficient detectors. For measurements of observables with an unbounded spectrum (e.g., photon number and homodyne and heterodyne detection), the purification of noisy quantum measurements can be achieved by preamplification as suggested by Yuen [Opt. Lett. 12, 789 (1987)].

  7. THE PURIFICATION OF HYPERTENSIN I

    PubMed Central

    Skeggs, Leonard T.; Marsh, Walton H.; Kahn, Joseph R.; Shumway, Norman P.

    1954-01-01

    The purification of hypertensin I has been described. The final product which is four times as powerful a pressor agent as l-arterenol, is obtained with an over-all recovery of 40 per cent. The product consists of a single component in countercurrent distribution, having a nitrogen content of 15.97 per cent and a specific activity of 7050 Goldblatt units per mg. of N or 1125 units per mg. of solid. Acid hydrolysis and paper chromatography indicate in a preliminary fashion that there are about nine amino acids present in the intact polypeptide. PMID:13201713

  8. Testing of chemically treated adsorbent air purifiers

    SciTech Connect

    Kelly, T.J. . Dept. of Atmospheric Science and Applied Technology); Kinkead, D.A. )

    1993-07-01

    New highly sensitive continuous monitors permit testing of air filters at parts-per-billion contaminant concentrations. This article describes testing of air purification filters intended for use in the National Archives 2 building in College Park, Maryland, using a test procedure that simulates the actual conditions of use. This test demonstrates both the effectiveness of the adsorbers at low contaminant levels, and the capability of existing instruments for conducting such tests. ASHRAE TC 2.3 (Gaseous Air Contaminants and Gas Contaminant Removal Equipment) is currently sponsoring research projects (follow-on studies to ASHRAE Project RP-674) aimed at developing a standard that will test and rate the performance of different types of gas phase air purification equipment at low concentrations. The work detailed in this article represents a first of this type of testing and a technical benchmark that may aid in the further development of ASHRAE gas phase performance standards.

  9. Purification & Characterization of Transcription Factors

    PubMed Central

    Nagore, LI; Nadeau, RJ; Guo, Q; Jadhav, YLA; Jarrett, HW; Haskins, WE

    2013-01-01

    Transcription factors (TFs) are essential for the expression of all proteins, including those involved in human health and disease. However, TFs are resistant to proteomic characterization because they are frequently masked by more abundant proteins due to the limited dynamic range of capillary liquid chromatography-tandem mass spectrometry and protein database searching. Purification methods, particularly strategies that exploit the high affinity of TFs for DNA response elements on gene promoters, can enrich TFs prior to proteomic analysis to improve dynamic range and penetrance of the TF proteome. For example, trapping of TF complexes specific for particular response elements has been achieved by recovering the element DNA-protein complex on solid supports. Additional methods for improving dynamic range include two- and three-dimensional gel electrophoresis incorporating electrophoretic mobility shift assays and Southwestern blotting for detection. Here we review methods for TF purification and characterization. We fully expect that future investigations will apply these and other methods to illuminate this important but challenging proteome. PMID:23832591

  10. Purification of aqueous cellulose ethers

    SciTech Connect

    Bartscherer, K.A.; de Pablo, J.J.; Bonnin, M.C.; Prausnitz, J.M.

    1990-07-01

    Manufacture of cellulose ethers usually involves high amounts of salt by-products. For application of the product, salt must be removed. In this work, we have studied the injection of high-pressure CO{sub 2} into an aqueous polymer-salt solution; we find that upon addition of isopropanol in addition to CO{sub 2}, the solution separates into two phases. One phase is rich in polymer and water, and the other phase contains mostly isopropanol, water and CO{sub 2}. The salt distributes between the two phases, thereby offering interesting possibilities for development of a new purification process for water-soluble polymers. This work presents experimental phase-equilibrium data for hydroxyethyl cellulose and sodium carboxymethyl cellulose with sodium acetate and potassium sulfate, respectively, in the region 40{degree}C and 30 to 80 bar. Based on these data, we suggest a process for the manufacture and purification of water-soluble cellulose ethers. 15 refs., 14 figs., 9 tabs.

  11. Semiconductor grade, solar silicon purification project

    NASA Technical Reports Server (NTRS)

    Ingle, W. M.; Rosler, R. R.; Thompson, S. W.; Chaney, R. E.

    1979-01-01

    Experimental apparatus and procedures used in the development of a 3-step SiF2(x) polymer transport purification process are described. Both S.S.M.S. and E.S. analysis demonstrated that major purification had occured and some samples were indistinguishable from semiconductor grade silicon (except possibly for phosphorus). Recent electrical analysis via crystal growth reveals that the product contains compensated phosphorus and boron. The low projected product cost and short energy payback time suggest that the economics of this process will result in a cost less than the goal of $10/Kg(1975 dollars). The process appears to be readily scalable to a major silicon purification facility.

  12. RHELP (Regenerative High Efficiency Low Pressure) Air Purification System

    DTIC Science & Technology

    2009-06-18

    200 DM M P  Ae ro so l C ol le ct ed  o n  Fi lte r ( g) DMMP Nebulized (g) 138 kPa nebulizer pr cm/s face velocity essure , 9.3  138 kPa nebulizer pr cm...s face velocity essure , 9.3  276 kPa nebulizer pr cm/s face velocity essure , 9.3  276 kPa nebulizer pr cm/s face velocity essure , 9.3  276 kPa...nebulizer pr cm/s face velocity essure , 5.6  Figure 55: DMMP Aerosol Collected on Filter as a Function of DMMP Nebulized with Both SiC Tubes and a Single

  13. Visible Light Responsive Catalyst for Air Water Purification Project

    NASA Technical Reports Server (NTRS)

    Wheeler, Raymond M.

    2014-01-01

    Investigate and develop viable approaches to render the normally UV-activated TIO2 catalyst visible light responsive (VLR) and achieve high and sustaining catalytic activity under the visible region of the solar spectrum.

  14. Biotemplated diatom silica-titania materials for air purification.

    PubMed

    Van Eynde, Erik; Tytgat, Tom; Smits, Marianne; Verbruggen, Sammy W; Hauchecorne, Birger; Lenaerts, Silvia

    2013-04-01

    We present a novel manufacture route for silica-titania photocatalysts using the diatom microalga Pinnularia sp. Diatoms self-assemble into porous silica cell walls, called frustules, with periodic micro-, meso- and macroscale features. This unique hierarchical porous structure of the diatom frustule is used as a biotemplate to incorporate titania by a sol-gel methodology. Important material characteristics of the modified diatom frustules under study are morphology, crystallinity, surface area, pore size and optical properties. The produced biosilica-titania material is evaluated towards photocatalytic activity for NOx abatement under UV radiation. This research is the first step to obtain sustainable, well-immobilised silica-titania photocatalysts using diatoms.

  15. EVALUATION OF AIR PURIFICATION DEVICES FOR CONTROL OF INDOOR PM

    EPA Science Inventory

    Because people spend most of their time indoors (89%), the indoor environment is a primary determinant of particle exposure. The indoor environment is especially an important determinant for the very young, the very old, and those with underlying cardiopulmonary disease because...

  16. EVALUATION OF AIR PURIFICATION DEVICES FOR CONTROL OF INDOOR PM

    EPA Science Inventory

    Because people spend most of their time indoors (89%), the indoor environment is a primary determinant of particle exposure. The indoor environment is especially an important determinant for the very young, the very old, and those with underlying cardiopulmonary disease because...

  17. Air Research

    EPA Pesticide Factsheets

    EPA's air research provides the critical science to develop and implement outdoor air regulations under the Clean Air Act and puts new tools and information in the hands of air quality managers and regulators to protect the air we breathe.

  18. Purification of lysozyme using ultrafiltration.

    PubMed

    Ghosh, R; Cui, Z F

    2000-04-20

    This article examines the separation of lysozyme from chicken egg white by ultrafiltration with 25 kDa and 50 kDa MWCO polysulfone membranes. The effects of pH, system hydrodynamics, feed concentration, and transmembrane pressure on permeate flux, lysozyme transmission, purification factor, and productivity have been discussed. With both types of membranes, higher permeate flux and lysozyme transmission were observed at higher pH. Higher lysozyme purity was generally obtained with the 25 kDa MWCO membrane. Purity of lysozyme decreased when the feed concentration was increased. With the 50 kDa MWCO membrane permeate flux, productivity and the purity of lysozyme were found to increase with increase in transmembrane pressure. The possibility of using a two-step ultrafiltration process for achieving high productivity along with high purity of lysozyme was also investigated.

  19. Reverse osmosis water purification system

    NASA Technical Reports Server (NTRS)

    Ahlstrom, H. G.; Hames, P. S.; Menninger, F. J.

    1986-01-01

    A reverse osmosis water purification system, which uses a programmable controller (PC) as the control system, was designed and built to maintain the cleanliness and level of water for various systems of a 64-m antenna. The installation operates with other equipment of the antenna at the Goldstone Deep Space Communication Complex. The reverse osmosis system was designed to be fully automatic; with the PC, many complex sequential and timed logic networks were easily implemented and are modified. The PC monitors water levels, pressures, flows, control panel requests, and set points on analog meters; with this information various processes are initiated, monitored, modified, halted, or eliminated as required by the equipment being supplied pure water.

  20. Gas purification by nonthermal plasma: a case study of ethylene.

    PubMed

    Aerts, R; Tu, X; Van Gaens, W; Whitehead, J C; Bogaerts, A

    2013-06-18

    The destruction of ethylene in a dielectric barrier discharge plasma is investigated by the combination of kinetic modeling and experiments, as a case study for plasma-based gas purification. The influence of the specific energy deposition on the removal efficiency and the selectivity toward CO and CO2 is studied for different concentrations of ethylene. The model allows the identification of the destruction pathway in dry and humid air. The latter is found to be mainly initiated by metastable N2 molecules, but the further destruction steps are dominated by O atoms and OH radicals. Upon increasing air humidity, the removal efficiency drops by ± 15% (from 85% to 70%), but the selectivity toward CO and CO2 stays more or less constant at 60% and 22%, respectively. Beside CO and CO2, we also identified acetylene, formaldehyde, and water as byproducts of the destruction process, with concentrations of 1606 ppm, 15033 ppm, and 185 ppm in humid air (with 20% RH), respectively. Finally, we investigated the byproducts generated by the humid air discharge itself, which are the greenhouse gases O3, N2O, and the toxic gas NO2.

  1. Liquid membrane purification of biogas

    SciTech Connect

    Majumdar, S.; Guha, A.K.; Lee, Y.T.; Papadopoulos, T.; Khare, S. . Dept. of Chemistry and Chemical Engineering)

    1991-03-01

    Conventional gas purification technologies are highly energy intensive. They are not suitable for economic removal of CO{sub 2} from methane obtained in biogas due to the small scale of gas production. Membrane separation techniques on the other hand are ideally suited for low gas production rate applications due to their modular nature. Although liquid membranes possess a high species permeability and selectivity, they have not been used for industrial applications due to the problems of membrane stability, membrane flooding and poor operational flexibility, etc. A new hollow-fiber-contained liquid membrane (HFCLM) technique has been developed recently. This technique overcomes the shortcomings of the traditional immobilized liquid membrane technology. A new technique uses two sets of hydrophobic, microporous hollow fine fibers, packed tightly in a permeator shell. The inter-fiber space is filled with an aqueous liquid acting as the membrane. The feed gas mixture is separated by selective permeation of a species through the liquid from one fiber set to the other. The second fiber set carries a sweep stream, gas or liquid, or simply the permeated gas stream. The objectives (which were met) of the present investigation were as follows. To study the selective removal of CO{sub 2} from a model biogas mixture containing 40% CO{sub 2} (the rest being N{sub 2} or CH{sub 4}) using a HFCLM permeator under various operating modes that include sweep gas, sweep liquid, vacuum and conventional permeation; to develop a mathematical model for each mode of operation; to build a large-scale purification loop and large-scale permeators for model biogas separation and to show stable performance over a period of one month.

  2. Purification of polymorphic components of complex genomes

    DOEpatents

    Stodolsky, M.

    1988-01-21

    A method for processing related subject and reference macromolecule composed of complementary strand into their respective subject and reference populations of representative fragments and effectuating purification of unique polymorphic subject fragments. 1 fig.

  3. Purification of polymorphic components of complex genomes

    DOEpatents

    Stodolsky, M.

    1991-07-16

    A method is disclosed for processing related subject and reference macromolecule populations composed of complementary strands into their respective subject and reference populations of representative fragments and effectuating purification of unique polymorphic subject fragments. 1 figure.

  4. Purification of basophils from peripheral human blood.

    PubMed

    Falcone, Franco H; Gibbs, Bernhard F

    2014-01-01

    The purification of basophils from peripheral blood has represented a formidable challenge for researchers since they were discovered by Paul Ehrlich in 1879. From the first published attempts in the late 1960s, it took half a century to develop robust protocols able to provide sufficient numbers of pure, functionally unimpaired basophils. The existing protocols for basophil purification exploit those properties of basophils which distinguish them from other cell types such as their localization in blood, density, and the presence or absence of surface markers. Purification techniques have been used in various combinations and variations to achieve a common goal in mind: to obtain a pure population of human basophils in sufficient numbers for downstream studies. The arduous way leading up to the modern protocols is summarized in this historical retrospective. A fast protocol for purification of basophils to near homogeneity is also described.

  5. Purification of polymorphic components of complex genomes

    DOEpatents

    Stodolsky, Marvin

    1991-01-01

    A method is disclosed for processing related subject and reference macromolecule populations composed of complementary strands into their respective subject and reference populations of representative fragments and effectuating purification of unique polymorphic subject fragments.

  6. Accelerated purification of colloidal silica sols

    NASA Technical Reports Server (NTRS)

    Bahnsen, E. B.; Garofalini, S.; Pechman, A.

    1979-01-01

    Accelerated purification process for colloidal sols using heat/deionization scheme, sharply reduces waiting time between deionization cycles from several months to a few days. Process produces same high purity silica sols as conventional methods.

  7. Purification of swine haptoglobin by affinity chromatography.

    PubMed Central

    Eurell, T E; Hall, W F; Bane, D P

    1990-01-01

    A globin-agarose affinity chromatography technique was used to purify swine haptoglobin. This technique provides a highly specific, single-step purification method without the contamination of extraneous serum proteins reported by previous studies. Complex formation between the haptoglobin isolate and swine hemoglobin confirmed that biological activity was maintained during the purification process. Immunoelectrophoretic and Ouchterlony immunodiffusion methods revealed that the swine haptoglobin isolate cross-reacted with polyvalent antisera against human haptoglobin. Images Fig. 2. Fig. 3. PMID:2123414

  8. Improved purification of rat intestinal lactase.

    PubMed

    Nsi-Emvo, E; Launay, J F; Raul, F

    1986-02-01

    A rapid and improved method to obtain purified lactase from rat intestine is described. The purification procedure involved only two chromatographic steps. The degree of purification was far above (500 fold) the values reached with classical methods. Rabbit antisera raised to the purified lactase were characterized using conventional immunological techniques. The specificity of the lactase antibodies was confirmed by the lack of interference on maltase, aminopeptidase and alkaline phosphatase activities measured after papain extraction of the membrane proteins.

  9. EUV tools: hydrogen gas purification and recovery strategies

    NASA Astrophysics Data System (ADS)

    Landoni, Cristian; Succi, Marco; Applegarth, Chuck; Riddle Vogt, Sarah

    2015-03-01

    The technological challenges that have been overcome to make extreme ultraviolet lithography (EUV) a reality have been enormous1. This vacuum driven technology poses significant purity challenges for the gases employed for purging and cleaning the scanner EUV chamber and source. Hydrogen, nitrogen, argon and ultra-high purity compressed dry air (UHPCDA) are the most common gases utilized at the scanner and source level. Purity requirements are tighter than for previous technology node tools. In addition, specifically for hydrogen, EUV tool users are facing not only gas purity challenges but also the need for safe disposal of the hydrogen at the tool outlet. Recovery, reuse or recycling strategies could mitigate the disposal process and reduce the overall tool cost of operation. This paper will review the types of purification technologies that are currently available to generate high purity hydrogen suitable for EUV applications. Advantages and disadvantages of each purification technology will be presented. Guidelines on how to select the most appropriate technology for each application and experimental conditions will be presented. A discussion of the most common approaches utilized at the facility level to operate EUV tools along with possible hydrogen recovery strategies will also be reported.

  10. Optimization of the electrically heated catalyst for emission purification efficiency

    SciTech Connect

    Jeong, L.; Jang, J.; Yeo, G.; Kim, Y.

    1996-09-01

    It is well known that the EHC (Electrically Heated Catalyst) is very effective for the reduction of cold-start hydrocarbon emissions. To optimize EHC applications for LEV (Low Emission Vehicle) and ULEV (Ultra Low Emission Vehicle) standards, the effects of heating and secondary air injection on the emission purification efficiency in FTP (Federal Test Procedure) were evaluated with three different EHC system configurations. The exhaust manifold location EHC system in which the EHC with a light-off catalyst is installed near the exhaust manifold, yields 0.038g/mile of THC (Total Hydrocarbon emissions) when the test was performed according to the FTP with an engine-aged condition equivalent to 50,000 miles. Therefore, the ULEV standards could be achieved through the system. A new battery system for the EHC and a single battery system for vehicle application were evaluated. Evaluation of the Ni-MH battery for EHC system is included.

  11. Purification and characterization of ribulose-5-phosphate kinase from spinach

    SciTech Connect

    Porter, M.A.; Milanez, S.; Stringer, C.D.; Hartman, F.C.

    1986-02-15

    An efficient purification procedure utilizing affinity chromatography is described for spinach ribulose-5-phosphate kinase, a light-regulated chloroplastic enzyme. Gel filtration and polyacrylamide gel electrophoresis of the purified enzyme reveal a dimeric structure of 44,000 Mr subunits. Chemical crosslinking with dimethyl suberimidate confirms the presence of two subunits per molecule of native kinase, which are shown to be identical by partial NH2-terminal sequencing. Based on sulfhydryl titrations and on amino acid analyses, each subunit contains four to five cysteinyl residues. The observed slow loss of activity during spontaneous oxidation in air-saturated buffer correlates with the intramolecular oxidation of two sulfhydryl groups, presumably those involved in thioredoxin-mediated regulation.

  12. Effect of purification pretreatment on the recovery of magnetite from waste ferrous sulfate

    NASA Astrophysics Data System (ADS)

    Yu, Wang; Peng, Ying-lin; Zheng, Ya-jie

    2016-08-01

    The present study was conducted to elucidate the influence of impurities in waste ferrous sulfate on its recovery of magnetite. Ferrous sulfate solution was purified by the addition of NaOH solution to precipitate impurities, and magnetite was recovered from ferrous sulfate solution without and with purification pretreatment. Calcium hydroxide was added to the solution of ferrous sulfate as a precipitator. A mixed product of magnetite and gypsum was subsequently obtained by air oxidation and heating. Wet-milling was performed prior to magnetic separation to recover magnetite from the mixed products. The results show that with the purification pretreatment, the grade of iron in magnetite concentrate increased from 62.05% to 65.58% and the recovery rate of iron decreased from 85.35% to 80.35%. The purification pretreatment reduced the conglutination between magnetite and gypsum, which favors their subsequent magnetic separation. In summary, a higher-grade magnetite with a better crystallinity and a larger particle size of 2.35 μm was obtained with the purification pretreatment.

  13. Air Pollution

    MedlinePlus

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, ... Ozone, a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

  14. Screening in humid air plasmas

    NASA Astrophysics Data System (ADS)

    Filippov, Anatoly; Derbenev, Ivan; Dyatko, Nikolay; Kurkin, Sergey

    2016-09-01

    Low temperature air plasmas containing H2O molecules are of high importance for atmospheric phenomena, climate control, biomedical applications, surface processing, and purification of air and water. Humid air plasma created by an external ionization source is a good model of the troposphere where ions are produced by the galactic cosmic rays and decay products of air and soil radioactive elements such as Rn222. The present paper is devoted to study the ionic composition and the screening in an ionized humid air at atmospheric pressure and room temperature. The ionization rate is varied in the range of 101 -1018 cm-3s-1. The humid air with 0 - 1 . 5 % water admixture that corresponds to the relative humidity of 0 - 67 % at the air temperature equal to 20°C is considered. The ionic composition is determined on the analysis of more than a hundred processes. The system of 41 non-steady state particle number balance equations is solved using the 4th order Runge-Kutta method. The screening of dust particle charge in the ionized humid air are studied within the diffusion-drift approach. The screening constants are well approximated by the inverse Debye length and characteristic lengths of recombination and attachment processes. This work was supported by the Russian Science Foundation, Project No. 16-12-10424.

  15. Dialysis membranes for blood purification.

    PubMed

    Sakai, K

    2000-01-01

    All of the artificial membranes in industrial use, such as a reverse-osmosis membrane, dialysis membrane, ultrafiltration membrane, microfiltration membrane and gas separation membrane, also have therapeutic applications. The most commonly used artificial organ is the artificial kidney, a machine that performs treatment known as hemodialysis. This process cleanses the body of a patient with renal failure by dialysis and filtration, simple physicochemical processes. Hemodialysis membranes are used to remove accumulated uremic toxins, excess ions and water from the patient via the dialysate, and to supply (deficit) insufficient ions from the dialysate. Dialysis membranes used clinically in the treatment of patients with renal failure account for by far the largest volume of membranes used worldwide; more than 70 million square meters are used a year. Almost all dialyzers now in use are of the hollow-fiber type. A hollow-fiber dialyzer contains a bundle of approximately 10000 hollow fibers, each with an inner diameter of about 200 microm when wet. The membrane thickness is about 20-45 microm, and the length is 160-250 mm. The walls of the hollow fibers function as the dialysis membrane. Various materials, including cellulose-based materials and synthetic polymers, are used for dialysis membranes. This paper reviews blood purification, hemodialysis and dialysis membranes.

  16. PURIFICATION OF STREPTOMYCES VENEZUELAE PHAGE

    PubMed Central

    Kolstad, R. A.; Bradley, S. G.

    1964-01-01

    Kolstad, R. A. (University of Minnesota, Minneapolis), and S. G. Bradley. Purification of Streptomyces venezuelae phage. J. Bacteriol. 87:1157–1161. 1964.—Streptomyces venezuelae phage MSP8 was concentrated and purified by a combination of methods including dialysis against polyethylene glycol, partitioning between the two phases of aqueous polymer systems, gel filtration, chromatography on ECTEOLA-cellulose, and differential centrifugation. S. venezuelae phage MSP8 is 57% deoxyribonucleic acid and 43% protein. Its head is 55 by 70 mμ, and its tail is 10 by 150 mμ. Its dry weight is 250 mg per 1015 plaqueforming units, and its density is 1.4. Phage MSP8 contains 15 μg of phosphorus and 40 μg of nitrogen per 1012 particles. The ratio of light absorbancy at 260 to 280 mμ is 1.5. A mixture of two actinophages, MNP3 and MVP7, was separated by use of ECTEOLA-cellulose. In one fraction, 99% of the phage was MNP3; in another fraction, 99% of the phage was MVP7. Images PMID:5874537

  17. Preparative parallel protein purification (P4).

    PubMed

    Strömberg, Patrik; Rotticci-Mulder, Joke; Björnestedt, Robert; Schmidt, Stefan R

    2005-04-15

    In state of the art drug discovery, it is essential to gain structural information of pharmacologically relevant proteins. Increasing the output of novel protein structures requires improved preparative methods for high throughput (HT) protein purification. Currently, most HT platforms are limited to small-scale and available technology for increasing throughput at larger scales is scarce. We have adapted a 10-channel parallel flash chromatography system for protein purification applications. The system enables us to perform 10 different purifications in parallel with individual gradients and UV monitoring. Typical protein purification applications were set up. Methods for ion exchange chromatography were developed for different sample proteins and columns. Affinity chromatography was optimized for His-tagged proteins using metal chelating media and buffer exchange by gel filtration was also tested. The results from the present system were comparable, with respect to resolution and reproducibility, with those from control experiments on an AKTA purifier system. Finally, lysates from 10 E. coli cultures expressing different His-tagged proteins were subjected to a three-step parallel purification procedure, combining the above-mentioned procedures. Nine proteins were successfully purified whereas one failed probably due to lack of expression.

  18. Purification of fallout-contaminated water studied

    SciTech Connect

    Lu Deyuan; Cai, X.; Li, M.; Liu, T.

    1983-04-30

    This article presents data from an experiment conducted in China in which the ability of certain purification materials and drinking water decontaminants were tested with water polluted by fallout from nuclear explosions. It is explained that the explosion of nuclear weapons or the dissemination of radioactive agents in a future war may pollute drinking water and water sources, creating a danger to human health. The experimental data indicate that the ''Drinking Water Decontamination and Purification Agent'' (DDPA) has a higher purification effectiveness than the ''Drinking Water Purification Powder'' (DPP) for falloutcontaminated water and /sup 131/I-contaminated water, while the ''Aqueous /sup 131/I Radioactivity Purifier'' (AIRP) has a higher purification effectiveness than DPP for /sup 131/I-contaminated water. DDPA consists of potassium permanganate, ferrous sulfate, ferric sulfate, disodium phosphate, No. 2 activated charcoal, earth, barium hydroxide, alum, and aluminium hydroxychloride. DPP consists of activated charcoal, bentonite, sodium phosphate, silver sulfate and aluminium hydroxychloride. AIRP consists of potassium permanganate, ferrous sulfate, ferric sulfate, disodium phosphate, No. 2 activated charcoal, earth, and aluminium hydroxychloride. It is concluded that the 13 common materials tested are effective in purifying radioactive water. Includes 2 tables.

  19. 21 CFR 876.5665 - Water purification system for hemodialysis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Water purification system for hemodialysis. 876... SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5665 Water purification system for hemodialysis. (a) Identification. A water purification system for hemodialysis is...

  20. 21 CFR 876.5665 - Water purification system for hemodialysis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Water purification system for hemodialysis. 876... SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5665 Water purification system for hemodialysis. (a) Identification. A water purification system for hemodialysis is...

  1. 21 CFR 876.5665 - Water purification system for hemodialysis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Water purification system for hemodialysis. 876... SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5665 Water purification system for hemodialysis. (a) Identification. A water purification system for hemodialysis is...

  2. The role of a hybrid phytosystem in landscape water purification and herbicides removal.

    PubMed

    Kirumba, George; Ge, Ling; Wei, Dongyang; Xu, Cong; He, Yiliang; Zhang, Bo; Jiang, Cheng; Mao, Feijian

    2015-01-01

    The performance of a hybrid phytosystem in landscape water purification and herbicides removal was investigated. The phytosystem operating in an arboretum is located in the Minhang Campus of Shanghai Jiao Tong University, China. The phytosystem is composed of two purification stages: sedimentation Stage 1 without external air supply; and Stage 2 with an external air supply. Stage 2 is also vegetated with three major kinds of plants, namely Pontederia cordata L., Typha latifolia L. and Cyperus alternifolius L. The system's hydraulic loading rate (HLR) was maintained at 1.632 m/day between December 2013 and November 2014. Sedimentation, filtration and adsorption by filter media, combined microbial processes in the rhizosphere (nitrification-denitrification) and plant uptake of the pollutants were all responsible for water purification in the phytosystem. The biological and physical parameters analyzed were total dissolved nitrogen (TDN), nitrate (NO3-N), nitrite (NO2-N), ammonia (NH3-N), total dissolved phosphorus (TDP), dissolved organic carbon (DOC), turbidity, chlorophyll-a and algal cells number. Highest removal efficiencies for TDN, TDP, turbidity, DOC, chlorophyll-a and algal cells were 56.9%, 73.3%, 92.4%, 29.9%, 94.3% and 91.0%, respectively. When the phytosystem was considered for herbicides removal, removal efficiencies of more than 25% were noted for all the herbicides.

  3. Purification of Carbon Nanotubes: Alternative Methods

    NASA Technical Reports Server (NTRS)

    Files, Bradley; Scott, Carl; Gorelik, Olga; Nikolaev, Pasha; Hulse, Lou; Arepalli, Sivaram

    2000-01-01

    Traditional carbon nanotube purification process involves nitric acid refluxing and cross flow filtration using surfactant TritonX. This is believed to result in damage to nanotubes and surfactant residue on nanotube surface. Alternative purification procedures involving solvent extraction, thermal zone refining and nitric acid refiuxing are used in the current study. The effect of duration and type of solvent to dissolve impurities including fullerenes and P ACs (polyaromatic compounds) are monitored by nuclear magnetic reasonance, high performance liquid chromatography, and thermogravimetric analysis. Thermal zone refining yielded sample areas rich in nanotubes as seen by scanning electric microscopy. Refluxing in boiling nitric acid seem to improve the nanotube content. Different procedural steps are needed to purify samples produced by laser process compared to arc process. These alternative methods of nanotube purification will be presented along with results from supporting analytical techniques.

  4. Purification of glycocalicin from human plasma.

    PubMed

    HadjKacem, Basma; Mkaouar, Héla; Ben Amor, Ikram; Gargouri, Jalel; Gargouri, Ali

    2016-01-01

    Glycocalicin (GC) is a large extracellular proteolytic fragment of glycoprotein Ib, a membrane platelet component playing an essential role in the physiological processes of platelet adhesion and aggregation. GC contains the binding sites for thrombin and von Willebrand factor. GC circulates normally in vivo in significant concentrations and the plasma level of this protein reflects a complex function of factors including platelet count or platelet turnover. It can therefore serve as a good indicator for many diseases like hypoplastic thrombocytopenia and idiopathic thrombocytopenic purpura. For this reason, several purification assays have been previously described. In this work, we describe a novel analytical method for GC purification from human platelets based on preparative HPLC gel filtration followed by immuno-affinity chromatography on NHS activated column conjugated with specific antibody. Pure GC was obtained from tiny amount of starting material. Our protocol of GC purification is simple, fast and provides a pure end product.

  5. CHARACTERIZATION OF OZONE EMISSIONS FROM AIR CLEANERS EQUIPPED WITH OZONE GENERATORS AND SENSOR AND FEEDBACK CONTROL CIRCUITRY

    EPA Science Inventory

    The paper give results of a characterization of ozone emissions from air cleaners equipped with ozone generators and sensor and feedback control circuitry. Ozone emission rates of several consumer appliances, marketed as indoor air treatment or air purification systems, were det...

  6. CHARACTERIZATION OF OZONE EMISSIONS FROM AIR CLEANERS EQUIPPED WITH OZONE GENERATORS AND SENSOR AND FEEDBACK CONTROL CIRCUITRY

    EPA Science Inventory

    The paper give results of a characterization of ozone emissions from air cleaners equipped with ozone generators and sensor and feedback control circuitry. Ozone emission rates of several consumer appliances, marketed as indoor air treatment or air purification systems, were det...

  7. Soft-Bake Purification of SWCNTs Produced by Pulsed Laser Vaporization

    NASA Technical Reports Server (NTRS)

    Yowell, Leonard; Nikolaev, Pavel; Gorelik, Olga; Allada, Rama Kumar; Sosa, Edward; Arepalli, Sivaram

    2013-01-01

    The "soft-bake" method is a simple and reliable initial purification step first proposed by researchers at Rice University for single-walled carbon nanotubes (SWCNT) produced by high-pressure carbon mon oxide disproportionation (HiPco). Soft-baking consists of annealing as-produced (raw) SWCNT, at low temperatures in humid air, in order to degrade the heavy graphitic shells that surround metal particle impurities. Once these shells are cracked open by the expansion and slow oxidation of the metal particles, the metal impurities can be digested through treatment with hydrochloric acid. The soft-baking of SWCNT produced by pulsed-laser vaporization (PLV) is not straightforward, because the larger average SWCNT diameters (.1.4 nm) and heavier graphitic shells surrounding metal particles call for increased temperatures during soft-bake. A part of the technology development focused on optimizing the temperature so that effective cracking of the graphitic shells is balanced with maintaining a reasonable yield, which was a critical aspect of this study. Once the ideal temperature was determined, a number of samples of raw SWCNT were purified using the soft-bake method. An important benefit to this process is the reduced time and effort required for soft-bake versus the standard purification route for SWCNT. The total time spent purifying samples by soft-bake is one week per batch, which equates to a factor of three reduction in the time required for purification as compared to the standard acid purification method. Reduction of the number of steps also appears to be an important factor in improving reproducibility of yield and purity of SWCNT, as small deviations are likely to get amplified over the course of a complicated multi-step purification process.

  8. Cadmium purification with a vibrating reactor

    SciTech Connect

    Torres, N.; Esna-Ashari, M.; Biallas, H.; Kangas, K.

    1986-08-01

    While electrolytically producing zinc from sulfide concentrates, purification is the most significant step. Impurities such as Co, Sn, Ge, Ni and Sb can cause extensive redissolution of the electrodeposited zinc, thus diminishing current efficiency. Other metals, particularly cadmium, lead and copper, can negatively affect zinc properties by deposition on the cathode. It is standard practice to use atomized zinc dust as a reducing agent in the purification process, either alone or combined with additives. In conventional operations, special facilities are necessary to produce zinc dust in an amount close to 8wt% of cathode production. This paper examines a technique which makes use of zinc granules instead of dust.

  9. Catalytic partial oxidation coupled with membrane purification to improve resource and energy efficiency in syngas production.

    PubMed

    Iaquaniello, G; Salladini, A; Palo, E; Centi, G

    2015-02-01

    Catalytic partial oxidation coupled with membrane purification is a new process scheme to improve resource and energy efficiency in a well-established and large scale-process like syngas production. Experimentation in a semi industrial-scale unit (20 Nm(3)  h(-1) production) shows that a novel syngas production scheme based on a pre-reforming stage followed by a membrane for hydrogen separation, a catalytic partial oxidation step, and a further step of syngas purification by membrane allows the oxygen-to-carbon ratio to be decreased while maintaining levels of feed conversion. For a total feed conversion of 40 %, for example, the integrated novel architecture reduces oxygen consumption by over 50 %, with thus a corresponding improvement in resource efficiency and an improved energy efficiency and economics, these factors largely depending on the air separation stage used to produce pure oxygen.

  10. Chemical looping integration with a carbon dioxide gas purification unit

    DOEpatents

    Andrus, Jr., Herbert E.; Jukkola, Glen D.; Thibeault, Paul R.; Liljedahl, Gregory N.

    2017-01-24

    A chemical looping system that contains an oxidizer and a reducer is in fluid communication with a gas purification unit. The gas purification unit has at least one compressor, at least one dryer; and at least one distillation purification system; where the gas purification unit is operative to separate carbon dioxide from other contaminants present in the flue gas stream; and where the gas purification unit is operative to recycle the contaminants to the chemical looping system in the form of a vent gas that provides lift for reactants in the reducer.

  11. Comparison of Purification Solutions With Different Osmolality for Porcine Islet Purification

    PubMed Central

    Miyagi-Shiohira, Chika; Kobayashi, Naoya; Saitoh, Issei; Watanabe, Masami; Noguchi, Yasufumi; Matsushita, Masayuki; Noguchi, Hirofumi

    2017-01-01

    The osmolality of the purification solution is one of the most critical variables in human islet purification during islet isolation. We previously reported the effectiveness of a combined continuous density/osmolality gradient for the supplemental purification of human islets. We herein applied a combined continuous density/osmolality gradient for regular purification. The islets were purified with a continuous density gradient without osmolality preparation [continuous density/normal osmolality (CD/NO)] or continuous density/osmolality solution with osmolality preparation by 10× Hank’s balanced salt solution (HBSS) [continuous density/continuous osmolality (CD/CO)]. The osmolality of the low-density solution was 400 mOsm/kg in both groups and that of the high-density solution was 410 mOsm/kg in the CD/NO group and 500 mOsm/kg in the CD/CO group. Unexpectedly, we noted no significant differences between the two solutions in terms of the islet yield, rate of viability and purity, score, stimulation index, or the attainability and suitability of posttransplantation normoglycemia. Despite reports that the endocrine and exocrine tissues of pancreata have distinct osmotic sensitivities and that high-osmolality solutions result in greater purification efficiency, the isolation and transplant outcomes did not markedly differ between the two purification solutions with different osmolalities in this study. PMID:28174675

  12. Rapid purification of fluorescent enzymes by ultrafiltration

    NASA Technical Reports Server (NTRS)

    Benjaminson, M. A.; Satyanarayana, T.

    1983-01-01

    In order to expedite the preparation of fluorescently tagged enzymes for histo/cytochemistry, a previously developed method employing gel column purification was compared with a more rapid modern technique using the Millipore Immersible CX-ultrafilter. Microscopic evaluation of the resulting conjugates showed comparable products. Much time and effort is saved using the new technique.

  13. Rapid purification of fluorescent enzymes by ultrafiltration

    NASA Technical Reports Server (NTRS)

    Benjaminson, M. A.; Satyanarayana, T.

    1983-01-01

    In order to expedite the preparation of fluorescently tagged enzymes for histo-cyctochemistry, a previously developed method employing gel column purification was compared with a more rapid modern technique using the Millipore Immersible CX-ultrafilter. Microscopic evaluation of the resulting conjugates showed comparable products. Much time and effort is saved using the new technique.

  14. Purification of tantalum by plasma arc melting

    DOEpatents

    Dunn, Paul S.; Korzekwa, Deniece R.

    1999-01-01

    Purification of tantalum by plasma arc melting. The level of oxygen and carbon impurities in tantalum was reduced by plasma arc melting the tantalum using a flowing plasma gas generated from a gas mixture of helium and hydrogen. The flowing plasma gases of the present invention were found to be superior to other known flowing plasma gases used for this purpose.

  15. Isolation and purification of duck liver ferritin.

    PubMed

    Díez, J M; Agapito, M T; Recio, J M

    1985-09-01

    A rapid method of purifying duck liver ferritin using high speed centrifugation and chromatography on Sephadex G-200 and Sepharose 6B is described. Protein and iron concentration for each step of purification is given. This method yields 0.12 mg of pure ferritin per gram of wet tissue.

  16. Purification of functionalized DNA origami nanostructures.

    PubMed

    Shaw, Alan; Benson, Erik; Högberg, Björn

    2015-05-26

    The high programmability of DNA origami has provided tools for precise manipulation of matter at the nanoscale. This manipulation of matter opens up the possibility to arrange functional elements for a diverse range of applications that utilize the nanometer precision provided by these structures. However, the realization of functionalized DNA origami still suffers from imperfect production methods, in particular in the purification step, where excess material is separated from the desired functionalized DNA origami. In this article we demonstrate and optimize two purification methods that have not previously been applied to DNA origami. In addition, we provide a systematic study comparing the purification efficacy of these and five other commonly used purification methods. Three types of functionalized DNA origami were used as model systems in this study. DNA origami was patterned with either small molecules, antibodies, or larger proteins. With the results of our work we aim to provide a guideline in quality fabrication of various types of functionalized DNA origami and to provide a route for scalable production of these promising tools.

  17. Expression and Purification of Sperm Whale Myoglobin

    ERIC Educational Resources Information Center

    Miller, Stephen; Indivero, Virginia; Burkhard, Caroline

    2010-01-01

    We present a multiweek laboratory exercise that exposes students to the fundamental techniques of bacterial expression and protein purification through the preparation of sperm whale myoglobin. Myoglobin, a robust oxygen-binding protein, contains a single heme that gives the protein a reddish color, making it an ideal subject for the teaching…

  18. Expression and Purification of Sperm Whale Myoglobin

    ERIC Educational Resources Information Center

    Miller, Stephen; Indivero, Virginia; Burkhard, Caroline

    2010-01-01

    We present a multiweek laboratory exercise that exposes students to the fundamental techniques of bacterial expression and protein purification through the preparation of sperm whale myoglobin. Myoglobin, a robust oxygen-binding protein, contains a single heme that gives the protein a reddish color, making it an ideal subject for the teaching…

  19. PREPARATION AND PURIFICATION OF SILICON CARBIDE.

    DTIC Science & Technology

    the materials were divided into two parts. Part I covers problems of silicon carbide preparation and the growing of silicon carbide single crystals...and thin films for semiconductor devices. Part II treats problems of purity, including the purification and chemical analysis of silicon carbide and of starting materials for silicon carbide preparation.

  20. Protocol for Initial Purification of Bacteriocin

    DTIC Science & Technology

    2015-10-01

    bacteria by out-competing them for resources while leaving beneficial bacteria unaffected. One of the limiting factors for the commercialization of...PREPARATION SOLUBLE EXTRACTS COLUMN CHROMATOGRAPHY BACTERIA PURIFICATION CHARACTERIZATION...3  6.1  Preparation of Target Bacteria

  1. Air Revitalization System Enables Excursions to the Stratosphere

    NASA Technical Reports Server (NTRS)

    2015-01-01

    Paragon Space Development Corporation, based in Tucson, Arizona has had a long history of collaboration with NASA, including developing a modular air purification system under the Commercial Crew Development Program, designed to support the commercial space sector. Using that device and other NASA technology, startup company World View is now gearing up to take customers on helium balloon rides to the stratosphere.

  2. Air Abrasion

    MedlinePlus

    ... delivered directly to your desktop! more... What Is Air Abrasion? Article Chapters What Is Air Abrasion? What Happens? The Pros and Cons Will I Feel Anything? Is Air Abrasion for Everyone? print full article print this ...

  3. Magneto-capillary valve for integrated purification and enrichment of nucleic acids and proteins.

    PubMed

    den Dulk, Remco C; Schmidt, Kristiane A; Sabatté, Gwénola; Liébana, Susana; Prins, Menno W J

    2013-01-07

    We describe the magneto-capillary valve (MCV) technology, a flexible approach for integrated biological sample preparation within the concept of stationary microfluidics. Rather than moving liquids in a microfluidic device, discrete units of liquid are present at fixed positions in the device and magnetic particles are actuated between the fluids. The MCV concept is characterized by the use of two planar surfaces at a capillary mutual distance, with specific features to confine the fluids by capillary forces, and the use of a gas or a phase-change material separating the stationary aqueous liquids. We have studied the physics of magneto-capillary valving by quantifying the magnetic force as a function of time and position, which reveals the balance of magnetic, capillary and frictional forces in the system. By purification experiments with a fluorescent tracer we have measured the amount of co-transported liquid, which is a key parameter for efficient purification. To demonstrate the versatility of the technology, several MCV device architectures were tested in a series of biological assays, showing the purification and enrichment of nucleic acids and proteins. Target recovery comparable to non-miniaturized commercial kits was observed for the extraction of DNA from human cells in buffer, using a device architecture with patterned air valves. Experiments using an enrichment module and patterned air valves demonstrate a 40-fold effective enrichment of DNA in buffer. DNA was also successfully purified from blood plasma using paraffin phase-change valves. Finally, the enrichment of a protein biomarker (prostate-specific antigen) using geometrical air valves resulted in a 7-fold increase of detection signal. The MCV technology is versatile, offers extensive freedom for the design of fully integrated systems, and is expected to be manufacturable in a cost-effective way. We conclude that the MCV technology can become an important enabling technology for point

  4. Purification of nanoparticles by hollow fiber diafiltration

    NASA Astrophysics Data System (ADS)

    Veeken, J.

    2012-09-01

    Hollow Fiber Diafiltration (Hollow Fiber Tangential Flow Filtration) is an efficient and rapid alternative to traditional methods of nanoparticle purification such as ultracentrifugation, stirred cell filtration, dialysis or chromatography. Hollow Fiber Diafiltration can be used to purify a wide range of nanoparticles including liposomes, colloids, magnetic particles and nanotubes. Hollow Fiber Diafiltration is a membrane based method where pore size determines the retention or transmission of solution components. It is a flow process where the sample is gently circulated through a tubular membrane. With controlled replacement of the permeate or (dialysate), pure nanoparticles can be attained. Hollow Fiber Diafiltration can be directly scaled up from R&D volumes to production. By adding more membrane fibers and maintaining the operating parameters, large volumes can be processed in the same time with the same pressure, and flow dynamics as bench-scale volumes. Keywords: hollow fiber, Diafiltration, filtration, purification, tangential flow filtration.

  5. Purification of polonium-210 using pyrochemical extraction

    SciTech Connect

    Wheelwright, E.J.; Swanson, J.L.; Myers, T.R.

    1980-05-01

    An efficient extraction process that does not utilize halides or organic solvents has been developed for the recovery and purification of /sup 210/Po. Polonium-210, produced in bismuth metal by neutron irradiation, is extracted from molten bismuth metal into molten NaOH in an unique 3-compartment contactor under an inert atmosphere. At a temperature of 450+-25/sup 0/C, and at a NaOH/Bi weight ratio of 0.044, five successive 60-minute extractions remove > 96% of the /sup 210/Po. Following phase separation and freezing, additional purification steps include dissolution of the solidified NaOH in HNO/sub 3/, recovery of /sup 210/Po from this solution by MnO/sub 2/ carrier precipitation, dissolution of the precipitate by H/sub 2/O/sub 2/ in HNO/sub 3/, and , finally, electrodeposition of /sup 210/Po onto platinum gauze.

  6. Nanomaterials and Water Purification: Opportunities and Challenges

    NASA Astrophysics Data System (ADS)

    Savage, Nora; Diallo, Mamadou S.

    2005-10-01

    Advances in nanoscale science and engineering suggest that many of the current problems involving water quality could be resolved or greatly ameliorated using nanosorbents, nanocatalysts, bioactive nanoparticles, nanostructured catalytic membranes and nanoparticle enhanced filtration among other products and processes resulting from the development of nanotechnology. Innovations in the development of novel technologies to desalinate water are among the most exciting and promising. Additionally, nanotechnology-derived products that reduce the concentrations of toxic compounds to sub-ppb levels can assist in the attainment of water quality standards and health advisories. This article gives an overview of the use of nanomaterials in water purification. We highlight recent advances on the development of novel nanoscale materials and processes for treatment of surface water, groundwater and industrial wastewater contaminated by toxic metal ions, radionuclides, organic and inorganic solutes, bacteria and viruses. In addition, we discuss some challenges associated with the development of cost effective and environmentally acceptable functional nanomaterials for water purification.

  7. Purification of Logic-Qubit Entanglement

    PubMed Central

    Zhou, Lan; Sheng, Yu-Bo

    2016-01-01

    Recently, the logic-qubit entanglement shows its potential application in future quantum communication and quantum network. However, the entanglement will suffer from the noise and decoherence. In this paper, we will investigate the first entanglement purification protocol for logic-qubit entanglement. We show that both the bit-flip error and phase-flip error in logic-qubit entanglement can be well purified. Moreover, the bit-flip error in physical-qubit entanglement can be completely corrected. The phase-flip in physical-qubit entanglement error equals to the bit-flip error in logic-qubit entanglement, which can also be purified. This entanglement purification protocol may provide some potential applications in future quantum communication and quantum network. PMID:27377165

  8. Fractional purification and bioconversion of hemicelluloses.

    PubMed

    Peng, Feng; Peng, Pai; Xu, Feng; Sun, Run-Cang

    2012-01-01

    Hemicelluloses are types of plant cell wall polysaccharides, and the world's second most abundant renewable polymers after cellulose in lignocellulosic materials. They represent a type of hetero-polysaccharide with complex structure containing glucose, xylose, mannose, galactose, arabinose, rhamnose, glucuronic acid, and galacturonic acid in various amounts, depending on the source. Hemicelluloses are usually bonded to other cell-wall components such as cellulose, cell-wall proteins, lignin, and phenolic compounds by covalent and hydrogen bonds, and by ionic and hydrophobic interactions. This paper provides a review on hemicelluloses from lignocellulosic materials, especially in regard to their isolation and purification methods, and bioconversion. Current isolation and purification strategies are summarized, including: alkali peroxide extraction, organic solvent extraction, steam explosion, ultrasound-assisted extraction, microwave-assisted extraction, column chromatography, and membrane separation. In addition, the bioconversion of hemicelluloses including pretreatment, enzymatic hydrolysis, and fermentation are discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. A simple method for the purification of Eimeria tenella sporozoites.

    PubMed

    Mattig, F R; Drössigk, U; Entzeroth, R

    1993-05-01

    A rapid, simple and cheap method for the purification of Eimeria tenella sporozoites has been developed using commercially available filter paper (595 filter paper circles, Schleicher & Schuell, 3354 Dassel, Germany, order 311610). Yield and purity are of the same value as by purification with a leukopac column (Bontemps & Yvore 1974). The described method can be used for the purification of Eimeria tenella sporozoites under sterile conditions for subsequent in vitro cultivation.

  10. Semiconductor grade, solar silicon purification project

    NASA Technical Reports Server (NTRS)

    Ingle, W. M.; Thompson, S.; Rosler, D.; Jackson, J.

    1977-01-01

    The conversion of metallurgical grade silicon into semiconductor grade silicon by way of a three step SiF2 polymer transport purification process was investigated. Developments in the following areas were also examined: (1) spectroscopic analysis and characterization of (SiF2) sub x polymer and Si sub x F sub y homologue conversion; (2) demonstration runs on the near continuous apparatus; (3) economic analysis; and (4) elemental analysis.

  11. APPARATUS FOR THE PURIFICATION OF CALCIUM

    DOEpatents

    Burnett, R.L.

    1953-08-25

    The present patent claims and describes an apparatus adapted to carry out a new process for the purification of calcium containing an alkali metal as impurity. The process consists of distilling the impure caldium in the presence of an inert gas and at a reduced pressure, condensing substantially pure calcium on a condensing surface of iron or a ferrous alloy and condensing the alkali metal on a separate surface, the two condensing surfaces being maintained at suitable temperatures by separate cooling means.

  12. Purification of metal-organic framework materials

    DOEpatents

    Farha, Omar K.; Hupp, Joseph T.

    2015-06-30

    A method of purification of a solid mixture of a metal-organic framework (MOF) material and an unwanted second material by disposing the solid mixture in a liquid separation medium having a density that lies between those of the wanted MOF material and the unwanted material, whereby the solid mixture separates by density differences into a fraction of wanted MOF material and another fraction of unwanted material.

  13. Purification of metal-organic framework materials

    SciTech Connect

    Farha, Omar K.; Hupp, Joseph T.

    2012-12-04

    A method of purification of a solid mixture of a metal-organic framework (MOF) material and an unwanted second material by disposing the solid mixture in a liquid separation medium having a density that lies between those of the wanted MOF material and the unwanted material, whereby the solid mixture separates by density differences into a fraction of wanted MOF material and another fraction of unwanted material.

  14. Immunological purification of sea urchin egg tropomyosin.

    PubMed

    Ishimoda-Takagi, T

    1978-06-01

    The antiserum against lantern muscle tropomyosin of the sea urchin was prepared, and the presence of tropomyosin in the sea urchin egg was shown by immunodiffusion test between the antiserum and the egg tropomyosin fraction which was prepared according to the purification method for muscle tropomyosin. The sea urchin egg tropomyosin was isolated from the immuno-precipitate formed between the antiserum and the egg tropomyosin fraction. The subunit molecular weight of the egg tropomyosin was calculated to be 29,000.

  15. Purification of GST-Tagged Proteins.

    PubMed

    Schäfer, Frank; Seip, Nicole; Maertens, Barbara; Block, Helena; Kubicek, Jan

    2015-01-01

    This protocol describes the purification of recombinant proteins fused to glutathione S-transferase (GST, GST-tagged proteins) by Glutathione Affinity purification. The GST tag frequently increases the solubility of the fused protein of interest and thus enables its purification and subsequent functional characterization. The GST-tagged protein specifically binds to glutathione immobilized to a matrix (e.g., agarose) and can be easily separated from a cell lysate by a bind-wash-elute procedure. GST-tagged proteins are often used to study protein-protein interactions, again making use of glutathione affinity in a procedure called a GST pull-down assay. The protocol is designed to process 200 ml of E. coli culture expressing intermediate to high amounts of a GST-tagged protein (~25 mg l(-1)). Depending on the expression rate or the available culture volume, the scale can be increased or decreased linearly. The protocol can also be used to purify GST-tagged proteins from other expression systems, such as insect or mammalian cells. Tips are provided to aid in modifying certain steps if proteins shall be recovered from alternative expression systems. © 2015 Elsevier Inc. All rights reserved.

  16. Microscale purification of antigen-specific antibodies

    PubMed Central

    Brown, Eric P.; Normandin, Erica; Osei-Owusu, Nana Yaw; Mahan, Alison E.; Chan, Ying N.; Lai, Jennifer I.; Vaccari, Monica; Rao, Mangala; Franchini, Genoveffa; Alter, Galit; Ackerman, Margaret E.

    2015-01-01

    Glycosylation of the Fc domain is an important driver of antibody effector function. While assessment of antibody glycoform compositions observed across total plasma IgG has identified differences associated with a variety of clinical conditions, in many cases it is the glycosylation state of only antibodies against a specific antigen or set of antigens that may be of interest, for example, in defining the potential effector function of antibodies produced during disease or after vaccination. Historically, glycoprofiling such antigen-specific antibodies in clinical samples has been challenging due to their low prevalence, the high sample requirement for most methods of glycan determination, and the lack of high-throughput purification methods. New methods of glycoprofiling with lower sample requirements and higher throughput have motivated the development of microscale and automatable methods for purification of antigen-specific antibodies from polyclonal sources such as clinical serum samples. In this work, we present a robot-compatible 96-well plate-based method for purification of antigen-specific antibodies, suitable for such population level glycosylation screening. We demonstrate the utility of this method across multiple antibody sources, using both purified plasma IgG and plasma, and across multiple different antigen types, with enrichment factors greater than 1000-fold observed. Using an on-column IdeS protease treatment, we further describe staged release of Fc and Fab domains, allowing for glycoprofiling of each domain. PMID:26078040

  17. Overview of the purification of recombinant proteins.

    PubMed

    Wingfield, Paul T

    2015-04-01

    When the first version of this unit was written in 1995, protein purification of recombinant proteins was based on a variety of standard chromatographic methods and approaches, many of which were described and mentioned throughout Current Protocols in Protein Science. In the interim, there has been a shift toward an almost universal usage of the affinity or fusion tag. This may not be the case for biotechnology manufacture where affinity tags can complicate producing proteins under regulatory conditions. Regardless of the protein expression system, questions are asked as to which and how many affinity tags to use, where to attach them in the protein, and whether to engineer a self-cleavage system or simply leave them on. We will briefly address some of these issues. Also, although this overview focuses on E.coli, protein expression and purification, other commonly used expression systems are mentioned and, apart from cell-breakage methods, protein purification methods and strategies are essentially the same. Copyright © 2015 John Wiley & Sons, Inc.

  18. Solvent-extraction purification of neptunium

    SciTech Connect

    Kyser, E.A.; Hudlow, S.L.

    2008-07-01

    The Savannah River Site (SRS) has recovered {sup 237}Np from reactor fuel that is currently being processed into NpO{sub 2} for future production of {sup 238}Pu. Several purification flowsheets have been utilized. An oxidizing solvent-extraction (SX) flowsheet was used to remove Fe, sulfate ion, and Th while simultaneously {sup 237}Np, {sup 238}Pu, u, and nonradioactive Ce(IV) was extracted into the tributyl phosphate (TBP) based organic solvent. A reducing SX flowsheet (second pass) removed the Ce and Pu and recovered both Np and U. The oxidizing flowsheet was necessary for solutions that contained excessive amounts of sulfate ion. Anion exchange was used to perform final purification of Np from Pu, U, and various non-actinide impurities. The Np(IV) in the purified solution was then oxalate-precipitated and calcined to an oxide for shipment to other facilities for storage and future target fabrication. Performance details of the SX purification and process difficulties are discussed. (authors)

  19. Rotating Reverse-Osmosis for Water Purification

    NASA Technical Reports Server (NTRS)

    Lueptow, RIchard M.

    2004-01-01

    A new design for a water-filtering device combines rotating filtration with reverse osmosis to create a rotating reverse- osmosis system. Rotating filtration has been used for separating plasma from whole blood, while reverse osmosis has been used in purification of water and in some chemical processes. Reverse- osmosis membranes are vulnerable to concentration polarization a type of fouling in which the chemicals meant not to pass through the reverse-osmosis membranes accumulate very near the surfaces of the membranes. The combination of rotating filtration and reverse osmosis is intended to prevent concentration polarization and thereby increase the desired flux of filtered water while decreasing the likelihood of passage of undesired chemical species through the filter. Devices based on this concept could be useful in a variety of commercial applications, including purification and desalination of drinking water, purification of pharmaceutical process water, treatment of household and industrial wastewater, and treatment of industrial process water. A rotating filter consists of a cylindrical porous microfilter rotating within a stationary concentric cylindrical outer shell (see figure). The aqueous suspension enters one end of the annulus between the inner and outer cylinders. Filtrate passes through the rotating cylindrical microfilter and is removed via a hollow shaft. The concentrated suspension is removed at the end of the annulus opposite the end where the suspension entered.

  20. Experimental purification of two-atom entanglement.

    PubMed

    Reichle, R; Leibfried, D; Knill, E; Britton, J; Blakestad, R B; Jost, J D; Langer, C; Ozeri, R; Seidelin, S; Wineland, D J

    2006-10-19

    Entanglement is a necessary resource for quantum applications--entanglement established between quantum systems at different locations enables private communication and quantum teleportation, and facilitates quantum information processing. Distributed entanglement is established by preparing an entangled pair of quantum particles in one location, and transporting one member of the pair to another location. However, decoherence during transport reduces the quality (fidelity) of the entanglement. A protocol to achieve entanglement 'purification' has been proposed to improve the fidelity after transport. This protocol uses separate quantum operations at each location and classical communication to distil high-fidelity entangled pairs from lower-fidelity pairs. Proof-of-principle experiments distilling entangled photon pairs have been carried out. However, these experiments obtained distilled pairs with a low probability of success and required destruction of the entangled pairs, rendering them unavailable for further processing. Here we report efficient and non-destructive entanglement purification with atomic quantum bits. Two noisy entangled pairs were created and distilled into one higher-fidelity pair available for further use. Success probabilities were above 35 per cent. The many applications of entanglement purification make it one of the most important techniques in quantum information processing.

  1. Strategies for the purification of membrane proteins.

    PubMed

    Smith, Sinead Marian

    2011-01-01

    Although membrane proteins account for 20-30% of the coding regions of all sequenced genomes and play crucial roles in many fundamental cell processes, there are relatively few membranes proteins with known 3D structure. This is likely due to technical challenges associated with membrane protein extraction, solubilisation, and purification. Membrane proteins are classified based on the level of interaction with membrane lipid bilayers, with peripheral membrane proteins associating non-covalently with the membrane, and integral membrane proteins associating more strongly by means of hydrophobic interactions. Generally speaking, peripheral membrane proteins can be purified by milder techniques than integral membrane proteins, whose extraction requires phospholipid bilayer disruption by detergents. Here, important criteria for strategies of membrane protein purification are addressed, with a focus on the initial stages of membrane protein solublilisation, where problems are most frequently encountered. Protocols are outlined for the successful extraction of peripheral membrane proteins, solubilisation of integral membrane proteins, and detergent removal which is important not only for retaining native protein stability and biological functions, but also for the efficiency of later purification techniques.

  2. Ethanol precipitation for purification of recombinant antibodies.

    PubMed

    Tscheliessnig, Anne; Satzer, Peter; Hammerschmidt, Nikolaus; Schulz, Henk; Helk, Bernhard; Jungbauer, Alois

    2014-10-20

    Currently, the golden standard for the purification of recombinant humanized antibodies (rhAbs) from CHO cell culture is protein A chromatography. However, due to increasing rhAbs titers alternative methods have come into focus. A new strategy for purification of recombinant human antibodies from CHO cell culture supernatant based on cold ethanol precipitation (CEP) and CaCl2 precipitation has been developed. This method is based on the cold ethanol precipitation, the process used for purification of antibodies and other components from blood plasma. We proof the applicability of the developed process for four different antibodies resulting in similar yield and purity as a protein A chromatography based process. This process can be further improved using an anion-exchange chromatography in flowthrough mode e.g. a monolith as last step so that residual host cell protein is reduced to a minimum. Beside the ethanol based process, our data also suggest that ethanol could be replaced with methanol or isopropanol. The process is suited for continuous operation.

  3. Microscale purification of antigen-specific antibodies.

    PubMed

    Brown, Eric P; Normandin, Erica; Osei-Owusu, Nana Yaw; Mahan, Alison E; Chan, Ying N; Lai, Jennifer I; Vaccari, Monica; Rao, Mangala; Franchini, Genoveffa; Alter, Galit; Ackerman, Margaret E

    2015-10-01

    Glycosylation of the Fc domain is an important driver of antibody effector function. While assessment of antibody glycoform compositions observed across total plasma IgG has identified differences associated with a variety of clinical conditions, in many cases it is the glycosylation state of only antibodies against a specific antigen or set of antigens that may be of interest, for example, in defining the potential effector function of antibodies produced during disease or after vaccination. Historically, glycoprofiling such antigen-specific antibodies in clinical samples has been challenging due to their low prevalence, the high sample requirement for most methods of glycan determination, and the lack of high-throughput purification methods. New methods of glycoprofiling with lower sample requirements and higher throughput have motivated the development of microscale and automatable methods for purification of antigen-specific antibodies from polyclonal sources such as clinical serum samples. In this work, we present a robot-compatible 96-well plate-based method for purification of antigen-specific antibodies, suitable for such population level glycosylation screening. We demonstrate the utility of this method across multiple antibody sources, using both purified plasma IgG and plasma, and across multiple different antigen types, with enrichment factors greater than 1000-fold observed. Using an on-column IdeS protease treatment, we further describe staged release of Fc and Fab domains, allowing for glycoprofiling of each domain. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Developing an Independent Helium Gas Purification System

    NASA Astrophysics Data System (ADS)

    Hughes, Carter; Tan, Wanpeng; Aprahamian, Ani; Lesher, Shelly

    2016-09-01

    The Institute for Structure and Nuclear Astrophysics depends on 3He for the study of Nuclear reactions. A 3He recovery system is necessary for the Helium Ion Source at the FN tandem accelerator, due to the prohibitive price of 3He. An offline 3He recovery and purification system was built based on the previous online recovery system. The previous online system purified helium gas at a very slow rate and required the Helium Ion Source to operate. The offline system is operated separate of the Helium Ion Source allowing for fast purification cycles. A re-circulation system was added to the offline system to improve the final purity of 3He. Different He gas flow rates were used in the offline purification system. The effects of flow rates were evaluated on their performance in the Helium Ion Source. Gas samples from different flow rates were then analyzed for contaminants in a Gas Chromatograph. Preliminary results and further improvements will be discussed. This work is supported by the National Science Foundation under Contract PHY-1205412 and NSF Proposal 1507053.

  5. Overview of the Purification of Recombinant Proteins

    PubMed Central

    Wingfield, Paul T.

    2015-01-01

    When the first version of this unit was written in 1995 protein purification of recombinant proteins was based on a variety of standard chromatographic methods and approaches many of which were described and mentioned in this unit and elsewhere in the book. In the interim there has been a shift towards an almost universal usage of the affinity or fusion tag. This may not be the case for biotechnology manufacture where affinity tags can complicate producing proteins under regulatory conditions. Regardless of the protein expression system, questions are asked as to which and how many affinity tags to use, where to attach them in the protein and whether to engineer a self cleavage system or simply leave them on. We will briefly address some of these issues. Also although this overview focuses on E.coli, protein expression and purification from the other commonly used expression systems are mentioned and apart from cell breakage methods, the protein purification methods and strategies are essentially the same. PMID:25829302

  6. Large scale purification of RNA nanoparticles by preparative ultracentrifugation.

    PubMed

    Jasinski, Daniel L; Schwartz, Chad T; Haque, Farzin; Guo, Peixuan

    2015-01-01

    Purification of large quantities of supramolecular RNA complexes is of paramount importance due to the large quantities of RNA needed and the purity requirements for in vitro and in vivo assays. Purification is generally carried out by liquid chromatography (HPLC), polyacrylamide gel electrophoresis (PAGE), or agarose gel electrophoresis (AGE). Here, we describe an efficient method for the large-scale purification of RNA prepared by in vitro transcription using T7 RNA polymerase by cesium chloride (CsCl) equilibrium density gradient ultracentrifugation and the large-scale purification of RNA nanoparticles by sucrose gradient rate-zonal ultracentrifugation or cushioned sucrose gradient rate-zonal ultracentrifugation.

  7. Air stripping. January 1980-February 1992 (Citations from the NTIS Data Base). Rept. for Jan 80-Feb 92

    SciTech Connect

    Not Available

    1992-02-01

    The bibliography contains citations concerning the application of air stripping techniques to water treatment, including groundwater decontamination and wastewater purification. The advantages and disadvantages of air stripping over other water treatment processes are discussed. Cleanup of the organic emissions generated by air stripping is also considered. The primary applications of air stripping are in groundwater and soil cleanup. (Contains 58 citations with title list and subject index.)

  8. Negative air ion effects on human performance and physiological condition.

    PubMed

    Buckalew, L W; Rizzuto, A P

    1984-08-01

    Beneficial effects of exposure to negative air ions have been suggested, to include improved performance, mood, attention, and physiological condition. Existing support is clouded by methodological problems of control and standardization in treatment and equipment. This study investigated effects of negative ions produced by a commercially marketed air purification device on grip magnitude, coding, motor dexterity, reaction time, tracking, pulse, blood pressure, and temperature. Two groups of 12 males were exposed to 6 continuous h of either negative or "normal" ion environments under a double blind condition. Repeated measures (0,3,6 h) on each variable were obtained. MANOVA applied to change scores revealed no differences between groups, and 0 vs. 3 and 0 vs. 6-h group differences showed no significant alteration in any measure. Negative ions generated by an air purification device were concluded to produce no general or specific alteration of cognitive or psychomotor performance or physiological condition.

  9. [Optimization of the indoor air conditioning in the places of excessive radon release].

    PubMed

    Malykhin, V M

    1994-01-01

    The experimental modelling covered ventilation and air purification as well as air pollution with radon and such derivatives as polonium-218b, lead-214 and bismuth-214. The modelling was designed for industrial conditions with higher radon release in technologic conversion at enterprises processing uranium. The investigators obtained some information to optimize air processing and to lower the workers exposure to radon and its derivatives.

  10. Air Pollution.

    ERIC Educational Resources Information Center

    Gilpin, Alan

    A summary of one of our most pressing environmental problems, air pollution, is offered in this book by the Director of Air Pollution Control for the Queensland (Australia) State Government. Discussion of the subject is not restricted to Queensland or Australian problems and policies, however, but includes analysis of air pollution the world over.…

  11. Air Pollution.

    ERIC Educational Resources Information Center

    Gilpin, Alan

    A summary of one of our most pressing environmental problems, air pollution, is offered in this book by the Director of Air Pollution Control for the Queensland (Australia) State Government. Discussion of the subject is not restricted to Queensland or Australian problems and policies, however, but includes analysis of air pollution the world over.…

  12. [A new purification methods of small DNAs--the purification methods with silica wool].

    PubMed

    Zhang, Jing; Ying, Tian-Yi; Gao, Chuan; Song, Yun-Yang; Han, Wei-Tao; Wang, Hui-Fang

    2006-05-01

    The principal purpose of this study is to set up efficient purification techniques of small DNAs which are suitable for isolation of from tens to three hundred bases of genes. On the bases of the technique, purification methods for big DNA fragments are established. In the experiment, the DNA bands were cut after agarose gel electrophoresis and put into 0.5 mL of tubes with silica wool, glass wood, absorbent cotton and cotton at the bottom. And then 10 000 r/min for 2 min, the liquid was collected. The results indicated that silica wool was the best of the materials. The recovery rate for DNAs below 200bp was over 90%, 85% to approximately 90% for 300bp. And the technique can be applied to purify bigger DNA fragments. The kits for DNA purification hardly recovered DNA below 150bp. The recovery rate for 150bp of DNA was 5%, 60% even for 300bp. The efficiencies of enzymic digestion and enzymic connection for the DNAs purified by the technique were the same as those for the DNAs isolated by the kits. So, the technique is obviously superior to kit purification methods.

  13. Necessity of Purification during Bacterial DNA Extraction with Environmental Soils.

    PubMed

    Lim, Hyun Jeong; Choi, Jung-Hyun; Son, Ahjeong

    2017-08-08

    Complexity and heterogeneity of soil samples have often implied the inclusion of purification steps in conventional DNA extraction for PCR assays. Unfortunately the purification steps are also time and labor intensive. Therefore the necessity of DNA purification was re-visited and investigated for a variety of environmental soil samples that contained various amounts of PCR inhibitors. Bead beating and centrifugation was used as the baseline (without purification) method for DNA extraction. Its performance was compared with that of conventional DNA extraction kit (with purification). The necessity criteria for DNA purification were established with environmental soil samples. Using lysis conditions at 3000 rpm for 3 minutes with 0.1 mm glass beads, centrifugation time of 10 minutes and 1:10 dilution ratio, the baseline method outperformed conventional DNA extraction on cell seeded sand samples. Further investigation with PCR inhibitors (i.e., humic acids, clay, and magnesium) showed that sand samples containing less than 10 ug/g humic acids and 70% clay may not require purifications. Interestingly, the inhibition pattern of magnesium ion was different from other inhibitors due to the complexation interaction of magnesium ion with DNA fragments. It was concluded that DNA extraction method without purification is suitable for soil samples that have less than 10 ug/g of humic acids, less than 70% clay content and less than 0.01% magnesium ion content.

  14. A scintillator purification system for the Borexino solar neutrino detector

    NASA Astrophysics Data System (ADS)

    Benziger, J.; Cadonati, L.; Calaprice, F.; Chen, M.; Corsi, A.; Dalnoki-Veress, F.; Fernholz, R.; Ford, R.; Galbiati, C.; Goretti, A.; Harding, E.; Ianni, Aldo; Ianni, Andrea; Kidner, S.; Leung, M.; Loeser, F.; McCarty, K.; McKinsey, D.; Nelson, A.; Pocar, A.; Salvo, C.; Schimizzi, D.; Shutt, T.; Sonnenschein, A.

    2008-03-01

    Purification of the 278 tons of liquid scintillator and 889 tons of buffer shielding for the Borexino solar neutrino detector is performed with a system that combines distillation, water extraction, gas stripping, and filtration. This paper describes the principles of operation, design, and construction of that purification system, and reviews the requirements and methods to achieve system cleanliness and leak-tightness.

  15. Chromatofocusing in the purification of staphylococcal enterotoxin D.

    PubMed Central

    Lei, Z; Reiser, R F; Bergdoll, M S

    1988-01-01

    A chromatofocusing procedure for the purification of staphylococcal enterotoxin D was developed. The purification included the removal of the toxic protein from culture supernatant fluids of Staphylococcus aureus 1151m by batch adsorption with CG-50 resin, chromatofocusing on Polybuffer Exchanger 94, and gel permeation chromatography on Sephacryl S-200. The purity of the staphylococcal enterotoxin D obtained was approximately 98%. PMID:3384936

  16. Chromatofocusing in the purification of staphylococcal enterotoxin D.

    PubMed

    Lei, Z; Reiser, R F; Bergdoll, M S

    1988-06-01

    A chromatofocusing procedure for the purification of staphylococcal enterotoxin D was developed. The purification included the removal of the toxic protein from culture supernatant fluids of Staphylococcus aureus 1151m by batch adsorption with CG-50 resin, chromatofocusing on Polybuffer Exchanger 94, and gel permeation chromatography on Sephacryl S-200. The purity of the staphylococcal enterotoxin D obtained was approximately 98%.

  17. Effect of Purification Procedures on DIF Analysis in IRTPRO

    ERIC Educational Resources Information Center

    Fikis, David R. J.; Oshima, T. C.

    2017-01-01

    Purification of the test has been a well-accepted procedure in enhancing the performance of tests for differential item functioning (DIF). As defined by Lord, purification requires reestimation of ability parameters after removing DIF items before conducting the final DIF analysis. IRTPRO 3 is a recently updated program for analyses in item…

  18. An Adaptable Investigative Graduate Laboratory Course for Teaching Protein Purification

    ERIC Educational Resources Information Center

    Carroll, Christopher W.; Keller, Lani C.

    2014-01-01

    This adaptable graduate laboratory course on protein purification offers students the opportunity to explore a wide range of techniques while allowing the instructor the freedom to incorporate their own personal research interests. The course design involves two sequential purification schemes performed in a single semester. The first part…

  19. An Adaptable Investigative Graduate Laboratory Course for Teaching Protein Purification

    ERIC Educational Resources Information Center

    Carroll, Christopher W.; Keller, Lani C.

    2014-01-01

    This adaptable graduate laboratory course on protein purification offers students the opportunity to explore a wide range of techniques while allowing the instructor the freedom to incorporate their own personal research interests. The course design involves two sequential purification schemes performed in a single semester. The first part…

  20. High-yield fermentation and a novel heat-precipitation purification method for hydrophobin HGFI from Grifola frondosa in Pichia pastoris.

    PubMed

    Song, Dongmin; Gao, Zhendong; Zhao, Liqiang; Wang, Xiangxiang; Xu, Haijin; Bai, Yanling; Zhang, Xiuming; Linder, Markus B; Feng, Hui; Qiao, Mingqiang

    2016-12-01

    Hydrophobins are proteins produced by filamentous fungi with high natural-surfactant activities and that can self-assemble in interfaces of air-water or solid-water to form amphiphilic membranes. Here, we reported a high-yield fermentation method for hydrophobin HGFI from Grifola frondosa in Pichia pastoris, attaining production of 300 mg/L by keeping the dissolved oxygen level at 15%-25% by turning the methanol-feeding speed. We also developed a novel HGFI-purification method enabling large-scare purification of HGFI, with >90% recovery. Additionally, we observed that hydrophobin HGFI in fermentation broth precipitated at pH < 7.0 and temperatures >90 °C. We also identified the structure and properties of proteins purified by this method through atomic force microscopy, circular dichroism, X-ray photoelectron spectroscopy, and water-contact angle measurement, which is similar to protein purification by ultrafiltration without heating treatment that enables our method to maintain native HGFI structure and properties. Furthermore, the purification method presented here can be applied to large-scale purification of other type I hydrophobins. Copyright © 2016. Published by Elsevier Inc.

  1. Ribonucleoprotein purification and characterization using RNA Mango.

    PubMed

    Panchapakesan, Shanker Shyam S; Ferguson, Matthew L; Hayden, Eric J; Chen, Xin; Hoskins, Aaron A; Unrau, Peter J

    2017-10-01

    The characterization of RNA-protein complexes (RNPs) is a difficult but increasingly important problem in modern biology. By combining the compact RNA Mango aptamer with a fluorogenic thiazole orange desthiobiotin (TO1-Dtb or TO3-Dtb) ligand, we have created an RNA tagging system that simplifies the purification and subsequent characterization of endogenous RNPs. Mango-tagged RNP complexes can be immobilized on a streptavidin solid support and recovered in their native state by the addition of free biotin. Furthermore, Mango-based RNP purification can be adapted to different scales of RNP isolation ranging from pull-down assays to the isolation of large amounts of biochemically defined cellular RNPs. We have incorporated the Mango aptamer into the S. cerevisiae U1 small nuclear RNA (snRNA), shown that the Mango-snRNA is functional in cells, and used the aptamer to pull down a U1 snRNA-associated protein. To demonstrate large-scale isolation of RNPs, we purified and characterized bacterial RNA polymerase holoenzyme (HE) in complex with a Mango-containing 6S RNA. We were able to use the combination of a red-shifted TO3-Dtb ligand and eGFP-tagged HE to follow the binding and release of the 6S RNA by two-color native gel analysis as well as by single-molecule fluorescence cross-correlation spectroscopy. Together these experiments demonstrate how the Mango aptamer in conjunction with simple derivatives of its flurophore ligands enables the purification and characterization of endogenous cellular RNPs in vitro. © 2017 Panchapakesan et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  2. Self Purification of Two Serine Endopeptidases*

    PubMed Central

    Awad, W. M.; Ochoa, Maria S.; Toomey, T. P.

    1972-01-01

    We have reported that a serine protease from Pronase, homologous with bovine chymotrypsin, is both active and stable in 6 M guanidinium chloride. The present investigation examined the possibility that this unique property might be used to permit the enzyme to engage in its own purification by cleaving companion proteins to low-molecular-weight products. Analysis with model substrates of the several specific activities that were originally present revealed that only the activity against Nα-acetyl-L-tyrosine ethyl ester was demonstrable after incubation for 100 hr in the denaturant. After a moderate loss within the first 24 hr, the remaining activity against this ester was conserved for many days thereafter. Pronase was routinely incubated for 1 week at 22° in 6 M guanidinium chloride at pH 8.0 where the esterases showed maximal activity. Analysis of the products of incubation revealed unexpectedly the presence of two serine proteases that were easily separated. After purification to homogeneity these components proved themselves to be the previously demonstrated subtilisin-like and stable chymotrypsin-like enzymes. The only amino-terminal residue of the chymotrypsin-like enzyme is isoleucine, as it is in the earlier, conventionally purified product. The migration of the single band of this enzyme during acrylamide gel electrophoresis was the same whether purified by the past or present technique. No free amino-terminal group was demonstrable in the subtilisin-like enzyme. This study presents a unique and rapid technique for isolation of these proteases, with the first reported purification to homogeneity of the subtilisin-like component. These enzymes may be useful as probes for local relaxations of conformation in substrate proteins. Furthermore, they may contribute to the preparation of enzyme-free non-protein macromolecules. Images PMID:4506775

  3. Purification of Nanoparticles by Size and Shape

    PubMed Central

    Robertson, James D.; Rizzello, Loris; Avila-Olias, Milagros; Gaitzsch, Jens; Contini, Claudia; Magoń, Monika S.; Renshaw, Stephen A.; Battaglia, Giuseppe

    2016-01-01

    Producing monodisperse nanoparticles is essential to ensure consistency in biological experiments and to enable a smooth translation into the clinic. Purification of samples into discrete sizes and shapes may not only improve sample quality, but also provide us with the tools to understand which physical properties of nanoparticles are beneficial for a drug delivery vector. In this study, using polymersomes as a model system, we explore four techniques for purifying pre-formed nanoparticles into discrete fractions based on their size, shape or density. We show that these techniques can successfully separate polymersomes into monodisperse fractions. PMID:27271538

  4. Purification of the enzyme NADPH: protochlorophyllide oxidoreductase.

    PubMed

    Beer, N S; Griffiths, W T

    1981-04-01

    A procedure for the purification of the enzyme NADPH:protochlorophyllide oxidoreductase is described. This involves fractionation of sonicated oat etioplast membranes by discontinuous-sucrose-density-gradient centrifugation, which gives membranes in which the enzyme is present at a high specific activity. The enzyme is solubilized from the membranes with Triton X-100, followed by gel filtration of the extract; enzyme activity is eluted in fractions corresponding to a mol.wt of approx. 35000. Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis of the enzyme-containing fractions from gel filtration shows two peptides, of mol.wts. approx. 35000 and 37000.

  5. Block Copolymer Membranes for Biofuel Purification

    NASA Astrophysics Data System (ADS)

    Evren Ozcam, Ali; Balsara, Nitash

    2012-02-01

    Purification of biofuels such as ethanol is a matter of considerable concern as they are produced in complex multicomponent fermentation broths. Our objective is to design pervaporation membranes for concentrating ethanol from dilute aqueous mixtures. Polystyrene-b-polydimethylsiloxane-b-polystyrene block copolymers were synthesized by anionic polymerization. The polydimethylsiloxane domains provide ethanol-transporting pathways, while the polystyrene domains provide structural integrity for the membrane. The morphology of the membranes is governed by the composition of the block copolymer while the size of the domains is governed by the molecular weight of the block copolymer. Pervaporation data as a function of these two parameters will be presented.

  6. Biotechnology Protein Expression and Purification Facility

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The purpose of the Project Scientist Core Facility is to provide purified proteins, both recombinant and natural, to the Biotechnology Science Team Project Scientists and the NRA-Structural Biology Test Investigators. Having a core facility for this purpose obviates the need for each scientist to develop the necessary expertise and equipment for molecular biology, protein expression, and protein purification. Because of this, they are able to focus their energies as well as their funding on the crystallization and structure determination of their target proteins.

  7. Biotechnology Protein Expression and Purification Facility

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The purpose of the Project Scientist Core Facility is to provide purified proteins, both recombinant and natural, to the Biotechnology Science Team Project Scientists and the NRA-Structural Biology Test Investigators. Having a core facility for this purpose obviates the need for each scientist to develop the necessary expertise and equipment for molecular biology, protein expression, and protein purification. Because of this, they are able to focus their energies as well as their funding on the crystallization and structure determination of their target proteins.

  8. Hormone purification by isoelectric focusing in space

    NASA Technical Reports Server (NTRS)

    Bier, M.

    1982-01-01

    The performance of a ground-prototype of an apparatus for recycling isoelectric focusing was evaluated in an effort to provide technology for large scale purification of peptide hormones, proteins, and other biologicals. Special emphasis was given to the effects of gravity on the function of the apparatus and to the determination of potential advantages deriveable from its use in a microgravity environment. A theoretical model of isoelectric focusing sing chemically defined buffer systems for the establishment of the pH gradients was developed. The model was transformed to a form suitable for computer simulations and was used extensively for the design of experimental buffers.

  9. Purification using high pressure molten aluminum

    NASA Astrophysics Data System (ADS)

    Sample, Vivek M.; Cassada, William A.

    A novel technique has been developed to separate eutectic forming elements using a continuous supply of high pressure molten aluminum. In this continuous process, enriched liquid in the mushy zone is selectively expelled from the solidifying mold through a permeable membrane. The fraction of expelled liquid and the level of purification attained can be controlled in real time. Applications of this technique for refining smelter grade aluminum as well as recycling aluminum scrap are being explored. Unique aspects and advantages of the process will be discussed.

  10. [Purification of {sup 67}Cu]. Progress report

    SciTech Connect

    DeNardo, S.J.

    1994-09-01

    This report documents progress made in several areas of research and describes results which have not yet been published. These areas include: Purification of {sup 67}Cu; Macrocyclic chelates for targeted therapy; Studies of biologic activation associated with molecular receptor increase and tumor response in ChL6/L6 protocol patients; Lym-1 single chain genetically engineered molecules; Analysis of molecular genetic coded messages to enhance tumor response; Human dosimetry and therapeutic human use radiopharmaceuticals; studies in phantoms; Quantitative SPECT; Preclinical studies; and Clinical studies.

  11. Purification of Nanoparticles by Size and Shape

    NASA Astrophysics Data System (ADS)

    Robertson, James D.; Rizzello, Loris; Avila-Olias, Milagros; Gaitzsch, Jens; Contini, Claudia; Magoń, Monika S.; Renshaw, Stephen A.; Battaglia, Giuseppe

    2016-06-01

    Producing monodisperse nanoparticles is essential to ensure consistency in biological experiments and to enable a smooth translation into the clinic. Purification of samples into discrete sizes and shapes may not only improve sample quality, but also provide us with the tools to understand which physical properties of nanoparticles are beneficial for a drug delivery vector. In this study, using polymersomes as a model system, we explore four techniques for purifying pre-formed nanoparticles into discrete fractions based on their size, shape or density. We show that these techniques can successfully separate polymersomes into monodisperse fractions.

  12. Biopharmaceuticals from microorganisms: from production to purification.

    PubMed

    Jozala, Angela Faustino; Geraldes, Danilo Costa; Tundisi, Louise Lacalendola; Feitosa, Valker de Araújo; Breyer, Carlos Alexandre; Cardoso, Samuel Leite; Mazzola, Priscila Gava; Oliveira-Nascimento, Laura de; Rangel-Yagui, Carlota de Oliveira; Magalhães, Pérola de Oliveira; Oliveira, Marcos Antonio de; Pessoa, Adalberto

    2016-12-01

    The use of biopharmaceuticals dates from the 19th century and within 5-10 years, up to 50% of all drugs in development will be biopharmaceuticals. In the 1980s, the biopharmaceutical industry experienced a significant growth in the production and approval of recombinant proteins such as interferons (IFN α, β, and γ) and growth hormones. The production of biopharmaceuticals, known as bioprocess, involves a wide range of techniques. In this review, we discuss the technology involved in the bioprocess and describe the available strategies and main advances in microbial fermentation and purification process to obtain biopharmaceuticals.

  13. [Isolation and purification of virus damaging sunflower].

    PubMed

    Zakusilo, A O; Didenko, L F; Kniazieva, N A; Boĭko, A L

    1994-01-01

    A procedure has been developed for purifying intact virus's isolate particles evoking yellow spot mosaic disease in sunflower. Purification of pathogen in 0.1 M sodium phosphate buffer, pH 8.0 containing 0.05 M Na3SO3 and 0.2% 2-mercaptoethanol is used. After first clarification extract was exposed to two cycles of high-speed centrifugation and fractionated in linear 10-40% (wt vol-1) sucrose density gradient. Virus was recovered from appropriate fractions after dialysis against 0.01 M Na2SO3.

  14. Air Cleaning Technologies

    PubMed Central

    2005-01-01

    to remove airborne pathogens from room air depends on several factors, including the airflow rate through the unit’s filter and the airflow patterns in the room. Tested under a variety of conditions, in-room air cleaners, including portable or ceiling mounted units with either a HEPA or a non-HEPA filter, portable units with UVGI lights only, or ceiling mounted units with combined HEPA filtration and UVGI lights, have been estimated to be between 30% and 90%, 99% and 12% and 80% effective, respectively. However, and although their effectiveness is variable, the United States Centers for Disease Control and Prevention has acknowledged in-room air cleaners as alternative technology for increasing room ventilation when this cannot be achieved by the building’s HVAC system with preference given to fixed recirculating systems over portable ones. Importantly, the use of an in-room air cleaner does not preclude either the need for health care workers and visitors to use personal protective equipment (N95 mask or equivalent) when entering AII rooms or health care facilities from meeting current regulatory requirements for airflow rates (ventilation rates) in buildings and airflow differentials for effective negative-pressure rooms. The Plasmacluster ion technology, developed in 2000, is an air purification technology. Its manufacturer, Sharp Electronics Corporation, says that it can disable airborne microorganisms through the generation of both positive and negative ions. (1) The functional unit is the hydroxyl, which is a molecule comprised of one oxygen molecule and one hydrogen atom. Plasmacluster ion air purifier uses a multilayer filter system composed of a prefilter, a carbon filter, an antibacterial filter, and a HEPA filter, combined with an ion generator to purify the air. The ion generator uses an alternating plasma discharge to split water molecules into positively and negatively charged ions. When these ions are emitted into the air, they are surrounded by

  15. An Innovative Reactor Technology to Improve Indoor Air Quality

    SciTech Connect

    Rempel, Jane

    2013-03-30

    As residential buildings achieve tighter envelopes in order to minimize energy used for space heating and cooling, accumulation of indoor air pollutants such as volatile organic compounds (VOCs), becomes a major concern causing poor air quality and increased health risks. Current VOC removal methods include sorbents, ultraviolet photocatalytic oxidation (UVPCO), and increased ventilation, but these methods do not capture or destroy all VOCs or are prohibitively expensive to implement. TIAX's objective in this program was to develop a new VOC removal technology for residential buildings. This novel air purification technology is based on an innovative reactor and light source design along with UVPCO properties of the chosen catalyst to purify indoor air and enhance indoor air quality (IAQ). During the program we designed, fabricated and tested a prototype air purifier to demonstrate its feasibility and effectiveness. We also measured kinetics of VOC destruction on photocatalysts, providing deep insight into reactor design.

  16. Native Purification and Analysis of Long RNAs

    PubMed Central

    Chillón, Isabel; Marcia, Marco; Legiewicz, Michal; Liu, Fei; Somarowthu, Srinivas; Pyle, Anna Marie

    2015-01-01

    The purification and analysis of long noncoding RNAs (lncRNAs) in vitro is a challenge, particularly if one wants to preserve elements of functional structure. Here, we describe a method for purifying lncRNAs that preserves the cotranscriptionally derived structure. The protocol avoids the misfolding that can occur during denaturation–renaturation protocols, thus facilitating the folding of long RNAs to a native-like state. This method is simple and does not require addition of tags to the RNA or the use of affinity columns. LncRNAs purified using this type of native purification protocol are amenable to biochemical and biophysical analysis. Here, we describe how to study lncRNA global compaction in the presence of divalent ions at equilibrium using sedimentation velocity analytical ultracentrifugation and analytical size-exclusion chromatography as well as how to use these uniform RNA species to determine robust lncRNA secondary structure maps by chemical probing techniques like selective 2′-hydroxyl acylation analyzed by primer extension and dimethyl sulfate probing. PMID:26068736

  17. Online Oxide Contamination Measurement and Purification Demonstration

    NASA Technical Reports Server (NTRS)

    Bradley, D. E.; Godfroy, T. J.; Webster, K. L.; Garber, A. E.; Polzin, K. A.; Childers, D. J.

    2011-01-01

    Liquid metal sodium-potassium (NaK) has advantageous thermodynamic properties indicating its use as a fission reactor coolant for a surface (lunar, martian) power system. A major area of concern for fission reactor cooling systems is system corrosion due to oxygen contaminants at the high operating temperatures experienced. A small-scale, approximately 4-L capacity, simulated fission reactor cooling system employing NaK as a coolant was fabricated and tested with the goal of demonstrating a noninvasive oxygen detection and purification system. In order to generate prototypical conditions in the simulated cooling system, several system components were designed, fabricated, and tested. These major components were a fully-sealed, magnetically-coupled mechanical NaK pump, a graphite element heated reservoir, a plugging indicator system, and a cold trap. All system components were successfully demonstrated at a maximum system flow rate of approximately 150 cc/s at temperatures up to 550 C. Coolant purification was accomplished using a cold trap before and after plugging operations which showed a relative reduction in oxygen content.

  18. Preliminary Hazards Assessment: Iron disulfide purification system

    SciTech Connect

    1991-07-30

    A process for the purification (washing) of iron disulfide (FeS{sub 2}) powder is conducted in the Northeast corner (Area 353) of the main plant building (Building 100). This location is about 130 feet from the fenced boundary of the Partnership School/Child Development Center. In the first steps of the process, raw iron disulfide powder is ground and separated by particle size. The ground and sized powder is then purified in a three-step acid washing process using both hydrochloric acid (HCI) and hydrofluoric (HF) acid. The iron disulfide process is an intermittent batch process conducted four to eight times a year. This study is a Preliminary Hazards Assessment (PHA) to assess the hazards associated with the iron disulfide process. This is a preliminary study and will be used to determine if additional safety analysis is necessary. The scope of the PHA includes assessment of the process steps of grinding, size classification, and purification. The purpose is to identify major hazards and determine if the current and newly added safeguards are adequate for operation. The PHA also lists recommendations for additional safety features that should be added to reduce the risks of operation.

  19. Air Policing

    DTIC Science & Technology

    2009-05-01

    Iraq. To provide a background for understanding why Britain commenced the policy of air policing, this paper begins with a review of contemporary...7 Omissi, Air Power, XV. 8 policing actions or the pushing home of advantages gained by the air.” Within the context of this paper , the...control operations, and therefore within the context of this paper , the term coercive airpower refers to the threat of harming a population or the threat

  20. Method for the purification of noble gases, nitrogen and hydrogen

    DOEpatents

    Baker, J.D.; Meikrantz, D.H.; Tuggle, D.G.

    1997-09-23

    A method and apparatus are disclosed for the purification and collection of hydrogen isotopes in a flowing inert gaseous mixture containing impurities, wherein metal alloy getters having the capability of sorbing non-hydrogen impurities such as oxygen, carbon dioxide, carbon monoxide, methane, ammonia, nitrogen and water vapor are utilized to purify the gaseous mixture of impurities. After purification hydrogen isotopes may be more efficiently collected. A plurality of parallel process lines utilizing metal getter alloys can be used to provide for the continuous purification and collection of the hydrogen isotopes. 15 figs.

  1. Nylon wool purification alters the activation of T cells.

    PubMed

    Wohler, Jillian E; Barnum, Scott R

    2009-02-01

    Purification of lymphocytes, particularly T cells, is commonly performed using nylon wool. This enrichment method selectively retains B cells and some myeloid cells allowing a significantly more pure T cell population to flow through a nylon wool column. T cells purified in this fashion are assumed to be unaltered and functionally naïve, however some studies have suggested aberrant in vitro T cell responses after nylon wool treatment. We found that nylon wool purification significantly altered T cell proliferation, expression of activation markers and production of cytokines. Our results suggest that nylon wool treatment modifies T cell activation responses and that caution should be used when choosing this purification method.

  2. Polyether sulfone/hydroxyapatite mixed matrix membranes for protein purification

    NASA Astrophysics Data System (ADS)

    Sun, Junfen; Wu, Lishun

    2014-07-01

    This work proposes a novel approach for protein purification from solution using mixed matrix membranes (MMMs) comprising of hydroxyapatite (HAP) inside polyether sulfone (PES) matrix. The influence of HAP particle loading on membrane morphology is studied. The MMMs are further characterized concerning permeability and adsorption capacity. The MMMs show purification of protein via both diffusion as well as adsorption, and show the potential of using MMMs for improvements in protein purification techniques. The bovine serum albumin (BSA) was used as a model protein. The properties and structures of MMMs prepared by immersion phase separation process were characterized by pure water flux, BSA adsorption and scanning electron microscopy (SEM).

  3. Method for the purification of noble gases, nitrogen and hydrogen

    DOEpatents

    Baker, John D.; Meikrantz, David H.; Tuggle, Dale G.

    1997-01-01

    A method and apparatus for the purification and collection of hydrogen isotopes in a flowing inert gaseous mixture containing impurities, wherein metal alloy getters having the capability of sorbing non-hydrogen impurities such as oxygen, carbon dioxide, carbon monoxide, methane, ammonia, nitrogen and water vapor are utilized to purify the gaseous mixture of impurities. After purification hydrogen isotopes may be more efficiently collected. A plurality of parallel process lines utilizing metal getter alloys can be used to provide for the continuous purification and collection of the hydrogen isotopes.

  4. Purification of helium for chromatographic analysis by electrical discharge

    SciTech Connect

    Bondarenko, I.V.; Budovich, V.L.; Myagkov, E.A.; Okhotnikov, B.P.

    1986-02-01

    In order to apply gas discharge purification of helium in chromotographic analysis, the authors have carried out the separation process in the present work at a pressure above the atmospheric pressure. They then carry out the purification in an arc discharge, because it is difficult to achieve a stationary glow discharge at atmospheric pressure. Cylinder discharge chambers were used in the experiments, made of stainless steel with Teflon flanges. A decrease in the nitrogen content by a factor of 7-10 has been obtained in the experiments. The proposed method can be used for the purification of helium from cylinders in different variants of chromatographic analysis.

  5. Air Pollution.

    ERIC Educational Resources Information Center

    Fox, Donald L.

    1989-01-01

    Materials related to air pollution are reviewed for the period January 1987, to October 1988. The topics are pollution monitoring, air pollution, and environmental chemistry. The organization consists of two major analytical divisions: (1) gaseous methods; and (2) aerosol and particulate methods. (MVL)

  6. Air Pollution.

    EPA Science Inventory

    Air quality is affected by many types of pollutants that are emitted from various sources, including stationary and mobile. These sources release both criteria and hazardous air pollutants, which cause health effects, ecological harm, and material damage. They are generally categ...

  7. Air Pollution.

    ERIC Educational Resources Information Center

    Fox, Donald L.

    1989-01-01

    Materials related to air pollution are reviewed for the period January 1987, to October 1988. The topics are pollution monitoring, air pollution, and environmental chemistry. The organization consists of two major analytical divisions: (1) gaseous methods; and (2) aerosol and particulate methods. (MVL)

  8. Air Pollution.

    EPA Science Inventory

    Air quality is affected by many types of pollutants that are emitted from various sources, including stationary and mobile. These sources release both criteria and hazardous air pollutants, which cause health effects, ecological harm, and material damage. They are generally categ...

  9. Air transport

    NASA Technical Reports Server (NTRS)

    Page, F Handley

    1924-01-01

    I purpose (sic) in this paper to deal with the development in air transport which has taken place since civil aviation between England and the Continent first started at the end of August 1919. A great deal of attention has been paid in the press to air services of the future, to the detriment of the consideration of results obtained up to the present.

  10. Purification of a single-photon nonlinearity

    PubMed Central

    Snijders, H.; Frey, J. A.; Norman, J.; Bakker, M. P.; Langman, E. C.; Gossard, A.; Bowers, J. E.; van Exter, M. P.; Bouwmeester, D.; Löffler, W.

    2016-01-01

    Single photon nonlinearities based on a semiconductor quantum dot in an optical microcavity are a promising candidate for integrated optical quantum information processing nodes. In practice, however, the finite quantum dot lifetime and cavity-quantum dot coupling lead to reduced fidelity. Here we show that, with a nearly polarization degenerate microcavity in the weak coupling regime, polarization pre- and postselection can be used to restore high fidelity. The two orthogonally polarized transmission amplitudes interfere at the output polarizer; for special polarization angles, which depend only on the device cooperativity, this enables cancellation of light that did not interact with the quantum dot. With this, we can transform incident coherent light into a stream of strongly correlated photons with a second-order correlation value up to 40, larger than previous experimental results, even in the strong-coupling regime. This purification technique might also be useful to improve the fidelity of quantum dot based logic gates. PMID:27573361

  11. Concentration and purification of plutonium or thorium

    DOEpatents

    Hayden, John A.; Plock, Carl E.

    1976-01-01

    In this invention a first solution obtained from such as a plutonium/thorium purification process or the like, containing plutonium (Pu) and/or thorium (Th) in such as a low nitric acid (HNO.sub.3) concentration may have the Pu and/or Th separated and concentrated by passing an electrical current from a first solution having disposed therein an anode to a second solution having disposed therein a cathode and separated from the first solution by a cation permeable membrane, the Pu or Th cation permeating the cation membrane and forming an anionic complex within the second solution, and electrical current passage affecting the complex formed to permeate an anion membrane separating the second solution from an adjoining third solution containing disposed therein an anode, thereby effecting separation and concentration of the Pu and/or Th in the third solution.

  12. Systems, compositions, and methods for fluid purification

    DOEpatents

    Ho, W.S. Winston; Verweij, Hendrik; Shqau, Krenar; Ramasubranian, Kartik

    2015-12-22

    Disclosed herein are membranes comprising a substrate, a support layer, and a selective layer. In some embodiments the membrane may further comprise a permeable layer. Methods of forming membranes are also disclosed comprising forming a support layer on a substrate, removing adsorbed species from the support layer, preparing a solution containing inorganic materials of a selective layer, contacting the support layer with the solution, drying the membrane, and exposing the membrane to rapid thermal processing. Also disclosed are methods of fluid purification comprising providing a membrane having a feed side and a permeable side, passing a fluid mixture across the feed side of the membrane, providing a driving force for transmembrane permeation, removing from the permeate side a permeate stream enriched in a purified fluid, and withdrawing from the feed side a fluid that is depleted in a purified fluid.

  13. Nanocellulose-Based Materials for Water Purification

    PubMed Central

    Voisin, Hugo; Bergström, Lennart; Liu, Peng; Mathew, Aji P.

    2017-01-01

    Nanocellulose is a renewable material that combines a high surface area with high strength, chemical inertness, and versatile surface chemistry. In this review, we will briefly describe how nanocellulose is produced, and present—in particular, how nanocellulose and its surface modified versions affects the adsorption behavior of important water pollutants, e.g., heavy metal species, dyes, microbes, and organic molecules. The processing of nanocellulose-based membranes and filters for water purification will be described in detail, and the uptake capacity, selectivity, and removal efficiency will also be discussed. The processing and performance of nanocellulose-based membranes, which combine a high removal efficiency with anti-fouling properties, will be highlighted. PMID:28336891

  14. Biomimetic affinity ligands for protein purification.

    PubMed

    Sousa, Isabel T; Taipa, M Angela

    2014-01-01

    The development of sophisticated molecular modeling software and new bioinformatic tools, as well as the emergence of data banks containing detailed information about a huge number of proteins, enabled the de novo intelligent design of synthetic affinity ligands. Such synthetic compounds can be tailored to mimic natural biological recognition motifs or to interact with key surface-exposed residues on target proteins and are designated as "biomimetic ligands." A well-established methodology for generating biomimetic or synthetic affinity ligands integrates rational design with combinatorial solid-phase synthesis and screening, using the triazine scaffold and analogues of amino acids side chains to create molecular diversity.Triazine-based synthetic ligands are nontoxic, low-cost, highly stable compounds that can replace advantageously natural biological ligands in the purification of proteins by affinity-based methodologies.

  15. Purification of Highly Contaminated Magnesium Melt

    NASA Astrophysics Data System (ADS)

    Moon, Byoung-Gi; You, Bong-Sun; Koh, Ki-Ho

    The steering wheel core is chosen as the first target for the development of a purification technology for highly contaminated magnesium melt, because it contains abundant foreign matter such as polyurethane, copper electrodes, and steel inserts, which have high potential to form non-metallic inclusions and to deteriorate the corrosion resistance of recycled alloys. Various melt treatment technologies have been investigated for refining AM50 magnesium alloy contaminated with polyurethane. The NMI content in magnesium alloy scrap contaminated with polyurethane was effectively reduced by a sequential refining process consisting of filtration, fluxing, and gas bubbling treatments. The filtration step reduced most large inclusions such as carbon residues from the decomposed polyurethane. The subsequent fluxing and gas bubbling treatments effectively removed the small inclusions such as carbonates and oxides.

  16. Overview of Albumin and Its Purification Methods

    PubMed Central

    Raoufinia, Ramin; Mota, Ali; Keyhanvar, Neda; Safari, Fatemeh; Shamekhi, Sara; Abdolalizadeh, Jalal

    2016-01-01

    As the most frequent plasma protein, albumin constitutes more than 50% of the serum proteins in healthy individuals. It has a key role in oncotic pressure maintenance and it is known as a versatile protein carrier for transportation of various endogenous and exogenous ligands. Reduced amounts of albumin in the body will lead to different kinds of diseases such as hypovolemia and hypoproteinemia. It also has various indications in shocks, burns, cardiopulmonary bypass, acute liver failure and etc. Further applications in research consist of cell culture supplement, drug delivery carrier and protein/drug stabilizer. So, the demand for albumin increased annually worldwide. Due to different applications of albumin, many efforts have been accomplished to achieve albumin during a long period of time. In this review, an overview of serum albumin and different purification methods are summarized. PMID:28101456

  17. Purification and characterization of the Oligosaccharyl transferase

    SciTech Connect

    Kapoor, T.M.

    1990-11-01

    Oligosaccharyl transferase was characterized to be a glycoprotein with at least one saccharide unit that had a D-manno or D- glucopyranose configuration with unmodified hydroxy groups at C-3, C-4 and C-6, using a Concanavalin A affinity column. This afforded a 100 fold increase in the transferase purity in the solubilized microsomal sample and also removed over 90% of the microsomal proteins (the cytosolic ones being removed before solubilization). The detergent, N,N-Dimethyldodecylamine N-oxide (LDAO) was used for solubilization and it yielded a system compatible with the assay and the purification steps. An efficient method for detergent extraction without dilution of sample or protein precipitation was also developed.

  18. A catalytic plasma exhaust purification system

    SciTech Connect

    Penzhorn, R.D.; Rodriguez, R.; Gluglia, M.; Gunther, K.; Yoshida, H.; Konishi, S.

    1988-09-01

    For the plasma exhaust clean-up of a fusion reactor a process concept based on the hydrogen isotope purification through palladium/silver alloy permeators combined with selective catalytic reaction steps is proposed, which avoids intermediate conversion of impurities into water. To recover tritium from tritiated impurities ammonia is decomposed into the elements inside the permeators; water is reduced catalytically by carbon monoxide into carbon dioxide and hydrogen; and hydrocarbons are cracked into carbon and hydrogen on a nickel catalyst. Experimental results on the reactivity, consumption and regeneration of the catalysts are given. The permeation rate of hydrogen through palladium/silver alloy was found to be largely independent of the impurities CO, CO/sub 2/, H/sub 2/O and CH/sub 4/. Technological requirements in view of NET are discussed.

  19. Silver nanocluster catalytic microreactors for water purification

    NASA Astrophysics Data System (ADS)

    Da Silva, B.; Habibi, M.; Ognier, S.; Schelcher, G.; Mostafavi-Amjad, J.; Khalesifard, H. R. M.; Tatoulian, M.; Bonn, D.

    2016-07-01

    A new method for the elaboration of a novel type of catalytic microsystem with a high specific area catalyst is developed. A silver nanocluster catalytic microreactor was elaborated by doping a soda-lime glass with a silver salt. By applying a high power laser beam to the glass, silver nanoclusters are obtained at one of the surfaces which were characterized by BET measurements and AFM. A microfluidic chip was obtained by sealing the silver coated glass with a NOA 81 microchannel. The catalytic activity of the silver nanoclusters was then tested for the efficiency of water purification by using catalytic ozonation to oxidize an organic pollutant. The silver nanoclusters were found to be very stable in the microreactor and efficiently oxidized the pollutant, in spite of the very short residence times in the microchannel. This opens the way to study catalytic reactions in microchannels without the need of introducing the catalyst as a powder or manufacturing complex packed bed microreactors.

  20. Semiconductor grade, solar silicon purification project

    NASA Technical Reports Server (NTRS)

    Ingle, W. M.; Chaney, R.; Thompson, S.

    1977-01-01

    The potential for a three step SiF2 polymer transport purification process was examined. The process involves reacting low cost mg silicon with SiF4 to yield SiF2 gas which is condensed to form polymeric (SiF2)x. The polymer is then heated above 400 C to yield Si, SiF4 and higher Si sub n F sub 2n+2 homologues. This report presents and discusses continuing progress on (1) observations on (SiF2)x polymer formation and depolymerization on the small coil, (2) mass balance studies, (3) partial pressures of SiF2 and SiF4, (4) AlF3 mass spectral studies, and (5) material analysis studies.

  1. Nanocellulose-Based Materials for Water Purification.

    PubMed

    Voisin, Hugo; Bergström, Lennart; Liu, Peng; Mathew, Aji P

    2017-03-05

    Nanocellulose is a renewable material that combines a high surface area with high strength, chemical inertness, and versatile surface chemistry. In this review, we will briefly describe how nanocellulose is produced, and present-in particular, how nanocellulose and its surface modified versions affects the adsorption behavior of important water pollutants, e.g., heavy metal species, dyes, microbes, and organic molecules. The processing of nanocellulose-based membranes and filters for water purification will be described in detail, and the uptake capacity, selectivity, and removal efficiency will also be discussed. The processing and performance of nanocellulose-based membranes, which combine a high removal efficiency with anti-fouling properties, will be highlighted.

  2. Purification of a single-photon nonlinearity

    NASA Astrophysics Data System (ADS)

    Snijders, H.; Frey, J. A.; Norman, J.; Bakker, M. P.; Langman, E. C.; Gossard, A.; Bowers, J. E.; van Exter, M. P.; Bouwmeester, D.; Löffler, W.

    2016-08-01

    Single photon nonlinearities based on a semiconductor quantum dot in an optical microcavity are a promising candidate for integrated optical quantum information processing nodes. In practice, however, the finite quantum dot lifetime and cavity-quantum dot coupling lead to reduced fidelity. Here we show that, with a nearly polarization degenerate microcavity in the weak coupling regime, polarization pre- and postselection can be used to restore high fidelity. The two orthogonally polarized transmission amplitudes interfere at the output polarizer; for special polarization angles, which depend only on the device cooperativity, this enables cancellation of light that did not interact with the quantum dot. With this, we can transform incident coherent light into a stream of strongly correlated photons with a second-order correlation value up to 40, larger than previous experimental results, even in the strong-coupling regime. This purification technique might also be useful to improve the fidelity of quantum dot based logic gates.

  3. Purification of biomaterials by phase partitioning

    NASA Technical Reports Server (NTRS)

    Harris, J. M.

    1984-01-01

    A technique which is particularly suited to microgravity environments and which is potentially more powerful than electrophoresis is phase partitioning. Phase partitioning is purification by partitioning between the two immiscible aqueous layers formed by solution of the polymers poly(ethylene glycol) and dextran in water. This technique proved to be very useful for separations in one-g but is limited for cells because the cells are more dense than the phase solutions thus tend to sediment to the bottom of the container before reaching equilibrium with the preferred phase. There are three phases to work in this area: synthesis of new polymers for affinity phase partitioning; development of automated apparatus for ground-based separations; and design of apparatus for performing simple phase partitioning space experiments, including examination of mechanisms for separating phases in the absence of gravity.

  4. C1 inhibitor: quantification and purification.

    PubMed

    Varga, Lilian; Dobó, József

    2014-01-01

    C1 inhibitor is a multipotent serpin capable of inhibiting the classical and the lectin pathways of complement, the fibrinolytic system, and contact/kinin system of coagulation. Deficiency of C1 inhibitor manifest as hereditary angioedema (HAE), an autosomal dominant hereditary disease. Measuring the C1 inhibitor level is of vital importance for the diagnosis of HAE and also for monitoring patients receiving C1 inhibitor for therapy. Determination of the antigenic C1 inhibitor level by the radial immunodiffusion (RID) technique is described in detail in this chapter. The presented purification method of plasma C1 inhibitor is primarily based on its high carbohydrate content and its affinity to the lectin jacalin.

  5. Blood purification in toxicology: nephrology's ugly duckling.

    PubMed

    Ghannoum, Marc; Nolin, Thomas D; Lavergne, Valery; Hoffman, Robert S

    2011-05-01

    Contrary to popular opinion, application of extracorporeal therapies for poisonings predates their use for ESRD. Despite this observation, the science of blood purification in toxicology remains desperately stagnant today. In fact, much of our current knowledge is derived from George Schreiner's 1958 review. Original publications are almost exclusively composed of case reports and case series, from which good inference is impossible. Until randomized controlled trials become available, the medical community would be well served by a group mandated to systematically review available literature, extract relevant information, provide recommendations based on current evidence, and propose research initiatives. The EXtracorporeal TReatments In Poisoning workgroup, formed by several international experts in different medical fields and represented by over 20 societies, now has this mission.

  6. Purification of RNA from milk whey.

    PubMed

    Izumi, Hirohisa; Kosaka, Nobuyoshi; Shimizu, Takashi; Sekine, Kazunori; Ochiya, Takahiro; Takase, Mitsunori

    2013-01-01

    MicroRNAs (miRNAs) are small regulatory RNA molecules that modulate specific target mRNAs and play very important roles in physiological processes. They were recently detected in body fluids such as blood, urine, saliva, and milk. These body fluid miRNAs have been studied thoroughly as potential diagnostic biomarkers. However, there have been few studies of milk miRNAs, and their roles are not clearly understood. Milk is the only nutritional source for newborn infants, and bovine milk is used widely as a dairy product. Thus, it is important to study milk miRNAs. In general, body fluid RNA concentrations are extremely low and of diverse existence types. In this chapter, we compare two silica membrane column-based RNA purification kits, and also compare RNA obtained directly from whey with that isolated from whey-derived exosomes.

  7. Purification of biomaterials by phase partitioning

    NASA Technical Reports Server (NTRS)

    Harris, J. M.

    1984-01-01

    A technique which is particularly suited to microgravity environments and which is potentially more powerful than electrophoresis is phase partitioning. Phase partitioning is purification by partitioning between the two immiscible aqueous layers formed by solution of the polymers poly(ethylene glycol) and dextran in water. This technique proved to be very useful for separations in one-g but is limited for cells because the cells are more dense than the phase solutions thus tend to sediment to the bottom of the container before reaching equilibrium with the preferred phase. There are three phases to work in this area: synthesis of new polymers for affinity phase partitioning; development of automated apparatus for ground-based separations; and design of apparatus for performing simple phase partitioning space experiments, including examination of mechanisms for separating phases in the absence of gravity.

  8. Helium recovery and purification at CHMFL

    NASA Astrophysics Data System (ADS)

    Li, J.; Meng, Q.; Ouyang, Z.; Shi, L.; Ai, X.; Chen, X.

    2017-02-01

    Currently, rising demand and declining reserves of helium have led to dramatic increases in the helium price. The High Magnetic Field Laboratory of Chinese Academy of Sciences (CHMFL) has made efforts since its foundation to increase the percentage of helium recovered. The piping network connects all the helium experimental facilities to the recovery system, and even exhaust ports of pressure relief valves and vacuum pumps are also connected. In each year, about 30,000 cubic meters helium gas is recovered. The recovery gas is purified, liquefied and supplied to the users again. This paper will provide details about the helium recovery and purification system at CHMFL, including system flowchart, components, problems and solutions.

  9. Cephalopod alcohol dehydrogenase: purification and enzymatic characterization.

    PubMed

    Rosario Fernández, M; Jörnvall, H; Moreno, A; Kaiser, R; Parés, X

    1993-08-16

    Octopus, squid and cuttle-fish organs were examined for alcohol dehydrogenase activity. Only one form was detectable, with properties typical of mammalian class III alcohol dehydrogenase. The corresponding protein was purified from octopus and enzymatically characterized. Ion-exchange and affinity chromatography produced a pure protein in excellent yield (73%) after 1600-fold purification. Enzymatic parameters with several substrates were similar to those for the human class III alcohol dehydrogenase, demonstrating a largely conserved function of the enzyme through wide lines of divergence covering vertebrates, cephalopods and bacteria. The results establish the universal occurrence of class III alcohol dehydrogenase and its strictly conserved functional properties in separate living forms. The absence of other alcohol dehydrogenases in cephalopods is compatible with the emergence of the ethanol-active class I type at a later stage, in lineages leading to vertebrates.

  10. Purification of large liquid scintillators for Borexino

    SciTech Connect

    Benziger, J.B.; Calaprice, F.P.; Vogelaar, R.B.

    1993-10-01

    Distillation extraction and crystallization have been used on scintillator mixtures for solar neutrino physics to remove cosmo- genically produced impurities ({sup 7}Be) and naturally occurring impurities ({sup 238}U, {sup 232}Th, and {sup 40}K), and to improve the optical transmission. Distillation was effective at removing {sup 7}Be and other impurities from aromatic solvents (p-xylene and pseudocumene) used as scintillator solvents. Distillation also provided the greatest improvement in the optical clarity of the solvents. Commercially available fluors (PPO and PMP) have high levels of potassium, far in excess of those tolerable for Borexino. Extraction techniques have been found to be effective at removing radioactive impurities, particularly potassium, from the fluors. An overall strategy for on-line purification of the scintillator for Borexino will be presented.

  11. (Hyper)thermophilic enzymes: production and purification.

    PubMed

    Falcicchio, Pierpaolo; Levisson, Mark; Kengen, Servé W M; Koutsopoulos, Sotirios

    2014-01-01

    The discovery of thermophilic and hyperthermophilic microorganisms, thriving at environmental temperatures near or above 100 °C, has revolutionized our ideas about the upper temperature limit at which life can exist. The characterization of (hyper)thermostable proteins has broadened our understanding and presented new opportunities for solving one of the most challenging problems in biophysics: how is structural stability and biological function maintained at high temperatures where "normal" proteins undergo dramatic structural changes? In our laboratory we have purified and studied many thermostable and hyperthermostable proteins in an attempt to determine the molecular basis of heat stability. Here, we present methods to express such proteins and enzymes in E. coli and provide a general protocol for overproduction and purification. The ability to produce enzymes that retain their stability and activity at elevated temperatures creates exciting opportunities for a wide range of biocatalytic applications.

  12. Purification and Properties of Neurospora crassa Laccase

    PubMed Central

    Froehner, Stanley C.; Eriksson, Karl-Erik

    1974-01-01

    Extracellular Neurospora laccase (p-diphenol:oxygen oxidoreductase; EC 1.10.3.2) has been purified to apparent homogeneity by classical purification techniques. The enzyme, which consists of mainly one form, has a molecular weight of 64,800 and contains 11% carbohydrate. The ultraviolet, visible, and electron paramagnetic resonance spectra indicate that both type I and type II copper are present, as described for the Polyporus versicolor enzyme. With the exception of phloroglucinol, only para- and ortho-diphenols serve as effective substrates for the enzyme. Like the extracellular form, intracellular laccase is a glycoprotein as shown by its ability to bind to Concanavalin A Sepharose. Other studies, including gel filtration and ion-exchange chromatography, revealed no differences between the intracellular and extracellular enzymes, suggesting that intracellular laccase is destined for excretion by the cell. Images PMID:4278681

  13. Submersible purification system for radioactive water

    DOEpatents

    Abbott, Michael L.; Lewis, Donald R.

    1989-01-01

    A portable, submersible water purification system for use in a pool of water containing radioactive contamination includes a prefilter for filtering particulates from the water. A resin bed is then provided for removal of remaining dissolved, particulate, organic, and colloidal impurities from the prefiltered water. A sterilizer then sterilizes the water. The prefilter and resin bed are suitably contained and are submerged in the pool. The sterilizer is water tight and located at the surface of the pool. The water is circulated from the pool through the prefilter, resin bed, and sterilizer by suitable pump or the like. In the preferred embodiment, the resin bed is contained within a tank which stands on the bottom of the pool and to which a base mounting the prefilter and pump is attached. An inlet for the pump is provided adjacent the bottom of the pool, while the sterilizer and outlet for the system is located adjacent the top of the pool.

  14. Staphylococcal micrococcins. II. Isolation, purification and identification.

    PubMed

    Breiter, J; Metz, H; Grigo, J

    1975-08-01

    Seven strains belonging to the Micrococcaceae family and excreting substances with antibiotic activity, were grown in submerged cultures on technical scale for isolation, purification and identification of biologically active compounds. Two basic substances were isolated and classified to the micrococcin antibiotics family. The naturally occurring mixture of micrococcin M1 and M3 was called micrococcin M. This antibiotic has the formula C48H50O11N12S6 and a molecular weight of about 1160, melting point 221--224 degrees C, and optical rotation [a]20/D = + 66.6. Other antibiotically active substances produced by seven investigated strains were identified as micrococcin M or as separate compounds. Comparison with previously described micrococcin and micrococcin P has been made.

  15. Hydrogen Purification Using Natural Zeolite Membranes

    NASA Technical Reports Server (NTRS)

    DelValle, William

    2003-01-01

    The School of Science at Universidad del Turabo (UT) have a long-lasting investigation plan to study the hydrogen cleaning and purification technologies. We proposed a research project for the synthesis, phase analysis and porosity characterization of zeolite based ceramic perm-selective membranes for hydrogen cleaning to support NASA's commitment to achieving a broad-based research capability focusing on aerospace-related issues. The present study will focus on technology transfer by utilizing inorganic membranes for production of ultra-clean hydrogen for application in combustion. We tested three different natural zeolite membranes (different particle size at different temperatures and time of exposure). Our results show that the membranes exposured at 900 C for 1Hr has the most higher permeation capacity, indicated that our zeolite membranes has the capacity to permeate hydrogen.

  16. Poliovirus: Generation, Quantification, Propagation, Purification, and Storage

    PubMed Central

    Burrill, Cecily P.; Strings, Vanessa R.; Andino, Raul

    2016-01-01

    Poliovirus (PV) is the prototypical picornavirus. It is a non-enveloped RNA virus with a small (~7.5 kb) genome of positive polarity. It has long served as a model to study RNA virus biology, pathogenesis, and evolution. cDNA clones of several strains are available, and infectious virus can be produced by the transfection of in vitro transcribed viral genomes into an appropriate host cell. PV infects many human and non-human primate cell lines including HeLa and HeLa S3 cells, and can grow to high titer in culture. Protocols for the production, propagation, quantification, and purification of PV are presented. A separate chapter concerning the generation and characterization of PV mutants will also be presented. PMID:23686830

  17. Protein purification using PDZ affinity chromatography.

    PubMed

    Walkup, Ward G; Kennedy, Mary B

    2015-04-01

    PDZ domains function in nature as protein-binding domains within scaffold and membrane-associated proteins. They comprise approximately 90 residues and undergo specific, high-affinity interactions with complementary C-terminal peptide sequences, other PDZ domains, and/or phospholipids. We have previously shown that the specific, strong interactions of PDZ domains with their ligands make them well suited for use in affinity chromatography. This unit provides protocols for the PDZ affinity chromatography procedure that are applicable for the purification of proteins that contain PDZ domains or PDZ domain-binding ligands, either naturally or introduced by genetic engineering. We detail the preparation of affinity resins composed of PDZ domains or PDZ domain peptide ligands coupled to solid supports. These resins can be used to purify proteins containing endogenous or genetically introduced PDZ domains or ligands, eluting the proteins with free PDZ domain peptide ligands.

  18. PURIFICATION OF IRIDIUM BY ELECTRON BEAM MELTING

    SciTech Connect

    Ohriner, Evan Keith

    2008-01-01

    The purification of iridium metal by electron beam melting has been characterized for 48 impurity elements. Chemical analysis was performed by glow discharge mass spectrographic (GDMS) analysis for all elements except carbon, which was analyzed by combustion. The average levels of individual elemental impurities in the starting powder varied from 37 g/g to 0.02 g/g. The impurity elements Li, Na, Mg, P, S, Cl, K, Ca, Mn, Co, Ni, Cu, Zn, As, Pd, Ag, Cd, Sn, Sb, Te, Ba, Ce, Tl, Pb, and Bi were not detectable following the purification. No significant change in concentration of the elements Ti, V, Zr, Nb, Mo, and Re was found. The elements B, C, Al, Si, Cr, Fe, Ru, Rh, and Pt were partially removed by vaporization during electron beam melting. Langmuir's equation for ideal vaporization into a vacuum was used to calculate for each impurity element the expected ratio of impurity content after melting to that before melting. Equilibrium vapor pressures were calculated using Henry's law, with activity coefficients obtained from published data for the elements Fe, Ti, and Pt. Activity coefficients were estimated from enthalpy data for Al, Si, V, Cr, Mn, Co, Ni, Zr, Nb, Mo, and Hf and an ideal solution model was used for the remaining elements. The melt temperature was determined from measured iridium weight loss. Excellent agreement was found between measured and calculated impurity ratios for all impurity elements. The results are consistent with some localized heating of the melt pool due to rastering of the electron beam, with an average vaporization temperature of 3100 K as compared to a temperature of 2965 K calculated for uniform heating of the melt pool. The results are also consistent with ideal mixing in the melt pool.

  19. Enzymatic processes for the purification of trehalose.

    PubMed

    Wu, Tsung-Ta; Lin, Sung-Chyr; Shaw, Je-Fu

    2013-01-01

    A dual-enzyme process aiming at facilitating the purification of trehalose from maltose is reported in this study. Enzymatic conversion of maltose to trehalose usually leads to the presence of significant amount of glucose, by-product of the reaction, and unreacted maltose. To facilitate the separation of trehalose from glucose and unreacted maltose, sequential conversion of maltose to glucose and glucose to gluconic acid under the catalysis of glucoamylase and glucose oxidase, respectively, is studied. This study focuses on the hydrolysis of maltose with immobilized glucoamylase on Eupergit® C and CM Sepharose. CM Sepharose exhibited a higher protein adsorption capacity, 49.35 ± 1.43 mg/g, and was thus selected as carrier for the immobilization of glucoamylase. The optimal reaction temperature and reaction pH of the immobilized glucoamylase for maltose hydrolysis were identified as 40°C and 4.0, respectively. Under such conditions, the unreacted maltose in the product stream of trehalose synthase-catalyzed reaction was completely converted to glucose within 35 min, without detectable trehalose degradation. The conversion of maltose to glucose could be maintained at 0.92 even after 80 cycles in repeated-batch operations. It was also demonstrated that glucose thus generated could be readily oxidized into gluconic acid, which can be easily separated from trehalose. We thus believe the proposed process of maltose hydrolysis with immobilized glucoamylase, in conjunction with trehalose synthase-catalyzed isomerization and glucose oxidase-catalyzed oxidation, is promising for the production and purification of trehalose on industrial scales.

  20. A RAPID DNA EXTRACTION METHOD FOR PCR IDENTIFICATION OF FUNGAL INDOOR AIR CONTAMINANTS

    EPA Science Inventory

    Following air sampling, fungal DNA needs to be extracted and purified to a state suitable for laboratory use. Our laboratory has developed a simple method of extraction and purification of fungal DNA appropriate for enzymatic manipulation and polymerase chain reaction (PCR) appli...

  1. A RAPID DNA EXTRACTION METHOD FOR PCR IDENTIFICATION OF FUNGAL INDOOR AIR CONTAMINANTS

    EPA Science Inventory

    Following air sampling, fungal DNA needs to be extracted and purified to a state suitable for laboratory use. Our laboratory has developed a simple method of extraction and purification of fungal DNA appropriate for enzymatic manipulation and polymerase chain reaction (PCR) appli...

  2. Materials for next-generation desalination and water purification membranes

    NASA Astrophysics Data System (ADS)

    Werber, Jay R.; Osuji, Chinedum O.; Elimelech, Menachem

    2016-05-01

    Membrane-based separations for water purification and desalination have been increasingly applied to address the global challenges of water scarcity and the pollution of aquatic environments. However, progress in water purification membranes has been constrained by the inherent limitations of conventional membrane materials. Recent advances in methods for controlling the structure and chemical functionality in polymer films can potentially lead to new classes of membranes for water purification. In this Review, we first discuss the state of the art of existing membrane technologies for water purification and desalination, highlight their inherent limitations and establish the urgent requirements for next-generation membranes. We then describe molecular-level design approaches towards fabricating highly selective membranes, focusing on novel materials such as aquaporin, synthetic nanochannels, graphene and self-assembled block copolymers and small molecules. Finally, we highlight promising membrane surface modification approaches that minimize interfacial interactions and enhance fouling resistance.

  3. 6. Vacuum purification room and upper level offices Bureau ...

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

    6. Vacuum purification room and upper level offices - Bureau of Mines Boulder City Experimental Station, Titanium Research Building, Date Street north of U.S. Highway 93, Boulder City, Clark County, NV

  4. Rapid magnetic catch-and-release purification by hydrophobic interactions.

    PubMed

    Iijima, Motoyuki; Mikami, Yuzuru; Yoshioka, Tomohiko; Kim, Shokaku; Kamiya, Hidehiro; Chiba, Kazuhiro

    2009-09-15

    A reversible, conventional, and rapid purification method of hydrophobically tagged products using hydrophobic magnetic nanoparticles was developed. The reversible purification system entails simply controlling the polarity of solvents. First, for the catching procedure, poor solvents were added into a well-dispersed system of magnetic nanoparticles and tagged products. Once the poor solvents were added to the system, the products were recrystallized among the nanoparticles and the aggregation of magnetic nanoparticles occurred due to hydrophobic interactions. These aggregates with the products contained within them were able to be collected rapidly by magnets. Then, the releasing procedure can be easily performed by redispersing the collected aggregates into good solvents. The availability of this purification protocol was confirmed by using a hydrophobically tagged fluorescent model product. Furthermore, this rapid purification method was successfully applied to a peptide elongation reaction system which enabled the synthesis of peptides such as Leu-Enkephalin in high purity, in high yield, and in a short time.

  5. Renaissance of protein crystallization and precipitation in biopharmaceuticals purification.

    PubMed

    Dos Santos, Raquel; Carvalho, Ana Luísa; Roque, A Cecília A

    The current chromatographic approaches used in protein purification are not keeping pace with the increasing biopharmaceutical market demand. With the upstream improvements, the bottleneck shifted towards the downstream process. New approaches rely in Anything But Chromatography methodologies and revisiting former techniques with a bioprocess perspective. Protein crystallization and precipitation methods are already implemented in the downstream process of diverse therapeutic biological macromolecules, overcoming the current chromatographic bottlenecks. Promising work is being developed in order to implement crystallization and precipitation in the purification pipeline of high value therapeutic molecules. This review focuses in the role of these two methodologies in current industrial purification processes, and highlights their potential implementation in the purification pipeline of high value therapeutic molecules, overcoming chromatographic holdups.

  6. Purification of human platelet-derived growth factor

    SciTech Connect

    Raines, E.W.; Ross, R.

    1985-01-01

    The paper describes a method for purification of human platelet-derived growth factor (PDGF) from outdated platelet-rich plasma (PRP) using commonly available laboratory reagents and yielding a mitogen purified 800,000-fold over the starting material. (/sup 3/H)thymidine incorporation into DNA of cultured cells responsive to PDGF represents the most readily available method to follow its purification and define the biological activity of a purified preparation. Other assays to quantitate PDGF include radioreceptor assay and radioimmunoassay.

  7. New data on electron-beam purification of wastewater

    NASA Astrophysics Data System (ADS)

    Pikaev, A. K.

    2002-11-01

    Recent environmental applications of radiation technology, developed in the author's laboratory, are presented in this paper. They are electron-beam and coagulation purification of molasses distillery slops from distillery-produced ethyl alcohol by fermentation of plant materials, electron-beam purification of wastewater from carboxylic acids (for example, formic acid) and removal of petroleum products (diesel fuel, motor oil and residual fuel oil) from water by γ-irradiation.

  8. Economic Methods of Ginger Protease'sextraction and Purification

    NASA Astrophysics Data System (ADS)

    Qiao, Yuanyuan; Tong, Junfeng; Wei, Siqing; Du, Xinyong; Tang, Xiaozhen

    This article reports the ginger protease extraction and purification methods from fresh ginger rhizome. As to ginger protease extraction, we adapt the steps of organic solvent dissolving, ammonium sulfate depositing and freeze-drying, and this method can attain crude enzyme powder 0.6% weight of fresh ginger rhizome. The purification part in this study includes two steps: cellulose ion exchange (DEAE-52) and SP-Sephadex 50 chromatography, which can purify crude ginger protease through ion and molecular weight differences respectively.

  9. Production, purification, and capsid stability of rhinovirus C types.

    PubMed

    Griggs, Theodor F; Bochkov, Yury A; Nakagome, Kazuyuki; Palmenberg, Ann C; Gern, James E

    2015-06-01

    The rhinovirus C (RV-C) were discovered in 2006 and these agents are an important cause of respiratory morbidity. Little is known about their biology. RV-C15 (C15) can be produced by transfection of recombinant viral RNA into cells and subsequent purification over a 30% sucrose cushion, even though yields and infectivity of other RV-C genotypes with this protocol are low. The goal of this study was to determine whether poor RV-C yields were due to capsid instability, and moreover, to develop a robust protocol suitable for the purification of many RV-C types. Capsid stability assays indicated that virions of RV-C41 (refractory to purification) have similar tolerance for osmotic and temperature stress as RV-A16 (purified readily), although C41 is more sensitive to low pH. Modification to the purification protocol by removing detergent increased the yield of RV-C. Addition of nonfat dry milk to the sucrose cushion increased the virus yield but sacrificed purity of the viral suspension. Analysis of virus distribution following centrifugation indicated that the majority of detectable viral RNA (vRNA) was found in pellets refractory to resuspension. Reduction of the centrifugal force with commiserate increase in spin-time improved the recovery of RV-C for both C41 and C2. Transfection of primary lung fibroblasts (WisL cells) followed by the modified purification protocol further improved yields of infectious C41 and C2. Described herein is a higher yield purification protocol suitable for RV-C types refractory to the standard purification procedure. The findings suggest that aggregation-adhesion problems rather than capsid instability influence RV-C yield during purification.

  10. Purification and immobilization of Aspergillus niger. beta. -xylosidase

    SciTech Connect

    Oguntimein, G.B.; Reilly, P.J.

    1980-01-01

    ..beta..-Xylosidase from a commercial Aspergillus niger preparation was purified by differential ammonium sulfate precipitation and either gel permeation or cation exchange chromatography, giving 16-fold purification in 32% yield for the first technique or 27-fold purification in 19% yield for the second. Enzyme prepared by this method was immobilized to 10 different carriers, but only when it was bound to alumina with TiCl/sub 4/ and to alkylamine porous silica with glutaraldehyde were substantial efficiencies and stabilities achieved.

  11. Catalyst traces after chemical purification in CVD grown carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Biró, L. P.; Khanh, N. Q.; Horváth, Z. E.; Vértesy, Z.; Kocsonya, A.; Kónya, Z.; Osváth, Z.; Koós, A.; Gyulai, J.; Zhang, X. B.; Van Tendeloo, G.; Fonseca, A.; Nagy, J. B.

    2001-11-01

    For many applications, in particular for those in which transport occurs through carbon nanotubes (CNT), and for certain characterization techniques too, it is important to know whether traces of the catalyst used to grow the nanotubes are incorporated in the grown tubes. Nuclear analytical techniques (RBS, PIXE) and XRF were applied to investigate the transition metal content of CNTs after different steps of chemical purification. TEM and HRTEM were used to monitor the influence of purification process on the structure of the CNTs.

  12. Air quality inside subway metro indoor environment worldwide: A review.

    PubMed

    Xu, Bin; Hao, Jinliang

    2017-10-01

    The air quality in the subway metro indoor microenvironment has been of particular public concern. With specific reference to the growing demand of green transportation and sustainable development, subway metro systems have been rapidly developed worldwide in last decades. The number of metro commuters has continuously increased over recent years in metropolitan cities. In some cities, metro system has become the primary public transportation mode. Although commuters typically spend only 30-40min in metros, the air pollutants emitted from various interior components of metro system as well as air pollutants carried by ventilation supply air are significant sources of harmful air pollutants that could lead to unhealthy human exposure. Commuters' exposure to various air pollutants in metro carriages may cause perceivable health risk as reported by many environmental health studies. This review summarizes significant findings in the literature on air quality inside metro indoor environment, including pollutant concentration levels, chemical species, related sources and health risk assessment. More than 160 relevant studies performed across over 20 countries were carefully reviewed. These comprised more than 2000 individual measurement trips. Particulate matters, aromatic hydrocarbons, carbonyls and airborne bacteria have been identified as the primary air pollutants inside metro system. On this basis, future work could focus on investigating the chronic health risks of exposure to various air pollutants other than PM, and/or further developing advanced air purification unit to improve metro in-station air quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Purification of proteins by the use of hydrophobic zeolite Y.

    PubMed

    Klint, D; Arvidsson, P; Blum, Z; Eriksson, H

    1994-12-01

    Hydrophobic zeolite Y can be used as a fast and efficient and inexpensive matrix in the purification of proteins from crude extracts. Preferably the zeolite can be used in the first purification step, replacing the commonly used precipitation techniques with (NH4)2SO4 or ethanol. The time required for the zeolite prefractionation was a few hours compared to the much more time consuming precipitation procedure which demands centrifugation and subsequent dialysis. Proteins can be absorbed on the zeolite either in order to remove undesired proteins or to be subsequently eluted from the zeolite in order to achieve purification and concentration. Removal of undesired proteins is exemplified by the purification of horseradish peroxidase from a crude extract. The zeolite procedure enhanced the specific activity five times and provided a yield similar to that which was obtained by the use of standard procedures, (NH4)2SO4 fractionation and ion-exchange chromatography. Binding and subsequent elution of proteins from the zeolite is exemplified by the purification of monoclonal antibodies from hybridoma culture supernatants. Proteins were desorbed from the zeolite by the use of polyethylene glycol 600 and this procedure yielded a purification factor of 5.

  14. Monogamy, polygamy, and other properties of entanglement of purification

    NASA Astrophysics Data System (ADS)

    Bagchi, Shrobona; Pati, Arun Kumar

    2015-04-01

    For bipartite pure and mixed quantum states, in addition to the quantum mutual information, there is another measure of total correlation, namely, the entanglement of purification. We study the monogamy, polygamy, and additivity properties of the entanglement of purification for pure and mixed states. In this paper, we show that, in contrast to the quantum mutual information which is strictly monogamous for any tripartite pure states, the entanglement of purification is polygamous for the same. This shows that there can be genuinely two types of total correlation across any bipartite cross in a pure tripartite state. Furthermore, we find the lower bound and actual values of the entanglement of purification for different classes of tripartite and higher-dimensional bipartite mixed states. Thereafter, we show that if entanglement of purification is not additive on tensor product states, it is actually subadditive. Using these results, we identify some states which are additive on tensor products for entanglement of purification. The implications of these findings on the quantum advantage of dense coding are briefly discussed, whereby we show that for tripartite pure states, it is strictly monogamous and if it is nonadditive, then it is superadditive on tensor product states.

  15. Purification of cerium, neodymium and gadolinium for low background experiments

    NASA Astrophysics Data System (ADS)

    Boiko, R. S.; Barabash, A. S.; Belli, P.; Bernabei, R.; Cappella, F.; Cerulli, R.; Danevich, F. A.; Incicchitti, A.; Laubenstein, M.; Mokina, V. M.; Nisi, S.; Poda, D. V.; Polischuk, O. G.; Tretyak, V. I.

    2014-01-01

    Cerium, neodymium and gadolinium contain double beta active isotopes. The most interesting are 150Nd and 160Gd (promising for 0ν2β search), 136Ce (2β+ candidate with one of the highest Q2β). The main problem of compounds containing lanthanide elements is their high radioactive contamination by uranium, radium, actinium and thorium. The new generation 2β experiments require development of methods for a deep purification of lanthanides from the radioactive elements. A combination of physical and chemical methods was applied to purify cerium, neodymium and gadolinium. Liquid-liquid extraction technique was used to remove traces of Th and U from neodymium, gadolinium and for purification of cerium from Th, U, Ra and K. Co-precipitation and recrystallization methods were utilized for further reduction of the impurities. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe gamma spectrometry. As a result of the purification procedure the radioactive contamination of gadolinium oxide (a similar purification efficiency was reached also with cerium and neodymium oxides) was decreased from 0.12 Bq/kg to 0.007 Bq/kg in 228Th, from 0.04 Bq/kg to <0.006 Bq/kg in 226Ra, and from 0.9 Bq/kg to 0.04 Bq/kg in 40K. The purification methods are much less efficient for chemically very similar radioactive elements like actinium, lanthanum and lutetium.

  16. (67)Ga and (68)Ga purification studies: preliminary results.

    PubMed

    Costa, R F; Barboza, M F; Osso, J A

    2013-01-01

    The positron emission tomography technique is very useful for diagnosis of several diseases. (68)Ga is a positron emitter with half-life of 67.7 min. As it is available from (68)Ge/(68)Ga generator systems, it is not necessary to have a nearby cyclotron. However, the eluate from commercial generators contains high levels of metallic impurities, which compete with (68)Ga in biomolecular labeling. Thus, a subsequent purification step is needed after generator elution. Here we present the results of two different methods developed for handmade purification of (68)Ga and (67)Ga for subsequent radiolabeling of biomolecules. Two purification methods were employed. The first one uses a cation exchange resin, and (68)Ga is eluted with a solution of acetone/acid. The second method of purification is performed by column chromatography solvent extraction, with (68)Ga recovery in deionized water. The best result was achieved with cationic resin AG50W-X8 (>400 mesh). However, the resin is not commercially available. The extraction chromatography column based on absorption of diisopropyl ether in XAD-16 is the most promising purification method. Although the levels of (68)Ga recovery and purification were smaller with the cationic resin method, its advantage is the (68)Ga recovery in deionized water.

  17. A new look at xylanases: an overview of purification strategies.

    PubMed

    Sá-Pereira, Paula; Paveia, Helena; Costa-Ferreira, Maria; Aires-Barros, Maria

    2003-07-01

    Interest in xylanases from different sources has increased markedly in the past decade, in part because of the application of these enzymes in the pulp and paper industry. Purity and purification costs are becoming important issues in modern biotechnology as the industry matures and competitive products reach the marketplace. Thus, new paths for successful and efficient xylanase recovery have to be followed. This article reviews the isolation and purification methods used for the recovery of microbial xylanases. Origins and applications of xylanases are described, highlighting the special features of this class of enzymes, such as the carbohydrate-binding domains (CBDs) and their importance in the development of affinity methodologies to increase and facilitate xylanase purification. Implications of recombinant DNA technology for the isolation and purification of xylanases are evaluated. Several purification procedures are analyzed, taking into consideration the sequence of the methods used in each and the number of times each method is used. New directions to improve xylanase separation and purification from fermentation media are described.

  18. Air Apparent.

    ERIC Educational Resources Information Center

    Harbster, David A.

    1988-01-01

    Explains the principle upon which a barometer operates. Describes how to construct two barometric devices for use in the classroom that show air's changing pressure. Cites some conditions for predicting weather. (RT)

  19. Air Pollution

    MedlinePlus

    ... tobacco smoke. How is air pollution linked to climate change? While climate change is a global process, it ... ozone levels are also a concern. Impacts of Climate Change on Human Health in the United States: A ...

  20. Air Apparent.

    ERIC Educational Resources Information Center

    Harbster, David A.

    1988-01-01

    Explains the principle upon which a barometer operates. Describes how to construct two barometric devices for use in the classroom that show air's changing pressure. Cites some conditions for predicting weather. (RT)

  1. Dosimetric assessment from 212Pb inhalation at a thorium purification plant.

    PubMed

    Campos, M P; Pecequilo, B R S

    2004-01-01

    At the Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, Brazil, there is a facility (thorium purification plant) where materials with high thorium concentrations are manipulated. In order to estimate afterwards the lung cancer risk for the workers, the thoron daughter (212Pb) levels were assessed and the committed effective and lung committed equivalent doses for workers in place. A total of 28 air filter samples were measured by total alpha counting through the modified Kusnetz method, to determine the 212Pb concentraion. The committed effective dose and lung committed equivalent dose due to 212Pb inhalation were derived from compartmental analysis following the ICRP 66 lung compartmental model, and ICRP 67 lead metabolic model.

  2. Strategies for automated sample preparation, nucleic acid purification, and concentration of low-target-number nucleic acids in environmental and food processing samples

    NASA Astrophysics Data System (ADS)

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

    1999-01-01

    The purpose of this work is to develop a rapid, automated system for nucleic acid purification and concentration from environmental and food processing samples. Our current approach involves off-line filtration and cell lysis (ballistic disintegration) functions in appropriate buffers followed by automated nucleic acid capture and purification on renewable affinity matrix microcolumns. Physical cell lysis and renewable affinity microcolumns eliminate the need for toxic organic solvents, enzyme digestions or other time- consuming sample manipulations. Within the renewable affinity microcolumn, we have examined nucleic acid capture and purification efficiency with various microbead matrices (glass, polymer, paramagnetic), surface derivitization (sequence-specific capture oligonucleotides or peptide nucleic acids), and DNA target size and concentration under variable solution conditions and temperatures. Results will be presented comparing automated system performance relative to benchtop procedures for both clean (pure DNA from a laboratory culture) and environmental (soil extract) samples, including results which demonstrate 8 minute purification and elution of low-copy nucleic acid targets from a crude soil extract in a form suitable for PCR or microarray-based detectors. Future research will involve the development of improved affinity reagents and complete system integration, including upstream cell concentration and cell lysis functions and downstream, gene-based detectors. Results of this research will ultimately lead to improved processes and instrumentation for on-line, automated monitors for pathogenic micro-organisms in food, water, air, and soil samples.

  3. Case studies on the physical-chemical parameters' variation during three different purification approaches destined to treat wastewaters from food industry.

    PubMed

    Ghimpusan, Marieta; Nechifor, Gheorghe; Nechifor, Aurelia-Cristina; Dima, Stefan-Ovidiu; Passeri, Piero

    2016-07-26

    The paper presents a set of three interconnected case studies on the depuration of food processing wastewaters by using aeration & ozonation and two types of hollow-fiber membrane bioreactor (MBR) approaches. A secondary and more extensive objective derived from the first one is to draw a clearer, broader frame on the variation of physical-chemical parameters during the purification of wastewaters from food industry through different operating modes with the aim of improving the management of water purification process. Chemical oxygen demand (COD), pH, mixed liquor suspended solids (MLSS), total nitrogen, specific nitrogen (NH4(+), NO2(-), NO3(-)) total phosphorous, and total surfactants were the measured parameters, and their influence was discussed in order to establish the best operating mode to achieve the purification performances. The integrated air-ozone aeration process applied in the second operating mode lead to a COD decrease by up to 90%, compared to only 75% obtained in a conventional biological activated sludge process. The combined purification process of MBR and ozonation produced an additional COD decrease of 10-15%, and made the Total Surfactants values to comply to the specific legislation.

  4. Hazardous Air Pollutants

    MedlinePlus

    ... Air Toxics Website Rules and Implementation Related Information Air Quality Data and Tools Clean Air Act Criteria Air ... Resources Visibility and Haze Voluntary Programs for Improving Air Quality Contact Us to ask a question, provide feedback, ...

  5. Air surveillance

    SciTech Connect

    Patton, G.W.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the air surveillance and monitoring programs currently in operation at that Hanford Site. Atmospheric releases of pollutants from Hanford to the surrounding region are a potential source of human exposure. For that reason, both radioactive and nonradioactive materials in air are monitored at a number of locations. The influence of Hanford emissions on local radionuclide concentrations was evaluated by comparing concentrations measured at distant locations within the region to concentrations measured at the Site perimeter. This section discusses sample collection, analytical methods, and the results of the Hanford air surveillance program. A complete listing of all analytical results summarized in this section is reported separately by Bisping (1995).

  6. Separation and Purification of Bacteria from Soil

    PubMed Central

    Bakken, Lars R.

    1985-01-01

    Bacteria were released and separated from soil by a simple blending-centrifugation procedure. The percent yield of bacterial cells (microscopic counts) in the supernatants varied over a wide range depending on the soil type. The superantants contained large amounts of noncellular organic material and clay particles. Further purification of the bacterial cells was obtained by centrifugation in density gradients, whereby the clay particles and part of the organic materials sedimented. A large proportion of the bacteria also sedimented through the density gradient, showing that they had a buoyant density above 1.2 g/ml. Attachment to clay minerals and humic material may account for this apparently high buoyant density. The percent yield of cells was negatively correlated with the clay content of the soils, whereas the purity was positively correlated with it. The cell size distribution and the relative frequency of colony-forming cells were similar in the soil homogenate, the supernatants after blending-centrifugation, and the purified bacterial fraction. In purified bacterial fraction from a clay loam, the microscopically measured biomass could account for 20 to 25% of the total C and 30 to 40% of the total N as cellular C and N. The amount of cellular C and N may be higher, however, owing to an underestimation of the cell diameter during fluorescence. A part of the contamination could be ascribed to extracellular structures as well as partly decayed cells, which were not revealed by fluorescence microscopy. PMID:16346816

  7. Biologically Inspired Purification and Dispersion of SWCNTs

    NASA Technical Reports Server (NTRS)

    Feeback, Daniel L.; Clarke, Mark S.; Nikolaev, Pavel

    2009-01-01

    A biologically inspired method has been developed for (1) separating single-wall carbon nanotubes (SWCNTs) from other materials (principally, amorphous carbon and metal catalysts) in raw production batches and (2) dispersing the SWCNTs as individual particles (in contradistinction to ropes and bundles) in suspension, as required for a number of applications. Prior methods of purification and dispersal of SWCNTs involve, variously, harsh physical processes (e.g., sonication) or harsh chemical processes (e.g., acid reflux). These processes do not completely remove the undesired materials and do not disperse bundles and ropes into individual suspended SWCNTs. Moreover, these processes cut long SWCNTs into shorter pieces, yielding typical nanotube lengths between 150 and 250 nm. In contrast, the present method does not involve harsh physical or chemical processes. The method involves the use of biologically derived dispersal agents (BDDAs) in an aqueous solution that is mechanically homogenized (but not sonicated) and centrifuged. The dense solid material remaining after centrifugation is resuspended by vortexing in distilled water, yielding an aqueous suspension of individual, separated SWCNTs having lengths from about 10 to about 15 microns.

  8. Purification of rabbit and human serum paraoxonase.

    PubMed

    Furlong, C E; Richter, R J; Chapline, C; Crabb, J W

    1991-10-22

    Rabbit serum paraoxonase/arylesterase has been purified to homogeneity by Cibacron Blue-agarose chromatography, gel filtration, DEAE-Trisacryl M chromatography, and preparative SDS gel electrophoresis. Renaturation (Copeland et al., 1982) and activity staining of the enzyme resolved by SDS gel electrophoresis allowed for identification and purification of paraoxonase. Two bands of active enzyme were purified by this procedure (35,000 and 38,000). Enzyme electroeluted from the preparative gels was reanalyzed by analytical SDS gel electrophoresis, and two higher molecular weight bands (43,000 and 48,000) were observed in addition to the original bands. This suggested that repeat electrophoresis resulted in an unfolding or other modification and slower migration of some of the purified protein. The lower mobility bands stained weakly for paraoxonase activity in preparative gels. Bands of each molecular weight species were electroblotted onto PVDF membranes and sequenced. The gas-phase sequence analysis showed that both the active bands and apparent molecular weight bands had identical amino-terminal sequences. Amino acid analysis of the four electrophoretic components from PVDF membranes also indicated compositional similarity. The amino-terminal sequences are typical of the leader sequences of secreted proteins. Human serum paraoxonase was purified by a similar procedure, and ten residues of the amino terminus were sequenced by gas-phase procedures. One amino acid difference between the first ten residues of human and rabbit was observed.

  9. RNA synthesis and purification for structural studies.

    PubMed

    Ahmed, Yasar Luqman; Ficner, Ralf

    2014-01-01

    RNAs play pivotal roles in the cell, ranging from catalysis (e.g., RNase P), acting as adaptor molecule (tRNA) to regulation (e.g., riboswitches). Precise understanding of its three-dimensional structures has given unprecedented insight into the molecular basis for all of these processes. Nevertheless, structural studies on RNA are still limited by the very special nature of this polymer. The most common methods for the determination of 3D RNA structures are NMR and X-ray crystallography. Both methods have their own set of requirements and give different amounts of information about the target RNA. For structural studies, the major bottleneck is usually obtaining large amounts of highly pure and homogeneously folded RNA. Especially for X-ray crystallography it can be necessary to screen a large number of variants to obtain well-ordered single crystals. In this mini-review we give an overview about strategies for the design, in vitro production, and purification of RNA for structural studies.

  10. Ultrafine polysaccharide nanofibrous membranes for water purification.

    PubMed

    Ma, Hongyang; Burger, Christian; Hsiao, Benjamin S; Chu, Benjamin

    2011-04-11

    Ultrafine polysaccharide nanofibers (i.e., cellulose and chitin) with 5-10 nm diameters were employed as barrier layers in a new class of thin-film nanofibrous composite (TFNC) membranes for water purification. In addition to concentration, the viscosity of the polysaccharide nanofiber coating suspension was also found to be affected by the pH value and ionic strength. When compared with two commercial UF membranes (PAN10 and PAN400), 10-fold higher permeation flux with above 99.5% rejection ratio were achieved by using ultrafine cellulose nanofibers-based TFNC membranes for ultrafiltration of oil/water emulsions. The very high surface-to-volume ratio and negatively charged surface of cellulose nanofibers, which lead to a high virus adsorption capacity as verified by MS2 bacteriophage testing, offer further opportunities in drinking water applications. The low cost of raw cellulose/chitin materials, the environmentally friendly fabrication process, and the impressive high-flux performance indicate that such ultrafine polysaccharide nanofibers-based TFNC membranes can surpass conventional membrane systems in many different water applications.

  11. Characterization and purification of bacteriophages using chromatofocusing.

    PubMed

    Brorson, Kurt; Shen, Hong; Lute, Scott; Pérez, Jessica Soto; Frey, Douglas D

    2008-10-17

    The technique of chromatofocusing was applied to the characterization and purification of three bacteriophages that are routinely used for testing virus filters: phiX174, PR772, and PP7. Chemically well-defined eluent buffers were used, instead of the more commonly used chromatofocusing polyampholyte buffers. Chromatographic column packings were selected to minimize band broadening by confining bacteriophage adsorption solely to the exterior particle surface. Under the conditions used it was determined that bacteriophages could be made to focus into narrow bands in a retained pH gradient with recoveries of live phage that ranged from 15 to nearly 100% as determined by a plaque-forming assay. Retention times and apparent isoelectric point data were obtained for samples consisting either of purified bacteriophage, or samples consisting of crude preparations of bacteriophages containing host cell impurities. Isoelectric point estimates were obtained using modified, previously described models. The results obtained suggest that chromatofocusing is a simple and rapid method for obtaining approximate isoelectric points for bacteriophages and probably other types of viruses. It is also likely a useful method for purifying these materials.

  12. Mouse Polyomavirus: Propagation, Purification, Quantification, and Storage.

    PubMed

    Horníková, Lenka; Žíla, Vojtěch; Španielová, Hana; Forstová, Jitka

    2015-08-03

    Mouse polyomavirus (MPyV) is a member of the Polyomaviridae family, which comprises non-enveloped tumorigenic viruses infecting various vertebrates including humans and causing different pathogenic responses in the infected organisms. Despite the variations in host tropism and pathogenicity, the structure of the virions of these viruses is similar. The capsid, with icosahedral symmetry (ø, 45 nm, T = 7d), is composed of a shell of 72 capsomeres of structural proteins, arranged around the nucleocore containing approximately 5-kbp-long circular dsDNA in complex with cellular histones. MPyV has been one of the most studied polyomaviruses and serves as a model virus for studies of the mechanisms of cell transformation and virus trafficking, and for use in nanotechnology. It can be propagated in primary mouse cells (e.g., in whole mouse embryo cells) or in mouse epithelial or fibroblast cell lines. In this unit, propagation, purification, quantification, and storage of MPyV virions are presented.

  13. Membrane Purification Cell for Aluminum Recycling

    SciTech Connect

    David DeYoung; James Wiswall; Cong Wang

    2011-11-29

    Recycling mixed aluminum scrap usually requires adding primary aluminum to the scrap stream as a diluent to reduce the concentration of non-aluminum constituents used in aluminum alloys. Since primary aluminum production requires approximately 10 times more energy than melting scrap, the bulk of the energy and carbon dioxide emissions for recycling are associated with using primary aluminum as a diluent. Eliminating the need for using primary aluminum as a diluent would dramatically reduce energy requirements, decrease carbon dioxide emissions, and increase scrap utilization in recycling. Electrorefining can be used to extract pure aluminum from mixed scrap. Some example applications include producing primary grade aluminum from specific scrap streams such as consumer packaging and mixed alloy saw chips, and recycling multi-alloy products such as brazing sheet. Electrorefining can also be used to extract valuable alloying elements such as Li from Al-Li mixed scrap. This project was aimed at developing an electrorefining process for purifying aluminum to reduce energy consumption and emissions by 75% compared to conventional technology. An electrolytic molten aluminum purification process, utilizing a horizontal membrane cell anode, was designed, constructed, operated and validated. The electrorefining technology could also be used to produce ultra-high purity aluminum for advanced materials applications. The technical objectives for this project were to: - Validate the membrane cell concept with a lab-scale electrorefining cell; - Determine if previously identified voltage increase issue for chloride electrolytes holds for a fluoride-based electrolyte system; - Assess the probability that voltage change issues can be solved; and - Conduct a market and economic analysis to assess commercial feasibility. The process was tested using three different binary alloy compositions (Al-2.0 wt.% Cu, Al-4.7 wt.% Si, Al-0.6 wt.% Fe) and a brazing sheet scrap composition (Al-2

  14. Purification and properties of rabconnectin-3.

    PubMed

    Sakisaka, Toshiaki; Takai, Yoshimi

    2005-01-01

    Rab3A, a member of the Rab3 small GTP-binding protein (G protein) family, regulates Ca(2+)-dependent exocytosis of neurotransmitter. The cyclical activation and inactivation of Rab3A are essential for the Rab3A action in exocytosis. GDP-Rab3A is activated to GTP-Rab3A by Rab3 GDP/GTP exchange protein (Rab3 GEP), and GTP-Rab3A is inactivated to GDP-Rab3A by Rab3 GTPase-activating protein (Rab3 GAP). We) have found a novel protein, named rabconnectin-3, that is coimmunoprecipitated with Rab3 GEP or GAP from the crude synaptic vesicle fraction of rat brain. Rabconnectin-3 constitutes a subunit structure consisting of alpha and beta subunits and localizes at synaptic vesicles. Overexpression of the C-terminal fragment of rabconnectin-3alpha inhibits Ca(2+)-dependent exocytosis from PC12 cells. We describe the purification method for native rabconnectin-3alpha and -3beta from rat brain and the functional properties of rabconnectin-3alpha in Ca(2+)-dependent exocytosis by use of human growth hormone coexpression assay system of PC12 cells.

  15. Isolation and Purification of Biotechnological Products

    NASA Astrophysics Data System (ADS)

    Hubbuch, Jürgen; Kula, Maria-Regina

    2007-05-01

    The production of modern pharma proteins is one of the most rapid growing fields in biotechnology. The overall development and production is a complex task ranging from strain development and cultivation to the purification and formulation of the drug. Downstream processing, however, still accounts for the major part of production costs. This is mainly due to the high demands on purity and thus safety of the final product and results in processes with a sequence of typically more than 10 unit operations. Consequently, even if each process step would operate at near optimal yield, a very significant amount of product would be lost. The majority of unit operations applied in downstream processing have a long history in the field of chemical and process engineering; nevertheless, mathematical descriptions of the respective processes and the economical large-scale production of modern pharmaceutical products are hampered by the complexity of the biological feedstock, especially the high molecular weight and limited stability of proteins. In order to develop new operational steps as well as a successful overall process, it is thus a necessary prerequisite to develop a deeper understanding of the thermodynamics and physics behind the applied processes as well as the implications for the product.

  16. Production, purification and properties of microbial phytases.

    PubMed

    Pandey, A; Szakacs, G; Soccol, C R; Rodriguez-Leon, J A; Soccol, V T

    2001-05-01

    Phytases (myo-inositol hexakisphosphate phosphohydrolase, EC 3.1.3.8) catalyse the release of phosphate from phytate (mycoinositol hexakiphosphate). Several cereal grains, legumes and oilseeds, etc., store phosphorus as phytate. Environmental pollution due to the high-phosphate manure, resulting in the accumulation of P at various locations has raised serious concerns. Phytases appear of significant value in effectively controlling P pollution. They can be produced from a host of sources including plants, animals and micro-organisms. Microbial sources, however, are promising for their commercial exploitations. Strains of Aspergillus sp., chiefly A. ficuum and A. niger have most commonly been employed for industrial purposes. Phytases are considered as a monomeric protein, generally possessing a molecular weight between 40 and 100 kDa. They show broad substrate specificity and have generally pH and temperature optima around 4.5-6.0 and 45-60 degrees C. The crystal structure of phytase has been determined at 2.5 A resolution. Immobilization of phytase has been found to enhance its thermostability. This article reviews recent trends on the production, purification and properties of microbial phytases.

  17. Neurotrophic factor - Characterization and partial purification

    NASA Technical Reports Server (NTRS)

    Popiela, H.; Ellis, S.

    1981-01-01

    Recent evidence suggests that neurotrophic activity is required for the normal proliferation and development of muscle cells. The present paper reports a study of the purification and characterization of a neurotrophic factor (NTF) from adult chicken ischiatic-peroneal nerves using two independent quantitative in vitro assay systems. The assays were performed by the measurement of the incorporation of tritiated thymidine or the sizes of single-cell clones by chick muscle cells grown in culture. The greatest amount of neutrotrophic activity is found to be extracted at a pH of 8; aqueous suspensions of the activity are stable to long-term storage at room temperature. The specific activity of the substance is doubled upon precipitation with ammonium sulfate or after gel filtration, and increase 4 to 5 fold after salt gradient elution from DEAE cellulose columns. The active fraction obtained after gel filtration and rechromatography on DEAE cellulose exhibits a 7 to 10-fold increase in specific activity. Electrophoresis of the most highly purified material yields a greatly concentrated band at around 80,000 daltons. Although NTF is purified almost 10-fold as indicated by the increase in specific activity, the maximum activity of the partially purified material is greatly reduced, possibly due to a requirement for a cofactor for the expression of maximum activity.

  18. Myxoma virus: propagation, purification, quantification, and storage.

    PubMed

    Smallwood, Sherin E; Rahman, Masmudur M; Smith, Dorothy W; McFadden, Grant

    2010-05-01

    Myxoma virus (MYXV) is a member of the Poxviridae family and prototype for the genus Leporipoxvirus. It is pathogenic only for European rabbits, in which it causes the lethal disease myxomatosis, and two North American species, in which it causes a less severe disease. MYXV replicates exclusively in the cytoplasm of the host cell. Although not infectious in humans, its genome encodes proteins that can interfere with or modulate host defense mechanisms; it is able to productively infect a number of human cancer cell lines, but not normal human cells, and has also been shown to increase survival time in mouse models of human glioma. These characteristics suggest that MYXV could be a viable therapeutic agent, e.g., in anti-inflammatory or anti-immune therapy, or as an oncolytic agent. MYXV is also an excellent model for poxvirus biology, pathogenesis, and host tropism studies. It is easily propagated in a number of cell lines, including adherent cells and suspension cultures, and minimal purification is required to provide a stock for in vivo and in vitro studies.

  19. Purification of tomato yellow leaf curl geminivirus.

    PubMed

    Luisoni, E; Milne, R G; Vecchiati, M

    1995-07-01

    Attempts were made to find a good purification procedure for tomato yellow leaf curl virus (TYLCV), a dangerous and continuously spreading whitefly-transmitted germinivirus, up to now only partially purified. Electron microscopy, serology and spectrophotometry were used to evaluate different procedures. The scheme finally adopted was the following: collect leaves and stems from Nicotiana benthamiana graft-infected 45-60 days previously (5-10 g/plant); homogenize with 0.5 M phosphate buffer pH 6 containing 2.5 mM NaEDTA, 10 mM Na2SO3, 0.1% 2-mercaptoethanol, 1% Triton X-100 and 0.1% Driselase (3-4 ml of buffer for each g of material); incubate overnight on ice with gentle agitation; filter; emulsify with 15% cold chloroform; centrifuge at low speed; ultracentrifuge supernatant; resuspend pellets in 0.5 M phosphate buffer pH 7 containing 2.5 mM NaEDTA; centrifuge at low speed; repeat resuspension of the pellets and low-speed centrifugation; ultracentrifuge the pooled supernatant on a Cs2SO4 gradient (e.g. for 5 h at 41,000 rpm); collect the virus band and dialyse or ultracentrifuge the virus. The virus yield was 5-10 mg per kg of tissue.

  20. Dicistroviridae: A new viral purification technique.

    PubMed

    Susevich, María L; Metz, Germán E; Marti, Gerardo A; Echeverría, María G

    2017-09-06

    The family Dicistroviridae comprises three genera and about twenty species of RNA virus, most of them with health or agricultural importance. The Triatoma virus (TrV) is the only entomopathogenic virus identified in triatomine bugs up to the present. TrV replicates within the intestinal epithelial cells, causing high mortality rate and delayed development of the molt of these bugs. TrV has been proposed as a biological control agent for vectors of Chagas disease. Viral particles were purified from feces of 1, 5 and 10 insects from an experimental colony of Triatoma infestans infected with TrV. Viral concentration and infectivity were corroborated using polyacrylamide gels and RT-PCR, respectively. In this work we report a method of viral purification that allows to reduce necessary reagents and time, using a very small amount of fecal matter. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  1. Purification and properties of thioether methyltransferase

    SciTech Connect

    Mozier, N.M.

    1988-01-01

    A method to assay activity was developed which measures acceptance of methyl groups from (methyl-{sup 3}H)-S-adenosylmethionine by dimethyl selenide. The product, ({sup 3}H)trimethylselenonium ion, is separated by HPLC and quantitated by scintillation counting. Thioether methyltransferase from mouse liver and lung resides primarily in the cytosol. In terms of specific activity the enzyme is most active in the lung and liver. Purification from lung cytosol requires a three-step process of DEAE and gel filtration column chromatographies followed by chromatofocusing. SDS-Polyacrylamide gel electrophoresis shows a single homogeneous band with a molecular mass of 28,000 daltons. Vmax and Km values for dimethyl selenide as a substrate are 15. 7 pmol/min and 0.44 {mu}M, respectively. Our studies have also shown that this purified enzyme is capable of methylating a wide range of compounds. To further test the enzyme's role in detoxification, in vivo studies were performed by injecting mice with substrate and (methyl-{sup 3}H)methionine and analyzing tissue extracts and urine for (methyl-{sup 3}H)sulfonium.

  2. Neurotrophic factor - Characterization and partial purification

    NASA Technical Reports Server (NTRS)

    Popiela, H.; Ellis, S.

    1981-01-01

    Recent evidence suggests that neurotrophic activity is required for the normal proliferation and development of muscle cells. The present paper reports a study of the purification and characterization of a neurotrophic factor (NTF) from adult chicken ischiatic-peroneal nerves using two independent quantitative in vitro assay systems. The assays were performed by the measurement of the incorporation of tritiated thymidine or the sizes of single-cell clones by chick muscle cells grown in culture. The greatest amount of neutrotrophic activity is found to be extracted at a pH of 8; aqueous suspensions of the activity are stable to long-term storage at room temperature. The specific activity of the substance is doubled upon precipitation with ammonium sulfate or after gel filtration, and increase 4 to 5 fold after salt gradient elution from DEAE cellulose columns. The active fraction obtained after gel filtration and rechromatography on DEAE cellulose exhibits a 7 to 10-fold increase in specific activity. Electrophoresis of the most highly purified material yields a greatly concentrated band at around 80,000 daltons. Although NTF is purified almost 10-fold as indicated by the increase in specific activity, the maximum activity of the partially purified material is greatly reduced, possibly due to a requirement for a cofactor for the expression of maximum activity.

  3. PLUTONIUM PURIFICATION PROCESS EMPLOYING THORIUM PYROPHOSPHATE CARRIER

    DOEpatents

    King, E.L.

    1959-04-28

    The separation and purification of plutonium from the radioactive elements of lower atomic weight is described. The process of this invention comprises forming a 0.5 to 2 M aqueous acidffc solution containing plutonium fons in the tetravalent state and elements with which it is normally contaminated in neutron irradiated uranium, treating the solution with a double thorium compound and a soluble pyrophosphate compound (Na/sub 4/P/sub 2/O/sub 7/) whereby a carrier precipitate of thorium A method is presented of reducing neptunium and - trite is advantageous since it destroys any hydrazine f so that they can be removed from solutions in which they are contained is described. In the carrier precipitation process for the separation of plutonium from uranium and fission products including zirconium and columbium, the precipitated blsmuth phosphate carries some zirconium, columbium, and uranium impurities. According to the invention such impurities can be complexed and removed by dissolving the contaminated carrier precipitate in 10M nitric acid, followed by addition of fluosilicic acid to about 1M, diluting the solution to about 1M in nitric acid, and then adding phosphoric acid to re-precipitate bismuth phosphate carrying plutonium.

  4. TMI-2 purification demineralizer resin study

    SciTech Connect

    Thompson, J D; Osterhoudt, T R

    1984-05-01

    Study of the Makeup and Purification System demineralizers at TMI-2 has established that fuel quantities in the vessels are low, precluding criticality, that the high radioactive cesium concentration on the demineralizer resins can be chemically removed, and that the demineralizer resins can probably be removed from the vessels by sluicing through existing plant piping. Radiation measurements from outside the demineralizers establishing that there is between 1.5 and 5.1 (probably 3.3) lb of fuel in the A vessel and less than that amount in the B vessel. Dose rates up to 2780 R per hour were measured on contact with the A demineralizer. Remote visual observation of the A demineralizer showed a crystalline crust overlaying amber-colored resins. The cesium activity in solid resin samples ranged from 220 to 16,900 ..mu..Ci/g. Based on this information, researchers concluded that the resins cannot be removed through the normal pathway in their present condition. Studies do show that the resins will withstand chemical processing designed to rinse and elute cesium from the resins. The process developed should work on the TMI-2 resins.

  5. Proanthocyanidin A2 purification and levels found in American cranberry (Vaccinium macrocarpon Ait.) products

    USDA-ARS?s Scientific Manuscript database

    In this study, five common proanthocyanidin purification techniques were evaluated prior to phloroglucinolysis, followed by HPLC analysis. An optimized purification method was then used to identify and quantify the proanthocyanidins (extension and terminal units of epigallocatechin, catechin, epicat...

  6. The Purification of a Blood Group A Glycoprotein: An Affinity Chromatography Experiment.

    ERIC Educational Resources Information Center

    Estelrich, J.; Pouplana, R.

    1988-01-01

    Describes a purification process through affinity chromatography necessary to obtain specific blood group glycoproteins from erythrocytic membranes. Discusses the preparation of erythrocytic membranes, extraction of glycoprotein from membranes, affinity chromatography purification, determination of glycoproteins, and results. (CW)

  7. Cell-Type-Specific mRNA Purification by Translating Ribosome Affinity Purification (TRAP)

    PubMed Central

    Heiman, Myriam; Kulicke, Ruth; Fenster, Robert J.; Greengard, Paul; Heintz, Nathaniel

    2014-01-01

    Cellular diversity and architectural complexity create barriers to understanding the function of the mammalian central nervous system (CNS) at a molecular level. To address this problem, we recently developed a methodology that provides the ability to profile the entire translated mRNA complement of any genetically defined cell population. This methodology, which we termed translating ribosome affinity purification, or TRAP, combines cell-type-specific transgene expression with affinity purification of translating ribosomes. TRAP can be used to study the cell-type-specific mRNA profiles of any genetically defined cell type, and has been successfully used to date in organisms ranging from D. melanogaster to mice and human cultured cells. Unlike other methodologies that rely upon micro-dissection, cell panning, or cell sorting, the TRAP methodology bypasses the need for tissue fixation or single-cell suspensions (and potential artifacts these treatments introduce), and reports on mRNAs in the entire cell body. This protocol provides a step-by-step guide to implementing the TRAP methodology, which takes two days to complete once all materials are in hand. PMID:24810037

  8. Purification of Golgi casein kinase from bovine milk.

    PubMed

    Duncan, J S; Wilkinson, M C; Burgoyne, R D

    2000-09-01

    Caseins and many other secretory proteins are phosphorylated during their transport through the secretory pathway by a protein kinase present within Golgi compartments. Molecular analysis of the Golgi casein kinase (GCK) has not been possible since it has not been purified to homogeneity or been cloned. Previous attempts have been made to purify GCK activity from mammary gland Golgi fractions, but these have not resulted in extensive purification of the enzyme. In the present study, we have demonstrated that substantial amounts of GCK activity, assayed using a specific peptide substrate, can be detected as a soluble form in bovine milk, and we have used milk as a source for purification. A purification protocol was established that allowed>80000-fold purification to a specific activity of GCK (approx. 700 nmoles/min per mg of protein) far higher than previously achieved. These findings cast doubts on previous claims for purification of GCK activity. In addition, ion-exchange chromatography resolved two closely eluting peaks of activity, suggesting the existence of two related, but distinct, GCK activities.

  9. High-throughput purification of single compounds and libraries.

    PubMed

    Schaffrath, Mathias; von Roedern, Erich; Hamley, Peter; Stilz, Hans Ulrich

    2005-01-01

    The need for increasing productivity in medicinal chemistry and associated improvements in automated synthesis technologies for compound library production during the past few years have resulted in a major challenge for compound purification technology and its organization. To meet this challenge, we have recently set up three full-service chromatography units with the aid of in-house engineers, different HPLC suppliers, and several companies specializing in custom laboratory automation technologies. Our goal was to combine high-throughput purification with the high attention to detail which would be afforded by a dedicated purification service. The resulting final purification laboratory can purify up to 1000 compounds/week in amounts ranging from 5 to 300 mg, whereas the two service intermediate purification units take 100 samples per week from 0.3 to 100 g. The technologies consist of normal-phase and reversed-phase chromatography, robotic fraction pooling and reformatting, a bottling system, an automated external solvent supply and removal system, and a customized, high-capacity freeze-dryer. All work processes are linked by an electronic sample registration and tracking system.

  10. Improved methods for magnetic purification of malaria parasites and haemozoin.

    PubMed

    Kim, Charles C; Wilson, Emily B; DeRisi, Joseph L

    2010-01-14

    Malaria parasites generate free haem upon catabolism of host haemoglobin during their intraerythrocytic growth cycle. In order to minimize oxidative toxicity of the ferric iron, the free haem molecules are polymerized into the biomineral beta-haematin (commonly referred to as haemozoin). Haemozoin crystals are paramagnetic, and this property can be exploited for the purification of late stage parasites as they contain larger haemozoin crystals than early stage parasites and uninfected cells. Commercially available magnets that were originally developed for the purpose of antibody-mediated cell purification are widely used for this purpose. As these methods are not necessarily optimized for parasite purification, the relationship between magnetic field strength and the quantity and quality of yield during parasite purification was explored. Inexpensive rare-earth neodymium magnets with commercially available disposable columns were employed to explore the relationship between magnetic field strength and recovery of free haemozoin and infected erythrocytes (iRBCs). Yields of free haemozoin increased nearly linearly with increasing magnetic field strength to the strongest fields tested (8,500 Gauss). Stronger magnetic fields also improved the recovery of iRBCs with no detrimental effects on parasite viability. An in-house constructed magnetic stand, built for $75 in materials, produced superior results when compared with much more expensive commercial products. Existing protocols for the magnetic purification of free haemozoin and iRBCs result in sub-optimal yields. Inexpensive high-strength neodymium magnets offer a better option, resulting in higher yields with no detrimental effects on parasite viability.

  11. Air Pollution.

    ERIC Educational Resources Information Center

    Scorer, Richard S.

    The purpose of this book is to describe the basic mechanisms whereby pollution is transported and diffused in the atmosphere. It is designed to give practitioners an understanding of basic mechanics and physics so they may have a correct basis on which to formulate their decisions related to practical air pollution control problems. Since many…

  12. Air Pollution.

    ERIC Educational Resources Information Center

    Scorer, Richard S.

    The purpose of this book is to describe the basic mechanisms whereby pollution is transported and diffused in the atmosphere. It is designed to give practitioners an understanding of basic mechanics and physics so they may have a correct basis on which to formulate their decisions related to practical air pollution control problems. Since many…

  13. /Air Atmospheres

    NASA Astrophysics Data System (ADS)

    Emami, Samar; Sohn, Hong Yong; Kim, Hang Goo

    2014-08-01

    Molten magnesium oxidizes rapidly when exposed to air causing melt loss and handling difficulties. The use of certain additive gases such as SF6, SO2, and CO2 to form a protective MgO layer over a magnesium melt has been proposed. The oxidation behavior of molten magnesium in air containing various concentrations of SF6 was investigated. Measurements of the kinetics of the oxide layer growth at various SF6 concentrations in air and temperatures were made. Experiments were performed using a thermogravimetric analysis unit in the temperature range of 943 K to 1043 K (670 °C to 770 °C). Results showed that a thin, coherent, and protective MgF2 layer was formed under SF6/Air mixtures, with a thickness ranging from 300 nm to 3 μm depending on SF6 concentration, temperature, and exposure time. Rate parameters were calculated and a model for the process was developed. The morphology and composition of the surface films were studied using scanning electron microscope and energy-dispersive spectroscope.

  14. 21 CFR 884.6170 - Assisted reproduction water and water purification systems.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Assisted reproduction water and water purification... Devices § 884.6170 Assisted reproduction water and water purification systems. (a) Identification. Assisted reproduction water purification systems are devices specifically intended to generate high...

  15. 21 CFR 884.6170 - Assisted reproduction water and water purification systems.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Assisted reproduction water and water purification... Devices § 884.6170 Assisted reproduction water and water purification systems. (a) Identification. Assisted reproduction water purification systems are devices specifically intended to generate high...

  16. Multiple-copy distillation and purification of phase-diffused squeezed states

    SciTech Connect

    Marek, Petr; Fiurasek, Jaromir; Hage, Boris; Franzen, Alexander; DiGugliemo, James; Schnabel, Roman

    2007-11-15

    We provide a detailed theoretical analysis of multiple-copy purification and distillation protocols for phase-diffused squeezed states of light. The standard iterative distillation protocol is generalized to a collective purification of an arbitrary number of N copies. We also derive a semianalytical expression for the asymptotic limit of the iterative distillation and purification protocol and discuss its properties.

  17. Design and research of adaptive control of purification process of biotrickling bed for VOC waste gas

    NASA Astrophysics Data System (ADS)

    Hu, Xin-Yu; Zhao, Ming-Fu; Luo, Kai; Luo, Bin-Bin; Ling, Wen-Hao

    2008-10-01

    Based on visualization test of biotrickling bed, we analyze the dynamicmodel of the purification process, and get the dynamic model on liquid flux and purification efficiency. The adaptive control strategy is applied in the purification process. The simulation test proves that under the same disturbance the adaptive control strategy is more effective than PID.

  18. 21 CFR 884.6170 - Assisted reproduction water and water purification systems.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Assisted reproduction water and water purification... Devices § 884.6170 Assisted reproduction water and water purification systems. (a) Identification. Assisted reproduction water purification systems are devices specifically intended to generate high...

  19. 21 CFR 884.6170 - Assisted reproduction water and water purification systems.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Assisted reproduction water and water purification... Devices § 884.6170 Assisted reproduction water and water purification systems. (a) Identification. Assisted reproduction water purification systems are devices specifically intended to generate high...

  20. 21 CFR 884.6170 - Assisted reproduction water and water purification systems.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Assisted reproduction water and water purification... Devices § 884.6170 Assisted reproduction water and water purification systems. (a) Identification. Assisted reproduction water purification systems are devices specifically intended to generate high...

  1. Nylon Wool Purification Alters the Activation of T Cells

    PubMed Central

    Wohler, Jillian E.; Barnum, Scott R.

    2009-01-01

    Purification of lymphocytes, particularly T cells, is commonly performed using nylon wool. This enrichment method selectively retains B cells and some myeloid cells allowing a significantly more pure T cell population to flow through a nylon wool column. T cells purified in this fashion are assumed to be unaltered and functionally naïve, however some studies have suggested aberrant in vitro T cell responses after nylon wool treatment. We found that nylon wool purification significantly altered T cell proliferation, expression of activation markers and production of cytokines. Our results suggest that nylon wool treatment modifies T cell activation responses and that caution should be used when choosing this purification method. PMID:18952296

  2. The Status of KamLAND After Purification

    NASA Astrophysics Data System (ADS)

    Grant, Christopher

    2010-02-01

    KamLAND is a 1-kton liquid scintillation detector located in the Kamioka underground laboratory, in Japan. KamLAND has provided a precision measurement of δm^221 using reactor anti-neutrinos, and yielded first observational evidence of geologically produced anti-neutrinos. Since April of 2007, the collaboration has been working on the purification of the detector with the goal of observing 862 keV, ^7Be solar neutrinos. Two purification campaigns have concluded, with a total of 5.4 ktons of scintillator circulated through a distillation and nitrogen purge system. The results of purification and the overall background reduction factors will be presented, along with an update of the ^7Be solar neutrino analysis. )

  3. Detection of protein-protein interactions using tandem affinity purification.

    PubMed

    Goodfellow, Ian; Bailey, Dalan

    2014-01-01

    Tandem affinity purification (TAP) is an invaluable technique for identifying interaction partners for an affinity tagged bait protein. The approach relies on the fusion of dual tags to the bait before separate rounds of affinity purification and precipitation. Frequently two specific elution steps are also performed to increase the specificity of the overall technique. In the method detailed here, the two tags used are protein G and a short streptavidin binding peptide; however, many variations can be employed. In our example the tags are separated by a cleavable tobacco etch virus protease target sequence, allowing for specific elution after the first round of affinity purification. Proteins isolated after the final elution step in this process are concentrated before being identified by mass spectrometry. The use of dual affinity tags and specific elution in this technique dramatically increases both the specificity and stringency of the pull-downs, ensuring a low level of background nonspecific interactions.

  4. Preparative Purification of Liriodendrin from Sargentodoxa cuneata by Macroporous Resin.

    PubMed

    Li, Di-Hua; Wang, Yan; Lv, Yuan-Shan; Liu, Jun-Hong; Yang, Lei; Zhang, Shu-Kun; Zhuo, Yu-Zhen

    2015-01-01

    The preparative purification of liriodendrin from Sargentodoxa cuneata using macroporous resin combined with crystallization process was evaluated. The properties of adsorption/desorption of liriodendrin on eight macroporous resins were investigated systematically. X-5 resin was selected as the most suitable medium for liriodendrin purification. The adsorption of liriodendrin on X-5 resin fitted well with the pseudo-second-order kinetic model and Langmuir isotherm model. Dynamic adsorption/desorption tests were performed using a glass column packed with X-5 resin to optimize the separation process of liriodendrin. After one treatment with X-5 resin, the content of liriodendrin in the product was increased 48.73-fold, from 0.85% to 41.42%, with a recovery yield of 88.9%. 97.48% liriodendrin was obtained by further crystallization and determined by HPLC. The purified product possessed strong antioxidant activity. In conclusion, purification of liriodendrin might expend its further pharmacological researches and further applications in pharmacy.

  5. Effect of additives on the purification of urease

    NASA Astrophysics Data System (ADS)

    Yu, X.; Wang, J.; Ulrich, J.

    2015-12-01

    The effect of additives on the purification of proteins was investigated. The target protein studied here is the enzyme urease. Studies on the purification of urease from jack bean meal were carried out. 32% (v/v) acetone was utilized to extract urease from the jack bean meal. Further purification by crystallization with the addition of 2-mercaptoethanol and EDTA disodium salt dehydrate was carried out. It was found out that the presence of additives can affect the selectivity of the crystallization. Increases in both purity and yield of the urease after crystallization were observed in the presence of additives, which were proven using both SDS-PAGE and activity. Urease crystals with a yield of 69.9% and a purity of 85.1% were obtained in one crystallization step in the presence of additives. Furthermore, the effect of additives on the thermodynamics and kinetics of urease crystallization was studied.

  6. A combined purification of fluorine-containing foul water

    SciTech Connect

    Sal'nikova, E.O.

    1986-05-01

    An experiment was carried out for two-stage water purification. A solution of AOC ( aluminum oxychloride) was added to a neutralized and clarified foul water and the pH brought up to 11.5 by lime water. After cleaning, the required components were identified. This method is simple and in relation to the apparatus used does not differ from the neutralization method. Therefore under industrial conditions the process can be carried out using the standard equipment. The hypothesis that flouride is codeposited with CHSA-3 has been confirmed experimentally. With additional purification using the sulfo-aluminate method, the value of the pH immediately after deposition is greater than the norm. The results obtained have made it possible to develop a simple, effective method of combining high purification of foul water from flourine and sulfates with the simultaneous additional deposition of heavy ferrous metals.

  7. LARGE SCALE PURIFICATION OF PROTEINASES FROM CLOSTRIDIUM HISTOLYTICUM FILTRATES

    PubMed Central

    Conklin, David A.; Webster, Marion E.; Altieri, Patricia L.; Berman, Sanford; Lowenthal, Joseph P.; Gochenour, Raymond B.

    1961-01-01

    Conklin, David A. (Walter Reed Army Institute of Research, Washington, D. C.), Marion E. Webster, Patricia L. Altieri, Sanford Berman, Joseph P. Lowenthal, and Raymond B. Gochenour. Large scale purification of proteinases from Clostridium histolyticum filtrates. J. Bacteriol. 82:589–594. 1961.—A method for the large scale preparation and partial purification of Clostridium histolyticum proteinases by fractional precipitation with ammonium sulfate is described. Conditions for adequate separation and purification of the δ-proteinase and the gelatinase were obtained. Collagenase, on the other hand, was found distributed in four to five fractions and little increase in purity was achieved as compared to the crude ammonium sulfate precipitates. PMID:13880849

  8. Purification of porcine proinsulin by high-performance liquid chromatography.

    PubMed

    Parman, A U; Rideout, J M

    1983-02-04

    A procedure has been developed for purification of porcine proinsulin by high-performance liquid chromatography from a preparation obtained as a side product during the Sephadex G-50 gel filtration of an impure porcine insulin preparation. Reversed-phase chromatography was carried out on octadecylsilica as the stationary phase with graded mixtures of acetonitrile or methanol-acetonitrile and phosphate buffer pH 2.4 as the mobile phase. The crude preparation separated into five different groups of proteins, the proinsulin-containing peak being identified by the co-eluting internal proinsulin marker. After purification by conventional procedures (separation, pooling, freeze drying, desalting, reprecipitation and drying) this peak fraction was rechromatographed by high-performance liquid chromatography (for final purification) to give a single peak protein which had identical electrophoretic mobility to that of commercial porcine proinsulin, and which converted to a protein with electrophoretic mobility similar to that of porcine insulin.

  9. Bromelain: an overview of industrial application and purification strategies.

    PubMed

    Arshad, Zatul Iffah Mohd; Amid, Azura; Yusof, Faridah; Jaswir, Irwandi; Ahmad, Kausar; Loke, Show Pau

    2014-09-01

    This review highlights the use of bromelain in various applications with up-to-date literature on the purification of bromelain from pineapple fruit and waste such as peel, core, crown, and leaves. Bromelain, a cysteine protease, has been exploited commercially in many applications in the food, beverage, tenderization, cosmetic, pharmaceutical, and textile industries. Researchers worldwide have been directing their interest to purification strategies by applying conventional and modern approaches, such as manipulating the pH, affinity, hydrophobicity, and temperature conditions in accord with the unique properties of bromelain. The amount of downstream processing will depend on its intended application in industries. The breakthrough of recombinant DNA technology has facilitated the large-scale production and purification of recombinant bromelain for novel applications in the future.

  10. STUDIES ON THE PURIFICATION OF BACTERIOPHAGE.

    PubMed

    Kalmanson, G; Bronfenbrenner, J

    1939-11-20

    A simple method of concentrating and purifying bacteriophage has been described. The procedure consisted essentially in collecting the active agent on a reinforced collodion membrane of a porosity that would just retain all the active agent and permit extraneous material to pass through. Advantage was taken of the fact that B. coli will proliferate and regenerate bacteriophage in a completely diffusible synthetic medium with ammonia as the only source of nitrogen, which permitted the purification of the bacteriophage by copious washing. The material thus obtained was concentrated by suction and after thorough washing possessed all the activity of the original filtrate. It was labile, losing its activity in a few days on standing, and was quickly and completely inactivated upon drying. This material contained approximately 15 per cent of nitrogen and with 2 or 3 mg. samples of inactive dry residue it was possible to obtain positive protein color tests. The concentrated and purified bacteriophage has about 10(-14) mg. of nitrogen, or 6 x 10(-17) gm. of protein per unit of lytic activity. Assuming that each unit of activity represents a molecule, the calculated maximum average molecular weight would be approximately 36,000,000, and on the assumption of a spherical shape of particles and a density of 1.3, the calculated radius would be about 22 millimicra. By measurement of the diffusion rate, the average radius of particle of the fraction of the purified bacteriophage which diffuses most readily through a porous plate was found to be of the order of magnitude of 9 millimicra, or of a calculated molecular weight of 2,250,000. Furthermore, when this purified bacteriophage was fractionated by forcing it through a thin collodion membrane, which permits the passage of only the smaller particles, it was possible to demonstrate in the ultrafiltrate active particles of about 2 millimicra in radius, and of a calculated molecular weight of 25,000. It was of interest to apply

  11. Copper(I)/TEMPO Catalyzed Aerobic Oxidation of Primary Alcohols to Aldehydes with Ambient Air

    PubMed Central

    Hoover, Jessica M.; Steves, Janelle E.; Stahl, Shannon S.

    2012-01-01

    This protocol describes a practical laboratory-scale method for aerobic oxidation of primary alcohols to aldehydes, using a chemoselective CuI/TEMPO catalyst system. The catalyst is prepared in situ from commercially available reagents, and the reactions are performed in a common organic solvent (acetonitrile) with ambient air as the oxidant. Three different reaction conditions and three procedures for the isolation and purification of the aldehyde product are presented. The oxidations of eight different alcohols, described here, include representative examples of each reaction condition and purification method. Reaction times vary from 20 min to 24 h, depending on the alcohol, while the purification methods each take about 2 h. The total time necessary for the complete protocol ranges from 3 – 26 h. PMID:22635108

  12. Chromatography purification of canine adenoviral vectors.

    PubMed

    Segura, María Mercedes; Puig, Meritxell; Monfar, Mercè; Chillón, Miguel

    2012-06-01

    Canine adenovirus vectors (CAV2) are currently being evaluated for gene therapy, oncolytic virotherapy, and as vectors for recombinant vaccines. Despite the need for increasing volumes of purified CAV2 preparations for preclinical and clinical testing, their purification still relies on the use of conventional, scale-limited CsCl ultracentrifugation techniques. A complete downstream processing strategy for CAV2 vectors based on membrane filtration and chromatography is reported here. Microfiltration and ultra/diafiltration are selected for clarification and concentration of crude viral stocks containing both intracellular and extracellular CAV2 particles. A DNase digestion step is introduced between ultrafiltration and diafiltration operations. At these early stages, concentration of vector stocks with good recovery of viral particles (above 80%) and removal of a substantial amount of protein and nucleic acid contaminants is achieved. The ability of various chromatography techniques to isolate CAV2 particles was evaluated. Hydrophobic interaction chromatography using a Fractogel propyl tentacle resin was selected as a first chromatography step, because it allows removal of the bulk of contaminating proteins with high CAV2 yields (88%). An anion-exchange chromatography step using monolithic supports is further introduced to remove the remaining contaminants with good recovery of CAV2 particles (58-69%). The main CAV2 viral structural components are visualized in purified preparations by electrophoresis analyses. Purified vector stocks contained intact icosahedral viral particles, low contamination with empty viral capsids (10%), and an acceptable total-to-infectious particle ratio (below 30). The downstream processing strategy that was developed allows preparation of large volumes of high-quality CAV2 stocks.

  13. Multispecies Purification of Testicular Germ Cells.

    PubMed

    Lima, Ana C; Jung, Min; Rusch, Jannette; Usmani, Abul; Lopes, Alexandra; Conrad, Donald F

    2016-08-24

    Advanced methods of cellular purification are required to apply genome technology to the study of spermatogenesis. One approach, based on flow cytometry of murine testicular cells stained with Hoechst-33342 (Ho-FACS), has been extensively optimized and currently allows the isolation of 9 germ cell types. This staining technique is straightforward to implement, highly effective at purifying specific germ cell types and yields sufficient cell numbers for high throughput studies. Ho-FACS is a technique that does not require species-specific markers, but whose applicability to other species is largely unexplored. We hypothesized that, due to the similar cell physiology of spermatogenesis across mammals, Ho-FACS could be used to produce highly purified subpopulations of germ cells in mammals other than mouse. To test this hypothesis, we applied Ho-FACS to 4 mammalian species that are widely used in testis research - Rattus norvegicus, Cavia porcellus, Canis familiaris and Sus scrofa domesticus We successfully isolated 4 germ cell populations from these species with average purity of 79% for spermatocytes, and 90% for spermatids and 66% for spermatogonia. Additionally, we compare the performance of mechanical and chemical dissociation for each species, and propose an optimized gating strategy to better discriminate round and elongating spermatids in the mouse, which can potentially be applied to other species. Our work indicates that spermatogenesis may be uniquely accessible among mammalian developmental systems, as a single set of reagents may be sufficient to isolate germ cell populations from many different mammalian species, opening new avenues in the fields of development and male reproductive biology.

  14. Multispecies Purification of Testicular Germ Cells1

    PubMed Central

    Lima, Ana C.; Jung, Min; Rusch, Jannette; Usmani, Abul; Lopes, Alexandra M.; Conrad, Donald F.

    2016-01-01

    Advanced methods of cellular purification are required to apply genome technology to the study of spermatogenesis. One approach, based on flow cytometry of murine testicular cells stained with Hoechst-33342 (Ho-FACS), has been extensively optimized and currently allows the isolation of nine germ cell types. This staining technique is straightforward to implement, is highly effective at purifying specific germ cell types, and yields sufficient cell numbers for high-throughput studies. Ho-FACS is a technique that does not require species-specific markers, but whose applicability to other species is largely unexplored. We hypothesized that, because of the similar cell physiology of spermatogenesis across mammals, Ho-FACS could be used to produce highly purified subpopulations of germ cells in mammals other than mouse. To test this hypothesis, we applied Ho-FACS to four mammalian species that are widely used in testis research: Rattus norvegicus, Cavia porcellus, Canis familiaris, and Sus scrofa domesticus. We successfully isolated four germ cell populations from these species with average purity of 79% for spermatocytes, 90% for spermatids, and 66% for spermatogonia. Additionally, we compare the performance of mechanical and chemical dissociation for each species, and propose an optimized gating strategy to better discriminate round and elongating spermatids in the mouse, which can potentially be applied to other species. Our work indicates that spermatogenesis may be uniquely accessible among mammalian developmental systems, as a single set of reagents may be sufficient to isolate germ cell populations from many different mammalian species, opening new avenues in the fields of development and male reproductive biology. PMID:27557646

  15. Carbohydrate-mediated purification of petrochemicals.

    PubMed

    Holcroft, James M; Hartlieb, Karel J; Moghadam, Peyman Z; Bell, Jon G; Barin, Gokhan; Ferris, Daniel P; Bloch, Eric D; Algaradah, Mohammed M; Nassar, Majed S; Botros, Youssry Y; Thomas, K Mark; Long, Jeffrey R; Snurr, Randall Q; Stoddart, J Fraser

    2015-05-06

    Metal-organic frameworks (MOFs) are known to facilitate energy-efficient separations of important industrial chemical feedstocks. Here, we report how a class of green MOFs-namely CD-MOFs-exhibits high shape selectivity toward aromatic hydrocarbons. CD-MOFs, which consist of an extended porous network of γ-cyclodextrins (γ-CDs) and alkali metal cations, can separate a wide range of benzenoid compounds as a result of their relative orientation and packing within the transverse channels formed from linking (γ-CD)6 body-centered cuboids in three dimensions. Adsorption isotherms and liquid-phase chromatographic measurements indicate a retention order of ortho- > meta- > para-xylene. The persistence of this regioselectivity is also observed during the liquid-phase chromatography of the ethyltoluene and cymene regioisomers. In addition, molecular shape-sorting within CD-MOFs facilitates the separation of the industrially relevant BTEX (benzene, toluene, ethylbenzene, and xylene isomers) mixture. The high resolution and large separation factors exhibited by CD-MOFs for benzene and these alkylaromatics provide an efficient, reliable, and green alternative to current isolation protocols. Furthermore, the isolation of the regioisomers of (i) ethyltoluene and (ii) cymene, together with the purification of (iii) cumene from its major impurities (benzene, n-propylbenzene, and diisopropylbenzene) highlight the specificity of the shape selectivity exhibited by CD-MOFs. Grand canonical Monte Carlo simulations and single component static vapor adsorption isotherms and kinetics reveal the origin of the shape selectivity and provide insight into the capability of CD-MOFs to serve as versatile separation platforms derived from renewable sources.

  16. Carbon Nanotube Membranes for Water Purification

    NASA Astrophysics Data System (ADS)

    Bakajin, Olgica

    2009-03-01

    Carbon nanotubes are an excellent platform for the fundamental studies of transport through channels commensurate with molecular size. Water transport through carbon nanotubes is also believed to be similar to transport in biological channels such as aquaporins. I will discuss the transport of gas, water and ions through microfabricated membranes with sub-2 nanometer aligned carbon nanotubes as ideal atomically-smooth pores. The measured gas flow through carbon nanotubes exceeded predictions of the Knudsen diffusion model by more than an order of magnitude. The measured water flow exceeded values calculated from continuum hydrodynamics models by more than three orders of magnitude and is comparable to flow rates extrapolated from molecular dynamics simulations and measured for aquaporins. More recent reverse osmosis experiments reveal ion rejection by our membranes. Based on our experimental findings, the current understanding of the fundamentals of water and gas transport and of ion rejection will be discussed. The potential application space that exploits these unique nanofluidic phenomena will be explored. The extremely high permeabilities of these membranes, combined with their small pore size will enable energy efficient filtration and eventually decrease the cost of water purification.[4pt] In collaboration with Francesco Fornasiero, Biosciences and Biotechnology Division, PLS, LLNL, Livermore, CA 94550; Sangil Kim, NSF Center for Biophotonics Science & Technology, University of California at Davis, Sacramento CA 95817; Jung Bin In, Mechanical Engineering Department, UC Berkeley, Berkeley CA 94720; Hyung Gyu Park, Jason K Holt, and Michael Stadermann, Biosciences and Biotechnology Division, PLS, LLNL; Costas P. Grigoropoulos, Mechanical Engineering Department, UC Berkeley; Aleksandr Noy, Biosciences and Biotechnology Division, PLS, LLNL and School of Natural Sciences, University of California at Merced.

  17. High-throughput Protein Purification and Quality Assessment for Crystallization

    PubMed Central

    Kim, Youngchang; Babnigg, Gyorgy; Jedrzejczak, Robert; Eschenfeldt, William H.; Li, Hui; Maltseva, Natalia; Hatzos-Skintges, Catherine; Gu, Minyi; Makowska-Grzyska, Magdalena; Wu, Ruiying; An, Hao; Chhor, Gekleng; Joachimiak, Andrzej

    2012-01-01

    The ultimate goal of structural biology is to understand the structural basis of proteins in cellular processes. In structural biology, the most critical issue is the availability of high-quality samples. “Structural biology-grade” proteins must be generated in the quantity and quality suitable for structure determination using X-ray crystallography or nuclear magnetic resonance (NMR) spectroscopy. The purification procedures must reproducibly yield homogeneous proteins or their derivatives containing marker atom(s) in milligram quantities. The choice of protein purification and handling procedures plays a critical role in obtaining high-quality protein samples. With structural genomics emphasizing a genome-based approach in understanding protein structure and function, a number of unique structures covering most of the protein folding space have been determined and new technologies with high efficiency have been developed. At the Midwest Center for Structural Genomics (MCSG), we have developed semi-automated protocols for high-throughput parallel protein expression and purification. A protein, expressed as a fusion with a cleavable affinity tag, is purified in two consecutive immobilized metal affinity chromatography (IMAC) steps: (i) the first step is an IMAC coupled with buffer-exchange, or size exclusion chromatography (IMAC-I), followed by the cleavage of the affinity tag using the highly specific Tobacco Etch Virus (TEV) protease; [1] the second step is IMAC and buffer exchange (IMAC-II) to remove the cleaved tag and tagged TEV protease. These protocols have been implemented on multidimensional chromatography workstations and, as we have shown, many proteins can be successfully produced in large-scale. All methods and protocols used for purification, some developed by MCSG, others adopted and integrated into the MCSG purification pipeline and more recently the Center for Structural Genomics of Infectious Diseases (CSGID) purification pipeline, are

  18. Recovery and purification process development for monoclonal antibody production

    PubMed Central

    Ma, Junfen; Winter, Charles; Bayer, Robert

    2010-01-01

    Hundreds of therapeutic monoclonal antibodies (mAbs) are currently in development, and many companies have multiple antibodies in their pipelines. Current methodology used in recovery processes for these molecules are reviewed here. Basic unit operations such as harvest, Protein A affinity chromatography and additional polishing steps are surveyed. Alternative processes such as flocculation, precipitation and membrane chromatography are discussed. We also cover platform approaches to purification methods development, use of high throughput screening methods, and offer a view on future developments in purification methodology as applied to mAbs. PMID:20647768

  19. Plant lipases: partial purification of Carica papaya lipase.

    PubMed

    Rivera, Ivanna; Mateos-Díaz, Juan Carlos; Sandoval, Georgina

    2012-01-01

    Lipases from plants have very interesting features for application in different fields. This chapter provides an overview on some of the most important aspects of plant lipases, such as sources, applications, physiological functions, and specificities. Lipases from laticifers and particularly Carica papaya lipase (CPL) have emerged as a versatile autoimmobilized biocatalyst. However, to get a better understanding of CPL biocatalytic properties, the isolation and purification of individual C. papaya lipolytic enzymes become necessary. In this chapter, a practical protocol for partial purification of the latex-associated lipolytic activity from C. papaya is given.

  20. High quality protein microarray using in situ protein purification

    PubMed Central

    Kwon, Keehwan; Grose, Carissa; Pieper, Rembert; Pandya, Gagan A; Fleischmann, Robert D; Peterson, Scott N

    2009-01-01

    Background In the postgenomic era, high throughput protein expression and protein microarray technologies have progressed markedly permitting screening of therapeutic reagents and discovery of novel protein functions. Hexa-histidine is one of the most commonly used fusion tags for protein expression due to its small size and convenient purification via immobilized metal ion affinity chromatography (IMAC). This purification process has been adapted to the protein microarray format, but the quality of in situ His-tagged protein purification on slides has not been systematically evaluated. We established methods to determine the level of purification of such proteins on metal chelate-modified slide surfaces. Optimized in situ purification of His-tagged recombinant proteins has the potential to become the new gold standard for cost-effective generation of high-quality and high-density protein microarrays. Results Two slide surfaces were examined, chelated Cu2+ slides suspended on a polyethylene glycol (PEG) coating and chelated Ni2+ slides immobilized on a support without PEG coating. Using PEG-coated chelated Cu2+ slides, consistently higher purities of recombinant proteins were measured. An optimized wash buffer (PBST) composed of 10 mM phosphate buffer, 2.7 mM KCl, 140 mM NaCl and 0.05% Tween 20, pH 7.4, further improved protein purity levels. Using Escherichia coli cell lysates expressing 90 recombinant Streptococcus pneumoniae proteins, 73 proteins were successfully immobilized, and 66 proteins were in situ purified with greater than 90% purity. We identified several antigens among the in situ-purified proteins via assays with anti-S. pneumoniae rabbit antibodies and a human patient antiserum, as a demonstration project of large scale microarray-based immunoproteomics profiling. The methodology is compatible with higher throughput formats of in vivo protein expression, eliminates the need for resin-based purification and circumvents protein solubility and

  1. Fundamental limitations in the purifications of tensor networks

    SciTech Connect

    De las Cuevas, G.; Cirac, J. I.; Cubitt, T. S.; Wolf, M. M.; Pérez-García, D.

    2016-07-15

    We show a fundamental limitation in the description of quantum many-body mixed states with tensor networks in purification form. Namely, we show that there exist mixed states which can be represented as a translationally invariant (TI) matrix product density operator valid for all system sizes, but for which there does not exist a TI purification valid for all system sizes. The proof is based on an undecidable problem and on the uniqueness of canonical forms of matrix product states. The result also holds for classical states.

  2. Isolation and purification of antigenic components of Cryptococcus.

    PubMed

    Wozniak, Karen L; Levitz, Stuart M

    2009-01-01

    The encapsulated fungal pathogens Cryptococcus neoformans and Cryptococcus gattii are significant agents of life-threatening infections, particularly in persons with suppressed cell-mediated immunity. This chapter provides detailed methodology for the purification of two of the major antigen fractions of C. neoformans: glucuronoxylomannan (GXM) and mannoprotein (MP). GXM is the primary component of the polysaccharide capsule, which is the major cryptococcal virulence factor. In contrast, MPs have been identified as key antigens that stimulate T-cell responses. Purification of GXM and MP should assist investigators studying the antigenic, biochemical, and virulence properties of Cryptococcus species.

  3. Expression and purification of recombinant nattokinase in Spodoptera frugiperda cells.

    PubMed

    Li, Xiaoxiang; Wang, Xiaoli; Xiong, Shaoling; Zhang, Jing; Cai, Litao; Yang, Yanyan

    2007-10-01

    A recombinant baculovirus, rv-egfp-NK, containing a reporter gene encoding the enhanced green fluorescent protein (EGFP), was used to express nattokinase (NK), a fibrinolytic enzyme, in Spodoptera frugiperda (SF-9) cells. The recombinant protein also included a histidine tag for purification using Ni(2+) resins. The recombinant NK, approximately 30 kDa, retained fibrinolytic activity (60 U/ml). The integration of the EGFP expression cassette in the Bac-to-Bac system is thus an effective method for the expression and purification of recombinant NK protein in Spodoptera frugiperda insect cells.

  4. Solid support resins and affinity purification mass spectrometry.

    PubMed

    Havis, Spencer; Moree, Wilna J; Mali, Sujina; Bark, Steven J

    2017-02-28

    Co-affinity purification-mass spectrometry (CoAP-MS) is a primary technology for elucidating the protein-protein interactions that form the basis of all biological processes. A critical component of CoAP-MS is the affinity purification (AP) of the bait protein, usually by immobilization of an antibody to a solid-phase resin. This Minireview discusses common resins, reagents, tagging methods, and their consideration for successful AP of tagged proteins. We discuss our experiences with different solid supports, their impact in AP experiments, and propose areas where chemistry can advance this important technology.

  5. High-throughput techniques for compound characterization and purification.

    PubMed

    Kyranos, J N; Cai, H; Zhang, B; Goetzinger, W K

    2001-11-01

    A new paradigm in drug discovery is the synthesis of structurally diverse collections of compounds, so-called libraries, followed by high-throughput biological screening. High-throughput characterization and purification techniques are required to provide high-quality compounds and reliable biological data, which has led to the development of faster methods, system automation and parallel approaches. This review summarizes recent advances in support of analytical characterization and preparative purification technologies. Notably, mass spectrometry (MS) and supercritical fluid chromatography (SFC) are among the areas where new developments have had a major impact on defining these high-throughput applications.

  6. Sandia Sodium Purification Loop (SNAPL) description and operations manual

    SciTech Connect

    Acton, R.U.; Weatherbee, R.L.; Smith, L.A.; Mastin, F.L.; Nowotny, K.E.

    1985-08-01

    Sandia's Sodium Purification Loop was constructed to purify sodium for fast reactor safety experiments. An oxide impurity of less than 10 parts per million is required by these in-pile experiments. Commercial, reactor grade sodium is purchased in 180 kg drums. The sodium is melted and transferred into the unit. The unit is of a loop design and purification is accomplished by ''cold trapping.'' Sodium purified in this loop has been chemically analysed at one part per million oxygen by weight. 5 refs., 22 figs., 7 tabs.

  7. Experimentally feasible purification of continuous-variable entanglement

    SciTech Connect

    Fiurasek, Jaromir; Filip, Radim; Marek, Petr; Schnabel, Roman

    2007-05-15

    We propose a scheme for purification and distillation of squeezed and entangled continuous-variable states of light transmitted through a channel exhibiting phase fluctuations. The outstanding advantage of the suggested protocol is its experimental feasibility since it only involves an interference of two copies of the decohered state on a balanced beam splitter, a homodyne measurement on one of the output beams, and a conditioning on the measurement outcome. The purification can counteract the detrimental effects of phase fluctuations in optical quantum-communication networks.

  8. Experimental Study on Purification of Low Grade Diatomite

    NASA Astrophysics Data System (ADS)

    Xiao, Liguang; Pang, Bo

    2017-04-01

    This paper presented an innovation for purification of low grade diatomite(DE) by grinding, ultrasonic pretreatment, acid leaching of closed stirring and calcination. The optimum process parameters of DE purification were obtained, the characterizations of original and purified DE were determined by SEM and BET. The results showed that the specific surface area of DE increased from 12.65m2/g to 23.23m2/g, which increased by 45.54%. SEM analysis revealed that the pore structure of purified DE was dredged highly.

  9. Determination of metal ions in biological purification of waste waters

    SciTech Connect

    Tikhomirova, L.N.; Spiridonova, N.N.; Mandzhgaladze, I.D.

    1994-12-01

    Chromium, nickel, copper, zinc, and manganese were determined in active sludge extracted for utilization from sewage purification works in biological purification of waste waters. The measurements were carried out by the atomic absorption method and with Merck colorimetric kits for rapid determination of metal ions. The results obtained by the rapid colorimetric method agree fairly well with those obtained by the atomic absorption method, which makes it possible to recommend rapid colorimetric methods for routine analysis of biological objects for the content of ions of heavy metals.

  10. Air pollution.

    PubMed

    Le, Nhu D; Sun, Li; Zidek, James V

    2010-01-01

    Toxic air pollutants are continuously released into the air supply. Various pollutants come from chemical facilities and small businesses, such as automobile service stations and dry cleaning establishments. Others, such as nitrogen oxides, carbon monoxide and other volatile organic chemicals, arise primarily from the incomplete combustion of fossil fuels (coal and petroleum) and are emitted from sources that include car exhausts, home heating and industrial power plants. Pollutants in the atmosphere also result from photochemical transformations; for example, ozone is formed when molecular oxygen or nitrogen interacts with ultraviolet radiation. An association between air pollution exposure and lung cancer has been observed in several studies. The evidence for other cancers is far less conclusive. Estimates of the population attributable risk of cancer has varied substantially over the last 40 years, reflecting the limitations of studies; these include insufficient information on confounders, difficulties in characterizing associations due to a likely lengthy latency interval, and exposure misclassification. Although earlier estimates were less than one percent, recent cohort studies that have taken into account some confounding factors, such as smoking and education amongst others, suggest that approximately 3.6% of lung cancer in the European Union could be due to air pollution exposure, particularly to sulphate and fine particulates. A separate cohort study estimated 5-7% of lung cancers in European never smokers and ex-smokers could be due to air pollution exposure. Therefore, while cigarette smoking remains the predominant risk factor, the proportion of lung cancers attributable to air pollution may be higher than previously thought. Overall, major weaknesses in all air-pollution-and-cancer studies to date have been inadequate characterization of long-term air pollution exposure and imprecise or no measurements of covariates. It has only been in the last

  11. Managing Air Quality - Air Pollutant Types

    EPA Pesticide Factsheets

    Describes the types of air pollutants, including common or criteria pollutants, and hazardous air pollutants and links to additional information. Also links to resources on other air pollution issues.

  12. Flue Gas Purification Utilizing SOx/NOx Reactions During Compression of CO{sub 2} Derived from Oxyfuel Combustion

    SciTech Connect

    Fogash, Kevin

    2010-09-30

    The United States wishes to decrease foreign energy dependence by utilizing the country’s significant coal reserves, while stemming the effects of global warming from greenhouse gases. In response to these needs, Air Products has developed a patented process for the compression and purification of the CO{sub 2} stream from oxyfuel combustion of pulverized coal. The purpose of this project was the development and performance of a comprehensive experimental and engineering evaluation to determine the feasibility of purifying CO{sub 2} derived from the flue gas generated in a tangentially fired coal combustion unit operated in the oxy-combustion mode. Following the design and construction of a 15 bar reactor system, Air Products conducted two test campaigns using the slip stream from the tangentially fired oxy-coal combustion unit. During the first test campaign, Air Products evaluated the reactor performance based on both the liquid and gaseous reactor effluents. The data obtained from the test run has enabled Air Products to determine the reaction and mass transfer rates, as well as the effectiveness of the reactor system. During the second test campaign, Air Products evaluated reactor performance based on effluents for different reactor pressures, as well as water recycle rates. Analysis of the reaction equations indicates that both pressure and water flow rate affect the process reaction rates, as well as the overall reactor performance.

  13. One-step purification of phosphinothricin acetyltransferase using reactive dye-affinity chromatography.

    PubMed

    Wang, Cunxi; Lee, Thomas C; Crowley, Kathleen S; Bell, Erin

    2015-01-01

    Reactive dye purification is an affinity purification technique offering unique selectivity and high purification potential. Historically, purification of phosphinothricin acetyltransferase (PAT) has involved several steps of precipitation and column chromatography. Here, we describe a novel purification method that is simple, time-saving, inexpensive, and reproducible. The novel method employs a single chromatography step using a reactive dye resin, Reactive brown 10-agarose. Reactive brown 10 preferentially binds the PAT protein, which can then be specifically released by one of its substrates, acetyl-CoA. Using Reactive brown 10-agarose, PAT protein can be purified to homogeneity from E. coli or plant tissue with high recovery efficiency.

  14. Cardiopulmonary Benefits of Reducing Indoor Particles of Outdoor Origin: a Randomized Double-Blind Crossover Trial of Air Purifiers

    PubMed Central

    Chen, Renjie; Zhao, Ang; Chen, Honglei; Zhao, Zhuohui; Cai, Jing; Wang, Cuicui; Yang, Changyuan; Li, Huichu; Xu, Xiaohui; Ha, Sandie; Li, Tiantian; Kan, Haidong

    2017-01-01

    Background Indoor exposure to fine particulate matter (PM2.5) from outdoor sources is a major health concern, especially in highly polluted developing countries, such as China. Few studies have evaluated the effectiveness of indoor air purification on the improvement of cardiopulmonary health in these areas. Objectives To evaluate whether a short-term indoor air purifier intervention improves cardiopulmonary health. Methods We conducted a randomized double-blind crossover trial among 35 healthy college students in Shanghai, China in 2014. These students lived in dormitories that were randomized into 2 groups and alternated the use of true or sham air purifiers for 48 h with a 2-week washout interval. We measured 14 circulating biomarkers of inflammation, coagulation and vasoconstriction, lung function, blood pressure (BP), and fractional exhaled nitric oxide (FeNO). We applied linear mixed-effect models to evaluate the effect of the intervention on health outcome variables. Results On average, air purification resulted in a 57% reduction in PM2.5 concentration from 96.2 to 41.3 μg/m3 within hours of operation. Air purification was significantly associated with decreases in geometric means of several circulating inflammatory and thrombogenic biomarkers, including 17.5% in monocyte chemoattractant protein-1, 68.1% in interleukin-1β, 32.8% in myeloperoxidase and 64.9% in soluble CD40 ligand. Further, systolic BP, diastolic BP, and FeNO were significantly decreased by 2.7%, 4.8%, and 17.0% in geometric mean, respectively. The impacts on lung function and vasoconstriction biomarkers were beneficial, but not statistically significant. Conclusion This intervention study demonstrated clear cardiopulmonary benefits of indoor air purification among young, healthy adults in a Chinese city with severe ambient particulate air pollution. (Intervention Study on the Health Impact of Air Filters in Chinese Adults; NCT02239744) PMID:26022815

  15. Effects of Humidity Swings on Adsorption Columns for Air Revitalization: Modeling and Experiments

    NASA Technical Reports Server (NTRS)

    LeVan, M. Douglas; Finn, John E.

    1997-01-01

    Air purification systems are necessary to provide clean air in the closed environments aboard spacecraft. Trace contaminants are removed using adsorption. One major factor concerning the removal of trace contaminants is relative humidity. Water can reduce adsorption capacity and, due to constant fluctuations, its presence is difficult to incorporate into adsorption column designs. The purpose of the research was to allow for better design techniques in trace contaminant adsorption systems, especially for feeds with water present. Experiments and mathematical modeling research on effects of humidity swings on adsorption columns for air revitalization were carried out.

  16. Healthy Air Outdoors

    MedlinePlus

    ... clean up the air are enforced. Learn more Climate Change Climate change threatens the health of millions of people, with ... What Makes Air Unhealthy Fighting for Healthy Air Climate Change Emergencies & Natural Disasters State of the Air Ask ...

  17. Air Quality System (AQS)

    EPA Pesticide Factsheets

    The Air Quality System (AQS) database contains measurements of air pollutant concentrations from throughout the United States and its territories. The measurements include both criteria air pollutants and hazardous air pollutants.

  18. Purification of lanthanides for double beta decay experiments

    SciTech Connect

    Polischuk, O. G.; Barabash, A. S.; Belli, P.; Bernabei, R.; Boiko, R. S.; Danevich, F. A.; Mokina, V. M.; Poda, D. V.; Tretyak, V. I.; Cappella, F.; Incicchitti, A.; Cerulli, R.; Laubenstein, M.; Nisi, S.

    2013-08-08

    There are several potentially double beta active isotopes among the lanthanide elements. However, even high purity grade lanthanide compounds contain {sup 238}U, {sup 226}Ra and {sup 232,228}Th typically on the level of ∼ (0.1 - 1) Bq/kg. The liquid-liquid extraction technique was used to remove traces of U, Ra and Th from CeO{sub 2}, Nd{sub 2}O{sub 3} and Gd{sub 2}O{sub 3}. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe γ spectrometry at the underground Gran Sasso National Laboratories of the INFN (Italy). After the purification the radioactive contamination of gadolinium oxide by Ra and Th was decreased at least one order of magnitude. The efficiency of the approach to purify cerium oxide from Ra was on same level, while the radioactive contamination of neodymium sample before and after the purification is below the sensitivity of analytical methods. The purification method is much less efficient for chemically very similar radioactive elements like lanthanum, lutetium and actinium. R and D of the methods to remove the pollutions with improved efficiency is in progress.

  19. [Isolation, screening and identification of yeast for aquaculture water purification].

    PubMed

    Xie, Fengxing; Zhang, Fengfeng; Zhou, Ke; Zhao, Yujie; Sun, Haibo; Wang, Yun

    2015-05-04

    In order to get excellent yeast strains for aquiculture water purification, we isolated, screened and identified yeasts from the aquacultural environment and intestinal tract of shrimp. The potential water purification ability of yeasts, isolated from the activated sludge of aquacultural environment and intestinal tract of white shrimp and mantis shrimp under normal and low temperature, was evaluated in the simulated wastewater. Morphological physio-biochemical characteristics, 5.8S rDNA ITS gene sequence analysis were used to identify the strains. Thirty-seven yeast strains were isolated from 3 samples, among them 16 strains were isolated under normal temperature (25 °C) while 21 strains were isolated under low temperature (15° C). Water purification test suggested 5 strains isolated under 25 °C and 6 strains isolated under 15 °C had higher removal ability of nitrite and ammonia from water. After 48 hours treatment with DN9 and CN6, 10.64 mg/L nitrite in the water was completely removed. After 96 hours treatment, CODcr degradation rates of the 2 strains were 52% and 67%, respectively. According to morphological, physio-biochemical characteristics and 5.8S rDNA ITS gene sequence analysis, the strain DN9 was identified as Rhodotorula mucilaginosa and CN6 as Rhodosporidium paludigenum. Strains DN9 and CN6 would be promising for water purification in aquiculture.

  20. Experimental studies on islets isolation, purification and function in rats.

    PubMed

    Pang, Xinlu; Xue, Wujun; Feng, Xinshun; Tian, Xiaohui; Teng, Yan; Ding, Xiaoming; Pan, Xiaoming; Guo, Qi; He, Xiaoli

    2015-01-01

    To develop a simple and effective method of islet isolation and purification in rats. Collagenase P was injected into pancreatic duct followed by incubation in water bath to digest the pancreas and isolate islet, then discontinuous gravity gradient purification was used to purify the islet. The purified islets were identified by dithizone staining. The viability of islets was assessed by fluorescence staining of acridine orange (AO) and propidium iodide (PI). The function of purified islets was determined by glucose-stimulated insulin release test and transplantation of rat with streptozocin-induced diabetes. 738±193 islets were recovered after purification. The average purity was 77±13%, the viability of islets was more than 95%. When inspected by glucose stimulation, the secreted insulin concentration was 24.31±5.47 mIU/L when stimulated by low concentration glucose and 37.62±4.29 mIU/L by high concentration glucose. There was significant difference between the two phases (P<0.05). The blood sugar concentration recovered to normal level after two days in the animals with islet transplantation. In conclusion, islets can be procured with good function and shape by using the method of injecting collagenase into pancreatic duct followed by incubation in water bath and purification using discontinuous gravity gradient.

  1. Methods in elastic tissue biology: elastin isolation and purification.

    PubMed

    Mecham, Robert P

    2008-05-01

    Elastin provides recoil to tissues subjected to repeated stretch, such as blood vessels and the lung. It is encoded by a single gene in mammals and is secreted as a 60-70 kDa monomer called tropoelastin. The functional form of the protein is that of a large, highly crosslinked polymer that organizes as sheets or fibers in the extracellular matrix. Purification of mature, crosslinked elastin is problematic because its insolubility precludes its isolation using standard wet-chemistry techniques. Instead, relatively harsh experimental approaches designed to remove non-elastin 'contaminates' are employed to generate an insoluble product that has the amino acid composition expected of elastin. Although soluble, tropoelastin also presents problems for isolation and purification. The protein's extreme stickiness and susceptibility to proteolysis requires careful attention during purification and in tropoelastin-based assays. This article describes the most common approaches for purification of insoluble elastin and tropoelastin. It also addresses key aspects of studying tropoelastin production in cultured cells, where elastin expression is highly dependent upon cell type, culture conditions, and passage number.

  2. Techniques for analysis and purification in high-throughput chemistry.

    PubMed

    Hughes, I; Hunter, D

    2001-06-01

    The success of combinatorial chemistry, and the increased emphasis on single well-characterised compounds of high purity, has had a significant impact on analytical and purification technologies. The requirement for ever-increasing throughput has led to the automation and parallelisation of these techniques. Advances have also been made in developing faster methods to augment throughput further.

  3. Purification and characterization of xylooligosaccharides (XOS) from Miscanthus x giganteus

    USDA-ARS?s Scientific Manuscript database

    Our previous investigation showed that xylooligosaccharides (XOS) could be produced effectively from Miscanthus x giganteus (MxG). Using autohydrolysis, an XOS yield of to 13.5% (w/w) of initial biomass and xylan yield of 69.2% (w/w) was observed. In this study, we investigated the purification of X...

  4. Purification of boron nitride nanotubes via polymer wrapping

    SciTech Connect

    Choi, Jin-Hyuk; Kim, Jaewoo; Seo, Duckbong; Seo, Young-Soo

    2013-03-15

    Highlights: ► Surface modification of boron nitride nanotubes using polymeric materials. ► Surface-modified BNNT was purified with a simple dilution-centrifugation step. ► Surface-modified BNNT can be directly used for polymer composite fabrication ► Degree of purification was analyzed by Raman spectroscopy. - Abstract: Boron nitride nanotubes (BNNT) synthesized by a ball milling-annealing were surface-modified using three different types of polymeric materials. Those materials were chosen depending on future applications especially in polymer nanocomposite fabrications. We found that the surface-modified BNNT can be purified with a simple dilution-centrifugation step, which would be suitable for large-scale purification. Degree of purification was monitored by means of the center peak position and FWHM of E{sub 2g} mode of BNNT in Raman spectra. As the purification of BNNT develops, the peak position was up-shifted while FWHM of the peak was narrowed.

  5. Purification of KamLAND-Zen liquid scintillator

    SciTech Connect

    Ikeda, Haruo

    2013-08-08

    KamLAND-Zen is neutrino-less double-beta decay search experiment using enriched 300 kg of {sup 136}Xe dissolved in pure liquid scintillator. This report is purification work of liquid scintillator for KamLAND-Zen experiment before installation in the inner-balloon and background rejection processes after installation.

  6. Ligand-modified metal clusters for gas separation and purification

    DOEpatents

    Okrut, Alexander; Ouyang, Xiaoying; Runnebaum, Ron; Gates, Bruce C.; Katz, Alexander

    2017-02-21

    Provided is an organic ligand-bound metal surface that selects one gaseous species over another. The species can be closely sized molecular species having less than 1 Angstrom difference in kinetic diameter. In one embodiment, the species comprise carbon monoxide and ethylene. Such organic ligand-bound metal surfaces can be successfully used in gas phase separations or purifications, sensing, and in catalysis.

  7. Purification the surface of detail from biological contaminations

    NASA Astrophysics Data System (ADS)

    Gabdrakhmanov, Az T.; Israphilov, I. H.; Galiakbarov, A. T.; Gabdrakhmanov, Al T.

    2017-01-01

    More than 70% of biodegradation occur due to the corrosion processes. A biological corrosion causes the greatest damage to the oil and gas-production industry, the Navy and pipelines, constructions of water supply, means of communication. This paper proposes an effective method of purification various surfaces from biological contaminations by using of cold plasma.

  8. Experimental studies on islets isolation, purification and function in rats

    PubMed Central

    Pang, Xinlu; Xue, Wujun; Feng, Xinshun; Tian, Xiaohui; Teng, Yan; Ding, Xiaoming; Pan, Xiaoming; Guo, Qi; He, Xiaoli

    2015-01-01

    To develop a simple and effective method of islet isolation and purification in rats. Collagenase P was injected into pancreatic duct followed by incubation in water bath to digest the pancreas and isolate islet, then discontinuous gravity gradient purification was used to purify the islet. The purified islets were identified by dithizone staining. The viability of islets was assessed by fluorescence staining of acridine orange (AO) and propidium iodide (PI). The function of purified islets was determined by glucose-stimulated insulin release test and transplantation of rat with streptozocin-induced diabetes. 738±193 islets were recovered after purification. The average purity was 77±13%, the viability of islets was more than 95%. When inspected by glucose stimulation, the secreted insulin concentration was 24.31±5.47 mIU/L when stimulated by low concentration glucose and 37.62±4.29 mIU/L by high concentration glucose. There was significant difference between the two phases (P<0.05). The blood sugar concentration recovered to normal level after two days in the animals with islet transplantation. In conclusion, islets can be procured with good function and shape by using the method of injecting collagenase into pancreatic duct followed by incubation in water bath and purification using discontinuous gravity gradient. PMID:26885021

  9. Electrophoretic cell separation using microspheres. [purification of lymphocytes

    NASA Technical Reports Server (NTRS)

    Smolka, A.; Sachs, G.

    1980-01-01

    Methods of cell separation based on the electrokinetic properties of the cell membrane offer a degree of discrimination among cell populations which is not available with methods based on cell size or density alone. Studies aimed at extending red cell separations using microspheres to purification of lymphocytes.

  10. The Partial Purification and Characterization of Lactate Dehydrogenase.

    ERIC Educational Resources Information Center

    Wolf, Edward C.

    1988-01-01

    Offers several advantages over other possibilities as the enzyme of choice for a student's first exposure to a purification scheme. Uses equipment and materials normally found in biochemistry laboratories. Incorporates several important biochemical techniques including spectrophotometry, chromatography, centrifugation, and electrophoresis. (MVL)

  11. ENDONUCLEASE II OF E. coli, I. ISOLATION AND PURIFICATION*

    PubMed Central

    Friedberg, Errol C.; Goldthwait, David A.

    1969-01-01

    The isolation and purification of a new endonuclease of E. coli is described. This enzyme degrades alkylated DNA as assayed by a technique that requires double-strand scission. The enzyme also makes a limited number of single-strand breaks in native nonalkylated DNA. PMID:4895219

  12. Extraction, Purification, and Spectroscopic Characterization of a Mixture of Capsaicinoids

    ERIC Educational Resources Information Center

    Wagner, Carl E.; Cahill, Thomas M.; Marshall, Pamela A.

    2011-01-01

    This laboratory experiment provides a safe and effective way to instruct undergraduate organic chemistry students about natural-product extraction, purification, and NMR spectroscopic characterization. On the first day, students extract dried habanero peppers with toluene, perform a pipet silica gel column to separate carotenoids from…

  13. 2D nanostructures for water purification: graphene and beyond.

    PubMed

    Dervin, Saoirse; Dionysiou, Dionysios D; Pillai, Suresh C

    2016-08-18

    Owing to their atomically thin structure, large surface area and mechanical strength, 2D nanoporous materials are considered to be suitable alternatives for existing desalination and water purification membrane materials. Recent progress in the development of nanoporous graphene based materials has generated enormous potential for water purification technologies. Progress in the development of nanoporous graphene and graphene oxide (GO) membranes, the mechanism of graphene molecular sieve action, structural design, hydrophilic nature, mechanical strength and antifouling properties and the principal challenges associated with nanopore generation are discussed in detail. Subsequently, the recent applications and performance of newly developed 2D materials such as 2D boron nitride (BN) nanosheets, graphyne, molybdenum disulfide (MoS2), tungsten chalcogenides (WS2) and titanium carbide (Ti3C2Tx) are highlighted. In addition, the challenges affecting 2D nanostructures for water purification are highlighted and their applications in the water purification industry are discussed. Though only a few 2D materials have been explored so far for water treatment applications, this emerging field of research is set to attract a great deal of attention in the near future.

  14. Advanced purification of petroleum refinery wastewater by catalytic vacuum distillation.

    PubMed

    Yan, Long; Ma, Hongzhu; Wang, Bo; Mao, Wei; Chen, Yashao

    2010-06-15

    In our work, a new process, catalytic vacuum distillation (CVD) was utilized for purification of petroleum refinery wastewater that was characteristic of high chemical oxygen demand (COD) and salinity. Moreover, various common promoters, like FeCl(3), kaolin, H(2)SO(4) and NaOH were investigated to improve the purification efficiency of CVD. Here, the purification efficiency was estimated by COD testing, electrolytic conductivity, UV-vis spectrum, gas chromatography-mass spectrometry (GC-MS) and pH value. The results showed that NaOH promoted CVD displayed higher efficiency in purification of refinery wastewater than other systems, where the pellucid effluents with low salinity and high COD removal efficiency (99%) were obtained after treatment, and the corresponding pH values of effluents varied from 7 to 9. Furthermore, environment estimation was also tested and the results showed that the effluent had no influence on plant growth. Thus, based on satisfied removal efficiency of COD and salinity achieved simultaneously, NaOH promoted CVD process is an effective approach to purify petroleum refinery wastewater. Copyright 2010 Elsevier B.V. All rights reserved.

  15. Fast and efficient protein purification using membrane adsorber systems.

    PubMed

    Suck, Kirstin; Walter, Johanna; Menzel, Frauke; Tappe, Alexander; Kasper, Cornelia; Naumann, Claudia; Zeidler, Robert; Scheper, Thomas

    2006-02-10

    The purification of proteins from complex cell culture samples is an essential step in proteomic research. Traditional chromatographic methods often require several steps resulting in time consuming and costly procedures. In contrast, protein purification via membrane adsorbers offers the advantage of fast and gentle but still effective isolation. In this work, we present a new method for purification of proteins from crude cell extracts via membrane adsorber based devices. This isolation procedure utilises the membranes favourable pore structure allowing high flow rates without causing high back pressure. Therefore, shear stress to fragile structures is avoided. In addition, mass transfer takes place through convection rather than diffusion, thus allowing very rapid separation processes. Based on this membrane adsorber technology the separation of two model proteins, human serum albumin (HSA) and immungluboline G (IgG) is shown. The isolation of human growth hormone (hGH) from chinese hamster ovary (CHO) cell culture supernatant was performed using a cation exchange membrane. The isolation of the enzyme penicillin acylase from the crude Escherichia coli supernatant was achieved using an anion exchange spin column within one step at a considerable purity. In summary, the membrane adsorber devices have proven to be suitable tools for the purification of proteins from different complex cell culture samples.

  16. PURIFICATION AND CHARACTERISATION OF A FUNGAL Beta-MANNANASE,

    DTIC Science & Technology

    A mannanase from ’ Cellulase 36’, a commercial preparation of Aspergillus enzymes, has been purified and characterised. The purified enzyme contains...traces of cellulase and laminarinase activities. The purification factor is 61 and the enzyme yield 11%. The molecular weight was determined. A

  17. Purification of lanthanides for double beta decay experiments

    NASA Astrophysics Data System (ADS)

    Polischuk, O. G.; Barabash, A. S.; Belli, P.; Bernabei, R.; Boiko, R. S.; Cappella, F.; Cerulli, R.; Danevich, F. A.; Incicchitti, A.; Laubenstein, M.; Mokina, V. M.; Nisi, S.; Poda, D. V.; Tretyak, V. I.

    2013-08-01

    There are several potentially double beta active isotopes among the lanthanide elements. However, even high purity grade lanthanide compounds contain 238U, 226Ra and 232,228Th typically on the level of ˜ (0.1 - 1) Bq/kg. The liquid-liquid extraction technique was used to remove traces of U, Ra and Th from CeO2, Nd2O3 and Gd2O3. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe γ spectrometry at the underground Gran Sasso National Laboratories of the INFN (Italy). After the purification the radioactive contamination of gadolinium oxide by Ra and Th was decreased at least one order of magnitude. The efficiency of the approach to purify cerium oxide from Ra was on same level, while the radioactive contamination of neodymium sample before and after the purification is below the sensitivity of analytical methods. The purification method is much less efficient for chemically very similar radioactive elements like lanthanum, lutetium and actinium. R&D of the methods to remove the pollutions with improved efficiency is in progress.

  18. Electrophoretic High Molecular Weight DNA Purification Enables Optical Mapping

    PubMed Central

    Maydan, Jason; Thomas, Matthew; Tabanfar, Leyla; Mai, Laura; Poon, Hau-Ling; Pe, Joel; Hahn, Kristen; Goji, Noriko; Amoako, Kingsley; Marziali, Andre; Hanson, Dan

    2013-01-01

    Optical mapping generates an ordered restriction map from single, long DNA molecules. By overlapping restriction maps from multiple molecules, a physical map of entire chromosomes and genomes is constructed, greatly facilitating genome assembly in next generation sequencing projects, comparative genomics and strain typing. However, optical mapping relies on a method of preparing high quality DNA >250 kb in length, which can be challenging from some organisms and sample types. Here we demonstrate the ability of Boreal Genomics' Aurora instrument to provide pure, high molecular weight (HMW) DNA 250-1,100 kb in length, ideally suited for optical mapping. The Aurora performs electrophoretic DNA purification within an agarose gel in reusable cartridges, protecting long DNA molecules from shearing forces associated with liquid handling steps common to other purification methods. DNA can be purified directly from intact cells embedded and lysed within an agarose gel, preserving the highest molecular weight DNA possible while achieving exceptional levels of purity. The Aurora delivers DNA in a buffer solution, where DNA can be condensed and protected from shearing during recovery with a pipette. DNA is then returned to its regular coiled state by simple dilution prior to optical mapping. Here we present images showing HMW DNA purification taking place in the Aurora and subsequent images of single DNA molecules on OpGen's Argus® Optical Mapping System. Future work will focus on further optimizing Aurora HMW DNA purification to bias DNA recovery in favor of only the longest molecules in a sample, maximizing the benefits of optical mapping.

  19. Ice-shell purification of ice-binding proteins.

    PubMed

    Marshall, Craig J; Basu, Koli; Davies, Peter L

    2016-06-01

    Ice-affinity purification is a simple and efficient method of purifying to homogeneity both natural and recombinant ice-binding proteins. The purification involves the incorporation of ice-binding proteins into slowly-growing ice and the exclusion of other proteins and solutes. In previous approaches, the ice was grown around a hollow brass finger through which coolant was circulated. We describe here an easily-constructed apparatus that employs ice affinity purification that not only shortens the time for purification from 1-2 days to 1-2 h, but also enhances yield and purity. In this apparatus, the surface area for the separation was increased by extracting the ice-binding proteins into an ice-shell formed inside a rotating round-bottom flask partially submerged in a sub-zero bath. In principle, any ice-binding compound can be recovered from liquid solution, and the method is readily scalable. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Zein purification: the process, the product, market potential

    USDA-ARS?s Scientific Manuscript database

    The objectives of this article intend to give an overview of a zein purification, decolorization and deodorization process, methodologies to assess those properties and applications of the purified product. The process involves column filtration of commercial zein solutions through a combination of ...

  1. Purification of cytochrome c oxidase by lysine-affinity chromatography.

    PubMed

    Felsch, J; Kotake, S; Copeland, R A

    1992-02-01

    A method for the purification of cytochrome c oxidase that is based on the affinity of this enzyme for polycations such as poly-L-lysine is described. When detergent extracts of bovine cardiac mitochondria were applied to either a poly-L-lysine-agarose or a lysine-Sepharose column at low ionic strength, cytochrome c oxidase was found to adhere tightly, whereas the bulk of the proteins were eluted by washing with the same buffer. The cytochrome c oxidase was eluted by application of a linear potassium chloride gradient to the columns. The resulting enzyme was identical to that obtained by more traditional purification methods in terms of its subunit composition, optical and resonance Raman spectra, and cytochrome c oxidizing activity. When detergent extracts of spheroplasts from Paracoccus denitrificans were applied to these columns, the cytochrome c oxidase from this organism was also found to adhere tightly. Thus this purification method appears applicable to both prokaryotic and eukaryotic forms of the enzyme. The advantages of this new purification method are that it is less labor intensive than the traditional procedure and less expensive than methods based on cytochrome c-affinity chromatography.

  2. Preparation and Purification of Multigram Quantities of TAX and SEX.

    DTIC Science & Technology

    1981-12-01

    of Improved Continuous-Flow Miniplant for Multikilogram Synthesis of TAX ................................... 12 2 Purification of TAX by Preparative...JacketTCO (65-700F) Water Bath (55-gal drum) Evolution Coil _L__in2 1IUR SCHEMATIC OF IMPROVED CONTINUOUS-FLOW MINIPLANT FOR MULTIKILOGRAM SYNTHESIS OF

  3. Purification of phlorotannins from Macrocystis pyrifera using macroporous resins.

    PubMed

    Leyton, A; Vergara-Salinas, J R; Pérez-Correa, J R; Lienqueo, M E

    2017-12-15

    Phlorotannins are secondary metabolites produced by brown seaweed, which are known for their nutraceutical and pharmacological properties. The aim of this work was to determine the type of macroporous resin and the conditions of operation that improve the purification of phlorotannins extracted from brown seaweed, Macrocystis pyrifera. For the purification of phlorotannins, six resins (HP-20, SP-850, XAD-7, XAD-16N, XAD-4 and XAD-2) were assessed. The kinetic adsorption allowed determination of an average adsorption time for the resins of 9h. The highest level of purification of phlorotannins was obtained with XAD-16N, 42%, with an adsorption capacity of 183±18mgPGE/g resin, and a desorption ratio of 38.2±7.7%. According to the adsorption isotherm the best temperature of operation was 25°C, and the model that best described the adsorption properties was the Freundlich model. The purification of phlorotannins might expand their use as a bioactive substance in the food, nutraceutical and pharmaceutical industries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. The Partial Purification and Characterization of Lactate Dehydrogenase.

    ERIC Educational Resources Information Center

    Wolf, Edward C.

    1988-01-01

    Offers several advantages over other possibilities as the enzyme of choice for a student's first exposure to a purification scheme. Uses equipment and materials normally found in biochemistry laboratories. Incorporates several important biochemical techniques including spectrophotometry, chromatography, centrifugation, and electrophoresis. (MVL)

  5. An improved purification procedure for Leishmania RNA virus (LRV)

    PubMed Central

    de Souza, Marcos Michel; Manzine, Livia Regina; da Silva, Marcos Vinicius G.; Bettini, Jefferson; Portugal, Rodrigo Vilares; Cruz, Angela Kaysel; Arruda, Eurico; Thiemann, Otavio Henrique

    2014-01-01

    Leishmania RNA Virus (LRV, Totiviridae) infect Leishmania cells and subvert mice immune response, probably promoting parasite persistence, suggesting significant roles for LRV in host-parasite interaction. Here we describe a new LRV1-4 purification protocol, enabling capsid visualization by negatively stained electron microscopy representing a significant contribution to future LRV investigations. PMID:25242960

  6. An improved purification procedure for Leishmania RNA virus (LRV).

    PubMed

    de Souza, Marcos Michel; Manzine, Livia Regina; da Silva, Marcos Vinicius G; Bettini, Jefferson; Portugal, Rodrigo Vilares; Cruz, Angela Kaysel; Arruda, Eurico; Thiemann, Otavio Henrique

    2014-01-01

    Leishmania RNA Virus (LRV, Totiviridae) infect Leishmania cells and subvert mice immune response, probably promoting parasite persistence, suggesting significant roles for LRV in host-parasite interaction. Here we describe a new LRV1-4 purification protocol, enabling capsid visualization by negatively stained electron microscopy representing a significant contribution to future LRV investigations.

  7. Modified cationic membranes for water purification, and their selective permeability

    NASA Astrophysics Data System (ADS)

    Mavrin, G. V.; Fasullin, D. D.; Melkolvan, R. G.

    2014-12-01

    Wastewater containing heavy metal ions pose a significant toxicological risk to aquatic ecosystems and humans. The common problem of modern engineering technology is the development of environmentally friendly systems with a closed-circuit and a minimum waste. The ion exchange membrane can significantly reduce the cost of wastewater treatment and provide a high degree of purification.

  8. Optimiziing the laboratory monitoring of biological wastewater-purification systems

    SciTech Connect

    S.V. Gerasimov

    2009-05-15

    Optimization of the laboratory monitoring of biochemical wastewater-treatment systems at coke plants is considered, for the example of OAO Koks. By adopting a methodological approach to determine the necessary data from chemical analysis, it is possible to reduce the time, labor, and materials required for monitoring, without impairing the purification process or compromising the plant's environmental policies.

  9. Purification of a rat neurotensin receptor expressed in Escherichia coli.

    PubMed Central

    Tucker, J; Grisshammer, R

    1996-01-01

    A truncated rat neurotensin receptor (NTR), expressed in Escherichia coli with the maltose-binding protein fused to its N-terminus and the 13 amino acid Bio tag fused to its C-terminus, was purified to apparent homogeneity in two steps by use of the monomeric avidin system followed by a novel neurotensin column. This purification protocol was developed by engineering a variety of affinity tags on to the C-terminus of NTR. Surprisingly, expression levels varied considerably depending on the C-terminal tag used. Functional expression of NTR was highest (800 receptors/cell) when thioredoxin was placed between the receptor C-terminus and the tag, indicating a stabilizing effect of the thioredoxin moiety. Several affinity chromatography methods were tested for purification. NTR with the in vivo-biotinylated Bio tag was purified with the highest efficiency compared with NTR with the Strep tag or a hexa-histidine tail. Co-expression of biotin ligase improved considerably the in vivo biotinylation of the Bio tag and, therefore, the overall purification yield. Proteolysis of the NTR fusion protein was prevented by removing a protease-sensitive site discovered at the N-terminus of NTR. The ligand binding properties of the purified receptor were similar to those of the membrane-bound protein and the native receptor. The scale-up of this purification scheme, to provide sufficient protein for biophysical studies, is in progress. PMID:8760379

  10. Purification of Organic Materials and Study of Polymers Therefrom.

    DTIC Science & Technology

    1966-06-01

    the purification of adipic acid and hexamethylenediamine and the study of the effects of high monomer purity on the properties of nylon 66. The...properties of a standard grade nylon prepared from high quality commercial adipic acid and distilled hexamethylenediamine were compared with a nylon obtained

  11. Extraction, Purification, and Spectroscopic Characterization of a Mixture of Capsaicinoids

    ERIC Educational Resources Information Center

    Wagner, Carl E.; Cahill, Thomas M.; Marshall, Pamela A.

    2011-01-01

    This laboratory experiment provides a safe and effective way to instruct undergraduate organic chemistry students about natural-product extraction, purification, and NMR spectroscopic characterization. On the first day, students extract dried habanero peppers with toluene, perform a pipet silica gel column to separate carotenoids from…

  12. Synthesis, purification, and acyl migration kinetics of 2-Monoricinoleoylglycerol

    USDA-ARS?s Scientific Manuscript database

    2-Monoricinoleoylglycerol (2-MRG) was synthesized by the conventional enzymatic ethanolysis of castor oil. Due to the fatty acid C12-OH group, conventional liquid-liquid extraction methods developed for less polar, non-hydroxylated 2-monoacylglycerols (2-MAG) proved inadequate for 2-MRG purification...

  13. Turnkey Helium Purification and Liquefaction Plant for DARWIN, Australia

    NASA Astrophysics Data System (ADS)

    Lindemann, U.; Boeck, S.; Blum, L.; Kurtcuoglu, K.

    2010-04-01

    The Linde Group, through its Australian subsidiary BOC Limited, has signed an agreement with Darwin LNG Pty Ltd for the supply of feed-gas to Linde's new helium refining and liquefaction facility in Darwin, Australia. Linde Kryotechnik AG, located in Switzerland, has carried out the engineering and fabrication of the equipment for the turn key helium plant. The raw feed gas flow of 20'730 Nm3/h contains up to of 3 mol% helium. The purification process of the feed gas consists of partial condensation of nitrogen in two stages, cryogenic adsorption and finally catalytic oxidation of hydrogen followed by a dryer system. Downstream of the purification the refined helium is liquefied using a modified Bryton process and stored in a 30'000 gal LHe tank. For further distribution and export of the liquid helium there are two stations available for filling of truck trailers and containers. The liquid nitrogen, required for refrigeration capacity to the nitrogen removal stages in the purification process as well as for the pre-cooling of the pure helium in the liquefaction process, is generated on site during the feed gas purification process. The optimized process provides low power consumption, maximum helium recovery and a minimum helium loss.

  14. 21 CFR 876.5665 - Water purification system for hemodialysis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Water purification system for hemodialysis. 876.5665 Section 876.5665 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5665 Water...

  15. 21 CFR 876.5665 - Water purification system for hemodialysis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Water purification system for hemodialysis. 876.5665 Section 876.5665 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5665 Water...

  16. Purification of gibberellin sub 53 -oxidase from spinach

    SciTech Connect

    Wilson, T.M.; Zeevaart, J.A.D. )

    1989-04-01

    Spinach is a long-day rosette plants, in which stem growth is mediated by gibberellins. It has been shown that two enzymatic steps, GA{sub 53}-oxidase and GA{sub 19}-oxidase, are controlled by light. To develop an understanding into this light regulation, purification of GA{sub 53}-oxidase has been undertaken. The original assay relied on the HPLC separation of the product and substrate, but was considered too slow for the development of a purification scheme. A TLC system was developed which in conjunction with improvements to the assay conditions was sensitive and gave rapid results. The partial purification of the GA{sub 53}-oxidase is achieved by a high speed centrifugation, 40-55% ammonium sulfate precipitation, an hydroxyapatite column, Sephadex G-100 column and an anion exchange FPLC column, Mono Q HR10/10, yielding 1000-fold purification and 15% recovery. Monoclonal antibodies to the protein will be raised and used to further characterize the enzyme.

  17. Use and application of hydrophobic interaction chromatography for protein purification.

    PubMed

    McCue, Justin T

    2014-01-01

    The objective of this section is to provide the reader with guidelines and background on the use and experimental application of Hydrophobic Interaction chromatography (HIC) for the purification of proteins. The section will give step by step instructions on how to use HIC in the laboratory to purify proteins. General guidelines and relevant background information is also provided.

  18. Characterization of anaerobic sulfite reduction by Salmonella typhimurium and purification of the anaerobically induced sulfite reductase

    SciTech Connect

    Hallenbeck, P.C. ); Clark, M.A.; Barrett, E.L. )

    1989-06-01

    Mutants of Salmonella typhimurium that lack the biosynthetic sulfite reductase (cysI and cysJ mutants) retain the ability to reduce sulfite for growth under anaerobic conditions. Here we report studies of sulfite reduction by a cysI mutant of S. typhimurium and purification of the associated anaerobic sulfite reductase. Sulfite reduction for anaerobic growth did not require a reducing atmosphere but was prevented by an argon atmosphere contaminated with air (<0.33%). It was also prevented by the presence of 0.1 mM nitrate. Anaerobic growth in liquid minimal medium, but not on agar, was found to require additions of trace amounts (10{sup {minus}7} M) of cysteine. Spontaneous mutants that grew under the argon contaminated with air also lost the requirement for 10{sup {minus}7}M cysteine for anaerobic growth in liquid. A role for sulfite reduction in anaerobic energy generation was contraindicated by the findings that sulfite reduction did not improve cell yields, and anaerobic sulfite reductase activity was greatest during the stationary phase of growth. Sulfite reductase was purified from the cytoplasmic fraction of the anaerobically grown cysI mutant and was purified 190-fold. The most effective donor in crude extracts was NADH. NADHP and methyl viologen were, respectively, 40 and 30% as effective as NADH. Oxygen reversibly inhibited the enzyme. The anaerobic sulfite reductase showed some resemblance to the biosynthetic sulfite reductase, but apparently it has a unique, as yet unidentified function.

  19. Ambient Air

    EPA Pesticide Factsheets

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  20. Purification Effect of Areca Palm for Continuously Emitting Formaldehyde in a Real Office Environment

    NASA Astrophysics Data System (ADS)

    Sawada, Ayako; Oyabu, Takashi; Takenaka, Kozaburo; Yoshida, Taketoshi

    Plant air-purification effect to reduce formaldehyde in a real office environment was examined. A potted Areca palm (height: about 2m) was adopted as a subjective plant. Plant purification effect was evaluated using a tin oxide gas sensor and a commercial tool for formaldehyde measurement was also used. The effect became higher as the atmospheric formaldehyde concentration was higher. The concentration became lower as the plants were installed. The effect did not greatly increase when the number of the installed pots was increased to seven from four. Concentration of carbon dioxide increased up to 450ppm by placing the pots at night. It is, however, below the regulated value (1000ppm) of Japan building managing law. Light intensity in the room fluctuated periodically and the carbon dioxide concentration changed periodically according to the fluctuation of light intensity from outside. There was a negative correlation between their characteristics. When the characteristic of carbon dioxide concentration was shifted forward by 1 hour with respect to the light intensity characteristic, the maximum value of correlation coefficient was obtained to be about -0.9. An integration value of a sensor output curve with time after the setting of potted plants could be regarded as a measure of an exposure volume of the plants to formaldehyde. The exposure value was found to become smaller as the number of the plants increased. In the experiment, formaldehyde was emitted continuously and the atmospheric concentration was kept at about 0.3ppm and the value was decreased to about 0.1ppm by the potted plants. This is close to the regulated value of 0.08ppm by WHO.

  1. Automated high-throughput protein purification using an ÄKTApurifier and a CETAC autosampler.

    PubMed

    Yoo, Daniel; Provchy, Justin; Park, Cynthia; Schulz, Craig; Walker, Kenneth

    2014-05-30

    As the pace of drug discovery accelerates there is an increased focus on screening larger numbers of protein therapeutic candidates to identify those that are functionally superior and to assess manufacturability earlier in the process. Although there have been advances toward high throughput (HT) cloning and expression, protein purification is still an area where improvements can be made to conventional techniques. Current methodologies for purification often involve a tradeoff between HT automation or capacity and quality. We present an ÄKTA combined with an autosampler, the ÄKTA-AS, which has the capability of purifying up to 240 samples in two chromatographic dimensions without the need for user intervention. The ÄKTA-AS has been shown to be reliable with sample volumes between 0.5 mL and 100 mL, and the innovative use of a uniquely configured loading valve ensures reliability by efficiently removing air from the system as well as preventing sample cross contamination. Incorporation of a sample pump flush minimizes sample loss and enables recoveries ranging from the low tens of micrograms to milligram quantities of protein. In addition, when used in an affinity capture-buffer exchange format the final samples are formulated in a buffer compatible with most assays without requirement of additional downstream processing. The system is designed to capture samples in 96-well microplate format allowing for seamless integration of downstream HT analytic processes such as microfluidic or HPLC analysis. Most notably, there is minimal operator intervention to operate this system, thereby increasing efficiency, sample consistency and reducing the risk of human error.

  2. Purification of crime scene DNA extracts using centrifugal filter devices

    PubMed Central

    2013-01-01

    Background The success of forensic DNA analysis is limited by the size, quality and purity of biological evidence found at crime scenes. Sample impurities can inhibit PCR, resulting in partial or negative DNA profiles. Various DNA purification methods are applied to remove impurities, for example, employing centrifugal filter devices. However, irrespective of method, DNA purification leads to DNA loss. Here we evaluate the filter devices Amicon Ultra 30 K and Microsep 30 K with respect to recovery rate and general performance for various types of PCR-inhibitory crime scene samples. Methods Recovery rates for DNA purification using Amicon Ultra 30 K and Microsep 30 K were gathered using quantitative PCR. Mock crime scene DNA extracts were analyzed using quantitative PCR and short tandem repeat (STR) profiling to test the general performance and inhibitor-removal properties of the two filter devices. Additionally, the outcome of long-term routine casework DNA analysis applying each of the devices was evaluated. Results Applying Microsep 30 K, 14 to 32% of the input DNA was recovered, whereas Amicon Ultra 30 K retained 62 to 70% of the DNA. The improved purity following filter purification counteracted some of this DNA loss, leading to slightly increased electropherogram peak heights for blood on denim (Amicon Ultra 30 K and Microsep 30 K) and saliva on envelope (Amicon Ultra 30 K). Comparing Amicon Ultra 30 K and Microsep 30 K for purification of DNA extracts from mock crime scene samples, the former generated significantly higher peak heights for rape case samples (P-values <0.01) and for hairs (P-values <0.036). In long-term routine use of the two filter devices, DNA extracts purified with Amicon Ultra 30 K were considerably less PCR-inhibitory in Quantifiler Human qPCR analysis compared to Microsep 30 K. Conclusions Amicon Ultra 30 K performed better than Microsep 30 K due to higher DNA recovery and more efficient removal of PCR-inhibitory substances. The

  3. Purification of crime scene DNA extracts using centrifugal filter devices.

    PubMed

    Norén, Lina; Hedell, Ronny; Ansell, Ricky; Hedman, Johannes

    2013-04-24

    The success of forensic DNA analysis is limited by the size, quality and purity of biological evidence found at crime scenes. Sample impurities can inhibit PCR, resulting in partial or negative DNA profiles. Various DNA purification methods are applied to remove impurities, for example, employing centrifugal filter devices. However, irrespective of method, DNA purification leads to DNA loss. Here we evaluate the filter devices Amicon Ultra 30 K and Microsep 30 K with respect to recovery rate and general performance for various types of PCR-inhibitory crime scene samples. Recovery rates for DNA purification using Amicon Ultra 30 K and Microsep 30 K were gathered using quantitative PCR. Mock crime scene DNA extracts were analyzed using quantitative PCR and short tandem repeat (STR) profiling to test the general performance and inhibitor-removal properties of the two filter devices. Additionally, the outcome of long-term routine casework DNA analysis applying each of the devices was evaluated. Applying Microsep 30 K, 14 to 32% of the input DNA was recovered, whereas Amicon Ultra 30 K retained 62 to 70% of the DNA. The improved purity following filter purification counteracted some of this DNA loss, leading to slightly increased electropherogram peak heights for blood on denim (Amicon Ultra 30 K and Microsep 30 K) and saliva on envelope (Amicon Ultra 30 K). Comparing Amicon Ultra 30 K and Microsep 30 K for purification of DNA extracts from mock crime scene samples, the former generated significantly higher peak heights for rape case samples (P-values <0.01) and for hairs (P-values <0.036). In long-term routine use of the two filter devices, DNA extracts purified with Amicon Ultra 30 K were considerably less PCR-inhibitory in Quantifiler Human qPCR analysis compared to Microsep 30 K. Amicon Ultra 30 K performed better than Microsep 30 K due to higher DNA recovery and more efficient removal of PCR-inhibitory substances. The different performances of the filter devices

  4. AirData

    EPA Pesticide Factsheets

    The AirData site provides access to yearly summaries of United States air pollution data, taken from EPA's air pollution databases. AirData has information about where air pollution comes from (emissions) and how much pollution is in the air outside our homes and work places (monitoring).

  5. Improved methods for magnetic purification of malaria parasites and haemozoin

    PubMed Central

    2010-01-01

    Background Malaria parasites generate free haem upon catabolism of host haemoglobin during their intraerythrocytic growth cycle. In order to minimize oxidative toxicity of the ferric iron, the free haem molecules are polymerized into the biomineral beta-haematin (commonly referred to as haemozoin). Haemozoin crystals are paramagnetic, and this property can be exploited for the purification of late stage parasites as they contain larger haemozoin crystals than early stage parasites and uninfected cells. Commercially available magnets that were originally developed for the purpose of antibody-mediated cell purification are widely used for this purpose. As these methods are not necessarily optimized for parasite purification, the relationship between magnetic field strength and the quantity and quality of yield during parasite purification was explored. Methods Inexpensive rare-earth neodymium magnets with commercially available disposable columns were employed to explore the relationship between magnetic field strength and recovery of free haemozoin and infected erythrocytes (iRBCs). Results Yields of free haemozoin increased nearly linearly with increasing magnetic field strength to the strongest fields tested (8,500 Gauss). Stronger magnetic fields also improved the recovery of iRBCs with no detrimental effects on parasite viability. An in-house constructed magnetic stand, built for $75 in materials, produced superior results when compared with much more expensive commercial products. Conclusions Existing protocols for the magnetic purification of free haemozoin and iRBCs result in sub-optimal yields. Inexpensive high-strength neodymium magnets offer a better option, resulting in higher yields with no detrimental effects on parasite viability. PMID:20074366

  6. Air cell

    NASA Astrophysics Data System (ADS)

    Okamura, Okiyoshi; Wakasa, Masayuki; Tamanoi, Yoshihito

    1991-04-01

    The present invention relates to an air cell. This air cell provides a compact light-weight power source for model aircraft permitting them to fly for an extended period so that they may be used for such practical purposes as crop dusting, surveying, and photographing. The cell is comprised of a current collector so disposed between a magnesium, zinc, or aluminum alloy cathode and a petroleum graphite anode that it is in contact with the anode. The anode is formed by adding polytetrafluoroethylene dispersion liquid in a mixture of active carbon and graphite powder, pouring the mixture into a mold and heating it to form the anode. It is fabricated by a plurality of anode sections and is formed with at least one hole so that it can provide a cell which is compact in size and light in weight yet is capable of generating a high output. The anode, the cathode, and a separator are wetted by an electrolytic liquid. The electrolyte is continuously supplied through the life of the cell.

  7. 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

  8. A synthetic zero air standard

    NASA Astrophysics Data System (ADS)

    Pearce, Ruth

    2016-04-01

    A Synthetic Zero Air Standard R. E. Hill-Pearce, K. V. Resner, D. R. Worton, P. J. Brewer The National Physical Laboratory Teddington, Middlesex TW11 0LW UK We present work towards providing traceability for measurements of high impact greenhouse gases identified by the World Meteorological Organisation (WMO) as critical for global monitoring. Standards for these components are required with challengingly low uncertainties to improve the quality assurance and control processes used for the global networks to better assess climate trends. Currently the WMO compatibility goals require reference standards with uncertainties of < 100 nmolmol-1 for CO2 (northern hemisphere) and < 2 nmolmol-1 for CH4 and CO. High purity zero gas is required for both the balance gas in the preparation of reference standards and for baseline calibrations of instrumentation. Quantification of the amount fraction of the target components in the zero gas is a significant contributor to the uncertainty and is challenging due to limited availability of reference standard at the amount fraction of the measurand and limited analytical techniques with sufficient detection limits. A novel dilutor was used to blend NPL Primary Reference Gas Mixtures containing CO2, CH4 and CO at atmospheric amount fractions with a zero gas under test. Several mixtures were generated with nominal dilution ratios ranging from 2000:1 to 350:1. The baseline of two cavity ring down spectrometers was calibrated using the zero gas under test after purification by oxidative removal of CO and hydrocarbons to < 1 nmolmol-1 (SAES PS15-GC50) followed by the removal of CO2 and water vapour to < 100 pmolmol-1 (SAES MC190). Using the standard addition method.[1] we have quantified the amount fraction of CO, CO2, and CH4 in scrubbed whole air (Scott Marrin) and NPL synthetic zero air. This is the first synthetic zero air standard with a matrix of N2, O2 and Ar closely matching ambient composition with gravimetrically assigned

  9. Air and the origin of the experimental plant physiology.

    PubMed

    Pennazio, Sergio

    2005-01-01

    It is well known that oxygen and carbon dioxide are two chemicals which enter the plant metabolism as nutrients. The bases of this nowadays obvious statement were placed in the 18th century by means of the works of ingenious naturalists such as Robert Boyle, Stephen Hales, Joseph Priestley, Jam Ingenhousz, Lazzaro Spallanzani and Theodore De Saussure. Till the end of the 17th century, the atmospheric air was considered as an ineffable spirit, the function of which was of physical nature. Boyle was the first naturalist to admit the possibility that respiration were an exchange of vapours occurring in the blood. Stephen Hales realised that air could be fixed by plants under the influence of solar light. Priestley showed that plants could regenerate the bad air making it breathable. Ingenhousz demonstrated that the green parts of plants performed the complete purification of air only under the influence of the light. Spallanzani discovered that plants respire and guessed that the good air (oxygen) originated from the fixed air (carbon dioxide). Finally, Theodore De Saussure showed that plants were able to adsorb carbon dioxide and to release oxygen in a proportional air. All these discoveries benefited of the results coming from investigations of scholars of the so-called "pneumatic chemistry" (Boyle himself, George Ernst Stahl, Joseph Black, Priestley himself, and many more others. But among all the eminent scientists above mentioned stands out the genius of Antoine Laurent Lavoisier, who revolutionised the chemistry of the 18th century ferrying it towards the modern chemistry.

  10. Evaluation of strategies to control Fab light chain dimer during mammalian expression and purification: A universal one-step process for purification of correctly assembled Fab.

    PubMed

    Spooner, Jennifer; Keen, Jenny; Nayyar, Kalpana; Birkett, Neil; Bond, Nicholas; Bannister, David; Tigue, Natalie; Higazi, Daniel; Kemp, Benjamin; Vaughan, Tristan; Kippen, Alistair; Buchanan, Andrew

    2015-07-01

    Fabs are an important class of antibody fragment as both research reagents and therapeutic agents. There are a plethora of methods described for their recombinant expression and purification. However, these do not address the issue of excessive light chain production that forms light chain dimers nor do they describe a universal purification strategy. Light chain dimer impurities and the absence of a universal Fab purification strategy present persistent challenges for biotechnology applications using Fabs, particularly around the need for bespoke purification strategies. This study describes methods to address light chain dimer formation during Fab expression and identifies a novel CH 1 affinity resin as a simple and efficient one-step purification for correctly assembled Fab.

  11. Effective purification of ginsenosides from cultured wild ginseng roots,red ginseng, and white ginseng with macroporous resins.

    PubMed

    Li, Huayue; Lee, Jae-Hwa; Ha, Jong-Myung

    2008-11-01

    This study was aimed (i) to develop an effective method for the purification of ginsenosides for industrial use and (ii) to compare the distribution of ginsenosides in cultured wild ginseng roots (adventitious root culture of Panax ginseng) with those of red ginseng (steamed ginseng) and white ginseng (air-dried ginseng). The crude extracts of cultured wild ginseng roots, red ginseng, and white ginseng were obtained by using a 75% ethanol extraction combined with ultrasonication. This was followed sequentially by AB-8 macroporous adsorption chromatography, Amberlite IRA 900 Cl anion-exchange chromatography, and Amberlite XAD16 adsorption chromatography for further purification. The contents of total ginsenosides were increased from 4.1%, 12.1%, and 11.3% in the crude extracts of cultured wild ginseng roots, red ginseng, and white ginseng to 79.4%, 71.7%, and 72.5% in the final products, respectively. HPLC analysis demonstrated that ginsenosides in cultured wild ginseng roots were distributed in a different ratio compared with red ginseng and white ginseng.

  12. Metal-Air Batteries

    SciTech Connect

    Zhang, Jiguang; Bruce, Peter G.; Zhang, Gregory

    2011-08-01

    Metal-air batteries have much higher specific energies than most currently available primary and rechargeable batteries. Recent advances in electrode materials and electrolytes, as well as new designs on metal-air batteries, have attracted intensive effort in recent years, especially in the development of lithium-air batteries. The general principle in metal-air batteries will be reviewed in this chapter. The materials, preparation methods, and performances of metal-air batteries will be discussed. Two main metal-air batteries, Zn-air and Li-air batteries will be discussed in detail. Other type of metal-air batteries will also be described.

  13. Ammonia Adsorption of Four Thailand White Charcoals for Air Purification Application

    NASA Astrophysics Data System (ADS)

    Pijarn, Nuchanaporn; Sribuarai, Tinnphat; Butsee, Manipa; Buakul, Kanokwan; Seng, Hasan; Phonprasert, Pongtep; Kitisriworaphan, Thanate; Atthameth, Prasertsil

    2017-06-01

    The goal of this work was to study the efficiency of ammonia adsorption of four white charcoals include Bamboo, Coconut spathe, Coconut shell and Miscellaneous woods. The ammonia 20 mL was used as the odour sample for adsorption, 0.1 grams of each white charcoal was used as adsorbent and adsorption time were studied in 20, 40, 60, 80, and 100 min. The gravimetric method was used as method for study ammonia adsorption. The results show all white charcoals have saturated adsorption in range 40-60 min. The sequent of ammonia adsorption with white charcoal from descending were Miscellaneous > Coconut spathe > Coconut shell > Bamboo. A statistical test with Paired Samples T-Test, the result of four white charcoal to absorb the odour of ammonia in the all adsorption times have difference statistically significant at the 95% confidence.

  14. Porous TiO2 microspheres with tunable properties for photocatalytic air purification.

    PubMed

    Naldoni, Alberto; Bianchi, Claudia L; Pirola, Carlo; Suslick, Kenneth S

    2013-01-01

    The synthesis of highly-crystalline porous TiO(2) microspheres is reported using ultrasonic spray pyrolysis (USP) in the presence of colloidal silica as a template. We have exploited the interactions between hot SiO(2) template particles surface and TiO(2) precursor that occur during reaction inside the droplets, to control the physical and chemical properties of the resulting particles. Varying the SiO(2) to titanium precursor molar ratio and the colloidal silica dimension, we obtained porous titania microspheres with tunable morphology, porosity, BET surface area, crystallite size, band-gap, and phase composition. In this regard, we have also observed the preferential formation of anatase vs. rutile with increasing initial surface area of the silica template. The porous TiO(2) microspheres were tested in the photocatalytic degradation of nitrogen oxides (NO(x)) in the gas phase. USP prepared nanostructured titania samples were found to have significantly superior specific activity per surface area compared to a commercial reference sample (P25 by Evonik-Degussa). Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Nano-Scale Metal Oxide Particles as Materials for Air Purification

    DTIC Science & Technology

    1994-02-22

    carried out. Methods for preparing the nanoscale particles, including core/shell overlayer particles, have been worked out. Surface characterization...since these heteroatoms are notorious for catalyst poisoning. Solid reagents that might serve as effective destructive adsorbents must have high capacity...to basic and applied science. Further understanding of their Avadlab1i1ty Codem vRiI1 and/ar Dgst Specle. |~1 1 I] Pagr 3 synthesis , properties, and

  16. EVALUATION OF THE POLYAD FB AIR PURIFICATION AND SOLVENT RECOVERY PROCESS FOR STYRENE REMOVAL

    EPA Science Inventory

    The report gives results of a study evaluating the Polyad fluidized-bed (FB) process for controlling styrene emissions at a representative fiberglass shower stall and bath tub manufacturing plan*t. he process was evaluated using a transport able unit supplied by Weatherly, Inc., ...

  17. EVALUATION OF THE POLYAD FB AIR PURIFICATION AND SOLVENT RECOVERY PROCESS FOR STYRENE REMOVAL

    EPA Science Inventory

    The report gives results of a study evaluating the Polyad fluidized-bed (FB) process for controlling styrene emissions at a representative fiberglass shower stall and bath tub manufacturing plan*t. he process was evaluated using a transport able unit supplied by Weatherly, Inc., ...

  18. Tuned air gun array

    SciTech Connect

    Ruehle, W.H.

    1983-05-10

    The present invention provides a method for determining the spacing and size of air guns in a tuned air gun array. Volume ratios are calculated based upon a predetermined maximum volume for any individual air gun. The volumes are cross-referenced to spacings for optimum air gun interaction. The resulting air gun array operates as a broadband high-energy point source.

  19. AMBIENT AIR MONITORING STRATEGY

    EPA Science Inventory

    The Clean Air Act requires EPA to establish national ambient air quality standards and to regulate as necessary, hazardous air pollutants. EPA uses ambient air monitoring to determine current air quality conditions, and to assess progress toward meeting these standards and relat...

  20. The Blood Compatibilities of Blood Purification Membranes and Other Materials Developed in Japan

    PubMed Central

    Abe, Takaya; Kato, Karen; Fujioka, Tomoaki; Akizawa, Tadao

    2011-01-01

    The biocompatibilities in blood purification therapy are defined as “a concept to stipulate safety of blood purification therapy by an index based on interaction in the body arising from blood purification therapy itself.” The biocompatibilities are associated with not only materials to be used but also many factors such as sterilization method and eluted substance. It is often evaluated based on impacts on cellular pathways and on humoral pathways. Since the biocompatibilities of blood purification therapy in particular hemodialysis are not just a prognostic factor for dialysis patients but a contributory factor for long-term complications, it should be considered with adequate attention. It is important that blood purification therapy should be performed by consistently evaluating not only risks associated with these biocompatibilities but also the other advantages obtained from treatments. In this paper, the biocompatibilities of membrane and adsorption material based on Japanese original which are used for blood purification therapy are described. PMID:21969830

  1. Air and Water System (AWS) Design and Technology Selection for the Vision for Space Exploration

    NASA Technical Reports Server (NTRS)

    Jones, Harry; Kliss, Mark

    2005-01-01

    This paper considers technology selection for the crew air and water recycling systems to be used in long duration human space exploration. The specific objectives are to identify the most probable air and water technologies for the vision for space exploration and to identify the alternate technologies that might be developed. The approach is to conduct a preliminary first cut systems engineering analysis, beginning with the Air and Water System (AWS) requirements and the system mass balance, and then define the functional architecture, review the International Space Station (ISS) technologies, and discuss alternate technologies. The life support requirements for air and water are well known. The results of the mass flow and mass balance analysis help define the system architectural concept. The AWS includes five subsystems: Oxygen Supply, Condensate Purification, Urine Purification, Hygiene Water Purification, and Clothes Wash Purification. AWS technologies have been evaluated in the life support design for ISS node 3, and in earlier space station design studies, in proposals for the upgrade or evolution of the space station, and in studies of potential lunar or Mars missions. The leading candidate technologies for the vision for space exploration are those planned for Node 3 of the ISS. The ISS life support was designed to utilize Space Station Freedom (SSF) hardware to the maximum extent possible. The SSF final technology selection process, criteria, and results are discussed. Would it be cost-effective for the vision for space exploration to develop alternate technology? This paper will examine this and other questions associated with AWS design and technology selection.

  2. Air and Water System (AWS) Design and Technology Selection for the Vision for Space Exploration

    NASA Technical Reports Server (NTRS)

    Jones, Harry; Kliss, Mark

    2005-01-01

    This paper considers technology selection for the crew air and water recycling systems to be used in long duration human space exploration. The specific objectives are to identify the most probable air and water technologies for the vision for space exploration and to identify the alternate technologies that might be developed. The approach is to conduct a preliminary first cut systems engineering analysis, beginning with the Air and Water System (AWS) requirements and the system mass balance, and then define the functional architecture, review the International Space Station (ISS) technologies, and discuss alternate technologies. The life support requirements for air and water are well known. The results of the mass flow and mass balance analysis help define the system architectural concept. The AWS includes five subsystems: Oxygen Supply, Condensate Purification, Urine Purification, Hygiene Water Purification, and Clothes Wash Purification. AWS technologies have been evaluated in the life support design for ISS node 3, and in earlier space station design studies, in proposals for the upgrade or evolution of the space station, and in studies of potential lunar or Mars missions. The leading candidate technologies for the vision for space exploration are those planned for Node 3 of the ISS. The ISS life support was designed to utilize Space Station Freedom (SSF) hardware to the maximum extent possible. The SSF final technology selection process, criteria, and results are discussed. Would it be cost-effective for the vision for space exploration to develop alternate technology? This paper will examine this and other questions associated with AWS design and technology selection.

  3. Joint Doctrine and Joint Tactics, Techniques, and Procedures for Air Mobility Opearations

    DTIC Science & Technology

    2007-11-02

    135 boom type aircraft refueling an F-15E. I-13 General Overview receptacle. Boom refueling allows for the rapid transfer of fuel under high pressure ...had spread to epidemic levels from consumption of contaminated water. A C-5 loaded with a reverse osmosis water purification unit (ROWPU) would help...fixed-wing aircraft. Movement of patients requires special air traffic control considerations to comply with patient-driven altitude and pressurization

  4. Air supply valve for seismic air gun

    SciTech Connect

    Otto, B.

    1989-07-25

    This paper describes an improvement in a marine seismic array adapted to be towed by a vessel wherein the array is comprised of a plurality of air guns spaced along an array bundle which includes a central air hose assembly that supplies compressed air to each of the air guns through individual air passages which extend between the central air hose assembly and each of the air guns. The improvement comprising: an air supply valve positioned in each of the individual air passages, the air supply valve comprising: a housing having inlet and an outlet and a passage in the housing connecting the inlet and the outlet; valve means positioned in the passage in the housing; valve actuating means in the housing for moving the valve means from an open position to a closed position and from a closed position to an open position; means for remotely actuating the valve actuating means from the vessel to close the valve to deactivate the air gun and to reopen the valve to reactivate the air gun whereby each of the plurality of air guns can be individually inactivated and reactivated remotely from the vessel.

  5. Magnetically ultraresponsive nanoscavengers for next-generation water purification systems

    PubMed Central

    Zhang, Mingliang; Xie, Xing; Tang, Mary; Criddle, Craig S.; Cui, Yi; Wang, Shan X.

    2014-01-01

    The development of sustainable, robust and energy efficient water purification technology is still challenging. Although use of nanoparticles is promising, methods are needed for their efficient recovery post treatment. Here we address this issue by fabrication of magnetically ultraresponsive ‘nanoscavengers’, nanoparticles containing synthetic antiferromagnetic core layers and functional capping layers. When dispersed in water, the nanoscavengers efficiently interact with contaminants to remove them from the water. They are then quickly collected (<5 min) with a permanent magnet, owing to their magnetically ultraresponsive core layers. Specifically, we demonstrate fabrication and deployment of Ag-capped nanoscavengers for disinfection followed by application of an external magnetic field for separation. We also develop and validate a collision-based model for pathogen inactivation, and propose a cyclical water purification scheme in which nanoscavengers are recovered and recycled for contaminant removal. PMID:23673651

  6. Quantum amplification and purification of noisy coherent states

    NASA Astrophysics Data System (ADS)

    Zhao, Xiaobin; Chiribella, Giulio

    2017-04-01

    Quantum-limited amplifiers increase the amplitude of quantum signals at the price of introducing additional noise. Quantum purification protocols operate in the reverse way, by reducing the noise while attenuating the signal. Here we investigate a scenario that interpolates between these two extremes. We search for the optimal physical process that generates M approximate copies of a pure and amplified coherent state, starting from N copies of a noisy coherent state with Gaussian modulation. We prove that the optimal deterministic processes are always Gaussian, whereas non-Gaussianity powers up probabilistic advantages in suitable parameter regimes. The optimal processes are experimentally realizable with current technology, both in the deterministic and in the probabilistic scenario. In view of this fact, we provide benchmarks that can be used to certify the experimental demonstration of the quantum-enhanced amplification and purification of coherent states.

  7. Preparative Purification of Recombinant Proteins: Current Status and Future Trends

    PubMed Central

    Saraswat, Mayank; Ravidá, Alessandra; Holthofer, Harry

    2013-01-01

    Advances in fermentation technologies have resulted in the production of increased yields of proteins of economic, biopharmaceutical, and medicinal importance. Consequently, there is an absolute requirement for the development of rapid, cost-effective methodologies which facilitate the purification of such products in the absence of contaminants, such as superfluous proteins and endotoxins. Here, we provide a comprehensive overview of a selection of key purification methodologies currently being applied in both academic and industrial settings and discuss how innovative and effective protocols such as aqueous two-phase partitioning, membrane chromatography, and high-performance tangential flow filtration may be applied independently of or in conjunction with more traditional protocols for downstream processing applications. PMID:24455685

  8. Production and purification of the multifunctional enzyme horseradish peroxidase

    PubMed Central

    Spadiut, Oliver; Herwig, Christoph

    2014-01-01

    The oxidoreductase horseradish peroxidase (HRP) is used in numerous industrial and medical applications. In this review, we briefly describe this well-studied enzyme and focus on its promising use in targeted cancer treatment. In combination with a plant hormone, HRP can be used in specific enzyme–prodrug therapies. Despite this outstanding application, HRP has not found its way as a biopharmaceutical into targeted cancer therapy yet. The reasons therefore lie in the present low-yield production and cumbersome purification of this enzyme from its natural source. However, surface glycosylation renders the recombinant production of HRP difficult. Here, we compare different production hosts for HRP and summarize currently used production and purification strategies for this enzyme. We further present our own strategy of glycoengineering this powerful enzyme to allow recombinant high-yield production in Pichia pastoris and subsequent simple downstream processing. PMID:24683473

  9. Quantum resources for purification and cooling: fundamental limits and opportunities

    PubMed Central

    Ticozzi, Francesco; Viola, Lorenza

    2014-01-01

    Preparing a quantum system in a pure state is ultimately limited by the nature of the system's evolution in the presence of its environment and by the initial state of the environment itself. We show that, when the system and environment are initially uncorrelated and arbitrary joint unitary dynamics is allowed, the system may be purified up to a certain (possibly arbitrarily small) threshold if and only if its environment, either natural or engineered, contains a “virtual subsystem” which has the same dimension and is in a state with the desired purity. Beside providing a unified understanding of quantum purification dynamics in terms of a “generalized swap process,” our results shed light on the significance of a no-go theorem for exact ground-state cooling, as well as on the quantum resources needed for achieving an intended purification task. PMID:24898845

  10. Liquid xenon purification, de-radonation (and de-kryptonation)

    SciTech Connect

    Pocar, Andrea

    2015-08-17

    Liquid xenon detectors are at the forefront of rare event physics, including searches for neutrino-less double beta decay and WIMP dark matter. The xenon for these experiments needs to be purified from chemical impurities such as electronegative atoms and molecules, which absorb ionization electrons, and VUV (178 nm) scintillation light-absorbing chemical species. In addition, superb purification from radioactive impurities is required. Particularly challenging are radioactive noble isotopes ({sup 85}Kr,{sup 39,42}Ar,{sup 220,222}Rn). Radon is a particularly universal problem, due to the extended decay sequence of its daughters and its ubiquitous presence in detector materials. Purification and de-radonation of liquid xenon are addressed with particular focus on the experience gained with the EXO-200 neutrino-less double beta decay detector.

  11. Development of silicon purification by strong radiation catalysis method

    NASA Astrophysics Data System (ADS)

    Chen, Ying-Tian; Ho, Tso-Hsiu; Lim, Chern-Sing; Lim Boon, Han

    2010-11-01

    Using a new type of solar furnace and a specially designed induction furnace, cost effective and highly efficient purification of metallurgical silicon into solar grade silicon can be achieved. It is realized by a new method for extracting boron from silicon with the aid of photo-chemical effect. In this article, we discussed the postulated principle of strong radiation catalysis and the recent development in practice. Starting from ordinary metallurgical silicon, we achieved a purification result of 0.12 ppmw to 0.3 ppmw of boron impurity in silicon by only single pass of a low cost and simple process, the major obstacle to make ‘cheap’ solar grade silicon feedstock in industry is thus removed.

  12. An alternate high yielding purification method for Clitoria ternatea lectin.

    PubMed

    Naeem, Aabgeena; Ahmad, Ejaz; Khan, Rizwan Hasan

    2007-10-01

    In our previous publication we had reported the purification and characterization of Clitoria ternatea agglutinin from its seeds on fetuin CL agarose affinity column, designated CTA [A. Naeem, S. Haque, R.H. Khan. Protein J., 2007]. Since CTA binds beta-d-galactosides, this lectin can be used as valuable tool for glycobiology studies in biomedical and cancer research. So an attempt was made for a high yielding alternative purification method employing the use of asialofetuin CL agarose column for the above-mentioned lectin, designated CTL. The fetuin affinity purified agglutinin was found similar to asialofetuin affinity purified lectin in SDS pattern, HPLC and N-terminal sequence. The content of lectin was found to be 30mg/30g dry weight of pulse. The yield was 2.8% as compared to 0.3% obtained on fetuin column. The number of tryptophan and tyrosine estimated was four and six per subunit.

  13. Purification of the functional plant membrane channel KAT1

    SciTech Connect

    Hibi, Takao Aoki, Shiho; Oda, Keisuke; Munemasa, Shintaro; Ozaki, Shunsuke; Shirai, Osamu; Murata, Yoshiyuki; Uozumi, Nobuyuki

    2008-09-26

    The inward-rectifying K{sup +} channel KAT1 is expressed mainly in Arabidopsis thaliana guard cells. The purification of functional KAT1 has never been reported. We investigated the extraction of the plant K{sup +} channel KAT1 with different detergents, as an example for how to select detergents for purifying a eukaryotic membrane protein. A KAT1-GFP fusion protein was used to screen a library of 46 detergents for the effective solubilization of intact KAT1. Then, a 'test set' of three detergents was picked for further analysis, based on their biochemical characteristics and availability. The combination use of the selected detergents enabled the effective purification of functional KAT1 with affinity and gel-filtration chromatography.

  14. Fractionation-purification of an industrial kraft lignin

    SciTech Connect

    Lundquist, K.; Kirk, T.K.

    1980-01-01

    The potential of the by-product lignins from kraft pulping operations (kraft lignins) as renewable chemical resources has long been recognized. Research through several decades into the utilization of these modified lignins has resulted in a number of products, and, because of changes in the economics of petroleum-based chemicals, research is probably accelerating. Ready availability has caused kraft lignins also to be used widely as experimental lignins for studies of microbiological degradation and for other investigations. Unfortunately, kraft lignins have often been studied with little if any purification, even without freeing them of non-lignin-derived materials and low-molecular weight kraft degradation products of lignin. As a result, it is often difficult to interpret reported findings. The present paper describes the simple purification, by fractionation, of an industrial kraft lignin and some of the properties of the fractions.

  15. Expression, Solubilization, and Purification of Bacterial Membrane Proteins.

    PubMed

    Jeffery, Constance J

    2016-02-02

    Bacterial integral membrane proteins play many important roles, including sensing changes in the environment, transporting molecules into and out of the cell, and in the case of commensal or pathogenic bacteria, interacting with the host organism. Working with membrane proteins in the lab can be more challenging than working with soluble proteins because of difficulties in their recombinant expression and purification. This protocol describes a standard method to express, solubilize, and purify bacterial integral membrane proteins. The recombinant protein of interest with a 6His affinity tag is expressed in E. coli. After harvesting the cultures and isolating cellular membranes, mild detergents are used to solubilize the membrane proteins. Protein-detergent complexes are then purified using IMAC column chromatography. Support protocols are included to help select a detergent for protein solubilization and for use of gel filtration chromatography for further purification.

  16. [Purification and breaking techniques for cysts of Giardia spp].

    PubMed

    Polverino, D; Molina, N B; Minvielle, M C; Lozano, M E; Basualdo, J A

    2004-01-01

    The purpose of this study was to optimize and evaluate the purification techniques, isolation and breaking of cysts of Giardia spp from fecal samples to isolate DNA. Filtrated fecal samples were tested in 3 purification techniques: Telleman solution, sucrose and Telleman plus sucrose. The sucrose solution let us to isolate the cysts with less detritus. The cleaned cysts were splited in 3 techniques to test the breaking: osmotic shock and heat, chemistry degradation and thermic shock, enzymatic action and mechanic effect. Only the last method was successful and showed bands in agarose gel. The result of this study shows a routine and common method which could be used in the previous steps to the PCR technique for the genotypification of these parasites.

  17. Study on a new water purification equipment with spiral lamellas

    NASA Astrophysics Data System (ADS)

    Feng, X. R.

    2017-08-01

    A new water purification equipment was introduced, especially the section of spiral lamellas. Utilization of spiral lamellas made the sedimentation space reach to 100%, not only improving sedimentation efficiency and reducing the cover space, but also saving investment. Production test results showed that the new water purification equipment with spiral lamellas had characteristics of excellent treatment efficiency and high shock resistant capacity. As the treatment water volume was 240 m3/d, when the turbidity, CODMn and UV254 were 203 NTU, 1.90 mg/L and 0.030 cm-1 in raw water, they were 0.32 NTU, 0.72mg/L and 0.011 cm-1 respectively in effluent water, which could fully meet the drinking water hygiene requirement.

  18. A scintillator purification plant and fluid handling system for SNO+

    NASA Astrophysics Data System (ADS)

    Ford, Richard J.

    2015-08-01

    A large capacity purification plant and fluid handling system has been constructed for the SNO+ neutrino and double-beta decay experiment, located 6800 feet underground at SNOLAB, Canada. SNO+ is a refurbishment of the SNO detector to fill the acrylic vessel with liquid scintillator based on Linear Alkylbenzene (LAB) and 2 g/L PPO, and also has a phase to load natural tellurium into the scintillator for a double-beta decay experiment with 130Te. The plant includes processes multi-stage dual-stream distillation, column water extraction, steam stripping, and functionalized silica gel adsorption columns. The plant also includes systems for preparing the scintillator with PPO and metal-loading the scintillator for double-beta decay exposure. We review the basis of design, the purification principles, specifications for the plant, and the construction and installations. The construction and commissioning status is updated.

  19. Highly parallel oligonucleotide purification and functionalization using reversible chemistry.

    PubMed

    York, Kerri T; Smith, Ryan C; Yang, Rob; Melnyk, Peter C; Wiley, Melissa M; Turk, Casey M; Ronaghi, Mostafa; Gunderson, Kevin L; Steemers, Frank J

    2012-01-01

    We have developed a cost-effective, highly parallel method for purification and functionalization of 5'-labeled oligonucleotides. The approach is based on 5'-hexa-His phase tag purification, followed by exchange of the hexa-His tag for a functional group using reversible reaction chemistry. These methods are suitable for large-scale (micromole to millimole) production of oligonucleotides and are amenable to highly parallel processing of many oligonucleotides individually or in high complexity pools. Examples of the preparation of 5'-biotin, 95-mer, oligonucleotide pools of >40K complexity at micromole scale are shown. These pools are prepared in up to ~16% yield and 90-99% purity. Approaches for using this method in other applications are also discussed.

  20. Highly parallel oligonucleotide purification and functionalization using reversible chemistry

    PubMed Central

    York, Kerri T.; Smith, Ryan C.; Yang, Rob; Melnyk, Peter C.; Wiley, Melissa M.; Turk, Casey M.; Ronaghi, Mostafa; Gunderson, Kevin L.; Steemers, Frank J.

    2012-01-01

    We have developed a cost-effective, highly parallel method for purification and functionalization of 5′-labeled oligonucleotides. The approach is based on 5′-hexa-His phase tag purification, followed by exchange of the hexa-His tag for a functional group using reversible reaction chemistry. These methods are suitable for large-scale (micromole to millimole) production of oligonucleotides and are amenable to highly parallel processing of many oligonucleotides individually or in high complexity pools. Examples of the preparation of 5′-biotin, 95-mer, oligonucleotide pools of >40K complexity at micromole scale are shown. These pools are prepared in up to ~16% yield and 90–99% purity. Approaches for using this method in other applications are also discussed. PMID:22039155

  1. Treatment of hyperbilirubinemia with blood purification in China

    PubMed Central

    Duan, Zhi-Jun; Li, Lei-Lei; Ju, Jia; Gao, Zhi-Hong; He, Gao-Hong

    2006-01-01

    The incidence of hyperbilirubinemia is high clinically, which is difficult to cure by medication, surgery or interventional therapies. Non-bioartificial liver is the main alternative in the blood purification for hyperbilirubinemia, which includes plasma exchange, hemoperfusion, hemodialysis, molecular adsorbent recycling system and so on. The research results and clinical experiences in China show that these methods are effective in lowering high levels of bilirubin with fewer side effects. The hyperbilirubinemias of different causes, with different complications or accompanying different diseases can be treated by different methods. Bioartificial liver, hybrid artificial liver support system and adsorbent membrane material have also been studied and their development in reducing hyperbilirubinemias has been achieved. This article gives a brief overview on the actuality and research improvement in blood purification for hyperbilirubinemia in China. PMID:17167835

  2. Recent advances in microbial biopolymer production and purification.

    PubMed

    Kreyenschulte, Dirk; Krull, Rainer; Margaritis, Argyrios

    2014-03-01

    Over the past decades a large amount of biopolymers originating from various types of microorganisms have been reported. With ongoing research the number of possible applications has increased rapidly, ranging from use as food additives and biomedical agents to biodegradable plastics from renewable resources. In spite of the plethora of applications, the large-scale introduction of biopolymers into the market has often been forestalled by high production costs mainly due to complex or inefficient downstream processing. In this article, state-of-the-art methods and recent advances in the separation and purification of microbial polymers are reviewed, with special focus on the biopolymers, γ-polyglutamic acid and xanthan gum. Furthermore, a study of the general factors affecting production and purification is presented, including biopolymer rheology, enzymatic degradation and production of biopolymer mixtures.

  3. A scintillator purification plant and fluid handling system for SNO+

    SciTech Connect

    Ford, Richard J.

    2015-08-17

    A large capacity purification plant and fluid handling system has been constructed for the SNO+ neutrino and double-beta decay experiment, located 6800 feet underground at SNOLAB, Canada. SNO+ is a refurbishment of the SNO detector to fill the acrylic vessel with liquid scintillator based on Linear Alkylbenzene (LAB) and 2 g/L PPO, and also has a phase to load natural tellurium into the scintillator for a double-beta decay experiment with {sup 130}Te. The plant includes processes multi-stage dual-stream distillation, column water extraction, steam stripping, and functionalized silica gel adsorption columns. The plant also includes systems for preparing the scintillator with PPO and metal-loading the scintillator for double-beta decay exposure. We review the basis of design, the purification principles, specifications for the plant, and the construction and installations. The construction and commissioning status is updated.

  4. Large-scale purification and crystallization of adenovirus hexon.

    PubMed

    Rux, John J; Burnett, Roger M

    2007-01-01

    This chapter provides a protocol for the large-scale purification of adenovirus type 2 and 5 virions and the soluble major coat protein hexon. The purified virus particles remain intact and are suitable for vector, vaccine, or structural studies and can also be used as seed stock for further rounds of infection. The hexon may be used to produce crystals suitable for high-resolution X-ray crystallographic studies. Briefly, virus is propagated in HeLa cell suspension cultures. The infected cells are lysed, virions and hexon are separated by centrifugation, and the protein is then further purified by anion exchange chromatography. The entire purification procedure takes approx 1 wk and typically yields 10(13) virus particles and 10-20 mg of highly purified hexon.

  5. Exhaust gas purification system for lean burn engine

    DOEpatents

    Haines, Leland Milburn

    2002-02-19

    An exhaust gas purification system for a lean burn engine includes a thermal mass unit and a NO.sub.x conversion catalyst unit downstream of the thermal mass unit. The NO.sub.x conversion catalyst unit includes at least one catalyst section. Each catalyst section includes a catalytic layer for converting NO.sub.x coupled to a heat exchanger. The heat exchanger portion of the catalyst section acts to maintain the catalytic layer substantially at a desired temperature and cools the exhaust gas flowing from the catalytic layer into the next catalytic section in the series. In a further aspect of the invention, the exhaust gas purification system includes a dual length exhaust pipe upstream of the NO.sub.x conversion catalyst unit. The dual length exhaust pipe includes a second heat exchanger which functions to maintain the temperature of the exhaust gas flowing into the thermal mass downstream near a desired average temperature.

  6. Purification of microsomal signal peptidase as a complex.

    PubMed Central

    Evans, E A; Gilmore, R; Blobel, G

    1986-01-01

    We report here the purification to near homogeneity of signal peptidase from canine pancreatic microsomes. Purification was monitored using an improved post-translational assay. A 42-fold enrichment over starting membranes was achieved by selective solubilization in nonionic detergent/high-salt buffer followed by gradient sievorptive anion and cation exchange chromatography, hydroxylapatite chromatography, gel filtration, and sucrose gradient velocity sedimentation. When examined by NaDodSO4/PAGE, the purified enzyme consisted of a complex of six polypeptides with apparent molecular masses of 25, 23, 22, 21, 18, and 12 kDa. The 22- and 23-kDa subunits were shown to be glycoproteins based on their sensitivity to endoglycosidase H and their ability to bind concanavalin A. We suggest that only one subunit of this complex carries out signal peptide cleavage. The structural association of the other subunits in stoichiometric amounts may reflect their requirement in chain translocation across the microsomal membrane. Images PMID:3511473

  7. Magnetically ultraresponsive nanoscavengers for next-generation water purification systems.

    PubMed

    Zhang, Mingliang; Xie, Xing; Tang, Mary; Criddle, Craig S; Cui, Yi; Wang, Shan X

    2013-01-01

    The development of sustainable, robust and energy efficient water purification technology is still challenging. Although use of nanoparticles is promising, methods are needed for their efficient recovery post treatment. Here we address this issue by fabrication of magnetically ultraresponsive 'nanoscavengers', nanoparticles containing synthetic antiferromagnetic core layers and functional capping layers. When dispersed in water, the nanoscavengers efficiently interact with contaminants to remove them from the water. They are then quickly collected (<5 min) with a permanent magnet, owing to their magnetically ultraresponsive core layers. Specifically, we demonstrate fabrication and deployment of Ag-capped nanoscavengers for disinfection followed by application of an external magnetic field for separation. We also develop and validate a collision-based model for pathogen inactivation, and propose a cyclical water purification scheme in which nanoscavengers are recovered and recycled for contaminant removal.

  8. Recent Methods for Purification and Structure Determination of Oligonucleotides

    PubMed Central

    Zhang, Qiulong; Lv, Huanhuan; Wang, Lili; Chen, Man; Li, Fangfei; Liang, Chao; Yu, Yuanyuan; Jiang, Feng; Lu, Aiping; Zhang, Ge

    2016-01-01

    Aptamers are single-stranded DNA or RNA oligonucleotides that can interact with target molecules through specific three-dimensional structures. The excellent features, such as high specificity and affinity for target proteins, small size, chemical stability, low immunogenicity, facile chemical synthesis, versatility in structural design and engineering, and accessible for site-specific modifications with functional moieties, make aptamers attractive molecules in the fields of clinical diagnostics and biopharmaceutical therapeutics. However, difficulties in purification and structural identification of aptamers remain a major impediment to their broad clinical application. In this mini-review, we present the recently attractive developments regarding the purification and identification of aptamers. We also discuss the advantages, limitations, and prospects for the major methods applied in purifying and identifying aptamers, which could facilitate the application of aptamers. PMID:27999357

  9. Highly efficient and easy protease-mediated protein purification.

    PubMed

    Last, Daniel; Müller, Janett; Dawood, Ayad W H; Moldenhauer, Eva J; Pavlidis, Ioannis V; Bornscheuer, Uwe T

    2016-02-01

    As both research on and application of proteins are rarely focused on the resistance towards nonspecific proteases, this property remained widely unnoticed, in particular in terms of protein purification and related fields. In the present study, diverse aspects of protease-mediated protein purification (PMPP) were explored on the basis of the complementary proteases trypsin and proteinase K as well as the model proteins green fluorescent protein (GFP) from Aequorea victoria, lipase A from Candida antarctica (CAL-A), a transaminase from Aspergillus fumigatus (AspFum), quorum quenching lactonase AiiA from Bacillus sp., and an alanine dehydrogenase from Thermus thermophilus (AlaDH). While GFP and AiiA were already known to be protease resistant, the thermostable enzymes CAL-A, AspFum, and AlaDH were selected due to the documented correlation between thermostability and protease resistance. As proof of principle for PMPP, recombinant GFP remained unaffected whereas most Escherichia coli (E. coli) host proteins were degraded by trypsin. PMPP was highly advantageous compared to the widely used heat-mediated purification of commercial CAL-A. The resistance of AspFum towards trypsin was improved by rational protein design introducing point mutation R20Q. Trypsin also served as economical and efficient substitute for site-specific endopeptidases for the removal of a His-tag fused to AiiA. Moreover, proteolysis of host enzymes with interfering properties led to a strongly improved sensitivity and accuracy of the NADH assay in E. coli cell lysate for AlaDH activity measurements. Thus, PMPP is an attractive alternative to common protein purification methods and facilitates also enzyme characterization in cell lysate.

  10. Reverse osmosis membrane of high urea rejection properties. [water purification

    NASA Technical Reports Server (NTRS)

    Johnson, C. C.; Wydeven, T. J. (Inventor)

    1980-01-01

    Polymeric membranes suitable for use in reverse osmosis water purification because of their high urea and salt rejection properties are prepared by generating a plasma of an unsaturated hydrocarbon monomer and nitrogen gas from an electrical source. A polymeric membrane is formed by depositing a polymer of the unsaturated monomer from the plasma onto a substrate, so that nitrogen from the nitrogen gas is incorporated within the polymer in a chemically combined form.

  11. Partial purification of protective antigens from Nippostrongylus brasiliensis in mice.

    PubMed

    Rhalem, A; Bourdieu, C; Luffau, G; Pery, P

    1988-01-01

    The purification of antigens from Nippostrongylus brasiliensis, through their ability to provoke cellular proliferation of immune cells and through their recognition by antibodies, led to an antigenic preparation which was extracted from adult worms and which contained only two proteins (MW 14 and 43 Kd). Mice which were vaccinated by the oral route after the entrapment of these two proteins in liposomes were strongly protected.

  12. Purification of Sewage Contaminated by Oil Products Using Mesoporous Coal

    NASA Astrophysics Data System (ADS)

    Gvazava, Elene; Maisuradze, Nino; Samkharadze, Irma

    2016-10-01

    The sorption properties of mesoporous coals (pore size of ∼⃒ 4 nm, the specific surface area of 25 to 150 m2/g) of Georgian hard coal deposit have been studied and the efficacy of their usage for the treatment of sewage water polluted by oil products has been established. Purification rate depends on coal mass loaded in filter, grain size, initial concentration of oil products, the water acidity, etc.

  13. Dynamical entanglement purification using chains of atoms and optical cavities

    SciTech Connect

    Gonta, Denis; Loock, Peter van

    2011-10-15

    In the framework of cavity QED, we propose a practical scheme to purify dynamically a bipartite entangled state using short chains of atoms coupled to high-finesse optical cavities. In contrast to conventional entanglement purification protocols, we avoid controlled-not gates, thus reducing complicated pulse sequences and superfluous qubit operations. Our interaction scheme works in a deterministic way and, together with entanglement distribution and swapping, opens a route toward efficient quantum repeaters for long-distance quantum communication.

  14. Purification of spent chromium bath by membrane electrolysis.

    PubMed

    Korzenowski, C; Rodrigues, M A S; Bresciani, L; Bernardes, A M; Ferreira, J Z

    2008-04-15

    The present study deals with the purification of spent chromium bath contaminated by trivalent chromium, iron and aluminum. The ionic transfer of Fe(III) depends on the presence of chloride ions on the pH while aluminum transfer is not affected by chromium(III) chloride. Five different commercial cation-exchange membranes were used. Nafion and PC-SK membranes showed the best results for trivalent iron and aluminum transfer.

  15. Aqueous Chloride Operations Overview: Plutonium and Americium Purification/Recovery

    SciTech Connect

    Gardner, Kyle Shelton; Kimball, David Bryan; Skidmore, Bradley Evan

    2016-09-28

    These are a set of slides intended for an information session as part of recruiting activities at Brigham Young University. It gives an overview of aqueous chloride operations, specifically on plutonium and americium purification/recovery. This presentation details the steps taken perform these processes, from plutonium size reduction, dissolution, solvent extraction, oxalate precipitation, to calcination. For americium recovery, it details the CLEAR (chloride extraction and actinide recovery) Line, oxalate precipitation and calcination.

  16. Tests of alternative reductants in the second uranium purification cycle

    SciTech Connect

    Thompson, M.C.

    1980-05-01

    Miniature mixer-settler tests of the second uranium purification cycle show that plutonium cannot be removed by hydroxylamine-hydrazine (NH/sub 2/OH-N/sub 2/H/sub 4/) because the acidity is too high, or by 2,5-di-t-pentylhydroquinone because HNO/sub 3/ oxidizes the hydroquinone. Plutonium can be removed satisfactorily when U(IV)-hydrazine is used as the reductant.

  17. Two-Step Vapor/Liquid/Solid Purification

    NASA Technical Reports Server (NTRS)

    Holland, L. R.

    1986-01-01

    Vertical distillation system combines in single operation advantages of multiple zone refining with those of distillation. Developed specifically to load Bridgman-Stockbarger (vertical-solidification) growth ampoules with ultrapure tellurium and cadmium, system, with suitable modifications, serves as material refiner. In first phase of purification process, ampoule heated to drive off absorbed volatiles. Second phase, evaporator heated to drive off volatiles in charge. Third phase, slowly descending heater causes distillation from evaporator to growing crystal in ampoule.

  18. Ecological aspects of the extreme purification of water

    NASA Astrophysics Data System (ADS)

    Shaposhnik, Vladimir A.; Mazo, A. A.; Frölich, P.

    1991-11-01

    The influence on the eco-system of the products of the large-scale technology for the preparation of ultra-pure water required for the electronic and radiotechnical industries is examined. The distillation, ion-exchange, and membrane methods are subjected to a comparative analysis. It is shown that the membrane method for the extreme purification of water is ecologically the most desirable. The methods for the elimination of nitrates from drinking water are examined. The bibliography includes 41 references.

  19. Superhydrophobic coated apparatus for liquid purification by evaporative condensation

    DOEpatents

    Simpson, John T; McNeany, Steve R; Dinsmore, Thomas V; Hunter, Scott R; Ivanov, Ilia N

    2014-03-11

    Disclosed are examples of apparatuses for evaporative purification of a contaminated liquid. In each example, there is a first vessel for storing the contaminated fluid. The first vessel includes a surface coated with a layer of superhydrophobic material and the surface is at least partially in contact with the contaminated liquid. The contaminants do not adhere to the surface as the purified liquid evaporates, thus simplifying maintenance of the apparatus.

  20. Simple method for purification of enterotoxigenic E. coli fimbriae

    PubMed Central

    Curtis, Brittany; Grassel, Christen; Laufer, Rachel; Sears, Khandra; Pasetti, Marcela F.; Barry, Eileen M.; Simon, Raphael

    2016-01-01

    Enterotoxigenic E. coli (ETEC) are endemic pathogens in the developing world. They frequently cause illness in travelers, and are among the most prevalent causes of diarrheal disease in children. Pathogenic ETEC strains employ fimbriae as adhesion factors to bind the luminal surface of the intestinal epithelium and establish infection. Accordingly, there is marked interest in immunoprophylactic strategies targeting fimbriae to protect against ETEC infections. Multiple strategies have been reported for purification of ETEC fimbriae, however none is ideal. Purification has typically involved the use of highly virulent wild-type strains. We report here a simple and improved method to purify ETEC fimbriae, which was applied to obtain two different Class 5 fimbriae types of clinical relevance (CFA/I and CS4) expressed recombinantly in E. coli production strains. Following removal from cells by shearing, fimbriae proteins were purified by orthogonal purification steps employing ultracentrifugation, precipitation, and ion-exchange membrane chromatography. Purified fimbriae demonstrated the anticipated size and morphology by electron microscopy analysis, contained negligible levels of residual host cell proteins, nucleic acid, and endotoxin, and were recognized by convalescent human anti-sera. PMID:26581778

  1. Purification and Characterization of Bovine Serum Albumin Using Chromatographic Method

    PubMed Central

    Balkani, Sanaz; Shamekhi, Sara; Raoufinia, Ramin; Parvan, Reza; Abdolalizadeh, Jalal

    2016-01-01

    Purpose: Albumin is an abundant protein of blood and has many biopharmaceutical applications. The aim of this study was to purify bovine serum albumin (BSA) using produced rabbit anti-BSA antibody. Methods: The polyclonal antibody was produced against the BSA in rabbits. Then, the pure BSA was injected to three white New Zealand rabbits. ELISA test was done to evaluate antibody production. After antibody purification,the purified antibody was attached to CNBr-activated sepharose and finally it was used for purification of albumin from bovine serum. Western blotting analysis was used for functional assessment of immunoaffinity purified BSA. Results: The titer of anti-bovine albumin determined by ELISA was obtained 1: 256000. The SDS-PAGE showed up to 98% purity of isolated BSA and western blotting confirmed the BSA functionality. Purified bovine serum albumin by affinity chromatography showed a single band with molecular weight of 66 KDa. Conclusion: Affinity chromatography using produced rabbit anti-BSA antibody would be an economical and safe method for purification of BSA. PMID:28101473

  2. Simplified purification method for Clostridium difficile toxin A

    PubMed Central

    Fu, Si-Wu; Xue, Jing; Zhang, Ya-Li; Zhou, Dian-Yuan

    2004-01-01

    AIM: To establish the purification method for Clostridium difficile (C. difficile) toxin A. METHODS: C. difficile VPI 10463 filtrate was cultured anaerobically by the dialysis bag methods. And then the toxin A was purified by precipitation with 500 g/L (NH4)2SO4 and acid precipitation at pH5.5, followed by ion-exchange chromatography on DEAE-Toyopearl. RESULTS: Purified toxin A exhibited only one band on native polyacrylamide gel electrophoresis (native-PAGE) and Ouchterlony double immunodiffusion. The molecular weight of toxin A was estimated to be 550000. The purified toxin A had a protein concentration of 0.881 mg/mL. The minimum lethal dose was 1 × 106 MLD/mL (i.p.mice). The cytotoxic titer was 107 CU/mg. The haemagglutinate activity was at a concentration of 1.72 μg/mL. The ratio of fluid volume (mL) accumulated to the length (cm) of the loop was 2.46. CONCLUSION: The modified method for purification of toxin A of C. difficile was simple and convenient. It may be even more suitable for purification of toxin A on large scales. PMID:15309736

  3. Simplified purification method for Clostridium difficile toxin A.

    PubMed

    Fu, Si-Wu; Xue, Jing; Zhang, Ya-Li; Zhou, Dian-Yuan

    2004-09-15

    To establish the purification method for Clostridium difficile (C. difficile) toxin A. C. difficile VPI 10463 filtrate was cultured anaerobically by the dialysis bag methods. And then the toxin A was purified by precipitation with 500 g/L (NH4)2SO4 and acid precipitation at pH 5.5, followed by ion-exchange chromatography on DEAE-Toyopearl. Purified toxin A exhibited only one band on native polyacrylamide gel electrophoresis (native-PAGE) and Ouchterlony double immunodiffusion. The molecular weight of toxin A was estimated to be 550,000. The purified toxin A had a protein concentration of 0.881 mg/mL. The minimum lethal dose was 1X10(6) MLD/mL (i.p.mice). The cytotoxic titer was 10(7) CU/mg. The haemagglutinate activity was at a concentration of 1.72 microg/mL. The ratio of fluid volume (mL) accumulated to the length (cm) of the loop was 2.46. The modified method for purification of toxin A of C. difficile was simple and convenient. It may be even more suitable for purification of toxin A on large scales.

  4. Protein purification and crystallization artifacts: The tale usually not told.

    PubMed

    Niedzialkowska, Ewa; Gasiorowska, Olga; Handing, Katarzyna B; Majorek, Karolina A; Porebski, Przemyslaw J; Shabalin, Ivan G; Zasadzinska, Ewelina; Cymborowski, Marcin; Minor, Wladek

    2016-03-01

    The misidentification of a protein sample, or contamination of a sample with the wrong protein, may be a potential reason for the non-reproducibility of experiments. This problem may occur in the process of heterologous overexpression and purification of recombinant proteins, as well as purification of proteins from natural sources. If the contaminated or misidentified sample is used for crystallization, in many cases the problem may not be detected until structures are determined. In the case of functional studies, the problem may not be detected for years. Here several procedures that can be successfully used for the identification of crystallized protein contaminants, including: (i) a lattice parameter search against known structures, (ii) sequence or fold identification from partially built models, and (iii) molecular replacement with common contaminants as search templates have been presented. A list of common contaminant structures to be used as alternative search models was provided. These methods were used to identify four cases of purification and crystallization artifacts. This report provides troubleshooting pointers for researchers facing difficulties in phasing or model building.

  5. Matching relations for optimal entanglement concentration and purification

    PubMed Central

    Kong, Fan-Zhen; Xia, Hui-Zhi; Yang, Ming; Yang, Qing; Cao, Zhuo-Liang

    2016-01-01

    The bilateral controlled NOT (CNOT) operation plays a key role in standard entanglement purification process, but the CNOT operation may not be the optimal joint operation in the sense that the output entanglement is maximized. In this paper, the CNOT operations in both the Schmidt-projection based entanglement concentration and the entanglement purification schemes are replaced with a general joint unitary operation, and the optimal matching relations between the entangling power of the joint unitary operation and the non-maximal entangled channel are found for optimizing the entanglement in- crement or the output entanglement. The result is somewhat counter-intuitive for entanglement concentration. The output entanglement is maximized when the entangling power of the joint unitary operation and the quantum channel satisfy certain relation. There exist a variety of joint operations with non-maximal entangling power that can induce a maximal output entanglement, which will greatly broaden the set of the potential joint operations in entanglement concentration. In addition, the entanglement increment in purification process is maximized only by the joint unitary operations (including CNOT) with maximal entangling power. PMID:27189800

  6. Chitinase III in Euphorbia characias latex: Purification and characterization.

    PubMed

    Spanò, Delia; Pospiskova, Kristyna; Safarik, Ivo; Pisano, Maria Barbara; Pintus, Francesca; Floris, Giovanni; Medda, Rosaria

    2015-12-01

    This paper deals with the purification of a class III endochitinase from Euphorbia characias latex. Described purification method includes an effective novel separation step using magnetic chitin particles. Application of magnetic affinity adsorbent noticeably simplifies and shortens the purification procedure. This step and the subsequently DEAE-cellulose chromatography enable to obtain the chitinase in homogeneous form. One protein band is present on PAGE in non-denaturing conditions and SDS-PAGE profile reveals a unique protein band of 36.5 ± 2 kDa. The optimal chitinase activity is observed at 50 °C, pH 5.0. E. characias latex chitinase is able to hydrolyze colloidal chitin giving, as reaction products, N-acetyl-D-glucosamine, chitobiose and chitotriose. Moreover, we observed that calcium and magnesium ions enhance chitinase activity. Finally, we cloned the cDNA encoding the E. characias latex chitinase. The partial cDNA nucleotide sequence contains 762 bp, and the deduced amino acid sequence (254 amino acids) is homologous to the sequence of several plant class III endochitinases. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Novel High-throughput Approach for Purification of Infectious Virions

    PubMed Central

    James, Kevin T.; Cooney, Brad; Agopsowicz, Kate; Trevors, Mary Ann; Mohamed, Adil; Stoltz, Don; Hitt, Mary; Shmulevitz, Maya

    2016-01-01

    Viruses are extensively studied as pathogens and exploited as molecular tools and therapeutic agents. Existing methods to purify viruses such as gradient ultracentrifugation or chromatography have limitations, for example demand for technical expertise or specialized equipment, high time consumption, and restricted capacity. Our laboratory explores mutations in oncolytic reovirus that could improve oncolytic activity, and makes routine use of numerous virus variants, genome reassortants, and reverse engineered mutants. Our research pace was limited by the lack of high-throughput virus purification methods that efficiently remove confounding cellular contaminants such as cytokines and proteases. To overcome this shortcoming, we evaluated a commercially available resin (Capto Core 700) that captures molecules smaller than 700 kDa. Capto. Core 700 chromatography produced virion purity and infectivity indistinguishable from CsCl density gradient ultracentrifugation as determined by electron microscopy, gel electrophoresis analysis and plaque titration. Capto Core 700 resin was then effectively adapted to a rapid in-slurry pull-out approach for high-throughput purification of reovirus and adenovirus. The in-slurry purification approach offered substantially increased virus purity over crude cell lysates, media, or high-spin preparations and would be especially useful for high-throughput virus screening applications where density gradient ultracentrifugation is not feasible. PMID:27827454

  8. Expression, purification, and characterization of formaldehyde dehydrogenase from Pseudomonas aeruginosa.

    PubMed

    Zhang, Wangluo; Chen, Shuai; Liao, Yuanping; Wang, Dingli; Ding, Jianfeng; Wang, Yingming; Ran, Xiaoyuan; Lu, Daru; Zhu, Huaxing

    2013-12-01

    As a member of zinc-containing medium-chain alcohol dehydrogenase family, formaldehyde dehydrogenase (FDH) can oxidize toxic formaldehyde to less active formate with NAD(+) as a cofactor and exists in both prokaryotes and eukaryotes. Most FDHs are well known to be glutathione-dependent in the catalysis of formaldehyde oxidation, but the enzyme from Pseudomonas putida is an exception, which is independent of glutathione. To identify novel glutathione-independent FDHs from other bacterial strains and facilitate the corresponding structural and enzymatic studies, high-level soluble expression and efficient purification of these enzymes need to be achieved. Here, we present molecular cloning, expression, and purification of the FDH from Pseudomonas aeruginosa, which is a Gram-negative pathogenic bacterium causing opportunistic human infection. The FDH of P. aeruginosa shows high sequence identity (87.97%) with that of P. putida. Our results indicated that coexpression with molecular chaperones GroES, GroEL, and Tig has significantly attenuated inclusion body formation and improved the solubility of the recombinant FDH in Escherichiacoli cells. A purification protocol including three chromatographic steps was also established to isolate the recombinant FDH to homogeneity with a yield of ∼3.2 mg from 1L of cell culture. The recombinant P. aeruginosa FDH was properly folded and biologically functional, as demonstrated by the mass spectrometric, crystallographic, and enzymatic characterizations of the purified proteins. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Single-Step Purification of Cyclotides Using Affinity Chromatography.

    PubMed

    Uddin, Shaikh Jamal; Muhammad, Taj; Shafiullah, Md; Slazak, Blazej; Rouf, Razina; Göransson, Ulf

    2016-12-23

    Cyclotides are considered promising scaffolds for drug development owing to their inherent host defence activities and highly stable structure, defined by the cyclic cystine knot. These proteins are expressed as complex mixtures in plants. Although several methods have been developed for their isolation and analysis, purification of cyclotides is still a lengthy process. Here, we describe the use of affinity chromatography for the purification of cyclotides using polyclonal IgG antibodies raised in rabbits against cycloviolacin O2 and immobilized on NHS-activated Sepharose columns. Cycloviolacin O2 was used as a model substance to evaluate the chromatographic principle, first as a pure compound and then in combination with other cyclotides, i.e. bracelet cyclotide cycloviolacin O19 and Möbius cyclotide kalata B1, and in a plant extract. We demonstrate that single-step purification of cyclotides by affinity chromatography is possible but cross reactivity may occur between homologue cyclotides of the bracelet subfamily. This article is protected by copyright. All rights reserved.

  10. Design and function of biomimetic multilayer water purification membranes

    PubMed Central

    Ling, Shengjie; Qin, Zhao; Huang, Wenwen; Cao, Sufeng; Kaplan, David L.; Buehler, Markus J.

    2017-01-01

    Multilayer architectures in water purification membranes enable increased water throughput, high filter efficiency, and high molecular loading capacity. However, the preparation of membranes with well-organized multilayer structures, starting from the nanoscale to maximize filtration efficiency, remains a challenge. We report a complete strategy to fully realize a novel biomaterial-based multilayer nanoporous membrane via the integration of computational simulation and experimental fabrication. Our comparative computational simulations, based on coarse-grained models of protein nanofibrils and mineral plates, reveal that the multilayer structure can only form with weak interactions between nanofibrils and mineral plates. We demonstrate experimentally that silk nanofibril (SNF) and hydroxyapatite (HAP) can be used to fabricate highly ordered multilayer membranes with nanoporous features by combining protein self-assembly and in situ biomineralization. The production is optimized to be a simple and highly repeatable process that does not require sophisticated equipment and is suitable for scaled production of low-cost water purification membranes. These membranes not only show ultrafast water penetration but also exhibit broad utility and high efficiency of removal and even reuse (in some cases) of contaminants, including heavy metal ions, dyes, proteins, and other nanoparticles in water. Our biomimetic design and synthesis of these functional SNF/HAP materials have established a paradigm that could lead to the large-scale, low-cost production of multilayer materials with broad spectrum and efficiency for water purification, with applications in wastewater treatment, biomedicine, food industry, and the life sciences. PMID:28435877

  11. New membranes for extracorporeal blood purification in septic conditions.

    PubMed

    Bello, G; Di Muzio, F; Maviglia, R; Antonelli, M

    2012-11-01

    Severe sepsis and septic shock are still the leading cause of mortality and morbidity in the intensive care unit. The inflammatory response to infection is associated with an impressive, systemic release of pro- and anti-inflammatory mediators, which results in generalized endothelial damage, multiple organ failure and altered cellular immunological responsiveness. Over the last years, the substantial advances in the understanding of sepsis have led to the development of a large number of new approaches and technologies in the management of septic patients. Extracorporeal blood purification techniques using various membrane materials have been proposed to modulate multiple inflammatory mediators, and seem to be a potential adjuvant in the treatment of sepsis. However, the use of extracorporeal blood purification techniques during sepsis still remains controversial, thus precluding any definitive recommendations on the benefit of these methods. More data are needed to better recognize septic patients who are most likely to benefit from blood purification treatments, and clarify the optimal timing, duration, and number of applications of these techniques in the daily clinical practice.

  12. Recent advances in production, purification and applications of phycobiliproteins.

    PubMed

    Sonani, Ravi Raghav; Rastogi, Rajesh Prasad; Patel, Rutvij; Madamwar, Datta

    2016-02-26

    An obligatory sunlight requirement for photosynthesis has exposed cyanobacteria to different quantity and quality of light. Cyanobacteria can exhibit efficient photosynthesis over broad region (450 to 650 nm) of solar spectrum with the help of brilliantly coloured pigment proteins called phycobiliproteins (PBPs). Besides light-harvesting, PBPs are found to involve in several life sustaining phenomena including photoprotection in cyanobacteria. The unique spectral features (like strong absorbance and fluorescence), proteineous nature and, some imperative properties like hepato-protective, anti-oxidants, anti-inflammatory and anti-aging activity of PBPs enable their use in food, cosmetics, pharmaceutical and biomedical industries. PBPs have been also noted to show beneficial effect in therapeutics of some disease like Alzheimer and cancer. Such large range of applications increases the demand of PBPs in commodity market. Therefore, the large-scale and coast effective production of PBPs is the real need of time. To fulfil this need, many researchers have been working to find the potential producer of PBPs for the production and purification of PBPs. Results of these efforts have caused the inventions of some novel techniques like mixotrophic and heterotrophic strategies for production and aqueous two phase separation for purification purpose. Overall, the present review summarises the recent findings and identifies gaps in the field of production, purification and applications of this biological and economically important proteins.

  13. Purification of Lamins and Soluble Fragments of NETs.

    PubMed

    Makarov, Alexandr A; Rizzotto, Andrea; Meinke, Peter; Schirmer, Eric C

    2016-01-01

    Lamins and associated nuclear envelope transmembrane proteins (NETs) present unique problems for biochemical studies. Lamins form insoluble intermediate filament networks, associate with chromatin, and are also connected via specific NETs to the cytoskeleton, thus further complicating their isolation and purification from mammalian cells. Adding to this complexity, NETs at the inner nuclear membrane function in three distinct environments: (a) their nucleoplasmic domain(s) can bind lamins, chromatin, and transcriptional regulators; (b) they possess one or more integral transmembrane domains; and (c) their lumenal domain(s) function in the unique reducing environment of the nuclear envelope/ER lumen. This chapter describes strategic considerations and protocols to facilitate biochemical studies of lamins and NET proteins in vitro. Studying these proteins in vitro typically involves first expressing specific polypeptide fragments in bacteria and optimizing conditions to purify each fragment. We describe parameters for choosing specific fragments and designing purification strategies and provide detailed purification protocols. Biochemical studies can provide fundamental knowledge including binding strengths and the molecular consequences of disease-causing mutations that will be essential to understand nuclear envelope-genome interactions and nuclear envelope linked disease mechanisms. © 2016 Elsevier Inc. All rights reserved.

  14. Advective hydrogel membrane chromatography for monoclonal antibody purification in bioprocessing.

    PubMed

    Hou, Ying; Brower, Mark; Pollard, David; Kanani, Dharmesh; Jacquemart, Renaud; Kachuik, Bradley; Stout, James

    2015-01-01

    Protein A chromatography is widely employed for the capture and purification of monoclonal antibodies (mAbs). Because of the high cost of protein A resins, there is a significant economic driving force to seek new downstream processing strategies. Membrane chromatography has emerged as a promising alternative to conventional resin based column chromatography. However, to date, the application has been limited to mostly ion exchange flow through (FT) mode. Recently, significant advances in Natrix hydrogel membrane has resulted in increased dynamic binding capacities for proteins, which makes membrane chromatography much more attractive for bind/elute operations. The dominantly advective mass transport property of the hydrogel membrane has also enabled Natrix membrane to be run at faster volumetric flow rates with high dynamic binding capacities. In this work, the potential of using Natrix weak cation exchange membrane as a mAb capture step is assessed. A series of cycle studies was also performed in the pilot scale device (> 30 cycles) with good reproducibility in terms of yield and product purities, suggesting potential for improved manufacturing flexibility and productivity. In addition, anion exchange (AEX) hydrogel membranes were also evaluated with multiple mAb programs in FT mode. Significantly higher binding capacity for impurities (support mAb loads up to 10Kg/L) and 40X faster processing speed were observed compared with traditional AEX column chromatography. A proposed protein A free mAb purification process platform could meet the demand of a downstream purification process with high purity, yield, and throughput.

  15. Doping reversed-phase media for improved peptide purification.

    PubMed

    Khalaf, Rushd; Forrer, Nicola; Buffolino, Gianluca; Gétaz, David; Bernardi, Susanna; Butté, Alessandro; Morbidelli, Massimo

    2015-06-05

    The purification of therapeutic peptides is most often performed using one or more reversed phase chromatography steps. This ensures high purities while keeping the costs of purification under control. In this paper, a doped reversed phase chromatographic material is tested and compared to traditional reversed phase materials. The doping consists of adding limited amounts of ion exchange ligands to the surface of the material to achieve orthogonal separation and increase the non-hydrophobic interactions with the surface. These ionic groups can either be attractive (opposite charge), or repulsive (same charge) to the peptide. The benefit of this new doped reversed phase material is shown through increases in selectivity in diluted conditions and yield and productivity in overloaded (i.e. industrial) conditions. It is the conjectured that all performance characteristics should increase using repulsive doping groups, whereas these characteristics should decrease when using attractive doping groups. This conjecture is shown to be true through several examples, including purifications of industrially relevant peptide crudes, in industrially relevant conditions. Moreover, the effect of ionic strength and organic modifier concentration was explored and shown to be in line with the expected behavior.

  16. Purification of baculovirus vectors using heparin affinity chromatography

    PubMed Central

    Nasimuzzaman, Md; Lynn, Danielle; van der Loo, Johannes CM; Malik, Punam

    2016-01-01

    Baculoviruses are commonly used for recombinant protein and vaccine production. Baculoviruses are nonpathogenic to vertebrates, have a large packaging capacity, display broad host and cell type tropism, infect both dividing and nondividing cells, and do not elicit strong immune or allergic responses in vivo. Hence, their use as gene delivery vehicles has become increasingly popular in recent years. Moreover, baculovirus vectors carrying mammalian regulatory elements can efficiently transduce and express transgenes in mammalian cells. Based on the finding that heparan sulfate, which is structurally similar to heparin, is an attachment receptor for baculovirus, we developed a novel scalable baculovirus purification method using heparin-affinity chromatography. Baculovirus supernatants were loaded onto a POROS heparin column, washed to remove unbound materials, and eluted with 1.5 mol/l NaCl, which yielded a recovery of purified baculovirus of 85%. After ultracentrifugation, baculovirus titers increased from 200- to 700-fold with overall yields of 26–29%. We further show that baculovirus particles were infectious, normal in morphology and size, despite high-salt elution and shear forces used during purification and concentration. Our chromatography-based purification method is scalable and, together with ultracentrifugation and/or tangential flow filtration, will be suitable for large-scale manufacturing of baculovirus stocks for protein and vaccine production and in gene therapy applications. PMID:27933303

  17. Purification and Characterization of Bovine Serum Albumin Using Chromatographic Method.

    PubMed

    Balkani, Sanaz; Shamekhi, Sara; Raoufinia, Ramin; Parvan, Reza; Abdolalizadeh, Jalal

    2016-12-01

    Purpose: Albumin is an abundant protein of blood and has many biopharmaceutical applications. The aim of this study was to purify bovine serum albumin (BSA) using produced rabbit anti-BSA antibody. Methods: The polyclonal antibody was produced against the BSA in rabbits. Then, the pure BSA was injected to three white New Zealand rabbits. ELISA test was done to evaluate antibody production. After antibody purification,the purified antibody was attached to CNBr-activated sepharose and finally it was used for purification of albumin from bovine serum. Western blotting analysis was used for functional assessment of immunoaffinity purified BSA. Results: The titer of anti-bovine albumin determined by ELISA was obtained 1: 256000. The SDS-PAGE showed up to 98% purity of isolated BSA and western blotting confirmed the BSA functionality. Purified bovine serum albumin by affinity chromatography showed a single band with molecular weight of 66 KDa. Conclusion: Affinity chromatography using produced rabbit anti-BSA antibody would be an economical and safe method for purification of BSA.

  18. Purification of a Multidrug Resistance Transporter for Crystallization Studies

    PubMed Central

    Alegre, Kamela O.; Law, Christopher J.

    2015-01-01

    Crystallization of integral membrane proteins is a challenging field and much effort has been invested in optimizing the overexpression and purification steps needed to obtain milligram amounts of pure, stable, monodisperse protein sample for crystallography studies. Our current work involves the structural and functional characterization of the Escherichia coli multidrug resistance transporter MdtM, a member of the major facilitator superfamily (MFS). Here we present a protocol for isolation of MdtM to increase yields of recombinant protein to the milligram quantities necessary for pursuit of structural studies using X-ray crystallography. Purification of MdtM was enhanced by introduction of an elongated His-tag, followed by identification and subsequent removal of chaperonin contamination. For crystallization trials of MdtM, detergent screening using size exclusion chromatography determined that decylmaltoside (DM) was the shortest-chain detergent that maintained the protein in a stable, monodispersed state. Crystallization trials of MdtM performed using the hanging-drop diffusion method with commercially available crystallization screens yielded 3D protein crystals under several different conditions. We contend that the purification protocol described here may be employed for production of high-quality protein of other multidrug efflux members of the MFS, a ubiquitous, physiologically and clinically important class of membrane transporters. PMID:27025617

  19. Preparative Purification of Liriodendrin from Sargentodoxa cuneata by Macroporous Resin

    PubMed Central

    Li, Di-Hua; Wang, Yan; Lv, Yuan-Shan; Liu, Jun-Hong; Yang, Lei; Zhang, Shu-Kun; Zhuo, Yu-Zhen

    2015-01-01

    The preparative purification of liriodendrin from Sargentodoxa cuneata using macroporous resin combined with crystallization process was evaluated. The properties of adsorption/desorption of liriodendrin on eight macroporous resins were investigated systematically. X-5 resin was selected as the most suitable medium for liriodendrin purification. The adsorption of liriodendrin on X-5 resin fitted well with the pseudo-second-order kinetic model and Langmuir isotherm model. Dynamic adsorption/desorption tests were performed using a glass column packed with X-5 resin to optimize the separation process of liriodendrin. After one treatment with X-5 resin, the content of liriodendrin in the product was increased 48.73-fold, from 0.85% to 41.42%, with a recovery yield of 88.9%. 97.48% liriodendrin was obtained by further crystallization and determined by HPLC. The purified product possessed strong antioxidant activity. In conclusion, purification of liriodendrin might expend its further pharmacological researches and further applications in pharmacy. PMID:26236742

  20. Purification for the XENONnT dark matter experiment

    NASA Astrophysics Data System (ADS)

    Brown, Ethan; Xenon Collaboration

    2017-01-01

    The XENON1T experiment uses 3.5 tons of liquid xenon in a cryogenic detector to search for dark matter. Its upgrade, XENONnT, will similarly house 7.5 tons of liquid xenon. Operation of these large detectors requires continual purification of the xenon in an external purifier, and the need for less than part per billion level oxygen in the xenon, coupled with the large quantity of xenon to be purified, places high demands on the rate of flow through this purification system. Building on the success of the XENON10 and XENON100 experiments, XENON1T circulates gaseous xenon through heated getters at a rate of up to 100 SLPM, pushing commercial pumps to their limits moving this large quantity of gas without interruption for several years. Two upgrades are considered for XENONnT. A custom high-capacity magnetic piston pump based on the one developed for the EXO200 experiment has been scaled up to support the high demands of this much larger experiment. Additionally, a liquid phase circulation and purification system that purifies the cryogenic liquid directly is being developed, which takes advantage of the much smaller volumetric flow demands of liquid relative to gas. The implementation of both upgrades will be presented. Supported by the National Science Foundation.