Sample records for air purification

  1. Air/Water Purification (United States)


    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. Nanostructured Catalytic Reactors for Air Purification Project (United States)

    National Aeronautics and Space Administration — This SBIR Phase I project proposes the development of lightweight compact nanostructured catalytic reactors for air purification from toxic gaseous organic...

  3. Nanostructured Catalytic Reactors for Air Purification Project (United States)

    National Aeronautics and Space Administration — This SBIR Phase II project proposes the development of lightweight compact nanostructured catalytic reactors for air purification from toxic gaseous organic...

  4. Solid State Air Purification System Project (United States)

    National Aeronautics and Space Administration — The purpose of this proposed research is to develop a new air purification system based on a liquid membrane, capable of purifying carbon dioxide from air in a far...

  5. The viability of photocatalysis for air purification. (United States)

    Hay, Stephen O; Obee, Timothy; Luo, Zhu; Jiang, Ting; Meng, Yongtao; He, Junkai; Murphy, Steven C; Suib, Steven


    Photocatalytic oxidation (PCO) air purification technology is reviewed based on the decades of research conducted by the United Technologies Research Center (UTRC) and their external colleagues. UTRC conducted basic research on the reaction rates of various volatile organic compounds (VOCs). The knowledge gained allowed validation of 1D and 3D prototype reactor models that guided further purifier development. Colleagues worldwide validated purifier prototypes in simulated realistic indoor environments. Prototype products were deployed in office environments both in the United States and France. As a result of these validation studies, it was discovered that both catalyst lifetime and byproduct formation are barriers to implementing this technology. Research is ongoing at the University of Connecticut that is applicable to extending catalyst lifetime, increasing catalyst efficiency and extending activation wavelength from the ultraviolet to the visible wavelengths. It is critical that catalyst lifetime is extended to realize cost effective implementation of PCO air purification.

  6. The Viability of Photocatalysis for Air Purification

    Directory of Open Access Journals (Sweden)

    Stephen O. Hay


    Full Text Available Photocatalytic oxidation (PCO air purification technology is reviewed based on the decades of research conducted by the United Technologies Research Center (UTRC and their external colleagues. UTRC conducted basic research on the reaction rates of various volatile organic compounds (VOCs. The knowledge gained allowed validation of 1D and 3D prototype reactor models that guided further purifier development. Colleagues worldwide validated purifier prototypes in simulated realistic indoor environments. Prototype products were deployed in office environments both in the United States and France. As a result of these validation studies, it was discovered that both catalyst lifetime and byproduct formation are barriers to implementing this technology. Research is ongoing at the University of Connecticut that is applicable to extending catalyst lifetime, increasing catalyst efficiency and extending activation wavelength from the ultraviolet to the visible wavelengths. It is critical that catalyst lifetime is extended to realize cost effective implementation of PCO air purification.

  7. Research of indoor smoke warning and air purification equipment

    Institute of Scientific and Technical Information of China (English)

    Wangronglong; Zhaoyexing; Fuyunhua


    In order to reduce indoor smoke concentration and improve indoor air quality,we put forward the intelligent indoor smoke warning and air purification device. This device can quickly reduce the concentration of indoor smoke by the air purification and fire alarm function. It provides a suitable living environment for people.

  8. Catalysis in air purification. Katalyse in der Abluftreinigung

    Energy Technology Data Exchange (ETDEWEB)

    Fink, K.; Joisten, M.; Neufert, R.; Sprehe, J.; Zuerbig, J. (Siemens AG, Redwitz (Germany). Bereich Energieerzeugung, Keramik- und Porzellanwerk Redwitz); Gajewski, W. (Siemens AG, Erlangen (Germany). Bereich Energieerzeugung, Zentrale Forschung und Entwicklung)


    In most cases katalytic purification of waste gas allows the reliable reduction of industrial emission to meet existing regulations. This method can remove numerous organic and inorganic compounds from waste air. This review deals with design, applications and function of such air purification units with special regard to the catalysts used. Furthermore, aspects of chemical engineering relevant for planning and construction are also discussed. (orig.).

  9. Breathing Air Purification for Hyperbaric Purposes, Part II

    Directory of Open Access Journals (Sweden)

    Woźniak Arkadiusz


    Full Text Available Determining the efficiency of breathing air purification for hyperbaric purposes with the use of filtration systems is of a crucial importance. However, when the Polish Navy took samples of breathing air from their own filtration plant for quality purposes, these were found to not meet the required standard. The identification of this problem imposed the need to undertake actions aimed at the elimination of the identified disruptions in the process of breathing air production, with the objective of assuring its proper quality. This study presents the results of the initial tests on the air supply sources utilised by the Polish Navy, which were carried out for the purpose of setting a proper direction of future works and implementing corrective measures in order to optimise the breathing air production process. The obtained test results will be used in a subsequent publication devoted to the assessment of the level of efficiency of air purification with the use of a multifaceted approach consisting in the utilisation of various types of air supply sources and different configurations of purification systems.

  10. NASA - Johnson Space Center's New Capabilities for Air Purification (United States)

    Graf, John


    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.

  11. Photodetoxification and purification of water and air

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, M. [Univ. of Wisconsin, Madison, WI (United States); Blake, D.M. [National Renewable Energy Lab., Golden, CO (United States)


    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.


    Directory of Open Access Journals (Sweden)

    V. V. Shitov


    Full Text Available Problem statement. Intensive wear of the structure bearing elements in premises with high moisture content in ventilated air is associated with cyclic changes in temperature and humidity indicators of steam-air environment; hence, the problem of ventilated air treatment in such premises is topical.Results. The design of device for integrated purification of atmospheric ventilated air from fine-dispersed pollutants in premise with high moisture content in indoor air is developed.Conclusions. The proposed device provides reliable and long-term operation of bearing building elements.

  13. Influence of Water Salinity on Air Purification from Hydrogen Sulfide

    Directory of Open Access Journals (Sweden)

    Leybovych L.I.


    Full Text Available Mathematical modeling of «sliding» water drop motion in the air flow was performed in software package FlowVision. The result of mathematical modeling of water motion in a droplet with diameter 100 microns at the «sliding» velocity of 15 m/s is shown. It is established that hydrogen sulfide oxidation occurs at the surface of phases contact. The schematic diagram of the experimental setup for studying air purification from hydrogen sulfide is shown. The results of the experimental research of hydrogen sulfide oxidation by tap and distilled water are presented. The dependence determining the share of hydrogen sulfide oxidized at the surface of phases contact from the dimensionless initial concentration of hydrogen sulfide in the air has been obtained.

  14. New research on bioregenerative air/water purification systems (United States)

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


    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.

  15. Air purification in a reverse-flow reactor: Model simulations vs. experiments

    NARCIS (Netherlands)

    Beld, van de L.; Westerterp, K.R.


    The behavior of a reverse-flow reactor was studied for the purification of polluted air by catalytic combustion. A heterogeneous one-dimensional model was extended with a heat balance for the reactor wall. An overall heat transport term is included to account for the small heat losses in radial dire

  16. Experimental research on photocatalytic oxidation air purification technology applied to aircraft cabins

    DEFF Research Database (Denmark)

    Sun, Yuexia; Fang, Lei; Wyon, David Peter


    The experiment presented in this report was performed in a simulated aircraft cabin to evaluate the air cleaning effects of two air purification devices that used photocatalytic oxidation (PCO) technology. Objective physical, chemical and physiological measurements and subjective human assessment...... of using PCO units on subjective assessments were observed after the first 3 1/4 hours of exposure. After 6 h of exposure, a positive effect of using either PCO unit on symptoms of dizziness and claustrophobia was observed....

  17. Experimental research on photocatalytic oxidation air purification technology applied to aircraft cabins

    DEFF Research Database (Denmark)

    Sun, Yuexia; Fang, Lei; Wyon, David P.


    The experiment presented in this report was performed in a simulated aircraft cabin to evalu-ate the air cleaning effects of two air purification devices using Photocatalytic Oxidation (PCO) technology. Objective physical, chemical and physiological measurements and subjec-tive human assessments ...... observed after the first 3¼ hours of exposure. After 6 hours of expo-sure, a positive effect of using either PCO units on symptoms of dizziness and claustrophobia were observed....

  18. Carbon Nanotube Electron Sources for Air Purification Project (United States)

    National Aeronautics and Space Administration — The innovation proposed here focuses on cleansing air with high energy electrons. Bombardment by electrons has proven to be effective in removing a wide spectrum of...

  19. Air purification in a reverse-flow reactor: Model simulations vs. experiments


    Beld, van de, L.; Westerterp, K.R.


    The behavior of a reverse-flow reactor was studied for the purification of polluted air by catalytic combustion. A heterogeneous one-dimensional model was extended with a heat balance for the reactor wall. An overall heat transport term is included to account for the small heat losses in radial direction. The calculations are compared to experimental data without using fit parameters. The agreement between simulations and experiments is generally good. Discrepancies can be explained mainly by...

  20. RHELP (Regenerative High Efficiency Low Pressure) Air Purification System (United States)


    4 (3), 269. 10. Allen, M. D. and Raabe, O. G., "Re-evaluation of millikan’s oil drop data for the motion of small particles in air," Journal of...rigorous physical filtration testing for collection efficiency, pressure drop , most penetrating particle size, and microwave sensitivity, among other...increased quality factor. More importantly, the synthesized filters were found to exceed military standards for HEPA filter with lower pressure drop . This

  1. Experimental study of photocatalytic concrete products for air purification

    Energy Technology Data Exchange (ETDEWEB)

    Huesken, G.; Hunger, M.; Brouwers, H.J.H. [Department of Civil Engineering, Faculty of Engineering Technology, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands)


    Air quality in inner-city areas is a topic which receives much attention nowadays but in the coming years, the overall interest on this topic will become even bigger. One major concern is caused by the reduction of the limiting values given by the European Council Directive 1999/30/EC [Relating to limit values for sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter and lead in ambient air. Official Journal of the European Communities 1999, L 163/41-60] and increasing traffic rates especially for diesel powered passenger cars and freight vehicles. A promising approach for solving the problem of nitrogen oxides (NO{sub x}) is the photochemical conversion of nitrogen oxides to low concentrated nitrates due to heterogeneous photocatalytic oxidation (PCO) using titanium dioxide (TiO{sub 2}) as photocatalyst. A variety of products containing TiO{sub 2} are already available on the European market and their working mechanism under laboratory conditions is proven. However, there is still a lack of transforming the experimental results obtained under laboratory conditions to practical applications considering real world conditions. This paper presents the research conducted on photocatalytic concrete products with respect to the evaluation of air-purifying properties. The degradation process of nitric oxide (NO) under laboratory conditions is studied using a test setup for measuring the performance of photocatalytic active concrete products. The test setup uses the UV-A induced degradation of NO and is oriented on the ISO standard ISO 22197-1:2007. Besides the introduction of the test setup, a uniform measuring procedure is presented to the reader which allows for an evaluation and direct comparison of the performance of photocatalytic active concrete products. This kind of direct comparison was not possible so far. Furthermore, the results of a comparative study on varying photocatalytic concrete products of the European market will be discussed

  2. Recent Photocatalytic Applications for Air Purification in Belgium

    Directory of Open Access Journals (Sweden)

    Elia Boonen


    Full Text Available Photocatalytic concrete constitutes a promising technique to reduce a number of air contaminants such as NOx and VOC’s, especially at sites with a high level of pollution: highly trafficked canyon streets, road tunnels, the urban environment, etc. Ideally, the photocatalyst, titanium dioxide, is introduced in the top layer of the concrete pavement for best results. In addition, the combination of TiO2 with cement-based products offers some synergistic advantages, as the reaction products can be adsorbed at the surface and subsequently be washed away by rain. A first application has been studied by the Belgian Road Research Center (BRRC on the side roads of a main entrance axis in Antwerp with the installation of 10.000 m² of photocatalytic concrete paving blocks. For now however, the translation of laboratory testing towards results in situ remains critical of demonstrating the effectiveness in large scale applications. Moreover, the durability of the air cleaning characteristic with time remains challenging for application in concrete roads. From this perspective, several new trial applications have been initiated in Belgium in recent years to assess the “real life” behavior, including a field site set up in the Leopold II tunnel of Brussels and the construction of new photocatalytic pavements on industrial zones in the cities of Wijnegem and Lier (province of Antwerp. This paper first gives a short overview of the photocatalytic principle applied in concrete, to continue with some main results of the laboratory research recognizing the important parameters that come into play. In addition, some of the methods and results, obtained for the existing application in Antwerp (2005 and during the implementation of the new realizations in Wijnegem and Lier (2010–2012 and in Brussels (2011–2013, will be presented.

  3. An Investigation on the Efficiency of Air Purification Using a Biofilter with Activated Bed of Different Origin

    Directory of Open Access Journals (Sweden)

    Zagorskis Alvydas


    Full Text Available Recent studies in the area of biological air treatment in filters have addressed fundamental key issues, such as a biofilter bed of different origin composed of natural zeolite granules, foam cubes and wood chips. When foam and zeolite are mixed with wood chips to remove volatile organic compounds from the air, not only biological but also adsorption air purification methods are accomplished. The use of complex purification technologies helps to improve the efficiency of a filter as well as the bed service life of the filter bed. Investigations revealed that microorganisms prevailing in biological purification, can also reproduce themselves in biofilter beds of inorganic and synthetic origin composed of natural zeolite and foam. By cultivating associations of spontaneous microorganisms in the filter bed the dependencies of the purification efficiency of filter on the origin, concentration and filtration time of injected pollutants were determined. The highest purification efficiency was obtained when air polluted with acetone vapour was supplied to the equipment at 0.1 m/s of superficial gas velocity. When cleaning air from volatile organic compounds (acetone, toluene and butanol, under the initial pollutant concentration of ~100 mg/m3, the filter efficiency reached 95 %.

  4. Physico-chemical Modification of the Fibrous Filter Nozzles for Purification Processes of Water and Air (United States)

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


    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.

  5. Soil-based filtration technology for air purification: potentials for environmental and space life support application (United States)

    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.

  6. Air Stripping Designs and Reactive Water Purification Processes for the Lunar Surface (United States)

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


    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.

  7. Slip-Effect Functional Air Filter for Efficient Purification of PM2.5 (United States)

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


    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.

  8. Purification/deodorization of indoor air and gaseous effluents by TiO{sub 2} photocatalysis

    Energy Technology Data Exchange (ETDEWEB)

    Pichat, P.; Disdier, J.; Hoang-Van, C.; Mas, D.; Goutailler, G.; Gaysse, C. [Laboratoire ' Photocatalyse, Catalyse et Environnement' , CNRS UMR ' IFoS' , Ecole Centrale de Lyon, BP 163, 69131 Ecully Cedex (France)


    Our objective was to further assess the capabilities of TiO{sub 2} to purify/deodorize indoor air and industrial gaseous effluents. Using a laboratory photoreactor including a lamp emitting around 365nm and a TiO{sub 2}-coated fiber glass mesh, we first determined that the removal rate of three very different pollutants (CO, n-octane, pyridine) was 5-10{mu}mol per Wh consumed by the lamp for 50-2000ppmv concentrations and 25-50lh{sup -1} flow rates (dry air or O{sub 2}). We inferred that this order of magnitude allows, by use of a reasonable-size apparatus, the abatement of pollutants in constantly renewed indoor air, except CO and CH{sub 4} that are too concentrated. Using a TiO{sub 2} photocatalysis-based individual air purifier prototype, we showed, through distinctive analytical measurements, that the average concentrations of benzene, toluene and xylenes were indeed reduced by a factor of 2-3 in an ordinary non-airtight room. We also showed that O{sub 3} addition in O{sub 2} very markedly increases the mineralization percentage of n-octane, under otherwise identical conditions, in the laboratory photoreactor without photoexcitation of O{sub 3}; this property of O{sub 3} can expand the application field of photocatalytic air purification in industry, at least in some cases.

  9. A Simple Introduction of Indoor Air Purification%浅谈净化室内空气的方法

    Institute of Scientific and Technical Information of China (English)



    Indoor environment pollution has become a under-recognized influence to everybody’ s health nowa-days;This article introduces the harm of Indoor air pollutants to human being, the advantages and disadvantages of several method of indoor air purifications, Finally several suggestions were given in choosing air purification equip-ment according to different kinds of indoor air pollutants.%目前室内环境污染已成为影响人们健康的“隐形”杀手。本文介绍了室内空气污染物对人体的危害,对多种空气净化技术的优缺点进行了阐述,并对室内不同的污染物选择与之相应的空气净化设备给出了建议。

  10. Indoor air purification of accommodations: the Japan experience; Epuration de l'air interieur des logements: l'experience du Japon

    Energy Technology Data Exchange (ETDEWEB)



    In Japan, domestic air cleaners are currently used in residential buildings since the 1980's. Particulates collection and deodorization techniques are more and more performing in order to fulfill a growing up market. This short paper presents the two main categories of purification techniques: mechanical and electrostatic. The principle of deodorization methods is presented too (adsorption, neutralization, oxidation, plasma). (J.S.)

  11. Techniques and Products for Air Purification%室内空气净化技术及产品综述

    Institute of Scientific and Technical Information of China (English)

    石芳芳; 邱利民; 于川; 张林; 宋佳; 严仁远


    Principles and characteristics of the indoor air purification techniques are introduced in this paper. The main challenges of cur-rent techniques are outlined. The combination principles of the air purification techniques are proposed by summarizing and analyzing the techniques applied in sorts of air purifiershe combination principles are: choosing the purification methods mainly based on the types of pollutants indoor and exploiting the synergistic effect between indoor air purification techniques to get the optimal and comprehensive puri-fication. his paper points out that studies on integrated purification technology exploiting synergistic effect purification techniques will be one of the most important researches in future.%如何在加快治理大气环境的同时,营造洁净健康的室内空气环境,是当前乃至今后相当长的一段时期国内外相关领域的持续热点。本文系统介绍了目前室内空气净化主要技术的原理及特点,指出现有技术存在的主要问题。通过对当前主流室内空气净化产品中应用的净化技术进行梳理,总结了空气净化技术的组合原则,即主要根据室内污染物类型进行针对性地选择,并利用净化技术间的协同效应,以使室内空气得到全面净化。本文还对未来的研发方向进行了展望,指出利用净化技术间的协同效应,研究更为有效的综合净化技术将成为未来重要的研究方向之一。

  12. TiO2-Impregnated Porous Silica Tube and Its Application for Compact Air- and Water-Purification Units

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Ochiai


    Full Text Available A simple, convenient, reusable, and inexpensive air- and water-purification unit including a one-end sealed porous amorphous-silica (a-silica tube coated with TiO2 photocatalyst layers has been developed. The porous a-silica layers were formed through outside vapor deposition (OVD. TiO2 photocatalyst layers were formed through impregnation and calcination onto a-silica layers. The resulting porous TiO2-impregnated a-silica tubes were evaluated for air-purification capacity using an acetaldehyde gas decomposition test. The tube (8.5 mm e.d. × 150 mm demonstrated a 93% removal rate for high concentrations (ca. 300 ppm of acetaldehyde gas at a single-pass condition with a 250 mL/min flow rate under UV irradiation. The tube also demonstrated a water purification capacity at a rate 2.0 times higher than a-silica tube without TiO2 impregnation. Therefore, the tubes have a great potential for developing compact and in-line VOC removal and water-purification units.

  13. Effects of indoor air purification by an air cleaning system (Koala technology) on semen parameters in male factor infertility: results of a pilot study. (United States)

    Paradisi, R; Vanella, S; Barzanti, R; Cani, C; Battaglia, C; Seracchioli, R; Venturoli, S


    A number of studies indicated a clear decline in semen quality in the past 30-50 years and there is accumulating evidence that this decline might result from exposure to high levels of air pollution. To examine the impact of environment on male reproductive ability, we undertook for the first time a pilot study on semen quality of infertile men exposed to purification of indoor air. Ten subjects with a history of unexplained male infertility and poor semen quality were exposed for at least 1 year to a cleaning indoor air system (Koala technology). The key feature of this air purifier is the unique innovative multiple filtering system. The treatment of total purification of indoor air showed neither improvements in semen parameters nor variation in reproductive hormones (P = N.S.), but induced an evident increase (P indoor air does not seem enough to improve semen quality, although the increase in leucocytic concentrations could indicate an activation of the role of immunosurveillance in a purified indoor air environment.

  14. Patent Information Analysis on Air Purification%空气净化技术专利情报分析

    Institute of Scientific and Technical Information of China (English)

    田军; 王晓鹏


    In this article, the basic trend of patent about air purification was analysed by year amount of patent application, areal distribu-tion and patent assignee using Thomoson Innovation. The analysis showed that application quantity of patent about air purification in-creased rapidly from 1999, and the main applicant countries were America, Japan and China. The primary patent assignees were Panason-ic, LG electronics and Donaldson. Technical constitution of air purification was analysed through International Patent Classification (IPC). The research found that major technologies in air purification were the filter and electrostatic separation of particulate matter, disin-fection and sterilization of air, and air-conditioning system. The key technology of main patent assignee was also analysed by patent the-mescape. Panasonic and LG focused on indoor air purification, but Donaldson involved industry air purification. The patent themescape al-so showed that patent layout of many research institutions and companies had related to almost all of the technology of air purification, but Chinese research institutions and companies had little patents.%利用专利情报分析工具Thomoson Innovation,分别通过每年专利申请量、区域分布、专利权人分析了空气净化领域的国际专利基本态势。通过分析得知,空气净化领域的专利申请量从1999年开始出现了迅速的增加,主要分布于美国、日本和中国,主要的专利权人为日本松下(Panasonic)、韩国乐金(LG)、美国唐纳森(Donaldson)公司。通过IPC分类分析了空气净化领域的技术构成,研究发现,空气净化涉及的主要技术领域包括颗粒物的过滤和静电分离、空气的消毒杀菌和空气的调节系统等。同时通过专利主题地形图分析了主要专利权人的技术特点,日本松下和韩国乐金主要集中于室内空气的净化,而美国唐纳森(Donaldson)的技术布局主要涉及工业空气净化。通过专

  15. Air purification by heterogeneous photocatalytic oxidation with multi-doped thin film titanium dioxide

    Energy Technology Data Exchange (ETDEWEB)

    O' Keeffe, Cormac, E-mail: [Theta Chemicals Ltd., Station Road, Ballindine, Claremorris, Mayo (Ireland); Gannon, Paul; Gilson, Paul [Theta Chemicals Ltd., Station Road, Ballindine, Claremorris, Mayo (Ireland); Kafizas, Andreas; Parkin, Ivan P. [Department of Chemistry, University College London, Christopher Ingold Laboratories, 20 Gordon Street, London WC1H 0AJ (United Kingdom); Binions, Russell [School of Engineering and Materials Sciences, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom)


    Multi element-doped titania films (F, S-TiO{sub 2}) were produced via sol–gel techniques and deposited on glass and ceramic substrates with an annealing temperature of 500 °C. The films were characterised by X-ray diffraction, Raman Spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscopy. The X-ray diffraction and Raman spectrum showed the films to have an anatase TiO{sub 2} structure with X-ray photoelectron spectroscopy confirming the presence of sulphur, fluorine and carbon doping. The titania coated glass and ceramic substrates were compared against two commercially available TiO{sub 2} coated products for the photo-destruction of NO{sub 2(g)}. The study included both equivalent indoor and outdoor test conditions. The multi-doped titania films were shown to provide a genuine method of air purification under both visible (room lighting) and UVA lighting with photo-destruction rates as high as 72%. - Highlights: • Synthesis of multi-doped titania films • Excellent NO{sub 2} conversion rates for coated ceramic tiles • Excellent NO{sub 2} conversion rates for coated glass substrates • Significantly better conversion rates for existing commercial products.

  16. An investigation of an underwater steam plasma discharge as alternative to air plasmas for water purification (United States)

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


    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.

  17. 三电极净化技术的应用研究%The Application Research of Ionic-driven Air Purification Technology

    Institute of Scientific and Technical Information of China (English)

    李军华; 陶孙华; 肖德玲


    主要分析三电极净化技术在产品上应用的可行性。首先通过各种实验测试评估此净化技术的净化性能,然后与其它净化产品进行性能对比分析,通过试验评估得出:三电离净化技术具有净化效果好,风阻低等优势,但电器安全性等方面需要进一步的评估。%The paper study the applied feasible of ionic-driven air purification technology. First, test the purification performance, Then contrast with the other purification product which is applied different purification methods. Draw a conclusion by test, purification performance is good and air resistance is low of ionic-driven air purification, but security performance need more test.


    Institute of Scientific and Technical Information of China (English)

    霍亭; 武兴斌; 韩莉


    The article briefly introduces the main sources of indoor polutants in public buildings; describes the types and working principle of air purification products; analyzes the requirements of medical buildings for air purification products and ranges of various air purification products applied within the hospital.%文章简单介绍了公共建筑室内污染物的主要来源;介绍了空气净化产品的种类及工作原理;分析了医疗建筑对空气净化产品的要求以及各类空气净化产品在医院内的适用范围。

  19. 室内空气污染及净化技术研究%Study of Pollution of Indoor Air and its Purification Technology

    Institute of Scientific and Technical Information of China (English)



    This article summarizes the sources of indoor air pollutants and the hazards to people's health. And then it analyzes the treatment effects of various purification technologies,which provides technical references for the development direction of indoor air purification technology.%综述了室内空气污染物的来源及其对人体健康的危害,通过对各种净化技术处理效果的综合分析,为室内空气净化技术的发展方向提供一些技术参考。

  20. 大型公共场所室内空气净化技术%Indoor Air Purification Technology in Large-sized Publics

    Institute of Scientific and Technical Information of China (English)

    陈健; 王健


      The paper presents the indoor air pol ution, particularly air pol ution problems in large-sized publics, the familiar air purification technology and development. The paper puts forward some suggestions in the field of air pol ution treatment and air purification technology application by analyzing the engineering examples.%  介绍了室内空气污染特别是大型公共场所的空气污染问题,以及常见的空气净化技术及发展情况,通过分析工程实例,提出了空气污染治理及净化技术应用的一些建议。

  1. 潜艇舱可移动式快速空气净化装置研究%Discussion on Portable and Fast Air Purification Technology

    Institute of Scientific and Technical Information of China (English)



      The air in the hermetic cabin of the submarine has poor quality, the air needs to be rapidly replaced after the fire accident hap⁃pened. According to the situation,the paper designed portable and fast air purification device, the smoke rapid purification simulation test. The test results showed that the air purification device can removed the fire smoke quickly and effectively. Based on the author's practical ex⁃perience, the paper put forward some technical indicators based on the portable and fast air purification device.%  针对潜艇舱室内空气质量较差、舱室内发生火灾事故后需要快速进行空气净化等问题,设计了可移动式快速空气净化装置,进行了烟雾快速净化模拟试验。试验结果表明,空气净化装置的内循环过滤通风可以快速有效地清除火灾后的烟雾。根据工作实践经验,对可移动式快速空气净化装置提出了几点技术指标要求。

  2. 室内空气的调节与净化案例%Indoor Air Conditioning and Purification

    Institute of Scientific and Technical Information of China (English)



    The indoor air quality has been paid closely attention recently, for some organics as VOC endangering human health through respiration and skin contact. Utilizing the adsorption and photo-catalysis function of purification nest and air conditioning technology, the pollution air occupied 350 m2 area office has been treated for a month. The result showed the air quality dramatically improved and met the national standard requirement.%近年来室内空气环境质量引起人们关注,挥发性有机物和甲醛等有机物通过呼吸和皮肤接触等方式危害人体健康.利用净化网的吸附和光催化功能和空调的调节作用,对占地面积350 m2办公楼室内的空气污染进行治理,运行时间1个月,室内空气质量得到明显提高,满足国家相关标准要求.

  3. Ventilation and Air Conditioning Design and Lampblack Purification in Kitchen%厨房的通风空调设计与油烟的净化

    Institute of Scientific and Technical Information of China (English)



    The article discussed system form,ventilation volume,airflow structure,kitchen air supply,fire smoke,exhaust purification in kitchen ventilation and air conditioning design.%主要论述了厨房的通风空调设计中系统形式、通风量、气流组织、厨房补风、防火排烟、排风净化等方面的问题。

  4. Investigation on the Effect of the Air Purification of Indoor green Wall%室内植物墙空气净化效果的研究

    Institute of Scientific and Technical Information of China (English)



    室内植物墙由于具有极高的观赏性和空气净化能力,近年来得到了人们的重视。对利用室内植物墙实现空气净化效果进行了深入研究,在保证植物墙正常存活的前提下,通过植物的选择、空气微循环的促进等手段提高植物墙的空气净化效果。对不同空气污染物进行了净化效果检测,结果表明室内空气净化植物墙可以有效降低室内各种有害空气污染物浓度。%Indoor green wal is attracting more attention of people in recent years due to its high ornamental value and air purifying ability. This article has conducted the thorough research on the implementation of air purification effect by indoor green wal . Under the premise of ensuring the normal survival of the plants, the effect of air purification of indoor green wal is improved through the selection of plants, air microcirculation and other means. The effect purification of different air pol utants is tested, and the results show that the indoor air purification green wal can effectively reduce al sorts of indoor harmful air pol utants concentration.

  5. Biological waste air purification - gases, odours, germs. Proceedings; Biologische Abgasreinigung - Gase, Gerueche, Keime. Tagungsband

    Energy Technology Data Exchange (ETDEWEB)



    As environment-friendly and energy-saving processes emerged during the past decades, valuable experience was gained in the practical application of biological waste purification, which is reflected in the VDI 3477 and VDI 3478 guidelines. The state of the art was documented and discussed in regular meetings. The interdisciplinary knowledge required made engineers, biologists, biochemists and metrologists get together in teams, which are now supplemented by experts in environmental and social medicine working on the quantification and assessment of the effects of bioaerosol emissions on the human body. This colloquium attempts a Europe-wide assessment of the practical performance of biological waste gas purification systems. Particular regard is given to the legal boundary conditions of off-gas purification and the licensing and monitoring of plants. New process variants are discussed. [German] Umweltfreundliche und energiesparende Verfahrenstechniken haben in den vergangenen Jahrzehnten einen bemerkenswerten Aufschwung erfahren. In dieser Zeit konnten wertvolle Erfahrungen bei der praktischen Anwendung u. a. der biologischen Abgasreinigung gesammelt und in den Richtlinien VDI 3477 und VDI 3478 niedergelegt werden. Ausserdem wurde in regelmaessigen Veranstaltungen der Stand der Technik und des Fortschritts dokumentiert und diskutiert. Durch die fuer dieses Taetigkeitsfeld nolwendigen interdisziplinaeren Kenntnisse sind Ingenieure, Biologen, Biochemiker und Messtechniker zu Teams zusammengewachsen. Als neue Berufsgruppe kommen jetzt Umwelt- und Sozialmediziner dazu, die insbesondere die Wirkung von Bioaerosolemissionen auf den Menschen quantifizieren und bewerten sollen. Dieses Kolloquium soll dazu dienen, einen Ueberblick ueber die europaweite Praxistauglichkeit der biologischen Abgasreinigungssysteme zu geben. Besonderes Gewicht wird auf die rechtlichen Rahmenbedingungen fuer die Abgasreinigung und auf die Genehmigung und Ueberwachung der Anlagen gelegt. Hinweise

  6. 空气净化技术现状及其发展趋势刍议%Discussion on Status and Development Tendency of Air Purification Technology

    Institute of Scientific and Technical Information of China (English)



    Firstly, the operating theory about several kinds of popular air purification technology is introduced in this paper. It also studied the advantages and disadvantages of these function in practical application. Secondly, it puts the emphasis on the new direction of air cleaning technology, and states the basic theory of water-washing air. Finally, the development trends of purification technology are discussed and summarized.%首先,介绍目前市场上流行的若干种空气净化技术工作原理,分析这些净化技术在实际应用中的优缺点。其次,重点阐述空气净化技术的新方向———“水洗空气”的基本原理,最后对净化技术发展趋势进行展望和总结。

  7. PTR-MS Assessment of Photocatalytic and Sorption-Based Purification of Recirculated Cabin Air during Simulated 7-h Flights with High Passenger Density

    DEFF Research Database (Denmark)

    Wisthaler, Armin; Strøm-Tejsen, Peter; Fang, Lei;


    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 prefil-ter; and a two-stage sorptionbased 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. Protontransfer 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 effi-ciently reduced by all three units. The photocatalytic units...

  8. Assessment of internal contamination problems associated with bioregenerative air/water purification systems (United States)

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


    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.

  9. Air purification: photo catalysis to fight smells; Epuration de l'air: la photocatalyse pour lutter contre les odeurs

    Energy Technology Data Exchange (ETDEWEB)

    Kartheuser, B. [Certech (Belgium)


    The insufficient ventilation of buildings and the emission of volatile organic compounds (VOCs) by the modern building materials are at the origin of the decay of the indoor air quality. The photo-catalysis is a technique that can ensure a complete destruction of the air pollutants. This technique uses a semiconductor material (in general TiO{sub 2}) and a light radiation (UV or visible). When submitted to the light radiation, the semiconductor material produces highly-oxidizing radicals which allow the destruction of the pollutants adsorbed on its surface. A new configuration of photo-catalytic reactor has been developed by the Certech (centre of technological resources in chemistry) which allows to process the air of a 40 m{sup 3} room with a 100 W power consumption. This system has many other advantages, like: very good efficiency with low cost commercial catalysts, reaction at ambient temperature and pressure, compactness etc.. (J.S.)

  10. Effect of charcoal on water purification


    Suzuki, Hirotaka; Kawahigashi, Tatsuo


    [Abstract] A natural basin system purifies water through self-purification, but the water pollution load of a river might exceed its self-purification capacity. Charcoal, which is used for other uses aside from heating, such as air purification, was evaluated experimentally for water quality purification. The experiment described herein is based on simple water quality measurements. Some experimentally obtained results are discussed.

  11. 空气预纯化的技术研究进展%Progress in air pre-purification technology

    Institute of Scientific and Technical Information of China (English)

    王浩宇; 刘应书; 杨雄


    This paper reviewed recent developments and industrial applications of air pre-purification. Currently pressure equalization and multi-bed cycle are mostly commonly adopted in technological process,but the system has problems of large dimensions and complex process. Single adsorbent, mixed adsorbent or composite adsorbent are mainly used in gas purification,but the desired effect has not been obtained. Vertical-axial flow absorber,horizontal-vertical flow absorber and vertical-radical flow absorber are mostly used as absorber structures. The adsorption efficiency can be enhanced by improving air distributor,molecular sieve layout and packing etc,but it is impaired by some factors such as space and energy consumption. Air pre-purification technology will be further studied with improvement of process and a new module process system,modification of the original adsorbent and searching for new adsorbent,improvement of the structure of absorber and finding new structure.%空气预纯化在空分设备流程中起着保障整套设备安全运行的重要作用。本文综述了近年来国内、外空气预纯化技术的研究和应用情况。指出目前目前存在的问题是:工艺流程大多通过增加均压、多塔循环等工艺步骤来提高空气预纯化效果,但系统尺寸较大、流程较复杂;吸附剂大多采用单一吸附剂、几种混合吸附剂或复合吸附剂来纯化气体,但纯化效果不理想且成本较高;吸附器大多采用立式轴向流、卧式垂直流、立式径向流等结构,通过改进气流分布器、改善分子筛布局及装填方式等提高吸附效率,但受到场地、能耗等因素限制。未来的研究重点应放在工艺流程的改进及开发新型模块式流程系统、原有吸附剂的改性及寻找新型吸附剂材料、原有吸附器结构的改进及开发新型吸附器结构等方面。

  12. 煤矿避难硐室空气净化装置布局研究%Study of Air Purification Device Layout in Coal Mine Refuge Chamber

    Institute of Scientific and Technical Information of China (English)



    根据物质守恒定律,推导出避难硐室内有害气体浓度计算表达式,确立了避难硐室内净化需风量与有害气体控制浓度及室内避灾人数的数学关系。利用Fluent软件分析了51型避难硐室内净化装置3种不同工况下,室内的空气流速分布和CO2气体浓度分布,得出2台净化装置可将室内CO2体积分数控制在0.50%以下,满足避难硐室空气净化要求。%In this PaPer,a calculation exPression for the harmful gas concentration in the refuge chamber was deduced according to the law of conservation of matter,and the mathematical relationshiP of the required air quantity for Purification in the refuge chamber with the control of the harmful gas concentration and number of the Persons stayed in the chamber was established. With Fluent software,analysis was made on the distribution of the air flow rate and CO2 concentration in the refuge chamber under three different oPeration conditions of 51-tyPe chamber Purification device. It came to a conclusion that using two air Purification devices could control CO2 volume fraction below 0. 50% and meet the air Purification requirement in the refuge chamber.

  13. Artificial intelligence modeling to evaluate field performance of photocatalytic asphalt pavement for ambient air purification. (United States)

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


    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.

  14. Highly efficient indoor air purification using adsorption-enhanced-photocatalysis-based microporous TiO2 at short residence time. (United States)

    Lv, Jinze; Zhu, Lizhong


    A short residence time is a key design parameter for the removal of organic pollutants in catalyst-based indoor air purification systems. In this study, we synthesized a series of TiO2 with different micropore volumes and studied their removal efficiency of indoor carbonyl pollutants at a short residence time. Our results indicated that the superior adsorption capability of TiO2 with micropores improved its performance in the photocatalytic degradation of cyclohexanone, while the photocatalytic removal of the pollutant successfully kept porous TiO2 from becoming saturated. When treated with 1 mg m(-3) cyclohexanone at a relatively humidity of 18%, the adsorption amount on microporous TiO2 was 5.4-7.9 times higher than that on P25. Removal efficiency via photocatalysis followed'the same order as the adsorption amount: TiO2-5 > TiO2-20 > TiO2-60 > TiO2-180 > P25. The advantage of microporous TiO2 over P25 became more pronounced when the residence time declined from 0.072 to 0.036 s. Moreover, as the concentration of cyclohexanone deceased from 1000 ppb to 500 ppb, removal efficiency by microporous TiO2 increased more rapidly than P25.

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



    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 ind...

  16. Photocatalysis for continuous air purification in wastewater treatment plants: from lab to reality. (United States)

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


    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).

  17. Design approaches for a cycling adsorbent/photocatalyst system for indoor air purification: formaldehyde example. (United States)

    Chin, Paul; Ollis, David F


    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.

  18. Air purification from TCE and PCE contamination in a hybrid bioreactors and biofilter integrated system. (United States)

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


    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.

  19. Are TiO2 Nanotubes Worth Using in Photocatalytic Purification of Air and Water?

    Directory of Open Access Journals (Sweden)

    Pierre Pichat


    Full Text Available 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.


    Institute of Scientific and Technical Information of China (English)



    目的 观察空气消毒机对医院手术室空气消毒效果,以评价其实际应用效果.方法 采用平板沉降采样和细菌培养方法,评价该多因子组合空气净化装置对手术室空气中自然菌净化效果,并与紫外线灯照射消毒作平行比较.结果 启动YKX/Y型空气消毒机和紫外线灯作用30 min,5 min后采样,手术室空气中细菌总数<200cfu/m3,随着时间的延长,空气中菌数逐渐增加,15 min后细菌总数逐渐增加到200 cfu/m3以上.在手术室有6人工作的情况下,空气消毒机持续运行,可使空气细菌继续保持在<200 cfu/m3.结论 试验用空气消毒机可以在手术期间持续消毒,可以维持手术室内空气中细菌总数< 200 cfu/m3.%Objective To observe the air disinfection effect in the operating room of hospital by using the local air purification device and evaluate the practical application effect of the device. Methods By using the methods of tablet settlement sampling and bacterial culture, to evaluate and compare the effect of air purification in the operating room by the air purification device and ultraviolet light irradiation. Results 5 mins later after using the air disinfection device of YKX / Y - type and the ultraviolet ray lamp for 30 mins, the total number of bacteria in the air of operating room was less than 200 cfu/m3. As the time prolonged to 15 min, the bacteria number increased to more than 200 cfu/m3. Under the condition of six persons working and the air disinfection device running continuously in the operating room, the bacteria in the air maintained less than 200 cfu/m3. Conclusion The air purification device can continue disinfection during surgical operation and the number of bacteria can maintain less than 200 cfu/m3.

  1. Visible Light Responsive Catalysts Using Quantum Dot-Modified Ti02 for Air and Water Purification (United States)

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


    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.

  2. In Low Temperature Purification Workshop Air Conditioning Design Analysis%低温净化车间空调设计分析

    Institute of Scientific and Technical Information of China (English)



      In some production enterprises, because of its p-roducts having a low temperature, clean requirements, there-fore, it is necessary to have the air conditioning system which can meet the needs in the production process. However, because of in the low temperature purification workshop air conditioning system requirements relatively high, and the system design difficulty oppositely bigger, in order to meet the needs of actual production, this paper puts forward a kind of low temperature purification of airconditioning system design scheme. Based on this point, this paper make research on cryogenic purification workshop air conditioning system design.%  在一些生产企业中,由于其生产的产品对环境有着低温、洁净的要求,为此需要在这样的车间中配置能够满足生产工艺需求的空调系统。然而,因为低温净化车间对空调系统的要求相对较高,致使系统的设计难度相对较大,为了满足实际生产需要,提出了一种低温净化空调系统的设计方案。基于此点,本文就低温净化车间空调系统设计展开研究。

  3. Digital Speed Control System Design for Air Purification Equipment%空气净化装置数字化调速控制系统设计

    Institute of Scientific and Technical Information of China (English)

    石宝松; 张伟; 刘剑; 韩振伟


    地平式激光跟踪发射系统为保证其光路洁净,须进行正压防尘处理。针对外购空气净化设备仅能采用手动风速调节,不能实现计算机远程控制的不足,研发了空气净化设备数字化调速控制系统,以实现对空气净化装置的远程控制与状态监测。本设计采用光电隔离单相交流调压模块实现对风机的驱动,采用霍尔电流传感器实现对风机的电流测量,并采用内部集成A/D转换器和D/A转换器的单片机通过RS422总线接收控制指令,完成对调压模块的输出功率控制和风机电流的实时采集。本系统设计简洁、控制方便、运行可靠、易于维护,实现了设备管理计算机对空气净化设备风速的远程控制。%Horizon emitting laser tracking system to ensure its optical path cleaning, shall be positive dust treatment. For the lack of air purification equipment purchased only with manual speed adjustment and the remote control of a computer can not be achieved, we have developed an air purification equipment digital speed control system to achieve the remote control and status monitoring of air purification device. The design uses a optically isolated single-phase AC voltage regulator module for fan drive,uses a Hall current sensors to achieve the fan current measurement,and uses a microcontroller, which integrates a A/D converter and a D/A converter, to receive the control command via the RS422 bus, to complete the output power control of voltage regulator module, and to realize the real-time collection of fan’ s current. The system is designed to be simple, easy to control, reliable to operate and easy to maintain and realizes the remote control of a device management computer on the wind speed of air purification equipment.

  4. MP2.5对人体的影响及净化--浅谈 PM2.5对人体健康的影响及空调的空气净化对建筑物室内空气品质的论证%The Effection of MP2.5 on Human Body and Purification--On PM2.5 Effects on Human Health and the Argument of Air Conditioning Air Purification for Buildings Indoor Air Quality

    Institute of Scientific and Technical Information of China (English)



      本文就中国目前糟糕的空气质量和时下最为大众关注的 PM2.5问题,以及空气质量对人体健康的影响,论证空调净化空气尤其是 PM2.5的可行性。通过分析我国空气质量现状以及空调的空气净化功能,指出空气品质对于生活工作在建筑内的人的健康的影响,提出通过空调净化空气 PM2.5值到适宜人类居住标准的方案。%This paper talks about the most popular concerned PM2.5 problem of China at present poor air quality, and the in-fluence of air quality on human health, demonstrates air puri-fycation especial y the feasibility of PM2.5. Through the ana-lysis of the status of China's air quality and air conditioning air purification function, pointes out that the impact on air qualit-y for living and working in the construction of human health, puts forward by air purification air PM2.5 value to the habitab-le standard solution.

  5. 避难硐室气体净化理论分析与试验研究%Theoretical Analysis and Experimental Study of Air Purification in Refuge Chamber

    Institute of Scientific and Technical Information of China (English)

    陈于金; 许凯


    根据避难硐室CO2、CO气体快速净化要求,理论分析计算了净化所需风量及空气净化装置数量。以50人避难硐室为试验平台,对CO2、CO进行了快速净化能力测试,并通过50人8 h真人试验测试,得出避难硐室有害气体浓度变化曲线及轻度劳动条件下单人代谢CO2和CO的速率。结果表明:3台空气净化装置能够满足50人避难硐室CO2快速净化及CO2、CO实际真人净化要求。对于CO快速净化,还应增加空气净化装置数量,增大空气净化风量。%Theoretical calculation and analysis were made on the air quantity and the number of air purification devices required for air purification according to the rapid purification requirements for CO2 and CO in the refuge chamber. The test of rapid purification capacity for CO2 and CO was carried out by taking a 50-person refuge chamber as the test platform, and through the test of 50 persons staying in the refuge chamber for 8 hours, the variation curve of the harmful gas concentration in the chamber and the metabolic rate of CO2 and CO by a single person under the condition of light labor intensity were obtained. The results showed that three air purification devices could meet the requirements for the rapid purification of CO2 in a 50-person refuge chamber and the purification requirements for CO2 and CO produced by real persons. For the rapid purification of CO, it should increase the number of the air purification devices and the air quantity.

  6. Studies on Oxygen Characteristics of YBa2Cu3O7-x and Its Applications to Air Separation and Gas Purification

    Institute of Scientific and Technical Information of China (English)

    Yang Delin; Mo Jiong; Lu Hongxia; Guo Yiqun; Gao Zhishuang; Hu Xing


    Oxygen diffusion and oxygen selective adsorption properties of rare earths material YBa2Cu3O7-x (YBCO) were investigated by thermogravimetric, oxygen static adsorption and selectivity adsorption experiments. The results show that YBCO is a very good deoxidizing material. The oxygen desorption of YBCO begins remarkably at about 400 ℃, mass loss can arrive at 1.2% of its original quantity at 800 ℃. Oxygen can be completely absorbed back into the sample again when temperature descends to 400 ℃. The oxygen adsorption selectivity, reproducibility and oxygen adsorption under very low oxygen partial pressure make the material desirable for air separation and gas purification. High purity nitrogen gas was produced with the YBCO molecular sieves in the air separation and gas purification experiments. 0.017 m3 of high purity nitrogen (>99.9999%) can be obtained with 1 kg YBCO molecular sieve in one cycle. As a deoxidant, an obvious advantage of YBCO is that no hydrogen is needed in its applications.

  7. Air Purification of Urban Underground Space%城市地下空间空气净化处理探讨

    Institute of Scientific and Technical Information of China (English)

    沈洪; 张美玲; 王嘉


    近年来空气污染严重,在室外雾霾大环境下,如何确保室内空气品质不受影响是人们密切关注的问题。以地下空间为例,分析了室内环境中的颗粒物及有害气体的主要来源,并提出了其净化处理方法,即通过中央空调系统空气净化装置来改善室内空气品质。%In recent years, air pollution is serious, under the outdoor environment of haze, ensuring indoor air quality is an crucial issue. Taking the underground space as an example, main sources of particulate matter in the indoor environment and harmful gases are analyzed, and the purification method is presented, namely through air cleaning devices of the central air conditioning system to improve indoor air quality.

  8. Controlling Points of Air Purification System in Design and Construction Process%净化空调系统在设计施工过程中的控制要点

    Institute of Scientific and Technical Information of China (English)



    随着高新技术的发展,对生产环境的洁净要求也越来越严格,净化空调的应用越来越广泛。该文在阐述洁净等级的划分之后,根据实际经验提出净化空调系统设计存在的问题,并分析了系统施工过程应注意的问题。%With the development of high and new technology, requirements on production environment are getting increasingly stricter, and application of air purification system is also getting increasingly wider. The classification of purification level is elaborated, the existing problems in air purification sys-tem design are presented in accordance with actual experience and some attention worth issues in construction process are also analyzed.

  9. The Home Air Quality Purification System Based on Internet of Things%基于物联网的家居空气质量净化系统

    Institute of Scientific and Technical Information of China (English)

    蔡文郁; 徐建军; 王洪亮


    For the current status of air pollution and the demand for healthy indoor environment,the paper studies a type of home purification system which based on the internet of things (IoT).The system uses the ARM-Cortex-M0 core micro-controller NuMicro-M058 as the hardware platform,and RTX embedded operating system as the software platform,with three filters,a variety of purification photo catalytic disinfection,ultraviolet disinfection,etc.The air purifier also has a collection function for air quality data such as PM2.5,VOC,temperature and humidity.It also can connect through the server and mobile client applications to implement remote monitoring.%针对目前大气污染的现状和人们对健康室内环境的需求,研究并设计了一种基于物联网的家居空气质量净化系统.系统以 ARM-Cortex-M0内核微控制器 NuMicro-M058芯片为硬件核心,采用嵌入式 RTX 操作系统为软件平台,具有三层滤网、光触媒消毒、紫外线杀菌等多种净化功能,而且还具有 PM 2.5,VOC,温湿度等空气质量数据采集功能,最终通过服务器与手机端程序的编写实现了物联网化远程监控.

  10. Experimental Study on Air Purifier's Purification Efficiency for Indoor Formaldehyde%空气净化器对室内甲醛净化效果的实验研究

    Institute of Scientific and Technical Information of China (English)

    胡俊; 肖江蓉; 李亮亮; 周胜银; 彭天右


    By using formaldehyde as the objective volatile pollutant, the purification efficiencies of some representative air purifiers were determined under the relatively independent and stable environmental conditions supplied by the self-made multifunctional environmental test chamber. The clean air delivery rate(CADR), purification efficiency and removal rate of formaldehyde were also calculated based on the tested results. It was found that the formaldehyde purification efficiency obviously decreased with enhancing the relative humidity, and gradually increased with enhancing the air flow rate, whereas the effect of temperature on the purification efficiency was limited. Moreover, the air purifier based on integration of manifold purification techniques showed better purification efficiency as compared to that based on single adsorption purification technique. The above results indicate that keeping indoor dryness and ventilation as well as integrated manifold purification techniques are beneficial for the improvement of purification efficiency.%利用研制的多功能环境试验舱提供相对独立和稳定的环境条件,以甲醛为挥发性目标污染物,对所选取的代表性空气净化器的甲醛净化效果进行测试,计算了空气净化器对甲醛的洁净空气量,净化效率和去除率等.结果表明,空气净化器对甲醛净化效率随着相对湿度的增大而明显降低,随着空气流速的增大而有所提高,而室内温度对其影响并不明显.采用物理和化学净化技术相结合的空气净化器的甲醛净化效率明显优于采用单一的物理吸附净化技术的空气净化器.

  11. 北京市住宅空气质量及相关能耗调查及分析%Investigation and Analysis of Indoor Air Quality and Energy Consumption of Air Purification in Beijing

    Institute of Scientific and Technical Information of China (English)

    李娜; 张博; 杨红; 黄文霞


    近年来,我国北方地区空气污染问题日益严重,频频发生的雾霾现象使得人们越来越重视室内空气质量。调查了北京市部分家庭对雾霾的认知以及所采取的改善室内空气质量的措施。发现未来2~3年内将会有72.8%的家庭采用空气净化器来改善室内空气质量,并由此推算出全年北京市住宅用于空气净化的建筑能耗量。%In recent years, the problem of air pollution in northern China has become increasingly serious. Frequent occurrence of fog and haze forces people to pay more and more attention to indoor air quality. This paper investigated the cognition of haze in several families in Beijing and their methods to improve indoor air quality. This research found that, within the next two or three years, there will be 72.8%of families using the air purifier to improve indoor air quality, and thus it calculated the annual Beijing residential building energy consumption for air purification.

  12. Effects of Two Kinds of Air Purification in NICU Ward%两种不同空气净化方式对NICU病房的影响

    Institute of Scientific and Technical Information of China (English)

    洪素蜜; 黄跃兴


    目的比较不同空气净化方式对病房医院感染的影响,探讨更适合NICU病房空气质量的管理办法。方法在同个季度的不同月份采用两种不同的空气净化方式,平板自然沉降法检测病房内空气净化后的细菌总数,监测各个月份医院感染发生情况,应用SPSS 10.0统计分析。结果采用自然通风换气与空气消毒机消毒后病房的细菌总数比较没有显著性差异(﹥0.05),两种方法而发生医院感染率同样没有显著性差异(﹥0.05)。与空气消毒机净化室内空气方式比,采用自然通风方式时病房患儿平均住院日数更短,平均少0.93d。结论在自然通风良好的状态下,做好通风时间对患儿的保暖,在NICU病房采用合理的自然通风可能对患儿的康复更有利。%Objective To compare the influence of dif erent air purification way about hospital infection, explore more suitable measures for the administration of NICU ward air quality. Methods In the same quarter of dif erent months using two dif erent ways of air purification, use the method of flat natural sedimentation to monitoring the ward air after purification, the total number of bacteria, hospital infection occurred in monitoring the situation, application of spss10.0 statistical analysis.Results After using natural ventilation and Air disinfection machine to disinfection ward of the total number of bacteria is no significant dif erence ( ﹥0.05), two methods and the hospital infection rate is also no significant dif erence( ﹥0.05). compare with air purifying indoor using air disinfection machine, natural ventilation mode can shorter average hospital stay, an average of 0.93 days.Conclusion Under the conditions of natural ventilation, keep children warm when ventilated time , employing reasonable natural ventilation in the NICU ward might be more beneficial to the patient's recovery.

  13. Regenerative thermal purification of waste air using the pebble heater technology; Regenerative Thermische Abluftreinigung mit der Pebble-Heater-Technologie

    Energy Technology Data Exchange (ETDEWEB)

    Stevanovic, D.; Kapp, R. [Applikations- und Technikzentrum fuer Energieverfahrens-, Umwelt- und Stroemungstechnik (ATZ-EVUS), Sulzbach-Rosenberg (Germany); Rueskamp, B. [Lufttechnik Bayeurth, Goldkronach (Germany)


    Regenerative thermal post-combustion systems are used for purification of different types of process gases. They are getting increasingly important as legal specifications are getting more rigid. Low-cost solutions are sought for in an attempt to keep the investment cost and operating cost at a low level. [German] Regenerative thermische Nachverbrennungsanlagen werden fuer die Abreinigung verschiedenartiger Prozessgase genutzt. Sie werden immer wichtiger, weil sie die inzwischen sehr strengen gesetzlichen Richtlinien erfuellen. Um Investitions- und Betriebskosten niedrig zu halten, wird auch hier nach kostenguenstigeren Loesungen gesucht. (orig.)

  14. 溶气法在糖汁(浆)气浮清净工艺中的应用%Application of the Dissolved-air Flotation Technology in the Cane Juice Purification Process

    Institute of Scientific and Technical Information of China (English)



    This paper introduces the dissolved-air flotation technology and the design of the key equipment, and analyses the application of the dissolved-air flotation technology in the flotating purification process of cane juice. The results showed that the best choice is to exploit the pressed dissolved-air flotation technology for the flotating purification process of diluted cane juice.%介绍了溶气上浮法的工艺流程及主要设备的设计并分析了其应用效果。生产实践表明,利用溶气法进行充气打泡是稀汁气浮清净工艺的最好选择。

  15. Study of Purification Effects of Air Cleaners with Non-thermal Plasma on Indoor Particular Matter%含NTP技术净化器对室内颗粒物的净化效果

    Institute of Scientific and Technical Information of China (English)

    陆海全; 丁志威; 颜凯; 梅敏花; 郭婷; 钟依均; 谢云龙


    选择几款国内含有低温等离子体( Non-thermal plasma, NTP)技术的空气净化器( air cleaner)样机,以香烟烟雾为净化对象,研究其对室内空气中颗粒物的净化效果。结果表明,所选用空气净化器对100 nm以上颗粒物有一定的去除效果,对100 nm以下的颗粒物几乎没有净化效果;单一采用低温等离子体净化技术对颗粒物的去除不理想;高效粒子过滤器( HEPA, High efficiency particulate air Filter)对颗粒物的净化起着关键作用。%Using cigarette smoke as the purification target, the purification effects of several residential air cleaners containing non-thermal plasma ( NTP) technology on indoor particulate matter in air were studied. The results showed that the selected air cleaners had a certain effect on removal of particles above 100 nm while had few effects for particles below 100 nm. Single use of NTP purification technology was not effective to remove particulate matter. HEPA technology played a key role in eliminating the particulate matter.

  16. 某移动式空气净化消毒机对室内空气净化的效果分析%Effect Analysis of A Portable Air Purification and Disinfection Machine Indoor Air Purification

    Institute of Scientific and Technical Information of China (English)

    张广伟; 张濛; 胡巅; 张丁


      Objective Test the disinnfection of bacteria in indoor air for air disinfection machine, to verify its effectiveness to air disinfection. Methods According to“Technical Standard For Disinfection”(2002)“Identification of air disinfection on the spot”. Results After the air disinfection machines disinfect air 30 mins in the ICU of the hospital, the disappearance rates of natural bacteria in indoor air were 91.45%(low rank) and 99.38%(high rank) respectively. Conclusion The clearance of the natural bacteria in air of hospital classⅡenvironment for the air disinfection machine meets the requirement of"Technical Standard For Disinfection"(2002) .%  目的检测某品牌移动式空气净化消毒机对室内空气中细菌的清除作用,以验证其对空气消毒的效果.方法《消毒技术规范》(2002)空气消毒效果鉴定现场试验.结果该空气净化消毒机对医院ICU病房中的空气消毒作用30min,室内空气中自然菌的消亡率分别为91.45%(低档)、99.38%(高档).结论该移动空气净化消毒机对医院Ⅱ类环境空气中自然菌的清除符合《消毒技术规范》(2002)的要求.

  17. Experimental investigation of the formaldehyde removal mechanisms in a dynamic botanical filtration system for indoor air purification. (United States)

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


    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.

  18. Progress on Technology of the Air Disinfection and Purification in Medical Institutions%医疗机构空气消毒净化处理技术进展

    Institute of Scientific and Technical Information of China (English)



    In view of the airborne disease has become the top transmitting disease in the world, the air disinfection and purification is more important and urgent.The indoor air disinfection and purification is an effective and important measure for interruption of spread of respiratory infectious diseases.In order to guide the daily work, this article summarizes the technology and methods of indoor air disinfection and purification from domestic and foreign medical institutions in recent years.The technology and methods are illustrated in two conditions, including circumstance with or without people.In circumstance with people, the medical institution could adopt the following methods: high-efficiency particulate air filtering sterilization, high-voltage electrostatic adsorption sterilization, plasma technology, dynamic air disinfecting machines, air purification by nano-photocatalyst materials, air purification by artificial anion and construction laminar flow cleaning sterilization, etc.In circumstance without people, the medical institution could adopt the methods of ultraviolet irradiation and ozone disinfector.%鉴于经空气传播的疾病已占世界传播疾病的首位,凸显出空气消毒净化处理的重要性和紧迫性,而室内空气消毒净化处理是有效阻断呼吸道传染病传播的重要措施.作者重点归纳了近年来国内外有关医疗机构室内空气消毒净化处理的技术方法,意义在于更好地指导日常工作,技术方法主要对有人状态和无人状态2种情况分别进行了阐述.在有人状态下,可采用高效颗粒空气过滤净化除菌、高压静电吸附除菌、等离子体技术、动态空气消毒机、纳米光催化材料的空气净化、人工负离子空气净化和建筑型层流洁净除菌等技术方法处理.在无人状态下,可采用紫外线照射法和臭氧消毒机等技术方法处理.

  19. The purification effects of two air purificants to the volatile pollutants in tunnels%两种空气净化剂对坑道挥发性污染物的净化效果研究

    Institute of Scientific and Technical Information of China (English)

    周东明; 郁兴明; 唐雨德


    目的 观察选取的两种空气净化剂对坑道内挥发性污染物氨气和硫化氢的净化效果.方法 将植物空气净化剂及竹炭滤料分别放入密闭的容积为1m3的小型环境舱内,用采样器往其中吹入有害气体,用风扇混匀后测定空间内有害气体的浓度,每0.5h分别观察空气净化剂对几种挥发性污染物的净化率.结果 植物空气净化剂对氨气和硫化氢的两小时最大净化率分别为50%和37.5%,竹炭滤料净化剂对氨气和硫化氢的两小时最大净化率分别为60%和62.5%.结论 选用的两种空气净化剂对坑道挥发性污染物氨气和硫化氢都有较好的净化效果,可以用于坑道内有害气体的消除.%Objective To observe the purification effects of two different air purificants on the volatile pollutants ( NH3 and H2S) in tunnels. Methods The plant air purificant and the bamboo charcoal were put into a 1 m3 box of airtight minitype environment, respectively. The harmful gases were insufflated into the box with sampling implement and mixed them. At an interval of half an hour,the concentration of harmful gases was mensurated to observe the purification rates of two air purificants. Results The maximal purification rates of the plant air purificant to NH3 and H2S in 2 h were 50% and 37.5% ,respectively. The maximal purification rates of the bamboo charcoal air purificant to NH3 and H2S in 2 h were 60% and 62.5% ,respectively. Conclusion The purification effects of two air purificants are preferable to the volatile pollutants ( NH3 and H2S) in tunnels.The air purificants can effectively eliminate the harmful gases in tunnels.

  20. The species and distribution of air purification plants in Shijiazhuang urban area%石家庄市区空气净化植物的种类及分布研究

    Institute of Scientific and Technical Information of China (English)

    石金秋; 万五星; 宋雅丽


    By the investigation of the wild and cultivated plants in Shijiazhuang, the species, distribution and functions of the air purification plants are analyzed. Based on the results a number of recommendations about development, utilization and protection of air purification plants in Shijiazhuang urban area are provided.%通过对石家庄市区野生和栽培植物的调查,对有空气净化作用的植物种类、分布及功能进行分析,提出了石家庄市空气净化植物的开发利用和保护发展的若干建议.

  1. Discussion on Purification Performance Evaluation Methods of Car Air Purifier%对车载空气净化器净化性能评价方法的探讨

    Institute of Scientific and Technical Information of China (English)

    杨瑾; 闻真; 孙立


    30 car air purifiers (in view of family car) are selected in 3 m3 experiment module for testing, clean air delivery rate (CADR) and purification efficiency are used to evaluate the purifying effect of car air purifier on formaldehyde and particle pollutants, and the paper discusses the method differences. Testing result shows that it is proportional to both of them, when CADR formaldehyde≥12 m3/h and CADR particles≥15 m3/h, CADR can reflect the differences in purification capacity, and it can help consumers understand the real purification capacity of car air purifier in combination with purification efficiency.%选取30个车载空气净化器(针对家庭用车)在3 m3实验舱中进行测试,通过“洁净空气量(CADR)”和“净化效率”2种方法来评价车载空气净化器对甲醛及颗粒物污染物的净化效果,并就方法的差异展开探讨。检测结果表明,两者成正比关系,当CADR 甲醛≥12 m3/h、CADR 颗粒物≥15 m3/h时,CADR更能体现净化能力差异,结合净化效率,能帮助消费者了解车载空气净化器真实的净化能力。

  2. Fresh air purification and indoor air quality of the residential house%住宅新风净化与室内空气品质

    Institute of Scientific and Technical Information of China (English)

    刘飞; 刘颖


    通过对南京和上海的各两台新风机组处理段的颗粒分布和 PM10,PM2.5的浓度测试,分析了新风机组过滤器的性能以及过滤器的布置位置对新风品质的影响,并根据各处理段颗粒物浓度变化情况研究了影响室内空气品质的因素,以不断完善与优化新风空调过滤系统的性能。%Based on particle distribution and PM10 and PM2. 5 concentration testing of two new fresh air units in Nanjing and 2 fresh air units in Shanghai at various treatment phases,the paper analyzes whether the new fresh air unit filter performance meets demands and the impact of filter distribution upon new fresh air quality. According to particle concentration varying conditions at various treatment phases,it discusses factors in-fluencing indoor air quality,with a view to continuously improve and perfect new fresh-air-conditioning filtering properties.

  3. Effects of Gas-Phase Adsorption air purification on passengers and cabin crew in simulated 11-hour flights

    DEFF Research Database (Denmark)

    Strøm-Tejsen, Peter; Zukowska, Daria; Fang, Lei


    In a 3-row, 21-seat section of a simulated aircraft cabin that had been installed in a climate chamber, 4 groups of 17 subjects, acting as passengers and crew, took part in simulated 11-hour flights. Each group experienced 4 conditions in balanced order, defined by two outside air supply rates (2.......4 and 3.3 L/s per person), with and without a Gas-Phase Adsorption (GPA) unit in the re-circulated air system. Objective physical and physiological measurements and subjective human assessments of symptom intensity were obtained. The GPA unit provided advantages with no apparent disadvantages....

  4. Preparation of in situ secondary synthesis of indoor air purification functional fabric at low temperature%低温原位二次合成法制备室内空气净化功能织物

    Institute of Scientific and Technical Information of China (English)

    王振华; 刘保江; 何瑾馨


    Air purification functional fabric with practical value was prepared using in situ secondary synthesis method at low temperature.The surface morphology of air purification functional fabric was characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), atomic force microscopy (AFM) and X-ray diffraction (XRD).The good air purification ability of the treated fabric was confirmed by the degradation test of formaldehyde.In addition, the strength of TiO2 secondary synthesized cotton fabric distinctly increased,and the fabric showed excellent UV irradiation protection properties.%以低温原位二次合成法,制备了具有实用价值的空气净化功能织物.利用扫描电镜(SEM)、能谱分析(EDS)、原子力显微镜(AFM)和X射线衍射(XRD)表征空气净化功能织物表面的形态结构,并通过甲醛降解试验证明了其具有较好的空气净化能力.此外,棉织物经TiO2低温原位二次合成后强73增加明显,且具备极佳的紫外线防护特性.

  5. Application and progress on study of air purification with membrane separation process%膜分离法空气净化的应用与研究进展

    Institute of Scientific and Technical Information of China (English)



    气体膜分离技术已经成为空气净化的重要技术之一。文章全面综述了近年来的膜法空气净化技术的应用及研究进展,介绍了用于空气净化的分离膜及膜分离工艺,展望了膜法空气净化技术的发展趋势。指出,由于膜分离空气净化工艺具有连续操作、低能耗和高效等优点,有望替代或部分替代传统空气的颗粒物分离、脱湿及脱二氧化碳过程。%The gas membrane separation technology becomes one of important air purification technologies. Here, the application and progress on study of membrane air purification technology in the last years, the separation membrane used in air purification and the

  6. Visible-Light Responsive Catalysts Using Quantum Dot-Modified TiO2 for Air and Water Purification (United States)

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


    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.

  7. 应用负高压脉冲技术提高植物空气净化能力的探讨%Application of Negative High-voltage Pulse Technology to Improve Air Purification Ability of Plants

    Institute of Scientific and Technical Information of China (English)

    杨运经; 习岗; 刘锴; 张晓辉


    现代城市中的室内空气污染日益严重,室内空气污染的净化与治理已成为社会发展中迫切需要解决的关键科技问题之一.为此,根据植物电信号的低频特征与电共振原理,利用极低频负高压脉冲连续刺激盆栽吊兰植物的根际土壤,使吊兰叶片产生了显著的空气负离子倍增效应.在此基础上依据评价空气质量的常用指标:单极系数q、安培空气质量评价系数CI、空气负离子系数P和森林空气离子评价指数FCI,对应用负高压脉冲技术提高植物的空气净化能力进行了计算与分析.结果表明,极低频负高压脉冲电场可以有效地提高植物的空气净化能力,提出了极低频负高压脉冲电场介导的植物空气净化新技术.%Purification of indoor air pollution has become one of the key technologies of social development. An extremely low frequency high voltage pulse generator was designed according to the characteristics of plants electrical signals and the principle of electrical resonance. The soil of potted broadleaf bracket-plant (Chlorophytum como-sum) was continuously stimulated by negative high voltage pulses with very low frequency, the high concentration of negative air ions appeared around the plant leaves, and the multiplier effect of negative air ion from leave of broadleaf bracket-plant was produced. Then, the ability of plant air purification was calculated and analyzed according to common evaluation indicators of air quality such as single polar factor q, air quality assessment coefficient CI, negative ion air coefficient P and the forest air ion evaluation index FCI. The results show that the extremely low-frequency negative high voltage pulse can enhance the ability of plant to air purification. A new technology of indoor air pollution control and restoration based on negative high-voltage pulse technology is proposed.

  8. 一种新型空气消毒净化设备的消毒效果观察%Disinfection effects of a new type of air disinfection and purification equipment

    Institute of Scientific and Technical Information of China (English)

    谈书勤; 罗雅丽; 谢昭聪; 胡贵方; 顾大勇


    Objective: To investigate the indoor air disinfection effects of a new type of air disinfection and purification equipment based on high - voltage pulsed electric field sterilization technology. Methods: Experiments on the disinfection effects were carried out under the laboratory simulation and field test. Results: The new high - voltage pulsed electric field sterilization technology - based air sterilization purification equipment produced an average killing rate of 98.62%, 98.65% and 97.93%, respectively for artificial simulated aerosol of Serratia marcescens, Staphylococcus albus and Candida albicans in the laboratory simulation test, and 90.58% for the natural bacteria aerosols in the port field test. Conclusion: Under specified using conditions, the new high - voltage pulsed electric field sterilization technology - based air sterilization purification equipment had a great killing effect on air microbial aerosols, and was worthy to promote as a new type of air disinfection and purification equipment.%目的:观察基于高压脉冲电场杀菌技术的新型空气消毒净化设备对室内空气的消毒效果.方法:在实验室模拟和现场两种情况下对设备的空气消毒效果进行相关试验.结果:在实验室模拟试验条件下,基于高压脉冲电场杀菌技术的新型空气消毒净化设备对人工模拟产生的粘质沙雷氏菌、白色葡萄球菌和白色念珠菌气溶胶的平均杀灭率分别为98.62%、98.65%和97.93%;在口岸现场试验条件下,设备对自然菌气溶胶的平均杀灭率为90.58%.结论:基于高压脉冲电场杀菌技术的新型空气消毒净化设备在规定的使用条件下,对空气微生物气溶胶具有良好的杀灭效果,是一种值得推广新型空气消毒净化设备.

  9. Visible-Light-Responsive Catalysts Using Quantum Dot-Modified TiO2 for Air and Water Purification (United States)

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


    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

  10. Control Measures and Experience of Air Purification Management in PIVAS of Our Hospital%我院静脉药物配置中心的空气净化管理控制措施与体会

    Institute of Scientific and Technical Information of China (English)

    邱菲; 林彩珍


    OBJECTIVE: To introduce the control measures of air purification management in clean area of PIVAS in our hospital , and to ensure the safety of injection. METHODS: The control measures of air purification management in clean area were investigated in respect of equipment, personnel and operational procedure, etc. RESULTS & CONCLUSIONS: Equipment control is conducted by maintaining pressure difference of clean area at different levels, maintaining and changing filter screen. Personnel management is conducted by pre-operational preparation and matters needing attention. Operational procedure control is carried out by maintaining "openwindows", paying attention to cutting length of ampoule, disinfection and site-clearing during standardization of drug disposing and dispensing. Above control measures can ensure purification degree of air in clean area effectively.%目的:介绍我院静脉药物配置中心洁净区内空气净化管理的控制措施,保证输液的安全.方法:从设备、人员、操作过程等方面探讨洁净区空气净化的有效控制措施.结果与结论:通过维持不同级别洁净区的压力差、维护及更换过滤网进行设备控制;通过操作前准备、操作中注意事项进行人员控制;通过规范物品摆放、配药过程中保持“开放窗口”、注意安瓿的切割长度、消毒与清场进行操作过程的控制.上述控制措施可有效保证洁净区内空气洁净程度.

  11. Application Analysis of the Pharmaceutical Purification and Low Temperature Air-conditioning and Refrigeration System%医药净化低温空调制冷系统运行的应用分析

    Institute of Scientific and Technical Information of China (English)



    This paper introduces the structure and principle of purification and air-conditioning system, and analyzes the cooling and defrosting modes from aspects of technique application and energy saving. Defrosting is the key link of low-temperature purification air-conditioning system. The system mentioned in this paper adopted double air-conditioning boxes. Each box is equipped with separate refrigeration system and is able to cool and defrost alternately, thus to meet the demand of manufacturing technique to the environment.%本文简述了净化制冷空调系统的基本构成与制冷原理.对低温表冷器的供冷与化霜方式,从技术应用和节能方面进行了分析.低温净化空调的制冷系统关键环节是要解决好化霜,通过采用双空调箱,分别各自设有独立的制冷系统,交替制冷或化霜,不问断送风,能解决生产工艺对环境的特殊要求.

  12. 空气净化在桶装饮用水企业的应用及存在的问题%Air purification application and existing problems in bottled drinking water enterprises

    Institute of Scientific and Technical Information of China (English)

    梁炜; 葛锡泳


    本文主要对桶装饮用水企业的空气净化的应用、验收及存在问题进行探讨,对车间悬浮粒子浓度进行检测、分析,为有关研究提供借鉴.%This paper explored the air purification application, acceptance and other existing problems in water enterprises, detection and analysis the suspended particle suspended particles in workshops, and provide basis for the further study.

  13. Polonium purification

    Energy Technology Data Exchange (ETDEWEB)

    Baker, J.D.


    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.

  14. Electrostatic Precipitator Technique in the Purification Process of Central Air-conditioning Systems%静电除尘技术在中央空调系统净化改造中的应用

    Institute of Scientific and Technical Information of China (English)



      结合中央空调净化系统的发展和静电除尘器的优点,通过分析目前中央空调系统中存在的问题和现有空调净化方式的不足,说明静电除尘净化方式可以解决目前空调系统中造成的室内空气污染及洁净室空调运行成本高等问题,能够使人们享受到更加洁净健康舒适的室内环境,使真正意义上的洁净空调系统得到推广。%The problems existed in central air-conditioning systems are analyzed, as well as the disadvantages of the present air-condi-tioning systems purifying methods. It also expounded the current development status of central air-conditioning systems and the advantages of the electrostatic precipitators. The analysis proved that the electrostatic dust purification method can resolve the indoor air pollution problems and the high operation cost of the air-conditioning systems in clean room effectively. The method will supply a better indoor environment which is more healthy and comfortable. This work will promote the popularization of the real clean air-conditioning systems.

  15. 浅谈手术室空气净化与消毒的方法及注意事项%Air Purification and Disinfection Methods and Precautions in the Operating Room

    Institute of Scientific and Technical Information of China (English)

    谭金煜; 尹世辉; 杜丽; 杨晶雪; 张馨心


    Important nosocomial infection control department operating room,operating room use certain clean air measures to make the operating room reaches a certain concentration of bacteria and clean air,prevention of nosocomial infection is very important. Air purification and disinfection in the use of physical methods of indoor air sterilization,sterilization,reliable effect,no residual harmful substances,no impact on the environment,to maintain sustainable effects. Chemical disinfection fast,effective and reliable,saving,usualy after the implementation of serious infection or the use of special surgical infection,in order to achieve the purpose of terminal disinfection. Work in the operating room to do air purification and disinfection work to eliminate planktonic bacteria in the air,resulting in reduction of postoperative infection.%手术室为控制院内感染的重要部门,手术室采用一定的空气洁净措施,使手术室达到一定的细菌浓度和空气洁净,预防院内感染十分重要。对空气净化与消毒中采用物理方法对室内空气进行除菌、杀菌,其效果可靠,不残留有害物质,对环境无影响,作用效果可持续保持。采用化学消毒作用迅速、效果可靠、节省,通常在施行严重感染或特殊感染手术后采用,以达到终末消毒的目的。工作中做好手术室空气净化与消毒工作,消除浮游于空气中的细菌,以减少由此引起的术后感染的发生。

  16. Logic control of molecular sieve purification system of 65000m3· h-1 air separation plant%65000m3·h-1空分设备分子筛纯化系统逻辑控制

    Institute of Scientific and Technical Information of China (English)



    The structure and technical process of molecular sieve purification system of 65000m3/ an air separation plant of Hebi coal and electeicity 600 ktpa methanol project are briefed, automatic valve closing / opening logical control of molecular sieve purification system, automatic / manual operation sequence control program,implementation of the sequence control program and optimized reform of the sequence control configuration program of the molecular sieve absorber in accordance with site operation conditions are described.%简介鹤壁煤电股份有限公司化工分公司空分厂65000m3·h-1空分设备分子筛纯化系统结构和工艺流程,介绍分子筛纯化系统阀门自动开关控制逻辑、顺控程序自动/手动运行、顺控程序执行过程,以及根据现场生产运行实际情况,对分子筛吸附器顺控组态程序进行的优化改进.

  17. Study on efficacy of air purification sterilizer in central sterile supply department%消毒供应中心使用空气净化消毒器的效果研究

    Institute of Scientific and Technical Information of China (English)

    于凤玲; 黄俊云; 王华


    OBJECTIVE To study the efficacy of air purification sterilizer applied in various regions of the central sterile supply department, to explore related sterilization performance of air purification sterilizer and to promote the improvement of controllable methods. METHODS Under the normal room temperature and humidity, three methods were employed. The first method:laboratory disinfection, the second method: the on-site air disinfection assay under people absence circumstance, the third way: on-site disinfection assay under people attendance circumstance. RESULTS Laboratory disinfection: the killing rate of Staphylococcus albus in the aerosol was more than 99. 94%. The on-site air disinfection assay under people absence circumstance: the average elimination rate of natural bacteria ranged from 93. 68% to 96. 00% in each area. The on-site disinfection assay under people attendance circumstance: static disinfection group could not continue to keep air quality but the dynamic disinfection group could make the number of bacteria keep in a normal low level in each area. CONCLUSION Under the condition of each area of the central sterile supply department that remains clean, using multi-functional air purification sterilizer to disinfect persistently can not only reduce the cost of the hospital operation but also ensure the effectiveness of air disinfection and effectively prevent the hospital infections.%目的 对消毒供应中心各个区域使用空气净化消毒器效果进行研究,探讨空气净化消毒器杀菌相关性能,并促进其改良可控的方式方法.方法 在常温常湿状态下采用3种方法分别进行试验,第1种实验室消毒试验,第2种无人情况下现场空气消毒试验,第3种在有人情况下现场消毒试验.结果 在实验室消毒试验,对气雾中白色葡萄球菌杀灭率>99.94%;无人现场空气消毒试验在各个区域平均消除率在93.68%~96.00%;在有人的情况下现场消毒试验,静态消

  18. 10种亚热带绿化树种净化大气能力初步研究%Preliminary Study on Air Purification of 10 Greening Tree Species

    Institute of Scientific and Technical Information of China (English)

    宋绪忠; 杨华; 邹景泉; 余家中; 潘忠民; 叶华琳; 姚刚


    通过对香樟(Cinnamonum campora)、广玉兰(Magnolia grandiflora)、银杏(Ginkgo biloba)、朴树(Celtis sinensis)、乌桕(Sapium sebiferum)、桂花(Osmanthus fragrans)、马银花(Rhododendron ovatum)、含笑(Michelia figo)、杜鹃(Rhododendron spp.)、三角枫(Acer buergerianum)10种亚热带绿化树种对大气中的粉尘、N、S、Cl 4种有害物质的吸收净化能力的初步测定,结果表明:单位面积滞尘量最高的树种是朴树,氮吸收最高的树种是乌桕,硫吸收最高的树种是银杏,氯吸收最高的树种是杜鹃;乔木树种的全氮含量、全硫含量、单位面积滞尘量都比灌木树种的含量高,但是全氯含量比灌木树种的含量低;落叶树种的各净化指标平均值都比常绿树种的高.%Determinations were conducted on air purification capability of ten greening tree species in Hangzhou. The result demonstrated that Celtis sinensis had the strongest capacity of dust retention, Sapium sebiferum had the best effect of absorption of N, and Ginkgo biloba of S, Rhododendron ssp of Cl. TN, TS, unit area dust retention of arbor species was larger than that of shrub species, except TCL. The air purification cabilities of deciduous trees were higher than that of evergreen trees.

  19. Experimental study on energy performance of clean air heat pump

    DEFF Research Database (Denmark)

    Fang, Lei; Nie, Jinzhe; Olesen, Bjarne W.


    An innovative clean air heat pump (CAHP) was designed and developed based on the air purification capacity of regenerative silica gel rotor. The clean air heat pump integrated air purification, dehumidification and cooling in one unit. A prototype of the clean air heat pump was developed...

  20. Analysis and treatment of trouble of molecular sieve purification system of 21000 m^3/h air separation plant%21000m^3/h空分设备分子筛纯化系统故障分析及处理

    Institute of Scientific and Technical Information of China (English)

    胥波; 闫伟东; 孔繁魁; 沈荣; 田现德


    In the air separation plant with molecular sieve adsorption and purification process, the work condition of molecular sieve purification system restricts the safe and stable run of the entire air separation system. For the troubles frequently occurring in molecular sieve purification system, such as mechanical trouble of switching over valve, valve action-generated program problem, and program-interlocked control of molecular sieve purification system, the judgment of the trouble causes and treatment measures are detailed.%分子筛吸附净化流程空分设备中,分子筛纯化系统的运行工况制约了整个空分系统的安全稳定运行。针对分子筛纯化系统经常出现的切换阀机械故障、阀门动作导致的程序问题以及分子筛纯化系统程序联锁控制等问题,详细介绍了故障原因判断和处理措施。

  1. Influence of Epipremnum aureum to Indoor Air Purification Ability%室内黄金葛绿萝植物对甲醛吸收能力的影响

    Institute of Scientific and Technical Information of China (English)



    Aldehyde are major indoor air pollutants. In the indoor landscape design, to find effective purify indoor air plant is a hotspot of research in recent years. Studies show that epipremnum aureum plant can carry on the effective absorption of formaldehyde in indoor air. But little E,aureum on other quantitative research to formaldehyde purification ability. Based on this, this paper conducted a E,aureum other quantitative experiments of formaldehyde purification ability. The results showed: (1) the E,aureum plant to formaldehyde has excellent absorption capacity;(2) compared to the control group, with the increase of concentration of formaldehyde in air, E,aureum plant chlorophyll content increased before they are lower;(3) in the case of low formaldehyde concentration in the air, plants of POD, SOD and CAT of these three enzymes activity has a significant change, and under the condition of the formaldehyde concentration is higher, the activity of these three enzymes changes significantly eased. The experimental results show that the E,aureum plant is a kind of to formaldehyde absorption capacity is strong, strong tolerance of plants, can be used for the landscape design of the building.%甲醛是室内主要的空气污染物。在室内景观设计中,寻找能够高效净化室内空气的植物是近些年来研究的热点。相关研究表明,黄金葛绿萝能够对室内空气中的甲醛进行有效吸收。但是,鲜有针对黄金葛绿萝对甲醛净化能力的定量研究。基于此,本文进行了一次黄金葛绿萝对甲醛净化能力的定量实验。结果显示:(1)黄金葛绿萝对甲醛有着优异的吸收能力;(2)与对照组相比,随着空气中甲醛浓度的增加,黄金葛绿萝的叶绿素含量先升高后降低;(3)在空气中甲醛浓度较低的情况下,植物体内的POD、SOD和CAT这三种酶的活性都有着显著的变化,而在甲醛浓度较高的情况下,这三种酶的活性变化

  2. 纳米二氧化钛光催化技术消毒和净化空气的应用研究%Application of nano-sized TiO2 photocatalysis to air purification and sterilization

    Institute of Scientific and Technical Information of China (English)

    李秉杰; 周雪媚; 钟照华; 杨德慧; 武帅钦; 李伯森; 孟浩; 姜思朋; 刘国军; 赵月辉; 崔洪波


    Objective To develop and evaluate the efficiency of air purification and sterilization instrument based on nano-sized TiO2 photocatalytic technique.Methods The nano-sized TiO2 photocatalytic air purification and sterilization instrument was designed and a sample had been prepared.The sterilization efficiencies for E.coli and Klebsiella by the nano-sized TiO2 photocatalytic instrument and ultraviolet (UV) were measured in closed labs.The on-site efficiency of the instrument was evaluated, too.Results The nano-sized TiO2 photocatalytic air purification and sterilization instrument was composed of five units: rough filter,nano-sized TiO2 photocatalytic unit,activated carbon fiber filter,negative ion generator,and programmed control unit.The E.coli killing rates by the nano-sized TiO2 photocatalytic instrument were 76.0%,81.8%,77.5%,and 80.7% at 30,60,90,and 120 minutes,respectively.There was no significant difference between the E.coli killing rates of the instrument and UV (P>0.05),except the 120 minutes timepeint.The Klebsiella killing rates by the instrument were 78.4% ,79.5% ,67.3% ,and 58.5 % at 30,60,90,and 120 minutes,respectively.The Klebsiella killing efficiencies of the instrument at 30 and 60 minutes were better than that of UV (P<0.01).There was no significant difference between the KlebsieUa killing efficiencies of the instrument and UV (P>0.05).Conclusion The air sterilization efficiency of the nano-sized TiO2 photocatalytic instrument should be equivalent or better as compared with the UV.This instrument might be used for the air purification and sterilization of the public locations.%目的 研制纳米二氧化钛(TiO2)光催化空气净化消毒器,并测试其空气消毒净化效果.方法 设计和制作纳米TiO2光催化空气净化消毒器样机.在封闭实验室将大肠埃希菌、克雷伯菌制成气雾,比较紫外线和纳米TiO2光催化空气净化消毒器消毒后残余细菌总数.在大型公共场所测试纳米TiO2光催

  3. Purification process for vertically aligned carbon nanofibers (United States)

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


    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.

  4. 可再生纳米复合材料净化网在中央空调系统中的应用探讨%The Applied Discussion of Renewable Nanocomposites Purification Device in the Central Air Conditioning System

    Institute of Scientific and Technical Information of China (English)

    宋宝龙∗; 李振海


      The TiO2-activated carbon composite materials with a visible regeneration performancewere prepared, and the development of an air cleaning facility with simple structure, good adsorption performance and low loss according to the adsorption and photocatalytic decomposition of decoupling functions. After measuring resistance of the purification equipment,this paper presented the problems and solutions in the central air conditioning system. Through the experiment and the calculation,this paper deduced the estimates formula of adsorption saturation time, which had important reference value.%  在制备出具有可见光再生性能的纳米 TiO2-活性炭复合材料后,本文根据吸附与光催化分解解耦的原则探讨研制结构简单、具有良好吸附性能、低压损的纳米活性炭空气净化装置。通过实验对净化网的阻力特性进行了探讨,提出了其在中央空调系统中的应用时的问题和解决方法,并根据实验、理论分析,推导出复合材料吸附饱和时间的概算公式,为此复合材料的实际应用提供了重要参考

  5. Air purification equipment combining a filter coated by silver nanoparticles with a nano-TiO2 photocatalyst for use in hospitals (United States)

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


    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.

  6. 盆栽植物对室内甲醛空气污染的净化研究进展%Research Advance in Purification of Formaldehyde-polluted Indoor Air by Potted Plants

    Institute of Scientific and Technical Information of China (English)

    何勤勤; 周俊辉


    Formaldehyde ( FDH) is a main indoor air pollutant , and it can cause serious hazards to human ’ s physical and mental health.Therefore, it is one of today’s hot research subjects that the air pollutants from construction and decoration materials can be absorbed and removed by potted plants .Many researches showed that the indoor FDH concentration could be reduced effec -tively by many potted plants .The purification of FHD maybe included several aspects , such as assimilation by stems or leaves of potted plants , transformation and metabolism by plant cells , and degradation by the rhizospheric microorganisms .There maybe three ways for potted plants to react with FDH pollution:the first one had high absorption but weak resistance to FDH damage , showing obvious hurt external morphology;the second one had weak absorption but strong resistance to FDH damage , revealing normal exter-nal morphology through taking avoidance strategy to protect itself;the third one showed the strongest absorption and transforming a-bility to FDH with more or less hurt responses .The purification mechanism of formaldehyde -polluted indoor air by potted plants still needs for further researches .%甲醛是室内主要的空气污染物,严重影响了人们的身心健康,寻找净化空气污染的高效盆栽植物成为近年来研究的热点。许多研究表明:盆栽植物都能有效地降低室内甲醛的浓度,对甲醛的净化作用可能有通过盆栽植物的茎叶表面吸收、植物细胞转化代谢、根际微生物吸收降解等几个方面。植物对甲醛净化可能存在3种途径或机制:第1种是对甲醛吸收能力强,但抗性弱,外部形态伤害明显;第2种是植物单位干物质吸收甲醛量较少,但采取保护自己的规避策略,保持外部形态的完整;第3种是吸收并转化,这类植物单位干物质甲醛吸收量高,同时外部形态表现基本正常或正常。对盆栽植物净化甲醛空气

  7. 从分子筛纯化系统的设计及操作谈空分设备节能%Approach to energy-saving for air separation plant from the design and operation of molecular sieve purification system

    Institute of Scientific and Technical Information of China (English)



    The energy-saving for molecular sieve purification system of air separation plant is analyzed from the process design of molecular sieve purification system, the design and selection of equipment, the engineering design and its operation and maintenance, and%从分子筛纯化系统的流程设计、设备的设计与选型、工程设计及其操作、维护等方面,分析空分设备分子筛纯化系统的节能问题,提出了对节能措施的一些思考和建议。

  8. 净化空气功能性内墙涂料的甲醛分解%Formaldehyde decomposition of air purification functional interior wall paint

    Institute of Scientific and Technical Information of China (English)

    王晓强; 张剑平; 朱惟德; 施利毅


    A novel nano-TiO2-xNx composite was used as photocatalyst and added to the interior wall paint. The average diameter of nano-TiO2-xNx was about 20 nm. The majority crystal component of the sample was anatase and its optical absorption edge was shifted from 387 nm to 520 nm significantly. Nano-composite paint containing different dosage of nano-TiO2-xNx was investigated to study the properties of formaldehyde decomposition in the air. Testing results show that the formaldehyde decomposition ratio of that nano-paint can almost reach above 80%, especially for that of the paint containing 3% (w/w) nano-TiO2-xNx, which exceeded 90%. The primary investigation on the reaction kinetics of photocatalytic formaldehyde decomposition indicated that the experiment data well fit the model of first-order reaction kinetics.

  9. Immobilization of polymeric g-C3N4 on structured ceramic foam for efficient visible light photocatalytic air purification with real indoor illumination. (United States)

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


    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.

  10. 航天器用空气净化涂层性能研究%Properties of air purification coating for spacecraft

    Institute of Scientific and Technical Information of China (English)

    王磊; 贾宏; 马重芳


    The white nano-titania coating were prepared by sol-gel method. The particle size of nano-titania was range between 10 and 20nm by the analysis of XRD and TEM. In order to testify the fact that the TiO2 coating could be used to purify air within spacecraft sealed-cabin, the nano-titania coating photocatalytic oxidation experiments were carried out. The experimental results indicate that nano-titania coating can degrade the air contaminants such as formaldehyde, sulfur dioxide and nitrogen dioxide, at the same time, which can kill the bacteria and virus such as Escherichia coli and Klebsiella pneumoniae.%采用溶胶-凝胶法制备了白色的纳米TiO2涂层。通过X射线衍射谱和透射电子显微镜的分析,表明TiO2粒径分布在10~20nm之间。为了验证纳米TiO2涂层对航天器密封舱内空气的净化作用,对TiO2涂层进行了实验研究,实验结果表明纳米TiO2涂层对甲醛、二氧化硫和二氧化氮污染气体有很好的净化效果。对大肠杆菌和肺炎克雷伯氏菌有很好的杀灭作用。

  11. The Borexino purification system (United States)

    Benziger, Jay


    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.

  12. 植物净化空气中汞污染的研究%Study on Purification of Air Mercury Pollution by Plants

    Institute of Scientific and Technical Information of China (English)

    蒋蓉芳; 周德灏; 戴修道


    对上海市常见易生长的22种植物进行了现场采样测试,结果发现,瓜子黄杨、广玉兰、海桐、蚊母、墨西哥落叶杉及棕榈对汞蒸气具有很强的吸收富集能力及抗毒性能.然后采用富集能力最强的瓜子黄杨进行一系列试验,结果显示,汞浓度随接触瓜子黄杨时间的延长而降低,而瓜子黄杨叶片的汞含量随时间的延长而增加。根据吸汞实验,计算得瓜子黄杨叶面积的吸气速率为0.133m3/h·m2。%Through investigation on 22 specie of common plants in Shanghai, it was found that Littleleaf Box,Southern Magnolia, Tobira Pittosporum, Pacemose Distylium, Mexican Cypress and Fortune Windmillpalm have great ability to absorb and enrich mercury vapour and anti-toxicity. The following experiment on Littleleaf Box which has the greatest ability of enrichment showed that concentration of mercury in the leaves of Littleleaf Box increased while the concentration of mercury vapour in indoor air decreased, and according to the absorbing experiment, the absorbing rate reached 0.133m3/h·m2.

  13. 空分设备分子筛纯化系统出口空气中二氧化碳含量超标分析与处理%Analysis and treatment of exceedance of carbon dioxide content in outlet air of molecular sieve purification system of

    Institute of Scientific and Technical Information of China (English)



    分子筛纯化系统出口空气中二氧化碳含量超标是影响空分设备稳定运行的主要因素之一。文章从分子筛纯化系统加工气体质量,设计制造,安装操作以及分子筛本身性能4方面,综合分析了导致二氧化碳含量超标的根本原因和处理措施。%The exceedance of carbon dioxide content in outlet air of molecular sieve purification system in one of main factors impairing the stable run of air separation plant. Here, the essential causes for the said exceedance of carbon dioxide content are compreh

  14. Functionalized Organosilicate Sorbents for Air Purification (United States)


    synthesized for reactive capture of targets. ADC-10 focused on incorporation of carbonyls for reactive removal of ammonia . CAR-40 focused on...16 Fig. 12 Ammonia breakthrough for E50 sorbents...23 Fig. 21 Ammonia breakthrough for the Cu DIX materials

  15. Indoor Air Purification by Potted Plants

    DEFF Research Database (Denmark)

    Dela Cruz, Majbrit

    Volatile organic compounds (VOC) are ubiquitous in the indoor environment and can affect human health negatively. Potted plants are a potential green technology solution for removal of VOCs. This PhD project aimed at reviewing current literature on VOC removal by potted plants, developing a dynam...... community structure was, however, not the same for two consecutive experiments indicating that several bacteria can degrade VOCs...

  16. Methods for air cleaning and protection of building occupants from airborne pathogens

    DEFF Research Database (Denmark)

    Bolashikov, Zhecho Dimitrov; Melikov, Arsen Krikor


    germicidal irradiation (UVGI), photocatalytic oxidation (PCO), plasmacluster ions and other technologies for air disinfection and purification from pathogens are analyzed with respect to currently used air distribution principles. The importance of indoor air characteristics, such as temperature, relative...

  17. Electron beam silicon purification

    Energy Technology Data Exchange (ETDEWEB)

    Kravtsov, Anatoly [SIA ' ' KEPP EU' ' , Riga (Latvia); Kravtsov, Alexey [' ' KEPP-service' ' Ltd., Moscow (Russian Federation)


    Purification of heavily doped electronic grade silicon by evaporation of N-type impurities with electron beam heating was investigated in process with a batch weight up to 50 kilos. Effective temperature of the melt, an indicative parameter suitable for purification process characterization was calculated and appeared to be stable for different load weight processes. Purified material was successfully approbated in standard CZ processes of three different companies. Each company used its standard process and obtained CZ monocrystals applicable for photovoltaic application. These facts enable process to be successfully scaled up to commercial volumes (150-300 kg) and yield solar grade silicon. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Water Purification Product (United States)


    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.

  19. Running Cost Analysis of Evaporative Cooling Energy-saving and Purification Air-conditioning in Supermarket of Xi'an%蒸发冷却式节能净化空调机组应用于西安某商场的经济性分析

    Institute of Scientific and Technical Information of China (English)

    宋祥龙; 黄翔; 薛运


    以中等湿度地区西安为例,对蒸发冷却式节能净化机组在商场的适用性进行分析,得出室内参数按扩展空调舒适区设计时,机组全年内均可满足空调制冷要求。与传统机械制冷空调进行对比,蒸发冷却式节能净化空调机组COP为7.9,是机械制冷的3倍,全年运行费用为17099.3元,仅为机械制冷的21.5%,适合于中等湿度地区商场的应用,节能经济。%As Xi'an an example at moderate humidity area, the evaporative cooling type energy saving analysis the applicability of the purification unit at the mall, it is concluded that when the indoor comfort zone and air conditioning design parameters according to the extension, in all the year round all can meet the requirements of air conditioning refrigeration unit. Compared with traditional mechanical refrigeration and air conditioning, evaporative cooling type energy saving to purify the air conditioning unit COP is 7.9, is three times as many mechanical refrigeration, annual operating cost is 17099.3 yuan, only 21.5%of the mechanical refrigeration, suitable for medium humidity region market application, saving energy economy.

  20. Experimental evaluation on energy performance of innovative clean air heat pump for indoor environment control in summer and winter seasons

    DEFF Research Database (Denmark)

    Nie, Jinzhe; Fang, Lei; Olesen, Bjarne W.


    Based on the air purification capacity of regenerative silica gel rotor, an innovative clean air heat pump (CAHP) was designed, developed and investigated through experimental studies. The CAHP integrated air purification, dehumidification and heating/cooling in one unit. A prototype of the CAHP...

  1. Nanomechanical Water Purification Device Project (United States)

    National Aeronautics and Space Administration — Seldon Laboratories, LLC, proposes a lightweight, low-pressure water purification device that harnesses the unique properties of carbon nanotubes and will operate...

  2. Blood purification and hemo- perfusion

    Institute of Scientific and Technical Information of China (English)


    The method of blood purification is a new overlapping frontierdiscipline which develops quickly in recent years. It helps overcoming many serious and complicated diseases, even including some incurable illnesses.

  3. Theoretical preconditions and technical substantiation for mechanical compressed air drying method application on the railway transport

    Directory of Open Access Journals (Sweden)



    Full Text Available The article is related to the compressed air purification for the rolling stock problems. The mechanical method is described as a potential way of the compressed air cooling and purificating. The temperature field at the heat conducting surface engineer function equation is given in the article as well.

  4. [Biocenotic dynamics of liquid sewage in the process of its biological purification at aeration stations]. (United States)

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


    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.

  5. Study on the Purification and Tolerance Ability of Bonsai Aloe and Snake Plant to Formaldehyde in Indoor Air%盆栽芦荟和虎皮兰对室内空气甲醛净化及耐受能力的研究

    Institute of Scientific and Technical Information of China (English)

    郭铭伟; 龚萍; 陶荣琴; 殷姿; 梁维君


    目的 研究及比较盆栽芦荟和虎皮兰对室内空气甲醛的净化及耐受能力. 方法 选择芦荟、虎皮兰两种常见、易护理且经济的盆栽植物进行三个方面的实验,即植物吸收甲醛能力的判断、不同植物吸收甲醛能力大小的比较、植物对甲醛耐受能力的研究.测得实验前后甲醛的变化量来反映植物对甲醛的净化效果,通过观察实验组植物叶片是否出现斑点、叶片枯萎、叶片坏死情况来反映绿色植物对甲醛的耐受性. 结果 实验组的甲醛浓度比对照组的甲醛浓度明显降低(P<0.01),且虎皮兰组甲醛浓度低于芦荟组(P<0.05);实验组叶片斑点增加、叶尖变黄、叶片变黄、叶片枯死等发生情况均高于对照组(P<0.05),且对虎皮兰的损伤大于芦荟(P<0.05). 结论 芦荟和虎皮兰均能净化室内空气污染物甲醛;芦荟和虎皮兰净化甲醛的能力有差异,虎皮兰比芦荟净化甲醛的能力强;甲醛对盆栽绿色植物有损伤,虎皮兰比芦荟的耐受性低.%Objective To study and compare the purification and tolerance ability of Bonsai Aloe and Snake Plant to formaldehyde in indoor air. Methods Bonsai Aloe and Snake Plant were studied and compared on their abilities to absorb and toi-erate formaldehyde in indoor air. Their purification effects were studied by detecting the formaldehyde in indoor air before and after the plants were placed in the room, with a room without plant set as the control. Their tolerance ability to formaldehyde was determined by observing the changes of the leaves, such as appearing of spots, blight, and necrosis. Results The formaldehyde concentrations in the indoor air of the experimental groups after plants placement were significantly lower than that of the control group (P<0.01), and the concentration in the Snake Plant group was statistically lower than that in the Bonsai Aloe group (P<0. 05). More spotted leaves, yellow leaves and necrotic leaves

  6. Water Purification Systems (United States)


    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.

  7. Rapid purification of recombinant histones.

    Directory of Open Access Journals (Sweden)

    Henrike Klinker

    Full Text Available 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.

  8. Purification of Water by Aquatic Plants


    Morimitsu, Katsuhito; Kawahigashi, Tatsuo


    [Abstract] Water quality purification of many water systems including those occurring in rivers depends to a great degree on water quality purification activities of aquatic plants and microbes. This paper presents a discussion of results, based on laboratory experiments, of purification by aquatic plants.


    Directory of Open Access Journals (Sweden)

    Azam Khodashenas Pelko


    Full Text Available The Jainism emphasizes three major teachings about the purification of the soul (jiva, Ahimsa, Aparigrapha and anekantwad. Jainism, The focus of this religion has been purification of the soul by means of right conduct, right faith and right knowledge. The ultimate goal of Hinduism is Moksha or liberation (total freedom. In Hinduism, purification of the soul is a goal that one must work to attain. The Buddhism is the science of pursuing the aim of making the human mind perfect, and of purifying the human soul. The knowledge of purifying of the soul and softening of the hearts is as essential for human. They having the correct motivations means purifying our souls from hypocrisy, caprice, and heedlessness. The primary goal of Taoism may be described as the mystical intuition of the Tao, which is the way, the undivided unity, and the ultimate Reality. According to the Christianity access to truth cannot be conceived without purity of the soul


    Directory of Open Access Journals (Sweden)

    Yu. P. Sedlukho


    Full Text Available The paper considers problems and features of biochemical removal of hydrogen sulfide from ground water. The analysis of existing methods for purification of ground water from hydrogen sulfide has been given in the paper. The paper has established shortcomings of physical and chemical purification of ground water. While using aeration methods for removal of hydrogen sulfide formation of colloidal sulfur that gives muddiness and opalescence to water occurs due to partial chemical air oxidation. In addition to this violation of sulfide-carbonate equilibrium taking place in the process of aeration due to desorption of H2S and CO2, often leads to clogging of degasifier nozzles with formed CaCO3 that causes serious operational problems. Chemical methods require relatively large flow of complex reagent facilities, storage facilities and transportation costs.In terms of hydrogen sulfide ground water purification the greatest interest is given to the biochemical method. Factors deterring widespread application of the biochemical method is its insufficient previous investigation and necessity to execute special research in order to determine optimal process parameters while purifying groundwater of a particular water supply source. Biochemical methods for oxidation of sulfur compounds are based on natural biological processes that ensure natural sulfur cycle. S. Vinogradsky has established a two-stage mechanism for oxidation of hydrogen sulfide with sulfur bacteria (Beggiatoa. The first stage presupposes oxidation of hydrogen sulphide to elemental sulfur which is accumulating in the cytoplasm in the form of globules. During the second stage sulfur bacteria begin to oxidize intracellular sulfur to sulfuric acid due to shortage of hydrogen sulfide.The paper provides the results of technological tests of large-scale pilot plants for biochemical purification of groundwater from hydrogen sulfide in semi-industrial conditions. Dependences of water quality

  11. Hydrogen purification by periodic adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Barg, Christian; Secchi, Argimiro R.; Trierweiler, Jorge O. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Dept. de Engenharia Quimica]. E-mail:;;


    The periodic adsorption processes have been widely used for industrial applications, mainly because it spends less energy than the usual gas separation processes, like the cryogenic distillation. The largest commercial application of periodic adsorption processes is the pressure swing adsorption (PSA) applied to hydrogen purification. Although its wide use in the chemical and petrochemical industry, there are no reports in the open literature about complete modeling studies of a complex commercial unit, with multiple adsorbents and multiple beds and several feed components. This study has as objective the modeling, optimization and dynamical analysis of an industrial PSA unit for hydrogen purification. (author)

  12. Purification and concentration of alphavirus. (United States)

    Lundstrom, Kenneth


    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 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.

  13. Bioinspired Materials for Water Purification

    Directory of Open Access Journals (Sweden)

    Alfredo Gonzalez-Perez


    Full Text Available 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.

  14. Quantum entanglement purification in cavities

    CERN Document Server

    Romero, J L; Saavedra, C; Retamal, J C


    A physical implementation of an entanglement purification protocol is studied using a cavity quantum electrodynamic based proposal, where, the quantum information is stored in quantum field sates inside cavities. Also a procedure is given for quantifying the degree of entanglement between quantum fields. (Author)

  15. Purification and properties of dialkylfluorophosphatase

    NARCIS (Netherlands)

    Cohen, J.A.; Warringa, M.G.P.J.


    1. 1. Zone electrophoresis on starch columns of purified preparations of fluorophosphatase resulted in a further purification. The preparations thus obtained differed in various respects from the cruder ones so far described. 2. 2. In the course of this electrophoresis fractions were obtained, which

  16. TIO2 based photocatalytic gas purification: the effects of co-catalysts and process conditions

    NARCIS (Netherlands)

    Fraters, Bindikt Daouda


    Photocatalysis is highly promising as a technology to mitigate environmental pollution. In this thesis the focus will be on air purification by photocatalytic oxidation of volatile organic compounds (VOC’s). A major challenge in photocatalysis is the low photonic efficiency, due to high electron hol

  17. 特殊植物类群空气凤梨对大气污染物甲醛的净化%Purification of air pollutant-formaldehyde with special plant group-epiphytic Tillandsia

    Institute of Scientific and Technical Information of China (English)

    李俊霖; 李鹏; 王恒蓉; 郑桂灵


    Epiphytic Tillandsia species uptake nutrients and moistures directly from the atmosphere, so they are often used for monitoring atmospheric heavy metal pollutants and organic pollutants, but have not been applied to the study of purifying formaldehyde yet. Two species of Tillandsia, i. e. T. usneoides and T. stricta, as well as Chlorophytum malayense, were exploited to test their ability of removing formaldehyde under two different conditions, i. e. sealed glass boxes and closed laboratory. Although the morphology and physiology of these plants had some changes, no obvius damages were suffered under formaldehyde stress. After 6-8 hours of purification with three plants, two species of Tillandsia achieved similar results with Chlorophytum. However, the speed that Tillandsia purifying formaldehyde was much higher than Chlorophytum within first 2 hours, which may due to the existence of the foliar hydrophilic trichomes on the leave surface of Tillandsia. The above results suggested that Tillandsia could purify formaldehyde more rapidly and efficiently than Chlorophytum, and it could be applied to remove indoor formaldehyde pollutant.%空气凤梨是一类生长在空气中、不需要土壤、生长所需的水分和营养可以全部来自空气的特殊植物.它们常被用来指示与修复大气重金属污染物和有机污染物,但尚未应用于甲醛净化研究.为了探讨空气凤梨对甲醛的净化效果,我们以2种空气凤梨为实验材料,吊兰为对照材料,通过密封箱内甲醛熏蒸及在封闭的实际环境中进行了实验.结果表明,松萝铁兰、硬叶空凤和吊兰3种植物在甲醛胁迫下,外部形态和生理指标有一定的变化,但未受到明显的伤害.更重要的是,3种植物对甲醛均有相当强的净化作用.6~8h后,2种空气凤梨对甲醛的净化可达到与吊兰相近的效果.而在2h内,空气凤梨净化甲醛的速度远远大于吊兰,这可能是与空气凤梨叶片表面覆盖有亲水性

  18. Membrane adsorbers as purification tools for monoclonal antibody purification. (United States)

    Boi, Cristiana


    Downstream purification processes for monoclonal antibody production typically involve multiple steps; some of them are conventionally performed by bead-based column chromatography. Affinity chromatography with Protein A is the most selective method for protein purification and is conventionally used for the initial capturing step to facilitate rapid volume reduction as well as separation of the antibody. However, conventional affinity chromatography has some limitations that are inherent with the method, it exhibits slow intraparticle diffusion and high pressure drop within the column. Membrane-based separation processes can be used in order to overcome these mass transfer limitations. The ligand is immobilized in the membrane pores and the convective flow brings the solute molecules very close to the ligand and hence minimizes the diffusional limitations associated with the beads. Nonetheless, the adoption of this technology has been slow because membrane chromatography has been limited by a lower binding capacity than that of conventional columns, even though the high flux advantages provided by membrane adsorbers would lead to higher productivity. This review considers the use of membrane adsorbers as an alternative technology for capture and polishing steps for the purification of monoclonal antibodies. Promising industrial applications as well as new trends in research will be addressed.

  19. Purification of Tetrahymena cytoskeletal proteins. (United States)

    Honts, Jerry E


    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.

  20. Comparing Russian and Finnish standards of water purification


    Maria, Pupkova


    The subject of this thesis is water purification. The first aim of this thesis is to consider different ways of water purification. The second aim is to compare Finnish and Russian standards of water purification. The third one is to show water purification methods on the pattern of Mikkeli water purification plan. Water purification methods of water intended for human consumption will be described.Combined tables will be done according to the quality requirement of drinking water of both,...

  1. Sewage Purification Business Process Management

    Directory of Open Access Journals (Sweden)

    Esad Ahmetagić


    Full Text Available This paper presents the current level of drainage and sewage purification facilities built in the Autonomous Province of Vojvodina, a territorial unit of the Republic of Serbia. It also points out the issues related to organized business management in companies involved in this business.The management of business processes in sewage purification involves a comprehensive cycle: business organizing process, issues of standard, investments, workforce, and information system design as factors in establishing an effective organization of business processes. The definition of gap existing between the current approach to organizing business activities and the need to establish an approach based on knowledge, information technologies, and effective business process management points to the necessity for organization redesign and standard definition in business process management. Sewage purification business process management in Vojvodina, the Republic of Serbia has been elaborated through theoretical presentation and a practical example realized by electronic ISO 9001:2008 system of quality management in public water utility company JKP "Vodokanal" Sombor.

  2. Purification technology of molten aluminum

    Institute of Scientific and Technical Information of China (English)

    孙宝德; 丁文江; 疏达; 周尧和


    Various purification methods were explored to eliminate the dissolved hydrogen and nonmetallic inclusions from molten aluminum alloys. A novel rotating impeller head with self-oscillation nozzles or an electromagnetic valve in the gas circuit was used to produce pulse gas currents for the rotary impeller degassing method. Water simulation results show that the size of gas bubbles can be decreased by 10%-20% as compared with the constant gas current mode. By coating ceramic filters or particles with active flux or enamels, composite filters were used to filter the scrap A356 alloy and pure aluminum. Experimental results demonstrate that better filtration efficiency and operation performance can be obtained. Based on numerical calculations, the separation efficiency of inclusions by high frequency magnetic field can be significantly improved by using a hollow cylinder-like separator or utilizing the effects of secondary flow of the melt in a square separator. A multi-stage and multi-media purification platform based on these methods was designed and applied in on-line processing of molten aluminum alloys. Mechanical properties of the processed scrap A356 alloy are greatly improved by the composite purification.

  3. Technological assumptions for biogas purification. (United States)

    Makareviciene, Violeta; Sendzikiene, Egle


    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.

  4. Synergistic effect of Brønsted acid and platinum on purification of automobile exhaust gases. (United States)

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


    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.

  5. Nano TiO2 photocatalytic materials and its applications in air purification within submarine cabins%纳米TiO2光催化材料及其在潜艇内空气净化中的应用

    Institute of Scientific and Technical Information of China (English)

    王中驰; 黎德龙; 潘春旭


    The air quality within the submarine cabin is one of the major indicators in ensuring the normal operation of submarines. As a new photocatalysis, extensive attentions has been paid to nano TiO2 due to its effective and high degradation efficiency as well as its potential applications in environmental pollution treatment. With the continuous modification and improvement in recent years, the photocatalytic perfor⁃mance of nano TiO2 has been greatly enhanced, with its practical applications being promoted and developed as well. As a result, the air quality control via nano TiO2 photocatalysis in submarine cabins has become one of the most important research subjects. In this paper, according to the analysis on the compositions of hazardous gases and their damage to submarines, an overview of the recent development and feasibility of nano TiO2 on degrading organic pollution, anti-bacteria, and deodorization is presented, and its applications in degrading Volatile Organic Compounds(VOCs) as well as in air purification multi-technology is ex⁃plored. In addition, the technical solutions regarding the immobilization and low photocatalytic efficiency problems of nano TiO2 are proposed during practical applications. In brief, this paper provides useful sug⁃gestions and guidance for further nano TiO2 application in controlling air quality within submarine cabins.%潜艇舱室内空气质量的优劣是衡量潜艇正常运行的重要指标之一。纳米TiO2作为一种新型高效无污染光催化材料,在环境污染处理中具有广泛的应用前景,一直受到国内外研究者的关注。近年来,随着纳米TiO2的不断改性,光催化性能不断提高,在实际应用中得到了推广和开发,如何有效利用纳米TiO2光催化材料控制潜艇舱室内的空气质量水平成为一个极其重要的研究和应用领域。通过对潜艇内的有害气体组成与危害进行分析,综述了近几年在纳米TiO2光催化材料制备

  6. QuestAir hydrogen separation technology

    Energy Technology Data Exchange (ETDEWEB)

    Henkel, B. [QuestAir Technologies Inc., Burnaby, British Columbia (Canada)


    QuestAir's gas purification products employ a process known as pressure swing adsorption (PSA). PSA is based on the adsorption of gases onto special materials known as adsorbents. These adsorbents remove all contaminants from an impure feed stream to produce a purified product gas. Once the adsorbents are near saturation, the impurities are purged, regenerating the adsorbents for the next PSA cycle. QuestAir's patented technology has reduced the duration of the PSA cycle by up to 10 times, allowing for a similar reduction in the size of system components such as pressure vessels, piping and structural supports. Our simple, compact and reliable technology is a significant improvement over conventional PSA hydrogen purification systems, and it also has significant advantages over other gas purification technologies such as membranes and cryogenic plants.

  7. Argon Collection And Purification For Proliferation Detection

    Energy Technology Data Exchange (ETDEWEB)

    Achey, R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hunter, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)


    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.


    DEFF Research Database (Denmark)


    Purification of fluoride contaminated magadi is studied using bone char sorption and calcium precipitation. The bone char treatment is found to be workable both in columns and in batches where the magadi is dissolved in water prior to treatment. The concentrations in the solutions were 89 g magadi...... treatment method. A procedure for purification of fluoride contaminated magadi at household level is described....

  9. Biogas Purification up to Final Product

    Directory of Open Access Journals (Sweden)

    Yu. Losiuk


    Full Text Available The paper considers main technological methods for biogas purification from impurities that permit to increase energy value of the product and decrease its corrosion activity.  While evaluating economic efficiency due to introduction of the corresponding purification technology, in addition, it is necessary to take into account an ecological factor.

  10. Boron carbide morphology changing under purification (United States)

    Rahmatullin, I. A.; Sivkov, A. A.


    Boron carbide synthesized by using coaxial magnetoplasma accelerator with graphite electrodes was purified by two different ways. XRD-investigations showed content changing and respectively powder purification. Moreover TEM-investigations demonstrated morphology changing of product under purification that was discussed in the work.

  11. A study of naturally occurring radon in Swedish water purification plants.



    Radon dissolved in drinking-water can be transferred into the indoor air and is one of the main transfer pathways for radon. At water purification plants, large quantities of water are treated and there is a risk that radon degasses from the water and enters into the indoor air. Hence, there is a risk for elevated radon levels in the indoor air at these facilities. This study aims to investigate the general impact of water treatment processes on the radon concentration in water and its transf...

  12. The importance of the ammonia purification process in ammonia-water absorption systems

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Seara, Jose [Area de Maquinas y Motores Termicos, Escuela Tecnica Superior de Ingenieros Industriales, Universidad de Vigo, Campus Lagoas-Marcosende No. 9, 36200 Vigo (Spain)]. E-mail:; Sieres, Jaime [Area de Maquinas y Motores Termicos, Escuela Tecnica Superior de Ingenieros Industriales, Universidad de Vigo, Campus Lagoas-Marcosende No. 9, 36200 Vigo (Spain)


    Practical experience in working with ammonia-water absorption systems shows that the ammonia purification process is a crucial issue in order to obtain an efficient and reliable system. In this paper, the detrimental effects of the residual water content in the vapour refrigerant are described and quantified based on the system design variables that determine the effectiveness of the purification process. The study has been performed considering a single stage system with a distillation column with complete condensation. The ammonia purification effectiveness of the column is analysed in terms of the efficiencies in the stripping and rectifying sections and the reflux ratio. By varying the efficiencies from 0 to 1, systems with neither the rectifying nor stripping section, with either the rectifying or stripping section, or with both sections can be considered. The impact of the ammonia purification process on the absorption system performance is studied based on the column efficiencies and reflux ratio; and its effects on refrigerant concentration, system COP, system pressures and main system mass flow rates and concentrations are analysed. When the highest efficiency rectifying sections are used a combination of generation temperature and reflux ratio which leads to optimum COP values is found. The analysis covers different operating conditions with air and water cooled systems from refrigeration to air conditioning applications by changing the evaporation temperature. The importance of rectification in each kind of application is evaluated.

  13. 纳米TiO_2/功能性空气滤料在净化空气方面的研究现状与展望%The Status Quo and Development of Nano TiO_2 Functional Air Filter Materials in Air Purification

    Institute of Scientific and Technical Information of China (English)

    于振强; 强天伟; 黄翔


    Presents the definition of nano TiO2 functional air filter materials,expounds the research and development of unctional air filter materials and the achievements in the nano photocatalysis technology at home and abroad,overviews research status of the nano photocatalysis technology by Xi’an Polytechnic University,laid the foundation for the indoor air cleaning and the development of indoor air purifiers,and point out the existing problems and research direction.%介绍了纳米TiO2/功能性空气滤料的定义,阐述了功能性空气滤料的研究与发展历程和国内外在纳米光催化技术方面取得的成就,综述了西安工程大学在纳米光催化技术方面的研究现状,为室内空气净化的研究及室内空气净化器的开发奠定了基础,并指出了存在的问题和今后发展方向。

  14. Visible Light Responsive Catalyst for Air Water Purification Project (United States)

    Wheeler, Raymond M.


    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.

  15. Carbon Nanotube Electron Sources for Air Purification Project (United States)

    National Aeronautics and Space Administration — Pollution of the environment is a world wide concern and is the subject of broadly based R&D into means of prevention and remediation. The innovation proposed...

  16. Dispersion and Purification of Single-Wall Carbon Nanotubes Using Carboxymethylcellulose (United States)

    Takahashi, Teruo; Tsunoda, Katsunori; Yajima, Hirofumi; Ishii, Tadahiro


    We have developed a novel method for the purification of single-wall carbon nanotubes (SWNTs) that involves annealing in air and dispersing the SWNTs in an aqueous solution of carboxymethylcellulose (CMC). The purity of the resulting SWNTs was evaluated by analytical techniques such as electron microscopy, Raman spectroscopy, and thermogravimetric analysis (TGA). As a result, it was revealed that CMC functioned as an effective dispersion reagent in the exfoliation of the SWNT bundles and thereby, SWNTs with appreciably high quality were prepared.

  17. Reverse osmosis water purification system (United States)

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


    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.

  18. Liquid membrane purification of biogas

    Energy Technology Data Exchange (ETDEWEB)

    Majumdar, S.; Guha, A.K.; Lee, Y.T.; Papadopoulos, T.; Khare, S. (Stevens Inst. of Tech., Hoboken, NJ (United States). Dept. of Chemistry and Chemical Engineering)


    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.

  19. Extracorporeal blood purification in burns: a review. (United States)

    Linden, Katharina; Stewart, Ian J; Kreyer, Stefan F X; Scaravilli, Vittorio; Cannon, Jeremy W; Cancio, Leopoldo C; Batchinsky, Andriy I; Chung, Kevin K


    A prolonged and fulminant inflammatory state, with high levels of pro- and anti-inflammatory mediators, is seen after extensive thermal injury. Blood purification techniques including plasma exchange, continuous venovenous hemofiltration, and adsorbing membranes have the potential to modulate this response, thereby improving outcomes. This article describes the scientific rationale behind blood purification in burns and offers a review of literature regarding its potential application in this patient cohort.

  20. EUV tools: hydrogen gas purification and recovery strategies (United States)

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


    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.

  1. Unified Model of Purification Units in Hydrogen Networks

    Institute of Scientific and Technical Information of China (English)

    吴思东; 王彧斐; 冯霄


    Purification processes are widely used in hydrogen networks of refineries to increase hydrogen reuse. In refineries, hydrogen purification techniques include hydrocarbon, hydrogen sulfide and CO removal units. In addi-tion, light hydrocarbon recovery from the hydrogen source streams can also result in hydrogen purification. In order to simplify the superstructure and mathematical model of hydrogen network integration, the models of different pu-rification processes are unified in this paper, including mass balance and the expressions for hydrogen recovery and impurity removal ratios, which are given for all the purification units in refineries. Based on the proposed unified model, a superstructure of hydrogen networks with purification processes is constructed.

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

    Institute of Scientific and Technical Information of China (English)

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


    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 fer-rous sulfate solution without and with purification pretreatment. Calcium hydroxide was added to the solution of ferrous sulfate as a pre-cipitator. 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 pu-rification 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.

  3. Effect of purification pretreatment on the recovery of magnetite from waste ferrous sulfate (United States)

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


    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.

  4. Air Pollution (United States)

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

  5. Screening in humid air plasmas (United States)

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


    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.

  6. Cyclodextrin purification with hollow fibers

    Energy Technology Data Exchange (ETDEWEB)

    Berthod, A. (Univ. de Lyon 1, Villeubranne Cedex (France)); Jin, Heng Liang,; Armstrong, D.W. (Univ. of Missouri, Rolla (USA))


    Cyclodextrins are cyclic 1-4 linked oligomers of {alpha}-D-glucopyranose prepared from starch hydrolysis through enzymatic reactions. Mixtures of the three main cyclodextrins (CD), {alpha}-, {beta}-, and {gamma}-CDs, are always produced. A possible facile purification process is proposed. Permeation through hollow fibers made of a perfluorinated ionomer membrane. Nafion type, is shown to be an effective way to separate {alpha}-CD from {beta}- and {gamma}-CD. {Alpha}-CD with 95% purity was obtained after permeation through a Nafion hollow fiber of an equimolar 0.02 M solution of the three CDs. The fiber had a 56 cm{sup 2}/cm{sup 3} surface area per volume ratio. Kinetic studies and continuous extraction experiments with a 2-m coiled fiber showed that it is possible to obtain a 11.5 g {alpha}-CD solution with 92.4% purity or a 0.6 g {alpha}-CD solution with 97.2% purity, depending on the flow rate. The transport of CDs through the membrane could be due to moving water pools inside the ionomer. The small {alpha}-CD fits easily in such pools when the large {beta}- and {gamma}-CDs are excluded by steric hindrance. Temperature raises increased the permeation rates while decreasing the selectivity. The process could be scaled-up associating hollow fibers in bundle.

  7. Ionic behavior of treated water at a water purification plant


    Yanagida, Kazumi; Kawahigashi, Tatsuo


    [Abstract] Water at each processing stage in a water purification plant was extracted and analyzed to investigate changes of water quality. Investigations of water at each processing stage at the water purification plant are discussed herein.

  8. Novel peptide ligand with high binding capacity for antibody purification

    DEFF Research Database (Denmark)

    Lund, L. N.; Gustavsson, P. E.; Michael, R.


    Small synthetic ligands for protein purification have become increasingly interesting with the growing need for cheap chromatographic materials for protein purification and especially for the purification of monoclonal antibodies (mAbs). Today, Protein A-based chromatographic resins are the most ......-aggregated IgG, indicating that the ligand could be used both as a primary purification step of IgG as well as a subsequent polishing step. (C) 2012 Elsevier B.V. All rights reserved....

  9. 21 CFR 876.5665 - Water purification system for hemodialysis. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 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...

  10. Purification of Carbon Nanotubes: Alternative Methods (United States)

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


    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.

  11. Reconsidering Rapid Qubit Purification by Feedback

    CERN Document Server

    Wiseman, H M


    This paper reconsiders the properties of a scheme for the rapid purification of the quantum state of a qubit, proposed recently in Jacobs 2003 Phys. Rev. A67 030301(R). The qubit starts in a completely mixed state, and information is obtained by a continuous measurement. Jacobs' rapid purification protocol uses Hamiltonian feedback control to maximise the average purity of the qubit for a given time, with a factor of two increase in the purification rate over the no-feedback protocol. However, by re-examining the latter approach, we show that it mininises the average time taken for a qubit to reach a given purity. In fact, the average time taken for the no-feedback protocol beats that for Jacobs' protocol by a factor of two. We discuss how this is compatible with Jacobs' result, and the usefulness of the different approaches.

  12. Overview of the purification of recombinant proteins. (United States)

    Wingfield, Paul T


    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.

  13. Purification and Characterization of Tryptophan Hydroxylase

    DEFF Research Database (Denmark)

    Haahr, Lærke Tvedebrink

    This thesis deals with the purification and characterization of the iron-containing enzyme tryptophan hydroxylase (TPH). TPH exists in two isoforms, called TPH1 and TPH2. Each isoform consists of threestructural distinct domains: the regulatory, the catalytic and the tetramerization domain. TPH...... of this project was to developpurification methods for full-length TPH1 and TPH2 as well as to characterize purified TPH variants. A successful purification method for full-length human TPH1 (hTPH1) was developed, which resulted in pure, active and stable protein. The method includes affinity-purification using....... The crystallization procedure for the catalytic domain of gallus gallus TPH1 (cgTPH1) was optimized to faster crystal growth by addition of tryptophan and incubation at room temperature. Crystals without imidazole in the crystallization conditions could be obtained. The solved structures were however of poor quality...

  14. Soft-Bake Purification of SWCNTs Produced by Pulsed Laser Vaporization (United States)

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


    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.

  15. Purification of contaminated groundwater by membrane technology

    Energy Technology Data Exchange (ETDEWEB)

    Youn, In Soo; Chung, Chin Ki; Kim, Byoung Gon [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)


    The objective of this study is to apply the membrane separation technology to the purification of contaminated ground water in Korea. Under this scope, the purification was aimed to the drinking water level. The scale of the membrane system was chosen to a small filtration plant for local clean water supplies and/or heavy purifiers for buildings and public uses. The actual conditions of ground water contamination in Korea was surveyed to determine the major components to remove under the drinking water requirements. To set up a hybrid process with membrane methods, conventional purification methods were also investigated for the comparison purpose. The research results are summarized as follows : 1) Contamination of the groundwater in Korea has been found to be widespread across the country. The major contaminant were nitrate, bacteria, and organic chlorides. Some solvents and heavy metals are also supposed to exist in the ground water of industrial complexes, cities, and abandoned mines. 2) The purification methods currently used in public filtration plants appear not to be enough for new contaminants from recent industrial expanding. The advanced purification technologies generally adopted for this problem have been found to be unsuitable due to their very complicated design and operation, and lack of confidence in the purification performance. 3) The reverse osmosis tested with FilmTec FT30 membrane was found to remove nitrate ions in water with over 90 % efficiency. 4) The suitable membrane process for the contaminated groundwater in Korea has been found to be the treatments composed of activated carbon, microfiltration, reverse osmosis or ultrafiltration, and disinfection. The activated carbon treatment could be omitted for the water of low organic contaminants. The microfiltration and the reverse osmosis treatments stand for the conventional methods of filtration plants and the advanced methods for hardly removable components, respectively. It is recommended

  16. Air stripping. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)



    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 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

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

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  18. Intein-mediated purification system: mechanism and applications

    Institute of Scientific and Technical Information of China (English)

    Sarra setrerrahmane; Shuhua Tan


    The incorporation of self-cleaving protein elements into a variety of fusion-based purification systems; has been an important development in the area of recombinant protein purification. The self-cleaving capability of these tags has recently been combined with additional purification tags to generate novel and convenient protein purification methods. This review elucidates the properties of intein, the mechanism of the intein-based protein splicing and the progress of intein-based protein purification procedures, and recent advances in the applications of intein.

  19. Enterovirus 71 Virus Propagation and Purification


    Kristin L Shingler; Organtini, Lindsey J.; Hafenstein, Susan


    Since its discovery in 1969, enterovirus 71 (EV71) has emerged as a serious worldwide health threat. This member of the picornavirus family causes hand, foot, and mouth disease, and also has the capacity to invade the central nervous system to cause severe disease and death. This is the propagation and purification procedure to produce infectious virion.

  20. Expression and Purification of Sperm Whale Myoglobin (United States)

    Miller, Stephen; Indivero, Virginia; Burkhard, Caroline


    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…

  1. Purification of His-Tagged Proteins. (United States)

    Spriestersbach, Anne; Kubicek, Jan; Schäfer, Frank; Block, Helena; Maertens, Barbara


    Ni-NTA affinity purification of His-tagged proteins is a bind-wash-elute procedure that can be performed under native or denaturing conditions. Here, protocols for purification of His-tagged proteins under native, as well as under denaturing conditions, are given. The choice whether to purify the target protein under native or denaturing conditions depends on protein location and solubility, the accessibility of the His tag, and the desired downstream application. His-tagged proteins can be purified by a single-step affinity chromatography, namely immobilized metal ion affinity chromatography (IMAC), which is commercially available in different kinds of formats, Ni-NTA matrices being the most widely used. The provided protocols describe protein purification in the batch binding mode and apply gravity-assisted flow in disposable columns; this procedure is simple to conduct and extremely robust. IMAC purification can equally be performed in prepacked columns using FPLC or other liquid chromatography instrumentation, or using magnetic bead-based methods (Block et al., 2009).

  2. Purification of functionalized DNA origami nanostructures. (United States)

    Shaw, Alan; Benson, Erik; Högberg, Björn


    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.

  3. Investigation of efficiency of air cleaning from acetone using a segmental construction biofilter

    Directory of Open Access Journals (Sweden)

    Denas Bacevičius


    Full Text Available Volatile organic compounds, e. g. acetone, have a direct impact on climate change, decrease of ozone in the air, and on the growth of greenhouse effect. One of the most popular air purifying methods from VOC is a biological air cleaning. Experimental investigations were conducted to determine the efficiency of the new structure of biofilter with polypropylene plates segments. During the investigations the efficiency of segmental construction biofilter of air purification at different initial concentrations of pollutants was determined. Different concentrations of pollutants were estimated during the acetone dilution with water. During the tests the efficiency of biofilter air purification from acetone vapor and its change under different concentrations of vapors was set. Based on test results, the maximum efficiency of biofilter air purification was up to 93%. Studies have shown that increasing the allowable pollutant concentration, the efficiency of air purification unit decreases. Increasing the concentration of supplied acetone vapor into the biofilter from 232 to 701 mg/m3, cleaning efficiency decreased from 92.8 to 82.3%. Since microorganisms fail to oxidize organic compounds, the filter works better at lower initial concentrations of pollutants.

  4. Mathematical Modeling of Self- Purification Capacity of Surface Currents. Study Case: Portoviejo River, Ecuador

    Directory of Open Access Journals (Sweden)

    Luis Santiago Quiroz Fernández


    Full Text Available It is proposed a phenomenological model to describe the behavior of oxygen concentration with respect to distance from wastewater loading into the river. It taken into account processes associated with con-taminants biodegradation and oxygen transfer through interface air-water. The model was used to study contamination of Portoviejo River, Manabí, Ecuador. Experimental results were adjusted to an approx-imate solution of the obtained no-linear equations system, and it was possible to estimate parameters which are related with the capacity of self-purification of two river zones. 

  5. Purification of crude biodiesel using dry washing and membrane technologies

    Directory of Open Access Journals (Sweden)

    I.M. Atadashi


    Full Text Available Purification of crude biodiesel is mandatory for the fuel to meet the strict international standard specifications for biodiesel. Therefore, this paper carefully analyzed recently published literatures which deal with the purification of biodiesel. As such, dry washing technologies and the most recent membrane biodiesel purification process have been thoroughly examined. Although purification of biodiesel using dry washing process involving magnesol and ion exchange resins provides high-quality biodiesel fuel, considerable amount of spent absorbents is recorded, besides the skeletal knowledge on its operating process. Further, recent findings have shown that biodiesel purification using membrane technique could offer high-quality biodiesel fuel with less wastewater discharges. Thus, both researchers and industries are expected to benefit from the development of membrane technique in purifying crude biodiesel. As well biodiesel purification via membranes has been shown to be environmentally friendly. For these reasons, it is important to explore and exploit membrane technology to purify crude biodiesel.

  6. Purification of Carbon Nanotubes by Proton Irradiation (United States)

    Kim, Euikwoun; Lee, Jeonggil; Lee, Younman; Jeon, Jaekyun; Kim, Jae-Yong; Kim, Jeongha; Shin, Kwanwoo; Youn, Sang-Pil; Kim, Kyeryung


    Carbon nanotubes (CNTs) exhibit variety of superior physical properties including well-defined nanodimensional structure, high electrical and thermal conductivity, and good mechanical stability against external irradiations. Further, a large specific surface area per unit weight suggests that carbon nanotubes could be excellent candidates for gas storage, purification, and separation. However, the practical application of CNTs is limited mainly due to the metallic impurities that were used as a catalyst during the fabrication process. Here, we irradiated CNTs by using high energy proton beams (35.7 MeV at the Bragg Peak). Interestingly, metallic impurities such as Fe, Ni, Co and chunk of amorphous carbon that were attached on the surface of CNTs were completely removed after the irradiation. The mechanism of such the purification process is not understood. The possible speculation will be demonstrated combined with the changes of physical properties including the appearance of the magnetism after the irradiation.

  7. Nanotechnology for water treatment and purification

    CERN Document Server

    Apblett, Allen


    This book describes the latest progress in the application of nanotechnology for water treatment and purification. Leaders in the field present both the fundamental science and a comprehensive overview of the diverse range of tools and technologies that have been developed in this critical area. Expert chapters present the unique physicochemical and surface properties of nanoparticles and the advantages that these provide for engineering applications that ensure a supply of safe drinking water for our growing population. Application areas include generating fresh water from seawater, preventing contamination of the environment, and creating effective and efficient methods for remediation of polluted waters. The chapter authors are leading world-wide experts in the field with either academic or industrial experience, ensuring that this comprehensive volume presents the state-of-the-art in the integration of nanotechnology with water treatment and purification. Covers both wastewater and drinking water treatmen...

  8. Purification of Logic-Qubit Entanglement. (United States)

    Zhou, Lan; Sheng, Yu-Bo


    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.

  9. Purification of nanoparticles by hollow fiber diafiltration (United States)

    Veeken, J.


    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.

  10. Affinity Purification of Protein Complexes Using TAP Tags (United States)

    Gerace, Erica; Moazed, Danesh


    This protocol is used for the isolation and analysis of protein complexes using the tandem affinity purification (TAP) tag system. The protocol describes the purification of a protein fused to a TAP tag comprised of two protein A domains and the calmodulin binding peptide separated by a TEV cleavage site. This is a powerful technique for rapid purification of protein complexes and the analysis of their stoichiometric composition, posttranslational modifications, structure, and functional activities. PMID:26096502

  11. Surface processes during purification of InP quantum dots



    Recently, a new simple and fast method for the synthesis of InP quantum dots by using phosphine as phosphorous precursor and myristic acid as surface stabilizer was reported. Purification after synthesis is necessary to obtain samples with good optical properties. Two methods of purification were compared and the surface processes which occur during purification were studied. Traditional precipitation with acetone is accompanied by a small increase in photoluminescence. It occurs that during ...

  12. Purification of tubulin from porcine brain. (United States)

    Gell, Christopher; Friel, Claire T; Borgonovo, Barbara; Drechsel, David N; Hyman, Anthony A; Howard, Jonathon


    Microtubules, polymers of the heterodimeric protein αβ-tubulin, give shape to cells and are the tracks for vesicle transport and chromosome segregation. In vitro assays to study microtubule functions and their regulation by microtubule-associated proteins require the availability of purified αβ-tubulin. In this chapter, we describe the process of purification of heterodimeric αβ-tubulin from porcine brain.

  13. Conductive diamond electrodes for water purification

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Martínez-Huitle


    Full Text Available Nowadays, synthetic diamond has been studied for its application in wastewater treatment, electroanalysis, organic synthesis and sensor areas; however, its use in the water disinfection/purification is its most relevant application. The new electrochemistry applications of diamond electrodes open new perspectives for an easy, effective, and chemical free water treatment. This article highlights and summarizes the results of a selection of papers dealing with electrochemical disinfection using synthetic diamond films.

  14. Rotating Reverse-Osmosis for Water Purification (United States)

    Lueptow, RIchard M.


    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.

  15. Purification of GST-Tagged Proteins. (United States)

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


    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.

  16. Simplified purification method for Clostridium difficiletoxin A

    Institute of Scientific and Technical Information of China (English)

    Si-Wu Fu; Jing Xue; Ya-Li Zhang; Dian-Yuan Zhou


    AIM: To establish the purification method for Clostridiumdifficile ( 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)2SO4and acid precipitation at pH 5.5, followed by ion-exchange chromatography on DEAE-Toyopearl.RESULTS: Purified toxin A exhibited only one band on nativepolyacrylamide gel electrophoresis (native-PAGE) andOuchterlony 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 1×106 MLD/mL (i.p.mice). The cytotoxictiter was 107 CU/mg. The haemagglutinate activity was ata 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.

  17. Efficient entanglement purification for doubly entangled photon state

    Institute of Scientific and Technical Information of China (English)


    In this paper,we present an efficient purification scheme that improves the efficiency of entanglement purification of the recently proposed entanglement purification scheme for doubly entangled photon states (Phys.Rev.A,2008,77:042315).This modified scheme contains the bit-flip error correction where all the photon pairs can be kept while all the bit-flip errors are corrected and the entanglement purification of phase-flip errors where a wavelength conversion process is used.This scheme has the advantage of high efficiency and a much lower minimum fidelity of the original state.It works under existing technology.

  18. Compressorless Gas Storage and Regenerative Hydrogen Purification Project (United States)

    National Aeronautics and Space Administration — Microwave regenerative sorption media gas storage/delivery techniques are proposed to address both compressed gas management and hydrogen purification requirements...

  19. Purification of cytochrome P450 BM-3 as a monooxygenase. (United States)

    Jun, Huang; Lehe, Mei; Qing, Sheng; Dongqiang, Lin; Shanjing, Yao


    After investigating two anion-exchange resins, the purification factor and activity yields of P450 BM-3 were higher with Resource Q than with DEAE-Sepharose FF. Screening of HIC media showed that Source 15ISO was the most suitable for purification of P450 BM-3. An effective isolation and purification procedure of P450 BM-3 was developed and included three steps: 35%-70% saturation (NH(4))(2)SO(4) precipitation, Source 15ISO hydrophobic interaction chromatograph and Sephacryl S-200 gel filtration chromatography. Using this protocol, the purification factor and P450 BM-3 activity recovery was 13.5 and 13.7%, respectively.

  20. Efficient entanglement purification for doubly entangled photon state

    Institute of Scientific and Technical Information of China (English)

    WANG Chuan; SHENG YuBo; LI XiHan; DENG FuGuo; ZHANG Wei; LONG GuiLu


    In this paper,we present an efficient purification scheme that improves the efficiency of entanglement purification of the recently proposed entanglement purification scheme for doubly entangled photon states(Phys.Rev.A,2008,77:042315).This modified scheme contains the bit-flip error correction where all the photon pairs can be kept while all the bit-flip errors are corrected and the entanglement purification of phase-flip errors where a wavelength conversion process is used.This scheme has the advantage of high efficiency and a much lower minimum fidelity of the original state.It works under existing technology.

  1. Purification of scrap aluminum foil and aluminum melt covering and protecting & atomic purification theory

    Institute of Scientific and Technical Information of China (English)

    倪红军; 孙宝德; 刘满平; 丁文江


    A new flux, JDN-I, including rare earth compounds, for purification of the scraps of 99.99% aluminum foil was introduced. The experimental results indicate that its function of degassing and deoxidizing is excellent. The hydrogen content of the scrap aluminum foil melt purified by JDN-I flux decreases greatly from 4.5 mL/kg to 1.2 mL/kg at 720 ℃. The tensile strength of the samples refined with JDN-I flux increases by 19.2% and the elongation increases by 38.3% in comparison with those without flux. The purification mechanism of JDN-I was discussed and a theory of covering, protecting & atomic purification was also put forward.

  2. Dense Medium Plasma Water Purification Reactor (DMP WaPR) Project (United States)

    National Aeronautics and Space Administration — The Dense Medium Plasma Water Purification Reactor offers significant improvements over existing water purification technologies used in Advanced Life Support...

  3. EB technology for the purification of flue gases

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Takuji [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment


    Sulfur oxides and nitrogen oxides in flue gas from coal-combustion boilers in power plants, dioxins in flue gas from municipal waste incineration facilities and toxic volatile organic compounds (VOCs) in off-gas from painting or cleaning factories are among air pollutants for which emission is regulated by a law in Japan. Electron beam is the effective and easy controllable radiation source for treatment of these flue gases. This report describes outline of the results so far obtained at JAERI on electron beam treatment of flue gas. The removal performance higher than 90% at 10 kGy for flue gas containing 800 ppm SOx and 225 ppm NOx were achieved and being applied to real-scale power plants in Poland and China with expectation of cost reduction of 20% compared to conventional plants. Decomposition of dioxins in flue gas from solid waste incinerators is another project. Using an accelerator of 300 keV and 40 mA for treatment of real incineration gas at 200degC, we obtain 90% decomposition of dioxins at 15 kGy irradiation. Expansion of these flue gas purification technologies combined with low-energy electron accelerators is expected. (S. Ohno)

  4. 建筑室内植物对空气净化能力的研究——2010年上海世博会"沪上·生态家"植物筛选%Study on Indoor Air Purification Ability of Plants-Plants Screening for Shanghai Eco-home of the World Expo 2010 China Shanghai

    Institute of Scientific and Technical Information of China (English)



    2010年世博会以"城市,让生活更美好"为主题,"城市最佳实践区"的首次设立是本次世博会的创举和亮点之一,"沪上·生态家"是唯一代表上海参展2010年上海世博会的实物案例项目.为达到环境宜居和室内环境达标率100%的目标,同时满足(GB/T 50378-2006)三星级绿色建筑标准,"沪上·生态家"团队以目前市场上较为常用的室内观赏植物为测试对象,建立了测试方法以研究其叶片部分在模拟甲醛超标环境中的甲醛净化效果,为"沪上·生态家"的植物筛选提供试验依据.研究发现不同植物对甲醛的吸收能力不同,净化效果存在差异:在24 h内试验的50种植物中,迷迭香单位叶面积净化甲醛量最多,黄金葛绿萝净化率最大;同时植物会使植物测试舱内的湿负荷增加.在测试结果的基础上,综合景观效益,选取了部分植物作为上海世博会"沪上·生态家"的室内观赏植物.%The theme of the World Expo 2010 China Shanghai was better city, better life, and the establishment of urban best practices area (UBPA) was one of the original and bright spot works.In UBPA, Shanghai Eco-home was the only selected project represented Shanghai to join the Expo 2010.In order to satisfy the Evaluation Standard for Green Building (GB/T 50378-2006) and achieve the livable environment, the market commonly used indoor ornamental plants were taken as the research objects, the purification effects of plants' leaves in the simulated excessive formaldehyde environment were studied.The measured results indicated that different plants had different absorption capacities of formaldehyde, also for the purification abilities.During the test period of 24 h and for all the 50 kinds of plants,the unit leaf area of rosemary had the largest ability to purify the formaldehyde and the scindapsus aureum had the largest purification rate.Meanwhile, the moisture load in the test chamber was increased due to the plants.Based on

  5. Surface processes during purification of InP quantum dots

    Directory of Open Access Journals (Sweden)

    Natalia Mordvinova


    Full Text Available Recently, a new simple and fast method for the synthesis of InP quantum dots by using phosphine as phosphorous precursor and myristic acid as surface stabilizer was reported. Purification after synthesis is necessary to obtain samples with good optical properties. Two methods of purification were compared and the surface processes which occur during purification were studied. Traditional precipitation with acetone is accompanied by a small increase in photoluminescence. It occurs that during the purification the hydrolysis of the indium precursor takes place, which leads to a better surface passivation. The electrophoretic purification technique does not increase luminescence efficiency but yields very pure quantum dots in only a few minutes. Additionally, the formation of In(OH3 during the low temperature synthesis was explained. Purification of quantum dots is a very significant part of postsynthetical treatment that determines the properties of the material. But this subject is not sufficiently discussed in the literature. The paper is devoted to the processes that occur at the surface of quantum dots during purification. A new method of purification, electrophoresis, is investigated and described in particular.

  6. The Induced Self-Purification of Creeks and Rivers

    CERN Document Server

    Mikhailovskii, V


    The clean-up of several Creeks and Rivers by induction of a self-purification process was provided. The process took place at all the sites studied with the up to 100% resulted removal of polluting agents depending on the site and nature of the contaminant. The self-purification mechanism could be used for drinking and technical water preparation.

  7. Surface processes during purification of InP quantum dots. (United States)

    Mordvinova, Natalia; Emelin, Pavel; Vinokurov, Alexander; Dorofeev, Sergey; Abakumov, Artem; Kuznetsova, Tatiana


    Recently, a new simple and fast method for the synthesis of InP quantum dots by using phosphine as phosphorous precursor and myristic acid as surface stabilizer was reported. Purification after synthesis is necessary to obtain samples with good optical properties. Two methods of purification were compared and the surface processes which occur during purification were studied. Traditional precipitation with acetone is accompanied by a small increase in photoluminescence. It occurs that during the purification the hydrolysis of the indium precursor takes place, which leads to a better surface passivation. The electrophoretic purification technique does not increase luminescence efficiency but yields very pure quantum dots in only a few minutes. Additionally, the formation of In(OH)3 during the low temperature synthesis was explained. Purification of quantum dots is a very significant part of postsynthetical treatment that determines the properties of the material. But this subject is not sufficiently discussed in the literature. The paper is devoted to the processes that occur at the surface of quantum dots during purification. A new method of purification, electrophoresis, is investigated and described in particular.

  8. Research of the thorium purification at monazite refinement processes (United States)

    Shagalov, V. V.; Sobolev, V. I.; Turinskaya, M. V.; Malin, A. V.


    This paper is aimed to the research of the thorium purification processes at monazite refinement processes. We have investigated different solution containing thorium with different mix of rare-earth elements. It was found that the application of cation resin is well- recommended if we want to reach the highest yields of thorium purification process.

  9. An Adaptable Investigative Graduate Laboratory Course for Teaching Protein Purification (United States)

    Carroll, Christopher W.; Keller, Lani C.


    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…

  10. A scintillator purification system for the Borexino solar neutrino detector (United States)

    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.


    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.

  11. One-step purification of E. coli elongation factor Tu

    DEFF Research Database (Denmark)

    Knudsen, Charlotte Rohde; Clark, Brian F. C.; Degn, B


    The tuf A gene, encoding the E. coli elongation factor Tu, was cloned in the pGEX gene fusion system. Upon expression EF-Tu is fused to glutathione-S-transferase serving as a purification handle with affinity for glutathione immobilised on agarose. This allows purification of EF-Tu in a one...

  12. Purification and fluorescent labeling of the human serotonin transporter

    DEFF Research Database (Denmark)

    Rasmussen, Søren G F; Gether, Ulrik


    To establish a purification procedure for the human serotonin transporter (hSERT) we expressed in Sf9 insect cells an epitope-tagged version of the transporter containing a FLAG epitope at the N-terminus and a polyhistidine tail at the C-terminus (FLAG-hSERT-12H). For purification, the transporter...

  13. Air Cleaning Technologies (United States)


    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

  14. Biotechnology Protein Expression and Purification Facility (United States)


    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.

  15. Purification of a single photon nonlinearity

    CERN Document Server

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


    We show that the lifetime-reduced fidelity of a semiconductor quantum dot-cavity single photon nonlinearity can be restored by polarization pre- and postselection. This is realized with a polarization degenerate microcavity in the weak coupling regime, where an output polarizer enables quantum interference of the two orthogonally polarized transmission amplitudes. This allows us to transform incident coherent light into a stream of strongly correlated photons with a second-order correlation function of g2(0)~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.

  16. Efficient entanglement purification in quantum repeaters

    Institute of Scientific and Technical Information of China (English)

    Sheng Yu-Bo; Zhou Lan; Cheng Wei-Wen; Gong Long-Yan; Zhao Sheng-Mei; Zheng Bao-Yu


    We present an efficient entanglement purification protocol (EPP) with controlled-not (CNOT) gates and linear optics.With the CNOT gates,our EPP can reach a higher fidelity than the conventional one.Moreover,it does not require the fidelity of the initial mixed state to satisfy · · 1· 2.If the initial state is not entangled,it still can be purified.With the linear optics,this protocol can get pure maximally entangled pairs with some probabilities.Meanwhile,it can be used to purify the entanglement between the atomic ensembles in distant locations.This protocol may be useful in long-distance quantum communication.

  17. Purification of Nanoparticles by Size and Shape (United States)

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


    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    DeNardo, S.J.


    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.

  19. Biopharmaceuticals from microorganisms: from production to purification

    Directory of Open Access Journals (Sweden)

    Angela Faustino Jozala

    Full Text Available ABSTRACT 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.

  20. [Isolation and purification of virus damaging sunflower]. (United States)

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


    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.

  1. Purification and characterization of double-wall carbon nanotubes synthesized by catalytic chemical vapor deposition on mesoporous silica (United States)

    Ramesh, P.; Okazaki, T.; Sugai, T.; Kimura, J.; Kishi, N.; Sato, K.; Ozeki, Y.; Shinohara, H.


    Double-wall carbon nanotubes (DWNTs) have been selectively synthesized by catalytic chemical vapor deposition of alcohol over Fe/Co loaded mesoporous silica. The as-grown carbon nanotubes are purified using a multi-step process involving heat treatment in air followed by alkali and acid treatments. The nanotubes are characterized as-grown and after each step of the purification stage by thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. It is observed that most of the mesoporous silica and metal particles have been removed from the as-grown nanotubes by these treatments. The carbon content of the nanotube material obtained after the purification is found to be more than 90 wt%.

  2. An Innovative Reactor Technology to Improve Indoor Air Quality

    Energy Technology Data Exchange (ETDEWEB)

    Rempel, Jane [TIAX LLC., Lexington, MA (United States)


    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.

  3. Design strategies for integrated protein purification processes: challenges, progress and outlook

    NARCIS (Netherlands)

    Nfor, B.; Ahamed, T.; Dedem, G.; Wielen, van der L.; Sandt, van de E.; Eppink, M.H.M.; Ottens, M.


    The key to successful and efficient protein purification is the selection of the most appropriate purification techniques and their combination in a logical way to obtain the desired purification in the minimum number of steps. However, the rationalization of protein purification process development

  4. Generation and Purification of Atomic Entangled States

    Institute of Scientific and Technical Information of China (English)

    YANG Ming; SONG Wei; LI Yingqun; SHI Shouhua; CAO Zhuoliang


    @@ Entangled state plays a more and more important role in quantum information, so the generation of entangled state is of scientific value and practical significance.Although the experimental realization of entangled pairs of atoms and polarized photons have been reported recently, the current preparation schemes cannot meet the need of the practical application of entangled state in Quantum Communication and Quantum Computation.At the same time, resulting from the coupling between the quantum systems and its environment, decoherence of the quantum systems is unavoidable, which sets a vital obstacle on the way of the application of entanglement.There exist some entanglement generation and purification schemes, but the range of its application is relative small.So we proposed a more efficient scheme for entanglement generation and purification.The scheme is mainly based on the combination of linear optics and Cavity QED technique.The entanglement generation scheme can entangle two atoms by using MZI plus an optical cavity.Pure maximally entangled atomic states can be generated from product states or mixed states.Using a MZI, we can extract not only two-atom near-maximally entangled states but also four-atom maximally entangled states from less entangled pure or mixed states.

  5. Online Oxide Contamination Measurement and Purification Demonstration (United States)

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


    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.

  6. Biomimetic affinity purification of Candida antarctica lipase B. (United States)

    Yao, Hongyan; Zhang, Tian; Xue, Hongwei; Tang, Kexuan; Li, Rongxiu


    Candida antarctica lipase B (CalB) is one of the most widely used biocatalysts in organic synthesis. The traditional method for purification of CalB is a multi-step, high cost and low recovery procedure. Biomimetic affinity purification had high efficiency purification. We selected 298 ligand columns from a 700-member library of synthetic ligands to screen Pichia pastoris protein extract. Of the 298, three columns (named as A9-14, A9-10, and A11-33) had one-step purification effect, and A9-14 of these affinity ligands, had both high purification and recovery. The one-step recovery of CalB reached 73% and the purification reached 91% upon purification. The active groups of A9-14 were cyclohexylamine and propenylamine. Furthermore, both A9-14 and A9-10 had the same R1 active group of cyclohexylamine which might act the main binding role for CalB. The synthetic ligand A9-14 had a binding capacity of 0.4 mg/mL and had no negative effects on its hydrolytic activity. Unlike a natural affinity ligand, this synthetic ligand is highly stable to resist 1M NaOH, and thus has great potential for industrial scale production of CalB.

  7. Proteomics in extracorporeal blood purification and peritoneal dialysis. (United States)

    Thongboonkerd, Visith


    Extracorporeal blood purification and peritoneal dialysis are widely used in renal replacement therapy for patients with end-stage renal disease (ESRD) and acute kidney injury (AKI). Additionally, extracorporeal blood purification can be used also for treatment of non-renal disorders to remove endogenous or exogenous toxins from the blood circulation. Efforts have been made to characterize these toxins removed by diffusion (dialysis), convection (ultrafiltration), and/or adsorption (toxins are adsorbed onto the dialysis membrane and are thus removed) using different types of dialysis membrane. This review summarizes important findings obtained from recent proteomic studies applied to extracorporeal blood purification and peritoneal dialysis in settings of ESRD, AKI and hepatic failure.

  8. The efficiency study of different purification methods for liquid scintillator

    CERN Document Server

    Hu, Wei; Yu, Boxiang; Zhang, Xuan; Zhou, Li; Cai, Xiao; Sun, Lijun


    JUNO is an experiment aimed at detecting neutrino mass hierarchy. The innermost part of the JUNO detector is formed by 20,000 tons of liquid scintillator which should have very low level of radioactive materials, such as 238U, 232Th, and 40K. Since the radioactive level of raw LAB(the solvent of LS)cannot reach so stringent requirements of JUNO, the purification for LAB plays an extremely important role in LS production. This article studies the efficiency of several different purification methods for LS, like distillation, water extraction and Al2O3 purification.

  9. Nylon wool purification alters the activation of T cells. (United States)

    Wohler, Jillian E; Barnum, Scott R


    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.

  10. Purification and Structural Analysis of Desmoplakin. (United States)

    Choi, Hee-Jung; Weis, William I


    Desmoplakin (DP) is an obligate component of desmosomes, where it links the desmosomal cadherin/plakoglobin/plakophilin assembly to intermediate filaments. DP contains a large amino-terminal domain (DPNT) that binds to the cadherin/plakoglobin/plakophilin complex, a central coiled-coil domain that dimerizes the molecule, and a C-terminal domain (DPCT) that binds to intermediate filaments. DPNT contains a plakin domain, comprising a set of spectrin-like repeats. DPCT contains three plakin repeat domains, each formed by 4.5 repeats of a sequence motif known as a plakin repeat that bind to intermediate filaments. Here, we review purification, biochemical characterization, and structural analysis of the DPNT plakin domain and the DPCT plakin repeat domains.

  11. Purification and characterization of the Oligosaccharyl transferase

    Energy Technology Data Exchange (ETDEWEB)

    Kapoor, T.M.


    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.

  12. Purification of a single-photon nonlinearity (United States)

    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.


    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

  13. Concentration and purification of plutonium or thorium (United States)

    Hayden, John A.; Plock, Carl E.


    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.

  14. Nanocellulose-Based Materials for Water Purification

    Directory of Open Access Journals (Sweden)

    Hugo Voisin


    Full Text Available 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.

  15. Protein purification using PDZ affinity chromatography. (United States)

    Walkup, Ward G; Kennedy, Mary B


    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.

  16. Staphylococcal micrococcins. II. Isolation, purification and identification. (United States)

    Breiter, J; Metz, H; Grigo, J


    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.

  17. Purification of RNA from milk whey. (United States)

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


    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.

  18. Carbon Nanotube–Purification and Sorting Protocols

    Directory of Open Access Journals (Sweden)

    Poornendu Chaturvedi


    Full Text Available Carbon nanotubes (CNTs have shown extraordinary mechanical, thermal, electrical, and electronic properties. Electronic properties of CNT are very sensitive to its diameter and chirality, making it metallicor semiconducting, depending upon its chiral vector. The extraordinary properties of CNTs have led to demonstration of several applications but commercial realisation of these devices require consistent qualityof CNTs, and these should be  free of any impurity. For development of electronic devices, CNTs should notjust be pure but also of similar length, diameter, and electronic behaviour. Such demanding requirements need development of elaborate purification and sorting protocols. In this paper,  a brief review of the existing technologies and the research done is presented.Defence Science Journal, 2008, 58(5, pp.591-599, DOI:


    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...

  20. Materials for next-generation desalination and water purification membranes (United States)

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


    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.

  1. Composite purification technology and mechanism of recycled aluminum alloys

    Institute of Scientific and Technical Information of China (English)

    房文斌; 耿耀宏; 安阁英; 叶荣茂


    Iron-rich inclusions in aluminum alloys can be effectively removed by composite purification of sedimentation and filtration technology.The results show that the purposed method has no negative effects on aluminum alloys and obviously improve their mechanical properties.

  2. Separation and Purification of Fissiogenic Ruthenium From Irradiated Uranium

    Institute of Scientific and Technical Information of China (English)


    Ruthenium is an important fission product. Its isotopic composition may reflect the burnup or the initial uranium enrichment of nuclear fuel. So the separation and purification method of fission products of Ruthenium from irradiated uranium was studied and established.

  3. 室内植物对甲醛净化性能的研究进展%Progress of Research on the Purification of Formaldehyde by Plants

    Institute of Scientific and Technical Information of China (English)

    蔡宝珍; 金荷仙; 熊伟


    随着人们生活水平的提高,室内空气净化已成为人们普遍关心的问题,而甲醛作为室内空气污染的头号杀手,引起了人们的巨大关注.笔者简述室内甲醛污染的来源、危害以及净化甲醛的重要性.与物理吸附、化学吸收、光催化和生物降解等技术相比,植物净化甲醛技术具有自然、环保、操作简单的特点,已经成为室内甲醛净化和室内植物景观研究的热点和前沿科学之一.综述植物净化甲醛的国内外研究进展,着重从吸附净化、代谢净化及根际微生物的降解净化等3方面阐述植物净化甲醛的机理,介绍植物净化甲醛的毒理研究进展,同时指出目前研究中存在的主要问题,并进一步提出未来的研究发展方向.%Purification of indoor polluted air becomes a common concern topic along with living standards'enhancement.As the top killer of indoor polluted air, the formaldehyde pollution was of special concern.The origin of formaldehyde and its enormous pollution in indoor air were inevitable, so it was very import to purify indoor air formaldehyde.Compared with technology of physical absorption, chemical absorption, photocatalytic biodegradable, the purification of formaldehyde by plant was natural, environmental and easy operate, which became the hot topic and advanced science in the research of purification of indoor formaldehyde and houseplant landscape.The domestic and abroad research progress of aerobic granular sludge was summerized.The theory of purification of formaldehyde was the absorption by the stem and foliage, the metabolism and transformation by the plant, and the degradation by the rhizosphere microorganism.Toxicological purification of formaldehyde by indoor plants was viewed.Advantages and disadvantages in research were reported, too.Finally, the foreground of the purification of formaldehyde by indoor plants was prospected.

  4. Separation process design for isolation and purification of natural products

    DEFF Research Database (Denmark)

    Malwade, Chandrakant R.

    , thereby providing process information crucial for determining synergistic effects between different unit operations. In this work, the formulated methodology has been used to isolate and purify artemisinin, an antimalarial drug, from dried leaves of the plant Artemisia annua. A process flow sheet...... is generated consisting of maceration, flash column chromatography and crystallization unit operations for extraction, partial purification and final purification of artemisinin, respectively. PAT framework is used extensively to characterize the process streams at molecular level and the generated process...

  5. Sodium Purification Device for Production of Tantalum Powder

    Institute of Scientific and Technical Information of China (English)


    In the process of tantalum powder production it requires pure sodium to reduce potassium fluotantalate, thus the design of a sodium purification device is improved, later it is built and commissioned. The device includes sodium transportation tank, storage tank, filter, cold trap, final storage tank, metering tank, regulating valve, argon purification system, electric control panel and instrument. Industrial purity sodium is purified, the impurities in the sodium were reduced to very

  6. Economic Methods of Ginger Protease'sextraction and Purification (United States)

    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.

  7. Production, purification, and capsid stability of rhinovirus C types. (United States)

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


    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.

  8. Recommended methods for purification of solvents and tests for impurities

    CERN Document Server

    Coetzee, J F


    Recommended Methods for Purification of Solvents and Tests for Impurities is a compilation of recommended procedures for purification of solvents and tests for solvent impurities. Ten solvents are covered: acetonitrile, sulfolane, propylene carbonate, dimethyl sulfoxide, dimethylformamide, hexamethylphosphoramide, pyridine, ethylenediamine, N-methylacetamide, and N-methylpropionamide. This book is comprised of 12 chapters and opens with an introduction to general aspects of impurity effects. The rationale for the selection of solvent is explained, and the relative reactivities of solutes in di

  9. Purification of human platelet-derived growth factor

    Energy Technology Data Exchange (ETDEWEB)

    Raines, E.W.; Ross, R.


    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.

  10. New data on electron-beam purification of wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Pikaev, A.K. E-mail:


    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 {gamma}-irradiation.

  11. New data on electron-beam purification of wastewater (United States)

    Pikaev, A. K.


    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.

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


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


    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/de...

  13. Purification of human leucocyte DNA: proteinase K is not necessary. (United States)

    Douglas, A M; Georgalis, A M; Benton, L R; Canavan, K L; Atchison, B A


    A rapid nontoxic method for the purification of DNA from human leucocytes is described. Preliminary experiments which tested different methods of DNA purification indicated that digestion of proteins with proteinase K was unnecessary. This led to the development of a simple procedure involving lysis of the cells in SDS followed by extraction with 6 M NaCl. The method described overcomes the requirement for lengthy incubations in the presence of expensive proteinase K and subsequent extraction with toxic chemicals.

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

    Directory of Open Access Journals (Sweden)

    Boiko R.S.


    Full Text Available 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.

  15. Monogamy, polygamy, and other properties of entanglement of purification (United States)

    Bagchi, Shrobona; Pati, Arun Kumar


    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.

  16. Air Pollution (United States)

    ... to view this content or go to source URL . What NIEHS is Doing on Air Pollution Who ... Junction Last Reviewed: February 06, 2017 This page URL: NIEHS website: Email ...

  17. Extraction and purification of {sup 227}Ac and development of solid {sup 219}Rn source

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Quan; Qiu, Shoukang; Xiao, Detao; Zhou, Yaohui; An, Xiaogang [University of South China, Hengyang (China). Radon Key Laboratory of Hunan Province/School of Nuclear Science and Technology


    The method of {sup 227}Ac extraction and purification from high-grade uranium ore and the test results of solid {sup 219}Rn source made from {sup 227}Ac are reported in this paper. With five years of follow-up monitoring, radiochemical purity of {sup 227}Ac and the emanation power of solid {sup 219}Rn source has been checked by emanation method and γ-spectrometry, the results showed that {sup 228}Th, {sup 231}Pa and {sup 226}Ra have been effectively removed and the emanation power of {sup 219}Rn source is about 80%. The long-term test results also showed that the {sup 219}Rn emanation rate remains stable in a wide air humidity range (40% ∝ 90%). Though the {sup 219}Rn source has not been accurately calibrated yet, it has been applied in the research for delay coincidence measurement of {sup 223}Ra. (orig.)

  18. Air surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Patton, G.W.


    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).

  19. Myxoma virus: propagation, purification, quantification, and storage. (United States)

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


    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.

  20. Isolation and Purification of Biotechnological Products (United States)

    Hubbuch, Jürgen; Kula, Maria-Regina


    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.

  1. TMI-2 purification demineralizer resin study

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, J D; Osterhoudt, T R


    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 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.

  2. Neurotrophic factor - Characterization and partial purification (United States)

    Popiela, H.; Ellis, S.


    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. Purification of equine Gc-globulin

    DEFF Research Database (Denmark)

    Houen, Gunnar; Pihl, Tina Holberg; Andersen, Pia Haubro;

    Objectives With the aim of producing antibodies for an equine Group specific component (Gc)-globulin assay, the protein was purified from normal equine plasma. Methods Equine Gc-globulin was purified from healthy horse plasma using ion exchange chromatography (Q-Sepharose, CM-Sepharose) and prepa......Objectives With the aim of producing antibodies for an equine Group specific component (Gc)-globulin assay, the protein was purified from normal equine plasma. Methods Equine Gc-globulin was purified from healthy horse plasma using ion exchange chromatography (Q-Sepharose, CM......-Sepharose) and preparative PAGE. Results Equine Gc-globulin has successfully been purified from healthy horse plasma and rabbits and mice are being immunized to produce specific antibodies. Conclusions Purification of equine Gc-globulin and the production of specific antibodies will make it possible to develop an assay...... for measuring Gc-globulin in horses. Studies in rodents and humans have shown that Gc-globulin is a multifunctional acute phase plasma protein, which removes actin from the blood by binding it and facilitating its clearance from the circulation by the liver. As such, Gc-globulin prevents hyper coagulation...

  4. Entanglement purification of unknown quantum states (United States)

    Brun, Todd A.; Caves, Carlton M.; Schack, Rüdiger


    A concern has been expressed that ``the Jaynes principle can produce fake entanglement'' [R. Horodecki et al., Phys. Rev. A 59, 1799 (1999)]. In this paper we discuss the general problem of distilling maximally entangled states from N copies of a bipartite quantum system about which only partial information is known, for instance, in the form of a given expectation value. We point out that there is indeed a problem with applying the Jaynes principle of maximum entropy to more than one copy of a system, but the nature of this problem is classical and was discussed extensively by Jaynes. Under the additional assumption that the state ρ(N) of the N copies of the quantum system is exchangeable, one can write down a simple general expression for ρ(N). By measuring one or more of the subsystems, one can gain information and update the state estimate for the remaining subsystems with the quantum version of the Bayes rule. Using this rule, we show how to modify two standard entanglement purification protocols, one-way hashing and recurrence, so that they can be applied to exchangeable states. We thus give an explicit algorithm for distilling entanglement from an unknown or partially known quantum state.

  5. Characterization and purification of bacteriophages using chromatofocusing. (United States)

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


    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.

  6. Biologically Inspired Purification and Dispersion of SWCNTs (United States)

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


    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.

  7. Purification of carbon nanotubes grown by thermal CVD (United States)

    Porro, S.; Musso, S.; Vinante, M.; Vanzetti, L.; Anderle, M.; Trotta, F.; Tagliaferro, A.


    We show the results of a set of purifications on carbon nanotubes (CNT) by acid and basic treatments. CNTs were obtained by thermal decomposition of camphor at 850 °C in a CVD growth system, by means of a growth process catalyzed by iron clusters originating from the addition of ferrocene in the precursors mixture. The purification procedures involved HNO 3, H 2SO 4, HSO 3Cl and NaOH for different process temperatures. As-grown CNTs showed a consistent presence of metal catalyst (about 6 wt%), evidenced by TGA. The purification treatments led to a certain amount of opening of the CNT tips, with a consequent loss of metal catalyst encapsulated in tips. This is also confirmed by BET analysis, which showed an increase of the surface area density of CNT after the purification. FT-IR and XPS revealed the presence of carboxylic groups on the CNT surface chemically modified by the harsh environment of the purification process. Among the various treatments that have been tested, the 1:3 solution of nitric and sulphuric acid was the most effective in modifying the CNT surface and inducing the formation of functional groups.

  8. Purification of a-galactosidase from seeds of Sesbania marginata

    Directory of Open Access Journals (Sweden)

    Falco A.L.P.


    Full Text Available Alpha-galactosidase taken from a raw extract of Sesbania marginata legume seeds was purified by partitioning in aqueous two-phase systems (ATPS. Initially, galactomannan/dextran 2,000,000 systems were used for the purification, and the partition coefficients of alpha -galactosidase varied from 1.5 to 4.0. However, mass transport in these systems was poor due to the high viscosity of the employed polymers. Therefore, partitioning in polyethyleneglycol (PEG/ sodium phosphate systems and the effect of sodium chloride upon the enzyme purification and the yield of alpha -galactosidase were also investigated. The purification achieved in a single-step was 5.7 with a recovery of 144% of alpha -galactosidase, possibly due to the removal of materials which inhibited alpha -galactosidase activity before the purification. The removal of the main protein contaminants and the highest yields were achieved in PEG 4,000/ sodium phosphate + 6% NaCl system at pH 5.0. Further purification by preparative on-exchange chromatography was also developed.

  9. Efficient and inexpensive method for purification of heparin binding proteins. (United States)

    Batra, Sumit; Sahi, Nilesh; Mikulcik, Kristen; Shockley, Heather; Turner, Camille; Laux, Zachary; Badwaik, Vivek D; Conte, Eric; Rajalingam, Dakshinamurthy


    Heparin binding (HB) proteins mediate a wide range of important cellular processes, which makes this class of proteins biopharmaceutically important. Engineering HB proteins may bring many advantages, but it necessitates cost effective and efficient purification methodologies compared to currently available methods. One of the most important classes of HB proteins are fibroblast growth factors (FGFs) and their receptors (FGFRs). In this study, we report an efficient off-column purification of FGF-1 from soluble fractions and purification of the D2 domain of FGFR from insoluble inclusion bodies, using a weak Amberlite cation (IRC) exchanger. FGF-1 and the D2 domain have been expressed in Escherichia coli and purified to homogeneity using IRC resin. This approach is an alternative to conventional affinity column chromatography, which exhibits several disadvantages, including time-consuming experimental procedures for purification and regeneration and results in the expensive production of recombinant proteins. Results of the heparin binding chromatography and steady state fluorescence experiments show that the FGF-1 and the D2 are in a native conformation. The findings of this study will not only aid an in-depth investigation of this class of proteins but will also provide avenues for inexpensive and efficient purification of other important biological macromolecules.

  10. The Blood Compatibilities of Blood Purification Membranes and Other Materials Developed in Japan


    Takaya Abe; Karen Kato; Tomoaki Fujioka; Tadao Akizawa


    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 purif...

  11. Royal Danish Air Force. Air Operations Doctrine

    DEFF Research Database (Denmark)

    Nørby, Søren

    This brief examines the development of the first Danish Air Force Air Operations Doctrine, which was officially commissioned in October 1997 and remained in effect until 2010. The development of a Danish air power doctrine was heavily influenced by the work of Colonel John Warden (USAF), both...... through his book ”The Air Campaign” and his subsequent planning of the air campaign against Iraq in 1990-1991. Warden’s ideas came to Denmark and the Danish Air Force by way of Danish Air Force students attending the United States Air Force Air University in Alabama, USA. Back in Denmark, graduates from...... the Air University inspired a small number of passionate airmen, who then wrote the Danish Air Operations Doctrine. The process was supported by the Air Force Tactical Command, which found that the work dovetailed perfectly with the transformation process that the Danish Air Force was in the midst...


    Directory of Open Access Journals (Sweden)

    Irina Ramona PECINGINĂ


    Full Text Available Biological filtration systems is one of the current alternatives to remove residual volatile components of the air through biological means, without affecting the natural environment. Biofilters have a technology that uses microorganisms (bacteria to treat emissions, in a secure economic and environmental quality. Biofilters consist of porous filters, which is distributed flue gas stream

  13. Detection of protein-protein interactions using tandem affinity purification. (United States)

    Goodfellow, Ian; Bailey, Dalan


    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.

  14. Nylon Wool Purification Alters the Activation of T Cells (United States)

    Wohler, Jillian E.; Barnum, Scott R.


    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

  15. Factors influencing the purification efficiency of photosynthetic bacteria

    Institute of Scientific and Technical Information of China (English)


    One strain of photosynthetic bacteria (PSB) was isolated from substrate sludge offresh-water fishpond. Influence of the use level of PSB culture solution, illumination condition,temperature, salinity, the use level of copper sulfate and dipterex on the purification efficiency was investigated. The results showed that the optimum use level of PSB culture solution was 10 mg/L,and the purification efficiency at illumination was higher than that at black, and if the temperature was lower than 15℃, or the use level of sodium chloride, copper sulfate and dipterex were higherthan 10 000 mg/L, 0.4 mg/L and 2.0 mg/L, respectively, the purification efficiency dropped distinctly.

  16. Purification of artemisinin excerpt from Artemisia annua L

    Directory of Open Access Journals (Sweden)

    Chemat-Djenni Z.


    Full Text Available The active pharmaceutical substance artemisinin found in Artemisia annua L. remains the most effective remedy against malaria. The objective of this work is the purification of the active ingredient through a natural matrix composed of clay sandwiched by aluminum. The purification process is carried by adsorption of the extracts on sodium type and bridged clay type. The XRD characterization of this material shows an increase in the basal distance of 10 Å to 17 Å. This shows the success of the intercalation of aluminum polycation. We find a better purification of the extract when using aluminum bridged clay compared to sodium clay. The best performance of 80.64% adsorption is obtained at 40 ° C for the clay matrix bridged with aluminum complex.

  17. Purification of fluorescently labeled Saccharomyces cerevisiae Spindle Pole Bodies (United States)

    Davis, Trisha N.


    Centrosomes are components of the mitotic spindle responsible for organizing microtubules and establishing a bipolar spindle for accurate chromosome segregation. In budding yeast, Saccharomyces cerevisiae, the centrosome is called the spindle pole body, a highly organized tri-laminar structure embedded in the nuclear envelope. Here we describe a detailed protocol for the purification of fluorescently labeled spindle pole bodes from S. cerevisiae. Spindle pole bodies are purified from yeast using a TAP-tag purification followed by velocity sedimentation. This highly reproducible TAP-tag purification method improves upon previous techniques and expands the scope of in vitro characterization of yeast spindle pole bodies. The genetic flexibility of this technique allows for the study of spindle pole body mutants as well as the study of spindle pole bodies during different stages of the cell cycle. The ease and reproducibility of the technique makes it possible to study spindle pole bodies using a variety of biochemical, biophysical, and microscopic techniques. PMID:27193850

  18. Preparative Purification of Liriodendrin from Sargentodoxa cuneata by Macroporous Resin. (United States)

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


    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.

  19. Isolation of the mTOR complexes by affinity purification. (United States)

    Sarbassov, Dos D; Bulgakova, Olga; Bersimbaev, Rakhmet I; Shaiken, Tattym


    The mammalian Target Of Rapamycin (mTOR) protein is a central component of the essential and highly conserved signaling pathway that emerged as a critical effector in regulation of cell physiology. Biochemical studies defined mTOR as the protein kinase that exists at least in two distinct complexes. The first complex has been characterized as the nutrient-sensitive mTOR complex 1 that controls cell growth and cell size by regulating protein synthesis and autophagy. The second complex of mTOR has been defined as the component of growth factor signaling that functions as a major regulatory kinase of Akt/PKB. Here, we provide the detailed methods how to purify the functional complexes of mTOR by affinity purification. In the first part, we describe the purification of the distinct mTOR complexes by immunoprecipitation. Purification of the soluble mTOR complexes is explained in the second part of this chapter.

  20. Characterizationof Crude Cellulase from Trichoderma reesei and Purification of Cellulase

    Institute of Scientific and Technical Information of China (English)

    姚善泾; 关怡新; 等


    The gel filtration was carried out for purification of cellulase.The influences of chromatographic parameters on the resolution were studied to determine the optimal conditions for purification.The purified endoglucanase was obtained by gel filtration by Superdex 75 prep grade with an activity recovery of 92.8% and the purification factor 4.2.The sample volume should be below 6% of the column bed volume and the column bed height L≥12.0 cm.The optimum catalysis temperature and pH for the enzyme were 55℃and 4.5-.0 respectively.The cellulase was stable at pH ranging from 4.0 to 6.0 and temperature below 60℃.

  1. Purification and separation of durene by static melt crystallization☆

    Institute of Scientific and Technical Information of China (English)

    Shan Cong; Ying Liu; Hong Li; Xingang Li; Lvhong Zhang; Lei Wang


    The purification and separation of durene from the mixture containing durene isomers were studied. Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great differences, stat-ic melt crystallization was applied to separate and purify durene from its isomers. Crystallization experiments were carried out under various operating conditions. The effects of cooling rate, crystallization temperature, sweating temperature and sweating time on the yield and purity of crystal were investigated. Orthogonal exper-imental design method was adopted to analyze the factors that may affect the yield of durene. Under the optimal crystal ization conditions, the purity of durene could reach as high as 99.06%with the yield of 75.3%through one crystal ization process. By fitting purification data based on sweating time in isothermal operations, the purifica-tion rate coefficient was obtained.

  2. A simple method for purification of herpesvirus DNA

    DEFF Research Database (Denmark)

    Christensen, Laurids Siig; Normann, Preben


    A rapid and reliable method for purification of herpesvirus DNA from cell cultures is described. The method is based on the isolation of virus particles and/or nucleocapsids by differential centrifugation and exploits the solubilizing and denaturing capabilities of cesium trifluoroacetate during ...... isopycnic centrifugation, so that phenol/chloroform extractions can be omitted. The method was used for the purification of DNA from several members of the Alfaherpesvirinae subfamily.......A rapid and reliable method for purification of herpesvirus DNA from cell cultures is described. The method is based on the isolation of virus particles and/or nucleocapsids by differential centrifugation and exploits the solubilizing and denaturing capabilities of cesium trifluoroacetate during...

  3. The Status of KamLAND After Purification (United States)

    Grant, Christopher


    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. )

  4. Bromelain: an overview of industrial application and purification strategies. (United States)

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


    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.


    Kalmanson, G; Bronfenbrenner, J


    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

  6. Process for purification of petroleum oil fractions

    Energy Technology Data Exchange (ETDEWEB)

    Gaile, A.A.; Proskuryakov, V.A.; Semenov, L.V.; Ul' chenkova, L.M.; Volkova, N.I.


    In the process for removal of polycyclic aromatic hydrocarbons, asphatic tarry materials, and heterocyclic compounds from petroleum oil fractions by extraction with a selective solvent, with the aim of increasing the degree of purification and increasing the oil fraction yield, cyanomethyl acetate (I) or its aqueous solution is used as the solvent. I possesses a combination of high selectivity with sufficiently high dissolving capacity in relation to the undesirable oil fraction components. The extraction properties of I were studied both on artificial mixtures modelling the hydrocarbon part of petroleum oil fractions (tridecane + ..cap alpha..-methylnaphthalene) and on industrial oil fractions. The H/sub 2/O content in I can be from 0 to 10%. By reducing the water content of the extractant the yield and quality of the purified oil can be regulated. The solvent: feedstock ratio with the use of I or mixtures of it with H/sub 2/O is advisably maintained within the limits 0.5-3:1. Example -- Results are presented for a one-stage extraction of ..cap alpha..-methylnaphthalene from a mixture with tridecane at 20/sup 0/ and with a solvent:feedstock weight ratio of 1.5 in comparison with the use of furfurol as the selective solvent. In the proposed process the degree of extraction of ..cap alpha..-methylnaphthalene is 57% as against 55.6%; the tridecane content in the raffinate is 80.9% as against 79.3%; the degree of tridecane extraction is 97.5% as against 92%, and the raffinate yield is 78.5% as against 75.3%. In a multistage extraction process the advantages of I will be still more substantial.

  7. Chromatography purification of canine adenoviral vectors. (United States)

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


    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.

  8. Drinking water safety and the development of purification technology

    Institute of Scientific and Technical Information of China (English)

    Li Guibai


    This paper briefly introduced the evolution of purification technology for drinking water over time. After description of the 1st generation processes in the beginning of the 20th century -- conventional processes and the 2nd generation processes in 1970s -- advanced treatment processes, a tertiary processes -- UF (ultrafiltration) based on integrated processes was proposed. Moreover, reaction measures (dosing variety of regents for different contaminants) for urban source water emergencies.were illustrated in brief. A new technology of KMnO4 and potassium permanganate composite (PPC) for drinking water purification which was developed by Harbin Institute of Technology (HIT) was concisely introduced.

  9. Solid support resins and affinity purification mass spectrometry. (United States)

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


    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.

  10. Purification of Murine Monoclonal IgM Antibody

    Institute of Scientific and Technical Information of China (English)


    This paper presents the purification of a monoclonal IgM antibody against human tumor associated antigen Lewis-Y by ion exchange chromatography and gel filtration.Enzyme-linked immunosorbent assay (ELISA) and SDS-polyacrylamide gel electrophoresis (PAGE) were used to identify purified IgM antibody.In flow cytometry analysis, the purified IgM antibody recognizes human breast tumor cell line MCF-7 which expresses Lewis-Y antigen.This work presents a new way for the purification of murine monoclonal IgM antibody.

  11. High quality protein microarray using in situ protein purification

    Directory of Open Access Journals (Sweden)

    Fleischmann Robert D


    Full Text Available Abstract 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

  12. Isolation and purification of antigenic components of Cryptococcus. (United States)

    Wozniak, Karen L; Levitz, Stuart M


    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.

  13. Expression and purification of splicing proteins from mammalian cells. (United States)

    Allemand, Eric; Hastings, Michelle L


    Pre-mRNA splicing is a complex process that is carried out by a large ribonucleoprotein enzyme, termed the spliceosome, which comprises up to 200 proteins. Despite this complexity, the role of individual spliceosomal proteins in the splicing reaction has been successfully investigated using cell-free assays. In many cases, the splicing factor of interest must be expressed and purified in order to study its function in vitro. Posttranslational modifications such as phosphorylation, methylation, acetylation, and ubiquitination of splicing factors are important for activity. Thus, their purification from mammalian cells presents numerous advantages. Here, we describe a method for expression and purification of splicing proteins from mammalian cells.

  14. Plant lipases: partial purification of Carica papaya lipase. (United States)

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


    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.


    Institute of Scientific and Technical Information of China (English)

    WangHaifeng; XuYutai; 等


    Separation and purification of human chorionic gonadotropion(HCG) in the urine sample of early pregnant women by D3520 resin adsorption chromatography is reported.The crude product obtained by DEAE-Cellulose 23 and DEAE-Sephadex A50 column chromatography showed a high activity of HCG. Further purification of the sample by gel filtration chromatography on a Sephadex G75 column gives a final preparation of 6000-6500 IU/mg.The preparation meets the requirements of the pyrogn test in Chinese Law of Pharmacopeia.

  16. Fundamental limitations in the purifications of tensor networks (United States)

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


    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.

  17. Advantages for passengers and cabin crew of operating a Gas-Phase Adsorption air purifier in 11-h simulated flights

    DEFF Research Database (Denmark)

    Strøm-Tejsen, Peter; Zukowska, Daria; Fang, Lei


    Experiments were carried out in a 3-row, 21-seat section of a simulated aircraft cabin installed in a climate chamber to evaluate the extent to which passengers’ perception of cabin air quality is affected by the operation of a Gas-Phase Adsorption (GPA) purification unit. A total of 68 subjects......, divided into four groups of 17 subjects took part in simulated 11-hour flights. Each group experienced 4 conditions in balanced order, defined by two outside air supply rates (2.4 and 3.3 L/s per person), with and without the GPA purification unit installed in the recirculated air system. During each...... flight the subjects completed questionnaires five times to provide subjective assessments of air quality, cabin environment, intensity of symptoms, and thermal comfort. Additionally, the subjects’ visual acuity, finger temperature, skin dryness and nasal peak flow were measured three times during each...

  18. GSPEL - Air Filtration Laboratory (United States)

    Federal Laboratory Consortium — Evaluation capabilities for air filtration devices The Air Filtration Lab provides testing of air filtration devices to demonstrate and validate new or legacy system...

  19. 客机座舱气态污染物及其净化技术现状%Review of gaseous pollutants in aircraft cabin and purification technologies

    Institute of Scientific and Technical Information of China (English)

    陆义; 裴晶晶; 韩旭; 刘鲁萌; 刘俊杰


    介绍了客机座舱环境的特点与飞机环境控制系统中的通风净化系统,给出了国外关于机舱内空气质量的实际调查结果,总结了目前新风中臭氧处理的方法及可能面临的问题,对可用于回风中挥发性有机化合物处理的几种技术及其利弊进行了分析对比,探讨了机舱空气净化技术的发展方向。%Presents the characteristics of aircraft cabin environment and the ventilation purification system of its environmental control system.Gives survey results of cabin air quality,and summarizes ozone treatment methods in cabin outdoor air systems and potential problems.Analyses and compares several technologies that can be used for removal of volatile organic compounds in cabin return air systems. Discusses the developing orientation of cabin air purification technology.

  20. Air-to-Air Missile Vector Scoring (United States)


    64 4.6. Unscented Kalman Filter Performance in Air-to-Air Missile Scor - ing Application with Continuous Velocity Dynamics Model (Tar- get...Filter Performance in Air-to-Air Missile Scor - ing Application with Continuous Velocity Dynamics Model (Tar- get Aircraft Executing a Vertical Climb...Kalman Filter Performance in Air-to-Air Missile Scor - ing Application with Continuous Velocity Dynamics Model (Tar- get Aircraft Non-maneuvering

  1. Cardiopulmonary Benefits of Reducing Indoor Particles of Outdoor Origin: a Randomized Double-Blind Crossover Trial of Air Purifiers (United States)

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


    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


    Directory of Open Access Journals (Sweden)

    Bagus Anggaraditya Anggaraditya


    purification, hal ini mengingatkan kita untuk menjaga keseimbangan Agent, Host, dan Environment.Gangguan pada environment (lingkungan, alam di sekitar kita, akhirnya menyebabkan ketidakseimbangan di sebuah daerah dan akhirnya membawa bencana di wilayah tersebut. Kata kunci: Kolera, Sterilisasi, Saluran, Sumber, Pengolahan Air, Modifikasi gaya hidup.

  3. R9 Air Districts (United States)

    U.S. Environmental Protection Agency — The Region 9 Air Districts layer is a compilation of polygons representing the California Air Pollution Control and Air Quality Management Districts, Arizona Air...

  4. AirData (United States)

    U.S. Environmental Protection Agency — 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...

  5. California Air Basins (United States)

    California Department of Resources — Air ResourcesCalifornia Air Resources BoardThe following datasets are from the California Air Resources Board: * arb_california_airbasins - California Air BasinsThe...

  6. Purification of highly chlorinated dioxins degrading enzyme

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, K.; Furuichi, T.; Koike, K.; Kuboshima, M. [Hokkaido Univ. (Japan). Division of Environment Resource Engineering, Graduate School of Engineering


    Soil contamination caused by dioxins in and around sites of incinerators for municipal solid waste (MSW) is a concern in Japan. For example, scattering wastewater from a wet gas scrubber at an MSW incinerator facility in Nose, Osaka caused soil and surface water contamination. The concentration of dioxins in the soil was about 8,000 pg-TEQ/g. Other contamination sites include soils on which fly ash has been placed directly or improperly stored and landfill sites that have received bottom and fly ash over a long period. Some countermeasures are required immediately at these dioxins-contaminated sites. We have previously developed bioreactor systems for dioxin-contaminated water and soil. We have shown that a fungus, Pseudallescheria boydii (P. boydii), isolated from activated sludge treating wastewater that contained dioxins, has the ability to degrade highly chlorinated dioxins. A reaction product of octachlorinated dibenzo-p-dioxin (OCDD) was identified as heptachlorinated dibenzo-p-dioxin. Therefore, one of the pathways for degradation of OCDD by this fungus was predicted to be as follows: OCDD is transformed by dechlorination and then one of the remaining aromatic rings is oxidized. To apply P. boydii to on-site technologies (e.g., bioreactor systems), as well as in situ technologies, enzyme treatment using a dioxin-degrading enzyme from P. boydii needs to be developed because P. boydii is a weak pathogenic fungus, known to cause opportunistic infection. As a result, we have studied enzyme purification of nonchlorinated dioxin, namely, dibenzo-pdioxin (DD). However, we did not try to identify enzymes capable of degrading highly chlorinated dioxins. This study has elucidated a method of enzyme assay for measuring OCDD-degrading activity, and has attempted to purify OCDD-degrading enzymes from P. boydii using enzyme assay. In addition, as first step toward purifying 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), 2,3,7,8-TCDD degradation tests were carried out

  7. Membrane concepts for blood purification : towards improved artificial kidney devices

    NARCIS (Netherlands)

    Tijink, M.S.L.


    The research presented in this thesis is about the fabrication and characterization of new membranes for blood purification. A novel membrane concept is proposed to combine diffusion and adsorption in one step to remove uremic retention solutes. A membrane with embedded functionalized particles, a s

  8. Characterization and partial purification of phospholipase D from human placenta

    DEFF Research Database (Denmark)

    Vinggaard, Anne Marie; Hansen, Harald S.


    We report the existence in the human placenta of a phosphatidylcholine- hydrolyzing phospholipase D (PLD) activity, which has been characterized and partially purified. Triton X-100 effectively solubilized PLD from the particulate fraction of human placenta in a dose-dependent manner. However....... The present results form the basis for further purification of a PLD from human tissue....

  9. 2D nanostructures for water purification: graphene and beyond. (United States)

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


    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.

  10. Turnkey Helium Purification and Liquefaction Plant for DARWIN, Australia (United States)

    Lindemann, U.; Boeck, S.; Blum, L.; Kurtcuoglu, K.


    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.

  11. Use and application of hydrophobic interaction chromatography for protein purification. (United States)

    McCue, Justin T


    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.

  12. Purification and correlated measurements of bipartite mixed states

    CERN Document Server

    Bouda, J; Bouda, Jan; Buzek, Vladimir


    We prove that all purifications of a non-factorable state (i.e., the state which cannot be expressed in a form $\\rho_{AB}=\\rho_A\\otimes\\rho_B$) are entangled. We also show that for any bipartite state there exists a pair of measurements which are correlated on this state if and only if the state is non-factorable.

  13. The Extraction and Purification of Stevioside from Stevia

    Institute of Scientific and Technical Information of China (English)

    李涛; 张慧; 王冉冉; 张祥敏; 张万青; 王延霞; 王丽娟; 田浩


    tevioside is a natural sweetener extracted from stevia,which is widely used in the food industry and the pharmacy.Centre on the extraction and purification of stevioside,using ADS-7 resin to extract stevioside through one single step,greatly shorten the p

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

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  15. Purification of bacteriocins using size-exclusion chromatography

    Directory of Open Access Journals (Sweden)

    Vivek K. Bajpai


    Full Text Available The bacteriocin purification involves following main steps. a. Extraction of cell-free-supernatant of bacteria. b. Ammonium sulfate precipitation. c. Dialysis. d. Diafiltration using PVP and e. Size-exclusion chromatography. However, depending on the nature of work, the compound could be further analyzed by reverse-phase HPLC, NMR, mass spectrometry and sequencing.

  16. An improved purification procedure for Leishmania RNA virus (LRV) (United States)

    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


    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

  17. Purification and deodorization of structured lipids by short path distillation

    DEFF Research Database (Denmark)

    Xu, Xuebing; Jacobsen, Charlotte; Nielsen, Nina Skall;


    Purification of structured lipids (SL), produced from lipase- catalyzed acidolysis of rapeseed oil and capric acid, and deodorization of randomized SL, produced from chemical randomization of fish oil and tricaprin, were studied in a bench-scale short path distillation (SPD). SL obtained from...

  18. Purification of gibberellin sub 53 -oxidase from spinach

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, T.M.; Zeevaart, J.A.D. (Michigan State Univ., East Lansing (USA))


    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.

  19. Optimization of membrane protein overexpression and purification using GFP fusions

    NARCIS (Netherlands)

    Drew, David; Lerch, Mirjam; Kunji, Edmund; Slotboom, Dirk-Jan; de Gier, Jan-Willem


    Optimizing conditions for the overexpression and purification of membrane proteins for functional and structural studies is usually a Laborious and time-consuming process. This process can be accelerated using membrane protein-GFP fusions(1-3), which allows direct monitoring and visualization of mem

  20. Purification of lanthanides for double beta decay experiments

    Energy Technology Data Exchange (ETDEWEB)

    Polischuk, O. G. [Institute for Nuclear Research, MSP 03680 Kyiv, Ukraine and INFN, Section of Rome, La Sapienza, I-00185 Rome (Italy); Barabash, A. S. [Institute of Theoretical and Experimental Physics, 117259 Moscow (Russian Federation); Belli, P. [INFN, Section of Rome Tor Vergata, I-00133 Rome (Italy); Bernabei, R. [INFN, Section of Rome Tor Vergata, I-00133 Rome, Italy and Department of Physics, University of Rome Tor Vergata, I-00133 Rome (Italy); Boiko, R. S.; Danevich, F. A.; Mokina, V. M.; Poda, D. V.; Tretyak, V. I. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Cappella, F.; Incicchitti, A. [INFN, Section of Rome La Sapienza, I-00185 Rome, Italy and Department of Physics, University of Rome La Sapienza, I-00185 Rome (Italy); Cerulli, R.; Laubenstein, M.; Nisi, S. [INFN, Gran Sasso National Laboratories, I-67100 Assergi (Aq) (Italy)


    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.

  1. Electrophoretic High Molecular Weight DNA Purification Enables Optical Mapping (United States)

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


    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.

  2. Rapid purification of HU protein from Halobacillus karajensis

    Directory of Open Access Journals (Sweden)

    Parinaz Ghadam


    Full Text Available The histone-like protein HU is the most-abundant DNA-binding protein in bacteria. The HU protein non-specifically binds and bends DNA as a hetero- or homodimer, and can participate in DNA supercoiling and DNA condensation. It also takes part in DNA functions such as replication, recombination, and repair. HU does not recognize any specific sequences but shows a certain degree of specificity to cruciform DNA and repair intermediates such as nick, gap, bulge, etc. To understand the features of HU binding to DNA and repair intermediates, a fast and easy HU protein purification method is required. Here we report a two-step purification procedure of HU from Halobacillus karajensis (the gram positive and moderately halophilic bacteria isolated from Karaj surface soil. The method of HU purification allows obtaining a pure non-tagged protein. Salting out and ion exchange chromatography were applied for purification, and the purified protein was identified by immunoblotting. Results showed that the molecular weight of the purified protein was approximately 11 kDa which is immunologically similar to the Bacillus subtilis HU protein (HBsu.

  3. Zein purification: the process, the product, market potential (United States)

    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 ...

  4. Purification and characterization of a soluble calnexin from human placenta

    DEFF Research Database (Denmark)

    Olsen, Dorthe T; Peng, Li; Træholt, Sofie D;


    Calreticulin (Crt) and calnexin (Cnx) are homologous endoplasmic reticulum (ER) chaperones involved in protein folding and quality control. Crt is a soluble ER luminal Mr 46 kDa protein and Cnx is a Mr 67kDa ER membrane protein. During purification of Crt from human placenta a soluble form of Cnx...

  5. Automated high-throughput protein purification using an ÄKTApurifier and a CETAC autosampler. (United States)

    Yoo, Daniel; Provchy, Justin; Park, Cynthia; Schulz, Craig; Walker, Kenneth


    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.

  6. Air Warfare (United States)


    undoubtedly begat the shield; poisonous gases were countered by the mask. Surely men on the surface of the earth will not have to submit to violent air, production methods and cost of helium are given in “Balloon and Airship Gases ,” a volume of the Ronald Aeronautic Library. 5 More complete...becomes and more inse - cure. We shall see later that even some of the men who were advancing in the path prescribed by the principle of mass

  7. An air quality assessment onboard an Oberon class submarine : HMCS Okanagan

    Energy Technology Data Exchange (ETDEWEB)

    Severs, Y.D.; Sabiston, B.H.


    The Defence and Civil Institute of Environmental Medicine (DCIEM) re-examined the air quality on an Oberon class submarine, the HMCS Okanagan, to determine if the atmosphere complied with Air Purification Standard BR 1326. The main objective of the assessment was to help in the development of future submarine air quality management. The information obtained from the Oberon class submarine could be readily applied to the Victoria class submarines. The assessment involved a trial aboard an Oberon under patrol conditions. The functional and detection capabilities of analytical air monitoring instruments were assessed for a 24-hour period to obtain data regarding the contaminants onboard the submarine. A profile of carbon dioxide accumulation and oxygen consumption was determined. This was followed by an assessment of the effectiveness of air purification such as carbon dioxide scrubbing, oxygen generation and snorting. Carbon monoxide was also monitored and carboxyhemoglobin was measured in both smokers and non-smokers. In order to determine if the sanitary or electrical systems, or engine exhaust posed any danger, ammonia, ozone and nitrous compounds were also measured. In addition, hydrogen, arsine and stibene were monitored to determine any possible danger from charging batteries. The health risks associated with aerosolized particles from cooking, smoking and exhaust gases were also measured. Results showed that all contaminants were within allowable limits. However, the study also confirmed that air purification measures on diesel submarines are minimal and poorly placed and that there is a lack of exhaust ventilation. Poor air exchange was worsened by compartmentalization and blackout curtains. Several recommendations were proposed to improve the management of air quality in Victoria class submarines. 18 refs., 2 tabs., 5 figs.

  8. Synthesis Gas Purification Purification des gaz de synthèse

    Directory of Open Access Journals (Sweden)

    Chiche D.


    Full Text Available Fischer-Tropsch (FT based B-XTL processes are attractive alternatives for future energy production. These processes aim at converting lignocellulosic biomass possibly in co-processing with petcoke, coal, or vacuum residues into synthetic biofuels. A gasification step converts the feed into a synthesis gas (CO and H2 mixture , which undergoes the Fischer-Tropsch reaction after H2/CO ratio adjustment and CO2 removal. However synthesis gas also contains various impurities that must be removed in order to prevent Fischer-Tropsch catalyst poisoning. Due to the large feedstocks variety that can be processed, significant variations of the composition of the synthesis gas are expected. Especially, this affects the nature of the impurities that are present (element, speciation, as well as their relative contents. Moreover, due to high FT catalyst sensitivity, severe syngas specifications regarding its purity are required. For these reasons, synthesis gas purification constitutes a major challenge for the development of B-XTL processes. In this article, we focus on these major hurdles that have to be overcome. The different kinds of syngas impurities are presented. The influence of the nature of feedstocks, gasification technology and operating conditions on the type and content of impurities is discussed. Highlight is given on the fate of sulfur compounds, nitrogen compounds, halides, transition and heavy metals. Main synthesis gas purification technologies (based on adsorption, absorption, catalytic reactions, etc. are finally described, as well as the related challenges. Les procédés de synthèse de biocarburants par voie Fischer-Tropsch (FT, voies B-XTL, représentent des alternatives prometteuses pour la production d’énergie. Ces procédés permettent la conversion en carburants de synthèse de biomasse lignocellulosique, éventuellement mise en oeuvre en mélange avec des charges fossiles telles que petcoke, charbons ou résidus sous vide. Pour

  9. Distillation and Air Stripping Designs for the Lunar Surface (United States)

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


    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

  10. Biofiltration of air contaminated with methanol and toluene

    Directory of Open Access Journals (Sweden)

    Pakamas Chetpattananondh


    Full Text Available Biofiltration of air contaminated with VOCs is inexpensive compared with the conventional techniques and very effective for treating large volumes of moist air streams with low concentrations of VOCs. In this study, biofiltration for the purification of polluted air from methanol, a hydrophilic VOC, and toluene, a hydrophobic VOC, was investigated. The experiments were operated using three separated stainless steel biofilters, for methanol, toluene, and a mixture of methanol and toluene, respectively. Biofilter consisted of a mixture of palm shells and activated sludge as a filter-bed material. Only the indigenous microorganisms of the bed medium without any addition of extra inoculum were used throughout the whole process. The polluted air inlet concentration was varied from 0.3-4.7 g/m3 with flow rates ranging from 0.06-0.45 m3/h, equivalent to the empty bed residence times of 9-71 sec. Polluted air was successfully treated by biofiltration, 100% removal efficiencies would be obtained when the air flow rate was lower than 0.45 m3/h. The presence of toluene did not affect the removal rate of methanol while the removal rate of toluene was decreased with the presence of methanol in air stream according to the competition phenomenon.

  11. Air and the origin of the experimental plant physiology. (United States)

    Pennazio, Sergio


    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.

  12. A synthetic zero air standard (United States)

    Pearce, Ruth


    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


    Directory of Open Access Journals (Sweden)

    V. V. Shitov


    Full Text Available Problem statement. A problem of mathematical modeling and intensification of operation of the flow thermal diffusion chamber of the condensation gravity filter as one of the most efficient air filter is solved.Results and conclusions. This paper presents an example of the practical application of the model of heat and mass exchange in the thermodiffusion chamber as the main operating element of condensation gravity filter for high-performance air purification due to the generation of supersaturation fields with controlled properties. A criterion for quantitative assessment of purification efficiency in the form of breakthrough function is developed. The typical results of numerical modeling of the operation of the condensation gravity-type filter are presented for the most common case in practice. The possibility of intensification of the filter operation either at the stage of use or at the stage of design is shown based on the proposed approach, obtained models, and calculations.

  14. 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. (United States)

    Spooner, Jennifer; Keen, Jenny; Nayyar, Kalpana; Birkett, Neil; Bond, Nicholas; Bannister, David; Tigue, Natalie; Higazi, Daniel; Kemp, Benjamin; Vaughan, Tristan; Kippen, Alistair; Buchanan, Andrew


    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.

  15. Air filtration and indoor air quality

    DEFF Research Database (Denmark)

    Bekö, Gabriel


    decent ventilation and air cleaning/air filtration, high indoor air quality cannot be accomplished. The need for effective air filtration has increased with increasing evidence on the hazardous effects of fine particles. Moreover, the air contains gaseous pollutants, removal of which requires various air....... These contradictions should motivate manufacturers and researchers to develop new efficient filtration techniques and/or improve the existing ones. Development of low polluting filtration techniques, which are at the same time easy and inexpensive to maintain is the way forward in the future....

  16. Chemical Protection Testing of Sorbent-Based Air Purification Components (APCs) (United States)


    extinguished IAW test center SOPs. For example, carbon dioxide fire extinguishers are not effective on burning carbon filters, which may be quenched by a...testing. BFC exposure chambers must have relief openings to prevent backpressure. Effluent from the APCs must be vented out of the BFC exposure...3.3.3 Fire, Pressure, and Explosion Hazard. a. Many filters contain activated carbon impregnated with copper, silver, zinc, molybdenum, and

  17. Low Cost, Efficient Microcavity Plasma Ozone Generation for Water Remediation and Air Purification (United States)


    two different values of the oxygen flow rate (0.5 L/min and 1.0 L/min). For these tests, the reactor comprised six microchannels each having a depth...this entire test, the reactor was not cooled (intentionally, running at ~50C) and the microchannels were driven with fast, high voltage pulses in an...Figure 8. A composite reactor , fabricated by stacking six layers of 6 parallel microchannels , was tested for gas flow rates of 0.5, 1.0 and 1.5 L/min


    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., ...

  19. The Blood Compatibilities of Blood Purification Membranes and Other Materials Developed in Japan

    Directory of Open Access Journals (Sweden)

    Takaya Abe


    Full Text Available 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.

  20. Liquid xenon purification, de-radonation (and de-kryptonation)

    Energy Technology Data Exchange (ETDEWEB)

    Pocar, Andrea, E-mail: [Amherst Center for Fundamental Interactions and Physics Department, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)


    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.

  1. A Scintillator Purification Plant and Fluid Handling System for SNO+

    CERN Document Server

    Ford, Richard J


    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.

  2. Water Purification by Shock Electrodialysis: Deionization, Filtration, Separation, and Disinfection

    CERN Document Server

    Deng, Daosheng; Braff, William A; Schlumpberger, Sven; Suss, Matthew E; Bazant, Martin Z


    The development of energy and infrastructure efficient water purification systems are among the most critical engineering challenges facing our society. Water purification is often a multi-step process involving filtration, desalination, and disinfection of a feedstream. Shock electrodialysis (shock ED) is a newly developed technique for water desalination, leveraging the formation of ion concentration polarization (ICP) zones and deionization shock waves in microscale pores near to an ion selective element. While shock ED has been demonstrated as an effective water desalination tool, we here present evidence of other simultaneous functionalities. We show that, unlike electrodialysis, shock ED can thoroughly filter micron-scale particles and aggregates of nanoparticles present in the feedwater. We also demonstrate that shock ED can enable disinfection of feedwaters, as approximately $99\\%$ of viable bacteria (here \\textit{E. coli}) in the inflow were killed or removed by our prototype. Shock ED also separates...

  3. Preparation and Purification of Zinc Sulphinate Reagents for Organic Synthesis (United States)

    O’Hara, Fionn; Baxter, Ryan D.; O’Brien, Alexander G.; Collins, Michael R.; Dixon, Janice A.; Fujiwara, Yuta; Ishihara, Yoshihiro; Baran, Phil S.


    SUMMARY The present protocol details the synthesis of zinc bis(alkanesulphinate)s that can be used as general reagents for the formation of radical species. The zinc sulphinates described herein have been generated from the corresponding sulphonyl chlorides by treatment with zinc dust. The products may be used crude, or a simple purification procedure may be performed to minimize incorporation of water and zinc chloride. Elemental analysis has been conducted in order to confirm the purity of the zinc sulphinate reagents; reactions with caffeine have also been carried out to verify the reactivity of each batch that has been synthesized. Although the synthesis of the zinc sulphinate salts generally proceeds within 3 h, workup can take up to 24 h and purification can take up to 3 h. Following the steps in this protocol would enable the user to generate a small toolkit of zinc sulphinate reagents over the course of one week. PMID:23640168

  4. Purification effects of glass flux on A356 melt

    Institute of Scientific and Technical Information of China (English)

    倪红军; 孙宝德; 蒋海燕; 陈晨; 丁文江


    In order to remove hydrogen and inclusions from A356 alloy melt,a low melting-point glass flux,JDN-Ⅱ,was developed.The results indicated that JDN-Ⅱ flux has distinct effect of purification and protection on A356 alloy melt.When the dosage of the flux was 3%,the content of hydrogen in A356 melt was only 2.6 mL/kg at 857 ℃ and 0.7 mL/kg even at 750 ℃.In the meantime,the mechanical properties of the alloy increase greatly with the covering of 3% JDN-Ⅱ flux.Compared with no flux,the tensile strength of A356 alloy increases by 9.42% and the elongation increases by 22%.The purification mechanism of JDN-Ⅱ glass flux was discussed too.

  5. Purification of Chironex fleckeri venom components using Chironex immunoaffinity chromatography. (United States)

    Naguib, A M; Bansal, J; Calton, G J; Burnett, J W


    A comparison of the purification of the nematocyst venom of Chironex fleckeri by affinity immunochromatography using 13 different monoclonal antibodies was made. Varying degrees of purification of mouse lethal factor, hemolysin and dermonecrotic factors, as well as antigen positive proteins were achieved with each of the monoclonal antibodies. Although the protein curves of the chromatography were similar, each of the monoclonal antibody columns had a distinctive pharmacological and SDS-PAGE profile. At least two hemolysins (120,000 and 70,000 molecular weight), two dermonecrotic principles (120,000, less than 120,000) and three lethal factors (120,000, 70,000 and 14,500 molecular weight) were detected. The degree to which aggregation and fragmentation affects the molecular weights of these proteins is not known. It appears that multiple pharmacological activities are present within the same molecule since it is only with great difficulty that a pharmacological activity can be assigned to a specific molecular weight.

  6. Purification and characterization of a soluble calnexin from human placenta. (United States)

    Olsen, Dorthe T; Peng, Li; Træholt, Sofie D; Duus, Karen; Højrup, Peter; Houen, Gunnar


    Calreticulin (Crt) and calnexin (Cnx) are homologous endoplasmic reticulum (ER) chaperones involved in protein folding and quality control. Crt is a soluble ER luminal Mr 46 kDa protein and Cnx is a Mr 67kDa ER membrane protein. During purification of Crt from human placenta a soluble form of Cnx (sCnx) was consistently identified in a separate ion exchange chromatography peak. The sCnx was further purified and characterised. This showed that the protein had been cleaved after residue 472 (between Gln and Met), thus liberating it from the transmembrane and cytoplasmic parts of Cnx. The extraction and initial purification steps were carried out in the presence of protease inhibitors, thus ruling out that the cleavage was an artefact of the isolation procedure. This indicates that sCnx may have a physiological chaperone function similar to that of Crt.

  7. Expression, Solubilization, and Purification of Bacterial Membrane Proteins. (United States)

    Jeffery, Constance J


    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.

  8. Stabilization of high mercury contaminated brine purification sludge. (United States)

    Zhuang, J Ming; Lo, Tony; Walsh, Tony; Lam, Tak


    The highly leachable mercury contaminants of brine purification sludge (BPS) generated from the Hg-cell electrolysis process in chlorine production can be stabilized in the treatment procedure employing ferric-lignin derivatives (FLD) (Ligmet binder) and Portland cement (PC). The stabilization effectiveness has been examined by time-based multiple toxicity characteristic leaching procedure (TCLP) tests and sequential TCLP tests. In a period of 50 days, the multiple TCLP tests showed a variation of less than 90 microg l(-1) for the leachable mercury level, and the sequential TCLP tests for the same sample displayed a declining TCLP mercury level. Based on this study, the stabilization of approximately 2000 t of brine purification sludge has been successfully processed with the ferric-lignin derivatives treatment.

  9. Treatment of hyperbilirubinemia with blood purification in China

    Institute of Scientific and Technical Information of China (English)

    Zhi-Jun Duan; Lei-Lei Li; Jia Ju; Zhi-Hong Gao; Gao-Hong He


    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.

  10. Preparative Purification of Recombinant Proteins: Current Status and Future Trends

    Directory of Open Access Journals (Sweden)

    Mayank Saraswat


    Full Text Available 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.

  11. Uranium hexafluoride purification; Purificacao de hexafluoreto de uranio

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Eneas F. de


    Uranium hexafluoride might contain a large amount of impurities after manufacturing or handling. Three usual methods of purification of uranium hexafluoride were presented: selective sorption, sublimation, and distillation. Since uranium hexafluoride usually is contaminated with hydrogen fluoride, a theoretical study of the phase equilibrium properties was performed for the binary system UF{sub 6}-HF. A large deviation from the ideal solution behaviour was observed. A purification unity based on a constant reflux batch distillation process was developed. A procedure was established in order to design the re boiler, condenser and packed columns for the UF{sub 6}-HF mixture separation. A bench scale facility for fractional distillation of uranium hexafluoride was described. Basic operations for that facility and results extracted from several batches were discussed. (author)

  12. Minicircle DNA purification using a CIM® DEAE-1 monolithic support. (United States)

    Diamantino, Tatiana; Pereira, Patrícia; Queiroz, João A; Sousa, Ângela; Sousa, Fani


    Minicircle DNA is a new biotechnological product with beneficial therapeutic perspectives for gene therapy because it is constituted only by the eukaryotic transcription unit. These features improve minicircle DNA safety and increase its therapeutic effect. However, being a recently developed product, there is a need to establish efficient purification methodologies, enabling the recovery of the supercoiled minicircle DNA isoform. Thus, this work describes the minicircle DNA purification using an anion exchange monolithic support. The results show that with this column it is possible to achieve a good selectivity, which allows the isolation of the supercoiled minicircle DNA isoform from impurities. Overall, this study shows a promising approach to obtain the minicircle DNA sample with adequate quality for future therapeutic applications.

  13. Recombinant Dragline Silk-Like Proteins—Expression and Purification (United States)

    Gaines, William A.; Marcotte, William R.


    Spider dragline silk is a proteinaceous fiber with impressive physical characteristics making it attractive for use in advanced materials. The fiber is composed of two proteins (spidroins MaSp1 and MaSp2), each of which contains a large central repeat array flanked by non-repetitive N- and C-terminal domains. The repeat arrays appear to be largely responsible for the tensile properties of the fiber, suggesting that the N- and C-terminal domains may be involved in self-assembly. We recently isolated the MaSp1 and MaSp2 N-terminal domains from Nephila clavipes and have incorporated these into mini-silk genes for expression in transgenic systems. Current efforts involve the development of expression vectors that will allow purification using a removable affinity tag for scalable protein purification. PMID:23914141

  14. Recombinant Dragline Silk-Like Proteins-Expression and Purification. (United States)

    Gaines, William A; Marcotte, William R


    Spider dragline silk is a proteinaceous fiber with impressive physical characteristics making it attractive for use in advanced materials. The fiber is composed of two proteins (spidroins MaSp1 and MaSp2), each of which contains a large central repeat array flanked by non-repetitive N- and C-terminal domains. The repeat arrays appear to be largely responsible for the tensile properties of the fiber, suggesting that the N- and C-terminal domains may be involved in self-assembly. We recently isolated the MaSp1 and MaSp2 N-terminal domains from Nephila clavipes and have incorporated these into mini-silk genes for expression in transgenic systems. Current efforts involve the development of expression vectors that will allow purification using a removable affinity tag for scalable protein purification.

  15. Affinity Purification of Insulin by Peptide-Ligand Affinity Chromatography

    Institute of Scientific and Technical Information of China (English)


    The affinity heptapeptide (HWWWPAS) for insulin, selected from phage display library,was coupled to EAH Sepharose 4B gel and packed to a 1-mL column. The column was used for the affinity purification of insulin from protein mixture and commercial insulin preparation. It was observed that the minor impurity in the commercial insulin was removed by the affinity chromatography. Nearly 40 mg of insulin could be purified with the 1-mL affinity column. The results revealed the high specificity and capacity of the affinity column for insulin purification. Moreover, based on the analysis of the amino acids in the peptide sequence, shorter peptides were designed and synthesized for insulin chromatography. As a result, HWWPS was found to be a good alternative to HWWWPAS, while the other two peptides with three or four amino acids showed weak affinity for insulin. The results indicated that the peptide sequence of HWWWPAS was quite conservative for specific binding of insulin.

  16. Purification of carbon nanotube by wet oxidation; Shisshiki sanka ni yoru carbon nanotube no seisei

    Energy Technology Data Exchange (ETDEWEB)

    Morishita, K.; Takarada, T. [Gunma University, Gunma (Japan)


    In order to efficiently recover carbon nanotubes, the purification method by wet oxidation with orthoperiodic acid and perchloric acid is investigated. The reactivity of the carbonaceous material toward the acids depends on the type of carbon. Carbon nanotubes are selectively recovered under the mild oxidation conditions. The degree of purification depends on the concentration of orthoperiodic acid. It is suggested that wet oxidation is an effective method for purification of carbon nanotubes. 17 refs., 6 figs.

  17. Air pollution

    Energy Technology Data Exchange (ETDEWEB)


    Air pollution conditions in Iwakuni city were monitored at 9 monitoring stations, and 21 locations where sulfur oxides were measured by the lead peroxide candle method, and 13 locations where particulates concentrations were determined by the deposit cage method. The average SO/sub x/ concentrations in 1973 measured by the lead peroxide candle method ranged from 0.17 mg sulfur trioxide/day/100 sq cm at the Miso Office to 0.58 mg SO/sub 3//day/100 sq cm at Mitsui Sekiyu Shataku. The average SO/sub x/ concentrations measured by the conductivity method ranged from 0.021 ppM at Kazuki Kominkan to 0.037 ppM at the Higashi Fire Department. Only 58% of a total of 264 measurement days gave hourly average concentrations below the environmental standard of 0.04 ppM at the Higashi Fire Deparment. The average airborne particulate concentrations ranged from 0.050 mg/cu m at Totsu Kominkan to 0.056 mg/cu at the Higashi Fire Department. The average nitrogen oxides concentrations measured by the Saltzman method ranged from 0.007 ppM to 0.061 ppM. The average oxidant concentrations at the Iwakuni Municipal Office and Kazuki Kominkan were 0.028 ppM and 0.037 ppM, respectively.

  18. Partial purification of protective antigens from Nippostrongylus brasiliensis in mice. (United States)

    Rhalem, A; Bourdieu, C; Luffau, G; Pery, P


    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.

  19. Ecological aspects of the extreme purification of water (United States)

    Shaposhnik, Vladimir A.; Mazo, A. A.; Frölich, P.


    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.

  20. Reverse osmosis membrane of high urea rejection properties. [water purification (United States)

    Johnson, C. C.; Wydeven, T. J. (Inventor)


    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.

  1. Aqueous Chloride Operations Overview: Plutonium and Americium Purification/Recovery

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, Kyle Shelton [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kimball, David Bryan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Skidmore, Bradley Evan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    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.

  2. Affinity chromatography purification of cytochrome c binding enzymes.


    Azzi, A; Bill, K; Broger, C


    An efficient affinity chromatography procedure for the isolation of mitochondrial cytochrome c oxidase and reductase is described. Saccharomyces cerevisiae cytochrome c was used as a ligand, bound to a thiol-Sepharose 4B gel through cysteine-107. In this way, the site of interaction of cytochrome c with cytochrome oxidase and reductase remained unmodified and available for binding to a number of partner enzymes. The procedure is adequate for the purification of all those proteins having in co...

  3. Affinity purification of sequence-specific DNA binding proteins.



    We describe a method for affinity purification of sequence-specific DNA binding proteins that is fast and effective. Complementary chemically synthesized oligodeoxynucleotides that contain a recognition site for a sequence-specific DNA binding protein are annealed and ligated to give oligomers. This DNA is then covalently coupled to Sepharose CL-2B with cyanogen bromide to yield the affinity resin. A partially purified protein fraction is combined with competitor DNA and subsequently passed t...

  4. Chromatographic and electrophoretic methods for nanodisc purification and analysis

    DEFF Research Database (Denmark)

    Justesen, Bo Højen; Günther-Pomorski, Thomas


    Soluble nanoscale lipid bilayers, termed nanodiscs, are widely used in science for studying the membrane-anchored and integral membrane protein complexes under defined experimental conditions. Although their formation occurs by a self-assembly process, nanodisc purification and the verification...... of proper reconstitution are still major challenges during the sample preparation. This review gives an overview of the methods used for purifying and analyzing nanodiscs and nanodisc-reconstituted membrane proteins, with an emphasis on the chromatographic and electrophoretic approaches....

  5. Expression, purification, and immobilization of recombinant tamavidin 2 fusion proteins. (United States)

    Takakura, Yoshimitsu; Oka, Naomi; Tsunashima, Masako


    Tamavidin 2 is a fungal avidin-like protein that binds biotin with high affinity. Unlike avidin or streptavidin, tamavidin 2 in soluble form is produced at high levels in Escherichia coli. In this chapter, we describe a method for immobilization and purification of recombinant proteins with the use of tamavidin 2 as an affinity tag. The protein fused to tamavidin 2 is tightly immobilized and simultaneously purified on biotinylated magnetic microbeads without loss of activity.

  6. Optimality of feedback control strategies for qubit purification


    Wiseman, Howard M.; Bouten, Luc


    Recently two papers [K. Jacobs, Phys. Rev. A {\\bf 67}, 030301(R) (2003); H. M. Wiseman and J. F. Ralph, New J. Physics {\\bf 8}, 90 (2006)] have derived control strategies for rapid purification of qubits, optimized with respect to various goals. In the former paper the proof of optimality was not mathematically rigorous, while the latter gave only heuristic arguments for optimality. In this paper we provide rigorous proofs of optimality in all cases, by applying simple concepts from optimal c...

  7. Purification and characterization of osteopontin from human milk

    DEFF Research Database (Denmark)

    Sørensen, Steen; Justesen, Steen Just; Johnsen, Anders H


    separated into its different molecular forms by means of a two-step procedure, involving size exclusion chromatography and reverse phase chromatography. A rabbit polyclonal antibody was raised to purified intact OPN and high M(r) OPN components; the immunoreactivity of both forms was almost equal when...... investigated by enzyme immunoassay (EIA). The procedures facilitate the purification of intact OPN and OPN fragments for purposes of standardization, preparation of monospecific antibodies, and functional studies....

  8. The Flotational Mechanism of Etobicoke Creek's Self-Purification

    CERN Document Server

    Fisenko, A I


    A flotational mechanism of Etobicoke Creek's self-purification has been investigated. It is shown that the froth contains a high concentration of polluting agents. Chemical analyses of the top layer of surface water in comparison to both before and after froth collector in the course of a year are provided. As a result, the concentrations of pollutants by utilizing the model froth collector are decreased.



    Gusti Wahdaniyah*, Purnomo Tri Prasetyo, Arif Setiabudi, Totok R. Biyanto


    The purpose of this paper is to describe the filtration or purification of transformer oil. One of the main equipment in coal-fired power generation unit is transformer. When the transformer fail to operate properly, the continuity of distribution system become interrupted. As a part of transformer, transformer oil contribute the failure of transformer due to the aging. To solve this problem, several methods is applied starting from dehydration process, degasification process, oxidation remov...

  10. Purification of Lamins and Soluble Fragments of NETs. (United States)

    Makarov, Alexandr A; Rizzotto, Andrea; Meinke, Peter; Schirmer, Eric C


    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.

  11. Solid-Phase Purification of Synthetic DNA Sequences. (United States)

    Grajkowski, Andrzej; Cieslak, Jacek; Beaucage, Serge L


    Although high-throughput methods for solid-phase synthesis of DNA sequences are currently available for synthetic biology applications and technologies for large-scale production of nucleic acid-based drugs have been exploited for various therapeutic indications, little has been done to develop high-throughput procedures for the purification of synthetic nucleic acid sequences. An efficient process for purification of phosphorothioate and native DNA sequences is described herein. This process consists of functionalizing commercial aminopropylated silica gel with aminooxyalkyl functions to enable capture of DNA sequences carrying a 5'-siloxyl ether linker with a "keto" function through an oximation reaction. Deoxyribonucleoside phosphoramidites functionalized with the 5'-siloxyl ether linker were prepared in yields of 75-83% and incorporated last into the solid-phase assembly of DNA sequences. Capture of nucleobase- and phosphate-deprotected DNA sequences released from the synthesis support is demonstrated to proceed near quantitatively. After shorter than full-length DNA sequences were washed from the capture support, the purified DNA sequences were released from this support upon treatment with tetra-n-butylammonium fluoride in dry DMSO. The purity of released DNA sequences exceeds 98%. The scalability and high-throughput features of the purification process are demonstrated without sacrificing purity of the DNA sequences.

  12. Large-scale functional purification of recombinant HIV-1 capsid.

    Directory of Open Access Journals (Sweden)

    Magdeleine Hung

    Full Text Available During human immunodeficiency virus type-1 (HIV-1 virion maturation, capsid proteins undergo a major rearrangement to form a conical core that protects the viral nucleoprotein complexes. Mutations in the capsid sequence that alter the stability of the capsid core are deleterious to viral infectivity and replication. Recently, capsid assembly has become an attractive target for the development of a new generation of anti-retroviral agents. Drug screening efforts and subsequent structural and mechanistic studies require gram quantities of active, homogeneous and pure protein. Conventional means of laboratory purification of Escherichia coli expressed recombinant capsid protein rely on column chromatography steps that are not amenable to large-scale production. Here we present a function-based purification of wild-type and quadruple mutant capsid proteins, which relies on the inherent propensity of capsid protein to polymerize and depolymerize. This method does not require the packing of sizable chromatography columns and can generate double-digit gram quantities of functionally and biochemically well-behaved proteins with greater than 98% purity. We have used the purified capsid protein to characterize two known assembly inhibitors in our in-house developed polymerization assay and to measure their binding affinities. Our capsid purification procedure provides a robust method for purifying large quantities of a key protein in the HIV-1 life cycle, facilitating identification of the next generation anti-HIV agents.

  13. Development of EV71 virus-like particle purification processes. (United States)

    Lin, Shih-Yeh; Chiu, Hsin-Yi; Chiang, Bor-Luen; Hu, Yu-Chen


    Enterovirus 71 (EV71) causes the outbreaks of hand-foot-and-mouth disease and results in deaths of hundreds of young children. EV71 virus-like particles (VLPs) are empty capsids consisting of viral structural proteins and can elicit potent immune responses, thus holding promise as an EV71 vaccine candidate. However, an efficient, scalable production and purification scheme is missing. For mass production of EV71 VLPs, this study aimed to develop a production and chromatography-based purification process. We first demonstrated the successful EV71 VLPs production in the stirred-tank bioreactor in which High Five™ cells were infected with a recombinant baculovirus co-expressing EV71 structural polyprotein P1 and protease 3CD. The culture supernatant containing the VLPs was subjected to tangential flow filtration (TFF) for concentration/diafiltration, which enabled the removal of >80% of proteins while recovering >80% of VLPs. The concentrated VLPs were next subjected to hydroxyapatite chromatography (HAC) in which the VLPs were mainly found in the flow through. After another TFF concentration/diafiltration, the VLPs were purified by size-exclusion chromatography (SEC) and concentrated/diafiltered by a final TFF. The integrated process yielded an overall VLPs recovery of ≈ 36% and a purity of ≈ 83%, which was better or comparable to the recovery and purity for the purification of live EV71 virus particles. This process thus may move the EV71 VLPs vaccine one step closer to the clinical applications.

  14. Matching relations for optimal entanglement concentration and purification. (United States)

    Kong, Fan-Zhen; Xia, Hui-Zhi; Yang, Ming; Yang, Qing; Cao, Zhuo-Liang


    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.

  15. Current topics of purification and constitutions of dialysis fluid. (United States)

    Tomo, Tadashi


    Dialysis fluid is a fundamental component of hemodialysis treatment, and its roles include the correction of electrolyte levels, pH, and osmolality, as well as the removal of uremic solutes from the blood of patients with renal failure. In recent years, purification of dialysis fluid has become essential due to the use of high-flux membrane dialyzers. Therefore, rigorous standards have been established for the purification of dialysis fluid, which is becoming widely practiced in Japan. The effects of dialysis fluid purification include the prevention of micro-inflammation, preservation of residual renal function, improvement of nutritional status, and resolution of resistance to erythropoiesis-stimulating agents. When purifying the dialysis fluid used in the central dialysis fluid delivery system, validation of the system is also important. Dialysis fluid that does not contain acetate has become available, and there have been reports of decreased micro-inflammation, etc., with this innovation. In addition, dialysis fluid containing a higher concentration of bicarbonate than is conventionally employed has become available. Although correction of acidosis remains important, excess alkalosis may reportedly worsen the survival prognosis of hemodialysis patients. Sufficient attention should be paid to these issues.

  16. Protein purification and crystallization artifacts: The tale usually not told. (United States)

    Niedzialkowska, Ewa; Gasiorowska, Olga; Handing, Katarzyna B; Majorek, Karolina A; Porebski, Przemyslaw J; Shabalin, Ivan G; Zasadzinska, Ewelina; Cymborowski, Marcin; Minor, Wladek


    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.

  17. Purification of a Multidrug Resistance Transporter for Crystallization Studies

    Directory of Open Access Journals (Sweden)

    Kamela O. Alegre


    Full Text Available 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.

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

    Directory of Open Access Journals (Sweden)

    Di-Hua Li


    Full Text Available 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.

  19. Purification of coagulation factor VIII by immobilized metal affinity chromatography. (United States)

    Rodrigues, Estela S; Verinaud, Claudia I; Oliveira, Douglas S; Raw, Isaías; Lopes, Alexandre P Y; Martins, Elizabeth A L; Cheng, Elisabeth


    Factor VIII (FVIII) is a glycoprotein that plays an essential role in blood coagulation cascade. Purification of plasma-derived coagulation FVIII by direct application of plasma to a chromatographic column is a method of choice. Anion exchange column is a very powerful method because FVIII is strongly adsorbed, resulting in good activity recovery and high purification factor. However, vitamin-K-dependent coagulation factors coelute with FVIII. In the present study, we report the separation of vitamin-K-dependent coagulation proteins from FVIII using immobilized metal affinity chromatography (IMAC) with Cu(2+) as the metal ligand. Plasma was directly loaded to a Q Sepharose Big Beads column, and FVIII was recovered with 65% activity and a purification factor of approximately 50 times. Then, the Q Sepharose eluate was applied to the IMAC-Cu(2+) column, and FVIII was eluted with 200 mM imidazole, with up to 85% recovery of activity. The mass recovery in this fraction was less than 10% of the applied mass of protein. Vitamin-K-dependent proteins elute with imidazole concentrations of lower than 60 mM. Because of the difference in affinity, FVIII could be completely separated from the vitamin-K-dependent proteins in the IMAC column.

  20. Simple method for purification of enterotoxigenic Escherichia coli fimbriae. (United States)

    Curtis, Brittany; Grassel, Christen; Laufer, Rachel S; Sears, Khandra T; Pasetti, Marcela F; Barry, Eileen M; Simon, Raphael


    Enterotoxigenic Escherichia 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.

  1. [Separation and purification of cellulase using affinity membrane]. (United States)

    Shi, Xiang-zhu; Guo, Chun-teng; Zhou, Jian-wu; Wang, Zhong-lai; Rao, Ping-fan


    The importance of cellulase as a means for the efficient utilization of abundant cellulose resources in the world has been well recognized. Many researchers devote themselves to studying the mechanism of the action of cellulase to cellulose so that such expensive enzyme can be used much more widely. The first step is to obtain cellulase of high purity. So purification of cellulase is the key point in this field. However, the major problem in isolation is that cellulase is a complicated enzyme system and needs too many steps for separation, and that every cellulase needs special purification processing which cannot be used for the others. A novel method for the separation of the cellulase from crude extraction of Aspergillus niger with normal qualitative filter paper processed by 5 mol/L sodium hydroxide without precipitation and desalting steps was developed. Further purification of the cellulase was achieved by using an anion-exchange column of POROS 20HQ. The cellulase purified was identified as a new endoglucanase that had relatively high endurance to pH and temperature. Its relative molecular mass was estimated to be 60,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This enzyme exhibited very high activity towards carboxymethyl cellulose (CMC) with specific activity of 350 and the recovery of activity of 9.7%. Its optimum pH and temperature were 4.0 and 70 degrees C, respectively. This is a simple, rapid and efficient method for purifying cellulase with high activity.

  2. Purification for the XENONnT dark matter experiment (United States)

    Brown, Ethan; Xenon Collaboration


    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.

  3. Recent advances in production,purification and applications of phycobiliproteins

    Institute of Scientific and Technical Information of China (English)

    Ravi Raghav Sonani; Rajesh Prasad Rastogi; Rutvij Patel; Datta Madamwar


    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, antioxidants, 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.

  4. The modified swirl sedimentation tanks for water purification. (United States)

    Ochowiak, Marek; Matuszak, Magdalena; Włodarczak, Sylwia; Ancukiewicz, Małgorzata; Krupińska, Andżelika


    This paper discusses design, evaluation, and application for the use of swirl/vortex technologies as liquid purification system. A study was performed using modified swirl sedimentation tanks. The vortex separators (OW, OWK, OWR and OWKR) have been studied under laboratory conditions at liquid flow rate from 2.8⋅10(-5) to 5.1⋅10(-4) [m(3)/s]. The pressure drop and the efficiency of purification of liquid stream were analyzed. The suspended particles of different diameters were successfully removed from liquid with the application of swirl chambers of proposed constructions. It was found that damming of liquid in the tank increases alongside liquid stream at the inlet and depends on the tank construction. The efficiency of the sedimentation tanks increases alongside the diameters of solid particles and decrease in the liquid flow rate. The best construction proved to be the OWR sedimentation tank due to smallest liquid damming, even at high flow rates, and the highest efficiency of the purification liquid stream for solid particles of the smallest diameter. The proposed solution is an alternative to the classical constructions of sedimentation tanks.

  5. Interview with Dr Robin Rothrock: the RNA purification market. 26 July 2005. (United States)

    Alger, Lynsey


    Dr Robin Rothrock, Director of Market Research at Bioinformatics LLC, talked to Lynsey Alger about the RNA purification market. The process of RNA purification is one of growing importance, not only among basic researchers, but increasingly among those involved in clinical research, particularly as purified RNA represents the base material for a vast number of innovative and widely used techniques, such as real-time and reverse transcriptase polymerase chain reaction and DNA microarrays. This interview examines the current and future status of the RNA purification market, with a focus on the different types of purification approaches available to researchers as well as the key companies involved in their production.

  6. Air Sensor Toolbox (United States)

    Air Sensor Toolbox provides information to citizen scientists, researchers and developers interested in learning more about new lower-cost compact air sensor technologies and tools for measuring air quality.

  7. HEPA air filter (image) (United States)

    ... pet dander and other irritating allergens from the air. Along with other methods to reduce allergens, such ... controlling the amount of allergens circulating in the air. HEPA filters can be found in most air ...

  8. GSPEL - Air Filtration Laboratory (United States)

    Federal Laboratory Consortium — Evaluation capabilities for air filtration devicesThe Air Filtration Lab provides testing of air filtration devices to demonstrate and validate new or legacy system...

  9. Lead (Pb) Air Pollution (United States)

    ... States Environmental Protection Agency Search Search Lead (Pb) Air Pollution Share Facebook Twitter Google+ Pinterest Contact Us As ... and protect aquatic and terrestrial ecosystems. Lead (Pb) Air Pollution Lead Air Pollution Basics How does lead get ...

  10. AirPEx: Air Pollution Exposure Model


    Freijer JI; Bloemen HJTh; de Loos S; Marra M; Rombout PJA; Steentjes GM; Veen MP van; LBO


    Analysis of inhalatory exposure to air pollution is an important area of investigation when assessing the risks of air pollution for human health. Inhalatory exposure research focuses on the exposure of humans to air pollutants and the entry of these pollutants into the human respiratory tract. The principal grounds for studying the inhalatory exposure of humans to air pollutants are formed by the need for realistic exposure/dose estimates to evaluate the health effects of these pollutants. T...

  11. Near-edge X-ray absorption fine structure spectroscopy-assisted purification of single-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Yan Dongwei [Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China); Zhong Jun [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Wang Chunru [Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China)], E-mail:; Wu Ziyu [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)], E-mail:


    Single-walled carbon nanotubes were produced by the conventional arc discharge method, and purified with a two-step treatment. First, the raw soot containing single-walled carbon nanotubes was burned up at ca. 350 deg. C in air to remove amorphous carbon, and then it was treated by strong acidic solvents to remove metal catalysts. Near-edge X-ray absorption fine structure spectroscopy was applied to analyze the defects on single-walled carbon nanotubes in whole purification process, so the experimental conditions can be optimized, and finally high-purity single-walled carbon nanotubes were obtained as revealed by various spectroscopic characterizations such as scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, and Raman spectroscopy.

  12. Advanced purification strategy for CueR, a cysteine containing copper(I) and DNA binding protein

    DEFF Research Database (Denmark)

    Balogh, Ria K.; Gyurcsik, Béla; Hunyadi-Gulyás, Éva


    . A detailed understanding of their function may be exploited in potential health, environmental and analytical applications. Members of the MerR protein family sense a broad range of mostly late transition and heavy metal ions through their cysteine thiolates. The air sensitivity of latter groups makes......Metal ion regulation is essential for living organisms. In prokaryotes metal ion dependent transcriptional factors, the so-called metalloregulatory proteins play a fundamental role in controlling the concentration of metal ions. These proteins recognize metal ions with an outstanding selectivity...... any affinity tag. Structure and functionality tests performed with mass spectrometry, circular dichroism spectroscopy and electrophoretic gel mobility shift assays approved the success of the purification procedure....

  13. AirPEx: Air Pollution Exposure Model

    NARCIS (Netherlands)

    Freijer JI; Bloemen HJTh; Loos S de; Marra M; Rombout PJA; Steentjes GM; Veen MP van; LBO


    Analysis of inhalatory exposure to air pollution is an important area of investigation when assessing the risks of air pollution for human health. Inhalatory exposure research focuses on the exposure of humans to air pollutants and the entry of these pollutants into the human respiratory tract. The

  14. Air Pollution Monitoring | Air Quality Planning & Standards ... (United States)


    The basic mission of the Office of Air Quality Planning and Standards is to preserve and improve the quality of our nation's air. To accomplish this, OAQPS must be able to evaluate the status of the atmosphere as compared to clean air standards and historical information.

  15. Pseudobrookite-type MgTi2O5 water purification filter with controlled particle morphology

    Directory of Open Access Journals (Sweden)

    Yuta Nakagoshi


    Full Text Available Pseudobrookite-type oxide-based ceramics, such as Al2TiO5 and MgTi2O5, have recently been studied as porous ceramic membranes. Here, the effect of LiF doping on the morphology of MgTi2O5 particles is presented in detail. Water purification filters were produced using porous MgTi2O5, with different particle morphologies. MgCO3 (basic and TiO2 powders with various LiF contents were wet-ball milled, dried, and then, calcined in air at 1100 °C to obtain the MgTi2O5 powders. The powder compacts were sintered at 1000–1200 °C to produce the MgTi2O5 disk filters. The 0.5 wt.% LiF-doped MgTi2O5 disk filter, with elongated grains, showed well-balanced performance removing boehmite particles with diameter of 0.7 μm. Non-doped MgTi2O5 disk filter with equiaxed grains was suitable for precise filtration.

  16. Efficient biotinylation and single-step purification of tagged transcription factors in mammalian cells and transgenic mice.

    NARCIS (Netherlands)

    E. de Boer (Ernie); P. Rodriguez (Patrick); E. Bonte (Edgar); J. Krijgsveld (Jeroen); E. Katsantoni (Eleni); A.J.R. Heck (Albert); F.G. Grosveld (Frank); J. Strouboulis (John)


    textabstractProteomic approaches require simple and efficient protein purification methodologies that are amenable to high throughput. Biotinylation is an attractive approach for protein complex purification due to the very high affinity of avidin/streptavidin for biotinylated temp

  17. 家用空气净化器净化技术的探讨%Discussion on Technology of Domestic Air Purifier

    Institute of Scientific and Technical Information of China (English)



    研究表明,室内空气的污染程度远超室外数倍,室内空气污染已成为人类生活中的主要健康威胁,人们急需空气净化技术对室内空气进行防护,具有滤除各种有害气体的新型家用电器---空气净化器应运而生,本文从过滤原理、净化技术、检测方法以及发展趋势四个方面进行讨论分析,为今后我国空气净化技术的长远发展提供参考。%Researches suggest that indoor air pollution is larger than outdoor's. Indoor air pollution has become a major health threat in human life, so people need air purification technology for indoor air protection. As a new type of home appliances, air purifier has come true. In this paper, filtration theory, purification technology, test method and development tendency are discussed. It is a reference for the future air purification technology.

  18. REACH. Air Conditioning Units. (United States)

    Garrison, Joe; And Others

    As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of air conditioning. The instructional units focus on air conditioning fundamentals, window air conditioning, system and installation, troubleshooting and…

  19. Statistical air quality mapping

    NARCIS (Netherlands)

    Kassteele, van de J.


    This thesis handles statistical mapping of air quality data. Policy makers require more and more detailed air quality information to take measures to improve air quality. Besides, researchers need detailed air quality information to assess health effects. Accurate and spatially highly resolved maps

  20. Fundamental mechanisms in Li-air battery electrochemistry

    DEFF Research Database (Denmark)

    Højberg, Jonathan

    The lithium-air (or Li-O2) batteries have received wide attention as an enabling technology for a mass market entry of electric vehicles due to a potential capacity much higher than current Li-ion technology. The technology is a relatively new battery concept proposed in 1996, and the current...... was used to characterize our carbon-based reference system as well as new ionic liquid-based electrolytes. Electrochemical impedance spectroscopy (EIS) has been used extensively to describe reaction mechanisms inside the battery; the origin of the measured overpotentials; and the onset potential...... battery system better than any other method available. Finally, calculations were made to support that an open system configuration is a realistic option in terms of air purification, if H2O and CO2 levels at 1 ppm are allowed....

  1. Synthesis of medronic acid monoesters and their purification by high-performance countercurrent chromatography or by hydroxyapatite


    Elina Puljula; Jouko Vepsäläinen; Petri A. Turhanen


    We achieved the synthesis of important medronic acid monoalkyl esters via the dealkylation of mixed trimethyl monoalkyl esters of medronic acid. Two methods were developed for the purification of medronic acid monoesters: 1) small scale (10–20 mg) purification by using hydroxyapatite and 2) large scale (tested up to 140 mg) purification by high-performance countercurrent chromatography (HPCCC).

  2. Synthesis of medronic acid monoesters and their purification by high-performance countercurrent chromatography or by hydroxyapatite

    Directory of Open Access Journals (Sweden)

    Elina Puljula


    Full Text Available We achieved the synthesis of important medronic acid monoalkyl esters via the dealkylation of mixed trimethyl monoalkyl esters of medronic acid. Two methods were developed for the purification of medronic acid monoesters: 1 small scale (10–20 mg purification by using hydroxyapatite and 2 large scale (tested up to 140 mg purification by high-performance countercurrent chromatography (HPCCC.

  3. Development of an automated system for isolation and purification of humic substances

    NARCIS (Netherlands)

    Zomeren, van A.; Weij-Zuiver, van der E.; Comans, R.N.J.


    Characterization of humic substances (HS) in environmental samples generally involves labor-intensive and time-consuming isolation and purification procedures. In this paper, the development of an automated system for HS isolation and purification is described. The novelty of the developed system li

  4. Tandem affinity purification of functional TAP-tagged proteins from human cells

    NARCIS (Netherlands)

    Gregan, Juraj; Riedel, Christian G; Petronczki, Mark; Cipak, Lubos; Rumpf, Cornelia; Poser, Ina; Buchholz, Frank; Mechtler, Karl; Nasmyth, Kim


    Tandem affinity purification (TAP) is a generic two-step affinity purification protocol for isolation of TAP-tagged proteins together with associated proteins. We used bacterial artificial chromosome to heterologously express TAP-tagged murine Sgo1 protein in human HeLa cells. This allowed us to tes

  5. Purification of heat labile toxin from Bordetella pertussis vaccine strain 134 employed indigenous technology

    Directory of Open Access Journals (Sweden)

    K.C. Shivanandappa


    Conclusion: The B. pertussis HLT could be purified through two phase with G50 and DEAE, cost effective techniques, the G50 purification has reduced the bioburden problems during DEAE purification and at the same time the quality of the product was high.

  6. Using an FPLC to Promote Active Learning of the Principles of Protein Structure and Purification (United States)

    Robinson, Rebekah L.; Neely, Amy E.; Mojadedi, Wais; Threatt, Katie N.; Davis, Nicole Y.; Weiland, Mitch H.


    The concepts of protein purification are often taught in undergraduate biology and biochemistry lectures and reinforced during laboratory exercises; however, very few reported activities allow students to directly gain experience using modern protein purification instruments, such as Fast Protein Liquid Chromatography (FPLC). This laboratory…

  7. A Versatile and Inexpensive Enzyme Purification Experiment for Undergraduate Biochemistry Labs. (United States)

    Farrell, Shawn O.; Choo, Darryl


    Develops an experiment that could be done in two- to three-hour blocks and does not rely on cold room procedures for most of the purification. Describes the materials, methods, and results of the purification of bovine heart lactate dehydrogenase using ammonium sulfate fractionation, dialysis, and separation using affinity chromatography and…

  8. 24 CFR 203.52 - Acceptance of individual residential water purification equipment. (United States)


    ... residential water purification equipment. 203.52 Section 203.52 Housing and Urban Development Regulations... water purification equipment. If a property otherwise eligible for insurance under this part does not have access to a continuing supply of safe and potable water without the use of a water...

  9. Entanglement purification with noisy apparatus can be used to factor out an eavesdropper



    We give a proof that entanglement purification, even with noisy apparatus, is sufficient to disentangle an eavesdropper (Eve) from the communication channel. Our proof applies to all possible attacks (individual and coherent). Due to the quantum nature of the entanglement purification protocol, it is also possible to use the obtained quantum channel for secure transmission of quantum information.

  10. A Comparative Study of Observed Score Approaches and Purification Procedures for Detecting Differential Item Functioning. (United States)

    Kwak, Nohoon; Davenport, Ernest C., Jr.; Davison, Mark L.

    The purposes of this study were to introduce the iterative purification procedure and to compare this with the two-step purification procedure, to compare false positive error rates and the power of five observed score approaches and to identify factors affecting power and false positive rates in each method. This study used 2,400 data sets that…

  11. Genome-wide Purification of Extrachromosomal Circular DNA from Eukaryotic Cells

    DEFF Research Database (Denmark)

    Møller, Henrik D.; Bojsen, Rasmus Kenneth; Tachibana, Chris;


    for detecting eccDNA are needed to clarify how these elements affect genome stability and how environmental and biological factors induce their formation in eukaryotic cells. This video presents a sensitive eccDNA-purification method called Circle-Seq. The method encompasses column purification of circular DNA...


    NARCIS (Netherlands)



    When membrane proteins are solubilized and subjected to purification procedures, the loss of lipids surrounding the protein often results in irreversible inactivation. We describe a procedure for the immunoaffinity purification of the membrane protein UDP-glucuronosyltransferase from human liver. Th

  13. A novel purification method for histidine-tagged proteins containing a thrombin cleavage site

    NARCIS (Netherlands)

    Hefti, M.H.; Vugt-Toorn, van der C.J.; Dixon, R.; Vervoort, J.J.M.


    A general procedure for the purification of histidine-tagged proteins has been developed using immobilized metal-ion affinity chromatography. This two-step purification method can be used for proteins containing a hexahistidine tag and a thrombin cleavage site, yielding high amounts of purified prot

  14. Item Purification Does Not Always Improve DIF Detection: A Counterexample with Angoff's Delta Plot (United States)

    Magis, David; Facon, Bruno


    Item purification is an iterative process that is often advocated as improving the identification of items affected by differential item functioning (DIF). With test-score-based DIF detection methods, item purification iteratively removes the items currently flagged as DIF from the test scores to get purified sets of items, unaffected by DIF. The…

  15. Method for Rapid Purification of Class IIa Bacteriocins and Comparison of Their Activities


    Guyonnet, D.; Fremaux, C; Cenatiempo, Y; Berjeaud, J. M.


    A three-step method was developed for the purification of mesentericin Y105 (60% yield) from the culture supernatant of Leuconostoc mesenteroides Y105. The same procedure was successfully applied to the purification of five other anti-Listeria bacteriocins identified by mass spectrometry. Specific activities of the purified bacteriocins were compared.

  16. Purification of a Recombinant Glutathione Transferase from the Causative Agent of Hydatidosis, "Echinococcus granulosus" (United States)

    Fleitas, Andrea L.; Randall, Lía M.; Möller, Matías N.; Denicola, Ana


    This practical class activity was designed to introduce students to recombinant protein expression and purification. The principal goal is to shed light on basic aspects concerning recombinant protein production, in particular protein expression, chromatography methods for protein purification, and enzyme activity as a tool to evaluate purity and…

  17. Air movement and perceived air quality

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Kaczmarczyk, J.


    The impact of air movement on perceived air quality (PAQ) and sick building syndrome (SBS) symptoms was studied. In total, 124 human subjects participated in four series of experiments performed in climate chambers at different combinations of room air temperature (20, 23, 26 and 28 °C), relative...... and the humidity of the room air. At a low humidity level of 30% an increased velocity could compensate for the decrease in perceived air quality due to an elevated temperature ranging from 20 °C to 26 °C. In a room with 26 °C, increased air movement was also able to compensate for an increase in humidity from 30...

  18. Magnetic purification of curcumin from Curcuma longa rhizome by novel naked maghemite nanoparticles. (United States)

    Magro, Massimiliano; Campos, Rene; Baratella, Davide; Ferreira, Maria Izabela; Bonaiuto, Emanuela; Corraducci, Vittorino; Uliana, Maíra Rodrigues; Lima, Giuseppina Pace Pereira; Santagata, Silvia; Sambo, Paolo; Vianello, Fabio


    Naked maghemite nanoparticles, namely, surface active maghemite nanoparticles (SAMNs), characterized by a diameter of about 10 nm, possessing peculiar colloidal stability, surface chemistry, and superparamagnetism, present fundamental requisites for the development of effective magnetic purification processes for biomolecules in complex matrices. Polyphenolic molecules presenting functionalities with different proclivities toward iron chelation were studied as probes for testing SAMN suitability for magnetic purification. Thus, the binding efficiency and reversibility on SAMNs of phenolic compounds of interest in the pharmaceutical and food industries, namely, catechin, tyrosine, hydroxytyrosine, ferulic acid, coumaric acid, rosmarinic acid, naringenin, curcumin, and cyanidin-3-glucoside, were evaluated. Curcumin emerged as an elective compound, suitable for magnetic purification by SAMNs from complex matrices. A combination of curcumin, demethoxycurcumin, and bis-demethoxycurcumin was recovered by a single magnetic purification step from extracts of Curcuma longa rhizomes, with a purity >98% and a purification yield of 45%, curcumin being >80% of the total purified curcuminoids.

  19. Experimental optimal single qubit purification in an NMR quantum information processor. (United States)

    Hou, Shi-Yao; Sheng, Yu-Bo; Feng, Guan-Ru; Long, Gui-Lu


    High quality single qubits are the building blocks in quantum information processing. But they are vulnerable to environmental noise. To overcome noise, purification techniques, which generate qubits with higher purities from qubits with lower purities, have been proposed. Purifications have attracted much interest and been widely studied. However, the full experimental demonstration of an optimal single qubit purification protocol proposed by Cirac, Ekert and Macchiavello [Phys. Rev. Lett. 82, 4344 (1999), the CEM protocol] more than one and half decades ago, still remains an experimental challenge, as it requires more complicated networks and a higher level of precision controls. In this work, we design an experiment scheme that realizes the CEM protocol with explicit symmetrization of the wave functions. The purification scheme was successfully implemented in a nuclear magnetic resonance quantum information processor. The experiment fully demonstrated the purification protocol, and showed that it is an effective way of protecting qubits against errors and decoherence.

  20. Tall fescue seed extraction and partial purification of ergot alkaloids. (United States)

    Ji, Huihua; Fannin, F; Klotz, J; Bush, Lowell


    Many substances in the tall fescue/endophyte association (Schedonorus arundinaceus/Epichloë coenophiala) have biological activity. Of these compounds only the ergot alkaloids are known to have significant mammalian toxicity and the predominant ergot alkaloids are ergovaline and ergovalinine. Because synthetically produced ergovaline is difficult to obtain, we developed a seed extraction and partial purification protocol for ergovaline/ergovalinine that provided a biologically active product. Tall fescue seed was ground and packed into several different sized columns for liquid extraction. Smaller particle size and increased extraction time increased efficiency of extraction. Our largest column was a 114 × 52 × 61 cm (W × L × D) stainless steel tub. Approximately 150 kg of seed could be extracted in this tub. The extraction was done with 80% ethanol. When the solvent front migrated to bottom of the column, flow was stopped and seed was allowed to steep for at least 48 h. Light was excluded from the solvent from the beginning of this step to the end of the purification process. Following elution, ethanol was removed from the eluate by evaporation at room temperature and the resulting syrup was freeze-dried. About 80% recovery of alkaloids was achieved with 18-fold increase in concentration of ergovaline. Initial purification of the dried product was accomplished by extracting with hexane/water (6:1, v/v). The aqueous fraction was extracted with chloroform, the aqueous layer discarded, after which the chloroform was removed with a resulting 20-fold increase of ergovaline. About 65% of the ergovaline was recovered from the chloroform residue for an overall recovery of 50%. The resultant partially purified ergovaline had biological activities in in vivo and in vitro bovine bioassays that approximate that of synthetic ergovaline.

  1. Tall fescue seed extraction and partial purification of ergot alkaloids (United States)

    Bush, Lowell


    Many substances in the tall fescue/endophyte association (Schedonorus arundinaceus/Epichloë coenophiala) have biological activity. Of these compounds only the ergot alkaloids are known to have significant mammalian toxicity and the predominant ergot alkaloids are ergovaline and ergovalinine. Because synthetically produced ergovaline is difficult to obtain, we developed a seed extraction and partial purification protocol for ergovaline/ergovalinine that provided a biologically active product. Tall fescue seed was ground and packed into several different sized columns for liquid extraction. Smaller particle size and increased extraction time increased efficiency of extraction. Our largest column was a 114 × 52 × 61 cm (W×L×D) stainless steel tub. Approximately 150 kg of seed could be extracted in this tub. The extraction was done with 80% ethanol. When the solvent front migrated to bottom of the column, flow was stopped and seed was allowed to steep for at least 48 h. Light was excluded from the solvent from the beginning of this step to the end of the purification process. Following elution, ethanol was removed from the eluate by evaporation at room temperature. Resulting syrup was freeze-dried. About 80% recovery of alkaloids was achieved with 18-fold increase in concentration of ergovaline. Initial purification of the dried product was accomplished by extracting with hexane/water (6:1, v/v) and the hexane fraction was discarded. The aqueous fraction was extracted with chloroform, the aqueous layer discarded, after which the chloroform was removed with a resulting 20-fold increase of ergovaline. About 65% of the ergovaline was recovered from the chloroform residue for an overall recovery of 50%. The resultant partially purified ergovaline had biological activities in in vivo and in vitro bovine bioassays that approximate that of synthetic ergovaline.

  2. Fractionation for Biodiesel Purification Using Supercritical Carbon Dioxide

    Directory of Open Access Journals (Sweden)

    Chao-Yi Wei


    Full Text Available In recent years, biodegradable and alternative biodiesel has attracted increased attention worldwide. Producing biodiesel from biomass involves critical separation and purification technology. Conventional technologies such as gravitational settling, decantation, filtration, water washing, acid washing, organic solvent washing and absorbent applications are inefficient, less cost effective and environmentally less friendly. In this study supercritical carbon dioxide (SC-CO2 with few steps and a low environmental impact, was used for biodiesel fractionation from impure fatty acid methyl ester (FAME solution mixes. The method is suitable for application in a variety of biodiesel production processes requiring subsequent stages of purification. The fractionation and purification was carried out using continuous SC-CO2 fractionation equipment, consisting of three columns filled with stainless steel fragments. A 41.85% FAME content solution mix was used as the raw material in this study. Variables were a temperature range of 40–70 °C, pressure range of 10–30 MPa, SC-CO2 flow rate range of 7–21 mL/min and a retention time range of 30–90 min. The Taguchi method was used to identify optimal operating conditions. The results show that a separated FAME content of 99.94% was verified by GC-FID under optimal fractionation conditions, which are a temperature of 40 °C of, a pressure level of 30MPa and a flow rate of 7 mL/min of SC-CO2 for a retention time of 90 min.

  3. Anion exchange purification of plasmid DNA using expanded bed adsorption. (United States)

    Ferreira, G N; Cabral, J M; Prazeres, D M


    Recent developments in gene therapy with non-viral vectors and DNA vaccination have increased the demand for large amounts of pharmaceutical-grade plasmid DNA. The high viscosity of process streams is of major concern in the purification of plasmids, since it can cause high back pressures in column operations, thus limiting the throughput. In order to avoid these high back pressures, expanded bed anion exchange chromatography was evaluated as an alternative to fixed bed chromatography. A Streamline 25 column filled with 100 ml of Streamline QXL media, was equilibrated with 0.5 M NaCl in TE (10 mM Tris, 1 mM EDTA, pH = 8.0) buffer at an upward flow of 300 cmh-1, E. coli lysates (obtained from up to 3 liters of fermentation broth) were injected in the column. After washing out the unbound material, the media was allowed to sediment and the plasmid was eluted with 1 M NaCl in TE buffer at a downward flow of 120 cmh-1. Purification factors of 36 +/- 1 fold, 26 +/- 0.4 plasmid purity, and close to 100% yields were obtained when less than one settled column volume of plasmid feed was injected. However, both recovery yield and purity abruptly decreased when larger amounts were processed-values of 35 +/- 2 and 5 +/- 0.7 were obtained for the recovery yield and purity, respectively, when 250 ml of feedstock were processed. In these cases, gel clogging and expansion collapse were observed. The processing of larger volumes, thus larger plasmid quantities, was only possible by performing an isopropanol precipitation step prior to the chromatographic step. This step led to an enhancement of the purification step.

  4. Fermentation, fractionation and purification of streptokinase by chemical reduction method

    Directory of Open Access Journals (Sweden)

    M Niakan


    Full Text Available Background and Objectives: Streptokinase is used clinically as an intravenous thrombolytic agent for the treatment of acute myocardial infarction and is commonly prepared from cultures of Streptococcus equisimilis strain H46A. The objective of the present study was the production of streptokinase from strain H46A and purification by chemical reduction method."nMaterials and Methods: The rate of streptokinase production evaluated under the effect of changes on some fermentation factors. Moreover, due to the specific structure of streptokinase, a chemical reduction method employed for the purification of streptokinase from the fermentation broth. The H46A strain of group C streptococcus, was grown in a fermentor. The proper pH adjusted with NaOH under glucose feeding in an optimum temperature. The supernatant of the fermentation product was sterilized by filtration and concentrated by ultrafiltration. The pH of the concentrate was adjusted, cooled, and precipitated by methanol. Protein solution was reduced with dithiothreitol (DTT. Impurities settled down by aldrithiol-2 and the biological activity of supernatant containing streptokinase was determined."nResults: In the fed -batch culture, the rate of streptokinase production increased over two times as compared with the batch culture and the impurities were effectively separated from streptokinase by reduction method."nConclusion: Improvements in SK production are due to a decrease in lag phase period and increase in the growth rate of logarithmic phase. The methods of purification often result in unacceptable losses of streptokinase, but the chemical reduction method give high yield of streptokinase and is easy to perform it.

  5. Tall fescue seed extraction and partial purification of ergot alkaloids

    Directory of Open Access Journals (Sweden)

    Lowell eBush


    Full Text Available Many substances in the tall fescue/endophyte association (Schedonorus arundinaceus/Epichloë coenophiala have biological activity. Of these compounds only the ergot alkaloids are known to have significant mammalian toxicity and the predominant ergot alkaloids are ergovaline and ergovalinine. Because synthetically produced ergovaline is difficult to obtain, we developed a seed extraction and partial purification protocol for ergovaline/ergovalinine that provided a biologically active product. Tall fescue seed was ground and packed into several different sized columns for liquid extraction. Smaller particle size and increased extraction time increased efficiency of extraction. Our largest column was a 114 × 52 × 61 cm (W×L×D stainless steel tub. Approximately 150 kg of seed could be extracted in this tub. The extraction was done with 80% ethanol. When the solvent front migrated to bottom of the column, flow was stopped and seed was allowed to steep for at least 48 h. Light was excluded from the solvent from the beginning of this step to the end of the purification process. Following elution, ethanol was removed from the eluate by evaporation at room temperature. Resulting syrup was freeze-dried. About 80% recovery of alkaloids was achieved with 18-fold increase in concentration of ergovaline. Initial purification of the dried product was accomplished by extracting with hexane/water (6:1, v/v and the hexane fraction was discarded. The aqueous fraction was extracted with chloroform, the aqueous layer discarded, after which the chloroform was removed with a resulting 20-fold increase of ergovaline. About 65% of the ergovaline was recovered from the chloroform residue for an overall recovery of 50%. The resultant partially purified ergovaline had biological activities in in vivo and in vitro bovine bioassays that approximate that of synthetic ergovaline.

  6. Magnetic DNA affinity purification of yeast transcription factor tau--a new purification principle for the ultrarapid isolation of near homogeneous factor.



    We present a new method for rapid purification to near homogeneity of sequence specific DNA binding proteins based on magnetic separation. The method is described for the purification of the yeast transcription factor tau. DNA affinity Dynabeads (monodisperse superparamagnetic particles) specifically bind the protein in the presence of competitor DNA. By magnetic separation, wash and elution, highly enriched transcription factor preparations are obtained within minutes. In less than an hour w...

  7. Expression, purification and characterization of human Dopamine ß-monooxygenase

    DEFF Research Database (Denmark)

    Vendelboe, Trine Vammen

    This thesis deals with expression, purification and characterization of the copper containing enzyme dopamine ß-monooxygenase (DBM). DBM is an ascorbate dependent protein that requires Cu in the active site in order to be functional. DBM is made of four domains; An Nterminal DOMON domain, the two...... others, one of the reasons why these proteins are considered to follow the same mechanism. DBM converts dopamine (DA) into Norepinphrine (NE). Both substrate and product functions as neurotransmitters and the levels of these are involved in many different disorders such as depression and hypertension...

  8. Exploiting interfacial water properties for desalination and purification applications.

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Hongwu (Los Alamos National Laboratory, Los Alamos, NM); Varma, Sameer; Nyman, May Devan; Alam, Todd Michael; Thuermer, Konrad; Holland, Gregory P.; Leung, Kevin; Liu, Nanguo (University of New Mexico Albuquerque, NM); Xomeritakis, George K. (University of New Mexico Albuquerque, NM); Frankamp, Benjamin L.; Siepmann, J. Ilja (University of Minnesota, Minneapolis, MN); Cygan, Randall Timothy; Hartl, Monika A. (Los Alamos National Laboratory, Los Alamos, NM); Travesset, Alex (Iowa State University, Ames, IA); Anderson, Joshua A. (Iowa State University, Ames, IA); Huber, Dale L.; Kissel, David J. (University of New Mexico Albuquerque, NM); Bunker, Bruce Conrad; Lorenz, Christian Douglas; Major, Ryan C. (University of Minnesota, Minneapolis, MN); McGrath, Matthew J. (University of Minnesota, Minneapolis, MN); Farrow, Darcie; Cecchi, Joseph L. (University of New Mexico Albuquerque, NM); van Swol, Frank B.; Singh, Seema; Rempe, Susan B.; Brinker, C. Jeffrey; Clawson, Jacalyn S.; Feibelman, Peter Julian; Houston, Jack E.; Crozier, Paul Stewart; Criscenti, Louise Jacqueline; Chen, Zhu (University of New Mexico Albuquerque, NM); Zhu, Xiaoyang (University of Minnesota, Minneapolis, MN); Dunphy, Darren Robert (University of New Mexico Albuquerque, NM); Orendorff, Christopher J.; Pless, Jason D.; Daemen, Luke L. (Los Alamos National Laboratory, Los Alamos, NM); Gerung, Henry (University of New Mexico Albuquerque, NM); Ockwig, Nathan W.; Nenoff, Tina Maria; Jiang, Ying-Bing; Stevens, Mark Jackson


    A molecular-scale interpretation of interfacial processes is often downplayed in the analysis of traditional water treatment methods. However, such an approach is critical for the development of enhanced performance in traditional desalination and water treatments. Water confined between surfaces, within channels, or in pores is ubiquitous in technology and nature. Its physical and chemical properties in such environments are unpredictably different from bulk water. As a result, advances in water desalination and purification methods may be accomplished through an improved analysis of water behavior in these challenging environments using state-of-the-art microscopy, spectroscopy, experimental, and computational methods.

  9. Molecular Techniques for Dicistrovirus Detection without RNA Extraction or Purification

    Directory of Open Access Journals (Sweden)

    Jailson F. B. Querido


    Full Text Available Dicistroviridae is a new family of small, nonenveloped, and +ssRNA viruses pathogenic to both beneficial arthropods and insect pests as well. Triatoma virus (TrV, a dicistrovirus, is a pathogen of Triatoma infestans (Hemiptera: Reduviidae, one of the main vectors of Chagas disease. In this work, we report a single-step method to identify TrV, a dicistrovirus, isolated from fecal samples of triatomines. The identification method proved to be quite sensitive, even without the extraction and purification of RNA virus.

  10. Preparation and Characterization of Zeolite Membrane for Bioethanol Purification

    Directory of Open Access Journals (Sweden)

    Aprilina Purbasari


    Full Text Available The use of bioethanol as an alternative fuel with a purity of more than 99.5% wt has prompted research on bioethanol purification. One of the promising methods used for bioethanol purification is pervaporation membrane. This research is aimed to prepare and characterize zeolite membranes for pervaporation membrane. The membrane preparation consisted of two stages, namely support preparation and zeolite deposition on the support. In support preparation, α- alumina and kaolin with specific composition (50:30; 40:40; 50:30 was mixed with additives and water. After pugging and aging process, the mixture became paste and extruded into tubular shape. The tube was then calcined at temperature of 1250 °C for 3 hours. After that, zeolite 4A was deposited on the tubes using clear solution made of 10 %wt zeolite and 90 %wt water and heated at temperature of 80 °C for 3 hours. Furthermore, the resulting zeolite membranes was washed with deionized water for 5 minutes and dried in oven at temperature of 100 °C for 24 hours. Characterization of zeolite membranes included mechanical strength test, XRD, and SEM. In the mechanical strength test, the membrane sample with α- alumina:kaolin = 50:30 (membrane A has the highest mechanical strength of 46.65 N/mm2. Result of XRD analysis for the membrane A indicated that mullite and corundum phases were formed, which mullite phase was more dominant. Meanwhile the result of SEM analysis shows that zeolite crystals have been formed and covered the pores support, but the deposition of zeolite has not been optimal yet. The performance examination for bioethanol purification showed that the membrane could increase the purity of bioethanol from 95% to 98.5% wt. © 2013 BCREC UNDIP. All rights reservedReceived: 23rd October 2012; Revised: 15th February 2013; Accepted: 16th February 2013[How to Cite: Purbasari, A., Istirokhatun, T., Devi, A.M., Mahsunnah, L. , Susanto, H. (2013. Preparation and Characterization of Zeolite

  11. Process for the biological purification of waste water

    DEFF Research Database (Denmark)


    Process for the biological purification of waste water by the activated sludge method, the waste water being mixed with recirculated sludge and being subjected to an anaerobic treatment, before the waste water thus treated is alternately subjected to anoxic and aerobic treatments and the waste...... water thus treated is led into a clarification zone for settling sludge, which sludge is recirculated in order to be mixed with the crude waste water. As a result, a simultaneous reduction of the content both of nitrogen and phosphorus of the waste water is achieved....

  12. Isolation and Preparative Purification for Ginkgolides A and B

    Institute of Scientific and Technical Information of China (English)

    韩金玉; 王华; 常贺英; 褚巧伟


    In this paper a simple preparative method for isolation and purification of ginkgolides A and B was developed,As starting material,a commercially available standardized ginkgo extract (EGb761,containing 24% flavonoid and 6% terpene trilactones) was used,After a pretreatment step,optimized by the uniform design method ,the concentrated intermediate extract with high content of GA and gb(+90%) was separated into the individual terpenes by preparative liquid chromatography eluted with petroleum ether-ethylacetate,Analysis of products was carried out by means of HPLC-ELSD(evaporative light -scattering detector),The results show that ginkgolides A and B are obtained in higher yield and better purity.

  13. Palladium-based Membrane Applications for Hydrogen Purification

    Institute of Scientific and Technical Information of China (English)

    LI Yin'e; MA Guang; JIA Zhihua; JIANG Ting


    It describes the purification of hydrogen isotopes,separation with the preparation of palladium-based membrane's technology,types,application,advantages and disadvantages of palladium in this article.Due to excellent comprehensive properties palladium composite membrane will become the future direction of development.At the same time it will develop preparation methods of the membrane support body with high mechanical strength and heat resistance and low-cost and palladium-based membrane.Also it will explore high service life and high transmittance of novel composite membrane.

  14. Expression, purification and preliminary diffraction studies of PhnP

    DEFF Research Database (Denmark)

    Podzelinska, Kateryna; He, Shumei; Soares, Alexei;


    PhnP belongs to a 14-gene operon that supports the growth of Escherichia coli on alkylphosphonates as a sole source of phosphorus; however, the exact biochemistry of phosphonate degradation by this pathway is poorly understood. The protein was recombinantly expressed in Escherichia coli and purif......PhnP belongs to a 14-gene operon that supports the growth of Escherichia coli on alkylphosphonates as a sole source of phosphorus; however, the exact biochemistry of phosphonate degradation by this pathway is poorly understood. The protein was recombinantly expressed in Escherichia coli...


    Institute of Scientific and Technical Information of China (English)



    This paper summarizes the results of separation and purification of 234Th from aged uranium salt with two processes(see flowsheet A or B).The flowsheet.A:TBP extraction,anion exchange and TTA extraction;the flowsheetB:Cation and anion exchange,TTA extraction.The total recovery efficiency of 234Th is about 90%.The γ-spectrum of the end-product contains only two typic peaks of 234Th(63and 92keV).Pure 234Th is prepared.

  16. Novel Hydrogen Purification Device Integrated with PEM Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Joseph Schwartz; Hankwon Lim; Raymond Drnevich


    A prototype device containing twelve membrane tubes was designed, built, and demonstrated. The device produced almost 300 scfh of purified hydrogen at 200 psig feed pressure. The extent of purification met the program target of selectively removing enough impurities to enable industrial-grade hydrogen to meet purity specifications for PEM fuel cells. An extrusion process was developed to produce substrate tubes. Membranes met several test objectives, including completing 20 thermal cycles, exceeding 250 hours of operating life, and demonstrating a flux of 965 scfh/ft2 at 200 psid and 400 C.

  17. Purification and Properties of Clostridium perfringens Spore Lytic Enzymes. (United States)


    sacs was effective. Further purification was obtained using carboxymethylcellulose and Sephadex G-100 chromatography. At this point the purified produce...Concentrated culture supernatant fluid (CSF) containing the initiation protein (IP) was prepared from 7 h cultures of C perfringens NCTC 8798 grown in DS...four different methods (a) 0.05 M DTT, (b) 0.05 M DTT plus 0.5% (w/v) SDS, both prepared in 0.05 M glycine-NaOH buffer, with the pH adjusted to 10.0

  18. Treatment for purification water of biodiesel using electrofloculation

    Directory of Open Access Journals (Sweden)

    Juliana Ferreira de Brito


    Full Text Available Biodiesel was created as a solution for a great economic and enviromental problem of petroleum, a resource with sustainable characteristics. But its production still needs optimization, because it uses a lot of water and generates a large volume of this residue, which appears improper to disposal without correct treatment. This work propose an economic, viable and efficient way to treat the Biodiesel purification water, not only aiming at a proper disposal, but the reuse as input in the process, generating a large industrial economy, and greater environmental progress. For both treatment uses the electrofloculation technique.

  19. Preparation and purification of 7-Iodoclonazepam for use in radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Goddard, C.P.; Law, B.; Mason, P.A.; Stead, A.H.


    A method is described for the preparation and purification of 7-(/sup 125/I)-Iodoclonazepam (5-(o-Chlorophenyl)-2,3-Dihydro-7-(/sup 125/I)-Iodo-1H-1,4-Benzodiazepin-2-one). The structure was confirmed by mass spectrometry using 7-(/sup 127/I)iodoclonazepam prepared by the same method. 7-(/sup 125/I)-Iodoclonazepam binds well to a benzodiazepine antiserum. Although readily displaced by all the benzodiazepines commercially available in the UK, it is not displaced by structurally related nonbenzodiazepines except at very high concentrations. 7-(/sup 125/I) Iodoclonazepam should therefore be useful for the development of a screening radioimmunoassay (RIA) for benzodiazepines.

  20. Organic-inorganic hybrid materials in separation chemistry: a molecular approach towards design of purification processes; De la molecule au procede. Apports des materiaux hybrides organiques-inorganiques en chimie separative

    Energy Technology Data Exchange (ETDEWEB)

    Brandes, St.; Denat, F. [Centre National de la Recherche Scientifique (CNRS), 21 - Dijon (France); Meyer, M.; Guilard, R. [Universite de Bourgogne, Lab. d' Ingenierie Moleculaire pour la Separation et les Applications des Gaz (LIMSAG) UMR 5633 du CNRS, 21 - Dijon (France)


    Located on the campus of the Universite de Bourgogne and supported by the CNRS, the main particularity of the LIMSAG was its association with an industrial partner, the Air Liquide company. The main objectives of this unusual research unit in the French academic system was to conceive and develop new molecules and materials that exhibit suitable properties for the ultra-purification or the detection of gases. Beside these activities, a second research topic is dedicated to the decontamination of industrial waste streams containing either toxic (lead, cadmium) and/or radioactive metal ions (uranium, plutonium, americium). Specific sequestering agents have also been designed for the lead removal from municipal tap water. Grafted and sol-gel immobilized tetra-aza-macrocyclic complexes are used as specific adsorbents for the purification and detection of gases, while related functionalized silica-gels have been implemented in the solid/liquid extraction processes of metals. (authors)

  1. New purification and upgrading technologies for biogas; Nya renings- och uppgraderingstekniker foer biogas

    Energy Technology Data Exchange (ETDEWEB)

    Johan Benjaminsson [Linkoeping Univ. (Sweden)


    Biogas is a renewable energy source that is produced by anaerobic digestion of organic material. In Sweden, biogas predominately comes from sewage water sludge and landfills or from organic waste of households and industries. Small scale digestion plants at farms are especially expected to contribute to increased biogas production in the future. Biogas can be obtained directly in its raw form and used as fuel in a combustion chamber. However, gas engines require biogas purification from hydrogen sulphide and drying from water to avoid corrosion. In order to increase the calorific value, carbon dioxide is separated and the Swedish Standard Type A requires the methane content to be 97 % for vehicle gas. In the gas treatment process from biogas to vehicle gas, the upgrading step when carbon dioxide is separated represents the highest cost since conventional upgrading techniques require high investments. This makes the upgrading costs for smaller biogas plants relatively high. In this master thesis, six upgrading methods have been evaluated and four of them are expected to be commercialized within two years. The following upgrading methods are of interest for Sweden: - In situ methane enrichment; air desorbs carbon dioxide from the sludge in a desorption column. The method is intended for digestion of sewage water sludge and the total upgrading cost is approximately 0,13 kr/kWh by a raw biogas flow 62,5 Nm{sup 3}/h. - Small scale water scrubber; carbon dioxide is absorbed in water under enhanced pressure. The upgrading process is very similar to the conventional water scrubbing technique and the total upgrading cost is approximately 0,42 kr/kWh by a raw biogas flow of 12 Nm{sup 3}/h. - Cryogenic upgrading; the biogas is chilled to under -85 deg C under a pressure of at least 5,2 barg and carbon dioxide can be separated in the liquid phase. The total upgrading cost is approximately 0,12 kr/kWh by a raw biogas flow of 150 Nm{sup 3}/h. The total upgrading cost can be

  2. Connectable solar air collectors

    Energy Technology Data Exchange (ETDEWEB)

    Oestergaard Jensen, S.; Bosanac, M.


    The project has proved that it is possible to manufacture solar air collector panels, which in an easy way can be connected into large collector arrays with integrated ducting without loss of efficiency. The developed connectable solar air collectors are based on the use of matrix absorbers in the form of perforated metal sheets. Three interconnected solar air collectors of the above type - each with an transparent area of approx. 3 m{sup 2} - was tested and compared with parallel tests on two single solar air collectors also with a transparent area of approx. 3 m{sup 2} One of the single solar air collectors has an identical absorber as the connectable solar air collectors while the absorber of the other single solar air collector was a fibre cloth. The efficiency of the three solar air collectors proved to be almost identical in the investigated range of mass flow rates and temperature differences. The solar air collectors further proved to be very efficient - as efficient as the second most efficient solar air collectors tested in the IEA task 19 project Solar Air Systems. Some problems remain although to be solved: the pressure drop across especially the connectable solar air collectors is too high - mainly across the inlets of the solar air collectors. It should, however, be possible to considerably reduce the pressure losses with a more aerodynamic design of the inlet and outlet of the solar air collectors; The connectable solar air collectors are easy connectable but the air tightness of the connections in the present form is not good enough. As leakage leads to lower efficiencies focus should be put on making the connections more air tight without loosing the easiness in connecting the solar air collectors. As a spin off of the project a simple and easy way to determine the efficiency of solar, air collectors for pre-heating of fresh air has been validated. The simple method of determining the efficiency has with success been compared with an advance method

  3. [Protoplasts isolation, purification and plant regeneration of Pinellia cordata]. (United States)

    Yang, Xian; Ma, Dan-Dan; Jiang, Fu-Sheng; Chen, Ni-Pi; Ding, Bin; Jin, Li-Xia; Qian, Chao-Dong; Ding, Zhi-Shan


    The main factors which affected the isolation, purification and cultivation of Pinellia cordata protoplasts from leaves were studied. The results indicated that the optimum enzyme solution for P. cordata leaves was 13% CPW + 1.0% Cellulose +0.1% Pectolase, at pH 6.0, temperature (25-28 degrees C ) for 4 h. The sucrose density gradient centrifugation was adopted to purificate the protoplasts collected, when 25% sucrose was used as mediator, centrifugating at 500 rpm for 10 min. When the protoplasts were shallow liquid and liquid-solid double layer cultured on the medium of MS + 0.5 mg x L(-1) 6-BA + 0.25 mg x L(-1) NAA + 13% mannitol at the density of 2.5 x 104 protoplasts/mL, or fed and nursed cultured at the density of 100-500 protoplasts/mL, cell division could be observed for 3 days; granular calli appeared for 30 days. Calli was proliferated on the medium of MS + 0.5 mg x L(-1) 6-BA + 0.25 mg x L(-1) NAA solidified by 0.55% agar, and differentiated and regenerated after 5-6 months. Plant generation of P. cordata is successfully established.


    Directory of Open Access Journals (Sweden)

    R. Satheeskumar


    Full Text Available Partial purification and characterization of alkalophilic protease production from Pseudomonas aeruginosa was isolated from the gut of marine and coastal waters shrimp Penaeus monodon. The protease production was assayed in submerged fermentation to produce maximum protease activity (423 ± 0.09 U/ml. The enzyme was precipitated with ammonium sulphate and partially purified by ion exchange chromatography through DEAE Sephadex A-50 column. In 10th fraction showed maximum protease activity (734 ± 0.18 U/ml with increase in purification fold. The molecular weight of protease from Pseudomonas aeruginosa was recorded as 60 kDa. The stability of protease was tested at various pH and temperature; it showed maximum protease activity at pH-9 and temperature 50ºC. Among the various surfactants tested for enzyme stability, maximum activity was retained in poly ethylene glycol. The compatibility of protease enzyme with various commercial detergents; the enzyme retained maximum protease activity in tide. The results are indicated that all these properties make the bacterial proteases are most suitable for wide industrial applications.

  5. Purification of metal electroplating waste waters using zeolites. (United States)

    Alvarez-Ayuso, E; García-Sánchez, A; Querol, X


    The sorption behaviour of natural (clinoptilolite) and synthetic (NaP1) zeolites has been studied with respect to Cr(III), Ni(II), Zn(II), Cu(II) and Cd(II) in order to consider its application to purify metal finishing waste waters. The batch method has been employed using metal concentrations in solution ranged from 10 to 200 mg/l and solid/liquid ratios ranged from 2.5 to 10 g/l. The Langmuir model was found to describe well all sorption processes, allowing to establish metal sorption sequences from which the main retention mechanism involved for each metal has been inferred. Synthetic zeolite exhibited about 10 times greater sorption capacities (b(Cr)=0.838 mmol/g, b(Ni)=0.342 mmol/g, b(Zn)=0.499 mmol/g, b(Cu)=0.795 mmol/g, b(Cd)=0.452 mmol/g) than natural zeolite (b(Cr)=0.079 mmol/g, b(Ni)=0.034 mmol/g, b(Zn)=0.053 mmol/g, b(Cu)=0.093 mmol/g, b(Cd)=0.041 mmol/g), appearing, therefore, as most suitable to perform metal waste water purification processes. This mineral showed the same high sorption capacity values when used in the purification of metal electroplating waste waters.

  6. Purification of total DNA extracted from activated sludge

    Institute of Scientific and Technical Information of China (English)


    Purification of the total DNA extracted from activated sludge samples was studied. The effects of extraction buffers and lysis treatments (lysozyme, sodium dodecyl sulfate (SDS), sonication, mechanical mill and thermal shock) on yield and purity of the total DNA extracted from activated sludge were investigated. It was found that SDS and mechanical mill were the most effective ways for cell lysis, and both gave the highest DNA yields, while by SDS and thermal shock, the purest DNA extract could be obtained. The combination of SDS with other lysis treatment, such as sonication and thermal shock, could apparently increase the DNA yields but also result in severe shearing. For the purification of the crude DNA extract, polyvinyl polypyrrolidone was used for the removal of humic contaminants. Cetyltrimethyl ammonium bromide, potassium acetate and phenol/chloroform were used to remove proteins and polysaccharides from crude DNA. Crude DNA was further purified by isopropanol precipitation. Thus, a suitable protocol was proposed for DNA extraction, yielding about 49.9 mg (DNA)/g volatile suspended solids, and the DNA extracts were successfully used in PCR amplifications for 16S rDNA and 16S rDNA V3 region. The PCR products of 16S rDNA V3 region allowed the DGGE analysis (denatured gradient gel electrophoresis) to be possible.

  7. Affinity purification of copper chelating peptides from chickpea protein hydrolysates. (United States)

    Megías, Cristina; Pedroche, Justo; Yust, Maria M; Girón-Calle, Julio; Alaiz, Manuel; Millan, Francisco; Vioque, Javier


    Chickpea protein hydrolysates obtained with alcalase and flavourzyme were used for purification of copper chelating peptides by affinity chromatography using copper immobilized on solid supports. The chelating activity of purified peptides was indirectly measured by the inhibition of beta-carotene oxidation in the presence of copper. Two protein hydrolysates, obtained after 10 and 100 min of hydrolysis, were the most inhibitory of beta-carotene oxidation. Purified copper chelating peptides from these protein hydrolysates contained 19.7 and 35.1% histidine, respectively, in comparison to 2.7 and 2.6% in the protein hydrolysates. Chelating peptides from hydrolysate obtained after 10 min of hydrolysis were the most antioxidative being 8.3 times more antioxidative than the hydrolysate, while chelating peptides purified from protein hydrolysate obtained after 100 min were 3.1 times more antioxidative than its hydrolysate. However, the histidine content was higher in peptides derived from the 100 min hydrolysate (19.7 against 35.1% in 10 min hydrolysate), indicating that this amino acid is not the only factor involved in the antioxidative activity, and other factors such as peptide size or amino acid sequence are also determinant. This manuscript shows that affinity chromatography is a useful procedure for purification of copper chelating peptides. This method can be extended to other metals of interest in nutrition, such as calcium, iron, or zinc. Purified chelating peptides, in addition to their antioxidative properties, may also be useful in food mineral fortification for increasing the bioavailability of these metals.

  8. Kilogram-scale purification of americium by ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Wheelwright, E. J.


    Sequential anion and cation exchange processes have been used for the final purification of /sup 241/Am recovered during the reprocessing of aged plutonium metallurgical scrap. Plutonium was removed by absorption of Dowex 1, X-3.5 (30 to 50 mesh) anion exchange resin from 6.5 to 7.5 M HNO/sub 3/ feed solution. Following a water dilution to 0.75 to 1.0 M HNO/sub 3/, americium was absorbed on Dowex 50W, X-8 (50 to 100 mesh) cation exchange resion. Final purification was accomplished by elution of the absorbed band down 3 to 4 successive beds of the same resin, preloaded with Zn/sup 2 +/, with an NH/sub 4/OH buffered chelating agent. The recovery of mixed /sup 241/Am-/sup 243/Am from power reactor reprocessing waste has been demonstrated. Solvent extraction was used to recover a HNO/sub 3/ solution of mixed lanthanides and actinides from waste generated by the reprocessng of 13.5 tons of Shippingport Power Reactor blanket fuel. Sequential cation exchange band-displacement processes were then used to separate americium and curium from the lanthanides and then to separate approx. 60 g of /sup 244/Cm from 1000 g of mixed /sup 241/Am-/sup 243/Am.

  9. Electrochemical alkaline Fe(VI) water purification and remediation. (United States)

    Licht, Stuart; Yu, Xingwen


    Fe(VI) is an unusual and strongly oxidizing form of iron, which provides a potentially less hazardous water-purifying agent than chlorine. A novel on-line electrochemical Fe(VI) water purification methodology is introduced. Fe(VI) addition had been a barrier to its effective use in water remediation, because solid Fe(VI) salts require complex (costly) syntheses steps and solutions of Fe(VI) decompose. Online electrochemical Fe(VI) water purification avoids these limitations, in which Fe(VI) is directly prepared in solution from an iron anode as the FeO42- ion, and is added to the contaminant stream. Added FeO42- decomposes, by oxidizing a wide range of water contaminants including sulfides (demonstrated in this study) and other sulfur-containing compounds, cyanides (demonstrated in this study), arsenic (demonstrated in this study), ammonia and other nitrogen-containing compounds (previously demonstrated), a wide range of organics (phenol demonstrated in this study), algae, and viruses (each previously demonstrated).

  10. A Simple Method for Synthesis, Purification and concentration Stabilized Goldnanoparticles

    Directory of Open Access Journals (Sweden)

    Dr. Fatin F.M. AL-Kazazz


    Full Text Available The greatest barriers to biological nanoparticles in use are issues of particle stability in shape and size control. Simple process is desirable for several reasons likewide range of sample volumes, gentle conditions and inexpensive equipment. Gold nanoparticles(GNPs which are produced by reducing gold chloride with TSC have very limited time storage. In order to get highly stable nanoparticles, purification has been performed for industrial applications. Removal of the side product of the reaction between HAuCl4 with Tri-Sodium Citrate (TSCis considered to make GNPs more stable. The result demonstrates that GNPs are more stable after the purification process. Low degree of polydispersity can be achieved during gold nanoparticles synthesis, however, the particles need to be purified post-synthesis. The present research relates to single process for the removal of small-molecule impurities and the isolation of small nanoparticles from larger nanostructures through dialysis and microfiltration then concentration these small nanoparticles through polymer adsorbent materials by a factor of 100 or more to storage in the room temperature prolongs the stability of the purified gold nanoparticles suspension up to one year.The size and shape of the GNps is measured by atomic force microscopy (AFM, and the optical properties by UV-Vis spectrometer.

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

    Energy Technology Data Exchange (ETDEWEB)

    Alekseev, I.; Arkhipov, Ev.; Bondarenko, S.; Fedorchenko, O.; Ganzha, V.; Ivshin, K.; Kravtsov, P., E-mail:; Trofimov, V.; Vasilyev, A.; Vasyanina, T.; Vorobyov, A.; Vznuzdaev, M. [National Research Center “Kurchatov Institute” Petersburg Nuclear Physics Institute (NRC “Kurchatov Institute” PNPI), 188300 Gatchina (Russian Federation); Kammel, P. [Department of Physics, University of Washington, Seattle, Washington 98195 (United States); Petitjean, C. [Paul Scherrer Institut (PSI), CH-5232 Villigen (Switzerland)


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

  12. Protein purification by aminosquarylium cyanine dye-affinity chromatography. (United States)

    Silva, M S; Graça, V C; Reis, L V; Santos, P F; Almeida, P; Queiroz, J A; Sousa, F


    The most selective purification method for proteins and other biomolecules is affinity chromatography. This method is based on the unique biological-based specificity of the biomolecule-ligand interaction and commonly uses biological ligands. However, these ligands may present some drawbacks, mainly because of their cost and lability. Dye-affinity chromatography overcomes the limitations of biological ligands and is widely used owing to the low cost of synthetic dyes and to their resistance to biological and chemical degradation. In this work, immobilized aminosquarylium cyanine dyes are used in order to exploit affinity interactions with standard proteins such as lysozyme, α-chymotrypsin and trypsin. These studies evaluate the affinity interactions occurring between the immobilized ligand and the different proteins, as a reflection of the sum of several molecular interactions, namely ionic, hydrophobic and van der Waals, spread throughout the structure, in a defined spatial manner. The results show the possibility of using an aminosquarylium cyanine dye bearing a N-hexyl pendant chain, with a ligand density of 1.8 × 10(-2) mmol of dye/g of chromatographic support, to isolate lysozyme, α-chymotrypsin and trypsin from a mixture. The application of a decreasing ammonium sulfate gradient resulted in the recovery of lysozyme in the flowthrough. On the other hand, α-chymotrypsin and trypsin were retained, involving different interactions with the ligand. In conclusion, this study demonstrates the potential applicability of ligands such as aminosquarylium cyanine dyes for the separation and purification of proteins by affinity chromatography.

  13. Research on purification and modification of I/S bentonite

    Institute of Scientific and Technical Information of China (English)

    Deli YU; Shufeng LIU; Liyu TIAN; Peiping ZHANG


    Analyzing raw material's structure and performance of bentonite from Panzhihua in Sichuan, the authors think that it is adequate for agglomerant of iron smelting. According to its composition and property we have researched the purification and modification of I/S bentonite under conditions of different dispersants and sodium agent. XRD test result reveals that the essential minerals of Panzhihua bentonite are I/S mixed-layer ones, and FTIR analysis shows that when adding 1 5% sodium pyrophosphate to the bentonite slurry during purification, the composition of quartz in bentonite decreases to less than 4% and I/S is more than 90%. The optimized modification technic conditions are Na2CO3 (4%) and CMC-Na (3%) as modified agents, the clay and water are 10 vs. 1, and the temperature is 75℃. It is 40 min for stirring time and reacting time is 4 h. Under the conditions we can get the modified I/S bentonite with colloid index more than 500 ml/15 g.

  14. Expression and affinity purification of recombinant proteins from plants (United States)

    Desai, Urvee A.; Sur, Gargi; Daunert, Sylvia; Babbitt, Ruth; Li, Qingshun


    With recent advances in plant biotechnology, transgenic plants have been targeted as an inexpensive means for the mass production of proteins for biopharmaceutical and industrial uses. However, the current plant purification techniques lack a generally applicable, economic, large-scale strategy. In this study, we demonstrate the purification of a model protein, beta-glucuronidase (GUS), by employing the protein calmodulin (CaM) as an affinity tag. In the proposed system, CaM is fused to GUS. In the presence of calcium, the calmodulin fusion protein binds specifically to a phenothiazine-modified surface of an affinity column. When calcium is removed with a complexing agent, e.g., EDTA, calmodulin undergoes a conformational change allowing the dissociation of the calmodulin-phenothiazine complex and, therefore, permitting the elution of the GUS-CaM fusion protein. The advantages of this approach are the fast, efficient, and economical isolation of the target protein under mild elution conditions, thus preserving the activity of the target protein. Two types of transformation methods were used in this study, namely, the Agrobacterium-mediated system and the viral-vector-mediated transformation system. Copyright 2002 Elsevier Science (USA).

  15. The purification mechanism of wastewater by underwater discharge (United States)

    Kim, Kangil; Ma, Suk Hwal; Huh, Jin Young; Hong, Yong Cheol; National Fusion Research Institute Team; Chonbuk National University Team; Kwangwoon University Team; NPAC Team


    There is a continuing need for development of effective, cheap and environmentally friendly processes for purification of wastewater. In this regard, the plasmas can be a promising candidate for next-generation method to purify the wastewater. It is well known that the plasmas generate many reactive species and thus they are predominant for degradation of organic pollutants from water. In order to generate plasma in wastewater, the capillary electrodes are used with ac power supply. After plasma treatment, the coagulants are added to purify the wastewater. The efficiency of coagulation is significantly improved by plasma treatment of wastewater. These results may come from the reactions among radicals of plasma-treated water, electron reduction and oxidation of ions in waste water, and coagulant. In order to verify the hypothesis, we measured characteristics changes of water by underwater discharge. In this study, we propose the purification mechanism of wastewater by underwater discharge. We expect that the underwater discharge can be applied to purify wastewater in near future.

  16. Simple optimization method for partitioning purification of hydrogen networks

    Directory of Open Access Journals (Sweden)

    W.M. Shehata


    Full Text Available The Egyptian petroleum fuel market is increasing rapidly nowadays. These fuels must be in the standard specifications of the Egyptian General Petroleum Corporation (EGPC, which required lower sulfur gasoline and diesel fuels. So the fuels must be deep hydrotreated which resulted in increasing hydrogen (H2 consumption for deeper hydrotreating. Along with increased H2 consumption for deeper hydrotreating, additional H2 is needed for processing heavier and higher sulfur crude slates especially in hydrocracking process, in addition to hydrotreating unit, isomerization units and lubricant plants. Purification technology is used to increase the amount of recycled hydrogen. If the amount of recycled hydrogen is increased, the amount of hydrogen that is sent to the furnaces with the off gas will decrease. In this work, El Halwagi et al. (2003 and El Halwagi (2012 optimization methods which are used for recycle/reuse integration systems have been extended to be used in the partitioning purification of hydrogen networks to minimize the hydrogen consumption and the hydrogen discharge. An actual case study and two case studies from the literature are solved to illustrate the proposed method.

  17. Purification of human monoclonal antibodies and their fragments. (United States)

    Müller-Späth, Thomas; Morbidelli, Massimo


    This chapter summarizes the most common chromatographic mAb and mAb fragment purification methods, starting by elucidating the relevant properties of the compounds and introducing the various chromatography modes that are available and useful for this application. A focus is put on the capture step affinity and ion exchange chromatography. Aspects of scalability play an important role in judging the suitability of the methods. The chapter introduces also analytical chromatographic methods that can be utilized for quantification and purity control of the product. In the case of mAbs, for most purposes the purity obtained using an affinity capture step is sufficient. Polishing steps are required if material of particularly high purity needs to be generated. For mAb fragments, affinity chromatography is not yet fully established, and the capture step potentially may not provide material of high purity. Therefore, the available polishing techniques are touched upon briefly. In the case of mAb isoform and bispecific antibody purification, countercurrent chromatography techniques have been proven to be very useful and a part of this chapter has been dedicated to them, paying tribute to the rising interest in these antibody formats in research and industry.

  18. Isolation and Purification of Jacalin from Artocarpus Heterophyllus Lam

    Directory of Open Access Journals (Sweden)

    M.R. Othman


    Full Text Available This paper presents investigation results of saturation conditions needed for purification of jacalin lectin from the extract seeds of Artocarpus heterophyllus by ammonium precipitation and affinity chromatography on Galactose-Affi gel Hz. Three different aspects of parameters encompassing the percentage of saturation of ammonium sulfate precipitation, the presence of ammonium sulfate on Lowry method and the suitable galactose concentration for optimum elution of the protein from Galactose-Affi gel Hz were investigated. With three different sets of fractional saturation of jacalin purification using ammonium sulfate precipitation, the maximum yield of 0.463 g/g was achieved at 0-90% saturation range in the absence of dialysis. Maximum yield of 0.425 g/g was obtained at 30-60% and 0-90% saturation range in the presence of dialysis. The result from this work also indicates that excessive quantity of NH4SO4 interferes with Lowry method for protein determination substantially. The 0-90% saturation range was found to be more potentially appropriate for large scale application than 30-60% saturation, since the former involves only 1 step NH4SO4 addition. From the affinity chromatography, elution of 0.2 M galactose (in 0.15 M NaCl from Galactose-Affi gel Hz produced the maximum peak profile and jacalin concentration. A reduction or increase in galactose concentration of more than 0.2 M did not increase concentration of purified jacalin purified using this method.

  19. Purification of mammalian DNA repair protein XRCC1

    Energy Technology Data Exchange (ETDEWEB)

    Chen, I. [Univ. of California, Berkeley, CA (United States)


    Malfunctioning DNA repair systems lead to cancer mutations, and cell death. XRCC1 (X-ray Repair Cross Complementing) is a human DNA repair gene that has been found to fully correct the x-ray repair defect in Chinese hamster ovary (CHO) cell mutant EM9. The corresponding protein (XRCC1) encoded by this gene has been linked to a DNA repair pathway known as base excision repair, and affects the activity of DNA ligase III. Previously, an XRCC1 cDNA minigene (consisting of the uninterrupted coding sequence for XRCC1 protein followed by a decahistidine tag) was constructed and cloned into vector pET-16b for the purpose of: (1) overproduction of XRCC1 in both prokaryotic and eukaryotic cells; and (2) to facilitate rapid purification of XRCC1 from these systems. A vector is basically a DNA carrier that allows recombinant protein to be cloned and overexpressed in host cells. In this study, XRCC1 protein was overexpressed in E. coli and purified by immobilized metal affinity chromatography. Currently, the XRCC1 minigene is being inserted into a new vector [pET-26b(+)] in hopes to increase overexpression and improve purification. Once purified XRCC1 can be crystallized for structural studies, or studied in vitro for its biological function.

  20. Process development and optimisation of lactic acid purification using electrodialysis. (United States)

    Madzingaidzo, L; Danner, H; Braun, R


    Cell free sodium lactate solutions were subjected to purification based on mono- and bi-polar electrodialysis. Lactate concentration in the product stream increased to a maximum of 15% during mono-polar electrodialysis. Stack energy consumption averaged 0.6 kW h kg(-1) lactate transported at current efficiencies in the 90% range. Under optimum feed concentration (125 g l(-1)) and process conditions (auto-current mode with conductivity setpoints of minimum 5 and maximum 40 mS cm(-1)), lactate flux reached 300 g m(-2) h(-1) and water flux were low for mono-polar electrodialysis averaging 0.3 kg H(2)O per M lactate transported. Glucose in the concentrate stream solutions was reduced to concentrate stream solutions. After mono-polar electrodialysis, the concentrated sodium lactate solutions were further purified using bi-polar electrodialysis. Water transport during bi-polar electrodialysis reached figures of 0.070 - 0.222 kg H(2)O per M lactate. Free lactic acid concentration reached 16% with lactate flux of up to 300 g m(-2) h(-1). Stack energy consumption ranged from 0.6 to 1 kW h per kg lactate. Under optimised process conditions current efficiency during bi-polar electrodialysis was consistently around 90%. Glucose was further reduced from 2 to solution. Acetic acid impurity remained at around 1 g l(-1). Significant reduction in colour and minerals in the product streams was observed during electrodialysis purification.

  1. Purification of fructooligosaccharides in an activated charcoal fixed bed column. (United States)

    Kuhn, Raquel Cristine; Filho, Francisco Maugeri


    Fructooligosaccharides (FOS) are mixtures of oligosaccharides containing mono and disaccharides, therefore, the separation of these sugars results in purer products for human consumption and can be added to various food products (drinks, cookies and yogurt). The aim of this work was the purification of fructooligosaccharides from a mixture of sugars, obtained by enzymatic synthesis, containing fructooligosaccharides, glucose, fructose and sucrose using activated charcoal fixed bed column. Temperature and ethanol concentration effects were analyzed using a 2² central composite design. Good separation conditions were obtained through central composite design. The best separation coefficient between fructooligosaccharides and glucose (ES(fructoolig/gluc)) was 3.99 ± 0.07 and between fructose and fructooligosaccharides (ES(fructoolig/fruct)) was 2.89 ± 0.36 using ethanol 15% (v/v) as eluent, at 50°C. The final FOS purification degree and recovery were about 80% and 97.8%, respectively. The activated charcoal fixed bed columns were shown to be a good alternative for sugar separation, especially for rich mixtures of fructooligosaccharides.

  2. Production and purification of polyclonal antibody against melatonin hormone

    Directory of Open Access Journals (Sweden)

    Fooladsaz K


    Full Text Available Nowadays immunochemical techniques have played a very important and valuable role in quantitative and qualitative assays of liquid compounds of the body. Producing antibody against immunogenes is the first step to make immunochemical kits. In this study production and purification of polyclonal antibody against melatonin has been considered. This hormone which has several important functions in physiological conditions such as migraine, cirrhosis, mammary gland cancer and other diseases, is the most important pineal gland secretion. This gland is a circumventricular organ of brain and according to histological and anatomical studies, it is a high secretory organ, that secretes active biological substances like melatonin, oxytocin, serotonin and ect. In this study, melatonin has been considered as hapten and has become an immunogen by being linked to the bovine serum Albumin. Then, by the immunization of three white New Zeland rabbits that had the booster injections in regular intervals, the antibody titer was detected to be 1/2000, by using checkboard curves, and with the use of melatonin linked to penicillinase as a labeled antigen, the titer was detected 1/200. Finally an antibody with high purification rate has been obtained, which can be used in immunochemical assays like RIA, ELISA, and EIA.

  3. Caract\\'erisation de r\\'eacteurs photocatalytiques utilis\\'es pour le traitement de l'air

    CERN Document Server

    Faure, Marie; Corbel, Serge; Carré, Marie-Christiane; Gérardin, Fabien; Zahraa, Orfan


    Photocatalysis is often used in air purification. Photocatalytic degradation od VOC's has been investigated in a number of devices. An optimisation of this process requires a chracterisation of the reactor : in a first step the gas flow behaviour has to be studied (plug flow, CSTR,...) by RTD analysis; then, chemical kinetics have to be determined as a function ot the relevant parameters (space time, relative humidity, concentrations, etc). All the data collected lead to a reliable design of the equipment.

  4. Tetanus toxoid purification: chromatographic procedures as an alternative to ammonium-sulphate precipitation. (United States)

    Stojićević, Ivana; Dimitrijević, Ljiljana; Dovezenski, Nebojša; Živković, Irena; Petrušić, Vladimir; Marinković, Emilija; Inić-Kanada, Aleksandra; Stojanović, Marijana


    Given an existing demand to establish a process of tetanus vaccine production in a way that allows its complete validation and standardization, this paper focuses on tetanus toxoid purification step. More precisely, we were looking at a possibility to replace the widely used ammonium-sulphate precipitation by a chromatographic method. Based on the tetanus toxin's biochemical characteristics, we have decided to examine the possibility of tetanus toxoid purification by hydrophobic chromatography, and by chromatographic techniques based on interaction with immobilized metal ions, i.e. chelating chromatography and immobilized metal affinity chromatography. We used samples obtained from differently fragmented crude tetanus toxins by formaldehyde treatment (assigned as TTd-A and TTd-B) as starting material for tetanus toxoid purification. Obtained results imply that purification of tetanus toxoid by hydrophobic chromatography represents a good alternative to ammonium-sulphate precipitation. Tetanus toxoid preparations obtained by hydrophobic chromatography were similar to those obtained by ammonium-sulphate precipitation in respect to yield, purity and immunogenicity. In addition, their immunogenicity was similar to standard tetanus toxoid preparation (NIBSC, Potters Bar, UK). Furthermore, the characteristics of crude tetanus toxin preparations had the lowest impact on the final purification product when hydrophobic chromatography was the applied method of tetanus toxoid purification. On the other hand, purifications of tetanus toxoid by chelating chromatography or immobilized metal affinity chromatography generally resulted in a very low yield due to not satisfactory tetanus toxoid binding to the column, and immunogenicity of the obtained tetanus toxoid-containing preparations was poor.

  5. AirCompare (United States)

    U.S. Environmental Protection Agency — AirCompare contains air quality information that allows a user to compare conditions in different localities over time and compare conditions in the same location...

  6. Allegheny County Air Quality (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Air quality data from Allegheny County Health Department monitors throughout the county. Air quality monitored data must be verified by qualified individuals before...

  7. Air Quality Facilities (United States)

    Iowa State University GIS Support and Research Facility — Facilities with operating permits for Title V of the Federal Clean Air Act, as well as facilities required to submit an air emissions inventory, and other facilities...

  8. Indoor Air Pollution (United States)

    We usually think of air pollution as being outdoors, but the air in your house or office could also be polluted. Sources of indoor pollution include Mold and pollen Tobacco smoke Household products ...

  9. Air Quality System (AQS) (United States)

    U.S. Environmental Protection Agency — The Air Quality System (AQS) database contains measurements of air pollutant concentrations from throughout the United States and its territories. The measurements...

  10. Preparation of DNA-adsorbed TiO2 particles with high performance for purification of chemical pollutants. (United States)

    Suzuki, Hiroshi; Amano, Takeharu; Toyooka, Tatsushi; Ibuki, Yuko


    Photocatalysis using semiconductors such as titanium dioxide (TiO2) has been studied and applied to the treatment of wastewater and purification of air, because of its ability to decompose organic contaminants. However, there are still problems associated with the practical application of photocatalytic reactions, one of which is that contact between the reactants and catalysts is absolutely required, because the reaction occurs atthe surface of the catalysts. This restrictsthe purification of pollutants on a large scale. In this study, we developed novel DNA-adsorbed TiO2 particles (DNA-TiO2) to solve the problem. Because DNA has an unique double-stranded structure and interacts with several chemicals, DNA-TiO2 can accumulate chemicals on the surface of TiO2. DNA intercalators (Methylene Blue and ethidium bromide), small amounts of which exist in large-volume solutions, were instantaneously trapped in DNA-TiO2 and degraded under ultraviolet (UV) light rapidly, compared to nonadsorbed TiO2. The efficiency of removal and photocatalytic degradation was dependent on the amount of DNA adsorbed on the surface of TiO2 and was independent of the size of DNA. Even if the pH (2-10) and temperature (approximately 56 degrees C) of the solution were changed, DNA remained stable on TiO2, and the ability to remove intercalators was also maintained. DNA-TiO2 could accumulate other pigments such as Acridine Orange, Orange II, Neutral Red, Brilliant Green, and Crystal Violet. These results suggested that DNA-TiO2 is beneficial for the removal and degradation of chemicals having affinity for DNA and dispersing in a large field.

  11. Air Power and Warfare (United States)


    Memorial, 1963. (T) 767.8 A3 ser .3, V.4) Air war against Germany and Italy, 1939-1943. Canberra: Australian War Memorial, 1954. (D 767.8 A3 Ser .3, al. Air poder indivisible Air University Ouarterly Review 2:5-18, Fall 1950. Spaatz, Crrl. Air-power odds against us. Readers Digest 58:11-14, June

  12. Indoor air quality

    DEFF Research Database (Denmark)

    Jensen, Trine Susanne; Recevska, Ieva

     The objective of the 35th specific agreement is to provide support to the EEA activities in Environment and Health (E&H) on the topic of indoor air quality. The specific objectives have been to provide an overview of indoor air related projects in EU and indoor air related policies as well...... as idenfiying "good practices" to reduce health impact of indoor air exposure and suggest areas for future improvements....

  13. The development trend of indoor air purifier%室内空气净化器的发展趋势

    Institute of Scientific and Technical Information of China (English)

    乔鑫; 罗卫东; 刘晶茹; 杨晓涵; 黄嘉诚


    In view of current indoor air pollution problems,this paper elaborated the development process of indoor air purifier,introduced its production and sales situation,summed up the characteristics of several common indoor air purifier technology,in order to improve the air purifi-cation technology level,to improve indoor air quality.%针对现今室内空气污染的问题,阐述了室内空气净化器的发展历史,并对其产销量现状进行了介绍,归纳总结了几种常见的室内净化器技术的特点,以提高空气净化技术水平,从而改善室内空气质量。

  14. Modelling of the filter-adsorber type air cleaner by using neural network

    Directory of Open Access Journals (Sweden)

    Raos Miomir


    Full Text Available It is well known that most air purifying methods imply the passing of air flow, as a pollutant carrier, through a control unit which retains impurities. Properties of the air control unit and the purifying process itself therefore differ depending on the nature of present impurities, as well as on flow-thermal properties of air as the carrier of those impurities. For the assumed conditions, in terms of production of a pollution source and presence of different polluting substances in the form of dust, aerosols, gas, vapor in the exhaust gas, etc., an integrated gas purifier has been designed and tested, comprising a module for purification of mechanical impurities and a module for purification of gaseous impurities. The purifier is compact and has a universal application while simultaneously retaining several different pollutants. These requirements were met through application of the filtration and adsorption methods. On the formed experimental line with an adequate system of acquisition, filter-adsorber type gas cleaners in the function of flow-thermal parameters of gas mixture were tested simultaneously. Experimental data were used for training the radial basis function neural network, which was then used to model properties of the process and gas cleaner.

  15. We Pollute the Air

    Institute of Scientific and Technical Information of China (English)


    1.Clean air is important to good health.If the aircontains impurities,they may be absorbed by ourbodies and make us ill.We need clean air,butunfortunately,air pollution is generally present,especially in cities. 2.Our cities have many factories,which we need tomake food products,clothing and many other things.

  16. Air Pollution Training Programs. (United States)

    Public Health Service (DHEW), Rockville, MD.

    This catalog lists the universities, both supported and not supported by the Division of Air Pollution, which offer graduate programs in the field of air pollution. The catalog briefly describes the programs and their entrance requirements, the requirements, qualifications and terms of special fellowships offered by the Division of Air Pollution.…

  17. High-speed countercurrent chromatography for purification of single-walled carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    Ying Cai; Zhi Hong Yan; Ying Chun Lv; Min Zi; Li Ming Yuan


    A new chromatographic purification of single-walled carbon nanotubes using high-speed countercurrent chromatography is reported.The purification was accomplished on the basis of experiment that dispersed the single-walled carbon nanotubes with sodium dodecyl sulfate,and the result mixture was separated using the two phase system composed of n-butanol/water=1/1 (v/v).The sizes of SWNTs separated were observed by scanning electron microscopy.The results demonstrated that the high-speed countercurrent chromatography possessed a good efficency for purification of single-walled carbon nanotubes.

  18. Practice and design of the self-purification system for heavy metals-bearing contaminants

    Institute of Scientific and Technical Information of China (English)

    Qian Guangren


    Many minerals in nature have self-purification capacity to hold and stabilize deleterious contaminants into their lattice structures,which can be used for treatment of heavy metals-bearing contaminants.Hydrotalcite Layer Double Hy-droxide(LDH),tobermorite Calcium Silicate Hydrate(CSH)and apatite are ubiquitous minerals in nature,having higher geochemical stability and potential for binding and stabilizing heavy metals.Based on the elucidation of crystal structure property and self-purification principles of the three minerals above,this article discussed how to design the self-purification system of heavy metal-bearing contaminants.

  19. Microscale purification of proteins by line immunoelectrophoresis: application of the technique in protein biogenesis studies

    DEFF Research Database (Denmark)

    Danielsen, E M; Cowell, G M


    A small-scale version of line immunoelectrophoresis in combination with immunoprecipitate excision is described as a rapid and convenient technique to purify proteins on a micro scale in biogenesis studies. In the purification and to result in a higher state of purity than an isolation procedure...... using protein A-Sepharose. Since the method furthermore allows a simultaneous purification of several different protein antigens from the same sample, it may be of interest as an alternative method to other procedures in the purification of proteins on a micro scale....

  20. Use of Escherichia coli for the production and purification of membrane proteins. (United States)

    Postis, Vincent G L; Rawlings, Andrea E; Lesiuk, Amelia; Baldwin, Stephen A


    Individual types of ion channels and other membrane proteins are typically expressed only at low levels in their native membranes, rendering their isolation by conventional purification techniques difficult. The heterologous over-expression of such proteins is therefore usually a prerequisite for their purification in amounts suitable for structural and for many functional investigations. The most straightforward expression host, suitable for prokaryote membrane proteins and some proteins from eukaryotes, is the bacterium Escherichia coli. Here we describe the use of this expression system for production of functionally active polytopic membrane proteins and methods for their purification by affinity chromatography in amounts up to tens of milligrams.

  1. Purification of prostatic acid phosphatase (PAP) for structural and functional studies. (United States)

    Herrala, Annakaisa M; Quintero, Ileana B; Vihko, Pirkko T


    High-scale purification methods are required for several protein studies such as crystallography, mass spectrometry, circular dichroism, and function. Here we describe a purification method for PAP based on anion exchange, L-(+)-tartrate affinity, and gel filtration chromatographies. Acid phosphatase activity and protein concentration were measured for each purification step, and to collect the fractions with the highest acid phosphatase activity the p-nitrophenyl phosphate method was used. The purified protein obtained by the procedure described here was used for the determination of the first reported three-dimensional structure of prostatic acid phosphatase.

  2. The controllability analysis of the purification system for heavy water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K. D.; Cho, B. H.; Shin, C. H.; Kim, S. H. [KEPRI, Taejon (Korea, Republic of); Lee, Y. K.; Kim, K. U. [KHNP, Kyungju (Korea, Republic of)


    The heavy water reactor such as Wolsung No.1 and No.2 has a purification system to purify the reactor coolant. The control system regulates the coolant temperature to protect the ion exchanger. After the fuel exchanges of operating plant, the increase of the coolant pressure makes the purification temperature control difficult. In this paper, the controllability of the control dynamics of the purification system was analysed and the optimal parameters were proposed. To reduce the effects of the flow disturbance, the feedforward control structure was proposed and analysed.

  3. Inteins and affinity resin substitutes for protein purification and scale up

    Directory of Open Access Journals (Sweden)

    Wood David W


    Full Text Available Abstract The development of self-cleaving fusion-tag technology has greatly simplified the purification of recombinant proteins at laboratory scale. The self-cleaving capability of these tags has recently been combined with additional purification tags to generate novel and convenient protein purification methods at a variety of scales. In this review, we describe some of these methods, and provide a rudimentary economic analysis of hypothetical large-scale applications. This work is expected to provide a rough outline for the evaluation of these methods for large-scale bioprocessing of a variety of products.

  4. Manual for THOR-AirPAS - air pollution assessment system

    DEFF Research Database (Denmark)

    Jensen, Steen Solvang; Ketzel, Matthias; Brandt, Jørgen

    The report provides an outline of the THOR-AirPAS - air pollution assessment system and a brief manual for getting started with the air quality models and input data included in THOR-AirPAS.......The report provides an outline of the THOR-AirPAS - air pollution assessment system and a brief manual for getting started with the air quality models and input data included in THOR-AirPAS....

  5. Air Conditioning Does Reduce Air Pollution Indoors (United States)

    Healy, Bud


    Report of the winter meeting of the American Society of Heating, Refrigerating and Air-Conditioning Engineers. Subjects covered are--(1) title subject, (2) predictions for the human habitat in 1994, (3) fans, and (4) fire safety in buildings. (JW)

  6. Purification and Characterization of Streptomyces sp. IK Chitinase

    Directory of Open Access Journals (Sweden)

    Sebastian Margino


    Full Text Available Streptomyces sp. IK isolated from compost inoculants, could produce extra cellular chitinase in a medium containing 0.2% (w/v colloidal chitin, fermented for 96 hours at 30oC. The enzyme was purified by a combination of ammonium sulphate precipitation and DEAE-Cellulose anion-exchange chromatography. On SDS-polyacrylamide gel electrophoresis analysis, the purified enzyme showed a mass of 71 kDa. Chitinase was optimally active at pH of 6.7 and at 37oC. Km value and Vmax of the protein for colloidal chitin were 2.92 mg/ml and 4.26 ìg/h, respectively.Key words : chitinase, Streptomyces, purification, characterization

  7. Production and partial purification of streptokinase from Streptococcus pyogenes

    Directory of Open Access Journals (Sweden)

    Freeda Felsia X


    Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 Streptokinase is as effective as recombinant tissue plasminogen activator (tPA in treating acute myocardial infarction and it is certainly more cost-effective. In view of the relatively recent availability of the competing recombinant tPA, skepticism is being expressed about the continued viability of streptokinase therapy. Despite this research on streptokinase continues, and it remains a vital affordable therapy especially in the world’s poorer healthcare systems. Our present study focused on production of streptokinase from Streptococcus pyogenes species and partial purification of streptokinase by ammonium sulfate precipitation, dialysis and column chromatography. The enzyme was quantified by Lowry’s method and its electrophoretic mobility and molecular weight were determined by SDS-PAGE.

  8. Gelatin blends with alginate: gels for lipase immobilization and purification. (United States)

    Fadnavis, Nitin W; Sheelu, Gurrala; Kumar, Bezavada Mani; Bhalerao, Mahendra U; Deshpande, Ashlesha A


    Blends of natural polysaccharide sodium alginate (5%) with gelatin (3%) cross-linked with glutaraldehyde provide beads with excellent compressive strength (8 x 10(4) Pa) and regular structure on treatment with calcium chloride. Lipases from porcine pancreas, Pseudomonas cepacia, and Candida rugosa were immobilized in such a blend with excellent efficiency. The immobilized enzymes were stable and were reused several times without significant loss of enzyme activity both in aqueous and reverse micellar media. The beads were functionalized with succinic anhydride to obtain beads with extra carboxylic acid groups. These functionalized beads were then successfully used for 7.4-fold purification of crude porcine pancreatic lipase in a simple operation of protein binding at pH 5 and release at pH 8.5.

  9. Affinity Monolith-Integrated Microchips for Protein Purification and Concentration. (United States)

    Gao, Changlu; Sun, Xiuhua; Wang, Huaixin; Qiao, Wei; Hu, Bo


    Affinity chromatography is a valuable method to purify and concentrate minute amount of proteins. Monoliths with epoxy groups for affinity immobilization were prepared by direct in-situ photopolymerization of glycidyl methacrylate and ethylene glycol dimethacrylate in porogenic solvents consisting of 1-dodecanol and cyclohexanol. By integrating affinity monoliths onto a microfluidic system, targeted biomolecules can be captured and retained on affinity column, while other biomolecules having no specific interactions toward the immobilized ligands flow through the microchannel. Therefore, proteins which remain on the affinity column are purified and concentrated, and then eluted by appropriate solutions and finally, separated by microchip capillary electrophoresis. This integrated microfluidic device has been applied to the purification and separation of specific proteins (FITC-labeled human serum albumin and IgG) in a mixture.

  10. Purification of cadmium up to 5N+ by vacuum distillation

    Indian Academy of Sciences (India)

    S T Ali; J V Rao; K S Varma; T L Prakash


    Cadmium was refined by vacuum distillation, a technique suitable for low boiling and melting point materials, to remove the heavy and low vapour pressure impurities at ppm level. The detailed analysis of the purified Cd as well as raw Cd was done by ICP–OES techniques for 27 impurity elements. Purification was carried out in an efficient high-yield vacuum distillation system designed and fabricated for purifying 3N+ purity indigenous cadmium to 5N+ (99.999%). Analysis confirmed the reduction of total impurity content from 134 ppm (3N7) for raw Cd to 3 ppm (5N7) upon vacuum distilled Cd. The present study shows that the analysis of impurities such as Fe, Mg and Ca are contributed from environmental effect, whereas impurities such as Pb, Bi, Ag, Ni, Cu, Zn and Tl require adaptation of elemental analysing technique to counter dilution effect. The Hg trace analysis can however be carried out by hydride generation techniques.

  11. A novel purification process for dodecanedioic acid by molecular distillation

    Institute of Scientific and Technical Information of China (English)

    Jiang Yu; Xigang Yuan; Aiwu Zeng


    A novel purification process is involved to obtain the high purity [N 99%(by mass)] dodecanedioic acid (DC12). It involves a re-crystal ization followed by molecular distil ation from the crude product. The objective of this study is to investigate general conditions, feed rate, distil ing temperature and vacuum, necessary for centrifugal distil-lation of DC12. Under the optimum conditions, distilling temperature 180 °C, pressure 30 Pa and feed flow rate 700 ml·h−1, the purity of DC12 in the residence reached 97.55%with a yield of 53.18%by the analysis of gas chromatography. Multiple-pass distillation made a considerable contribution by improving the purity to 99.22%. Additionally, the effect of pretreatment (re-crystallization) on distillation process was revealed through a series of comparative experiments.

  12. Efficient expression and purification of biologically active human cystatin proteins. (United States)

    Chauhan, Sakshi; Tomar, Raghuvir S


    Cystatins are reversible cysteine protease inhibitor proteins. They are known to play important roles in controlling cathepsins, neurodegenerative disease, and in immune system regulation. Production of recombinant cystatin proteins is important for biochemical and function characterization. In this study, we cloned and expressed human stefin A, stefin B and cystatin C in Escherichia coli. Human stefin A, stefin B and cystatin C were purified from soluble fraction. For cystatin C, we used various chaperone plasmids to make cystatin C soluble, as it is reported to localize in inclusion bodies. Trigger factor, GroES-GroEL, DnaK-DnaJ-GrpE chaperones lead to the presence of cystatin C in the soluble fraction. Immobilized metal affinity chromatography, glutathione sepharose and anion exchange chromatography techniques were employed for efficient purification of these proteins. Their biological activities were tested by inhibition assays against cathepsin L and H3 protease.

  13. Identification of protein interacting partners using tandem affinity purification. (United States)

    Bailey, Dalan; Urena, Luis; Thorne, Lucy; Goodfellow, Ian


    A critical and often limiting step in understanding the function of host and viral proteins is the identification of interacting cellular or viral protein partners. There are many approaches that allow the identification of interacting partners, including the yeast two hybrid system, as well as pull down assays using recombinant proteins and immunoprecipitation of endogenous proteins followed by mass spectrometry identification(1). Recent studies have highlighted the utility of double-affinity tag mediated purification, coupled with two specific elution steps in the identification of interacting proteins. This approach, termed Tandem Affinity Purification (TAP), was initially used in yeast(2,3) but more recently has been adapted to use in mammalian cells(4-8). As proof-of-concept we have established a tandem affinity purification (TAP) method using the well-characterized eukaryotic translation initiation factor eIF4E(9,10).The cellular translation factor eIF4E is a critical component of the cellular eIF4F complex involved in cap-dependent translation initiation(10). The TAP tag used in the current study is composed of two Protein G units and a streptavidin binding peptide separated by a Tobacco Etch Virus (TEV) protease cleavage sequence. The TAP tag used in the current study is composed of two Protein G units and a streptavidin binding peptide separated by a Tobacco Etch Virus (TEV) protease cleavage sequence(8). To forgo the need for the generation of clonal cell lines, we developed a rapid system that relies on the expression of the TAP-tagged bait protein from an episomally maintained plasmid based on pMEP4 (Invitrogen). Expression of tagged murine eIF4E from this plasmid was controlled using the cadmium chloride inducible metallothionein promoter. Lysis of the expressing cells and subsequent affinity purification via binding to rabbit IgG agarose, TEV protease cleavage, binding to streptavidin linked agarose and subsequent biotin elution identified numerous

  14. Easy and Rapid Purification of Highly Active Nisin

    Directory of Open Access Journals (Sweden)

    André Abts


    Full Text Available Nisin is an antimicrobial peptide produced and secreted by several L. lactis strains and is specifically active against Gram-positive bacteria. In previous studies, nisin was purified via cation exchange chromatography at low pH employing a single-step elution using 1 M NaCl. Here, we describe an optimized purification protocol using a five-step NaCl elution to remove contaminants. The obtained nisin is devoid of impurities and shows high bactericidal activity against the nisin-sensitive L. lactis strain NZ9000. Purified nisin exhibits an IC50 of ~3 nM, which is a tenfold improvement as compared to nisin obtained via the one-step elution procedure.

  15. Purification and Characterization of An Alkaline Protease from Acetes chinensis

    Institute of Scientific and Technical Information of China (English)

    XU Jiachao; LIU Xin; LI Zhaojie; XU Jie; XUE Changhu; GAO Xin


    An alkaline protease from Acetes chinensis was purified and characterized in this study. The steps of purification include ammonium sulfate precipitation, ion-exchange chromatography with Q-sepharose Fast Flow, gel filtration chromatography with S300 and the second ion-exchange chromatography with Q-sepharose Fast Flow. The protease was isolated and purified, which was present and active on protein substrates (azocasein and casein). The specific protease activity was 17.15folds and the recovery was 4.67. The molecular weight of the protease was estimated at 23.2 kD by SDS-PAGE. With azocasein as the susbstrate, the optimal temperature was 55 ℃ and the optimal pH value was 5.5. Ion Ca2+ could enhance the proteolytic activity of the protease, while Cu2+ , EDTA and PMSF could inhibit its activity.

  16. Purification Of Water From Nsukka Water Pond Using Solar Still.

    Directory of Open Access Journals (Sweden)

    Ugwuoke E.C


    Full Text Available Abstract This work presents the analysis of a solar water distillation system. There is important need for good drinking water in the world today due to harmful effect of water borne diseases. Most water from rivers ponds seas are either salty or brackish and require purification before drinking. The water used in this work is collected from pond at Nsukka Urban and the experiment was performed at University of Nigeria Nsukka. Twenty litres of water was used for the experiment and 4 litres was obtained as the maximum volume after 10 days .The average temperature recorded during the experiment was 29C. The chemical and physical properties of the distillate correspond to world Health Organization Standard.

  17. Stability, purification, and applications of bromelain: A review. (United States)

    de Lencastre Novaes, Letícia Celia; Jozala, Angela Faustino; Lopes, André Moreni; de Carvalho Santos-Ebinuma, Valéria; Mazzola, Priscila Gava; Pessoa Junior, Adalberto


    Bromelain is a cysteine protease found in pineapple tissue. Because of its anti-inflammatory and anti-cancer activities, as well as its ability to induce apoptotic cell death, bromelain has proved useful in several therapeutic areas. The market for this protease is growing, and several studies exploring various properties of this molecule have been reported. This review aims to compile this data, and summarize the main findings on bromelain in the literature to date. The physicochemical properties and stability of bromelain under different conditions are discussed. Several studies on the purification of bromelain from crude extracts using a wide range of techniques such as liquid-liquid extractions by aqueous two-phase system, ultrafiltration, precipitation, and chromatography, have been reported. Finally, the various applications of bromelain are presented. This review therefore covers the main properties of bromelain, aiming to provide an up-to-date compilation of the data reported on this enzyme.

  18. New process of silicon carbide purification intended for silicon passivation (United States)

    Barbouche, M.; Zaghouani, R. Benabderrahmane; Benammar, N. E.; Aglieri, V.; Mosca, M.; Macaluso, R.; Khirouni, K.; Ezzaouia, H.


    In this work, we report on a new, efficient and low cost process of silicon carbide (SiC) powder purification intended to be used in photovoltaic applications. This process consists on the preparation of porous silicon carbide layers followed by a photo-thermal annealing under oxygen atmosphere and chemical treatment. The effect of etching time on impurities removal efficiency was studied. Inductively coupled plasma atomic emission spectrometry (ICP-AES) results showed that the best result was achieved for an etching time of 10 min followed by gettering at 900 °C during 1 h. SiC purity is improved from 3N (99.9771%) to 4N (99.9946%). Silicon carbide thin films were deposited onto silicon substrates by pulsed laser deposition technique (PLD) using purified SiC powder as target. Significant improvement of the minority carrier lifetime was obtained encouraging the use of SiC as a passivation layer for silicon.

  19. Matrix product purifications for canonical ensembles and quantum number distributions (United States)

    Barthel, Thomas


    Matrix product purifications (MPPs) are a very efficient tool for the simulation of strongly correlated quantum many-body systems at finite temperatures. When a system features symmetries, these can be used to reduce computation costs substantially. It is straightforward to compute an MPP of a grand-canonical ensemble, also when symmetries are exploited. This paper provides and demonstrates methods for the efficient computation of MPPs of canonical ensembles under utilization of symmetries. Furthermore, we present a scheme for the evaluation of global quantum number distributions using matrix product density operators (MPDOs). We provide exact matrix product representations for canonical infinite-temperature states, and discuss how they can be constructed alternatively by applying matrix product operators to vacuum-type states or by using entangler Hamiltonians. A demonstration of the techniques for Heisenberg spin-1 /2 chains explains why the difference in the energy densities of canonical and grand-canonical ensembles decays as 1 /L .

  20. Purification and characterisation of antigenic gliadins in coeliac disease. (United States)

    Sjöström, H; Friis, S U; Norén, O; Anthonsen, D


    Two gliadins, known to be especially antigenic in coeliac disease, were purified to homogeneity by a series of ion-exchange chromatography steps. Their N-terminal amino acid sequences showed minor differences but clearly classified them as gamma-type gliadins. The purified gliadins were further characterised with respect to amino acid composition, molecular mass and E1(1%)cm at 276 nm. Based on these properties it is suggested that one of them is identical to a gamma-type gliadin, earlier characterised by its nucleotide sequence, whereas the other has not previously been described. The purification procedure may form the basis for the development of a more differentiated analysis of circulating antibodies for diagnosis and makes clinical testing of the toxicity of defined gliadin peptides feasible.