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Sample records for membrane introduction mass

  1. Membrane introduction proton-transfer-reaction mass spectrometry

    International Nuclear Information System (INIS)

    Alexander, M.; Boscaini, E.; Maerk, T.; Lindinger, W.

    2002-01-01

    Proton-transfer-reaction mass spectrometry (PTR-MS) is a rapidly expanding field with multiple applications in ion physics, atmospheric chemistry, food chemistry, volatile organic compounds monitoring and biology. Initial studies that combine PTR-MS and membrane introduction mass spectrometry (MIMS) were researched and outlined. First using PTR-MS, certain fundamental physical properties of a poly-dimethylsiloxane (PDMS) membrane including solubilities and diffusion coefficients were measured. Second, it was shown how the chemical selectivity of the (PDMS) can be used to extend the capabilities of the PTR-MS instrument by eliminating certain isobaric interferences and excluding water from volatile organic compounds (VOCs). Experiments with mixtures of several VOCs (toluene, benzene, acetone, propanal, methanol) are presented. (nevyjel)

  2. Development of novel nano-composite membranes as introduction systems for mass spectrometers: Contrasting nano-composite membranes and conventional inlet systems

    Science.gov (United States)

    Miranda, Luis Diego

    This dissertation presents the development of novel nano-composite membranes as introduction systems for mass spectrometers. These nano-composite membranes incorporate anodic aluminum oxide (AAO) membranes as templates that can be used by themselves or modified by a variety of chemical deposition processes. Two types of nano-composite membranes are presented. The first nano-composite membrane has carbon deposited within the pores of an AAO membrane. The second nano-composite membrane is made by coating an AAO membrane with a thin polymer film. The following chapters describe the transmission properties these nano-composite membranes and compare them to conventional mass spectrometry introduction systems. The nano- composite membranes were finally coupled to the inlet system of an underwater mass spectrometer revealing their utility in field deployments.

  3. Measurement of spatial and temporal variation in volatile hazardous air pollutants in Tacoma, Washington, using a mobile membrane introduction mass spectrometry (MIMS) system.

    Science.gov (United States)

    Davey, Nicholas G; Fitzpatrick, Cole T E; Etzkorn, Jacob M; Martinsen, Morten; Crampton, Robert S; Onstad, Gretchen D; Larson, Timothy V; Yost, Michael G; Krogh, Erik T; Gilroy, Michael; Himes, Kathy H; Saganić, Erik T; Simpson, Christopher D; Gill, Christopher G

    2014-09-19

    The objective of this study was to use membrane introduction mass spectrometry (MIMS), implemented on a mobile platform, in order to provide real-time, fine-scale, temporally and spatially resolved measurements of several hazardous air pollutants. This work is important because there is now substantial evidence that fine-scale spatial and temporal variations of air pollutant concentrations are important determinants of exposure to air pollution and adverse health outcomes. The study took place in Tacoma, WA during periods of impaired air quality in the winter and summer of 2008 and 2009. Levels of fine particles were higher in winter compared to summer, and were spatially uniform across the study area. Concentrations of vapor phase pollutants measured by membrane introduction mass spectrometry (MIMS), notably benzene and toluene, had relatively uniform spatial distributions at night, but exhibited substantial spatial variation during the day-daytime levels were up to 3-fold higher at traffic-impacted locations compared to a reference site. Although no direct side-by-side comparison was made between the MIMS system and traditional fixed site monitors, the MIMS system typically reported higher concentrations of specific VOCs, particularly benzene, ethylbenzene and naphthalene, compared to annual average concentrations obtained from SUMA canisters and gas chromatographic analysis at the fixed sites.

  4. Mobile membrane introduction tandem mass spectrometry for on-the-fly measurements and adaptive sampling of VOCs around oil and gas projects in Alberta, Canada

    Science.gov (United States)

    Krogh, E.; Gill, C.; Bell, R.; Davey, N.; Martinsen, M.; Thompson, A.; Simpson, I. J.; Blake, D. R.

    2012-12-01

    The release of hydrocarbons into the environment can have significant environmental and economic consequences. The evolution of smaller, more portable mass spectrometers to the field can provide spatially and temporally resolved information for rapid detection, adaptive sampling and decision support. We have deployed a mobile platform membrane introduction mass spectrometer (MIMS) for the in-field simultaneous measurement of volatile and semi-volatile organic compounds. In this work, we report instrument and data handling advances that produce geographically referenced data in real-time and preliminary data where these improvements have been combined with high precision ultra-trace VOCs analysis to adaptively sample air plumes near oil and gas operations in Alberta, Canada. We have modified a commercially available ion-trap mass spectrometer (Griffin ICX 400) with an in-house temperature controlled capillary hollow fibre polydimethylsiloxane (PDMS) polymer membrane interface and in-line permeation tube flow cell for a continuously infused internal standard. The system is powered by 24 VDC for remote operations in a moving vehicle. Software modifications include the ability to run continuous, interlaced tandem mass spectrometry (MS/MS) experiments for multiple contaminants/internal standards. All data are time and location stamped with on-board GPS and meteorological data to facilitate spatial and temporal data mapping. Tandem MS/MS scans were employed to simultaneously monitor ten volatile and semi-volatile analytes, including benzene, toluene, ethylbenzene and xylene (BTEX), reduced sulfur compounds, halogenated organics and naphthalene. Quantification was achieved by calibrating against a continuously infused deuterated internal standard (toluene-d8). Time referenced MS/MS data were correlated with positional data and processed using Labview and Matlab to produce calibrated, geographical Google Earth data-visualizations that enable adaptive sampling protocols

  5. Coronal Mass Ejections An Introduction

    CERN Document Server

    Howard, Timothy

    2011-01-01

    In times of growing technological sophistication and of our dependence on electronic technology, we are all affected by space weather. In its most extreme form, space weather can disrupt communications, damage and destroy spacecraft and power stations, and increase radiation exposure to astronauts and airline passengers. Major space weather events, called geomagnetic storms, are large disruptions in the Earth’s magnetic field brought about by the arrival of enormous magnetized plasma clouds from the Sun. Coronal mass ejections (CMEs) contain billions of tons of plasma and hurtle through space at speeds of several million miles per hour. Understanding coronal mass ejections and their impact on the Earth is of great interest to both the scientific and technological communities. This book provides an introduction to coronal mass ejections, including a history of their observation and scientific revelations, instruments and theory behind their detection and measurement, and the status quo of theories describing...

  6. Introduction to solid supported membrane based electrophysiology.

    Science.gov (United States)

    Bazzone, Andre; Costa, Wagner Steuer; Braner, Markus; Călinescu, Octavian; Hatahet, Lina; Fendler, Klaus

    2013-05-11

    The electrophysiological method we present is based on a solid supported membrane (SSM) composed of an octadecanethiol layer chemisorbed on a gold coated sensor chip and a phosphatidylcholine monolayer on top. This assembly is mounted into a cuvette system containing the reference electrode, a chlorinated silver wire. After adsorption of membrane fragments or proteoliposomes containing the membrane protein of interest, a fast solution exchange is used to induce the transport activity of the membrane protein. In the single solution exchange protocol two solutions, one non-activating and one activating solution, are needed. The flow is controlled by pressurized air and a valve and tubing system within a faraday cage. The kinetics of the electrogenic transport activity is obtained via capacitive coupling between the SSM and the proteoliposomes or membrane fragments. The method, therefore, yields only transient currents. The peak current represents the stationary transport activity. The time dependent transporter currents can be reconstructed by circuit analysis. This method is especially suited for prokaryotic transporters or eukaryotic transporters from intracellular membranes, which cannot be investigated by patch clamp or voltage clamp methods.

  7. Mass transport in thin supported silica membranes

    NARCIS (Netherlands)

    Benes, Nieck Edwin

    2000-01-01

    In this thesis multi-component mass transport in thin supported amorphous silica membranes is discussed. These membranes are micro-porous, with pore diameters smaller than 4Å and show high fluxes for small molecules (such as hydrogen) combined with high selectivities for these molecules with respect

  8. Introduction to models of neutrino masses and mixings

    International Nuclear Information System (INIS)

    Joshipura, Anjan S.

    2004-01-01

    This review contains an introduction to models of neutrino masses for non-experts. Topics discussed are i) different types of neutrino masses ii) structure of neutrino masses and mixing needed to understand neutrino oscillation results iii) mechanism to generate neutrino masses in gauge theories and iv) discussion of generic scenarios proposed to realize the required neutrino mass structures. (author)

  9. Membrane computing: brief introduction, recent results and applications.

    Science.gov (United States)

    Păun, Gheorghe; Pérez-Jiménez, Mario J

    2006-07-01

    The internal organization and functioning of living cells, as well as their cooperation in tissues and higher order structures, can be a rich source of inspiration for computer science, not fully exploited at the present date. Membrane computing is an answer to this challenge, well developed at the theoretical (mathematical and computability theory) level, already having several applications (via usual computers), but without having yet a bio-lab implementation. After briefly discussing some general issues related to natural computing, this paper provides an informal introduction to membrane computing, focused on the main ideas, the main classes of results and of applications. Then, three recent achievements, of three different types, are briefly presented, with emphasis on the usefulness of membrane computing as a framework for devising models of interest for biological and medical research.

  10. Radiation-induced Mass Transfer through Membranes

    Czech Academy of Sciences Publication Activity Database

    Levdansky, V.V.; Smolík, Jiří; Moravec, Pavel

    2009-01-01

    Roč. 36, č. 2 (2009), s. 125-128 ISSN 0735-1933 R&D Projects: GA AV ČR(CZ) IAA400720804 Institutional research plan: CEZ:AV0Z40720504 Keywords : mass transfer * adiation * membrane Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.189, year: 2009

  11. Introduction to mass spectrometry-based proteomics

    DEFF Research Database (Denmark)

    Matthiesen, R.; Bunkenborg, J.

    2013-01-01

    Mass spectrometry has been widely applied to study biomolecules and one rapidly developing field is the global analysis of proteins, proteomics. Understanding and handling mass spectrometry data is a multifaceted task that requires many decisions to be made to get the most comprehensive informati...

  12. Mass Communication: An Introduction; Theory and Practice of Mass Media in Society.

    Science.gov (United States)

    Bittner, John R.

    From the perspectives of historical, contemporary, and future interpretations of mass communication, this introduction to the theory and practice of mass media in society treats both the social context of mass communication and the hardware components that make it operable. The book discusses all mass media--newspapers, magazines, radio,…

  13. Introduction to computational mass transfer with applications to chemical engineering

    CERN Document Server

    Yu, Kuo-Tsung

    2017-01-01

    This book offers an easy-to-understand introduction to the computational mass transfer (CMT) method. On the basis of the contents of the first edition, this new edition is characterized by the following additional materials. It describes the successful application of this method to the simulation of the mass transfer process in a fluidized bed, as well as recent investigations and computing methods for predictions for the multi-component mass transfer process. It also demonstrates the general issues concerning computational methods for simulating the mass transfer of the rising bubble process. This new edition has been reorganized by moving the preparatory materials for Computational Fluid Dynamics (CFD) and Computational Heat Transfer into appendices, additions of new chapters, and including three new appendices on, respectively, generalized representation of the two-equation model for the CMT, derivation of the equilibrium distribution function in the lattice-Boltzmann method, and derivation of the Navier-S...

  14. Introduction

    OpenAIRE

    Brake, Laurel; Mussell, James

    2013-01-01

    When W. T. Stead died on the Titanic he was the most famous Englishman on board. A mass of contradictions and a crucial figure in the history of the British press, Stead was a towering presence in the cultural life of late-Victorian and Edwardian society. In this introduction, we consider Stead as a ‘mass of contradictions’ and offer a few ways in which his prodigious output and activity might be understood.

  15. Introduction

    Directory of Open Access Journals (Sweden)

    Laurel Brake

    2013-04-01

    mso-fareast-language:JA;} When W. T. Stead died on the 'Titanic' he was the most famous Englishman on board. A mass of contradictions and a crucial figure in the history of the British press, Stead was a towering presence in the cultural life of late-Victorian and Edwardian society. In this introduction, we consider Stead as a ‘mass of contradictions’ and offer a few ways in which his prodigious output and activity might be understood.

  16. Membranes for nanometer-scale mass fast transport

    Science.gov (United States)

    Bakajin, Olgica [San Leandro, CA; Holt, Jason [Berkeley, CA; Noy, Aleksandr [Belmont, CA; Park, Hyung Gyu [Oakland, CA

    2011-10-18

    Nanoporous membranes comprising single walled, double walled, and multiwalled carbon nanotubes embedded in a matrix material were fabricated for fluid mechanics and mass transfer studies on the nanometer scale and commercial applications. Average pore size can be 2 nm to 20 nm, or seven nm or less, or two nanometers or less. The membrane can be free of large voids spanning the membrane such that transport of material such as gas or liquid occurs exclusively through the tubes. Fast fluid, vapor, and liquid transport are observed. Versatile micromachining methods can be used for membrane fabrication. A single chip can comprise multiple membranes. These membranes are a robust platform for the study of confined molecular transport, with applications in liquid and gas separations and chemical sensing including desalination, dialysis, and fabric formation.

  17. Determination of the gas-to-membrane mass transfer coefficient in a catalytic membrane reactor

    NARCIS (Netherlands)

    Veldsink, J.W.; Versteeg, G.F.; Swaaij, W.P.M. van

    1995-01-01

    A novel method to determine the external mass transfer coefficient in catalytic membrane reactors (Sloot et al., 1992a, b) was presented in this study. In a catalytically active membrane reactor, in which a very fast reaction occurs, the external transfer coefficient can conveniently be measured by

  18. Black hole mass formula in the membrane paradigm

    Science.gov (United States)

    Lemos, José P. S.; Zaslavskii, Oleg B.

    2018-03-01

    The membrane paradigm approach adopts a timelike surface, stretched out off the null event horizon, to study several important black hole properties. We use this powerful tool to give a direct derivation of the black hole mass formula in the static and stationary cases without and with electric field. Since here the membrane is a self-gravitating material system, we go beyond the usual applicability on test particles and test fields of the paradigm.

  19. Temperature-programmed desorption for membrane inlet mass spectrometry

    DEFF Research Database (Denmark)

    Ketola, R.A.; Grøn, C.; Lauritsen, F.R.

    1998-01-01

    We present a novel technique for analyzing volatile organic compounds in air samples using a solid adsorbent together with temperature-programmed desorption and subsequent detection by membrane inlet mass spectrometry (TPD-MIMS). The new system has the advantage of a fast separation of compounds...... to diffuse through the membrane into the mass spectrometer in a few seconds. In this fashion we could completely separate many similar volatile compounds, for example toluene from xylene and trichloroethene from tetrachloroethene. Typical detection limits were at low or sub-nanogram levels, the dynamic range...

  20. RESEARCH OF THE MASS TRANSFER AT MEMBRANE CLEANING OF BIOGAZ

    Directory of Open Access Journals (Sweden)

    Marat SATAYEV

    2015-04-01

    Full Text Available Everyone has long known the benefits and effectiveness of biogas. Particularly, getting biogas from the agricultural waste is very promising. But, the question is if we can use such a useful and effective biogas at 100%. Today, we use only a half of the benefit, because to get the biogas we spend more energy than we get. In this regard, the work on the study of the biogas development is extremely important. The study of the biogas formation requires numerous experiments. This article analyzes the biogas mass transfer with the membrane purification and identification of the of mass transfer mechanisms through the membrane pores.

  1. Introduction to the concept of added mass in fluid mechanics

    International Nuclear Information System (INIS)

    Pham Dan Tam.

    1977-07-01

    The physical phenomenum which leads to the concept of added mass for an inviscid fluid is recalled. The added-mass tensor for a solid body moving through an unbounded fluid is defined and some of its properties are presented. The Taylor theorem is exposed, which enables some of the tensor components to be analytically derived in particular cases. Added-mass values are provided for bodies of particular shape. Applications of the added-mass concept to different problems are given [fr

  2. Mathematical modeling of water mass balance for proton exchange membrane fuel cell

    International Nuclear Information System (INIS)

    Wan Ramli Wan Daud; Kamaruzzaman Sopian; Jaafar Sahari; Nik Suhaimi Mat Hassan

    2006-01-01

    Gas and water management are key to achieving good performance from a proton exchange membrane fuel cell (PEMFC) stack. Water plays a critical role in PEMFC. The proton conductivity is increase with the water content. In order to achieve enough hydration, water is normally introduced into the cell externally by a variety of methods such as liquid injection, steam introduction, and humidification of reactants by passing them through humidifiers before entering the cell. In this paper, mathematical modeling of water mass balance for PEMFC at anode and cathode side are proposed by using external humidification and assume that steady state, constant pressure, constant temperature and gases distribution are uniform

  3. Introduction

    DEFF Research Database (Denmark)

    Kørnøv, Lone; Lund, Henrik; Remmen, Arne

    2004-01-01

    The chapter gives an introduction to the book "Environmental planning and management : tools for a sustainable development".......The chapter gives an introduction to the book "Environmental planning and management : tools for a sustainable development"....

  4. Introduction

    DEFF Research Database (Denmark)

    Høgfeldt Hansen, Leif

    2016-01-01

    This introduction to South Korean architecture gives an overall view of the architecture done in the country in historic times as well as a general introduction to the culture of the country.......This introduction to South Korean architecture gives an overall view of the architecture done in the country in historic times as well as a general introduction to the culture of the country....

  5. Ultrananocrystalline Diamond Membranes for Detection of High-Mass Proteins

    Science.gov (United States)

    Kim, H.; Park, J.; Aksamija, Z.; Arbulu, M.; Blick, R. H.

    2016-12-01

    Mechanical resonators realized on the nanoscale by now offer applications in mass sensing of biomolecules with extraordinary sensitivity. The general idea is that perfect mechanical mass sensors should be of extremely small size to achieve zepto- or yoctogram sensitivity in weighing single molecules similar to a classical scale. However, the small effective size and long response time for weighing biomolecules with a cantilever restricts their usefulness as a high-throughput method. Commercial mass spectrometry (MS), on the other hand, such as electrospray ionization and matrix-assisted laser desorption and ionization (MALDI) time of flight (TOF) and their charge-amplifying detectors are the gold standards to which nanomechanical resonators have to live up to. These two methods rely on the ionization and acceleration of biomolecules and the following ion detection after a mass selection step, such as TOF. The principle we describe here for ion detection is based on the conversion of kinetic energy of the biomolecules into thermal excitation of chemical vapor deposition diamond nanomembranes via phonons followed by phonon-mediated detection via field emission of thermally emitted electrons. We fabricate ultrathin diamond membranes with large lateral dimensions for MALDI TOF MS of high-mass proteins. These diamond membranes are realized by straightforward etching methods based on semiconductor processing. With a minimal thickness of 100 nm and cross sections of up to 400 ×400 μ m2 , the membranes offer extreme aspect ratios. Ion detection is demonstrated in MALDI TOF analysis over a broad range from insulin to albumin. The resulting data in detection show much enhanced resolution as compared to existing detectors, which can offer better sensitivity and overall performance in resolving protein masses.

  6. Mass and Heat Transfer Analysis of Membrane Humidifier with a Simple Lumped Mass Model

    International Nuclear Information System (INIS)

    Lee, Young Duk; Bae, Ho June; Ahn, Kook Young; Yu, Sang Seok; Hwang, Joon Young

    2009-01-01

    The performance of proton exchange membrane fuel cell (PEMFC) is seriously changed by the humidification condition which is intrinsic characteristics of the PEMFC. Typically, the humidification of fuel cell is carried out with internal or external humidifier. A membrane humidifier is applied to the external humidification of residential power generation fuel cell due to its convenience and high performance. In this study, a simple static model is constructed to understand the physical phenomena of the membrane humidifier in terms of geometric parameters and operating parameters. The model utilizes the concept of shell and tube heat exchanger but the model is also able to estimate the mass transport through the membrane. Model is constructed with FORTRAN under Matlab/Simulink □ environment to keep consistency with other components model which we already developed. Results shows that the humidity of wet gas and membrane thickness are critical parameters to improve the performance of the humidifier

  7. An introduction to mass cytometry: fundamentals and applications.

    Science.gov (United States)

    Tanner, Scott D; Baranov, Vladimir I; Ornatsky, Olga I; Bandura, Dmitry R; George, Thaddeus C

    2013-05-01

    Mass cytometry addresses the analytical challenges of polychromatic flow cytometry by using metal atoms as tags rather than fluorophores and atomic mass spectrometry as the detector rather than photon optics. The many available enriched stable isotopes of the transition elements can provide up to 100 distinguishable reporting tags, which can be measured simultaneously because of the essential independence of detection provided by the mass spectrometer. We discuss the adaptation of traditional inductively coupled plasma mass spectrometry to cytometry applications. We focus on the generation of cytometry-compatible data and on approaches to unsupervised multivariate clustering analysis. Finally, we provide a high-level review of some recent benchmark reports that highlight the potential for massively multi-parameter mass cytometry.

  8. Introduction to computational mass transfer with applications to chemical engineering

    CERN Document Server

    Yu, Kuo-Tsong

    2014-01-01

    This book presents a new computational methodology called Computational Mass Transfer (CMT). It offers an approach to rigorously simulating the mass, heat and momentum transfer under turbulent flow conditions with the help of two newly published models, namely the C’2—εC’ model and the Reynolds  mass flux model, especially with regard to predictions of concentration, temperature and velocity distributions in chemical and related processes. The book will also allow readers to understand the interfacial phenomena accompanying the mass transfer process and methods for modeling the interfacial effect, such as the influences of Marangoni convection and Rayleigh convection. The CMT methodology is demonstrated by means of its applications to typical separation and chemical reaction processes and equipment, including distillation, absorption, adsorption and chemical reactors. Professor Kuo-Tsong Yu is a Member of the Chinese Academy of Sciences. Dr. Xigang Yuan is a Professor at the School of Chemical Engine...

  9. Introduction of functionalizable groups via radiation grafting into polymer electrolyte membranes for fuel cells

    International Nuclear Information System (INIS)

    Buchmueller, Y.; Scherer, G.G.; Wokaun, A.; Gubler, L.

    2011-01-01

    Complete text of publication follows. Our work is focused on the introduction of functionalizable groups, so called linkers, to polymer electrolyte membranes. The aim is to attach antioxidant groups to the linkers to enhance the durability of the proton conducting membrane in a fuel cell. The synthetic route we chose is radiation cografting of functionalizable monomers and precursor monomers of a protogenic group into ETFE base film (thickness 25 μm) with subsequent amination. Typically, we performed cografting of styrene with different linkers, such as acryloyl chloride, vinylbenzyl chloride, and glycidyl methacrylate. Styrene is readily sulfonated to introduce proton conductivity. The cografting behavior of the linkers and styrene was investigated to target the desired molar fraction of the monomers in the grafted polymer. All films were characterized by Fourier transform infrared (FTIR) spectroscopy and elemental analysis. Using these data the graft polymerization kinetics of these systems have been determined. The cografted films were first functionalized with amines, such as thyramine and dopamine, and then sulfonated or vice-versa, depending on the stability of the compounds in acidic environment. The synthesized membranes were characterized for conductivity and ion exchange capacity (IEC). Promising membranes were tested in a fuel cell.

  10. Membrane Inlet Mass Spectrometry for Homeland Security and Forensic Applications

    Science.gov (United States)

    Giannoukos, Stamatios; Brkić, Boris; Taylor, Stephen; France, Neil

    2015-02-01

    A man-portable membrane inlet mass spectrometer has been built and tested to detect and monitor characteristic odors emitted from the human body and also from threat substances. In each case, a heated membrane sampling probe was used. During human scent monitoring experiments, data were obtained for inorganic gases and volatile organic compounds emitted from human breath and sweat in a confined space. Volatile emissions were detected from the human body at low ppb concentrations. Experiments with compounds associated with narcotics, explosives, and chemical warfare agents were conducted for a range of membrane types. Test compounds included methyl benzoate (odor signature of cocaine), piperidine (precursor in clandestine phencyclidine manufacturing processes), 2-nitrotoluene (breakdown product of TNT), cyclohexanone (volatile signature of plastic explosives), dimethyl methylphosphonate (used in sarin and soman nerve agent production), and 2-chloroethyl ethyl sulfide (simulant compound for sulfur mustard gas). Gas phase calibration experiments were performed allowing sub-ppb LOD to be established. The results showed excellent linearity versus concentration and rapid membrane response times.

  11. Detecting Extracellular Carbonic Anhydrase Activity Using Membrane Inlet Mass Spectrometry

    Science.gov (United States)

    Delacruz, Joannalyn; Mikulski, Rose; Tu, Chingkuang; Li, Ying; Wang, Hai; Shiverick, Kathleen T.; Frost, Susan C.; Horenstein, Nicole A.; Silverman, David N.

    2010-01-01

    Current research into the function of carbonic anhydrases in cell physiology emphasizes the role of membrane-bound carbonic anhydrases, such as carbonic anhydrase IX that has been identified in malignant tumors and is associated with extracellular acidification as a response to hypoxia. We present here a mass spectrometric method to determine the extent to which total carbonic anhydrase activity is due to extracellular carbonic anhydrase in whole cell preparations. The method is based on the biphasic rate of depletion of 18O from CO2 measured by membrane inlet mass spectrometry. The slopes of the biphasic depletion are a sensitive measure of the presence of carbonic anhydrase outside and inside of the cells. This property is demonstrated here using suspensions of human red cells in which external carbonic anhydrase was added to the suspending solution. It is also applied to breast and prostate cancer cells which both express exofacial carbonic anhydrase IX. Inhibition of external carbonic anhydrase is achieved by use of a membrane impermeant inhibitor that was synthesized for this purpose, p-aminomethylbenzenesulfonamide attached to a polyethyleneglycol polymer. PMID:20417171

  12. Introduction

    DEFF Research Database (Denmark)

    Jensen, Rasmus Thybo; Moran, Dermot

    2012-01-01

    An introduction to a special issue of Phenomenology and the Cognitive Sciences dedicated to empathy and the direct perception approach to other minds......An introduction to a special issue of Phenomenology and the Cognitive Sciences dedicated to empathy and the direct perception approach to other minds...

  13. Introduction

    DEFF Research Database (Denmark)

    Søbjerg, Lene Mosegaard

    2016-01-01

    Introduction to anthology which provides the theoretical basis of an Erasmus+ project involving marginalised young people, practitioners, students and academics in co-creating a teaching module for the social professions.......Introduction to anthology which provides the theoretical basis of an Erasmus+ project involving marginalised young people, practitioners, students and academics in co-creating a teaching module for the social professions....

  14. Introduction

    International Nuclear Information System (INIS)

    Kadirov, A.Kh.; Khaydarov, K.Kh.; Giyosov, A.Sh.

    2000-01-01

    In the introduction authors describe book in general and in particular describe the ways and methods of direct synthesis on the base of different derivatives of cholanic acids and receiving of line of corresponding ethers which have practical properties

  15. Introduction

    DEFF Research Database (Denmark)

    Henkel, Anna; Åkerstrøm Andersen, Niels

    2015-01-01

    An introduction is presented in which the authors discuss various reports within the issue on topics including the concept of responsibility, the discourse about responsibility, and the attribution of responsibility in an interdisciplinary context.......An introduction is presented in which the authors discuss various reports within the issue on topics including the concept of responsibility, the discourse about responsibility, and the attribution of responsibility in an interdisciplinary context....

  16. Mass Spectrometry of Polymer Electrolyte Membrane Fuel Cells

    Directory of Open Access Journals (Sweden)

    Viktor Johánek

    2016-01-01

    Full Text Available The chemical analysis of processes inside fuel cells under operating conditions in either direct or inverted (electrolysis mode and their correlation with potentiostatic measurements is a crucial part of understanding fuel cell electrochemistry. We present a relatively simple yet powerful experimental setup for online monitoring of the fuel cell exhaust (of either cathode or anode side downstream by mass spectrometry. The influence of a variety of parameters (composition of the catalyst, fuel type or its concentration, cell temperature, level of humidification, mass flow rate, power load, cell potential, etc. on the fuel cell operation can be easily investigated separately or in a combined fashion. We demonstrate the application of this technique on a few examples of low-temperature (70°C herein polymer electrolyte membrane fuel cells (both alcohol- and hydrogen-fed subjected to a wide range of conditions.

  17. Performance Improvement of Membrane Stress Measurement Equipment through Evaluation of Added Mass of Membrane and Error Correction

    Directory of Open Access Journals (Sweden)

    Sang-Wook Jin

    2017-01-01

    Full Text Available One of the most important issues in keeping membrane structures in stable condition is to maintain the proper stress distribution over the membrane. However, it is difficult to determine the quantitative real stress level in the membrane after the completion of the structure. The stress relaxation phenomenon of the membrane and the fluttering effect due to strong wind or ponding caused by precipitation may cause severe damage to the membrane structure itself. Therefore, it is very important to know the magnitude of the existing stress in membrane structures for their maintenance. The authors have proposed a new method for separately estimating the membrane stress in two different directions using sound waves instead of directly measuring the membrane stress. The new method utilizes the resonance phenomenon of the membrane, which is induced by sound excitations given through an audio speaker. During such experiment, the effect of the surrounding air on the vibrating membrane cannot be overlooked in order to assure high measurement precision. In this paper, an evaluation scheme for the added mass of membrane with the effect of air on the vibrating membrane and the correction of measurement error is discussed. In addition, three types of membrane materials are used in the experiment in order to verify the expandability and accuracy of the membrane measurement equipment.

  18. Introduction

    DEFF Research Database (Denmark)

    Ashbee, Edward; Dumbrell, John

    2017-01-01

    The introduction sets a framework for subsequent chapters by considering theories of change and the extent to which there was consequential change during the Obama years. It draws upon earlier scholarship to suggest that although there certainly was no “transformation” (when new interests secure...... Congress. Nonetheless, although recent literature within historical institutionalism has stressed the importance of incrementalism, it is vulnerable to rollback. Against this background, the introduction sets questions about the character of change that are addressed in the case studies included...

  19. Introduction

    DEFF Research Database (Denmark)

    Gjerdrum Pedersen, Esben Rahbek; Thusgaard Pedersen, Janni

    2013-01-01

    An introduction is presented in which the editors discuss various reports within the issue on topics including the shared value concept in the education and business, the role of corporate foundations in establishing cross-sector partnerships, and the mechanisms of governance in the cross...

  20. Introduction

    DEFF Research Database (Denmark)

    Pop, Paul; Alistar, Mirela; Stuart, Elena

    2015-01-01

    This chapter presents an introduction to the microfluidics field and microfluidic biochips. We discuss the main fluid propulsion principles used by modern microfluidic platforms, with a focus on “digital” microfluidic biochips, which are the topic of this book. Digital microfluidic biochips...

  1. Introduction

    DEFF Research Database (Denmark)

    Barwell, Richard; Clarkson, Philip; Halai, Anjum

    2016-01-01

    This chapter provides the introduction to this ICMI Study 21 volume. It includes: a discussion of the place of this study and its topic within ICME; a discussion of what is meant by the study title; and a brief historical account of research on this topic in mathematics education. The chapter also...

  2. Introduction

    DEFF Research Database (Denmark)

    Schmidt, Johannes Dragsbæk; Berg, Torsten Rødel

    2012-01-01

    The chapter includes a discussion about the play by Henrik Ibsen from 1879, A Doll's House, how it still proves to be relevant today to gender relations not only in Denmark but in Nepal as well. The introduction explains how Ibsen's play inspired two theater directors from Denmark and Nepal...

  3. Introduction

    International Nuclear Information System (INIS)

    Raeder, J.

    1975-01-01

    The introduction to this monography gives a brief survey of the history of the MHD generator, outlines the fundamental questioning of the research concerned and then deals with the combustion gas MHD generator research programme of the working society MPI for plasma physics (IPP)/Maschinenfabrik Augsburg-Nuernberg AG (M.A.N.). (GG/LH) [de

  4. Introduction

    NARCIS (Netherlands)

    Dieci, R.; He, X.-Z.; Hommes, C.; Dieci, R.; He, X.-Z.; Hommes, C.

    2014-01-01

    This introduction summarises the main contributions of 18 chapters in this book, in addition to two articles (Part I) reflecting Carl's view on a broad range of research-related issues originally published in Italian. The contributed chapters cover the latest developments in Nonlinear Economic

  5. Introduction

    NARCIS (Netherlands)

    Doreian, Patrick; Stokman, Frans N.

    2001-01-01

    Introduction to: The proceedings of a conference that was held on the analysis of repeated cross sections at the University of Nijmegen on June 15±16, 2000. This two-days meeting was attended by 75 participants from seven different countries (AUS, B, F, GER, NL, USA, UK) and from a wide array of

  6. Introduction

    NARCIS (Netherlands)

    Salverda, W.; Nolan, B.; Checchi, D.; Marx, I.; McKnight, A.; Tóth, I.G.; van de Werfhorst, H.; Salverda, W.; Nolan, B.; Checchi, D.; Marx, I.; McKnight, A.; Tóth, I.G.; van de Werfhorst, H.

    2014-01-01

    This chapter provides the introduction to a collection of 11 comparative chapters and a concluding chapter which, based on 30 country studies (25 European, USA, Canada, Australia, Japan, Korea; reported in the companion volume Nolan et al. 2013), look at the evolution of inequalities, their social

  7. Introduction

    DEFF Research Database (Denmark)

    Petersen, Nils Holger; Sandbeck, Lars; Solten, Therese Bering

    2013-01-01

    Introduction to the Special Issue of Literature and Theology publishing articles based on selected papers from the international conference of the International Society for Religion, Literature and Culture (ISRLC) conference held at the Theological Faculty of the University of Copenhagen 19...

  8. Introduction

    DEFF Research Database (Denmark)

    Bandak, Andreas; Janeja, Manpreet Kaur

    2018-01-01

    This introduction foregrounds waiting as a central analytical category to make way for ethnographic attention to uncertain interplays between doubting and hoping. Using a range of focused ethnographies which explore the centrality of waiting in social life, it offers a critical lens...

  9. Introduction

    DEFF Research Database (Denmark)

    Schmidt, Johannes Dragsbæk; Rasiah, Rajah

    2010-01-01

    This is a very interesting book. It is topical and is one of the few volumes that attempts to treat Southeast Asia as an integrated whole. The editors are methodologically ambitious, and they skillfully integrate a very large amount of diverse material in their introduction. I imagine that the bo...... working on the economics and development of Southeast Asia....

  10. Introduction

    International Nuclear Information System (INIS)

    Jacquinot, J.

    1997-01-01

    An introduction to the symposium on nuclear fusion and the CEA researches on magnetic confinement, is presented, with a review of the future energy capacities that fusion could deliver, the technological developments on superconductors, robots, etc. that will assist fusion development, and the european and international cooperation programs on the subject

  11. Introduction

    International Nuclear Information System (INIS)

    Van Walle, E.

    2007-01-01

    The introduction to the annual report 2006 of the Belgian Nuclear Research Centre SCK-CEN highlights the reorganisation of SCK-CEN that became effective in 2006. An overview is given of the principal activities of Institute for Nuclear Materials Science, the Institute for Advanced Nuclear Systems, the Institute for Environment, Health and Safety and the Institute for Communication, Services and Administration

  12. Introduction

    DEFF Research Database (Denmark)

    Seeberg, Peter

    2015-01-01

    states, the Introduction emphasizes the continued relevance of focusing on a repoliticized MENA reality. The Middle East is still on the move away from the established image of unshakeable authoritarianism attributed to the region, which made the upgrading authoritarianism paradigm seem forever relevant......The Introduction briefly presents the ideas behind this collection of articles, namely to analyze popular mobilization and the role of civil society, political parties, and regional organizations in relation to the developments in the Middle East and North Africa (MENA) over the last years......, and to discuss theoretical approaches and paradigms of relevance for the analysis of these new regional dynamics. The MENA region experienced, in connection with and following the Arab uprisings, a hitherto unseen popular mobilization. Despite the recent highly problematic situation in several Middle Eastern...

  13. Introduction

    DEFF Research Database (Denmark)

    Schubart, Rikke

    2017-01-01

    This special issue of the journal Refractory explores identity in the Penny Dreadful.The introduction introduces the show, themes and the six articles. In Season Two of television horror-drama, Penny Dreadful (Showtime/Sky, 2014-16), Ethan Chandler (Josh Hartnett), American sharpshooter and werew......This special issue of the journal Refractory explores identity in the Penny Dreadful.The introduction introduces the show, themes and the six articles. In Season Two of television horror-drama, Penny Dreadful (Showtime/Sky, 2014-16), Ethan Chandler (Josh Hartnett), American sharpshooter...... and werewolf, asks Vanessa Ives (Eva Green), a British heiress with supernatural powers and a troubled past, what happens when the monsters inside of them are released? She says: “We’re most who we are. Unrestrained. Ourselves.” Summing up a central concern of the series, she confirms the view of its creator...

  14. Introduction

    International Nuclear Information System (INIS)

    2003-01-01

    In this chapter the implementation history of the of Inter-disciplinary research complex in the L.N. Gumilev Eurasian State University is illuminated. The responsible institutes participating in the complex designing and it putting into operation are presented. It is noted, that the complex should be a principle facility for solution problems on chemistry, physics and a wide scale advanced technologies. It is suggested, that a nuclear membranes production in the heavy ion accelerator (the key facility of the complex) can be integrating factor of different disciplines and branches and would be a basis for both the nano-technologies and a knowledge intensive business

  15. Introduction

    DEFF Research Database (Denmark)

    Høst, Jeppe Engset

    2015-01-01

    This chapter introduces the notion and theme of market-based fisheries management. The introduction of market mechanisms to distribute and manage fishing quota has internationally occurred since the 1980s but is increasingly on the political agenda. As privatization and transferability are promoted...... internationally, and by big players, it becomes even more crucial to understand its social and environmental implications. This chapter looks at the broader lines in the fisheries research and discusses the diverging views on market-based fisheries management. On one side market mechanisms are promoted...... for efficiency and fleet adaptation, and on the other, quota markets are accused of causing concentration and disturbing social relations....

  16. Introduction

    International Nuclear Information System (INIS)

    Davies, L.M.; Ianko, L.

    1998-01-01

    As a result of the popularity of the Agencies report 'Neutron Irradiation Embrittlement of Reactor Pressure Vessel Steels' of 1975, it was decided that another report on this broad subject would be of use. In the introduction the historic context is established, spanning a bow from the first sustained fission reactor in 1942 to contemporary developments. The subjects 'Irradiation Effects on Mechanical Properties', 'Neutron Fluence', 'Irradiation Effect Trends', 'Empirical Modelling of Irradiation Effects' and 'Mechanical Modelling' are addressed. There are also some remarks about the current state of the art, the migration of irradiation effects and about international programmes

  17. Introduction

    DEFF Research Database (Denmark)

    Peder Pedersen, Claus; Dehs, Jørgen

    2013-01-01

    Introduction to When Architects and Designers Write / Draw / Build / ? This anthology highlights the potentials and challenges for research in architecture and design. The included essays are based on papers given at a symposium held at the Aarhus School of Architecture in 2011 and contain a number...... of topical positions ranging from the activist and academic to practice-based and artistically-based research by international and Danish researchers. The anthology is aimed at architects and designers, as well as others with an interest in the discussion of the concept of research in the fields...

  18. Introduction

    DEFF Research Database (Denmark)

    de Goede, Marieke; Leander, Anna; Sullivan, Gavin

    2016-01-01

    This articles introduces the special issue on ‘The Politics of the List.’ We observe that lists proliferate as a technique of governance across multiple domains, including health, security, and commerce. We argue that it is important to take seriously the form and technique of the list itself...... and engage the knowledge practices, governance effects and ways of ordering the world that the list format enables. In other words, the special issue seeks to ‘remain in the register of the list,’ to unpack its technological arrangements and juridical power. This introduction sets out the key themes...

  19. Introduction

    International Nuclear Information System (INIS)

    2000-01-01

    In the Introduction a brief review on application of high-current electron beams (HEB) and powerful pulse ion beams (PPB) is given. It is noted that at present the following principal trends on HEB and PPB application in technologies are formed: production of super-dense plasma for controlled thermonuclear synthesis; implantation and annealing of semiconductors; modification of metals and alloys properties: strength, tribo-technical and anticorrosion ones; synthesis of new composite materials, including metastable phases and compounds; manufacture of thin films and coverings with preset structure and properties by means of ablation plasma deposition; cleaning, polishing and glancing of surfaces; synthesis of ultra-disperse and nano-sized powders; destruction and cutting of solid materials

  20. Introduction

    Science.gov (United States)

    Kirby, Evan N.

    2018-06-01

    Dwarf galaxies are excellent laboratories of chemical evolution. Many dwarf galaxies have simple star formation histories with very low average star formation rates. These conditions simplify models of chemical evolution and facilitate the identification of sites of nucleosynthesis. Dwarf galaxies also host extremely metal-poor stars, which sample the ejecta of the first generations of supernovae in the universe. This meeting-in-a-meeting, "Stellar Abundances in Dwarf Galasxies," will recognize the importance of dwarf galaxies in learning about the creation and evolution of the elements. Topics include: * the most metal-poor stars * the connection between dwarf galaxies and the Milky Way halo * dwarf galaxies as the paragons of r-process nucleosynthesis * modern techniques in stellar abundance measurements * recent advances in chemical evolution modelingI will give a very brief introduction to set the stage for the meeting.

  1. Performance evaluation and mass transfer study of CO2 absorption in flat sheet membrane contactor using novel porous polysulfone membrane

    International Nuclear Information System (INIS)

    Nabian, Nima; Ghoreyshi, Ali Asghar; Rahimpour, Ahmad; Shakeri, Mohsen

    2015-01-01

    The performance of gas-liquid membrane contactor for CO 2 capture was investigated using a novel polysulfone (PSF) flat membrane prepared via non-solvent phase inversion method. Polyvinyl pyrrolidone (PVP) was used as an additive in the dope solution of PSF membranes. Morphological studies by scanning electron microscopy (SEM) analysis revealed that PSF membrane with PVP has a finger-like structure, but the PSF membrane without PVP has a sponge-like structure. Also, characterization results through atomic force microscopy (AFM) and contact angle measurement demonstrated that the porosity, surface roughness and hydrophobicity of the PSF membrane increased with addition of PVP to the dope solution. Mass transfer resistance analysis, based on CO 2 absorption flux, displayed that addition of PVP to the dope solution of PSF membrane decreased membrane mass transfer resistance, and significantly improved CO 2 absorption flux up to 2.7 and 1.8 times of absorption fluxes of PSF membrane without PVP and commercial PVDF, respectively.

  2. Introduction

    International Nuclear Information System (INIS)

    2002-01-01

    In the Introduction a common data about the monograph are presented. It is noted that results of α-particles elastic and inelastic scattering angular distribution with energies 40.0 and 50.1 MeV on 90,94 Zr carried out on the Kazakhstan isochronous cyclotron U-150M. A new data on total reaction cross sections at α-particles energies 96(1) MeV and 3 He ions 95(1) MeV on 90 Zr isotope, obtained on the Kiev isochronous cyclotron U-240 are given. Within framework of unified approach the experimental data analysis for α-particles quasi-elastic scattering with energies 35.4, 40.0 and 50.1, 65.0 MeV on odd zirconium isotopes as well as their reaction total cross sections is carried out. With use of α-particles scattering at low and middle energies the excited states transitions isospin character for odd tin isotopes is studied in detail with application of up-to date analysis methods. The monograph consists of introduction, four chapters and Conclussion. The chapters are as follows: (1) Experimental measurement methods of differential and total reaction cross sections with complicated particles at low and middle energies; (2) Macroscopic and semi-microscopic optical-potential approaches; (3) Peculiarities of experimental angular distribution of alpha particles at energies up to 12.5 MeV/nucleon, total reaction cross sections and results their optical potential analysis; (4) Structure characteristics of odd-odd nuclei and their comparative analysis

  3. Introduction

    International Nuclear Information System (INIS)

    Toropila, M.

    2006-01-01

    In this introduction to The Third Radiobiological Conference author give a short retrospective review of reactor accidents (26 th April 1986, Chernobyl NPP, 1979 in Three Mile Island). In former Czechoslovakia an attention has been paid to the questions of the effects of radiation on organism from the 1950's. After discharge of Commonwealth the Radiobiological Association. that facilitated interchange of the results of research work among various national and foreign institutions. was also abolished. After establishment of the autonomous Slovak Republic the University of Veterinary Medicine (UVM) in Kosice in collaboration with Pavol Jozef Safarik University in Kosice linked to tradition of radiobiology and organized the the First Radiobiological Conference in Slovakia. At this conference 37 lectures of home and 9 of Czech authors were presented. At the end of conference the agreement was made to held this conference every second year. The 2 nd Radiobiological Conference was held in 2004 at the occasion of the 55 st anniversary of the UVM establishment in Kosice. The 3 rd Conference held on 25 tb May 2006 in UVM in Kosice was inscribed to the 20 th anniversary of Chernobyl disaster. Selected articles dealing with this problem create contents of Supplement inscribed to the 50 th anniversary of the scientific journal Folia Veterinaria

  4. Mass transfer, fluid flow and membrane properties in flat and corrugated plate hyperfiltration modules

    NARCIS (Netherlands)

    Racz, I.G.; Groot Wassink, J.; Klaassen, R.

    1986-01-01

    Concentration polarisation, decreasing the efficiency in membrane separation processes, can be reduced by increasing mass transfer between membrane surface and bulk of the feed stream. Analogous to techniques used in plate heat exchangers efforts have been made to enhance mass transfer in a plate

  5. Determination of SB2 masses and age: introduction of the mass ratio in the Bayesian analysis

    Science.gov (United States)

    Giarrusso, M.; Leone, F.; Tognelli, E.; Degl'Innocenti, S.; Prada Moroni, P. G.

    2018-04-01

    Stellar age assignment still represents a difficult task in Astrophysics. This unobservable fundamental parameter can be estimated only through indirect methods, as well as generally the mass. Bayesian analysis is a statistical approach largely used to derive stellar properties by taking into account the available information about the quantities we are looking for. In this paper we propose to apply the method to the double-lined spectroscopic binaries (SB2), for which the only available information about masses is the observed mass ratio of the two components. We validated the method on a synthetic sample of Pre-Main Sequence (PMS) SB2 systems showing the capability of the technique to recover the simulated age and masses. Then, we applied our procedure to the PMS eclipsing binaries Parenago 1802 and RX J0529.4+0041 A, whose masses of both components are known, by treating them as SB2 systems. The estimated masses are in agreement with those dynamically measured. We conclude that the method, if based on high resolution and high signal-to-noise spectroscopy, represents a robust way to infer the masses of the very numerous SB2 systems together with their age, allowing to date the hosting astrophysical environments.

  6. Determination of SB2 masses and age: introduction of the mass ratio in the Bayesian analysis

    Science.gov (United States)

    Giarrusso, M.; Leone, F.; Tognelli, E.; Degl'Innocenti, S.; Prada Moroni, P. G.

    2018-07-01

    Stellar age assignment still represents a difficult task in Astrophysics. This unobservable fundamental parameter can be estimated only through indirect methods, as well as generally the mass. Bayesian analysis is a statistical approach largely used to derive stellar properties by taking into account the available information about the quantities we are looking for. In this paper, we propose to apply the method to the double-lined spectroscopic binaries (SB2), for which the only available information about masses is the observed mass ratio of the two components. We validated the method on a synthetic sample of pre-main-sequence (PMS) SB2 systems showing the capability of the technique to recover the simulated age and masses. Then, we applied our procedure to the PMS eclipsing binaries Parenago 1802 and RX J0529.4+0041 A, whose masses of both components are known, by treating them as SB2 systems. The estimated masses are in agreement with those dynamically measured. We conclude that the method, if based on high resolution and high signal-to-noise spectroscopy, represents a robust way to infer the masses of the very numerous SB2 systems together with their age, allowing to date the hosting astrophysical environments.

  7. Introduction

    Directory of Open Access Journals (Sweden)

    Jonathan Carson

    2011-08-01

    Full Text Available

    Abstract: Written as Carson & Miller, collaborative artists who explore narrative and the places where narrative intersects with material culture and everyday experience, this introduction presents the stakes of the larger project that entails the exhibition The Story of Things (2009, the conference The Story of Things: reading narrative in the visual (2010 and the double issue of Image (& Narrative. It mainly focuses on the interdisciplinary approaches to the relationship between object and storytelling.

     

    Résumé: Portant la double signature de Carson & Miller, un duo d'artistes avec un intérêt particulier pour la narration et les rapports entre les interaction entre culture ordinaire et  manières de raconter, cette introduction présente les enjeux du projet plus large qui regroupe une exposition

  8. Introduction

    International Nuclear Information System (INIS)

    Zapata, F.; Garcia-Agudo, E.; Ritchie, J.C.; Appleby, P.G.

    2002-01-01

    Soil erosion and associated sedimentation are natural processes caused by water, wind and ice. Several of man's activities such as deforestation, overgrazing, changes in land use, and non-sustainable farming practices tend to accelerate soil erosion. Soil erosion and sedimentation cause not only on-site degradation of a non-renewable natural resource, but also off-site problems such as downstream sediment deposition in fields, floodplains and water streams. These problems and concern over the degradation of the landscape by erosion, and their impacts on soil fertility and crop productivity in agricultural land, water pollution, and sedimentation in lakes, reservoirs, and floodplains are well documented. Global estimates of economic damage from soil erosion and sedimentation have also been made. Recent focus on sustainability issues has resulted in increased attention on soil-degradation problems, in particular soil erosion and sedimentation. In view of increasing water scarcity and limited land resources to feed an ever-growing world population, there is an urgent need to obtain reliable quantitative data on the extent and rates of soil erosion worldwide to provide a more comprehensive assessment of the problem and to underpin the selection of effective soil-conservation technologies and sedimentation remediation strategies, including assessment of their economic and environmental impacts. This chapter describes the use of fallout 137 Cs as a tracer for measuring soil erosion and sedimentation, and the potential use of other radionuclides such as 210 Pb, and 7 Be for these studies. It provides an overview of the 137 Cs technique describing key assumptions and requirements, and advantages and limitations of the technique. Also, applications, recent developments, and future trends of the technique are covered. The chapter is completed with an introduction to the handbook and a list of selected references

  9. Introduction

    Directory of Open Access Journals (Sweden)

    Anuparna Mukherjee

    2017-04-01

    Full Text Available The city as a mosaic of anarchic diversity and messy contradictions has always been a rich source of inspiration for practitioners of creative arts. Writers, painters, planners, photographers, performers have deemed the city as the loci of their desire, conflict, passion and memory to chart the minutes of quotidian life in various intricate forms and configurations. “The city came into being when a surplus of food allowed a diversity of tasks”, Lehan asserts in his introduction to The City in Literature. “Diversity is a key to urban beginnings and continuities, and diversity is also the snake in the urban garden, challenging systems of order and encouraging disorder and chaos” (8. As an eclectic site of cultural friction and contamination that simultaneously oscillates between polarities of belonging and non-belonging, order and chaos, the city unlocks myriad windows to the chroniclers of urban realities. The cities in their perpetual making and dismantling, bear an impression of what Amit Chaudhuri terms in a recent talk as the “unfinished-ness” in the context of modern cities[1]. The “unfinished” is a slippery term as Chaudhuri explains, while it may suggest the Modernist artists’ proclivity towards dereliction, ruin or fragmentation in metropolitan landscape, it also speaks of the “half-made”[2], the backward, or the liminal spaces within an urban conurbation. However, this “unfinished-ness” or the fact that “cities are not finished products” as Chaudhuri posits, is also indicative of their “radical openness” and their inexhaustible potentials for reinventing themselves.

  10. Introduction

    Directory of Open Access Journals (Sweden)

    Donatella Abbate Badin

    2011-08-01

    Full Text Available The introduction to the monographic section Italy-Ireland: Cultural Inter-Relations, gives a brief account of how this part of the journal tries to fill a gap in transcultural studies by investigating the hitherto relatively underexplored relationship of Ireland with Italy. The editors argue that the topic deserves special attention because throughout the centuries, owing to a shared religion and Ireland’s colonial and postcolonial status, a special relationship was established. Without neglecting the many contributions published on this topic over the past thirty years, the papers collected in this first issue of SIJIS offer an overall view of the relations between Italy and Ireland from the Middle Ages to the present day demonstrating this special relationship. The opening essay, drawing an ample and interdisciplinary panorama of the representations of Ireland in Italy over the centuries, and  the concluding one, introducing new issues and suggestions for further investigations, frame seven papers organized thematically in subsections.  The translation studies section highlights some specific problems presented to the translator because of the Irish nature of the translated texts. Exploration of the links between some major figures and Italy opens up new perspectives even regarding much studied figures such as Joyce while  the time-honoured comparative method of studying influences yields ground-breaking insights as in the study of links between Commedia dell’Arte and Clarke or Mahon and Pasolini. Representations of Italy and  the presence of Italian settings and characters acquire  a specific Irish edge in the writings of Synge, Lady Morgan and Edward Maturin especially when both countries were still in search  of their identities.

  11. Introduction

    International Nuclear Information System (INIS)

    Ainul Hayati Daud; Hazmimi Kasim

    2010-01-01

    Since the Atoms for Peace program in 1950s, peaceful applications of nuclear technology has been at the forefront of the development of many countries. In Malaysia, the development of nuclear technology began in earnest with the setting-up of Malaysian Nuclear Agency (Nuclear Malaysia) in 1972, then known as CRANE. More than thirty years later, today, the technology has gained footing and made impact to the development of the country. Her role in regional and international scenes in nuclear-related matters and nuclear technology was noticed and being given due attention. It is time to take stock of this development and assess its impact upon which further developments can be planned and strategized. That was the genesis of this study. This chapter presents a review of the status and development of nuclear technology globally and in Malaysia to provide a background for the report and the study. This is followed by an introduction to the study: its objectives, scope, methods of research, total population, sampling frame, selection procedures, target groups and data analysis. The chapter concludes with a guide to the organization of this report. The study was conducted with the aim of evaluating the impact and contribution of nuclear technology to socio-economic development of the country. It is also expected to identify issues and challenges faced by users of this technology. Even though the applications of nuclear technology encompass diverse human endeavors, this study focuses only in industrial, medical and agriculture sectors. The applications of nuclear technology in both public agencies and private companies in those sectors are considered. This is the first time such a study is being undertaken in Malaysia, and as a starting point, the three year period spanning 2006-2008 are taken as the time frame for discerning trends of nuclear technology development in the country. This study was also in an indirect sense motivated by similar studies conducted in the USA

  12. Multi-layer membrane model for mass transport in a direct ethanol fuel cell using an alkaline anion exchange membrane

    Science.gov (United States)

    Bahrami, Hafez; Faghri, Amir

    2012-11-01

    A one-dimensional, isothermal, single-phase model is presented to investigate the mass transport in a direct ethanol fuel cell incorporating an alkaline anion exchange membrane. The electrochemistry is analytically solved and the closed-form solution is provided for two limiting cases assuming Tafel expressions for both oxygen reduction and ethanol oxidation. A multi-layer membrane model is proposed to properly account for the diffusive and electroosmotic transport of ethanol through the membrane. The fundamental differences in fuel crossover for positive and negative electroosmotic drag coefficients are discussed. It is found that ethanol crossover is significantly reduced upon using an alkaline anion exchange membrane instead of a proton exchange membrane, especially at current densities higher than 500 A m

  13. Heat-And-Mass Transfer Relationship to Determine Shear Stress in Tubular Membrane Systems

    DEFF Research Database (Denmark)

    Ratkovich, Nicolas Rios; Nopens, Ingmar

    2012-01-01

    The main drawback of Membrane Bioreactors (MBRs) is the fouling of the membrane. One way to reduce this fouling is through controlling the hydrodynamics of the two-phase slug flow near the membrane surface. It has been proven in literature that the slug flow pattern has a higher scouring effect...... to remove particulates due to the high shear rates and high mass transfer between the membrane surface and the bulk region. However, to calculate the mass transfer coefficient in an efficient and accurate way is not straightforward. Indeed, for accurate determination, numerous complex experimental...

  14. Introduction

    Science.gov (United States)

    Cohen, E. G. D.

    deduced for irreversible processes (C. Jarzynski). The survey of non-equilibrium steady states in statistical mechanics of classical and quantum systems employs heat bath models and the random matrix theory input. The quantum heat bath analysis and derivation of fluctuation-dissipation theorems is performed by means of the influence functional technique adopted to solve quantum master equations (D. Kusnezov). Chapter II deals with an issue of relaxation and its dynamical theory in both classical and quantum contexts. Pollicott-Ruelle resonance background for the exponential decay scenario is discussed for irreversible processes of diffusion in the Lorentz gas and multibaker models (P. Gaspard). The Pollicott-Ruelle theory reappears as a major inspiration in the survey of the behaviour of ensembles of chaotic systems, with a focus on model systems for which no rigorous results concerning the exponential decay of correlations in time is available (S. Fishman). The observation, that non-equilibrium transport processes in simple classical chaotic systems can be described in terms of fractal structures developing in the system phase space, links their formation and properties with the entropy production in the course of diffusion processes displaying a low dimensional deterministic (chaotic) origin (J. R. Dorfman). Chapter III offers an introduction to the theory of dynamical semigroups. Asymptotic properties of Markov operators and Markov semigroups acting in the set of probability densities (statistical ensemble notion is implicit) are analyzed. Ergodicity, mixing, strong (complete) mixing and sweeping are discussed in the familiar setting of "noise, chaos and fractals" (R. Rudnicki). The next step comprises a passage to quantum dynamical semigroups and completely positive dynamical maps, with an ultimate goal to introduce a consistent framework for the analysis of irreversible phenomena in open quantum systems, where dissipation and decoherence are crucial concepts (R

  15. Introduction

    International Nuclear Information System (INIS)

    Jastrzebski, J.

    2006-01-01

    The Heavy Ion Laboratory of the Warsaw University is the 'User type' facility, providing heavy ion beams to a number of Polish and foreign research groups and to limited extent for its own research programme. In 2005 the Warsaw cyclotron operated for close to 3000 hours of beam on target. 20 experiments, all recommended by the Program Advisory Committee, were performed by more than one hundred facility users. Their scientific achievements are presented in this Report. Here I would like to mention some highlights of the scientific projects with heavy-ion beams delivered by HIL cyclotron. Search for chirality in medium mass nuclei using OSIRIS-II set-up resulted in vivid discussion among nuclear spectroscopists, both theorists and experimentalists. Studies of the quasi-elastic barrier distributions revealed interesting phenomena, not yet fully explainable. Giant Dipole Resonance project with JANOSIK system yielded many new results. Coulomb Excitation investigation of shape coexistence in nuclei was progressing, providing data complementary to those from radioactive beams from CERN and GANIL. Also interesting results concerning optical-model potential in light nuclei interactions were obtained within Warsaw-Krakow-Kiev collaboration. Besides pure nuclear physics the cyclotron delivered beams for projects in solid-state physics, most notably connected to detector development as well as for biological studies. HIL remained an interdisciplinary user facility, keeping high profile of its scientific output, as can be judged from the list of publications contained in Part D of this Report. At the end of 2005 our experimental equipment started to be substantially enlarged. Thanks to the collaboration with the CNRS centre IRES in Strasbourg their excellent charged particle multidetector set-up ICARE was installed on the 'last-free' beam line of the Warsaw Cyclotron. After the well organized transportation and mechanical mounting by an experts team from IRES in collaboration

  16. Modeling the improvement of ultrafiltration membrane mass transfer when using biofiltration pretreatment in surface water applications.

    Science.gov (United States)

    Netcher, Andrea C; Duranceau, Steven J

    2016-03-01

    In surface water treatment, ultrafiltration (UF) membranes are widely used because of their ability to supply safe drinking water. Although UF membranes produce high-quality water, their efficiency is limited by fouling. Improving UF filtrate productivity is economically desirable and has been attempted by incorporating sustainable biofiltration processes as pretreatment to UF with varying success. The availability of models that can be applied to describe the effectiveness of biofiltration on membrane mass transfer are lacking. In this work, UF water productivity was empirically modeled as a function of biofilter feed water quality using either a quadratic or Gaussian relationship. UF membrane mass transfer variability was found to be governed by the dimensionless mass ratio between the alkalinity (ALK) and dissolved organic carbon (DOC). UF membrane productivity was optimized when the biofilter feed water ALK to DOC ratio fell between 10 and 14. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Analysis of mass transfer characteristics in a tubular membrane using CFD modeling.

    Science.gov (United States)

    Yang, Jixiang; Vedantam, Sreepriya; Spanjers, Henri; Nopens, Ingmar; van Lier, Jules B

    2012-10-01

    In contrast to the large amount of research into aerobic membrane bioreactors, little work has been reported on anaerobic membrane bioreactors (AMBRs). As to the application of membrane bioreactors, membrane fouling is a key issue. Membrane fouling generally occurs more seriously in AMBRs than in aerobic membrane bioreactors. However, membrane fouling could be managed through the application of suitable shear stress that can be introduced by the application of a two-phase flow. When the two-phase flow is applied in AMBRs, little is known about the mass transfer characteristics, which is of particular importance, in tubular membranes of AMBRs. In our present work, we have employed fluid dynamic modeling to analyze the mass transfer characteristics in the tubular membrane of a side stream AMBR in which, gas-lift two-phase flow was applied. The modeling indicated that the mass transfer capacity at the membrane surface at the noses of gas bubbles was higher than the mass transfer capacity at the tails of the bubbles, which is in contrast to the results when water instead of sludge is applied. At the given mass transfer rate, the filterability of the sludge was found to have a strong influence on the transmembrane pressure at a steady flux. In addition, the model also showed that the shear stress in the internal space of the tubular membrane was mainly around 20 Pa but could be as high as about 40 Pa due to gas bubble movements. Nonetheless, at these shear stresses a stable particle size distribution was found for sludge particles. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Liquid sample introduction in inductively coupled plasma atomic emission and mass spectrometry — Critical review

    Energy Technology Data Exchange (ETDEWEB)

    Bings, N.H., E-mail: bings@uni-mainz.de; Orlandini von Niessen, J.O.; Schaper, J.N.

    2014-10-01

    Inductively coupled plasma optical emission spectroscopy (ICP-OES) and mass spectrometry (ICP-MS) can be considered as the most important tools in inorganic analytical chemistry. Huge progress has been made since the first analytical applications of the ICP. More stable RF generators, improved spectrometers and detection systems were designed along with the achievements gained from advanced microelectronics, leading to overall greatly improved analytical performance of such instruments. In contrast, for the vast majority of cases liquid sample introduction is still based on the pneumatic principle as described in the late 19th century. High flow pneumatic nebulizers typically demand the use of spray chambers as “aerosol filters” in order to match the prerequisites of an ICP. By this, only a small fraction of the nebulized sample actually contributes to the measured signal. Hence, the development of micronebulizers was brought forward. Those systems produce fine aerosols at low sample uptake rates, but they are even more prone for blocking or clogging than conventional systems in the case of solutions containing a significant amount of total dissolved solids (TDS). Despite the high number of publications devoted to liquid sample introduction, it is still considered the Achilles' heel of atomic spectrometry and it is well accepted, that the technology used for liquid sample introduction is still far from ideal, even when applying state-of-the-art systems. Therefore, this review is devoted to offer an update on developments in the field liquid sample introduction that had been reported until the year 2013. The most recent and noteworthy contributions to this field are discussed, trends are highlighted and future directions are outlined. The first part of this review provides a brief overview on theoretical considerations regarding conventional pneumatic nebulization, the fundamentals on aerosol generation and discusses characteristics of aerosols ideally

  19. Liquid sample introduction in inductively coupled plasma atomic emission and mass spectrometry — Critical review

    International Nuclear Information System (INIS)

    Bings, N.H.; Orlandini von Niessen, J.O.; Schaper, J.N.

    2014-01-01

    Inductively coupled plasma optical emission spectroscopy (ICP-OES) and mass spectrometry (ICP-MS) can be considered as the most important tools in inorganic analytical chemistry. Huge progress has been made since the first analytical applications of the ICP. More stable RF generators, improved spectrometers and detection systems were designed along with the achievements gained from advanced microelectronics, leading to overall greatly improved analytical performance of such instruments. In contrast, for the vast majority of cases liquid sample introduction is still based on the pneumatic principle as described in the late 19th century. High flow pneumatic nebulizers typically demand the use of spray chambers as “aerosol filters” in order to match the prerequisites of an ICP. By this, only a small fraction of the nebulized sample actually contributes to the measured signal. Hence, the development of micronebulizers was brought forward. Those systems produce fine aerosols at low sample uptake rates, but they are even more prone for blocking or clogging than conventional systems in the case of solutions containing a significant amount of total dissolved solids (TDS). Despite the high number of publications devoted to liquid sample introduction, it is still considered the Achilles' heel of atomic spectrometry and it is well accepted, that the technology used for liquid sample introduction is still far from ideal, even when applying state-of-the-art systems. Therefore, this review is devoted to offer an update on developments in the field liquid sample introduction that had been reported until the year 2013. The most recent and noteworthy contributions to this field are discussed, trends are highlighted and future directions are outlined. The first part of this review provides a brief overview on theoretical considerations regarding conventional pneumatic nebulization, the fundamentals on aerosol generation and discusses characteristics of aerosols ideally

  20. Simultaneous electrothermal vaporization and nebulizer sample introduction system for inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Arnquist, Isaac J.; Kreschollek, Thomas E.; Holcombe, James A.

    2011-01-01

    The novel analytical application of the combination of an inline electrothermal vaporization (ETV) and nebulization source for inductively coupled plasma mass spectrometry (ICP-MS) has been studied. Wet plasma conditions are sustained during ETV introduction by 200 mL/min gas flow through the nebulizer, which is merged with the ETV transport line at the torch. The use of a wet plasma with ETV introduction avoided the need to change power settings and torch positions that normally accompany a change from wet to dry plasma operating conditions. This inline-ETV source is shown to have good detection limits for a variety of elements in both HNO 3 and HCl matrices. Using the inline-ETV source, improved limits of detection (LOD) were obtained for elements typically suppressed by polyatomic interferences using a nebulizer. Specifically, improved LODs for 51 V and 53 Cr suffering from Cl interferences ( 51 ClO + and 53 ClO + respectively) in a 1% HCl matrix were obtained using the inline-ETV source. LODs were improved by factors of 65 and 22 for 51 V and 53 Cr, respectively, using the inline-ETV source compared to a conventional concentric glass nebulizer. For elements without polyatomic interferences, LODs from the inline-ETV were comparable to conventional dry plasma ETV-ICP time-of-flight mass spectrometry results. Lastly, the inline-ETV source offers a simple means of changing from nebulizer introduction to inline-ETV introduction without extinguishing the plasma. This permits, for example, the use of the time-resolved ETV-ICP-MS signals to distinguish between an analyte ion and polyatomic isobar.

  1. Sodium laurate, a novel protease- and mass spectrometry-compatible detergent for mass spectrometry-based membrane proteomics.

    Directory of Open Access Journals (Sweden)

    Yong Lin

    Full Text Available The hydrophobic nature of most membrane proteins severely complicates their extraction, proteolysis and identification. Although detergents can be used to enhance the solubility of the membrane proteins, it is often difficult for a detergent not only to have a strong ability to extract membrane proteins, but also to be compatible with the subsequent proteolysis and mass spectrometric analysis. In this study, we made evaluation on a novel application of sodium laurate (SL to the shotgun analysis of membrane proteomes. SL was found not only to lyse the membranes and solubilize membrane proteins as efficiently as SDS, but also to be well compatible with trypsin and chymotrypsin. Furthermore, SL could be efficiently removed by phase transfer method from samples after acidification, thus ensuring not to interfere with the subsequent CapLC-MS/MS analysis of the proteolytic peptides of proteins. When SL was applied to assist the digestion and identification of a standard protein mixture containing bacteriorhodoposin and the proteins in rat liver plasma membrane-enriched fractions, it was found that, compared with other two representative enzyme- and MS-compatible detergents RapiGest SF (RGS and sodium deoxycholate (SDC, SL exhibited obvious superiority in the identification of membrane proteins particularly those with high hydrophobicity and/or multiple transmembrane domains.

  2. Amplified CPEs enhancement of chorioamnion membrane mass transport by encapsulation in nano-sized PLGA particles.

    Science.gov (United States)

    Azagury, Aharon; Amar-Lewis, Eliz; Appel, Reut; Hallak, Mordechai; Kost, Joseph

    2017-08-01

    Chemical penetration enhancers (CPEs) have long been used for mass transport enhancement across membranes. Many CPEs are used in a solution or gel and could be a solvent. The use of CPEs is mainly limited due to their toxicity/irritation levels. This study presents the evaluation of encapsulated CPEs in nano-sized polymeric particles on the chorioamnion (CA) membrane mass transport. CPEs' mass encapsulated in nanoparticles was decreased by 10,000-fold. Interestingly, this approach resulted in a 6-fold increase in mass transport across the CA. This approach may also be used with other CPEs' base applications necessitating lower CPE concentration. Applying Ultrasound (US) has shown to increase the release rate of and also the mass transport across the CA membrane. It is proposed that encapsulated CPEs penetrate into the CA membrane thus prolonging their exposure, possibly extending their penetration into the CA membrane, while insonation also deepens their penetration into the CA membrane. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Ozone mass transfer behaviors on physical and chemical absorption for hollow fiber membrane contactors.

    Science.gov (United States)

    Zhang, Yong; Li, Kuiling; Wang, Jun; Hou, Deyin; Liu, Huijuan

    2017-09-01

    To understand the mass transfer behaviors in hollow fiber membrane contactors, ozone fluxes affected by various conditions and membranes were investigated. For physical absorption, mass transfer rate increased with liquid velocity and the ozone concentration in the gas. Gas flow rate was little affected when the velocity was larger than the critical value, which was 6.1 × 10 -3 m/s in this study. For chemical absorption, the flux was determined by the reaction rate between ozone and the absorbent. Therefore, concentration, species, and pH affected the mass transfer process markedly. For different absorbents, the order of mass transfer rate was the same as the reaction rate constant, which was phenol, sodium nitrite, hydrogen peroxide, and oxalate. Five hydrophobic membranes with various properties were employed and the mass transfer behavior can be described by the Graetz-Lévèque equation for the physical absorption process. The results showed the process was controlled by liquid film and the gas phase conditions, and membrane properties did not affect the ozone flux. For the chemical absorption, gas film, membrane and liquid film affected the mass transfer together, and none of them were negligible.

  4. The mass balance of a Proton Exchange Membrane Fuel Cell (PEMFC)

    International Nuclear Information System (INIS)

    Miloud, S.; Kamaruzzaman Sopian; Wan Ramli Wan Daud

    2006-01-01

    A Proton Exchange Membrane Fuel Cell (PEMFC), operating at low temperature uses a simple chemical process to combine hydrogen and oxygen into water, producing electric current and heat during the electrochemical reaction. This work concern on the theoretical consideration of the mass balance has been evaluated to predict the mass flow rate of the both gases (hydrogen/oxygen), the water mass balance, and the heat transfer in order to design a single cell PEMFC stack with a better flow field distributor on the performance of Polymer Electrolyte membrane fuel cells

  5. Research on mass transfer and actual performance of the membrane regeneration air-conditioning system

    International Nuclear Information System (INIS)

    Li, Xiu-Wei; Zhang, Xiao-Song; Chen, Qing

    2015-01-01

    Highlights: • Experimental research has been made on the membrane air-conditioning system. • We develop mass transfer models for the membrane regeneration process. • The paper exposes the actual performance of the system. • Increase of membrane pairs improves the performance. - Abstract: Absorption air-conditioning system has great advantages in energy conservation and environmental protection. To improve the performance of the traditional system, the membrane regeneration absorption system was proposed. Its COP could approach 6 by regenerating absorbent solution with the ion exchange membranes. However, the theoretical conclusion has not been supported by the experiment. This paper presents the experimental research of the membrane regeneration process. It has investigated the mass transfer process, energy efficiency and actual performance under different working conditions. Based on that, a mass transfer model has been developed and the influences of some key parameters have been exposed. It found the regeneration performance is mainly influenced by the current intensity. The calculation results with the model agree well the experimental data. The actual efficiency was lower than 50%, caused by energy loss in heat and electrochemical reactions. The actual COP is between 1 and 3, lower current intensity and more membrane pairs could improve it.

  6. Reverse membrane bioreactor: Introduction to a new technology for biofuel production.

    Science.gov (United States)

    Mahboubi, Amir; Ylitervo, Päivi; Doyen, Wim; De Wever, Heleen; Taherzadeh, Mohammad J

    2016-01-01

    The novel concept of reverse membrane bioreactors (rMBR) introduced in this review is a new membrane-assisted cell retention technique benefiting from the advantageous properties of both conventional MBRs and cell encapsulation techniques to tackle issues in bioconversion and fermentation of complex feeds. The rMBR applies high local cell density and membrane separation of cell/feed to the conventional immersed membrane bioreactor (iMBR) set up. Moreover, this new membrane configuration functions on basis of concentration-driven diffusion rather than pressure-driven convection previously used in conventional MBRs. These new features bring along the exceptional ability of rMBRs in aiding complex bioconversion and fermentation feeds containing high concentrations of inhibitory compounds, a variety of sugar sources and high suspended solid content. In the current review, the similarities and differences between the rMBR and conventional MBRs and cell encapsulation regarding advantages, disadvantages, principles and applications for biofuel production are presented and compared. Moreover, the potential of rMBRs in bioconversion of specific complex substrates of interest such as lignocellulosic hydrolysate is thoroughly studied. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Early Detection of Biofouling on Water Purification Membranes by Ambient Ionization Mass Spectrometry Imaging.

    Science.gov (United States)

    Jakka Ravindran, Swathy; Kumar, Ramesh; Srimany, Amitava; Philip, Ligy; Pradeep, Thalappil

    2018-01-02

    By direct analysis of water purification membranes using ambient ionization mass spectrometry, an attempt has been made to understand the molecular signatures of bacterial fouling. Membrane based purification methods are used extensively in water treatment, and a major challenge for them is biofouling. The buildup of microbes and their extracellular polymeric matrix clog the purification membranes and reduce their efficiency. To understand the early stages of bacterial fouling on water purification membranes, we have used desorption electrospray ionization mass spectrometry (DESI MS), where ion formation occurs in ambient conditions and the ionization event is surface sensitive. Biosurfactants at the air-water interface generated by microorganisms as a result of quorum sensing, influence the water-membrane interface and are important for the bacterial attachment. We show that these biosurfactants produced by bacteria can be indicator molecular species signifying initiation of biofilms on membrane surfaces, demonstrated by specific DESI MS signatures. In Pseudomonas aeruginosa, one of the best studied models for biofilm formation, this process is mediated by rhamnolipids forewarning bacterial fouling. Species dependent variation of such molecules can be used for the precise identification of the microorganisms, as revealed by studies on P. aeroginosa (ATCC 25619). The production of biosurfactants is tightly regulated at the transcriptional level by the quorum-sensing (QS) response. Thus, secretion of these extracellular molecules across the membrane surface allows rapid screening of the biofilm community. We show that, the ambient ionization mass spectrometry can detect certain toxic heavy metals present in water, using surfactant-metal complexes as analytes. We believe that such studies conducted on membranes in various input water streams will help design suitable membrane processes specific to the input streams.

  8. New high temperature plasmas and sample introduction systems for analytical atomic emission and mass spectrometry

    International Nuclear Information System (INIS)

    Montaser, A.

    1993-01-01

    In this research, new high-temperature plasmas and new sample introduction systems are explored for rapid elemental and isotopic analysis of gases, solutions, and solids using mass spectrometry and atomic emission spectrometry. During the period January 1993--December 1993, emphasis was placed on (a) analytical investigations of atmospheric-pressure helium inductively coupled plasma (He ICP) that are suitable for atomization, excitation, and ionization of elements possessing high excitation and ionization energies; (b) simulation and computer modeling of plasma sources to predict their structure and fundamental and analytical properties without incurring the enormous cost of experimental studies; (c) spectrosopic imaging and diagnostic studies of high-temperature plasmas; (d) fundamental studies of He ICP discharges and argon-nitrogen plasma by high-resolution Fourier transform spectrometry; and (e) fundamental and analytical investigation of new, low-cost devices as sample introduction systems for atomic spectrometry and examination of new diagnostic techniques for probing aerosols. Only the most important achievements are included in this report to illustrate progress and obstacles. Detailed descriptions of the authors' investigations are outlined in the reprints and preprints that accompany this report. The technical progress expected next year is briefly described at the end of this report

  9. Mass spectrometer introduction line: application to the analysis of impurities in uranium hexafluoride

    International Nuclear Information System (INIS)

    Besson, M.

    1967-01-01

    The continuous mass-spectrometric analysis of impurities in UF 6 is possible industrially if certain conditions imposed by the nature of the gas are respected. The gas introduction line arriving at the spectrometer's source makes it possible to fix the flow-rate, to control the inlet pressure and to selectively destroy the gas containing the impurities. The operational conditions for the line are defined and a description is given of the theoretical and experimental study of the various elements of which it is composed, i.e. the leak valve, the flow-meter, the chemical trap and the servo-mechanism making it possible to regulate and control the gas flow. The dynamic characteristics of the line's various components and the performance of the equipment in the case of the analyses considered are given. (author) [fr

  10. An introduction to drug testing: the expanding role of mass spectrometry.

    Science.gov (United States)

    Hammett-Stabler, Catherine; Cotten, Steven W

    2012-01-01

    Measurement of drugs and their metabolites in biological fluids is the foundation of both therapeutic drug monitoring (TDM) and toxicology. Though different in their application, each discipline depends upon accurate identification and quantification if the measurements are to be useful. Thousands of methods are described for drug analysis but until recently most have relied upon analytical tools, such as spectrophotometry and immunoassay, that suffer from lack of specificity and sensitivity. The introduction of methods based on mass spectrometry (MS), coupled to gas or liquid chromatography, has revolutionized these areas. The methods are proving to be robust, versatile, and economical. This chapter introduces the reader to the application of MS to TDM and toxicology, the steps that should be considered during implementation, and the processes that should be implemented to assure continued quality.

  11. Species Uptake and Mass Transport in Membranes for Vanadium Redox Flow Batteries

    International Nuclear Information System (INIS)

    Elgammal, Ramez A.; Tang, Zhijiang; Sun, Che-Nan; Lawton, Jamie; Zawodzinski, Thomas A.

    2017-01-01

    In this contribution, we provide a synthesis of results to date describing uptake and mass transport of water, vanadium species and protons in Nafion membranes for use as separators in VRFBs. Resistance issues as well as species cross-over are important contributors to performance loss in VRFBs. After a brief discussion of our state-of-the-art cell performance, we consider the uptake and transport of various species through a number of membrane materials. We draw together numerous previous studies and augment them with new data to provide a summary of our present state of understanding of the experimental facts regarding membrane behavior.

  12. Theoretical studies on membrane-based gas separation using computational fluid dynamics (CFD) of mass transfer

    International Nuclear Information System (INIS)

    Sohrabi, M.R.; Marjani, A.; Davallo, M.; Moradi, S.; Shirazian, S.

    2011-01-01

    A 2D mass transfer model was developed to study carbon dioxide removal by absorption in membrane contactors. The model predicts the steady state absorbent and carbon dioxide concentrations in the membrane by solving the conservation equations. The continuity equations for three sub domains of the membrane contactor involving the tube; membrane and shell were obtained and solved by finite element method (FEM). The model was based on 'non-wetted mode' in which the gas phase filled the membrane pores. Laminar parabolic velocity profile was used for the liquid flow in the tube side; whereas, the gas flow in the shell side was characterized by Happel's free surface model. Axial and radial diffusion transport inside the shell, through the membrane, and within the tube side of the contactor was considered in the mass transfer model. The predictions of percent CO/sub 2/ removal obtained by modeling were compared with the experimental values obtained from literature. They were the experimental results for CO/sub 2/ removal from CO/sub 2//N/sub 2/ gas mixture with amines aqueous solutions as the liquid solvent using polypropylene membrane contactor. The modeling predictions were in good agreement with the experimental values for different values of gas and liquid flow rates. (author)

  13. Definition of the mitochondrial proteome by measurement of molecular masses of membrane proteins

    Science.gov (United States)

    Carroll, Joe; Fearnley, Ian M.; Walker, John E.

    2006-01-01

    The covalent structure of a protein is incompletely defined by its gene sequence, and mass spectrometric analysis of the intact protein is needed to detect the presence of any posttranslational modifications. Because most membrane proteins are purified in detergents that are incompatible with mass spectrometric ionization techniques, this essential measurement has not been made on many hydrophobic proteins, and so proteomic data are incomplete. We have extracted membrane proteins from bovine mitochondria and detergent-purified NADH:ubiquinone oxidoreductase (complex I) with organic solvents, fractionated the mixtures by hydrophilic interaction chromatography, and measured the molecular masses of the intact membrane proteins, including those of six subunits of complex I that are encoded in mitochondrial DNA. These measurements resolve long-standing uncertainties about the interpretation of the mitochondrial genome, and they contribute significantly to the definition of the covalent composition of complex I. PMID:17060615

  14. Determination of membrane degradation products in the product water of polymer electrolyte membrane fuel cells using liquid chromatography mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zedda, Marco

    2011-05-12

    The predominant long term failure of polymer electrolyte membranes (PEM) is caused by hydroxyl radicals generated during fuel cell operation. These radicals attack the polymer, leading to chain scission, unzipping and consequently to membrane decomposition products. The present work has investigated decomposition products of novel sulfonated aromatic hydrocarbon membranes on the basis of a product water analysis. Degradation products from the investigated membrane type and the possibility to detect these compounds in the product water for diagnostic purposes have not been discovered yet. This thesis demonstrates the potential of solid phase extraction and liquid chromatography tandem mass spectrometry (SPE-LC-MS/MS) for the extraction, separation, characterization, identification and quantification of membrane degradation products in the product water of fuel cells. For this purpose, several polar aromatic hydrocarbons with different functional groups were selected as model compounds for the development of reliable extraction, separation and detection methods. The results of this thesis have shown that mixed mode sorbent materials with both weak anion exchange and reversed phase retention properties are well suited for reproducible extraction of both molecules and ions from the product water. The chromatographic separation of various polar aromatic hydrocarbons was achieved by means of phase optimized liquid chromatography using a solvent gradient and on a C18 stationary phase. Sensitive and selective detection of model compounds could be successfully demonstrated by the analysis of the product water using tandem mass spectrometry. The application of a hybrid mass spectrometer (Q Trap) for the characterization of unknown polar aromatic hydrocarbons has led to the identification and confirmation of 4-hydroxybenzoic acid in the product water. In addition, 4-HBA could be verified as a degradation product resulting from PEM decomposition by hydroxyl radicals using an

  15. A Method for Estimating Mass-Transfer Coefficients in a Biofilter from Membrane Inlet Mass Spectrometer Data

    DEFF Research Database (Denmark)

    Nielsen, Anders Michael; Nielsen, Lars Peter; Feilberg, Anders

    2009-01-01

    A membrane inlet mass spectrometer (MIMS) was used in combination with a developed computer model to study and improve management of a biofilter (BF) treating malodorous ventilation air from a meat rendering facility. The MIMS was used to determine percentage removal efficiencies (REs) of selected...... sulfur gases and to provide toluene retention profiles for the model to determine the air velocity and overall mass-transfer coefficient of toluene. The mass-transfer coefficient of toluene was used as a reference for determining the mass transfer of sulfur gases. By presenting the model to scenarios...... of a filter bed with a consortium of effective sulfur oxidizers, the most likely mechanism for incomplete removal of sulfur compounds from the exhaust air was elucidated. This was found to be insufficient mass transfer and not inadequate bacterial activity as anticipated by the manager of the BF. Thus...

  16. The influence of polymeric membrane gas spargers on hydrodynamics and mass transfer in bubble column bioreactors

    DEFF Research Database (Denmark)

    Tirunehe, Gossay; Norddahl, B.

    2016-01-01

    Gas sparging performances of a flat sheet and tubular polymeric membranes were investigated in 3.1 m bubble column bioreactor operated in a semi batch mode. Air–water and air–CMC (Carboxymethyl cellulose) solutions of 0.5, 0.75 and 1.0 % w/w were used as interacting gas–liquid mediums. CMC....../s. The study indicated that the tubular membrane sparger produced the highest gas holdup and densely populated fine bubbles with narrow size distribution. An increase in liquid viscosity promoted a shift in bubble size distribution to large stable bubbles and smaller specific interfacial area. The tubular...... membrane sparger achieved greater interfacial area and an enhanced overall mass transfer coefficient (KLa) by a factor of 1.2–1.9 compared to the flat sheet membrane....

  17. Selective enantioseparation of levocetirizine via a hollow fiber supported liquid membrane and mass transfer prediction

    International Nuclear Information System (INIS)

    Sunsandee, Niti; Leepipatpiboon, Natchanun; Ramakul, Prakorn

    2013-01-01

    The enantioselective separation of levocetirizine via a hollow fiber supported liquid membrane was examined. O,O'-dibenzoyl-(2R,3R)-tartaric acid ((-)-DBTA) diluted in 1-decanol was used as a chiral selector extractant. The influence of concentrations of feed and stripping phases, and extractant concentration in the membrane phase, was also investigated. A mathematical model focusing on the extraction side of the liquid membrane system was presented to predict the concentration of levocetirizine at different times. The extraction and recovery of levocetirizine from feed phase were 75.00% and 72.00%, respectively. The mass transfer coefficients at aqueous feed boundary layer (k_f) and the organic liquid membrane phase (k_m) were calculated as 2.41x10"2 and 1.89x10"2 cm/s, respectively. The validity of the developed model was evaluated through a comparison with experimental data, and good agreement was obtained

  18. Selective enantioseparation of levocetirizine via a hollow fiber supported liquid membrane and mass transfer prediction

    Energy Technology Data Exchange (ETDEWEB)

    Sunsandee, Niti [Government Pharmaceutical Organization, Bangkok (Thailand); Leepipatpiboon, Natchanun [Chulalongkorn University, Bangkok (Thailand); Ramakul, Prakorn [Silpakorn University, Nakhon Pathom (Thailand)

    2013-06-15

    The enantioselective separation of levocetirizine via a hollow fiber supported liquid membrane was examined. O,O'-dibenzoyl-(2R,3R)-tartaric acid ((-)-DBTA) diluted in 1-decanol was used as a chiral selector extractant. The influence of concentrations of feed and stripping phases, and extractant concentration in the membrane phase, was also investigated. A mathematical model focusing on the extraction side of the liquid membrane system was presented to predict the concentration of levocetirizine at different times. The extraction and recovery of levocetirizine from feed phase were 75.00% and 72.00%, respectively. The mass transfer coefficients at aqueous feed boundary layer (k{sub f}) and the organic liquid membrane phase (k{sub m}) were calculated as 2.41x10{sup 2} and 1.89x10{sup 2} cm/s, respectively. The validity of the developed model was evaluated through a comparison with experimental data, and good agreement was obtained.

  19. Model mass spectrometric study of competitive interactions of antimicrobial bisquaternary ammonium drugs and aspirin with membrane phospholipids

    Directory of Open Access Journals (Sweden)

    Vekey K.

    2013-03-01

    Full Text Available The aim of the study is to reveal molecular mechanisms of possible activity modulation of antimicrobial bis-quaternary ammonium compounds (BQAC and aspirin (ASP through noncovalent competitive complexation under their combined introduction into the model systems with membrane phospholipids. Methods. Binary and triple systems containing either decamethoxinum or ethonium, or thionium and aspirin, as well as dipalmitoyl-phosphatidylcholine (DPPC have been investigated by electrospray ionization mass spectrometry. Results. Basing on the analysis of associates recorded in the mass spectra, the types of nonocovalent complexes formed in the systems studied were determined and the supposed role of the complexation in the BQAC and ASP activity modulation was discussed. The formation of associates of BQAC dications with ASP anion is considered as one of the possible ways of deactivation of ionic forms of the medications. The formation of stable complexes of BQAC with DPPC and ASP with DPPC in binary systems as well as the complexes distribution in triple-components systems BQAC:ASP:DPPC point to the existence of competition between drugs of these two types for the binding to DPPC. Conclusions. The results obtained point to the competitive complexation in the model molecular systems containing the BQAC, aspirin and membrane phospholipids. The observed phenomenon testifies to the possibility of modulating the activity of bisquaternary antimicrobial agents and aspirin under their combined usage, due to the competition between the drugs for binding to the target membrane phospholipid molecules and also due to the formation of stable noncovalent complexes between BQAC and ASP.

  20. Profiling of kidney vascular endothelial cell plasma membrane proteins by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Liu, Zan; Xu, Bo; Nameta, Masaaki; Zhang, Ying; Magdeldin, Sameh; Yoshida, Yutaka; Yamamoto, Keiko; Fujinaka, Hidehiko; Yaoita, Eishin; Tasaki, Masayuki; Nakagawa, Yuki; Saito, Kazuhide; Takahashi, Kota; Yamamoto, Tadashi

    2013-06-01

    Vascular endothelial cells (VECs) play crucial roles in physiological and pathologic conditions in tissues and organs. Most of these roles are related to VEC plasma membrane proteins. In the kidney, VECs are closely associated with structures and functions; however, plasma membrane proteins in kidney VECs remain to be fully elucidated. Rat kidneys were perfused with cationic colloidal silica nanoparticles (CCSN) to label the VEC plasma membrane. The CCSN-labeled plasma membrane fraction was collected by gradient ultracentrifugation. The VEC plasma membrane or whole-kidney lysate proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and digested with trypsin in gels for liquid chromatography-tandem mass spectrometry. Enrichment analysis was then performed. The VEC plasma membrane proteins were purified by the CCSN method with high yield (approximately 20 μg from 1 g of rat kidney). By Mascot search, 582 proteins were identified in the VEC plasma membrane fraction, and 1,205 proteins were identified in the kidney lysate. In addition to 16 VEC marker proteins such as integrin beta-1 and intercellular adhesion molecule-2 (ICAM-2), 8 novel proteins such as Deltex 3-like protein and phosphatidylinositol binding clathrin assembly protein (PICALM) were identified. As expected, many key functions of plasma membranes in general and of endothelial cells in particular (i.e., leukocyte adhesion) were significantly overrepresented in the proteome of CCSN-labeled kidney VEC fraction. The CCSN method is a reliable technique for isolation of VEC plasma membrane from the kidney, and proteomic analysis followed by bioinformatics revealed the characteristics of in vivo VECs in the kidney.

  1. A robust mass spectrometry method for rapid profiling of erythrocyte ghost membrane proteomes.

    Science.gov (United States)

    Fye, Haddy K S; Mrosso, Paul; Bruce, Lesley; Thézénas, Marie-Laëtitia; Davis, Simon; Fischer, Roman; Rwegasira, Gration L; Makani, Julie; Kessler, Benedikt M

    2018-01-01

    Red blood cell (RBC) physiology is directly linked to many human disorders associated with low tissue oxygen levels or anemia including chronic obstructive pulmonary disease, congenital heart disease, sleep apnea and sickle cell anemia. Parasites such as Plasmodium spp. and phylum Apicomplexa directly target RBCs, and surface molecules within the RBC membrane are critical for pathogen interactions. Proteomics of RBC membrane 'ghost' fractions has therefore been of considerable interest, but protocols described to date are either suboptimal or too extensive to be applicable to a larger set of clinical cohorts. Here, we describe an optimised erythrocyte isolation protocol from blood, tested for various storage conditions and explored using different fractionation conditions for isolating ghost RBC membranes. Liquid chromatography mass spectrometry (LC-MS) analysis on a Q-Exactive Orbitrap instrument was used to profile proteins isolated from the comparative conditions. Data analysis was run on the MASCOT and MaxQuant platforms to assess their scope and diversity. The results obtained demonstrate a robust method for membrane enrichment enabling consistent MS based characterisation of > 900 RBC membrane proteins in single LC-MS/MS analyses. Non-detergent based membrane solubilisation methods using the tissue and supernatant fractions of isolated ghost membranes are shown to offer effective haemoglobin removal as well as diverse recovery including erythrocyte membrane proteins of high and low abundance. The methods described in this manuscript propose a medium to high throughput framework for membrane proteome profiling by LC-MS of potential applicability to larger clinical cohorts in a variety of disease contexts.

  2. Sound insulation property of membrane-type acoustic metamaterials carrying different masses at adjacent cells

    Science.gov (United States)

    Zhang, Yuguang; Wen, Jihong; Zhao, Honggang; Yu, Dianlong; Cai, Li; Wen, Xisen

    2013-08-01

    We present the experimental realization and theoretical understanding of membrane-type acoustic metamaterials embedded with different masses at adjacent cells, capable of increasing the transmission loss at low frequency. Owing to the reverse vibration of adjacent cells, Transmission loss (TL) peaks appear, and the magnitudes of the TL peaks exceed the predicted results of the composite wall. Compared with commonly used configuration, i.e., all cells carrying with identical mass, the nonuniformity of attaching masses causes another much low TL peak. Finite element analysis was employed to validate and provide insights into the TL behavior of the structure.

  3. Diffusive transfer to membranes as an effective interface between gel electrophoresis and mass spectrometry

    Science.gov (United States)

    Ogorzalek Loo, Rachel R.; Mitchell, Charles; Stevenson, Tracy I.; Loo, Joseph A.; Andrews, Philip C.

    1997-12-01

    Diffusive transfer was examined as a blotting method to transfer proteins from polyacrylamide gels to membranes for ultraviolet matrix-assisted laser desorption ionization (MALDI) mass spectrometry. The method is well-suited for transfers from isoelectric focusing (IEF) gels. Spectra have been obtained for 11 pmol of 66 kDa albumin loaded onto an IEF gel and subsequently blotted to polyethylene. Similarly, masses of intact carbonic anhydrase and hemoglobin were obtained from 14 and 20 pmol loadings. This methodology is also compatible with blotting high molecular weight proteins, as seen for 6 pmol of the 150 kDa monoclonal antibody anti-[beta]-galactosidase transferred to Goretex. Polypropylene, Teflon, Nafion and polyvinylidene difluoride (PVDF) also produced good spectra following diffusive transfer. Only analysis from PVDF required that the membrane be kept wet prior to application of matrix. Considerations in mass accuracy for analysis from large-area membranes with continuous extraction and delayed extraction were explored, as were remedies for surface charging. Vapor phase CNBr cleavage was applied to membrane-bound samples for peptide mapping.

  4. Direct solution introduction using conventional nebulizers with a short torch for plasma mass spectrometry

    International Nuclear Information System (INIS)

    Westphal, Craig S.; Montaser, Akbar

    2006-01-01

    -high efficiency nebulizer-short torch system is 3.1% and 3.7% based on peak areas and heights, respectively, at a solution uptake rate of 85 μL/min. Good agreement is obtained between certified and measured concentrations for several elements across the mass range (e.g., Al, V, Mn, As, Cd, Pb, U). The proposed system is novel because it potentially offers a lower-cost and a more universal arrangement for improved direct solution introduction in plasma mass spectrometry using off-the-shelf commercial nebulizers

  5. Mass transfer ranking of polylysine, poly-ornithine and poly-methylene-co-guanidine microcapsule membranes using a single low molecular mass marker

    Directory of Open Access Journals (Sweden)

    Rosinski Stefan

    2003-01-01

    Full Text Available On the long way to clinical transplantable hybrid systems, comprising of cells, acting as immuno-protected bioreactors microencapsulated in a polymeric matrix and delivering desired factors (proteins, hormones, enzymes etc to the patient's body, an important step is the optimization of the microcapsule. This topic includes the selection of a proper coating membrane which could fulfil, first of all, the mass transfer as well as biocompatibility, stability and durability requirements. Three different membranes from polymerised aminoacids, formed around exactly identical alginate gel cores, were considered, concerning their mass transport properties, as potential candidates in this task. The results of the evaluation of the mass ingress and mass transfer coefficient h for the selected low molecular mass marker, vitamin B12, in poly-L-lysine (HPLL poly-L-ornithine (HPLO and poly-methylene-co-guanidine hydrochloride (HPMCG membrane alginate microcapsules demonstrate the advantage of using the mass transfer approach to a preliminary screening of various microcapsule formulations. Applying a single marker and evaluating mass transfer coefficients can help to quickly rank the investigated membranes and microcapsules according to their permeability. It has been demonstrated that HPLL, HPLO and HPMCG microcapsules differ from each other by a factor of two concerning the rate of low molecular mass marker transport. Interesting differences in mass transfer through the membrane in both directions in-out was also found, which could possibly be related to the membrane asymmetry.

  6. Mass spectrometric study of rhamnolipid biosurfactants and their interactions with cell membrane phospholipids

    Directory of Open Access Journals (Sweden)

    Pashynska V. A.

    2009-12-01

    Full Text Available Aim. To examine the formation of supramolecular complexes of biogenous rhamnolipids with membrane phospholipids that is considered as a molecular mechanism of the biosurfactants antimicrobial action. Method. In the present work rhamnolipid biosurfactant samples produced by Pseudomonas sp. PS-17 strain have been investigated by electrospray ionization mass spectrometry for the first time. Results. As a result of the study, characteristic mass spectra of the rhamnolipid samples were obtained, that can be used as reference spectra for mass spectrometric identification of the compounds in any biological or industrial samples. At the next stage of the experiments the pair systems, containing the biosurfactants and a membrane phospholipid dipalmitoylphosphatidylcholine, have been tested. The cationized noncovalent complexes of the rhamnolipids with the phospholipid were observed in the spectra. Conclusions. The results obtained testify to the consideration that rhamnolipids (similar to other membranotropic agents can form stable supramolecular complexes with membrane phospholipids that are able to evoke the biosurfactants antimicrobial action. A great potential of electrospray ionization mass spectrometry for the biosurfactants identification and study has been demonstrated in the work.

  7. The influence of polymeric membrane gas spargers on hydrodynamics and mass transfer in bubble column bioreactors.

    Science.gov (United States)

    Tirunehe, Gossaye; Norddahl, B

    2016-04-01

    Gas sparging performances of a flat sheet and tubular polymeric membranes were investigated in 3.1 m bubble column bioreactor operated in a semi batch mode. Air-water and air-CMC (Carboxymethyl cellulose) solutions of 0.5, 0.75 and 1.0 % w/w were used as interacting gas-liquid mediums. CMC solutions were employed in the study to simulate rheological properties of bioreactor broth. Gas holdup, bubble size distribution, interfacial area and gas-liquid mass transfer were studied in the homogeneous bubbly flow hydrodynamic regime with superficial gas velocity (U(G)) range of 0.0004-0.0025 m/s. The study indicated that the tubular membrane sparger produced the highest gas holdup and densely populated fine bubbles with narrow size distribution. An increase in liquid viscosity promoted a shift in bubble size distribution to large stable bubbles and smaller specific interfacial area. The tubular membrane sparger achieved greater interfacial area and an enhanced overall mass transfer coefficient (K(L)a) by a factor of 1.2-1.9 compared to the flat sheet membrane.

  8. Evaluation report on the R and D of the membrane separation process introduction technology; Makubunri process donyu gijutsu no kenkyu kaihatsu hyoka hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The paper reported the R and D of the membrane separation process introduction technology during a period of 1994 through 1998. The membrane separation technology is not associated with the phase change which requires large energy and expected to be an energy saving process. For the production of membranes required of high functions, the vapor deposition polymerization method was considered, and high order structure control of the membrane, control of adhesion and attachment, and control of orientation, and development of the high polymerization technology were required. For the high grade control of vapor polymerization, the substrate surface structure/quality were important. The molecular level analysis of the vapor deposition surface was also needed. Therefore, the paper took notice of STM (scanning tunneling microscopy), AFM (atomic force microscopy) and HREELS (high resolution electron energy loss spectroscopy) as surface atomic/molecular configuration analysis technology, and designed/fabricated and studied the high resolving power and high sensitivity analysis equipment using the analysis equipment which combined HREELS and STM and the analysis equipment using SFG (sum frequency generation) which can detect signals in the low frequency region. Making full use of the highest technology, technology was able to be developed for substrate surface analysis and surface reaction analysis technologies which become the basis of the high performance separation membrane fabrication technology by the vapor deposition polymerization method indispensable for introduction of the membrane separation process. The technology can be the base applicable to a lot of fields where surfaces and interfaces are concerned

  9. Profiling of integral membrane proteins and their post translational modifications using high-resolution mass spectrometry

    Science.gov (United States)

    Souda, Puneet; Ryan, Christopher M.; Cramer, William A.; Whitelegge, Julian

    2011-01-01

    Integral membrane proteins pose challenges to traditional proteomics approaches due to unique physicochemical properties including hydrophobic transmembrane domains that limit solubility in aqueous solvents. A well resolved intact protein molecular mass profile defines a protein’s native covalent state including post-translational modifications, and is thus a vital measurement toward full structure determination. Both soluble loop regions and transmembrane regions potentially contain post-translational modifications that must be characterized if the covalent primary structure of a membrane protein is to be defined. This goal has been achieved using electrospray-ionization mass spectrometry (ESI-MS) with low-resolution mass analyzers for intact protein profiling, and high-resolution instruments for top-down experiments, toward complete covalent primary structure information. In top-down, the intact protein profile is supplemented by gas-phase fragmentation of the intact protein, including its transmembrane regions, using collisionally activated and/or electroncapture dissociation (CAD/ECD) to yield sequence-dependent high-resolution MS information. Dedicated liquid chromatography systems with aqueous/organic solvent mixtures were developed allowing us to demonstrate that polytopic integral membrane proteins are amenable to ESI-MS analysis, including top-down measurements. Covalent post-translational modifications are localized regardless of their position in transmembrane domains. Top-down measurements provide a more detail oriented high-resolution description of post-transcriptional and post-translational diversity for enhanced understanding beyond genomic translation. PMID:21982782

  10. Dynamic analysis of CO₂ labeling and cell respiration using membrane-inlet mass spectrometry.

    Science.gov (United States)

    Yang, Tae Hoon

    2014-01-01

    Here, we introduce a mass spectrometry-based analytical method and relevant technical details for dynamic cell respiration and CO2 labeling analysis. Such measurements can be utilized as additional information and constraints for model-based (13)C metabolic flux analysis. Dissolved dynamics of oxygen consumption and CO2 mass isotopomer evolution from (13)C-labeled tracer substrates through different cellular processes can be precisely measured on-line using a miniaturized reactor system equipped with a membrane-inlet mass spectrometer. The corresponding specific rates of physiologically relevant gases and CO2 mass isotopomers can be quantified within a short-term range based on the liquid-phase dynamics of dissolved fermentation gases.

  11. Mass transport of direct methanol fuel cell species in sulfonated poly(ether ether ketone) membranes

    International Nuclear Information System (INIS)

    Silva, V.S.; Ruffmann, B.; Vetter, S.; Boaventura, M.; Mendes, A.M.; Madeira, L.M.; Nunes, S.P.

    2006-01-01

    Homogeneous membranes based on sulfonated poly(ether ether ketone) (sPEEK) with different sulfonation degrees (SD) were prepared and characterized. In order to perform a critical analysis of the SD effect on the polymer barrier and mass transport properties towards direct methanol fuel cell species, proton conductivity, water/methanol pervaporation and nitrogen/oxygen/carbon dioxide pressure rise method experiments are proposed. This procedure allows the evaluation of the individual permeability coefficients in hydrated sPEEK membranes with different sulfonation degrees. Nafion[reg] 112 was used as reference material. DMFC tests were also performed at 50 deg. C. It was observed that the proton conductivity and the permeability towards water, methanol, oxygen and carbon dioxide increase with the sPEEK sulfonation degree. In contrast, the SD seems to not affect the nitrogen permeability coefficient. In terms of selectivity, it was observed that the carbon dioxide/oxygen selectivity increases with the sPEEK SD. In contrast, the nitrogen/oxygen selectivity decreases. In terms of barrier properties for preventing the DMFC reactants loss, the polymer electrolyte membrane based on the sulfonated poly(ether ether ketone) with SD lower or equal to 71%, although having slightly lower proton conductivity, presented much better characteristics for fuel cell applications compared with the well known Nafion[reg] 112. In terms of the DMFC tests of the studied membranes at low temperature, the sPEEK membrane with SD = 71% showed to have similar performance, or even better, as that of Nafion[reg] 112. However, the highest DMFC overall efficiency was achieved using sPEEK membrane with SD = 52%

  12. Identification of membrane proteins by tandem mass spectrometry of protein ions

    Science.gov (United States)

    Carroll, Joe; Altman, Matthew C.; Fearnley, Ian M.; Walker, John E.

    2007-01-01

    The most common way of identifying proteins in proteomic analyses is to use short segments of sequence (“tags”) determined by mass spectrometric analysis of proteolytic fragments. The approach is effective with globular proteins and with membrane proteins with significant polar segments between membrane-spanning α-helices, but it is ineffective with other hydrophobic proteins where protease cleavage sites are either infrequent or absent. By developing methods to purify hydrophobic proteins in organic solvents and by fragmenting ions of these proteins by collision induced dissociation with argon, we have shown that partial sequences of many membrane proteins can be deduced easily by manual inspection. The spectra from small proteolipids (1–4 transmembrane α-helices) are dominated usually by fragment ions arising from internal amide cleavages, from which internal sequences can be obtained, whereas the spectra from larger membrane proteins (5–18 transmembrane α-helices) often contain fragment ions from N- and/or C-terminal parts yielding sequences in those regions. With these techniques, we have, for example, identified an abundant protein of unknown function from inner membranes of mitochondria that to our knowledge has escaped detection in proteomic studies, and we have produced sequences from 10 of 13 proteins encoded in mitochondrial DNA. They include the ND6 subunit of complex I, the last of its 45 subunits to be analyzed. The procedures have the potential to be developed further, for example by using newly introduced methods for protein ion dissociation to induce fragmentation of internal regions of large membrane proteins, which may remain partially folded in the gas phase. PMID:17720804

  13. Determining Membrane Protein-Lipid Binding Thermodynamics Using Native Mass Spectrometry.

    Science.gov (United States)

    Cong, Xiao; Liu, Yang; Liu, Wen; Liang, Xiaowen; Russell, David H; Laganowsky, Arthur

    2016-04-06

    Membrane proteins are embedded in the biological membrane where the chemically diverse lipid environment can modulate their structure and function. However, the thermodynamics governing the molecular recognition and interaction of lipids with membrane proteins is poorly understood. Here, we report a method using native mass spectrometry (MS), to determine thermodynamics of individual ligand binding events to proteins. Unlike conventional methods, native MS can resolve individual ligand binding events and, coupled with an apparatus to control the temperature, determine binding thermodynamic parameters, such as for protein-lipid interactions. We validated our approach using three soluble protein-ligand systems (maltose binding protein, lysozyme, and nitrogen regulatory protein) and obtained similar results to those using isothermal titration calorimetry and surface plasmon resonance. We also determined for the first time the thermodynamics of individual lipid binding to the ammonia channel (AmtB), an integral membrane protein from Escherichia coli. Remarkably, we observed distinct thermodynamic signatures for the binding of different lipids and entropy-enthalpy compensation for binding lipids of variable chain length. Additionally, using a mutant form of AmtB that abolishes a specific phosphatidylglycerol (PG) binding site, we observed distinct changes in the thermodynamic signatures for binding PG, implying these signatures can identify key residues involved in specific lipid binding and potentially differentiate between specific lipid binding sites.

  14. Experimental study on mass transfer of contaminants through an enthalpy recovery unit with polymer membrane foils

    DEFF Research Database (Denmark)

    Nie, Jinzhe; Fang, Lei

    2014-01-01

    Laboratory experimental studies were conducted to investigate the mass transfer of contaminants through a total heat recovery unit with polymer membranes foils. The studies were conducted in twin climate chambers which simulated outdoor and indoor thermal climates. One manufacturd total heat...... chemical gases were used to simulate air contaminants. The concentrations of dosed contaminants in the supply and exhaust air upstream and downstream of the total heat recovery unit were measured with Multi-Gas Monitor Innova 1316 in real time. Experiment results showed that 5% to 9% of dosed contaminants...... could transfer from exhaust air to supply air through the enthalpy recovery unit. The mass transfer efficiency of contaminants was independent of the hygro-thermal differences between indoor and outdoor climate conditions. The mass transfer ratio of the chemical contaminants in the total heat recovery...

  15. DETERMINATION OF THE MASS TRANSFER CHARACTERIZATION OF A CERAMIC-POLYMER COMPOSITE MEMBRANE IN THE PERVAPORATION MODE

    Science.gov (United States)

    The effect of the coating layer thickness on VOC extraction performance of a ceramic polymer composite membrane has been investigated. It was found, under experimental condiitons representing typical field operation, the overall mass transfer rates of feed components were control...

  16. Osmotic Power Generation by Inner Selective Hollow Fiber Membranes: An investigation of thermodynamics, mass transfer, and module scale modelling

    KAUST Repository

    Xiong, Jun Ying; Cai, Dong Jun; Chong, Qing Yu; Lee, Swin Hui; Chung, Neal Tai-Shung

    2016-01-01

    A comprehensive analysis of fluid motion, mass transport, thermodynamics and power generation during pressure retarded osmotic (PRO) processes was conducted. This work aims to (1) elucidate the fundamental relationship among various membrane

  17. Application of the mass-based UNIQUAC model to membrane systems: A critical revision

    International Nuclear Information System (INIS)

    Chovau, S.; Van der Bruggen, B.; Luis, P.

    2012-01-01

    Highlights: ► UNIQUAC model in mass-based terms is considered for the description of sorption equilibria in membrane systems. ► Model validation of molar and mass-based model is performed on simple (vapor + liquid) equilibrium. ► Discrepancy is found between molar and mass-based model, which is attributed to an incorrect conversion. ► Novel model based on correct thermodynamics is provided for future research. - Abstract: The UNIQUAC model is very suitable in describing (liquid + liquid) as well as (vapor + liquid) equilibrium for a wide range of systems. It can be extended to (solvent + polymer) systems for describing sorption equilibria. The original model is expressed in molar-based terms, but requires knowledge of structural parameters and molar masses of all components. Since these cannot always be easily determined for membranes, a conversion to mass-based terms is often performed, which eliminates this issue. Many studies use this model to calculate sorption equilibria in (solvent + polymer) systems. Nevertheless, in this work the conversion from molar to mass-based parameters is postulated to be erroneous. This even leads to an incorrect description of simple (vapor + liquid) equilibrium of pure liquid mixtures and hence it is advised not to use this model for further modeling of sorption equilibrium in (solvent + polymer) systems. In this paper, the errors in the conversion are pinpointed, and the effects it can have on the description of (vapor + liquid) equilibrium, if used improvident, are demonstrated. Furthermore, it is shown that in fact a simple and straightforward conversion can be performed. Finally, in the case when polymers are involved, an adaption and simplification to the model was successfully applied.

  18. Experimental study of laser ablation as sample introduction technique for inductively coupled plasma-mass spectrometry

    International Nuclear Information System (INIS)

    Van Winckel, S.

    2001-01-01

    The contribution consists of an abstract of a PhD thesis. In the PhD study, several complementary applications of laser-ablation were investigated in order to characterise experimentally laser ablation (LA) as a sample introduction technique for ICP-MS. Three applications of LA as a sample introduction technique are discussed: (1) the microchemical analysis of the patina of weathered marble; (2) the possibility to measure isotope ratios (in particular Pb isotope ratios in archaeological bronze artefacts); and (3) the determination of Si in Al as part of a dosimetric study of the BR2 reactor vessel

  19. Membrane inlet mass spectrometry reveals that Ceriporiopsis subvermispora bicupin oxalate oxidase is inhibited by nitric oxide.

    Science.gov (United States)

    Moomaw, Ellen W; Uberto, Richard; Tu, Chingkuang

    2014-07-18

    Membrane inlet mass spectrometry (MIMS) uses a semipermeable membrane as an inlet to a mass spectrometer for the measurement of the concentration of small uncharged molecules in solution. We report the use of MIMS to characterize the catalytic properties of oxalate oxidase (E.C. 1.2.3.4) from Ceriporiopsis subvermispora (CsOxOx). Oxalate oxidase is a manganese dependent enzyme that catalyzes the oxygen-dependent oxidation of oxalate to carbon dioxide in a reaction that is coupled with the formation of hydrogen peroxide. CsOxOx is the first bicupin enzyme identified that catalyzes this reaction. The MIMS method of measuring OxOx activity involves continuous, real-time direct detection of oxygen consumption and carbon dioxide production from the ion currents of their respective mass peaks. (13)C2-oxalate was used to allow for accurate detection of (13)CO2 (m/z 45) despite the presence of adventitious (12)CO2. Steady-state kinetic constants determined by MIMS are comparable to those obtained by a continuous spectrophotometric assay in which H2O2 production is coupled to the horseradish peroxidase catalyzed oxidation of 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid). Furthermore, we used MIMS to determine that NO inhibits the activity of the CsOxOx with a KI of 0.58±0.06 μM. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Chemical crosslinking and mass spectrometry studies of the structure and dynamics of membrane proteins and receptors.

    Energy Technology Data Exchange (ETDEWEB)

    Haskins, William E.; Leavell, Michael D.; Lane, Pamela; Jacobsen, Richard B.; Hong, Joohee; Ayson, Marites J.; Wood, Nichole L.; Schoeniger, Joseph S.; Kruppa, Gary Hermann; Sale, Kenneth L.; Young, Malin M.; Novak, Petr

    2005-03-01

    Membrane proteins make up a diverse and important subset of proteins for which structural information is limited. In this study, chemical cross-linking and mass spectrometry were used to explore the structure of the G-protein-coupled photoreceptor bovine rhodopsin in the dark-state conformation. All experiments were performed in rod outer segment membranes using amino acid 'handles' in the native protein sequence and thus minimizing perturbations to the native protein structure. Cysteine and lysine residues were covalently cross-linked using commercially available reagents with a range of linker arm lengths. Following chemical digestion of cross-linked protein, cross-linked peptides were identified by accurate mass measurement using liquid chromatography-fourier transform mass spectrometry and an automated data analysis pipeline. Assignments were confirmed and, if necessary, resolved, by tandem MS. The relative reactivity of lysine residues participating in cross-links was evaluated by labeling with NHS-esters. A distinct pattern of cross-link formation within the C-terminal domain, and between loop I and the C-terminal domain, emerged. Theoretical distances based on cross-linking were compared to inter-atomic distances determined from the energy-minimized X-ray crystal structure and Monte Carlo conformational search procedures. In general, the observed cross-links can be explained by re-positioning participating side-chains without significantly altering backbone structure. One exception, between C3 16 and K325, requires backbone motion to bring the reactive atoms into sufficient proximity for cross-linking. Evidence from other studies suggests that residues around K325 for a region of high backbone mobility. These findings show that cross-linking studies can provide insight into the structural dynamics of membrane proteins in their native environment.

  1. Reactions of nitrite with hemoglobin measured by membrane inlet mass spectrometry

    Science.gov (United States)

    Tu, Chingkuang; Mikulski, Rose; Swenson, Erik R.; Silverman, David N.

    2010-01-01

    Membrane inlet mass spectrometry was used to observe nitric oxide in the well-studied reaction of nitrite with hemoglobin. The membrane inlet was submerged in the reaction solutions and measured NO in solution via its flux across a semipermeable membrane leading to the mass spectrometer detecting the mass-to-charge ratio m/z 30. This method measures NO directly in solution and is an alternate approach compared with methods that purge solutions to measure NO. Addition to deoxy-Hb(FeII) (near 38 µM heme concentration) of nitrite in a range of 80 µM to 16 mM showed no accumulation of either NO or N2O3 on a physiologically relevant time scale with a sensitivity near 1 nM. The addition of nitrite to oxy-Hb(FeII) and met-Hb(FeIII) did not accumulate free NO to appreciable extents. These observations show that for several minutes after mixing nitrite with hemoglogin, free NO does not accumulate to levels exceeding the equilibrium level of NO. The presence of cyanide ions did not alter the appearance of the data; however, the presence of 2 mM mercuric ions at the beginning of the experiment with deoxy-Hb(FeII) shortened the initial phase of NO accumulation and increased the maximal level of free, unbound NO by about twofold. These experiments appear consistent with no role of met-Hb(FeIII) in the generation of NO and an increase in nitrite reductase activity caused by the presumed binding of mercuric to cysteine residues. These results raise questions about the ability of reduction of nitrite mediated by deoxy-Hb(FeII) to play a role in vasodilation. PMID:18848984

  2. Comparison of Theoretical and Experimental Mass Transfer Coefficients of Gases in Supported Ionic Liquid Membranes

    Czech Academy of Sciences Publication Activity Database

    Kárászová, Magda; Šimčík, Miroslav; Friess, K.; Randová, A.; Jansen, J. C.; Růžička, Marek; Sedláková, Zuzana; Izák, Pavel

    2013-01-01

    Roč. 118, 30 OCT (2013), s. 255-263 ISSN 1383-5866 R&D Projects: GA ČR GAP106/10/1194; GA MŠk(CZ) 7C11009 Grant - others:RFCS(XE) RFCR-CT-2010-00009; INP(IT) PON01_01840; HA MŠk(CZ) CZ.1.05/2.1.00/03.0071 Institutional support: RVO:67985858 Keywords : biogas purification * supported ionic liquid membranes * mass transfer coefficients Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 3.065, year: 2013

  3. NGVS. Challenges for the Japanese gas industry to open the door for their mass introduction

    International Nuclear Information System (INIS)

    Akimoto, Minoru; Kawamoto, Hiroshi; Suzuki, Tatsuya; Yamaguchi, Eiji

    1997-01-01

    There have been a number of restraints in Japan delaying the introduction of natural gas vehicles (NGVs), which is a new comer in car industry. The Japanese gas industry, with support from government agencies, has conducted feasibility studies and clarified necessary technical and safety standards and regulations. These efforts have contributed to the government's drive for deregulation. Concurrently, the gas industry worked out its own scenarios for the promotion of NGVs in Japan, which helped the government in laying down necessary regulations and establishing clear market objectives for the vehicles as government policies. Such activities have yielded model introduction by the national and local governments and government-sponsored incentives for NGV promotion. For auto manufacturers, the gas industry proposed joint development projects and clarified potential market for NGVs. Consequently, many manufactures are now involved in their own NGV development projects. (au)

  4. Influence of high range of mass transfer coefficient and convection heat transfer on direct contact membrane distillation performance

    KAUST Repository

    Lee, Jung Gil

    2017-11-03

    In order to improve water production of membrane distillation (MD), the development of high performance membrane having better mass transfer and enhancement of convection heat transfer in MD module have been continuously investigated. This paper presents the relationship between the heat and mass transfer resistance across the membrane and the performance improvement. Various ranges of mass transfer coefficient (MTC) from normal (0.3×10−6 to 2.1×10−6kg/m2sPa: currently available membranes) to high (>2.1×10−6kg/m2sPa: membranes under development) were simulated using an experimentally validated model at different ranges of convection heat transfer by varying the inlet flow rates and spacer enhancement factor. The effect of mass transfer and convection heat transfer on the MD performance parameters including temperature polarization coefficient (TPC), mean permeate flux, and specific energy consumption were investigated in a direct contact MD (DCMD) configuration. Results showed that improving the MTC at the low ranges is more important than that at the high ranges where the heat transfer resistance becomes dominant and hence the convection heat transfer coefficient must be increased. Therefore, an effort on designing MD modules using feed and permeate spacers and controlling the membrane surface roughness to increase the convection heat transfer and TPC in the channel aiming to enhance the flux is required because the currently developed mass transfer has almost reached the critical point.

  5. Automated sample preparation using membrane microtiter extraction for bioanalytical mass spectrometry.

    Science.gov (United States)

    Janiszewski, J; Schneider, P; Hoffmaster, K; Swyden, M; Wells, D; Fouda, H

    1997-01-01

    The development and application of membrane solid phase extraction (SPE) in 96-well microtiter plate format is described for the automated analysis of drugs in biological fluids. The small bed volume of the membrane allows elution of the analyte in a very small solvent volume, permitting direct HPLC injection and negating the need for the time consuming solvent evaporation step. A programmable liquid handling station (Quadra 96) was modified to automate all SPE steps. To avoid drying of the SPE bed and to enhance the analytical precision a novel protocol for performing the condition, load and wash steps in rapid succession was utilized. A block of 96 samples can now be extracted in 10 min., about 30 times faster than manual solvent extraction or single cartridge SPE methods. This processing speed complements the high-throughput speed of contemporary high performance liquid chromatography mass spectrometry (HPLC/MS) analysis. The quantitative analysis of a test analyte (Ziprasidone) in plasma demonstrates the utility and throughput of membrane SPE in combination with HPLC/MS. The results obtained with the current automated procedure compare favorably with those obtained using solvent and traditional solid phase extraction methods. The method has been used for the analysis of numerous drug prototypes in biological fluids to support drug discovery efforts.

  6. Introduction to chemistry and applications in nature of mass independent isotope effects special feature.

    Science.gov (United States)

    Thiemens, Mark H

    2013-10-29

    Stable isotope ratio variations are regulated by physical and chemical laws. These rules depend on a relation with mass differences between isotopes. New classes of isotope variation effects that deviate from mass dependent laws, termed mass independent isotope effects, were discovered in 1983 and have a wide range of applications in basic chemistry and nature. In this special edition, new applications of these effects to physical chemistry, solar system origin models, terrestrial atmospheric and biogenic evolution, polar paleo climatology, snowball earth geology, and present day atmospheric sciences are presented.

  7. Introduction to computer control and future aspects in thermal ionisation mass spectrometry

    International Nuclear Information System (INIS)

    Hagemann, R.

    The author considers the computer control of the measurement program which is already available in modern mass spectrometers. Future areas for computer control are considered e.g. the heating program, ion optics and focusing, and sample changer control. (Auth.)

  8. Introduction to computer control and future aspects in thermal ionisation mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Hagemann, R. [CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1978-12-15

    The author considers the computer control of the measurement program which is already available in modern mass spectrometers. Future areas for computer control are considered e.g. the heating program, ion optics and focusing, and sample changer control.

  9. Mass spectrometer introduction line: application to the analysis of impurities in uranium hexafluoride; Ligne d'introduction pour spectrometre de masse: application a l'analyse des impuretes contenues dans l'UF{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Besson, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires. Departement de physico-chimie, service des isotopes stables, section de spectrometrie de masse

    1967-01-01

    The continuous mass-spectrometric analysis of impurities in UF{sub 6} is possible industrially if certain conditions imposed by the nature of the gas are respected. The gas introduction line arriving at the spectrometer's source makes it possible to fix the flow-rate, to control the inlet pressure and to selectively destroy the gas containing the impurities. The operational conditions for the line are defined and a description is given of the theoretical and experimental study of the various elements of which it is composed, i.e. the leak valve, the flow-meter, the chemical trap and the servo-mechanism making it possible to regulate and control the gas flow. The dynamic characteristics of the line's various components and the performance of the equipment in the case of the analyses considered are given. (author) [French] L'analyse en continu par spectrometrie de masse des impuretes contenus dans l'UF{sub 6} est possible industriellement moyennant certaines conditions imposees par la nature du gaz. La ligne d'introduction des gaz dans la source du spectrometre permet de regler le debit, de controler la pression d'introduction et de detruire selectivement le gaz porteur d'impuretes. Les conditions de fonctionnement de la ligne etant definies, on decrit l'etude theorique et experimentale des differents elements qui la composent, c'est-a-dire: le robinet a fuite, le debitmetre, le piege chimique et l'ensemble d'asservissement permettant la regulation et le controle du debit. On donne les caracteristiques dynamiques des differents constituants de la ligne et les performances de l'ensemble pour les analyses considerees. (auteur)

  10. Mass spectrometer introduction line: application to the analysis of impurities in uranium hexafluoride; Ligne d'introduction pour spectrometre de masse: application a l'analyse des impuretes contenues dans l'UF{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Besson, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires. Departement de physico-chimie, service des isotopes stables, section de spectrometrie de masse

    1967-01-01

    The continuous mass-spectrometric analysis of impurities in UF{sub 6} is possible industrially if certain conditions imposed by the nature of the gas are respected. The gas introduction line arriving at the spectrometer's source makes it possible to fix the flow-rate, to control the inlet pressure and to selectively destroy the gas containing the impurities. The operational conditions for the line are defined and a description is given of the theoretical and experimental study of the various elements of which it is composed, i.e. the leak valve, the flow-meter, the chemical trap and the servo-mechanism making it possible to regulate and control the gas flow. The dynamic characteristics of the line's various components and the performance of the equipment in the case of the analyses considered are given. (author) [French] L'analyse en continu par spectrometrie de masse des impuretes contenus dans l'UF{sub 6} est possible industriellement moyennant certaines conditions imposees par la nature du gaz. La ligne d'introduction des gaz dans la source du spectrometre permet de regler le debit, de controler la pression d'introduction et de detruire selectivement le gaz porteur d'impuretes. Les conditions de fonctionnement de la ligne etant definies, on decrit l'etude theorique et experimentale des differents elements qui la composent, c'est-a-dire: le robinet a fuite, le debitmetre, le piege chimique et l'ensemble d'asservissement permettant la regulation et le controle du debit. On donne les caracteristiques dynamiques des differents constituants de la ligne et les performances de l'ensemble pour les analyses considerees. (auteur)

  11. Large-scale analysis of in Vivo phosphorylated membrane proteins by immobilized metal ion affinity chromatography and mass spectrometry

    DEFF Research Database (Denmark)

    Nühse, Thomas S; Stensballe, Allan; Jensen, Ole N

    2003-01-01

    specificity. We investigated the potential of IMAC in combination with capillary liquid chromatography coupled to tandem mass spectrometry for the identification of plasma membrane phosphoproteins of Arabidopsis. Without chemical modification of peptides, over 75% pure phosphopeptides were isolated from...... plasma membrane digests and detected and sequenced by mass spectrometry. We present a scheme for two-dimensional peptide separation using strong anion exchange chromatography prior to IMAC that both decreases the complexity of IMAC-purified phosphopeptides and yields a far greater coverage...... of monophosphorylated peptides. Among the identified sequences, six originated from different isoforms of the plasma membrane H(+)-ATPase and defined two previously unknown phosphorylation sites at the regulatory C terminus. The potential for large-scale identification of phosphorylation sites on plasma membrane...

  12. INTRODUCTION: Theoretical Models as Mass Media Practice: Perspectives from the West

    DEFF Research Database (Denmark)

    Thomsen, Line

    2007-01-01

    What is journalism? How does it exist and why? How does journalism define itself and in what ways can we make use of looking theoretically at the practice of it? These were the central themes of our workshop; Theoretical Models as Mass Media Practice held at the ‘Minding the Gap’ conference...... an exceptional framework for understanding the workings of mass media while helping the press reflect over these workings too. In a time of change for the journalistic profession, when media convergence is growing; the media is marked by deregulation and fewer journalists are being asked to do more...... at Reuters Institute in May 2007, from which this collection of papers has been selected. As with the other workshops during the conference, the majority of our panellists were themselves once media practitioners. It is my opinion that this background and inside knowledge of the field in itself can provide...

  13. On the numerical computation of Q.C.D. mass spectrum: an introduction

    International Nuclear Information System (INIS)

    Marinari, E.

    1983-09-01

    Exploiting MC techniques for analyzing a lattice gauge theory coupled to fermionic matter fields, we just quote here the 3 main difficulties: first the anticommuting character of the fermionic fields, implying a strong non locality of the effective action, obtained by integrating out the fermionic fields. The second point is that the bare quark mass is not allowed, on a finite lattice, to be arbitrarily small: it is controlling the correlation length of the fermionic sector of the theory. The possible way out consists in working with unphysically large quark masses, and eventually trying to extrapolate. Last we have to face the so called doubling problem: the discretization of the continuum theory makes a number of unwanted fermionic species appearing, and/or explicitly breaks the chiral invariance of the theory

  14. Introduction to numerical modeling of thermohydrologic flow in fractured rock masses

    International Nuclear Information System (INIS)

    Wang, J.S.Y.

    1980-01-01

    More attention is being given to the possibility of nuclear waste isolation in hard rock formations. The waste will generate heat which raises the temperature of the surrounding fractured rock masses and induces buoyancy flow and pressure change in the fluid. These effects introduce the potential hazard of radionuclides being carried to the biosphere, and affect the structure of a repository by stress changes in the rock formation. The thermohydrological and thermomechanical responses are determined by the fractures as well as the intact rock blocks. The capability of modeling fractured rock masses is essential to site characterization and repository evaluation. The fractures can be modeled either as a discrete system, taking into account the detailed fracture distributions, or as a continuum representing the spatial average of the fractures. A numerical model is characterized by the governing equations, the numerical methods, the computer codes, the validations, and the applications. These elements of the thermohydrological models are discussed. Along with the general review, some of the considerations in modeling fractures are also discussed. Some remarks on the research needs in modeling fractured rock mass conclude the paper

  15. Hydrogen Exchange Mass Spectrometry of Functional Membrane-bound Chemotaxis Receptor Complexes

    Science.gov (United States)

    Koshy, Seena S.; Eyles, Stephen J.; Weis, Robert M.; Thompson, Lynmarie K.

    2014-01-01

    The transmembrane signaling mechanism of bacterial chemotaxis receptors is thought to involve changes in receptor conformation and dynamics. The receptors function in ternary complexes with two other proteins, CheA and CheW, that form extended membrane-bound arrays. Previous studies have shown that attractant binding induces a small (~2 Å) piston displacement of one helix of the periplasmic and transmembrane domains towards the cytoplasm, but it is not clear how this signal propagates through the cytoplasmic domain to control the kinase activity of the CheA bound at the membrane-distal tip, nearly 200 Å away. The cytoplasmic domain has been shown to be highly dynamic, which raises the question of how a small piston motion could propagate through a dynamic domain to control CheA kinase activity. To address this, we have developed a method for measuring dynamics of the receptor cytoplasmic fragment (CF) in functional complexes with CheA and CheW. Hydrogen exchange mass spectrometry (HDX-MS) measurements of global exchange of CF demonstrate that CF exhibits significantly slower exchange in functional complexes than in solution. Since the exchange rates in functional complexes are comparable to that of other proteins of similar structure, the CF appears to be a well-structured protein within these complexes, which is compatible with its role in propagating a signal that appears to be a tiny conformational change in the periplasmic and transmembrane domains of the receptor. We also demonstrate the feasibility of this protocol for local exchange measurements, by incorporating a pepsin digest step to produce peptides with 87% sequence coverage and only 20% back exchange. This method extends HDX-MS to membrane-bound functional complexes without detergents that may perturb the stability or structure of the system. PMID:24274333

  16. Kinetics of americium(VI) mass transfer through solid supported liquid membrane with HDEHP

    International Nuclear Information System (INIS)

    Mikheeva, M.N.; Novicoov, P.; Myasoedov, B.F.; Tikhomirov, S.V.

    1994-01-01

    The main regularities of membrane extraction of americium under conditions of different redox potentials in aqueous phases have been studied. The physico-chemical model of the process including steps of americium oxidation in feed solution, extraction by membrane, partial reduction on membrane surface, trans-membrane diffusion and reextraction to strip solution has been developed. The calculation of reduction rate constant on membrane surface has been carried out. (author) 9 refs.; 4 figs.; 3 tabs

  17. Electroerosion of metal in aqueous solution for sample introduction into an inductively coupled plasma mass spectrometer

    International Nuclear Information System (INIS)

    Goltz, Douglas; Boileau, Michael; Reinfelds, Gundars

    2003-01-01

    When high current (1-10 A cm -2 ) is applied between two conductive samples (metals) in aqueous solution, electroerosion occurs on the surface as a result of electrolysis and possibly collisions of dissolved ions with the metal surface. The power supply for the electroerosion apparatus in this work was a modified spark source unit. Current could be varied in intervals of 2.5, 5 and 10 A in either half-wave (unipolar) or full-wave (bipolar) output. The electroeroded metal forms a colloidal suspension in aqueous solution with particle sizes of the order of 1-10 μm and possibly larger. The suspension is readily dissolved using a small amount (100 μl) of concentrated acid (HCl or HNO 3 ) prior to analysis. Electroerosion of steel and brass in aqueous solution is described both for rapid sample dissolution and as a solid sampling approach for ICP-MS. Some of the electroerosion properties described in this paper include rates of erosion as a function of gap between the conductive samples and solution conductivity. Rates of electroerosion decreased from 120 to 30 μg s -1 as the gap was increased from 2 to 5 mm. Rates of electroerosion also increased significantly from 200 to 1000 μg s -1 as the conductivity of the electroerosion solution increased from 0.01 to 0.05 M NaCl. Interfacing the electroerosion apparatus to an ICP-MS was straight forward, as no special equipment was required. Therefore, the electroerosion apparatus can be used for rapid 'on-line' sample dissolution prior to introduction into an ICP. ICP-MS time profiles of selected metals in stainless steel 308L illustrate the behavior of 52 Cr + , 55 Mn + and 60 Ni + during a typical electroerosion cycle. Aspiration of the colloidal suspension into the ICP did not appear to load the plasma significantly, however, all of the metals produced noisy signals (±10%). A glass concentric nebulizer was used without clogging, so it is likely that the heterogeneous nature of the colloidal suspension caused this effect

  18. Electroerosion of metal in aqueous solution for sample introduction into an inductively coupled plasma mass spectrometer

    Science.gov (United States)

    Goltz, Douglas; Boileau, Michael; Reinfelds, Gundars

    2003-07-01

    When high current (1-10 A cm -2) is applied between two conductive samples (metals) in aqueous solution, electroerosion occurs on the surface as a result of electrolysis and possibly collisions of dissolved ions with the metal surface. The power supply for the electroerosion apparatus in this work was a modified spark source unit. Current could be varied in intervals of 2.5, 5 and 10 A in either half-wave (unipolar) or full-wave (bipolar) output. The electroeroded metal forms a colloidal suspension in aqueous solution with particle sizes of the order of 1-10 μm and possibly larger. The suspension is readily dissolved using a small amount (100 μl) of concentrated acid (HCl or HNO 3) prior to analysis. Electroerosion of steel and brass in aqueous solution is described both for rapid sample dissolution and as a solid sampling approach for ICP-MS. Some of the electroerosion properties described in this paper include rates of erosion as a function of gap between the conductive samples and solution conductivity. Rates of electroerosion decreased from 120 to 30 μg s -1 as the gap was increased from 2 to 5 mm. Rates of electroerosion also increased significantly from 200 to 1000 μg s -1 as the conductivity of the electroerosion solution increased from 0.01 to 0.05 M NaCl. Interfacing the electroerosion apparatus to an ICP-MS was straight forward, as no special equipment was required. Therefore, the electroerosion apparatus can be used for rapid 'on-line' sample dissolution prior to introduction into an ICP. ICP-MS time profiles of selected metals in stainless steel 308L illustrate the behavior of 52Cr +, 55Mn + and 60Ni + during a typical electroerosion cycle. Aspiration of the colloidal suspension into the ICP did not appear to load the plasma significantly, however, all of the metals produced noisy signals (±10%). A glass concentric nebulizer was used without clogging, so it is likely that the heterogeneous nature of the colloidal suspension caused this effect.

  19. Electroerosion of metal in aqueous solution for sample introduction into an inductively coupled plasma mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Goltz, Douglas E-mail: dgoltz@uwinnipeg.ca; Boileau, Michael; Reinfelds, Gundars

    2003-07-18

    When high current (1-10 A cm{sup -2}) is applied between two conductive samples (metals) in aqueous solution, electroerosion occurs on the surface as a result of electrolysis and possibly collisions of dissolved ions with the metal surface. The power supply for the electroerosion apparatus in this work was a modified spark source unit. Current could be varied in intervals of 2.5, 5 and 10 A in either half-wave (unipolar) or full-wave (bipolar) output. The electroeroded metal forms a colloidal suspension in aqueous solution with particle sizes of the order of 1-10 {mu}m and possibly larger. The suspension is readily dissolved using a small amount (100 {mu}l) of concentrated acid (HCl or HNO{sub 3}) prior to analysis. Electroerosion of steel and brass in aqueous solution is described both for rapid sample dissolution and as a solid sampling approach for ICP-MS. Some of the electroerosion properties described in this paper include rates of erosion as a function of gap between the conductive samples and solution conductivity. Rates of electroerosion decreased from 120 to 30 {mu}g s{sup -1} as the gap was increased from 2 to 5 mm. Rates of electroerosion also increased significantly from 200 to 1000 {mu}g s{sup -1} as the conductivity of the electroerosion solution increased from 0.01 to 0.05 M NaCl. Interfacing the electroerosion apparatus to an ICP-MS was straight forward, as no special equipment was required. Therefore, the electroerosion apparatus can be used for rapid 'on-line' sample dissolution prior to introduction into an ICP. ICP-MS time profiles of selected metals in stainless steel 308L illustrate the behavior of {sup 52}Cr{sup +}, {sup 55}Mn{sup +} and {sup 60}Ni{sup +} during a typical electroerosion cycle. Aspiration of the colloidal suspension into the ICP did not appear to load the plasma significantly, however, all of the metals produced noisy signals ({+-}10%). A glass concentric nebulizer was used without clogging, so it is likely that the

  20. Direct sample introduction-gas chromatography-mass spectrometry for the determination of haloanisole compounds in cork stoppers.

    Science.gov (United States)

    Cacho, J I; Nicolás, J; Viñas, P; Campillo, N; Hernández-Córdoba, M

    2016-12-02

    A solventless analytical method is proposed for analyzing the compounds responsible for cork taint in cork stoppers. Direct sample introduction (DSI) is evaluated as a sample introduction system for the gas chromatography-mass spectrometry (GC-MS) determination of four haloanisoles (HAs) in cork samples. Several parameters affecting the DSI step, including desorption temperature and time, gas flow rate and other focusing parameters, were optimized using univariate and multivariate approaches. The proposed method shows high sensitivity and minimises sample handling, with detection limits of 1.6-2.6ngg -1 , depending on the compound. The suitability of the optimized procedure as a screening method was evaluated by obtaining decision limits (CCα) and detection capabilities (CCβ) for each analyte, which were found to be in 6.9-11.8 and 8.7-14.8ngg -1 , respectively, depending on the compound. Twenty-four cork samples were analysed, and 2,4,6-trichloroanisole was found in four of them at levels between 12.6 and 53ngg -1 . Copyright © 2016 Elsevier B.V. All rights reserved.

  1. The transuranic mass balance during the introduction of metal fuel FBR cycle

    International Nuclear Information System (INIS)

    Yokoo, Takeshi; Inoue, Tadashi

    1999-01-01

    The mass flow of plutonium and minor actinides is calculated for a future light water reactor-fast breeder reactor (LWR-FBR) transition scenario, in which power generation by LWRs is continued on a certain scale for a long period before the replacement by FBRs begins. The burnup of the LWR spent fuel is considered to be higher than the current standard. It is assumed that all the plutonium and minor actinides recovered from LWRs are used to start up and feed metal fuel commercial FBRs, which replace those LWRs that have reached the end of their life. The results show that the accumulated plutonium and minor actinides from the LWRs can be consistently consumed without further accumulation, by gradually establishing the FBR power generation and its fuel cycle on the same scale. The optimum content of the minor actinides in the standard FBR fuel is about 2 weight percents. This result indicates that if FBRs are introduced in the future, extension of the LWR usage period will cause no significant problems in terms of the consumption of accumulated transuranic elements. (author)

  2. Elucidation and identification of amino acid containing membrane lipids using liquid chromatography/high-resolution mass spectrometry

    NARCIS (Netherlands)

    Moore, E.K.; Hopmans, E.C.; Rijpstra, W.I.C.; Villanueva, L.; Sinninghe Damsté, J.S.

    2016-01-01

    RATIONALE: Intact polar lipids (IPLs) are the building blocks of cell membranes, and amino acid containing IPLs havebeen observed to be involved in response to changing environmental conditions in various species of bacteri a. High-performance liquid chromatography/mass spectrometry (HPLC/MS) has

  3. Influence of high range of mass transfer coefficient and convection heat transfer on direct contact membrane distillation performance

    KAUST Repository

    Lee, Jung Gil; Jeong, Sanghyun; Alsaadi, Ahmad Salem; Ghaffour, NorEddine

    2017-01-01

    (>2.1×10−6kg/m2sPa: membranes under development) were simulated using an experimentally validated model at different ranges of convection heat transfer by varying the inlet flow rates and spacer enhancement factor. The effect of mass transfer

  4. Novel protein phosphorylation site identification in spinach stroma membranes by titanium dioxide microcolumns and tandem mass spectrometry

    DEFF Research Database (Denmark)

    Rinalducci, Sara; Larsen, Martin Røssel; Mohammed, Shabaz

    2006-01-01

    In this work, spinach stroma membrane, instead of thylakoid, has been investigated for the presence of phosphorylated proteins. We identified seven previously unknown phosphorylation sites by taking advantage of TiO(2) phosphopeptides enrichment coupled to mass spectrometric analysis. Upon...

  5. Investigations on the direct introduction of cigarette smoke for trace elements analysis by inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Chang, Michael J.; Naworal, John D.; Walker, Kathleen; Connell, Chris T.

    2003-01-01

    Direct introduction of mainstream cigarette smoke into an inductively coupled plasma mass spectrometry (ICP-MS) has been investigated with respect to its feasibility for on-line analysis of trace elements. An automated apparatus was designed and built interfacing a smoking machine with an ICP-MS for smoke generation, collection, injection and analysis. Major and minor elements present in the particulate phase and the gas phase of mainstream cigarette smoke of 2R4F reference cigarettes have been qualitatively identified by examination of their full mass spectra. This method provides a rapid-screening analysis of the transfer of trace elements into mainstream smoke during cigarette combustion. A full suite of elements present in the whole cigarette smoke has been identified, including As, B, Ba, Br, Cd, Cl, Cs, Cu, Hg, I, K, Li, Mn, Na, Pb, Rb, Sb, Sn, Tl and Zn. Of these elements, the major portions of B, Ba, Cs, Cu, K, Li, Mn, Na, Pb, Rb, Sn, Tl and Zn are present in the particulate phase, whereas the major portion of Hg is present in the gas phase. As, Br, Cd, Cl, I and Sb exist in a distribution between the gas phase and the particulate phase. Depending on the element, the precision of measurement ranges from 5 to 25% in terms of relative standard deviation of peak height and peak area, based on the fourth puff of 2R4F mainstream cigarette smoke analyzed in five smoking replicates

  6. Mass transfer in corrugated-plate membrane modules. I. Hyperfiltration experiments

    NARCIS (Netherlands)

    van der Waal, M.J.; Racz, I.G.

    1989-01-01

    The application of corrugations as turbulence promoters in membrane filtration was studied. This study showed that it is possible to deform an originally flat membrane to a corrugated shape without damaging it. In hyperfiltration experiments using corrugated cellulose acetate membranes it was found

  7. Mass transfer in corrugated-plate membrane modules. II. Ultrafiltration experiments

    NARCIS (Netherlands)

    van der Waal, M.J.; Stevanovic, S.; Racz, I.G.

    1989-01-01

    The application of corrugations as turbulence promoters in membrane filtration was studied. In ultrafiltration experiments with polysulfone membranes using Dextran T70 as solute, it was found that the corrugations result in reduced energy consumption or pressure drop compared with flat membranes at

  8. Dissolved atmospheric gas in xylem sap measured with membrane inlet mass spectrometry.

    Science.gov (United States)

    Schenk, H Jochen; Espino, Susana; Visser, Ate; Esser, Bradley K

    2016-04-01

    A new method is described for measuring dissolved gas concentrations in small volumes of xylem sap using membrane inlet mass spectrometry. The technique can be used to determine concentrations of atmospheric gases, such as argon, as reported here, or for any dissolved gases and their isotopes for a variety of applications, such as rapid detection of trace gases from groundwater only hours after they were taken up by trees and rooting depth estimation. Atmospheric gas content in xylem sap directly affects the conditions and mechanisms that allow for gas removal from xylem embolisms, because gas can dissolve into saturated or supersaturated sap only under gas pressure that is above atmospheric pressure. The method was tested for red trumpet vine, Distictis buccinatoria (Bignoniaceae), by measuring atmospheric gas concentrations in sap collected at times of minimum and maximum daily temperature and during temperature increase and decline. Mean argon concentration in xylem sap did not differ significantly from saturation levels for the temperature and pressure conditions at any time of collection, but more than 40% of all samples were supersaturated, especially during the warm parts of day. There was no significant diurnal pattern, due to high variability between samples. © 2015 John Wiley & Sons Ltd.

  9. Evaluation of the effect of reactant gases mass flow rates on power density in a polymer electrolyte membrane fuel cell

    Science.gov (United States)

    Kahveci, E. E.; Taymaz, I.

    2018-03-01

    In this study it was experimentally investigated the effect of mass flow rates of reactant gases which is one of the most important operational parameters of polymer electrolyte membrane (PEM) fuel cell on power density. The channel type is serpentine and single PEM fuel cell has an active area of 25 cm2. Design-Expert 8.0 (trial version) was used with four variables to investigate the effect of variables on the response using. Cell temperature, hydrogen mass flow rate, oxygen mass flow rate and humidification temperature were selected as independent variables. In addition, the power density was used as response to determine the combined effects of these variables. It was kept constant cell and humidification temperatures while changing mass flow rates of reactant gases. From the results an increase occurred in power density with increasing the hydrogen flow rates. But oxygen flow rate does not have a significant effect on power density within determined mass flow rates.

  10. Low molecular weight components in an aquatic humic substance as characterized by membrane dialysis and orbitrap mass spectrometry.

    Science.gov (United States)

    Remucal, Christina K; Cory, Rose M; Sander, Michael; McNeill, Kristopher

    2012-09-04

    Suwannee River fulvic acid (SRFA) was dialyzed through a 100-500 molecular weight cutoff dialysis membrane, and the dialysate and retentate were analyzed by UV-visible absorption and high-resolution Orbitrap mass spectrometry (MS). A significant fraction (36% based on dissolved organic carbon) of SRFA passed through the dialysis membrane. The fraction of SRFA in the dialysate had a different UV-visible absorption spectrum and was enriched in low molecular weight molecules with a more aliphatic composition relative to the initial SRFA solution. Comparison of the SRFA spectra collected by Orbitrap MS and Fourier transform ion cyclotron resonance MS (FT-ICR MS) demonstrated that the mass accuracy of the Orbitrap MS is sufficient for determination of unique molecular formulas of compounds with masses masses detected by Orbitrap MS were found in the 100-200 Da mass range. Many of these low molecular masses corresponded to molecular formulas of previously identified compounds in organic matter, lignin, and plants, and the use of the standard addition method provided an upper concentration estimate of selected target compounds in SRFA. Collectively, these results provide evidence that SRFA contains low molecular weight components that are present individually or in loosely bound assemblies.

  11. Inductively coupled plasma mass spectrometry with a twin quadrupole instrument using laser ablation sample introduction and monodisperse dried microparticulate injection

    Energy Technology Data Exchange (ETDEWEB)

    Allen, Lloyd A. [Iowa State Univ., Ames, IA (United States)

    1996-10-17

    The focus of this dissertation is the use of a twin quadrupole inductively coupled plasma mass spectrometer (ICP-MS) for the simultaneous detection of two m/z values. The twin quadrupole ICP-MS is used with laser ablation sample introduction in both the steady state (10 Hz) and single pulse modes. Steady state signals are highly correlated and the majority of flicker noise cancels when the ratio is calculated. Using a copper sample, the isotope ratio 63Cu+/65Cu+ is measured with a relative standard deviation (RSD) of 0.26%. Transient signals for single laser pulses are also obtained. Copper isotope ratio measurements for several laser pulses are measured with an RSD of 0.85%. Laser ablation (LA) is used with steel samples to assess the ability of the twin quadrupole ICP-MS to eliminate flicker noise of minor components of steel samples. Isotopic and internal standard ratios are measured in the first part of this work. The isotope ratio 52Cr+/53Cr+ (Cr present at 1.31 %) can be measured with an RSD of 0.06 % to 0.1 %. For internal standard elements, RSDs improve from 1.9 % in the Cr+ signal to 0.12% for the ratio of 51V+ to 52Cr+. In the second part of this work, one mass spectrometer is scanned while the second channel measures an individual m/z value. When the ratio of these two signals is calculated, the peak shapes in the mass spectrum are improved significantly. Pulses of analyte and matrix ions from individual drops are measured simultaneously using the twin quadrupole ICP-MS with monodisperse dried microparticulate injection (MDMI). At modest Pb concentrations (500 ppm), a shoulder on the leading edge of the Li+ signal becomes apparent. Space charge effects are consistent with the disturbances seen.

  12. Mass and Heat Transfer in Ion-Exchange Membranes Applicable to Solid Polymer Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Otteroey, M

    1996-04-01

    In this doctoral thesis, an improved emf method for determination of transference numbers of two counter ions in ion-exchange membranes is presented. Transference numbers were obtained as a continuous function of the composition. The method avoids problems with diffusion by using a stack of membranes. Water transference coefficients in ion-exchange membranes is discussed and reversible and irreversible water transfer is studied by emf methods. Efforts were made to get data relevant to the solid polymer fuel cell. The results support the findings of other researchers that the reversible water transfer is lower than earlier predicted. A chapter on the conductivity of ion-exchange membranes establishes a method to separate the very thin liquid layers surrounding the membranes in a stack. Using the method it was found that the conductivity is obtained with high accuracy and that the liquid layer in a membrane stack can contribute significantly to the total measured resistance. A four point impedance method was tested to measure the conductivity of membranes under fuel cell conditions. Finally, there is a discussion of reversible heat effects and heat transfer in ion-exchange membranes. 155 refs., 45 figs., 13 tabs.

  13. Mass transfer rate through liquid membranes: interfacial chemical reactions and diffusion as simultaneous permeability controlling factors

    International Nuclear Information System (INIS)

    Danesi, P.R.; Horwitz, E.P.; Vandegrift, G.F.; Chiarizia, R.

    1981-01-01

    Equations describing the permeability of a liquid membrane to metal cations have been derived taking into account aqueous diffusion, membrane diffusion, and interfacial chemical reactions as simultaneous permeability controlling factors. Diffusion and chemical reactions have been coupled by a simple model analogous to the one previously described by us to represent liquid-liquid extraction kinetics. The derived equations, which make use of experimentally determined interfacial reaction mechanisms, qualitatively fit unexplained literature data regarding Cu 2+ transfer through liquid membranes. Their use to predict and optimize membrane permeability in practical separation processes by setting the appropriate concentration of the membrane carrier [LIX 64 (General Mills), a commercial β-hydroxy-oxime] and the pH of the aqueous copper feed solution is briefly discussed. 4 figures

  14. Osmotic Power Generation by Inner Selective Hollow Fiber Membranes: An investigation of thermodynamics, mass transfer, and module scale modelling

    KAUST Repository

    Xiong, Jun Ying

    2016-12-29

    A comprehensive analysis of fluid motion, mass transport, thermodynamics and power generation during pressure retarded osmotic (PRO) processes was conducted. This work aims to (1) elucidate the fundamental relationship among various membrane properties and operation parameters and (2) analyse their individual and combined impacts on PRO module performance. A state-of-the-art inner-selective thin-film composite (TFC) hollow fiber membrane was employed in the modelling. The analyses of mass transfer and Gibbs free energy of mixing indicate that the asymmetric nature of hollow fibers results in more significant external concentration polarization (ECP) in the lumen side of the inner-selective hollow fiber membranes. In addition, a trade-off relationship exists between the power density (PD) and the specific energy (SE). The PD vs. SE trade-off upper bound may provide a useful guidance whether the flowrates of the feed and draw solutions should be further optimized in order to (1) minimize the boundary thickness and (2) maximize the osmotic power generation. Two new terms, mass transfer efficiency and power harvesting efficiency for osmotic power generation, have been proposed. This work may provide useful insights to design and operate PRO modules with enhanced performance so that the PRO process becomes more promising in real applications in the near future.

  15. Key factors regulating the mass delivery of macromolecules to model cell membranes

    DEFF Research Database (Denmark)

    Campbell, Richard A.; Watkins, Erik B.; Jagalski, Vivien

    2014-01-01

    We show that both gravity and electrostatics are key factors regulating interactions between model cell membranes and self-assembled liquid crystalline aggregates of dendrimers and phospholipids. The system is a proxy for the trafficking of reservoirs of therapeutic drugs to cell membranes for slow...... of the aggregates to activate endocytosis pathways on specific cell types is discussed in the context of targeted drug delivery applications....

  16. A one-step strategy for ultra-fast and low-cost mass production of plastic membrane microfluidic chips.

    Science.gov (United States)

    Hu, Chong; Lin, Sheng; Li, Wanbo; Sun, Han; Chen, Yangfan; Chan, Chiu-Wing; Leung, Chung-Hang; Ma, Dik-Lung; Wu, Hongkai; Ren, Kangning

    2016-10-05

    An ultra-fast, extremely cost-effective, and environmentally friendly method was developed for fabricating flexible microfluidic chips with plastic membranes. With this method, we could fabricate plastic microfluidic chips rapidly (within 12 seconds per piece) at an extremely low cost (less than $0.02 per piece). We used a heated perfluoropolymer perfluoroalkoxy (often called Teflon PFA) solid stamp to press a pile of two pieces of plastic membranes, low density polyethylene (LDPE) and polyethylene terephthalate (PET) coated with an ethylene-vinyl acetate copolymer (EVA). During the short period of contact with the heated PFA stamp, the pressed area of the membranes permanently bonded, while the LDPE membrane spontaneously rose up at the area not pressed, forming microchannels automatically. These two regions were clearly distinguishable even at the micrometer scale so we were able to fabricate microchannels with widths down to 50 microns. This method combines the two steps in the conventional strategy for microchannel fabrication, generating microchannels and sealing channels, into a single step. The production is a green process without using any solvent or generating any waste. Also, the chips showed good resistance against the absorption of Rhodamine 6G, oligonucleotides, and green fluorescent protein (GFP). We demonstrated some typical microfluidic manipulations with the flexible plastic membrane chips, including droplet formation, on-chip capillary electrophoresis, and peristaltic pumping for quantitative injection of samples and reagents. In addition, we demonstrated convenient on-chip detection of lead ions in water samples by a peristaltic-pumping design, as an example of the application of the plastic membrane chips in a resource-limited environment. Due to the high speed and low cost of the fabrication process, this single-step method will facilitate the mass production of microfluidic chips and commercialization of microfluidic technologies.

  17. Relative Abundance of Integral Plasma Membrane Proteins in Arabidopsis Leaf and Root Tissue Determined by Metabolic Labeling and Mass Spectrometry

    Science.gov (United States)

    Bernfur, Katja; Larsson, Olaf; Larsson, Christer; Gustavsson, Niklas

    2013-01-01

    Metabolic labeling of proteins with a stable isotope (15N) in intact Arabidopsis plants was used for accurate determination by mass spectrometry of differences in protein abundance between plasma membranes isolated from leaves and roots. In total, 703 proteins were identified, of which 188 were predicted to be integral membrane proteins. Major classes were transporters, receptors, proteins involved in membrane trafficking and cell wall-related proteins. Forty-one of the integral proteins, including nine of the 13 isoforms of the PIP (plasma membrane intrinsic protein) aquaporin subfamily, could be identified by peptides unique to these proteins, which made it possible to determine their relative abundance in leaf and root tissue. In addition, peptides shared between isoforms gave information on the proportions of these isoforms. A comparison between our data for protein levels and corresponding data for mRNA levels in the widely used database Genevestigator showed an agreement for only about two thirds of the proteins. By contrast, localization data available in the literature for 21 of the 41 proteins show a much better agreement with our data, in particular data based on immunostaining of proteins and GUS-staining of promoter activity. Thus, although mRNA levels may provide a useful approximation for protein levels, detection and quantification of isoform-specific peptides by proteomics should generate the most reliable data for the proteome. PMID:23990937

  18. Stimulation of Slack K+ channels alters mass at the plasma membrane by triggering dissociation of a phosphatase-regulatory complex

    Science.gov (United States)

    Fleming, Matthew R.; Brown, Maile R.; Kronengold, Jack; Zhang, Yalan; Jenkins, David P.; Barcia, Gulia; Nabbout, Rima; Bausch, Anne E.; Ruth, Peter; Lukowski, Robert; Navaratnam, Dhasakumar S.; Kaczmarek, Leonard K.

    2016-01-01

    Summary Human mutations in the cytoplasmic C-terminal domain of Slack sodium-activated potassium (KNa) channels result in childhood epilepsy with severe intellectual disability. Slack currents can be increased by pharmacological activators or by phosphorylation of a Slack C-terminal residue by protein kinase C. Using an optical biosensor assay, we find that Slack channel stimulation in neurons or transfected cells produces loss of mass near the plasma membrane. Slack mutants associated with intellectual disability fail to trigger any change in mass. The loss of mass results from the dissociation of the protein phosphatase 1 (PP1) targeting protein, Phactr-1, from the channel. Phactr1 dissociation is specific to wild-type Slack channels and is not observed when related potassium channels are stimulated. Our findings suggest that Slack channels are coupled to cytoplasmic signaling pathways, and that dysregulation of this coupling may trigger the aberrant intellectual development associated with specific childhood epilepsies. PMID:27545877

  19. Stimulation of Slack K+ Channels Alters Mass at the Plasma Membrane by Triggering Dissociation of a Phosphatase-Regulatory Complex

    Directory of Open Access Journals (Sweden)

    Matthew R. Fleming

    2016-08-01

    Full Text Available Human mutations in the cytoplasmic C-terminal domain of Slack sodium-activated potassium (KNa channels result in childhood epilepsy with severe intellectual disability. Slack currents can be increased by pharmacological activators or by phosphorylation of a Slack C-terminal residue by protein kinase C. Using an optical biosensor assay, we find that Slack channel stimulation in neurons or transfected cells produces loss of mass near the plasma membrane. Slack mutants associated with intellectual disability fail to trigger any change in mass. The loss of mass results from the dissociation of the protein phosphatase 1 (PP1 targeting protein, Phactr-1, from the channel. Phactr1 dissociation is specific to wild-type Slack channels and is not observed when related potassium channels are stimulated. Our findings suggest that Slack channels are coupled to cytoplasmic signaling pathways and that dysregulation of this coupling may trigger the aberrant intellectual development associated with specific childhood epilepsies.

  20. Damage to photosystem II due to heat stress without light-driven electron flow: involvement of enhanced introduction of reducing power into thylakoid membranes.

    Science.gov (United States)

    Marutani, Yoko; Yamauchi, Yasuo; Kimura, Yukihiro; Mizutani, Masaharu; Sugimoto, Yukihiro

    2012-08-01

    Under a moderately heat-stressed condition, the photosystems of higher plants are damaged in the dark more easily than they are in the presence of light. To obtain a better understanding of this heat-derived damage mechanism that occurs in the dark, we focused on the involvement of the light-independent electron flow that occurs at 40 °C during the damage. In various plant species, the maximal photochemical quantum yield of photosystem (PS) II (Fv/Fm) decreased as a result of heat treatment in the dark. In the case of wheat, the most sensitive plant species tested, both Fv/Fm and oxygen evolution rapidly decreased by heat treatment at 40 °C for 30 min in the dark. In the damage, specific degradation of D1 protein was involved, as shown by immunochemical analysis of major proteins in the photosystem. Because light canceled the damage to PSII, the light-driven electron flow may play a protective role against PSII damage without light. Light-independent incorporation of reducing power from stroma was enhanced at 40 °C but not below 35 °C. Arabidopsis mutants that have a deficit of enzymes which mediate the incorporation of stromal reducing power into thylakoid membranes were tolerant against heat treatment at 40 °C in the dark, suggesting that the reduction of the plastoquinone pool may be involved in the damage. In conclusion, the enhanced introduction of reducing power from stroma into thylakoid membranes that occurs around 40 °C causes over-reduction of plastoquinone, resulting in the damage to D1 protein under heat stress without linear electron flow.

  1. Maternal prepregnant body mass index, duration of breastfeeding, and timing of complementary food introduction are associated with infant weight gain

    DEFF Research Database (Denmark)

    Baker, Jennifer Lyn; Michaelsen, Kim F; Rasmussen, Kathleen M

    2004-01-01

    ). In this sample, prepregnant obesity (BMI > or = 30.0), short durations of breastfeeding, and earlier introduction of complementary food were associated with 0.7 kg of additional weight gain during infancy. CONCLUSIONS: Infant weight gain is associated with maternal prepregnant BMI and with an interaction between...... these associations among 3768 mother-infant dyads from the Danish National Birth Cohort. RESULTS: In multiple regression analyses, increasing maternal prepregnant BMI, decreasing durations of breastfeeding, and earlier complementary food introduction were associated with increased infant weight gain. An interaction...... was identified for short durations of breastfeeding (food introduction (associated with greater infant weight gain; however, the timing of complementary food introduction did not increase infant weight gain at longer durations of breastfeeding (> or =20 wk...

  2. Measurement of Membrane Characteristics Using the Phenomenological Equation and the Overall Mass Transport Equation in Ion-Exchange Membrane Electrodialysis of Saline Water

    Directory of Open Access Journals (Sweden)

    Yoshinobu Tanaka

    2012-01-01

    Full Text Available The overall membrane pair characteristics included in the overall mass transport equation are understandable using the phenomenological equations expressed in the irreversible thermodynamics. In this investigation, the overall membrane pair characteristics (overall transport number , overall solute permeability , overall electro-osmotic permeability and overall hydraulic permeability were measured by seawater electrodialysis changing current density, temperature and salt concentration, and it was found that occasionally takes minus value. For understanding the above phenomenon, new concept of the overall concentration reflection coefficient ∗ is introduced from the phenomenological equation. This is the aim of this investigation. ∗ is defined for describing the permselectivity between solutes and water molecules in the electrodialysis system just after an electric current interruption. ∗ is expressed by the function of and . ∗ is generally larger than 1 and is positive, but occasionally ∗ becomes less than 1 and becomes negative. Negative means that ions are transferred with water molecules (solvent from desalting cells toward concentrating cells just after an electric current interruption, indicating up-hill transport or coupled transport between water molecules and solutes.

  3. A Solution of the Convective-Diffusion Equation for Solute Mass Transfer inside a Capillary Membrane Bioreactor

    Directory of Open Access Journals (Sweden)

    B. Godongwana

    2010-01-01

    Full Text Available This paper presents an analytical model of substrate mass transfer through the lumen of a membrane bioreactor. The model is a solution of the convective-diffusion equation in two dimensions using a regular perturbation technique. The analysis accounts for radial-convective flow as well as axial diffusion of the substrate specie. The model is applicable to the different modes of operation of membrane bioreactor (MBR systems (e.g., dead-end, open-shell, or closed-shell mode, as well as the vertical or horizontal orientation. The first-order limit of the Michaelis-Menten equation for substrate consumption was used to test the developed model against available analytical results. The results obtained from the application of this model, along with a biofilm growth kinetic model, will be useful in the derivation of an efficiency expression for enzyme production in an MBR.

  4. Prostate cell membrane chromatography-liquid chromatography-mass spectrometry for screening of active constituents from Uncaria rhynchophylla.

    Science.gov (United States)

    He, Jianyu; Han, Shengli; Yang, Fangfang; Zhou, Nan; Wang, Sicen

    2013-01-01

    Uncaria rhynchophylla is a traditional Chinese medicinal herb used to treat hypertension and convulsive disorders such as epilepsy. Rat prostate cell membrane chromatography combined with liquid chromatography-mass spectrometry (LC-MS) was used to identify active constituents from U. rhynchophylla extracts. Four compounds (corynoxeine, isorhynchophylline, isocorynoxeine and rhynchophylline) were discovered. Competitive binding assay results indicated that the four compounds were in direct competition at a single common binding site and interacted with α1A adrenergic receptors (α1A-AR) in a manner similar to tamsulosin. Affinity constant values of the four compounds binding with α1A-AR were also measured using rat prostate cell membrane chromatography (CMC). Finally, their pharmacodynamic effects were tested on rat caudal arteries. This CMC combined LC-MS system offers a means of drug discovery by screening natural medicinal herbs for new pharmacologically active molecules targeting specific receptors.

  5. Modelling of cross-flow membrane contactors : Mass transfer with chemical reactions

    NARCIS (Netherlands)

    Dindore, V. Y.; Brilman, D. W. F.; Versteeg, G. F.

    2005-01-01

    Conventionally, carbon dioxide and hydrogen sulphide are absorbed using aqueous alkanolamines or carbonate solution in column type of equipment. However, in view of the unparallel advantages offered, the use of microporous hollow fiber membrane modules is an attractive alternative. In the present

  6. On-chip electro membrane extraction with online ultraviolet and mass spectrometric detection

    DEFF Research Database (Denmark)

    Petersen, Nickolaj Jacob; Foss, Sunniva Taule; Jensen, Henrik

    2011-01-01

    (SLM) consisted of 2-nitrophenyl octyl ether (NPOE) immobilized in the pores of the membrane. The driving force for the extraction was a 15 V direct current (DC) electrical potential applied across the SLM. Samples containing the basic drugs pethidine, nortriptyline, methadone, haloperidol, loperamide...

  7. Modelling of cross-flow membrane contactors : Physical mass transfer processes

    NARCIS (Netherlands)

    Dindore, V. Y.; Brilman, D. W. F.; Versteeg, G. F.

    2005-01-01

    Traditionally, hollow fiber membrane contactors used for gas-liquid contacting were designed in a shell and tube configuration with shell-side fluid flowing parallel to the fiber-side fluid, either in co-current or counter-current pattern. The primary limitations of these so-called 'parallel flow'

  8. Quantitative structure-retention relationship studies using immobilized artificial membrane chromatography I: amended linear solvation energy relationships with the introduction of a molecular electronic factor.

    Science.gov (United States)

    Li, Jie; Sun, Jin; Cui, Shengmiao; He, Zhonggui

    2006-11-03

    Linear solvation energy relationships (LSERs) amended by the introduction of a molecular electronic factor were employed to establish quantitative structure-retention relationships using immobilized artificial membrane (IAM) chromatography, in particular ionizable solutes. The chromatographic indices, log k(IAM), were determined by HPLC on an IAM.PC.DD2 column for 53 structurally diverse compounds, including neutral, acidic and basic compounds. Unlike neutral compounds, the IAM chromatographic retention of ionizable compounds was affected by their molecular charge state. When the mean net charge per molecule (delta) was introduced into the amended LSER as the sixth variable, the LSER regression coefficient was significantly improved for the test set including ionizable solutes. The delta coefficients of acidic and basic compounds were quite different indicating that the molecular electronic factor had a markedly different impact on the retention of acidic and basic compounds on IAM column. Ionization of acidic compounds containing a carboxylic group tended to impair their retention on IAM, while the ionization of basic compounds did not have such a marked effect. In addition, the extra-interaction with the polar head of phospholipids might cause a certain change in the retention of basic compounds. A comparison of calculated and experimental retention indices suggested that the semi-empirical LSER amended by the addition of a molecular electronic factor was able to reproduce adequately the experimental retention factors of the structurally diverse solutes investigated.

  9. Molecularly imprinted polymer (MIP) membrane assisted direct spray ionization mass spectrometry for agrochemicals screening in foodstuffs.

    Science.gov (United States)

    Pereira, Igor; Rodrigues, Marcella Ferreira; Chaves, Andréa Rodrigues; Vaz, Boniek Gontijo

    2018-02-01

    Paper spray ionization (PSI) has some limitations such as low sensitivity and ionization suppression when complex samples are analyzed. The use of sample preparation devices directly coupled to MS can avoid these restrictions. Molecularly imprinted polymers (MIPs) are materials widely used as adsorbent in sample preparation methods such as solid-phase extraction and solid-phase microextraction, and they can provide specifics cavities with affinity to a target molecule. Here, we introduce a new MIP membrane spray ionization method combining MIP and PSI. MIP was synthesized directly on a cellulose membrane. Monuron and 2,4,5-T (2,4,5-trichlorophenoxyacetic acid) were used as template molecules in MIP synthesis for diuron and 2,4-D (2,4-dichlorophenoxyacetic acid) analyte sequesters, respectively. Apple, banana and grape methanolic extracts were used as matrices. The MIP membrane spray showed signal intensities of diuron and 2,4-D that were much higher compared to those obtained by non-imprinted polymers(NIP). Calibration curves exhibited R 2 > 0.99 for diuron and 2,4-D in all fruit extracts analyzed. LODs were found less than 0.60µgL -1 and LLOQs were found less than 2.00µgL -1 . The coefficients of variation and relative errors were less than 15% for almost all analyses. The apparent recovery test results ranged between 92,5% and 116.9%. Finally, the MIP membrane spray method was employed for the quantification of diuron and 2,4-D in real samples. Diuron contents were only found in three bananas (4.0, 6.5, and 9.9µgL -1 ). The proposed MIP membrane spray ionization method was straightforward, fast to carry out and provided satisfactory results for analyses of diuron and 2,4-D in apple, banana and grape samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Mass-charge-heat coupled transfers in a single cell of a proton exchange membrane fuel cell; Transferts couples masse-charge-chaleur dans une cellule de pile a combustible a membrane polymere

    Energy Technology Data Exchange (ETDEWEB)

    Ramousse, J

    2005-11-15

    Understanding and modelling of coupled mass, charges and heat transfers phenomena are fundamental to analyze the electrical behaviour of the system. The aim of the present model is to describe electrical performances of a PEFMC according to the fluidic and thermal operating conditions. The water content of the membrane and the water distribution in the single cell are estimated according to the coupled simulations of mass transport in the thickness of the single cell and in the feeding channels of the bipolar plates. A microscopic model of a Gas Diffusion Electrode is built up to describe charges transfer phenomena occurring at the electrodes. Completed by a study of heat transfer in the Membrane Electrode Assembly, conditions and preferential sites of water vapor condensation can be highlighted. A set of measurements of the effective thermal conductivity of carbon felts used in fuel cells as porous backing layers have also been performed. Although the value of this parameter is essential for the study of heat transfer, it is still under investigation because of the strong thermal anisotropy of the medium. (author)

  11. A comparison of mass transfer coefficients between trickle-bed, hollow fiber membrane and stirred tank reactors.

    Science.gov (United States)

    Orgill, James J; Atiyeh, Hasan K; Devarapalli, Mamatha; Phillips, John R; Lewis, Randy S; Huhnke, Raymond L

    2013-04-01

    Trickle-bed reactor (TBR), hollow fiber membrane reactor (HFR) and stirred tank reactor (STR) can be used in fermentation of sparingly soluble gasses such as CO and H2 to produce biofuels and bio-based chemicals. Gas fermenting reactors must provide high mass transfer capabilities that match the kinetic requirements of the microorganisms used. The present study compared the volumetric mass transfer coefficient (K(tot)A/V(L)) of three reactor types; the TBR with 3 mm and 6 mm beads, five different modules of HFRs, and the STR. The analysis was performed using O2 as the gaseous mass transfer agent. The non-porous polydimethylsiloxane (PDMS) HFR provided the highest K(tot)A/V(L) (1062 h(-1)), followed by the TBR with 6mm beads (421 h(-1)), and then the STR (114 h(-1)). The mass transfer characteristics in each reactor were affected by agitation speed, and gas and liquid flow rates. Furthermore, issues regarding the comparison of mass transfer coefficients are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Assessing the Mitochondrial Membrane Potential in Cells and In Vivo using Targeted Click Chemistry and Mass Spectrometry.

    Science.gov (United States)

    Logan, Angela; Pell, Victoria R; Shaffer, Karl J; Evans, Cameron; Stanley, Nathan J; Robb, Ellen L; Prime, Tracy A; Chouchani, Edward T; Cochemé, Helena M; Fearnley, Ian M; Vidoni, Sara; James, Andrew M; Porteous, Carolyn M; Partridge, Linda; Krieg, Thomas; Smith, Robin A J; Murphy, Michael P

    2016-02-09

    The mitochondrial membrane potential (Δψm) is a major determinant and indicator of cell fate, but it is not possible to assess small changes in Δψm within cells or in vivo. To overcome this, we developed an approach that utilizes two mitochondria-targeted probes each containing a triphenylphosphonium (TPP) lipophilic cation that drives their accumulation in response to Δψm and the plasma membrane potential (Δψp). One probe contains an azido moiety and the other a cyclooctyne, which react together in a concentration-dependent manner by "click" chemistry to form MitoClick. As the mitochondrial accumulation of both probes depends exponentially on Δψm and Δψp, the rate of MitoClick formation is exquisitely sensitive to small changes in these potentials. MitoClick accumulation can then be quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). This approach enables assessment of subtle changes in membrane potentials within cells and in the mouse heart in vivo. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  13. One dimensional transient numerical study of the mass heat and charge transfer in a proton exchange membrane for PEMFC

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, Djamel; Benmoussa, Hocine [Laboratory (LESEI), Faculty of Engineering, University of Batna (Algeria); Bourmada, Noureddine; Oulmi, Kafia [Laboratory LCCE, Faculty of Science, University of Batna (Algeria); Mahmah, Bouziane; Belhamel, Maiouf [CDER, BP, 62 Avenue-Observatoire, Bouzareah, Alger (Algeria)

    2009-06-15

    The objective of our study is to quantify the mass water transferred by various modes: diffusion, convection and migration. For the water transfer, the principal forces considered in the model are, the convection force, the osmotic force (i.e. diffusion) and the electric force (migration). The first of these forces results from a pressure gradient, the second of a concentration gradient and the third of a protons' migration from the anode to the cathode, which has an effect on the dipole of the water molecules (resistance force to the advancement). The numerical tool used to solve the equations' system is the finite element method. The results obtained numerically considering this method are concentration profiles and concentration variation with time and membrane thickness. These results illustrate the contribution of each mass transfer mode. (author)

  14. A membrane inlet mass spectrometry system for noble gases at natural abundances in gas and water samples.

    Science.gov (United States)

    Visser, Ate; Singleton, Michael J; Hillegonds, Darren J; Velsko, Carol A; Moran, Jean E; Esser, Bradley K

    2013-11-15

    Noble gases dissolved in groundwater can reveal paleotemperatures, recharge conditions, and precise travel times. The collection and analysis of noble gas samples are cumbersome, involving noble gas purification, cryogenic separation and static mass spectrometry. A quicker and more efficient sample analysis method is required for introduced tracer studies and laboratory experiments. A Noble Gas Membrane Inlet Mass Spectrometry (NG-MIMS) system was developed to measure noble gases at natural abundances in gas and water samples. The NG-MIMS system consists of a membrane inlet, a dry-ice water trap, a carbon-dioxide trap, two getters, a gate valve, a turbomolecular pump and a quadrupole mass spectrometer equipped with an electron multiplier. Noble gases isotopes (4)He, (22)Ne, (38)Ar, (84)Kr and (132)Xe are measured every 10 s. The NG-MIMS system can reproduce measurements made on a traditional noble gas mass spectrometer system with precisions of 2%, 8%, 1%, 1% and 3% for He, Ne, Ar, Kr and Xe, respectively. Noble gas concentrations measured in an artificial recharge pond were used to monitor an introduced xenon tracer and to reconstruct temperature variations to within 2 °C. Additional experiments demonstrated the capability to measure noble gases in gas and in water samples, in real time. The NG-MIMS system is capable of providing analyses sufficiently accurate and precise for introduced noble gas tracers at managed aquifer recharge facilities, groundwater fingerprinting based on excess air and noble gas recharge temperature, and field and laboratory studies investigating ebullition and diffusive exchange. Copyright © 2013 John Wiley & Sons, Ltd.

  15. Correlation of the Rock Mass Rating (RMR) System with the Unified Soil Classification System (USCS): Introduction of the Weak Rock Mass Rating System (W-RMR)

    Science.gov (United States)

    Warren, Sean N.; Kallu, Raj R.; Barnard, Chase K.

    2016-11-01

    Underground gold mines in Nevada are exploiting increasingly deeper ore bodies comprised of weak to very weak rock masses. The Rock Mass Rating (RMR) classification system is widely used at underground gold mines in Nevada and is applicable in fair to good-quality rock masses, but is difficult to apply and loses reliability in very weak rock mass to soil-like material. Because very weak rock masses are transition materials that border engineering rock mass and soil classification systems, soil classification may sometimes be easier and more appropriate to provide insight into material behavior and properties. The Unified Soil Classification System (USCS) is the most likely choice for the classification of very weak rock mass to soil-like material because of its accepted use in tunnel engineering projects and its ability to predict soil-like material behavior underground. A correlation between the RMR and USCS systems was developed by comparing underground geotechnical RMR mapping to laboratory testing of bulk samples from the same locations, thereby assigning a numeric RMR value to the USCS classification that can be used in spreadsheet calculations and geostatistical analyses. The geotechnical classification system presented in this paper including a USCS-RMR correlation, RMR rating equations, and the Geo-Pick Strike Index is collectively introduced as the Weak Rock Mass Rating System (W-RMR). It is the authors' hope that this system will aid in the classification of weak rock masses and more usable design tools based on the RMR system. More broadly, the RMR-USCS correlation and the W-RMR system help define the transition between engineering soil and rock mass classification systems and may provide insight for geotechnical design in very weak rock masses.

  16. Quantitative real-time monitoring of multi-elements in airborne particulates by direct introduction into an inductively coupled plasma mass spectrometer

    International Nuclear Information System (INIS)

    Suzuki, Yoshinari; Sato, Hikaru; Hiyoshi, Katsuhiro; Furuta, Naoki

    2012-01-01

    A new calibration system for real-time determination of trace elements in airborne particulates was developed. Airborne particulates were directly introduced into an inductively coupled plasma mass spectrometer, and the concentrations of 15 trace elements were determined by means of an external calibration method. External standard solutions were nebulized by an ultrasonic nebulizer (USN) coupled with a desolvation system, and the resulting aerosol was introduced into the plasma. The efficiency of sample introduction via the USN was calculated by two methods: (1) the introduction of a Cr standard solution via the USN was compared with introduction of a Cr(CO) 6 standard gas via a standard gas generator and (2) the aerosol generated by the USN was trapped on filters and then analyzed. The Cr introduction efficiencies obtained by the two methods were the same, and the introduction efficiencies of the other elements were equal to the introduction efficiency of Cr. Our results indicated that our calibration method for introduction efficiency worked well for the 15 elements (Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Mo, Sn, Sb, Ba, Tl and Pb). The real-time data and the filter-collection data agreed well for elements with low-melting oxides (V, Co, As, Mo, Sb, Tl, and Pb). In contrast, the real-time data were smaller than the filter-collection data for elements with high-melting oxides (Ti, Cr, Mn, Ni, Cu, Zn, Sn, and Ba). This result implies that the oxides of these 8 elements were not completely fused, vaporized, atomized, and ionized in the initial radiation zone of the inductively coupled plasma. However, quantitative real-time monitoring can be realized after correction for the element recoveries which can be calculated from the ratio of real-time data/filter-collection data. - Highlights: ► APs were directly introduced into ICP-MS and real-time analysis was performed. ► The real-time data were calibrated by a multi-element standard solution from USN. ► During real

  17. Nanodisc-based Co-immunoprecipitation for Mass Spectrometric Identification of Membrane-interacting Proteins

    DEFF Research Database (Denmark)

    Borch-Jensen, Jonas; Roepstorff, Peter; Møller-Jensen, Jakob

    2011-01-01

    enterotoxigenic Escherischia coli, GM1-nanodiscs were employed for co-immunoprecipitation. The B subunit of heat labile enterotoxin was identified as a specific interaction partner by mass spectrometry, thus demonstrating that nanodisc technology is useful for highly specific detection and identification...

  18. Influence of Capillary Condensation Effects on Mass Transport through Porous Membranes

    Czech Academy of Sciences Publication Activity Database

    Uchytil, Petr; Petričkovič, Roman; Thomas, S.; Siedel-Morgenstern, A.

    2003-01-01

    Roč. 33, č. 3 (2003), s. 273-281 ISSN 1383-5866 R&D Projects: GA ČR GA104/01/0945 Institutional research plan: CEZ:AV0Z4072921 Keywords : capillary condensation * mass transport * gas separation Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.355, year: 2003

  19. Mass transfer simulation of nanofiltration membranes for electrolyte solutions through generalized Maxwell-Stefan approach

    International Nuclear Information System (INIS)

    Hoshyargar, Vahid; Fadaei, Farzad; Ashrafizadeh, Seyed Nezameddin

    2015-01-01

    A comprehensive mathematical model is developed for simulation of ion transport through nanofiltration membranes. The model is based on the Maxwell-Stefan approach and takes into account steric, Donnan, and dielectric effects in the transport of mono and divalent ions. Theoretical ion rejection for multi-electrolyte mixtures was obtained by numerically solving the 'hindered transport' based on the generalized Maxwell-Stefan equation for the flux of ions. A computer simulation has been developed to predict the transport in the range of nanofiltration, a numerical procedure developed linearization and discretization form of the governing equations, and the finite volume method was employed for the numerical solution of equations. The developed numerical method is capable of solving equations for multicomponent systems of n species no matter to what extent the system shows stiffness. The model findings were compared and verified with the experimental data from literature for two systems of Na 2 SO 4 +NaCl and MgCl 2 +NaCl. Comparison showed great agreement for different concentrations. As such, the model is capable of predicting the rejection of different ions at various concentrations. The advantage of such a model is saving costs as a result of minimizing the number of required experiments, while it is closer to a realistic situation since the adsorption of ions has been taken into account. Using this model, the flux of permeates and rejections of multi-component liquid feeds can be calculated as a function of membrane properties. This simulation tool attempts to fill in the gap in methods used for predicting nanofiltration and optimization of the performance of charged nanofilters through generalized Maxwell-Stefan (GMS) approach. The application of the current model may weaken the latter gap, which has arisen due to the complexity of the fundamentals of ion transport processes via this approach, and may further facilitate the industrial development of

  20. Label-free quantitative mass spectrometry for analysis of protein antigens in a meningococcal group B outer membrane vesicle vaccine.

    Science.gov (United States)

    Dick, Lawrence W; Mehl, John T; Loughney, John W; Mach, Anna; Rustandi, Richard R; Ha, Sha; Zhang, Lan; Przysiecki, Craig T; Dieter, Lance; Hoang, Van M

    2015-01-01

    The development of a multivalent outer membrane vesicle (OMV) vaccine where each strain contributes multiple key protein antigens presents numerous analytical challenges. One major difficulty is the ability to accurately and specifically quantitate each antigen, especially during early development and process optimization when immunoreagents are limited or unavailable. To overcome this problem, quantitative mass spectrometry methods can be used. In place of traditional mass assays such as enzyme-linked immunosorbent assays (ELISAs), quantitative LC-MS/MS using multiple reaction monitoring (MRM) can be used during early-phase process development to measure key protein components in complex vaccines in the absence of specific immunoreagents. Multiplexed, label-free quantitative mass spectrometry methods using protein extraction by either detergent or 2-phase solvent were developed to quantitate levels of several meningococcal serogroup B protein antigens in an OMV vaccine candidate. Precision was demonstrated to be less than 15% RSD for the 2-phase extraction and less than 10% RSD for the detergent extraction method. Accuracy was 70 to 130% for the method using a 2-phase extraction and 90-110% for detergent extraction. The viability of MS-based protein quantification as a vaccine characterization method was demonstrated and advantages over traditional quantitative methods were evaluated. Implementation of these MS-based quantification methods can help to decrease the development time for complex vaccines and can provide orthogonal confirmation of results from existing antigen quantification techniques.

  1. Stimulation of Slack K(+) Channels Alters Mass at the Plasma Membrane by Triggering Dissociation of a Phosphatase-Regulatory Complex.

    Science.gov (United States)

    Fleming, Matthew R; Brown, Maile R; Kronengold, Jack; Zhang, Yalan; Jenkins, David P; Barcia, Gulia; Nabbout, Rima; Bausch, Anne E; Ruth, Peter; Lukowski, Robert; Navaratnam, Dhasakumar S; Kaczmarek, Leonard K

    2016-08-30

    Human mutations in the cytoplasmic C-terminal domain of Slack sodium-activated potassium (KNa) channels result in childhood epilepsy with severe intellectual disability. Slack currents can be increased by pharmacological activators or by phosphorylation of a Slack C-terminal residue by protein kinase C. Using an optical biosensor assay, we find that Slack channel stimulation in neurons or transfected cells produces loss of mass near the plasma membrane. Slack mutants associated with intellectual disability fail to trigger any change in mass. The loss of mass results from the dissociation of the protein phosphatase 1 (PP1) targeting protein, Phactr-1, from the channel. Phactr1 dissociation is specific to wild-type Slack channels and is not observed when related potassium channels are stimulated. Our findings suggest that Slack channels are coupled to cytoplasmic signaling pathways and that dysregulation of this coupling may trigger the aberrant intellectual development associated with specific childhood epilepsies. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Quantifying Contribution of Synthrophic Acetate Oxidation to Methane Production in Thermophilic Anaerobic Reactors by Membrane Inlet Mass Spectrometry

    DEFF Research Database (Denmark)

    Mulat, Daniel Girma; Ward, Alastair James; Adamsen, Anders Peter S.

    2014-01-01

    A unique method was developed and applied for monitoring methanogenesis pathways based on isotope labeled substrates combined with online membrane inlet quadrupole mass spectrometry (MIMS). In our study, a fermentation sample from a full-scale biogas plant fed with pig and cattle manure, maize...... silage, and deep litter was incubated with 100 mM of [2-13C] sodium acetate under thermophilic anaerobic conditions. MIMS was used to measure the isotopic distribution of dissolved CO2 and CH4 during the degradation of acetate, while excluding interference from water by applying a cold trap. After 6 days...... a new approach for online quantification of the relative contribution of methanogenesis pathways to methane production with a time resolution shorter than one minute. The observed contribution of SAO-HM to methane production under the tested conditions challenges the current widely accepted anaerobic...

  3. An introduction to the technique of combined ion mobility spectrometry-mass spectrometry for the analysis of complex biological samples

    International Nuclear Information System (INIS)

    McDowall, Mark A.; Bateman, Robert H.; Bajic, Steve; Giles, Kevin; Langridge, Jim; McKenna, Therese; Pringle, Steven D.; Wildgoose, Jason L.

    2008-01-01

    Full Text: Ultra Performance Liquid Chromatography (UPLC) offers several advantages compared with conventional High Performance Liquid Chromatography (HPLC) as an 'inlet system' for mass spectrometry. UPLC provides improved chromatographic resolution, increased sensitivity and reduced analysis time. This is achieved through the use of sub 2μm particles (stationary phase) combined with high-pressure solvent delivery (up to 15,000 psi). When coupled with orthogonal acceleration time-of-flight (oa-TOF) mass spectrometry (MS), UPLC presents a means to achieve high sample throughput with reduced spectral overlap, increased sensitivity, and exact mass measurement capabilities with high mass spectral resolution (Ca 20,000 FWHM). Dispersive ion mobility spectrometry (IMS) implemented within a traveling-wave ion guide provides an orthogonal separation strategy for ions in the gas phase that can resolve isobaric ions formed by either Electrospray of MALDI ionization typically in Ca 20 mille seconds. All three techniques have the potential to be combined on-line (e.g. UPLC-IMS-MS/MS) in real time to maximize peak capacity and resolving power for the analysis of complex biological mixtures including; intact proteins, modified peptides and endogenous/exogenous metabolites

  4. Mass transfer modeling on the separation of tantalum and niobium from dilute hydrofluoric media through a hollow fiber supported liquid membrane

    International Nuclear Information System (INIS)

    Buachuang, Duenphen; Ramakul, Prakorn; Leepipatpiboon, Natchanun; Pancharoen, Ura

    2011-01-01

    Highlights: → Simultaneous separation of tantalum and niobium from the mixture solution. → An extraction through a hollow fiber supported liquid membrane (HFSLM). → The effect on tantalum removal found from Aliquat 336. → The mathematical model focusing on the extraction side of the liquid membrane system was presented. → The mass transfer coefficients of the aqueous feed (k i ) and the organic membrane phase (k m ) for the system were estimated as 1.19 x 10 -5 and 1.39 x 10 -7 cm/s, respectively. → Experimental data and theoretical values were found to be in good agreement when the concentration of Aliquat336 in the membrane phase was below 4% (v/v). - Abstract: The separation of a mixture of tantalum and niobium in dilute hydrofluoric media via hollow fiber supported liquid membrane (HFSLM) was examined. Quaternary ammonium salt (Aliquat336) diluted in kerosene was used as a carrier. The various effects on the transport and separation of tantalum and niobium were studied: concentration of hydrofluoric acid in the feed solution, concentration of the carrier (Aliquat336) in the membrane phase, types of stripping solutions (NaClO 4 , thiourea and HCl) and their concentration. The extraction of tantalum in the membrane phase from 0.3 M hydrofluoric acid (HF) by 3% (v/v) Aliquat336 was achieved by leaving niobium in the feed solution. Quantitative recovery of tantalum was achieved by 0.2 M NaClO 4 . Furthermore, a mathematical model focusing on the extraction side of the liquid membrane system was presented in order to predict the concentration of tantalum at different times. The mass transfer coefficients of the aqueous feed (k i ) and the organic membrane phase (k m ) were estimated as 1.19 x 10 -5 and 1.39 x 10 -7 cm/s, respectively. Therefore, the mass transfer limiting step is the diffusion of tantalum-Aliquat336 through the liquid membrane. Moreover, mass transfer modeling was performed and the validity of the developed model evaluated. Experimental

  5. Mass transfer modeling on the separation of tantalum and niobium from dilute hydrofluoric media through a hollow fiber supported liquid membrane

    Energy Technology Data Exchange (ETDEWEB)

    Buachuang, Duenphen [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330 (Thailand); Ramakul, Prakorn [Department of Chemical Engineering, Faculty of Engineering and Industrial Technology, Silpakorn University, Nakhon Pathom 73000 (Thailand); Leepipatpiboon, Natchanun [Chromatography and Separation Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Patumwan, Bangkok 10330 (Thailand); Pancharoen, Ura, E-mail: ura.p.@chula.ac.th [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330 (Thailand)

    2011-09-29

    Highlights: > Simultaneous separation of tantalum and niobium from the mixture solution. > An extraction through a hollow fiber supported liquid membrane (HFSLM). > The effect on tantalum removal found from Aliquat 336. > The mathematical model focusing on the extraction side of the liquid membrane system was presented. > The mass transfer coefficients of the aqueous feed (k{sub i}) and the organic membrane phase (k{sub m}) for the system were estimated as 1.19 x 10{sup -5} and 1.39 x 10{sup -7} cm/s, respectively. > Experimental data and theoretical values were found to be in good agreement when the concentration of Aliquat336 in the membrane phase was below 4% (v/v). - Abstract: The separation of a mixture of tantalum and niobium in dilute hydrofluoric media via hollow fiber supported liquid membrane (HFSLM) was examined. Quaternary ammonium salt (Aliquat336) diluted in kerosene was used as a carrier. The various effects on the transport and separation of tantalum and niobium were studied: concentration of hydrofluoric acid in the feed solution, concentration of the carrier (Aliquat336) in the membrane phase, types of stripping solutions (NaClO{sub 4}, thiourea and HCl) and their concentration. The extraction of tantalum in the membrane phase from 0.3 M hydrofluoric acid (HF) by 3% (v/v) Aliquat336 was achieved by leaving niobium in the feed solution. Quantitative recovery of tantalum was achieved by 0.2 M NaClO{sub 4}. Furthermore, a mathematical model focusing on the extraction side of the liquid membrane system was presented in order to predict the concentration of tantalum at different times. The mass transfer coefficients of the aqueous feed (k{sub i}) and the organic membrane phase (k{sub m}) were estimated as 1.19 x 10{sup -5} and 1.39 x 10{sup -7} cm/s, respectively. Therefore, the mass transfer limiting step is the diffusion of tantalum-Aliquat336 through the liquid membrane. Moreover, mass transfer modeling was performed and the validity of the

  6. General introduction to glucosinolates

    DEFF Research Database (Denmark)

    Halkier, Barbara Ann

    2016-01-01

    will be presented a general introduction to glucosinolates ranging from the evolution of glucosinolates to the many roles glucosinolates have for humans as well as an overview of the current knowledge on the orchestration of the glucosinolate biosynthetic pathway. The latter includes an introduction to the genes...... to the plasma membrane. Examples of how the knowledge gained from basic research has been translated into applied glucosinolate research through pathway and transport engineering will be presented....

  7. Mass Spectrometry Method to Measure Membrane Proteins in Dried Blood Spots for the Detection of Blood Doping Practices in Sport.

    Science.gov (United States)

    Cox, Holly D; Eichner, Daniel

    2017-09-19

    The dried blood spot (DBS) matrix has significant utility for applications in the field where venous blood collection and timely shipment of labile blood samples is difficult. Unfortunately, protein measurement in DBS is hindered by high abundance proteins and matrix interference that increases with hematocrit. We developed a DBS method to enrich for membrane proteins and remove soluble proteins and matrix interference. Following a wash in a series of buffers, the membrane proteins are digested with trypsin and quantitated by parallel reaction monitoring mass spectrometry methods. The DBS method was applied to the quantification of four cell-specific cluster of differentiation (CD) proteins used to count cells by flow cytometry, band 3 (CD233), CD71, CD45, and CD41. We demonstrate that the DBS method counts low abundance cell types such as immature reticulocytes as well as high abundance cell types such as red blood cells, white blood cells, and platelets. When tested in 82 individuals, counts obtained by the DBS method demonstrated good agreement with flow cytometry and automated hematology analyzers. Importantly, the method allows longitudinal monitoring of CD protein concentration and calculation of interindividual variation which is difficult by other methods. Interindividual variation of band 3 and CD45 was low, 6 and 8%, respectively, while variation of CD41 and CD71 was higher, 18 and 78%, respectively. Longitudinal measurement of CD71 concentration in DBS over an 8-week period demonstrated intraindividual variation 17.1-38.7%. Thus, the method may allow stable longitudinal measurement of blood parameters currently monitored to detect blood doping practices.

  8. Sensitive and comprehensive detection of chemical warfare agents in air by atmospheric pressure chemical ionization ion trap tandem mass spectrometry with counterflow introduction.

    Science.gov (United States)

    Seto, Yasuo; Sekiguchi, Hiroshi; Maruko, Hisashi; Yamashiro, Shigeharu; Sano, Yasuhiro; Takayama, Yasuo; Sekioka, Ryoji; Yamaguchi, Shintaro; Kishi, Shintaro; Satoh, Takafumi; Sekiguchi, Hiroyuki; Iura, Kazumitsu; Nagashima, Hisayuki; Nagoya, Tomoki; Tsuge, Kouichiro; Ohsawa, Isaac; Okumura, Akihiko; Takada, Yasuaki; Ezawa, Naoya; Watanabe, Susumu; Hashimoto, Hiroaki

    2014-05-06

    A highly sensitive and specific real-time field-deployable detection technology, based on counterflow air introduction atmospheric pressure chemical ionization, has been developed for a wide range of chemical warfare agents (CWAs) comprising gaseous (two blood agents, three choking agents), volatile (six nerve gases and one precursor agent, five blister agents), and nonvolatile (three lachrymators, three vomiting agents) agents in air. The approach can afford effective chemical ionization, in both positive and negative ion modes, for ion trap multiple-stage mass spectrometry (MS(n)). The volatile and nonvolatile CWAs tested provided characteristic ions, which were fragmented into MS(3) product ions in positive and negative ion modes. Portions of the fragment ions were assigned by laboratory hybrid mass spectrometry (MS) composed of linear ion trap and high-resolution mass spectrometers. Gaseous agents were detected by MS or MS(2) in negative ion mode. The limits of detection for a 1 s measurement were typically at or below the microgram per cubic meter level except for chloropicrin (submilligram per cubic meter). Matrix effects by gasoline vapor resulted in minimal false-positive signals for all the CWAs and some signal suppression in the case of mustard gas. The moisture level did influence the measurement of the CWAs.

  9. Introduction to Body Composition Assessment Using the Deuterium Dilution Technique with Analysis of Urine Samples by Isotope Ratio Mass Spectrometry

    International Nuclear Information System (INIS)

    2010-01-01

    The IAEA has fostered the more widespread use of a stable isotope technique to assess body composition in different population groups to address priority areas in public health nutrition in Member States. It has done this by supporting national and regional nutrition projects through its technical cooperation programme and coordinated research projects over many years. This publication was developed by an international group of experts to provide practical hands-on guidance in the use of this technique in settings where analysis of stable isotope ratios in biological samples is to be made by isotope ratio mass spectrometry. The publication is targeted at new users of this technique, for example nutritionists, analytical chemists and other professionals. More detailed information on the theoretical background and the practical applications of state of the art methodologies to monitor changes in body composition can be found in IAEA Human Health Series No. 3, Assessment of Body Composition and Total Energy Expenditure in Humans by Stable Isotope Techniques

  10. Mass

    International Nuclear Information System (INIS)

    Quigg, Chris

    2007-01-01

    In the classical physics we inherited from Isaac Newton, mass does not arise, it simply is. The mass of a classical object is the sum of the masses of its parts. Albert Einstein showed that the mass of a body is a measure of its energy content, inviting us to consider the origins of mass. The protons we accelerate at Fermilab are prime examples of Einsteinian matter: nearly all of their mass arises from stored energy. Missing mass led to the discovery of the noble gases, and a new form of missing mass leads us to the notion of dark matter. Starting with a brief guided tour of the meanings of mass, the colloquium will explore the multiple origins of mass. We will see how far we have come toward understanding mass, and survey the issues that guide our research today.

  11. Syngas fermentation to biofuel: evaluation of carbon monoxide mass transfer and analytical modeling using a composite hollow fiber (CHF) membrane bioreactor.

    Science.gov (United States)

    Munasinghe, Pradeep Chaminda; Khanal, Samir Kumar

    2012-10-01

    In this study, the volumetric mass transfer coefficients (Ka) for CO were examined in a composite hollow fiber (CHF) membrane bioreactor. The mass transfer experiments were conducted at various inlet gas pressures (from 5 to 30 psig (34.5-206.8 kPa(g))) and recirculation flow rates (300, 600, 900, 1200 and 1500 mL/min) through CHF module. The highest Ka value of 946.6 1/h was observed at a recirculation rate of 1500 mL/min and at an inlet gas pressure of 30 psig(206.8 kPa(g)). The findings of this study confirm that the use of CHF membranes is effective and improves the efficiency CO mass transfer into the aqueous phase. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: A tutorial review. Part II. Practical considerations

    International Nuclear Information System (INIS)

    Leclercq, Amélie; Nonell, Anthony; Todolí Torró, José Luis; Bresson, Carole; Vio, Laurent; Vercouter, Thomas; Chartier, Frédéric

    2015-01-01

    Graphical abstract: This tutorial review is dedicated to the analysis of organic/hydro-organic matrices by ICP techniques. A state-of-the-art focusing on sample introduction, relevant operating parameters optimization and analytical strategies for elemental quantification is provided. - Highlights: • Practical considerations to perform analyses in organic/hydro-organic matrices. • Description, benefits and drawbacks of recent introduction devices. • Optimization to improve plasma tolerance towards organic/hydro-organic matrices. • Analytical strategies for elemental quantification in organic/hydro-organic matrices. - Abstract: Inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are increasingly used to carry out analyses in organic/hydro-organic matrices. The introduction of such matrices into ICP sources is particularly challenging and can be the cause of numerous drawbacks. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP sources. Part I provided theoretical considerations associated with the physico-chemical properties of such matrices, in an attempt to understand the induced phenomena. Part II of this tutorial review is dedicated to more practical considerations on instrumentation, instrumental and operating parameters, as well as analytical strategies for elemental quantification in such matrices. Two important issues are addressed in this part: the first concerns the instrumentation and optimization of instrumental and operating parameters, pointing out (i) the description, benefits and drawbacks of different kinds of nebulization and desolvation devices and the impact of more specific instrumental parameters such as the injector characteristics and the material used for the cone; and, (ii) the optimization of operating parameters, for both ICP-OES and ICP-MS. Even if it is at the margin of this tutorial review

  13. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: A tutorial review. Part II. Practical considerations

    Energy Technology Data Exchange (ETDEWEB)

    Leclercq, Amélie, E-mail: amelie.leclercq@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Nonell, Anthony, E-mail: anthony.nonell@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Todolí Torró, José Luis, E-mail: jose.todoli@ua.es [Universidad de Alicante, Departamento de Quimica Analitica, Nutricion y Bromatología, Ap. de Correos, 99, 03080 Alicante (Spain); Bresson, Carole, E-mail: carole.bresson@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Vio, Laurent, E-mail: laurent.vio@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Vercouter, Thomas, E-mail: thomas.vercouter@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Chartier, Frédéric, E-mail: frederic.chartier@cea.fr [CEA Saclay, DEN, DANS, DPC, 91191 Gif-sur-Yvette (France)

    2015-07-23

    Graphical abstract: This tutorial review is dedicated to the analysis of organic/hydro-organic matrices by ICP techniques. A state-of-the-art focusing on sample introduction, relevant operating parameters optimization and analytical strategies for elemental quantification is provided. - Highlights: • Practical considerations to perform analyses in organic/hydro-organic matrices. • Description, benefits and drawbacks of recent introduction devices. • Optimization to improve plasma tolerance towards organic/hydro-organic matrices. • Analytical strategies for elemental quantification in organic/hydro-organic matrices. - Abstract: Inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are increasingly used to carry out analyses in organic/hydro-organic matrices. The introduction of such matrices into ICP sources is particularly challenging and can be the cause of numerous drawbacks. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP sources. Part I provided theoretical considerations associated with the physico-chemical properties of such matrices, in an attempt to understand the induced phenomena. Part II of this tutorial review is dedicated to more practical considerations on instrumentation, instrumental and operating parameters, as well as analytical strategies for elemental quantification in such matrices. Two important issues are addressed in this part: the first concerns the instrumentation and optimization of instrumental and operating parameters, pointing out (i) the description, benefits and drawbacks of different kinds of nebulization and desolvation devices and the impact of more specific instrumental parameters such as the injector characteristics and the material used for the cone; and, (ii) the optimization of operating parameters, for both ICP-OES and ICP-MS. Even if it is at the margin of this tutorial review

  14. A numerical study on the effects of temperature and mass transfer in high temperature PEM fuel cells with ab-PBI membrane

    International Nuclear Information System (INIS)

    Sun, Hong; Xie, Chen; Chen, Hao; Almheiri, Saif

    2015-01-01

    Highlights: • A two-dimensional model is developed to study the HT-PEMFC with ab-PBI membrane. • The temperature distribution in the ab-PBI membrane is uneven. • With the increase of temperature, the resistance in ab-PBI membrane decreases. • Porosity has the most significant effect on the performance of HT-PEMFC. - Abstract: A two-dimensional, single-phase model is developed to study high temperature proton exchange membrane (HT-PEM) fuel cell with poly(2,5-benzimidazole) (ab-PBI) membrane. In this model, simulation region not only includes the cathode and anode, but also includes ab-PBI membrane; the continuity boundary condition at the interface between the catalyst layer (CL) and the gas diffusion layer (GDL) at each side of the cell is omitted by including the catalyst layers in the respective unified domains for the cathode and the anode. The flows, species, energy, current density are all coupled in the model. Experiments have been conducted to validate the proposed numerical simulations, and it is found that there is a good agreement between the modeling results and those obtained experimentally. By this simulation, not only the oxygen and water fraction distribution in the cathode, but also the temperature distribution and resistance distribution in the ab-PBI membrane are obtained, and the effects of the cell temperature, the porosity in the diffusion layer and its thickness on the current density are analyzed. The innovative researching results are that the temperature distribution is uneven in the ab-PBI membrane and its resistance is greatly affected by the operating temperature. Other results show that the increase of the cell temperature and the porosity in the diffusion layer, and the decrease of the diffusion layer thickness all improve the performance of HT-PEM fuel cells by promoting its internal mass transfer.

  15. Effect of Mass-Transport Limitations on the Performance of a Packed Bed Membrane Reactor for Partial Oxidations. Transport from the Membrane to the Packed Bed

    NARCIS (Netherlands)

    van Sint Annaland, M.; Kurten, U.; Kuipers, J.A.M.

    2007-01-01

    With a packed bed membrane reactor, the product yield can be significantly enhanced for partial oxidation systems, via distributive addition of oxygen to the reaction mixture along the axial coordinate of the reactor, provided that the reaction order in oxygen of the formation rate of the target

  16. Effect of mass-transport limitations on the performance of a packed bed membrane reactor for partial oxidations. Transport from the membrane to the packed bed

    NARCIS (Netherlands)

    Sint Annaland, van M.; Kurten, U.; Kuipers, J.A.M.

    2007-01-01

    With a packed bed membrane reactor, the product yield can be significantly enhanced for partial oxidation systems, via distributive addition of oxygen to the reaction mixture along the axial coordinate of the reactor, provided that the reaction order in oxygen of the formation rate of the target

  17. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: a tutorial review. Part II. Practical considerations.

    Science.gov (United States)

    Leclercq, Amélie; Nonell, Anthony; Todolí Torró, José Luis; Bresson, Carole; Vio, Laurent; Vercouter, Thomas; Chartier, Frédéric

    2015-07-23

    Inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are increasingly used to carry out analyses in organic/hydro-organic matrices. The introduction of such matrices into ICP sources is particularly challenging and can be the cause of numerous drawbacks. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP sources. Part I provided theoretical considerations associated with the physico-chemical properties of such matrices, in an attempt to understand the induced phenomena. Part II of this tutorial review is dedicated to more practical considerations on instrumentation, instrumental and operating parameters, as well as analytical strategies for elemental quantification in such matrices. Two important issues are addressed in this part: the first concerns the instrumentation and optimization of instrumental and operating parameters, pointing out (i) the description, benefits and drawbacks of different kinds of nebulization and desolvation devices and the impact of more specific instrumental parameters such as the injector characteristics and the material used for the cone; and, (ii) the optimization of operating parameters, for both ICP-OES and ICP-MS. Even if it is at the margin of this tutorial review, Electrothermal Vaporization and Laser Ablation will also be shortly described. The second issue is devoted to the analytical strategies for elemental quantification in such matrices, with particular insight into the isotope dilution technique, particularly used in speciation analysis by ICP-coupled separation techniques. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Comparison of a high temperature torch integrated sample introduction system with a desolvation system for the analysis of microsamples through inductively coupled plasma mass spectrometry

    Science.gov (United States)

    Sánchez, Raquel; Cañabate, Águeda; Bresson, Carole; Chartier, Frédéric; Isnard, Hélène; Maestre, Salvador; Nonell, Anthony; Todolí, José-Luis

    2017-03-01

    This work describes for the first time the comparison of the analytical performances obtained with a high temperature torch integrated sample introduction system (hTISIS) against those found with a commercially available desolvation system (APEX) associated with inductively coupled plasma mass spectrometry (ICP-MS). A double pass spray chamber was taken as the reference system. Similar detection limits and sensitivities were obtained in continuous injection mode at low liquid flow rates for the APEX and hTISIS operating at high temperatures. In contrast, in the air-segmented injection mode, the detection limits obtained with hTISIS at high temperatures were up to 12 times lower than those found for the APEX. Regarding memory effects, wash out times were shorter in continuous mode and peaks were narrower in air segmented mode for the hTISIS as compared to the APEX. Non spectral interferences (matrix effects) were studied with 10% nitric acid, 2% methanol, for an ICP multielemental solution and a hydro-organic matrix containing 70% (v/v) acetonitrile in water, 15 mmol L- 1 ammonium acetate and 0.5% formic acid containing lanthanide complexes. In all the cases, matrix effects were less severe for the hTISIS operating at 200 °C and the APEX than for the double pass spray chamber. Finally, two spiked reference materials (sea water and Antartic krill) were analyzed. The hTISIS operating at 200 °C gave the best results compared to those obtained with the APEX and the double pass spray chamber. In conclusion, despite the simplicity of the hTISIS, it provided, at low liquid flow rates, results similar to or better than those obtained with the by other sample introduction systems.

  19. Screening anti-tumor compounds from Ligusticum wallichii using cell membrane chromatography combined with high-performance liquid chromatography and mass spectrometry.

    Science.gov (United States)

    Zhang, Tao; Ding, Yuanyuan; An, Hongli; Feng, Liuxin; Wang, Sicen

    2015-07-14

    Tyrosine 367 Cysteine-fibroblast growth factor receptor 4 cell membrane chromatography combined with high-performance liquid chromatography and mass spectrometry was developed. Tyrosine 367 Cysteine-HEK293 cells were used as cell membrane stationary phase. Specificity and reproducibility of the cell membrane chromatography was evaluated using 1-tert-butyl-3-{2-[4-(diethylamino)butylamino]-6-(3,5-dimethoxyphenyl)pyrido[2,3-d]pyrimidin-7-yl}urea, Nimodipine and dexamethasone acetate. Then, anti-tumor components acting on Tyrosine 367 Cysteine-fibroblast growth factor receptor 4 were screened and identified from extracts of Ligusticum wallichii. Components from the extract were retained on the cell membrane chromatographic column. The retained fraction was directly eluted into high-performance liquid chromatography with mass spectrometry system for separation and identification. Finally, Levistolide A was identified as an active component from Ligusticum wallichii extracts. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide-formazan colorimetric assay revealed that Levistolide A inhibits proliferation of overexpressing the mutated receptor cells with dose-dependent manner. Phosphorylation of fibroblast growth factor receptor 4 was also decrease under Levistolide A treatment. Flex dock simulation verified that Levistolide A could bind with the tyrosine kinase domain of fibroblast growth factor receptor 4. Therefore, Levistolide A screened by the cell membrane chromatography combined with high-performance liquid chromatography and mass spectrometry can arrest cell growth. In conclusion, the two-dimensional high-performance liquid chromatography method can screen and identify potential anti-tumor ingredients which specifically act on the tyrosine kinase domain of the mutated fibroblast growth factor receptor 4. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  20. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: A tutorial review. Part I. Theoretical considerations

    International Nuclear Information System (INIS)

    Leclercq, Amélie; Nonell, Anthony; Todolí Torró, José Luis; Bresson, Carole; Vio, Laurent; Vercouter, Thomas; Chartier, Frédéric

    2015-01-01

    Highlights: • Tutorial review addressed to beginners or more experienced analysts. • Theoretical background of effects caused by organic matrices on ICP techniques. • Spatial distribution of carbon species and analytes in plasma. • Carbon spectroscopic and non-spectroscopic interferences in ICP. - Abstract: Due to their outstanding analytical performances, inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are widely used for multi-elemental measurements and also for isotopic characterization in the case of ICP-MS. While most studies are carried out in aqueous matrices, applications involving organic/hydro-organic matrices become increasingly widespread. This kind of matrices is introduced in ICP based instruments when classical “matrix removal” approaches such as acid digestion or extraction procedures cannot be implemented. Due to the physico-chemical properties of organic/hydro-organic matrices and their associated effects on instrumentation and analytical performances, their introduction into ICP sources is particularly challenging and has become a full topic. In this framework, numerous theoretical and phenomenological studies of these effects have been performed in the past, mainly by ICP-OES, while recent literature is more focused on applications and associated instrumental developments. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP-OES and ICP-MS. The present Part I, provides theoretical considerations in connection with the physico-chemical properties of organic/hydro-organic matrices, in order to better understand the induced phenomena. This focal point is divided in four chapters highlighting: (i) the impact of organic/hydro-organic matrices from aerosol generation to atomization/excitation/ionization processes; (ii) the production of carbon molecular constituents and their spatial distribution in the

  1. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: a tutorial review. Part I. Theoretical considerations.

    Science.gov (United States)

    Leclercq, Amélie; Nonell, Anthony; Todolí Torró, José Luis; Bresson, Carole; Vio, Laurent; Vercouter, Thomas; Chartier, Frédéric

    2015-07-23

    Due to their outstanding analytical performances, inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are widely used for multi-elemental measurements and also for isotopic characterization in the case of ICP-MS. While most studies are carried out in aqueous matrices, applications involving organic/hydro-organic matrices become increasingly widespread. This kind of matrices is introduced in ICP based instruments when classical "matrix removal" approaches such as acid digestion or extraction procedures cannot be implemented. Due to the physico-chemical properties of organic/hydro-organic matrices and their associated effects on instrumentation and analytical performances, their introduction into ICP sources is particularly challenging and has become a full topic. In this framework, numerous theoretical and phenomenological studies of these effects have been performed in the past, mainly by ICP-OES, while recent literature is more focused on applications and associated instrumental developments. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP-OES and ICP-MS. The present Part I, provides theoretical considerations in connection with the physico-chemical properties of organic/hydro-organic matrices, in order to better understand the induced phenomena. This focal point is divided in four chapters highlighting: (i) the impact of organic/hydro-organic matrices from aerosol generation to atomization/excitation/ionization processes; (ii) the production of carbon molecular constituents and their spatial distribution in the plasma with respect to analytes repartition; (iii) the subsequent modifications of plasma fundamental properties; and (iv) the resulting spectroscopic and non spectroscopic interferences. This first part of this tutorial review is addressed either to beginners or to more experienced scientists who are interested in the

  2. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: A tutorial review. Part I. Theoretical considerations

    Energy Technology Data Exchange (ETDEWEB)

    Leclercq, Amélie, E-mail: amelie.leclercq@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Nonell, Anthony, E-mail: anthony.nonell@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Todolí Torró, José Luis, E-mail: jose.todoli@ua.es [Universidad de Alicante, Departamento de Quimica Analitica, Nutricion y Bromatología, Ap. de Correos, 99, 03080 Alicante (Spain); Bresson, Carole, E-mail: carole.bresson@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Vio, Laurent, E-mail: laurent.vio@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Vercouter, Thomas, E-mail: thomas.vercouter@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Chartier, Frédéric, E-mail: frederic.chartier@cea.fr [CEA Saclay, DEN, DANS, DPC, 91191 Gif-sur-Yvette (France)

    2015-07-23

    Highlights: • Tutorial review addressed to beginners or more experienced analysts. • Theoretical background of effects caused by organic matrices on ICP techniques. • Spatial distribution of carbon species and analytes in plasma. • Carbon spectroscopic and non-spectroscopic interferences in ICP. - Abstract: Due to their outstanding analytical performances, inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are widely used for multi-elemental measurements and also for isotopic characterization in the case of ICP-MS. While most studies are carried out in aqueous matrices, applications involving organic/hydro-organic matrices become increasingly widespread. This kind of matrices is introduced in ICP based instruments when classical “matrix removal” approaches such as acid digestion or extraction procedures cannot be implemented. Due to the physico-chemical properties of organic/hydro-organic matrices and their associated effects on instrumentation and analytical performances, their introduction into ICP sources is particularly challenging and has become a full topic. In this framework, numerous theoretical and phenomenological studies of these effects have been performed in the past, mainly by ICP-OES, while recent literature is more focused on applications and associated instrumental developments. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP-OES and ICP-MS. The present Part I, provides theoretical considerations in connection with the physico-chemical properties of organic/hydro-organic matrices, in order to better understand the induced phenomena. This focal point is divided in four chapters highlighting: (i) the impact of organic/hydro-organic matrices from aerosol generation to atomization/excitation/ionization processes; (ii) the production of carbon molecular constituents and their spatial distribution in the

  3. Multiple inert gas elimination technique by micropore membrane inlet mass spectrometry--a comparison with reference gas chromatography.

    Science.gov (United States)

    Kretzschmar, Moritz; Schilling, Thomas; Vogt, Andreas; Rothen, Hans Ulrich; Borges, João Batista; Hachenberg, Thomas; Larsson, Anders; Baumgardner, James E; Hedenstierna, Göran

    2013-10-15

    The mismatching of alveolar ventilation and perfusion (VA/Q) is the major determinant of impaired gas exchange. The gold standard for measuring VA/Q distributions is based on measurements of the elimination and retention of infused inert gases. Conventional multiple inert gas elimination technique (MIGET) uses gas chromatography (GC) to measure the inert gas partial pressures, which requires tonometry of blood samples with a gas that can then be injected into the chromatograph. The method is laborious and requires meticulous care. A new technique based on micropore membrane inlet mass spectrometry (MMIMS) facilitates the handling of blood and gas samples and provides nearly real-time analysis. In this study we compared MIGET by GC and MMIMS in 10 piglets: 1) 3 with healthy lungs; 2) 4 with oleic acid injury; and 3) 3 with isolated left lower lobe ventilation. The different protocols ensured a large range of normal and abnormal VA/Q distributions. Eight inert gases (SF6, krypton, ethane, cyclopropane, desflurane, enflurane, diethyl ether, and acetone) were infused; six of these gases were measured with MMIMS, and six were measured with GC. We found close agreement of retention and excretion of the gases and the constructed VA/Q distributions between GC and MMIMS, and predicted PaO2 from both methods compared well with measured PaO2. VA/Q by GC produced more widely dispersed modes than MMIMS, explained in part by differences in the algorithms used to calculate VA/Q distributions. In conclusion, MMIMS enables faster measurement of VA/Q, is less demanding than GC, and produces comparable results.

  4. Proteomic screen for multiprotein complexes in synaptic plasma membrane from rat hippocampus by blue native gel electrophoresis and tandem mass spectrometry.

    Science.gov (United States)

    Li, Xuanwen; Xie, Chunliang; Jin, Qihui; Liu, Mingjun; He, Quanyuan; Cao, Rui; Lin, Yong; Li, Jianglin; Li, Yan; Chen, Ping; Liang, Songping

    2009-07-01

    Neuronal synapses are specialized sites for information exchange between neurons. Many diseases, such as addiction and mood disorders, likely result from altered expression of synaptic proteins, or altered formation of synaptic complexes involved in neurotransmission or neuroplasticity. A detailed description of native multiprotein complexes in synaptic plasma membranes (PM) is therefore essential for understanding biological mechanisms and disease processes. For the first time in this study, two-dimensional Blue Native/SDS-PAGE electrophoresis, combined with tandem mass spectrometry, was used to screen multiprotein complexes in synaptic plasma membranes from rat hippocampus. As a result, 514 unique proteins were identified, of which 36% were integral membrane proteins. In addition, 19 potentially novel and known heterooligomeric multiprotein complexes were found, such as the SNARE and ATPase complexes. A potentially novel protein complex, involving syntaxin, synapsin I and Na+/K+ ATPase alpha-1, was further confirmed by co-immunoprecipitation and immunofluorescence staining. As demonstrated here, Blue Native-PAGE is a powerful tool for the separation of hydrophobic membrane proteins. The combination of Blue Native-PAGE and mass spectrometry could systematically identify multiprotein complexes.

  5. Graphene oxide membrane as an efficient extraction and ionization substrate for spray-mass spectrometric analysis of malachite green and its metabolite in fish samples.

    Science.gov (United States)

    Wei, Shih-Chun; Fan, Shen; Lien, Chia-Wen; Unnikrishnan, Binesh; Wang, Yi-Sheng; Chu, Han-Wei; Huang, Chih-Ching; Hsu, Pang-Hung; Chang, Huan-Tsung

    2018-03-20

    A graphene oxide (GO) nanosheet-modified N + -nylon membrane (GOM) has been prepared and used as an extraction and spray-ionization substrate for robust mass spectrometric detection of malachite green (MG), a highly toxic disinfectant in liquid samples and fish meat. The GOM is prepared by self-deposition of GO thin film onto an N + -nylon membrane, which has been used for efficient extraction of MG in aquaculture water samples or homogenized fish meat samples. Having a dissociation constant of 2.17 × 10 -9  M -1 , the GOM allows extraction of approximately 98% of 100 nM MG. Coupling of the GOM-spray with an ion-trap mass spectrometer allows quantitation of MG in aquaculture freshwater and seawater samples down to nanomolar levels. Furthermore, the system possesses high selectivity and sensitivity for the quantitation of MG and its metabolite (leucomalachite green) in fish meat samples. With easy extraction and efficient spray ionization properties of GOM, this membrane spray-mass spectrometry technique is relatively simple and fast in comparison to the traditional LC-MS/MS methods for the quantitation of MG and its metabolite in aquaculture products. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Effect of internal pressure and gas/liquid interface area on the CO mass transfer coefficient using hollow fibre membranes as a high mass transfer gas diffusing system for microbial syngas fermentation.

    Science.gov (United States)

    Yasin, Muhammad; Park, Shinyoung; Jeong, Yeseul; Lee, Eun Yeol; Lee, Jinwon; Chang, In Seop

    2014-10-01

    This study proposed a submerged hollow fibre membrane bioreactor (HFMBR) system capable of achieving high carbon monoxide (CO) mass transfer for applications in microbial synthesis gas conversion systems. Hydrophobic polyvinylidene fluoride (PVDF) membrane fibres were used to fabricate a membrane module, which was used for pressurising CO in water phase. Pressure through the hollow fibre lumen (P) and membrane surface area per unit working volume of the liquid (A(S)/V(L)) were used as controllable parameters to determine gas-liquid volumetric mass transfer coefficient (k(L)a) values. We found a k(L)a of 135.72 h(-1) when P was 93.76 kPa and AS/VL was fixed at 27.5m(-1). A higher k(L)a of 155.16 h(-1) was achieved by increasing AS/VL to 62.5m(-1) at a lower P of 37.23 kPa. Practicality of HFMBR to support microbial growth and organic product formation was assessed by CO/CO2 fermentation using Eubacterium limosum KIST612. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Improvement of a sample preparation method assisted by sodium deoxycholate for mass-spectrometry-based shotgun membrane proteomics.

    Science.gov (United States)

    Lin, Yong; Lin, Haiyan; Liu, Zhonghua; Wang, Kunbo; Yan, Yujun

    2014-11-01

    In current shotgun-proteomics-based biological discovery, the identification of membrane proteins is a challenge. This is especially true for integral membrane proteins due to their highly hydrophobic nature and low abundance. Thus, much effort has been directed at sample preparation strategies such as use of detergents, chaotropes, and organic solvents. We previously described a sample preparation method for shotgun membrane proteomics, the sodium deoxycholate assisted method, which cleverly circumvents many of the challenges associated with traditional sample preparation methods. However, the method is associated with significant sample loss due to the slightly weaker extraction/solubilization ability of sodium deoxycholate when it is used at relatively low concentrations such as 1%. Hence, we present an enhanced sodium deoxycholate sample preparation strategy that first uses a high concentration of sodium deoxycholate (5%) to lyse membranes and extract/solubilize hydrophobic membrane proteins, and then dilutes the detergent to 1% for a more efficient digestion. We then applied the improved method to shotgun analysis of proteins from rat liver membrane enriched fraction. Compared with other representative sample preparation strategies including our previous sodium deoxycholate assisted method, the enhanced sodium deoxycholate method exhibited superior sensitivity, coverage, and reliability for the identification of membrane proteins particularly those with high hydrophobicity and/or multiple transmembrane domains. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Determination of extremely low 236U/238U isotope ratios in environmental samples by sector-field inductively coupled plasma mass spectrometry using high-efficiency sample introduction

    International Nuclear Information System (INIS)

    Boulyga, Sergei F.; Heumann, Klaus G.

    2006-01-01

    A method by inductively coupled plasma mass spectrometry (Icp-Ms) was developed which allows the measurement of 236 U at concentration ranges down to 3 x 10 -14 g g -1 and extremely low 236 U/ 238 U isotope ratios in soil samples of 10 -7 . By using the high-efficiency solution introduction system APEX in connection with a sector-field ICP-MS a sensitivity of more than 5000 counts fg -1 uranium was achieved. The use of an aerosol desolvating unit reduced the formation rate of uranium hydride ions UH + /U + down to a level of 10 -6 . An abundance sensitivity of 3 x 10 -7 was observed for 236 U/ 238 U isotope ratio measurements at mass resolution 4000. The detection limit for 236 U and the lowest detectable 236 U/ 238 U isotope ratio were improved by more than two orders of magnitude compared with corresponding values by alpha spectrometry. Determination of uranium in soil samples collected in the vicinity of Chernobyl nuclear power plant (NPP) resulted in that the 236 U/ 238 U isotope ratio is a much more sensitive and accurate marker for environmental contamination by spent uranium in comparison to the 235 U/ 238 U isotope ratio. The ICP-MS technique allowed for the first time detection of irradiated uranium in soil samples even at distances more than 200 km to the north of Chernobyl NPP (Mogilev region). The concentration of 236 U in the upper 0-10 cm soil layers varied from 2 x 10 -9 g g -1 within radioactive spots close to the Chernobyl NPP to 3 x 10 -13 g g -1 on a sampling site located by >200 km from Chernobyl

  9. Determination of extremely low (236)U/(238)U isotope ratios in environmental samples by sector-field inductively coupled plasma mass spectrometry using high-efficiency sample introduction.

    Science.gov (United States)

    Boulyga, Sergei F; Heumann, Klaus G

    2006-01-01

    A method by inductively coupled plasma mass spectrometry (ICP-MS) was developed which allows the measurement of (236)U at concentration ranges down to 3 x 10(-14)g g(-1) and extremely low (236)U/(238)U isotope ratios in soil samples of 10(-7). By using the high-efficiency solution introduction system APEX in connection with a sector-field ICP-MS a sensitivity of more than 5,000 counts fg(-1) uranium was achieved. The use of an aerosol desolvating unit reduced the formation rate of uranium hydride ions UH(+)/U(+) down to a level of 10(-6). An abundance sensitivity of 3 x 10(-7) was observed for (236)U/(238)U isotope ratio measurements at mass resolution 4000. The detection limit for (236)U and the lowest detectable (236)U/(238)U isotope ratio were improved by more than two orders of magnitude compared with corresponding values by alpha spectrometry. Determination of uranium in soil samples collected in the vicinity of Chernobyl nuclear power plant (NPP) resulted in that the (236)U/(238)U isotope ratio is a much more sensitive and accurate marker for environmental contamination by spent uranium in comparison to the (235)U/(238)U isotope ratio. The ICP-MS technique allowed for the first time detection of irradiated uranium in soil samples even at distances more than 200 km to the north of Chernobyl NPP (Mogilev region). The concentration of (236)U in the upper 0-10 cm soil layers varied from 2 x 10(-9)g g(-1) within radioactive spots close to the Chernobyl NPP to 3 x 10(-13)g g(-1) on a sampling site located by >200 km from Chernobyl.

  10. Determination of Cu, Mn, Ni and Sn in gasoline by electrothermal vaporization inductively coupled plasma mass spectrometry, and emulsion sample introduction

    International Nuclear Information System (INIS)

    Saint'Pierre, Tatiana D.; Dias, Lucia Felicidade; Pozebon, Dirce; Aucelio, Ricardo Q.; Curtius, Adilson J.; Welz, Bernhard

    2002-01-01

    Trace metals in fuels, except in the case of additives, are usually undesirable and normally they occur in very low concentrations in gasoline, requiring sensitive techniques for their determination. Coupling of electrothermal vaporization with inductively coupled plasma mass spectrometry minimizes the problems related to the introduction of organic solvents into the plasma. Furthermore, sample preparation as oil-in-water emulsions reduces problems related to gasoline analysis. In this work, a method for determination of Cu, Mn, Ni and Sn in gasoline is proposed. Samples were prepared by forming a 10-fold diluted emulsion with a surfactant (Triton X-100), after treatment with concentrated HNO 3 . The sample emulsion was pre-concentrated in the graphite tube by repeated pipetting and drying. External calibration was used with aqueous standards in a purified gasoline emulsion. Six samples from different gas stations were analyzed, and the analyte concentrations were found to be in the μg l -1 range or below. The limits of detection were 0.22, 0.02, 0.38 and 0.03 μg l -1 for Cu, Mn, Ni and Sn, respectively. The accuracy of the method was estimated using a recovery test

  11. A comparison of continuous pneumatic nebulization and flow injection-direct injection nebulization for sample introduction in inductively coupled plasma-mass spectrometry

    International Nuclear Information System (INIS)

    Crain, J.S.; Kiely, J.T.

    1995-08-01

    Dilute nitric acid blanks and solutions containing Ni, Cd, Pb, and U (including two laboratory waste samples) were analyzed eighteen times over a two-month period using inductively coupled plasma-mass spectrometry (ICP-MS). Two different sample introduction techniques were employed: flow injection-direct injection nebulization (FI-DIN) and continuous pneumatic nebulization (CPN). Using comparable instrumental measurement procedures, FI-DIN analyses were 33% faster and generated 52% less waste than CPN analyses. Instrumental limits of detection obtained with FI-DIN and CPN were comparable but not equivalent (except in the case of Pb) because of nebulizer-related differences in sensitivity (i.e., signal per unit analyte concentration) and background. Substantial and statistically significant differences were found between FI-DIN and CPN Ni determinations, and in the case of the laboratory waste samples, there were also small but statistically significant differences between Cd determinations. These small (2 to 3%) differences were not related to polyatomic ion interference (e.g., 95 Mo 16 O + ), but in light of the time savings and waste reduction to be realized, they should not preclude the use of FI-DIN in place of CPN for determination of Cd, Pb, U and chemically

  12. Direct introduction of volatile carbon compounds into the spray chamber of an inductively coupled plasma mass spectrometer: Sensitivity enhancement for selenium

    International Nuclear Information System (INIS)

    Kovacevic, Miroslav; Goessler, Walter

    2005-01-01

    The effect of signal enhancement of elements with ionization potentials in the range from 9 to 11 eV by carbon-containing compounds is a well-known phenomenon in inductively coupled plasma mass spectrometry (ICPMS). It has traditionally been exploited through the addition of organic solvents to the sample matrix or to the mobile phase to improve sensitivity. In the present work, aqueous solutions of volatile carbon compounds (acetone, methanol and acetic acid) were directly introduced into the thermostatted spray chamber rather than being added to the sample matrix. It is presumed that no aerosol is produced from these solutions and only vapors of organic compounds are swept into the plasma together with the sample aerosol. When a 0.40 mol l -1 aqueous solution of acetone was introduced directly into the spray chamber, the signals for arsenic and selenium were enhanced by a factor of 4.2. The usefulness of this approach was demonstrated through the achievement of lower instrumental detection limits for selenium at m/z 82 (0.1 ng ml -1 ) compared to the system without direct introduction of volatile carbon compounds (0.5 ng ml -1 ). The method was successfully applied in the determination of traces of selenium in natural water, urine and bovine liver reference material

  13. A model of protocell based on the introduction of a semi-permeable membrane in a stochastic model of catalytic reaction networks

    Directory of Open Access Journals (Sweden)

    Marco Villani

    2013-09-01

    Full Text Available In this work we introduce some preliminary analyses on the role of a semi-permeable membrane in the dynamics of a stochastic model of catalytic reaction sets (CRSs of molecules. The results of the simulations performed on ensembles of randomly generated reaction schemes highlight remarkable differences between this very simple protocell description model and the classical case of the continuous stirred-tank reactor (CSTR. In particular, in the CSTR case, distinct simulations with the same reaction scheme reach the same dynamical equilibrium, whereas, in the protocell case, simulations with identical reaction schemes can reach very different dynamical states, despite starting from the same initial conditions.

  14. A comparison of micropore membrane inlet mass spectrometry-derived pulmonary shunt measurement with Riley shunt in a porcine model.

    Science.gov (United States)

    Duenges, Bastian; Vogt, Andreas; Bodenstein, Marc; Wang, Hemei; Böhme, Stefan; Röhrig, Bernd; Baumgardner, James E; Markstaller, Klaus

    2009-12-01

    The multiple inert gas elimination technique was developed to measure shunt and the ratio of alveolar ventilation to simultaneous alveolar capillary blood flow in any part of the lung (V(A)'/Q') distributions. Micropore membrane inlet mass spectrometry (MMIMS), instead of gas chromatography, has been introduced for inert gas measurement and shunt determination in a rabbit lung model. However, agreement with a frequently used and accepted method for quantifying deficits in arterial oxygenation has not been established. We compared MMIMS-derived shunt (M-S) as a fraction of total cardiac output (CO) with Riley shunt (R-S) derived from the R-S formula in a porcine lung injury model. To allow a broad variance of atelectasis and therefore shunt fraction, 8 sham animals did not receive lavage, and 8 animals were treated by lung lavages with 30 mL/kg warmed lactated Ringer's solution as follows: 2 animals were lavaged once, 5 animals twice, and 1 animal 3 times. Variables were recorded at baseline and twice after induction of lung injury (T1 and T2). Retention data of sulfur hexafluoride, krypton, desflurane, enflurane, diethyl ether, and acetone were analyzed by MMIMS, and M-S was derived using a known algorithm for the multiple inert gas elimination technique. Standard formulas were used for the calculation of R-S. Forty-four pairs of M-S and R-S were recorded. M-S ranged from 0.1% to 35.4% and R-S from 3.7% to 62.1%. M-S showed a correlation with R-S described by linear regression: M-S = -4.26 + 0.59 x R-S (r(2) = 0.83). M-S was on average lower than R-S (mean = -15.0% CO, sd = 6.5% CO, and median = -15.1), with lower and upper limits of agreement of -28.0% and -2.0%, respectively. The lower and upper limits of the 95% confidence intervals were -17.0 and -13.1 (P < 0.001, Student's t-test). Shunt derived from MMIMS inert gas retention data correlated well with R-S during breathing of oxygen. Shunt as derived by MMIMS was generally less than R-S.

  15. Effect of mass-transport limitations on the performance of a packed bed membrane reactor for partial oxidations. Intraparticle mass transport

    NARCIS (Netherlands)

    Sint Annaland, van M.; Kurten, U.; Kuipers, J.A.M.

    2007-01-01

    For partial oxidation systems, where the reaction order in oxygen of the formation rate of the target product is smaller than the reaction order in oxygen of the consecutive reaction rate toward the waste product, a packed bed membrane reactor can be applied to distributively dose oxygen along the

  16. Effect of Mass-Transport Limitations on the Performance of a Packed Bed Membrane Reactor for Partial Oxidations. Intraparticle Mass Transport

    NARCIS (Netherlands)

    van Sint Annaland, M.; Kurten, U.; Kuipers, J.A.M.

    2007-01-01

    For partial oxidation systems, where the reaction order in oxygen of the formation rate of the target product is smaller than the reaction order in oxygen of the consecutive reaction rate toward the waste product, a packed bed membrane reactor can be applied to distributively dose oxygen along the

  17. Metamaterial membranes

    International Nuclear Information System (INIS)

    Restrepo-Flórez, Juan Manuel; Maldovan, Martin

    2017-01-01

    We introduce a new class of metamaterial device to achieve separation of compounds by using coordinate transformations and metamaterial theory. By rationally designing the spatial anisotropy for mass diffusion, we simultaneously concentrate different compounds in different spatial locations, leading to separation of mixtures across a metamaterial membrane. The separation of mixtures into their constituent compounds is critically important in biophysics, biomedical, and chemical applications. We present a practical case where a mixture of oxygen and nitrogen diffusing through a polymeric planar matrix is separated. This work opens doors to new paradigms in membrane separations via coordinate transformations and metamaterials by introducing novel properties and unconventional mass diffusion phenomena. (paper)

  18. Introduction to renewable energy

    CERN Document Server

    Nelson, Vaughn C

    2011-01-01

    IntroductionEnergy and SocietyTypes of EnergyRenewable EnergyAdvantages/DisadvantagesEconomicsGlobal WarmingOrder of Magnitude EstimatesGrowth (Exponential)SolutionsEnergyIntroductionDefinition of Energy and PowerHeatThermodynamicsEnergy Dilemma in Light of the Laws of ThermodynamicsUse of Fossil FuelsNuclearFinite ResourceSummarySunSolar PowerElectromagnetic SpectrumEnergy Balance of the EarthEarth-Sun MotionInsolationSolar ResourceGreenhouse EffectHeat Transfer and StorageIntroductionConductionConvectionRadiationThermal MassSeasonal Heating or CoolingThermal ComfortSolar Heating and CoolingB

  19. Screening antiallergic components from Carthamus tinctorius using rat basophilic leukemia 2H3 cell membrane chromatography combined with high-performance liquid chromatography and tandem mass spectrometry.

    Science.gov (United States)

    Han, Shengli; Huang, Jing; Cui, Ronghua; Zhang, Tao

    2015-02-01

    Carthamus tinctorius, used in traditional Chinese medicine, has many pharmacological effects, such as anticoagulant effects, antioxidant effects, antiaging effects, regulation of gene expression, and antitumor effects. However, there is no report on the antiallergic effects of the components in C. tinctorius. In the present study, we investigated the antiallergic components of C. tinctorius and its mechanism of action. A rat basophilic leukemia 2H3/cell membrane chromatography coupled online with high-performance liquid chromatography and tandem mass spectrometry method was developed to screen antiallergic components from C. tinctorius. The screening results showed that Hydroxysafflor yellow A, from C. tinctorius, was the targeted component that retained on the rat basophilic leukemia 2H3/cell membrane chromatography column. We measured the amount of β-hexosaminidase and histamine released in mast cells and the key markers of degranulation. The release assays showed that Hydroxysafflor yellow A could attenuate the immunoglobulin E induced release of allergic cytokines without affecting cell viability from 1.0 to 50.0 μM. In conclusion, the established rat basophilic leukemia 2H3 cell membrane chromatography coupled with online high-performance liquid chromatography and tandem mass spectrometry method successfully screened and identified Hydroxysafflor yellow A from C. tinctorius as a potential antiallergic component. Pharmacological analysis elucidated that Hydroxysafflor yellow A is an effective natural component for inhibiting immunoglobulin E-antigen-mediated degranulation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Metastasis-related plasma membrane proteins of human breast cancer cells identified by comparative quantitative mass spectrometry

    DEFF Research Database (Denmark)

    Leth-Larsen, Rikke; Lund, Rikke; Hansen, Helle V

    2009-01-01

    The spread of cancer cells from a primary tumor to form metastasis at distant sites is a complex multi-step process. The cancer cell proteins, and plasma membrane proteins in particular, involved in this process are poorly defined and a study of the very early events of the metastatic process using...... clinical samples or in vitro assays is not feasible. We have used a unique model system consisting of two isogenic human breast cancer cell lines that are equally tumorigenic in mice, but while one gives rise to metastasis, the other disseminates single cells that remain dormant at distant organs. Membrane...... purification and comparative quantitative LC-MS/MS proteomic analysis identified 13 membrane proteins that were expressed at higher levels and 3 that were under-expressed in the metastatic compared to the non-metastatic cell line from a total of 1919 identified protein entries. Among the proteins were ecto-5...

  1. Identification of ftalates used as additives in the geo membrane of a la Florida reservoir through gas chromatography-mass spectrometry

    International Nuclear Information System (INIS)

    Blanco, M.; Rico, G.; Pargada, L.; Aguiar, E.; Castillo, F.

    2009-01-01

    This article studies the behaviour of the plastified poly (vinyl chloride) (PVC-P) applied as synthetic geo membrane for the waterproofing of the La Florida reservoir. We show the results of the initial examen of its properties and its most significant characteristics eighteen years after being applied. Furthermore we isolate and identify the quantitative and qualitative aspects of the plasticizers used in its formula through infrared spectroscopy, gas chromatography and mass spectrometry technic. We have identified as the said plasticizers di-n-octyl phthalate, di-n-decyl phthalate and n-decyl n-octyl phthalate, and we calculate the joint average molecular weight using Wilsons equation. The results found that the geo membranes we have studied has shown an excellent behaviour along through time. (Author) 53 refs

  2. Mass Spectrometric Determination of the Effect of Surface Deactivation on Membranes Used for In-Situ Sampling of Cerebrospinal Fluid (CSF

    Directory of Open Access Journals (Sweden)

    Torgny Undin

    2018-05-01

    Full Text Available In this paper, a strategy for structured monitoring of surface modifications to control protein adsorption to membrane structures is presented. The already established on-surface enzymatic digestion (oSED method combined with nano-liquid chromatography and tandem mass spectrometry (LC-MS/MS analysis was employed for the analysis of proteins in ventricular cerebrospinal fluid (vCSF from neurointensive care patients. Protein adsorption was studied by in-situ sampling in a temporally resolved manner on both immobilized native and Pluronic-deactivated membranes. Deactivation was significantly reducing the protein adsorption but it also induced novel selective properties of the surface. The proposed versatile strategy will facilitate protein-biomaterial, protein-polymer, protein-protein interaction studies in the future.

  3. The effective recovery of praseodymium from mixed rare earths via a hollow fiber supported liquid membrane and its mass transfer related

    International Nuclear Information System (INIS)

    Wannachod, Pharannalak; Chaturabul, Srestha; Pancharoen, Ura; Lothongkum, Anchaleeporn W.; Patthaveekongka, Weerawat

    2011-01-01

    Graphical abstract: Display Omitted Research highlights: → Maximum percentage of praseodymium extraction at 91.7% from 10% (v/v) bis (2,4,4-trimethylpentyl) phosphinic acid as extractant carrier in multi cycle operation through single HFLSM module. → Mass transfer mechanism of this system was investigated. → The rate-controlling step of this system was the diffusion of praseodymium ions through the film layer between the feed solution and the liquid membrane. → Model prediction of the dimensionless concentrations and separation factors showed promising agreement with the experimental data. - Abstract: The recovery of praseodymium from mixed rare earths via a hollow fiber supported liquid membrane (HFSLM) was examined. Bis(2,4,4-trimethylpentyl) phosphinic acid - known as Cyanex 272 - was used as an extractant carrier. The stripping solution was hydrochloric acid solution. The experiments examined in functions of the concentrations of the carrier in liquid membrane, the (initial) pH's of initial feed solution within the acidic-pH range, the concentrations of hydrochloric acid, the flow rates of feed and stripping solution, and the operation mode of runs through the hollow fiber module. In addition, the influence of circulation of the stripping solution at various numbers of runs through the HFSLM on the outlet concentration of praseodymium ions in the stripping solution was observed. Mass transfer mechanism in the system was investigated. Extraction equilibrium constant (K ex ), distribution ratio (D), permeability (P) and mass transfer coefficients were determined. The aqueous-phase mass-transfer coefficient (k i ) and organic-phase mass-transfer coefficient (k m ) were reported to 0.0103 and 0.788 cm s -1 , respectively, in which k m is much higher than the k i . Thus it suggests the rate-controlling step is the diffusion of praseodymium ions through the film layer between the feed solution and the liquid membrane. Model prediction of the dimensionless

  4. Mutual influence of the Na+ and Cs+ ions during their mass electrotransport through a perfluorinated sulfocation membrane

    International Nuclear Information System (INIS)

    Zezina, E.A.; Popkov, Yu.M.; Timashev, S.F.

    1997-01-01

    It is shown that by the Na + and Cs + ions sorption equilibrium conditions in perfluorinated cation-exchange membranes from the 0.1M NaCl and 0.1M CsCl mixtures the Cs + ions are sorbed primarily. The effective self-diffusion coefficients of the Na + and Cs + ions from individual solutions within the range of 0.01-1.00 M concentrations and in the above-mentioned equimolar mixture are found. It is shown that the membranes moisture content is the determining factor for the Cs + ions electrodialysis separation fro the above-mentioned electrolytes mixture

  5. C_1_8-attached membrane funnel-based spray ionization mass spectrometry for quantification of anti-diabetic drug from human plasma

    International Nuclear Information System (INIS)

    Li, Wan; Chen, Xiangfeng; Wong, Y.-L. Elaine; Hung, Y.-L. Winnie; Wang, Ze; Deng, Liulin; Dominic Chan, T.-W.

    2016-01-01

    In this work, sorbent-attached membrane funnel-based spray ionization mass spectrometry was explored for quantitative analysis of anti-diabetic drugs spiked in human plasma. C_1_8-attached membrane funnel was fabricated for in situ extraction and clean-up to alleviate matrix suppression effect in the ionization process. Repaglinide was used as a target analyte of anti-diabetic drugs. Under optimal working conditions, good linearity (R"2 > 0.99) was obtained in the concentration range of 1–100 ng mL"−"1. The method detection limit of target drugs spiked in the human plasma was around 0.30 ng mL"−"1. Through the application of an isotope-labeled internal standard, the signal fluctuation caused by residual background matrices was largely alleviated and the precision of measurement (RSD) was below 15%. The recovery of repaglinide for 5, 25, and 100 ng mL"−"1 of spiked human plasma matrixes ranged from 87% to 112%. The developed method was successfully applied to determine repaglinide in plasma volunteers who orally received a dose of drug association. Our results demonstrated that membrane funnel-based spray is a simple and sensitive method for rapid screening analysis of complex biological samples. - Highlights: • Sorbent attached membrane funnel based spray platform was used for drug determination in human plasma. • The matrix suppression effect of human plasma was largely eliminated. • The method was applied to determine repaglinide in plasma volunteers. • Membrane funnel-based spray is promising for analysis of biological samples.

  6. C{sub 18}-attached membrane funnel-based spray ionization mass spectrometry for quantification of anti-diabetic drug from human plasma

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wan [Department of Chemistry, The Chinese University of Hong Kong, Hong Kong Special Administrative Region (Hong Kong); Chen, Xiangfeng, E-mail: xiangfchensdas@163.com [Department of Chemistry, The Chinese University of Hong Kong, Hong Kong Special Administrative Region (Hong Kong); Shandong Analysis and Test Centre, Shandong Academy of Sciences, Jinan, Shandong (China); Wong, Y.-L. Elaine; Hung, Y.-L. Winnie; Wang, Ze; Deng, Liulin [Department of Chemistry, The Chinese University of Hong Kong, Hong Kong Special Administrative Region (Hong Kong); Dominic Chan, T.-W., E-mail: twdchan@cuhk.edu.hk [Department of Chemistry, The Chinese University of Hong Kong, Hong Kong Special Administrative Region (Hong Kong)

    2016-08-24

    In this work, sorbent-attached membrane funnel-based spray ionization mass spectrometry was explored for quantitative analysis of anti-diabetic drugs spiked in human plasma. C{sub 18}-attached membrane funnel was fabricated for in situ extraction and clean-up to alleviate matrix suppression effect in the ionization process. Repaglinide was used as a target analyte of anti-diabetic drugs. Under optimal working conditions, good linearity (R{sup 2} > 0.99) was obtained in the concentration range of 1–100 ng mL{sup −1}. The method detection limit of target drugs spiked in the human plasma was around 0.30 ng mL{sup −1}. Through the application of an isotope-labeled internal standard, the signal fluctuation caused by residual background matrices was largely alleviated and the precision of measurement (RSD) was below 15%. The recovery of repaglinide for 5, 25, and 100 ng mL{sup −1} of spiked human plasma matrixes ranged from 87% to 112%. The developed method was successfully applied to determine repaglinide in plasma volunteers who orally received a dose of drug association. Our results demonstrated that membrane funnel-based spray is a simple and sensitive method for rapid screening analysis of complex biological samples. - Highlights: • Sorbent attached membrane funnel based spray platform was used for drug determination in human plasma. • The matrix suppression effect of human plasma was largely eliminated. • The method was applied to determine repaglinide in plasma volunteers. • Membrane funnel-based spray is promising for analysis of biological samples.

  7. Analysis by Mass Spectrometry of the Polar Lipids from the Cellular Membrane of Thermophilic Lactic Acid Bacteria

    Directory of Open Access Journals (Sweden)

    A. M. Seldes

    2000-03-01

    Full Text Available Fast atom bombardment (FAB technique was employed to determine the structure of polar lipids from the cellular membrane of Lactobacillus delbruekii ssp. bulgaricus and Streptococcus salivarius ssp. thermophilus. Analysis of spectra provided useful information about the molecular species and aminoacids constituents of the samples.

  8. Large Mass Flux Differences for Opposite Flow Directions of a Condensable Gas through an Asymmetric Porous Membrane

    Czech Academy of Sciences Publication Activity Database

    Uchytil, Petr; Loimer, T.

    2014-01-01

    Roč. 470, NOV 15 (2014), s. 451-457 ISSN 0376-7388 R&D Projects: GA MŠk 7AMB12AT010; GA MŠk(CZ) 7AMB14AT011 Institutional support: RVO:67985858 Keywords : condensation * vapor permeation * asymmetric membrane s Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 5.056, year: 2014

  9. The lipidomes of vesicular stomatitis virus, semliki forest virus, and the host plasma membrane analyzed by quantitative shotgun mass spectrometry

    DEFF Research Database (Denmark)

    Kalvodova, Lucie; Sampaio, Julio L; Cordo, Sandra

    2009-01-01

    kidney cells can be infected by two different viruses, namely, vesicular stomatitis virus and Semliki Forest virus, from the Rhabdoviridae and Togaviridae families, respectively. We purified the host plasma membrane and the two different viruses after exit from the host cells and analyzed the lipid...

  10. Accessibility Changes within Diphtheria Toxin T Domain upon Membrane Penetration Probed by Hydrogen Exchange and Mass Spectrometry

    Czech Academy of Sciences Publication Activity Database

    Man, Petr; Montagner, C.; Vitrac, H.; Kavan, Daniel; Pichard, S.; Gillet, D.; Forest, E.; Forge, V.

    2011-01-01

    Roč. 414, č. 1 (2011), s. 123-134 ISSN 0022-2836 Institutional research plan: CEZ:AV0Z50200510 Keywords : diphtheria toxin * translocation domain * protein/membrane interactions Subject RIV: CE - Biochemistry Impact factor: 4.001, year: 2011

  11. Low frequency acoustic properties of bilayer membrane acoustic metamaterial with magnetic oscillator

    Directory of Open Access Journals (Sweden)

    Nansha Gao

    2017-07-01

    Full Text Available A bilayer membrane acoustic metamaterial was proposed to overcome the influence of the mass law on traditional acoustic materials and obtain a lightweight thin-layer structure that can effectively isolate low frequency noise. The finite element analysis (FEA results agree well with the experimental results. It is proved that the sound transmission losses (STLs of the proposed structures are higher than those of same surface density acoustic materials. The introduction of the magnetic mass block is different from the traditional design method, in which only a passive mass block is fixed on the membrane. The magnetic force will cause tension in the membrane, increase membrane prestress, and improve overall structural stiffness. The effects of the geometry size on the STLs are discussed in detail. The kind of method presented in this paper can provide a new means for engineering noise control. Keywords: Bilayer membrane acoustic metamaterial, Low frequency sound insulation, Sound transmission loss, Magnet oscillator

  12. Efficacy and compatibility with mass spectrometry of methods for elution of proteins from sodium dodecyl sulfate-polyacrylamide gels and polyvinyldifluoride membranes

    DEFF Research Database (Denmark)

    Jørgensen, C.S.; Jagd, M.; Sørensen, B.K.

    2004-01-01

    projects. As a result of this, methods for postelectrophoretic protein characterization are of Great interest as exemplified by in situ protease digestion combined with mass spectrometry (MS), which is the method of choice for identification of proteins. In this study we have developed and compared methods...... for recovering intact proteins from polyacrylamide gels and electroblotting membranes to define efficient methods compatible with MS. These methods complement in situ digestion protocols and allow determination of the molecular mass of whole proteins separated by SDS-PAGE. Passive elution of proteins from SDS......-PAGE gels was efficient only in the presence of SDS, whereas electroelution was achieved using butTers without SDS. Surface-enhanced laser desorption/ionization MS (SELDI-MS) analysis of proteins eluted in the presence of SIDS was possible using ion exchange ProteinChip arrays for concentration of sample...

  13. Microporous hollow fibre membrane modules as gas-liquid contactors. Part 2. Mass transfer with chemical reaction

    NARCIS (Netherlands)

    Kreulen, H.; Versteeg, G.F.; Swaaij, W.P.M. van

    1993-01-01

    Absorption determined by mass transfer in the liquid is described well with the Graetz-Lévèque equation adapted from heat transfer. The influence of a chemical reaction on the mass transfer was simulated with a numerical model and tested on the absorption of CO2 in a hydroxide solution. Absorption

  14. Efficacy of bacterial bioremediation: Demonstration of complete incorporation of hydrocarbons into membrane phospholipids from Rhodococcus hydrocarbon degrading bacteria by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, R.P.; Blumer, E.N.; Emmett, M.R.; Marshall, A.G.

    2000-02-01

    The authors present a method and example to establish complete incorporation of hydrocarbons into membrane phospholipids of putatively bioremediative bacteria. Bacteria are grown on minimal media containing a specified carbon source, either natural abundance or enriched. After extraction (but no other prior separation) of the membrane lipids, electrospray ionization yields a negative-ion FT-ICR mass spectrum containing prominent phospholipid parent ions. If {sup 13}C-enriched hydrocarbon incorporation is complete, then the mass of the parent ion will increase by n Da, in which n is the number of its constituent carbon atoms; moreover, the {sup 13}C isotopic distribution pattern will be reversed. The identities of the constituent fatty acids and polar headgroup are obtained by collisional dissociation (MS/MS), and their extent of {sup 13}C incorporation determined individually. The method is demonstrated for Rhodococcus rhodochrous (ATCC No. 53968), for which all 44 carbons of a representative phosphatidylinositol are shown to derive from the hydrocarbon source. Interestingly, although only C{sub 16} and C{sub 18} alkanes are provided in the growth medium, the bacteria synthesize uniformly enriched C16:0 and C19:0 fatty acids.

  15. Assessment of Mass Transfer Coefficients in Coalescing Slug Flow in Vertical Pipes and Applications to Tubular Airlift Membrane Bioreactors

    DEFF Research Database (Denmark)

    Ratkovich, Nicolas Rios; Berube, P.R.; Nopens, I.

    2011-01-01

    by the gas flow. It was noted that coalescence of bubbles affects the MTH. Coalescence increased the “width” of the peaks (i.e. the estimate of the variability of the mass transfer coefficient) and the height of the peak (i.e. amount of time that a mass transfer coefficient of a given value is maintained......). A semi-empirical relationship based on the Lévêque relationship for the Sherwood number (mass transfer coefficient) was formulated for the laminar regime. A test case comparison between water and activated sludge was performed based on full-scale airlift MBR operational conditions. It was found...

  16. A micro-fluidic sub-microliter sample introduction system for direct analysis of Chinese rice wine by inductively coupled plasma mass spectrometry using external aqueous calibration

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Heyong [Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou, 310027 (China); College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, 310036 (China); Liu, Jinhua [College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, 310036 (China); Xu, Zigang [Institute of Analytical and Applied Chemistry, Department of Chemistry, Zhejiang University, Hangzhou, 310027 (China); Yin, Xuefeng, E-mail: yinxf@zju.edu.cn [Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou, 310027 (China); College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, 310036 (China)

    2012-07-15

    A microfluidic sub-microliter sample introducing system was developed for direct analysis of Chinese rice wine by inductively coupled plasma mass spectrometry (ICP-MS). It consisted of a microfluidic chip integrating variable-volume sampling channels (0.1-0.8 {mu}L), an eight-way multi-functional valve used in flow injection analysis (FIA), a syringe pump and a peristaltic pump of the Ar ICP-MS instrument. Three solutions, i.e., 15, 40 and 100 g L{sup -1} glucose in 20% ethanol were used to simulate Chinese rice wine of the dry type, the semidry type and the semisweet type, each. The effects of their volume introduced into ICP-MS on the plasma stability and ICP-MS intensities were studied. The experimental results showed that neither alteration of plasma stability nor carbon deposition was observed when the sampling volume of 20% ethanol containing 100 g L{sup -1} glucose was downscaled to 0.8 {mu}L. Further reducing the sampling volume to 0.4 {mu}L, no significant difference between the intensities of multi-element standard prepared in three simulated Chinese rice wine matrices and those in aqueous solution was observed. It indicated no negative effect of Chinese rice wine matrix on the ICP-MS intensities. A sampling volume of 0.4 {mu}L was considered to be a good compromise between sensitivity and matrix effect. The flow rate of the carrier was chosen as 20 {mu}L min{sup -1} for obtaining peaks with the highest peak height within the shortest time. Based on these observations, a microflow injection ({mu}FI) method for the direct determination of cadmium and lead in Chinese rice wine by ICP-MS using an external aqueous calibration was developed. The sample throughput was 45 h{sup -1} with the detection limit of 19.8 and 10.4 ng L{sup -1} for Cd and Pb, respectively. The contents of Cd and Pb in 10 Chinese rice wine samples were measured. The results agreed well with those determined by ICP-MS with the conventional sampling system after microwave assisted digestion

  17. A micro-fluidic sub-microliter sample introduction system for direct analysis of Chinese rice wine by inductively coupled plasma mass spectrometry using external aqueous calibration

    International Nuclear Information System (INIS)

    Cheng, Heyong; Liu, Jinhua; Xu, Zigang; Yin, Xuefeng

    2012-01-01

    A microfluidic sub-microliter sample introducing system was developed for direct analysis of Chinese rice wine by inductively coupled plasma mass spectrometry (ICP-MS). It consisted of a microfluidic chip integrating variable-volume sampling channels (0.1–0.8 μL), an eight-way multi-functional valve used in flow injection analysis (FIA), a syringe pump and a peristaltic pump of the Ar ICP-MS instrument. Three solutions, i.e., 15, 40 and 100 g L −1 glucose in 20% ethanol were used to simulate Chinese rice wine of the dry type, the semidry type and the semisweet type, each. The effects of their volume introduced into ICP-MS on the plasma stability and ICP-MS intensities were studied. The experimental results showed that neither alteration of plasma stability nor carbon deposition was observed when the sampling volume of 20% ethanol containing 100 g L −1 glucose was downscaled to 0.8 μL. Further reducing the sampling volume to 0.4 μL, no significant difference between the intensities of multi-element standard prepared in three simulated Chinese rice wine matrices and those in aqueous solution was observed. It indicated no negative effect of Chinese rice wine matrix on the ICP-MS intensities. A sampling volume of 0.4 μL was considered to be a good compromise between sensitivity and matrix effect. The flow rate of the carrier was chosen as 20 μL min −1 for obtaining peaks with the highest peak height within the shortest time. Based on these observations, a microflow injection (μFI) method for the direct determination of cadmium and lead in Chinese rice wine by ICP-MS using an external aqueous calibration was developed. The sample throughput was 45 h −1 with the detection limit of 19.8 and 10.4 ng L −1 for Cd and Pb, respectively. The contents of Cd and Pb in 10 Chinese rice wine samples were measured. The results agreed well with those determined by ICP-MS with the conventional sampling system after microwave assisted digestion. The recoveries of three

  18. ADAMS - Introduction

    International Nuclear Information System (INIS)

    Song, Cheol Gi

    2003-06-01

    This book introduces ADAMS, which is composed of 20 modules ; stamping mechanism, ADAMS introduction, GUI overview failing stone project motion one DOF pendulum inclined plane lift mechanism I mechanism II mechanism III suspension subsystem suspension-steering system spring-damper I spring-damper II hatchback I hatchback II hatchback III cam-rocker-valve target practice recommended practice and switch mechanism workshop.

  19. Introduction; Vvedenie

    Energy Technology Data Exchange (ETDEWEB)

    Nikitin, V I

    1961-07-01

    Introduction describes the present book. Its includes seven chapters. First four from them touch with glycerin of acetylene line-their receiving, studying their oxidation reactions, transformations under the influence of dehydrating methods. Last three chapters dedicated to glycerin of ethylen line-synthesis, their cyclization into substituted dihydropyran.

  20. Bubble coalescence suppression driven carbon monoxide (CO)-water mass transfer increase by electrolyte addition in a hollow fiber membrane bioreactor (HFMBR) for microbial CO conversion to ethanol.

    Science.gov (United States)

    Jang, Nulee; Yasin, Muhammad; Kang, Hyunsoo; Lee, Yeubin; Park, Gwon Woo; Park, Shinyoung; Chang, In Seop

    2018-05-04

    This study investigated the effects of electrolytes (CaCl 2 , K 2 HPO 4 , MgSO 4 , NaCl, and NH 4 Cl) on CO mass transfer and ethanol production in a HFMBR. The hollow fiber membranes (HFM) were found to generate tiny gas bubbles; the bubble coalescence was significantly suppressed in electrolyte solution. The volumetric gas-liquid mass transfer coefficients (k L a) increased up to 414% compared to the control. Saturated CO (C ∗ ) decreased as electrolyte concentrations increased. Overall, the maximum mass transfer rate (R max ) in electrolyte solution ranged from 106% to 339% of the value obtained in water. The electrolyte toxicity on cell growth was tested using Clostridium autoethanogenum. Most electrolytes, except for MgSO 4 , inhibited cell growth. The HFMBR operation using a medium containing 1% MgSO 4 achieved 119% ethanol production compared to that without electrolytes. Finally, a kinetic simulation using the parameters got from the 1% MgSO 4 medium predicted a higher ethanol production compared to the control. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Membrane Assisted Simultaneous Extraction and Derivatization with Triphenylphosphine of Elemental Sulfur in Arabian Crude Samples by Gas Chromatography/Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Ibrahim Al-Zahrani

    2015-01-01

    Full Text Available Determination of trace level elemental sulfur from crude oil samples is a tedious task. Recently, several gas chromatographic methods were reported in which selective triphenylphosphine derivatization of sulfur was used to form triphenylphosphine sulfide. Direct quantitation of elemental sulfur from crude oil requires an efficient sample preparation method. This paper describes how simultaneous extraction derivatization of elemental sulfur was performed for the first time using porous hollow fiber membrane. A thick (0.25 um pore size; 1550 μm wall thickness; and 5500 μm inner diameter hollow fiber membrane filled with triphenylphosphine (dissolved N-methylpyrrolidone is used as a solvent bar. The solvent bar is tumbled freely in the crude oil sample; the elemental sulfur was extracted and derivatized. Finally, the derivatized sulfur was analyzed by gas chromatography/mass spectrometry. Various experimental conditions of solvent bar microextraction (SBME were optimized to achieve higher extraction. The linear range was established between 1 and 50 μg/mL, while a squared regression coefficient was found to be 0.9959 μg/mL. Relative standard deviation (RSD was below 10%. Relative recoveries were calculated for SBME in crude oil samples and were in the range between 98.2% and 101.2%.

  2. Analysis of polycyclic aromatic hydrocarbons in water and beverages using membrane-assisted solvent extraction in combination with large volume injection-gas chromatography-mass spectrometric detection.

    Science.gov (United States)

    Rodil, Rosario; Schellin, Manuela; Popp, Peter

    2007-09-07

    Membrane-assisted solvent extraction (MASE) in combination with large volume injection-gas chromatography-mass spectrometry (LVI-GC-MS) was applied for the determination of 16 polycyclic aromatic hydrocarbons (PAHs) in aqueous samples. The MASE conditions were optimized for achieving high enrichment of the analytes from aqueous samples, in terms of extraction conditions (shaking speed, extraction temperature and time), extraction solvent and composition (ionic strength, sample pH and presence of organic solvent). Parameters like linearity and reproducibility of the procedure were determined. The extraction efficiency was above 65% for all the analytes and the relative standard deviation (RSD) for five consecutive extractions ranged from 6 to 18%. At optimized conditions detection limits at the ng/L level were achieved. The effectiveness of the method was tested by analyzing real samples, such as river water, apple juice, red wine and milk.

  3. Gas-Phase Mass-Transfer Resistances at Polymeric Electrolyte Membrane Fuel Cells Electrodes: Theoretical Analysis on the Effectiveness of Interdigitated and Serpentine Flow Arrangements

    Directory of Open Access Journals (Sweden)

    Elisabetta Arato

    2016-03-01

    Full Text Available Mass transfer phenomena in polymeric electrolyte membrane fuel cells (PEMFC electrodes has already been analyzed in terms of the interactions between diffusive and forced flows. It was demonstrated that the whole phenomenon could be summarized by expressing the Sherwood number as a function of the Peclet number. The dependence of Sherwood number on Peclet one Sh(Pe function, which was initially deduced by determining three different flow regimes, has now been given a more accurate description. A comparison between the approximate and the accurate results for a reference condition of diluted reactant and limit current has shown that the former are useful for rapid, preliminary calculations. However, a more precise and reliable estimation of the Sherwood number is worth attention, as it provides a detailed description of the electrochemical kinetics and allows a reliable comparison of the various geometrical arrangements used for the distribution of the reactants.

  4. Fusion: introduction

    International Nuclear Information System (INIS)

    Decreton, M.

    2006-01-01

    The article gives an overview and introduction to the activities of SCK-CEN's research programme on fusion. The decision to construct the ITER international nuclear fusion experiment in Cadarache is highlighted. A summary of the Belgian contributions to fusion research is given with particular emphasis on studies of radiation effects on diagnostics systems, radiation effects on remote handling sensing systems, fusion waste management and socio-economic studies

  5. Osteoblast cell membrane chromatography coupled with liquid chromatography and time-of-flight mass spectrometry for screening specific active components from traditional Chinese medicines.

    Science.gov (United States)

    Wang, Nani; Zhang, Qiaoyan; Xin, Hailiang; Shou, Dan; Qin, Luping

    2017-11-01

    A method using osteoblast membrane chromatography coupled with liquid chromatography and time-of-flight mass spectrometry was developed to recognize and identify the specific active components from traditional Chinese medicines. Primary rat osteoblasts were used for the preparation of the stationary phase in the cell chromatography method. Retention components from the cell chromatography were collected and analyzed by liquid chromatography with time-of-flight mass spectrometry. This method was applied in screening active components from extracts of four traditional Chinese medicines. In total, 24 potentially active components with different structures were retained by osteoblast cell chromatography. There were five phenolic glucosides and one triterpenoid saponin from Curculigo orchioides Gaertn, two organic acids and ten flavonoids from Epimedium sagittatum Maxim, one phthalide compound and one organic acid from Angelica sinensis Diels, and two flavonoids and two saponins from Anemarrhena asphodeloides Bunge. Among those, four components (icariin, curculigoside, ferulaic acid, and timosaponin BII) were used for in vitro pharmacodynamics validation. They significantly increased the osteoblast proliferation, alkaline phosphatase activity, levels of bone gla protein and collagen type 1, and promoted mineralized nodule formation. The developed method was an effective screening method for finding active components from complex medicines that act on bone diseases. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Chapter 1. Introduction. Recommendations and standard operating procedures for intensive care unit and hospital preparations for an influenza epidemic or mass disaster

    NARCIS (Netherlands)

    Sprung, Charles L.; Cohen, Robert; Adini, Bruria; Christian, Michael D.; Camargo, Ruben; Ceraso, Daniel; Azoulay, Elie; Duguet, Alexandre; Guery, Benoit; Reinhart, Konrad; Barlavie, Yaron; Benin-Goren, Odeda; Klein, Motti; Leoniv, Yuval; Margalit, Gila; Rubinovitch, Bina; Sonnenblick, Moshe; Steinberg, Avraham; Weissman, Charles; Wolff, Donna; Kesecioglu, Jozef; de Jong, Menno; Moreno, Rui; An, Youzhong; Du, Bin; Joynt, Gavin M.; Colvin, John; Loo, Shi; Richards, Guy; Artigas, Antonio; Pugin, Jerome; Amundson, Dennis; Devereaux, Asha; Beigel, John; Danis, Marion; Farmer, Chris; Hick, John L.; Maki, Dennis; Masur, Henry; Rubinson, Lewis; Sandrock, Christian; Talmor, Daniel; Truong, Robert; Zimmerman, Janice; Brett, Steve; Montgomery, Hugh; Rhodes, Andrew; Sanderson, Frances; Taylor, Bruce; Monrgomery, Hugh

    2010-01-01

    In December 2007, the European Society of Intensive Care Medicine established a Task Force to develop standard operating procedures (SOPs) for operating intensive care units (ICU) during an influenza epidemic or mass disaster. To provide direction for health care professionals in the preparation and

  7. Structure and physical properties of bio membranes and model membranes

    International Nuclear Information System (INIS)

    Tibor Hianik

    2006-01-01

    Bio membranes belong to the most important structures of the cell and the cell organelles. They play not only structural role of the barrier separating the external and internal part of the membrane but contain also various functional molecules, like receptors, ionic channels, carriers and enzymes. The cell membrane also preserves non-equilibrium state in a cell which is crucial for maintaining its excitability and other signaling functions. The growing interest to the bio membranes is also due to their unique physical properties. From physical point of view the bio membranes, that are composed of lipid bilayer into which are incorporated integral proteins and on their surface are anchored peripheral proteins and polysaccharides, represent liquid s crystal of smectic type. The bio membranes are characterized by anisotropy of structural and physical properties. The complex structure of bio membranes makes the study of their physical properties rather difficult. Therefore several model systems that mimic the structure of bio membranes were developed. Among them the lipid monolayers at an air-water interphase, bilayer lipid membranes, supported bilayer lipid membranes and liposomes are most known. This work is focused on the introduction into the physical word of the bio membranes and their models. After introduction to the membrane structure and the history of its establishment, the physical properties of the bio membranes and their models are stepwise presented. The most focus is on the properties of lipid monolayers, bilayer lipid membranes, supported bilayer lipid membranes and liposomes that were most detailed studied. This lecture has tutorial character that may be useful for undergraduate and graduate students in the area of biophysics, biochemistry, molecular biology and bioengineering, however it contains also original work of the author and his co-worker and PhD students, that may be useful also for specialists working in the field of bio membranes and model

  8. A novel membrane inlet mass spectrometer method to measure ¹⁵NH4₄⁺ for isotope-enrichment experiments in aquatic ecosystems.

    Science.gov (United States)

    Yin, Guoyu; Hou, Lijun; Liu, Min; Liu, Zhanfei; Gardner, Wayne S

    2014-08-19

    Nitrogen (N) pollution in aquatic ecosystems has attracted much attention over the past decades, but the dynamics of this bioreactive element are difficult to measure in aquatic oxygen-transition environments. Nitrogen-transformation experiments often require measurement of (15)N-ammonium ((15)NH4(+)) ratios in small-volume (15)N-enriched samples. Published methods to determine N isotope ratios of dissolved ammonium require large samples and/or costly equipment and effort. We present a novel ("OX/MIMS") method to determine N isotope ratios for (15)NH4(+) in experimental waters previously enriched with (15)N compounds. Dissolved reduced (15)N (dominated by (15)NH4(+)) is oxidized with hypobromite iodine to nitrogen gas ((29)N2 and/or (30)N2) and analyzed by membrane inlet mass spectrometry (MIMS) to quantify (15)NH4(+) concentrations. The N isotope ratios, obtained by comparing the (15)NH4(+) to total ammonium (via autoanalyzer) concentrations, are compared to the ratios of prepared standards. The OX/MIMS method requires only small sample volumes of water (ca. 12 mL) or sediment slurries and is rapid, convenient, accurate, and precise (R(2) = 0.9994, p < 0.0001) over a range of salinities and (15)N/(14)N ratios. It can provide data needed to quantify rates of ammonium regeneration, potential ammonium uptake, and dissimilatory nitrate reduction to ammonium (DNRA). Isotope ratio results agreed closely (R = 0.998, P = 0.001) with those determined independently by isotope ratio mass spectrometry for DNRA measurements or by ammonium isotope retention time shift liquid chromatography for water-column N-cycling experiments. Application of OX/MIMS should simplify experimental approaches and improve understanding of N-cycling rates and fate in a variety of freshwater and marine environments.

  9. Membrane dynamics

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    Current topics include membrane-protein interactions with regard to membrane deformation or curvature sensing by BAR domains. Also, we study the dynamics of membrane tubes of both cells and simple model membrane tubes. Finally, we study membrane phase behavior which has important implications...... for the lateral organization of membranes as wells as for physical properties like bending, permeability and elasticity...

  10. Competing intermolecular interactions of artemisinin-type agents and aspirin with membrane phospholipids: Combined model mass spectrometry and quantum-chemical study

    Energy Technology Data Exchange (ETDEWEB)

    Pashynska, Vlada, E-mail: vlada@vl.kharkov.ua [B.Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine, Lenin Ave., 47, 61103 Kharkov (Ukraine); Stepanian, Stepan [B.Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine, Lenin Ave., 47, 61103 Kharkov (Ukraine); Gömöry, Agnes; Vekey, Karoly [Institute of Organic Chemistry of Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Magyar tudosok korutja, 2, Budapest H-1117 (Hungary); Adamowicz, Ludwik [University of Arizona, Department of Chemistry and Biochemistry, Tucson, AZ 85721 (United States)

    2015-07-09

    Highlights: • Competitive binding of artemisinin agents and aspirin with phospholipids is shown. • Complexation between the antimalarial drugs and aspirin molecules is also found. • Energetically favorable structures of the model complexes are identified by DFT. • Membranotropic activity of the studied drugs can be modified under joint usage. - Abstract: Study of intermolecular interactions of antimalarial artemisinin-type drugs and aspirin with membrane phospholipids is important in term of elucidation of the drugs activity modification under their joint usage. Combined experimental and computational study of the interaction of dihydroartemisinin, α-artemether, and artesunate with aspirin (ASP) and dipalmitoylphosphatidylcholine (DPPC) is performed by electrospray ionization (ESI) mass spectrometry and by DFT B3LYP/aug-cc-pVDZ methods. The results of the ESI investigation of systems containing artemisinin-type agent, ASP and DPPC, reveal a competition between the antimalarial agents and ASP for binding with DPPC molecules. The complexation between the antimalarial drugs and ASP is also found. Observed phenomena suggest that membranotropic activity of artemisin-type agents and aspirin is modified under their combined usage. To elucidate structure-energy characteristics of the non-covalent complexes studied the model DFT calculations are performed for dihydroartemisinin · ASP complex and complexes of the each drug with phosphatidylcholine head of DPPC in neutral and cationized forms.

  11. Competing intermolecular interactions of artemisinin-type agents and aspirin with membrane phospholipids: Combined model mass spectrometry and quantum-chemical study

    International Nuclear Information System (INIS)

    Pashynska, Vlada; Stepanian, Stepan; Gömöry, Agnes; Vekey, Karoly; Adamowicz, Ludwik

    2015-01-01

    Highlights: • Competitive binding of artemisinin agents and aspirin with phospholipids is shown. • Complexation between the antimalarial drugs and aspirin molecules is also found. • Energetically favorable structures of the model complexes are identified by DFT. • Membranotropic activity of the studied drugs can be modified under joint usage. - Abstract: Study of intermolecular interactions of antimalarial artemisinin-type drugs and aspirin with membrane phospholipids is important in term of elucidation of the drugs activity modification under their joint usage. Combined experimental and computational study of the interaction of dihydroartemisinin, α-artemether, and artesunate with aspirin (ASP) and dipalmitoylphosphatidylcholine (DPPC) is performed by electrospray ionization (ESI) mass spectrometry and by DFT B3LYP/aug-cc-pVDZ methods. The results of the ESI investigation of systems containing artemisinin-type agent, ASP and DPPC, reveal a competition between the antimalarial agents and ASP for binding with DPPC molecules. The complexation between the antimalarial drugs and ASP is also found. Observed phenomena suggest that membranotropic activity of artemisin-type agents and aspirin is modified under their combined usage. To elucidate structure-energy characteristics of the non-covalent complexes studied the model DFT calculations are performed for dihydroartemisinin · ASP complex and complexes of the each drug with phosphatidylcholine head of DPPC in neutral and cationized forms

  12. On-line monitoring of CO2 production in Lactococcus lactis during physiological pH decrease using membrane inlet mass spectrometry with dynamic pH calibration.

    Science.gov (United States)

    Andersen, Ann Zahle; Lauritsen, Frants Roager; Olsen, Lars Folke

    2005-12-20

    Monitoring CO2 production in systems, where pH is changing with time is hampered by the chemical behavior and pH-dependent volatility of this compound. In this article, we present the first method where the concentration and production rate of dissolved CO2 can be monitored directly, continuously, and quantitatively under conditions where pH changes rapidly ( approximately 2 units in 15 min). The method corrects membrane inlet mass spectrometry (MIMS) measurements of CO2 for pH dependency using on-line pH analysis and an experimentally established calibration model. It is valid within the pH range of 3.5 to 7, despite pH-dependent calibration constants that vary in a non-linear fashion with more than a factor of 3 in this interval. The method made it possible to determine the carbon dioxide production during Lactococcus lactis fermentations, where pH drops up to 3 units during the fermentation. The accuracy was approximately 5%. We used the method to investigate the effect of initial extracellular pH on carbon dioxide production during anarobic glucose fermentation by non-growing Lactocoocus lactis and demonstrated that the carbon dioxide production rate increases considerably, when the initial pH was increased from 6 to 6.8. (c) 2005 Wiley Periodicals, Inc.

  13. Development of a method for in situ measurement of denitrification in aquifers using 15N tracer tests and membrane inlet mass spectrometry

    Science.gov (United States)

    Eschenbach, W.; Well, R.; Flessa, H.; Walther, W.; Duijnisveld, W. H. M.

    2009-04-01

    In NO3- contaminated aquifers containing reduced compounds like organic carbon or sulfides, denitrification is an intense process. Its characterization is of interest because NO3- consump-tion improves water quality and N2O production can cause emission of this greenhouse gas to the atmosphere. Spatial distribution of NO3- and N2 produced by denitrification in groundwa-ter (excess N2) reflects the NO3- input as well as cumulative denitrification during aquifer pas-sage. Reaction progress (RP) at a given location, i.e. the relative consumption by denitrifica-tion of the NO3- that had been leached to the aquifers, characterizes the stage of the denitrifi-cation process. RP can be derived from the ratio between accumulated gaseous denitrification products and initial NO3- concentrations. The amount and spatial distribution of reduced com-pounds within denitrifying aquifers is not well known. Recent findings from parallel investi-gations on in situ denitrification and reactive compounds suggests that single-well 15N tracer tests might be suitable to characterize the stock of reduced compounds in aquifers (Konrad 2007). The overall objective of our studies is measure the spatial dynamics of denitrification within two sandy aquifers in northern Germany. This includes measurement of the actually occurring denitrification process. Moreover we want to determine the long-term denitrification potential which is governed by the stock of reactive material. Here we present a new approach for in situ-measurement of denitrification at monitoring wells using a combination of 15N-tracer push-pull experiments with in situ analysis of 15N-labled N2 and N2O using membrane inlet mass spectrometry (MIMS). We will present first results from a laboratory test with aquifer mesocosms using the MIMS method. In this test we supplemented aquifer material of two depths (2 and 7 m below surface) of a drinking water catchment in Northwest Germany with K15NO3 solution. After tracer application we

  14. Introduction to Body Composition Assessment Using the Deuterium Dilution Technique with Analysis of Urine Samples by Isotope Ratio Mass Spectrometry (French Edition)

    International Nuclear Information System (INIS)

    2013-01-01

    The IAEA has fostered the more widespread use of a stable isotope technique to assess body composition in different population groups to address priority areas in public health nutrition in Member States. It has done this by supporting national and regional nutrition projects through its technical cooperation programme and coordinated research projects over many years. This publication was developed by an international group of experts to provide practical hands-on guidance in the use of this technique in settings where analysis of stable isotope ratios in biological samples is to be made by isotope ratio mass spectrometry. The publication is targeted at new users of this technique, for example nutritionists, analytical chemists and other professionals. More detailed information on the theoretical background and the practical applications of state of the art methodologies to monitor changes in body composition can be found in IAEA Human Health Series No. 3, Assessment of Body Composition and Total Energy Expenditure in Humans by Stable Isotope Techniques

  15. Introduction to Body Composition Assessment Using the Deuterium Dilution Technique with Analysis of Urine Samples by Isotope Ratio Mass Spectrometry (Spanish Edition)

    International Nuclear Information System (INIS)

    2013-01-01

    The IAEA has fostered the more widespread use of a stable isotope technique to assess body composition in different population groups to address priority areas in public health nutrition in Member States. It has done this by supporting national and regional nutrition projects through its technical cooperation programme and coordinated research projects over many years. This publication was developed by an international group of experts to provide practical hands-on guidance in the use of this technique in settings where analysis of stable isotope ratios in biological samples is to be made by isotope ratio mass spectrometry. The publication is targeted at new users of this technique, for example nutritionists, analytical chemists and other professionals. More detailed information on the theoretical background and the practical applications of state of the art methodologies to monitor changes in body composition can be found in IAEA Human Health Series No. 3, Assessment of Body Composition and Total Energy Expenditure in Humans by Stable Isotope Techniques

  16. Simple and accurate measurement of carbamazepine in surface water by use of porous membrane-protected micro-solid-phase extraction coupled with isotope dilution mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Teo, Hui Ling [Chemical Metrology Division, Applied Sciences Group, Health Sciences Authority, 1 Science Park Road, #01-05/06, The Capricorn, Singapore Science Park II, Singapore 117528 (Singapore); Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543 (Singapore); Wong, Lingkai [Chemical Metrology Division, Applied Sciences Group, Health Sciences Authority, 1 Science Park Road, #01-05/06, The Capricorn, Singapore Science Park II, Singapore 117528 (Singapore); Liu, Qinde, E-mail: liu_qinde@hsa.gov.sg [Chemical Metrology Division, Applied Sciences Group, Health Sciences Authority, 1 Science Park Road, #01-05/06, The Capricorn, Singapore Science Park II, Singapore 117528 (Singapore); Teo, Tang Lin; Lee, Tong Kooi [Chemical Metrology Division, Applied Sciences Group, Health Sciences Authority, 1 Science Park Road, #01-05/06, The Capricorn, Singapore Science Park II, Singapore 117528 (Singapore); Lee, Hian Kee, E-mail: chmleehk@nus.edu.sg [Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543 (Singapore)

    2016-03-17

    To achieve fast and accurate analysis of carbamazepine in surface water, we developed a novel porous membrane-protected micro-solid-phase extraction (μ-SPE) method, followed by liquid chromatography-isotope dilution tandem mass spectrometry (LC-IDMS/MS) analysis. The μ-SPE device (∼0.8 × 1 cm) was fabricated by heat-sealing edges of a polypropylene membrane sheet to devise a bag enclosing the sorbent. The analytes (both carbamazepine and isotope-labelled carbamazepine) were first extracted by μ-SPE device in the sample (10 mL) via agitation, then desorbed in an organic solvent (1 mL) via ultrasonication. Several parameters such as organic solvent for pre-conditioning of μ-SPE device, amount of sorbent, adsorption time, and desorption solvent and time were investigated to optimize the μ-SPE efficiency. The optimized method has limits of detection and quantitation estimated to be 0.5 ng L{sup −1} and 1.6 ng L{sup −1}, respectively. Surface water samples spiked with different amounts of carbamazepine (close to 20, 500, and 1600 ng L{sup −1}, respectively) were analysed for the validation of method precision and accuracy. Good precision was obtained as demonstrated by relative standard deviations of 0.7% for the samples with concentrations of 500 and 1600 ng kg{sup −1}, and 5.8% for the sample with concentration of 20 ng kg{sup −1}. Good accuracy was also demonstrated by the relative recoveries in the range of 96.7%–103.5% for all samples with uncertainties of 1.1%–5.4%. Owing to the same chemical properties of carbamazepine and isotope-labelled carbamazepine, the isotope ratio in the μ-SPE procedure was accurately controlled. The use of μ-SPE coupled with IDMS analysis significantly facilitated the fast and accurate measurement of carbamazepine in surface water. - Highlights: • μ-SPE coupled with IDMS for the measurement of carbamazepine. • The method is the first report of coupling μ-SPE with IDMS. • μ-SPE is fast, time

  17. Introduction Pages

    Directory of Open Access Journals (Sweden)

    Radu E. SESTRAS

    2018-03-01

    Full Text Available Notulae Scientia Biologicae (http://www.notulaebiologicae.ro, Issue 1, Volume 10, 2018: The papers published in this issue (http://www.notulaebiologicae.ro/index.php/nsb/issue/current represent interesting novelties in different topics of life science. Among the exciting researches, we invite you to find news about enhancing the resistance of watermelon; biodiversity within Mt. Hamiguitan Range Wildlife Sanctuary; bioactive compounds investigated in several species (Litsea glutinosa, Senna alata, etc.; new approaches for technical aspects for improving crops of interest (mass production of Spirulina, gamma radiation treatments on potato and sesame, testing banana peel as substrate; cytogenetic, forestry and carbon sequestration; reproductive behavior with significant embryological data. Notulae Scientia Biologicae journal has moved to online-only publication at the start of 2017. At the same time, we maintain our standard publication, as printed form, with 'classic' style - volume, issue, pagination.

  18. Introduction of a 20 kHz Nd:YVO4 laser into a hybrid quadrupole time-of-flight mass spectrometer for MALDI-MS imaging.

    Science.gov (United States)

    Trim, Paul J; Djidja, Marie-Claude; Atkinson, Sally J; Oakes, Keith; Cole, Laura M; Anderson, David M G; Hart, Philippa J; Francese, Simona; Clench, Malcolm R

    2010-08-01

    A commercial hybrid quadrupole time-of-flight mass spectrometer has been modified for high-speed matrix-assisted laser desorption ionisation (MALDI) imaging using a short-pulse optical technology Nd:YVO(4) laser. The laser operating in frequency-tripled mode (lambda = 355 nm) is capable of delivering 1.5-ns pulses of energy at up to 8 microJ at 5-10 kHz and 3 microJ at 20 kHz. Experiments to improve beam homogeneity and reduce laser speckle by mechanical vibration of the fibre-optic laser delivery system are reported along with data from trial and tissue imaging experiments using the modified instrument. The laser appeared to yield best results for MALDI-MS imaging experiments when operating at repetition rates 5-10 kHz. Combining this with raster imaging allowed images of rat brain sections to be recorded in 37 min. Similarly, images of the distribution of peptides in "on-tissue" digest experiments from tumour tissues were recorded in 1 h and 30 min rather than the 8-h acquisition time previously used. A brief investigation of targeted protein analysis/imaging by multiple reaction monitoring experiments "on-tissue" is reported. A total of 26 transitions were recorded over a 3-s cycle time and images of abundant proteins were successfully recorded.

  19. History and General Introduction

    International Nuclear Information System (INIS)

    Dunbar, R.C.

    1991-01-01

    In the domain of analytical mass spectrometry (MS), FT-ICR's place is established as combining particular advantages of extraordinary mass resolution and accuracy, a wide array of sample-ionization techniques, and a uniquely wide range of methods for structure characterization of the primary sample ions. Costs are already attractive compared with other high-performance alternatives, and as both magnets and computers (which comprise much of the expense of FT-ICR hardware) become cheaper and more powerful, the performance/cost ratio for the technique will continue to improve. This paper will provide an introduction to those who have little previous knowledge of the technique; provide an overview of the technique's outstanding areas of scientific and analytical application; and provide some historical perspective on how we reached the present state of the art

  20. Gas separation with membranes

    International Nuclear Information System (INIS)

    Schulz, G.; Michele, H.; Werner, U.

    1982-01-01

    Gas separation with membranes has already been tested in numerous fields of application, e.g. uranium enrichment of H 2 separation. In many of these processes the mass transfer units, so-called permeators, have to be connected in tandem in order to achieve high concentrations. A most economical operating method provides for each case an optimization of the cascades with regard to the membrane materials, construction and design of module. By utilization of the concentration gradient along the membrane a new process development has been accomplished - the continuously operating membrane rectification unit. Investment and operating costs can be reduced considerably for a number of separating processes by combining a membrane rectification unit with a conventional recycling cascade. However, the new procedure requires that the specifications for the module construction, flow design, and membrane properties be reconsidered. (orig.) [de

  1. Preparation and Properties of Nano-Hydroxyapatite/Gelatin/Poly(vinyl alcohol) Composite Membrane.

    Science.gov (United States)

    Liao, Haotian; Shi, Kun; Peng, Jinrong; Qu, Ying; Liao, Jinfeng; Qian, Zhiyong

    2015-06-01

    In this study, the bone-like composite membrane based on blends of gelatin (Gel), nano-hydroxyapatite (n-HA) and poly(vinyl alcohol) (PVA) was fabricated by solvent casting and evaporation methods. The effect of n-HA content and the ratio of Gel/PVA on the properties of the composite was investigated. The Gel/PVA and n-HA/Gel/PVA composite membranes were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), water contact angle measurement and scanning electron microscopy (SEM). The mechanical properties of the composites were determined by tensile tests. The as prepared composite membranes exhibited hydrophobility, the water contact angle of composite membrane was 126.6 when its mass ratio of n-HA/Gel/PVA was 10/50/40. The tensile strength of composite membranes was greatly increased due to the introduction of n-HA, and the tensile strength was increased to 74.92 MPa when the mass ratio of n-HA/Gel/PVA was 10/50/40. SEM observation indicated that n-HA was dispersed in the membranes and a sea-island structure was formed in the n-HA/Gel/PVA composite membranes, resulting in a significant increase in tensile strength. The as-prepared n-HA/Gel/PVA composite membranes may be applied in the field of bone tissue engineering.

  2. Atomistic Monte Carlo simulation of lipid membranes

    DEFF Research Database (Denmark)

    Wüstner, Daniel; Sklenar, Heinz

    2014-01-01

    Biological membranes are complex assemblies of many different molecules of which analysis demands a variety of experimental and computational approaches. In this article, we explain challenges and advantages of atomistic Monte Carlo (MC) simulation of lipid membranes. We provide an introduction...... of local-move MC methods in combination with molecular dynamics simulations, for example, for studying multi-component lipid membranes containing cholesterol....

  3. A mini-scale mass production and separation system for secretory heterologous proteins by perfusion culture of recombinant Pichia pastoris using a shaken ceramic membrane flask.

    Science.gov (United States)

    Ohashi, R; Mochizuki, E; Suzuki, T

    1999-01-01

    The perfusion culture technique using a shaken ceramic membrane flask (SCM flask) was applied to the production of a secretory heterologous protein. A recombinant methylotrophic yeast strain, Pichia pastoris, was cultured aerobically on a reciprocal shaker using an SCM flask. High-level production of human serum albumin (HSA) was attempted by increasing both the cell concentration and the expression level of the recombinant gene. In the two-stage culture method, the cell concentration was first raised to 17 g/l by feeding glycerol, after which the expression of HSA was induced by feeding methanol. However, the concentration of HSA in the effluent filtrate was as low as 0.15 g/l, while the cell concentration continued to increase. In contrast, HSA was effectively produced by feeding methanol from an early stage of the culture. In this case, the HSA concentration reached 0.24 and 0.46 g/l, respectively, using the growth-associated production method without and with aeration into the head space of the SCM flask. The results showed that supplying sufficient oxygen together with the growth-associated induction method are effective for obtaining high-level expression of the methanol-inducible recombinant gene of P. pastoris. An HSA concentration in the filtrate of 1.5 g/l was finally achieved when the cell concentration was increased to 53 g/l by supplying oxygen-enriched gas to the SCM flask. The yield and productivity of HSA reached 2.6-fold and 10-fold those obtained in an ordinary fed-batch culture using a shake flask, and these levels were readily achieved by continuous replenishment of the culture supernatant. The achievements made in this study should contribute to the development of a handy bioreactor system for mini-scale mass production of target proteins with separation at high purity.

  4. Introduction pages

    Directory of Open Access Journals (Sweden)

    Radu E. Sestras

    2015-09-01

    Full Text Available Introduction Pages and Table of Contents Research ArticlesInsulin Requirements in Relation to Insulin Pump Indications in Type 1 DiabetesPDFGabriela GHIMPEŢEANU,\tSilvia Ş. IANCU,\tGabriela ROMAN,\tAnca M. ALIONESCU259-263Comparative Antibacterial Efficacy of Vitellaria paradoxa (Shea Butter Tree Extracts Against Some Clinical Bacterial IsolatesPDFKamoldeen Abiodun AJIJOLAKEWU,\tFola Jose AWARUN264-268A Murine Effort Model for Studying the Influence of Trichinella on Muscular Activity of MicePDFIonut MARIAN,\tCălin Mircea GHERMAN,\tAndrei Daniel MIHALCA269-271Prevalence and Antibiogram of Generic Extended-Spectrum β-Lactam-Resistant Enterobacteria in Healthy PigsPDFIfeoma Chinyere UGWU,\tMadubuike Umunna ANYANWU,\tChidozie Clifford UGWU,\tOgbonna Wilfred UGWUANYI272-280Index of Relative Importance of the Dietary Proportions of Sloth Bear (Melursus ursinus in Semi-Arid RegionPDFTana P. MEWADA281-288Bioaccumulation Potentials of Momordica charantia L. Medicinal Plant Grown in Lead Polluted Soil under Organic Fertilizer AmendmentPDFOjo Michael OSENI,\tOmotola Esther DADA,\tAdekunle Ajayi ADELUSI289-294Induced Chitinase and Chitosanase Activities in Turmeric Plants by Application of β-D-Glucan NanoparticlesPDFSathiyanarayanan ANUSUYA,\tMuthukrishnan SATHIYABAMA295-298Present or Absent? About a Threatened Fern, Asplenium adulterinum Milde, in South-Eastern Carpathians (RomaniaPDFAttila BARTÓK,\tIrina IRIMIA299-307Comparative Root and Stem Anatomy of Four Rare Onobrychis Mill. (Fabaceae Taxa Endemic in TurkeyPDFMehmet TEKİN,\tGülden YILMAZ308-312Propagation of Threatened Nepenthes khasiana: Methods and PrecautionsPDFJibankumar S. KHURAIJAM,\tRup K. ROY313-315Alleviate Seed Ageing Effects in Silybum marianum by Application of Hormone Seed PrimingPDFSeyed Ata SIADAT,\tSeyed Amir MOOSAVI,\tMehran SHARAFIZADEH316-321The Effect of Halopriming and Salicylic Acid on the Germination of Fenugreek (Trigonella foenum-graecum under Different Cadmium

  5. A micro-fluidic sub-microliter sample introduction system for direct analysis of Chinese rice wine by inductively coupled plasma mass spectrometry using external aqueous calibration

    Science.gov (United States)

    Cheng, Heyong; Liu, Jinhua; Xu, Zigang; Yin, Xuefeng

    2012-07-01

    A microfluidic sub-microliter sample introducing system was developed for direct analysis of Chinese rice wine by inductively coupled plasma mass spectrometry (ICP-MS). It consisted of a microfluidic chip integrating variable-volume sampling channels (0.1-0.8 μL), an eight-way multi-functional valve used in flow injection analysis (FIA), a syringe pump and a peristaltic pump of the Ar ICP-MS instrument. Three solutions, i.e., 15, 40 and 100 g L- 1 glucose in 20% ethanol were used to simulate Chinese rice wine of the dry type, the semidry type and the semisweet type, each. The effects of their volume introduced into ICP-MS on the plasma stability and ICP-MS intensities were studied. The experimental results showed that neither alteration of plasma stability nor carbon deposition was observed when the sampling volume of 20% ethanol containing 100 g L- 1 glucose was downscaled to 0.8 μL. Further reducing the sampling volume to 0.4 μL, no significant difference between the intensities of multi-element standard prepared in three simulated Chinese rice wine matrices and those in aqueous solution was observed. It indicated no negative effect of Chinese rice wine matrix on the ICP-MS intensities. A sampling volume of 0.4 μL was considered to be a good compromise between sensitivity and matrix effect. The flow rate of the carrier was chosen as 20 μL min- 1 for obtaining peaks with the highest peak height within the shortest time. Based on these observations, a microflow injection (μFI) method for the direct determination of cadmium and lead in Chinese rice wine by ICP-MS using an external aqueous calibration was developed. The sample throughput was 45 h- 1 with the detection limit of 19.8 and 10.4 ng L- 1 for Cd and Pb, respectively. The contents of Cd and Pb in 10 Chinese rice wine samples were measured. The results agreed well with those determined by ICP-MS with the conventional sampling system after microwave assisted digestion. The recoveries of three Chinese

  6. Analytical evaluation of nebulizers for the introduction of acetic acid extracts aiming at the determination of trace elements by inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Gois, Jefferson S. de; Maranhao, Tatiane de A. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-970, Florianopolis, SC (Brazil); Oliveira, Fernando J.S. [Petroleo Brasileiro S.A., Gerencia de Meio Ambiente, Rio de Janeiro, RJ (Brazil); Frescura, Vera L.A.; Curtius, Adilson J. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-970, Florianopolis, SC (Brazil); Borges, Daniel L.G., E-mail: daniel.borges@ufsc.br [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-970, Florianopolis, SC (Brazil)

    2012-11-15

    Most of the official procedures aiming at classification of solid waste toxicity take into account metal solubility and bioavailability by means of extraction experiments using acetic acid solutions. Hence, the aim of this work was to investigate and optimize conditions to suppress the effect of acetic acid on the determination of trace elements using inductively coupled plasma mass spectrometry. The performance of four nebulizers (cross-flow (CFN), ultrasonic (USN), Meinhard (MN) and MicroMist (MMN)) were compared as to their efficiency in minimizing spectral and non-spectral effects on the determination of Ag, As, Ba, Cd, Cr, Hg, Pb and Se, with the ultimate goal to analyze acetic acid extracts obtained from solid waste residues. Operating conditions (desolvation temperatures for USN, RF power and nebulizer gas flow rates) were optimized individually for each nebulizer and for all analytes maintained in 0.14 mol L{sup -1} HNO{sub 3} solutions and in solutions prepared with acetic acid and acetic acid + NaOH, adjusted to pH 2.88 and 4.93, respectively. Pronounced non-spectral interferences for {sup 75}As and {sup 82}Se were observed in the presence of acetic acid for CF and MN, although to a less extent also for MMN and USN. Signal increase for blank solutions measured at m/z 208 ({sup 208}Pb) for CFN and MN, 107 ({sup 107}Ag) for USN and MN coupled to a cyclonic chamber and, m/z 82 ({sup 82}Se) for USN was observed, indicating an increased risk of spectral interference upon an increase in the concentration of acetic acid. Signal increase at specific m/z ratios, however, was not significant when the MMN was used, with the exception of m/z 52 ({sup 52}Cr) in acetic acid solutions, arising from the formation of {sup 40}Ar{sup 12}C{sup +}. This same effect was noticed for all nebulizers, although at noticeably different intensities. A signal stability study was performed, demonstrating that variations in the analytical signal were within a 20% range for all analytes

  7. Membranes: A Variety of Energy Landscapes for Many Transfer Opportunities.

    Science.gov (United States)

    Bacchin, Patrice

    2018-02-22

    A membrane can be represented by an energy landscape that solutes or colloids must cross. A model accounting for the momentum and the mass balances in the membrane energy landscape establishes a new way of writing for the Darcy law. The counter-pressure in the Darcy law is no longer written as the result of an osmotic pressure difference but rather as a function of colloid-membrane interactions. The ability of the model to describe the physics of the filtration is discussed in detail. This model is solved in a simplified energy landscape to derive analytical relationships that describe the selectivity and the counter-pressure from ab initio operating conditions. The model shows that the stiffness of the energy landscape has an impact on the process efficiency: a gradual increase in interactions (such as with hourglass pore shape) can reduce the separation energetic cost. It allows the introduction of a new paradigm to increase membrane efficiency: the accumulation that is inherent to the separation must be distributed across the membrane. Asymmetric interactions thus lead to direction-dependent transfer properties and the membrane exhibits diode behavior. These new transfer opportunities are discussed.

  8. Comparative N-glycoproteomic and phosphoproteomic profiling of human placental plasma membrane between normal and preeclampsia pregnancies with high-resolution mass spectrometry.

    Directory of Open Access Journals (Sweden)

    Fuqiang Wang

    Full Text Available Preeclampsia is a serious complication of pregnancy, which affects 2-8% of all pregnancies and is one of the leading causes of maternal and perinatal mortality and morbidity worldwide. To better understand the molecular mechanisms involved in pathological development of placenta in preeclampsia, we used high-resolution LC-MS/MS technologies to construct a comparative N-glycoproteomic and phosphoproteomic profiling of human placental plasma membrane in normal and preeclamptic pregnancies. A total of 1027 N-glyco- and 2094 phospho- sites were detected in human placental plasma membrane, and 5 N-glyco- and 38 phospho- proteins, respectively, with differentially expression were definitively identified between control and preeclamptic placental plasma membrane. Further bioinformatics analysis indicated that these differentially expressed proteins correlate with several specific cellular processes occurring during pathological changes of preeclamptic placental plasma membrane.

  9. Quantitative transporter proteomics by liquid chromatography with tandem mass spectrometry: addressing methodologic issues of plasma membrane isolation and expression-activity relationship.

    Science.gov (United States)

    Kumar, Vineet; Prasad, Bhagwat; Patilea, Gabriela; Gupta, Anshul; Salphati, Laurent; Evers, Raymond; Hop, Cornelis E C A; Unadkat, Jashvant D

    2015-02-01

    To predict transporter-mediated drug disposition using physiologically based pharmacokinetic models, one approach is to measure transport activity and relate it to protein expression levels in cell lines (overexpressing the transporter) and then scale these to via in vitro to in vivo extrapolation (IVIVE). This approach makes two major assumptions. First, that the expression of the transporter is predominantly in the plasma membrane. Second, that there is a linear correlation between expression level and activity of the transporter protein. The present study was conducted to test these two assumptions. We evaluated two commercially available kits that claimed to separate plasma membrane from other cell membranes. The Qiagen Qproteome kit yielded very little protein in the fraction purported to be the plasma membrane. The Abcam Phase Separation kit enriched the plasma membrane but did not separate it from other intracellular membranes. For the Abcam method, the expression level of organic anion-transporting polypeptides (OATP) 1B1/2B1 and breast cancer resistance protein (BCRP) proteins in all subcellular fractions isolated from cells or human liver tissue tracked that of Na⁺-K⁺ ATPase. Assuming that Na⁺-K⁺ ATPase is predominantly located in the plasma membrane, these data suggest that the transporters measured are also primarily located in the plasma membrane. Using short hairpin RNA, we created clones of cell lines with varying degrees of OATP1B1 or BCRP expression level. In these clones, transport activity of OATP1B1 or BCRP was highly correlated with protein expression level (r² > 0.9). These data support the use of transporter expression level data and activity data from transporter overexpressing cell lines for IVIVE of transporter-mediated disposition of drugs. Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.

  10. Membrane fusion

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    At Stanford University, Boxer lab, I worked on membrane fusion of small unilamellar lipid vesicles to flat membranes tethered to glass surfaces. This geometry closely resembles biological systems in which liposomes fuse to plasma membranes. The fusion mechanism was studied using DNA zippering...... between complementary strands linked to the two apposing membranes closely mimicking the zippering mechanism of SNARE fusion complexes....

  11. Sample introduction systems for reversed phase LC-ICP-MS of selenium using large amounts of methanol - comparison of systems based on membrane desolvation, a spray chamber and direct injection

    DEFF Research Database (Denmark)

    Bendahl, L.; Gammelgaard, Bente

    2005-01-01

    nebuliser (MCN) in combination with a membrane desolvator ( MD), a MCN in combination with a cyclonic spray chamber ( CS) and a direct injection nebuliser ( DIN), respectively. Thirteen selenium standards diluted in 50% methanol were introduced in each system at a flow rate of 50 mu l min(-1). Except...

  12. Introduction to general relativity

    CERN Document Server

    Parthasarthy, R

    2016-01-01

    INTRODUCTION TO GENERAL RELATIVITY begins with a description of the geometry of curved space, explaining geodesics, parallel transport, covariant differentiation, geodesic deviation and spacetime symmetry by killing vectors. It then introduces Einstein's theory of gravitation followed by Schwarzschild solution with its relevance to Positive Mass theorem. The three tests for Einstein's gravity are explained. Other exact solutions such as Vaidya, Kerr and Reisner - Nordstrom metric are included. In the Chapter on cosmological solutions, a detailed description of Godel metric is provided. It then introduces five dimensional spacetime of Kaluza showing the unification of gravity with electromagnetism. This is extended to include non-Abelian gauge theory by invoking compact extra dimensions. Explicit expressions in this case for Christoffel connections and ricci tensor are derived and the higher dimensional gravity action is shown to compactification are given.

  13. Combining blue native polyacrylamide gel electrophoresis with liquid chromatography tandem mass spectrometry as an effective strategy for analyzing potential membrane protein complexes of Mycobacterium bovis bacillus Calmette-Guérin

    Directory of Open Access Journals (Sweden)

    Li Weijun

    2011-01-01

    Full Text Available Abstract Background Tuberculosis is an infectious bacterial disease in humans caused primarily by Mycobacterium tuberculosis, and infects one-third of the world's total population. Mycobacterium bovis bacillus Calmette-Guérin (BCG vaccine has been widely used to prevent tuberculosis worldwide since 1921. Membrane proteins play important roles in various cellular processes, and the protein-protein interactions involved in these processes may provide further information about molecular organization and cellular pathways. However, membrane proteins are notoriously under-represented by traditional two-dimensional polyacrylamide gel electrophoresis (2-D PAGE and little is known about mycobacterial membrane and membrane-associated protein complexes. Here we investigated M. bovis BCG by an alternative proteomic strategy coupling blue native PAGE to liquid chromatography tandem mass spectrometry (LC-MS/MS to characterize potential protein-protein interactions in membrane fractions. Results Using this approach, we analyzed native molecular composition of protein complexes in BCG membrane fractions. As a result, 40 proteins (including 12 integral membrane proteins, which were organized in 9 different gel bands, were unambiguous identified. The proteins identified have been experimentally confirmed using 2-D SDS PAGE. We identified MmpL8 and four neighboring proteins that were involved in lipid transport complexes, and all subunits of ATP synthase complex in their monomeric states. Two phenolpthiocerol synthases and three arabinosyltransferases belonging to individual operons were obtained in different gel bands. Furthermore, two giant multifunctional enzymes, Pks7 and Pks8, and four mycobacterial Hsp family members were determined. Additionally, seven ribosomal proteins involved in polyribosome complex and two subunits of the succinate dehydrogenase complex were also found. Notablely, some proteins with high hydrophobicity or multiple transmembrane

  14. Combining blue native polyacrylamide gel electrophoresis with liquid chromatography tandem mass spectrometry as an effective strategy for analyzing potential membrane protein complexes of Mycobacterium bovis bacillus Calmette-Guérin.

    Science.gov (United States)

    Zheng, Jianhua; Wei, Candong; Zhao, Lina; Liu, Liguo; Leng, Wenchuan; Li, Weijun; Jin, Qi

    2011-01-18

    Tuberculosis is an infectious bacterial disease in humans caused primarily by Mycobacterium tuberculosis, and infects one-third of the world's total population. Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccine has been widely used to prevent tuberculosis worldwide since 1921. Membrane proteins play important roles in various cellular processes, and the protein-protein interactions involved in these processes may provide further information about molecular organization and cellular pathways. However, membrane proteins are notoriously under-represented by traditional two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) and little is known about mycobacterial membrane and membrane-associated protein complexes. Here we investigated M. bovis BCG by an alternative proteomic strategy coupling blue native PAGE to liquid chromatography tandem mass spectrometry (LC-MS/MS) to characterize potential protein-protein interactions in membrane fractions. Using this approach, we analyzed native molecular composition of protein complexes in BCG membrane fractions. As a result, 40 proteins (including 12 integral membrane proteins), which were organized in 9 different gel bands, were unambiguous identified. The proteins identified have been experimentally confirmed using 2-D SDS PAGE. We identified MmpL8 and four neighboring proteins that were involved in lipid transport complexes, and all subunits of ATP synthase complex in their monomeric states. Two phenolpthiocerol synthases and three arabinosyltransferases belonging to individual operons were obtained in different gel bands. Furthermore, two giant multifunctional enzymes, Pks7 and Pks8, and four mycobacterial Hsp family members were determined. Additionally, seven ribosomal proteins involved in polyribosome complex and two subunits of the succinate dehydrogenase complex were also found. Notablely, some proteins with high hydrophobicity or multiple transmembrane helixes were identified well in our work. In this

  15. Determination of extremely low {sup 236}U/{sup 238}U isotope ratios in environmental samples by sector-field inductively coupled plasma mass spectrometry using high-efficiency sample introduction

    Energy Technology Data Exchange (ETDEWEB)

    Boulyga, Sergei F. [Institute of Inorganic Chemistry and Analytical Chemistry, Johannes Gutenberg-University Mainz, Duesbergweg 10-14, 55099 Mainz (Germany)]. E-mail: sergei.boulyga@univie.ac.at; Heumann, Klaus G. [Institute of Inorganic Chemistry and Analytical Chemistry, Johannes Gutenberg-University Mainz, Duesbergweg 10-14, 55099 Mainz (Germany)

    2006-07-01

    A method by inductively coupled plasma mass spectrometry (Icp-Ms) was developed which allows the measurement of {sup 236}U at concentration ranges down to 3 x 10{sup -14} g g{sup -1} and extremely low {sup 236}U/{sup 238}U isotope ratios in soil samples of 10{sup -7}. By using the high-efficiency solution introduction system APEX in connection with a sector-field ICP-MS a sensitivity of more than 5000 counts fg{sup -1} uranium was achieved. The use of an aerosol desolvating unit reduced the formation rate of uranium hydride ions UH{sup +}/U{sup +} down to a level of 10{sup -6}. An abundance sensitivity of 3 x 10{sup -7} was observed for {sup 236}U/{sup 238}U isotope ratio measurements at mass resolution 4000. The detection limit for {sup 236}U and the lowest detectable {sup 236}U/{sup 238}U isotope ratio were improved by more than two orders of magnitude compared with corresponding values by alpha spectrometry. Determination of uranium in soil samples collected in the vicinity of Chernobyl nuclear power plant (NPP) resulted in that the {sup 236}U/{sup 238}U isotope ratio is a much more sensitive and accurate marker for environmental contamination by spent uranium in comparison to the {sup 235}U/{sup 238}U isotope ratio. The ICP-MS technique allowed for the first time detection of irradiated uranium in soil samples even at distances more than 200 km to the north of Chernobyl NPP (Mogilev region). The concentration of {sup 236}U in the upper 0-10 cm soil layers varied from 2 x 10{sup -9} g g{sup -1} within radioactive spots close to the Chernobyl NPP to 3 x 10{sup -13} g g{sup -1} on a sampling site located by >200 km from Chernobyl.

  16. Mesoporous Silica Gel–Based Mixed Matrix Membranes for Improving Mass Transfer in Forward Osmosis: Effect of Pore Size of Filler

    Science.gov (United States)

    Lee, Jian-Yuan; Wang, Yining; Tang, Chuyang Y.; Huo, Fengwei

    2015-01-01

    The efficiency of forward osmosis (FO) process is generally limited by the internal concentration polarization (ICP) of solutes inside its porous substrate. In this study, mesoporous silica gel (SG) with nominal pore size ranging from 4–30 nm was used as fillers to prepare SG-based mixed matrix substrates. The resulting mixed matrix membranes had significantly reduced structural parameter and enhanced membrane water permeability as a result of the improved surface porosity of the substrates. An optimal filler pore size of ~9 nm was observed. This is in direct contrast to the case of thin film nanocomposite membranes, where microporous nanoparticle fillers are loaded to the membrane rejection layer and are designed in such a way that these fillers are able to retain solutes while allowing water to permeate through them. In the current study, the mesoporous fillers are designed as channels to both water and solute molecules. FO performance was enhanced at increasing filler pore size up to 9 nm due to the lower hydraulic resistance of the fillers. Nevertheless, further increasing filler pore size to 30 nm was accompanied with reduced FO efficiency, which can be attributed to the intrusion of polymer dope into the filler pores. PMID:26592565

  17. Mesoporous Silica Gel-Based Mixed Matrix Membranes for Improving Mass Transfer in Forward Osmosis: Effect of Pore Size of Filler.

    Science.gov (United States)

    Lee, Jian-Yuan; Wang, Yining; Tang, Chuyang Y; Huo, Fengwei

    2015-11-23

    The efficiency of forward osmosis (FO) process is generally limited by the internal concentration polarization (ICP) of solutes inside its porous substrate. In this study, mesoporous silica gel (SG) with nominal pore size ranging from 4-30 nm was used as fillers to prepare SG-based mixed matrix substrates. The resulting mixed matrix membranes had significantly reduced structural parameter and enhanced membrane water permeability as a result of the improved surface porosity of the substrates. An optimal filler pore size of ~9 nm was observed. This is in direct contrast to the case of thin film nanocomposite membranes, where microporous nanoparticle fillers are loaded to the membrane rejection layer and are designed in such a way that these fillers are able to retain solutes while allowing water to permeate through them. In the current study, the mesoporous fillers are designed as channels to both water and solute molecules. FO performance was enhanced at increasing filler pore size up to 9 nm due to the lower hydraulic resistance of the fillers. Nevertheless, further increasing filler pore size to 30 nm was accompanied with reduced FO efficiency, which can be attributed to the intrusion of polymer dope into the filler pores.

  18. ARSENIC DETERMINATION IN SALINE WATERS UTILIZING A TUBULAR MEMBRANE AS A GAS-LIQUID SEPATRATOR FOR HYDRIDE GENERATION INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY

    Science.gov (United States)

    A tubular silicone rubber membrane is evaluated as a gas-liquid separator for the determination of arsenic in saline waters via HG-ICP-MS. The system was optimized in terms of NaBH and HCI concentrations. The intermediate gas and carrier gas were optimized in terms of sensitiity ...

  19. An introduction to linear poroelasticity

    OpenAIRE

    Merxhani, Andi

    2016-01-01

    This study is an introduction to the theory of three-dimensional consolidation. The point of departure in the description are the basic equations of elasticity (i.e. constitutive law, equations of equilibrium in terms of stresses, and the definition of strain), together with the principle of effective stress, and the law of Darcy for fluid flow in porous media. These equations, together with the principle of mass conservation, are the only premises used to derive a drained description of cons...

  20. Novel amphiphilic polymeric ionic liquid-solid phase micro-extraction membrane for the preconcentration of aniline as degradation product of azo dye Orange G under sonication by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Cai, Mei-Qiang; Wei, Xiao-Qing; Du, Chun-Hui; Ma, Xu-Ming; Jin, Mi-Cong

    2014-07-04

    A novel amphiphilic polymeric ionic liquid membrane containing a hydrophilic bromide anion and a hydrophobic carbonyl group was synthesized in dimethylformamide (DMF) systems using the ionic liquid 1-butyl-3-vinylimidazolium bromide (BVImBr) and the methylmethacrylate (MMA) as monomers. The prepared amphiphilic ploy-methylmethacrylate-1-butyl-3-vinylimidazolium bromide (MMA-BVImBr) was characterized by a scanning electron microscope and an infrared spectrum instrument. The results of solid-phase micro-extraction membrane (SPMM) experiments showed that the adsorption capacity of membrane was about 0.76μgμg(-1) for aniline. Based on this, a sensitive method for the determination of trace aniline, as a degradation product of azo dye Orange G under sonication, was developed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The calibration curve showed a good linearity ranging from 0.5 to 10.0μgL(-1) with a correlation coefficient value of 0.9998. The limit of quantification was 0.5μgL(-1). The recoveries ranged from 90.6% to 96.1%. The intra- and inter-day relative standard deviations were less than 8.3% and 10.9%. The developed SPMM-LC-MS/MS method was used successfully for preconcentration of trace aniline produced during the sonication of Orange G solution. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Membrane Biophysics

    CERN Document Server

    Ashrafuzzaman, Mohammad

    2013-01-01

    Physics, mathematics and chemistry all play a vital role in understanding the true nature and functioning of biological membranes, key elements of living processes. Besides simple spectroscopic observations and electrical measurements of membranes we address in this book the phenomena of coexistence and independent existence of different membrane components using various theoretical approaches. This treatment will be helpful for readers who want to understand biological processes by applying both simple observations and fundamental scientific analysis. It provides a deep understanding of the causes and effects of processes inside membranes, and will thus eventually open new doors for high-level pharmaceutical approaches towards fighting membrane- and cell-related diseases.

  2. Investigation of separation factors of neptunium and plutonium in the process of mass transfer through liquid impregnated membranes with di-2-ethylhexylphosphoric acid

    International Nuclear Information System (INIS)

    Novikov, A.P.; Mikheeva, M.N.; Myasoedov, B.F.

    1990-01-01

    Kinetics of joint transfer of neptunium(6) and plutonium(4) through liquid membranes with di-2-ethylhexylphosphoric acid, depending on the concentration of the carrier, nature of reextracting agent and ratio of metal concentrations, was investigated. The optimal conditions for selective isolation of microimpurity of one of the elements from solutions of the other were determined. Solution of ammonium carbonate with carrier concentration of 0.1-0.2 mol/l can be expediently utilized as reextracting phase for neptunium impurity removal

  3. Pretreatment and Membrane Hydrophilic Modification to Reduce Membrane Fouling

    Directory of Open Access Journals (Sweden)

    Huaqiang Chu

    2013-09-01

    Full Text Available The application of low pressure membranes (microfiltration/ultrafiltration has undergone accelerated development for drinking water production. However, the major obstacle encountered in its popularization is membrane fouling caused by natural organic matter (NOM. This paper firstly summarizes the two factors causing the organic membrane fouling, including molecular weight (MW and hydrophilicity/hydrophobicity of NOM, and then presents a brief introduction of the methods which can prevent membrane fouling such as pretreatment of the feed water (e.g., coagulation, adsorption, and pre-oxidation and membrane hydrophilic modification (e.g., plasma modification, irradiation grafting modification, surface coating modification, blend modification, etc.. Perspectives of further research are also discussed.

  4. Microfabricated hydrogen sensitive membranes

    Energy Technology Data Exchange (ETDEWEB)

    Naddaf, A.; Kraetz, L. [Lehrstuhl fuer Thermische Verfahrenstechnik, Technische Universitaet Kaiserslautern (Germany); Detemple, P.; Schmitt, S.; Hessel, V. [Institut fuer Mikrotechnik Mainz GmbH, Mainz (Germany); Faqir, N. [University of Jordan, Amman (Jordan); Bart, H.J.

    2009-01-15

    Thin, defect-free palladium, palladium/copper and palladium/silver hydrogen absorbing membranes were microfabricated. A dual sputtering technique was used to deposit the palladium alloy membranes of only 1 {mu}m thickness on a nonporous silicon substrate. Advanced silicon etching (ASE) was applied on the backside to create a mechanically stable support structure for the thin films. Performance evaluation was carried out for different gases in a temperature range of 20 C to 298 C at a constant differential pressure of 110 kPa at the two sides of the membrane. The composite membranes show an excellent permeation rate of hydrogen, which appears to be 0.05 Pa m{sup 3} s{sup -1} and 0.01.10{sup -3} Pa m{sup 3} s{sup -1} at 20 C for the microfabricated 23 % silver and the 53 % copper composite membranes, respectively. The selectivity to hydrogen over a gas mixture containing, in addition to hydrogen, carbon monoxide, carbon dioxide and nitrogen was measured. The mass spectrometer did not detect any CO{sub 2} or CO, showing that the membrane is completely hydrogen selective. The microfabricated membranes exhibit both high mechanical strength (they easily withstand pressures up to 4 bar) and high thermal stability (up to 650 C). (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  5. Introduction to IBS

    Science.gov (United States)

    ... Day Art of IBS Gallery Contact Us Search Introduction to IBS Details What is IBS? Last Updated: ... tax-deductible donation. Make Donation What is IBS? Introduction to IBS Symptoms of IBS What Causes IBS? ...

  6. A conformational investigation of propeptide binding to the integral membrane protein γ-glutamyl carboxylase using nanodisc hydrogen exchange mass spectrometry

    DEFF Research Database (Denmark)

    Parker, Christine H; Morgan, Christopher R; Rand, Kasper Dyrberg

    2014-01-01

    of carboxylation co-substrates. Noteworthy modifications in HX of GGCX were prominently observed in GGCX peptides 491-507 and 395-401 upon pCon association, consistent with regions previously identified as sites for propeptide and glutamate binding. Several additional protein regions exhibited minor gains...... in solvent protection upon propeptide incorporation, providing evidence for a structural reorientation of the GGCX complex in association with VKD carboxylation. The results herein demonstrate that nanodisc-HX MS can be utilized to study molecular interactions of membrane-bound enzymes in the absence...

  7. Real Time Extraction Kinetics of Electro Membrane Extraction Verified by Comparing Drug Metabolism Profiles Obtained from a Flow-Flow Electro Membrane Extraction-Mass Spectrometry System with LC-MS

    DEFF Research Database (Denmark)

    Fuchs, David; Jensen, Henrik; Pedersen-Bjergaard, Stig

    2015-01-01

    A simple to construct and operate, "dip-in" electromembrane extraction (EME) probe directly coupled to electrospray ionization-mass spectrometry (ESI-MS) for rapid extraction and real time analysis of various analytes was developed. The setup demonstrated that EME-MS can be used as a viable...... alternative to conventional protein precipitation followed by liquid chromatography-mass spectrometry (LC-MS) for studying drug metabolism. Comparison of EME-MS with LC-MS for drug metabolism analysis demonstrated for the first time that real time extraction of analytes by EME is possible. Metabolism kinetics...... offering a significant time saving as compared to conventional LC-MS where laborious protein precipitation or other sample pretreatments are required before analysis. This makes the developed EME-MS setup a highly promising sample preparation method for various kinds of applications where fast and real-time...

  8. Astrophysics a very short introduction

    CERN Document Server

    Binney, James

    2016-01-01

    Astrophysics is the physics of the stars, and more widely the physics of the Universe. It enables us to understand the structure and evolution of planetary systems, stars, galaxies, interstellar gas, and the cosmos as a whole. In this Very Short Introduction, the leading astrophysicist James Binney shows how the field of astrophysics has expanded rapidly in the past century, with vast quantities of data gathered by telescopes exploiting all parts of the electromagnetic spectrum, combined with the rapid advance of computing power, which has allowed increasingly effective mathematical modelling. He illustrates how the application of fundamental principles of physics - the consideration of energy and mass, and momentum - and the two pillars of relativity and quantum mechanics, has provided insights into phenomena ranging from rapidly spinning millisecond pulsars to the collision of giant spiral galaxies. This is a clear, rigorous introduction to astrophysics for those keen to cut their teeth on a conceptual trea...

  9. Flux Enhancement in Membrane Distillation Using Nanofiber Membranes

    Directory of Open Access Journals (Sweden)

    T. Jiříček

    2016-01-01

    Full Text Available Membrane distillation (MD is an emerging separation technology, whose largest application potential lies in the desalination of highly concentrated solutions, which are out of the scope of reverse osmosis. Despite many attractive features, this technology is still awaiting large industrial application. The main reason is the lack of commercially available membranes with fluxes comparable to reverse osmosis. MD is a thermal separation process driven by a partial vapour pressure difference. Flux, distillate purity, and thermal efficiency are always in conflict, all three being strictly connected with pore size, membrane hydrophobicity, and thickness. The world has not seen the ideal membrane yet, but nanofibers may offer a solution to these contradictory requirements. Membranes of electrospun PVDF were tested under various conditions on a direct contact (DCMD unit, in order to determine the optimum conditions for maximum flux. In addition, their performance was compared to commonly available PTFE, PE, and PES membranes. It was confirmed that thinner membranes have higher fluxes and a lower distillate purity and also higher energy losses via conduction across the membrane. As both mass and heat transfer are connected, it is best to develop new membranes with a target application in mind, for the specific membrane module and operational conditions.

  10. Introduction to graph theory

    CERN Document Server

    Trudeau, Richard J

    1994-01-01

    Preface1. Pure Mathematics Introduction; Euclidean Geometry as Pure Mathematics; Games; Why Study Pure Mathematics?; What's Coming; Suggested Reading2. Graphs Introduction; Sets; Paradox; Graphs; Graph diagrams; Cautions; Common Graphs; Discovery; Complements and Subgraphs; Isomorphism; Recognizing Isomorphic Graphs; Semantics The Number of Graphs Having a Given nu; Exercises; Suggested Reading3. Planar Graphs Introduction; UG, K subscript 5, and the Jordan Curve Theorem; Are there More Nonplanar Graphs?; Expansions; Kuratowski's Theorem; Determining Whether a Graph is Planar or

  11. Bayesian Networks An Introduction

    CERN Document Server

    Koski, Timo

    2009-01-01

    Bayesian Networks: An Introduction provides a self-contained introduction to the theory and applications of Bayesian networks, a topic of interest and importance for statisticians, computer scientists and those involved in modelling complex data sets. The material has been extensively tested in classroom teaching and assumes a basic knowledge of probability, statistics and mathematics. All notions are carefully explained and feature exercises throughout. Features include:.: An introduction to Dirichlet Distribution, Exponential Families and their applications.; A detailed description of learni

  12. Introduction to imprecise probabilities

    CERN Document Server

    Augustin, Thomas; de Cooman, Gert; Troffaes, Matthias C M

    2014-01-01

    In recent years, the theory has become widely accepted and has been further developed, but a detailed introduction is needed in order to make the material available and accessible to a wide audience. This will be the first book providing such an introduction, covering core theory and recent developments which can be applied to many application areas. All authors of individual chapters are leading researchers on the specific topics, assuring high quality and up-to-date contents. An Introduction to Imprecise Probabilities provides a comprehensive introduction to imprecise probabilities, includin

  13. Introduction to clinical nutrition

    National Research Council Canada - National Science Library

    Sardesai, Vishwanath M

    2012-01-01

    .... Introduction to Clinical Nutrition, Third edition discusses the physiologic and metabolic interrelationships of all nutrients and their roles in health maintenance and the prevention of various...

  14. Membrane paradigm

    International Nuclear Information System (INIS)

    Price, R.H.; Thorne, K.S.

    1986-01-01

    The membrane paradigm is a modified frozen star approach to modeling black holes, with particles and fields assuming a complex, static, boundary-layer type structure (membrane) near the event horizon. The membrane has no effects on the present or future evolution of particles and fields above itself. The mathematical representation is a combination of a formalism containing terms for the shear and bulk viscosity, surface pressure, momentum, temperature, entropy, etc., of the horizon and the 3+1 formalism. The latter model considers a family of three-dimensional spacelike hypersurfaces in one-dimensional time. The membrane model considers a magnetic field threading the hole and undergoing torque from the hole rotation. The field is cleaned by the horizon and distributed over the horizon so that ohmic dissipation is minimized. The membrane paradigm is invalid inside the horizon, but is useful for theoretically probing the properties of slowly evolving black holes

  15. Membrane processes

    Science.gov (United States)

    Staszak, Katarzyna

    2017-11-01

    The membrane processes have played important role in the industrial separation process. These technologies can be found in all industrial areas such as food, beverages, metallurgy, pulp and paper, textile, pharmaceutical, automotive, biotechnology and chemical industry, as well as in water treatment for domestic and industrial application. Although these processes are known since twentieth century, there are still many studies that focus on the testing of new membranes' materials and determining of conditions for optimal selectivity, i. e. the optimum transmembrane pressure (TMP) or permeate flux to minimize fouling. Moreover the researchers proposed some calculation methods to predict the membrane processes properties. In this article, the laboratory scale experiments of membrane separation techniques, as well their validation by calculation methods are presented. Because membrane is the "heart" of the process, experimental and computational methods for its characterization are also described.

  16. Introduction to surveillance studies

    CERN Document Server

    Petersen, JK

    2012-01-01

    Introduction & OverviewIntroduction Brief History of Surveillance Technologies & TechniquesOptical SurveillanceAerial Surveillance Audio Surveillance Radio-Wave SurveillanceGlobal Positioning Systems Sensors Computers & the Internet Data Cards Biochemical Surveillance Animal Surveillance Biometrics Genetics Practical ConsiderationsPrevalence of Surveillance Effectiveness of Surveillance Freedom & Privacy IssuesConstitutional Freedoms Privacy Safeguards & Intrusions ResourcesReferences Glossary Index

  17. Introduction to Part 3

    DEFF Research Database (Denmark)

    Petersen, Nils Holger

    2015-01-01

    A brief contextualising discussion of Western Music History and its relations to Theological Aesthetical Thought since Carolingian Times as an introduction to 3 music articles in Part 3 of the volume.......A brief contextualising discussion of Western Music History and its relations to Theological Aesthetical Thought since Carolingian Times as an introduction to 3 music articles in Part 3 of the volume....

  18. Environmental Psychology: An Introduction

    NARCIS (Netherlands)

    Steg, L.; Berg, van den A.E.; Groot, de J.I.M.

    2012-01-01

    Environmental Psychology: An Introduction offers a research-based introduction to the psychological relationship between humans and their built and natural environments and discusses how sustainable environments can be created to the benefit of both people and nature •Explores the environment's

  19. Primordial membranes

    DEFF Research Database (Denmark)

    Hanczyc, Martin M; Monnard, Pierre-Alain

    2017-01-01

    Cellular membranes, which are self-assembled bilayer structures mainly composed of lipids, proteins and conjugated polysaccharides, are the defining feature of cell physiology. It is likely that the complexity of contemporary cells was preceded by simpler chemical systems or protocells during...... the various evolutionary stages that led from inanimate to living matter. It is also likely that primitive membranes played a similar role in protocell 'physiology'. The composition of such ancestral membranes has been proposed as mixtures of single hydrocarbon chain amphiphiles, which are simpler versions...

  20. Membranous nephropathy

    Science.gov (United States)

    ... skin-lightening creams Systemic lupus erythematosus , rheumatoid arthritis, Graves disease, and other autoimmune disorders The disorder occurs at ... diagnosis. The following tests can help determine the cause of membranous nephropathy: Antinuclear antibodies test Anti-double- ...

  1. Introduction to quantum mechanics

    CERN Document Server

    Phillips, A C

    2003-01-01

    Introduction to Quantum Mechanics is an introduction to the power and elegance of quantum mechanics. Assuming little in the way of prior knowledge, quantum concepts are carefully and precisely presented, and explored through numerous applications and problems. Some of the more challenging aspects that are essential for a modern appreciation of the subject have been included, but are introduced and developed in the simplest way possible.Undergraduates taking a first course on quantum mechanics will find this text an invaluable introduction to the field and help prepare them for more adv

  2. Evaluation of clayey masses compositions starting from the residue incorporation of the red ceramic industry to obtain tubular ceramic membranes; Avaliacao das composicoes de massas argilosas a partir da incorporacao de residuo da industria de ceramica vermelha na obtencao de membranas ceramicas tubulares

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Adriano Lima da; Chaves, Alexsandra Cristina; Luna, Carlos Bruno Barreto; Neves, Gelmires de Araujo; Lira, Helio de Lucena, E-mail: adrianolimadasilva@hotmail.com, E-mail: alexsandra.chaves@ifap.edu.br, E-mail: brunobarretodemaufcg@hotmail.com, E-mail: gelmires@ufcg.edu.br, E-mail: helio@ufcg.edu.br [Universidade Federal de Campina Grande (UAEMa/CCT/UFCG), PB (Brazil). Unidade Academica de Engenharia de Materiais

    2017-01-15

    The inappropriate residue disposal of red ceramic industry is very high. Nowadays, one of the major challenges is the investigation of processes to obtain alternative materials, enabling the use of these residues to manufacture new materials. This work's objective is to study clayey masses' compositions starting from the residue incorporation of the red ceramic industry to be used in tubular ceramic membranes. Two compositions of ceramic masses were established, composition A (50% of residue) and composition B (70% of residue). Granulometric analysis of the ceramic masses presented an average size of particles, what indicates membranes in the microfiltration scale. Another observed factor is related to the increase of residue amount, what favored a decrease in the ceramic mass' plasticity. A rise in the apparent porosity was also observed, probably because of a possible growing in the bigger pores numbers, due to the sintering high temperature and the elevation of residue quantity itself. (author)

  3. Western blotting: an introduction.

    Science.gov (United States)

    Kurien, Biji T; Scofield, R Hal

    2015-01-01

    Western blotting is an important procedure for the immunodetection of proteins, particularly proteins that are of low abundance. This process involves the transfer of protein patterns from gel to microporous membrane. Electrophoretic as well as non-electrophoretic transfer of proteins to membranes was first described in 1979. Protein blotting has evolved greatly since the inception of this protocol, allowing protein transfer to be accomplished in a variety of ways.

  4. Introduction to Pulmonary Fibrosis

    Science.gov (United States)

    ... page: Introduction to Pulmonary Fibrosis What Is Pulmonary Fibrosis? Pulmonary fibrosis is a disease where there is scarring ... of pulmonary fibrosis. Learn more How Is Pulmonary Fibrosis Diagnosed? Pulmonary fibrosis can be difficult to diagnose, so it ...

  5. MOOC Introduction to Dutch

    NARCIS (Netherlands)

    den Hollander, Franciscus; Piersma, Kristien

    Interview met Margriet Hidding, Birgit Lijmbach en Jeroen van Engen, medewerkers van het Talencentrum en de makers van de Massive Open Online Course (MOOC) Introduction to Dutch over het grote succes van deze cursus

  6. Radiation Protection: introduction

    International Nuclear Information System (INIS)

    Loos, M.

    2005-01-01

    The abstract gives an overview and introduction to the activities of SCK-CEN's Radiation Protection department. Main strategic developments and achievements in the field of life sciences, policy supports and medical applications are summarised

  7. Introduction: Ideologies of Youth

    African Journals Online (AJOL)

    seriane.camara

    2011-12-01

    Dec 1, 2011 ... target all age groups in their youth-oriented programmes. If the donor- ... van Dijk, de Bruijn, Cardoso, Butter: Introduction – Ideologies of Youth ...... Toward a Theory of Vital Conjunctures', American Anthropologist, vol. 104,.

  8. Complex Systems: An Introduction

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 9. Complex Systems: An Introduction - Anthropic Principle, Terrestrial Complexity, Complex Materials. V K Wadhawan. General Article Volume 14 Issue 9 September 2009 pp 894-906 ...

  9. Introduction: perspectives on Porter

    NARCIS (Netherlands)

    F.A.J. van den Bosch (Frans)

    1997-01-01

    textabstractIntroduction. Relevance of Strategy research: focus on Michael Porter's contributions Strategy is a fascinating field of enquiry, both for managers looking for a sustainable competitive advantage and for academic researchers looking for the reasons behind superior firm performance.

  10. Introduction to graph theory

    CERN Document Server

    Wilson, Robin J

    1985-01-01

    Graph Theory has recently emerged as a subject in its own right, as well as being an important mathematical tool in such diverse subjects as operational research, chemistry, sociology and genetics. This book provides a comprehensive introduction to the subject.

  11. Introduction to numerical analysis

    CERN Document Server

    Hildebrand, F B

    1987-01-01

    Well-known, respected introduction, updated to integrate concepts and procedures associated with computers. Computation, approximation, interpolation, numerical differentiation and integration, smoothing of data, other topics in lucid presentation. Includes 150 additional problems in this edition. Bibliography.

  12. Identification of V-type nerve agents in vapor samples using a field-portable capillary gas chromatography/membrane-interfaced electron ionization quadrupole mass spectrometry instrument with Tri-Bed concentrator and fluoridating conversion tube.

    Science.gov (United States)

    Ohrui, Y; Nagoya, T; Kurimata, N; Sodeyama, M; Seto, Y

    2017-07-01

    A field-portable gas chromatography-mass spectrometry (GC-MS) system (Hapsite ER) was evaluated for the detection of nonvolatile V-type nerve agents (VX and Russian VX (RVX)) in the vapor phase. The Hapsite ER system consists of a Tri-Bed concentrator gas sampler, a nonpolar low thermal-mass capillary GC column and a hydrophobic membrane-interfaced electron ionization quadrupole mass spectrometer evacuated by a non-evaporative getter pump. The GC-MS system was attached to a VX-G fluoridating conversion tube containing silver nitrate and potassium fluoride. Sample vapors of VX and RVX were converted into O-ethyl methylphosphonofluoridate (EtGB) and O-isobutyl methylphosphonofluoridate (iBuGB), respectively. These fluoridated derivatives were detected within 10 min. No compounds were detected when the VX and RVX samples were analyzed without the conversion tube. A vapor sample of tabun (GA) was analyzed, in which GA and O-ethyl N,N-dimethylphosphoramidofluoridate were detected. The molar recovery percentages of EtGB and iBuGB from VX and RVX vapors varied from 0.3 to 17%, which was attributed to variations in the vaporization efficiency of the glass vapor container. The conversion efficiencies of the VX-G conversion tube for VX and RVX to their phosphonate derivatives were estimated to be 40%. VX and RVX vapors were detected at concentrations as low as 0.3 mg m -3 . Gasoline vapor was found to interfere with the analyses of VX and RVX. In the presence of 160 mg m -3 gasoline, the detection limits of VX and RVX vapor were increased to 20 mg m -3 . Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  13. Stochastic processes an introduction

    CERN Document Server

    Jones, Peter Watts

    2009-01-01

    Some Background on ProbabilityIntroduction Probability Conditional probability and independence Discrete random variables Continuous random variables Mean and variance Some standard discrete probability distributions Some standard continuous probability distributions Generating functions Conditional expectationSome Gambling ProblemsGambler's ruin Probability of ruin Some numerical simulations Duration of the game Some variations of gambler's ruinRandom WalksIntroduction Unrestricted random walks The probability distribution after n steps First returns of the symmetric random walkMarkov ChainsS

  14. Introduction to elementary particles

    CERN Document Server

    Griffiths, David J

    2008-01-01

    This is the first quantitative treatment of elementary particle theory that is accessible to undergraduates. Using a lively, informal writing style, the author strikes a balance between quantitative rigor and intuitive understanding. The first chapter provides a detailed historical introduction to the subject. Subsequent chapters offer a consistent and modern presentation, covering the quark model, Feynman diagrams, quantum electrodynamics, and gauge theories. A clear introduction to the Feynman rules, using a simple model, helps readers learn the calculational techniques without the complicat

  15. Introduction to Geostatistics

    Science.gov (United States)

    Kitanidis, P. K.

    1997-05-01

    Introduction to Geostatistics presents practical techniques for engineers and earth scientists who routinely encounter interpolation and estimation problems when analyzing data from field observations. Requiring no background in statistics, and with a unique approach that synthesizes classic and geostatistical methods, this book offers linear estimation methods for practitioners and advanced students. Well illustrated with exercises and worked examples, Introduction to Geostatistics is designed for graduate-level courses in earth sciences and environmental engineering.

  16. Introduction to remote sensing

    CERN Document Server

    Cracknell, Arthur P

    2007-01-01

    Addressing the need for updated information in remote sensing, Introduction to Remote Sensing, Second Edition provides a full and authoritative introduction for scientists who need to know the scope, potential, and limitations in the field. The authors discuss the physical principles of common remote sensing systems and examine the processing, interpretation, and applications of data. This new edition features updated and expanded material, including greater coverage of applications from across earth, environmental, atmospheric, and oceanographic sciences. Illustrated with remotely sensed colo

  17. Plasma physics an introduction

    CERN Document Server

    Fitzpatrick, Richard

    2014-01-01

    Plasma Physics: An Introduction is based on a series of university course lectures by a leading name in the field, and thoroughly covers the physics of the fourth state of matter. This book looks at non-relativistic, fully ionized, nondegenerate, quasi-neutral, and weakly coupled plasma. Intended for the student market, the text provides a concise and cohesive introduction to plasma physics theory, and offers a solid foundation for students wishing to take higher level courses in plasma physics.

  18. Axionic membranes

    International Nuclear Information System (INIS)

    Aurilia, A.; Spallucci, E.

    1992-01-01

    A metal ring removed from a soap-water solution encloses a film of soap which can be mathematically described as a minimal surface having the ring as its only boundary. This is known to everybody. In this letter we suggest a relativistic extension of the above fluidodynamic system where the soap film is replaced by a Kalb-Ramand gauge potential B μν (x) and the ring by a closed string. The interaction between the B μν field and the string current excites a new configuration of the system consisting of a relativistic membrane bounded by the string. We call such a classical solution of the equation of motion an axionic membrane. As a dynamical system, the axionic membrane admits a Hamilton-Jacobi formulation which is an extension of the HJ theory of electromagnetic strings. (orig.)

  19. Identification of chemical warfare agents from vapor samples using a field-portable capillary gas chromatography/membrane-interfaced electron ionization quadrupole mass spectrometry instrument with Tri-Bed concentrator.

    Science.gov (United States)

    Nagashima, Hisayuki; Kondo, Tomohide; Nagoya, Tomoki; Ikeda, Toru; Kurimata, Naoko; Unoke, Shohei; Seto, Yasuo

    2015-08-07

    A field-portable gas chromatograph-mass spectrometer (Hapsite ER system) was evaluated for the detection of chemical warfare agents (CWAs) in the vapor phase. The system consisted of Tri-Bed concentrator gas sampler (trapping time: 3s(-1)min), a nonpolar low thermal-mass capillary gas chromatography column capable of raising temperatures up to 200°C, a hydrophobic membrane-interfaced electron ionization quadrupole mass spectrometer evacuated by a non-evaporative getter pump for data acquisition, and a personal computer for data analysis. Sample vapors containing as little as 22μg sarin (GB), 100μg soman (GD), 210μg tabun (GA), 55μg cyclohexylsarin (GF), 4.8μg sulfur mustard, 390μg nitrogen mustard 1, 140μg of nitrogen mustard 2, 130μg nitrogen mustard 3, 120μg of 2-chloroacetophenone and 990μg of chloropicrin per cubic meter could be confirmed after Tri-Bed micro-concentration (for 1min) and automated AMDIS search within 12min. Using manual deconvolution by background subtraction of neighboring regions on the extracted ion chromatograms, the above-mentioned CWAs could be confirmed at lower concentration levels. The memory effects were also examined and we found that blister agents showed significantly more carry-over than nerve agents. Gasoline vapor was found to interfere with the detection of GB and GD, raising the concentration limits for confirmation in the presence of gasoline by both AMDIS search and manual deconvolution; however, GA and GF were not subject to interference by gasoline. Lewisite 1, and o-chlorobenzylidene malononitrile could also be confirmed by gas chromatography, but it was hard to quantify them. Vapors of phosgene, chlorine, and cyanogen chloride could be confirmed by direct mass spectrometric detection at concentration levels higher than 2, 140, and 10mg/m(3) respectively, by bypassing the micro-concentration trap and gas chromatographic separation. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Chelating polymeric membranes

    KAUST Repository

    Peinemann, Klaus-Viktor; Villalobos Vazquez de la Parra, Luis Francisco; Hilke, Roland

    2015-01-01

    microporous chelating polymeric membrane. Embodiments include, but are not limited to, microporous chelating polymeric membranes, device comprising the membranes, and methods of using and making the same.

  1. Biophysics an introduction

    CERN Document Server

    Cotteril, Rodney

    2002-01-01

    Biophysics: An Introduction, is a concise balanced introduction to this subject. Written in an accessible and readable style, the book takes a fresh, modern approach with the author successfully combining key concepts and theory with relevant applications and examples drawn from the field as a whole. Beginning with a brief introduction to the origins of biophysics, the book takes the reader through successive levels of complexity, from atoms to molecules, structures, systems and ultimately to the behaviour of organisms. The book also includes extensive coverage of biopolymers, biomembranes, biological energy, and nervous systems. The text not only explores basic ideas, but also discusses recent developments, such as protein folding, DNA/RNA conformations, molecular motors, optical tweezers and the biological origins of consciousness and intelligence.

  2. Introduction to magnetochemistry

    CERN Document Server

    Earnshaw, Alan

    2013-01-01

    Introduction to Magnetochemistry provides an introduction to the more important aspects of magnetochemistry. The measurement of magnetic moment has been one of the most consistently useful to coordination chemists. For teaching purposes it provides a simple method of illustrating the ideas of electronic structure, and in research it can provide fundamental information about the bonding and stereochemistry of complexes. The book contains six chapters covering topics such as free atoms and ions, transition metal complexes, crystal field theory, second and third row transition metal complexes, a

  3. An Introduction to Malware

    DEFF Research Database (Denmark)

    Sharp, Robin

    2007-01-01

    These notes intended for use in DTU course 02233 on Network Security give a short introduction to the topic of malware. The most important types of malware are described, together with their basic principles of operation and dissemination, and defences against malware are discussed.......These notes intended for use in DTU course 02233 on Network Security give a short introduction to the topic of malware. The most important types of malware are described, together with their basic principles of operation and dissemination, and defences against malware are discussed....

  4. An Introduction to Malware

    DEFF Research Database (Denmark)

    Sharp, Robin

    2017-01-01

    These notes, intended for use in DTU course 02233 on Network Security, give a short introduction to the topic of malware. The most important types of malware are described, together with their basic principles of operation and dissemination, and defenses against malware are discussed.......These notes, intended for use in DTU course 02233 on Network Security, give a short introduction to the topic of malware. The most important types of malware are described, together with their basic principles of operation and dissemination, and defenses against malware are discussed....

  5. Introduction to adaptive arrays

    CERN Document Server

    Monzingo, Bob; Haupt, Randy

    2011-01-01

    This second edition is an extensive modernization of the bestselling introduction to the subject of adaptive array sensor systems. With the number of applications of adaptive array sensor systems growing each year, this look at the principles and fundamental techniques that are critical to these systems is more important than ever before. Introduction to Adaptive Arrays, 2nd Edition is organized as a tutorial, taking the reader by the hand and leading them through the maze of jargon that often surrounds this highly technical subject. It is easy to read and easy to follow as fundamental concept

  6. Introduction to quantum groups

    CERN Document Server

    Chaichian, Masud

    1996-01-01

    In the past decade there has been an extemely rapid growth in the interest and development of quantum group theory.This book provides students and researchers with a practical introduction to the principal ideas of quantum groups theory and its applications to quantum mechanical and modern field theory problems. It begins with a review of, and introduction to, the mathematical aspects of quantum deformation of classical groups, Lie algebras and related objects (algebras of functions on spaces, differential and integral calculi). In the subsequent chapters the richness of mathematical structure

  7. Applied energy an introduction

    CERN Document Server

    Abdullah, Mohammad Omar

    2012-01-01

    Introduction to Applied EnergyGeneral IntroductionEnergy and Power BasicsEnergy EquationEnergy Generation SystemsEnergy Storage and MethodsEnergy Efficiencies and LossesEnergy industry and Energy Applications in Small -Medium Enterprises (SME) industriesEnergy IndustryEnergy-Intensive industryEnergy Applications in SME Energy industriesEnergy Sources and SupplyEnergy SourcesEnergy Supply and Energy DemandEnergy Flow Visualization and Sankey DiagramEnergy Management and AnalysisEnergy AuditsEnergy Use and Fuel Consumption StudyEnergy Life-Cycle AnalysisEnergy and EnvironmentEnergy Pollutants, S

  8. Introduction to nonimaging optics

    CERN Document Server

    Chaves, Julio

    2015-01-01

    Introduction to Nonimaging Optics covers the theoretical foundations and design methods of nonimaging optics, as well as key concepts from related fields. This fully updated, revised, and expanded Second Edition: Features a new and intuitive introduction with a basic description of the advantages of nonimaging opticsAdds new chapters on wavefronts for a prescribed output (irradiance or intensity), infinitesimal étendue optics (generalization of the aplanatic optics), and Köhler optics and color mixingIncorporates new material on the simultaneous multiple surface (SMS) design method in 3-D, int

  9. Introduction to fuzzy systems

    CERN Document Server

    Chen, Guanrong

    2005-01-01

    Introduction to Fuzzy Systems provides students with a self-contained introduction that requires no preliminary knowledge of fuzzy mathematics and fuzzy control systems theory. Simplified and readily accessible, it encourages both classroom and self-directed learners to build a solid foundation in fuzzy systems. After introducing the subject, the authors move directly into presenting real-world applications of fuzzy logic, revealing its practical flavor. This practicality is then followed by basic fuzzy systems theory. The book also offers a tutorial on fuzzy control theory, based mainly on th

  10. Introduction to information processing

    CERN Document Server

    Dietel, Harvey M

    2014-01-01

    An Introduction to Information Processing provides an informal introduction to the computer field. This book introduces computer hardware, which is the actual computing equipment.Organized into three parts encompassing 12 chapters, this book begins with an overview of the evolution of personal computing and includes detailed case studies on two of the most essential personal computers for the 1980s, namely, the IBM Personal Computer and Apple's Macintosh. This text then traces the evolution of modern computing systems from the earliest mechanical calculating devices to microchips. Other chapte

  11. Game theory an introduction

    CERN Document Server

    Barron, E N

    2013-01-01

    An exciting new edition of the popular introduction to game theory and its applications The thoroughly expanded Second Edition presents a unique, hands-on approach to game theory. While most books on the subject are too abstract or too basic for mathematicians, Game Theory: An Introduction, Second Edition offers a blend of theory and applications, allowing readers to use theory and software to create and analyze real-world decision-making models. With a rigorous, yet accessible, treatment of mathematics, the book focuses on results that can be used to

  12. Acoustics an introduction

    CERN Document Server

    Kuttruff, Heinrich

    2006-01-01

    This definitive textbook provides students with a comprehensive introduction to acoustics. Beginning with the basic physical ideas, Acoustics balances the fundamentals with engineering aspects, applications and electroacoustics, also covering music, speech and the properties of human hearing. The concepts of acoustics are exposed and applied in:room acousticssound insulation in buildingsnoise controlunderwater sound and ultrasoundScientifically thorough, but with mathematics kept to a minimum, Acoustics is the perfect introduction to acoustics for students at any level of mechanical, electrical or civil engineering courses and an accessible resource for architects, musicians or sound engineers requiring a technical understanding of acoustics and their applications.

  13. Introduction to nuclear reactions

    International Nuclear Information System (INIS)

    Satchler, G.R.

    1980-01-01

    This introduction to nuclear reaction phenomena is aimed primarily but not exclusively at readers at the undergraduate student level. An overview of the subject is presented in the first two chapters entitled - Some background information and Introduction to nuclear reactions. The third chapter reviews scattering theory with emphasis on the underlying physical ideas and also provides schematic entrees to the more advanced topics. The physical models which have been developed to account for the various aspects of nuclear phenomena are described in more detail in chapter 4. References and exercises are appended to each chapter. (U.K.)

  14. Introduction to the Project

    DEFF Research Database (Denmark)

    Kuhn, Johan M.; Malchow-Møller, Nikolaj; Sørensen, Anders

    In this note a short introduction to the project “Employment Effects of Entrepreneurs” is presented. First, we describe the purpose of the project; second, we present the background; third, we briefly describe the three papers that constitute the output of the project, and fourth, we discuss two ...... important qualifications for the understanding of the contributions and results established in the project.......In this note a short introduction to the project “Employment Effects of Entrepreneurs” is presented. First, we describe the purpose of the project; second, we present the background; third, we briefly describe the three papers that constitute the output of the project, and fourth, we discuss two...

  15. Introduction to UAV systems

    CERN Document Server

    Fahlstrom, Paul

    2012-01-01

    Unmanned aerial vehicles (UAVs) have been widely adopted in the military world over the last decade and the success of these military applications is increasingly driving efforts to establish unmanned aircraft in non-military roles. Introduction to UAV Systems, 4th edition provides a comprehensive introduction to all of the elements of a complete Unmanned Aircraft System (UAS). It addresses the air vehicle, mission planning and control, several types of mission payloads, data links and how they interact with mission performance, and launch and recovery concepts. This

  16. Fall Protection Introduction, #33462

    Energy Technology Data Exchange (ETDEWEB)

    Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-23

    The proper use of fall prevention and fall protection controls can reduce the risk of deaths and injuries caused by falls. This course, Fall Protection Introduction (#33462), is designed as an introduction to various types of recognized fall prevention and fall protection systems at Los Alamos National Laboratory (LANL), including guardrail systems, safety net systems, fall restraint systems, and fall arrest systems. Special emphasis is given to the components, inspection, care, and storage of personal fall arrest systems (PFASs). This course also presents controls for falling object hazards and emergency planning considerations for persons who have fallen.

  17. Introduction to plasma dynamics

    CERN Document Server

    Morozov, A I

    2013-01-01

    As the twenty-first century progresses, plasma technology will play an increasing role in our lives, providing new sources of energy, ion-plasma processing of materials, wave electromagnetic radiation sources, space plasma thrusters, and more. Studies of the plasma state of matter not only accelerate technological developments but also improve the understanding of natural phenomena. Beginning with an introduction to the characteristics and types of plasmas, Introduction to Plasma Dynamics covers the basic models of classical diffuse plasmas used to describe such phenomena as linear and shock w

  18. Screening therapeutics according to their uptake across the blood-brain barrier: A high throughput method based on immobilized artificial membrane liquid chromatography-diode-array-detection coupled to electrospray-time-of-flight mass spectrometry.

    Science.gov (United States)

    Russo, Giacomo; Grumetto, Lucia; Szucs, Roman; Barbato, Francesco; Lynen, Frederic

    2018-02-07

    The Blood-Brain Barrier (BBB) plays an essential role in protecting the brain tissues against possible injurious substances. In the present work, 79 neutral, basic, acidic and amphoteric structurally unrelated analytes were considered and their chromatographic retention coefficients on immobilized artificial membrane (IAM) stationary phase were determined employing a mass spectrometry (MS) -compatible buffer based on ammonium acetate. Their BBB passage predictive strength was evaluated and the statistical models based on IAM indexes and in silico physico-chemical descriptors showed solid statistics (r 2 (n-1) = 0.78). The predictive strength of the indexes achieved by the MS-compatible method was comparable to that achieved by employing the more "biomimetic" Dulbecco's phosphate buffered saline, even if some differences in the elution order were observed. The method was transferred to the MS, employing a diode-array-detection coupled to an electrospray ionization source and a time-of-flight analyzer. This setup allowed the simultaneous analysis of up to eight analytes, yielding a remarkable acceleration of the analysis time. Copyright © 2018. Published by Elsevier B.V.

  19. Development of an analytical method coupling cell membrane chromatography with gas chromatography-mass spectrometry via microextraction by packed sorbent and its application in the screening of volatile active compounds in natural products.

    Science.gov (United States)

    Li, Miao; Wang, Sicen; He, Langchong

    2015-01-01

    Natural products (NPs) are important sources of lead compounds in modern drug discovery. To facilitate the screening of volatile active compounds in NPs, we have developed a new biochromatography method that uses rat vascular smooth muscle cells (VSMC), which are rich in L-type calcium channels (LCC), to prepare the stationary phase. This integrated method, which couples cell membrane chromatography (CMC) with gas chromatography-mass spectrometry (GC-MS) via microextraction by packed sorbent (MEPS) technology, has been termed VSMC/CMC-MEPS-GC-MS. Methodological validation confirmed its specificity, reliability and convenience. Screening results for Radix Angelicae Dahuricae and Fructus Cnidii obtained using VSMC/CMC-MEPS-GC-MS were consistent with those obtained using VSMC/CMC-offline-GC-MS. MEPS connection plays as simplified solid-phase extraction and replaces the uncontrollable evaporation operation in reported offline connections, so our new method is supposed to be more efficient and reliable than the offline ones, especially for compounds that are volatile, thermally unstable or difficult to purify. In application, senkyunolide A and ligustilide were preliminary identified as the volatile active components in Rhizoma Chuanxiong. We have thus confirmed the suitability of VSMC/CMC-MEPS-GC-MS for volatile active compounds screening in NP. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Low fouling polysulfone ultrafiltration membrane via click chemistry

    KAUST Repository

    Xie, Yihui; Tayouo Djinsu, Russell; Nunes, Suzana Pereira

    2014-01-01

    %, and 94%). The glass transition temperature shifted with the introduction of triazole pendant groups from 190°C (unmodified) to 171°C. Ultrafiltration membranes were prepared via phase inversion by immersion in different coagulation baths (NMP

  1. Collider Physics an Experimental Introduction

    International Nuclear Information System (INIS)

    Elvezio Pagliarone, Carmine

    2011-01-01

    This paper reviews shortly a small part of the contents of a set of lectures, presented at the XIV International School of Particles and Fields in Morelia, state of Michoacan, Mexico, during November 2010. The main goal of those lectures was to introduce students to some of the basic ideas and tools required for experimental and phenomenological analysis of collider data. In particular, after an introduction to the scientific motivations, that drives the construction of powerful accelerator complexes, and the need of reaching high center of mass energies and luminosities, some basic concept about collider particle detectors will be discussed. A status about the present running colliders and collider experiments as well as future plans and research and development is also given.

  2. An introduction to extra dimensions

    International Nuclear Information System (INIS)

    Perez-Lorenzana, Abdel

    2005-01-01

    Models that involve extra dimensions have introduced completely new ways of looking up on old problems in theoretical physics. The aim of the present notes is to provide a brief introduction to the many uses that extra dimensions have found over the last few years, mainly following an effective field theory point of view. Most parts of the discussion are devoted to models with flat extra dimensions, covering both theoretical and phenomenological aspects. We also discuss some of the new ideas for model building where extra dimensions may play a role, including symmetry breaking by diverse new and old mechanisms. Some interesting applications of these ideas are discussed over the notes, including models for neutrino masses and proton stability. The last part of this review addresses some aspects of warped extra dimensions, and graviton localization

  3. Introduction to protein blotting.

    Science.gov (United States)

    Kurien, Biji T; Scofield, R Hal

    2009-01-01

    Protein blotting is a powerful and important procedure for the immunodetection of proteins following electrophoresis, particularly proteins that are of low abundance. Since the inception of the protocol for protein transfer from an electrophoresed gel to a membrane in 1979, protein blotting has evolved greatly. The scientific community is now confronted with a variety of ways and means to carry out this transfer.

  4. Introduction to quantum groups

    International Nuclear Information System (INIS)

    Monteiro, Marco A.R.

    1994-01-01

    An elementary introduction to quantum groups is presented. The example of Universal Enveloping Algebra of deformed SU(2) is analysed in detail. It is also discussed systems made up of bosonic q-oscillators at finite temperature within the formalism of Thermo-Field Dynamics. (author). 39 refs

  5. Introduction to nucleosynthesis

    International Nuclear Information System (INIS)

    Guasp, J.

    1975-01-01

    After a short introduction on stellar evolution, the physical foundations of nucleosynthesis are exposed: H, He, C and O fusion, Si burning and the equilibrium process. The effect of neutrinos in the last stages of stellar evolution and Supernova explosions are treated too. Afterwards the neutron capture process, fast and slow, are considerated concluding with cosmic nucleogenesis and nucleosynthesis in overmasive objects. (author)

  6. Russian: An Active Introduction.

    Science.gov (United States)

    De La Cruz, Nina

    The Active Introduction is one of the modules in an array of materials used in Russian training for beginners at the Foreign Service Institute. It is essentially a catalog of sentences relating to typical daily activities which can be combined to form different communication sequences in dialog form. Students learn to speak Russian through…

  7. Introduction to the Project

    DEFF Research Database (Denmark)

    Kuhn, Johan M.; Malchow-Møller, Nikolaj; Sørensen, Anders

    In this note a short introduction to the project “Employment Effects of Entrepreneurs” is presented. First, we describe the purpose of the project; second, we present the background; third, we briefly describe the three papers that constitute the output of the project, and fourth, we discuss two...... important qualifications for the understanding of the contributions and results established in the project....

  8. Introduction to LCA Methodology

    DEFF Research Database (Denmark)

    Hauschild, Michael Z.

    2018-01-01

    In order to offer the reader an overview of the LCA methodology in the preparation of the more detailed description of its different phases, a brief introduction is given to the methodological framework according to the ISO 14040 standard and the main elements of each of its phases. Emphasis...

  9. Introduction to Chiral Symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Volker [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-05-09

    These lectures are an attempt to a pedagogical introduction into the elementary concepts of chiral symmetry in nuclear physics. We will also discuss some effective chiral models such as the linear and nonlinear sigma model as well as the essential ideas of chiral perturbation theory. We will present some applications to the physics of ultrarelativistic heavy ion collisionsd.

  10. Introduction: Adapting Idols

    NARCIS (Netherlands)

    Joost Bruin; dr. Koos Zwaan

    2012-01-01

    Introduction book Adapting Idols Since the first series of Pop Idol aired in the UK just over a decade ago, Idols television shows have been broadcast in more than forty countries all over the world. In all those countries the global Idols format has been adapted to local cultures and production

  11. Introduction to topology

    CERN Document Server

    Mendelson, Bert

    1990-01-01

    Highly regarded for its exceptional clarity, imaginative and instructive exercises, and fine writing style, this concise book offers an ideal introduction to the fundamentals of topology. It provides a simple, thorough survey of elementary topics, starting with set theory and advancing to metric and topological spaces, connectedness, and compactness. 1975 edition.

  12. Introduction to statistics

    CERN Multimedia

    CERN. Geneva

    2005-01-01

    The three lectures will present an introduction to statistical methods as used in High Energy Physics. As the time will be very limited, the course will seek mainly to define the important issues and to introduce the most wide used tools. Topics will include the interpretation and use of probability, estimation of parameters and testing of hypotheses.

  13. Introduction to Statistics course

    CERN Multimedia

    CERN. Geneva HR-RFA

    2006-01-01

    The four lectures will present an introduction to statistical methods as used in High Energy Physics. As the time will be very limited, the course will seek mainly to define the important issues and to introduce the most wide used tools. Topics will include the interpretation and use of probability, estimation of parameters and testing of hypotheses.

  14. Introduction: The Transparency Issue

    NARCIS (Netherlands)

    Teurlings, J.; Stauff, M.

    2014-01-01

    Besides giving an overview on the individual contributions, this introduction to the special issue on transparency delineates a conceptual context for a critical analysis of the contemporary discourse on transparency and the media mechanisms related to it. It focuses on three ambivalences inherent

  15. Introduction to International Trade.

    Science.gov (United States)

    Crummett, Dan M.; Crummett, Jerrie

    This set of student and teacher guides is intended for use in a course to prepare students for entry-level employment in such occupational areas in international trade as business/finance, communications, logistics, and marketing. The following topics are covered in the course's five instructional units: introduction to careers in international…

  16. Introduction to association schemes

    NARCIS (Netherlands)

    Seidel, J.J.

    1991-01-01

    The present paper gives an introduction to the theory of association schemes, following Bose-Mesner (1959), Biggs (1974), Delsarte (1973), Bannai-Ito (1984) and Brouwer-Cohen-Neumaier (1989). Apart from definitions and many examples, also several proofs and some problems are included. The paragraphs

  17. An introduction to radiobiology

    International Nuclear Information System (INIS)

    Nias, A.H.W.; Dimbleby, R.

    1990-01-01

    This text provides an introduction to quantitative radiobiology with emphasis on practical aspects of the subject. Among the topics considered are reparable damage, densely ionizing radiation, normal and malignant cells, and whole body regulation. These and other aspects of radiation biology are described in detail

  18. Introduction to Shakespeare: English.

    Science.gov (United States)

    Hargraves, Richard

    The "Introduction to Shakespeare" course in the Quinmester Program involves the careful study of the tragedy "Romeo and Juliet" and the comedy "The Taming of the Shrew," emphasizing language, development of character and theme. The course also includes the study of biographical data relevant to the evolution of…

  19. Introduction to chiral symmetry

    International Nuclear Information System (INIS)

    Koch, V.

    1996-01-01

    These lectures are an attempt to a pedagogical introduction into the elementary concepts of chiral symmetry in nuclear physics. Effective chiral models such as the linear and nonlinear sigma model will be discussed as well as the essential ideas of chiral perturbation theory. Some applications to the physics of ultrarelativistic heavy ion collisions will be presented

  20. Introduction to HACCP.

    Science.gov (United States)

    Introduction to HACCP Deana R. Jones, Ph.D. Egg Safety and Quality Research Unit USDA-Agricultural Research Service Russell Research Center Athens, GA Deana.Jones@ars.usda.gov HACCP is an acronym for Hazard Analysis and Critical Control Point and was initially developed by the Pillsbury Company a...

  1. An Introduction to Malware

    OpenAIRE

    Sharp, Robin

    2017-01-01

    These notes, intended for use in DTU course 02233 on Network Security, give a short introduction to the topic of malware. The most important types of malware are described, together with their basic principles of operation and dissemination, and defenses against malware are discussed.

  2. Introduction to statistics

    CERN Multimedia

    CERN. Geneva

    2004-01-01

    The three lectures will present an introduction to statistical methods as used in High Energy Physics. As the time will be very limited, the course will seek mainly to define the important issues and to introduce the most wide used tools. Topics will include the interpretation and use of probability, estimation of parameters and testing of hypotheses.

  3. Introduction to ROC analysis

    International Nuclear Information System (INIS)

    Kelsey, C.A.; Mettler, F.A.

    1988-01-01

    An elementary introduction to ROC analysis illustrates how ROC curves depend on observer threshold levels and discusses the relation between ROC curve parameters and other measures of observer performance including accuracy sensitivity specificity true positive fraction, true negative fraction, false positive fraction and false negative fraction

  4. Introduction and fundamentals

    International Nuclear Information System (INIS)

    Thomas, R.H.

    1980-01-01

    This introduction discusses advances in the fundamental sciences which underlie the applied science of health physics and radiation protection. Risk assessments in nuclear medicine are made by defining the conditions of exposure, identification of adverse effects, relating exposure with effect, and estimation of the overall risk for ionizing radiations

  5. Labour and Passion. : Introduction

    NARCIS (Netherlands)

    Dr. Joke Hermes

    2014-01-01

    Abstract In this introduction to the themed section on ‘Labour and passion’, it is argued that work has bled into all areas of life. Political economists and media production researchers have shown how both paid and unpaid labour are singularly important and build upon one another. The set of

  6. Diophantine geometry an introduction

    CERN Document Server

    Hindry, Marc

    2000-01-01

    This is an introduction to diophantine geometry at the advanced graduate level. The book contains a proof of the Mordell conjecture which will make it quite attractive to graduate students and professional mathematicians. In each part of the book, the reader will find numerous exercises.

  7. Introduction to superstrings

    International Nuclear Information System (INIS)

    Kaku, M.

    1988-01-01

    This tutorial introduces the development of, and current trends in, superstring theory, a significant and still controversial attempt to unify general relatively and quantum field theory. Stressing current areas of research activity, Introduction to Superstrings addresses topics including string field theory, multi-loops and Teichmuller spaces, conformal field theory, and four-dimensional superstrings

  8. Introduction to number theory

    CERN Document Server

    Vazzana, Anthony; Garth, David

    2007-01-01

    One of the oldest branches of mathematics, number theory is a vast field devoted to studying the properties of whole numbers. Offering a flexible format for a one- or two-semester course, Introduction to Number Theory uses worked examples, numerous exercises, and two popular software packages to describe a diverse array of number theory topics.

  9. Biorefineries: A Short Introduction.

    Science.gov (United States)

    Wagemann, Kurt; Tippkötter, Nils

    2018-04-13

    The terms bioeconomy and biorefineries are used for a variety of processes and developments. This short introduction is intended to provide a delimitation and clarification of the terminology as well as a classification of current biorefinery concepts. The basic process diagrams of the most important biorefinery types are shown.

  10. Introduction to Film.

    Science.gov (United States)

    Burns, Gary

    There are numerous ways to structure the introduction to film course so as to meet the needs of the different types of students who typically enroll. Assuming there is no production component in the course, the teacher is left with two major approaches to choose from--historical and aesthetic. The units in the course will typically be built around…

  11. Introduction to Film Making.

    Science.gov (United States)

    Davis, Robert E.

    This booklet is intended for teachers who are now teaching units in film production as part of a program in communication or who wish to begin work with filmmaking in such a program. The first section is intended to serve as a brief introduction to film theory, while a major portion of the rest of the booklet is devoted to film projects which may…

  12. Introduction to particle physics

    International Nuclear Information System (INIS)

    Zitoun, R.

    2000-01-01

    This book proposes an introduction to particle physics that requires only a high-school level mathematical knowledge. Elementary particles (leptons, quarks, bosons) are presented according to a modern view taking into account of their symmetries and interactions. The author shows how physicists have elaborated the standard model and what are its implications in cosmology. (J.S.)

  13. Introduction to risk assessment

    International Nuclear Information System (INIS)

    Raina, V.M.

    2002-01-01

    This paper gives an introduction to risk assessment. It discusses the basic concepts of risk assessment, nuclear risk assessment process and products, the role of risk assessment products in nuclear safety assurance, the relationship between risk assessment and other safety analysis and risk assessment and safe operating envelope

  14. Successful introduction of innovations

    International Nuclear Information System (INIS)

    Schoots, K.; Jeeninga, H.

    2008-01-01

    The introduction of new technology is sometimes troubled by discontinuity in incentive schemes. By making prior assessments of the necessary means, the real time span for the incentive scheme and by maintaining this scheme until the technology is mature enough to enter the market, the success of innovation trajectories can be increased significantly. [mk] [nl

  15. Successful introduction of innovation

    International Nuclear Information System (INIS)

    Schoots, K.; Jeeninga, H.

    2008-01-01

    The introduction of new technology sometimes proceeds sluggishly due to discontinuity in incentive schemes. Estimating in advance which means are required, what a realistic time span is for the incentive scheme and continuing this scheme until the technology is marketable can significantly increase the success of innovation trajectories. [mk] [nl

  16. Chemical Safety – Introduction

    CERN Multimedia

    DG Unit

    2009-01-01

    A course of "Chemical Safety – Introduction" will be held in English on 29 May 2009, 9:30-12:00. There are some places left. If you are interested in participating, please register on the Training Catalogue. You will then receive an invitation by email.

  17. Advanced imaging as a novel approach to the characterization of membranes for microfiltration applications

    Science.gov (United States)

    Marroquin, Milagro

    The primary objectives of my dissertation were to design, develop and implement novel confocal microscopy imaging protocols for the characterization of membranes and highlight opportunities to obtain reliable and cutting-edge information of microfiltration membrane morphology and fouling processes. After a comprehensive introduction and review of confocal microscopy in membrane applications (Chapter 1), the first part of this dissertation (Chapter 2) details my work on membrane morphology characterization by confocal laser scanning microscopy (CLSM) and the implementation of my newly developed CLSM cross-sectional imaging protocol. Depth-of-penetration limits were identified to be approximately 24 microns and 7-8 microns for mixed cellulose ester and polyethersulfone membranes, respectively, making it impossible to image about 70% of the membrane bulk. The development and implementation of my cross-sectional CLSM method enabled the imaging of the entire membrane cross-section. Porosities of symmetric and asymmetric membranes with nominal pore sizes in the range 0.65-8.0 microns were quantified at different depths and yielded porosity values in the 50-60% range. It is my hope and expectation that the characterization strategy developed in this part of the work will enable future studies of different membrane materials and applications by confocal microscopy. After demonstrating how cross-sectional CLSM could be used to fully characterize membrane morphologies and porosities, I applied it to the characterization of fouling occurring in polyethersulfone microfiltration membranes during the processing of solutions containing proteins and polysaccharides (Chapter 3). Through CLSM imaging, it was determined where proteins and polysaccharides deposit throughout polymeric microfiltration membranes when a fluid containing these materials is filtered. CLSM enabled evaluation of the location and extent of fouling by individual components (protein: casein and polysaccharide

  18. MEMBRANE BIOTREATMENT OF VOC-LADEN AIR

    Science.gov (United States)

    The paper discusses membrane biotreatment of air laden with volatile organic compounds (VOCs). Microporous flat-sheet and hollow-fiber membrane contactors were used to support air-liquid mass transfer interfaces. These modules were used in a two-step process to transfer VOCs fr...

  19. Introduction to modern magnetohydrodynamics

    CERN Document Server

    Galtier, Sébastien

    2016-01-01

    Ninety-nine percent of ordinary matter in the Universe is in the form of ionized fluids, or plasmas. The study of the magnetic properties of such electrically conducting fluids, magnetohydrodynamics (MHD), has become a central theory in astrophysics, as well as in areas such as engineering and geophysics. This textbook offers a comprehensive introduction to MHD and its recent applications, in nature and in laboratory plasmas; from the machinery of the Sun and galaxies, to the cooling of nuclear reactors and the geodynamo. It exposes advanced undergraduate and graduate students to both classical and modern concepts, making them aware of current research and the ever-widening scope of MHD. Rigorous derivations within the text, supplemented by over 100 illustrations and followed by exercises and worked solutions at the end of each chapter, provide an engaging and practical introduction to the subject and an accessible route into this wide-ranging field.

  20. Introduction to linear elasticity

    CERN Document Server

    Gould, Phillip L

    2013-01-01

    Introduction to Linear Elasticity, 3rd Edition, provides an applications-oriented grounding in the tensor-based theory of elasticity for students in mechanical, civil, aeronautical, and biomedical engineering, as well as materials and earth science. The book is distinct from the traditional text aimed at graduate students in solid mechanics by introducing the subject at a level appropriate for advanced undergraduate and beginning graduate students. The author's presentation allows students to apply the basic notions of stress analysis and move on to advanced work in continuum mechanics, plasticity, plate and shell theory, composite materials, viscoelasticity and finite method analysis. This book also:  Emphasizes tensor-based approach while still distilling down to explicit notation Provides introduction to theory of plates, theory of shells, wave propagation, viscoelasticity and plasticity accessible to advanced undergraduate students Appropriate for courses following emerging trend of teaching solid mechan...

  1. Introduction to Abelian varieties

    CERN Document Server

    Murty, V Kumar

    1993-01-01

    The book represents an introduction to the theory of abelian varieties with a view to arithmetic. The aim is to introduce some of the basics of the theory as well as some recent arithmetic applications to graduate students and researchers in other fields. The first part contains proofs of the Abel-Jacobi theorem, Riemann's relations and the Lefschetz theorem on projective embeddings over the complex numbers in the spirit of S. Lang's book Introduction to algebraic and abelian functions. Then the Jacobians of Fermat curves as well as some modular curves are discussed. Finally, as an application, Faltings' proof of the Mordell conjecture and its intermediate steps, the Tate conjecture and the Shafarevich conjecture, are sketched. - H. Lange for MathSciNet.

  2. Introduction to Sporadic Groups

    Directory of Open Access Journals (Sweden)

    Luis J. Boya

    2011-01-01

    Full Text Available This is an introduction to finite simple groups, in particular sporadic groups, intended for physicists. After a short review of group theory, we enumerate the 1+1+16=18 families of finite simple groups, as an introduction to the sporadic groups. These are described next, in three levels of increasing complexity, plus the six isolated ''pariah'' groups. The (old five Mathieu groups make up the first, smallest order level. The seven groups related to the Leech lattice, including the three Conway groups, constitute the second level. The third and highest level contains the Monster group M, plus seven other related groups. Next a brief mention is made of the remaining six pariah groups, thus completing the 5+7+8+6=26 sporadic groups. The review ends up with a brief discussion of a few of physical applications of finite groups in physics, including a couple of recent examples which use sporadic groups.

  3. Introduction to computer networking

    CERN Document Server

    Robertazzi, Thomas G

    2017-01-01

    This book gives a broad look at both fundamental networking technology and new areas that support it and use it. It is a concise introduction to the most prominent, recent technological topics in computer networking. Topics include network technology such as wired and wireless networks, enabling technologies such as data centers, software defined networking, cloud and grid computing and applications such as networks on chips, space networking and network security. The accessible writing style and non-mathematical treatment makes this a useful book for the student, network and communications engineer, computer scientist and IT professional. • Features a concise, accessible treatment of computer networking, focusing on new technological topics; • Provides non-mathematical introduction to networks in their most common forms today;< • Includes new developments in switching, optical networks, WiFi, Bluetooth, LTE, 5G, and quantum cryptography.

  4. Mind a brief introduction

    CERN Document Server

    Searle, John R

    2004-01-01

    "The philosophy of mind is unique among contemporary philosophical subjects," writes John Searle, "in that all of the most famous and influential theories are false." One of the world's most eminent thinkers, Searle dismantles these theories as he presents a vividly written, comprehensive introduction to the mind. He begins with a look at the twelve problems of philosophy of mind--which he calls "Descartes and Other Disasters"--problems which he returns to throughout the volume, as he illuminates such topics as materialism, consciousness, the mind-body problem, intentionality, mental causation, free will, and the self. The book offers a refreshingly direct and engaging introduction to one of the most intriguing areas of philosophy.

  5. Guest Editor's Introduction

    DEFF Research Database (Denmark)

    Seeberg, Peter

    2015-01-01

    This introductory article’s point of departure is the transformation processes that have taken place in theMiddle East since 2011. It presents perspectives in the academic discussions following the surprising events in a post-‘Arab Spring’ scenario. The Introduction emphasizes that it is the ambi......This introductory article’s point of departure is the transformation processes that have taken place in theMiddle East since 2011. It presents perspectives in the academic discussions following the surprising events in a post-‘Arab Spring’ scenario. The Introduction emphasizes...... that it is the ambition of this collection of articles to discuss and make sense of the significant differences in the developments,where newgeopolitical dynamics reshape theMENA-region’s post-‘Arab Spring’ reality....

  6. Introduction to cosmology

    CERN Document Server

    Roos, Matts

    2015-01-01

    The Fourth Edition of Introduction to Cosmology provides a concise, authoritative study of cosmology at an introductory level. Starting from elementary principles and the early history of cosmology, the text carefully guides the student on to curved spacetimes, special and general relativity, gravitational lensing, the thermal history of the Universe, and cosmological models, including extended gravity models, black holes and Hawking's recent conjectures on the not-so-black holes.

  7. Introduction to group theory

    Directory of Open Access Journals (Sweden)

    Canals B.

    2012-03-01

    Full Text Available This chapter is a concise mathematical introduction into the algebra of groups. It is build up in the way that definitions are followed by propositions and proofs. The concepts and the terminology introduced here will serve as a basis for the following chapters that deal with group theory in the stricter sense and its application to problems in physics. The mathematical prerequisites are at the bachelor level.1

  8. Introduction to superstring theory

    International Nuclear Information System (INIS)

    Nunez, Carmen

    2009-01-01

    This is a very basic introduction to the AdS/CFT correspondence. The first lecture motivates the duality between gauge theories and gravity/string theories. The next two lectures introduce the bosonic and supersymmetric string theories. The fourth lecture is devoted to study Dp-branes and finally, in the fifth lecture I discuss the two worlds: N=4 SYM in 3+1 flat dimensions and type IIB superstrings in AdS 5 x S5. (author)

  9. Introduction to reversible computing

    CERN Document Server

    Perumalla, Kalyan S

    2013-01-01

    Few books comprehensively cover the software and programming aspects of reversible computing. Filling this gap, Introduction to Reversible Computing offers an expanded view of the field that includes the traditional energy-motivated hardware viewpoint as well as the emerging application-motivated software approach. Collecting scattered knowledge into one coherent account, the book provides a compendium of both classical and recently developed results on reversible computing. It explores up-and-coming theories, techniques, and tools for the application of rever

  10. Introduction to contact mechanics

    CERN Document Server

    Fischer-Cripps, Anthony C

    2000-01-01

    Contact mechanics deals with the elastic or plastic contact between two solid objects, and is thus intimately connected with such topics as fracture, hardness, and elasticity.This text, intended for advanced undergraduates, begins with an introduction to the mechanical properties of materials, general fracture mechanics, and fractures in brittle solids.This is followed by a detailed discussion of stresses and the nature of elastic and elastic-plastic contact.

  11. Introduction to minimax

    CERN Document Server

    Dem'yanov, V F; Louvish, D

    2014-01-01

    This user-friendly text offers a thorough introduction to the part of optimization theory that lies between approximation theory and mathematical programming, both linear and nonlinear. Written by two distinguished mathematicians, the expert treatment covers the essentials, incorporating important background materials, examples, and extensive notes.Geared toward advanced undergraduate and graduate students of mathematical programming, the text explores best approximation by algebraic polynomials in both discrete and continuous cases; the discrete problem, with and without constraints; the gene

  12. Introduction to Feynman diagrams

    CERN Document Server

    Bilenky, Samoil Mikhelevich

    1974-01-01

    Introduction to Feynman Diagrams provides Feynman diagram techniques and methods for calculating quantities measured experimentally. The book discusses topics Feynman diagrams intended for experimental physicists. Topics presented include methods for calculating the matrix elements (by perturbation theory) and the basic rules for constructing Feynman diagrams; techniques for calculating cross sections and polarizations; processes in which both leptons and hadrons take part; and the electromagnetic and weak form factors of nucleons. Experimental physicists and graduate students of physics will

  13. Combinatorics an introduction

    CERN Document Server

    Faticoni, Theodore G

    2014-01-01

    Bridges combinatorics and probability and uniquely includes detailed formulas and proofs to promote mathematical thinking Combinatorics: An Introduction introduces readers to counting combinatorics, offers examples that feature unique approaches and ideas, and presents case-by-case methods for solving problems. Detailing how combinatorial problems arise in many areas of pure mathematics, most notably in algebra, probability theory, topology, and geometry, this book provides discussion on logic and paradoxes; sets and set notations; power sets and their cardinality; Venn diagrams; the multip

  14. Introduction to Extra Dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Rizzo, Thomas G.; /SLAC

    2010-04-29

    Extra dimensions provide a very useful tool in addressing a number of the fundamental problems faced by the Standard Model. The following provides a very basic introduction to this very broad subject area as given at the VIII School of the Gravitational and Mathematical Physics Division of the Mexican Physical Society in December 2009. Some prospects for extra dimensional searches at the 7 TeV LHC with {approx}1 fb{sup -1} of integrated luminosity are provided.

  15. Introduction to superstring theory

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, Carmen [Instituto de Astronomia y Fisica del Espacio, Buenos Aires (Argentina)], e-mail: carmen@iafe.uba.ar

    2009-07-01

    This is a very basic introduction to the AdS/CFT correspondence. The first lecture motivates the duality between gauge theories and gravity/string theories. The next two lectures introduce the bosonic and supersymmetric string theories. The fourth lecture is devoted to study Dp-branes and finally, in the fifth lecture I discuss the two worlds: N=4 SYM in 3+1 flat dimensions and type IIB superstrings in AdS{sub 5} x S5. (author)

  16. Introduction to nanotheranostics

    CERN Document Server

    Tamil Selvan, Subramanian

    2016-01-01

    This book offers readers an introduction to the current status of nanoparticles and other nanomaterials that have potential applications in theranostics. Above all, it highlights the diagnostic and therapeutic applications of metallic (e.g. Au, Ag), semiconducting quantum dots (e.g. CdSe, CdTe), magnetic (e.g. Fe3O4, FePt, Co), and multifunctional (combination of two or three) nanoparticles. .

  17. Introduction to biomechatronics

    CERN Document Server

    Brooker, Graham

    2012-01-01

    Introduction to Biomechatronics provides fundamental knowledge of mechanical and electronic (mechatronic) components and systems and their interaction with human biology to assist or replace limbs, senses, and even organs damaged by trauma, birth defects, or disease. The first half of the book provides the engineering background to understand all the components of a biomechatronic system: the human subject, stimulus or actuation, transducers and sensors, signal conditioning elements, recording and display, and feedback elements.

  18. Introduction to electronics

    CERN Document Server

    Korneff, Theodore

    1966-01-01

    Introduction to Electronics focuses on the study of electronics and electronic devices. Composed of 14 chapters, the book starts with discussions on dc circuits, including resistance, voltmeter, ammeter, galvanometer, internal resistance, and positive and negative currents. This topic is followed by discussions on ac circuits, particularly addressing voltage and current, average power, resistive load, complex plane, and parallel circuits. Discussions also focus on filters and tuned circuits, diodes, and power supplies. Particularly given attention are the processes, diagrams, and analyses

  19. Introduction to Accelerators Physics

    International Nuclear Information System (INIS)

    Variola, A.

    2007-01-01

    This short course aims at giving to high energy physics students a preliminary introduction to accelerators basics. The arguments and the style were selected in this perspective. Consequently, topics such as the definition of beam parameters and luminosity were preferred to much more technical aspects. The calculation details were neglected to allow more important highlights on concepts and definitions. Some examples and exercises were suggested to summarize the different topics of the lessons

  20. Introduction to parallel programming

    CERN Document Server

    Brawer, Steven

    1989-01-01

    Introduction to Parallel Programming focuses on the techniques, processes, methodologies, and approaches involved in parallel programming. The book first offers information on Fortran, hardware and operating system models, and processes, shared memory, and simple parallel programs. Discussions focus on processes and processors, joining processes, shared memory, time-sharing with multiple processors, hardware, loops, passing arguments in function/subroutine calls, program structure, and arithmetic expressions. The text then elaborates on basic parallel programming techniques, barriers and race

  1. Introduction to Plasma Physics

    Science.gov (United States)

    Gurnett, Donald A.; Bhattacharjee, Amitava

    2017-03-01

    Preface; 1. Introduction; 2. Characteristic parameters of a plasma; 3. Single particle motions; 4. Waves in a cold plasma; 5. Kinetic theory and the moment equations; 6. Magnetohydrodynamics; 7. MHD equilibria and stability; 8. Discontinuities and shock waves; 9. Electrostatic waves in a hot unmagnetized plasma; 10. Waves in a hot magnetized plasma; 11. Nonlinear effects; 12. Collisional processes; Appendix A. Symbols; Appendix B. Useful trigonometric identities; Appendix C. Vector differential operators; Appendix D. Vector calculus identities; Index.

  2. Introduction to neutron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, W E [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1996-11-01

    We give here an introduction to the theoretical principles of neutron scattering. The relationship between scattering- and correlation-functions is particularly emphasized. Within the framework of linear response theory (justified by the weakness of the basic interaction) the relation between fluctuation and dissipation is discussed. This general framework explains the particular power of neutron scattering as an experimental method. (author) 4 figs., 4 refs.

  3. Semiconductor Manufacturing equipment introduction

    International Nuclear Information System (INIS)

    Im, Jong Sun

    2001-02-01

    This book deals with semiconductor manufacturing equipment. It is comprised of nine chapters, which are manufacturing process of semiconductor device, history of semiconductor manufacturing equipment, kinds and role of semiconductor manufacturing equipment, construction and method of semiconductor manufacturing equipment, introduction of various semiconductor manufacturing equipment, spots of semiconductor manufacturing, technical elements of semiconductor manufacturing equipment, road map of technology of semiconductor manufacturing equipment and semiconductor manufacturing equipment in the 21st century.

  4. Introduction to heat transfer

    CERN Document Server

    SUNDÉN, B

    2012-01-01

    Presenting the basic mechanisms for transfer of heat, Introduction to Heat Transfer gives a deeper and more comprehensive view than existing titles on the subject. Derivation and presentation of analytical and empirical methods are provided for calculation of heat transfer rates and temperature fields as well as pressure drop. The book covers thermal conduction, forced and natural laminar and turbulent convective heat transfer, thermal radiation including participating media, condensation, evaporation and heat exchangers.

  5. Accounting Applications---Introduction

    OpenAIRE

    Joshua Ronen

    1980-01-01

    Introduction to special issue on accounting applications. By publishing these papers together in one issue of Management Science we wish to accomplish the dual purpose of exposing management scientists to the application of their discipline to important accounting problems and of allowing management scientists and accountants to interact in areas of research and problem-solving, thus stimulating the interest of readers who are concerned with the problems of accounting.

  6. Introduction: Righting Feminism

    OpenAIRE

    Farris, Sara R.

    2017-01-01

    This is the introduction to a special issue on Righting Feminism. In recent years, we have witnessed the multifarious ways in which feminism as an emancipatory project dedicated to women's liberation has increasingly “converged” with non-emancipatory/racist, conservative, and neo-liberal economic and political agendas. Today, feminist themes are not only being "mainstreamed" but are also increasingly being mobilized to bolster existing power hierarchies as well as neo-liberal and right-wing x...

  7. Introduction: Persistent Modelling

    DEFF Research Database (Denmark)

    Ayres, Phil

    2012-01-01

    This introduction to 'Persistent Modelling – an extended role for architectural representation' identifies how the book probes the relationship between representation and the represented, in an architectural context. It discusses how the book presents an examination and discussion of historical......, familiar contemporary and, perhaps, not so familiar emerging manifestations of this relation. What persists from this probing, fully intact, is that representation and the represented remain inextricably related in our contemporary and emerging practices. What comes into focus is that the nature...

  8. Ion implantation - an introduction

    International Nuclear Information System (INIS)

    Townsend, P.D.

    1986-01-01

    Ion implantation is a widely used technique with a literature that covers semiconductor production, surface treatments of steels, corrosion resistance, catalysis and integrated optics. This brief introduction outlines advantages of the technique, some aspects of the underlying physics and examples of current applications. Ion implantation is already an essential part of semiconductor technology while in many other areas it is still in an early stage of development. The future scope of the subject is discussed. (author)

  9. Introduction to analytical mechanics

    CERN Document Server

    Gamalath, KAILW

    2011-01-01

    INTRODUCTION TO ANALYTICAL MECHANICS is an attempt to introduce the modern treatment of classical mechanics so that transition to many fields in physics can be made with the least difficulty. This book deal with the formulation of Newtonian mechanics, Lagrangian dynamics, conservation laws relating to symmetries, Hamiltonian dynamics Hamilton's principle, Poisson brackets, canonical transformations which are invaluable in formulating the quantum mechanics and Hamilton-Jacobi equation which provides the transition to wave mechanics.

  10. Introduction to QCD

    OpenAIRE

    Skands, Peter

    2012-01-01

    These lectures were originally given at TASI and are directed at a level suitable for graduate students in High Energy Physics. They are intended to give an introduction to the theory and phenomenology of quantum chromodynamics (QCD), focusing on collider physics applications. The aim is to bring the reader to a level where informed decisions can be made concerning different approaches and their uncertainties. The material is divided into five main areas: 1) fundamentals, 2) fixed-order pertu...

  11. Introduction to Q

    International Nuclear Information System (INIS)

    Kellogg, M.; Minor, M.M.; Shlaer, S.; Spencer, N.; Thomas, R.F. Jr.; van der Beken, H.

    1978-06-01

    This manual presents an overview of the Q data-acquisition system. Its purposes are to assist an experimenter in determining whether the system is suited to his needs and to provide an introduction to the more detailed manuals. This system employs a powerful technique for dealing with multiprocessor systems by generating code and communication protocol for two processors from a single source program in a high-level language. Some details of experimental event buffering and distribution are discussed

  12. Introduction to abstract algebra

    CERN Document Server

    Nicholson, W Keith

    2012-01-01

    Praise for the Third Edition ". . . an expository masterpiece of the highest didactic value that has gained additional attractivity through the various improvements . . ."-Zentralblatt MATH The Fourth Edition of Introduction to Abstract Algebra continues to provide an accessible approach to the basic structures of abstract algebra: groups, rings, and fields. The book's unique presentation helps readers advance to abstract theory by presenting concrete examples of induction, number theory, integers modulo n, and permutations before the abstract structures are defined. Readers can immediately be

  13. Introduction to microfabrication

    CERN Document Server

    Franssila, Sami

    2005-01-01

    Microfabrication is the key technology behind integrated circuits, microsensors, photonic crystals, ink jet printers, solar cells and flat panel displays. Microsystems can be complex, but the basic microstructures and processes of microfabrication are fairly simple. Introduction to Microfabrication shows how the common microfabrication concepts can be applied over and over again to create devices with a wide variety of structures and functions.Featuring:* A comprehensive presentation of basic fabrication processes* An emphasis on materials and microstructures, rather than devic

  14. Perforate on CHO cell membranes induced by electromagnetic ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-06-17

    Jun 17, 2009 ... Key words: Electromagnetic pulse (EMP), atomic force microscope, CHO cell, cell membrane. INTRODUCTION .... of perforation ranges from 390 to 660 nm and the depth is. 392.95 nm. ... cell membrane perforations increased when both the field intensity and ..... Melatonin and a spin-trap compound block.

  15. Tympanic membrane temperature decreases during head up tilt

    DEFF Research Database (Denmark)

    Lorr, David; Lund, Anton; Fredrikson, Mats

    2017-01-01

    INTRODUCTION: Changes in blood flow influence temperature of surrounding tissues. Since the internal carotid artery (ICA) and internal jugular vein (IJV) neighbor the tympanic membrane, changes in their blood flow most likely determine changes in tympanic membrane temperature (TMT). We sought to ...

  16. Two-dimensional membranes in motion

    NARCIS (Netherlands)

    Davidovikj, D.

    2018-01-01

    This thesis revolves around nanomechanical membranes made of suspended two - dimensional materials. Chapters 1-3 give an introduction to the field of 2D-based nanomechanical devices together with an overview of the underlying physics and the measurementtools used in subsequent chapters. The research

  17. A practical introduction to electroweak radiative corrections

    International Nuclear Information System (INIS)

    Drees, M.

    1991-05-01

    This is a brief introduction into electroweak radiative corrections within the Standard Model, with the emphasis on performing actual calculations. To this end, a complete set of expressions is given that allows the computation of the ρ parameter, the W mass, and Z→fanti f decays for massless fermions, where the anti Manti S scheme has been used. I conclude with an assessment of what we have learned so far from electroweak precision experiments, and a brief outlook. (orig.)

  18. A method for screening active components from Chinese herbs by cell membrane chromatography-offline-high performance liquid chromatography/mass spectrometry and an online statistical tool for data processing.

    Science.gov (United States)

    Cao, Yan; Wang, Shaozhan; Li, Yinghua; Chen, Xiaofei; Chen, Langdong; Wang, Dongyao; Zhu, Zhenyu; Yuan, Yongfang; Lv, Diya

    2018-03-09

    Cell membrane chromatography (CMC) has been successfully applied to screen bioactive compounds from Chinese herbs for many years, and some offline and online two-dimensional (2D) CMC-high performance liquid chromatography (HPLC) hyphenated systems have been established to perform screening assays. However, the requirement of sample preparation steps for the second-dimensional analysis in offline systems and the need for an interface device and technical expertise in the online system limit their extensive use. In the present study, an offline 2D CMC-HPLC analysis combined with the XCMS (various forms of chromatography coupled to mass spectrometry) Online statistical tool for data processing was established. First, our previously reported online 2D screening system was used to analyze three Chinese herbs that were reported to have potential anti-inflammatory effects, and two binding components were identified. By contrast, the proposed offline 2D screening method with XCMS Online analysis was applied, and three more ingredients were discovered in addition to the two compounds revealed by the online system. Then, cross-validation of the three compounds was performed, and they were confirmed to be included in the online data as well, but were not identified there because of their low concentrations and lack of credible statistical approaches. Last, pharmacological experiments showed that these five ingredients could inhibit IL-6 release and IL-6 gene expression on LPS-induced RAW cells in a dose-dependent manner. Compared with previous 2D CMC screening systems, this newly developed offline 2D method needs no sample preparation steps for the second-dimensional analysis, and it is sensitive, efficient, and convenient. It will be applicable in identifying active components from Chinese herbs and practical in discovery of lead compounds derived from herbs. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Algoritmo inteligente para evaluar el impacto de la introducción masiva de cocinas de inducción; Intelligent algorithm for evaluating the impact of the introduction of mass induction

    Directory of Open Access Journals (Sweden)

    Jorge Enrique Carrión González

    2015-09-01

    Full Text Available El Ministerio de Electricidad y Energía Renovable de Ecuador (MEER está implementando el plan nacional de coccióneficiente, en el país y en la región Sur. El plan se basa en reemplazar las cocinas que usan gas licuado de petróleo (GLPpor cocinas eléctricas de inducción, estos cambios representan un aumento considerable en la demanda eléctrica delsector residencial. Los estudios de los sistemas eléctricos de distribución realizados permiten evaluar el comportamientoactual de las redes eléctricas y analizar futuros escenarios para poder determinar las mejoras de carácter técnico yorganizativo que deben introducirse. Seelaboró un algoritmo genético especializado para evaluar el efecto querepresenta en los transformadores de distribución la introducción masiva de las cocinas de inducción, con vistas aresolver el problema de un crecimiento brusco de la demanda de energía, minimizando los costos de inversión en nuevosequipos de transformación.The Ministry of Electricity and Renewable Energy of Ecuador (MEER is implement in the national plan for efficient cooking in thesouthern region and the country. The planes based on replacing kitchens using liquefied petroleum gas (LPG for induction cookers,representing an increase in electricity demanding the residential sector. Studies of electrical distribution systems made it possible toassess the current behavior of electrical networks and analyze future scenarios to determinism provident in technical and organizationalmeasures to be introduced. A genetic algorithm to evaluate the effect on distribution transformer soft he massive introduction ofinduction cookers, with view to resolving the problem of sharp growthin demand for energy while minimizing the costs of investment innew equipment was developed.

  20. Vitreous membranes used in the biogas purification

    International Nuclear Information System (INIS)

    Ortega Viera, L.; Rodriguez Munoz, S.; Fernandez Santana, E.; Martines Ramirez, Y.; Crespo Artigas, A.; Viera Gallardo, Y.

    2016-01-01

    In the present work 10 vitreous membranes with different masses of zinc oxide (ZnO(s)) and particle diameters charcoal (DPC) are used in the purification of biogas. The porosity and tortuosity of the membranes is obtained, showing the variation with respect to the composition thereof. From these structural features specific flow of H 2 S(g) is obtained which is transferred using the Fick's diffusion equation in the membranes and its value increases with increasing mass of ZnO(s). By X-ray diffraction membrane made with 3.16 g of ZnO(s) forming zinc sulfide it is shown, so we can say that the removal of H 2 S(g) occurs by a process of absorption with chemical reaction in the membranes. (Author)

  1. Introduction: Exile and Social Transformation

    Directory of Open Access Journals (Sweden)

    Paul Allatson

    2005-03-01

    Full Text Available This paper serves as an introduction to the special issue of Portal on exile and its potential to effect social change. The critical and creative discussions that follow this introduction respond to a particular set of problems. What factors permit and preclude exilic individual and communal transformation? Is there a need to rethink exilic agency in accord with local times, cultures and places, and to refocus attention on exile communal impacts on a host society? And, in a globalized epoch characterized by mass population movements across geopolitical lines, do states and national desires still have key roles to play in the production of exile? There are no straightforward answers to these questions, but all gesture toward the inadequacy of a single overarching definition or description of exile. Indeed, the process of exile has generated a great deal of debate regarding to whom the term exile applies and when. Furthermore, a number of unresolved issues recur in the extensive literature on the topic: the problematic location of exile and its definitional dependency on a home or homeland; the multivalent struggles to attain and maintain exilic voice, representation, memory, and identity on many fronts (individual, familial, communal, national, transnational; exile’s uneasy relation to modernity, the state, and globalization; and exile’s conceptual competition with other terms, such as diaspora, exodus, refugee and migrant. Intended as a selective reprise of these issues and the ways the contributors to this issue have responded to them, this introduction identifies some of the claims that have been made of exile as a space or mode of social transformation, as well as the possible limits of such claims. This article has been cited in the following: Ravn, Tine. Burmesiske flygtninge i Danmark: personlige narrativer omkring identitet, tilhørsforhold og integration. Unpublished PhD Dissertation, Aalborg Universitet, Denmark, 2009. Smith

  2. Introduction to the ROOT System

    CERN Multimedia

    CERN. Geneva

    2008-01-01

    Introduction to the ROOT data handling system. ROOT is used in some for or another by all LHC experiments and will be used by all for final data analysis. The introduction gives an overview of the system. Prerequisite knowledge: C++

  3. Introduction to Artificial Neural Networks

    DEFF Research Database (Denmark)

    Larsen, Jan

    1999-01-01

    The note addresses introduction to signal analysis and classification based on artificial feed-forward neural networks.......The note addresses introduction to signal analysis and classification based on artificial feed-forward neural networks....

  4. Human drug metabolism: an introduction

    National Research Council Canada - National Science Library

    Coleman, Michael D

    2010-01-01

    Human Drug Metabolism, An Introduction, Second Edition provides an accessible introduction to the subject and will be particularly invaluable to those who already have some understanding of the life sciences...

  5. Introduction to laser technology

    CERN Document Server

    Hitz, C Breck; Hecht, Jeff; Hitz, C Breck; John Wiley & Sons

    2001-01-01

    Electrical Engineering Introduction to Laser Technology , Third Edition. Would you like to know how a laser works, and how it can be modified for your own specific tasks? This intuitive third edition-previously published as Understanding Laser Technology , First and Second Editions-introduces engineers, scientists, technicians, and novices alike to the world of modern lasers, without delving into the mathematical details of quantum electronics. It is the only introductory text on the market today that explains the underlying physics and engineering applicable to all lasers. A unique combinatio.

  6. Introduction to applied thermodynamics

    CERN Document Server

    Helsdon, R M; Walker, G E

    1965-01-01

    Introduction to Applied Thermodynamics is an introductory text on applied thermodynamics and covers topics ranging from energy and temperature to reversibility and entropy, the first and second laws of thermodynamics, and the properties of ideal gases. Standard air cycles and the thermodynamic properties of pure substances are also discussed, together with gas compressors, combustion, and psychrometry. This volume is comprised of 16 chapters and begins with an overview of the concept of energy as well as the macroscopic and molecular approaches to thermodynamics. The following chapters focus o

  7. Introduction to cosmology

    CERN Document Server

    Roos, Matts

    2003-01-01

    The Third Edition of the hugely successful Introduction to Cosmology provides a concise, authoritative study of cosmology at an introductory level. Starting from elementary principles and the history of cosmology, the text carefully guides the student on to curved spacetimes, general relativity, black holes, cosmological models, particles and symmetries, and phase transitions. Extensively revised, this latest edition includes broader and updated coverage of distance measures, gravitational lensing and waves, dark energy and quintessence, the thermal history of the Universe, inflation,

  8. Introduction to real analysis

    CERN Document Server

    Schramm, Michael J

    2008-01-01

    This text forms a bridge between courses in calculus and real analysis. It focuses on the construction of mathematical proofs as well as their final content. Suitable for upper-level undergraduates and graduate students of real analysis, it also provides a vital reference book for advanced courses in mathematics.The four-part treatment begins with an introduction to basic logical structures and techniques of proof, including discussions of the cardinality concept and the algebraic and order structures of the real and rational number systems. Part Two presents in-depth examinations of the compl

  9. Fourier analysis an introduction

    CERN Document Server

    Stein, Elias M

    2003-01-01

    This first volume, a three-part introduction to the subject, is intended for students with a beginning knowledge of mathematical analysis who are motivated to discover the ideas that shape Fourier analysis. It begins with the simple conviction that Fourier arrived at in the early nineteenth century when studying problems in the physical sciences--that an arbitrary function can be written as an infinite sum of the most basic trigonometric functions.The first part implements this idea in terms of notions of convergence and summability of Fourier series, while highlighting applications such as th

  10. Introduction to dynamic programming

    CERN Document Server

    Cooper, Leon; Rodin, E Y

    1981-01-01

    Introduction to Dynamic Programming provides information pertinent to the fundamental aspects of dynamic programming. This book considers problems that can be quantitatively formulated and deals with mathematical models of situations or phenomena that exists in the real world.Organized into 10 chapters, this book begins with an overview of the fundamental components of any mathematical optimization model. This text then presents the details of the application of dynamic programming to variational problems. Other chapters consider the application of dynamic programming to inventory theory, Mark

  11. Introduction to modern cryptography

    CERN Document Server

    Katz, Jonathan

    2014-01-01

    Praise for the First Edition:""This book is a comprehensive, rigorous introduction to what the authors name 'modern' cryptography. … a novel approach to how cryptography is taught, replacing the older, construction-based approach. … The concepts are clearly stated, both in an intuitive fashion and formally. … I would heartily recommend this book to anyone who is interested in cryptography. … The exercises are challenging and interesting, and can benefit readers of all academic levels.""-IACR Book Reviews, January 2010""Over the past 30 years, cryptography has been transformed from a mysterious

  12. Introduction to Heat Pipes

    Science.gov (United States)

    Ku, Jentung

    2015-01-01

    This is the presentation file for the short course Introduction to Heat Pipes, to be conducted at the 2015 Thermal Fluids and Analysis Workshop, August 3-7, 2015, Silver Spring, Maryland. NCTS 21070-15. Course Description: This course will present operating principles of the heat pipe with emphases on the underlying physical processes and requirements of pressure and energy balance. Performance characterizations and design considerations of the heat pipe will be highlighted. Guidelines for thermal engineers in the selection of heat pipes as part of the spacecraft thermal control system, testing methodology, and analytical modeling will also be discussed.

  13. An introduction to optimization

    CERN Document Server

    Chong, Edwin K P

    2013-01-01

    Praise for the Third Edition "". . . guides and leads the reader through the learning path . . . [e]xamples are stated very clearly and the results are presented with attention to detail.""  -MAA Reviews  Fully updated to reflect new developments in the field, the Fourth Edition of Introduction to Optimization fills the need for accessible treatment of optimization theory and methods with an emphasis on engineering design. Basic definitions and notations are provided in addition to the related fundamental background for linear algebra, geometry, and calculus.  This new

  14. Introduction to continuum mechanics

    CERN Document Server

    Lai, W Michael; Rubin, David

    1996-01-01

    Introduction to Continuum Mechanics is a recently updated and revised text which is perfect for either introductory courses in an undergraduate engineering curriculum or for a beginning graduate course.Continuum Mechanics studies the response of materials to different loading conditions. The concept of tensors is introduced through the idea of linear transformation in a self-contained chapter, and the interrelation of direct notation, indicial notation, and matrix operations is clearly presented. A wide range of idealized materials are considered through simple static and dynamic problems, a

  15. Cartesian tensors an introduction

    CERN Document Server

    Temple, G

    2004-01-01

    This undergraduate text provides an introduction to the theory of Cartesian tensors, defining tensors as multilinear functions of direction, and simplifying many theorems in a manner that lends unity to the subject. The author notes the importance of the analysis of the structure of tensors in terms of spectral sets of projection operators as part of the very substance of quantum theory. He therefore provides an elementary discussion of the subject, in addition to a view of isotropic tensors and spinor analysis within the confines of Euclidean space. The text concludes with an examination of t

  16. Introduction to cluster dynamics

    CERN Document Server

    Reinhard, Paul-Gerhard

    2008-01-01

    Clusters as mesoscopic particles represent an intermediate state of matter between single atoms and solid material. The tendency to miniaturise technical objects requires knowledge about systems which contain a ""small"" number of atoms or molecules only. This is all the more true for dynamical aspects, particularly in relation to the qick development of laser technology and femtosecond spectroscopy. Here, for the first time is a highly qualitative introduction to cluster physics. With its emphasis on cluster dynamics, this will be vital to everyone involved in this interdisciplinary subje

  17. Introduction to superconductivity

    CERN Document Server

    Rose-Innes, A C

    1978-01-01

    Introduction to Superconductivity differs from the first edition chiefly in Chapter 11, which has been almost completely rewritten to give a more physically-based picture of the effects arising from the long-range coherence of the electron-waves in superconductors and the operation of quantum interference devices. In this revised second edition, some further modifications have been made to the text and an extra chapter dealing with """"high-temperature"""" superconductors has been added. A vast amount of research has been carried out on these since their discovery in 1986 but the results, both

  18. Introduction to information retrieval

    CERN Document Server

    Manning, Christopher D; Schütze, Hinrich

    2008-01-01

    Class-tested and coherent, this textbook teaches classical and web information retrieval, including web search and the related areas of text classification and text clustering from basic concepts. It gives an up-to-date treatment of all aspects of the design and implementation of systems for gathering, indexing, and searching documents; methods for evaluating systems; and an introduction to the use of machine learning methods on text collections. All the important ideas are explained using examples and figures, making it perfect for introductory courses in information retrieval for advanced un

  19. Introduction to Econophysics

    Science.gov (United States)

    Mantegna, Rosario N.; Stanley, H. Eugene

    2007-08-01

    Preface; 1. Introduction; 2. Efficient market hypothesis; 3. Random walk; 4. Lévy stochastic processes and limit theorems; 5. Scales in financial data; 6. Stationarity and time correlation; 7. Time correlation in financial time series; 8. Stochastic models of price dynamics; 9. Scaling and its breakdown; 10. ARCH and GARCH processes; 11. Financial markets and turbulence; 12. Correlation and anti-correlation between stocks; 13. Taxonomy of a stock portfolio; 14. Options in idealized markets; 15. Options in real markets; Appendix A: notation guide; Appendix B: martingales; References; Index.

  20. Theoretical astrophysics an introduction

    CERN Document Server

    Bartelmann, Matthias

    2013-01-01

    A concise yet comprehensive introduction to the central theoretical concepts of modern astrophysics, presenting hydrodynamics, radiation, and stellar dynamics all in one textbook. Adopting a modular structure, the author illustrates a small number of fundamental physical methods and principles, which are sufficient to describe and understand a wide range of seemingly very diverse astrophysical phenomena and processes. For example, the formulae that define the macroscopic behavior of stellar systems are all derived in the same way from the microscopic distribution function. This function it

  1. Introduction to spectral theory

    CERN Document Server

    Levitan, B M

    1975-01-01

    This monograph is devoted to the spectral theory of the Sturm- Liouville operator and to the spectral theory of the Dirac system. In addition, some results are given for nth order ordinary differential operators. Those parts of this book which concern nth order operators can serve as simply an introduction to this domain, which at the present time has already had time to become very broad. For the convenience of the reader who is not familar with abstract spectral theory, the authors have inserted a chapter (Chapter 13) in which they discuss this theory, concisely and in the main without proofs, and indicate various connections with the spectral theory of differential operators.

  2. Introduction to mathematical logic

    CERN Document Server

    Mendelson, Elliott

    2015-01-01

    The new edition of this classic textbook, Introduction to Mathematical Logic, Sixth Edition explores the principal topics of mathematical logic. It covers propositional logic, first-order logic, first-order number theory, axiomatic set theory, and the theory of computability. The text also discusses the major results of Gödel, Church, Kleene, Rosser, and Turing.The sixth edition incorporates recent work on Gödel's second incompleteness theorem as well as restoring an appendix on consistency proofs for first-order arithmetic. This appendix last appeared in the first edition. It is offered in th

  3. An introduction to cosmology

    CERN Document Server

    Narlikar, Jayant Vishnu

    2002-01-01

    The third edition of this successful textbook is fully updated and includes important recent developments in cosmology. It begins with an introduction to cosmology and general relativity, and goes on to cover the mathematical models of standard cosmology. The physical aspects of cosmology, including primordial nucleosynthesis, the astroparticle physics of inflation, and the current ideas on structure formation are discussed. Alternative models of cosmology are reviewed, including the model of Quasi-Steady State Cosmology, which has recently been proposed as an alternative to Big Bang Cosmology.

  4. Introduction to cardinal arithmetic

    CERN Document Server

    Holz, M; Weitz, E

    1999-01-01

    This book is an introduction into modern cardinal arithmetic in the frame of the axioms of Zermelo-Fraenkel set theory together with the axiom of choice (ZFC). A first part describes the classical theory developed by Bernstein, Cantor, Hausdorff, König and Tarski between 1870 and 1930. Next, the development in the 1970s led by Galvin, Hajnal and Silver is characterized. The third part presents the fundamental investigations in pcf theory which have been worked out by Shelah to answer the questions left open in the 1970s.Reviews:'The authors aim their text at beginners in set theory. They start

  5. Introduction to EMC

    CERN Document Server

    Scott, John

    1997-01-01

    This is the clear guide for non-specialists to electromagnetic compatability (EMC), the effects of electromagnetic radiation and the European EMC Directive which is now in force. This book helps by explaining the basic principles of EMC, how it may be controlled in practice through filtering, shielding, appropriate printed circuit board design, and other means. Electrostatic discharge (ESD) and surge protection are discussed. The growing concern about the effects of electromagnetic waves and fields on health are examined in detail.This introduction provides beginners, technical and

  6. Introduction to superconductivity

    CERN Document Server

    Darriulat, Pierre

    1998-01-01

    The lecture series will address physicists, such as particle and nuclear physicists, familiar with non-relativistic quantum mechanics but not with solid state physics. The aim of this introduction to low temperature superconductivity is to give sufficient bases to the student for him/her to be able to access the scientific literature on this field. The five lectures will cover the following topics : 1. Normal metals, free electron gas, chambers equation. 2. Cooper pairs, the BCS ground state, quasi particle excitations. 3. DC superconductivity, Meissner state, dirty superconductors.4. Self consistent approach, Ginsburg Landau equations, Abrikosov fluxon lattice. 5. Josephson effects, high temperature superconductivity.

  7. Introduction to combinatorial designs

    CERN Document Server

    Wallis, WD

    2007-01-01

    Combinatorial theory is one of the fastest growing areas of modern mathematics. Focusing on a major part of this subject, Introduction to Combinatorial Designs, Second Edition provides a solid foundation in the classical areas of design theory as well as in more contemporary designs based on applications in a variety of fields. After an overview of basic concepts, the text introduces balanced designs and finite geometries. The author then delves into balanced incomplete block designs, covering difference methods, residual and derived designs, and resolvability. Following a chapter on the e

  8. Statistics a biomedical introduction

    CERN Document Server

    Brown, Byron Wm

    2009-01-01

    CHAPTER 1: Introduction 1 CHAPTER 2: Elementary Rules of Probability 13 CHAPTER 3: Populations, Samples, and the Distribution of the Sample Mean 37 1. Populations and Distributions 38 2. Sampling from Finite Populations 64 3. The Distribution of the Sample Mean 72 CHAPTER 4: Analysis of Matched Pairs Using Sample Means 85 1. A Confidence Interval for the Treatment Effect 86 2. A Hypothesis Test for the Treatment Effect 96 3. Determining the Sample Size 102 CHAPTER 5: Analysis of the Two-Sample Location Problem Using Sample Means 109 1. A Confidence Interval for the Diffe

  9. Game Theory An Introduction

    CERN Document Server

    Barron, E N

    2008-01-01

    A fundamental introduction to modern game theory from a mathematical viewpoint. Game theory arises in almost every fact of human and inhuman interaction since oftentimes during these communications objectives are opposed or cooperation is viewed as an option. From economics and finance to biology and computer science, researchers and practitioners are often put in complex decision-making scenarios, whether they are interacting with each other or working with evolving technology and artificial intelligence. Acknowledging the role of mathematics in making logical and advantageous decisions, Game

  10. Introduction to laser technology

    CERN Document Server

    Hitz, C Breck; Hecht, Jeff

    2012-01-01

    The only introductory text on the market today that explains the underlying physics and engineering applicable to all lasersAlthough lasers are becoming increasingly important in our high-tech environment, many of the technicians and engineers who install, operate, and maintain them have had little, if any, formal training in the field of electro-optics. This can result in less efficient usage of these important tools. Introduction to Laser Technology, Fourth Edition provides readers with a good understanding of what a laser is and what it can and cannot do. The book explains what types of las.

  11. Introduction to differentiable manifolds

    CERN Document Server

    Auslander, Louis

    2009-01-01

    The first book to treat manifold theory at an introductory level, this text surveys basic concepts in the modern approach to differential geometry. The first six chapters define and illustrate differentiable manifolds, and the final four chapters investigate the roles of differential structures in a variety of situations.Starting with an introduction to differentiable manifolds and their tangent spaces, the text examines Euclidean spaces, their submanifolds, and abstract manifolds. Succeeding chapters explore the tangent bundle and vector fields and discuss their association with ordinary diff

  12. Introduction: Mirrors of Passing

    DEFF Research Database (Denmark)

    Seebach, Sophie Hooge; Willerslev, Rane

    How is death, time, and materiality interconnected? How to approach an understanding of the world of the dead? In this introduction, we seek to understand how the experience of material decay, of the death of those around us, makes us aware of the passing of time. Through the literary lens of Neil...... Gaiman’s The Graveyard Book, we explore how the world of the dead and the world of the living can intersect; how time and materiality shifts and changes depending on who experiences it. These revelations, based on fiction, provide a mirror through which the reader can experience the varied chapters...

  13. Introduction to functional methods

    International Nuclear Information System (INIS)

    Faddeev, L.D.

    1976-01-01

    The functional integral is considered in relation to Feynman diagrams and phase space. The holomorphic form of the functional integral is then discussed. The main problem of the lectures, viz. the construction of the S-matrix by means of the functional integral, is considered. The functional methods described explicitly take into account the Bose statistics of the fields involved. The different procedure used to treat fermions is discussed. An introduction to the problem of quantization of gauge fields is given. (B.R.H.)

  14. Abdominal imaging: An introduction

    International Nuclear Information System (INIS)

    Frick, M.P.; Feinberg, S.B.

    1986-01-01

    This nine-chapter book gives an overview of the integrated approach to abdominal imaging. Chapter 1 provides an introduction to the physics used in medical imaging; chapter 2 is on the selection of imaging modalities. These are followed by four chapters that deal, respectively, with plain radiography, computed tomographic scanning, sonography, and nuclear imaging, as applied to the abdomen. Two chapters then cover contrast material-enhanced studies of the gastrointestinal (GI) tract: one focusing on technical considerations; the other, on radiologic study of disease processes. The final chapter is a brief account of different interventional procedures

  15. Introduction to Waste Engineering

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund

    2011-01-01

    Solid waste management as introduced in Chapter 1.1 builds in many ways on engineering. Waste engineering here means the skills and ability to understand quantitatively how a waste management system works in such a detail that waste management can be planned, facilities can be designed and sited......) regional plans for waste management, including (3) the selection of main management technologies and siting of facilities, (4) the design of individual technological units and, for example, (5) the operation of recycling schemes within a municipality. This chapter gives an introduction to waste engineering...

  16. Quantum chemistry an introduction

    CERN Document Server

    Kauzmann, Walter

    2013-01-01

    Quantum Chemistry: An Introduction provides information pertinent to the fundamental aspects of quantum mechanics. This book presents the theory of partial differentiation equations by using the classical theory of vibrations as a means of developing physical insight into this essential branch of mathematics.Organized into five parts encompassing 16 chapters, this book begins with an overview of how quantum mechanical deductions are made. This text then describes the achievements and limitations of the application of quantum mechanics to chemical problems. Other chapters provide a brief survey

  17. Introduction to information science

    CERN Document Server

    Bawden, David

    2012-01-01

    This landmark textbook takes a whole subject approach to Information Science as a discipline. Introduced by leading international scholars and offering a global perspective on the discipline, this is designed to be the standard text for students worldwide. The authors' expert narrative guides you through each of the essential building blocks of information science offering a concise introduction and expertly chosen further reading and resources.Critical topics covered include:foundations: concepts, theories and historical perspectivesorganising and retrieving Information information behaviour,

  18. Introduction to data technologies

    CERN Document Server

    Murrell, Paul

    2009-01-01

    Providing key information on how to work with research data, Introduction to Data Technologies presents ideas and techniques for performing critical, behind-the-scenes tasks that take up so much time and effort yet typically receive little attention in formal education. With a focus on computational tools, the book shows readers how to improve their awareness of what tasks can be achieved and describes the correct approach to perform these tasks. Practical examples demonstrate the most important pointsThe author first discusses how to write computer code using HTML as a concrete example. He th

  19. Introduction to plasma engineering

    International Nuclear Information System (INIS)

    Roth, J.R.

    1988-01-01

    The author has begun writing a textbook entitled Introduction to Plasma Engineering, which is intended for upper division undergraduates or professionals who are entering the field. This paper features a detailed topical outline of all 20 chapters of the book. The text is organized so that the first five chapters cover plasma physics and basic principles; the next 13 chapters cover the most important engineering applications of plasmas, in order of increasing plasma energy/number density; and two final chapters cover plasma diagnostics and magnetic coil design

  20. Theoretical Optics An Introduction

    CERN Document Server

    Römer, Hartmann

    2004-01-01

    Starting from basic electrodynamics, this volume provides a solid, yet concise introduction to theoretical optics, containing topics such as nonlinear optics, light-matter interaction, and modern topics in quantum optics, including entanglement, cryptography, and quantum computation. The author, with many years of experience in teaching and research, goes way beyond the scope of traditional lectures, enabling readers to keep up with the current state of knowledge. Both content and presentation make it essential reading for graduate and phD students as well as a valuable reference for researche

  1. History as Modernity. Introduction

    Directory of Open Access Journals (Sweden)

    Pierangelo Schiera

    2016-12-01

    Full Text Available The introduction starts from the exhaustion of modernity, drawing the fundamental lines of its development inside Western historical experience. The end of the political nexus between theology and politics, the evanescence of nation-state sovereignty, the check of great historical interpretations reveal the necessity of new categories and new organizational models, able to make us answer to the violence that the ongoing processes are liberating. Schiera underlines in particular the relevance of the administrative apparatus because of its capacity to link the global government with global organization, human rights and the commons.

  2. The off-shell closed strings as the topological open membranes. Dynamical transmutation of world sheet dimension

    International Nuclear Information System (INIS)

    Kogan, Y.I.

    1989-05-01

    Using the connection between (2+1) Chern-Simons gauge theory and 2d Conformal Field Theory the on-shell string condition is obtained as a condition of full independence of interior of (2+1) world. The new method for off-shell continuation is considered based on the introduction of the Maxwell term in (2+1) theory. This leads to dynamical transmutation of world-sheet dimensions - the off-shell string becomes topological membrane (topological means that (2+1) theory has topological mass term). The dependence of parameters of (2+1) theory under the external fields is discussed. (author). 17 refs

  3. Les techniques de séparation de gaz par membranes Gas Separation Techniques by Membranes

    Directory of Open Access Journals (Sweden)

    Avrillon R.

    2006-11-01

    Full Text Available Deux types de membranes peuvent être utilisés pour la séparation des gaz. Les unes sont poreuses et séparent les gaz sur la base de leur masse moléculaire selon un mécanisme de diffusion de Knudsen dans des micropores. Les facteurs de séparation obtenus sont généralement trop faibles pour présenter un intérêt industriel. Les autres, appelées membranes non poreuses, mettent en oeuvre un mécanisme de dissolution-diffusion des gaz dans une fine couche de polymère dénuée de toute porosité. C'est de ces dernières que nous allons parler. Commencé il y a une vingtaine d'années, le développement de ce type de membranes a conduit aux premières applications industrielles en 1979 avec l'introduction par Monsanto des séparateurs PRISM pour la récupération d'hydrogène à partir de différents gaz de raffinerie et de pétrochimie. Après des débuts modestes par suite de la compétition avec des technologies éprouvées comme la cryogénie, l'adsorption et l'absorption, la perméation gazeuse est en train de conquérir sa place parmi les techniques de séparation de gaz. Elle est aujourd'hui l'une des techniques membranaires présentant le plus fort taux de progression (30 % par an. Après un rappel des principes de base de la perméation gazeuse on abordera successivement les points suivants : - le choix du polymère constituant la couche séparatrice, - l'élaboration des membranes à structure asymétrique présentant une peau dense et fine, - les principales applications industrielles. Cela permettra de mettre en évidence les avantages et les limitations actuelles de la perméation gazeuse et de souligner les différents domaines où les efforts de R et D peuvent amener des progrès significatifs. Principle of Gas permeation - Gas permeation is a technique for fractionating gas mixtures by using nonporous polymer membranes having a selective permeability to gas according to a dissolution-diffusion mechanism. Gas is made to pass

  4. Robotic membranes

    DEFF Research Database (Denmark)

    Ramsgaard Thomsen, Mette

    2008-01-01

    The relationship between digital and analogue is often constructed as one of opposition. The perception that the world is permeated with underlying patterns of data, describing events and matter alike, suggests that information can be understood apart from the substance to which it is associated......, and that its encoded logic can be constructed and reconfigured as an isolated entity. This disembodiment of information from materiality implies that an event like a thunderstorm, or a material like a body, can be described equally by data, in other words it can be read or written. The following prototypes......, Vivisection and Strange Metabolisms, were developed at the Centre for Information Technology and Architecture (CITA) at the Royal Danish Academy of Fine Arts in Copenhagen as a means of engaging intangible digital data with tactile physical material. As robotic membranes, they are a dual examination...

  5. Fourier Transform Mass Spectrometry

    Science.gov (United States)

    Scigelova, Michaela; Hornshaw, Martin; Giannakopulos, Anastassios; Makarov, Alexander

    2011-01-01

    This article provides an introduction to Fourier transform-based mass spectrometry. The key performance characteristics of Fourier transform-based mass spectrometry, mass accuracy and resolution, are presented in the view of how they impact the interpretation of measurements in proteomic applications. The theory and principles of operation of two types of mass analyzer, Fourier transform ion cyclotron resonance and Orbitrap, are described. Major benefits as well as limitations of Fourier transform-based mass spectrometry technology are discussed in the context of practical sample analysis, and illustrated with examples included as figures in this text and in the accompanying slide set. Comparisons highlighting the performance differences between the two mass analyzers are made where deemed useful in assisting the user with choosing the most appropriate technology for an application. Recent developments of these high-performing mass spectrometers are mentioned to provide a future outlook. PMID:21742802

  6. Introduction to bioinformatics.

    Science.gov (United States)

    Can, Tolga

    2014-01-01

    Bioinformatics is an interdisciplinary field mainly involving molecular biology and genetics, computer science, mathematics, and statistics. Data intensive, large-scale biological problems are addressed from a computational point of view. The most common problems are modeling biological processes at the molecular level and making inferences from collected data. A bioinformatics solution usually involves the following steps: Collect statistics from biological data. Build a computational model. Solve a computational modeling problem. Test and evaluate a computational algorithm. This chapter gives a brief introduction to bioinformatics by first providing an introduction to biological terminology and then discussing some classical bioinformatics problems organized by the types of data sources. Sequence analysis is the analysis of DNA and protein sequences for clues regarding function and includes subproblems such as identification of homologs, multiple sequence alignment, searching sequence patterns, and evolutionary analyses. Protein structures are three-dimensional data and the associated problems are structure prediction (secondary and tertiary), analysis of protein structures for clues regarding function, and structural alignment. Gene expression data is usually represented as matrices and analysis of microarray data mostly involves statistics analysis, classification, and clustering approaches. Biological networks such as gene regulatory networks, metabolic pathways, and protein-protein interaction networks are usually modeled as graphs and graph theoretic approaches are used to solve associated problems such as construction and analysis of large-scale networks.

  7. Introduction to nonlinear acoustics

    Science.gov (United States)

    Bjørnø, Leif

    2010-01-01

    A brief review of the basic principles of fluid mechanics needed for development of linear and nonlinear ultrasonic concepts will be given. The fundamental equations of nonlinear ultrasonics will be derived and their physical properties explained. It will be shown how an originally monochromatic finite-amplitude ultrasonic wave, due to nonlinear effects, will distort during its propagation in time and space to form higher harmonics to its fundamental frequency. The concepts of shock formation will be presented. The material nonlinearity, described by the nonlinearity parameter B/A of the material, and the convective nonlinearity, described by the ultrasonic Mach Number, will be explained. Two procedures for determination of B/A will briefly be described and some B/A-values characterizing biological materials will be presented. Shock formation, described by use of the Goldberg Number,and Ultrasonic Saturation will be discussed.. An introduction to focused ultrasonic fields will be given and it will be shown how the ultrasonic intensity will vary axially and laterally in and near the focal region and how the field parameters of interest to biomedical applications may be described by use of the KZK-Model. Finally, an introduction will be given to the parametric acoustic array formed by mixing and interaction of two monochromatic, finite-amplitude ultrasonic waves in a liquid and the potentials of this mixing process in biomedical ultrasound will briefly be mentioned.

  8. Change of properties of erythrocytes membranes in UV-irradiated blood

    International Nuclear Information System (INIS)

    Gromov, A.E.; Vetosh, A.N.; Nikonchuk, N.P.; Perelygin, V.G.; Ruzanov, I.B.

    1986-01-01

    An increase in erythrocyte membrane permeability for gases, decrease in erythrocyte thermal stability and activation of membrane transport systems after autotransfusion of UV-irradiated blood are ascertained. The data obtained testify to the fact that the greatest changes in membranes take place not directly under irradiation but after the introduction of irradiated blood to the organism

  9. Advances in Membrane Distillation for Water Desalination and Purification Applications

    Directory of Open Access Journals (Sweden)

    Juan Gomez

    2013-01-01

    Full Text Available Membrane distillation is a process that utilizes differences in vapor pressure to permeate water through a macro-porous membrane and reject other non-volatile constituents present in the influent water. This review considers the fundamental heat and mass transfer processes in membrane distillation, recent advances in membrane technology, module configurations, and the applications and economics of membrane distillation, and identifies areas that may lead to technological improvements in membrane distillation as well as the application characteristics required for commercial deployment.

  10. Effect of the Human Amniotic Membrane on Liver Regeneration in Rats

    Directory of Open Access Journals (Sweden)

    Mesut Sipahi

    2015-01-01

    Full Text Available Introduction. Operations are performed for broader liver surgery indications for a better understanding of hepatic anatomy/physiology and developments in operation technology. Surgery can cure some patients with liver metastasis of some tumors. Nevertheless, postoperative liver failure is the most feared complication causing mortality in patients who have undergone excision of a large liver mass. The human amniotic membrane has regenerative effects. Thus, we investigated the effects of the human amniotic membrane on regeneration of the resected liver. Methods. Twenty female Wistar albino rats were divided into control and experimental groups and underwent a 70% hepatectomy. The human amniotic membrane was placed over the residual liver in the experimental group. Relative liver weight, histopathological features, and biochemical parameters were assessed on postoperative day 3. Results. Total protein and albumin levels were significantly lower in the experimental group than in the control group. No difference in relative liver weight was observed between the groups. Hepatocyte mitotic count was significantly higher in the experimental group than in the control group. Hepatic steatosis was detected in the experimental group. Conclusion. Applying the amniotic membrane to residual liver adversely affected liver regeneration. However, mesenchymal stem cell research has the potential to accelerate liver regeneration investigations.

  11. Introduction to massive neutrinos

    International Nuclear Information System (INIS)

    Kayser, B.

    1984-01-01

    We discuss the theoretical ideas which make it natural to expect that neutrinos do indeed have mass. Then we focus on the physical consequences of neutrino mass, including neutrino oscillation and other phenomena whose observation would be very interesting, and would serve to demonstrate that neutrinos are indeed massive. We comment on the legitimacy of comparing results from different types of experiments. Finally, we consider the question of whether neutrinos are their own antiparticles. We explain what this question means, discuss the nature of a neutrino which is its own antiparticles, and consider how one might determine experimentally whether neutrinos are their own antiparticles or not

  12. Introduction to Computational Plasticity

    International Nuclear Information System (INIS)

    Hartley, P

    2006-01-01

    The focus of the book on computational plasticity embodies techniques of relevance not only to academic researchers, but also of interest to industrialists engaged in the production of components using bulk or sheet forming processes. Of particular interest is the guidance on how to create modules for use with the commercial system Abaqus for specific types of material behaviour. The book is in two parts, the first of which contains six chapters, starting with microplasticity, but predominantly on continuum plasticity. The first chapter on microplasticty gives a brief description of the grain structure of metals and the existence of slip systems within the grains. This provides an introduction to the concept of incompressibility during plastic deformation, the nature of plastic yield and the importance of the critically resolved shear stress on the slip planes (Schmid's law). Some knowledge of the notation commonly used to describe slip systems is assumed, which will be familiar to students of metallurgy, but anyone with a more general engineering background may need to undertake additional reading to understand the various descriptions. Chapter two introduces one of several yield criteria, that normally attributed to von Mises (though historians of mechanics might argue over who was first to develop the theory of yielding associated with strain energy density), and its two or three-dimensional representation as a yield surface. The expansion of the yield surface during plastic deformation, its translation due to kinematic hardening and the Bauschinger effect in reversed loading are described with a direct link to the material stress-strain curve. The assumption, that the increment of strain is normal to the yield surface, the normality principle, is introduced. Uniaxial loading of an elastic-plastic material is used as an example in which to develop expressions to describe increments in stress and strain. The full presentation of numerous expressions, tensors and

  13. Optimization of collision/reaction gases for determination of 90Sr in atmospheric particulate matter by inductively coupled plasma tandem mass spectrometry after direct introduction of air via a gas-exchange device

    Science.gov (United States)

    Suzuki, Yoshinari; Ohara, Ryota; Matsunaga, Kirara

    2017-09-01

    Nuclear power plant accidents release radioactive strontium 90 (90Sr) into the environment. Monitoring of 90Sr, although important, is difficult and time consuming because it emits only beta radiation. We have developed a new analytical system that enables real-time analysis of 90Sr in atmospheric particulate matter with an analytical run time of only 10 min. Briefly, after passage of an air sample through an impactor, a small fraction of the sample is introduced into a gas-exchange device, where the air is replaced by Ar. Then the sample is directly introduced into an inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) system equipped with a collision/reaction cell to eliminate isobaric interferences on 90Sr from 90Zr+, 89Y1H+, and 90Y+. Experiments with various reaction gas conditions revealed that these interferences could be minimized under the following optimized conditions: 1.0 mL min- 1 O2, 10.0 mL min- 1 H2, and 1.0 mL min- 1 NH3. The estimated background equivalent concentration and estimated detection limit of the system were 9.7 × 10- 4 and 3.6 × 10- 4 ng m- 3, respectively, which are equivalent to 4.9 × 10- 6 and 1.8 × 10- 6 Bq cm- 3. Recoveries of Sr in PM2.5 measured by real-time analysis compared to those obtained by simultaneously collection on filter was 53 ± 23%, and using this recovery, the detection limit as PM2.5 was estimated to be 3.4 ± 1.5 × 10- 6 Bq cm- 3. That is, this system enabled detection of 90Sr at concentrations < 5 × 10- 6 Bq cm- 3 even considering the insufficient fusion/vaporization/ionization efficiency of Sr in PM2.5.

  14. Biophysics An Introduction

    CERN Document Server

    Glaser, Roland

    2012-01-01

    Biophysics is the science of physical principles underlying all processes of life, including the dynamics and kinetics of biological systems. This fully revised 2nd English edition is an introductory text that spans all steps of biological organization, from the molecular, to the organism level, as well as influences of environmental factors. In response to the enormous progress recently made, especially in theoretical and molecular biophysics, the author has updated the text, integrating new results and developments concerning protein folding and dynamics, molecular aspects of membrane assembly and transport, noise-enhanced processes, and photo-biophysics. The advances made in theoretical biology in the last decade call for a fully new conception of the corresponding sections. Thus, the book provides the background needed for fundamental training in biophysics and, in addition, offers a great deal of advanced biophysical knowledge.

  15. Introduction to gauge theories

    International Nuclear Information System (INIS)

    Wit, B. de

    1983-01-01

    In these lectures we present the key ingredients of theories with local gauge invariance. We introduce gauge invariance as a starting point for the construction of a certain class of field theories, both for abelian and nonabelian gauge groups. General implications of gauge invariance are discussed, and we outline in detail how gauge fields can acquire masses in a spontaneous fashion. (orig./HSI)

  16. Introduction Materials and Methods

    African Journals Online (AJOL)

    satisfies the Wilson's criteria for a screening test for breast masses 9. ... half of the sample 43 (49.4%) had clinical diagnosis of breast cancer. The study found that, the .... compounds the problem of carcinoma of the breast in postmenopausal ...

  17. Morbillivirus Infections: An Introduction

    Directory of Open Access Journals (Sweden)

    Rory D. de Vries

    2015-02-01

    Full Text Available Research on morbillivirus infections has led to exciting developments in recent years. Global measles vaccination coverage has increased, resulting in a significant reduction in measles mortality. In 2011 rinderpest virus was declared globally eradicated – only the second virus to be eradicated by targeted vaccination. Identification of new cellular receptors and implementation of recombinant viruses expressing fluorescent proteins in a range of model systems have provided fundamental new insights into the pathogenesis of morbilliviruses, and their interactions with the host immune system. Nevertheless, both new and well-studied morbilliviruses are associated with significant disease in wildlife and domestic animals. This illustrates the need for robust surveillance and a strategic focus on barriers that restrict cross-species transmission. Recent and ongoing measles outbreaks also demonstrate that maintenance of high vaccination coverage for these highly infectious agents is critical. This introduction briefly summarizes the most important current research topics in this field.

  18. Nuclear reactors. Introduction

    International Nuclear Information System (INIS)

    Boiron, P.

    1997-01-01

    This paper is an introduction to the 'nuclear reactors' volume of the Engineers Techniques collection. It gives a general presentation of the different articles of the volume which deal with: the physical basis (neutron physics and ionizing radiations-matter interactions, neutron moderation and diffusion), the basic concepts and functioning of nuclear reactors (possible fuel-moderator-coolant-structure combinations, research and materials testing reactors, reactors theory and neutron characteristics, neutron calculations for reactor cores, thermo-hydraulics, fluid-structure interactions and thermomechanical behaviour of fuels in PWRs and fast breeder reactors, thermal and mechanical effects on reactors structure), the industrial reactors (light water, pressurized water, boiling water, graphite moderated, fast breeder, high temperature and heavy water reactors), and the technology of PWRs (conceiving and building rules, nuclear parks and safety, reactor components and site selection). (J.S.)

  19. Introduction and Overview

    International Nuclear Information System (INIS)

    Mathews, J.T.

    1991-01-01

    The author introduces a collection of papers by US scientists concerned with the need for a regime to control global warming. The papers were prepared in the interest of stimulating the widest possible consideration of the choices that may be faced at the United Nations Conference on Environment and Development in June of 1992. Several papers present the argument that a climate regime will take the form of a general framework convention followed by implementing protocols, following the model of the Vienna convention and its subsequent Montreal protocol. Subsequent papers shift the focus from the form of specific agreements to the continuing process of which treaties are a part. The author follows this introduction with her own viewpoint of strategies for a regime to control greenhouse warming

  20. Introduction to dynamics

    CERN Document Server

    Pfeiffer, Friedrich

    2015-01-01

    This concise textbook for students preferably of a postgraduate level, but also for engineers in practice, contains the basic kinematical and kinetic structures of dynamics together with carefully selected applications. The book is a condensed introduction to the fundamental laws of kinematics and kinetics, on the most important principles of mechanics and presents the equations of motion in the form of Lagrange and Newton-Euler. Selected problems of linear and nonlinear dynamics are treated, as well as problems of vibration formation. The presented selection of topics gives a useful basis for stepping into more advanced problems of dynamics. The contents of this book represent the result of a regularly revised course, which has been and still is given for masters students at the Technische Universität München. .

  1. Introduction to computer ethics

    Directory of Open Access Journals (Sweden)

    Ćorić Dragana M.

    2015-01-01

    Full Text Available Ethics is becoming one of the most often used but also misinter­preted words. It is often taken as an additional, corrective parameter to the policies and strategies that has to be adopted in the area of political works, environment, business, and medicine. Computer ethics thus makes the latest ethical discipline in the scientific sky. But its roots, as it was the case with environmental ethics, ranging decades; only the speech and the use of the same, as well as discussions on the postulates of computer ethics, are the results of rapid IT development in the last decade or two. In this paper, according to the title, will be shown introduction to computer ethics-its basis, the most important representatives, as well as the most important succession.

  2. Solar energy an introduction

    CERN Document Server

    Mackay, Michael E

    2015-01-01

    Solar Energy presents an introduction to all aspects of solar energy, from photovoltaic devices to active and passive solar thermal energy conversion, giving both a detailed and broad perspective of the field. It is aimed at the beginner involved in solar energy or a related field, or for someone wanting to gain a broader perspective of solar energy technologies. A chapter considering solar radiation, basic principles applied to solar energy, semiconductor physics, and light absorption brings the reader on equal footing with the technology of either solar generated electrical current or useful heat. Details of how a solar cell works and then production of current from a photovoltaic device is discussed. Characterization of a solar cell is examined, allowing one the ability to interpret the current-voltage relation, followed by discussion of parameter extraction from this relation. This information can be used to understand what limits the performance of a given solar cell with the potential to optimize its pe...

  3. An introduction to superprocesses

    CERN Document Server

    Etheridge, Alison M

    2000-01-01

    Over the past 20 years, the study of superprocesses has expanded into a major industry and can now be regarded as a central theme in modern probability theory. This book is intended as a rapid introduction to the subject, geared toward graduate students and researchers in stochastic analysis. A variety of different approaches to the superprocesses emerged over the last ten years. Yet no one approach superseded any others. In this book, readers are exposed to a number of different ways of thinking about the processes, and each is used to motivate some key results. The emphasis is on why results are true rather than on rigorous proof. Specific results are given, including extensive references to current literature for their general form.

  4. Superconductivity an introduction

    CERN Document Server

    Kleiner, Reinhold

    2016-01-01

    The third edition of this proven text has been developed further in both scope and scale to reflect the potential for superconductivity in power engineering to increase efficiency in electricity transmission or engines. The landmark reference remains a comprehensive introduction to the field, covering every aspect from fundamentals to applications, and presenting the latest developments in organic superconductors, superconducting interfaces, quantum coherence, and applications in medicine and industry. Due to its precise language and numerous explanatory illustrations, it is suitable as an introductory textbook, with the level rising smoothly from chapter to chapter, such that readers can build on their newly acquired knowledge. The authors cover basic properties of superconductors and discuss stability and different material groups with reference to the latest and most promising applications, devoting the last third of the book to applications in power engineering, medicine, and low temperature physics. An e...

  5. Semiconductor physics an introduction

    CERN Document Server

    Seeger, Karlheinz

    1999-01-01

    Semiconductor Physics - An Introduction - is suitable for the senior undergraduate or new graduate student majoring in electrical engineering or physics. It will also be useful to solid-state scientists and device engineers involved in semiconductor design and technology. The text provides a lucid account of charge transport, energy transport and optical processes, and a detailed description of many devices. It includes sections on superlattices and quantum well structures, the effects of deep-level impurities on transport, the quantum Hall effect and the calculation of the influence of a magnetic field on the carrier distribution function. This 6th edition has been revised and corrected, and new sections have been added to different chapters.

  6. Introduction to thermoelectricity

    CERN Document Server

    Goldsmid, H Julian

    2016-01-01

    This book is a comprehensive introduction to all aspects of thermoelectric energy conversion. It covers both theory and practice. The book is timely as it refers to the many improvements that have come about in the last few years through the use of nanostructures. The concept of semiconductor thermoelements led to major advances during the second half of the twentieth century, making Peltier refrigeration a widely used technique. The latest materials herald thermoelectric generation as the preferred technique for exploiting low-grade heat. The book shows how progress has been made by increasing the thermal resistivity of the lattice until it is almost as large as it is for glass. It points the way towards the attainment of similar improvements in the electronic parameters. It does not neglect practical considerations, such as the desirability of making thermocouples from inexpensive and environmentally acceptable materials. The second edition was extended to also include recent advances in thermoelectric ener...

  7. Introduction to biosensors.

    Science.gov (United States)

    Bhalla, Nikhil; Jolly, Pawan; Formisano, Nello; Estrela, Pedro

    2016-06-30

    Biosensors are nowadays ubiquitous in biomedical diagnosis as well as a wide range of other areas such as point-of-care monitoring of treatment and disease progression, environmental monitoring, food control, drug discovery, forensics and biomedical research. A wide range of techniques can be used for the development of biosensors. Their coupling with high-affinity biomolecules allows the sensitive and selective detection of a range of analytes. We give a general introduction to biosensors and biosensing technologies, including a brief historical overview, introducing key developments in the field and illustrating the breadth of biomolecular sensing strategies and the expansion of nanotechnological approaches that are now available. © 2016 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  8. Introduction to morphogenetic computing

    CERN Document Server

    Resconi, Germano; Xu, Guanglin

    2017-01-01

    This book offers a concise introduction to morphogenetic computing, showing that its use makes global and local relations, defects in crystal non-Euclidean geometry databases with source and sink, genetic algorithms, and neural networks more stable and efficient. It also presents applications to database, language, nanotechnology with defects, biological genetic structure, electrical circuit, and big data structure. In Turing machines, input and output states form a system – when the system is in one state, the input is transformed into output. This computation is always deterministic and without any possible contradiction or defects. In natural computation there are defects and contradictions that have to be solved to give a coherent and effective computation. The new computation generates the morphology of the system that assumes different forms in time. Genetic process is the prototype of the morphogenetic computing. At the Boolean logic truth value, we substitute a set of truth (active sets) values with...

  9. Introduction to bosonization

    International Nuclear Information System (INIS)

    Miranda, E.

    2003-01-01

    This is a pedagogical introduction to the general technique of bosonization of one-dimensional systems starting from scratch and assuming very little besides basic quantum mechanics and second quantization. The formalism is developed in a self-contained fashion and applied to the spinless and spin-1/2 Luttinger models, working out both single and two particle correlation functions. The implications of these results for the specific cases of the (anisotropic) Heisenberg and the Hubbard models are discussed. Although everything in these notes can be found in the published literature, detailed and explicit calculations of most of the results are given, which may prove useful to beginning graduate students or researchers in this area. (author)

  10. Introduction to complex plasmas

    International Nuclear Information System (INIS)

    Bonitz, Michael; Ludwig, Patrick; Horing, Norman

    2010-01-01

    Complex plasmas differ from traditional plasmas in many ways: these are low-temperature high pressure systems containing nanometer to micrometer size particles which may be highly charged and strongly interacting. The particles may be chemically reacting or be in contact with solid surfaces, and the electrons may show quantum behaviour. These interesting properties have led to many applications of complex plasmas in technology, medicine and science. Yet complex plasmas are extremely complicated, both experimentally and theoretically, and require a variety of new approaches which go beyond standard plasma physics courses. This book fills this gap presenting an introduction to theory, experiment and computer simulation in this field. Based on tutorial lectures at a very successful recent Summer Institute, the presentation is ideally suited for graduate students, plasma physicists and experienced undergraduates. (orig.)

  11. Introduction to Complex Plasmas

    CERN Document Server

    Bonitz, Michael; Ludwig, Patrick

    2010-01-01

    Complex plasmas differ from traditional plasmas in many ways: these are low-temperature high pressure systems containing nanometer to micrometer size particles which may be highly charged and strongly interacting. The particles may be chemically reacting or be in contact with solid surfaces, and the electrons may show quantum behaviour. These interesting properties have led to many applications of complex plasmas in technology, medicine and science. Yet complex plasmas are extremely complicated, both experimentally and theoretically, and require a variety of new approaches which go beyond standard plasma physics courses. This book fills this gap presenting an introduction to theory, experiment and computer simulation in this field. Based on tutorial lectures at a very successful recent Summer Institute, the presentation is ideally suited for graduate students, plasma physicists and experienced undergraduates.

  12. Introduction to biomedical engineering

    CERN Document Server

    Enderle, John D; Blanchard, Susan M

    2005-01-01

    Under the direction of John Enderle, Susan Blanchard and Joe Bronzino, leaders in the field have contributed chapters on the most relevant subjects for biomedical engineering students. These chapters coincide with courses offered in all biomedical engineering programs so that it can be used at different levels for a variety of courses of this evolving field. Introduction to Biomedical Engineering, Second Edition provides a historical perspective of the major developments in the biomedical field. Also contained within are the fundamental principles underlying biomedical engineering design, analysis, and modeling procedures. The numerous examples, drill problems and exercises are used to reinforce concepts and develop problem-solving skills making this book an invaluable tool for all biomedical students and engineers. New to this edition: Computational Biology, Medical Imaging, Genomics and Bioinformatics. * 60% update from first edition to reflect the developing field of biomedical engineering * New chapters o...

  13. I-Introduction

    International Nuclear Information System (INIS)

    1998-01-01

    In this report, each sector starts with an introduction presenting the state of each sector in Lebanon, followed by the methodology adopted in order to compute emissions of greenhouse gases by sources and removals by sinks, in accordance with IPCC guidelines, complemented by experts' assumptions in estimating greenhouse gases and finally accompanied by the IPCC sectoral tables which present the result obtained in each sector. The report ends with an 'Appendices' chapter which includes all worksheets, showing the computations made resulting in emitted or removed greenhouse gas quantities. This executive summary described in the IPCC summary presents the main results obtained in each sector. In the last paragraph, the global warming potential of the greenhouse gases emitted in Lebanon in 1994 is provided for three calculated time horizons, based on the '1995 IPCC technical summary of working group I' report. (au)

  14. Introduction to Waste Management

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund

    2011-01-01

    Solid waste management is as old as human civilization, although only considered an engineering discipline for about one century. The change from the previous focus on public cleansing of the cities to modern waste management was primarily driven by industrialization, which introduced new materials...... and chemicals, dramatically changing the types and composition of waste, and by urbanization making waste management in urban areas a complicated and costly logistic operation. This book focuses on waste that commonly appears in the municipal waste management system. This chapter gives an introduction to modern...... waste management, including issues as waste definition, problems associated with waste, waste management criteria and approaches to waste management. Later chapters introduce aspects of engineering (Chapter 1.2), economics (Chapter 1.3) and regulation (Chapter 1.4)....

  15. Photonics an introduction

    CERN Document Server

    Reider, Georg A

    2016-01-01

    This book provides a comprehensive introduction into photonics, from the electrodynamic and quantum mechanic fundamentals to the level of photonic components and building blocks such as lasers, amplifiers, modulators, waveguides, and detectors. The book will serve both as textbook and as a reference work for the advanced student or scientist. Theoretical results are derived from basic principles with convenient, yet state-of-the-art mathematical tools, providing not only deeper understanding but also familiarization with formalisms used in the relevant technical literature and research articles. Among the subject matters treated are polarization optics, pulse and beam propagation, waveguides, light–matter interaction, stationary and transient behavior of lasers, semiconductor optics and lasers (including low-dimensional systems such as quantum wells), detector technology, photometry, and colorimetry. Nonlinear optics are elaborated comprehensively. The book is intended for both students of physics and elect...

  16. Introduction to transonic aerodynamics

    CERN Document Server

    Vos, Roelof

    2015-01-01

    Written to teach students the nature of transonic flow and its mathematical foundation, this book offers a much-needed introduction to transonic aerodynamics. The authors present a quantitative and qualitative assessment of subsonic, supersonic, and transonic flow around bodies in two and three dimensions. The book reviews the governing equations and explores their applications and limitations as employed in modeling and computational fluid dynamics.  Some concepts, such as shock and expansion theory, are examined from a numerical perspective. Others, including shock-boundary-layer interaction, are discussed from a qualitative point of view. The book includes 60 examples and more than 200 practice problems. The authors also offer analytical methods such as Method of Characteristics (MOC) that allow readers to practice with the subject matter.  The result is a wealth of insight into transonic flow phenomena and their impact on aircraft design, including compressibility effects, shock and expansion waves, sho...

  17. Introduction to representation theory

    CERN Document Server

    Etingof, Pavel; Hensel, Sebastian; Liu, Tiankai; Schwendner, Alex

    2011-01-01

    Very roughly speaking, representation theory studies symmetry in linear spaces. It is a beautiful mathematical subject which has many applications, ranging from number theory and combinatorics to geometry, probability theory, quantum mechanics, and quantum field theory. The goal of this book is to give a "holistic" introduction to representation theory, presenting it as a unified subject which studies representations of associative algebras and treating the representation theories of groups, Lie algebras, and quivers as special cases. Using this approach, the book covers a number of standard topics in the representation theories of these structures. Theoretical material in the book is supplemented by many problems and exercises which touch upon a lot of additional topics; the more difficult exercises are provided with hints. The book is designed as a textbook for advanced undergraduate and beginning graduate students. It should be accessible to students with a strong background in linear algebra and a basic k...

  18. Introduction to cosmology

    CERN Document Server

    Ryden, Barbara

    2017-01-01

    This second edition of Introduction to Cosmology is an exciting update of an award-winning textbook. It is aimed primarily at advanced undergraduate students in physics and astronomy, but is also useful as a supplementary text at higher levels. It explains modern cosmological concepts, such as dark energy, in the context of the Big Bang theory. Its clear, lucid writing style, with a wealth of useful everyday analogies, makes it exceptionally engaging. Emphasis is placed on the links between theoretical concepts of cosmology and the observable properties of the universe, building deeper physical insights in the reader. The second edition includes recent observational results, fuller descriptions of special and general relativity, expanded discussions of dark energy, and a new chapter on baryonic matter that makes up stars and galaxies. It is an ideal textbook for the era of precision cosmology in the accelerating universe.

  19. Introduction to supergravity

    CERN Document Server

    Tanii, Yoshiaki

    2014-01-01

    This book is a pedagogical introduction to supergravity, a gravitational field theory that includes supersymmetry (symmetry between bosons and fermions) and is a generalization of Einstein's general relativity. Supergravity provides a low-energy effective theory of superstring theory, which has attracted much attention as a candidate for the unified theory of fundamental particles, and it is a useful tool for studying non-perturbative properties of superstring theory such as D-branes and string duality. This work considers classical supergravities in four and higher spacetime dimensions with their applications to superstring theory in mind. More concretely, it discusses classical Lagrangians (or field equations) and symmetry properties of supergravities. Besides local symmetries, supergravities often have global non-compact symmetries, which play a crucial role in their applications to superstring theory. One of the main features of this book is its detailed discussion of these non-compact symmetries. The aim...

  20. Superconductivity an introduction

    CERN Document Server

    Mangin, Philippe

    2017-01-01

    This book proposes a thorough introduction for a varied audience. The reader will master London theory and the Pippard equations, and go on to understand type I and type II superconductors (their thermodynamics, magnetic properties, vortex dynamics, current transport…), Cooper pairs and the results of BCS theory. By studying coherence and flux quantization he or she will be lead to the Josephson effect which, with the SQUID, is a good example of the applications. The reader can make up for any gaps in his knowledge with the use of the appendices, follow the logic behind each model, and assimilate completely the underlying concepts. Approximately 250 illustrations help in developing a thorough understanding. This volume is aimed towards masters and doctoral students, as well as advanced undergraduates, teachers and researchers at all levels coming from a broad range of subjects (chemistry, physics, mechanical and electrical engineering, materials science…). Engineers working in industry will have a useful ...