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Sample records for ac plasma polymerisation

  1. Surface modification of PET films using pulsed AC plasma polymerisation aimed at preventing protein adsorption

    DEFF Research Database (Denmark)

    Ademovic, Z.; Wei, J.; Winther-Jensen, Bjørn

    2005-01-01

    We utilise pulsed AC plasma polymerisation to create thin films that either contain reactive acid functional groups (by deposition of maleic anhydride (MAH) followed by hydrolysis) or are poly(ethylene glycol) (PEG)-like in nature (by using diethylene glycol vinyl ether (DEGVE) as monomer). The MAH...... films were further modified with PEG chains using a two-step wet chemical method. For the DEGVE films the plasma power was varied in order to change the degree of monomer fragmentation and thus retention of PEG-like character. The chemistry of the surfaces was determined using Fourier-transform infrared...

  2. On the iodine doping process of plasma polymerised thiophene layers

    NARCIS (Netherlands)

    Groenewoud, L.M.H.; Engbers, G.H.M.; White, R.; Feijen, Jan

    2002-01-01

    To make a fair comparison of the conductive properties of plasma polymerised thiophene (PPT) layers deposited under different conditions, optimal doping procedures should be applied. The iodine doping process of PPT layers deposited at high (HP) and low (LP) pressure has been studied in detail.

  3. On the iodine doping process of plasma polymerised thiophene layers

    NARCIS (Netherlands)

    Groenewoud, L.M.H.; Engbers, G.H.M.; White, R.; Feijen, J.

    2001-01-01

    To make a fair comparison of the conductive properties of plasma polymerised thiophene (PPT) layers deposited under different conditions, optimal doping procedures should be applied. The iodine doping process of PPT layers deposited at high (HP) and low (LP) pressure has been studied in detail. Dopi

  4. Hydrolysis and stability of thin pulsed plasma polymerised maleic anhydride coatings

    DEFF Research Database (Denmark)

    Drews, Joanna Maria; Launay, Héléne; Hansen, Charles M.

    2008-01-01

    were obtained at constant plasma power by adjusting the polymerisation time. The results show that the hydrolysis resistance of the modified layer is determined by the power used in the plasma polymerisation, while changes in the chemistry of the modified layer are insignificant....

  5. Effect of dopants on the transparency and stability of the conductivity of plasma polymerised thiophene layers

    NARCIS (Netherlands)

    Groenewoud, L.M.H.; Weinbeck, A.E.; Engbers, G.H.M.; Feijen, J.

    2002-01-01

    Iodine is frequently used as dopant for plasma polymerised thiophene (PPT) layers, but suffers from several drawbacks such as the rapidly decaying conductivity upon exposure to air, and the absorption of light by iodine species that are present in the doped PPT layer (i.e., I2, I3− , and I5−). This

  6. Osteoblasts with impaired spreading capacity benefit from the positive charges of plasma polymerised allylamine

    Directory of Open Access Journals (Sweden)

    F Kunz

    2015-03-01

    Full Text Available Bone diseases such as osteoporosis, osteoarthritis and rheumatoid arthritis, impinge on the performance of orthopaedic implants by impairing bone regeneration. For this reason, the development of effective surface modifications supporting the ingrowth of implants in morbid bone tissue is essential. Our study is designed to elucidate if cells with restricted cell-function limiting adhesion processes benefit from plasma polymer deposition on titanium. We used the actin filament disrupting agent cytochalasin D (CD as an experimental model for cells with impaired actin cytoskeleton. Indeed, the cell’s capacity to adhere and spread was drastically reduced due to shortened actin filaments and vinculin contacts that were smaller. The coating of titanium with a positively charged nanolayer of plasma polymerised allylamine (PPAAm abrogated these disadvantages in cell adhesion and the CD-treated osteoblasts were able to spread significantly. Interestingly, PPAAm increased spreading by causing enhanced vinculin number and contact length, but without significantly reorganising actin filaments. PPAAm with the monomer allylamine was deposited in a microwave-excited low-pressure plasma-processing reactor. Cell physiology was monitored by flow cytometry and confocal laser scanning microscopy, and the length and number of actin filaments was quantified by mathematical image processing. We showed that biomaterial surface modification with PPAAm could be beneficial even for osteoblasts with impaired cytoskeleton components. These insights into in vitro conditions may be used for the evaluation of future strategies to design implants for morbid bone tissue.

  7. Surface functionalisation of polypropylene hernia-repair meshes by RF-activated plasma polymerisation of acrylic acid and silver nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Nisticò, Roberto, E-mail: roberto.nistico@unito.it [University of Torino, Department of Chemistry and NIS Research Centre, Via P. Giuria 7, 10125 Torino (Italy); Rosellini, Andrea [University of Torino, Department of Chemistry and NIS Research Centre, Via P. Giuria 7, 10125 Torino (Italy); Rivolo, Paola [Politecnico di Torino, Dipartimento di Scienza Applicata e Tecnologia, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Faga, Maria Giulia [CNR-IMAMOTER, Strada delle Cacce 73, 10135 Torino (Italy); Lamberti, Roberta; Martorana, Selanna [Herniamesh S.r.l., Via F.lli Meliga 1/C, 10034 Chivasso (Italy); Castellino, Micaela [Center for Space Human Robotics, Istituto Italiano di Tecnologia, Corso Trento 21, 10129 Torino (Italy); Virga, Alessandro; Mandracci, Pietro [Politecnico di Torino, Dipartimento di Scienza Applicata e Tecnologia, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Malandrino, Mery; Magnacca, Giuliana [University of Torino, Department of Chemistry and NIS Research Centre, Via P. Giuria 7, 10125 Torino (Italy)

    2015-02-15

    Graphical abstract: - Highlights: • Polypropylene meshes for hernioplasty were surface functionalised via plasma-polymerisation to confer adhesive properties. • Subsequently, silver nanoparticles were loaded to add antibacterial activity. • Materials were physico-chemical characterised and adhesive properties evaluated. - Abstract: Hernia diseases are among the most common and diffuse causes of surgical interventions. Unfortunately, still nowadays there are different phenomena which can cause the hernioplasty failure, for instance post-operative prostheses displacements and proliferation of bacteria in the surgical site. In order to limit these problems, commercial polypropylene (PP) and polypropylene/Teflon (PP/PTFE) bi-material meshes were surface functionalised to confer adhesive properties (and therefore reduce undesired displacements) using polyacrylic acid synthesized by plasma polymerisation (PPAA). A broad physico-chemical and morphological characterisation was carried out and adhesion properties were investigated by means of atomic force microscopy (AFM) used in force/distance (F/D) mode. Once biomedical devices surface was functionalised by PPAA coating, metallic silver nanoparticles (AgNPs) with antimicrobial properties were synthesised and loaded onto the polymeric prostheses. The effect of the PPAA, containing carboxylic functionalities, adhesive coating towards AgNPs loading capacity was verified by means of X-ray photoelectron spectroscopy (XPS). Preliminary measurement of the Ag loaded amount and release in water were also investigated via inductively coupled plasma atomic emission spectroscopy (ICP-AES). Promising results were obtained for the functionalised biomaterials, encouraging future in vitro and in vivo tests.

  8. Memory effect in ac plasma displays

    Science.gov (United States)

    Szlenk, K.; Obuchowicz, E.

    1993-10-01

    The bistable or `memory' mode of operation of an ac plasma display panel is presented. The difference between dc and ac plasma panel operation from the point of view of memory function is discussed. The graphic ac plasma display with thin film Cr-Cu-Cr electrodes was developed in OBREP and its basic parameters are described. It consists of 36 X 59 picture elements, its outer dimensions are: 76 X 52 mm2 and the screen size is: 49 X 30 mm2. The different dielectric glass materials were applied as dielectric layers and the influence of the properties of these materials on display parameters and memory function was investigated.

  9. Controlling Interface Adhesion and Fracture Properties in Composite Materials by Plasma Polymerisation

    DEFF Research Database (Denmark)

    Goutianos, S.; Drews, J.; Fæster Nielsen, Søren

    2006-01-01

    The effect of plasma polymerization on the interface adhesion between carbon fibres and an epoxy matrix was investigated. This was done by loading with pure bending moments in nominal mode I planar glassy carbon/ epoxy specimens. The glassy carbon was used to simulate the carbon fibres. The exper...

  10. Controlling Interface Adhesion and Fracture Properties in Composite Materials by Plasma Polymerisation

    DEFF Research Database (Denmark)

    Goutianos, S.; Drews, J.; Fæster Nielsen, Søren

    2006-01-01

    The effect of plasma polymerization on the interface adhesion between carbon fibres and an epoxy matrix was investigated. This was done by loading with pure bending moments in nominal mode I planar glassy carbon/ epoxy specimens. The glassy carbon was used to simulate the carbon fibres. The exper...

  11. AC plasma anemometer—characteristics and design

    Science.gov (United States)

    Marshall, Curtis; Matlis, Eric; Corke, Thomas; Gogineni, Sivaram

    2015-08-01

    The characteristics and design of a high-bandwidth flow sensor that uses an AC glow discharge (plasma) as the sensing element is presented. The plasma forms in the air gap between two protruding low profile electrodes attached to a probe body. The output from the anemometer is an amplitude modulated version of the AC voltage input that contains information about the mean and fluctuating velocity components. The anemometer circuitry includes resistance and capacitance elements that simulate a dielectric-barrier to maintain a diffuse plasma, and a constant-current feedback control that maintains operation within the desired glow discharge regime over an extended range of air velocities. Mean velocity calibrations are demonstrated over a range from 0 to 140 m s-1. Over this velocity range, the mean output voltage varied linearly with air velocity, providing a constant static sensitivity. The effect of the electrode gap and input AC carrier frequency on the anemometer static sensitivity and dynamic response are investigated. Experiments are performed to compare measurements obtained with a plasma sensor operating at two AC carrier frequencies against that of a constant-temperature hot-wire. All three sensors were calibrated against the same known velocity reference. An uncertainty based on the standard deviation of the velocity calibration fit was applied to the mean and fluctuating velocity measurements of the three sensors. The motivation is not to replace hot-wires as a general measurement tool, but rather as an alternative to hot-wires in harsh environments or at high Mach numbers where they either have difficulty in surviving or lack the necessary frequency response.

  12. Surface Polymerisation Methods for Optimised Adhesion

    DEFF Research Database (Denmark)

    Drews, Joanna Maria

    Arbejdet har fokuseret på muligheder for at forstærke kompositmaterialer til højteknologiske anvendelser fx til vindmøllevinger. Forskningen har derfor været centreret om plasma polymerisation af henholdsvis maleic anhydrid (MAH) og 1,2-methylenedioxybenzen til tynde film på modelkulstofsubstrate...

  13. Ion irradiation as a tool for modifying the surface and optical properties of plasma polymerised thin films

    Science.gov (United States)

    Grant, Daniel S.; Bazaka, Kateryna; Siegele, Rainer; Holt, Stephen A.; Jacob, Mohan V.

    2015-10-01

    Radio frequency (R.F.) glow discharge polyterpenol thin films were prepared on silicon wafers and irradiated with I10+ ions to fluences of 1 × 1010 and 1 × 1012 ions/cm2. Post-irradiation characterisation of these films indicated the development of well-defined nano-scale ion entry tracks, highlighting prospective applications for ion irradiated polyterpenol thin films in a variety of membrane and nanotube-fabrication functions. Optical characterisation showed the films to be optically transparent within the visible spectrum and revealed an ability to selectively control the thin film refractive index as a function of fluence. This indicates that ion irradiation processing may be employed to produce plasma-polymer waveguides to accommodate a variety of wavelengths. XRR probing of the substrate-thin film interface revealed interfacial roughness values comparable to those obtained for the uncoated substrate's surface (i.e., both on the order of 5 Å), indicating minimal substrate etching during the plasma deposition process.

  14. Calculated characteristics of an ac plasma display panel cell

    Energy Technology Data Exchange (ETDEWEB)

    Boeuf, J.P.; Pitchford, L.C. [Universite Paul Sabatier, Toulouse (France)

    1996-02-01

    Equipotential contours and contours of constant power deposition into excitation of xenon, calculated from a two-dimensional (2-D) fluid model, are presented at times during the evolution of a single discharge event in an ac plasma display panel cell with a dielectric barrier rib geometry.

  15. Water treatment by the AC gliding arc air plasma

    Science.gov (United States)

    Gharagozalian, Mehrnaz; Dorranian, Davoud; Ghoranneviss, Mahmood

    2017-06-01

    In this study, the effects of gliding arc (G Arc) plasma system on the treatment of water have been investigated experimentally. An AC power supply of 15 kV potential difference at 50 Hz frequency was employed to generate plasma. Plasma density and temperature were measured using spectroscopic method. The water was contaminated with staphylococcus aureus (Gram-positive) and salmonella bacteria (Gram-negative), and Penicillium (mold fungus) individually. pH, hydrogen peroxide, and nitride contents of treated water were measured after plasma treatment. Decontamination of treated water was determined using colony counting method. Results indicate that G Arc plasma is a powerful and green tool to decontaminate water without producing any byproducts.

  16. Research on the Plasma Anemometer Based on AC Glow Discharge

    Directory of Open Access Journals (Sweden)

    Bing Yu

    2017-01-01

    Full Text Available A new plasma anemometer based on AC glow discharge is designed in this article. Firstly, theoretical analysis of plasma anemometer working principle is introduced to prove the feasibility of the experimental measurement method. Then the experiments are carried out to study the effects of different parameters on the static discharge characteristics of the plasma anemometer system, by which the system optimization methods are obtained. Finally, several groups of appropriate parameters are selected to build the plasma anemometer system based on resistance capacitance coupling negative feedback AC glow discharge, and different airflow speeds are applied to obtain the achievable velocity measurement range. The results show that there is a linear relationship between airflow velocity and discharge current in an allowable error range, which can be applied for airflow velocity measurement. Negative feedback coupling module, which is composed of the coupling resistance and the coupling capacitance, has good effects on improving the system stability. The measurement range of the airflow velocity is significantly increased when the electrode gap is 3 mm, coupling resistance is 470 Ω, and coupling capacitance is 220 pF.

  17. Analysis of Physics Processes in the AC Plasma Torch Discharge under High Pressure

    Science.gov (United States)

    Safronov, A. A.; Vasilieva, O. B.; Dudnik, J. D.; E Kuznetsov, V.; Kuchina, J. A.; Shiryaev, V. N.; Pavlov, A. V.

    2017-04-01

    The paper is devoted to investigation of electrophysical processes in the electric discharge generated by a three-phase AC plasma torch when using a high pressure inert working gas. AC plasma torch design with end electrodes intended for work on inert gases at pressures up to 81 bar is studied. Current-voltage characteristics for different gas flow rates and pressures are presented. Physical processes characteristics of the arising voltage ripples which depend on various working parameters of the plasma torch have been investigated. Arc burning processes in the electric discharge chamber of the three-phase AC plasma torch at various working parameters were photographed.

  18. Investigation of the AC Plasma Torch Working Conditions for the Plasma Chemical Applications

    Science.gov (United States)

    Safronov, A. A.; Vasilieva, O. B.; Dudnik, J. D.; E Kuznetsov, V.; Shiryaev, V. N.; Subbotin, D. I.; Pavlov, A. V.

    2017-04-01

    The presented design and parameters of a three-phase AC plasma torch with the power up to 500 kW, flow rate of air 30-50 g/s (temperature up to 5000 K) could be used in different plasma chemical processes. Range of measured plasma temperature is 3500-5000 K. The paper presents investigations of the plasma torch operation modes for its application in plasma chemical technologies. Plasma chemical technologies for various purposes (processing, destruction of various wastes, including technological and hazardous waste, conversion or production of chemicals to obtain nanoscale materials, etc.) are very promising in terms of the process efficiency. Their industrial use is difficult due to the lack of inexpensive and reliable plasma torches providing the desired level of temperature, enthalpy of the working gas and other necessary conditions for the process. This problem can be solved using a considered design of a three-phase alternating current plasma torch with power of 150-500 kW with working gas flow rate of 30-50 g/s with mass average temperature up to 5000K on the basis of which an industrial plasma chemical plant can be created. The basis of the plasma torch operation is a railgun effect that is the principle of arc movement in the field of its own current field. Thanks to single supply of power to the arc, arcs forming in the discharge chamber of the plasma torch move along the electrodes under the action of electrodynamic forces resulting from the interaction of the arc current with its own magnetic field. Under the condition of the three-phase supply voltage, arc transits from the electrode to the electrode with change in the anodic and cathodic phases with frequency of 300 Hz. A special feature of this design is the ability to organize the movement of the arc attachment along the electrode, thus ensuring an even distribution of the thermal load and thus achieve long time of continuous operation of the plasma torch. The parameters of the plasma jet of the

  19. The Feasibility of Applying AC Driven Low-Temperature Plasma for Multi-Cycle Detonation Initiation

    Science.gov (United States)

    Zheng, Dianfeng

    2016-11-01

    Ignition is a key system in pulse detonation engines (PDE). As advanced ignition methods, nanosecond pulse discharge low-temperature plasma ignition is used in some combustion systems, and continuous alternating current (AC) driven low-temperature plasma using dielectric barrier discharge (DBD) is used for the combustion assistant. However, continuous AC driven plasmas cannot be used for ignition in pulse detonation engines. In this paper, experimental and numerical studies of pneumatic valve PDE using an AC driven low-temperature plasma igniter were described. The pneumatic valve was jointly designed with the low-temperature plasma igniter, and the numerical simulation of the cold-state flow field in the pneumatic valve showed that a complex flow in the discharge area, along with low speed, was beneficial for successful ignition. In the experiments ethylene was used as the fuel and air as oxidizing agent, ignition by an AC driven low-temperature plasma achieved multi-cycle intermittent detonation combustion on a PDE, the working frequency of the PDE reached 15 Hz and the peak pressure of the detonation wave was approximately 2.0 MPa. The experimental verifications of the feasibility in PDE ignition expanded the application field of AC driven low-temperature plasma. supported by National Natural Science Foundation of China (No. 51176001)

  20. Polymerisation of composite materials in space environment for development of moon base

    Science.gov (United States)

    Kondyurina, I.; Kondyurin, A.; Lauke, B.

    The best way for a Moon base creation is a deployment of light construction on Moon surface after landing. The construction has to be light in deployment and hard at exploitation. A number of proposals for solidification of deployed constructions in space were presented, but the best way is a chemical reaction which leads to a formation of hard frame of space construction. A technology of large-size moon module for industrial and scientific applications is developed on the base of polymerisation technique of composite material with liquid polymer matrix. Experiments with chemical reactions of polymerisation in composite materials under high vacuum, ion beam and plasma discharge showed a possibility to use a liquid viscous polymer matrix of composite materials under space conditions without hermetic coating. Epoxy resins with thermal and photo initiation system of polymerisation were studied. The effects of initiation of the polymerisation reaction under simulated space factors were observed. The polymerised frames can be used in energetic, electronic and other industries on Moon surface. The investigations were partially supported by Alexander von Humboldt Foundation and European Space Agency, ESTEC (contract 17083/03/NL/Sfe "Space Environmental Effects on the Polymerisation of Composite Structures"). 1. A.Kondyurin, B.Lauke, Polymerisation processes in simulated free space conditions, Proceedings of the 9th International Symposium on Materials in a Space Environment, Noordwijk, The Netherlands, 16-20 June, 2003, ESA SP-540, September 2003, pp.75-80. 2. V.A.Briskman, T.M.Yudina, K.G.Kostarev, A.V.Kondyurin, V.B.Leontyev, M.G.Levkovich, A.L.Mashinsky, G.S.Nechitailo, Polymerization in microgravity as a new process in space technology, Acta Astronautica, vol.48, N2-3, 2001, pp.169-180.

  1. Polymerisation processes in expoy resins under influence of free space environment

    Science.gov (United States)

    Kondyurin, A.; Lauke, B.; Kondyurina, I.

    A creation of large size constructions in space or on celestial bodies is possible by the way of chemical reactions of liquid viscous components under space environment conditions [1-2]. In particular, a new technology for large-size space module for electronic components, energy and materials production is developed on the basis of polymerisation technique. The factors of free space environment have a significant influence on the polymerisation processes. The polymerisation processes in active liquid components are sensitive to microgravitation, temperature variations (-150{ldots}+1500C), high vacuum (10-3{ldots}10-7 Pa), atomic oxygen flux (on LEO), UV and VUV irradiations, X-ray and γ -irradiations, high energy electron and ion fluxes. Experiments of polymerisation processes under simulated free space conditions were conducted. The influences of high vacuum, high energy ion beam and rf- and mw-plasma on polymerisation of epoxy resins were observed. The effects of low molecular components evaporations, free radical formations, additional chemical reactions and mixing processes during polymerisation were observed. Our results showed, that the space factors can initiate the polymerisation reaction in epoxy matrix of glass and carbon fibre composites. The result can be used for a technology for large size constructions on Earth orbit, in far space and on space bodies as for deployed antennas, solar sail stringers, solar shield stringers, frame for large-size space station, frame for Moon, Mars, asteroids bases, frame for space plant on Earth orbit and on other celestial bodies. The study was partially supported by Alexander von Humboldt Foundation (A. Kondyurin) and European Space Agency, ESTEC (contract 17083/03/NL/Sfe "Space Environmental Effects on the Polymerisation of Composite Structures"). 1. A.Kondyurin, B.Lauke, Polymerisation processes in simulated free space conditions, Proceedings of the 9th International Symposium on Materials in a Space Environment

  2. Atomic oxygen behavior at downstream of AC excited atmospheric pressure He plasma jet

    Science.gov (United States)

    Takeda, Keigo; Ishikawa, Kenji; Tanaka, Hiromasa; Sekine, Makoto; Hori, Masaru

    2016-09-01

    Applications of atmospheric pressure plasma jets (APPJ) have been investigated in the plasma medical fields such as cancer therapy, blood coagulation, etc. Reactive species generated by the plasma jet interacts with the biological surface. Therefore, the issue attracts much attentions to investigate the plasma effects on targets. In our group, a spot-size AC excited He APPJ have been used for the plasma medicine. From diagnostics of the APPJ using optical emission spectroscopy, the gas temperature and the electron density was estimated to be 299 K and 3.4 ×1015 cm-3. The AC excited He APPJ which affords high density plasma at room temperature is considered to be a powerful tool for the medical applications. In this study, by using vacuum ultraviolet absorption spectroscopy, the density of atomic oxygen on a floating copper as a target irradiated by the He APPJ was measured as a function of the distance between the plasma source and the copper wire. The measured density became a maximum value around 8 ×1013 cm-3 at 12 mm distance, and then decreased over the distance. It is considered that the behavior was due to the changes in the plasma density on the copper wire and influence of ambient air.

  3. Parametric studies of AC plasma display panel cells in complex geometries

    Energy Technology Data Exchange (ETDEWEB)

    Punset, C.; Boeuf, J.P.; Pitchford, L.C. [Univ. Paul Sabatier, Toulouse (France). CPAT

    1996-12-31

    The authors have developed a two-dimensional fluid model of AC plasma panel cells. This model was used to study the operation of a plasma panel cell in a barrier rib geometry in single pulse operation. In this communication, they report results from calculations in several different geometries and for a series of applied voltage pulses. The purpose of this work is to study the effect of geometry on the electrical characteristics of AC plasma display panel cells. The calculations reported here are representative of actual device operation. They have also used the model to study the effect of the geometrical parameters of the cell, to optimize the discharge efficiency in producing UV photons and to study cross-talk, i.e., interaction between adjacent cells. The conclusions of these parametric studies will be presented.

  4. Polymerisation of composite materials in space environment for development of a Moon base

    Science.gov (United States)

    Kondyurina, I.; Kondyurin, A.; Lauke, B.; Figiel, Ł.; Vogel, R.; Reuter, U.

    Deployment of light construction on the Moon surface after landing is a real way to create a Moon base. The construction has to be soft at deployment and hard at exploitation. A number of methods for solidification of deployed constructions in space was proposed, but the best way is a chemical reaction which leads to formation of the hard frame of space construction. The technology of large-size Moon module for industrial and scientific applications is developed by the way of the polymerisation process in composite material with liquid polymer matrix. Experiments with chemical reactions of polymerisation in composite materials under high vacuum, ion beam and plasma discharge have shown a possibility to use the liquid polymer matrix of composite materials under space conditions without hermetic coating. Epoxy resins with thermal initiation system of polymerisation were studied. The effects of initiation of the polymerisation reaction under simulated space factors were observed. Structure and mechanical properties of cured composite under simulated space conditions were analysed and compared with composite cured by usual ground technology. The proposed frame technology can be used for energetic, electronic and other industry building on the Moon.

  5. Characterising the association of latency with α1-antitrypsin polymerisation using a novel monoclonal antibody

    Science.gov (United States)

    Tan, Lu; Perez, Juan; Mela, Marianna; Miranda, Elena; Burling, Keith A; Rouhani, Farshid N; DeMeo, Dawn L; Haq, Imran; Irving, James A; Ordóñez, Adriana; Dickens, Jennifer A; Brantly, Mark; Marciniak, Stefan J; Alexander, Graeme J M; Gooptu, Bibek; Lomas, David A

    2015-01-01

    α1-Antitrypsin is primarily synthesised in the liver, circulates to the lung and protects pulmonary tissues from proteolytic damage. The Z mutant (Glu342Lys) undergoes inactivating conformational change and polymerises. Polymers are retained within the hepatocyte endoplasmic reticulum (ER) in homozygous (PiZZ) individuals, predisposing the individuals to hepatic cirrhosis and emphysema. Latency is an analogous process of inactivating, intra-molecular conformational change and may co-occur with polymerisation. However, the relationship between latency and polymerisation remained unexplored in the absence of a suitable probe. We have developed a novel monoclonal antibody specific for latent α1-antitrypsin and used it in combination with a polymer-specific antibody, to assess the association of both conformers in vitro, in disease and during augmentation therapy. In vitro kinetics analysis showed polymerisation dominated the pathway but latency could be promoted by stabilising monomeric α1-antitrypsin. Polymers were extensively produced in hepatocytes and a cell line expressing Z α1-antitrypsin but the latent protein was not detected despite manipulation of the secretory pathway. However, α1-antitrypsin augmentation therapy contains latent α1-antitrypsin, as did the plasma of 63/274 PiZZ individuals treated with augmentation therapy but 0/264 who were not receiving this medication (p < 10−14). We conclude that latent α1-antitrypsin is a by-product of the polymerisation pathway, that the intracellular folding environment is resistant to formation of the latent conformer but that augmentation therapy introduces latent α1-antitrypsin into the circulation. A suite of monoclonal antibodies and methodologies developed in this study can characterise α1-antitrypsin folding and conformational transitions, and screen methods to improve augmentation therapy. PMID:25462157

  6. Aminopiperidine based complexes for lactide polymerisation.

    Science.gov (United States)

    McKeown, P; Davidson, M G; Lowe, J P; Mahon, M F; Thomas, L H; Woodman, T J; Jones, M D

    2016-03-28

    Herein we report the synthesis and characterisation of a series of salalen and salan ligands derived from 2-(aminomethyl)piperidine. Depending on the choice of starting salicylaldehyde, a bicyclic salan type ligand (1-3H2) or imino salalen type ligand (4-6H, 7-9H2) were prepared. The ligands were successfully complexed to group 4 metals and aluminium; with hafnium and zirconium octahedral complexes, M(1-3)2, were realised; whilst with aluminium tetrahedral and trigonal bipyramidal complexes, Al(1-9)Mex (x = 1,2), were isolated. The complexes have been characterised in solution via(1)H and (13)C{(1)H} NMR spectroscopy and in the solid state by X-ray crystallography. The group 4 complexes were observed to have a fac-fac arrangement of ligands and there were two isomers present when 3H2 was ligated. The imino aluminium complexes Al(7-9)Me were isolated as a mixture of diastereoisomers. The resultant complexes were trialed in the ring opening polymerisation of rac-lactide with both heterotactic and isotactic PLA being demonstrated. Tacticity was found to be dependent on the nature of the ligand and metal used; the M(1-3)2 complexes were generally found to have a heterotactic preference (Pr = 0.67-0.76) and the aluminium polymerisation outcome was dictated more by the steric influence of the ligand, particularly for Al(4/6)Me2/Al(7/9)Me.

  7. New perspectives on the dynamics of AC and DC plasma arcs exposed to cross-fields

    Science.gov (United States)

    Abdo, Youssef; Rohani, Vandad; Cauneau, François; Fulcheri, Laurent

    2017-02-01

    Interactions between an arc and external fields are crucially important for the design and the optimization of modern plasma torches. Multiple studies have been conducted to help better understand the behavior of DC and AC current arcs exposed to external and ‘self-induced’ magnetic fields, but the theoretical foundations remain very poorly explored. An analytical investigation has therefore been carried out in order to study the general behavior of DC and AC arcs under the effect of random cross-fields. A simple differential equation describing the general behavior of a planar DC or AC arc has been obtained. Several dimensionless numbers that depend primarily on arc and field parameters and the main arc characteristics (temperature, electric field strength) have also been determined. Their magnitude indicates the general tendency pattern of the arc evolution. The analytical results for many case studies have been validated using an MHD numerical model. The main purpose of this investigation was deriving a practical analytical model for the electric arc, rendering possible its stabilization and control, and the enhancement of the plasma torch power.

  8. Plasma antennas driven by 5–20 kHz AC power supply

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Jiansen, E-mail: 67093058@qq.com; Chen, Yuli; Sun, Yang; Wu, Huafeng; Liu, Yue; Yuan, Qiumeng [Merchant Marine College, Shanghai Maritime University, Shanghai, 201306 (China)

    2015-12-15

    The experiments described in this work were performed with the aim of introducing a new plasma antenna that was excited by a 5–20 kHz alternating current (AC) power supply, where the antenna was transformed into a U-shape. The results show that the impedance, voltage standing-wave ratio (VSWR), radiation pattern and gain characteristics of the antenna can be controlled rapidly by varying not only the discharge power, but also by varying the discharge frequency in the range from 5 to 20 kHz. When the discharge frequency is adjusted from 10 to 12 kHz, the gain is higher within a relatively broad frequency band and the switch-on time is less than 1 ms when the discharge power is less than 5 W, meaning that the plasma antenna can be turned on and off rapidly.

  9. Experimental investigation of photoresist etching by kHz AC atmospheric pressure plasma jet

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lijun, E-mail: lijunwang@mail.xjtu.edu.cn; Zheng, Yashuang; Wu, Chen; Jia, Shenli

    2016-11-01

    Graphical abstract: Pin-ring electrode, double-ring electrode and multi-electrode kHz AC atmospheric pressure plasma jet were used to etch PR on Si wafer, and a corresponding parametric study was carefully investigated. Display Omitted - Highlights: • The surface roughness increases dramatically after APPJ treatment. • The etch rate of the pin-ring electrode APPJ is the highest than that of the multi-electrode APPJ and the double-ring electrode APPJ. • Ar APPJ has a much higher etch rate and more irregular etch trace than He APPJ. • The effective etching initially increases and then decreases with the increment of plasma jet outlet to PR surface distance. - Abstract: In this study, the mechanism of the photoresist (PR) etching by means of a kHz AC atmospheric pressure plasma jet (APPJ) is investigated. The scanning electron (SEM) and the polarizing microscope are used to perform the surface analysis, and the mechanical profilometry is applied to diagnose the etch rate. The results show that granulated structure with numerous microparticles appears at the substrate surface after APPJ treatment, and the etch rate in the etch center is the fastest and gradually slows down to the edge of etch region. In addition, the pin-ring electrode APPJ has the highest etch rate at but easy to damage the Si wafer, the double-ring APPJ is the most stable but requires long time to achieve the ideal etch result, and the etch rate and the etch result of the multi-electrode APPJ fall in between. Ar APPJ had much higher PR etch rate and more irregular etch trace than He APPJ. It is speculated that Ar APPJ is more energetic and effective in transferring reactive species to the PR surface. It is also observed that the effective etch area initially increases and then decreases as plasma jet outlet to the PR surface distance increases.

  10. Plasma characteristics of argon glow discharge produced by AC power supply operating at low frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Kongpiboolkid, Watcharapon; Mongkolnavin, Rattachat [Department of Physics, Facuty of Science, Chulalongkorn University, Bangkok (Thailand); Plasma Technology and Nuclear Fusion Research Unit, Chulalongkorn University, Bangkok (Thailand)

    2015-04-24

    Non-thermal properties of Argon glow discharge operating with various operating pressures were measured and presented in this work. The Argon plasma is produced by a parallel conducting electrodes coupling with a high voltage AC power supply. The power supply can generate high AC voltage at various frequencies. The frequencies for the operation are in the range of a few kHz. The system is capable of generating electric field between the two metal electrodes discharge system. The characteristics of plasma produced were measured by optical emission spectroscopy (OES) technique where electron temperature (T{sub e}) and electron number density (n{sub e}) can be determined by line intensity ratio method. The value of electron number density was then determined from the Saha-Eggert equation. Our results show that the electron number density of the discharge obtained is of the order of 10{sup −17} − 10{sup −18} m{sup −3} where the electron temperature is between 1.00−2.00 eV for various operating frequencies used which are in good agreement with similar results published earlier.

  11. Multi-Modality Pulsed AC Source for Medical Applications of Non-Equilibrium Plasmas

    Science.gov (United States)

    Friedrichs, Daniel; Gilbert, James

    2014-10-01

    A burgeoning field has developed around the use of non-equilibrium (``cold'') plasmas for various medical applications, including wound treatment, surface sterilization, non-thermal hemostasis, and selective cell destruction. Proposed devices typically utilize pulsed DC power sources, which have no other therapeutic utility, and may encounter significant regulatory restrictions regarding their safety for use in patient care. Additionally, dedicated capital equipment is difficult for healthcare facilities to justify. In this work, we have demonstrated for the first time the generation of non-equilibrium plasma using pulsed AC output from a specially-designed electrosurgical generator. The ability to power novel non-equilibrium plasma devices from a piece of equipment already ubiquitous in operating theatres should significantly reduce the barriers to adoption of plasma devices. We demonstrate the ability of a prototype device, coupled to this source, to reduce bacterial growth in vitro. Such a system could allow a single surgical instrument to provide both non-thermal sterilization and thermal tissue dissection.

  12. On the optical and electrical properties of rf and a.c. plasma polymerized aniline thin films

    Indian Academy of Sciences (India)

    U S Sajeev; C Joseph Mathai; S Saravanan; Rajeev R Ashokan; S Venkatachalam; M R Anantharaman

    2006-04-01

    Polyaniline is a widely studied conducting polymer and is a useful material in its bulk and thin film form for many applications, because of its excellent optical and electrical properties. Pristine and iodine doped polyaniline thin films were prepared by a.c. and rf plasma polymerization techniques separately for the comparison of their optical and electrical properties. Doping of iodine was effected in situ. The structural properties of these films were evaluated by FTIR spectroscopy and the optical band gap was estimated from UV-vis-NIR measurements. Comparative studies on the structural, optical and electrical properties of a.c. and rf polymerization are presented here. It has been found that the optical band gap of the polyaniline thin films prepared by rf and a.c. plasma polymerization techniques differ considerably and the band gap is further reduced by in situ doping of iodine. The electrical conductivity measurements on these films show a higher value of electrical conductivity in the case of rf plasma polymerized thin films when compared to the a.c. plasma polymerized films. Also, it is found that the iodine doping enhanced conductivity of the polymer thin films considerably. The results are compared and correlated and have been explained with respect to the different structures adopted under these two preparation techniques.

  13. Experimental investigation of photoresist etching by kHz AC atmospheric pressure plasma jet

    Science.gov (United States)

    Wang, Lijun; Zheng, Yashuang; Wu, Chen; Jia, Shenli

    2016-11-01

    In this study, the mechanism of the photoresist (PR) etching by means of a kHz AC atmospheric pressure plasma jet (APPJ) is investigated. The scanning electron (SEM) and the polarizing microscope are used to perform the surface analysis, and the mechanical profilometry is applied to diagnose the etch rate. The results show that granulated structure with numerous microparticles appears at the substrate surface after APPJ treatment, and the etch rate in the etch center is the fastest and gradually slows down to the edge of etch region. In addition, the pin-ring electrode APPJ has the highest etch rate at but easy to damage the Si wafer, the double-ring APPJ is the most stable but requires long time to achieve the ideal etch result, and the etch rate and the etch result of the multi-electrode APPJ fall in between. Ar APPJ had much higher PR etch rate and more irregular etch trace than He APPJ. It is speculated that Ar APPJ is more energetic and effective in transferring reactive species to the PR surface. It is also observed that the effective etch area initially increases and then decreases as plasma jet outlet to the PR surface distance increases.

  14. Experimental investigation of SDBD plasma actuator driven by AC high voltage with a superimposed positive pulse bias voltage

    Science.gov (United States)

    Qi, Xiao-Hua; Yan, Hui-Jie; Yang, Liang; Hua, Yue; Ren, Chun-Sheng

    2017-08-01

    In this work, a driven voltage consisting of AC high voltage with a superimposed positive pulse bias voltage ("AC+ Positive pulse bias" voltage) is adopted to study the performance of a surface dielectric barrier discharge plasma actuator under atmospheric conditions. To compare the performance of the actuator driven by single-AC voltage and "AC+ Positive pulse bias" voltage, the actuator-induced thrust force and power consumption are measured as a function of the applied AC voltage, and the measured results indicate that the thrust force can be promoted significantly after superimposing the positive pulse bias voltage. The physical mechanism behind the thrust force changes is analyzed by measuring the optical properties, electrical characteristics, and surface potential distribution. Experimental results indicate that the glow-like discharge in the AC voltage half-cycle, next to the cycle where a bias voltage pulse has been applied, is enhanced after applying the positive pulse bias voltage, and this perhaps is the main reason for the thrust force increase. Moreover, surface potential measurement results reveal that the spatial electric field formed by the surface charge accumulation after positive pulse discharge can significantly affect the applied external electric field, and this perhaps can be responsible for the experimental phenomenon that the decrease of thrust force is delayed by pulse bias voltage action after the filament discharge occurs in the glow-like discharge region. The schlieren images further verify that the actuator-induced airflow velocity increases with the positive pulse voltage.

  15. Studies on the incorporation of lipase in synthetic polymerisable vesicles.

    NARCIS (Netherlands)

    Mosmuller, E.W.J.

    1993-01-01

    This thesis describes studies on the suitability of synthetic polymerisable vesicles for the incorporation and stabilisation of lipase for the bioconversion of organic chemical compounds.In chapter 1 , some characteristics are reviewed of hydrolytic enzymes, and more specific those

  16. Impairment of liver synthetic function and the production of plasma proteins in primary breast cancer patients on doxorubicincyclophosphamide (AC) protocol.

    Science.gov (United States)

    Saleem, Zikria; Ahmad, Mobasher; Hashmi, Furqan Khurshid; Saeed, Hamid; Aziz, Muhammad Tahir

    2016-09-01

    Doxorubicin and Cyclophosphamide (AC protocol) combination is usually considered as a first line therapy in newly diagnosed breast cancer patients. Thus, a retrospective observational study was conducted to monitor the effect of AC protocol on liver synthetic functions and production of plasma proteins in breast cancer patients, reporting to specialized cancer care hospital of Lahore, Pakistan. A total of 75 patients (n=75) on AC protocol with breast cancer were observed in this study. The patient data including age, gender, body surface area, dosage, disease status and laboratory biochemical values were recorded by reviewing historical treatment records. Pre-treatment values were taken as baseline values for albumin, globulin, blood urea nitrogen (BUN), albumin/globulin (A/G) ratio and total proteins. The baseline values were compared after each cycle of by applying ANOVA using statistical tool SPSS® version 21. The plasma levels of blood urea nitrogen (BUN), total protein and globulin dropped significantly (p0.05). The A/G ratio level increased (pliver synthetic functions as observed by decreased blood urea nitrogen (BUN) and plasma protein levels.

  17. Cluster dynamics, growth and syneresis during silica hydrogel polymerisation

    Science.gov (United States)

    Birch, David J. S.; Geddes, Chris D.

    2000-04-01

    The aggregation and syneresis of silica particles during hydrogel polymerisation has been observed in situ for the first time with near-Å resolution using a new approach based on the combined fluorescence anisotropy decay of solvated and bound dye molecules. Primary particles of mean hydrodynamic diameter ˜1.5 nm are found to be present within 20 min of mixing sodium silicate solution and sulphuric acid. Clustering then occurs during siloxane polymerisation to produce after ˜30 h secondary particles with a mean diameter up to ˜4.5 nm at a growth rate which depends on silicate concentration and time to microgelation, tg. Subsequent condensation to ˜4 nm diameter occurs within 1 week as particle syneresis dominates. The effects on particle growth of adding D 2O and inorganic salts are demonstrated.

  18. Polymerisation by acrylamide and acrylic acid inverse suspension

    Directory of Open Access Journals (Sweden)

    Sergio Alejandro LLoreda Blanco

    2010-04-01

    Full Text Available This work describes polymerisation by inverse suspension of acrylamide monomers and acrylic acid for forming homopolymers or copolymers This type of polymersitaion's advantages are described and reasons given for why it should be studied. The article stresses the importance of these types of monomer for obtaining materials presenting great affinity for water, such as super-absorbents and controlled liberation mechanism. Important aspects are presented such as type of initiation, monomer composition and continuous phase composition; parameters are described offering an important basis for formulating a system leading to successfully obtaining the desired materials' most relevant characteristics such as particle distribution and size polymerisation kinetics, conversion and water absorption capacity respecting the system's modifiable parameters. The foregoing is important since the product can be modified, bestowing propierties on it which are suitable for its use.

  19. New developments on the ring opening polymerisation of polylactide

    OpenAIRE

    Jacobsen, Sven; Fritz, Hans-Gerhard; Degée, Philippe; Dubois, Philippe; Jérôme, Robert

    2000-01-01

    Polylactides (PLA), biodegradable aliphatic polyesters, produced solely from renewable resources may substitute petrochemically based polymers in a broad range of applications in the near future, if we manage to produce them at lower cost and higher efficiency as nowadays. Possible applications include food packaging for meat and soft drinks, films for agro-industry and non-wovens in hygienic products. The authors developed, based on a new catalytic system, a reactive extrusion polymerisation...

  20. Two-dimensional model of an AC plasma display panel cell in a neon-xenon mixture

    Energy Technology Data Exchange (ETDEWEB)

    Boeuf, J.P.; Pitchford, L.C. [Universite Paul Sabatier, Toulouse (France)

    1995-12-31

    We present a 2-D fluid model of an AC plasma display panel cell. Plasma Display Panels (PDP) are flat display devices where the light of each picture element is emitted from a plasma created by an electric discharge. In the simplest electrode configuration, AC plasma display panels consist of two glass plates, each with parallel electrodes deposited on their surfaces. The electrodes are covered with a dielectric film above which a protective MgO layer is deposited. The plates are sealed together with their electrodes at right angles, and the cap between the plates is filled with a rare gas mixture. An electric discharge can be initiated in the gas cap by applying a voltage pulse between a line electrode and a column electrode. This discharge is transient due to the dielectric layers covering the electrode: the charges deposited on the dielectric surfaces induce in the gas cap a voltage which opposes the electrode voltage. Since the electrode voltage is AC (frequency in the 10-100 kHz range), a discharge is initiated each time the electrode voltage changes sign (the voltage across the dielectric layers adds to the electrode voltage when it changes sign). The {open_quotes}ON{close_quotes} state of a picture element is therefore a succession of transient discharges. In color displays, the UV light of the discharge is used to excite phosphors in the three fundamental colors (at least three discharge cells are used for one pixel of the screen). Neon-xenon or helium-xenon mixtures are generally used in color displays where photons emitted by excited atomic (147 nm) and molecular (150 nm and 173 nm) xenon are used to excite the phosphors.

  1. Developed Hybrid Model for Propylene Polymerisation at Optimum Reaction Conditions

    Directory of Open Access Journals (Sweden)

    Mohammad Jakir Hossain Khan

    2016-02-01

    Full Text Available A statistical model combined with CFD (computational fluid dynamic method was used to explain the detailed phenomena of the process parameters, and a series of experiments were carried out for propylene polymerisation by varying the feed gas composition, reaction initiation temperature, and system pressure, in a fluidised bed catalytic reactor. The propylene polymerisation rate per pass was considered the response to the analysis. Response surface methodology (RSM, with a full factorial central composite experimental design, was applied to develop the model. In this study, analysis of variance (ANOVA indicated an acceptable value for the coefficient of determination and a suitable estimation of a second-order regression model. For better justification, results were also described through a three-dimensional (3D response surface and a related two-dimensional (2D contour plot. These 3D and 2D response analyses provided significant and easy to understand findings on the effect of all the considered process variables on expected findings. To diagnose the model adequacy, the mathematical relationship between the process variables and the extent of polymer conversion was established through the combination of CFD with statistical tools. All the tests showed that the model is an excellent fit with the experimental validation. The maximum extent of polymer conversion per pass was 5.98% at the set time period and with consistent catalyst and co-catalyst feed rates. The optimum conditions for maximum polymerisation was found at reaction temperature (RT 75 °C, system pressure (SP 25 bar, and 75% monomer concentration (MC. The hydrogen percentage was kept fixed at all times. The coefficient of correlation for reaction temperature, system pressure, and monomer concentration ratio, was found to be 0.932. Thus, the experimental results and model predicted values were a reliable fit at optimum process conditions. Detailed and adaptable CFD results were capable

  2. Bonding auto-polymerising acrylic resin to acrylic denture teeth.

    LENUS (Irish Health Repository)

    Nagle, Susan

    2009-09-01

    This study investigated the effect of surface treatments on the shear bond strength of an auto-polymerising acrylic resin cured to acrylic denture teeth. The surface treatments included a combination of grit-blasting and\\/or wetting the surface with monomer. Samples were prepared and then stored in water prior to shear testing. The results indicated that the application of monomer to the surface prior to bonding did not influence the bond strength. Grit blasting was found to significantly increase the bond strength.

  3. Characterization of plasma electrolytic oxidation coatings on Zircaloy-4 formed in different electrolytes with AC current regime

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Yingliang, E-mail: chengyingliang@hnu.edu.cn [College of Materials Science and Engineering, Hunan University, Changsha 410082 (China); Matykina, Enzhe [Dpt. Ciencia de los Materiales e Ingenieria Metalurgica, Facultad de Ciencias Quimicas, Universidad Complutense de Madrid, Madrid 28040 (Spain); Skeldon, Peter; Thompson, George [Corrosion and Protection Centre, School of Materials, University of Manchester, Sackville Street, Manchester M13 9PL (United Kingdom)

    2011-10-01

    Highlights: > ZrO{sub 2} coatings are grown on Zircaloy-4 by AC plasma electrolytic oxidation. > Tetragonal and monoclinic ZrO{sub 2} are formed using silicate electrolyte. > Pyrophosphate electrolyte results in flawed coatings of monoclinic ZrO{sub 2}. > Silicate favours formation of tetragonal ZrO{sub 2}, with coating hardness {approx}8 GPa. > Microstructures are related to temperature gradients and solidification rates. - Abstract: Plasma electrolytic oxidation was undertaken on Zircaloy-4 in alkaline silicate and pyrophosphate electrolytes, with a square waveform AC current regime. The resultant coatings were examined using scanning electron spectroscopy, X-ray diffraction and nanoindentation. The coatings formed in silicate electrolyte comprised mainly a porous inner layer and a more compact outer layer, with characteristic solidification structures being evident following prolonged treatment. The coatings contained monoclinic and tetragonal ZrO{sub 2}, the latter being mainly present in the outer layer, which was of hardness up to {approx}8 GPa. In contrast, extensively cracked coatings resulted from use of pyrophosphate electrolyte; the coating integrity was improved by the addition of silicate to the pyrophosphate electrolyte. The different morphologies of the coatings appeared to be related to the differing nature of the microdischarges and to the incorporation of silicon species that enhanced the formation of t-ZrO{sub 2}.

  4. Polymerisation of Beta-alanine through catalytic ester-amide exchange

    NARCIS (Netherlands)

    Steunenberg, P.; Könst, P.M.; Scott, E.L.; Franssen, M.C.R.; Zuilhof, H.; Sanders, J.P.M.

    2013-01-01

    Herein we present the use of group (IV) metal alkoxides as catalysts for the polymerisation of esters of p-alanine and its derivatives. The influence of different group (IV) metal alkoxides, different esters, temperature and solvents on the polymerisation are investigated. The order in which the gro

  5. Metallocene supported core@LDH catalysts for slurry phase ethylene polymerisation.

    Science.gov (United States)

    Buffet, Jean-Charles; Byles, Coral F H; Felton, Ryan; Chen, Chunping; O'Hare, Dermot

    2016-03-14

    We report the synthesis of solid catalysts based on a zirconocene supported on either silica@AMO-LDH or zeolite@AMO-LDH for the slurry phase polymerisation of ethylene. The hybrid catalysts demonstrate synergistic effects in which the polymerisation activity is up to three times higher than the zirconocene supported on analogous single phase silica or zeolite supports.

  6. Zirconium and hafnium Salalen complexes in isospecific polymerisation of propylene.

    Science.gov (United States)

    Press, Konstantin; Venditto, Vincenzo; Goldberg, Israel; Kol, Moshe

    2013-07-07

    The activity of dibenzylzirconium and dibenzylhafnium Salalen complexes in polymerisation of propylene with MAO as a cocatalyst is described. Three Salalen ligand precursors combining a bulky alkyl group (1-adamantyl) on the imine-side phenol and electron withdrawing halo groups of different sizes on the amine-side phenol were explored. All metal complexes were obtained as single diastereomers. An X-ray crystallographic structure of a hafnium complex of an additional ligand carrying the combination of tert-butyl and chloro substituted phenolates, 4-Hf, revealed a fac-mer wrapping of the Salalen ligand around the metal centre. All complexes led to active catalysts in propylene polymerisation and to isotactic polypropylene of high regioregularity. The zirconium complexes led to polypropylene having molecular weights of Mw = 132,000-200,000 and isotacticities of [mmmm] = 65.7-75.0%. The hafnium complexes led to polypropylene of higher molecular weights of Mw = 375,000-520,000 and higher stereoregularities of [mmmm] = 80.6-89.3%, the highest isotacticity obtained with 3-Hf.

  7. Reuse of spent bleaching earth by polymerisation of residual organics.

    Science.gov (United States)

    Beshara, Abdelhamid; Cheeseman, Christopher R

    2014-10-01

    Spent bleaching earth (SBE) is a waste generated by the edible oil industry that currently has limited options for beneficial reuse. In excess of ∼2 million tonnes per year of SBE is generated world-wide with major quantities available in the middle-east where significant volumes of edible oils are produced. Low pressure compaction followed by heat treatment at 150°C causes polymerisation of the residual organic components in SBE and this produces monolithic samples with high unconfined compressive strengths (54MPa). SBE can therefore be used to manufacture novel clay blocks for use in construction that are bonded by polymerised vegetable oil. This represents a new, innovative and resource efficient application for SBE. In this research, commercial SBE has been characterised and the effects of key processing variables (temperature and compaction pressure) on the compressive strength, porosity and density of the SBE clay blocks are reported and the mechanisms responsible for strength development are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. AC plasma induced modifications in Sb{sub 2}S{sub 3} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Calixto-Rodriguez, M; Martinez, H [Instituto de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, Apartado Postal 48-3, 62210, Cuernavaca, Morelos (Mexico); Castillo, F [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, 04510, Mexico D. F. (Mexico); Pena, Y [Universidad Autonoma de Nuevo Leon, Facultad de Ciencias Quimicas, Pedro de Alba s/n, Cd. Universitaria, San Nicolas de los Garza, N.L (Mexico); Sanchez-Juarez, A, E-mail: ciro@nucleares.unam.m [Centro de Investigacion en EnergIa, Universidad Nacional Autonoma de Mexico, Privada Xochicalco s/n Col. Centro, Temixco, Morelos, C.P. 62580 (Mexico)

    2010-01-01

    Sb{sub 2}S{sub 3} thin films, deposited by the chemical bath deposition method, were treated with N{sub 2} plasma at 3.0 Torr during several minutes. The as-prepared Sb{sub 2}S{sub 3} thin films and films treated with N{sub 2} plasma have been characterized using several techniques. X-ray diffraction studies have shown that plasma treatment induced recrystallization on the as-prepared Sb{sub 2}S{sub 3}thin films. The band gap values decreased from 2.37 to 1.82 eV after plasma treatment, and the electrical conductivity increased from 10{sup 9} to 10{sup 7} ({Omega}cm){sup -1} due to the annealing effect.

  9. Nanoscale precision of 3D polymerisation via polarisation control

    CERN Document Server

    Rekstyte, Sima; Gailevicius, Darius; Malinauskas, Mangirdas; Mizeikis, Vygantas; Gamaly, Eugene G; Juodkazis, Saulius

    2016-01-01

    A systematic analysis of polarization effects in a direct write femtosecond laser 3D lithography is presented. It is newly shown that coupling between linear polarization of the writing light electric field and temperature gradient can be used to fine-tune feature sizes in structuring of photoresists at a nanoscale. The vectorial Debye focusing is used to simulate polarization effects and a controlled variation up to 20% in the linewidth is shown experimentally for the identical axial extent of the polymerised features. The revealed mechanisms are relevant for a wide range of phenomena of light-matter interaction at tight focusing in laser-tweezers and in plasmonic or dielectric sub-wavelength focusing where strong light intensity and thermal gradients coexist.

  10. MWD design in a series of CSTRs with living polymerisation reactions

    National Research Council Canada - National Science Library

    Eszter Farkas; Zsolt György Meszéna

    2010-01-01

    ...) of living polymerisation processes in various reactor configurations, ii) and - in a reversed calculation process - to design reactor parameters and feed profiles for a single CSTR or a tubular reactor to meet a target...

  11. Enzymatic polymerisation and effect of fractionation of dissolved lignin from Eucalyptus globulus Kraft liquor.

    Science.gov (United States)

    Gouveia, S; Fernández-Costas, C; Sanromán, M A; Moldes, D

    2012-10-01

    The potential ability of the laccase from Myceliophthora thermophila, either alone or with low molecular weight (LMW) additives, to polymerise a dissolved lignin from Kraft liquor of eucalypt cooking was investigated. A previous study of enzymatic performance (activity and stability) was carried out using a design experiment methodology. In addition, Kraft dissolved lignin (KDL) was fractionated according to two different protocols (solvent extraction and acidic fractionation) in order to identify possible lignin fractions with noticeable polymerisation ability. KDL and its corresponding lignin fractions were treated with laccase and analysed by size exclusion chromatography and Fourier transform infrared spectroscopy. The results provide conclusive evidence of notable lignin modifications after incubation with laccase. Moreover, lignin fractionation allows to obtain lignin fractions with different chemical characteristics and polymerisation capability. Depending on the type of raw lignin, molecular weight can increase from 4- to 21-fold by means of laccase polymerisation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Effect of gold nanorods in an MgO protective layer of AC plasma display panels.

    Science.gov (United States)

    Cho, Seok Ho; Lee, Seong Min; Kim, Woo Hyun; Choi, Kyung Cheol

    2015-04-15

    We propose a modified MgO protective layer for alternating current plasma display panels. The modified MgO protective layer of the panel tested here has a structure that incorporates silica-coated Au nanorods (NRs), leading to localized surface plasmon resonance (LSPR) in the near-infrared (IR) region. The silica-coated Au NRs were synthesized by a simple chemical method and inserted into an MgO protective layer using an air-spray method. The operating voltage of the proposed structure was decreased by 10 V. The luminance and luminous efficacy of the test panel part with the silica-coated Au NRs both increased by about 15%. According to the measured results of the IR response time, the sustain discharge time lag was reduced. In addition, by inserting the silica-coated Au NRs into the MgO protective layer, a decrease of the IR emission proceeding from the plasma discharge was acquired. Finally, we investigated the LSPR effect of the silica-coated Au NRs in a simulation with a finite-difference time domain method.

  13. Polymer coatings on plane and spherical surfaces obtained by plasma polymerization from trans-2-butene and hydrogen mixture; Depots de polymere sur surfaces planes et spheriques obtenus par polymerisation plasma a partir d`un melange de trans-2-butene et d`hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    Benardais, A

    1997-10-21

    This study of a low frequency plasma polymerization process was undertaken to be used in manufacturing of targets used in laser-matter interaction experiments. In this system, whether the sample is placed in the discharge or outside of the discharge, hydrocarbon coatings from a gaseous mixture of hydrogen and trans-2-butene are obtain. This study consists of two parts. We first dealt with the understanding of plasma polymerization mechanisms in the reactor which resulted in a better process optimization. The study of gas flow in the reactor allowed us to determine the species repartition in the vessel. With experiments performed on the electrical behavior in the reactor we were able to define the discharge type. Then, species present in the plasma were analysed by emission spectroscopy and mass spectrometry and then reaction mechanisms were proposed. Attention was paid to the role of hydrogen which in fact acted as a reagent like trans-2-butene. We also worked on the process optimization in order to obtain a good working point which produces coatings which are as transparent as possible, contain only carbon and hydrogen (and the least amount of oxygen), have a smooth surface finish (mean square root of roughness < 50 nm) and retain their qualities overtime. After the reactor characterization, the study of the effects of different parameters (inner or post-discharge coatings, pressure, total gas flow, composition of the mixture of trans-2-butene and hydrogen, power, frequency, interelectrode distance) on deposition rate, roughness and chemical composition of coatings led to the finding of optimal deposition conditions. (author) 103 refs.

  14. Needle-array to Plate DBD Plasma Using Sine AC and Nanosecond Pulse Excitations for Purpose of Improving Indoor Air Quality.

    Science.gov (United States)

    Zhang, Li; Yang, Dezheng; Wang, Wenchun; Wang, Sen; Yuan, Hao; Zhao, Zilu; Sang, Chaofeng; Jia, Li

    2016-04-29

    In this study, needle-array to plate electrode configuration was employed to generate an atmospheric air diffuse discharge using both nanosecond pulse and sine AC voltage as excitation voltage for the purpose of improving indoor air quality. Different types of voltage sources and electrode configurations are employed to optimize electrical field distribution and improve discharge stability. Discharge images, electrical characteristics, optical emission spectra, and plasma gas temperatures in both sine AC discharge and nanosecond pulse discharge were compared and the discharge stability during long operating time were discussed. Compared with the discharge excited by sine AC voltage, the nanosecond pulsed discharge is more homogenous and stable, besides, the plasma gas temperature of nanosecond pulse discharge is much lower. Using packed-bed structure, where γ- Al2O3 pellets are filled in the electrode gap, has obvious efficacy in the production of homogenous discharge. Furthermore, both sine AC discharge and nanosecond pulse discharge were used for removing formaldehyde from flowing air. It shows that nanosecond pulse discharge has a significant advantage in energy cost. And the main physiochemical processes for the generation of active species and the degradation of formaldehyde were discussed.

  15. Needle-array to Plate DBD Plasma Using Sine AC and Nanosecond Pulse Excitations for Purpose of Improving Indoor Air Quality

    Science.gov (United States)

    Zhang, Li; Yang, Dezheng; Wang, Wenchun; Wang, Sen; Yuan, Hao; Zhao, Zilu; Sang, Chaofeng; Jia, Li

    2016-04-01

    In this study, needle-array to plate electrode configuration was employed to generate an atmospheric air diffuse discharge using both nanosecond pulse and sine AC voltage as excitation voltage for the purpose of improving indoor air quality. Different types of voltage sources and electrode configurations are employed to optimize electrical field distribution and improve discharge stability. Discharge images, electrical characteristics, optical emission spectra, and plasma gas temperatures in both sine AC discharge and nanosecond pulse discharge were compared and the discharge stability during long operating time were discussed. Compared with the discharge excited by sine AC voltage, the nanosecond pulsed discharge is more homogenous and stable, besides, the plasma gas temperature of nanosecond pulse discharge is much lower. Using packed-bed structure, where γ- Al2O3 pellets are filled in the electrode gap, has obvious efficacy in the production of homogenous discharge. Furthermore, both sine AC discharge and nanosecond pulse discharge were used for removing formaldehyde from flowing air. It shows that nanosecond pulse discharge has a significant advantage in energy cost. And the main physiochemical processes for the generation of active species and the degradation of formaldehyde were discussed.

  16. Polymerisation shrinkage versus layer thickness of a dentine bonding resin: Method development

    Directory of Open Access Journals (Sweden)

    Jafarzadeh T

    2002-07-01

    Full Text Available Dentine bonding systems are usually unfilled, and so their shrinkage may be significant. High"nshrinkage may cause internal stress at the interface between resin-composite restoration and the dentine"nsubstrate. Failure of the adhesive interface may be observed due to the interna! stress. The aims of this"nstudy were:"nA To obtain a suitable method for measuring the kinetics of polymerisation shrinkage in unfilled resm at different thicknesses, particularly for thin films."nB Consideraing the effect of thickness on shrinkage."nScotchbond Multipurpose (3M adhesive bond resin was used. To overcome the particular challenges presented by thin films, a filled-ring measurement procedure was used. Also, a non-contact laser analogue displacement sensor system was developed and applied to measure polymerisation shrinkage. Regression analysis was performed on a complete data set. Non-linear regression analysis established a logarithmic relationship between polymerisation shrinkage and layer thickness. The method applied in this study was found to be sensitive and accurate procedure for determining photo-polymerisation shrinkage of thin films. Polymerisation shrinkage increased with logarithmic of the adhesive thickness.

  17. Experimental Investigation of Separation Control on a NACA0024 Airfoil using Stationary and Non-Stationary AC-Dielectric Barrier Discharge Plasma Actuator

    Directory of Open Access Journals (Sweden)

    Hossein Parishani

    2016-01-01

    Full Text Available An experimental study of stationary and non-stationary dielectric barrier discharge (DBD plasma actuator is presented to control the flow around a NACA0024 airfoil. First, an induced air velocity of ~5 m/s is generated on a flat plate in still air using an AC-DBD actuator to find the optimal setup of the actuator (voltage, frequency, electrode width and gap size. Using the same actuator in the optimal position/setup on a NACA0024 airfoil at Reynolds number of 0.48×106, we are able to increase the stall angle of the airfoil to 18º, compared to 16º in no-actuator state. Furthermore, during the plasma actuation, the lift is increased by up to 5%. We show that non-stationary actuation, while yielding a performance similar to stationary actuation, leads to a considerable reduction of ~51% in plasma power consumption.

  18. Investigation of an accident in a resins manufacturing site: the role of accelerator on polymerisation of methyl methacrylate.

    Science.gov (United States)

    Casson, Valeria; Snee, Tim; Maschio, Giuseppe

    2014-04-15

    This paper analyzes the effect of an accelerator on the polymerisation of methyl methacrylate (MMA). This study is based on the results of an investigation of an accident in a manufacturing site for resins located in the United Kingdom. As sequence of event to cause the accident the following was assumed: during an unattended batch process a runaway undesired polymerisation of methyl methacrylate occurred, generating rapid vaporisation of monomer, which in contact with an ignition source, led to an explosion followed by a fire. Since no initiator for the polymerisation reaction had been jet added to the blend, it was supposed that the accelerator contributed to the onset of the undesired polymerisation. The accelerator involved in the accident t has therefore been tested by differential scanning calorimetry and adiabatic calorimetry. The experimental data allowed the authors to prove the hypothesis made and to define safety ranges for the polymerisation reaction.

  19. Association of CYP7A1 -278A>C polymorphism and the response of plasma triglyceride after dietary intervention in dyslipidemic patients.

    Science.gov (United States)

    Barcelos, A L V; Chies, R; Almeida, S E M; Fiegenbaum, M; Schweigert, I D; Chula, F G L; Rossetti, M L; Silva, C M D

    2009-06-01

    We investigated the effect of the -278A>C polymorphism in the CYP7A1 gene on the response of plasma lipids to a reduced-fat diet for 6 to 8 weeks in a group of 82 dyslipidemic males with a mean age of 46.0 +/- 11.7 years. Individuals who presented at least one high alteration in total cholesterol, low-density lipoprotein cholesterol or triglyceride values were considered to be dyslipidemic. Exclusion criteria were secondary dyslipidemia due to diabetes mellitus, renal, liver, or thyroid disease. None of the subjects were using lipid-lowering medication. Baseline and follow-up lipid concentrations were measured. The genotypes were determined by the digestion of PCR products with the BsaI restriction endonuclease. There were statistically significant reductions in plasma total cholesterol, low-density lipoprotein cholesterol and triglyceride concentrations after dietary intervention. The minor allele C has a frequency of 43%. Carriers of the C allele had significantly lower triglyceride concentrations (P = 0.02) than AA homozygotes. After adjustment of covariates, subjects with the AC and CC genotypes showed a greater reduction in triglyceride concentrations compared to subjects with the AA genotype. Multiple linear regression analyses showed that the AC and CC CYP7A1 genotypes accounted for 5.2 and 6.2% of triglyceride concentration during follow-up and adjusted percent of change of triglyceride concentration, respectively. The present study provides evidence that -278A>C polymorphism in the CYP7A1 gene can modify triglyceride concentrations in response to a reduced fat diet in a dyslipidemic male population. This gene represents a potential locus for a nutrigenetic directed approach.

  20. Association of CYP7A1 -278A>C polymorphism and the response of plasma triglyceride after dietary intervention in dyslipidemic patients

    Directory of Open Access Journals (Sweden)

    A.L.V. Barcelos

    2009-06-01

    Full Text Available We investigated the effect of the -278A>C polymorphism in the CYP7A1 gene on the response of plasma lipids to a reduced-fat diet for 6 to 8 weeks in a group of 82 dyslipidemic males with a mean age of 46.0 ± 11.7 years. Individuals who presented at least one high alteration in total cholesterol, low-density lipoprotein cholesterol or triglyceride values were considered to be dyslipidemic. Exclusion criteria were secondary dyslipidemia due to diabetes mellitus, renal, liver, or thyroid disease. None of the subjects were using lipid-lowering medication. Baseline and follow-up lipid concentrations were measured. The genotypes were determined by the digestion of PCR products with the BsaI restriction endonuclease. There were statistically significant reductions in plasma total cholesterol, low-density lipoprotein cholesterol and triglyceride concentrations after dietary intervention. The minor allele C has a frequency of 43%. Carriers of the C allele had significantly lower triglyceride concentrations (P = 0.02 than AA homozygotes. After adjustment of covariates, subjects with the AC and CC genotypes showed a greater reduction in triglyceride concentrations compared to subjects with the AA genotype. Multiple linear regression analyses showed that the AC and CC CYP7A1 genotypes accounted for 5.2 and 6.2% of triglyceride concentration during follow-up and adjusted percent of change of triglyceride concentration, respectively. The present study provides evidence that -278A>C polymorphism in the CYP7A1 gene can modify triglyceride concentrations in response to a reduced fat diet in a dyslipidemic male population. This gene represents a potential locus for a nutrigenetic directed approach.

  1. Polymorphism and polymerisation of acrylic and methacrylic acid at high pressure

    DEFF Research Database (Denmark)

    Oswald, Iain D. H.; Urquhart, Andrew J.

    2011-01-01

    The polymorphism and polymerisation of two related acids have been investigated under high pressure conditions. Acrylic acid crystallises as a new polymorph at 0.65 GPa whilst methacrylic acid crystallises in a new polymorph at a higher pressure of 1.5 GPa. Both these new polymorphs exhibit similar...

  2. C1 polymerisation and related C-C bond forming ‘carbene insertion’ reactions

    NARCIS (Netherlands)

    Jellema, E.; Jongerius, A.L.; Reek, J.N.H.; de Bruin, B.

    2010-01-01

    In this critical review we summarise the currently available ‘C1 polymerisation’ techniques as valuable alternatives for ‘C2 polymerisation’ in the preparation of saturated main-chain carbon-based polymers. C1 polymerisation involves the growth of polymers from monomers delivering only one

  3. Estudio por emisión acústica del comportamiento a flexión de recubrimientos WC-Co obtenidos por plasma atmosférico

    Directory of Open Access Journals (Sweden)

    Segovia, F.

    2007-12-01

    Full Text Available Plasma sprayed cermet coatings WC-Co are used in a wide range of industrial applications, mainly due to their wear resistance even in corrosive environments. The objective of this work is to analyze mechanical response of hard metal coatings by means of three- and four-points bend tests applying acoustic emission technique to determine failure critical strength. It has been observed the effect of supported charge level in structural damage by means of optical microscopy and scanning electron microscopy. Acoustic emission has allowed us to relate damage level to stresses level and then to understand coatings failure mechanism.

    Los recubrimientos de cermet WC-Co proyectados por plasma se utilizan en un amplio rango de aplicaciones industriales, principalmente por su resistencia al desgaste, incluso en medio corrosivo. El objetivo de este trabajo es analizar la respuesta mecánica de los recubrimientos de metal duro mediante ensayos de flexión a 3 y 4 puntos aplicando el método de emisión acústica para determinar las tensiones críticas de fallo. Se ha observado el efecto del nivel de carga soportado en el dañado estructural mediante microscopia óptica y electrónica de barrido. La emisión acústica ha permitido relacionar el grado de dañado con el nivel de tensiones y, así, entender el mecanismo de fallo de los recubrimientos.

  4. Pd-catalysed direct arylation polymerisation for synthesis of low-bandgap conjugated polymers and photovoltaic performance.

    Science.gov (United States)

    Chang, Shu-Wei; Waters, Huw; Kettle, Jeff; Kuo, Zi-Rui; Li, Chun-Han; Yu, Chin-Yang; Horie, Masaki

    2012-11-23

    Low-bandgap conjugated copolymers based on a donor-acceptor structure have been synthesised via palladium-complex catalysed direct arylation polymerisation. Initially, we report the optimisation of the synthesis of poly(cyclopentadithiophene-alt-benzothiadiazole) (PCPDTBT) formed between cyclopentadithiophene and dibromobenzothiadiazole units. The polymerisation condition has been optimised, which affords high-molecular-weight polymers of up to M(n) = 70 k using N-methylpyrrolidone as a solvent. The polymers are used to fabricate organic photovoltaic devices and the best performing PCPDTBT device exhibits a moderate improvement over devices fabricated using the related polymer via Suzuki coupling. Similar polymerisation conditions have also been applied for other monomer units.

  5. Optical properties of the atmospheric pressure helium plasma jet generated by alternative current (a.c.) power supply

    Science.gov (United States)

    Ilik, Erkan; Akan, Tamer

    2016-05-01

    In this work, an atmospheric pressure plasma jet (APPJ) was produced to generate cold flowing post-discharge plasma of pure helium gas. The main aim of this study was to generate cold flowing APPJ of pure helium gas and to determine how their optical emission spectrum change influences varying different flow rates. Lengths of early, middle, and late post-discharge plasma (jet) regions and their fluctuations were determined, respectively. Then, ignition condition dependence of the post-discharge plasma for flow rate was specified at a constant voltage. Spectroscopic studies of an atmospheric pressure plasma jet of helium were presented via analyzing OH, N2, N2+, oxygen, and helium intensities for various flow rates.

  6. Adaptive control using a hybrid-neural model: application to a polymerisation reactor

    Directory of Open Access Journals (Sweden)

    Cubillos F.

    2001-01-01

    Full Text Available This work presents the use of a hybrid-neural model for predictive control of a plug flow polymerisation reactor. The hybrid-neural model (HNM is based on fundamental conservation laws associated with a neural network (NN used to model the uncertain parameters. By simulations, the performance of this approach was studied for a peroxide-initiated styrene tubular reactor. The HNM was synthesised for a CSTR reactor with a radial basis function neural net (RBFN used to estimate the reaction rates recursively. The adaptive HNM was incorporated in two model predictive control strategies, a direct synthesis scheme and an optimum steady state scheme. Tests for servo and regulator control showed excellent behaviour following different setpoint variations, and rejecting perturbations. The good generalisation and training capacities of hybrid models, associated with the simplicity and robustness characteristics of the MPC formulations, make an attractive combination for the control of a polymerisation reactor.

  7. Pattern formation in polymerising actin flocks: spirals, spots and waves without nonlinear chemistry

    CERN Document Server

    Goff, Thomas Le; Marenduzzo, Davide

    2016-01-01

    We propose a model solely based on actin treadmilling and polymerisation which describes many characteristic states of actin wave formation: spots, spirals and travelling waves. In our model, as in experiments on cell recovering motility following actin depolymerisation, we choose an isotropic low density initial condition; polymerisation of actin filaments then raises the density towards the Onsager threshold where they align. We show that this alignment, in turn, destabilizes the isotropic phase and generically induces transient actin spots or spirals as part of the dynamical pathway towards a polarized phase which can either be uniform or consist of a series of actin-wave trains (flocks). Our results uncover a universal route to actin wave formation in the absence of any system specific nonlinear biochemistry, and it may help understand the mechanism underlying the observation of actin spots and waves in vivo. They also suggest a minimal setup to design similar patterns in vitro.

  8. Diagnostics of an AC driven atmospheric pressure non-thermal plasma jet and its use for radially directed jet array

    Science.gov (United States)

    Zhu, W.; Wang, R.

    2017-08-01

    An alternating current atmospheric pressure plasma jet is generated with noble gas or noble gas/oxygen admixture as working gas. A "core plasma filament" is observed at the center of the dielectric tube and extends to the plasma jet at higher peak-to-peak voltages. This type of plasma jet is believed to be of the same nature with the reported plasma bullet driven by pulsed DC power sources. Double current probes are used to assess the speed of the plasma bullet and show that the speed is around 104-105 m/s. The time dependence of the downstream bullet speed is attributed to the gas heating and in turn the increase of the reduced electric field E/N. Optical emission spectra show the dependence of helium and oxygen emission intensities on the concentration of oxygen additive in the carrier gas, with peak values found at 0.5% O2. Multiple radial jets are realized on dielectric tubes of different sizes. As a case study, one of these multi-jet devices is used to treat B. aureus on the inner surface of a plastic beaker and is shown to be more effective than a single jet.

  9. Metal-catalysed organic transformations in water: From bromination to polymerisation

    Indian Academy of Sciences (India)

    Manish Bhattacharjee; Braja N Patra

    2006-11-01

    Reaction of ,-unsaturated aromatic carboxylic acids with KBr and H2O2 in the presence of Na2MoO4$\\cdot$H2O in aqueous medium affords -bromo alkenes in high yields. Metallocene dichlorides, Cp2MCl2 (M = Ti, Zr, or V) catalyse polymerisation of olefins in aqueous medium to afford high molecular weight polymers with low molecular weight distribution.

  10. High internal phase emulsions (HIPEs) and polymerised HIPEs (PolyHIPEs)

    CERN Document Server

    Cameron, N R

    1995-01-01

    High internal phase emulsions (HIPEs) possess an internal phase volume ratio (phi) greater than 0.74. Novel non-aqueous HIPEs can be obtained from a non-polar organic liquid, such as petroleum ether, dispersed in a highly polar medium, such as formamide or dimethylsulfoxide. The system is stabilised with block copolymer surfactants of suitable HLB number. Polymerisation of a HIPE continuous phase leads to a highly porous monolithic material known as PolyHIPE. These polymers often have a completely open-cellular structure. The mechanism for the formation of this morphology was elucidated by performing scanning electron microscopy (SEM) on frozen HIPE samples at various stages of polymerisation. The point of transition from emulsion to open-cell polymer was found to coincide with the gel-point of the system, implying that the interconnected structure forms as a result of contraction of the continuous phase thin films on polymerisation. Novel PolyHIPE materials have been prepared by chemical modification of cros...

  11. Modified drug release using atmospheric pressure plasma deposited siloxane coatings

    Science.gov (United States)

    Dowling, D. P.; Maher, S.; Law, V. J.; Ardhaoui, M.; Stallard, C.; Keenan, A.

    2016-09-01

    This pilot study evaluates the potential of atmospheric plasma polymerised coatings to modify the rate of drug release from polymeric substrates. The antibiotic rifampicin was deposited in a prototype multi-layer drug delivery system, consisting of a nebulized layer of active drug between a base layer of TEOS deposited on a plastic substrate (polystyrene) and an overlying layer of plasma polymerised PDMS. The polymerised TEOS and PDMS layers were deposited using a helium atmospheric plasma jet system. Elution of rifampicin was measured using UV-VIS spectroscopy, in addition to a antimicrobial well diffusion assay with an established indicator organism. The multi-layered plasma deposited coatings significantly extended the duration of release of the rifampicin from 24 h for the uncoated polymer to 144 h for the coated polymer.

  12. Plasma polymer coatings to aid retinal pigment epithelial growth for transplantation in the treatment of age related macular degeneration.

    Science.gov (United States)

    Kearns, Victoria; Mistry, Anita; Mason, Sharon; Krishna, Yamini; Sheridan, Carl; Short, Robert; Williams, Rachel L

    2012-08-01

    Subretinal transplantation of functioning retinal pigment epithelial (RPE) cells grown on a synthetic substrate is a potential treatment for age-related macular degeneration (AMD), a common cause of irreversible vision loss in developed countries. Plasma polymers give the opportunity to tailor the surface chemistry of the artificial substrate whilst maintaining the bulk properties. In this study, plasma polymers with different functionalities were investigated in terms of their effect on RPE attachment and growth. Plasma polymers of acrylic acid (AC), allyl amine (AM) and allyl alcohol (AL) were fabricated and characterised using X-ray photoelectron spectroscopy (XPS) and water contact angle measurements. Octadiene (OD) hydrocarbon films and tissue culture polystyrene were used as controls. Wettability varied from hydrophobic OD to relatively hydrophilic AC. XPS demonstrated four very different surfaces with the expected functionalities. Attachment, proliferation and morphological examination of an RPE cell line and primary RPE cells were investigated. Both cell types grew on all surfaces, with the exception of OD, although the proliferation rate of primary cells was low. Good epithelial morphology was also demonstrated. Plasma polymerised films show potential as cell carrier surfaces for RPE cells in the treatment of AMD.

  13. Advances in the development of new catalysts for ethylene and α-olefin polymerisation

    Science.gov (United States)

    Ivanchev, Sergei S.

    2007-07-01

    The role of catalyst systems in the perfection of polymerisation processes and the improvement of the performance characteristics of polyethylene and other polyolefins is considered. The scope of application of post-metallocene catalysts based on transition metal α-diimine, bis(imino)pyridine and phenoxy imine complexes designed in the last decade is analysed. The structures of complexes depending on the type of ligands are described systematically. The development of research into these catalyst systems is discussed, the optimal structures as regards the activity and selectivity are mentioned, and the mechanism of their action and the prospects for industrial use are demonstrated.

  14. Characterisation and quality assessment of binding sites on a propazine-imprinted polymer prepared by precipitation polymerisation.

    Science.gov (United States)

    Cacho, C; Turiel, E; Martin-Esteban, A; Pérez-Conde, C; Cámara, C

    2004-04-01

    In this paper, the Langmuir-Freundlich isotherm (LF) is used to characterise a propazine-imprinted polymer obtained by precipitation polymerisation (MIP-P). Different rebinding studies were carried out allowing to explain the different interactions taking place between the molecularly imprinted polymer and six triazinic herbicides (desisopropylatrazine, desethylatrazine, simazine, atrazine, propazine and prometryn). The LF fitting parameters obtained (total number of binding sites, heterogeneity index and mean binding affinity) were compared to those obtained in a previous work for a propazine-imprinted polymer prepared by bulk polymerisation (MIP-B). From that study, it was concluded that precipitation polymerisation yielded polymers with a more homogeneous binding site distribution and higher affinity constants.

  15. Compositional Changes for Reduction of Polymerisation-Induced Shrinkage in Holographic Photopolymers

    Directory of Open Access Journals (Sweden)

    D. Cody

    2016-01-01

    Full Text Available Polymerisation-induced shrinkage is one of the main reasons why many photopolymer materials are not used for certain applications including holographic optical elements and holographic data storage. Here, two compositional changes for the reduction of shrinkage in an acrylamide-based photopolymer are reported. A holographic interferometric technique was used to study changes in the dynamics of the shrinkage processes occurring in the modified photopolymer during holographic recording in real time. Firstly, the effect of the replacement of the acrylamide monomer in the photopolymer composition with a larger monomer molecule, diacetone acrylamide, on polymerisation-induced shrinkage has been studied. A reduction in relative shrinkage of 10–15% is obtained using this compositional change. The second method tested for shrinkage reduction involved the incorporation of BEA-type zeolite nanoparticles in the acrylamide-based photopolymer. A reduction in relative shrinkage of 13% was observed for acrylamide photopolymer layers doped with 2.5% wt. BEA zeolites in comparison to the undoped photopolymer.

  16. Organometallic Catalysis in Diene and Cyclo-olefin Polymerisation Processes. II. The Metathesis Reaction in Polymer Chemistry

    Science.gov (United States)

    Dolgoplosk, B. A.; Korshak, Yu V.

    1984-01-01

    The development of ideas concerning the mechanism of the metathesis reaction and its employment in polymer chemistry are examined. The possible applications of the metathesis reaction in the synthesis of polymers by the polymerisation of cycloolefins and cyclodienes with ring opening and via the degradation of high-molecular-weight rubbers and their modification are discussed. The bibliography includes 160 references.

  17. Synthesis of novel glycopolymer brushes via a combination of RAFT-mediated polymerisation and ATRP

    Directory of Open Access Journals (Sweden)

    Eric T.A. van den Dungen

    2011-03-01

    Full Text Available Glycopolymers (synthetic sugar-containing polymers have become increasingly attractive to polymer chemists because of their role as biomimetic analogues and their potential for commercial applications. Glycopolymers of different structures confer high hydrophilicity and water solubility and can therefore be used for specialised applications, such as artificial materials for a number of biological, pharmaceutical and biomedical uses. The synthesis and characterisation of a series of novel glycopolymer brushes, namely poly(2-(2-bromoisobutyryloxy ethyl methacrylate-g-poly(methyl 6-O-methacryloyl-α-D-glucoside (P(BIEM-g-P(6-O-MMAGIc, poly(2-(2-bromoisobutyryloxy ethyl methacrylate-co-methyl methacrylate-g-poly(methyl 6-O-methacryloyl-α-D-glucoside P(BIEM-co-MMA-g-P(6-O-MMAGIc, poly(2-(2-bromoisobutyryloxy ethyl methacrylate-b-methyl methacrylate-g-poly(methyl 6-O-methacryloyl-α-D-glucoside P(BIEM-b-MMA-g-P(6-O-MMAGIc and poly(4-vinylbenzyl chloride-alt-maleic anhydride-g-poly(methyl 6-O-methacryloyl-α-D-glucoside (P(Sd-alt-MAnh-g-P(6-O-MMAGIc are described in this paper. Reversible addition-fragmentation chain transfer (RAFT-mediated polymerisation was used to synthesise four well-defined atom transfer radical polymerisation (ATRP macroinitiators (the backbone of the glycopolymer brushes. These ATRP macroinitiators were subsequently used in the ‘grafting from’ approach (in which side chains are grown from the backbone to prepare high molar mass and low polydispersity index glycopolymer brushes with different grafting densities along the backbone. The number average molar mass of the glycopolymer brushes was determined using size exclusion chromatography with a multi-angle laser light

  18. Codex dietary fibre definition - Justification for inclusion of carbohydrates from 3 to 9 degrees of polymerisation.

    Science.gov (United States)

    de Menezes, Elizabete Wenzel; Giuntini, Eliana Bistriche; Dan, Milana Cara Tanasov; Sardá, Fabiana Andréa Hoffmann; Lajolo, Franco Maria

    2013-10-01

    The main controversy about the DF definition, adopted by the commission of Codex Alimentarius, refers to the inclusion of carbohydrates of 3-9 degrees of polymerisation (DP), decision which may be made individually by the authorities of each country. Due to the possibility of having two definitions and the negative impact it would cause over the harmonisation of nutritional information, a bibliographic review was carried, from 2009 to 2011, aiming to gather justifications for the inclusion of carbohydrates of 3-9 DP in the definition. The current review presents scientific bases that are directed to three topics: physiological aspects; repercussion over the analytical method; and impact on consumers and other users. The decision of including unavailable carbohydrates of 3-9 DP in the definition of DF may cause effective global harmonisation in the nutritional labelling, considering that the main goal is to help consumers choose healthy foods.

  19. Microfibrillated Lignocellulose Enables the Suspension-Polymerisation of Unsaturated Polyester Resin for Novel Composite Applications

    Directory of Open Access Journals (Sweden)

    Yutao Yan

    2016-07-01

    Full Text Available A new route towards embedding fibrillated cellulose in a non-polar thermoset matrix without any use of organic solvent or chemical surface modification is presented. It is shown that microfibrillated lignocellulose made from cellulose with high residual lignin content is capable of stabilising an emulsion of unsaturated polyester resin in water due to its amphiphilic surface-chemical character. Upon polymerisation of the resin, thermoset microspheres embedded in a microfibrillated cellulose network are formed. The porous network structure persists after conventional drying in an oven, yielding a mechanically stable porous material. In an application experiment, the porous material was milled into a fine powder and added to the polyester matrix of a glass fibre-reinforced composite. This resulted in a significant improvement in fracture toughness of the composite, whereas a reduction of bending strength and stiffness was observed in parallel.

  20. Solid-state polymerisation via [2+2] cycloaddition reaction involving coordination polymers.

    Science.gov (United States)

    Medishetty, Raghavender; Park, In-Hyeok; Lee, Shim Sung; Vittal, Jagadese J

    2016-03-14

    Highly crystalline metal ions containing organic polymers are potentially useful to manipulate the magnetic and optical properties to make advanced multifunctional materials. However, it is challenging to synthesise monocrystalline metal complexes of organic polymers and single-phase hybrid materials made up of both coordination and organic polymers by traditional solution crystallisation. This requires an entirely different approach in the solid-state by thermal or photo polymerisation of the ligands. Among the photochemical methods available, [2+2] cycloaddition reaction has been recently employed to generate cyclobutane based coordination polymers from the metal complexes. Cyclobutane polymers have also been integrated into coordination polymers in this way. Recent advancements in the construction of polymeric chains of cyclobutane rings through photo-dimerisation reaction in the monocrystalline solids containing metal complexes, coordination polymers and metal-organic framework structures are discussed here.

  1. An antibody that prevents serpin polymerisation acts by inducing a novel allosteric behaviour

    Science.gov (United States)

    Motamedi-Shad, Neda; Jagger, Alistair M.; Liedtke, Maximilian; Faull, Sarah V.; Nanda, Arjun Scott; Salvadori, Enrico; Wort, Joshua L.; Kay, Christopher W.M.; Heyer-Chauhan, Narinder; Miranda, Elena; Perez, Juan; Ordóñez, Adriana; Haq, Imran; Irving, James A.; Lomas, David A.

    2016-01-01

    Serpins are important regulators of proteolytic pathways with an antiprotease activity that involves a conformational transition from a metastable to a hyperstable state. Certain mutations permit the transition to occur in the absence of a protease; when associated with an intermolecular interaction, this yields linear polymers of hyperstable serpin molecules, which accumulate at the site of synthesis. This is the basis of many pathologies termed the serpinopathies. We have previously identified a monoclonal antibody (mAb4B12) that, in single-chain form, blocks α1-antitrypsin (α1-AT) polymerisation in cells. Here, we describe the structural basis for this activity. The mAb4B12 epitope was found to encompass residues Glu32, Glu39 and His43 on helix A and Leu306 on helix I. This is not a region typically associated with the serpin mechanism of conformational change, and correspondingly the epitope was present in all tested structural forms of the protein. Antibody binding rendered β-sheet A — on the opposite face of the molecule — more liable to adopt an ‘open’ state, mediated by changes distal to the breach region and proximal to helix F. The allosteric propagation of induced changes through the molecule was evidenced by an increased rate of peptide incorporation and destabilisation of a preformed serpin–enzyme complex following mAb4B12 binding. These data suggest that prematurely shifting the β-sheet A equilibrium towards the ‘open’ state out of sequence with other changes suppresses polymer formation. This work identifies a region potentially exploitable for a rational design of ligands that is able to dynamically influence α1-AT polymerisation. PMID:27407165

  2. New tetradentate N,N,N,N-chelating α-diimine ligands and their corresponding zinc and nickel complexes: synthesis, characterisation and testing as olefin polymerisation catalysts.

    Science.gov (United States)

    Li, Lidong; Gomes, Clara S B; Gomes, Pedro T; Duarte, M Teresa; Fan, Zhiqiang

    2011-04-07

    A series of zinc complexes of the general formula {[ZnCl(ArN=C(An)-C(An)=NAr)](+)}(2)[Zn(2)Cl(6)](2-) (where Ar = 2-(1-benzyl-1H-1,2,3-triazol-4-yl)phenyl 2a, 2-(1-(1-phenylethyl)-1H-1,2,3-triazol-4-yl)phenyl 2b, 2-(1-phenyl-1H-1,2,3-triazol-4-yl)phenyl 2c; An = acenaphthene backbone) were prepared by the condensation of acenaphthenequinone with the corresponding o-triazolyl-substituted anilines (2-(1-benzyl-1H-1,2,3-triazol-4-yl)aniline 1a, 2-(1-(1-phenylethyl)-1H-1,2,3-triazol-4-yl)aniline 1b, 2-(1-phenyl-1H-1,2,3-triazol-4-yl)aniline 1c) which were formed by the copper(I)-catalyzed Huisgen[3+2] dipolar cycloaddition between 2-ethynylaniline and the corresponding azides in high yields, using anhydrous ZnCl(2) as the metal template, in boiling glacial acetic acid. Zinc complexes of the type [ZnCl(ArN=C(An)-C(An)=NAr)](+)[ZnCl(3)(NCCH(3))](-) (4a-c) were synthesized by crystallisation of the corresponding complexes 2a-c in acetonitrile, at -20 °C. After removal of zinc dichloride from complexes 2a-c by the addition of potassium oxalate, in dichloromethane, the tetradentate N,N,N,N-chelating α-diimine ligands of the type ArN=C(An)-C(An)=NAr (5a-c) were obtained. The new ligand precursors and zinc complexes were characterised by elemental analysis, (1)H and (13)C{(1)H} NMR spectroscopy, two-dimensional NMR spectroscopy, and X-ray diffraction. Reaction of the ligand precursors 5a-c with [NiBr(2)(DME)], in dichloromethane, gave nickel complexes of the type [NiBr(2)(ArN=C(An)-C(An)=NAr)] (6a-c). The results of single crystal X-ray diffraction characterisation and magnetic susceptibility measurements demonstrated that nickel complexes 6a-c possess octahedral geometries around the nickel atoms with variable configurations, the Br atoms of which can be ionized when dissolved in methanol. In preliminary catalytic tests, complexes 6a-c revealed to be active as catalysts for the polymerisation of norbornene and styrene, when activated by cocatalyst MAO. The characterisation

  3. Development and characterisation of a molecularly imprinted polymer prepared by precipitation polymerisation for the determination of phenylurea herbicides.

    Science.gov (United States)

    Carabias-Martínez, Rita; Rodríguez-Gonzalo, Encarna; Herrero-Hernóndez, Eliseo; Díaz-García, Marta Elena

    2005-03-01

    New materials based on molecularly imprinted polymers (MIPs) have been developed for use as sorbents in solid phase extraction to preconcentrate some urea herbicides. In the preconcentration step, different molecularly imprinted polymers were tested using methacrylic acid (MAA) and 2-(trifluoromethyl)acrylic acid (TFMAA) as functional monomers, and linuron and isoproturon as templates. The best results were obtained when the polymer was synthesised using MAA with isoproturon as template. Another parameter evaluated was the way in which the polymer was obtained. We observed that the imprinted polymers obtained by precipitation displayed a greater capacity to retain the phenylureas. Studies conducted using scanning electron microscopy (SEM) revealed that the bulk polymerisation method is far from ideal owing to the random shape and size distribution of the particles obtained, whereas when polymerisation was carried out in precipitation microspheres were obtained. In order to confirm the interaction between the functional monomer and the template, 1H NMR (CD2Cl2) analyses were conducted. The results obtained suggest that the hydrogen and/or nitrogen of the amino group of the template would be involved in the formation of hydrogen bonds with the functional monomer. The imprinted polymer obtained by precipitation polymerisation with MAA as functional monomer and isoproturon as template can be applied to preconcentrate phenylureas when the sample is dissolved in toluene. The proposed methodology was employed to evaluate polymer selectivity towards humic acids and towards other herbicides.

  4. Nanocomposites with functionalised polysaccharide nanocrystals through aqueous free radical polymerisation promoted by ozonolysis.

    Science.gov (United States)

    Espino-Pérez, E; Gilbert, Robert G; Domenek, S; Brochier-Salon, M C; Belgacem, M N; Bras, J

    2016-01-01

    Cellulose nanocrystals (CNC) and starch nanocrystals (SNC) were grafted by ozone-initiated free-radical polymerisation of styrene in a heterogeneous medium. Surface functionalisation was confirmed by infrared spectroscopy, contact angle measurements, and thermogravimetric and elemental analysis. X-ray diffraction and scanning electron microscopy showed that there was no significant change in the morphology or crystallinity of the nanoparticles following ozonolysis. The grafting efficiency, quantified by (13)C NMR, was greater for SNC, with a styrene/anhydroglucose ratio of 1.56 compared to 0.25 for CNC. The thermal stability improved by 100°C. The contact angles were 97° and 78° following the SNC and CNC grafting, respectively, demonstrating the efficiency of the grafting in changing the surface properties even at low levels of surface substitution. The grafting increased the compatibility with the polylactide, and produced nanocomposites with improved water vapour barrier properties. Ozone-mediated grafting is thus a promising approach for surface functionalisation of polysaccharide nanocrystals.

  5. High-Order Volterra Model Predictive Control and Its Application to a Nonlinear Polymerisation Process

    Institute of Scientific and Technical Information of China (English)

    Yun Li; Hiroshi Kashiwagi

    2005-01-01

    Model Predictive Control (MPC) has recently found wide acceptance in the process industry, but existing design and implementation methods are restricted to linear process models. A chemical process, however, involves severe nonlinearity which cannot be ignored in practice. This paper aims to solve this nonlinear control problem by extending MPC to accommodate nonlinear models. It develops an analytical framework for nonlinear model predictive control (NMPC). It also offers a third-order Volterra series based nonparametric nonlinear modelling technique for NMPC design, which relieves practising engineers from the need for deriving a physical-principles based model first. An on-line realisation technique for implementing NMPC is then developed and applied to a Mitsubishi Chemicals polymerisation reaction process. Results show that this nonlinear MPC technique is feasible and very effective. It considerably outperforms linear and low-order Volterra model based methods. The advantages of the developed approach lie not only in control performance superior to existing NMPC methods, but also in eliminating the need for converting an analytical model and then convert it to a Volterra model obtainable only up to the second order.

  6. NDK Interacts with FtsZ and Converts GDP to GTP to Trigger FtsZ Polymerisation--A Novel Role for NDK.

    Directory of Open Access Journals (Sweden)

    Saurabh Mishra

    Full Text Available Nucleoside diphosphate kinase (NDK, conserved across bacteria to humans, synthesises NTP from NDP and ATP. The eukaryotic homologue, the NDPK, uses ATP to phosphorylate the tubulin-bound GDP to GTP for tubulin polymerisation. The bacterial cytokinetic protein FtsZ, which is the tubulin homologue, also uses GTP for polymerisation. Therefore, we examined whether NDK can interact with FtsZ to convert FtsZ-bound GDP and/or free GDP to GTP to trigger FtsZ polymerisation.Recombinant and native NDK and FtsZ proteins of Mycobacterium smegmatis and Mycobacterium tuberculosis were used as the experimental samples. FtsZ polymersation was monitored using 90° light scattering and FtsZ polymer pelleting assays. The γ32P-GTP synthesised by NDK from GDP and γ32P-ATP was detected using thin layer chromatography and quantitated using phosphorimager. The FtsZ bound 32P-GTP was quantitated using phosphorimager, after UV-crosslinking, followed by SDS-PAGE. The NDK-FtsZ interaction was determined using Ni2+-NTA-pulldown assay and co-immunoprecipitation of the recombinant and native proteins in vitro and ex vivo, respectively.NDK triggered instantaneous polymerisation of GDP-precharged recombinant FtsZ in the presence of ATP, similar to the polymerisation of recombinant FtsZ (not GDP-precharged upon the direct addition of GTP. Similarly, NDK triggered polymerisation of recombinant FtsZ (not GDP-precharged in the presence of free GDP and ATP as well. Mutant NDK, partially deficient in GTP synthesis from ATP and GDP, triggered low level of polymerisation of MsFtsZ, but not of MtFtsZ. As characteristic of NDK's NTP substrate non-specificity, it used CTP, TTP, and UTP also to convert GDP to GTP, to trigger FtsZ polymerisation. The NDK of one mycobacterial species could trigger the polymerisation of the FtsZ of another mycobacterial species. Both the recombinant and the native NDK and FtsZ showed interaction with each other in vitro and ex vivo, alluding to the

  7. NDK Interacts with FtsZ and Converts GDP to GTP to Trigger FtsZ Polymerisation--A Novel Role for NDK.

    Science.gov (United States)

    Mishra, Saurabh; Jakkala, Kishor; Srinivasan, Ramanujam; Arumugam, Muthu; Ranjeri, Raghavendra; Gupta, Prabuddha; Rajeswari, Haryadi; Ajitkumar, Parthasarathi

    2015-01-01

    Nucleoside diphosphate kinase (NDK), conserved across bacteria to humans, synthesises NTP from NDP and ATP. The eukaryotic homologue, the NDPK, uses ATP to phosphorylate the tubulin-bound GDP to GTP for tubulin polymerisation. The bacterial cytokinetic protein FtsZ, which is the tubulin homologue, also uses GTP for polymerisation. Therefore, we examined whether NDK can interact with FtsZ to convert FtsZ-bound GDP and/or free GDP to GTP to trigger FtsZ polymerisation. Recombinant and native NDK and FtsZ proteins of Mycobacterium smegmatis and Mycobacterium tuberculosis were used as the experimental samples. FtsZ polymersation was monitored using 90° light scattering and FtsZ polymer pelleting assays. The γ32P-GTP synthesised by NDK from GDP and γ32P-ATP was detected using thin layer chromatography and quantitated using phosphorimager. The FtsZ bound 32P-GTP was quantitated using phosphorimager, after UV-crosslinking, followed by SDS-PAGE. The NDK-FtsZ interaction was determined using Ni2+-NTA-pulldown assay and co-immunoprecipitation of the recombinant and native proteins in vitro and ex vivo, respectively. NDK triggered instantaneous polymerisation of GDP-precharged recombinant FtsZ in the presence of ATP, similar to the polymerisation of recombinant FtsZ (not GDP-precharged) upon the direct addition of GTP. Similarly, NDK triggered polymerisation of recombinant FtsZ (not GDP-precharged) in the presence of free GDP and ATP as well. Mutant NDK, partially deficient in GTP synthesis from ATP and GDP, triggered low level of polymerisation of MsFtsZ, but not of MtFtsZ. As characteristic of NDK's NTP substrate non-specificity, it used CTP, TTP, and UTP also to convert GDP to GTP, to trigger FtsZ polymerisation. The NDK of one mycobacterial species could trigger the polymerisation of the FtsZ of another mycobacterial species. Both the recombinant and the native NDK and FtsZ showed interaction with each other in vitro and ex vivo, alluding to the possibility of direct

  8. NDK Interacts with FtsZ and Converts GDP to GTP to Trigger FtsZ Polymerisation - A Novel Role for NDK

    Science.gov (United States)

    Mishra, Saurabh; Jakkala, Kishor; Srinivasan, Ramanujam; Arumugam, Muthu; Ranjeri, Raghavendra; Gupta, Prabuddha; Rajeswari, Haryadi; Ajitkumar, Parthasarathi

    2015-01-01

    Introduction Nucleoside diphosphate kinase (NDK), conserved across bacteria to humans, synthesises NTP from NDP and ATP. The eukaryotic homologue, the NDPK, uses ATP to phosphorylate the tubulin-bound GDP to GTP for tubulin polymerisation. The bacterial cytokinetic protein FtsZ, which is the tubulin homologue, also uses GTP for polymerisation. Therefore, we examined whether NDK can interact with FtsZ to convert FtsZ-bound GDP and/or free GDP to GTP to trigger FtsZ polymerisation. Methods Recombinant and native NDK and FtsZ proteins of Mycobacterium smegmatis and Mycobacterium tuberculosis were used as the experimental samples. FtsZ polymersation was monitored using 90° light scattering and FtsZ polymer pelleting assays. The γ32P-GTP synthesised by NDK from GDP and γ32P-ATP was detected using thin layer chromatography and quantitated using phosphorimager. The FtsZ bound 32P-GTP was quantitated using phosphorimager, after UV-crosslinking, followed by SDS-PAGE. The NDK-FtsZ interaction was determined using Ni2+-NTA-pulldown assay and co-immunoprecipitation of the recombinant and native proteins in vitro and ex vivo, respectively. Results NDK triggered instantaneous polymerisation of GDP-precharged recombinant FtsZ in the presence of ATP, similar to the polymerisation of recombinant FtsZ (not GDP-precharged) upon the direct addition of GTP. Similarly, NDK triggered polymerisation of recombinant FtsZ (not GDP-precharged) in the presence of free GDP and ATP as well. Mutant NDK, partially deficient in GTP synthesis from ATP and GDP, triggered low level of polymerisation of MsFtsZ, but not of MtFtsZ. As characteristic of NDK’s NTP substrate non-specificity, it used CTP, TTP, and UTP also to convert GDP to GTP, to trigger FtsZ polymerisation. The NDK of one mycobacterial species could trigger the polymerisation of the FtsZ of another mycobacterial species. Both the recombinant and the native NDK and FtsZ showed interaction with each other in vitro and ex vivo, alluding

  9. A comparative study of the physical properties of Sb{sub 2}S{sub 3} thin films treated with N{sub 2} AC plasma and thermal annealing in N{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Calixto-Rodriguez, M., E-mail: manuela@fis.unam.mx [Instituto de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, Apartado Postal 48-3, 62210, Cuernavaca, Morelos (Mexico); Martinez, H. [Instituto de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, Apartado Postal 48-3, 62210, Cuernavaca, Morelos (Mexico); Pena, Y. [Facultad de Ciencias Quimicas, Universidad Autonoma de Nuevo Leon, Pedro de Alba s/n, Cd. Universitaria, 66451, San Nicolas de los Garza, Nuevo Leon (Mexico); Flores, O. [Instituto de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, Apartado Postal 48-3, 62210, Cuernavaca, Morelos (Mexico); Esparza-Ponce, H.E. [Centro de Investigacion en Materiales Avanzados S.C., Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua, Chihuahua 31109 (Mexico); Sanchez-Juarez, A.; Campos-Alvarez, J. [Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, Privada Xochicalco s/n, Col. Centro, 62580, Temixco, Morelos (Mexico); Reyes, P. [Facultad de Ciencias, Departamento de Fisica, Universidad Autonoma del Estado de Mexico, Instituto Literario 100, Col. Centro, 50000, Toluca, Estado de Mexico (Mexico)

    2010-02-01

    As-deposited antimony sulfide thin films prepared by chemical bath deposition were treated with nitrogen AC plasma and thermal annealing in nitrogen atmosphere. The as-deposited, plasma treated, and thermally annealed antimony sulfide thin films have been characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy, scanning electron microscopy, atomic force microscopy, UV-vis spectroscopy, and electrical measurements. The results have shown that post-deposition treatments modify the crystalline structure, the morphology, and the optoelectronic properties of Sb{sub 2}S{sub 3} thin films. X-ray diffraction studies showed that the crystallinity of the films was improved in both cases. Atomic force microscopy studies showed that the change in the film morphology depends on the post-deposition treatment used. Optical emission spectroscopy (OES) analysis revealed the plasma etching on the surface of the film, this fact was corroborated by the energy dispersive X-ray spectroscopy analysis. The optical band gap of the films (E{sub g}) decreased after post-deposition treatments (from 2.36 to 1.75 eV) due to the improvement in the grain sizes. The electrical resistivity of the Sb{sub 2}S{sub 3} thin films decreased from 10{sup 8} to 10{sup 6} {Omega}-cm after plasma treatments.

  10. Advanced analytical methods for the structure elucidation of polystyrene-b-poly(n-butyl acrylate) block copolymers prepared by reverse iodine transfer polymerisation

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Trevor Gavin; Pfukwa, Helen; Pasch, Harald, E-mail: hpasch@sun.ac.za

    2015-09-10

    Reverse iodine transfer polymerisation (RITP) is a living radical polymerisation technique that has shown to be feasible in synthesising segmented styrene-acrylate copolymers. Polymers synthesised via RITP are typically only described regarding their bulk properties using nuclear magnetic resonance spectroscopy and size exclusion chromatography. To fully understand the complex composition of the polymerisation products and the RITP reaction mechanism, however, it is necessary to use a combination of advanced analytical methods. In the present RITP procedure, polystyrene was synthesised first and then used as a macroinitiator to synthesise polystyrene-block-poly(n-butyl acrylate) (PS-b-PBA) block copolymers. For the first time, these PS-b-PBA block copolymers were analysed by a combination of SEC, in situ{sup 1}H NMR and HPLC. {sup 1}H NMR was used to determine the copolymer composition and the end group functionality of the samples, while SEC and HPLC were used to confirm the formation of block copolymers. Detailed information on the living character of the RITP process was obtained. - Highlights: • Comprehensive analysis of novel block copolymers. • Polymers were prepared for the first time by reverse iodine transfer polymerisation. • Combination of SEC, NMR, kinetic NMR, HPLC and comprehensive 2D-HPLC was used. • Detailed information about complex molecular composition and polymerisation kinetics was obtained.

  11. AC 410 AC410 AC410 Unit 7 Homework Assignment

    OpenAIRE

    Laynebaril1

    2017-01-01

    AC 410 AC410 AC410 Unit 7 Homework Assignment Click Link Below To Buy: http://hwcampus.com/shop/ac410-unit-7-homework-assignment/    Questions Requiring Analysis 14-30   Early in your first audit of Star Corporation, you notice that sales and year-end inventory are almost unchanged from the prior year. However, cost of goods sold is less than in the preceding year, and accounts payable also are down substantially. Gross profit has increased, but this increase has not c...

  12. The human fungal pathogen Cryptococcus neoformans escapes macrophages by a phagosome emptying mechanism that is inhibited by Arp2/3 complex-mediated actin polymerisation.

    Directory of Open Access Journals (Sweden)

    Simon A Johnston

    Full Text Available The lysis of infected cells by disease-causing microorganisms is an efficient but risky strategy for disseminated infection, as it exposes the pathogen to the full repertoire of the host's immune system. Cryptococcus neoformans is a widespread fungal pathogen that causes a fatal meningitis in HIV and other immunocompromised patients. Following intracellular growth, cryptococci are able to escape their host cells by a non-lytic expulsive mechanism that may contribute to the invasion of the central nervous system. Non-lytic escape is also exhibited by some bacterial pathogens and is likely to facilitate long-term avoidance of the host immune system during latency. Here we show that phagosomes containing intracellular cryptococci undergo repeated cycles of actin polymerisation. These actin 'flashes' occur in both murine and human macrophages and are dependent on classical WASP-Arp2/3 complex mediated actin filament nucleation. Three dimensional confocal imaging time lapse revealed that such flashes are highly dynamic actin cages that form around the phagosome. Using fluorescent dextran as a phagosome membrane integrity probe, we find that the non-lytic expulsion of Cryptococcus occurs through fusion of the phagosome and plasma membranes and that, prior to expulsion, 95% of phagosomes become permeabilised, an event that is immediately followed by an actin flash. By using pharmacological agents to modulate both actin dynamics and upstream signalling events, we show that flash occurrence is inversely related to cryptococcal expulsion, suggesting that flashes may act to temporarily inhibit expulsion from infected phagocytes. In conclusion, our data reveal the existence of a novel actin-dependent process on phagosomes containing cryptococci that acts as a potential block to expulsion of Cryptococcus and may have significant implications for the dissemination of, and CNS invasion by, this organism.

  13. Plasma treatment advantages for textiles

    CERN Document Server

    Sparavigna, Amelia

    2008-01-01

    The textile industry is searching for innovative production techniques to improve the product quality, as well as society requires new finishing techniques working in environmental respect. Plasma surface treatments show distinct advantages, because they are able to modify the surface properties of inert materials, sometimes with environment friendly devices. For fabrics, cold plasma treatments require the development of reliable and large systems. Such systems are now existing and the use of plasma physics in industrial problems is rapidly increasing. On textile surfaces, three main effects can be obtained depending on the treatment conditions: the cleaning effect, the increase of microroughness (anti-pilling finishing of wool) and the production of radicals to obtain hydrophilic surfaces. Plasma polymerisation, that is the deposition of solid polymeric materials with desired properties on textile substrates, is under development. The advantage of such plasma treatments is that the modification turns out to ...

  14. Plasma and dietary carotenoids and vitamines A,C and E and the risk of colon and rectal cancer in the European prospective investigation into cancer and nutrition

    NARCIS (Netherlands)

    Leenders, M.; Leufkens, A.M.; Siersema, P.D.; Duijnhoven, van F.J.B.; Vrieling, A.; Hulshof, P.J.M.

    2014-01-01

    Carotenoids and vitamins A, C and E are possibly associated with a reduced colorectal cancer (CRC) risk through antioxidative properties. The association of prediagnostic plasma concentrations and dietary consumption of carotenoids and vitamins A, C and E with the risk of colon and rectal cancer was

  15. Characterization of Plasma-Polymerized 4-vinyl pyridine on Poly(Ethylene Terephthalate) film for anti-microbial properties

    DEFF Research Database (Denmark)

    Jiang, Juan; Winther-Jensen, Bjørn; Kjær, Erik Michael

    2005-01-01

    a linear relation between the polymerisation time and the thickness of the surface layer. To further strengthen the antibacterial function the poly-4-vinyl-pyridine surface layer can act as the base for including nano particles of silver precipitated from a salt solution due to ultraviolet radiation....... The mechanical strength of the bond between the substrate and the surface layer has been tested by several methods, and the antibacterial effect of the surface layer with and without silver nano particles has been estimated by measuring electrical resistance as a function of time. The bacteria investigated were......As an efficient way to create an anti-bacterial function on polymer surfaces, we have used plasma polymerisation to create a poly-4-vinyl-pyridine coating on the surface of a common polymer, PET, a polymerisation process that we have shown also works well on several other polymers. We have found...

  16. The Acid/Base Surface Characterization of Sandstone, Limestone and Marble and its Effect upon the Polymerisation of Tetraethoxysilane

    Directory of Open Access Journals (Sweden)

    Elizabeth S. Goins

    1994-11-01

    Full Text Available The conservation of historically important stone buildings and monuments is a complicated field that crosses the boundaries of several different disciplines; in particular chemistry, geology, biology and materials science. It is a fact of nature that materials decay, and the role of the conservator is to delay this process for as long as possible. One way of approaching the problem is to place the object in a controlled environment. This is, however, clearly impossible in the case of large objects, and is expensive for smaller objects. The problem has become of increasing concern as decay mechanisms seem to have accelerated along with urban activity - primarily industrialisation and the burning of fossil fuels. This study focuses on a preliminary investigation of the acid/base nature of some building stones in order to determine their effect upon the polymerisation processes of an alkoxysilane system.

  17. Peltier ac calorimeter

    OpenAIRE

    Jung, D. H.; Moon, I. K.; Jeong, Y. H.

    2001-01-01

    A new ac calorimeter, utilizing the Peltier effect of a thermocouple junction as an ac power source, is described. This Peltier ac calorimeter allows to measure the absolute value of heat capacity of small solid samples with sub-milligrams of mass. The calorimeter can also be used as a dynamic one with a dynamic range of several decades at low frequencies.

  18. ACAC Converters for UPS

    Directory of Open Access Journals (Sweden)

    Rusalin Lucian R. Păun

    2008-05-01

    Full Text Available This paper propose a new control technique forsingle – phase ACAC converters used for a on-line UPSwith a good dynamic response, a reduced-partscomponents, a good output characteristic, a good powerfactorcorrection(PFC. This converter no needs anisolation transformer. A power factor correction rectifierand an inverter with the proposed control scheme has beendesigned and simulated using Caspoc2007, validating theconcept.

  19. ACS: ALMA Common Software

    Science.gov (United States)

    Chiozzi, Gianluca; Šekoranja, Matej

    2013-02-01

    ALMA Common Software (ACS) provides a software infrastructure common to all ALMA partners and consists of a documented collection of common patterns and components which implement those patterns. The heart of ACS is based on a distributed Component-Container model, with ACS Components implemented as CORBA objects in any of the supported programming languages. ACS provides common CORBA-based services such as logging, error and alarm management, configuration database and lifecycle management. Although designed for ALMA, ACS can and is being used in other control systems and distributed software projects, since it implements proven design patterns using state of the art, reliable technology. It also allows, through the use of well-known standard constructs and components, that other team members whom are not authors of ACS easily understand the architecture of software modules, making maintenance affordable even on a very large project.

  20. Kinetic Studies of Atom Transfer Radical Polymerisations of Styrene and Chloromethylstyrene with Poly(3-hexyl thiophene Macroinitiator

    Directory of Open Access Journals (Sweden)

    Nattawoot Rattanathamwat

    2015-01-01

    Full Text Available Poly(3-hexyl thiophene-b-poly(styrene-co-chloromethylstyrene copolymers, to be used as a prepolymer for preparing donor-acceptor block copolymers for organic solar cells, have been synthesised by reacting P3HT macroinitiators with styrene and chloromethylstyrene via three types of atom transfer radical polymerisation (ATRP systems, which are (1 a normal ATRP, (2 activators generated by electron transfer (AGET, and (3 a simultaneous reverse and normal initiation (SR&NI. The kinetics of these ATRP systems were studied as a function of monomers to the macroinitiator molar ratio. It was found that all of the three types of ATRP systems led to first order kinetics with respect to monomers. The highest rate constant (k of 3.4 × 10−3 s−1 was obtained from the SR&NI ATRP system. The molecular weights of the product determined by the GPC were lower than were the theoretical values. The result was discussed in light of the chain transfer reaction to the poly(chloromethylstyrene repeating units. Morphology of the synthesized block copolymers, examined by an atomic force microscopy (AFM, were also compared and discussed.

  1. Synthesis and Properties of Star HPMA Copolymer Nanocarriers Synthesised by RAFT Polymerisation Designed for Selective Anticancer Drug Delivery and Imaging.

    Science.gov (United States)

    Chytil, Petr; Koziolová, Eva; Janoušková, Olga; Kostka, Libor; Ulbrich, Karel; Etrych, Tomáš

    2015-06-01

    High-molecular-weight star polymer drug nanocarriers intended for the treatment and/or visualisation of solid tumours were synthesised, and their physico-chemical and preliminary in vitro biological properties were determined. The water-soluble star polymer carriers were prepared by the grafting of poly(amido amine) (PAMAM) dendrimers by hetero-telechelic N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers, synthesised by the controlled radical Reversible Addition Fragmentation chain Transfer (RAFT) polymerisation. The well-defined star copolymers with Mw values ranging from 2 · 10(5) to 6 · 10(5) showing a low dispersity (approximately 1.2) were prepared in a high yield. A model anticancer drug, doxorubicin, was bound to the star polymer through a hydrazone bond, enabling the pH-controlled drug release in the target tumour tissue. The activated polymer arm ends of the star copolymer carrier enable a one-point attachment for the targeting ligands and/or a labelling moiety. In this study, the model TAMRA fluorescent dye was used to prove the feasibility of the polymer carrier visualisation by optical imaging in vitro. The tailor-made structure of the star polymer carriers should facilitate the synthesis of targeted polymer-drug conjugates, even polymer theranostics, for simultaneous tumour drug delivery and imaging.

  2. In-situ polymerisation of fully bioresorbable polycaprolactone/phosphate glass fibre composites: In vitro degradation and mechanical properties.

    Science.gov (United States)

    Chen, Menghao; Parsons, Andrew J; Felfel, Reda M; Rudd, Christopher D; Irvine, Derek J; Ahmed, Ifty

    2016-06-01

    Fully bioresorbable composites have been investigated in order to replace metal implant plates used for hard tissue repair. Retention of the composite mechanical properties within a physiological environment has been shown to be significantly affected due to loss of the integrity of the fibre/matrix interface. This study investigated phosphate based glass fibre (PGF) reinforced polycaprolactone (PCL) composites with 20%, 35% and 50% fibre volume fractions (Vf) manufactured via an in-situ polymerisation (ISP) process and a conventional laminate stacking (LS) followed by compression moulding. Reinforcing efficiency between the LS and ISP manufacturing process was compared, and the ISP composites revealed significant improvements in mechanical properties when compared to LS composites. The degradation profiles and mechanical properties were monitored in phosphate buffered saline (PBS) at 37°C for 28 days. ISP composites revealed significantly less media uptake and mass loss (pcomposites were substantially higher (pcomposites, which showed that the ISP manufacturing process provided a significantly enhanced reinforcement effect than the LS process. During the degradation study, statistically higher flexural property retention profiles were also seen for the ISP composites compared to LS composites. SEM micrographs of fracture surfaces for the LS composites revealed dry fibre bundles and poor fibre dispersion with polymer rich zones, which indicated poor interfacial bonding, distribution and adhesion. In contrast, evenly distributed fibres without dry fibre bundles or polymer rich zones, were clearly observed for the ISP composite samples, which showed that a superior fibre/matrix interface was achieved with highly improved adhesion.

  3. Interface modification and material synthesis of organic light-emitting diodes using plasma technology

    Science.gov (United States)

    Liang, Rongqing; Ou, Qiongrong; Yang, Cheng; He, Kongduo; Yang, Xilu; Zhong, Shaofeng; plasma application Team

    2015-09-01

    Organic light-emitting diodes (OLEDs), due to their unique properties of solution processability, compatibility with flexible substrates and with large-scale printing technology, attract huge interest in the field of lighting. The integration of plasma technology into OLEDs provides a new route to improve their performance. Here we demonstrate the modification of indium-tin-oxide (ITO) work function by plasma treatment, synthesis of thermally activated delayed fluorescence (TADF) materials using plasma grafting (polymerisation), and multi-layer solution processing achieved by plasma cross-linking.

  4. AcEST: DK950971 [AcEST

    Lifescience Database Archive (English)

    Full Text Available GN=... 37 0.66 tr|B1ACS4|B1ACS4_BALBO DMP1 (Fragment) OS=Balaenoptera borealis ... 37 0.66 tr|B1ACS3|B1ACS3...todon GN=DM... 37 1.1 tr|B1ACT4|B1ACT4_LISBO DMP1 (Fragment) OS=Lissodelphis borealis ... 37 1.1 tr|B1ACS2|B...SSSEEEIQSKNTEMESRRLTVDAY 160 >tr|B1ACS4|B1ACS4_BALBO DMP1 (Fragment) OS=Balaenoptera borealis GN=DMP1 PE=4 S

  5. Isolation of sequences flanking Ac insertion sites by Ac casting.

    Science.gov (United States)

    Wang, Dafang; Peterson, Thomas

    2013-01-01

    Localizing Ac insertions is a fundamental task in studying Ac-induced mutation and chromosomal rearrangements involving Ac elements. Researchers may sometimes be faced with the situation in which the sequence flanking one side of an Ac/Ds element is known, but the other flank is unknown. Or, a researcher may have a small sequence surrounding the Ac/Ds insertion site and needs to obtain additional flanking genomic sequences. One way to rapidly clone unknown Ac/Ds flanking sequences is via a PCR-based method termed Ac casting. This approach utilizes the somatic transposition activity of Ac during plant development, and provides an efficient means for short-range genome walking. Here we describe the principle of Ac casting, and show how it can be applied to isolate Ac macrotransposon insertion sites.

  6. AC-3 audio coder

    Science.gov (United States)

    Todd, Craig

    1995-12-01

    AC-3 is a system for coding up to 5.1 channels of audio into a low bit-rate data stream. High quality may be obtained with compression ratios approaching 12-1 for multichannel audio programs. The high compression ratio is achieved by methods which do not increase decoder memory, and thus cost. The methods employed include: the transmission of a high frequency resolution spectral envelope; and a novel forward/backward adaptive bit allocation algorithm. In order to satisfy practical requirements of an emissions coder, the AC-3 syntax includes a number of features useful to broadcasters and consumers. These features include: loudness uniformity between programs; dynamic range control; and broadcaster control of downmix coefficients. The AC-3 coder has been formally selected for inclusion of the U.S. HDTV broadcast standard, and has been informally selected for several additional applications.

  7. Tevatron AC dipole system

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, R.; Kopp, S.E.; /Texas U.; Jansson, A.; Syphers, M.J.; /Fermilab

    2007-06-01

    The AC dipole is an oscillating dipole magnet which can induce large amplitude oscillations without the emittance growth and decoherence. These properties make it a good tool to measure optics of a hadron synchrotron. The vertical AC dipole for the Tevatron is powered by an inexpensive high power audio amplifier since its operating frequency is approximately 20 kHz. The magnet is incorporated into a parallel resonant system to maximize the current. The use of a vertical pinger magnet which has been installed in the Tevatron made the cost relatively inexpensive. Recently, the initial system was upgraded with a more powerful amplifier and oscillation amplitudes up to 2-3{sigma} were achieved with the 980 GeV proton beam. This paper discusses details of the Tevatron AC dipole system and also shows its test results.

  8. Elicitation of Jerusalem artichoke (Helianthus tuberosus L.) cell suspension culture for enhancement of inulin production and altered degree of polymerisation.

    Science.gov (United States)

    Ma, Chunquan; Zhou, Dong; Wang, Haitao; Han, Dongming; Wang, Yang; Yan, Xiufeng

    2017-01-01

    Plant cell suspension cultures have emerged as a potential source of secondary metabolites for food additives and pharmaceuticals. In this study inulin accumulation and its degree of polymerisation (DP) in the treated cells in the same medium were investigated after treatment with six types of elicitors. An in vitro cell suspension culture of Jerusalem artichoke (Helianthus tuberosus L.) was optimised by adding an extra nitrogen source. According to the growth kinetics, a maximum biomass of 5.48 g L(-1) was obtained from the optimal cell suspension medium consisted of Murashige and Skoog basic medium (MS) + 1.0 mg L(-1) α-naphthalene acetic acid (NAA) + 1.0 mg L(-1) 6-benzylaminopurine (6-BA) + 0.5 mg L(-1) proline + 1.0 mg L(-1) glutamine. Methyl jasmonate (MeJA, 250 µmol L(-1) ) treatment for 15 days led to the highest levels of inulin (2955.27 ± 9.81 mg L(-1) compared to control of 1217.46 ± 0.26 mg L(-1) ). The elicited effect of five elicitors to the suspension cells of Jerusalem artichoke is as follows: AgNO3 (Ag, 10 µmol L(-1) ), salicylic acid (SA, 75 µmol L(-1) ), chitosan (KJT, 40 mg L(-1) ), Trichoderma viride (Tv, 90 mg L(-1) ), yeast extract (YE, 0.25 mg L(-1) ), and the corresponding content of inulin is increased by 2.05-, 1.93-, 1.76-, 1.44- and 1.18-fold compared to control, respectively. The obvious effect on the percentage of lower DP in inulin was observed in cells treated with 40 mg L(-1) KJT, 0.25 mg L(-1) YE and 10 µmol L(-1) Ag. Among the six types of elicitors, the descending order of inulin content is MeJA > Ag > SA > KJT > Tv > YE. For the purpose inulin with lower DP and its application to prebiotic food, three elicitors, including KJT, YE and Ag, can be used for the elicitation. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  9. AC/RF Superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Ciovati, Gianluigi [JLAB

    2015-02-01

    This contribution provides a brief introduction to AC/RF superconductivity, with an emphasis on application to accelerators. The topics covered include the surface impedance of normal conductors and superconductors, the residual resistance, the field dependence of the surface resistance, and the superheating field.

  10. Antioxidant capacity of plasma after red wine intake in Human

    Directory of Open Access Journals (Sweden)

    M. Gianmmanco

    2009-01-01

    Full Text Available Aim: Antioxidant effects after consumption of red wine have been investigated in several studies but results are contradictory and the difference in the plasma antioxidant capacity (AC after intake of red wine between women and men has never been studies. This work purpose is manifold: to ascertain whether red wine intake modifies the human plasma AC; to study the behaviour of plasma AC of women in comparison with men and finally to investigate on the plasma uric acid concentration and its relationships with the plasma AC after red wine intake.

  11. Compartmentalisation of cAMP-dependent signalling in blood platelets: The role of lipid rafts and actin polymerisation.

    Science.gov (United States)

    Raslan, Zaher; Naseem, Khalid M

    2015-01-01

    Prostacyclin (PGI2) inhibits blood platelets through the activation of membrane adenylyl cyclases (ACs) and cyclic adenosine 3',5'-monophosphate (cAMP)-mediated signalling. However, the molecular mechanism controlling cAMP signalling in blood platelet remains unclear, and in particular how individual isoforms of AC and protein kinase A (PKA) are coordinated to target distinct substrates in order to modulate platelet activation. In this study, we demonstrate that lipid rafts and the actin cytoskeleton may play a key role in regulating platelet responses to cAMP downstream of PGI2. Disruption of lipid rafts with methyl-beta-cyclodextrin (MβCD) increased platelet sensitivity to PGI2 and forskolin, a direct AC cyclase activator, resulting in greater inhibition of collagen-stimulated platelet aggregation. In contrast, platelet inhibition by the direct activator of PKA, 8-CPT-6-Phe-cAMP was unaffected by MβCD treatment. Consistent with the functional data, lipid raft disruption increased PGI2-stimulated cAMP formation and proximal PKA-mediated signalling events. Platelet inhibition, cAMP formation and phosphorylation of PKA substrates in response to PGI2 were also increased in the presence of cytochalasin D, indicating a role for actin cytoskeleton in signalling in response to PGI2. A potential role for lipid rafts in cAMP signalling is strengthened by our finding that a pool of ACV/VI and PKA was partitioned into lipid rafts. Our data demonstrate partial compartmentalisation of cAMP signalling machinery in platelets, where lipid rafts and the actin cytoskeleton regulate the inhibitory effects induced by PGI2. The increased platelet sensitivity to cAMP-elevating agents signalling upon raft and cytoskeleton disruption suggests that these compartments act to restrain basal cAMP signalling.

  12. High performance AC drives

    CERN Document Server

    Ahmad, Mukhtar

    2010-01-01

    This book presents a comprehensive view of high performance ac drives. It may be considered as both a text book for graduate students and as an up-to-date monograph. It may also be used by R & D professionals involved in the improvement of performance of drives in the industries. The book will also be beneficial to the researchers pursuing work on multiphase drives as well as sensorless and direct torque control of electric drives since up-to date references in these topics are provided. It will also provide few examples of modeling, analysis and control of electric drives using MATLAB/SIMULIN

  13. Modulation of release kinetics by plasma polymerization of ampicillin-loaded β-TCP ceramics

    Science.gov (United States)

    Labay, C.; Buxadera-Palomero, J.; Avilés, M.; Canal, C.; Ginebra, M. P.

    2016-08-01

    Beta-tricalcium phosphate (β-TCP) bioceramics are employed in bone repair surgery. Their local implantation in bone defects puts them in the limelight as potential materials for local drug delivery. However, obtaining suitable release patterns fitting the required therapeutics is a challenge. Here, plasma polymerization of ampicillin-loaded β-TCP is studied for the design of a novel antibiotic delivery system. Polyethylene glycol-like (PEG-like) coating of β-TCP by low pressure plasma polymerization was performed using diglyme as precursor, and nanometric PEG-like layers were obtained by simple and double plasma polymerization processes. A significant increase in hydrophobicity, and the presence of plasma polymer was visible on the surface by SEM and quantified by XPS. As a main consequence of the plasma polymerisation, the release kinetics were successfully modified, avoiding burst release, and slowing down the initial rate of release leading to a 4.5 h delay in reaching the same antibiotic release percentage, whilst conservation of the activity of the antibiotic was simultaneously maintained. Thus, plasma polymerisation on the surface of bioceramics may be a good strategy to design controlled drug delivery matrices for local bone therapies.

  14. AC Optimal Power Flow

    Energy Technology Data Exchange (ETDEWEB)

    2016-10-04

    In this work, we have implemented and developed the simulation software to implement the mathematical model of an AC Optimal Power Flow (OPF) problem. The objective function is to minimize the total cost of generation subject to constraints of node power balance (both real and reactive) and line power flow limits (MW, MVAr, and MVA). We have currently implemented the polar coordinate version of the problem. In the present work, we have used the optimization solver, Knitro (proprietary and not included in this software) to solve the problem and we have kept option for both the native numerical derivative evaluation (working satisfactorily now) as well as for analytical formulas corresponding to the derivatives being provided to Knitro (currently, in the debugging stage). Since the AC OPF is a highly non-convex optimization problem, we have also kept the option for a multistart solution. All of these can be decided by the user during run-time in an interactive manner. The software has been developed in C++ programming language, running with GCC compiler on a Linux machine. We have tested for satisfactory results against Matpower for the IEEE 14 bus system.

  15. A rapid quenched-flow device for the characterisation of the nascent polymerisation of ethylene under industrial conditions

    NARCIS (Netherlands)

    Di Martino, A.; Di Martino, Audrey; Broyer, Jean Pierre; Spitz, Roger; Weickert, G.; McKenna, Timothy F.

    2005-01-01

    A quenched-flow reactor is introduced as an effective means for the production of polyolefin particles with precisely controlled reaction times as low as 40 ms. The use of off-line scanning electron microscopy and induced-coupled plasma yields experimental data on the development of the kinetics and

  16. A Rapid Quenched-Flow Device for the Characterisation of the Nascent Polymerisation of Ethylene under Industrial Conditions

    NARCIS (Netherlands)

    Di Martino, Audrey; Broyer, Jean Pierre; Spitz, Roger; Weickert, Günter; McKenna, Timothy F.

    2005-01-01

    A quenched-flow reactor is introduced as an effective means for the production of polyolefin particles with precisely controlled reaction times as low as 40 ms. The use of off-line scanning electron microscopy and induced-coupled plasma yields experimental data on the development of the kinetics and

  17. Single-Phase Direct AC-AC Boost Converter

    Directory of Open Access Journals (Sweden)

    LUCANU, M.

    2014-08-01

    Full Text Available The paper presents a single-phase direct AC-AC boost converter. The circuit of the converter is simple and it has good performances, irrespective of the load nature. The adequate functioning and high performance of the circuit (the efficiency and waveform of the absorbed input current were tested both by simulation and experimentally.

  18. Cooling Floor AC Systems

    Science.gov (United States)

    Jun, Lu; Hao, Ding; Hong, Zhang; Ce, Gao Dian

    The present HVAC equipments for the residential buildings in the Hot-summer-and-Cold-winter climate region are still at a high energy consuming level. So that the high efficiency HVAC system is an urgently need for achieving the preset government energy saving goal. With its advantage of highly sanitary, highly comfortable and uniform of temperature field, the hot-water resource floor radiation heating system has been widely accepted. This paper has put forward a new way in air-conditioning, which combines the fresh-air supply unit and such floor radiation system for the dehumidification and cooling in summer or heating in winter. By analyze its advantages and limitations, we found that this so called Cooling/ Heating Floor AC System can improve the IAQ of residential building while keep high efficiency quality. We also recommend a methodology for the HVAC system designing, which will ensure the reduction of energy cost of users.

  19. On Improving Impedance Probe Plasma Potential Measurements

    Science.gov (United States)

    2014-02-21

    assumption of a collisionless, stationary Maxwellian plasma and are seen to work well in non -flowing plasmas of sufficient density. However, as plasma...collection area. For Maxwellian electrons, np = n exp(Vp-φp)/Te and so at low frequency from Eq. (1) above, the resistive component of the ac

  20. A search for natural bioactive compounds in Bolivia through a multidisciplinary approach. Part IV. Is a new haem polymerisation inhibition test pertinent for the detection of antimalarial natural products?

    Science.gov (United States)

    Baelmans, R; Deharo, E; Bourdy, G; Muñoz, V; Quenevo, C; Sauvain, M; Ginsburg, H

    2000-11-01

    The search for new antimalarial agents in plant crude extracts using traditional screening tests is time-consuming and expensive. New in vitro alternative techniques, based on specific metabolic or enzymatic process, have recently been developed to circumvent testing of antimalarial activity in parasite culture. The haem polymerisation inhibition test (HPIA) was proposed as a possible routine in vitro assay for the detection of antimalarial activity in natural products. A total of 178 plant extracts from the Pharmacopeia of the Bolivian ethnia Tacana, were screened for their ability to inhibit the polymerisation of haematin. Five extracts from Aloysia virgata (Ruíz & Pavón) A.L. Jussieu (Verbenaceae), Bixa orellana L. (Bixaceae), Caesalpinia pluviosa D.C. (Caesalpiniaceae), Mascagnia stannea (Griseb) Nied. (Malpighiaceae) and Trichilia pleenea (Adr. Jussieu) (Meliaceae) demonstrated more than 70% inhibition of haematin polymerisation at 2.5 mg/ml. The extracts were also tested for antimalarial activity in culture against F32 strain (chloroquine-sensitive) and D2 strain (chloroquine-resistant) of Plasmodium falciparum and in vivo against P. berghei. The extract from Caesalpinia pluviosa was the only one that showed activity in HPIA and in the classical test in culture. The accuracy and pertinence of HPIA, applied to natural products is discussed.

  1. ACS CCD Stability Monitor

    Science.gov (United States)

    Grogin, Norman

    2012-10-01

    A moderately crowded stellar field in the cluster 47 Tuc {6 arcmin West of the cluster core} is observed every four months with the WFC. The first visit exercises the full suite of broad and narrow band imaging filters and sub-array modes; following visits observe with only the six most popular Cycle 18 filters in full-frame mode. The positions and magnitudes of objects will be used to monitor local and large scale variations in the plate scale and the sensitivity of the detectors and to derive an independent measure of the detector CTE. One exposure in each sub-array mode with the WFC will allow us to verify that photometry obtained in full-frame and in sub-array modes are repeatable to better than 1%. This test is important for the ACS Photometric Cross-Calibration program, which uses sub-array exposures. This program may receive additional orbits to investigate ORIENT-dependent geometric distortion, which motivates the ORIENT and BETWEEN requirement on the first visit.

  2. AcEST: DK956383 [AcEST

    Lifescience Database Archive (English)

    Full Text Available TAC +HPGP Sbjct: 130 TP----GQAEEEKIEPLAPPVQKAVIDINQPQVCKNKGCGQTFKERDNHETACSHHPGPA 185 Query: 574 VF 579 VF S...AC +HPGP Sbjct: 130 TP----GQAEEEKIEPLAPPVQKAVIDINQPQVCKNKGCGQTFKERDNHETACSHHPGPA 185 Query: 574 VF 579 VF Sb

  3. Using AC Motors in Robotics

    Directory of Open Access Journals (Sweden)

    Hosein Marzi

    2008-11-01

    Full Text Available It has been proven that fuzzy controllers are capable of controlling non-linear systems where it is cumbersome to develop conventional controllers based on mathematical modeling. This paper describes designing fuzzy controllers for an AC motor run mechanism. It also compares performance of two controllers designed based on Mamdani and Takagi-Sugeno with the conventional control scheme in a short track length, following a high disturbance. Fine and rapid control of AC motors have been a challenge and the main obstacle in gaining popularity in use of AC motors in robots actuators. This chapter reviews how use of intelligent control scheme can help to solve this problem.

  4. Controlling the Plasma-Polymerization Process of N-Vinyl-2-pyrrolidone

    DEFF Research Database (Denmark)

    Norrman, Kion; Winther-Jensen, Bjørn

    2005-01-01

    N-vinyl-2-pyrrolidone was plasma-polymerized on glass substrates using a pulsed AC plasma. Pulsed AC plasma produces a chemical surface structure different from that produced by conventional RF plasma; this is ascribed to the different power regimes used. A high degree of control over the structure...... of the chemical surface was obtained using pulsed AC plasma, as shown by ToF-SIMS. It is demonstrated how the experimental conditions to some extent control the chemical structure of the plasma-polymerized film, e.g., film thickness, density of post-plasma-polymerized oligomeric chains, and the density of intact...

  5. Synthesis and spectroscopic and electrochemical characterisation of a conducting polythiophene bearing a chiral beta-substituent: polymerisation of (+)-4,4 bi.

    Science.gov (United States)

    Iarossi, D; Mucci, A; Parenti, F; Schenetti, L; Seeber, R; Zanardi, C; Forni, A; Tonelli, M

    2001-02-02

    A regioregular head-to-head/ tail-to-tail poly(beta,beta'-disubstituted bithiophene) P1 was synthesised by chemical and electrochemical polymerisation of 2,2'-bithiophene that bears (S)-2-methylbutylsulfanyl chains in the beta and beta'-positions. The polymer was characterised by GPC, NMR and UV/Vis spectroscopy, CD, AFM and by electrochemical and conductivity measurements. The CD spectra of P1 in solutions in which poor solvents are present show interesting features and allow the presence of different optically active species to be distinguished. Upon varying the casting conditions of P1, different relative amounts of grainy and homogeneous aggregated phases were observed in AFM micrographies of films and corresponding negative or positive first Cotton effects were found in the CD spectra. AFM, CD and UV/Vis characterisations were also performed on an electrogenerated optically active polymer PE1, in order to make a comparison with the chemically synthesised one. The interesting, small band gap of P1 allows for easy p- and n-electrochemical doping.

  6. Aislamiento acústico

    Directory of Open Access Journals (Sweden)

    Tobío, J. M.

    1970-07-01

    Full Text Available This is a very specific subject in the field of architectural acoustics, namely, insulation'. Emphasis is placed on the theoretical foundations of this phenomenon, and the most simple formula are developed to calculate easily the transmission losses of a material or the constructional insulating arrangements. The practical aspect of insulation can be considered by means of several graphs and charts, without the use of mathematics, and utilising common materials, that will not substantially increase the cost of the project. Finally this papers offers a critical discussion of building codes, and their reference to the acoustical insulation of dwellings, and data is included on the new regulations of the Madrid Municipality.Se trata un tema muy concreto de la Acústica Arquitectónica, el aislamiento, haciendo hincapié en los fundamentos teóricos del fenómeno y estableciendo las fórmulas más sencillas que permiten calcular fácilmente las pérdidas de transmisión de un material o disposición constructiva aislante. Varias gráficas y abacos permiten abordar, sin ningún tratamiento matemático, el problema práctico del aislamiento, aprovechando los materiales comunes y sin ocasionar gastos que graven sustancialmente el importe del proyecto. Por último, se hace un estudio crítico de las normas y su incidencia en los problemas del aislamiento de viviendas, incluyendo datos referentes a la nueva Ordenanza del Ayuntamiento de Madrid.

  7. Partial AC-coupling minigrids

    Energy Technology Data Exchange (ETDEWEB)

    Moix, Pierre-Olivier; Ruchet, Claude [Studer Innotec, Sion (Switzerland)

    2010-07-01

    Partial AC-coupling: - It is feasible to make AC-coupling of some compatible elements without V/f droops. Standard elements available on the market were tested. - Optimum design for efficiency is a share of the solar modules between DC-coupling with a solar charger and AC-coupling with a grid inverter according to the load profile. - Partial AC-coupling is better in term of robustness; it is more reliable to have at least a part of the solar production connected directly to DC, or even only DC coupling. The presented concepts are not only theoretical but were implemented and tested on real products available on the market. Many tests have been done to find out the limits and problems that can occur with the use of grid connected and stand alone inverter together. Many combinations were tested and it was found robust enough to be used in the field with the precautions mentioned about microcycling. (orig.)

  8. Total AC loss of YBCO coated conductor carrying AC transport current in AC transverse magnetic field with various orientations

    Energy Technology Data Exchange (ETDEWEB)

    Amemiya, Naoyuki [Faculty of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501 (Japan); Jiang, Zhenan [Faculty of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501 (Japan); Iijima, Yasuhiro [Materials Research Laboratory, Fujikura Ltd, 1-5-1 Kiba, Koto, Tokyo 135-8512 (Japan); Kakimoto, Kazuomi [Materials Research Laboratory, Fujikura Ltd, 1-5-1 Kiba, Koto, Tokyo 135-8512 (Japan); Saitoh, Takashi [Materials Research Laboratory, Fujikura Ltd, 1-5-1 Kiba, Koto, Tokyo 135-8512 (Japan)

    2004-08-01

    Using an electro-magnetic method, we measured the total AC loss of a YBCO coated conductor carrying an AC transport current in an AC transverse magnetic field with various orientations. We measured the magnetization loss (energy flow from the external magnetic field) and the transport loss (energy flow from the transport current circuit) independently during simultaneous application of an AC transverse magnetic field and AC transport current. Their sum gave us the total AC loss. The transport loss increases with increasing AC transverse magnetic field, and the magnetization loss increases with increasing AC transport current. The AC transverse magnetic field and the AC self magnetic field interact with each other at the conductor edges. This nonlinear interaction is a possible cause of the increase in AC loss. Due to the high aspect ratio of YBCO coated conductors, this increase in AC loss due to the interaction between the AC transverse and AC self magnetic fields is observed even when the transverse magnetic field is nearly parallel to the conductor wide-face. When the total AC losses for various transport currents and various field orientations are plotted against a transverse magnetic field component which is perpendicular to the conductor wide-face, the plots with different field angles but identical transport current all agree quite well with each other. The total AC loss is dominated by the self magnetic field and the perpendicular component of the transverse magnetic field, both of which mostly penetrate from the conductor edges.

  9. Distributed AC power flow method for AC and AC-DC hybrid ...

    African Journals Online (AJOL)

    DR OKE

    Present MGs incorporate AC and DC sources and loads along with storage and power ... Keywords: Microgrid (MG), Distributed Energy Resources (DER), Particle ... But in case of renewable based MGs, where small and intermittent sources ...

  10. Plasma Anemometer Measurements and Optimization

    Science.gov (United States)

    Marshall, Curtis; Matlis, Eric; Corke, Thomas; Gogineni, Sivaram

    2013-11-01

    Velocity measurements using a constant-current plasma anemometer were performed in a Mach 0.4 jet in order to further optimize the anemometer design. The plasma anemometer uses an AC glow discharge (plasma) formed in the air gap between two protruding low profile electrodes as the flow sensing element. The output from the anemometer is an amplitude modulated version of the AC voltage input that contains information about the mean fluctuating velocity components. Experiments were performed to investigate the effect of the electrode gap, AC current, and AC frequency on the mean and fluctuating velocity sensitivity and repeatability of the sensor. This involved mean velocity calibrations from 0 to 140 m/s and mean and fluctuating velocity profiles through the shear layer of the jet. Measurements with a constant temperature hot-wire anemometer were used for reference. The results showed an improvement in performance with increasing AC frequency that was attributed a more stable glow discharge. The agreement with the hot-wire were good, with the advantage of the plasma anemometer being its 100-times higher frequency response. Supported by Air Force SBIR Phase II FA8650-11-C-2199.

  11. Measurement of Current Profile in a Tokamak Through AC Modulation

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The plasma current is modulated with an alternating current (ac) component in a frequency range of 90 Hz~900 Hz in the plateau discharge phase in the CT-6B tokamak. A plasma electric conductivity profile in a form of (1 - r2/a2)α with a parameter α, which is fitted with the experimental data, can be determined. The effects of magnetic shear in a tokamak field configuration on the current penetration are taken into account in the numerical simulation. The measurement method and obtained results are discussed.

  12. The field of plasmas. L'univers des plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Bradu, P. (Direction des Recherches, Etudes et Techniques d' Armement (DRET), (France))

    1999-01-01

    Plasma is the fourth state of matter and it is the most spread at the scale of universe. Plasma is involved in natural phenomena such as Saint-Elmo's fires, aurora borealis or lightning discharges. Thanks to its particular properties plasma is used in many fields of technology. We find plasmas in light bulbs, television screens and in diverse industrial processes such as laser isotope separation, sterilization, surface coating, or waste treatment where a plasma torch is used to reduce waste into its elementary components trapped in the molten bulk. Spatial propulsion could soon benefit by the application of magnetohydrodynamics effects to plasmas. Thermonuclear reactors where fusion reactions take place in a very hot plasma could be the source of energy for the next century. This book deals with all the aspects of plasma in the technology of today. (A.C.) 21 refs.

  13. The field of plasmas; L`univers des plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Bradu, P. [Direction des Recherches, Etudes et Techniques d`Armement (DRET), (France)

    1999-12-01

    Plasma is the fourth state of matter and it is the most spread at the scale of universe. Plasma is involved in natural phenomena such as Saint-Elmo`s fires, aurora borealis or lightning discharges. Thanks to its particular properties plasma is used in many fields of technology. We find plasmas in light bulbs, television screens and in diverse industrial processes such as laser isotope separation, sterilization, surface coating, or waste treatment where a plasma torch is used to reduce waste into its elementary components trapped in the molten bulk. Spatial propulsion could soon benefit by the application of magnetohydrodynamics effects to plasmas. Thermonuclear reactors where fusion reactions take place in a very hot plasma could be the source of energy for the next century. This book deals with all the aspects of plasma in the technology of today. (A.C.) 21 refs.

  14. Hopping models and ac universality

    DEFF Research Database (Denmark)

    Dyre, Jeppe; Schrøder, Thomas

    2002-01-01

    Some general relations for hopping models are established. We proceed to discuss the universality of the ac conductivity which arises in the extreme disorder limit of the random barrier model. It is shown that the relevant dimension entering into the diffusion cluster approximation (DCA) is the h......) is the harmonic (fracton) dimension of the diffusion cluster. The temperature scaling of the dimensionless frequency entering into the DCA is discussed. Finally, some open problems regarding ac universality are listed.......Some general relations for hopping models are established. We proceed to discuss the universality of the ac conductivity which arises in the extreme disorder limit of the random barrier model. It is shown that the relevant dimension entering into the diffusion cluster approximation (DCA...

  15. AcEST: DK959177 [AcEST

    Lifescience Database Archive (English)

    Full Text Available _ARATH ATPase 1, plasma membrane-type OS=Arabidops... 141 3e-33 sp|Q08436|PMA3_NICPL Plasma membrane ATPase ... sp|Q9M2A0|PMA8_ARATH ATPase 8, plasma membrane-type OS=Arabidops... 138 2e-32 sp|P19456|PMA2_ARATH ATPase 2..., plasma membrane-type OS=Arabidops... 138 3e-32 sp|Q9LV11|PMA11_ARATH ATPase 11,... plasma membrane-type OS=Arabido... 137 7e-32 sp|P20431|PMA3_ARATH ATPase 3, plasma membrane-type OS=Arabidops...... 136 1e-31 sp|Q42556|PMA9_ARATH ATPase 9, plasma membrane-type OS=Arabidops... 135 1e-31 sp|Q9SU58|PMA4

  16. AcEST: DK961284 [AcEST

    Lifescience Database Archive (English)

    Full Text Available ase 1 OS=Nicotiana plumb... 344 3e-94 sp|Q9SU58|PMA4_ARATH ATPase 4, plasma membrane-type OS=Arabidops... 34...se 9, plasma membrane-type OS=Arabidops... 338 2e-92 sp|Q03194|PMA4_NICPL Plasma membrane ATPase 4 OS=Nicoti...stivum... 337 3e-92 sp|P20431|PMA3_ARATH ATPase 3, plasma membrane-type OS=Arabidops... 335 2e-91 sp|Q9SJB3|...PMA5_ARATH ATPase 5, plasma membrane-type OS=Arabidops... 334 3e-91 sp|P20649|PMA1_ARATH ATPase 1, plasma membrane-type OS=Arabidops...... 333 6e-91 sp|Q9M2A0|PMA8_ARATH ATPase 8, plasma membrane-type OS=Arabidops... 33

  17. AcEST: DK951424 [AcEST

    Lifescience Database Archive (English)

    Full Text Available S=Sola... 371 e-102 sp|Q9SU58|PMA4_ARATH ATPase 4, plasma membrane-type OS=Arabidops... 370 e-102 sp|Q08436|...1_SOLLC Plasma membrane ATPase 1 OS=Solanum lycoper... 363 e-100 sp|Q9SJB3|PMA5_ARATH ATPase 5, plasma membrane-type OS=Arabidops....e-99 sp|P20649|PMA1_ARATH ATPase 1, plasma membrane-type OS=Arabidops... 359 6e-9...3, plasma membrane-type OS=Arabidops... 356 7e-98 sp|P19456|PMA2_ARATH ATPase 2, plasma membrane-type OS=Arabidops....PMA6_ARATH ATPase 6, plasma membrane-type OS=Arabidops... 350 3e-96 sp|Q9M2A0|PMA

  18. AcEST: DK955959 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 8|PMA4_ARATH ATPase 4, plasma membrane-type OS=Arabidops... 356 5e-98 sp|P22180|P...MA1_SOLLC Plasma membrane ATPase 1 OS=Solanum lycoper... 353 4e-97 sp|Q9SJB3|PMA5_ARATH ATPase 5, plasma membrane-type OS=Arabidops....-95 sp|P20649|PMA1_ARATH ATPase 1, plasma membrane-type OS=Arabidops... 345 1e-94 sp|P20431|PMA3_ARATH ATPas...e 3, plasma membrane-type OS=Arabidops... 340 3e-93 sp|P19456|PMA2_ARATH ATPase 2, plasma membrane-type OS=Arabidops....6|PMA9_ARATH ATPase 9, plasma membrane-type OS=Arabidops... 335 9e-92 sp|Q9M2A0|P

  19. AcEST: DK961442 [AcEST

    Lifescience Database Archive (English)

    Full Text Available =Solanum lycoper... 362 e-99 sp|Q9SU58|PMA4_ARATH ATPase 4, plasma membrane-type OS=Arabidops... 360 3e-99 s...20649|PMA1_ARATH ATPase 1, plasma membrane-type OS=Arabidops... 340 4e-93 sp|P19456|PMA2_ARATH ATPase 2, pla...sma membrane-type OS=Arabidops... 336 7e-92 sp|P20431|PMA3_ARATH ATPase 3, plasma membrane-type OS=Arabidops....H ATPase 7, plasma membrane-type OS=Arabidops... 328 2e-89 sp|Q9SJB3|PMA5_ARATH ATPase 5, plasma membrane-type OS=Arabidops...... 327 3e-89 sp|Q9M2A0|PMA8_ARATH ATPase 8, plasma membrane-type OS=Arabidops... 326 6e-89 s

  20. AcEST: DK962689 [AcEST

    Lifescience Database Archive (English)

    Full Text Available ATPase 9, plasma membrane-type OS=Arabidops... 316 5e-86 sp|Q9SH76|PMA6_ARATH ATPase 6, plasma membrane-type OS=Arabidops...... 316 5e-86 sp|P19456|PMA2_ARATH ATPase 2, plasma membrane-type OS=Arabidops... 313 6e-85 sp...|P20649|PMA1_ARATH ATPase 1, plasma membrane-type OS=Arabidops... 310 5e-84 sp|Q9M2A0|PMA8_ARATH ATPase 8, p...lasma membrane-type OS=Arabidops... 308 1e-83 sp|P20431|PMA3_ARATH ATPase 3, plas...ma membrane-type OS=Arabidops... 307 3e-83 sp|Q9LV11|PMA11_ARATH ATPase 11, plasma membrane-type OS=Arabido.

  1. AcEST: DK954964 [AcEST

    Lifescience Database Archive (English)

    Full Text Available EAT Plasma membrane ATPase OS=Triticum aestivum... 171 2e-42 sp|P20649|PMA1_ARATH ATPase 1, plasma membrane-type OS=Arabidops.... sp|P19456|PMA2_ARATH ATPase 2, plasma membrane-type OS=Arabidops... 164 3e-40 sp|Q08436|PMA3_NICPL Plasma m...lasma membrane-type OS=Arabidops... 163 7e-40 sp|Q42556|PMA9_ARATH ATPase 9, plasma membrane-type OS=Arabidops...... 162 1e-39 sp|P20431|PMA3_ARATH ATPase 3, plasma membrane-type OS=Arabidops... 162 1e-39 sp|Q08435|PMA1...e-type OS=Arabido... 162 2e-39 sp|Q9SU58|PMA4_ARATH ATPase 4, plasma membrane-type OS=Arabidops... 159 8e-39

  2. AcEST: BP919129 [AcEST

    Lifescience Database Archive (English)

    Full Text Available sp|Q9SU58|PMA4_ARATH ATPase 4, plasma membrane-type OS=Arabidops... 314 2e-85 sp|P23980|PMA2_SOLLC Plasma m...Triticum aestivum... 297 2e-80 sp|Q42556|PMA9_ARATH ATPase 9, plasma membrane-type OS=Arabidops... 296 4e-80... sp|P20431|PMA3_ARATH ATPase 3, plasma membrane-type OS=Arabidops... 293 3e-79 sp|Q9SJB3|PMA5_ARATH ATPase 5..., plasma membrane-type OS=Arabidops... 293 3e-79 sp|P20649|PMA1_ARATH ATPase 1, p...lasma membrane-type OS=Arabidops... 292 6e-79 sp|P19456|PMA2_ARATH ATPase 2, plasma membrane-type OS=Arabidops.

  3. Speed Control of DC Motor using AC/AC/DC Converter Based on Intelligent Techniques

    Directory of Open Access Journals (Sweden)

    Rakan Kh Antar

    2013-05-01

    Full Text Available    This paper describes the application of ac/ac/dc and ac/dc converters to control the speed of a separately excited DC motor. Artificial neural network and PI controller are trained to select the desired values of firing angles for triggering thyristors of the ac/ac/dc and ac/dc bridge converters in order to control the speed of the dc motor at a desired value with constant and different load torques in order to obtain the best speed response. Simulation results show that the rising time for ac/dc and ac/ac/dc converters at 250rpm are reduced about 79% and 89% respectively, while delay time it reduced about 69% and 64% respectively. Therefore, speed response of the dc motor is more efficient for closed loop system compared with open loop also the response of ac/ac/dc converter is better than ac/dc converter.

  4. AC410 Unit 9 Assignment

    OpenAIRE

    Laynebaril1

    2017-01-01

     AC410 Unit 9 Assignment Click Link Below To Buy: http://hwcampus.com/shop/ac410-unit-9-assignment/   18–29. The CPA firm of Carson & Boggs LLP is performing an internal control audit in accordance with PCAOB Standard No. 5. The partner in charge of the engagement has asked you to explain the process of determining which controls to test. Describe the process, presenting each of the links in this process and a short summary of how the auditors approach each of them. v ...

  5. Electrothermal ac electro-osmosis

    Science.gov (United States)

    Gagnon, Zachary R.; Chang, Hsueh-Chia

    2009-01-01

    Two ac polarization mechanisms, charge accumulation due to electrode double layer charging and bulk permittivity/conductivity gradients generated by Joule heating, are combined in the double layer by introducing zwitterions to produce a new ac electrokinetic pump with the largest velocity (>1 mm/s) and flow penetration depth (100 μm) reported for low-conductivity fluids. The large fluid velocity is due to a quartic scaling with respect to voltage, as is true of electrothermal flow, but exhibits a clear maximum at a frequency corresponding to the electrode double layer inverse RC time.

  6. Nuclear structure of $^{231}$Ac

    CERN Document Server

    Boutami, R; Mach, H; Kurcewicz, W; Fraile, L M; Gulda, K; Aas, A J; García-Raffi, L M; Løvhøiden, G; Martínez, T; Rubio, B; Taín, J L; Tengblad, O

    2008-01-01

    The low-energy structure of 231Ac has been investigated by means of gamma ray spectroscopy following the beta-decay of 231Ra. Multipolarities of 28 transitions have been established by measuring conversion electrons with a mini-orange electron spectrometer. The decay scheme of 231Ra --> 231Ac has been constructed for the first time. The Advanced Time Delayed beta-gamma-gamma(t) method has been used to measure the half-lives of five levels. The moderately fast B(E1) transition rates derived suggest that the octupole effects, albeit weak, are still present in this exotic nucleus.

  7. AcEST: DK963222 [AcEST

    Lifescience Database Archive (English)

    Full Text Available sp|P81919|OR46A_DROME Odorant receptor 46a, isoform A OS=Drosoph... 32 2.8 sp|Q5MJ68|SPDYC_HUMAN Speed...FCFKA 181 CS +T + AV S L + +YV + AC Q FI C+ A Sbjct: 262 CSVLVLTANFYAIAVLSDERLELFKYVTYQACMLIQIFILCYYA 305 >sp|Q5MJ68|SPDYC_HUMAN Spee

  8. AcEST: DK953266 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 34 0.49 sp|A5VSF3|ACSA_BRUO2 Acetyl-coenzyme A synthetase OS=Brucella ov... 34 0.49 sp|Q8YJ48|ACSA_BRUME Ac... K++ + NK L+ R G WG GR++ Sbjct: 180 FVITADEGVRGGKPVALKENTDTAIDIAAKQYVMVNKVLVVRRTGGKVSWGRGRDL 235 >sp|A5VSF3|ACSA_BRUO2

  9. AcEST: BP918420 [AcEST

    Lifescience Database Archive (English)

    Full Text Available D 180 >sp|A8AC98|APGM_IGNH4 2,3-bisphosphoglycerate-independent phosphoglycerate mutase OS=Ignicoccus hosp...italis (strain KIN4/I / DSM 18386 / JCM 14125) GN=apgM PE=3 SV=1 Length = 416 Score

  10. AcEST: BP921446 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 34 2e-30 tr|A4VIU1|A4VIU1_PSEU5 Putative uncharacterized protein OS=Pseud... 129 1e-28 tr|Q11HF6|Q11HF6_MESSB...EHTHLMLDSKAGWVEPHIQAGDRCFAEYPDESLAQWHERLGL 159 >tr|Q11HF6|Q11HF6_MESSB Glutathione-dependent formaldehyde-ac

  11. AcEST: BP917259 [AcEST

    Lifescience Database Archive (English)

    Full Text Available Q96AC6|KIFC2_HUMAN Kinesin-like protein KIFC2 OS=Homo sapiens... 30 9.0 sp|O88737|BSN_MOUSE Protein bassoon ... WGQPG AAGS + PG Sbjct: 748 SSSPTEWVKWSWGQPG-------AAGSRAPPG 772 >sp|O88737|BSN_MOUSE Protein bassoon

  12. AcEST: DK947455 [AcEST

    Lifescience Database Archive (English)

    Full Text Available tative uncharacterized protein OS=Picea... 246 9e-64 tr|A8QIH7|A8QIH7_MORAL Chlor...DPTARSDNGSCEYEFKE 479 >tr|A8QIH7|A8QIH7_MORAL Chloroplast ribulose-1,5-bisphosphate carboxylase/oxygenase ac

  13. AcEST: DK943932 [AcEST

    Lifescience Database Archive (English)

    Full Text Available rella paten... 145 2e-33 tr|B6T2L2|B6T2L2_MAIZE Sedoheptulose-1,7-bisphosphatase ...EAL++SHVCK+AC Sbjct: 67 ATACVNTFGDEQLAVDMLADKLLFEALRHSHVCKYAC 103 >tr|B6T2L2|B6T2L2_MAIZE Sedoheptulose-1,7-

  14. AcEST: DK961189 [AcEST

    Lifescience Database Archive (English)

    Full Text Available OS=A... 127 7e-29 sp|Q94B08|GCP1_ARATH Germination-specific cysteine protease 1 OS... 125 2e-28 sp|P00785|AC...IRNSWGLNWGDSGYVKLQRNIDDPFGKCGIAMMPSYP 347 >sp|Q94B08|GCP1_ARATH Germination-specific cysteine protease 1 OS=

  15. AcEST: DK959208 [AcEST

    Lifescience Database Archive (English)

    Full Text Available Pase OS=Triticum aestivum... 195 2e-49 sp|P20649|PMA1_ARATH ATPase 1, plasma membrane-type OS=Arabidops... 1...ATPase 2, plasma membrane-type OS=Arabidops... 188 2e-47 sp|Q08436|PMA3_NICPL Pla...iana plumb... 186 8e-47 sp|Q42556|PMA9_ARATH ATPase 9, plasma membrane-type OS=Arabidops... 186 1e-46 sp|Q9M...2A0|PMA8_ARATH ATPase 8, plasma membrane-type OS=Arabidops... 186 1e-46 sp|P20431...|PMA3_ARATH ATPase 3, plasma membrane-type OS=Arabidops... 186 1e-46 sp|P22180|PMA1_SOLLC Plasma membrane AT

  16. AcEST: DK960225 [AcEST

    Lifescience Database Archive (English)

    Full Text Available . 122 1e-27 sp|Q9SU58|PMA4_ARATH ATPase 4, plasma membrane-type OS=Arabidops... 117 4e-26 sp|Q03194|PMA4_NIC...Plasma membrane ATPase OS=Triticum aestivum... 113 1e-24 sp|P19456|PMA2_ARATH ATPase 2, plasma membrane-type OS=Arabidops...... 112 1e-24 sp|P20649|PMA1_ARATH ATPase 1, plasma membrane-type OS=Arabidops... 111 4e-24 sp|...Q42556|PMA9_ARATH ATPase 9, plasma membrane-type OS=Arabidops... 108 2e-23 sp|Q7X...a membrane-type OS=Arabidops... 106 1e-22 sp|Q9SH76|PMA6_ARATH ATPase 6, plasma membrane-type OS=Arabidops..

  17. AcEST: DK952698 [AcEST

    Lifescience Database Archive (English)

    Full Text Available asma membrane ATPase 3 OS=Nicotiana plumb... 379 e-105 sp|P19456|PMA2_ARATH ATPase 2, plasma membrane-type OS=Arabidops....ma membrane-type OS=Arabidops... 375 e-103 sp|Q7XPY2|PMA1_ORYSJ Plasma membrane A...TPase OS=Oryza sativa subs... 372 e-102 sp|P20649|PMA1_ARATH ATPase 1, plasma membrane-type OS=Arabidops... ... ATPase 3, plasma membrane-type OS=Arabidops... 370 e-102 sp|Q42556|PMA9_ARATH AT...Pase 9, plasma membrane-type OS=Arabidops... 367 e-101 sp|P83970|PMA1_WHEAT Plasma membrane ATPase OS=Tritic

  18. ACS from development to operations

    Science.gov (United States)

    Caproni, Alessandro; Colomer, Pau; Jeram, Bogdan; Sommer, Heiko; Chiozzi, Gianluca; Mañas, Miguel M.

    2016-08-01

    The ALMA Common Software (ACS), provides the infrastructure of the distributed software system of ALMA and other projects. ACS, built on top of CORBA and Data Distribution Service (DDS) middleware, is based on a Component- Container paradigm and hides the complexity of the middleware allowing the developer to focus on domain specific issues. The transition of the ALMA observatory from construction to operations brings with it that ACS effort focuses primarily on scalability, stability and robustness rather than on new features. The transition came together with a shorter release cycle and a more extensive testing. For scalability, the most problematic area has been the CORBA notification service, used to implement the publisher subscriber pattern because of the asynchronous nature of the paradigm: a lot of effort has been spent to improve its stability and recovery from run time errors. The original bulk data mechanism, implemented using the CORBA Audio/Video Streaming Service, showed its limitations and has been replaced with a more performant and scalable DDS implementation. Operational needs showed soon the difference between releases cycles for Online software (i.e. used during observations) and Offline software, which requires much more frequent releases. This paper attempts to describe the impact the transition from construction to operations had on ACS, the solution adopted so far and a look into future evolution.

  19. AcEST: DK943965 [AcEST

    Lifescience Database Archive (English)

    Full Text Available FKBP-type OS=Cya... 55 2e-06 tr|B8EIG1|B8EIG1_METSI Peptidylprolyl isomerase FKBP-type OS=Met... 53 9e-06 t... type OS=Ac... 51 4e-05 tr|B8I9L2|B8I9L2_METNO Peptidylprolyl isomerase FKBP-type OS=Met.

  20. N-(2-Hydroxypropyl)methacrylamide-based polymer conjugates with pH-controlled activation of doxorubicin for cell-specific or passive tumour targeting. Synthesis by RAFT polymerisation and physicochemical characterisation.

    Science.gov (United States)

    Chytil, Petr; Etrych, Tomáš; Kříž, Jaroslav; Subr, Vladimír; Ulbrich, Karel

    2010-11-20

    Controlled radical reversible addition-fragmentation chain transfer (RAFT) polymerisation was used to prepare water-soluble polymer-drug carriers based on copolymers of N-(2-hydroxypropyl)methacrylamide (HPMA) with a hydrazide group-containing monomer, showing well-defined structure with narrow molecular weight distribution (approx. 1.1-1.2). The anticancer therapeutic doxorubicin was bound to the polymeric carrier by a hydrazone bond, enabling pH-controlled release under mildly acid conditions that mimics the environment in endosomes/lysosomes of tumour cells. RAFT polymerisation facilitated the synthesis of semitelechelic copolymers, which were used in the synthesis of monoclonal anti-CD20 antibody-polymer-drug conjugate designed for cell-specific tumour targeting. They were also used for producing a biodegradable high-molecular-weight graft polymer-drug conjugate that degrade in the presence of glutathione, which is designed for passive targeting to solid tumours. The conjugates exhibited well-defined structures with narrow molecular weight distributions of approx. 1.3 and pH-controlled drug release.

  1. AC dynamometer; Koryu dinamo meter

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-01-10

    Fuji Electric Co., Ltd., developed an AC dynamometer for testing automobiles, and the product was delivered to Hokkaido Automotive Engineering College via Safety Automobile Company. The device is used for testing 1,300cc-class automobiles. It is similar to the conventional type in that its force of reaction to an imposed load is measured by load cells. It is a variable speed motor driven by an inverter (FRENIC5000VG5), whose specifications and features are mentioned below. It is a totally-enclosed self-cooled oscillating AC dynamometer that outputs 75kW, revolves at 1500/2868rpm, and operates for 30min. Since it is rated for a short time operation, the external fan is dispensed with, and this reduces noise. A number of parts for the standard type (R90 series) are utilized for reduction in the cost, and the time required for its delivery was short. (NEDO)

  2. Performance of AC/graphite capacitors at high weight ratios of AC/graphite

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hongyu [IM and T Ltd., Advanced Research Center, Saga University, 1341 Yoga-machi, Saga 840-0047 (Japan); Yoshio, Masaki [Advanced Research Center, Department of Applied Chemistry, Saga University, 1341 Yoga-machi, Saga 840-0047 (Japan)

    2008-03-01

    The effect of negative to positive electrode materials' weight ratio on the electrochemical performance of both activated carbon (AC)/AC and AC/graphite capacitors has been investigated, especially in the terms of capacity and cycle-ability. The limited capacity charge mode has been proposed to improve the cycle performance of AC/graphite capacitors at high weight ratios of AC/graphite. (author)

  3. Electric field in an AC dielectric barrier discharge overlapped with a nanosecond pulse discharge

    Science.gov (United States)

    Goldberg, Benjamin M.; Shkurenkov, Ivan; Adamovich, Igor V.; Lempert, Walter R.

    2016-08-01

    The effect of ns discharge pulses on the AC barrier discharge in hydrogen in plane-to-plane geometry is studied using time-resolved measurements of the electric field in the plasma. The AC discharge was operated at a pressure of 300 Torr at frequencies of 500 and 1750 Hz, with ns pulses generated when the AC voltage was near zero. The electric field vector is measured by ps four-wave mixing technique, which generates coherent IR signal proportional to the square of electric field. Absolute calibration was done using an electrostatic (sub-breakdown) field applied to the discharge electrodes, when no plasma was generated. The results are compared with one-dimensional kinetic modeling of the AC discharge and the nanosecond pulse discharge, predicting behavior of both individual micro-discharges and their cumulative effect on the electric field distribution in the electrode gap, using stochastic averaging based on the experimental micro-discharge temporal probability distribution during the AC period. Time evolution of the electric field in the AC discharge without ns pulses, controlled by a superposition of random micro-discharges, exhibits a nearly ‘flat top’ distribution with the maximum near breakdown threshold, reproduced quite well by kinetic modeling. Adding ns pulse discharges on top of the AC voltage waveform changes the AC discharge behavior in a dramatic way, inducing transition from random micro-discharges to a more regular, near-1D discharge. In this case, reproducible volumetric AC breakdown is produced at a well-defined moment after each ns pulse discharge. During the reproducible AC breakdown, the electric field in the plasma exhibits a sudden drop, which coincides in time with a well-defined current pulse. This trend is also predicted by the kinetic model. Analysis of kinetic modeling predictions shows that this effect is caused by large-volume ionization and neutralization of surface charges on the dielectrics by ns discharge pulses. The present

  4. AcEST: DK943968 [AcEST

    Lifescience Database Archive (English)

    Full Text Available = +2 Query: 71 SSIRDLDNSRPRAIACSDNSGICVAVAYNHLANM------AVATFRDKPSVHQAGS---M 223 SS+ S P AC+ N+ VA HL+N+ A+ F...ives = 24/56 (42%) Frame = +2 Query: 107 AIACSDNSGICVAVAYNHLANMAVATFRDKPSVHQAGSMN...es = 83/195 (42%), Gaps = 1/195 (0%) Frame = +2 Query: 32 VLTACSSGVYFWDSSIRDLDNSRPRAIACSDNSGICVAVAYNHLANMAVA.../188 (41%), Gaps = 2/188 (1%) Frame = +2 Query: 32 VLTACSSGVYFWDSSIRDLDNSRPRAIACSDNSGICVAVAYN-HLANMAVATFRDKP... VLTACSSGVYFWDSSIRDLDNSRPRAIACSDNSGICVAVAYN-HLANMAVATFRDKPSVH 208 V++A S G WD D +RP + +N G+C+++A N +++ VA+FR

  5. AcEST: DK954735 [AcEST

    Lifescience Database Archive (English)

    Full Text Available AC ■■Homology search results ■■ - Swiss-Prot (release 56.9) Link to BlastX Result : Swiss-Prot sp_hit_id Q7TMD5 Definition sp|Q7TMD5...ng significant alignments: (bits) Value sp|Q7TMD5|ZC3HE_RAT Zinc finger CCCH domain-containing protein 1... ...tein pstB ... 30 5.8 sp|Q2S081|PSTB_SALRD Phosphate import ATP-binding protein pstB O... 30 7.6 >sp|Q7TMD5

  6. A plasma-arc pyrolysis system for hazardous waste treatment

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ A laboratory system for the treatment of medical and hazardous wastes via AC plasma-arc pyrolysis was recently built up by a research team led by Prof. SHENG Hongzhi at the CAS Institute of Mechanics (IMECH) in Beijing.

  7. Effect of the magnetic material on AC losses in HTS conductors in AC magnetic field carrying AC transport current

    Science.gov (United States)

    Wan, Xing-Xing; Huang, Chen-Guang; Yong, Hua-Dong; Zhou, You-He

    2015-11-01

    This paper presents an investigation on the AC losses in several typical superconducting composite conductors using the H-formulation model. A single superconducting strip with ferromagnetic substrate or cores and a stack of coated conductors with ferromagnetic substrates are studied. We consider all the coated conductors carrying AC transport currents and simultaneously exposed to perpendicular AC magnetic fields. The influences of the amplitude, frequency, phase difference and ferromagnetic materials on the AC losses are investigated. The results show that the magnetization losses of single strip and stacked strips have similar characteristics. The ferromagnetic substrate can increase the magnetization loss at low magnetic field, and decrease the loss at high magnetic field. The ferromagnetic substrate can obviously increase the transport loss in stacked strips. The trends of total AC losses of single strip and stacked strips are similar when they are carrying current or exposed to a perpendicular magnetic field. The effect of the frequency on the total AC losses of single strip is related to the amplitude of magnetic field. The AC losses decrease with increasing frequency in low magnetic field region while increase in high magnetic field region. As the phase difference changes, there is a periodic variation for the AC losses. Moreover, when the strip is under only the transport current and magnetic field, the ferromagnetic cores will increase the AC losses for large transport current or field.

  8. Universality of ac conduction in disordered solids

    DEFF Research Database (Denmark)

    Dyre, Jeppe; Schrøder, Thomas

    2000-01-01

    The striking similarity of ac conduction in quite different disordered solids is discussed in terms of experimental results, modeling, and computer simulations. After giving an overview of experiment, a macroscopic and a microscopic model are reviewed. For both models the normalized ac conductivity...... as a function of a suitably scaled frequency becomes independent of details of the disorder in the extreme disorder limit, i.e., when the local randomly varying mobilities cover many orders of magnitude. The two universal ac conductivities are similar, but not identical; both are examples of unusual non......-power-law universalities. It is argued that ac universality reflects an underlying percolation determining dc as well as ac conductivity in the extreme disorder limit. Three analytical approximations to the universal ac conductivities are presented and compared to computer simulations. Finally, model predictions...

  9. Control of grid interactive AC microgrids

    DEFF Research Database (Denmark)

    Wang, Xiongfei; Guerrero, Josep M.; Chen, Zhe

    2010-01-01

    and reliability, becomes an attractive candidate for the configuration of future electrical power system. This paper gives a brief review of grid interactive ac microgrid configurations. Control methods for power electronics interfaced DER units in grid interactive ac microgrids are discussed. In addition......, microgrid controls and power management strategies are presented. Future trends of microgrid are discussed pointing out how this concept can be a key to achieve a more intelligent and flexible AC grid....

  10. RHIC spin flipper AC dipole controller

    Energy Technology Data Exchange (ETDEWEB)

    Oddo, P.; Bai, M.; Dawson, C.; Gassner, D.; Harvey, M.; Hayes, T.; Mernick, K.; Minty, M.; Roser, T.; Severino, F.; Smith, K.

    2011-03-28

    The RHIC Spin Flipper's five high-Q AC dipoles which are driven by a swept frequency waveform require precise control of phase and amplitude during the sweep. This control is achieved using FPGA based feedback controllers. Multiple feedback loops are used to and dynamically tune the magnets. The current implementation and results will be presented. Work on a new spin flipper for RHIC (Relativistic Heavy Ion Collider) incorporating multiple dynamically tuned high-Q AC-dipoles has been developed for RHIC spin-physics experiments. A spin flipper is needed to cancel systematic errors by reversing the spin direction of the two colliding beams multiple times during a store. The spin flipper system consists of four DC-dipole magnets (spin rotators) and five AC-dipole magnets. Multiple AC-dipoles are needed to localize the driven coherent betatron oscillation inside the spin flipper. Operationally the AC-dipoles form two swept frequency bumps that minimize the effect of the AC-dipole dipoles outside of the spin flipper. Both AC bumps operate at the same frequency, but are phase shifted from each other. The AC-dipoles therefore require precise control over amplitude and phase making the implementation of the AC-dipole controller the central challenge.

  11. AcEST: DK959751 [AcEST

    Lifescience Database Archive (English)

    Full Text Available .. 86 1e-16 sp|A0FGR8|ESYT2_HUMAN Extended synaptotagmin-2 OS=Homo sapiens G... 72 3e-12 sp|Q6PFQ7|RASL2_MOU...SE Ras GTPase-activating protein 4 OS=Mus mus... 72 4e-12 sp|Q3TZZ7|ESYT2_MOUSE Extended...ivating-like protein 1 OS=Mus mu... 65 3e-10 sp|Q5M7N9|ESYT3_XENTR Extended synaptotagmin-3 OS=Xenopus tropi... 1 OS=Homo s... 61 6e-09 sp|Q8L7A4|AGD11_ARATH Probable ADP-ribosylation factor GTPase-ac... 61 6e-09 sp|Q7ZWU7|EST2B_XENLA Extended... synaptotagmin-2-B OS=Xenopus laev... 60 1e-08 sp|Q5FWL4|EST2A_XENLA Extended

  12. AcEST: BP920842 [AcEST

    Lifescience Database Archive (English)

    Full Text Available ta... 59 6e-09 sp|Q3TZZ7|ESYT2_MOUSE Extended synaptotagmin-2 OS=Mus musculus G... 59 7e-09 sp|Q9ZT47|PP16A_...CUCMA 16 kDa phloem protein 1 OS=Cucurbita maxim... 57 2e-08 sp|A0FGR8|ESYT2_HUMAN Extended synaptotagmin-2 ... domain-conta... 56 6e-08 sp|Q8L7A4|AGD11_ARATH Probable ADP-ribosylation factor GTPase-ac... 55 8e-08 sp|A0FGR9|ESYT3_HUMAN Extended... synaptotagmin-3 OS=Homo sapiens G... 55 1e-07 sp|Q5DTI8|ESYT3_MOUSE Extended synap...totagmin-3 OS=Mus musculus G... 54 2e-07 sp|Q5M7N9|ESYT3_XENTR Extended synaptota

  13. AcEST: DK956298 [AcEST

    Lifescience Database Archive (English)

    Full Text Available AIZE Glutamate dehydrogenase OS=Zea mays GN=GDH1... 370 e-102 sp|Q43314|DHE1_ARATH Glutamate dehydrogenase 1...HGK 202 >sp|P93541|DHE3_SOLLC Glutamate dehydrogenase OS=Solanum lycopersicum GN=GDH1 PE=2 SV=1 Length = 412...RG ++A EALL ++G+ Sbjct: 181 RDAATGRGALFATEALLNEHGK 202 >sp|Q43260|DHE3_MAIZE Glutamate dehydrogenase OS=Zea mays GN=GDH1...ATH Glutamate dehydrogenase 1 OS=Arabidopsis thaliana GN=GDH1 PE=1 SV=1 Length = 411 Score = 369 bits (946),...AC Glutamate dehydrogenase OS=Nicotiana taba... 376 e-103 tr|A7YVW3|A7YVW3_ACTCH GDH1 OS=Actinidia chinensis GN=GDH1

  14. Plasma Modeling of Electrosurgery

    Science.gov (United States)

    Jensen, Scott; Friedrichs, Daniel; Gilbert, James; Park, Wounjhang; Maksimovic, Dragan

    2014-10-01

    Electrosurgery is the use of high frequency alternating current (AC) to illicit a clinical response in tissue, such as cutting or cauterization. Power electronics converters have been demonstrated to generate the necessary output voltage and current for electrosurgery. The design goal of the converter is to regulate output power while supplying high frequency AC. The design is complicated by fast current and voltage transients that occur when the current travels through air in the form of an arc. To assist in designing a converter that maintains the desired output power during these transients, we have used the COMSOL Plasma Module to determine the output voltage and current characteristics during an arc. This plasma model, used in conjunction with linear circuit elements, allows the full electrosurgical system to be validated. Two models have been tested with the COMSOL Plasma Module. One is a four-species, four-reaction model based on the local field approximation technique. The second simulates the underlying air chemistry using 30 species, 151 chemical reactions, and a coupled electron energy distribution function. Experimental output voltage and current samples have been collected and compared to both models.

  15. Investigation of the Coupling Paths of a Galvanically Isolated AC/AC Converter

    NARCIS (Netherlands)

    Roc'h, Anne; Zhao, Dongsheng; Leferink, Frank; Polinder, Henk; Ferreira, Braham

    2007-01-01

    A galvanically isolated three-phase AC/AC converter with a high-frequency AC-link has been analyzed from an EMC point of view. This is a special configuration because of a large number of switches, a high frequency transformer, and a fourwire output. The essential coupling paths are identified. Corr

  16. AC polarographic determination of cloxacillin.

    Science.gov (United States)

    Núñez-Vergara, L J; Silva, M M; Squella, J A

    1982-11-01

    Hydrolysis of cloxacillin at pH 4.0 yields an electroactive product which can be determined by polarography. Depending on the concentration of cloxacillin, one of 2 peaks was obtained: The potential ac peaks for a 4.36 mM cloxacillin solution were peak I, -0.23 V and peak II, -0.13 V. For analytical purposes, the first peak was used. A linear relationship was established for levels of cloxacillin between 2.2 X 10(-5) and 2.2 X 10(-3)M. Average recovery was 98.8% (SD 1.8), indicating satisfactory accuracy for the method. Individual capsule and composite assays as well as interference tests are described.

  17. Flexible plasma linear antenna

    Science.gov (United States)

    Zhao, Jiansen; Wang, Shengzheng; Wu, Huafeng; Liu, Yue; Chang, Yongmeng; Chen, Xinqiang

    2017-02-01

    In this work, we introduce a type of plasma antenna that was fabricated using flexible materials and excited using a 5-20 kHz alternating current (ac) power supply. The results showed that the antenna characteristics, including the impedance, the reflection coefficient (S11), the radiation pattern, and the gain, can be controlled rapidly and easily by varying both the discharge parameters and the antenna shapes. The scope for reconfiguration is greatly enhanced when the antenna shape is changed from a monopole to a helix configuration. Additionally, the antenna polarization can also be adjusted by varying the antenna shapes.

  18. Ac-SDKP ameliorates the progression of lupus nephritis in MRL/lpr mice.

    Science.gov (United States)

    Tan, Hechang; Zhao, Jijun; Wang, Shuang; Zhang, Lili; Wang, Hongyue; Huang, Bin; Liang, Yingjie; Yu, Xueqing; Yang, Niansheng

    2012-12-01

    N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) is an endogenous tetrapeptide which can inhibit the differentiation, migration and activation of macrophages and suppress the proliferation of fibroblast. This study examined the effects of Ac-SDKP on the progression of lupus nephritis (LN). MRL/lpr mice received subcutaneous infusion of Ac-SDKP (1.0 mg kg(-1) d(-1)) or vehicle through implanted osmotic mini-pumps from 12 to 20 weeks until being euthanized. MRL/MpJ mice served as normal controls. The data indicative of renal inflammation and fibrosis were evaluated before and after treatment. Ac-SDKP-treated MRL/lpr mice showed reduced proteinuria and improved renal function compared with vehicle-treated controls. Ac-SDKP-treated mice demonstrated decreased inflammatory infiltrates of T cells and macrophages in the kidneys as compared to vehicle-treated animals. The treatment also inhibited the activation of NF-κB and production of TNF-α. Despite this, immune complex deposition and plasma anti-dsDNA levels were not statistically different between the two groups. In addition, the treatment inhibited renal expression of TGF-β1, α-SMA and fibronectin as well as the phosphorylation of Smad2/3. Ac-SDKP treatment ameliorated LN through exerting anti-inflammatory and anti-fibrotic effects on MRL/lpr mice, providing therapeutic potential for halting the progression of LN.

  19. Numerical Simulation of the Discharge Efficiency in Five-electrode AC PDP

    Institute of Scientific and Technical Information of China (English)

    何锋; 李永东; 刘纯亮; 孙鉴

    2004-01-01

    A new type of AC PDP (alternating current plasma display panel) cell with a fiveelectrode structure is developed to improve the luminous efficiency of AC PDP. The discharge efficiency of this new cell structure is investigated by a 2D fluid simulation. Continuity equations and flux density equations for charged particles and excited atoms, energy balance equation for electrons are included in the model. The discharge gas is He+5%Xe. The reactions of ionization,excitation, recombination, and radiation are taken into account. The vacuum ultraviolet radiation efficiency of the five-electrode cell structure is about 20% higher than that of a conventional three-electrode cell structure.

  20. AC-tabsmodeller for superledende kabelledere

    DEFF Research Database (Denmark)

    Østergaard, Jacob; Holm (fratrådt), Jesper; Understrup (fratrådt), Henriette

    1996-01-01

    I denne rapport opstilles tre modeller for beregning af AC-tab (vekselstrømstab) i superledende kabelledere. Beregning af tabenes størrelse er væsentlig i forbindelse med vurdering af superlederteknologiens anvendelighed til AC-applikationer. Viden om tabenes natur giver desuden et vigtigt...

  1. Versatile roles of V-ATPases accessory subunit Ac45 in osteoclast formation and function.

    Directory of Open Access Journals (Sweden)

    An Qin

    Full Text Available Vacuolar-type H(+-ATPases (V-ATPases are macromolecular proton pumps that acidify intracellular cargos and deliver protons across the plasma membrane of a variety of specialized cells, including bone-resorbing osteoclasts. Extracellular acidification is crucial for osteoclastic bone resorption, a process that initiates the dissolution of mineralized bone matrix. While the importance of V-ATPases in osteoclastic resorptive function is well-defined, whether V-ATPases facilitate additional aspects of osteoclast function and/or formation remains largely obscure. Here we report that the V-ATPase accessory subunit Ac45 participates in both osteoclast formation and function. Using a siRNA-based approach, we show that targeted suppression of Ac45 impairs intracellular acidification and endocytosis, both are prerequisite for osteoclastic bone resorptive function in vitro. Interestingly, we find that knockdown of Ac45 also attenuates osteoclastogenesis owing to a reduced fusion capacity of osteoclastic precursor cells. Finally, in an effort to gain more detailed insights into the functional role of Ac45 in osteoclasts, we attempted to generate osteoclast-specific Ac45 conditional knockout mice using a Cathepsin K-Cre-LoxP system. Surprisingly, however, insertion of the neomycin cassette in the Ac45-Flox(Neo mice resulted in marked disturbances in CNS development and ensuing embryonic lethality thus precluding functional assessment of Ac45 in osteoclasts and peripheral bone tissues. Based on these unexpected findings we propose that, in addition to its canonical function in V-ATPase-mediated acidification, Ac45 plays versatile roles during osteoclast formation and function.

  2. Influence of plasma discharge on the structure of polytetrafluoroethylene film and step coverage on polymer substrate

    Energy Technology Data Exchange (ETDEWEB)

    Grytsenko, K.P. [Institute of Semiconductor Physics, 45 Nauki pr., Kyiv, 03028 (Ukraine); Institute of Photonics, Laser and Plasma Technology, University of Applied Sciences Wildau, F.-Engels-Str. 63, 15745, Wildau (Germany)], E-mail: d_gryts@isp.kiev.ua; Lytvyn, P.M. [Institute of Semiconductor Physics, 45 Nauki pr., Kyiv, 03028 (Ukraine); Friedrich, J.; Schulze, R.D. [Federal Institute for Materials Research and Testing (BAM), Unter den Eichen 87, 12205 Berlin (Germany); Schrader, S. [Institute of Photonics, Laser and Plasma Technology, University of Applied Sciences Wildau, F.-Engels-Str. 63, 15745, Wildau (Germany)

    2007-09-15

    Polytetrafluoroethylene (PTFE) films have been deposited onto polycarbonate (PC) substrates from the products of PTFE evaporation, activated by a cloud of accelerated electrons. A 40.68 MHz glow discharge was used during the deposition process. The polymer films have been characterised by XPS, FTIR and AFM. The use of the low power plasma during film growth led to the formation of PTFE films with modified structure. Films are amorphous and contain more cross-links, but in general, the structure of their macromolecules is still linear. An increase of RF-power leads to the formation of films with large amount of double bonds and enhanced internal stresses. Deposition of PTFE on PC without plasma treatment led to the formation of PTFE clusters up to 50 nm in diameter. The RMS roughness of the films, deposited without plasma, was about 4 nm, while the films deposited with plasma treatment had a roughness of 1.5 nm. The use of plasma has an additional effect if a PTFE coating is deposited on the PC substrate with submicrometer-sized steps. Without plasma the steps retain a rectangular shape. Deposited with the RF-discharge the PTFE layers resemble plasma-polymerised films. Under certain conditions the deposited films can fill trenches in the substrate like a wetting liquid, while under other conditions they avoid trenches and grow in between them.

  3. AcEST: BP916793 [AcEST

    Lifescience Database Archive (English)

    Full Text Available SC complexes subunit ssr2 OS=S... 66 6e-14 sp|Q9XI07|SWI3C_ARATH SWI/SNF complex subunit SWI3C OS=Arabidops...... 65 1e-12 sp|Q8VY05|SWI3D_ARATH SWI/SNF complex subunit SWI3D OS=Arabidops... 66 2e-12 sp|P97496|SMRC1_MOU...2|SWI3B_ARATH SWI/SNF complex subunit SWI3B OS=Arabidops... 59 9e-09 sp|Q8W475|SWI3A_ARATH SWI/SNF complex s...ional adapter ADA2 OS=Oryza sati... 47 3e-05 sp|Q9ATB4|TAD2B_ARATH Transcriptional adapter ADA2b OS=Arabidops...... 45 2e-04 sp|Q9SFD5|TAD2A_ARATH Transcriptional adapter ADA2a OS=Arabidops... 44 3e-04 sp|Q5ZJF3|TAD2A_C

  4. Plasma turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Horton, W. [Univ. of Texas, Austin, TX (United States). Inst. for Fusion Studies; Hu, G. [Globalstar LP, San Jose, CA (United States)

    1998-07-01

    The origin of plasma turbulence from currents and spatial gradients in plasmas is described and shown to lead to the dominant transport mechanism in many plasma regimes. A wide variety of turbulent transport mechanism exists in plasmas. In this survey the authors summarize some of the universally observed plasma transport rates.

  5. Striations in Plasma Display Panel

    Institute of Scientific and Technical Information of China (English)

    OUYANG Ji-Ting; CAO Jing; MIAO Jin-Song

    2005-01-01

    @@ The phenomenon of striation has been investigated experimentally in a macroscopic ac-plasma display panel (PDP). The relationship between the characteristics of striation and the operation conditions including voltage, frequency, rib, and electrode configuration, etc is obtained experimentally. The origin of the striations is considered to be the ionization waves in the transient positive column near the dielectric surface in the anode area during the discharge, and the perturbation is caused by resonance kinetic effects in inert gas.

  6. Condensation production in comet tail plasma

    Directory of Open Access Journals (Sweden)

    S. V. Koshevaya

    2000-01-01

    Full Text Available Los solitones producen condensaciones en la cola del cometa, como resultado de su interacci on con el viento solar. Se obtienen las condiciones de excitaci on de las ondas ion ac usticas y polvo-ac usticas. La teor a presentada, trata sobre los solitones ion-ac usticos polvosos en este plasma magnetizado. Se demuestra que la longitud de Debye y el radio de cyclotr on de las part culas de polvo cargadas, de nen la dimensi on transversal de los solitones polvo-ac usticos. Para valores t picos de los par ametros, las dimensiones estimadas de los solitones son de varios Km, lo cual concuerda con los datos obtenidos de las observaciones.

  7. Plasma harmonics

    CERN Document Server

    Ganeev, Rashid A

    2014-01-01

    Preface; Why plasma harmonics? A very brief introduction Early stage of plasma harmonic studies - hopes and frustrations New developments in plasma harmonics studies: first successes Improvements of plasma harmonics; Theoretical basics of plasma harmonics; Basics of HHG Harmonic generation in fullerenes using few-cycle pulsesVarious approaches for description of observed peculiarities of resonant enhancement of a single harmonic in laser plasmaTwo-colour pump resonance-induced enhancement of odd and even harmonics from a tin plasmaCalculations of single harmonic generation from Mn plasma;Low-o

  8. Pulsed-DC DBD Plasma Actuators

    Science.gov (United States)

    Duong, Alan; McGowan, Ryan; Disser, Katherine; Corke, Thomas; Matlis, Eric

    2016-11-01

    A new powering system for dielectric barrier discharge (DBD) plasma actuators that utilizes a pulsed-DC waveform is presented. The plasma actuator arrangement is identical to most typical AC-DBD designs with staggered electrodes that are separated by a dielectric insulator. However instead of an AC voltage input to drive the actuator, the pulsed-DC utilizes a DC voltage source. The DC source is supplied to both electrodes, and remains constant in time for the exposed electrode. The DC source for the covered electrode is periodically grounded for very short instants and then allowed to rise to the source DC level. This process results in a plasma actuator body force that is significantly larger than that with an AC-DBD at the same voltages. The important characteristics used in optimizing the pulsed-DC plasma actuators are presented. Time-resolved velocity measurements near the actuator are further used to understand the underlying physics of its operation compared to the AC-DBD. Supported by NASA Glenn RC.

  9. Pregnancy-associated plasma protein-A and the vulnerable plaque

    DEFF Research Database (Denmark)

    Jespersen, Camilla H B; Vestergaard, Kirstine R; Schou, Morten

    2014-01-01

    For more than a decade, pregnancy-associated plasma protein-A (PAPP-A) has been examined for its relation to acute coronary syndrome (ACS) and the vulnerable plaque. This review summarizes the current knowledge of plasma PAPP-A in relation to nonpregnant individuals focusing on patients with ACS,......, discusses its use as a possible biomarker for diagnosis and prognosis in ACS, briefly describes the challenges in different assay technologies and describes the effect of heparin administration on PAPP-A concentrations in plasma....

  10. Adenylyl cyclase AC8 directly controls its micro-environment by recruiting the actin cytoskeleton in a cholesterol-rich milieu

    Science.gov (United States)

    Ayling, Laura J.; Briddon, Stephen J.; Halls, Michelle L.; Hammond, Gerald R. V.; Vaca, Luis; Pacheco, Jonathan; Hill, Stephen J.; Cooper, Dermot M. F.

    2012-01-01

    The central and pervasive influence of cAMP on cellular functions underscores the value of stringent control of the organization of adenylyl cyclases (ACs) in the plasma membrane. Biochemical data suggest that ACs reside in membrane rafts and could compartmentalize intermediary scaffolding proteins and associated regulatory elements. However, little is known about the organization or regulation of the dynamic behaviour of ACs in a cellular context. The present study examines these issues, using confocal image analysis of various AC8 constructs, combined with fluorescence recovery after photobleaching and fluorescence correlation spectroscopy. These studies reveal that AC8, through its N-terminus, enhances the cortical actin signal at the plasma membrane; an interaction that was confirmed by GST pull-down and immunoprecipitation experiments. AC8 also associates dynamically with lipid rafts; the direct association of AC8 with sterols was confirmed in Förster resonance energy transfer experiments. Disruption of the actin cytoskeleton and lipid rafts indicates that AC8 tracks along the cytoskeleton in a cholesterol-enriched domain, and the cAMP that it produces contributes to sculpting the actin cytoskeleton. Thus, an adenylyl cyclase is shown not just to act as a scaffold, but also to actively orchestrate its own micro-environment, by associating with the cytoskeleton and controlling the association by producing cAMP, to yield a highly organized signalling hub. PMID:22399809

  11. DC-Modulated PFC Buck-Type AC/AC Converter for Light Dimming

    Institute of Scientific and Technical Information of China (English)

    罗方林; 叶虹

    2007-01-01

    Dimmers are very widely applied in theatres, cinemas, dancing-parties, auditoriums and signal systems. They are usually supplied by single-stage AC/AC converters in the past with voltage regulation technique with the disadvantages of high total harmonic distortion, low power factor and poor power transfer efficiency. This paper introduces a novel method-DC-modulation that implements DC/DC conversion technology into AC/AC converters. The DC-modulated single-stage PFC AC/AC converters effectively improved the power factor up to 0.999 and the power transfer efficiency up to 97.8 %. The experimental results verified our design and calculation. This technique will be widely used in light dimming and other industrial applications.

  12. Cooperative Frequency Control for Autonomous AC Microgrids

    DEFF Research Database (Denmark)

    Shafiee, Qobad; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2015-01-01

    Distributed secondary control strategies have been recently studied for frequency regulation in droop-based AC Microgrids. Unlike centralized secondary control, the distributed one might fail to provide frequency synchronization and proportional active power sharing simultaneously, due to having...... not require measuring the system frequency as compared to the other presented methods. An ac Microgrid with four sources is used to verify the performance of the proposed control methodology....

  13. Guiding Principles in Selecting AC To DC Converters For Power Factor Corrections in AC Transmission System

    Directory of Open Access Journals (Sweden)

    Ibekwe B.E

    2014-10-01

    Full Text Available The ac to dc converters’ power factors correction in ac transmission system were investigated. The studies include: phase-controlled converter; pulse width modulated (PWM converter and ac input current shaped converter. Using Fourier series, power factors of these converters were calculated and simulated using MATLAB. The resulting curves are displayed in the hard copies for practical guides in the choice of converters; and comparatively, current shaped type is the best.

  14. The Effect of the Feedback Controller on Superconducting Tokamak AC Losses + AC-CRPP user manual

    Energy Technology Data Exchange (ETDEWEB)

    Schaerz, B.; Bruzzone, P.; Favez, J.Y.; Lister, J.B.; Zapretilina, E

    2001-11-01

    Superconducting coils in a Tokamak are subject to AC losses when the field transverse to the coil current varies. A simple model to evaluate the AC losses has been derived and benchmarked against a complete model used in the ITER design procedure. The influence of the feedback control strategy on the AC losses is examined using this model. An improved controller is proposed, based on this study. (author)

  15. 马士基将重组AC-2和AC-3航线

    Institute of Scientific and Technical Information of China (English)

    燕翔(整理)

    2014-01-01

    马士基航运将重组其远东-墨西哥-中美洲-南美洲西海岸航线“AC-2”线和“AC-3”线。“AC-2”线将延伸至华北和韩国,同时不再挂靠华南,在亚洲,该航线将加挂青岛和釜山,

  16. imulation Results of Single Stage AC- AC Converter for Induction Heating

    Directory of Open Access Journals (Sweden)

    S. ARUMUGAM

    2010-12-01

    Full Text Available This paper presents simulation of single stage Induction heating system with series Load Resonance. Low frequency AC is converted in to High Frequency Ac using newly developed ZVS-PWM high frequency inverter. This High Frequency is used for Induction Heating .Single stage AC-AC converter system is modeled and simulated using Matlab Simulink. The simulation results of ZVS-PWM high frequency system are presented. The effectiveness of this UFAC-to-HFAC direct power frequency converter using IGBTs for consumer high-frequency IH appliances is evaluated and proved on the basis of simulation results.

  17. Dusty plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Fortov, Vladimir E; Khrapak, Aleksei G; Molotkov, Vladimir I; Petrov, Oleg F [Institute for High Energy Densities, Associated Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation); Khrapak, Sergei A [Max-Planck-Institut fur Extraterrestrische Physik, Garching (Germany)

    2004-05-31

    The properties of dusty plasmas - low-temperature plasmas containing charged macroparticles - are considered. The most important elementary processes in dusty plasmas and the forces acting on dust particles are investigated. The results of experimental and theoretical investigations of different states of strongly nonideal dusty plasmas - crystal-like, liquid-like, gas-like - are summarized. Waves and oscillations in dusty plasmas, as well as their damping and instability mechanisms, are studied. Some results on dusty plasma investigated under microgravity conditions are presented. New directions of experimental research and potential applications of dusty plasmas are discussed. (reviews of topical problems)

  18. ISTTOK plasma control with the tomography diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, H.; Caralho, P.J.; Duarte, P.; Pereira, T.; Coelho, R.; Silva, C. [Association Euratom/IST, Institute of Plasmas and Nuclear Fusion, Technology Graduate Institute, P-1049-001 Lisbon (Portugal)

    2011-07-01

    A real-time plasma position control system is mandatory to achieve long duration (up to 250 ms), Alternating Current (AC) discharges on the ISTTOK tokamak. Such a system has been used for some time supported only on magnetic field diagnostic data. However, this system does not function accurately when the plasma current is low, rendering it inoperative during the plasma current reversal. A tomography diagnostic with 3 pinhole cameras and 8 silicone photodiode channels per camera was installed and customized to supply alternative plasma position to be used for plasma position control. As no filtering is applied, most of the radiation detected is in the visible/near-UV range. This system (i) executes a tomographic reconstruction, (ii) determines the average emissivity position from it, (iii) calculates the shift from the required position and (iv) supplies the vertical field power supply unit with the desired current value, all in less than 100 {mu}s. The horizontal magnetic field power supply unit is expected to be included in the system and will have no impact in the process time. This paper presents the tomography diagnostic architecture together with results of its scientific exploitation in ISTTOK AC discharges, where it has proven to be capable of supplying an accurate plasma position during the current reversal. The use of the tomography diagnostic for plasma position overcomes some limitations of the magnetic diagnostics, but poses challenges of its own such as blindness to plasma current direction. (authors)

  19. 78 FR 39345 - ACS Wireless, Inc.; Notice of Application

    Science.gov (United States)

    2013-07-01

    ... No. 812-14066] ACS Wireless, Inc.; Notice of Application AGENCY: Securities and Exchange Commission... (``Act''). Summary of Application: ACS Wireless, Inc. (``ACS Wireless'') seeks an order under section 3(b..., reinvesting, owning, holding or trading in securities. ACS Wireless is primarily engaged in providing...

  20. 21 CFR 886.1850 - AC-powered slitlamp biomicroscope.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered slitlamp biomicroscope. 886.1850... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1850 AC-powered slitlamp biomicroscope. (a) Identification. An AC-powered slitlamp biomicroscope is an AC-powered device that is...

  1. 21 CFR 886.4440 - AC-powered magnet.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered magnet. 886.4440 Section 886.4440 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4440 AC-powered magnet. (a) Identification. An AC-powered magnet is an AC-powered device that generates a magnetic field intended to find and...

  2. 21 CFR 888.1240 - AC-powered dynamometer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered dynamometer. 888.1240 Section 888.1240...) MEDICAL DEVICES ORTHOPEDIC DEVICES Diagnostic Devices § 888.1240 AC-powered dynamometer. (a) Identification. An AC-powered dynamometer is an AC-powered device intended for medical purposes to...

  3. 21 CFR 886.1630 - AC-powered photostimulator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered photostimulator. 886.1630 Section 886...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1630 AC-powered photostimulator. (a) Identification. An AC-powered photostimulator is an AC-powered device intended to provide light stimulus...

  4. Plasma carnitine concentrations after chronic alcohol intoxication.

    Science.gov (United States)

    Kępka, Alina; Waszkiewicz, Napoleon; Zalewska-Szajda, Beata; Chojnowska, Sylwia; Płudowski, Paweł; Konarzewska, Emilia; Szulc, Agata; Ladny, Jerzy Robert; Zwierz, Krzysztof; Szajda, Sławomir Dariusz

    2013-05-31

    Carnitine transports fatty acids from the cytoplasm to the mitochondrial matrix, where the fatty acids are oxidized. Chronic alcohol consumption reduces the concentration of carnitine and interferes with oxidative processes occurring in the cell. The assessment of carnitine concentrations in plasma of chronically intoxicated alcohol dependent persons in a 49-day abstinence period. The study included 31 patients (5 women and 27 men) aged from 26 to 60 years (44.6 ± 8.9) and 32 healthy subjects (15 women and 17 men) aged 22-60 years (39.8 ± 9.4). The patients' alcohol dependence ranged from 2 to 30 years (13.6 ± 7.5). Examined subjects consumed 75-700 g of ethanol/day (226.9 ± 151.5). Plasma concentrations of free and total carnitine were measured three times: at the first (T0), 30th (T30) and 49th (T49) day of hospital detoxification. Free (FC) and total (TC) carnitine were determined by the spectrophotometric method. Plasma acylcarnitine (AC) concentration was calculated from the difference between TC and FC; then the AC/FC ratio was calculated. To determine statistically significant differences for related variables, Student's t-test was used. At T0, alcoholics had significantly lower concentration of FC and TC (p < 0.05) in plasma, as compared to the control group. In comparison to controls, at T30, plasma TC and FC (p < 0.01) as well as AC (p < 0.001) were reduced. The lowest concentration of TC, FC and AC (p < 0.001)was found at T49. The ratio of AC/FC at T0 had a tendency to be higher in alcoholics than in the control group (p = 0.05), whereas at T49 it was significantly lower in alcoholics as compared to the control subjects (p < 0.05). Chronic alcohol intoxication causes a plasma deficiency of carnitine. Forty-nine days of abstinence showed a significant decrease in the concentration of TC, FC and AC. Further research is necessary to clarify whether a low level of plasma carnitine after chronic alcohol intoxication is caused by the uptake of blood

  5. AC Electrokinetics of Physiological Fluids for Biomedical Applications.

    Science.gov (United States)

    Lu, Yi; Liu, Tingting; Lamanda, Ariana C; Sin, Mandy L Y; Gau, Vincent; Liao, Joseph C; Wong, Pak Kin

    2015-12-01

    Alternating current (AC) electrokinetics is a collection of processes for manipulating bulk fluid mass and embedded objects with AC electric fields. The ability of AC electrokinetics to implement the major microfluidic operations, such as pumping, mixing, concentration, and separation, makes it possible to develop integrated systems for clinical diagnostics in nontraditional health care settings. The high conductivity of physiological fluids presents new challenges and opportunities for AC electrokinetics-based diagnostic systems. In this review, AC electrokinetic phenomena in conductive physiological fluids are described followed by a review of the basic microfluidic operations and the recent biomedical applications of AC electrokinetics. The future prospects of AC electrokinetics for clinical diagnostics are presented.

  6. Assembly of 1D, 2D and 3D lanthanum(iii) coordination polymers with perchlorinated benzenedicarboxylates: positional isomeric effect, structural transformation and ring-opening polymerisation of glycolide.

    Science.gov (United States)

    Chen, Sheng-Chun; Dai, An-Qi; Huang, Kun-Lin; Zhang, Zhi-Hui; Cui, Ai-Jun; He, Ming-Yang; Chen, Qun

    2016-02-28

    Utilizing a series of positional isomers of tetrachlorinated benzenedicarboxylic acid ligands, seven La(iii)-based coordination polymers were solvothermally synthesized and structurally characterized. Their structural dimensionalities varying from 1D double chains, to the 2D 3,4,5-connected network, to 3D 6-connected pcu topological nets are only governed by the positions of carboxyl groups on the tetrachlorinated benzene ring. A comprehensive analysis and comparison reveals that the size of the carbonyl solvent molecules (DMF, DEF, DMA, and NMP) can affect the coordination geometries around the La(iii) ions, the coordination modes of carboxylate groups, the packing arrangements, and the void volumes of the overall crystal lattices. One as-synthesized framework further shows an unprecedented structural transformation from a 3D 6-connected network to a 3D 4,5-connected net through the dissolution and reformation pathway in water, suggesting that these easily hydrolyzed lanthanide complexes may serve as precursors to produce new high-dimensional frameworks. The bulk solvent-free melt polymerisation of glycolide utilizing these La(iii) complexes as initiators has been reported herein for the first time. All complexes were found to promote the polymerization of glycolide over a temperature range of 200 to 220 °C, producing poly(glycolic acid) (PGA) with a molecular weight up to 93,280. Under the same experimental conditions, the different catalytic activities for these complexes may result from their structural discrepancy.

  7. The Sloan Lens ACS Survey. V. The full ACS strong-lens sample

    NARCIS (Netherlands)

    Bolton, Adam S.; Burles, Scott; Koopmans, Leon V. E.; Treu, Tommaso; Gavazzi, Raphael; Moustakas, Leonidas A.; Wayth, Randall; Schlegel, David J.

    2008-01-01

    We present the definitive data for the full sample of 131 strong gravitational lens candidates observed with the Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope by the Sloan Lens ACS (SLACS) Survey. All targets were selected for higher redshift emission lines and lower redshift

  8. The Sloan Lens ACS Survey. V. The full ACS strong-lens sample

    NARCIS (Netherlands)

    Bolton, Adam S.; Burles, Scott; Koopmans, Leon V. E.; Treu, Tommaso; Gavazzi, Raphael; Moustakas, Leonidas A.; Wayth, Randall; Schlegel, David J.

    2008-01-01

    We present the definitive data for the full sample of 131 strong gravitational lens candidates observed with the Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope by the Sloan Lens ACS (SLACS) Survey. All targets were selected for higher redshift emission lines and lower redshift c

  9. Approaches to building single-stage AC/AC conversion switch-mode audio power amplifiers

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2004-01-01

    This paper discusses the possible topologies and promising approaches towards direct single-phase AC-AC conversion of the mains voltage for audio applications. When compared to standard Class-D switching audio power amplifiers with a separate power supply, it is expected that direct conversion...

  10. Plasma waves

    CERN Document Server

    Swanson, DG

    1989-01-01

    Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th

  11. Plasma astrophysics

    CERN Document Server

    Kaplan, S A; ter Haar, D

    2013-01-01

    Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

  12. Pilot Experience with an External Quality Assurance Scheme for Acylcarnitines in Plasma/Serum

    NARCIS (Netherlands)

    Sala, P Ruiz; Ruijter, G; Acquaviva, C; Chabli, A; de Sain-van der Velden, M G M; Garcia-Villoria, J; Heiner-Fokkema, M R; Jeannesson-Thivisol, E; Leckstrom, K; Franzson, L; Lynes, G; Olesen, J; Onkenhout, W; Petrou, P; Drousiotou, A; Ribes, A; Vianey-Saban, C; Merinero, B

    2016-01-01

    The analysis of acylcarnitines (AC) in plasma/serum is established as a useful test for the biochemical diagnosis and the monitoring of treatment of organic acidurias and fatty acid oxidation defects. External quality assurance (EQA) for qualitative and quantitative AC is offered by ERNDIM and CDC i

  13. Pilot Experience with an External Quality Assurance Scheme for Acylcarnitines in Plasma/Serum

    NARCIS (Netherlands)

    Sala, P Ruiz; Ruijter, G; Acquaviva, C; Chabli, A; de Sain-van der Velden, M G M; Garcia-Villoria, J; Heiner-Fokkema, M R; Jeannesson-Thivisol, E; Leckstrom, K; Franzson, L; Lynes, G; Olesen, J; Onkenhout, W; Petrou, P; Drousiotou, A; Ribes, A; Vianey-Saban, C; Merinero, B

    2016-01-01

    The analysis of acylcarnitines (AC) in plasma/serum is established as a useful test for the biochemical diagnosis and the monitoring of treatment of organic acidurias and fatty acid oxidation defects. External quality assurance (EQA) for qualitative and quantitative AC is offered by ERNDIM and CDC

  14. Cyclotron and linac production of Ac-225.

    Science.gov (United States)

    Melville, Graeme; Allen, Barry J

    2009-04-01

    Radium needles that were once implanted into tumours as a cancer treatment are now obsolete and constitute a radioactive waste problem, as their half-life is 1600 years. The reduction of radium by photonuclear transmutation by bombarding Ra-226 with high-energy photons from a medical linear accelerator (linac) has been investigated. A linac dose of 2800 Gy produced about 2.4 MBq (64 microCi) of Ra-225, which decays to Ac-225 and can then be used for 'Targeted Alpha Therapy' (TAT) of cancer. This result, while consistent with theoretical calculations, is far too low to be of practical use unless much larger quantities of radium are irradiated. The increasing application of Ac-225 for cancer therapy indicates the potential need for its increased production and availability. This paper investigates the possibility of producing of Ac-225 in commercial quantities, which could potentially reduce obsolete radioactive material and displace the need for expensive importation of Ac-225 from the USA and Russia in the years ahead. Scaled up production of Ac-225 could theoretically be achieved by the use of a high current cyclotron or linac. Production specifications are determined for a linac in terms of current, pulse length and frequency, as well as an examination of other factors such as radiation issues and radionuclei separation. Yields are compared with those calculated for the Australian National Cyclotron in Sydney.

  15. AC/DC and DC/AC Converty Circuits in Power Supply Equipment%电源设备中AC/DC和DC/AC变换电路

    Institute of Scientific and Technical Information of China (English)

    杨碧石

    2001-01-01

    电源设备中根据电路变换功能来看,可分为四种类型:AC/DC、DC/AC、DC/DC、AC/AC,本文对AC/DC、DC/AC这两种变换的工作原理进行分析阐述并讨论每种电路的应用领域.

  16. Identification of Domains within the V-ATPase Accessory Subunit Ac45 Involved in V-ATPase Transport and Ca2+-dependent Exocytosis

    Science.gov (United States)

    Jansen, Eric J. R.; van Bakel, Nick. H. M.; Loohuis, Nikkie F. M. Olde; Hafmans, Theo G. M.; Arentsen, Tim; Coenen, Anthon J. M.; Scheenen, Wim J. J. M.; Martens, Gerard J. M.

    2012-01-01

    The vacuolar (H+)-ATPase (V-ATPase) is crucial for maintenance of the acidic microenvironment in intracellular organelles, whereas its membrane-bound V0-sector is involved in Ca2+-dependent membrane fusion. In the secretory pathway, the V-ATPase is regulated by its type I transmembrane and V0-associated accessory subunit Ac45. To execute its function, the intact-Ac45 protein is proteolytically processed to cleaved-Ac45 thereby releasing its N-terminal domain. Here, we searched for the functional domains within Ac45 by analyzing a set of deletion mutants close to the in vivo situation, namely in transgenic Xenopus intermediate pituitary melanotrope cells. Intact-Ac45 was poorly processed and accumulated in the endoplasmic reticulum of the transgenic melanotrope cells. In contrast, cleaved-Ac45 was efficiently transported through the secretory pathway, caused an accumulation of the V-ATPase at the plasma membrane and reduced dopaminergic inhibition of Ca2+-dependent peptide secretion. Surprisingly, removal of the C-tail from intact-Ac45 caused cellular phenotypes also found for cleaved-Ac45, whereas C-tail removal from cleaved-Ac45 still allowed its transport to the plasma membrane, but abolished V-ATPase recruitment into the secretory pathway and left dopaminergic inhibition of the cells unaffected. We conclude that domains located in the N- and C-terminal portions of the Ac45 protein direct its trafficking, V-ATPase recruitment and Ca2+-dependent-regulated exocytosis. PMID:22736765

  17. Identification of domains within the V-ATPase accessory subunit Ac45 involved in V-ATPase transport and Ca2+-dependent exocytosis.

    Science.gov (United States)

    Jansen, Eric J R; van Bakel, Nick H M; Olde Loohuis, Nikkie F M; Hafmans, Theo G M; Arentsen, Tim; Coenen, Anthon J M; Scheenen, Wim J J M; Martens, Gerard J M

    2012-08-10

    The vacuolar (H(+))-ATPase (V-ATPase) is crucial for maintenance of the acidic microenvironment in intracellular organelles, whereas its membrane-bound V(0)-sector is involved in Ca(2+)-dependent membrane fusion. In the secretory pathway, the V-ATPase is regulated by its type I transmembrane and V(0)-associated accessory subunit Ac45. To execute its function, the intact-Ac45 protein is proteolytically processed to cleaved-Ac45 thereby releasing its N-terminal domain. Here, we searched for the functional domains within Ac45 by analyzing a set of deletion mutants close to the in vivo situation, namely in transgenic Xenopus intermediate pituitary melanotrope cells. Intact-Ac45 was poorly processed and accumulated in the endoplasmic reticulum of the transgenic melanotrope cells. In contrast, cleaved-Ac45 was efficiently transported through the secretory pathway, caused an accumulation of the V-ATPase at the plasma membrane and reduced dopaminergic inhibition of Ca(2+)-dependent peptide secretion. Surprisingly, removal of the C-tail from intact-Ac45 caused cellular phenotypes also found for cleaved-Ac45, whereas C-tail removal from cleaved-Ac45 still allowed its transport to the plasma membrane, but abolished V-ATPase recruitment into the secretory pathway and left dopaminergic inhibition of the cells unaffected. We conclude that domains located in the N- and C-terminal portions of the Ac45 protein direct its trafficking, V-ATPase recruitment and Ca(2+)-dependent-regulated exocytosis.

  18. AC susceptibilities of grain-textured superconductors

    Science.gov (United States)

    Sakamoto, N.; Fukuda, Y.; Koga, M.; Akune, T.; Khan, H. R.; Lüders, K.

    2008-09-01

    In-phase χ n‧ and out-phase χ n″ components of nth harmonics of AC susceptibility with measuring parameters of a DC magnetic field Bdc, an amplitude Ba and a frequency f of the superimposed AC magnetic fields give substantial information of the superconducting properties. In low- Tc metallic superconductors, χ1‧ shows smooth transition and χ1″ does single peak. High- Tc oxide superconductors with anisotropic and grain-textured structures show deformed complex characteristics. Double peaks in χ1″ and shoulders in χ1‧ appear in AC susceptibility of Hg-1223 superconductors. Instead of simple Bean model, a grained model, where the superconducting grains are immersed in weak superconducting matrix, are proposed. The susceptibilities numerically analyzed using the model show varied and deformed curves and are successfully compared with the measured results.

  19. Nuclear structure of {sup 231}Ac

    Energy Technology Data Exchange (ETDEWEB)

    Boutami, R. [Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, E-28006 Madrid (Spain); Borge, M.J.G. [Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, E-28006 Madrid (Spain)], E-mail: borge@iem.cfmac.csic.es; Mach, H. [Department of Radiation Sciences, ISV, Uppsala University, SE-751 21 Uppsala (Sweden); Kurcewicz, W. [Department of Physics, University of Warsaw, Pl-00 681 Warsaw (Poland); Fraile, L.M. [Departamento Fisica Atomica, Molecular y Nuclear, Facultad CC. Fisicas, Universidad Complutense, E-28040 Madrid (Spain); ISOLDE, PH Department, CERN, CH-1211 Geneva 23 (Switzerland); Gulda, K. [Department of Physics, University of Warsaw, Pl-00 681 Warsaw (Poland); Aas, A.J. [Department of Chemistry, University of Oslo, PO Box 1033, Blindern, N-0315 Oslo (Norway); Garcia-Raffi, L.M. [Instituto de Fisica Corpuscular, CSIC - Universidad de Valencia, Apdo. 22805, E-46071 Valencia (Spain); Lovhoiden, G. [Department of Physics, University of Oslo, PO Box 1048, Blindern, N-0316 Oslo (Norway); Martinez, T.; Rubio, B.; Tain, J.L. [Instituto de Fisica Corpuscular, CSIC - Universidad de Valencia, Apdo. 22805, E-46071 Valencia (Spain); Tengblad, O. [Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, E-28006 Madrid (Spain); ISOLDE, PH Department, CERN, CH-1211 Geneva 23 (Switzerland)

    2008-10-15

    The low-energy structure of {sup 231}Ac has been investigated by means of {gamma} ray spectroscopy following the {beta}{sup -} decay of {sup 231}Ra. Multipolarities of 28 transitions have been established by measuring conversion electrons with a MINI-ORANGE electron spectrometer. The decay scheme of {sup 231}Ra {yields}{sup 231}Ac has been constructed for the first time. The Advanced Time Delayed {beta}{gamma}{gamma}(t) method has been used to measure the half-lives of five levels. The moderately fast B(E1) transition rates derived suggest that the octupole effects, albeit weak, are still present in this exotic nucleus.

  20. The Effective AC Response of Nonlinear Composites

    Institute of Scientific and Technical Information of China (English)

    WEI En-Bo; GU Guo-Qing

    2001-01-01

    A perturbative approach is used to study the AC response of nonlinear composite media, which obey a current-field relation of the form J = σ E + χ|E|2 E with components having nonlinear response at finite frequencies. For a sinusoidal applied field, we extend the local potential in terms of sinusoidal components at fundamental frequency and high-order harmonic frequencies to treat the nonlinear composites. For nonlinear composite media vith a low concentrations of spherical inclusions, we give the formulae of the nonlinear effective AC susceptibility χ*3ω at the third harmonic frequency.

  1. The ACS Nearby Galaxy Survey Treasury

    CERN Document Server

    Dalcanton, Julianne J; Seth, Anil C; Dolphin, Andrew; Holtzman, Jon; Rosema, Keith; Skillman, Evan D; Cole, Andrew; Girardi, Leo; Gogarten, Stephanie M; Karachentsev, Igor D; Olsen, Knut; Weisz, Daniel; Christensen, Charlotte; Freeman, Ken; Gilbert, Karoline; Gallart, Carme; Harris, Jason; Hodge, Paul; de Jong, Roelof S; Karachentseva, Valentina; Mateo, Mario; Stetson, Peter B; Tavarez, Maritza; Zaritsky, Dennis; Governato, Fabio; Quinn, Thomas

    2009-01-01

    The ACS Nearby Galaxy Survey Treasury (ANGST) is a systematic survey to establish a legacy of uniform multi-color photometry of resolved stars for a volume-limited sample of nearby galaxies (D14 million stars. In this paper we present the details of the sample selection, imaging, data reduction, and the resulting photometric catalogs, along with an analysis of the photometric uncertainties (systematic and random), for both t he ACS and WFPC2 imaging. We also present uniformly derived relative distances measured from the apparent magnitude of the TRGB.

  2. AC optik - visuaalisen identiteetin suunnittelu optikkoliikkeelle

    OpenAIRE

    Valén, Wilma

    2017-01-01

    Toteutin opinnäytetyöni yhdessä pienen loviisalaisen optikkoliikkeen, AC optikin kanssa. Opinnäytetyössäni suunnittelen AC optikille uuden visuaalisen ilmeen ja brändätyn pakkauksen, jossa silmälasit ja oheistavara on helppo luovuttaa asiakkaalle. Taustoitan aihettani yksityisyrittäjälle tärkeistä näkökulmista eli keskittymällä positiivisen asiakaskokemuksen tärkeyteen brändin rakentamisessa. Sen lisäksi käyn läpi visuaalisen identiteetin suunnittelun elementtejä ja pakkauksen asemaa brän...

  3. AC410 Unit 2 Homework Assignment

    OpenAIRE

    Laynebaril1

    2017-01-01

      AC410 Unit 2 Homework Assignment Click Link Below To Buy: http://hwcampus.com/shop/ac410-unit-2-homework-assignment/   3-31 Ron Barber, CPA, is auditing the financial statements of DGF, Inc., a publicly held company. During the course of the audit, Barber discovered that DGF has been making illegal bribes to foreign government officials to obtain business, and he reported the matter to senior management and the board of directors of DGF. Required: If management a...

  4. Control of Power Converters in AC Microgrids

    DEFF Research Database (Denmark)

    Rocabert, Joan; Luna, Alvaro; Blaabjerg, Frede

    2012-01-01

    The enabling of ac microgrids in distribution networks allows delivering distributed power and providing grid support services during regular operation of the grid, as well as powering isolated islands in case of faults and contingencies, thus increasing the performance and reliability of the ele......The enabling of ac microgrids in distribution networks allows delivering distributed power and providing grid support services during regular operation of the grid, as well as powering isolated islands in case of faults and contingencies, thus increasing the performance and reliability...

  5. Cascaded Buck-Boost AC/AC converter%级联式Buck-Boost AC/AC变换器

    Institute of Scientific and Technical Information of China (English)

    张友军; 丁明昌; 任永保; 王阿敏; 翁振明

    2010-01-01

    详细分析了Buck型和Boost型AC/AC变换器的工作原理及其控制方法,在此基础上提出了一种新型级联式Buck-Boost AC/AC变换器及其三模式控制策略.三模式控制策略是比较输入电压与基准输出电压的大小,使得变换器只有3种工作模式:Buck模式、Boost模式和滤波模式.该电路虽然由Buck型和Boost型AC/AC变换器2级变换器级联而成,并采用2级占空比调制,但实际上最多只存在一级功率变换,具有控制简单、变换效率高、开关管电压应力低等优点.仿真结果证明了级联式Buck-Boost AC/AC变换器及其控制策略的可行性和理论分析的正确性.

  6. Atmospheric pressure plasmas for aerosols processes in materials and environment

    Science.gov (United States)

    Borra, J. P.; Jidenko, N.; Bourgeois, E.

    2009-08-01

    The paper highlights applications of some atmospheric pressure plasmas (dc-corona, streamer and spark and ac-Dielectric Barrier Discharges) to aerosol processes for Materials and Environment (filtration, diagnostics). The production of vapor i.e. condensable gaseous species, leads to nano-sized particles by physical and chemical routes of nucleation in these AP plasmas: (i) when dc streamer and spark filamentary discharges as well as ac filamentary dielectric barrier discharges interact with metal or dielectric surfaces, and (ii) when discharges induce reactions with gaseous precursors in volume. It is shown how composition, size and structure of primary nano-particles are related to plasma parameters (energy, number per unit surface and time and thermal gradients). Then the growth by coagulation controls the final size of agglomerates versus plasma parameters and transit time in and after the plasma. Charging and electro-thermal collection are depicted to account for the related potential applications of controlled kinematics of charged aerosol.

  7. SINGLE PHASE HIGH FREQUENCY AC CONVERTER FOR INDUCTION HEATING APPLICATION

    Directory of Open Access Journals (Sweden)

    M.A INAYATHULLAAH,

    2010-12-01

    Full Text Available The proposed topology reduces the total harmonic distortion (THD of a high frequency AC/AC Converter well below the acceptable limit. This paper deals with a novel single phase AC/DC/AC soft switching utility frequency AC to high frequency AC converter. In this paper a single phase full bridge inverter with Vienna rectifier as front end is used instead of conventional diode bridge rectifier to provide continuous sinusoidal input current with nearly unity power factor at the source side with extremely low distortion.. This power converter is more suitable and acceptable for cost effective high frequency (HF consumer induction heating applications.

  8. YBCO thin films in ac and dc films

    CERN Document Server

    Shahzada, S

    2001-01-01

    We report studies on the dc magnetization of YBCO thin films in simultaneously applied dc and ac fields. The effect of the ac fields is to decrease the irreversible magnetization drastically leading to complete collapse of the hysteresis loops for relatively small ac fields (250e). The magnitude of the decrease depends on the component of the ac field parallel to the c-axis. The decrease is non-linear with ac amplitude and is explained in the framework of the critical state response of ultra thin films in perpendicular geometry. The ac fields increase the relaxation rapidly at short times while the long time response appears unaffected. (author)

  9. AcsA-AcsB: The core of the cellulose synthase complex from Gluconacetobacter hansenii ATCC23769.

    Science.gov (United States)

    McManus, John B; Deng, Ying; Nagachar, Nivedita; Kao, Teh-hui; Tien, Ming

    2016-01-01

    The gram-negative bacterium, Gluconacetobacter hansenii, produces cellulose of exceptionally high crystallinity in comparison to the cellulose of higher plants. This bacterial cellulose is synthesized and extruded into the extracellular medium by the cellulose synthase complex (CSC). The catalytic component of this complex is encoded by the gene AcsAB. However, several other genes are known to encode proteins critical to cellulose synthesis and are likely components of the bacterial CSC. We have purified an active heterodimer AcsA-AcsB from G. hansenii ATCC23769 to homogeneity by two different methods. With the purified protein, we have determined how it is post-translationally processed, forming the active heterodimer AcsA-AcsB. Additionally, we have performed steady-state kinetic studies on the AcsA-AcsB complex. Finally through mutagenesis studies, we have explored the roles of the postulated CSC proteins AcsC, AcsD, and CcpAx.

  10. Underwater operation of a DBD plasma jet

    Science.gov (United States)

    Foster, John E.; Weatherford, Brandon; Gillman, Eric; Yee, Benjamin

    2010-04-01

    A plasma jet produced in water using a submerged ac excited electrode in a coaxial dielectric barrier discharge configuration was studied. Plasma jet formation was found to occur only while the source was submerged. Plasma jet operation was characterized with and without gas flow. It was found that over 60% of the discharge power was deposited into the water and did not vary appreciably with excitation frequency. Presumably the remaining power fraction went into excitation, ionization and local electrode heating. Emission spectra of the jet revealed nitrogen, hydrogen, hydroxyl and oxygen emission lines. Operation of the plasma jet in water containing the oxidation-reduction indicator methylene blue dye resulted in a marked clearing of the water as observed visually and with a spectrophotometer, suggesting plasma-induced chemical reactivity.

  11. Thrombolytic effect of rAcAP5 and its mechanism%rAcAP5的溶栓作用及作用机制研究

    Institute of Scientific and Technical Information of China (English)

    丁双; 刘晓岩; 朱元军; 王银叶

    2012-01-01

    犬钩虫抗凝肽(Ancylostoma caninum anticoagulant peptide,AcAP5)是一种已报道的FXa抑制剂,它对防止血栓溶解的TAFIa具有很强的抑制作用,本文进一步研究rAcAP5的纤溶活性和溶栓活性.采用发色产物法测定rAcAP5对TAFIa的抑制作用,用比浊法测定rAcAP5对尿激酶(UK)诱导的纤维蛋白溶解时间的影响,通过血栓称重法进行体外溶栓实验和体内动静脉旁路溶栓实验.采用常规方法测定正常大鼠优球蛋白溶解时间(ELT),血浆纤维蛋白原含量和纤维蛋白降解产物(FDP)含量.rAcAP5浓度依赖地抑制TAFIa活性,其IC50为63.7 nmol/L,为一个强的TAFIa抑制剂.rAcAP5 (5-40 nmol/L)能够显著地加速尿激酶诱导纤维蛋白的溶解,缩短纤溶时间.rAcAP5能够提高尿激酶诱导的血栓减重(P<0.05),单独使用rAcAP5也能显著增加体外实验的血栓减重(P<0.05).在大鼠体内的动静脉旁路模型中,单次静脉给予rAcAP5 (50-200 μg/kg)能够剂量依赖地增加血栓减重(P<0.01).rAcAP5在有效剂量对正常大鼠的ELT、血浆纤维蛋白原含量和FDP含量均无明显影响.研究结果提示:rAcAP5是一个强效溶栓多肽,它可能通过抑制TAFIa的活性而在血栓表面具有溶栓活性,而不影响循环血液中的纤溶活性和纤维蛋白原含量.%Ancylostoma caninum anticoagulant peptide 5 (AcAP5) has been reported as an FXa inhibitor.We found that this peptide showed potent inhibitory activity on activated thrombin-activatable fibrinolysis inhibitor (TAFIa),which protects the fibrin clot against lysis.This study investigated the effects of recombinant AcAP5 (rAcAP5) on fibrinolytic activity in vitro and on thrombolytic activity in vitro and in vivo.In addition,euglobulin lysis time (ELT),fibrinogen content and fibrin degradation product (FDP) in normal rat plasma were all determined to evaluate the influence of rAcAP5 on fibrinolytic activity in circulation blood.TAFIa activity was detected by colorimetry

  12. Modeling of long High Voltage AC Underground

    DEFF Research Database (Denmark)

    Gudmundsdottir, Unnur Stella; Bak, Claus Leth; Wiechowski, W. T.

    2010-01-01

    This paper presents the work and findings of a PhD project focused on accurate high frequency modelling of long High Voltage AC Underground cables. The project is cooperation between Aalborg University and Energinet.dk. The objective of the project is to investigate the accuracy of most up to date...

  13. Protection of AC and DC Microgrids

    DEFF Research Database (Denmark)

    Beheshtaein, Siavash; Savaghebi, Mehdi; Quintero, Juan Carlos Vasquez

    2015-01-01

    In future, distributed energy resources (RESs) will be utilized at consumption points. As a consequence, power flow and fault current would be bidirectional and topologydependent; and hence the conventional protection strategies would be inefficient. This paper categorizes the main challenges in AC...

  14. 76 FR 65633 - RIN 1904-AC43

    Science.gov (United States)

    2011-10-24

    ... 1904-AC43. Comments may be submitted using any of the following methods: Federal eRulemaking Portal... and avoid the use of special characters or any form of encryption. Postal Mail: Ms. Brenda Edwards, U... FR 56678 (September 14, 2011) to make available and invite comments on the framework document...

  15. Operating experience with factory-made air-insulated 1AC/2AC switchgear systems; Erste Betriebserfahrungen mit fabrikgefertigten, luftisolierten 1AC-/2AC-Schaltanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Northe, J. [Balfour Beatty Rail GmbH, Offenbach (Germany); Loenard, D. [Bombardier Transportation GmbH, Mannheim (Germany)

    2007-07-01

    Today, factory-made air-insulated switchgear systems of the type TracFeed {sup registered} are available for all supply versions of 16.7 Hz and 50 Hz a.c. railways. These are supported by auxiliary equipment to ensure reliable railway operation through specific protective functions and a simplified line test. (orig.)

  16. Thermal Simulation of AC Electromagnetic Contactor

    Institute of Scientific and Technical Information of China (English)

    NIUChun-ping; CHENDe-gui; ZHANGJing-shu; LIXing-wen

    2005-01-01

    Transient magnetic circuit method is adopted to calculate the power loss in winding and shading coil. Based on the analysis of heat transfer process in AC contactor, a thermal model is proposed and the temperature field distribution is simulated with 3-D FEM of ANSYS.Comparison of simulation results with measurements shows that the proposed method is effective.

  17. AC Losses of Prototype HTS Transmission Cables

    Energy Technology Data Exchange (ETDEWEB)

    Demko, J.A.; Dresner, L.; Hughey, R.L.; Lue, J.W.; Olsen, S.K.; Sinha, U.; Tolbert, J.C.

    1998-09-13

    Since 1995 Southwire Company and Oak Ridge National Laboratory (ORNL) have jointly designed, built, and tested nine, l-m long, high temperature superconducting (HTS) transmission cable prototypes. This paper summarizes the AC loss measurements of five of the cables not reported elsewhere, and compares the losses with each other and with theory developed by Dresner. Losses were measured with both a calorimetric and an electrical technique. Because of the broad resistive transition of the HTS tapes, the cables can be operated stably beyond their critical currents. The AC losses were measured in this region as well as below critical currents. Dresner's theory takes into account the broad resistive transition of the HTS tapes and calculates the AC losses both below and above the critical current. The two sets of AC 10SS data agree with each other and with the theory quite welL In particular, at low currents of incomplete penetration, the loss data agree with the theoretical prediction of hysteresis loss based on only the outer two Iayers carrying the total current.

  18. AC power generation from microbial fuel cells

    Science.gov (United States)

    Lobo, Fernanda Leite; Wang, Heming; Forrestal, Casey; Ren, Zhiyong Jason

    2015-11-01

    Microbial fuel cells (MFCs) directly convert biodegradable substrates to electricity and carry good potential for energy-positive wastewater treatment. However, the low and direct current (DC) output from MFC is not usable for general electronics except small sensors, yet commercial DC-AC converters or inverters used in solar systems cannot be directly applied to MFCs. This study presents a new DC-AC converter system for MFCs that can generate alternating voltage in any desired frequency. Results show that AC power can be easily achieved in three different frequencies tested (1, 10, 60 Hz), and no energy storage layer such as capacitors was needed. The DC-AC converter efficiency was higher than 95% when powered by either individual MFCs or simple MFC stacks. Total harmonic distortion (THD) was used to investigate the quality of the energy, and it showed that the energy could be directly usable for linear electronic loads. This study shows that through electrical conversion MFCs can be potentially used in household electronics for decentralized off-grid communities.

  19. From Beamline to Scanner with 225Ac

    Science.gov (United States)

    Robertson, Andrew K. H.; Ramogida, Caterina F.; Kunz, Peter; Rodriguez-Rodriguez, Cristina; Schaffer, Paul; Sossi, Vesna

    2016-09-01

    Due to the high linear energy transfer and short range of alpha-radiation, targeted radiation therapy using alpha-emitting pharmaceuticals that successfully target small disease clusters will kill target cells with limited harm to healthy tissue, potentially treating the most aggressive forms of cancer. As the parent of a decay chain with four alpha- and two beta-decays, 225Ac is a promising candidate for such a treatment. However, this requires retention of the entire decay chain at the target site, preventing the creation of freely circulating alpha-emitters that reduce therapeutic effect and increase toxicity to non-target tissues. Two major challenges to 225Ac pharmaceutical development exist: insufficient global supply, and the difficulty of preventing toxicity by retaining the entire decay chain at the target site. While TRIUMF works towards large-scale (C i amounts) production of 225Ac, we already use our Isotope Separation On-Line facility to provide small (overview of this research program and the journey of 225Ac from the beamline to the scanner. This research is funded by the Natural Sciences and Engineering Research Council of Canada.

  20. A dry-cooled AC quantum voltmeter

    Science.gov (United States)

    Schubert, M.; Starkloff, M.; Peiselt, K.; Anders, S.; Knipper, R.; Lee, J.; Behr, R.; Palafox, L.; Böck, A. C.; Schaidhammer, L.; Fleischmann, P. M.; Meyer, H.-G.

    2016-10-01

    The paper describes a dry-cooled AC quantum voltmeter system operated up to kilohertz frequencies and 7 V rms. A 10 V programmable Josephson voltage standard (PJVS) array was installed on a pulse tube cooler (PTC) driven with a 4 kW air-cooled compressor. The operating margins at 70 GHz frequencies were investigated in detail and found to exceed 1 mA Shapiro step width. A key factor for the successful chip operation was the low on-chip power consumption of 65 mW in total. A thermal interface between PJVS chip and PTC cold stage was used to avoid a significant chip overheating. By installing the cryocooled PJVS array into an AC quantum voltmeter setup, several calibration measurements of dc standards and calibrator ac voltages up to 2 kHz frequencies were carried out to demonstrate the full functionality. The results are discussed and compared to systems with standard liquid helium cooling. For dc voltages, a direct comparison measurement between the dry-cooled AC quantum voltmeter and a liquid-helium based 10 V PJVS shows an agreement better than 1 part in 1010.

  1. Aging, Counterfeiting Configuration Control (AC3)

    Science.gov (United States)

    2010-01-31

    relabeled fake microcircuit chips from overseas - threaten the reliability, safety, and performance of DoD systems. These systems are vulnerable... NASA , Raytheon internal, etc. Aging, Counterfeiting Configuration Control (AC3) Page 13 of 28 are important in determining the alert’s priority

  2. Synthesis and structures of calcium and strontium 2,4-di-tert-butylphenolates and their reactivity towards the amine co-initiated ring-opening polymerisation of rac-lactide.

    Science.gov (United States)

    Clark, Lawrence; Deacon, Glen B; Forsyth, Craig M; Junk, Peter C; Mountford, Philip; Townley, Josh P; Wang, Jun

    2013-07-07

    Calcium and strontium metals react with Hg(C6F5)2 and 2,4-di-tert-butylphenol (H-DBP) in tetrahydrofuran (THF) and 1,2-dimethoxyethane (DME) to give [Ca(DBP)2(THF)4] (1), [Ca2(DBP)4(DME)4(μ-DME)] (2), [Sr3(μ-DBP)6(THF)6] (3), and [Sr2(DBP)(μ-DBP)3(DME)3] (4). Compound 1 is a six coordinate trans-octahedral monomer, whereas in binuclear 2 two seven-coordinate Ca centres are bridged by a DME ligand. In 3 a central Sr is connected by three bridging DBP groups to each of two terminal Sr(THF)3 moieties, all metal atoms being six coordinate. Compound 4 has one six- and one seven-coordinate Sr, bridged by three DBP ligands, the former Sr also having a terminal DBP and a bidentate DME ligand and the latter two DME ligands. Complexes 2 and 4 act as ring-opening polymerisation (ROP) catalysts for the benzyl alcohol or benzylamine co-initiated ROP rac-lactide forming atactic alcohol- or amine-terminated polylactide H-[PLA]-XBn (X = O or NH) with reasonable control of molecular weight via an activated monomer propagation mechanism. Kinetic studies for BnNH2 found the unusual rate expression -d[LA]/dt = k(p(Ae))[2 or 4]0[rac-LA](2)[BnNH2]0(2.5) (k(p(Ca)) ≈ 1.7 ×k(p(Sr))). Preliminary studies suggest that [Y(DBP)3(THF)2] also catalyses amine or alcohol co-initiated ROP by an activated monomer mechanism without loss of a phenoxide ligand.

  3. Implementation and Control of an AC/DC/AC Converter for Double Wound Flywheel Application

    Directory of Open Access Journals (Sweden)

    J. G. Oliveira

    2012-01-01

    Full Text Available An all-electric driveline based on a double wound flywheel, connected in series between main energy storage and a wheel motor, is presented. The flywheel works as a power buffer, allowing the battery to deliver optimized power. It also separates electrically the system in two sides, with the battery connected to the low voltage side and the wheel motor connected to the high voltage side. This paper presents the implementation and control of the AC/DC/AC converter, used to connect the flywheel high voltage windings to the wheel motor. The converter general operation and the adopted control strategy are discussed. The implementation of the AC/DC/AC converter has been described from a practical perspective. Results from experimental tests performed in the full-system prototype are presented. The prototype system is running with satisfactory stability during acceleration mode. Good efficiency and unity power factor could be achieved, based on vector control and space vector modulation.

  4. Digital model for harmonic interactions in AC/DC/AC systems

    Energy Technology Data Exchange (ETDEWEB)

    Guarini, A.P.; Rangel, R.D.; Pilotto, L.A.S.; Pinto, R.J.; Passos Junior, R. [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil)

    1994-12-31

    The main purpose of this paper is to present a model for calculation of HVdc converter harmonics taking into account the influence of the harmonic interactions between the ac systems in dc link transmissions. The ideas and methodologies used in the model development take into account the dc current ripple and ac voltage distortion in the ac systems. The theory of switching functions is applied to contemplate for the frequency conversions between the ac and dc sides, in an iterative process. It is possible then to obtain, even in balanced situations, non-characteristic harmonics that are produced by frequencies originated in the other terminal, which can be significant in a strongly coupled system, such as back-to-back configuration. (author) 9 refs., 3 figs.

  5. AcEST Contig - AcEST | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us ...contig.zip File URL: ftp://ftp.biosciencedbc.jp/archive/acest/LATEST/acestcontig....zip File size: 1.34MB Simple search URL http://togodb.biosciencedbc.jp/togodb/view/archive_acestcontig#en Da...Joomla SEF URLs by Artio About This Database Database Description Download License Update History of This Database Site Policy | Contact Us AcEST Contig - AcEST | LSDB Archive ...

  6. Avaliação analítica de sistemas de introdução de amostra para a determinação de elementos traço em extratos lixiviados contendo ácido acético por espectrometria de massa com plasma indutivamente acoplado

    OpenAIRE

    Gois, Jefferson Santos de

    2012-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas. Programa de Pós-Graduação em Química No Brasil, os procedimentos para a classificação dos resíduos sólidos em relação à sua toxicidade levam em consideração a solubilidade e biodisponibilidade de metais por meio de experimentos de extração utilizando soluções contendo ácido acético e hidróxido de sódio. A análise de soluções contendo compostos orgânicos e elementos de baixo potencial ...

  7. Dicty_cDB: FCL-AC21 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available FCL (Link to library) FCL-AC21 (Link to dictyBase) - - - Contig-U15479-1 FCL-AC21E ...(Link to Original site) - - - - - - FCL-AC21E 632 Show FCL-AC21 Library FCL (Link to library) Clone ID FCL-AC2... http://dictycdb.biol.tsukuba.ac.jp/CSM/FCL/FCL-AC/FCL-AC21Q.Seq.d/ Representative seq. ID FCL-AC2...1E (Link to Original site) Representative DNA sequence >FCL-AC21 (FCL-AC21Q) /CSM/FCL/FCL-AC/FCL-AC2...M/SL/SLG7-D/SLG773Q.Seq.d/ 1205 0.0 FCL-AC21 (FCL-AC21Q) /CSM/FCL/FCL-AC/FCL-AC21

  8. Electron Temperature and Plasma Flow Measurements of NIF Hohlraum Plasmas

    Science.gov (United States)

    Barrios, M. A.; Liedahl, D. A.; Schneider, M. B.; Jones, O.; Brow, G. V.; Regan, S. P.; Fournier, K. B.; Moore, A. S.; Ross, J. S.; Eder, D.; Landen, O.; Kauffman, R. L.; Nikroo, A.; Kroll, J.; Jaquez, J.; Huang, H.; Hansen, S. B.; Callahan, D. A.; Hinkel, D. E.; Bradley, D.; Moody, J. D.; LLNL Collaboration; LLE Collaboration; GA Collaboration; SNL Collaboration

    2016-10-01

    Characterizing the plasma conditions inside NIF hohlraums, in particular mapping the plasma Te, is critical to gaining insight into mechanisms that affect energy coupling and transport in the hohlraum. The dot spectroscopy platform provides a temporal history of the localized Te and plasma flow inside a NIF hohlraum, by introducing a Mn-Co tracer dot, at strategic locations inside the hohlraum, that comes to equilibrium with the local plasma. K-shell X-ray spectroscopy of the tracer dot is recorded onto an absolutely calibrated X-ray streak spectrometer. Isoelectronic and interstage line ratios are used to infer localized Te through comparison with atomic physics calculations using SCRAM. Time resolved X-ray images are simultaneously taken of the expanding dot, providing plasma (ion) flow information. We present recent results provided by this platform and compare with simulations using HYDRA. This work was performed under the auspices of the U.S. Department of Energy by LLNL under Contract DE-AC52-07NA27344.

  9. Morphological studies of the galaxy populations in distant "Butcher-Oemler" clusters with HST. II. AC103, AC118 and AC114 at z=0.31

    CERN Document Server

    Couch, W J; Smail, I; Ellis, Richard S; Sharples, R M

    1997-01-01

    We present new results of a program to study the detailed morphologies of galaxies in intermediate redshift clusters and hence understand the physical origin of the enhanced star formation in these environments at earlier epochs. Deep, high resolution imagery has been obtained of 3 rich clusters, AC103,AC118 & AC114 at z=0.31, using the WFPC2 on HST. For AC103 & AC118, single pointings covering a central 0.5x0.5Mpc have been obtained; for AC114, 4 pointings covering a 1.2x0.7Mpc area have been obtained, allowing the more outer regions of a distant cluster to be studied. Hubble types plus evidence for dynamical interactions and/or structural abnormalities have been determined visually for all galaxies down to R=22.25 in AC103 & AC118 and R=23.0 in AC114.We find the numbers of spirals (Sa-Sdm) in our clusters to be up to 4x higher than that seen in present-day clusters; only in the virialised core of our most massive regular cluster, AC114, do we see morphological fractions approaching those of the ...

  10. Plasma Antenna

    OpenAIRE

    N M Vijay

    2014-01-01

    The fundamental base of plasma antenna is the use of an ionized medium as a conductor. The plasma antenna is a radiofrequency antenna formed by a plasma columns, Filaments or sheets, which are excited by a surface wave. The relevance of this device is how rapidly it can be turned on and off, only applying an electrical pulse. Besides its wide carrier frequency, the great directivity and controllable antenna shape. Otherwise a disadvantage is that it needs energy to be ionized....

  11. Methods for Addressing Missing Data with Applications from ACS Exams

    Science.gov (United States)

    Brandriet, Alexandra; Holme, Thomas

    2015-01-01

    As part of the ACS Examinations Institute (ACS-EI) national norming process, student performance data sets are collected from professors at colleges and universities from around the United States. Because the data sets are collected on a volunteer basis, the ACS-EI often receives data sets with only students' total scores and without the students'…

  12. Importance of Attenuation Correction (AC) for Small Animal PET Imaging

    DEFF Research Database (Denmark)

    El Ali, Henrik H.; Bodholdt, Rasmus Poul; Jørgensen, Jesper Tranekjær;

    2012-01-01

    was performed. Methods: Ten NMRI nude mice with subcutaneous implantation of human breast cancer cells (MCF-7) were scanned consecutively in small animal PET and CT scanners (MicroPETTM Focus 120 and ImTek’s MicroCATTM II). CT-based AC, PET-based AC and uniform AC methods were compared. Results: The activity...

  13. Plasma physics

    CERN Document Server

    Drummond, James E

    2013-01-01

    A historic snapshot of the field of plasma physics, this fifty-year-old volume offers an edited collection of papers by pioneering experts in the field. In addition to assisting students in their understanding of the foundations of classical plasma physics, it provides a source of historic context for modern physicists. Highly successful upon its initial publication, this book was the standard text on plasma physics throughout the 1960s and 70s.Hailed by Science magazine as a ""well executed venture,"" the three-part treatment ranges from basic plasma theory to magnetohydrodynamics and microwa

  14. AC LED的研究现状与发展%Current research and development of AC LED

    Institute of Scientific and Technical Information of China (English)

    满瑞; 李秋俊

    2012-01-01

    介绍了AC LED的特征及其工作原理,分析了AC LED相比于DC LED的优缺点,概述了AC LED在国内外的研究进展及其应用现状,讨论了AC LED技术发展过程中面临的挑战,并展望了其发展趋势.%The characteristics and operation principles of AC LED were presented.The advantages and disadvantages of AC LED compared with the DC LED were analyzed.The development and the latest application of AC LED were described.The challenges of the competition with the traditional light source were discussed,as well as the development trend of AC LED.

  15. Plasma dynamics of a laser filamentation-guided spark

    CERN Document Server

    Point, Guillaume; Carbonnel, Jérôme; Mysyrowicz, André; Houard, Aurélien

    2016-01-01

    We investigate experimentally the plasma dynamics of a centimeter-scale, laser filamentation-guided spark discharge. Using electrical and optical diagnostics to study monopolar discharges with varying current pulses we show that plasma decay is dominated by free electron recombination if the current decay time is shorter than the recombination characteristic time. In the opposite case, the plasma electron density closely follows the current evolution. We demonstrate that this criterion holds true in the case of damped AC sparks, and that alternative current is the best option to achieve a long plasma lifetime for a given peak current.

  16. RHIC AC DIPOLE DESIGN AND CONSTRUCTION.

    Energy Technology Data Exchange (ETDEWEB)

    BAI,M.; METH,M.; PAI,C.; PARKER,B.; PEGGS,S.; ROSER,T.; SANDERS,R.; TRBOJEVIC,D.; ZALTSMAN,A.

    2001-06-18

    Two ac dipoles with vertical and horizontal magnetic field have been proposed at RHIC for applications in linear and non-linear beam dynamics and spin manipulations. A magnetic field amplitude of 380 Gm is required to produce a coherent oscillation of 5 times the rms beam size at the top energy. We take the ac dipole frequency to be 1.0% of the revolution frequency away from the betatron frequency. To achieve the strong magnetic field with minimum power loss, an air-core magnet with two seven turn winding of low loss Litz wire resonating at 64 kHz is designed. The system is also designed to allow one to connect the two magnet winding in series to resonate at 37 kHz for the spin manipulation. Measurements of a half length prototype magnet are also presented.

  17. Nanorod dynamics in ac electric fields

    Energy Technology Data Exchange (ETDEWEB)

    Ruda, H E; Shik, A [Centre for Advanced Nanotechnology, University of Toronto, Toronto, M5S 3E3 (Canada)

    2010-06-11

    Metal and semiconductor nanorods polarized by an external electric field tend to align parallel to this field. We derived the equation of motion for this alignment, taking into account electrostatic forces, thermal fluctuations and viscous resistance of the liquid the nanorods are suspended in. It was solved for a strong ac electric field, as well as for the combination of strong dc and weak ac fields. The results were used for calculations of the capacity of the nanorod solution, its frequency dispersion and dependence on the field strength. Modification of the nanorod absorption spectra under the influence of an electric field was also considered. It was shown that metal nanorods in laser radiation, with the frequency belonging to the interval between longitudinal and transverse plasmon modes, tend to align perpendicular, rather than parallel, to the optical electric field.

  18. 78 FR 49318 - Availability of Draft Advisory Circular (AC) 90-106A and AC 20-167A

    Science.gov (United States)

    2013-08-13

    ... Systems (78 FR 34935-34958) (Docket No.: FAA-2013-0485; Notice No. 1209). AC 90-106A, Enhanced Flight... the Federal Register published on April 11, 2000 (65 FR 19477-19478), as well as at http://DocketsInfo... Federal Aviation Administration Availability of Draft Advisory Circular (AC) 90-106A and AC 20-...

  19. Lazy AC-Pattern Matching for Rewriting

    OpenAIRE

    Walid Belkhir; Alain Giorgetti

    2012-01-01

    We define a lazy pattern-matching mechanism modulo associativity and commutativity. The solutions of a pattern-matching problem are stored in a lazy list composed of a first substitution at the head and a non-evaluated object that encodes the remaining computations. We integrate the lazy AC-matching in a strategy language: rewriting rule and strategy application produce a lazy list of terms.

  20. Lazy AC-Pattern Matching for Rewriting

    Directory of Open Access Journals (Sweden)

    Walid Belkhir

    2012-04-01

    Full Text Available We define a lazy pattern-matching mechanism modulo associativity and commutativity. The solutions of a pattern-matching problem are stored in a lazy list composed of a first substitution at the head and a non-evaluated object that encodes the remaining computations. We integrate the lazy AC-matching in a strategy language: rewriting rule and strategy application produce a lazy list of terms.

  1. Cryocooled Josephson standards for AC voltage metrology

    Science.gov (United States)

    Durandetto, P.; Sosso, A.; Monticone, E.; Trinchera, B.; Fretto, M.; Lacquaniti, V.

    2017-05-01

    The Josephson effect is worldwide used as a basis for constant reference voltages in national metrological institutes and in calibration laboratories of industry. Research on Josephson voltage standards is aiming at a fundamental change also in the metrology of the volt for AC and arbitrary waveforms: programmable Josephson voltage standards converting a digital code into a quantum-accurate stepwise waveform are already available in primary laboratories and even more advanced standards for converting sub-nanosecond binary coded pulses into any arbitrary signal with quantum accuracy are now actively developed and tested. A new experimental setup based on a two-stage Gifford-McMahon cryocooler has been developed at INRiM for the operation of AC-Josephson voltage standards. Among its distinct features, the possibility of employing both the aforementioned techniques (programmable and pulsed Josephson voltage standards) is particularly interesting. Quantum-based AC voltage sine waves have been synthesized with both programmable and pulse-driven arrays, although their accuracy is still limited by thermal oscillations due to the cryocooler piston motion.

  2. The Hubble Legacy Archive ACS Grism Data

    CERN Document Server

    Kuemmel, M; Fosbury, R; Haase, J; Hook, R N; Kuntschner, H; Lombardi, M; Micol, A; Nilsson, K K; Stoehr, F; Walsh, J R

    2011-01-01

    A public release of slitless spectra, obtained with ACS/WFC and the G800L grism, is presented. Spectra were automatically extracted in a uniform way from 153 archival fields (or "associations") distributed across the two Galactic caps, covering all observations to 2008. The ACS G800L grism provides a wavelength range of 0.55-1.00 \\mu$m, with a dispersion of $40 \\ \\AA / pixel$ and a resolution of $\\sim 80\\ \\AA$ for point-like sources. The ACS G800L images and matched direct images were reduced with an automatic pipeline that handles all steps from archive retrieval, alignment and astrometric calibration, direct image combination, catalogue generation, spectral extraction and collection of metadata. The large number of extracted spectra (73,581) demanded automatic methods for quality control and an automated classification algorithm was trained on the visual inspection of several thousand spectra. The final sample of quality controlled spectra includes 47,919 datasets (65% of the total number of extracted spect...

  3. AC susceptibilities of grain-textured superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Sakamoto, N. [Department of Electrical Engineering, Kyushu Sangyo University, 2-3-1 Matsukadai, 813-8503 Fukuoka (Japan)], E-mail: saka@te.kyusan-u.ac.jp; Fukuda, Y.; Koga, M.; Akune, T. [Department of Electrical Engineering, Kyushu Sangyo University, 2-3-1 Matsukadai, 813-8503 Fukuoka (Japan); Khan, H.R. [Institut von Ionenstrahl und Vakuum Technologie, 73728 Esslingen (Germany); Lueders, K. [Freie Universitaet Berlin, Arnimallee, Fac.Physik, D-14195 Berlin (Germany)

    2008-09-15

    In-phase {chi}{sub n}' and out-phase {chi}{sub n}'' components of nth harmonics of AC susceptibility with measuring parameters of a DC magnetic field B{sub dc}, an amplitude B{sub a} and a frequency f of the superimposed AC magnetic fields give substantial information of the superconducting properties. In low-T{sub c} metallic superconductors, {chi}{sub 1}' shows smooth transition and {chi}{sub 1}'' does single peak. High-T{sub c} oxide superconductors with anisotropic and grain-textured structures show deformed complex characteristics. Double peaks in {chi}{sub 1}'' and shoulders in {chi}{sub 1}' appear in AC susceptibility of Hg-1223 superconductors. Instead of simple Bean model, a grained model, where the superconducting grains are immersed in weak superconducting matrix, are proposed. The susceptibilities numerically analyzed using the model show varied and deformed curves and are successfully compared with the measured results.

  4. The anti-inflammatory peptide Ac-SDKP is released from thymosin-β4 by renal meprin-α and prolyl oligopeptidase.

    Science.gov (United States)

    Kumar, Nitin; Nakagawa, Pablo; Janic, Branislava; Romero, Cesar A; Worou, Morel E; Monu, Sumit R; Peterson, Edward L; Shaw, Jiajiu; Valeriote, Frederick; Ongeri, Elimelda M; Niyitegeka, Jean-Marie V; Rhaleb, Nour-Eddine; Carretero, Oscar A

    2016-05-15

    N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) is a natural tetrapeptide with anti-inflammatory and antifibrotic properties. Previously, we have shown that prolyl oligopeptidase (POP) is involved in the Ac-SDKP release from thymosin-β4 (Tβ4). However, POP can only hydrolyze peptides shorter than 30 amino acids, and Tβ4 is 43 amino acids long. This indicates that before POP hydrolysis takes place, Tβ4 is hydrolyzed by another peptidase that releases NH2-terminal intermediate peptide(s) with fewer than 30 amino acids. Our peptidase database search pointed out meprin-α metalloprotease as a potential candidate. Therefore, we hypothesized that, prior to POP hydrolysis, Tβ4 is hydrolyzed by meprin-α. In vitro, we found that the incubation of Tβ4 with both meprin-α and POP released Ac-SDKP, whereas no Ac-SDKP was released when Tβ4 was incubated with either meprin-α or POP alone. Incubation of Tβ4 with rat kidney homogenates significantly released Ac-SDKP, which was blocked by the meprin-α inhibitor actinonin. In addition, kidneys from meprin-α knockout (KO) mice showed significantly lower basal Ac-SDKP amount, compared with wild-type mice. Kidney homogenates from meprin-α KO mice failed to release Ac-SDKP from Tβ4. In vivo, we observed that rats treated with the ACE inhibitor captopril increased plasma concentrations of Ac-SDKP, which was inhibited by the coadministration of actinonin (vehicle, 3.1 ± 0.2 nmol/l; captopril, 15.1 ± 0.7 nmol/l; captopril + actinonin, 6.1 ± 0.3 nmol/l; P Ac-SDKP after actinonin treatment. We conclude that release of Ac-SDKP from Tβ4 is mediated by successive hydrolysis involving meprin-α and POP.

  5. 单相直接AC-AC变换器的实现与分析%The Implementation and Analysis of Simple Phase Direct AC-AC Converter

    Institute of Scientific and Technical Information of China (English)

    万衡; 喻嬿; 黄道

    2002-01-01

    针对传统AC-DC-AC变换存在的缺陷,采用高频调制直接AC-AC变换技术,实现了两种不同结构的单相AC-AC直接变换器,对其特点和仿真结果进行了分析,并探讨了应用前景.

  6. Generation of radiation by intense plasma and electromagnetic undulators

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, C.

    1991-10-01

    We examine the characteristics of the classical radiation emission resulting from the interaction of a relativistic electron beam that propagates perpendicularly through a large amplitude relativistic plasma wave. Such a study is useful for evaluating the feasibility of using relativistic plasma waves as extremely short wavelength undulators for generating short wavelength radiation. The electron trajectories in a plasma wave undulator and in an ac FEL undulator are obtained using perturbation techniques. The spontaneous radiation frequency spectrum and angular distribution emitted by a single electron oscillating in these two undulators are then calculated. The radiation gain of a copropagating electromagnetic wave is calculated. The approximate analytic results for the trajectories, spontaneous radiation and gain are compared with 3-D simulation results. The characteristics of the plasma wave undulator are compared with the ac FEL undulator and linearly polarized magnetic undulator. 50 refs., 26 figs., 3 tabs.

  7. Increased plasma citrulline in mice marks diet-induced obesity and may predict the development of the metabolic syndrome

    NARCIS (Netherlands)

    Sailer, M.; Dahlhoff, C.; Giesbertz, P.; Eidens, M.K.; Wit, de N.J.W.; Rubio-Aliaga, I.; Boekschoten, M.V.; Müller, M.R.; Daniel, H.

    2013-01-01

    Article About the Authors Metrics Comments Related Content Abstract Introduction Results Discussion Materials and Methods Supporting Information Acknowledgments Author Contributions References Reader Comments (0) Figures Abstract In humans, plasma amino acid concentrations of branched-chain amino ac

  8. Molecular biology of maize Ac/Ds elements: an overview.

    Science.gov (United States)

    Lazarow, Katina; Doll, My-Linh; Kunze, Reinhard

    2013-01-01

    Maize Activator (Ac) is one of the prototype transposable elements of the hAT transposon superfamily, members of which were identified in plants, fungi, and animals. The autonomous Ac and nonautonomous Dissociation (Ds) elements are mobilized by the single transposase protein encoded by Ac. To date Ac/Ds transposons were shown to be functional in approximately 20 plant species and have become the most widely used transposable elements for gene tagging and functional genomics approaches in plants. In this chapter we review the biology, regulation, and transposition mechanism of Ac/Ds elements in maize and heterologous plants. We discuss the parameters that are known to influence the functionality and transposition efficiency of Ac/Ds transposons and need to be considered when designing Ac transposase expression constructs and Ds elements for application in heterologous plant species.

  9. Development of a hardware-based AC microgrid for AC stability assessment

    Science.gov (United States)

    Swanson, Robert R.

    As more power electronic-based devices enable the development of high-bandwidth AC microgrids, the topic of microgrid power distribution stability has become of increased interest. Recently, researchers have proposed a relatively straightforward method to assess the stability of AC systems based upon the time-constants of sources, the net bus capacitance, and the rate limits of sources. In this research, a focus has been to develop a hardware test system to evaluate AC system stability. As a first step, a time domain model of a two converter microgrid was established in which a three phase inverter acts as a power source and an active rectifier serves as an adjustable constant power AC load. The constant power load can be utilized to create rapid power flow transients to the generating system. As a second step, the inverter and active rectifier were designed using a Smart Power Module IGBT for switching and an embedded microcontroller as a processor for algorithm implementation. The inverter and active rectifier were designed to operate simultaneously using a synchronization signal to ensure each respective local controller operates in a common reference frame. Finally, the physical system was created and initial testing performed to validate the hardware functionality as a variable amplitude and variable frequency AC system.

  10. A Sensitivity Analysis of SOLPS Plasma Detachment

    Science.gov (United States)

    Green, D. L.; Canik, J. M.; Eldon, D.; Meneghini, O.; AToM SciDAC Collaboration

    2016-10-01

    Predicting the scrape off layer plasma conditions required for the ITER plasma to achieve detachment is an important issue when considering divertor heat load management options that are compatible with desired core plasma operational scenarios. Given the complexity of the scrape off layer, such predictions often rely on an integrated model of plasma transport with many free parameters. However, the sensitivity of any given prediction to the choices made by the modeler is often overlooked due to the logistical difficulties in completing such a study. Here we utilize an OMFIT workflow to enable a sensitivity analysis of the midplane density at which detachment occurs within the SOLPS model. The workflow leverages the TaskFarmer technology developed at NERSC to launch many instances of the SOLPS integrated model in parallel to probe the high dimensional parameter space of SOLPS inputs. We examine both predictive and interpretive models where the plasma diffusion coefficients are chosen to match an empirical scaling for divertor heat flux width or experimental profiles respectively. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility, and is supported under Contracts DE-AC02-05CH11231, DE-AC05-00OR22725 and DE-SC0012656.

  11. 隔离式SEPIC三电平AC-AC变换器的研究%Research of Isolated SEPIC Three-level AC - AC Converter

    Institute of Scientific and Technical Information of China (English)

    周振军; 李磊

    2011-01-01

    电力电子装置已在电力系统中得到了越来越广泛的应用,代表之一就是交流调压稳压装置.但是目前的交流调压稳压器多数采用AC-DC-AC的变换方式,这种调压稳压器不仅体积大、噪音大,而且开关管的电压应力大、输出电压波形质量低.提出了一种新型的隔离式交-交变换器,它是在sepic变换器(单端初级电感转换器)的基础上引入了推挽式变压器实现电气隔离.分析了工作原理,给出了控制策略,并通过仿真论证了变换器开关管电压应力小、输出电压波形质量高等特点.%Power electronics have been more widely used in power systems. One representative of power electronics is AC voltage regulator. But the AC - DC - AC conversion type is widely used for voltage regulator now. These AC voltage regulator not only have big bulk and high noise,but also with high power switch voltage stress and low quality of output waveform. To solve these problems)an isolated three-level AC - AC direct converter was proposed. It joined the push-pull transformer to achieve electrical isolation based on sepic AC -AC converter. Its operation principle and control strategies of the converter were investigated. By modeling and simulation,the performances of the AC - AC converter were verified, such as low switch voltage stress, high quality of output waveform and so on.

  12. Plasma Treated Active Carbon for Capacitive Deionization of Saline Water

    Directory of Open Access Journals (Sweden)

    Aiping Zeng

    2017-01-01

    Full Text Available The plasma treatment on commercial active carbon (AC was carried out in a capacitively coupled plasma system using Ar + 10% O2 at pressure of 4.0 Torr. The RF plasma power ranged from 50 W to 100 W and the processing time was 10 min. The carbon film electrode was fabricated by electrophoretic deposition. Micro-Raman spectroscopy revealed the highly increased disorder of sp2 C lattice for the AC treated at 75 W. An electrosorption capacity of 6.15 mg/g was recorded for the carbon treated at 75 W in a 0.1 mM NaCl solution when 1.5 V was applied for 5 hours, while the capacity of the untreated AC was 1.01 mg/g. The plasma treatment led to 5.09 times increase in the absorption capacity. The jump of electrosorption capacity by plasma treatment was consistent with the Raman spectra and electrochemical double layer capacitance. This work demonstrated that plasma treatment was a potentially efficient approach to activating biochar to serve as electrode material for capacitive deionization (CDI.

  13. Involvement of Lipid Rafts and Cellular Actin in AcMNPV GP64 Distribution and Virus Budding

    Institute of Scientific and Technical Information of China (English)

    F. J. Haines; C. M. Griffiths; R. D. Possee; C. R. Hawes; L. A. King

    2009-01-01

    GP64 is the major envelope glycoprotein associated with the budded virus (BV) of Autographa californica nucleopolyhedrovirus (AcMNPV) and is essential for attachment and budding of BV particles.Confocal microscopy and flotation assays established the presence of lipid raft domains within the plasma membranes of AcMNPV-infected Sf9 cells and suggested the association of GP64 with lipid rafts during infection. GP64 and filamentous actin (F-actin) were found to co-localise at the cell cortex at 24 and 48 hpi and an additional restructuring of F-actin during infection was visualised, resulting in a strongly polarised distribution of both F-actin and GP64 at the cell cortex. Depletion of F-actin, achieved by treatment of St9 cells with latrunculin B (LB), resulted in the redistribution of GP64 with significant cytoplasmic aggregation and reduced presence at the plasma membrane. Treatment with LB also resulted in reduced production of BV in Sf9 cells. Analysis of virus gene transcription confirmed this reduction was not due to decreased trafficking of nucleocapsids to the nucleus or to decreased production of infectious progeny nucleoeapsids. Reduced BV production due to a lack of GP64 at the plasma membrane of AcMNPV-infected Sf9 cells treated with LB, suggests a key role for F-actin in the egress of BV.

  14. Plasma chromograninx

    DEFF Research Database (Denmark)

    Goetze, Jens P; Hilsted, Linda M; Rehfeld, Jens F

    2014-01-01

    Cardiovascular risk assessment remains difficult in elderly patients. We examined whether chromogranin A (CgA) measurement in plasma may be valuable in assessing risk of death in elderly patients with symptoms of heart failure in a primary care setting. A total of 470 patients (mean age 73 years......) were followed for 10 years. For CgA plasma measurement, we used a two-step method including a screening test and a confirmative test with plasma pre-treatment with trypsin. Cox multivariable proportional regression and receiver-operating curve (ROC) analyses were used to assess mortality risk...... of follow-up showed significant additive value of CgA confirm measurements compared with NT-proBNP and clinical variables. CgA measurement in the plasma of elderly patients with symptoms of heart failure can identify those at increased risk of short- and long-term mortality....

  15. Plasma Cleaning

    Science.gov (United States)

    Hintze, Paul E.

    2016-01-01

    NASA's Kennedy Space Center has developed two solvent-free precision cleaning techniques: plasma cleaning and supercritical carbon dioxide (SCCO2), that has equal performance, cost parity, and no environmental liability, as compared to existing solvent cleaning methods.

  16. MATHEMATICAL MODELING OF AC ELECTRIC POINT MOTOR

    Directory of Open Access Journals (Sweden)

    S. YU. Buryak

    2014-03-01

    Full Text Available Purpose. In order to ensure reliability, security, and the most important the continuity of the transportation process, it is necessary to develop, implement, and then improve the automated methods of diagnostic mechanisms, devices and rail transport systems. Only systems that operate in real time mode and transmit data on the instantaneous state of the control objects can timely detect any faults and thus provide additional time for their correction by railway employees. Turnouts are one of the most important and responsible components, and therefore require the development and implementation of such diagnostics system.Methodology. Achieving the goal of monitoring and control of railway automation objects in real time is possible only with the use of an automated process of the objects state diagnosing. For this we need to know the diagnostic features of a control object, which determine its state at any given time. The most rational way of remote diagnostics is the shape and current spectrum analysis that flows in the power circuits of railway automatics. Turnouts include electric motors, which are powered by electric circuits, and the shape of the current curve depends on both the condition of the electric motor, and the conditions of the turnout maintenance. Findings. For the research and analysis of AC electric point motor it was developed its mathematical model. The calculation of parameters and interdependencies between the main factors affecting the operation of the asynchronous machine was conducted. The results of the model operation in the form of time dependences of the waveform curves of current on the load on engine shaft were obtained. Originality. During simulation the model of AC electric point motor, which satisfies the conditions of adequacy was built. Practical value. On the basis of the constructed model we can study the AC motor in various mode of operation, record and analyze current curve, as a response to various changes

  17. Plasma confinement

    CERN Document Server

    Hazeltine, R D

    2003-01-01

    Detailed and authoritative, this volume examines the essential physics underlying international research in magnetic confinement fusion. It offers readable, thorough accounts of the fundamental concepts behind methods of confining plasma at or near thermonuclear conditions. Designed for a one- or two-semester graduate-level course in plasma physics, it also represents a valuable reference for professional physicists in controlled fusion and related disciplines.

  18. Flexible AC transmission systems modelling and control

    CERN Document Server

    Zhang, Xiao-Ping; Pal, Bikash

    2012-01-01

    The extended and revised second edition of this successful monograph presents advanced modeling, analysis and control techniques of Flexible AC Transmission Systems (FACTS). The book covers comprehensively a range of power-system control problems: from steady-state voltage and power flow control, to voltage and reactive power control, to voltage stability control, to small signal stability control using FACTS controllers. In the six years since the first edition of the book has been published research on the FACTS has continued to flourish while renewable energy has developed into a mature and

  19. Composite Based EHV AC Overhead Transmission Lines

    DEFF Research Database (Denmark)

    Sørensen, Thomas Kjærsgaard

    Overhead lines at transmission level are the backbone of any national power grid today. New overhead line projects however are at the same time subject to ever greater public resistance due to the lines environmental impact. As full undergrounding of transmission lines at extra high voltage (EHV...... and analysed with regard to the possibilities, limitations and risks widespread application of composite materials on EHV AC overhead transmission lines may present. To form the basis for evaluation of the useability of composite materials, dierent overhead line projects aimed at reducing the environmental...

  20. DC injection into low voltage AC networks

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This report summarises the results of a study investigating the impact of levels of injected DC current injections on a low voltage AC distribution network systems in order to recommend acceptable limits of DC from microgeneration. Relevant literature is reviewed, and the impact of DC levels in distribution transformers, transformer modelling, and instrumental transformers are discussed. The impact of DC in residual current devices (RCD) and in domestic electricity watt hour meters is examined along with DC enhanced corrosion, corrosion failure, and the measurement of DC current injection. Sources of DC injection outlined include DC from computer power supplies, network faults, geomagnetic phenomena, lighting circuits/dimmers, and embedded generators.

  1. POWER FACTOR IMPROVEMENT IN THREE PHASE AC-AC CONVERTER THROUGH MODIFIED SPWM

    Directory of Open Access Journals (Sweden)

    P.VASUKI,

    2011-02-01

    Full Text Available Recently, a new generation of ac-ac single-phase and three-phase power converters with more commutations per half cycle has been proposed for ac power due to the increasing availability and power capability of high frequency controlled-on and off power emiconductor switching devices. This paper presents three phase ac-acconverter whose control strategy is based on modified sinusoidal ulse-width modulation switching technique. As majority of the industrial loads are being inductive, the power factor is less. To improve the power factor, the delayed current is shifted to the input voltage, through a modification of the classical sinusoidal pulse width modulation switching technique. In this way, the decrease in the phase angle between the input current and voltage is feasible, and consequently, high cost compensation capacitors can be avoided. The improvement of power factor through this switching technique on the proposed converter is investigated and verified via simulation using the software Matlab/Simulink.

  2. Theoretical study of electromagnetic electron cyclotron waves in the presence of AC field in Uranian magnetosphere

    Science.gov (United States)

    Pandey, R. S.; Kaur, Rajbir

    2015-10-01

    Electromagnetic electron cyclotron (EMEC) waves with temperature anisotropy in the magnetosphere of Uranus have been studied in present work. EMEC waves are investigated using method of characteristic solution by kinetic approach, in presence of AC field. In 1986, Voyager 2 encounter with Uranus revealed that magnetosphere of Uranus exhibit non-Maxwellian high-energy tail distribution. So, the dispersion relation, real frequency and growth rate are evaluated using Lorentzian Kappa distribution function. Effect of temperature anisotropy, AC frequency and number density of particles is found. The study is also extended to oblique propagation of EMEC waves in presence and absence of AC field. Through comprehensive mathematical analysis it is found that when EMEC wave propagates parallel to intrinsic magnetic field of Uranus, its growth is more enhanced than in case of oblique propagation. Results are also discussed in context to magnetosphere of Earth and also gives theoretical explanation to existence of high energetic particles observed by Voyager 2 in the magnetosphere of Uranus. The results can present a further insight into the nature of electron-cyclotron instability condition for the whistler mode waves in the outer radiation belts of Uranus or other space plasmas.

  3. C/NOFS Observations of AC Electric Field Fields Associated with Equatorial Spread-F

    Science.gov (United States)

    Pfaff, R.; Liebrecht, C.

    2009-01-01

    The Vector Electric Field Investigation (VEFI) on the C/NOFS equatorial satellite provides a unique data set in which to acquire detailed knowledge of irregularities associated with the equatorial ionosphere and in particular with spread-F depletions. We present vector AC electric field observations, primarily gathered within the ELF band (1 Hz to 250 Hz) on C/NOFS that address a variety of key questions regarding how plasma irregularities, from meter to kilometer scales, are created and evolve. The data will be used to explore the anisotropy/isotropy of the waves, their wavelength and phase velocity, as well as their spectral distributions. When analyzed in conjunction with the driving DC electric fields and detailed plasma number density measurements, the combined data reveal important information concerning the instability mechanisms themselves. We also present high resolution, vector measurements of intense lower hybrid waves that have been detected on numerous occasions by the VEFI burst memory VLF electric field channels.

  4. Cascading failures in ac electricity grids

    Science.gov (United States)

    Rohden, Martin; Jung, Daniel; Tamrakar, Samyak; Kettemann, Stefan

    2016-09-01

    Sudden failure of a single transmission element in a power grid can induce a domino effect of cascading failures, which can lead to the isolation of a large number of consumers or even to the failure of the entire grid. Here we present results of the simulation of cascading failures in power grids, using an alternating current (AC) model. We first apply this model to a regular square grid topology. For a random placement of consumers and generators on the grid, the probability to find more than a certain number of unsupplied consumers decays as a power law and obeys a scaling law with respect to system size. Varying the transmitted power threshold above which a transmission line fails does not seem to change the power-law exponent q ≈1.6 . Furthermore, we study the influence of the placement of generators and consumers on the number of affected consumers and demonstrate that large clusters of generators and consumers are especially vulnerable to cascading failures. As a real-world topology, we consider the German high-voltage transmission grid. Applying the dynamic AC model and considering a random placement of consumers, we find that the probability to disconnect more than a certain number of consumers depends strongly on the threshold. For large thresholds the decay is clearly exponential, while for small ones the decay is slow, indicating a power-law decay.

  5. Electrothermally driven flows in ac electrowetting.

    Science.gov (United States)

    García-Sánchez, Pablo; Ramos, Antonio; Mugele, Frieder

    2010-01-01

    Mixing within sessile drops can be enhanced by generating internal flow patterns using ac electrowetting. While for low ac frequencies, the flow patterns have been attributed to oscillations of the drop surface, we provide here the driving mechanism of the hitherto unexplained high-frequency flows. We show that: (1) the electric field in the liquid bulk becomes important, leading to energy dissipation due to Joule heating and a temperature increase of several degrees Celsius, and (2) the fluid flow at these frequencies is generated by electrothermal effect, i.e., gradients in temperature give rise to gradients in conductivity and permittivity, the electric field acting on these inhomogeneities induces an electrical body force that generates the flow. We solved numerically the equations for the electric, temperature and flow fields. The temperature is obtained from a convection-diffusion equation where Joule heating is introduced as a source term. From the solution of the electric field and the temperature, we compute the electrical force that acts as a body force in Stokes equations. Our numerical results agree with previous experimental observations.

  6. Djungle power. A more remote AC bus

    Energy Technology Data Exchange (ETDEWEB)

    Boehnke, Heinz W. [Technosol, Jork (Germany)

    2010-07-01

    The Dzanga-Sangha Reserve in the Central African Republic is probably one of the world's most remote protected rainforest areas, much to the benefit of the rare species of lowland gorilla, forest elephant and local pygmy population Ba'Aka. The park is co-managed by the ''WWF-World Wide Fund for Nature'' with sponsoring from the German Regenwald-Stiftung. In 2008 wwf decided to switch from the old, failing generator supply to a solar hybrid mini-grid, along with stringent measures of energy conservation and management. After a careful energy audit Technosol designed an AC-bus system with a 22 kWp PV generator which should overcome the dependency on the old generators and their fuel demands. For 15 buildings, an entirely new distribution network was installed, state of the art energy saving devices introduced and an energy metering system deviced. The installation is operating since August 2009. In such remote locations, the reliability of the AC-bus over other generator-based solutions will be demonstrated and with the support of international organisations like the wwf the practical application of solar hybrid supply becomes a landmark of sustainable energy concepts. (orig.)

  7. Magnetic irreversibility in granular superconductors: ac susceptibility study

    Energy Technology Data Exchange (ETDEWEB)

    Perez, F.; Obradors, X.; Fontcuberta, J. (ICMAB, CSIC, Bellaterra, Barcelona (Spain)); Vallet, M.; Gonzalez-Calbet, J. (Lab. Magnetismo Aplicado, RENFE-U.C. Madrid, Las Matas (Spain))

    1991-12-01

    Ac susceptibility measurements of a ceramic weak-coupled superconductor in very low ac fields (2mG, 111Hz) are reported. We present evidence for the observation of the magnetic irreversibility following a ZFC-FC thermal cycling by means of ac susceptibilty measurements. It is shown that this technique also reflect local magnetic field effects in granular superconductors, as previously suggested in microwave surface resistance and I-V characteristics. (orig.).

  8. Transport AC Losses in Striated YBCO Coated Conductors (Postprint)

    Science.gov (United States)

    2012-02-01

    AFRL-RZ-WP-TP-2012-0124 TRANSPORT AC LOSSES IN STRIATED YBCO COATED CONDUCTORS (POSTPRINT) G.A. Levin and P.N. Barnes Mechanical Energy...TRANSPORT AC LOSSES IN STRIATED YBCO COATED CONDUCTORS (POSTPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...2006. 14. ABSTRACT DC current-voltage characteristics and transport ac losses of striated and non-striated Y1Ba2Cu3O7-δ ( YBCO ) coated conductors

  9. Plasma carnitine concentrations after chronic alcohol intoxication 

    Directory of Open Access Journals (Sweden)

    Alina Kępka

    2013-05-01

    Full Text Available Background: Carnitine transports fatty acids from the cytoplasm to the mitochondrial matrix, where the fatty acids are oxidized. Chronic alcohol consumption reduces the concentration of carnitine and interferes with oxidative processes occurring in the cell.Aim: The assessment of carnitine concentrations in plasma of chronically intoxicated alcohol dependent persons in a 49-day abstinence period.Material/Methods: The study included 31 patients (5 women and 27 men aged from 26 to 60 years (44.6± 8.9 and 32 healthy subjects (15 women and 17 men aged 22-60 years (39.8± 9.4. The patients’ alcohol dependence ranged from 2 to 30 years (13.6± 7.5. Examined subjects consumed 75-700 g of ethanol/day (226.9± 151.5. Plasma concentrations of free and total carnitine were measured three times: at the first (T0, 30th (T30 and 49th (T49 day of hospital detoxification. Free (FC and total (TC carnitine were determined by the spectrophotometric method. Plasma acylcarnitine (AC concentration was calculated from the difference between TC and FC; then the AC/FC ratio was calculated. To determine statistically significant differences for related variables, Student’s t-test was used.Results: At T0, alcoholics had significantly lower concentration of FC and TC (p < 0.05 in plasma, as compared to the control group. In comparison to controls, at T30, plasma TC and FC (p < 0.01 as well as AC (p < 0.001 were reduced. The lowest concentration of TC, FC and AC (p < 0.001was found at T49. The ratio of AC/FC at T0 had a tendency to be higher in alcoholics than in the control group (p = 0.05, whereas at T49 it was significantly lower in alcoholics as compared to the control subjects (p < 0.05.Conclusions: Chronic alcohol intoxication causes a plasma deficiency of carnitine. Forty-nine days of abstinence showed a significant decrease in the concentration of TC, FC and AC. Further research is necessary to clarify whether a low level of plasma carnitine

  10. AC electric motors control advanced design techniques and applications

    CERN Document Server

    Giri, Fouad

    2013-01-01

    The complexity of AC motor control lies in the multivariable and nonlinear nature of AC machine dynamics. Recent advancements in control theory now make it possible to deal with long-standing problems in AC motors control. This text expertly draws on these developments to apply a wide range of model-based control designmethods to a variety of AC motors. Contributions from over thirty top researchers explain how modern control design methods can be used to achieve tight speed regulation, optimal energetic efficiency, and operation reliability and safety, by considering online state var

  11. Autonomous Operation of Hybrid Microgrid With AC and DC Subgrids

    DEFF Research Database (Denmark)

    Chiang Loh, Poh; Li, Ding; Kang Chai, Yi

    2013-01-01

    This paper investigates on power-sharing issues of an autonomous hybrid microgrid. Unlike existing microgrids which are purely ac, the hybrid microgrid studied here comprises dc and ac subgrids interconnected by power electronic interfaces. The main challenge here is to manage power flows among all...... sources distributed throughout the two types of subgrids, which is certainly tougher than previous efforts developed for only ac or dc microgrid. This wider scope of control has not yet been investigated, and would certainly rely on the coordinated operation of dc sources, ac sources, and interlinking...

  12. AC Own Motion Percentage of Randomly Sampled Cases

    Data.gov (United States)

    Social Security Administration — Longitudinal report detailing the numbers and percentages of Appeals Council (AC) own motion review actions taken on un-appealed favorable hearing level decisions...

  13. plasma treatment

    Directory of Open Access Journals (Sweden)

    Puač Nevena

    2014-11-01

    Full Text Available In this paper we will present results for plasma sterilization of planktonic samples of two reference strains of bacteria, Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212. We have used a plasma needle as a source of non-equilibrium atmospheric plasma in all treatments. This device is already well characterized by OES, derivative probes and mass spectrometry. It was shown that power delivered to the plasma is bellow 2 W and that it produces the main radical oxygen and nitrogen species believed to be responsible for the sterilization process. Here we will only present results obtained by electron paramagnetic resonance which was used to detect the OH, H and NO species. Treatment time and power delivered to the plasma were found to have the strongest influence on sterilization. In all cases we have observed a reduction of several orders of magnitude in the concentration of bacteria and for the longest treatment time complete eradication. A more efficient sterilization was achieved in the case of gram negative bacteria.

  14. Plasma metallization

    CERN Document Server

    Crowther, J M

    1997-01-01

    Many methods are currently used for the production of thin metal films. However, all of these have drawbacks associated with them, for example the need for UHV conditions, high temperatures, exotic metal precursors, or the inability to coat complex shaped objects. Reduction of supported metal salts by non-isothermal plasma treatment does not suffer from these drawbacks. In order to produce and analyse metal films before they become contaminated, a plasma chamber which could be attached directly to a UHV chamber with XPS capability was designed and built. This allowed plasma treatment of supported metal salts and surface analysis by XPS to be performed without exposure of the metal film to the atmosphere. Non-equilibrium plasma treatment of Nylon 66 supported gold(lll) chloride using hydrogen as the feed gas resulted in a 95% pure gold film, the remaining 5% of the film being carbon. If argon or helium were used as the feed gases during plasma treatment the resultant gold films were 100% pure. Some degree of s...

  15. Is plasma urotensin II concentration an indicator of myocardial damage in patients with acute coronary syndrome?

    OpenAIRE

    Babińska, Magdalena; Holecki, Michał; Prochaczek, Fryderyk; OWCZAREK, ALEKSANDER; Kokocińska, Danuta; Chudek,Jerzy; Więcek, Andrzej

    2012-01-01

    Introduction Urotensin II (UII) is a vasoactive peptide secreted by endothelial cells. Increased plasma UII concentration was observed in patients with heart failure, liver cirrhosis, diabetic nephropathy and renal insufficiency. In patients with myocardial infarction both increased and decreased plasma UII concentrations were demonstrated. The aim of this study was to analyze whether plasma UII concentration reflects the severity of acute coronary syndrome (ACS). Material and methods One hun...

  16. Metabolism evaluation of the anticancer candidate AC04 by biomimetic oxidative model and rat liver microsomes.

    Science.gov (United States)

    Pigatto, Maiara Cássia; Alves de Lima, Maria do Carmo; Galdino, Suely Lins; Pitta, Ivan da Rocha; Vessecchi, Ricardo; Assis, Marilda das Dores; dos Santos, Joicy Santamalvina; Dalla Costa, Teresa; Lopes, Norberto Peporine

    2011-09-01

    Jacobsen reagents, in the presence of monooxygen donors, appear as an alternative to produce metabolites from biological active compounds. This reaction may mimic the oxidation and oxygenation reactions of cytochrome P450 (CYP450) enzymes upon various drugs and biologically active compounds. Acridines represent a well-known group of polyaromatic compounds capable of acting as DNA intercalating agents. Viewing to search for new anticancer agents, one promising new acridine, the 5-acridin-9-ylmethylene-3-(4-methyl-benzyl)-thiazolidine-2,4-dione (AC04) (2), has been studied by our group and the in vitro metabolism was investigated in this work, aiming to advance in the pre-clinical pharmacokinetic investigation. A systematic investigation of the gas-phase reaction, supported by computational chemistry, of the AC04 (2) was studied to help the structure elucidation of possible in vivo metabolites. To confirm the methodology, the oxidized product was obtained in large scale for NMR analysis and the data confirmed the structure. In addition, AC04 (2) was submitted to an in vitro metabolism assay employing rat liver microsomes and also, a pilot study was conducted in rats after AC04 intravenous (i.v.) dosing of 1.5 mg/kg. A single oxidized product was obtained from microsomal metabolism and detected in rat plasma by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis corresponding to the same product formed by Jacobsen-catalyzed reaction. These results indicate that Jacobsen oxidation reactions, combined with in vitro metabolism assays employing isolated microsomes, might replace some in vivo metabolism studies, thus reducing the use of animals in new chemical entities pre-clinical investigation.

  17. Plasma dynamo

    CERN Document Server

    Rincon, F; Schekochihin, A A; Valentini, F

    2015-01-01

    Magnetic fields pervade the entire Universe and, through their dynamical interactions with matter, affect the formation and evolution of astrophysical systems from cosmological to planetary scales. How primordial cosmological seed fields arose and were further amplified to $\\mu$Gauss levels reported in nearby galaxy clusters, near equipartition with kinetic energy of plasma motions and on scales of at least tens of kiloparsecs, is a major theoretical puzzle still largely unconstrained by observations. Extragalactic plasmas are weakly collisional (as opposed to collisional magnetohydrodynamic fluids), and whether magnetic-field growth and its sustainment through an efficient dynamo instability driven by chaotic motions is possible in such plasmas is not known. Fully kinetic numerical simulations of the Vlasov equation in a six-dimensional phase space necessary to answer this question have until recently remained beyond computational capabilities. Here, we show by means of such simulations that magnetic-field a...

  18. Characteristics of ac capillary discharge produced in electrically conductive water solution

    Science.gov (United States)

    DeBaerdemaeker, F.; Simek, M.; Schmidt, J.; Leys, C.

    2007-05-01

    Basic electrical, optical and calorimetric characteristics of an ac (50 Hz) driven capillary discharge produced in a water solution were studied for initial water solution conductivity in the range 50-1000 µS cm-1. Typical current and voltage waveforms and emission intensities produced by several electronically excited species were recorded with high time resolution. The evolution of the electrical current, power and capillary resistance was inspected during positive ac half-cycle for various operational regimes. A fast relaxation of the discharge following a breakdown event was observed. Optical measurements indicate that radiative species are mostly generated during the first few hundreds of nanoseconds of plasma generation and that the average duration of plasma emission induced by a discharge pulse is of the order of a few microseconds. Results of calorimetric measurements are in good agreement with average electrical measurements and support the assumption that the discharge is a constant source of heat delivered to the liquid. Assuming that only a fraction of the heat released inside the capillary can be transported by conduction through the capillary wall and via its orifices, the processes of bubble formation, expulsion and re-filling the capillary with 'fresh' water must play a key role in maintaining a thermal balance during long-time steady-state operation of the device. Furthermore, a simplified numerical model and a first order energy deposition calculation prove the plausibility of the bubble breakdown mechanism.

  19. [Intestinal occlusion and abdominal compartment syndrome (ACS)].

    Science.gov (United States)

    Stagnitti, Franco

    2009-01-01

    Intestinal occlusion is defined as an independent predictive factor of intra-abdominal hypertension (IAH) which represents an independent predictor of mortality. Baggot in 1951 classified patients operated with intestinal occlusion as being at risk for IAH ("abdominal blow-out"), recommending them for open abdomen surgery proposed by Ogilvie. Abdominal surgery provokes IAH in 44.7% of cases with mortality which, in emergency, triples with respect to elective surgery (21.9% vs 6.8%). In particular, IAH is present in 61.2% of ileus and bowel distension and is responsible for 52% of mortality (54.8% in cases with intra-abdominal infection). These patients present with an increasing intra-abdominal pressure (IAP) which, over 20-25 mmHg, triggers an Abdominal Compartment Syndrome (ACS) with altered functions in some organs arriving at Multiple Organ Dysfunction Syndrome (MODS). The intestine normally covers 58% of abdominal volume but when there is ileus distension, intestinal pneumatosis develops (third space) which can occupy up to 90% of the entire cavity. At this moment, Gastro Intestinal Failure (GIF) can appear, which is a specific independent risk factor of mortality, motor of "Organ Failure". The pathophysiological evolution has many factors in 45% of cases: intestinal pneumatosis is associated with mucosal and serous edema, capillary leakage with an increase in extra-cellular volume and peritoneal fluid collections (fourth space). The successive loss of the mucous barrier permits a bacterial translocation which includes bacteria, toxins, pro-inflammatory factors and oxygen free radicals facilitating the passage from an intra-abdominal to inter-systemic vicious cyrcle. IAH provokes the raising of the diaphragm, and vascular and visceral compressions which induce hypertension in the various spaces with compartmental characteristics. These trigger hypertension in the renal, hepatic, pelvic, thoracic, cardiac, intracranial, orbital and lower extremity areas, giving

  20. Plasma medicine

    CERN Document Server

    Fridman, Alexander

    2012-01-01

    This comprehensive text is suitable for researchers and graduate students of a 'hot' new topic in medical physics. Written by the world's leading experts,  this book aims to present recent developments in plasma medicine, both technological and scientific, reviewed in a fashion accessible to the highly interdisciplinary audience consisting of doctors, physicists, biologists, chemists and other scientists, university students and professors, engineers and medical practitioners. The book focuses on major topics and covers the physics required to develop novel plasma discharges relevant for medic

  1. A Non-linear Controller for Single-Phase AC-AC Power Converter to meet UPS Performance Index

    Directory of Open Access Journals (Sweden)

    Abdelhafid Ait Elmahjoub

    2012-07-01

    Full Text Available This article focuses on AC-AC power converter that can be used for uninterruptible power supply (UPS. The converter is built on two stages: a AC-DC input stage and a DC-AC output stage. The two blocks are connected by an intermediate DC bus. The aim of control is threefold: i power factor correction ii regulation of DC bus iii generating a sinusoidal voltage at the output. The synthesis of controllers has been achieved through the technique of nonlinear backstepping control. A detailed analysis of the stability control system is presented. The performances of regulators have been validated by numerical simulation in MATLAB / SIMULINK.

  2. Measurement of the ultrasonic attenuation coefficient of human blood plasma during clotting in the frequency range of 8 to 22 MHz.

    Science.gov (United States)

    Calor-Filho, Marcos Muniz; Machado, João Carlos

    2006-07-01

    The blood coagulation mechanism consists of a series of concatenated chemical reactions, governed by the coagulation factors present in the blood plasma, after the activation of the clot mechanism. The last reaction corresponds to the fibrinogen conversion into fibrin, followed by the fibrin polymerisation and production of a stable fibrin network. During the clotting process, there is a sol-gel transformation of the medium. The subject of the present paper is the measurement of the ultrasonic attenuation coefficient for human blood plasma during the coagulation process, in the frequency range of 8 to 22 MHz. The clot was obtained after the procedure to measure the prothrombin time (approximately 12 s): mixing 150 microL of reconstituted lyophilised normal plasma with 300 microL of reconstituted lyophilised thromboplastin immersed in a water bath with the temperature controlled at 36.5 degrees C. The attenuation coefficient for pure plasma remained constant within the measurement period of 10 s and at frequencies of 8, 9, 10, 15, 20, 21 and 22 MHz. On the other hand, there is a detectable time-decay of the attenuation coefficient for samples of plasma going through the coagulation process and at frequencies of 8, 9, 10 and 15 MHz. The time-decay becomes less and less detectable as the frequency increases and it becomes completely undetectable at 20, 21 and 22 MHz.

  3. AC Dielectrophoresis Using Elliptic Electrode Geometry

    Directory of Open Access Journals (Sweden)

    S. M. Rezaul Hasan

    2011-01-01

    Full Text Available This paper presents negative AC dielectrophoretic investigations using elliptic electrode geometry. Simulations of the electric field gradient variation using various ratios of the semimajor and the semiminor axis were carried out to determine the optimum elliptic geometry for the dielectrophoretic electrokinetics of specimen in an assay with laminar (low Reynolds number fluid flow. Experimental setup of the elliptic electrode assembly using PCB fabrication and electrokinetic accumulation of specimen in a dielectrophoretic cage is also being reported. Using an actuating signal between 1 kHz and 1 MHz, successful trapping of 45 μm polystyrene beads suspended in distilled water was demonstrated due to negative dielectrophoresis near 100 kHz using the novel elliptic electrode.

  4. Effective ac response in weakly nonlinear composites

    Energy Technology Data Exchange (ETDEWEB)

    Wei Enbo [Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071 (China); Yang Zidong [College of Power Engineering, University of Shanghai Science and Technology, Shanghai 200093 (China); Gu Guoqing [Information College of Science and Technology, East China Normal University, Shanghai 200062 (China)

    2004-01-07

    The perturbation method is developed to deal with the problem of determining the effective nonlinear conductivity of Kerr-like nonlinear media under an external ac electric field. As an example, we have considered the cylindrical inclusion embedded in a host under the sinusoidal external field E{sub 1} sin (<{omega}t) + E{sub 3} sin (3<{omega}t) with frequencies{omega} and 3{omega}. The potentials of composites at higher harmonics are derived in both local inclusion particle and host regions. The effective responses of bulk nonlinear composites at basic frequency and harmonics are given for cylindrical composites in the dilute limit. Moreover, the relationships between the nonlinear effective responses at the basic frequency and the third harmonics are derived.

  5. Fuzzy efficiency optimization of AC induction motors

    Science.gov (United States)

    Jani, Yashvant; Sousa, Gilberto; Turner, Wayne; Spiegel, Ron; Chappell, Jeff

    1993-01-01

    This paper describes the early states of work to implement a fuzzy logic controller to optimize the efficiency of AC induction motor/adjustable speed drive (ASD) systems running at less than optimal speed and torque conditions. In this paper, the process by which the membership functions of the controller were tuned is discussed and a controller which operates on frequency as well as voltage is proposed. The membership functions for this dual-variable controller are sketched. Additional topics include an approach for fuzzy logic to motor current control which can be used with vector-controlled drives. Incorporation of a fuzzy controller as an application-specific integrated circuit (ASIC) microchip is planned.

  6. ac impedance of the carbon monofluoride electrode

    Science.gov (United States)

    Suchanski, M. R.

    1985-09-01

    The ac impedance of carbon monofluoride (CF) half-cells and Li/CF batteries that contain 1M LiBF4/4-butyrolactone electrolyte was measured as a function of state of charge. The nonfaradaic components of the CF half-cell impedance were resolved with the aid of a one-dimensional macroscopic treatment of a porous electrode. The values of the nonfaradaic components and their variation with charge withdrawn provide information concerning the nature of cathode discharge products, the degree of tortuosity in the cathode and separator matrices, and the cathode failure mechanism. The CF electrode capacitance, as measured by the low frequency quadrature impedance, can serve as a semiquantitative measure of battery state of charge under certain conditions.

  7. The AC and DC Conductivity of Nanocomposites

    Directory of Open Access Journals (Sweden)

    David S. McLachlan

    2007-01-01

    Full Text Available The microstructures of binary (conductor-insulator composites, containing nanoparticles, will usually have one of two basic structures. The first is the matrix structure where the nanoparticles (granules are embedded in and always coated by the matrix material and there are no particle-particle contacts. The AC and DC conductivity of this microstructure is usually described by the Maxwell-Wagner/Hashin-Shtrikman or Bricklayer model. The second is a percolation structure, which can be thought to be made up by randomly packing the two types of granules (not necessarily the same size together. In percolation systems, there exits a critical volume fraction below which the electrical properties are dominated by the insulating component and above which the conducting component dominates. Such percolation systems are best analyzed using the two-exponent phenomenological percolation equation (TEPPE. This paper discusses all of the above and addresses the problem of how to distinguish among the microstructures using electrical measurements.

  8. Transcranial alternating current stimulation (tACS

    Directory of Open Access Journals (Sweden)

    Andrea eAntal

    2013-06-01

    Full Text Available Transcranial alternating current stimulation (tACS seems likely to open a new era of the field of noninvasive electrical stimulation of the human brain by directly interfering with cortical rhythms. It is expected to synchronize (by one single resonance frequency or desynchronize (e.g. by the application of several frequencies cortical oscillations. If applied long enough it may cause neuroplastic effects. In the theta range it may improve cognition when applied in phase. Alpha rhythms could improve motor performance, whereas beta intrusion may deteriorate them. TACS with both alpha and beta frequencies has a high likelihood to induce retinal phosphenes. Gamma intrusion can possibly interfere with attention. Stimulation in the ripple range induces intensity dependent inhibition or excitation in the motor cortex most likely by entrainment of neuronal networks, whereas stimulation in the low kHz range induces excitation by neuronal membrane interference. TACS in the 200 kHz range may have a potential in oncology.

  9. Characterization of the mucosal and systemic immune response induced by Cry1Ac protein from Bacillus thuringiensis HD 73 in mice

    Directory of Open Access Journals (Sweden)

    Vázquez-Padrón R.I.

    2000-01-01

    Full Text Available The present paper describes important features of the immune response induced by the Cry1Ac protein from Bacillus thuringiensis in mice. The kinetics of induction of serum and mucosal antibodies showed an immediate production of anti-Cry1Ac IgM and IgG antibodies in serum after the first immunization with the protoxin by either the intraperitoneal or intragastric route. The antibody fraction in serum and intestinal fluids consisted mainly of IgG1. In addition, plasma cells producing anti-Cry1Ac IgG antibodies in Peyer's patches were observed using the solid-phase enzyme-linked immunospot (ELISPOT. Cry1Ac toxin administration induced a strong immune response in serum but in the small intestinal fluids only anti-Cry1Ac IgA antibodies were detected. The data obtained in the present study confirm that the Cry1Ac protoxin is a potent immunogen able to induce a specific immune response in the mucosal tissue, which has not been observed in response to most other proteins.

  10. SU-8 photolithography on reactive plasma thin-films: coated microwells for peptide display.

    Science.gov (United States)

    Marchesan, Silvia; Easton, Christopher D; Styan, Katie E; Leech, Patrick; Gengenbach, Thomas R; Forsythe, John S; Hartley, Patrick G

    2013-08-01

    We have developed a technique to create 50μm-deep microwells coated with a reactive and robust thin film, which withstands photolithographic processing, and allows for subsequent chemical functionalisation with biological cues (i.e. peptides). First, plasma polymerisation of 1-bromopropane was used to generate a bromine-functionalised thin film (BrPP) on a substrate of silicon wafer. Second, an epoxy functionalised polymer UV photoresist, SU-8, was deposited and developed to create 50μm-deep patterned microwells that display the BrPP coating at their base. Third, amino acids or peptides were selectively attached to the bottom of the microwells through bromine displacement by an amine or thiol nucleophile. Each surface functionalisation step was monitored by XPS, AFM, and contact angle measurements. These functionalities were then used as linkers to immobilise enzymes (e.g. HRP), which retain activity at the end of the process as shown by a biochemical activity assay. Peptide promoters of cell attachment were also immobilised and their functionality was evaluated using an L929 fibroblast adhesion assay. In conclusion, this work describes an innovative combination of plasma thin film deposition and photolithography to create 50μm-deep functionalised microwells for peptide display in biological applications.

  11. Plasma physics and engineering

    CERN Document Server

    Fridman, Alexander

    2011-01-01

    Part I: Fundamentals of Plasma Physics and Plasma ChemistryPlasma in Nature, in the Laboratory, and in IndustryOccurrence of Plasma: Natural and Man MadeGas DischargesPlasma Applications, Plasmas in IndustryPlasma Applications for Environmental ControlPlasma Applications in Energy ConversionPlasma Application for Material ProcessingBreakthrough Plasma Applications in Modern TechnologyElementary Processes of Charged Species in PlasmaElementary Charged Particles in Plasma and Their Elastic and Inelastic CollisionsIonization ProcessesMechanisms of Electron Losses: The Electron-Ion RecombinationEl

  12. Miniaturized cathodic arc plasma source

    Science.gov (United States)

    Anders, Andre; MacGill, Robert A.

    2003-04-15

    A cathodic arc plasma source has an anode formed of a plurality of spaced baffles which extend beyond the active cathode surface of the cathode. With the open baffle structure of the anode, most macroparticles pass through the gaps between the baffles and reflect off the baffles out of the plasma stream that enters a filter. Thus the anode not only has an electrical function but serves as a prefilter. The cathode has a small diameter, e.g. a rod of about 1/4 inch (6.25 mm) diameter. Thus the plasma source output is well localized, even with cathode spot movement which is limited in area, so that it effectively couples into a miniaturized filter. With a small area cathode, the material eroded from the cathode needs to be replaced to maintain plasma production. Therefore, the source includes a cathode advancement or feed mechanism coupled to cathode rod. The cathode also requires a cooling mechanism. The movable cathode rod is housed in a cooled metal shield or tube which serves as both a current conductor, thus reducing ohmic heat produced in the cathode, and as the heat sink for heat generated at or near the cathode. Cooling of the cathode housing tube is done by contact with coolant at a place remote from the active cathode surface. The source is operated in pulsed mode at relatively high currents, about 1 kA. The high arc current can also be used to operate the magnetic filter. A cathodic arc plasma deposition system using this source can be used for the deposition of ultrathin amorphous hard carbon (a-C) films for the magnetic storage industry.

  13. Wind-powered asynchronous AC/DC/AC converter system. [for electric power supply regulation

    Science.gov (United States)

    Reitan, D. K.

    1973-01-01

    Two asynchronous ac/dc/ac systems are modelled that utilize wind power to drive a variable or constant hertz alternator. The first system employs a high power 60-hertz inverter tie to the large backup supply of the power company to either supplement them from wind energy, storage, or from a combination of both at a preset desired current; rectifier and inverter are identical and operate in either mode depending on the silicon control rectifier firing angle. The second system employs the same rectification but from a 60-hertz alternator arrangement; it provides mainly dc output, some sinusoidal 60-hertz from the wind bus and some high harmonic content 60-hertz from an 800-watt inverter.

  14. Three-Level AC-DC-AC Z-Source Converter Using Reduced Passive Component Count

    DEFF Research Database (Denmark)

    Loh, Poh Chiang; Gao, Feng; Tan, Pee-Chin;

    2007-01-01

    This paper presents a three-level ac-dc-ac Z-source converter with output voltage buck-boost capability. The converter is implemented by connecting a low cost front-end diode rectifier to a neutral-point-clamped inverter through a single X-shaped LC impedance network. The inverter is controlled...... to switch with a three-level output voltage, where the middle neutral potential is uniquely tapped from the star-point of a wye-connected capacitive filter placed before the front-end diode rectifier for input current filtering. Through careful control, the resulting converter can accurately produce...... the correct volt-sec average at its output, while simultaneously achieving inductive voltage boosting. More interestingly, these performance features are achieved with no increase in the number of semiconductor commutations, and hence no increase in switching losses. The proposed converter therefore offers...

  15. Equivalent circuit models for ac impedance data analysis

    Science.gov (United States)

    Danford, M. D.

    1990-01-01

    A least-squares fitting routine has been developed for the analysis of ac impedance data. It has been determined that the checking of the derived equations for a particular circuit with a commercially available electronics circuit program is essential. As a result of the investigation described, three equivalent circuit models were selected for use in the analysis of ac impedance data.

  16. A remark on Kov\\'acs' vanishing theorem

    CERN Document Server

    Fujino, Osamu

    2012-01-01

    We give an alternative proof of Kov\\'acs' vanishing theorem. Our proof is based on the standard arguments of the minimal model theory. We do not need the notion of Du Bois pairs. We reduce Kov\\'acs' vanishing theorem to the well-known relative Kawamata--Viehweg--Nadel vanishing theorem.

  17. 40 CFR Appendixes A-C to Part 403 - [Reserved

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true A Appendixes A-C to Part 403 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GENERAL PRE-TREAT-MENT REGULATIONS FOR EXIST-ING AND NEW SOURCES OF POLLUTION Appendixes A-C to Part 403 ...

  18. Flexible AC transmission systems: the state of the art

    Energy Technology Data Exchange (ETDEWEB)

    Edris, Abdel-Aty [Electric Power Research Inst., Palo Alto, CA (United States). Electric Systems Division

    1994-12-31

    Flexible AC transmission systems (FACTS) is a concept promoting the use of power electronic controllers to enhance the controllability and usable capacity of AC transmission. This paper presents the state of the art of FACTS and the status of the current projects for the application of the FACTS controllers in transmission systems. (author) 8 refs., 8 figs.

  19. Considerations for an Ac Dipole for the LHC

    CERN Document Server

    Bai, M; Fischer, W; Oddo, P; Schmickler, Hermann; Serrano, J; Jansson, A; Syphers, M; Kopp, S; Miyamoto, R

    2007-01-01

    Following successful experience at the BNL AGS, FNAL Tevatron, and CERN SPS, an AC Dipole will be adopted at the LHC for rapid measurements of ring optics. This paper describes some of the parameters of the AC dipole for the LHC, scaling from performance of the FNAL and BNL devices.

  20. Precursors of Short GRBs Registered by SPI-ACS/INTEGRAL

    Science.gov (United States)

    Minaev, P.; Pozanenko, A.

    2016-10-01

    We have searched for precursors in light curves of short gamma-ray bursts registered by SPI-ACS/INTEGRAL in 2002-2014. The portion of short bursts with precursor activity will be less than 0.4% from all short bursts registered by SPI-ACS.

  1. Scaling and universality of ac conduction in disordered solids

    DEFF Research Database (Denmark)

    Schrøder, Thomas; Dyre, Jeppe

    2000-01-01

    Recent scaling results for the ac conductivity of ionic glasses by Roling et al. [Phys. Rev. Lett. 78, 2160 (1997)] and Sidebottom [Phys. Rev. Lett. 82, 3653 (1999)] are discussed. We prove that Sidebottom's version of scaling is completely general. A new approximation to the universal ac...

  2. The topological AC effect on noncommutative phase space

    CERN Document Server

    Li, K; Li, Kang; Wang, Jianhua

    2006-01-01

    The Aharonov-Casher (AC) effect in non-commutative(NC) quantum mechanics is studied. Instead of using the star product method, we use a generalization of Bopp's shift method. After solving the Dirac equations both on noncommutative space and noncommutative phase space by the new method, we obtain the corrections to AC phase on NC space and NC phase space respectively.

  3. Operation of AC Adapters Visualized Using Light-Emitting Diodes

    Science.gov (United States)

    Regester, Jeffrey

    2016-01-01

    A bridge rectifier is a diamond-shaped configuration of diodes that serves to convert alternating current(AC) into direct current (DC). In our world of AC outlets and DC electronics, they are ubiquitous. Of course, most bridge rectifiers are built with regular diodes, not the light-emitting variety, because LEDs have a number of disadvantages. For…

  4. New switching pattern for AC/AC converters with RB-IGBTs for offshore wind parks

    OpenAIRE

    Mogstad, Anne Berit

    2008-01-01

    Offshore wind power has an increasing interest in the research community and among the politicians. Therefore it is important to find the right solutions to meet the environmental and commercial requirements to give offshore wind power a promising future. This thesis are proposing a new converter topology for offshore wind parks. Since the topology is based on DC transmission in stead of AC transmission it is better suited for use in this type of parks. All the converters are located in the w...

  5. Anode Spot Formation in Low Pressure and Temperature He Plasma

    Science.gov (United States)

    Scheiner, Brett; Barnat, Edward; Hopkins, Matthew; Baalrud, Scott; Yee, Benjamin

    2016-10-01

    When a small electrode is biased sufficiently above the plasma potential in a low temperature plasma, the electron impact ionization of neutral species near the electrode becomes significant. At neutral gas pressures of 1-100mTorr, it has been previously observed that if this ionization rate is sufficiently high, a double layer may form near the electrode. In some cases the double layer will move outward, separating a high potential plasma attached to the electrode surface from the bulk plasma. This phenomenon is known as an anode spot. A model has been developed describing the formation of anode spots based on observations from 2D particle-in-cell simulations. In this model ionization leads to the buildup of an ion rich region adjacent to the electrode, which modifies the potential structure in a way that traps electrons near the electrode surface. This leads to the formation of a quasineutral plasma near the electrode surface. When the density of this plasma is large enough, the double layer expands due to a pressure imbalance. Observations from PIC simulations were found to be consistent with time resolved measurements of the electron density from laser collision induced fluorescence, and with plasma emission measurements. This research was supported by the Office of Fusion Energy Science at the U.S. Department of Energy under contract DE-AC04-94SL85000 and by the Office of Science Graduate Student Research (SCGSR) program under Contract Number DE-AC05-06OR23100.

  6. HVDC-AC system interaction from AC harmonics. Volume 1. Harmonic impedance calculations. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Breuer, G D; Chow, J H; Lindh, C B; Miller, N W; Numrich, F H; Price, W W; Turner, A E; Whitney, R R

    1982-09-01

    Improved methods are needed to characterize ac system harmonic behavior for ac filter design for HVDC systems. The purpose of this General Electric Company RP1138 research is to evaluate the present filter design practice and to investigate methods for calculating system harmonic impedances. An overview of ac filter design for HVDC systems and a survey of literature related to filter design have been performed. Two methods for calculating system harmonic impedances have been investigated. In the measurement method, an instrumentation system for measuring system voltage and current has been assembled. Different schemes of using the measurements to calculate system harmonic impedances have been studied. In the analytical method, a procedure to include various operating conditions has been proposed. Computer programs for both methods have been prepared, and the results of the measurement and analytical methods analyzed. A conclusion of the project is that the measurement and analytical methods both provided reasonable results. There are correlations between the measured and analytical results for most harmonics, although there are discrepancies between the assumptions used in the two methods. A sensitivity approach has been proposed to further correlate the results. From the results of the analysis, it is recommended that both methods should be tested further. For the measurement method, more testing should be done to cover different system operating conditions. In the analytical method, more detailed models for representing system components should be studied. In addition, alternative statistical and sensitivity approaches should be attempted.

  7. HVDC-AC system interaction from AC harmonics. Volume 1. Harmonic impedance calculations. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Breuer, G D; Chow, J H; Lindh, C B; Miller, N W; Numrich, F H; Price, W W; Turner, A E; Whitney, R R

    1982-09-01

    Improved methods are needed to characterize ac system harmonic behavior for ac filter design for HVDC systems. The purpose of this General Electric Company RP1138 research is to evaluate the present filter design practice and to investigate methods for calculating system harmonic impedances. An overview of ac filter design for HVDC systems and a survey of literature related to filter design have been performed. Two methods for calculating system harmonic impedances have been investigated. In the measurement method, an instrumentation system for measuring system voltage and current has been assembled. Different schemes of using the measurements to calculate system harmonic impedances have been studied. In the analytical method, a procedure to include various operating conditions has been proposed. Computer programs for both methods have been prepared, and the results of the measurement and analytical methods analyzed. A conclusion of the project is that the measurement and analytical methods both provided reasonable results. There are correlations between the measured and analytical results for most harmonics, although there are discrepancies between the assumptions used in the two methods. A sensitivity approach has been proposed to further correlate the results. From the results of the analysis, it is recommended that both methods should be tested further. For the measurement method, more testing should be done to cover different system operating conditions. In the analytical method, more detailed models for representing system components should be studied. In addition, alternative statistical and sensitivity approaches should be attempted.

  8. Ac response of a coupled double quantum dot

    Institute of Scientific and Technical Information of China (English)

    Xu Jie; W.Z. Shangguan; Zhan Shi-Chang

    2005-01-01

    The effect of phase-breaking process on the ac response of a coupled double quantum dot is studied in this paper based on the nonequilibrium Green function formalism. A general expression is derived for the ac current in the presence of electron-phonon interaction. The ac conductance is numerically computed and the results are compared with those in [Anatram M P and Datts S 1995 Phys. Rev. B 51 7632]. Our results reveal that the inter-dot electron tunnelling interplays with that between dots and electron reservoirs, and contributes prominently to the ac current when inter-dot tunnelling coupling is much larger than the tunnelling coupling between dots and electron reservoirs. In addition, the phase-breaking process is found to have a significant effect on the ac transport through the coupled double dot.

  9. Characterisation of AC1: a naturally decaffeinated coffee

    Directory of Open Access Journals (Sweden)

    Luciana Benjamim Benatti

    2012-01-01

    Full Text Available We compared the biochemical characteristics of the beans of a naturally decaffeinated Arabica coffee (AC1 discovered in 2004 with those of the widely grown Brazilian Arabica cultivar "Mundo Novo" (MN. Although we observed differences during fruit development, the contents of amino acids, organic acids, chlorogenic acids, soluble sugars and trigonelline were similar in the ripe fruits of AC1 and MN. AC1 beans accumulated theobromine, and caffeine was almost entirely absent. Tests on the supply of [2-14C] adenine and enzymatic analysis of theobromine synthase and caffeine synthase in the endosperm of AC1 confirmed that, as in the leaves, caffeine synthesis is blocked during the methylation of theobromine to caffeine. The quality of the final coffee beverage obtained from AC1 was similar to that of MN.

  10. Determination for β-delayed fission probability of 230Ac

    Institute of Scientific and Technical Information of China (English)

    袁双贵; 杨维凡; 徐岩冰; 肖永厚; 罗亦孝

    2002-01-01

    The 230Ra has been produced via 232Th-2p reaction induced by 60 MeV/u 18O ion irradia-tion of natural thorium. The radium was radiochemically separated from the mixture of thorium andreaction products. Thin Ra sources in which 230Ac was got through 230Ra β- → 230Ac were pre-pared for observing fission fragments from β-delayed fission of 230Ac. The sources were exposedto the mica fission track detectors and measured by the HPGe γ detector. The precursor 230Ac wasidentified by means of observed two fission events as well as γ spectra, and the β-delayed fissionprobability of 230Ac was obtained to be (1.19±0.85) × 10-8.

  11. Estimation of the Thurstonian model for the 2-AC protocol

    DEFF Research Database (Denmark)

    Christensen, Rune Haubo Bojesen; Lee, Hye-Seong; Brockhoff, Per B.

    2012-01-01

    The 2-AC protocol is a 2-AFC protocol with a “no-difference” option and is technically identical to the paired preference test with a “no-preference” option. The Thurstonian model for the 2-AC protocol is parameterized by δ and a decision parameter τ, the estimates of which can be obtained...... by fairly simple well-known methods. In this paper we describe how standard errors of the parameters can be obtained and how exact power computations can be performed. We also show how the Thurstonian model for the 2-AC protocol is closely related to a statistical model known as a cumulative probit model....... This relationship makes it possible to extract estimates and standard errors of δ and τ from general statistical software, and furthermore, it makes it possible to combine standard regression modelling with the Thurstonian model for the 2-AC protocol. A model for replicated 2-AC data is proposed using cumulative...

  12. 单相电压型Z源AC/AC变流器电路%Single-Phase Voltage-Fed Z-Source AC/AC Converter

    Institute of Scientific and Technical Information of China (English)

    房绪鹏

    2006-01-01

    提出了一种新型AC/AC变流器电路--单相电压型Z源AC/AC变流器;介绍了其电路拓扑、工作原理、控制方法等;给出了相应的仿真和实验结果.仿真和实验证实了该电路拓扑的合理性和优越性.

  13. Glucagon-like peptide-1 and the exenatide analogue AC3174 improve cardiac function, cardiac remodeling, and survival in rats with chronic heart failure

    Directory of Open Access Journals (Sweden)

    Polizzi Clara

    2010-11-01

    Full Text Available Abstract Background Accumulating evidence suggests glucagon-like peptide-1 (GLP-1 exerts cardioprotective effects in animal models of myocardial infarction (MI. We hypothesized that chronic treatment with GLP-1 or the exenatide analog AC3174 would improve cardiac function, cardiac remodeling, insulin sensitivity, and exercise capacity (EC in rats with MI-induced chronic heart failure (CHF caused by coronary artery ligation. Methods Two weeks post-MI, male Sprague-Dawley rats were treated with GLP-1 (2.5 or 25 pmol/kg/min, AC3174 (1.7 or 5 pmol/kg/min or vehicle via subcutaneous infusion for 11 weeks. Cardiac function and morphology were assessed by echocardiography during treatment. Metabolic, hemodynamic, exercise-capacity, and body composition measurements were made at study end. Results Compared with vehicle-treated rats with CHF, GLP-1 or AC3174 significantly improved cardiac function, including left ventricular (LV ejection fraction, and end diastolic pressure. Cardiac dimensions also improved as evidenced by reduced LV end diastolic and systolic volumes and reduced left atrial volume. Vehicle-treated CHF rats exhibited fasting hyperglycemia and hyperinsulinemia. In contrast, GLP-1 or AC3174 normalized fasting plasma insulin and glucose levels. GLP-1 or AC3174 also significantly reduced body fat and fluid mass and improved exercise capacity and respiratory efficiency. Four of 16 vehicle control CHF rats died during the study compared with 1 of 44 rats treated with GLP-1 or AC3174. The cellular mechanism by which GLP-1 or AC3174 exert cardioprotective effects appears unrelated to changes in GLUT1 or GLUT4 translocation or expression. Conclusions Chronic treatment with either GLP-1 or AC3174 showed promising cardioprotective effects in a rat model of CHF. Hence, GLP-1 receptor agonists may represent a novel approach for the treatment of patients with CHF or cardiovascular disease associated with type 2 diabetes.

  14. 40 CFR 86.162-00 - Approval of alternative air conditioning test simulations and descriptions of AC1 and AC2.

    Science.gov (United States)

    2010-07-01

    ... Procedures § 86.162-00 Approval of alternative air conditioning test simulations and descriptions of AC1 and AC2. The alternative air conditioning test procedures AC1 and AC2 are approved by the Administrator... requirements of paragraph (a) of this section and meet the requirements of § 86.163-00. Air conditioning tests...

  15. An Ac transposon system based on maize chromosome 4S for isolating long-distance-transposed Ac tags in the maize genome.

    Science.gov (United States)

    Wang, Fei; Li, Zhaoying; Fan, Jun; Li, Pengfei; Hu, Wei; Wang, Gang; Xu, Zhengkai; Song, Rentao

    2010-12-01

    Transposon tagging is an important tool for gene isolation and functional studies. In maize, several transposon-tagging systems have been developed, mostly using Activator/Dissociation (Ac/Ds) and Mutator systems. Here, we establish another Ac-based transposon system with the donor Ac tightly linked with sugary1 (su1) on maize chromosome 4S. Newly transposed Ac (tr-Acs) were detected based on a negative dosage effect, and long-distance-transposed Ac events were identified and isolated from the donor Ac by a simple backcross scheme. In this study, we identified 208 independent long-distance-transposed Ac lines. Thirty-one flanking sequences of these tr-Acs were isolated and localized in the maize genome. As found in previous studies, the tr-Acs preferentially inserted into genic sequences. The distribution of tr-Acs is not random. In our study, the tr-Acs preferentially transposed into chromosomes 1, 2, 9 and 10. We discuss the preferential distribution of tr-Acs from Ac systems. Our system is complementary to two other Ac-based regional-mutagenesis systems in maize, and the combined use of these systems will achieve an even and high-density distribution of Ac elements throughout the maize genome for functional-genomics studies.

  16. Safe-commutation principle for direct single-phase AC-AC converters for use in audio power amplification

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2004-01-01

    This paper presents an alternative safe commutation principle for a single phase bidirectional bridge, for use in the new generation of direct single-stage AC-AC audio power amplifiers. As compared with the bridge commutation with load current or source voltage sensing, in this approach...

  17. Safe-commutation principle for direct single-phase AC-AC converters for use in audio power amplification

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2004-01-01

    This paper presents an alternative safe commutation principle for a single phase bidirectional bridge, for use in the new generation of direct single-stage AC-AC audio power amplifiers. As compared with the bridge commutation with load current or source voltage sensing, in this approach...

  18. Magnetoresistive waves in plasmas

    Science.gov (United States)

    Felber, F. S.; Hunter, R. O., Jr.; Pereira, N. R.; Tajima, T.

    1982-10-01

    The self-generated magnetic field of a current diffusing into a plasma between conductors can magnetically insulate the plasma. Propagation of magnetoresistive waves in plasmas is analyzed. Applications to plasma opening switches are discussed.

  19. The complete Ac/Ds transposon family of maize.

    Science.gov (United States)

    Du, Chunguang; Hoffman, Andrew; He, Limei; Caronna, Jason; Dooner, Hugo K

    2011-12-01

    The nonautonomous maize Ds transposons can only move in the presence of the autonomous element Ac. They comprise a heterogeneous group that share 11-bp terminal inverted repeats (TIRs) and some subterminal repeats, but vary greatly in size and composition. Three classes of Ds elements can cause mutations: Ds-del, internal deletions of the 4.6-kb Ac element; Ds1, ~400-bp in size and sharing little homology with Ac, and Ds2, variably-sized elements containing about 0.5 kb from the Ac termini and unrelated internal sequences. Here, we analyze the entire complement of Ds-related sequences in the genome of the inbred B73 and ask whether additional classes of Ds-like (Ds-l) elements, not uncovered genetically, are mobilized by Ac. We also compare the makeup of Ds-related sequences in two maize inbreds of different origin. We found 903 elements with 11-bp Ac/Ds TIRs flanked by 8-bp target site duplications. Three resemble Ac, but carry small rearrangements. The others are much shorter, once extraneous insertions are removed. There are 331 Ds1 and 39 Ds2 elements, many of which are likely mobilized by Ac, and two novel classes of Ds-l elements. Ds-l3 elements lack subterminal homology with Ac, but carry transposase gene fragments, and represent decaying Ac elements. There are 44 such elements in B73. Ds-l4 elements share little similarity with Ac outside of the 11-bp TIR, have a modal length of ~1 kb, and carry filler DNA which, in a few cases, could be matched to gene fragments. Most Ds-related elements in B73 (486/903) fall in this class. None of the Ds-l elements tested responded to Ac. Only half of Ds insertion sites examined are shared between the inbreds B73 and W22. The majority of Ds-related sequences in maize correspond to Ds-l elements that do not transpose in the presence of Ac. Unlike actively transposing elements, many Ds-l elements are inserted in repetitive DNA, where they probably become methylated and begin to decay. The filler DNA present in most elements

  20. Electrosurgical plasmas

    Science.gov (United States)

    Stalder, Kenneth R.; McMillen, Donald F.; Woloszko, Jean

    2005-06-01

    Electrosurgical medical devices based on repetitively pulsed nonequilibrium micron-scale to millimetre-scale plasma discharges in saline solutions are described. The formation of vapour layers (bubbles) around active electrodes appears to be a common feature at moderate (<300 V rms) voltages, and dissociation, excitation and ionization of the vapour in these bubbles produces chemical conditions that are thought to be the source of beneficial tissue removal and treatment. Experimental data are discussed, as are the results of modelling efforts of the plasma chemistry. Hydroxyl radicals, hydrogen atoms and other species are observed spectroscopically and their interactions with collagen, a common component of tissue encountered in surgical situations, are considered. Several pathways by which hydroxyl radicals interacting with collagen can lead to tissue removal are discussed.

  1. Electrosurgical plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Stalder, Kenneth R; McMillen, Donald F; Woloszko, Jean [ArthroCare Corp., Sunnyvale, CA 94085-3523 (United States)

    2005-06-07

    Electrosurgical medical devices based on repetitively pulsed nonequilibrium micron-scale to millimetre-scale plasma discharges in saline solutions are described. The formation of vapour layers (bubbles) around active electrodes appears to be a common feature at moderate (<300 V rms) voltages, and dissociation, excitation and ionization of the vapour in these bubbles produces chemical conditions that are thought to be the source of beneficial tissue removal and treatment. Experimental data are discussed, as are the results of modelling efforts of the plasma chemistry. Hydroxyl radicals, hydrogen atoms and other species are observed spectroscopically and their interactions with collagen, a common component of tissue encountered in surgical situations, are considered. Several pathways by which hydroxyl radicals interacting with collagen can lead to tissue removal are discussed.

  2. Overview of plasma technology used in medicine

    Science.gov (United States)

    Ryan, Thomas P.; Stalder, Kenneth R.; Woloszko, Jean

    2013-02-01

    Plasma Medicine is a growing field that is having an impact in several important areas in therapeutic patient care, combining plasma physics, biology, and clinical medicine. Historically, plasmas in medicine were used in electrosurgery for cautery and non-contact hemostasis. Presently, non-thermal plasmas have attained widespread use in medicine due to their effectiveness and compatibility with biological systems. The paper will give a general overview of how low temperature, non-equilibrium, gas plasmas operate, both from physics and biology perspectives. Plasma is commonly described as the fourth state of matter and is typically comprised of charged species, active molecules and atoms, as well as a source of UV and photons. The most active areas of plasma technology applications are in wound treatment; tissue regeneration; inactivation of pathogens, including biofilms; treating skin diseases; and sterilization. There are several means of generating plasmas for use in medical applications, including plasma jets, dielectric barrier discharges, capacitively or inductively coupled discharges, or microplasmas. These systems overcome the former constraints of high vacuum, high power requirements and bulky systems, into systems that use room air and other gases and liquids at low temperature, low power, and hand-held operation at atmospheric pressure. Systems will be discussed using a variety of energy sources: pulsed DC, AC, microwave and radiofrequency, as well as the range of frequency, pulse duration, and gas combinations in an air environment. The ionic clouds and reactive species will be covered in terms of effects on biological systems. Lastly, several commercial products will be overviewed in light of the technology utilized, health care problems being solved, and clinical trial results.

  3. Plasma physics

    CERN Document Server

    Cairns, R A

    1985-01-01

    This book is intended as an introduction to plasma physics at a level suitable for advanced undergraduates or beginning postgraduate students in physics, applied mathematics or astrophysics. The main prerequisite is a knowledge of electromagnetism and of the associated mathematics of vector calculus. SI units are used throughout. There is still a tendency amongst some plasma physics researchers to· cling to C.g.S. units, but it is the author's view that universal adoption of SI units, which have been the internationally agreed standard since 1960, is to be encouraged. After a short introductory chapter, the basic properties of a plasma con­ cerning particle orbits, fluid theory, Coulomb collisions and waves are set out in Chapters 2-5, with illustrations drawn from problems in nuclear fusion research and space physics. The emphasis is on the essential physics involved and (he theoretical and mathematical approach has been kept as simple and intuitive as possible. An attempt has been made to draw attention t...

  4. Novel polymer coatings based on plasma polymerized 2-methoxyethyl acrylate

    DEFF Research Database (Denmark)

    Wu, Zhenning; Jiang, Juan; Benter, Maike

    2008-01-01

    plasma system[4]. The system named SoftPlasma™ is equipped with unique three-phase pulsed AC voltage. Low energy plasma polymerization has almost no thermal load for sensitive polymer materials[5]. Plasma polymerized coatings are highly cross-linked, pin-hole free and provide hydrophilic or hydrophobic...... properties[4-6]. We have exploited these possibilities and prepared plasma polymerized 2-methoxyethyl acrylate (PPMEA) coatings on various polymer substrates. The PPMEA coatings were optimized using various plasma polymerization conditions and characterized by X-ray photoelectron spectroscopy......, Fouriertransform infrared spectroscopy, Atomic force spectroscopy and Water contact-angle measurements. The microstructures ofPPMEA coatings with different thicknesses were also studied. For practical applications in mind, the coating stability was tested in different media (air, water, acetone, phosphate...

  5. Plasma pharmacy - physical plasma in pharmaceutical applications.

    Science.gov (United States)

    von Woedtke, Th; Haertel, B; Weltmann, K-D; Lindequist, U

    2013-07-01

    During the last years the use of physical plasma for medical applications has grown rapidly. A multitude of findings about plasma-cell and plasma-tissue interactions and its possible use in therapy have been provided. One of the key findings of plasma medical basic research is that several biological effects do not result from direct plasma-cell or plasma-tissue interaction but are mediated by liquids. Above all, it was demonstrated that simple liquids like water or physiological saline, are antimicrobially active after treatment by atmospheric pressure plasma and that these effects are attributable to the generation of different low-molecular reactive species. Besides, it could be shown that plasma treatment leads to the stimulation of specific aspects of cell metabolism and to a transient and reversible increase of diffusion properties of biological barriers. All these results gave rise to think about another new and innovative field of medical plasma application. In contrast to plasma medicine, which means the direct use of plasmas on or in the living organism for direct therapeutic purposes, this field - as a specific field of medical plasma application - is called plasma pharmacy. Based on the present state of knowledge, most promising application fields of plasma pharmacy might be: plasma-based generation of biologically active liquids; plasma-based preparation, optimization, or stabilization of - mainly liquid - pharmaceutical preparations; support of drug transport across biological barriers; plasma-based stimulation of biotechnological processes.

  6. Measurement of AC loss of superconductors by vaporizing method

    Energy Technology Data Exchange (ETDEWEB)

    Wakabayashi, Hiroshi; Isono, Takaaki; Matsui, Kunihiro; Fujisaki, Reishi; Nunoya, Yoshihiko; Koizumi, Norikiyo; Takahashi, Yoshikazu; Tsuji, Hiroshi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    1995-07-01

    In Japan Atomic Energy Research Institute, the development of superconducting pulse conductors for next period nuclear fusion reactors has been carried out. For these conductors, the rated current of 46 kA and the rated magnetic field of 13T are demanded. When the pulse excitation of superconductors is carried out, AC loss arises, and the temperature of the superconductors rises, and when it exceeds a certain value, the superconducting state cannot be maintained. Therefore, the AC loss of pulse conductors must be limited to a low value. It is difficult to evaluate the AC loss of superconductors by calculation, therefore, it is evaluated by actual measurement. There are magnetizing method and vaporizing method for measuring the AC loss. This time, the equipment for measuring the AC loss of 40 kA class superconductors by vaporizing method which measures the helium gas quantity vaporizing at the time of AC loss occurrence was designed and manufactured for the first time. The method of measuring the AC loss, the structure of the measuring equipment, the helium gas recovering part and the measuring part, the countermeasures for preventing helium gas leakage, the resistance heater for calibration, and the results of measurement are reported. (K.I.)

  7. Faint Galaxies in deep ACS observations

    CERN Document Server

    Benítez, N; Bouwens, R; Menanteau, F; Blakeslee, J P; Gronwall, C; Illingworth, G D; Meurer, G; Broadhurst, T J; Clampin, M; Franx, M; Hartig, G F; Magee, D; Sirianni, M; Ardila, D R; Bartko, F; Brown, R A; Burrows, C J; Cheng, E S; Cross, N J G; Feldman, P D; Golimowski, D A; Infante, L; Kimble, R A; Krist, J E; Lesser, M P; Levay, Z G; Martel, A R; Miley, G K; Postman, M; Rosati, P; Sparks, W B; Tran, H D; Tsvetanov, Z I; Zheng, R L

    2003-01-01

    We present the analysis of the faint galaxy population in the Advanced Camera for Surveys (ACS) Early Release Observation fields VV 29 (UGC 10214) and NGC 4676. Here we attempt to thoroughly consider all aspects relevant for faint galaxy counting and photometry, developing methods which are based on public software and that are easily reproducible by other astronomers. Using simulations we determine the best SExtractor parameters for the detection of faint galaxies in deep HST observations, paying special attention to the issue of deblending, which significantly affects the normalization and shape of the number count distribution. We confirm, as claimed by Bernstein, Freedman and Madore (2002), that Kron-like magnitudes, such as the ones generated by SExtractor, can miss more than half of the light of faint galaxies, what dramatically affects the slope of the number counts. We present catalogs for the VV 29 and NGC 4676 fields with photometry in the g,V and I bands. We also show that combining the bayesian so...

  8. AC Impedance Behaviour of Black Diamond Films

    Institute of Scientific and Technical Information of China (English)

    Haitao YE; Olivier GAUDIN; Richard B.JACKMAN

    2005-01-01

    The first measurement of impedance on free-standing diamond films from 0.1 Hz to 10 MHz up to 300℃ were reported. A wide range of chemical vapour deposition (CVD) materials were investigated, but here we concentrate are well fitted to a RC parallel circuit model and the equivalent resistance and capacitance for the diamond films have been estimated using the Zview curve fitting. The results show only one single semicircle response at each temperature measured. It was found that the resistance decreases from 62 MΩ at room temperature to 4 kΩ at300℃, with an activation energy around 0.51 eV. The equivalent capacitance is maintained at the level of 100 pF up to 300℃ suggesting that the diamond grain boundaries are dominating the conduction. At 400℃, the impedance at low frequencies shows a linear tail, which can be explained that the AC polarization of diamond/Au interface occurs.

  9. Neurinoma central do nervo acústico

    Directory of Open Access Journals (Sweden)

    Paulo Pinto Pupo

    1950-03-01

    Full Text Available O autor apresenta o caso de uma paciente com 45 anos, com hipertensão arterial, queixando-se de tonturas e surdez progressiva à esquerda que, ao exame neurológico, apresentava síndrome protuberancial, com hemi-anestesia táctil e dolorosa à direita respeitando a face, hemiparesia direita, ataxia de tipo sensitivo nos membros da direita, paralisia facial de tipo periférico, hipoacusia, paresia de motor ocular externo à esquerda, síndrome vertiginosa e nistagmo horizontal ao olhar para a direita. À necrópsia foi encontrado um tumor na hemicalota protuberancial esquerda e foco malácico adjacente, secundário a distúrbio circulatório. O tumor, intimamente dependente das raízes intraprotuberanciais do nervo acústico, se apresentava com as características histológicas dos neurinomas. Além dessas particularidades, a lesão do feixe central da calota e conseqüente degeneração "hipertrófica" da oliva bulbar constituem outro aspecto de grande interêsse dêste caso.

  10. Analysis of Input and Output Ripples of PWM AC Choppers

    Directory of Open Access Journals (Sweden)

    Pekik Argo Dahono

    2008-11-01

    Full Text Available This paper presents an analysis of input and output ripples of PWM AC choppers. Expressions of input and output current and voltage ripples of single-phase PWM AC choppers are first derived. The derived expressions are then extended to three-phase PWM AC choppers. As input current and output voltage ripples specification alone cannot be used to determine the unique values of inductance and capacitance of the LC filters, an additional criterion based on the minimum reactive power is proposed. Experimental results are included in this paper to show the validity of the proposed analysis method.

  11. Recurrent Security Gaps In 802.11ac Routers

    OpenAIRE

    Mohammed Farik; ABM Shawkat Ali

    2015-01-01

    Abstract In comparison to earlier IEEE 802.11 standard abgn routers todays popular 802.11ac standard routers have enhanced security. However 802.11ac router still has major security vulnerabilities. The novelty of this paper is that we not only highlight multiple security vulnerabilities in 802.11ac router technologies that still have not been secured since the earlier standards but also present some new ideas with solutions. We believe that our line of thoughts on security vulnerabilities ga...

  12. An Improved AC-BM Algorithm for Monitoring Watch List

    Directory of Open Access Journals (Sweden)

    Mo Yiwen

    2013-07-01

    Full Text Available With the expanding of database of the watch list of anti-money laundering, improving the speed in matching between the watch list and the database of account holders and clients’ transaction is especially important. This paper proposes an improved AC-BM Algorithm, a matching algorithm of subsection, to improve the speed of matching. Experiment results show the time performance of the improved algorithm is better than traditional BM algorithm, AC algorithm and the AC-BM algorithm. It can improve the efficiency of on-line monitoring of anti-money laundering.  

  13. Cyclotron production of Ac-225 for targeted alpha therapy.

    Science.gov (United States)

    Apostolidis, C; Molinet, R; McGinley, J; Abbas, K; Möllenbeck, J; Morgenstern, A

    2005-03-01

    The feasibility of producing Ac-225 by proton irradiation of Ra-226 in a cyclotron through the reaction Ra-226(p,2n)Ac-225 has been experimentally demonstrated for the first time. Proton energies were varied from 8.8 to 24.8 MeV and cross-sections were determined by radiochemical analysis of reaction yields. Maximum yields were reached at incident proton energies of 16.8 MeV. Radiochemical separation of Ac-225 from the irradiated target yielded a product suitable for targeted alpha therapy of cancer.

  14. Advanced DC/AC inverters applications in renewable energy

    CERN Document Server

    Luo, Fang Lin

    2013-01-01

    DC/AC inversion technology is of vital importance for industrial applications, including electrical vehicles and renewable energy systems, which require a large number of inverters. In recent years, inversion technology has developed rapidly, with new topologies improving the power factor and increasing power efficiency. Proposing many novel approaches, Advanced DC/AC Inverters: Applications in Renewable Energy describes advanced DC/AC inverters that can be used for renewable energy systems. The book introduces more than 100 topologies of advanced inverters originally developed by the authors,

  15. Formation of Anode Spots in Low Pressure Plasmas

    Science.gov (United States)

    Scheiner, Brett; Barnat, Edward; Hopkins, Matthew; Baalrud, Scott; Yee, Benjamin

    2016-09-01

    When small electrodes are biased sufficiently above the plasma potential, the rate of electron impact ionization of neutrals can increase near the electrode. At neutral gas pressures of 1-100mTorr, it has been previously observed that if this ionization rate is sufficiently high a double layer forms near the electrode. Sometimes this double layer will move outward, separating a high potential plasma, attached to the electrode surface, from the bulk plasma. This phenomenon is known as an anode spot or fireball. Using observations from the first 2D particle-in-cell simulations of the anode spot, a model has been developed describing this formation process. In this model ionization leads to the buildup of an ion rich region adjacent to the electrode, which modifies the potential structure in a way that traps electrons near the electrode surface. This establishes a quasineutral plasma near the electrode. When the density of this plasma is large enough, a pressure imbalance across the double layer leads to its expansion from the electrode surface. Observations from simulations, along with the presented model, are found to be consistent with time resolved measurements of the electron density from laser collision induced fluorescence, and with plasma emission measurements. This research was supported by the Office of Fusion Energy Science at the U.S. Department of Energy under contract DE-AC04-94SL85000 and by the Office of Science Graduate Student Research (SCGSR) program under Contract Number DE-AC05-06OR23100.

  16. An experimental study of icing control using DBD plasma actuator

    Science.gov (United States)

    Cai, Jinsheng; Tian, Yongqiang; Meng, Xuanshi; Han, Xuzhao; Zhang, Duo; Hu, Haiyang

    2017-08-01

    Ice accretion on aircraft or wind turbine has been widely recognized as a big safety threat in the past decades. This study aims to develop a new approach for icing control using an AC-DBD plasma actuator. The experiments of icing control (i.e., anti-/de-icing) on a cylinder model were conducted in an icing wind tunnel with controlled wind speed (i.e., 15 m/s) and temperature (i.e., -10°C). A digital camera was used to record the dynamic processes of plasma anti-icing and de-icing whilst an infrared imaging system was utilized to map the surface temperature variations during the anti-/de-icing processes. It was found that the AC-DBD plasma actuator is very effective in both anti-icing and de-icing operations. While no ice formation was observed when the plasma actuator served as an anti-icing device, a complete removal of the ice layer with a thickness of 5 mm was achieved by activating the plasma actuator for ˜150 s. Such information demonstrated the feasibility of plasma anti-/de-icing, which could potentially provide more effective and safer icing mitigation strategies.

  17. Single-Phase Four Switch Z-Source AC-AC Converters%单相四开关Z源AC-AC变换器

    Institute of Scientific and Technical Information of China (English)

    汤雨; 谢少军; 张超华

    2007-01-01

    提出了一种单相四开关Z源AC-AC变换器,它包括电压型与电流型两类.与传统脉宽调制AC-AC变换器相比,它具有如下特点:输出电压范围宽且可升可降,输出电压与输入电压可同相或反相,冲击和谐波电流小,可靠性高.针对AC-AC变换器中固有的开关管换流问题,提出了一种适用于单相四开关Z源AC-AC变换器的换流方案,无需外加缓冲吸收电路即可实现开关管的安全换流.以电压型单相四开关Z源AC-AC变换器为例,对其进行了理论分析、仿真和原理试验研究.实验结果证实了Z源变换器的特性及换流方案的可行性.

  18. ACS Algorithm in Discrete Ordinates for Pressure Vessel Dosimetry

    Directory of Open Access Journals (Sweden)

    Walters William

    2016-01-01

    Full Text Available The Adaptive Collision Source (ACS method can solve the Linear Boltzmann Equation (LBE more efficiently by adaptation of the angular quadrature order. This is similar to, and essentially an extension of, the first collision source method. Previously, the ACS methodology has been implemented into the TITAN discrete ordinates code, and has shown speedups of 2–4 on a simple test problem, with very little loss of accuracy (within a provided adaptive tolerance. This work examines the use of the ACS method for a more realistic problem: pressure vessel dosimetry with the VENUS-2 MOX-fuelled reactor dosimetry benchmark. The ACS method proved to be able to obtain accurate results while being approximately twice as efficient as using a constant quadrature in a standard source iteration scheme.

  19. Fabrication of alumina films with laminated structures by ac anodization

    Directory of Open Access Journals (Sweden)

    Hiroyo Segawa

    2014-01-01

    Full Text Available Anodization techniques by alternating current (ac are introduced in this review. By using ac anodization, laminated alumina films are fabricated. Different types of alumina films consisting of 50–200 nm layers were obtained by varying both the ac power supply and the electrolyte. The total film thickness increased with an increase in the total charge transferred. The thickness of the individual layers increased with the ac voltage; however, the anodization time had little effect on the film thickness. The laminated alumina films resembled the nacre structure of shells, and the different morphologies exhibited by bivalves and spiral shells could be replicated by controlling the rate of increase of the applied potentials.

  20. A hybrid electromechanical solid state switch for ac power control

    Science.gov (United States)

    1972-01-01

    Bidirectional thyristor coupled to a series of actuator driven electromechanical contacts generates hybrid electromechanical solid state switch for ac power control. Device is useful in power control applications where zero crossover switching is required.

  1. EHV AC undergrounding electrical power performance and planning

    CERN Document Server

    Benato, Roberto

    2014-01-01

    Analytical methods of cable performance in EHV AC electrical power are discussed in this comprehensive reference. Descriptions of energization, power quality, cable safety constraints and more, guide readers in cable planning and power network operations.

  2. Hydrolysis of polycarbonate catalyzed by ionic liquid [Bmim][Ac].

    Science.gov (United States)

    Song, Xiuyan; Liu, Fusheng; Li, Lei; Yang, Xuequn; Yu, Shitao; Ge, Xiaoping

    2013-01-15

    Hydrolysis of polycarbonate (PC) was studied using ionic liquid 1-butyl-3-methylimidazolium acetate ([Bmim][Ac]) as a catalyst. The influences of temperature, time, water dosage and [Bmim][Ac] dosage on the hydrolysis reaction were examined. Under the conditions of temperature 140°C, reaction time 3.0 h, m([Bmim][Ac]):m(PC)=1.5:1 and m(H(2)O):m(PC)=0.35:1, the conversion of PC was nearly 100% and the yield of bisphenol A (BPA) was over 96%. The ionic liquid could be reused up to 6 times without apparent decrease in the conversion of PC and yield of BPA. The kinetics of the reaction was also investigated. The results showed that the hydrolysis of PC in [Bmim][Ac] was a first-order kinetic reaction with an activation energy of 228 kJ/mol.

  3. Methanolysis of polycarbonate catalysed by ionic liquid [Bmim][Ac].

    Science.gov (United States)

    Liu, Fusheng; Li, Lei; Yu, Shitao; Lv, Zhiguo; Ge, Xiaoping

    2011-05-15

    The methanolysis of polycarbonate (PC) was studied using ionic liquid [Bmim][Ac] as a catalyst. The effects of temperature, time, methanol dosage and [Bmim][Ac] dosage on the methanolysis reaction were examined. It was shown that the conversion of PC was nearly 100%, and the yield of bisphenol A (BPA) was over 95% under the following conditions: m([Bmim][Ac]):m(PC) = 0.75:1;m(methanol):m(PC) = 0.75:1; a reaction temperature of 90 °C and a total time of 2.5h. The ionic liquid could be reused up to 6 times with no apparent decrease in the conversion of PC and yield of BPA. The kinetics of the reaction was also investigated. The results indicated that the methanolysis of PC in [Bmim][Ac] was a first-order kinetic reaction with an activation energy of 167 kJ/mol.

  4. PREVENTION AND CONTROL OF TUBERCULOSIS *A.C. Okoh ...

    African Journals Online (AJOL)

    drclement

    *A.C. Okoh. Department of Community Health, University of Teaching Hospital Benin City,. Nigeria ... Organization. (WHO) ... Control is the reduction of the prevalence ... behavioural changes, especially in ... stimulate an acquired resistance to.

  5. Alternating current(AC) corrosion analyzed by electrochemical impedance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Tae Hyun; Kim, Dae Kyeong; Bae, Jeong Hyo; Lee, Hyun Goo; Lee, Sung Jin [Korea Electrotechnology Research Institute, Changwon (Korea, Republic of)

    2002-12-15

    So far, many research results on AC corrosion have been reported but each one is not consistent with another. In order to understand the characteristics and factors affecting on AC corrosion, Electrochemical impedance spectroscopy (E.I.S) was used and changes in kinetics and surface properties was analyzed. Generally, E.I.S. test has been used mainly for the diagnosis of the concrete corrosion and coating material. However, considering the outstanding functions of E.I.S. test, it can be adopted as a good method to study AC corrosion. Electrolyte resistance (R{sub sol}), double layer capacitance (C{sub dl}) and polarization resistance (R{sub p}) are the basic circuit elements. Using the model which is consist of these basic elements, various results of E.I.S. test can be interpreted. And through this method the mechanism and characteristics of AC corrosion can be explained

  6. American Community Survey (ACS) 5-Year Estimates for Coastal Geographies

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The American Community Survey (ACS) is an ongoing statistical survey that samples a small percentage of the population every year. These data have been apportioned...

  7. A precursor of β-delayed fission:230Ac

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The 230Ra has been produced via multinucleon transfer and dissipativefragmentation of heavy target in the 60 MeV/u 18O ion reaction with natural thorium.The radium was radiochemically separated from irradiated thorium targets. 230Acwas obtained by 230Ra β-→ 230Ac. Thin Ra sources were prepared for observing fissionfragments from β-delayed fission of 230Ac. The sources were exposed to the micafission track detectors and measured by a HPGe γ detector. The two fission eventswere obtained and could been assigned to theβ-delayed fission of 230Ac. The β-delayedfission probability of 230Ac was determined to be (1.19+0.85) × 10-8.

  8. A Switched Capacitor Based AC/DC Resonant Converter for High Frequency AC Power Generation

    Directory of Open Access Journals (Sweden)

    Cuidong Xu

    2015-09-01

    Full Text Available A switched capacitor based AC-DC resonant power converter is proposed for high frequency power generation output conversion. This converter is suitable for small scale, high frequency wind power generation. It has a high conversion ratio to provide a step down from high voltage to low voltage for easy use. The voltage conversion ratio of conventional switched capacitor power converters is fixed to n, 1/n or −1/n (n is the switched capacitor cell. In this paper, A circuit which can provide n, 1/n and 2n/m of the voltage conversion ratio is presented (n is stepping up the switched capacitor cell, m is stepping down the switching capacitor cell. The conversion ratio can be changed greatly by using only two switches. A resonant tank is used to assist in zero current switching, and hence the current spike, which usually exists in a classical switching switched capacitor converter, can be eliminated. Both easy operation and efficiency are possible. Principles of operation, computer simulations and experimental results of the proposed circuit are presented. General analysis and design methods are given. The experimental result verifies the theoretical analysis of high frequency AC power generation.

  9. Simulation of the Relaxation Potential Profile of an ac-dc-ac Test

    Directory of Open Access Journals (Sweden)

    Kerry N. Allahar

    2014-01-01

    Full Text Available The relaxation period of the accelerated ac-dc-ac test for coatings is associated with the transient electrochemistry that occurs when the immersed coated system is allowed to return to a stable open-circuit condition after being subjected to a cathodic potential. A mathematical model of the transient electrochemistry that occurs during this relaxation period is presented for coated aluminum. Expressions for the corrosion potential and corrosion current as functions of the local pH at the metal-coating interface were developed using reported experimental results. These expressions enabled the simulation of the transient electrochemistry under the constraint of balanced anodic and cathodic current densities. Regression of the transient relaxation potential profiles to exponential decay functions provided time-constant characterization of the profiles. Simulated results are presented that demonstrate the influences of the coating's porosity and thickness, the applied dc potential and the metal-coating interface condition on the time-constants associated with the relaxation profile. Interpretation of experimentally reported relaxation potential profiles supported the analysis of the simulated results.

  10. Polymerisation of ethene and propene with heterogeneous Ziegler Natta catalysts. Transient comonomer effects on polymerisation kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Wester, T.S.

    1994-12-01

    This thesis investigates the immediate effect of a series of comonomers on the active center and the polymerization kinetics by using a polymerization apparatus which allows detailed continuous monitoring of the monomer consumption and by injecting the comonomers during polymerization. The resulting polymers are characterised by differential scanning calorimetry, infrared spectroscopy and extraction with heptane. Two catalysts are used: a ball-milled catalyst containing ethyl benzoate and a precipitated catalyst containing di-iso-butyl phthalate, both MgCl{sub 2} supported TiCl{sub 4} catalysts activated by triethylaluminium. The polymerizations are performed in heptane slurry at 50 {sup o}C and 1 atmosphere. The effect of a comonomer injection can be divided into four stages: The first and the second stage, i.e. the injection shock and the injection peak, are injection artefacts. The third stage is the immediate chemical response to the comonomer. The fourth stage is the long term response of the system to the comonomer and may be of a physical or a chemical nature. Propene injections cause a permanent increase in the polymerization rate of ethene. Propene is incorporated into the polyethene. Ethene injections are followed by a temporary increase in the polymerization rate of propene, and seems to initiate new active sites rather than reactivate dormant sites. Cyclopentene and several other substances adsorb on the active sites which are polymerizing propene but do not seem to incorporate into the polypropene. The activity decrease in the polymerization rates of propene and ethene after injection of a comonomer are given. 109 refs., 68 figs., 57 tabs.

  11. The density and velocity of plasma bullets propagating along one dielectric tube

    Directory of Open Access Journals (Sweden)

    Longfei Ji

    2015-08-01

    Full Text Available This study shows that the propagation of plasma bullets along one dielectric tube is strongly affected by many discharge parameters, such as the waveform of applied voltage (AC or pulsed DC, peak voltage, He flow rate, and the frequency of AC voltage. Analysis indicates that the density and velocity of plasma bullets are mainly determined by the electric field at the front of plasma bullets. These discharge parameters may significantly influence the distribution of plasma potential along the tube, thus control the electric field at the front of plasma bullets and their propagation. An increase in the pulsed DC voltage with its rise time of <40-50 ns can lead to an obvious improvement in the electric field at the front of plasma bullets, resulting in generation of a plasma in the high density gas and a fast propagation of plasma bullets. He flowing through the tube can contribute to the surface diffusion of charged species, and greatly increase the electric field at the front of plasma bullets. During the propagation of plasma bullets, their density is decreased due to the surface recombination of charged species, such as electrons and ions.

  12. Diffusive Suppression of AC-Stark Shifts in Atomic Magnetometers

    CERN Document Server

    Sulai, I A; Kauer, M; Smetana, G S; Wakai, R T; Walker, T G

    2012-01-01

    In atomic magnetometers, the vector AC-Stark shift associated with circularly polarized light generates spatially varying effective magnetic fields which limit the magnetometer response and serve as sources of noise. We describe a scheme whereby optically pumping a small sub-volume of the magnetometer cell and relying on diffusion to transport polarized atoms allows a magnetometer to be operated with minimal sensitivity to the AC-Stark field.

  13. Antifriction coatings based on a-C for biomedicine applications

    Science.gov (United States)

    Yurjev, Y. N.; Kiseleva, D. V.; Zaitcev, D. A.; Sidelev, D. V.; Korneva, O. S.

    2016-01-01

    This article reports on the investigation of mechanical properties of carbon films deposited by dual magnetron sputtering system with closed and mirror magnetic field. There is shown that a-C films with predominantly sp2-phase have relatively high hardness (up to 20 GPa) and low friction index (∼0.01). The influence of magnetic field on friction index is determined. The analysis of experimental data shows the obtained a-C samples can be used for biomedicine applications.

  14. Adiabaticity of the ramping process of an ac dipole

    Directory of Open Access Journals (Sweden)

    R. Tomás

    2005-02-01

    Full Text Available ac dipoles in accelerators are used to excite coherent betatron oscillations at a drive frequency close to the tune. If the excitation amplitude is slowly increased to the desired value and slowly decreased back to zero there is no significant emittance growth. The aim of this article is to study the adiabaticity of the ramping process of an ac dipole as a function of the different parameters involved.

  15. Development of the Field of Flexible AC Transmission Systems (FACTS)

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@ Theoretical and technological development of large capacity power electronics and flexible AC transmission systems are one of the most important projects developed by Tsinghua University. The Flexible AC Transmission System (FACTS) technology which uses power electronics to improve the efficiency and quality of the electrical generation, transmission and distribution system is considered to be one of the most significant technological innovations for power systems in the 20th century. The advanced static var generator (ASVG) is a key FACTS device.

  16. An AC magnetohydrodynamic micropump: towards a true integrated microfluidic system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, A P; Lemoff, A V; McConaghy, C F; Miles, R R

    1999-03-01

    An AC Magnetohydrodynamic (MHD) micropump has been demonstrated in which the Lorentz force is used to propel an electrolytic solution along a microchannel etched in silicon. This micropump has no moving parts, produces a continuous (not pulsatile) flow, and is compatible with solutions containing biological specimens. micropump, using the Lorentz force as the pumping mechanism for biological analysis. The AC Magnetohydrodynamic (MHD) micropump investigated produces a continuous flow and allows for complex microchannel design.

  17. The topological AC effect on non-commutative phase space

    Energy Technology Data Exchange (ETDEWEB)

    Li, Kang [Hangzhou Teachers College, Department of Physics, Hangzhou (China); The Abdus Salam International Center for Theoretical Physics, Trieste (Italy); Wang, Jianhua [Shaanxi University of Technology, Department of Physics, Hanzhong (China); The Abdus Salam International Center for Theoretical Physics, Trieste (Italy)

    2007-05-15

    The Aharonov-Casher (AC) effect in non-commutative (NC) quantum mechanics is studied. Instead of using the star product method, we use a generalization of Bopp's shift method. After solving the Dirac equations both on non-commutative space and non-commutative phase space by the new method, we obtain corrections to the AC phase on NC space and NC phase space, respectively. (orig.)

  18. Diagnostics of the Fermilab Tevatron using an AC dipole

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, Ryoichi [Univ. of Texas, Austin, TX (United States)

    2008-08-01

    The Fermilab Tevatron is currently the world's highest energy colliding beam facility. Its counter-rotating proton and antiproton beams collide at 2 TeV center-of-mass. Delivery of such intense beam fluxes to experiments has required improved knowledge of the Tevatron's beam optical lattice. An oscillating dipole magnet, referred to as an AC dipole, is one of such a tool to non-destructively assess the optical properties of the synchrotron. We discusses development of an AC dipole system for the Tevatron, a fast-oscillating (f ~ 20 kHz) dipole magnet which can be adiabatically turned on and off to establish sustained coherent oscillations of the beam particles without affecting the transverse emittance. By utilizing an existing magnet and a higher power audio amplifier, the cost of the Tevatron AC dipole system became relatively inexpensive. We discuss corrections which must be applied to the driven oscillation measurements to obtain the proper interpretation of beam optical parameters from AC dipole studies. After successful operations of the Tevatron AC dipole system, AC dipole systems, similar to that in the Tevatron, will be build for the CERN LHC. We present several measurements of linear optical parameters (beta function and phase advance) for the Tevatron, as well as studies of non-linear perturbations from sextupole and octupole elements.

  19. Role of nuclear Lamin A/C in cardiomyocyte functions.

    Science.gov (United States)

    Carmosino, Monica; Torretta, Silvia; Procino, Giuseppe; Gerbino, Andrea; Forleo, Cinzia; Favale, Stefano; Svelto, Maria

    2014-10-01

    Lamin A/C is a structural protein of the nuclear envelope (NE) and cardiac involvement in Lamin A/C mutations was one of the first phenotypes to be reported in humans, suggesting a crucial role of this protein in the cardiomyocytes function. Mutations in LMNA gene cause a class of pathologies generically named 'Lamanopathies' mainly involving heart and skeletal muscles. Moreover, the well-known disease called Hutchinson-Gilford Progeria Syndrome due to extensive mutations in LMNA gene, in addition to the systemic phenotype of premature aging, is characterised by the death of patients at around 13 typically for a heart attack or stroke, suggesting again the heart as the main site sensitive to Lamin A/C disfunction. Indeed, the identification of the roles of the Lamin A/C in cardiomyocytes function is a key area of exploration. One of the primary biological roles recently conferred to Lamin A/C is to affect contractile cells lineage determination and senescence. Then, in differentiated adult cardiomyocytes both the 'structural' and 'gene expression hypothesis' could explain the role of Lamin A in the function of cardiomyocytes. In fact, recent advances in the field propose that the structural weakness/stiffness of the NE, regulated by Lamin A/C amount in NE, can 'consequently' alter gene expression. © 2014 Société Française des Microscopies and Société de Biologie Cellulaire de France. Published by John Wiley & Sons Ltd.

  20. AC electrophoretic deposition of organic-inorganic composite coatings.

    Science.gov (United States)

    Yoshioka, T; Chávez-Valdez, A; Roether, J A; Schubert, D W; Boccaccini, A R

    2013-02-15

    Alternating current electrophoretic deposition (AC-EPD) of polyacrylic acid (PAA)-titanium oxide (TiO(2)) nanoparticle composites on stainless steel electrodes was investigated in basic aqueous solution. AC square wave with duty cycle of 80% was applied at a frequency of 1 kHz. FTIR-ATR spectra showed that both AC and direct current (DC) EPD successfully deposited PAA-TiO(2) composites. The deposition rate using AC-EPD was lower than that obtained in direct current DC-EPD. However, the microstructure and surface morphology of the deposited composite coatings were different depending on the type of electric field applied. AC-EPD applied for not more than 5 min led to smooth films without bubble formation, while DC-EPD for 1 min or more showed deposits with microstructural defects possibly as result of water electrolysis. AC-EPD was thus for the first time demonstrated to be a suitable technique to deposit organic-inorganic composite coatings from aqueous suspensions, showing that applying a square wave and frequency of 1 kHz leads to uniform PAA-TiO(2) composite coatings on conductive materials.

  1. A Novel High Performance Bridgeless Ac-Dc Boost Converter

    Directory of Open Access Journals (Sweden)

    S.M.AshrafulAlam Mohon

    2016-08-01

    Full Text Available A new single phase high performance bridgeless AC-DC Boost converter is proposed. The converter is made bridgeless by the use of two unidirectional switches and two diodes at the input ac side for power conversion for both positive and negative half cycle. Because of the high frequency switching, the power factor of the circuit is inherently corrected and it requires a small filter to make the input current near sinusoidal with limited THD. The significant improvement in THD makes the circuit a good choice in applications needing AC-DC conversion with power conditioning. The circuit exhibits such better performances than conventional AC-DC boost converter with variable loads at constant frequency switching with no additional control circuits. The efficiency of the circuit is also satisfactory. Analysis and simulation results of the circuit are obtained by using software simulation. The main advantage of this new AC-DC converter is its superior power quality over conventional AC-DC boost converter

  2. Update on bedside ultrasound (US) diagnosis of acute cholecystitis (AC).

    Science.gov (United States)

    Zenobii, Maria Francesca; Accogli, Esterita; Domanico, Andrea; Arienti, Vincenzo

    2016-03-01

    Acute cholecystitis (AC) represents a principal cause of morbidity worldwide and is one of the most frequent reasons for hospitalization due to gastroenteric tract diseases. AC should be suspected in presence of clinical signs and of gallstones on an imaging study. Upper abdominal US represents the first diagnostic imaging step in the case of suspected AC. Computed tomography (CT) with intravenous contrast (IV) or magnetic resonance imaging (MRI) with gadolinium contrast and technetium hepatobiliary iminodiacetic acid (Tc-HIDA) can be employed to exclude complications. US examination should be performed with right subcostal oblique, with longitudinal and intercostal scans. Normal gallbladder US findings and AC major and minor US signs are described. Polyps, sludge and gallbladder wall thickening represent the more frequent pitfalls and they must be differentiated from stones, duodenal artifacts and many other non-inflammatory conditions that cause wall thickening, respectively. By means of bedside ultrasound, the finding of gallstones in combination with acute pain, when the clinician presses the gallbladder with the US probe (the sonographic Murphy's sign), has a 92.2 % positive predictive value for AC. In our preliminary experience, bedside US-performed by echoscopy (ES) and/or point-of-care US (POCUS) demonstrated good reliability in detecting signs of AC, and was always integrated with physical examination and performed by a skilled operator.

  3. Temperature integration at the AC thermosensory neurons in Drosophila.

    Science.gov (United States)

    Tang, Xin; Platt, Michael D; Lagnese, Christopher M; Leslie, Jennifer R; Hamada, Fumika N

    2013-01-16

    Temperature sensation has a strong impact on animal behavior and is necessary for animals to avoid exposure to harmful temperatures. It is now well known that thermoTRP (transient receptor potential) channels in thermosensory neurons detect a variable range of temperature stimuli. However, little is known about how a range of temperature information is relayed and integrated in the neural circuits. Here, we show novel temperature integration between two warm inputs via Drosophila TRPA channels, TRPA1 and Pyrexia (Pyx). The internal AC (anterior cell) thermosensory neurons, which express TRPA1, detect warm temperatures and mediate temperature preference behavior. We found that the AC neurons were activated twice when subjected to increasing temperatures. The first response was at ∼25°C via TRPA1 channel, which is expressed in the AC neurons. The second response was at ∼27°C via the second antennal segments, indicating that the second antennal segments are involved in the detection of warm temperatures. Further analysis reveals that pyx-Gal4-expressing neurons have synapses on the AC neurons and that mutation of pyx eliminates the second response of the AC neurons. These data suggest that AC neurons integrate both their own TRPA1-dependent temperature responses and a Pyx-dependent temperature response from the second antennal segments. Our data reveal the first identification of temperature integration, which combines warm temperature information from peripheral to central neurons and provides the possibility that temperature integration is involved in the plasticity of behavioral outputs.

  4. Importance of Attenuation Correction (AC) for Small Animal PET Imaging

    DEFF Research Database (Denmark)

    El Ali, Henrik H.; Bodholdt, Rasmus Poul; Jørgensen, Jesper Tranekjær

    2012-01-01

    was performed. Methods: Ten NMRI nude mice with subcutaneous implantation of human breast cancer cells (MCF-7) were scanned consecutively in small animal PET and CT scanners (MicroPETTM Focus 120 and ImTek’s MicroCATTM II). CT-based AC, PET-based AC and uniform AC methods were compared. Results: The activity...... concentration in the same organ with and without AC revealed an overall attenuation recovery of 9–21% for MAP reconstructed images, i.e., SUV without AC could underestimate the true activity at this level. For subcutaneous tumors, the attenuation was 13 ± 4% (9–17%), for kidneys 20 ± 1% (19......–21%), and for bladder 18 ± 3% (15–21%). The FBP reconstructed images showed almost the same attenuation levels as the MAP reconstructed images for all organs. Conclusions: The annihilation photons are suffering attenuation even in small subjects. Both PET-based and CT-based are adequate as AC methods. The amplitude...

  5. Effects of airflow on the distribution of filaments in atmospheric AC dielectric barrier discharge

    Science.gov (United States)

    Fan, Zhihui; Qi, Haicheng; Liu, Yidi; Yan, Huijie; Ren, Chunsheng

    2016-12-01

    Atmospheric-pressure dielectric barrier discharge (DBD) accompanied by airflow has attracted a significant attention for its extensive applications. In this paper, the effects of airflow on the characteristics of the atmospheric air DBD plasma are experimentally investigated using the DBD reactor excited by a 15 kHz AC power source. In order to study the discharge filaments distribution at different flow rates, transparent conductive indium tin oxide film is used as the upper electrode, and quartz glasses are used as insulated dielectrics. Experiment results prove that the breakdown voltage is decreased and more current pulses with declined amplitudes are produced when the airflow is introduced into the discharge gap. It is confirmed that although the discharge seems to be diffuse in the presence of airflow to the naked eyes, the discharge mode remains filamentary in the intensified charge-coupled device images within a single AC cycle. By acquiring the images with a different exposure time, it can be recognized that the discharge filaments move along the flow field direction with a velocity less than the corresponding flow rate. The movement of discharge filaments is attributed to the motion of the charge induced by the airflow.

  6. Instabilities, turbulence and transport in a magnetized plasma; Instabilites, turbulence et transport dans un plasma magnetise

    Energy Technology Data Exchange (ETDEWEB)

    Garbet, X

    2001-06-01

    The purpose of this work is to introduce the main processes that occur in a magnetized plasma. During the last 2 decades, the understanding of turbulence has made great progress but analytical formulas and simulations are far to produce reliable predictions. The values of transport coefficients in a tokamak plasma exceed by far those predicted by the theory of collisional transport. This phenomenon is called abnormal transport and might be due to plasma fluctuations. An estimation of turbulent fluxes derived from the levels of fluctuations, is proposed. A flow description of plasma allows the understanding of most micro-instabilities. The ballooning representation deals with instabilities in a toric geometry. 3 factors play an important role to stabilize plasmas: density pinch, magnetic shear and speed shear. The flow model of plasma gives an erroneous value for the stability threshold, this is due to a bad description of the resonant interaction between wave and particle. As for dynamics, flow models can be improved by adding dissipative terms so that the linear response nears the kinetic response. The kinetic approach is more accurate but is complex because of the great number of dimensions involved. (A.C.)

  7. Conductivity of a two-dimensional guiding center plasma.

    Science.gov (United States)

    Montgomery, D.; Tappert, F.

    1972-01-01

    The Kubo method is used to calculate the electrical conductivity of a two-dimensional, strongly magnetized plasma. The particles interact through (logarithmic) electrostatic potentials and move with their guiding center drift velocities (Taylor-McNamara model). The thermal equilibrium dc conductivity can be evaluated analytically, but the ac conductivity involves numerical solution of a differential equation. Both conductivities fall off as the inverse first power of the magnetic field strength.

  8. Expression of Recombinant Pregnancy-associated Plasma Protein-A

    Institute of Scientific and Technical Information of China (English)

    CHENG; Bin-yan; LI; Zi-ying; ZHANG; Xue-feng; LIU; Yi-bing

    2013-01-01

    Pregnancy-associated plasma protein-A(PAPP-A)is producted by the syntrophoblast tissue of the placenta and decidual cells.It belongs to macromolecular glycoprotein.PAPP-A is a sensitive serum marker of Down’s syndrome and has clinical valuable in the early identification of acute coronary syndrome(ACS).According to the structure of PAPP-A,PAPP-A DNA is divided into five segments(S1-S5)for

  9. 21 CFR 880.6320 - AC-powered medical examination light.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered medical examination light. 880.6320... Miscellaneous Devices § 880.6320 AC-powered medical examination light. (a) Identification. An AC-powered medical examination light is an AC-powered device intended for medical purposes that is used to illuminate...

  10. Monoclonal antibodies AC-43 and AC-29 disrupt Plasmodium vivax development in the Indian malaria vector Anopheles culicifacies (Diptera: culicidae)

    Indian Academy of Sciences (India)

    Manoj Chugh; B R Gulati; S K Gakhar

    2010-03-01

    A repertoire of monoclonal antibodies (mAbs) was generated against the midgut proteins of Anopheles culicifacies mosquitoes. The mAbs AC-43 and AC-29 significantly inhibited Plasmodium vivax development inside the mosquito midgut. The number of oocysts that developed was reduced by 78.6% when mosquitoes ingested a combination of these two mAbs along with the blood meal. AC-43 mAb binds to the epitope common in 97, 80 and 43 kDa polypeptides from the midgut protein extract, as indicated by western blot analysis. Similarly, the mAb AC-29 recognized 52, 44, 40 and 29 kDa polypeptides. These female midgut-specific polypeptides are shared between An. culicifacies and An. stephensi, two major vectors of malaria in India. Deglycosylation assays revealed that -linked carbohydrates are the major components in epitopes corresponding to AC-43 and AC-29. Gold particle labelling revealed that both these mAbs preferentially bind to glycoproteins at the apical microvilli and the microvillus-associated network present inside transverse sections of the gut epithelium. These regions are particularly known to have receptors for ookinetes, which enable them to cross this epithelial barrier and provide them with certain necessary chemicals or components for further development into oocysts. Therefore, these glycoproteins appear to be potential candidates for a vectordirected transmission-blocking vaccine (TBV).

  11. Enhanced removal of humic acid from micro-polluted source water in a surface discharge plasma system coupled with activated carbon.

    Science.gov (United States)

    Wang, Tiecheng; Li, Yujuan; Qu, Guangzhou; Sun, Qiuhong; Liang, Dongli; Hu, Shibin; Zhu, Lingyan

    2017-07-26

    Surface discharge plasma (SDP) combined with activated carbon (AC) was employed to eliminate dissolved organic matter from micro-polluted source water, with humic acid (HA) as the model pollutant. Synergistic effect on HA removal was observed in the SDP-AC system; HA removal efficiency reached 60.9% within 5-min treatment in the SDP-AC system with 5.0 g AC addition, whereas 16.7 and 17.4% of HA were removed in sole SDP system and AC adsorption, respectively. Scanning electron microscope and Boehm titration analysis showed that chemical reactions between active species and functional groups of AC occurred. The existence of isopropanol or benzoquinone exhibited inhibitive effects on HA removal in the SDP system, while these inhibitive effects were weakened in the SDP-AC system. The influences of AC on ozone equivalent concentration and H2O2 concentration were evaluated, and there were approximately 39 and 20% decline in ozone equivalent concentration and H2O2 concentration within 6-min treatment in the SDP-AC system, respectively, compared with those in the sole SDP system. Dissolved organic carbon, specific ultraviolet absorbance, and UV absorption ratios analysis demonstrated that the SDP treatment destroyed the chromophoric groups, double bonds, and aromatic structure of HA molecules, and these destructive actions were strengthened by AC.

  12. Integration issues of a plasma contactor Power Electronics Unit

    Science.gov (United States)

    Pinero, Luis R.; York, Kenneth W.; Bowers, Glen E.

    1995-06-01

    A hollow cathode-based plasma contactor is baselined on International Space Station Alpha (ISSA) for spacecraft charge control. The plasma contactor system consists of a hollow cathode assembly (HCA), a power electronics unit (PEU), and an expellant management unit (EMU). The plasma contactor has recently been required to operate in a cyclic mode to conserve xenon expellant and extend system life. Originally, a DC cathode heater converter was baselined for a continuous operation mode because only a few ignitions of the hollow cathode were expected. However, for cyclic operation, a DC heater supply can potentially result in hollow cathode heater component failure due to the DC electrostatic field. This can prevent the heater from attaining the proper cathode tip temperature for reliable ignition of the hollow cathode. To mitigate this problem, an AC cathode heater supply was therefore designed, fabricated, and installed into a modified PEU. The PEU was tested using resistive loads and then integrated with an engineering model hollow cathode to demonstrate stable steady-state operation. Integration issues such as the effect of line and load impedance on the output of the AC cathode heater supply and the characterization of the temperature profile of the heater under AC excitation were investigated.

  13. Integration issues of a plasma contactor Power Electronics Unit

    Science.gov (United States)

    Pinero, Luis R.; York, Kenneth W.; Bowers, Glen E.

    1995-01-01

    A hollow cathode-based plasma contactor is baselined on International Space Station Alpha (ISSA) for spacecraft charge control. The plasma contactor system consists of a hollow cathode assembly (HCA), a power electronics unit (PEU), and an expellant management unit (EMU). The plasma contactor has recently been required to operate in a cyclic mode to conserve xenon expellant and extend system life. Originally, a DC cathode heater converter was baselined for a continuous operation mode because only a few ignitions of the hollow cathode were expected. However, for cyclic operation, a DC heater supply can potentially result in hollow cathode heater component failure due to the DC electrostatic field. This can prevent the heater from attaining the proper cathode tip temperature for reliable ignition of the hollow cathode. To mitigate this problem, an AC cathode heater supply was therefore designed, fabricated, and installed into a modified PEU. The PEU was tested using resistive loads and then integrated with an engineering model hollow cathode to demonstrate stable steady-state operation. Integration issues such as the effect of line and load impedance on the output of the AC cathode heater supply and the characterization of the temperature profile of the heater under AC excitation were investigated.

  14. Plasma Free Metanephrines

    Science.gov (United States)

    ... be limited. Home Visit Global Sites Search Help? Plasma Free Metanephrines Share this page: Was this page helpful? Also known as: Plasma Metanephrines Formal name: Fractionated Plasma Free Metanephrines (Metanephrine ...

  15. Improved plasma accelerator

    Science.gov (United States)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  16. An AC/AC Direct Power Conversion Topology Having Multiple Power Grid Connections with Adjustable Loading

    DEFF Research Database (Denmark)

    Klumpner, Christian; Blaabjerg, Frede

    2004-01-01

    Normally, a power converter has one supply port to connect to the power grid and one or multiple output ports to connect to AC loads that require variable voltage and variable frequency. As the trend on the energy market is towards deregulation, new converter topologies are needed to allow...... independent producers/consumers to connect to multiple distribution grids in order to optimise the electricity price, as this will vary during the day from one power distribution company to another one. It will be needed to have a load that can smoothly adjust the power consumed from each power grid in order...... these fraction power will be a necessary feature on a deregulated energy market. This paper presents a new topology of a power converter based on the Direct Power Conversion concept, which is able to connect to multiple grids and provide complete decoupling between without circulating power between the grids...

  17. Plasma physics and fusion plasma electrodynamics

    CERN Document Server

    Bers, Abraham

    2016-01-01

    Plasma is a ubiquitous state of matter at high temperatures. The electrodynamics of plasmas encompasses a large number of applications, from understanding plasmas in space and the stars, to their use in processing semiconductors, and their role in controlled energy generation by nuclear fusion. This book covers collective and single particle dynamics of plasmas for fully ionized as well as partially ionized plasmas. Many aspects of plasma physics in current fusion energy generation research are addressed both in magnetic and inertial confinement plasmas. Linear and nonlinear dynamics in hydrodynamic and kinetic descriptions are offered, making both simple and complex aspects of the subject available in nearly every chapter. The approach of dividing the basic aspects of plasma physics as "linear, hydrodynamic descriptions" to be covered first because they are "easier", and postponing the "nonlinear and kinetic descriptions" for later because they are "difficult" is abandoned in this book. For teaching purpose...

  18. Fabrication of All Glass Bifurcation Microfluidic Chip for Blood Plasma Separation

    Directory of Open Access Journals (Sweden)

    Hyungjun Jang

    2017-02-01

    Full Text Available An all-glass bifurcation microfluidic chip for blood plasma separation was fabricated by a cost-effective glass molding process using an amorphous carbon (AC mold, which in turn was fabricated by the carbonization of a replicated furan precursor. To compensate for the shrinkage during AC mold fabrication, an enlarged photoresist pattern master was designed, and an AC mold with a dimensional error of 2.9% was achieved; the dimensional error of the master pattern was 1.6%. In the glass molding process, a glass microchannel plate with negligible shape errors (~1.5% compared to AC mold was replicated. Finally, an all-glass bifurcation microfluidic chip was realized by micro drilling and thermal fusion bonding processes. A separation efficiency of 74% was obtained using the fabricated all-glass bifurcation microfluidic chip.

  19. Effect of hydrogen sulphide-donating sildenafil (ACS6) on erectile function and oxidative stress in rabbit isolated corpus cavernosum and in hypertensive rats.

    Science.gov (United States)

    Shukla, Nilima; Rossoni, Giuseppe; Hotston, Matthew; Sparatore, Anna; Del Soldato, Piero; Tazzari, Valerio; Persad, Raj; Angelini, Gianni D; Jeremy, Jamie Y

    2009-06-01

    OBJECTIVE To study the effect of the H(2)S-donating derivative of sildenafil (ACS6) compared to sildenafil citrate and sodium hydrosulphide (NaHS) on relaxation, superoxide formation and NADPH oxidase and type 5 phosphodiesterase (PDE5) expression in isolated rabbit cavernosal tissue and smooth muscle cells (CSMCs), and in vivo on indices of oxidative stress induced with buthionine sulphoximine (BSO). MATERIALS AND METHODS Relaxation was studied in an organ bath in response to carbachol and after incubation with interleukin-1beta for 12 h. CSMCs were incubated with tumour-necrosis factor-alpha or the thromboxane A(2) (TXA(2)) analogue, U46619, with or with no sildenafil citrate, ACS6 or NaHS for 16 h. Superoxide formation and the expression of p47(phox) (an active subunit of the NADPH oxidase complex) and PDE5 protein was then assessed using Western blotting. Rats were also treated with BSO (with or with no sildenafil citrate or ACS6) for 7 days; cavernosal cGMP, cAMP, glutathionine and plasma TXA(2) and 8-isoprostane F(2alpha) was measured by enzyme-linked immunosorbent assay. RESULTS ACS6 and sildenafil citrate relaxed cavernosal smooth muscle equipotently; NaHS alone had little effect at up to 100 microm. The formation of superoxide and expression of p47(phox) and PDE5 was reduced by ACS6, sildenafil citrate and NaHS (order of potency: ACS6 > sildenafil citrate > NaHS). The effects of ACS6 were blocked by inhibitors of protein kinase A (PKA) and PKG. In rats treated with BSO, both ASC6 and sildenafil citrate reduced the increased plasma levels of TXA(2) and 8-isoprostane F(2alpha) but increased cGMP, cAMP and glutathionine levels in corpus cavernosum. CONCLUSIONS By virtue of a dual action on PKA and PKG activation, ACS6 not only promotes erection, acutely, but might also have a long-term beneficial effect through inhibition of oxidative stress and downregulation of PDE5.

  20. Temas de Física para Ingeniería: Acústica

    OpenAIRE

    Beléndez Vázquez, Augusto

    1992-01-01

    Acústica, fluidos y termodinámica: "Acústica". Ondas sonoras, propagación. Sonidos puros, sonidos complejos y ruidos. Velocidad de propagación del sonido. Intensidad del sonido y potencia acústica. Impedancia acústica y transmisión del sonido. Medición del campo acústico: niveles. Audición. Interferencia de ondas sonoras y pulsaciones. Tubos sonoros. Efecto Doppler.

  1. Temas de Física para Ingeniería: Acústica

    OpenAIRE

    Beléndez Vázquez, Augusto

    1992-01-01

    Acústica, fluidos y termodinámica: "Acústica". Ondas sonoras, propagación. Sonidos puros, sonidos complejos y ruidos. Velocidad de propagación del sonido. Intensidad del sonido y potencia acústica. Impedancia acústica y transmisión del sonido. Medición del campo acústico: niveles. Audición. Interferencia de ondas sonoras y pulsaciones. Tubos sonoros. Efecto Doppler.

  2. Comparison of the characteristics of atmospheric pressure plasma jets using different working gases and applications to plasma-cancer cell interactions

    Directory of Open Access Journals (Sweden)

    Hea Min Joh

    2013-09-01

    Full Text Available Atmospheric pressure plasma jets employing nitrogen, helium, or argon gases driven by low-frequency (several tens of kilohertz ac voltage and pulsed dc voltage were fabricated and characterized. The changes in discharge current, optical emission intensities from reactive radicals, gas temperature, and plume length of plasma jets with the control parameters were measured and compared. The control parameters include applied voltage, working gas, and gas flow rate. As an application to plasma-cancer cell interactions, the effects of atmospheric pressure plasma jet on the morphology and intracellular reactive oxygen species (ROS level of human lung adenocarcinoma cell (A549 and human bladder cancer cell (EJ were explored. The experimental results show that the plasma can effectively control the intracellular concentrations of ROS. Although there exist slight differences in the production of ROS, helium, argon, or nitrogen plasma jets are found to be useful in enhancing the intracellular ROS concentrations in cancer cells.

  3. 一种简单新型拓扑Cuk AC/AC变换器及其仿真研究%A New Simple Topology of Cuk AC/AC Converter and Its Simulation

    Institute of Scientific and Technical Information of China (English)

    陈溪; 刘韬; 谭光慧; 纪延超

    2006-01-01

    由Cuk DC/DC变换器的拓扑结构导出一种只具有两个开关的PWM AC/AC变换器的简单新型拓扑--Cuk AC/AC变换器.给出单相和三相Cuk AC/AC变换器的拓扑结构,分析Cuk AC/AC变换器的外特性及小信号特性.仿真结果验证了所提的Cuk AC/AC变换器的合理性和可行性.

  4. Complement activation in plasma before and after infliximab treatment in Crohn disease

    DEFF Research Database (Denmark)

    Zimmermann-Nielsen, E; Agnholt, J; Thorlacius-Ussing, O

    2003-01-01

    BACKGROUND: Crohn disease is characterized by up-regulated intestinal inflammation mainly caused by increased tumour necrosis factor alpha (TNF-alpha) levels. However, the complement system (C) may also have a role in maintaining inflammation. METHODS: Plasma from 26 patients with Crohn disease...... complicated by fistulizing ano-rectal disease was collected before and after three Infliximab infusions (5 mg kg(-1)). RESULTS: Before treatment, the C3-activation capacities (C3-AC) in plasma from patients with Crohn disease were comparable with values obtained from healthy controls. The classical C pathway......-mediated C3-AC, mannan-binding lectin C4-AC, leucocyte count, C-reactive protein concentration and Crohn Disease Activity Index decreased significantly 8 weeks after the first infusion of Infliximab (P

  5. Modelling ac ripple currents in HTS coated conductors

    Science.gov (United States)

    Xu, Zhihan; Grilli, Francesco

    2015-10-01

    Dc transmission using high temperature superconducting (HTS) coated conductors (CCs) offers a promising solution to the globally growing demand for effective, reliable and economic transmission of green energy up to the gigawatt level over very long distances. The credible estimation of the losses and thereby the heat dissipation involved, where ac ripples (introduced in rectification/ac-dc conversion) are viewed as a potential source of notable contribution, is highly essential for the rational design of practical HTS dc transmission cables and corresponding cryogenic systems to fulfil this demand. Here we report a targeted modelling study into the ac losses in a HTS CC subject to dc and ac ripple currents simultaneously, by solving Maxwell’s equations using the finite element method (FEM) in the commercial software package COMSOL. It is observed that the instantaneous loss exhibits only one peak per cycle in the HTS CC subject to sinusoidal ripples, given that the amplitude of the ac ripples is smaller than approximately 20% of that of the dc current. This is a distinct contrast to the usual observation of two peaks per cycle in a HTS CC subject to ac currents only. The unique mechanism is also revealed, which is directly associated with the finding that, around any local minima of the applied ac ripples, the critical state of -J c is never reached at the edges of the HTS CC, as it should be according to the Bean model. When running further into the longer term, it is discovered that the ac ripple loss of the HTS CC in full-wave rectification decays monotonically, at a speed which is found to be insensitive to the frequency of the applied ripples within our targeted situations, to a relatively low level of approximately 1.38 × 10-4 W m-1 in around 1.7 s. Comparison between this level and other typical loss contributions in a HTS dc cable implies that ac ripple currents in HTS CCs should only be considered as a minor source of dissipation in superconducting dc

  6. Impedance, AC conductivity and dielectric behavior Adeninium Trichloromercurate (II)

    Science.gov (United States)

    Fersi, M. Amine; Chaabane, I.; Gargouri, M.

    2016-09-01

    In this work, we report the measurements impedance spectroscopy technique for the organic-inorganic hybrid compound (C5H6N5) HgCl3, 11/2H2O measured in the 209 Hz-5 MHz frequency range from 378 to 428 K. Besides, the Cole-Cole (Z″ versus Z‧) plots were well fitted to an equivalent circuit built up by a parallel combination of resistance (R), fractal capacitance (CPE) and capacitance (C). Furthermore, the AC conductivity was investigated as a function of temperature and frequency in the same range. The experiment results indicated that AC conductivity (σac) was proportional to σdc + A ωS . The obtained results are discussed in terms of the correlated barrier hopping (CBH) model. An agreement between the experimental and theoretical results suggests that the AC conductivity behavior of Adeninium Trichloromercurate (II) can be successfully explained by CBH model. The contribution of single polaron hopping to AC conductivity in a present alloy was also studied.

  7. Design and synthesis of {sup 225}Ac radioimmunopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    McDevitt, Michael R.; Ma, Dangshe; Simon, Jim; Frank, R. Keith; Scheinberg, David A. E-mail: d-scheinberg@ski.mskcc.org

    2002-12-01

    The alpha-particle-emitting radionuclides {sup 213}Bi, {sup 211}At, {sup 224}Ra are under investigation for the treatment of leukemias, gliomas, and ankylosing spondylitis, respectively. {sup 213}Bi and {sup 211}At were attached to monoclonal antibodies and used as targeted immunotherapeutic agents while unconjugated {sup 224}Ra chloride selectively seeks bone. {sup 225}Ac possesses favorable physical properties for radioimmunotherapy (10 d half-life and 4 net alpha particles), but has a history of unfavorable radiolabeling chemistry and poor metal-chelate stability. We selected functionalized derivatives of DOTA as the most promising to pursue from out of a group of potential {sup 225}Ac chelate compounds. A two-step synthetic process employing either MeO-DOTA-NCS or 2B-DOTA-NCS as the chelating moiety was developed to attach {sup 225}Ac to monoclonal antibodies. This method was tested using several different IgG systems. The chelation reaction yield in the first step was 93{+-}8% radiochemically pure (n=26). The second step yielded {sup 225}Ac-DOTA-IgG constructs that were 95{+-}5% radiochemically pure (n=27) and the mean percent immunoreactivity ranged from 25% to 81%, depending on the antibody used. This process has yielded several potential novel targeted {sup 225}Ac-labeled immunotherapeutic agents that may now be evaluated in appropriate model systems and ultimately in humans.

  8. AC propulsion system for an electric vehicle, phase 2

    Science.gov (United States)

    Slicker, J. M.

    1983-01-01

    A second-generation prototype ac propulsion system for a passenger electric vehicle was designed, fabricated, tested, installed in a modified Mercury Lynx vehicle and track tested at the Contractor's site. The system consisted of a Phase 2, 18.7 kw rated ac induction traction motor, a 192-volt, battery powered, pulse-width-modulated, transistorized inverter packaged for under rear seat installation, a 2-axis, 2-speed, automatically-shifted mechanical transaxle and a microprocessor-based powertrain/vehicle controller. A diagnostics computer to assist tuning and fault finding was fabricated. Dc-to-mechanical-system efficiency varied from 78% to 82% as axle speed/torque ranged from 159 rpm/788 nm to 65 rpm/328 nm. Track test efficiency results suggest that the ac system will be equal or superior to dc systems when driving urban cycles. Additional short-term work is being performed under a third contract phase (AC-3) to raise transaxle efficiency to predicted levels, and to improve starting and shifting characteristics. However, the long-term challenge to the system's viability remains inverter cost. A final report on the Phase 2 system, describing Phase 3 modifications, will be issued at the conclusion of AC-3.

  9. AC Zeeman potentials for atom chip-based ultracold atoms

    Science.gov (United States)

    Fancher, Charles; Pyle, Andrew; Ziltz, Austin; Aubin, Seth

    2015-05-01

    We present experimental and theoretical progress on using the AC Zeeman force produced by microwave magnetic near-fields from an atom chip to manipulate and eventually trap ultracold atoms. These AC Zeeman potentials are inherently spin-dependent and can be used to apply qualitatively different potentials to different spin states simultaneously. Furthermore, AC Zeeman traps are compatible with the large DC magnetic fields necessary for accessing Feshbach resonances. Applications include spin-dependent trapped atom interferometry and experiments in 1D many-body physics. Initial experiments and results are geared towards observing the bipolar detuning-dependent nature of the AC Zeeman force at 6.8 GHz with ultracold 87Rb atoms trapped in the vicinity of an atom chip. Experimental work is also underway towards working with potassium isotopes at frequencies of 1 GHz and below. Theoretical work is focused on atom chip designs for AC Zeeman traps produced by magnetic near-fields, while also incorporating the effect of the related electric near-fields. Electromagnetic simulations of atom chip circuits are used for mapping microwave propagation in on-chip transmission line structures, accounting for the skin effect, and guiding impedance matching.

  10. AC losses in circular arrangements of parallel superconducting tapes

    DEFF Research Database (Denmark)

    Kühle (fratrådt), Anders Van Der Aa; Træholt, Chresten; Däumling, Manfred

    1998-01-01

    The DC and AC properties of superconducting tapes connected in parellel and arranged in a single closed layer on two tubes (correspondig to power cable models with infinite pitch) with different diameters are compared. We find that the DC properties, i.e. the critical currents of the two arrangem......The DC and AC properties of superconducting tapes connected in parellel and arranged in a single closed layer on two tubes (correspondig to power cable models with infinite pitch) with different diameters are compared. We find that the DC properties, i.e. the critical currents of the two...... arrangements, scale with the number of tapes and hence appear to be independent of the diameter.However, the AC loss per tape (for a given current per tape) appears to decrease with increasing diameter of the circular arrangement. Compared to a model for the AC loss in a continuous superconducting layer...... (Monoblock model) the measured values are about half an order of magnitude higher than expected for the small diameter arrangement. When compared to the AC loss calculated for N individual superconducting tapes using a well known model ( Norris elliptical) the difference is slightly smaller....

  11. Plasma phospholipid fatty acid profiles in Korean adults with and without acute coronary syndrome

    Science.gov (United States)

    Background and Objectives: Acute coronary syndrome (ACS), a clinical manifestation of coronary artery disease presenting as unstable angina and/or myocardial infarction, is the third-leading cause of death in South Korea. Plasma phospholipid (PL) fatty acid profiles are considered objective biomarke...

  12. Decomposition of Chemical Chain Molecules with Atmospheric Pressure Plasma

    Science.gov (United States)

    Tansli, Murat; Tasal, Erol

    2016-10-01

    Chemical chain molecules' decomposition is an interesting subject area for the atmospheric pressure plasma applications. The effects of the atmospheric pressure argon plasma on 4-((2-methoxyphenyl)Diazenyl)Benzene-1,3,-Diol molecule at room temperature are investigated. This molecule is one of the industrial dye molecules used widely. When considering the ecological life, this molecule will be very harmful and danger. We suggest a different, easy and useful decomposing method for such molecules. Atmospheric pressure plasma jet was principally treated for this decomposing of the molecule. Fourier transform infrared spectrometry (FT-IR) was used to characterization of the molecule after the plasma application to molecule in liquid phase with ethanol and methanol solvents. The atmospheric-pressure plasma jet of argon (Ar) as non-equilibrium has been formed by ac-power generator with frequency - 24 kHz and voltage - 12 kV. Characterizations for solutions prepared with ethanol and methanol solvents of molecule have been examined after applying (duration: 3 minutes) the atmospheric pressure plasma jet. The molecule was broken at 6C-7N =8N-9C stretching peak after the plasma treatment. The new plasma photo-products for ethanol and methanol solutions were produced as 6C-7N-8N =9C (strong, varying) and 12C =17O (strong, wide) stretching peaks.

  13. COMPARISON OF BACTERIAL ADSORPTION AND ANTIBACTERIAL PROPERTIES BETWEEN AC AND AC(Ag)%AC及AC(Ag)对细菌的吸附及灭菌功能的对比研究

    Institute of Scientific and Technical Information of China (English)

    万怡灶; 王玉林; 董向红; 周福刚; 成国祥; 温廷益; 韩森

    2000-01-01

    测定了活性碳(AC)及载银活性碳(AC(Ag))的比表面积和孔径分布曲线,对比研究了AC及AC(Ag))对大肠杆菌的吸附能力和灭菌性能.结果表明,载银后,虽然AC(Ag)的比表面积下降,但由于银的存在,使其吸附的大肠杆菌数量高于AC,而吸附速率低于AC.灭菌试验表明,AC对大肠杆菌没有杀灭能力,而AC(Ag)对大肠杆菌有较好的灭菌功能.

  14. Comparison of H2 and He carbon cleaning mechanisms in extreme ultraviolet induced and surface wave discharge plasmas

    CERN Document Server

    Dolgov, A; Rachimova, T; Kovalev, A; Vasilyeva, A; Lee, C J; Krivtsun, V M; Yakushev, O; Bijkerk, F

    2013-01-01

    Cleaning of contamination of optical surfaces by amorphous carbon (a-C) is highly relevant for extreme ultraviolet (EUV) lithography. We have studied the mechanisms for a-C removal from a Si surface. By comparing a-C removal in a surface wave discharge (SWD) plasma and an EUV-induced plasma, the cleaning mechanisms for hydrogen and helium gas environments were determined. The C-atom removal per incident ion was estimated for different sample bias voltages and ion fluxes. It was found that H2 plasmas generally had higher cleaning rates than He plasmas: up to seven times higher for more negatively biased samples in EUV induced plasma. Moreover, for H2, EUV induced plasma was found to be 2-3 times more efficient at removing carbon than the SWD plasma. It was observed carbon removal during exposure to He is due to physical sputtering by He+ ions. In H2, on the other hand, the increase in carbon removal rates is due to chemical sputtering. This is a new C cleaning mechanism for EUV-induced plasma, which we call "E...

  15. Fusion plasma physics

    CERN Document Server

    Stacey, Weston M

    2012-01-01

    This revised and enlarged second edition of the popular textbook and reference contains comprehensive treatments of both the established foundations of magnetic fusion plasma physics and of the newly developing areas of active research. It concludes with a look ahead to fusion power reactors of the future. The well-established topics of fusion plasma physics -- basic plasma phenomena, Coulomb scattering, drifts of charged particles in magnetic and electric fields, plasma confinement by magnetic fields, kinetic and fluid collective plasma theories, plasma equilibria and flux surface geometry, plasma waves and instabilities, classical and neoclassical transport, plasma-materials interactions, radiation, etc. -- are fully developed from first principles through to the computational models employed in modern plasma physics. The new and emerging topics of fusion plasma physics research -- fluctuation-driven plasma transport and gyrokinetic/gyrofluid computational methodology, the physics of the divertor, neutral ...

  16. Variable transposition of eight maize activator (ac) elements located on the short arm of chromosome 1.

    Science.gov (United States)

    Sheridan, William F

    2011-09-01

    Eight Activator (Ac) transposable elements mapped to the maize chromosome arm 1S were assessed for Ac transposition rates. For each of the Ac stocks, plants homozygous for the single Ac element and the Ds reporter r1-sc:m3 on chromosome 10 were crossed as females by a homozygous r1-sc:m3 tester color-converted W22 line. The resulting ears produced mostly coarsely spotted kernels and a low frequency of either near-colorless fine-spotted kernels or nonspotted kernels. The relative frequency of these two types of near-colorless kernels differed among the eight Ac stocks. The extent to which increased Ac dosage results in nonspotted kernels may be Ac-specific. Although all of the Ac elements are in near-isogenic inbred W22 lines, they varied to a large extent in their transposition frequency. These differences might possibly result from structural differences among the Ac elements. Because one pair of Ac elements derived from Ac33 on chromosome arm 5S differed about 13-fold in transposition frequency and a second pair of Ac elements derived from Ac12 on chromosome arm 1S differed about 3-fold in transposition frequency, this is not a likely explanation for all eight Ac elements. The data presented here support the notion that the differences in transposition frequency of the eight Ac elements may be a reflection of variability in Ac transcription or accessibility of the transposase to the Ac element, resulting from differences in the chromatin environments wherein the Ac elements are located. This is the first report of variability in transposition rates among different Ac donor lines.

  17. International movement of plasma and plasma contracting.

    Science.gov (United States)

    Farrugia, A

    2005-01-01

    Plasma fractionation is a global business characterised by technological stability, increasing consolidation and a high level of regulatory oversight. All these factors affect the ease with which plasma derivatives can be accessed in the world market. As domestic regulatory measures in the first world blood economies become increasingly resonant to the precautionary approach, the availability of plasma as a raw material, as well as its cost, become an increasingly significant component in the cost of the final product. This decreases the amount of plasma which fractionators are able to allocate for export activities. Also, regulatory standards in the country of manufacture will reflect priorities in that country which may not be similar to those in export markets, but which will affect entry to those markets. While many countries possess a fractionation capacity, the limiting factor in supply worldwide is the amount of plasma available, and nationalistic drivers for each country to have its own plant are inimical to product safety and supply. Rather, the provision of sufficient supplies of domestic plasma should be the focus of resource allocation, with a choice of an appropriate contract fractionator. However, contract fractionation too may be affected by domestic considerations unrelated to the needs of the country of plasma origin. This chapter will review the global plasma market and the influences on plasma and plasma product movement across national borders. Problems in ensuring adequate safety and supply will be identified, and some tentative approaches to the amelioration of current barriers to the provision of plasma derivatives will be outlined.

  18. Superconducting shielded core reactor with reduced AC losses

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Yung S.; Hull, John R.

    2006-04-04

    A superconducting shielded core reactor (SSCR) operates as a passive device for limiting excessive AC current in a circuit operating at a high power level under a fault condition such as shorting. The SSCR includes a ferromagnetic core which may be either closed or open (with an air gap) and extends into and through a superconducting tube or superconducting rings arranged in a stacked array. First and second series connected copper coils each disposed about a portion of the iron core are connected to the circuit to be protected and are respectively wound inside and outside of the superconducting tube or rings. A large impedance is inserted into the circuit by the core when the shielding capability of the superconducting arrangement is exceeded by the applied magnetic field generated by the two coils under a fault condition to limit the AC current in the circuit. The proposed SSCR also affords reduced AC loss compared to conventional SSCRs under continuous normal operation.

  19. On the Application of TLS Techniques to AC Electrical Drives

    Directory of Open Access Journals (Sweden)

    M. Cirrincione

    2005-03-01

    Full Text Available This paper deals with the application of a new neuron, the TLS EXIN neuron, to AC induction motor drives. In particular, it addresses two important subjects of AC induction motor drives: the on-line estimation of the electrical parameters of the machine and the speed estimation in sensorless drives. On this basis, this work summarizes the parameter estimation and sensorless techniques already developed by the authors over these last few years, all based on the TLS EXIN. With regard to sensorless, two techniques are proposed: one based on the MRAS and the other based on the full-order Luenberger observer. The work show some of the most significant results obtained by the authors in these fields and stresses the important potentiality of this new neural technique in AC induction machine drives.

  20. Neural network based PWM AC chopper fed induction motor drive

    Directory of Open Access Journals (Sweden)

    Venkatesan Jamuna

    2009-01-01

    Full Text Available In this paper, a new Simulink model for a neural network controlled PWM AC chopper fed single phase induction motor is proposed. Closed loop speed control is achieved using a neural network controller. To maintain a constant fluid flow with a variation in pressure head, drives like fan and pump are operated with closed loop speed control. The need to improve the quality and reliability of the drive circuit has increased because of the growing demand for improving the performance of motor drives. With the increased availability of MOSFET's and IGBT's, PWM converters can be used efficiently in low and medium power applications. From the simulation studies, it is seen that the PWM AC chopper has a better harmonic spectrum and lesser copper loss than the Phase controlled AC chopper. It is observed that the drive system with the proposed model produces better dynamic performance, reduced overshoot and fast transient response. .

  1. Strongly nonlinear dynamics of electrolytes in large ac voltages

    DEFF Research Database (Denmark)

    Olesen, Laurits Højgaard; Bazant, Martin Z.; Bruus, Henrik

    2010-01-01

    We study the response of a model microelectrochemical cell to a large ac voltage of frequency comparable to the inverse cell relaxation time. To bring out the basic physics, we consider the simplest possible model of a symmetric binary electrolyte confined between parallel-plate blocking electrodes...... in the electrolyte near the electrodes and, at very large voltage, the breakdown of the quasiequilibrium structure of the double layers. The former leads to the prediction of “ac capacitive desalination” since there is a time-averaged transfer of salt from the bulk to the double layers, via oscillating diffusion...... nonlinear responses to large ac voltages, such as Faradaic reactions, electro-osmotic instabilities, and induced-charge electrokinetic phenomena....

  2. Structural, ac conductivity and dielectric properties of 3-formyl chromone

    Science.gov (United States)

    Ali, H. A. M.

    2017-07-01

    The structure for the powder of 3-formyl chromone was examined by X-ray diffraction technique in the 2θ° range ( 4° - 60° . The configuration of Al/3-formyl chromone/Al samples was designed. The electrical and dielectric properties were studied as a function of frequency (42- 5 × 106 Hz) and temperature (298-408K). The ac conductivity data of bulk of 3-formyl chromone varies as a power law with the frequency at different temperatures. The predominant mechanism for ac conduction was deduced. The ac conductivity shows a thermally activated process at different frequencies. The dielectric constant and dielectric loss were determined using the capacitance and dissipation factor measurements at different temperatures. The dielectric loss shows a peak of relaxation time that shifted to higher frequency with an increase in the temperature. The activation energy of the relaxation process was estimated.

  3. Reliability of emergency ac power systems at nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Battle, R E; Campbell, D J

    1983-07-01

    Reliability of emergency onsite ac power systems at nuclear power plants has been questioned within the Nuclear Regulatory Commission (NRC) because of the number of diesel generator failures reported by nuclear plant licensees and the reactor core damage that could result from diesel failure during an emergency. This report contains the results of a reliability analysis of the onsite ac power system, and it uses the results of a separate analysis of offsite power systems to calculate the expected frequency of station blackout. Included is a design and operating experience review. Eighteen plants representative of typical onsite ac power systems and ten generic designs were selected to be modeled by fault trees. Operating experience data were collected from the NRC files and from nuclear plant licensee responses to a questionnaire sent out for this project.

  4. Recurrent Security Gaps In 802.11ac Routers

    Directory of Open Access Journals (Sweden)

    Mohammed Farik

    2015-08-01

    Full Text Available Abstract In comparison to earlier IEEE 802.11 standard abgn routers todays popular 802.11ac standard routers have enhanced security. However 802.11ac router still has major security vulnerabilities. The novelty of this paper is that we not only highlight multiple security vulnerabilities in 802.11ac router technologies that still have not been secured since the earlier standards but also present some new ideas with solutions. We believe that our line of thoughts on security vulnerabilities gaps and on new solutions will provide network security researchers router manufacturers and network administrators with new disclosures to redesign even better security mechanisms in routers to counter attacks on networks via routers.

  5. Harmonic-free line-commutated ac/dc rectifiers

    Energy Technology Data Exchange (ETDEWEB)

    Villablanca, Miguel E. [Electrical Engineering Department, University of Santiago, P.O. Box 10233, Santiago (Chile)

    2009-11-15

    In this paper both a method and apparatus are applied to different configurations of line-commutated ac/dc rectifiers to reduce the distortion of currents flowing from the ac supply. The load may be either inductive or capacitive. The technology involves an accurate shaping of the dc current by using two self-commutated switches. This dc-current shaping is reflected back into the shaping of the ac input currents, which become pure sine waves. Thyristor-based rectifying operation is possible with a simple control circuit, which is able to deal with both rapid load variations and failures in the self-commutated switches. Furthermore, the overlap conduction of bridge thyristors is eliminated completely. Experimental verification is provided from a 400-V 30-kVA 50-Hz laboratory prototype. (author)

  6. Hydrogen sulfide releasing aspirin, ACS14, attenuates high glucose-induced increased methylglyoxal and oxidative stress in cultured vascular smooth muscle cells.

    Science.gov (United States)

    Huang, Qian; Sparatore, Anna; Del Soldato, Piero; Wu, Lingyun; Desai, Kaushik

    2014-01-01

    Hydrogen sulfide is a gasotransmitter with vasodilatory and anti-inflammatory properties. Aspirin is an irreversible cyclooxygenase inhibitor anti-inflammatory drug. ACS14 is a novel synthetic hydrogen sulfide releasing aspirin which inhibits cyclooxygenase and has antioxidant effects. Methylglyoxal is a chemically active metabolite of glucose and fructose, and a major precursor of advanced glycation end products formation. Methylglyoxal is harmful when produced in excess. Plasma methylglyoxal levels are significantly elevated in diabetic patients. Our aim was to investigate the effects of ACS14 on methylglyoxal levels in cultured rat aortic vascular smooth muscle cells. We used cultured rat aortic vascular smooth muscle cells for the study. Methylglyoxal was measured by HPLC after derivatization, and nitrite+nitrate with an assay kit. Western blotting was used to determine NADPH oxidase 4 (NOX4) and inducible nitric oxide synthase (iNOS) protein expression. Dicholorofluorescein assay was used to measure oxidative stress. ACS14 significantly attenuated elevation of intracellular methylglyoxal levels caused by incubating cultured vascular smooth muscle cells with methylglyoxal (30 µM) and high glucose (25 mM). ACS14, but not aspirin, caused a significant attenuation of increase in nitrite+nitrate levels caused by methylglyoxal or high glucose. ACS14, aspirin, and sodium hydrogen sulfide (NaHS, a hydrogen sulfide donor), all attenuated the increase in oxidative stress caused by methylglyoxal and high glucose in cultured cells. ACS14 prevented the increase in NOX4 expression caused by incubating the cultured VSMCs with MG (30 µM). ACS14, aspirin and NaHS attenuated the increase in iNOS expression caused by high glucose (25 mM). In conclusion, ACS14 has the novel ability to attenuate an increase in methylglyoxal levels which in turn can reduce oxidative stress, decrease the formation of advanced glycation end products and prevent many of the known deleterious effects

  7. Hydrogen sulfide releasing aspirin, ACS14, attenuates high glucose-induced increased methylglyoxal and oxidative stress in cultured vascular smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Qian Huang

    Full Text Available Hydrogen sulfide is a gasotransmitter with vasodilatory and anti-inflammatory properties. Aspirin is an irreversible cyclooxygenase inhibitor anti-inflammatory drug. ACS14 is a novel synthetic hydrogen sulfide releasing aspirin which inhibits cyclooxygenase and has antioxidant effects. Methylglyoxal is a chemically active metabolite of glucose and fructose, and a major precursor of advanced glycation end products formation. Methylglyoxal is harmful when produced in excess. Plasma methylglyoxal levels are significantly elevated in diabetic patients. Our aim was to investigate the effects of ACS14 on methylglyoxal levels in cultured rat aortic vascular smooth muscle cells. We used cultured rat aortic vascular smooth muscle cells for the study. Methylglyoxal was measured by HPLC after derivatization, and nitrite+nitrate with an assay kit. Western blotting was used to determine NADPH oxidase 4 (NOX4 and inducible nitric oxide synthase (iNOS protein expression. Dicholorofluorescein assay was used to measure oxidative stress. ACS14 significantly attenuated elevation of intracellular methylglyoxal levels caused by incubating cultured vascular smooth muscle cells with methylglyoxal (30 µM and high glucose (25 mM. ACS14, but not aspirin, caused a significant attenuation of increase in nitrite+nitrate levels caused by methylglyoxal or high glucose. ACS14, aspirin, and sodium hydrogen sulfide (NaHS, a hydrogen sulfide donor, all attenuated the increase in oxidative stress caused by methylglyoxal and high glucose in cultured cells. ACS14 prevented the increase in NOX4 expression caused by incubating the cultured VSMCs with MG (30 µM. ACS14, aspirin and NaHS attenuated the increase in iNOS expression caused by high glucose (25 mM. In conclusion, ACS14 has the novel ability to attenuate an increase in methylglyoxal levels which in turn can reduce oxidative stress, decrease the formation of advanced glycation end products and prevent many of the known

  8. Introducing high performance distributed logging service for ACS

    Science.gov (United States)

    Avarias, Jorge A.; López, Joao S.; Maureira, Cristián; Sommer, Heiko; Chiozzi, Gianluca

    2010-07-01

    The ALMA Common Software (ACS) is a software framework that provides the infrastructure for the Atacama Large Millimeter Array and other projects. ACS, based on CORBA, offers basic services and common design patterns for distributed software. Every properly built system needs to be able to log status and error information. Logging in a single computer scenario can be as easy as using fprintf statements. However, in a distributed system, it must provide a way to centralize all logging data in a single place without overloading the network nor complicating the applications. ACS provides a complete logging service infrastructure in which every log has an associated priority and timestamp, allowing filtering at different levels of the system (application, service and clients). Currently the ACS logging service uses an implementation of the CORBA Telecom Log Service in a customized way, using only a minimal subset of the features provided by the standard. The most relevant feature used by ACS is the ability to treat the logs as event data that gets distributed over the network in a publisher-subscriber paradigm. For this purpose the CORBA Notification Service, which is resource intensive, is used. On the other hand, the Data Distribution Service (DDS) provides an alternative standard for publisher-subscriber communication for real-time systems, offering better performance and featuring decentralized message processing. The current document describes how the new high performance logging service of ACS has been modeled and developed using DDS, replacing the Telecom Log Service. Benefits and drawbacks are analyzed. A benchmark is presented comparing the differences between the implementations.

  9. Modeling and Correcting the Time-Dependent ACS PSF

    Science.gov (United States)

    Rhodes, Jason; Massey, Richard; Albert, Justin; Taylor, James E.; Koekemoer, Anton M.; Leauthaud, Alexie

    2006-01-01

    The ability to accurately measure the shapes of faint objects in images taken with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope (HST) depends upon detailed knowledge of the Point Spread Function (PSF). We show that thermal fluctuations cause the PSF of the ACS Wide Field Camera (WFC) to vary over time. We describe a modified version of the TinyTim PSF modeling software to create artificial grids of stars across the ACS field of view at a range of telescope focus values. These models closely resemble the stars in real ACS images. Using 10 bright stars in a real image, we have been able to measure HST s apparent focus at the time of the exposure. TinyTim can then be used to model the PSF at any position on the ACS field of view. This obviates the need for images of dense stellar fields at different focus values, or interpolation between the few observed stars. We show that residual differences between our TinyTim models and real data are likely due to the effects of Charge Transfer Efficiency (CTE) degradation. Furthermore, we discuss stochastic noise that is added to the shape of point sources when distortion is removed, and we present MultiDrizzle parameters that are optimal for weak lensing science. Specifically, we find that reducing the MultiDrizzle output pixel scale and choosing a Gaussian kernel significantly stabilizes the resulting PSF after image combination, while still eliminating cosmic rays/bad pixels, and correcting the large geometric distortion in the ACS. We discuss future plans, which include more detailed study of the effects of CTE degradation on object shapes and releasing our TinyTim models to the astronomical community.

  10. Communication through Plasma Sheaths

    CERN Document Server

    Korotkevich, A O; Zakharov, V E

    2007-01-01

    We wish to transmit messages to and from a hypersonic vehicle around which a plasma sheath has formed. For long distance transmission, the signal carrying these messages must be necessarily low frequency, typically 2 GHz, to which the plasma sheath is opaque. The idea is to use the plasma properties to make the plasma sheath appear transparent.

  11. Study of AC/RF properties of SRF ingot niobium

    Energy Technology Data Exchange (ETDEWEB)

    Dhakal, Pashupati; Tsindlekht, Menachem I; Genkin, Valery M; Ciovati, Gianluigi; Myneni, Ganapati Rao

    2013-09-01

    In an attempt to correlate the performance of superconducting radiofrequency cavities made of niobium with the superconducting properties, we present the results of the magnetization and ac susceptibility of the niobium used in the superconducting radiofrequency cavity fabrication. The samples were subjected to buffer chemical polishing (BCP) surface and high temperature heat treatments, typically applied to the cavities fabrications. The analysis of the results show the different surface and bulk ac conductivity for the samples subjected to BCP and heat treatment. Furthermore, the RF surface impedance is measured on the sample using a TE011 microwave cavity for a comparison to the low frequency measurements.

  12. Power converters and AC electrical drives with linear neural networks

    CERN Document Server

    Cirrincione, Maurizio

    2012-01-01

    The first book of its kind, Power Converters and AC Electrical Drives with Linear Neural Networks systematically explores the application of neural networks in the field of power electronics, with particular emphasis on the sensorless control of AC drives. It presents the classical theory based on space-vectors in identification, discusses control of electrical drives and power converters, and examines improvements that can be attained when using linear neural networks. The book integrates power electronics and electrical drives with artificial neural networks (ANN). Organized into four parts,

  13. Development of an AC Module System: Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Suparna Kadam; Miles Russell

    2012-06-15

    The GreenRay Inc. program focused on simplifying solar electricity and making it affordable and accessible to the mainstream population. This was accomplished by integrating a solar module, micro-inverter, mounting and monitoring into a reliable, 'plug and play' AC system for residential rooftops, offering the following advantages: (1) Reduced Cost: Reduction in installation labor with fewer components, faster mounting, faster wiring. (2) Maximized Energy Production: Each AC Module operates at its maximum, reducing overall losses from shading, mismatch, or module downtime. (3) Increased Safety. Electrical and fire safety experts agree that AC Modules have significant benefits, with no energized wiring or live connections during installation, maintenance or emergency conditions. (4) Simplified PV for a Broader Group of Installers. Dramatic simplification of design and installation of a solar power system, enabling faster and more efficient delivery of the product into the market through well-established, mainstream channels. This makes solar more accessible to the public. (5) Broadened the Rooftop Market: AC Modules enable solar for many homes that have shading, split roofs, or obstructions. In addition, due to the smaller building block size of 200W vs. 1000W, homeowners with budget limitations can start small and add to their systems over time. Through this DOE program GreenRay developed the all-in-one AC Module system with an integrated PV Module and microinverter, custom residential mounting and performance monitoring. Development efforts took the product from its initial concept, through prototypes, to a commercial product sold and deployed in the residential market. This pilot deployment has demonstrated the technical effectiveness of the AC Module system in meeting the needs and solving the problems of the residential market. While more expensive than the traditional central inverter systems at the pilot scale, the economics of AC Modules become

  14. Productos «Celotex» para acondicionamientos Acústicos

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1958-02-01

    Full Text Available Not availableBajo la denominación general «Celotex», que es un nombre registrado, la Casa Americana The Celotex Corporation, cuyo domicilio social es 120 South, La Salle Street, Chicago J. lllinois, fabrica diversos materiales para fines de acondicionamiento acústico elaborados, según los tipos de que se trate, con fibra de caña de azúcar, lanas minerales, acero, amianto, etc., perforados o no y de acuerdo con el efecto estético y acústico que se desee obtener.

  15. AC and Phase Sensing of Nanowires for Biosensing.

    Science.gov (United States)

    Crescentini, Marco; Rossi, Michele; Ashburn, Peter; Lombardini, Marta; Sangiorgi, Enrico; Morgan, Hywel; Tartagni, Marco

    2016-04-19

    Silicon nanowires are label-free sensors that allow real-time measurements. They are economical and pave the road for point-of-care applications but require complex readout and skilled personnel. We propose a new model and technique for sensing nanowire sensors using alternating currents (AC) to capture both magnitude and phase information from the sensor. This approach combines the advantages of complex impedance spectroscopy with the noise reduction performances of lock-in techniques. Experimental results show how modifications of the sensors with different surface chemistries lead to the same direct-current (DC) response but can be discerned using the AC approach.

  16. Development of an AC Module System: Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Suparna Kadam; Miles Russell

    2012-06-15

    The GreenRay Inc. program focused on simplifying solar electricity and making it affordable and accessible to the mainstream population. This was accomplished by integrating a solar module, micro-inverter, mounting and monitoring into a reliable, 'plug and play' AC system for residential rooftops, offering the following advantages: (1) Reduced Cost: Reduction in installation labor with fewer components, faster mounting, faster wiring. (2) Maximized Energy Production: Each AC Module operates at its maximum, reducing overall losses from shading, mismatch, or module downtime. (3) Increased Safety. Electrical and fire safety experts agree that AC Modules have significant benefits, with no energized wiring or live connections during installation, maintenance or emergency conditions. (4) Simplified PV for a Broader Group of Installers. Dramatic simplification of design and installation of a solar power system, enabling faster and more efficient delivery of the product into the market through well-established, mainstream channels. This makes solar more accessible to the public. (5) Broadened the Rooftop Market: AC Modules enable solar for many homes that have shading, split roofs, or obstructions. In addition, due to the smaller building block size of 200W vs. 1000W, homeowners with budget limitations can start small and add to their systems over time. Through this DOE program GreenRay developed the all-in-one AC Module system with an integrated PV Module and microinverter, custom residential mounting and performance monitoring. Development efforts took the product from its initial concept, through prototypes, to a commercial product sold and deployed in the residential market. This pilot deployment has demonstrated the technical effectiveness of the AC Module system in meeting the needs and solving the problems of the residential market. While more expensive than the traditional central inverter systems at the pilot scale, the economics of AC Modules become

  17. Active Power Regulation based on Droop for AC Microgrid

    DEFF Research Database (Denmark)

    Li, Chendan; Coelho, Ernane A. A.; Firoozabadi, Mehdi Savaghebi

    2015-01-01

    In this paper, two different control strategies are proposed to address the active power regulation issue in AC microgrids. The principle of power regulation in the droop controller is firstly introduced. Frequency scheduling and droop gain scheduling on top of droop control is proposed to succes......In this paper, two different control strategies are proposed to address the active power regulation issue in AC microgrids. The principle of power regulation in the droop controller is firstly introduced. Frequency scheduling and droop gain scheduling on top of droop control is proposed...

  18. System and method for determining stator winding resistance in an AC motor using motor drives

    Science.gov (United States)

    Lu, Bin; Habetler, Thomas G; Zhang, Pinjia

    2013-02-26

    A system and method for determining the stator winding resistance of AC motors is provided. The system includes an AC motor drive having an input connectable to an AC source and an output connectable to an input terminal of an AC motor, a pulse width modulation (PWM) converter having switches therein to control current flow and terminal voltages in the AC motor, and a control system connected to the PWM converter. The control system generates a command signal to cause the PWM converter to control an output of the AC motor drive corresponding to an input to the AC motor, selectively generates a modified command signal to cause the PWM converter to inject a DC signal into the output of the AC motor drive, and determines a stator winding resistance of the AC motor based on the DC signal of at least one of the voltage and current.

  19. Biocompatible Silver-containing a-C:H and a-C coatings: AComparative Study

    Energy Technology Data Exchange (ETDEWEB)

    Endrino, Jose Luis; Allen, Matthew; Escobar Galindo, Ramon; Zhang, Hanshen; Anders, Andre; Albella, Jose Maria

    2007-04-01

    Hydrogenated diamond-like-carbon (a-C:H) and hydrogen-free amorphous carbon (a-C) coatings are known to be biocompatible and have good chemical inertness. For this reason, both of these materials are strong candidates to be used as a matrix that embeds metallic elements with antimicrobial effect. In this comparative study, we have incorporated silver into diamond-like carbon (DLC) coatings by plasma based ion implantation and deposition (PBII&D) using methane (CH4) plasma and simultaneously depositing Ag from a pulsed cathodic arc source. In addition, we have grown amorphous carbon - silver composite coatings using a dual-cathode pulsed filtered cathodic-arc (FCA) source. The silver atomic content of the deposited samples was analyzed using glow discharge optical spectroscopy (GDOES). In both cases, the arc pulse frequency of the silver cathode was adjusted in order to obtain samples with approximately 5 at.% of Ag. Surface hardness of the deposited films was analyzed using the nanoindentation technique. Cell viability for both a-C:H/Ag and a-C:/Ag samples deposited on 24-well tissue culture plates has been evaluated.

  20. 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

  1. 升降式交流斩波器%Buck-Boost AC/AC Direct Converter

    Institute of Scientific and Technical Information of China (English)

    孙刚; 洪峰

    2009-01-01

    介绍了一种新颖的Buck-Boost型交流斩波器.该交流斩波器将Buck-Boost型DC/DC变换器的开关管双向化,可实现单级降压或升压的AC/AC直接变换和能量双向流动.该变换器使用较少的功率器件实现了单级功率变换和能量双向流动,有利于提高变换器的功率密度和变换效率.详细研究了其工作模态和原理.分析了该变换器的两种PWM调制策略,并指出采用第2种调制策略可降低开关损耗.采用滞环电流控制的Buck/Boost型交流斩波器可对输入电压畸变进行有效抑制,保持了输出电压波形的高度正弦化.仿真和实验验证了分析的正确性.

  2. Collisionless plasmas in astrophysics

    CERN Document Server

    Belmont, Gerard; Mottez, Fabrice; Pantellini, Filippo; Pelletier, Guy

    2013-01-01

    Collisionless Plasmas in Astrophysics examines the unique properties of media without collisions in plasma physics. Experts in this field, the authors present the first book to concentrate on collisionless conditions in plasmas, whether close or not to thermal equilibrium. Filling a void in scientific literature, Collisionless Plasmas in Astrophysics explains the possibilities of modeling such plasmas, using a fluid or a kinetic framework. It also addresses common misconceptions that even professionals may possess, on phenomena such as "collisionless (Landau) damping". Abundant illustrations

  3. Deposition of hybrid organic-inorganic composite coatings using an atmospheric plasma jet system.

    Science.gov (United States)

    Dembele, Amidou; Rahman, Mahfujur; Reid, Ian; Twomey, Barry; MacElroy, J M Don; Dowling, Denis P

    2011-10-01

    The objective of this study is to investigate the influence of alcohol addition on the incorporation of metal oxide nanoparticles into nm thick siloxane coatings. Titanium oxide (TiO2) nanoparticles with diameters of 30-80 nm were incorporated into an atmospheric plasma deposited tetramethylorthosilicate (TMOS) siloxane coating. The TMOS/TiO2 coating was deposited using the atmospheric plasma jet system known as PlasmaStream. In this system the liquid precursor/nanoparticle mixture is nebulised into the plasma. It was observed that prior to being nebulised the TiO2 particles agglomerated and settled over time in the TMOS/TiO2 mixture. In order to obtain a more stable nanoparticle/TMOS suspension the addition of the alcohols methanol, octanol and pentanol to this mixture was investigated. The addition of each of these alcohols was found to stabilise the nanoparticle suspension. The effect of the alcohol was therefore assessed with respect to the properties of the deposited coatings. It was observed that coatings deposited from TMOS/TiO2, with and without the addition of methanol were broadly similar. In contrast the coatings deposited with octanol and pentanol addition to the TMOS/TiO2 mixture were significantly thicker, for a given set of deposition parameters and were also more homogeneous. This would indicate that the alcohol precursor was incorporated into the plasma polymerised siloxane. The incorporation of the organic functionality from the alcohols was confirmed from FTIR spectra of the coatings. The difference in behaviour with alcohol type is likely to be due to the lower boiling point of methanol (65 degrees C), which is lower than the maximum plasma temperature measured at the jet orifice (77 degrees C). This temperature is significantly lower than the 196 degrees C and 136 degrees C boiling points of octanol and pentanol respectively. The friction of the coatings was determined using the Pin-on-disc technique. The more organic coatings deposited with

  4. Impacts on Power Factor of AC Voltage Controllers Under Non-Sinusoidal Conditions

    Directory of Open Access Journals (Sweden)

    Mukhtiar Ahmed Mahar

    2012-04-01

    Full Text Available AC-AC conversion is obtained with the help of Cyclo-converters, DC Link converters and AC Voltage Controllers. AC voltage controllers are also referred to as voltage regulators. Main issue concerned to these converters is that they generate harmonics due to periodic variable structure system. The generated harmonics create disturbances and degrade the performance of converter. The power factor of supply side is affected due to these harmonics. This paper focuses on source side power factor of ac voltage controllers under nonsinusoidal conditions. In order to observe the power factor, measurement tool of power factor and simulation model of ac voltage controller is also developed in MATLAB software.

  5. Modulation schemes with enhanced switch thermal distribution for single-phase AC-DC-AC reduced-switch converters

    DEFF Research Database (Denmark)

    Qin, Zian; Loh, Poh Chiang; Blaabjerg, Frede

    2015-01-01

    ulation schemes can significantly change the performance of a power converter in steady state, and they have been extensively studied, but mostly directed to three-phase topologies, where triplen offsets are added. Single-phase systems, including ac-dc-ac systems, are less widely pursued, even...... among their switches, while keeping their dc-link voltages low. Single points of failure are thus minimized, allowing the converters to have longer lifetimes. Simulation and experimental results have demonstrated the intended performances and hence verifying the idea....

  6. Two very long chain fatty acid acyl-CoA synthetase genes, acs-20 and acs-22, have roles in the cuticle surface barrier in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Eriko Kage-Nakadai

    Full Text Available In multicellular organisms, the surface barrier is essential for maintaining the internal environment. In mammals, the barrier is the stratum corneum. Fatty acid transport protein 4 (FATP4 is a key factor involved in forming the stratum corneum barrier. Mice lacking Fatp4 display early neonatal lethality with features such as tight, thick, and shiny skin, and a defective skin barrier. These symptoms are strikingly similar to those of a human skin disease called restrictive dermopathy. FATP4 is a member of the FATP family that possesses acyl-CoA synthetase activity for very long chain fatty acids. How Fatp4 contributes to skin barrier function, however, remains to be elucidated. In the present study, we characterized two Caenorhabditis elegans genes, acs-20 and acs-22, that are homologous to mammalian FATPs. Animals with mutant acs-20 exhibited defects in the cuticle barrier, which normally prevents the penetration of small molecules. acs-20 mutant animals also exhibited abnormalities in the cuticle structure, but not in epidermal cell fate or cell integrity. The acs-22 mutants rarely showed a barrier defect, whereas acs-20;acs-22 double mutants had severely disrupted barrier function. Moreover, the barrier defects of acs-20 and acs-20;acs-22 mutants were rescued by acs-20, acs-22, or human Fatp4 transgenes. We further demonstrated that the incorporation of exogenous very long chain fatty acids into sphingomyelin was reduced in acs-20 and acs-22 mutants. These findings indicate that C. elegans Fatp4 homologue(s have a crucial role in the surface barrier function and this model might be useful for studying the fundamental molecular mechanisms underlying human skin barrier and relevant diseases.

  7. BOLD signal effects of transcranial alternating current stimulation (tACS) in the alpha range: A concurrent tACS-fMRI study.

    Science.gov (United States)

    Vosskuhl, Johannes; Huster, René J; Herrmann, Christoph S

    2016-10-15

    Many studies have proven transcranial alternating current stimulation (tACS) to manipulate brain activity. Until now it is not known, however, how these manipulations in brain activity are represented in brain metabolism or how spatially specific these changes are. Alpha-tACS has been shown to enhance the amplitude of the individual alpha frequency (IAF) and a negative correlation between alpha amplitude and occipital BOLD signal was reported in numerous EEG/fMRI experiments. Thus, alpha-tACS was chosen to test the effects of tACS on the BOLD signal. A reduction thereof was expected during alpha-tACS which shows the spatial extent of tACS effects beyond modeling studies. Three groups of subjects were measured in an MRI scanner, receiving tACS at either their IAF (N=11), 1Hz (control; N=12) or sham (i.e., no stimulation - a second control; N=11) while responding to a visual vigilance task. Stimulation was administered in an interleaved pattern of tACS-on runs and tACS-free baseline periods. The BOLD signal was analyzed in response to tACS-onset during resting state and in response to seldom target stimuli. Alpha-tACS at 1.0mA reduced the task-related BOLD response to visual targets in the occipital cortex as compared to tACS-free baseline periods. The deactivation was strongest in an area where the BOLD signal was shown to correlate negatively with alpha amplitude. A direct effect of tACS on resting state BOLD signal levels could not be shown. Our findings suggest that tACS-related changes in BOLD activity occur only as a modulation of an existing BOLD response.

  8. Colloidal Plasmas : Basic physics of colloidal plasmas

    Indian Academy of Sciences (India)

    C B Dwivedi

    2000-11-01

    Colloidal plasma is a distinct class of the impure plasmas with multispecies ionic composition. The distinction lies in the phase distribution of the impurity-ion species. The ability to tailor the electrostatic interactions between these colloidal particles provides a fertile ground for scientists to investigate the fundamental aspects of the Coulomb phase transition behavior. The present contribution will review the basic physics of the charging mechanism of the colloidal particles as well as the physics of the collective normal mode behavior of the general multi-ion species plasmas. Emphasis will be laid on the clarification of the prevailing confusing ideas about distinct qualities of the various acoustic modes, which are likely to exist in colloidal plasmas as well as in normal multi-ion species plasmas. Introductory ideas about the proposed physical models for the Coulomb phase transition in colloidal plasma will also be discussed.

  9. Equivalent Circuits For AC-Impedance Analysis Of Corrosion

    Science.gov (United States)

    Danford, M. D.

    1992-01-01

    Report presents investigation of equivalent circuits for ac-impedance analysis of corrosion. Impedance between specimen and electrolyte measured as function of frequency. Data used to characterize corrosion electrochemical system in terms of equivalent circuit. Eleven resistor/capacitor equivalent-circuit models were analyzed.

  10. harmonics: generation and suppression in ac system networks

    African Journals Online (AJOL)

    2012-11-03

    Nov 3, 2012 ... HARMONICS: GENERATION AND SUPPRESSION IN AC. SYSTEM NETWORKS .... If Vs = 295V; Z = (8 + j6)Ω and δ = 2π/3, the output voltage, Vo and ... tor current assume the characteristics shown in figure. 8. The output ...

  11. Current Control of Grid Converters Connected with Series AC Capacitor

    DEFF Research Database (Denmark)

    Wang, Xiongfei; Blaabjerg, Frede; Loh, Poh Chiang

    2015-01-01

    The series ac capacitor has recently been used with the transformerless grid-connected converters in the distribution power grids. The capacitive characteristic of the resulting series LC filter restricts the use of conventional synchronous integral or stationary resonant current controllers. Thus...

  12. Calculation of AC losses in large HTS stacks and coils

    DEFF Research Database (Denmark)

    Zermeno, Victor; Abrahamsen, Asger Bech; Mijatovic, Nenad;

    2012-01-01

    In this work, we present a homogenization method to model a stack of HTS tapes under AC applied transport current or magnetic field. The idea is to find an anisotropic bulk equivalent for the stack of tapes, where the internal alternating structures of insulating, metallic, superconducting and su...

  13. Novel dielectric reduces corona breakdown in ac capacitors

    Science.gov (United States)

    Loehner, J. L.

    1972-01-01

    Dielectric system was developed which consists of two layers of 25-gage paper separated by one layer of 50-gage polypropylene to reduce corona breakdown in ac capacitors. System can be used in any alternating current application where constant voltage does not exceed 400 V rms. With a little research it could probably be increased to 700 to 800 V rms.

  14. Dielectric relaxation and ac conductivity of sodium tungsten phosphate glasses

    Indian Academy of Sciences (India)

    B Singh; P S Tarsikka; L Singh

    2002-10-01

    Studies of dielectric relaxation and ac conductivity have been made on three samples of sodium tungsten phosphate glasses over a temperature range of 77–420 K. Complex relative permittivity data have been analyzed using dielectric modulus approach. Conductivity relaxation frequency increases with the increase of temperature. Activation energy for conductivity relaxation has also been evaluated. Measured ac conductivity (m()) has been found to be higher than dc at low temperatures whereas at high temperature m() becomes equal to dc at all frequencies. The ac conductivity obeys the relation ac() = A over a considerable range of low temperatures. Values of exponent are nearly equal to unity at about 78 K and the values decrease non-linearly with the increase of temperature. Values of the number density of states at Fermi level ((F)) have been evaluated at 80 K assuming values of electron wave function decay constant to be 0.5 (Å)-1. Values of (F) have the order 1020 which are well within the range suggested for localized states. Present values of (F) are smaller than those for tungsten phosphate glasses.

  15. Heat Transfer Analysis for Industrial AC Electric Arc Furnace

    Institute of Scientific and Technical Information of China (English)

    (U)nal (C)amdali; Murat Tun(c)

    2005-01-01

    The heat transfer analysis was performed for an AC electric arc furnace (EAF). Heat losses by conduction, convection and radiation from outer surface, roof, bottom and electrodes of EAF were determined in detail. Some suggestions about decreasing heat losses were presented.

  16. 7 CFR 1737.31 - Area Coverage Survey (ACS).

    Science.gov (United States)

    2010-01-01

    ... Design. (Approved by the Office of Management and Budget under control number 0572-0079) ... Survey (ACS) is a market forecast of service requirements of subscribers in a proposed service area. (b... identification of future establishments are also recorded on the maps. (2) A forecast of the number of...

  17. Introducing AC Inductive Reactance with a Power Tool

    Science.gov (United States)

    Bryant, Wesley; Baker, Blane

    2016-01-01

    The concept of reactance in AC electrical circuits is often non-intuitive and difficult for students to grasp. In order to address this lack of conceptual understanding, classroom exercises compare the predicted resistance of a power tool, based on electrical specifications, to measured resistance. Once students discover that measured resistance…

  18. A simple technique for a.c. conductivity measurements

    Indian Academy of Sciences (India)

    R Padma Suvarna; K Raghavendra Rao; K Subbarangaiah

    2002-12-01

    An inexpensive, indigenous and a simple electronic instrument based on voltage follower, current–to–voltage converter, zero crossing detector and a phase detector has been developed for measurement of a.c. conductivity. Real and imaginary parts of complex impedance are determined for a given sample as a function of frequency and the given sample is represented by a pure electronic model.

  19. Rethinking Rectification: AC-DC Power Supply in Package

    DEFF Research Database (Denmark)

    Pejtersen, Jens; Knott, Arnold; Jørgensen, Ivan Harald Holger

    Rectification of AC mains voltage is almost exclusively implemented with passive diode bridge rectifiers for power applications below 100 W. The diode bridge rectifier is reliable, cost effective and easy to use. But it is also lossy, nonlinear and passive. Thus reducing the power conversion...

  20. 78 FR 42567 - ACS Wireless, Inc.; Notice of Application

    Science.gov (United States)

    2013-07-16

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION ACS Wireless, Inc.; Notice of Application June 25, 2013. Correction In notice document 2013-15658 beginning on page 39345 in the issue of Monday, July 1, 2013, make the following correction: On page...

  1. Soliton ratchetlike dynamics by ac forces with harmonic mixing

    DEFF Research Database (Denmark)

    Salerno, Mario; Zolotaryuk, Yaroslav

    2002-01-01

    The possibility of unidirectional motion of a kink (topological soliton) of a dissipative sine-Gordon equation in the presence of ac forces with harmonic mixing (at least biharmonic) and of zero mean, is presented. The dependence of the kink mean velocity on system parameters is investigated...

  2. Stretched exponential relaxation and ac universality in disordered dielectrics

    DEFF Research Database (Denmark)

    Milovanov, Alexander V.; Rypdal, Kristoffer; Juul Rasmussen, Jens

    2007-01-01

    This paper is concerned with the connection between the properties of dielectric relaxation and alternating-current (ac) conduction in disordered dielectrics. The discussion is divided between the classical linear-response theory and a self-consistent dynamical modeling. The key issues are stretc......This paper is concerned with the connection between the properties of dielectric relaxation and alternating-current (ac) conduction in disordered dielectrics. The discussion is divided between the classical linear-response theory and a self-consistent dynamical modeling. The key issues...... are stretched exponential character of dielectric relaxation, power-law power spectral density, and anomalous dependence of ac conduction coefficient on frequency. We propose a self-consistent model of dielectric relaxation in which the relaxations are described by a stretched exponential decay function....... Mathematically, our study refers to the expanding area of fractional calculus and we propose a systematic derivation of the fractional relaxation and fractional diffusion equations from the property of ac universality....

  3. Study of ac electrical properties of aluminium-epoxy composites

    Energy Technology Data Exchange (ETDEWEB)

    Elimat, Z M [Applied Science Department, Ajloun University College, Al-Balqa Applied University, Amman (Jordan); Zihlif, A M [Physics Department, University of Jordan, Amman (Jordan); Ragosta, G [Institute of Chemistry and Polymer Technology (ICTP), CNR-Possouli, Napoli (Italy)], E-mail: adzh@ju.edu.jo

    2008-08-21

    Ac electrical properties of aluminium flakes-epoxy composites were studied as a function of the composition, frequency and temperature. The dielectric constant increased smoothly with an increase in the concentration of aluminium. An increase in the dielectric constant was observed with the temperature as well as with a decrease in the frequency. The observed increase in the values of the dielectric constant with the aluminium concentration was attributed to interfacial polarization. It was found that ac electrical conductivity increases with increasing content of aluminium, temperature and frequency. The observed enhancement in ac conductivity is attributed to the increase in the number of conduction paths created by the aluminium flake contacts in the composite to give a higher electrical conductivity. Also, the activation energy of aluminium flakes-epoxy composites was determined, as well as the values of the dielectric constant. Compared with various theoretical models, Bruggman's formula gives a better fit. The universal power-law model of ac conductivity is observed in epoxy-aluminium composites. The calculated power exponent (about unity) is physically acceptable within this applied model.

  4. Recommended ACS Syllabus for Introductory Courses in Polymer Chemistry.

    Science.gov (United States)

    Seymour, Raymond B.

    1982-01-01

    Provides syllabus for courses in introductory polymer chemistry (including major topics and recommended time allotments) and currently available textbooks and audio courses which may be used with the syllabus. Syllabus topics are congruent with those used in American Chemical Society (ACS) standardized examination in polymer chemistry. (Author/JN)

  5. An overview of the ALMA Common Software (ACS) .

    Science.gov (United States)

    Di Marcantonio, P.; Cirami, R.; Caproni, A.; Chiozzi, G.; Jeram, B.; Sommer, H.; Harrington, S.; Zagar, K.; Plesko, M.; Sekoranja, M.

    The ALMA Common Software (ACS) is an application framework designed to provide a common and homogeneous software architecture and infrastructure, spanning the end to end needs of an Astronomical observatory, from the Telescope Control system to high-level data flow management. ACS offers, at the lower level, several basic services needed for object-oriented distributed computing like transparent remote object invocation, object deployment and location, distributed error, alarm handling, logging and events. On top of this it provides an application architecture based on the Component/Container paradigm that fosters sharing and reusing of software components. Although developed for the ALMA project, ACS is now used by several other projects worldwide, among which the Italian Sardinia Radio Telescope (SRT). Besides, there is an active community that shares ideas, concepts and actual software components. Major drivers for this diffusion were the choice of adopting the LGPL public license and the adoption of CORBA, a free but reliable and widely used middleware software. In this paper we present an overview of the main features of ACS, emphasizing in particular the role of INAF-OAT in this project.

  6. Container-component model and XML in ALMA ACS

    Science.gov (United States)

    Sommer, Heiko; Chiozzi, Gianluca; Zagar, Klemen; Voelter, Markus

    2004-09-01

    ALMA software, from high-level data flow applications down to instrument control, is built using the ACS framework. To meet the challenges of developing distributed software in distributed teams, ACS offers a container/component model that integrates the use of XML transfer objects. ACS containers are built on top of CORBA and are available for C++, Java, and Python, so that ALMA software can be written as components in any of these languages. The containers perform technical aspects of the software system, while components can focus on the implementation of functional requirements. Like Web services, components can use XML to exchange structured data by value. For Java components, the container seamlessly integrates the use of XML binding classes, which are Java classes that encapsulate access to XML data through type-safe methods. Binding classes are generated from XML schemas, allowing the Java compiler to enforce compliance of application code with the XML schemas. This presentation will explain the capabilities of the ACS container/component model, and how it relates to other middleware technologies that are popular in industry.

  7. Phase controlled dc-ac converter with high frequency switching

    Science.gov (United States)

    Harada, Koosuke; Sakamoto, Hiroshi; Shoyama, Masahito

    A sinusoidal dc-ac converter is presented in which a pair of switches is placed on each side of the primary and secondary of the isolation transformer. This converter is controlled by the phase difference between the two pairs of switches. The transformer is miniaturized by making the switching frequency high. This converter is especially suitable for small uninterruptible power supply systems.

  8. Acústica, fluidos y termodinámica

    OpenAIRE

    Beléndez Vázquez, Augusto

    1992-01-01

    Acústica. Estática de fluidos. Dinámica de fluidos y fluidos reales. Temperatura y propagación del calor. Primer principio de la Termodinámica. Gases ideales. Segundo principio de la Termodinámica.

  9. Conductivity measurements with trapezoidal a.c. magnetic fields

    NARCIS (Netherlands)

    Gijsbertse, E.A.; Klundert, van de L.J.M.

    1981-01-01

    The inductive response of normal metals to trapezoidal a.c. fields is studied theoretically as well as experimentally. A method is presented to determine the conductivity and its magnetic induction dependence from the decay of the induced voltage during periods of constant field. The correctness of

  10. The Material Plasma Exposure eXperiment (MPEX)

    Science.gov (United States)

    Rapp, J.; Biewer, T. M.; Bigelow, T. S.; Canik, J.; Caughman, J. B. O.; Duckworth, R. C.; Goulding, R. H.; Hillis, D. L.; Lore, J. D.; Lumsdaine, A.; McGinnis, W. D.; Meitner, S. J.; Owen, L. W.; Shaw, G. C.; Luo, G.-N.

    2014-10-01

    Next generation plasma generators have to be able to access the plasma conditions expected on the divertor targets in ITER and future devices. The Material Plasma Exposure eXperiment (MPEX) will address this regime with electron temperatures of 1--10 eV and electron densities of 1021--1020 m-3. The resulting heat fluxes are about 10 MW/m2. MPEX is designed to deliver those plasma conditions with a novel Radio Frequency plasma source able to produce high density plasmas and heat electron and ions separately with Electron Bernstein Wave (EBW) heating and Ion Cyclotron Resonance Heating (ICRH). Preliminary modeling has been used for pre-design studies of MPEX. MPEX will be capable to expose neutron irradiated samples. In this concept targets will be irradiated in ORNL's High Flux Isotope Reactor (HFIR) or possibly at the Spallation Neutron Source (SNS) and then subsequently (after a sufficient long cool-down period) exposed to fusion reactor relevant plasmas in MPEX. The current state of the pre-design of MPEX including the concept of handling irradiated samples will be presented. ORNL is managed by UT-Battelle, LLC, for the U.S. DOE under Contract DE-AC-05-00OR22725.

  11. Nonlinear plasma wave in magnetized plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Bulanov, Sergei V. [Kansai Photon Science Institute, JAEA, Kizugawa, Kyoto 619-0215 (Japan); Prokhorov Institute of General Physics, Russian Academy of Sciences, Moscow 119991 (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny, Moscow region 141700 (Russian Federation); Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K. [Kansai Photon Science Institute, JAEA, Kizugawa, Kyoto 619-0215 (Japan); Hosokai, Tomonao; Zhidkov, Alexei G. [Photon Pioneers Center, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871 (Japan); Japan Science and Technology Agency, CREST, 2-1, Yamadaoka, Suita, Osaka 565-0871 (Japan); Kodama, Ryosuke [Photon Pioneers Center, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2013-08-15

    Nonlinear axisymmetric cylindrical plasma oscillations in magnetized collisionless plasmas are a model for the electron fluid collapse on the axis behind an ultrashort relativisically intense laser pulse exciting a plasma wake wave. We present an analytical description of the strongly nonlinear oscillations showing that the magnetic field prevents closing of the cavity formed behind the laser pulse. This effect is demonstrated with 3D PIC simulations of the laser-plasma interaction. An analysis of the betatron oscillations of fast electrons in the presence of the magnetic field reveals a characteristic “Four-Ray Star” pattern.

  12. Biocontrol activity of Paenibacillus polymyxa AC-1 against Pseudomonas syringae and its interaction with Arabidopsis thaliana.

    Science.gov (United States)

    Hong, Chi Eun; Kwon, Suk Yoon; Park, Jeong Mee

    2016-04-01

    Paenibacillus polymyxa AC-1 (AC-1) is a plant growth-promoting rhizobacterium (PGPR) that has been used as a soil inoculant for biocontrol of plant pathogenic fungi and to promote plant growth. In this study, we examine the effects of AC-1 on the bacterial phytopathogen Pseudomonas syringae and internal colonization of AC-1 by counting bacterial populations that colonize plants. AC-1 inhibited the growth of both P. syringae pv. tomato DC3000 (Pst) and P. syringae pv. tabaci (Pta) in a concentration-dependent manner in in vitro assays. Upon treatment of AC-1 dropping at root tip of axenically grown Arabidopsis, we found that most of the AC-1 was detected in interior of leaves of Arabidiopsis plants rather than roots after 5 days post infection, indicating systemic spreading of AC-1 occur. We examined further AC-1 colonization patterns in Arabidopsis mutants deficient in phytohormone signaling pathways. These results indicated that abscisic acid (ABA) and jasmonic acid (JA) signaling pathways positively and negatively contributed, respectively, to AC-1 colonization of leaves, whereas epiphytic accumulation of AC-1 around root tissues was not affected. This study shows that AC-1 is an effective biocontrol agent to suppress P. syringae growth, possibly owing to its colonization patterns as a leaf-inhabiting endophyte. The results showed in this work will help to expand our understanding of the mode of action of AC-1 as a biological control agent and consequently, its application in agriculture.

  13. Elements of plasma technology

    CERN Document Server

    Wong, Chiow San

    2016-01-01

    This book presents some fundamental aspects of plasma technology that are important for beginners interested to start research in the area of plasma technology . These include the properties of plasma, methods of plasma generation and basic plasma diagnostic techniques. It also discusses several low cost plasma devices, including pulsed plasma sources such as plasma focus, pulsed capillary discharge, vacuum spark and exploding wire; as well as low temperature plasmas such as glow discharge and dielectric barrier discharge which the authors believe may have potential applications in industry. The treatments are experimental rather than theoretical, although some theoretical background is provided where appropriate. The principles of operation of these devices are also reviewed and discussed.

  14. Aragonite coating solutions (ACS) based on artificial seawater

    Energy Technology Data Exchange (ETDEWEB)

    Tas, A. Cuneyt, E-mail: c_tas@hotmail.com

    2015-03-01

    Graphical abstract: - Highlights: • Developed completely inorganic solutions for the deposition of monolayers of aragonite spherules (or ooids). • Solutions mimicked the artificial seawater. • Biomimetic crystallization was performed at the tropical sea surface temperature of 30 °C. - Abstract: Aragonite (CaCO{sub 3}, calcium carbonate) is an abundant biomaterial of marine life. It is the dominant inorganic phase of coral reefs, mollusc bivalve shells and the stalactites or stalagmites of geological sediments. Inorganic and initially precipitate-free aragonite coating solutions (ACS) of pH 7.4 were developed in this study to deposit monolayers of aragonite spherules or ooids on biomaterial (e.g., UHMWPE, ultrahigh molecular weight polyethylene) surfaces soaked in ACS at 30 °C. The ACS solutions of this study have been developed for the surface engineering of synthetic biomaterials. The abiotic ACS solutions, enriched with calcium and bicarbonate ions at different concentrations, essentially mimicked the artificial seawater composition and started to deposit aragonite after a long (4 h) incubation period at the tropical sea surface temperature of 30 °C. While numerous techniques for the solution deposition of calcium hydroxyapatite (Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2}), of low thermodynamic solubility, on synthetic biomaterials have been demonstrated, procedures related to the solution-based surface deposition of high solubility aragonite remained uncommon. Monolayers of aragonite ooids deposited at 30 °C on UHMWPE substrates soaked in organic-free ACS solutions were found to possess nano-structures similar to the mortar-and-brick-type botryoids observed in biogenic marine shells. Samples were characterized using SEM, XRD, FTIR, ICP-AES and contact angle goniometry.

  15. Flame spread over inclined electrical wires with AC electric fields

    KAUST Repository

    Lim, Seung J.

    2017-07-21

    Flame spread over polyethylene-insulated electrical wires was studied experimentally with applied alternating current (AC) by varying the inclination angle (θ), applied voltage (VAC), and frequency (fAC). For the baseline case with no electric field applied, the flame spread rate and the flame width of downwardly spreading flames (DSFs) decreased from the horizontal case for −20° ≤ θ < 0° and maintained near constant values for −90° ≤ θ < −20°, while the flame spread rate increased appreciably as the inclination angle of upwardly spreading flames (USFs) increased. When an AC electric field was applied, the behavior of flame spread rate in DSFs (USFs) could be classified into two (three) sub-regimes characterized by various functional dependences on VAC, fAC, and θ. In nearly all cases of DSFs, a globular molten polyethylene formed ahead of the spreading flame edge, occasionally dripping onto the ground. In these cases, an effective flame spread rate was defined to represent the burning rate by measuring the mass loss due to dripping. This effective spread rate was independent of AC frequency, while it decreased linearly with voltage and was independent of the inclination angle. In DSFs, when excessively high voltage and frequency were applied, the dripping led to flame extinction during propagation and the extinction frequency correlated well with applied voltage. In USFs, when high voltage and frequency were applied, multiple globular molten PEs formed at several locations, leading to ejections of multiple small flame segments from the main flame, thereby reducing the flame spread rate, which could be attributed to the electrospray phenomenon.

  16. Micro patterning of cell and protein non-adhesive plasma polymerized coatings for biochip applications

    DEFF Research Database (Denmark)

    Bouaidat, Salim; Berendsen, C.; Thomsen, P.;

    2004-01-01

    Micro scale patterning of bioactive surfaces is desirable for numerous biochip applications. Polyethyleneoxide-like (PEO-like) coating with non-fouling functionality has been deposited using low frequency AC plasma polymerization. The non-fouling properties of the coating were tested with human...... cells ( HeLa) and fluorescence labeled proteins (isothiocyanate-labeled bovine serum albumin, i.e. FITC-BSA). The PEO-like coatings were fabricated by plasma polymerization of 12-crown-4 (ppCrown) with plasma polymerized hexene (ppHexene) as adhesion layer. The coatings were micro patterned using...

  17. Assessment of sperm quality, oxidative stress injury as well as ACP, AC and PDE expression in patients with oligoasthenozoospermia before and after qilin pill treatment

    Institute of Scientific and Technical Information of China (English)

    Shi-Jun Zhang; Jian-Gang Kuang; Tao Ren; Peng Liu; Long Liu; Yu-Gang Liu; Zhi-Ping Lei; Ma-Long Shi

    2016-01-01

    Objective:To analyze the sperm quality, oxidative stress injury as well as ACP, AC and PDE expression in patients with oligoasthenozoospermia before and after qilin pill treatment. Methods:A total of 60 patients with oligoasthenozoospermia were randomly divided into observation group and control group, control group received routine western medicine treatment, observation group received qilin pill + conventional western medicine treatment, and then differences in sperm quality, oxidative stress injury, ACP, AC and PDE expression, etc. were compared between two groups after treatment.Results:Semen volume and sperm density in semen samples of observation group after qilin pill treatment were higher than those of control group; serum FSH and LH levels were lower than those of control group, and the T level was higher than that of control group; ROS and MDA levels in seminal plasma were lower than those of control group, and SOD level was higher than that of control group; ACP, AC, -Glu and Fru levels in seminal plasma were higher than those of control group, and PDE level was lower than that of control group.Conclusion: Qilin pill can improve sperm quality and optimize testicular internal environment in patients with oligoasthenozoospermia, and it has positive clinical significance.

  18. Reviews of plasma physics

    CERN Document Server

    2008-01-01

    "Reviews of Plasma Physics Volume 24," edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence

  19. Reviews of plasma physics

    Energy Technology Data Exchange (ETDEWEB)

    Shafranov, Vitalii Dmitrievich (ed.); Bakunin, Oleg G. (comps.) [Rossijskij Nauchnyj Tsentr ' ' Kurchatovskij Inst.' ' , Moscow (Russian Federation). Nuclear Fusion Inst.; Rozhansky, V. [St. Petersburg State Polytechnical Univ. (Russian Federation)

    2008-07-01

    Reviews of Plasma Physics Volume 24, edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence (orig.)

  20. 多元组合ACS-TSP系统%A Multi-Metaheuristic Combined ACS-TSP System

    Institute of Scientific and Technical Information of China (English)

    陈芳

    2015-01-01

    文章提出了用多算法结合蚁族系统(ACS)求解旅行商问题(TSP)的方法,介绍了在ACS-TSP问题上的遗传算法,目的是为了寻找处理旅行商早期停滞现象的解空间.此外,还提出了一种新的最小生成树(MST)算法,结合最近邻(NN)来创建一个初始架构,以便又快又好地解决旅行商问题.%This paper presents a Multi-Metaheuristic combined Ant Colony System (ACS)-Travelling Salesman Problem (TSP) al-gorithm for solving the TSP. We introduce genetic algorithm in ACS-TSP to search solutions space for dealing with the early stagnation problem of the traveling salesman problem. Moreover, we present a new strategy of Minimum Spanning Tree(MST) coupled with Nearest Neighbor(NN) to construct a initial tour for improving TSP thus obtaining good solutions quickly. According to our simulation results, the new algorithm can provide a significant improvement for obtaining a global optimum solution or a near global optimum solution in large TSPs.

  1. A Study on Power Quality Improvement in PWM Controlled AC Voltage Controller

    Directory of Open Access Journals (Sweden)

    Ahmet ALTINTAŞ

    2009-04-01

    Full Text Available A lot of topologies of pulse-width modulated (PWM-AC controllers for single-phase and three-phase systems are proposed up to date. PWM-AC controllers have important advantages compared with the phase-controlled AC controllers using thyristors and triacs. The PWM-AC controller has sinusoidal current waveforms, smaller THD values, better power factor, faster dynamics, and smaller input/output filter. This article presents a novel control technique for application to PWM-AC controllers with ability of generating fewer harmonics. In the proposed control method, both the traditional AC voltage controllers and the PWM-AC controllers are combined; and smaller THD values are obtained. Thus, the harmonic pollution in the power system will be reduced; and consequently, the power quality will be increased. For this purpose, computer simulations are performed in order to investigate the proposed controller performance. The obtained results are compared with the conventional PWM-AC controller.

  2. Recent applications of AC electrokinetics in biomolecular analysis on microfluidic devices.

    Science.gov (United States)

    Sasaki, Naoki

    2012-01-01

    AC electrokinetics is a generic term that refers to an induced motion of particles and fluids under nonuniform AC electric fields. The AC electric fields are formed by application of AC voltages to microelectrodes, which can be easily integrated into microfluidic devices by standard microfabrication techniques. Moreover, the magnitude of the motion is large enough to control the mass transfer on the devices. These advantages are attractive for biomolecular analysis on the microfluidic devices, in which the characteristics of small space and microfluidics have been mainly employed. In this review, I describe recent applications of AC electrokinetics in biomolecular analysis on microfluidic devices. The applications include fluid pumping and mixing by AC electrokinetic flow, and manipulation of biomolecules such as DNA and proteins by various AC electrokinetic techniques. Future prospects for highly functional biomolecular analysis on microfluidic devices with the aid of AC electrokinetics are also discussed.

  3. Filterscope edge plasma diagnostic for the W7-X stellarator

    Science.gov (United States)

    Harris, Jeffrey; Unterberg, Ezekial; Lore, Jeremy; Stephey, Laurie; Schmitz, Oliver; Wurden, Glen; Biedermann, Christoph; Krychowiak, Maciej; Koenig, Ralf

    2015-11-01

    W7-X is a large (R = 5.5m, a = 0.5m, B 10 MW) superconducting stellarator at the Max-Planck Institut für Plasmaphysik in Greifswald, Germany, which will begin plasma operations in the last quarter of 2015. We describe here the first measurements with a 24-channel filterscope diagnostic [E. A. Unterberg et al., Rev. Sci. Instrum. 83, 10D722, (2012)] of edge plasma characteristics and spectral emission from impurities near the test limiters installed for initial plasma experiments. These measurements, together with high resolution IR thermography imaging of the limiter, will be used as inputs for edge transport modeling using the EMC3 code [J. D. Lore et al., Nucl. Fusion 52, 0540 (2012)]. This work is sponsored by DOE Contract No. DE-AC05- 00OR22725 with UT-Battelle.

  4. Prognostic Value of Plasma Intermedin Level in Patients With Non-ST-Segment Elevation Acute Coronary Syndrome.

    Science.gov (United States)

    Li, Pengyang; Shi, Lin; Han, Yalei; Zhao, Yuntao; Qi, Yongfen; Wang, Bin

    2016-04-01

    Intermedin (IMD), an autocrine/paracrine biologically active peptide, plays a critical role in maintaining vascular homeostasis. Recent research has shown that high plasma levels of IMD are associated with poor outcomes for patients with ST-segment elevation acute myocardial infarction. However, the prognostic utility of IMD levels in non-ST-segment elevation acute coronary syndrome (NSTE-ACS) has not yet been investigated. We hypothesized that the level of plasma IMD would have prognostic value in patients with NSTE-ACS. Plasma IMD was determined by radioimmunoassay in 132 NSTE-ACS patients on admission to hospital and 132 sex- and age-matched healthy-control subjects. Major adverse cardiovascular events (MACEs), including death, heart failure, hospitalization, and acute myocardial infarction, were noted during follow-up. In total, 23 patients suffered MACEs during the follow-up period (mean 227 ± 118 days, range 2-421 days). Median IMD levels were higher in NSTE-ACS patients than control [320.0 (250.9/384.6) vs. 227.2 (179.7/286.9) pg/mL, P variables and NT-proBNP showed that the risk of MACEs increased by a factor of 12.96 (95% CI, 3.26-49.42; P <0.001) with high IMD levels (at the cut-off value). IMD has potential as a prognostic biomarker for predicting MACEs in patients with NSTE-ACS.

  5. Dynamics of Ion Beam Charge Neutralization by Ferroelectric Plasma Sources

    Science.gov (United States)

    Stepanov, Anton D.; Gilson, Erik P.; Grisham, Larry R.; Kaganovich, Igor D.; Davidson, Ronald C.; Ji, Qing; Persaud, Arun; Seidl, Peter A.; Schenkel, Thomas

    2016-10-01

    Ferroelectric Plasma Sources (FEPSs) can generate plasma that provides effective space-charge neutralization of intense high-perveance ion beams. Here we present experimental results on charge neutralization of a high-perveance 38 keV Ar+ beam by a FEPS plasma. By comparing the measured beam radius with the envelope model for space-charge expansion, it is shown that a charge neutralization fraction of 98% is attainable. The transverse electrostatic potential of the ion beam is reduced from 15 V before neutralization to 0.3 V, implying that the energy of the neutralizing electrons is below 0.3 eV. Near-complete charge neutralization is established 5 μs after the driving pulse is applied to the FEPS, and can last for 35 μs. It is argued that the duration of neutralization is much longer than a reasonable lifetime of the plasma produced in the sub- μs surface discharge. Measurements of current flow in the driving circuit of the FEPS suggest that plasma can be generated for tens of μs after the high voltage pulse is applied. This is confirmed by fast photography of the plasma in the 1-meter long FEPS on NDCX-II, where effective charge neutralization of the beam was achieved with the optimized FEPS timing. This work was supported by the Office of Science of the US Department of Energy under contracts DE-AC0209CH11466 (PPPL) and DE-AC0205CH11231 (LBNL).

  6. Operation of a microwave plasma source for electron heating and antenna testing

    Science.gov (United States)

    Caughman, J. B. O.; Bigelow, T. S.; Diem, S. J.; Goulding, R. H.; Rasmussen, D. A.; Schaich, C. R.; White, T. L.

    2011-10-01

    One of the major challenges for magnetic fusion is the interaction of the plasma with materials. Linear plasma-material interaction test stands can benefit from additional electron heating of the high-density source plasma to increase the total plasma heat flux at the target to better simulate fusion reactor conditions (10-20 MW/m2). A microwave-based plasma experiment has begun at ORNL to study electron heating of over-dense plasmas and to provide a plasma environment for antenna testing. The plasma is generated by high-field launched whistler waves at 18 GHz to create a moderate-density plasma (ne ~1018/m3). Electron heating of the over-dense plasma is provided by either whistler waves or electron Bernstein waves at 6 GHz. In addition, a single strap mockup antenna, designed to operate at 40-50 MHz, is being constructed to study near-field plasma interactions. The antenna will be placed in the experiment's central vacuum chamber, which will act as an rf test facility. ORNL is managed by UT-Battelle, LLC, for the U.S. DOE under contract DE-AC-05-00OR22725.

  7. Hot plasma dielectric tensor

    NARCIS (Netherlands)

    Westerhof, E.

    1996-01-01

    The hot plasma dielectric tensor is discussed in its various approximations. Collisionless cyclotron resonant damping and ion/electron Bernstein waves are discussed to exemplify the significance of a kinetic description of plasma waves.

  8. Special issue: Plasma Conversion

    NARCIS (Netherlands)

    Nozaki, T.; Bogaerts, A.; Tu, X.; van de Sanden, M. C. M.

    2017-01-01

    With growing concern of energy and environmental issues, the combination of plasma and heterogeneous catalysts receives special attention in greenhouse gas conversion, nitrogen fixation and hydrocarbon chemistry. Plasma gas conversion driven by renewable electricity is particularly important for the

  9. High-performance modeling of plasma-based acceleration and laser-plasma interactions

    Science.gov (United States)

    Vay, Jean-Luc; Blaclard, Guillaume; Godfrey, Brendan; Kirchen, Manuel; Lee, Patrick; Lehe, Remi; Lobet, Mathieu; Vincenti, Henri

    2016-10-01

    Large-scale numerical simulations are essential to the design of plasma-based accelerators and laser-plasma interations for ultra-high intensity (UHI) physics. The electromagnetic Particle-In-Cell (PIC) approach is the method of choice for self-consistent simulations, as it is based on first principles, and captures all kinetic effects, and also scale favorably to many cores on supercomputers. The standard PIC algorithm relies on second-order finite-difference discretization of the Maxwell and Newton-Lorentz equations. We present here novel formulations, based on very high-order pseudo-spectral Maxwell solvers, which enable near-total elimination of the numerical Cherenkov instability and increased accuracy over the standard PIC method for standard laboratory frame and Lorentz boosted frame simulations. We also present the latest implementations in the PIC modules Warp-PICSAR and FBPIC on the Intel Xeon Phi and GPU architectures. Examples of applications will be given on the simulation of laser-plasma accelerators and high-harmonic generation with plasma mirrors. Work supported by US-DOE Contracts DE-AC02-05CH11231 and by the European Commission through the Marie Slowdoska-Curie fellowship PICSSAR Grant Number 624543. Used resources of NERSC.

  10. Software Development for ALMA in Chile: The ACS-UTFSM Group.

    Science.gov (United States)

    von Brand, H. H.

    ALMA Common Software (ACS) provides a common software framework for ALMA, the Atacama Large Millimeter Array in Chile. ACS is a collection of well-documented patterns for controlling systems and a set of components written to those patterns. In its core, ACS is a distributed, object-oriented system, written on top of CORBA. The ACS-UTFSM Group started as some students of informatics did summer jobs at the La Silla Observatory of ESO, where they became acquainted with ACS. Their interest led them to continue working on ACS on their own, and they eventually became official developers of the package. Now the group is being funded by project ALMA-CONICYT 31060008 ``Software Development for ALMA: Building Up Expertise to Meet ALMA Software Requirements within a Chilean University''. Several members of the original group are now working for ALMA, which fullfills one of the goals of the project. Some parts of ACS developed by the ACS-UTFSM Group include H3E (Hardware End-to-End Example), a Lego model of a telescope and its controlling software for training and demonstration purposes; and CDBChecker, a tool to verify the consistency of the configuration database for a ACS deployment. Currently we are working towards a general framework for telescope control using ACS, in order to simplify the deployment of new instruments; and repackaging ACS so it is easier to install and use. A master's thesis is exploring the real-time requirements of ACS.

  11. File list: His.PSC.50.H3ac.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.50.H3ac.AllCell mm9 Histone H3ac Pluripotent stem cell SRX882861,SRX882864,...SRX882865,SRX882862,SRX882860,SRX882863 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.50.H3ac.AllCell.bed ...

  12. Scaling of ac susceptibility and the nonlinear response function of high-temperature superconductors

    Institute of Scientific and Technical Information of China (English)

    CHEN; Kaixuan; NING; Zhenhua; XU; Hengyi; QI; Zhi; LU; Guo

    2005-01-01

    The amplitude-dependent ac susceptibility of high-temperature superconductors is shown to obey some empirical scaling relations. We try to analyze this behavior by extending a dc nonlinear response function of mixed state to the ac cases. The derived equations for critical current and ac susceptibility x(T) agree with the scaling relations of experimental data.

  13. Investigation and comparison of AC losses on stabilizer-free and copper stabilizer HTS tapes

    Science.gov (United States)

    Shen, Boyang; Li, Jing; Geng, Jianzhao; Fu, Lin; Zhang, Xiuchang; Li, Chao; Zhang, Heng; Dong, Qihuan; Ma, Jun; Coombs, T. A.

    2017-10-01

    This paper presents the measurement and simulation of Alternating Current (AC) losses on the Stabilizer-free and Copper Stabilizer High Temperature Superconducting (HTS) Tapes: SuperPower SF12100 and SCS12050. The AC loss measurement utilised electrical method to obtain overall losses with AC transport currents. The 2D H-formulation by COMSOL Multiphysics has been used to simulate the real geometry and multi-layer HTS tapes. Ferromagnetic AC losses of substrate have been assumed to be ignored as the substrates of SF12100 and SCS12050 are non-magnetic. Hysteresis AC losses in the superconducting layer, and eddy-current AC losses in copper stabilizer, silver overlayer and substrate were concerned in this investigation. The measured AC losses were compared to the AC losses from simulation, with 3 cases of different AC frequency 10, 100, and 1000 Hz. The eddy-current AC losses of copper stabilizer at frequency 1000 Hz were determined from both experiment and simulation. The estimation of AC losses with frequency at 10,000 Hz was also carried out using simulation method. Finally, the frequency dependence of AC losses from Stabilizer-free Tape and Copper Stabilizer Tape were compared and analysed.

  14. 21 CFR 880.5100 - AC-powered adjustable hospital bed.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered adjustable hospital bed. 880.5100... (CONTINUED) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Therapeutic Devices § 880.5100 AC-powered adjustable hospital bed. (a) Identification. An AC-powered...

  15. A Dual-Buck–Boost AC/DC Converter for DC Nanogrid With Three Terminal Outputs

    DEFF Research Database (Denmark)

    Wu, Weimin; Wang, Houqing; Liu, Yuan

    2017-01-01

    such as the low-voltage ac power system. There are three typical grounding configurations for a dc nanogrid: the united grounding, the unidirectional grounding, and the virtual isolated grounding. Each grounding configuration has its own specifications to ac/dc converters. In this paper, a dual-buck-boost ac...

  16. Examining the Effects of Introducing Online Access to ACS Journals at Primarily Undergraduate Institutions

    Science.gov (United States)

    Landolt, R. G.

    2007-01-01

    In collaboration with the Publications Division of the American Chemical Society (ACS), students and faculty at 24 primarily undergraduate institutions were provided online access to ACS primary research journals for a period of 18 months, and a group of eight schools were granted access to use the archives of ACS journals for a year. Resources…

  17. AC-13混合料矿料级配及特性试验研究%Research on AC-13 mixture mineral materials gradation and feature experiments

    Institute of Scientific and Technical Information of China (English)

    何亦伟

    2016-01-01

    The paper adopts the Marshall method and Superpave method,undertakes the mixture design for AC-13Ⅰand AC-13,compares and analyzes the optimal asphalt volume and compaction features of the two,and points out the designed asphalt volumes has the same optimal asphalt and aggregate ratio,and the latter is superior to the former one in the aspect of compaction.%应用马歇尔法和Superpave法对AC-13Ⅰ和AC-13进行了混合料设计,对比分析了两者的最佳沥青用量及压实特性,指出两者的设计沥青用量在最佳油石比时基本相同,AC-13的压实特性优于AC-13Ⅰ.

  18. Microwave Argon Plasma Torch

    Science.gov (United States)

    2013-07-01

    an electron-ion pair in the discharge. Fig. 2. EEDF is non - Maxwellian and changes along the plasma column The electron–neutral collision...plasma radius. Even at atmospheric pressure the EEDF is non - Maxwellian and it is changing along the plasma column. ...18 31st ICPIG, July 14-19, 2013, Granada, Spain EEDF usually strongly differs from Maxwellian and chages along the plasma column (this is

  19. 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.

  20. 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.