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Sample records for kapton butyl nylon

  1. Compatibility analysis of Nylon 6 and poly(ethylene-n-butyl acrylate-maleic anhydride) elastomer blends using isothermal crystallization kinetics

    Biber, Erkan, E-mail: ebiber@cankaya.edu.tr [Middle East Technical University, Polymer Science and Technology Department, Ankara (Turkey); Cankaya University, Industrial Engineering Department, Ankara (Turkey); Guenduez, Guengoer [Middle East Technical University, Polymer Science and Technology Department, Ankara (Turkey); Middle East Technical University, Chemical Engineering Department, Ankara (Turkey); Mavis, Bora [Hacettepe University, Mechanical Engineering Department, Ankara (Turkey); Colak, Uner [Hacettepe University, Nuclear Energy Engineering Department, Ankara (Turkey)

    2010-07-01

    Nylon 6 is a widely used engineering polymer, and has relatively poor impact strength. Ethylene, n-Butyl acrylate, maleic anhydride (E-nBA-MAH) terpolymer is blended with Nylon 6 to enhance its impact strength. Mixture should be compatible to be used in applications. The bare interaction energy between Nylon 6 and E-nBA-MAH terpolymer is calculated according to melting point depression approach using both Flory-Huggins (FH) Theory and Sanchez-Lacombe Equation of State (SL EOS). It demonstrates that blends are thermodynamically favorable to any arrangements. Yet, isothermal crystallization kinetics and WAXS crystallization peaks of blends reveal that mixtures of various compositions have different crystallization behaviors and require alternating crystallization energy due to crystalline structures of individual polymers. Also, SEM images support that after 5% addition of elastomeric terpolymer, interaction loosens due to strong crystalline structure of Nylon 6.

  2. Flexible spintronic devices on Kapton

    Bedoya-Pinto, Amilcar; Donolato, Marco; Gobbi, Marco

    2014-01-01

    Magnetic tunnel junctions and nano-sized domain-wall conduits have been fabricated on the flexible substrate Kapton. Despite the delicate nature of tunneling barriers and zig-zag shaped nanowires, the devices show an outstanding integrity and robustness upon mechanical bending. High values of ben...

  3. Positron implantation profile in kapton

    Plotkowski, K.; Panek, T.J.; Kansj, J.

    1988-01-01

    Measurements of positrons' implantation profile were made with geometry as in the majority of PAT experiments, making use of the difference in values of mean lifetimes of positrons in the absorber and in the detector. The function describing the absorption of positrons in the absorber taking into account measurement geometry was fitted to the experimental data. The correction to the exponential relation occurring in this function is the dominating factor for small thicknesses of the absorber. In this analysis various values of positrons' backscatter coefficients of the nickel and of the kapton were also taken into account

  4. Multidirectional Artificial Muscles from Nylon.

    Mirvakili, Seyed M; Hunter, Ian W

    2017-01-01

    Multidirectional artificial muscles are made from highly oriented nylon filaments. Thanks to the low thermal conductivity of nylon and its anisotropic thermal expansion, bending occurs when a nylon beam is differentially heated. This heat can be generated via a Joule heating mechanism or high power laser pulses. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Positron annihilation lifetime spectroscopy study of Kapton thin foils

    Kanda, G. S.; Ravelli, L.; Löwe, B.; Egger, W.; Keeble, D. J.

    2016-01-01

    Variable energy positron annihilation lifetime spectroscopy (VE-PALS) experiments on polyimide material Kapton are reported. Thin Kapton foils are widely used in a variety of mechanical, electronic applications. PALS provides a sensitive probe of vacancy-related defects in a wide range of materials, including open volume in polymers. Varying the positron implantation energy enables direct measurement of thin foils. Thin Kapton foils are also commonly used to enclose the positron source material in conventional PALS measurements performed with unmoderated radionuclide sources. The results of depth-profiled positron lifetime measurements on 7.6 μm and 25 μm Kapton foils are reported and determine a dominant 385(1) ps lifetime component. The absence of significant nanosecond lifetime component due to positronium formation is confirmed.

  6. Theoretical models of Kapton heating in solar array geometries

    Morton, Thomas L.

    1992-01-01

    In an effort to understand pyrolysis of Kapton in solar arrays, a computational heat transfer program was developed. This model allows for the different materials and widely divergent length scales of the problem. The present status of the calculation indicates that thin copper traces surrounded by Kapton and carrying large currents can show large temperature increases, but the other configurations seen on solar arrays have adequate heat sinks to prevent substantial heating of the Kapton. Electron currents from the ambient plasma can also contribute to heating of thin traces. Since Kapton is stable at temperatures as high as 600 C, this indicates that it should be suitable for solar array applications. There are indications that the adhesive sued in solar arrays may be a strong contributor to the pyrolysis problem seen in solar array vacuum chamber tests.

  7. Perhydropolysilazane derived silica coating protecting Kapton from atomic oxygen attack

    Hu Longfei [China Academy of Aerospace Aerodynamics, Beijing 100074 (China); Li Meishuan, E-mail: mshli@imr.ac.cn [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Xu Caihong; Luo Yongming [Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China)

    2011-11-30

    By using surface sol-gel method with perhydropolysilazane (PHPS) as a precursor, a silica coating was prepared on a Kapton substrate as an atomic oxygen (AO) protective coating. The AO exposure tests were conducted in a ground-based simulator. It is found that the erosion yield of Kapton decreases by about three orders of magnitude after the superficial application of the coating. After AO exposure, the surface of the coating is smooth and uniform, no surface shrinkage induced cracks or undercutting erosion are observed. This is because that during AO exposure the PHPS is oxidized directly to form SiO{sub 2} without through intermediate reaction processes, the surface shrinkage and cracking tendency are prohibited. Meanwhile, this PHPS derived silica coating also presents self-healing effect due to the oxidation of free Si. Compared with other kinds of silica or organic polymer coatings, this PHPS derived silica coating exhibits a superior AO erosion resistance.

  8. Perhydropolysilazane derived silica coating protecting Kapton from atomic oxygen attack

    Hu Longfei; Li Meishuan; Xu Caihong; Luo Yongming

    2011-01-01

    By using surface sol–gel method with perhydropolysilazane (PHPS) as a precursor, a silica coating was prepared on a Kapton substrate as an atomic oxygen (AO) protective coating. The AO exposure tests were conducted in a ground-based simulator. It is found that the erosion yield of Kapton decreases by about three orders of magnitude after the superficial application of the coating. After AO exposure, the surface of the coating is smooth and uniform, no surface shrinkage induced cracks or undercutting erosion are observed. This is because that during AO exposure the PHPS is oxidized directly to form SiO 2 without through intermediate reaction processes, the surface shrinkage and cracking tendency are prohibited. Meanwhile, this PHPS derived silica coating also presents self-healing effect due to the oxidation of free Si. Compared with other kinds of silica or organic polymer coatings, this PHPS derived silica coating exhibits a superior AO erosion resistance.

  9. Further studies on the filtration of liquids using Kapton nuclear track micro filters

    Guo, S.L.; Ganz, M.; Fuest, M.; Vater, P.; Brandt, R.

    1990-01-01

    The flow rate of some liquids (water, heptane, toluene, xylene, dodecane) through Kapton nuclear track filters has been measured. The results can be interpreted with a modified Poiseuille formula. The influence of the viscosity of the liquids on their throughput through Kapton nuclear track filters has been determined. The purification of liquids with Kapton filters has been investigated. It is possible to measure the density of solid particles in deionized water by using Kapton filters. Consequently, nuclear track filters can remove solid particles from high-purity liquids. The soaking effect of some common liquid chemicals on Kapton filters has also been studied, no such soaking could be observed in most of the cases. Finally, these Kapton nuclear track filters are compared with a filter device from Hamamatsu (Japan). (orig.) [de

  10. Knitmesh And Duplex-Nylon Type Coalescence Aids Use In Phase Disengagement

    Hamit Topuz

    2017-10-01

    Full Text Available This study shows how dispersions consisted of droplet sizes ranging from 100 microns and above of immiscible liquids in agitated vessels coalesced and settled back to their phases by employing commercially known as knit-mesh made from stainless steel and nylon. These components known as higher surface energy and lower surface energy contained coalesce aids respectively. In addition to compare coalesce aid made purely from commercially known as duplex-nylon also used. The experimental set up was 13 scale of a single stage mixer-settler unit of the already existing unit which was in use at BNFL Springfield Works. The liquid liquid system made from 20 tri-butyl-phosphate TBP technical grade of odorless kerosene forming the light organic phase or solvent phase and 5 M nitric acid forming the heavy aqueous phase. The solvent phase contained 70 gram of uranium per liter. Uranium contained phase was supplied by above mentioned company.

  11. Comparative Assessment of Copper-Coated Kapton: Analysis of Microclad from Several Manufacturing Lots

    Martz, Joseph Christopher [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Spearing, Dane Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Labouriau, Andrea [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Judge, Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kelly, Daniel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dirmyer, Matthew R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Milenski, Helen Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Patterson, Brian M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sandoval, Cynthia Wathen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Usov, Igor Olegovich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Beaux, Miles Frank II [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Henderson, Kevin C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Torres, Joseph Angelo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Edwards, Stephanie Lynn [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Vodnik, Douglas R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Keller, Jennie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mccabe, Rodney James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Livescu, Veronica [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cowan, Joseph Sarno [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Aragonez, Robert J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tokash, Justin Charles [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lawrence, Samantha Kay [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Leon Brito, Neliza [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-04-03

    Microclad is a composite material consisting of a thin copper coating applied on a single side over a Kapton substrate. Kapton is the commercial designator for polyimide supplied by DuPont. Microclad is a key material in detonator manufacture and function. Detonators which utilize Microclad function when a large current applied through a thin bridge etched into the copper produces a plasma, accelerating a Kapton flyer into an explosive (PETN) pellet. The geometry and properties of the Microclad are a critical element of this process.

  12. Ionizing radiation induced conductivity in Mylar (PET) and Kapton (Polyimide)

    Gregorio Filho, R.

    1986-01-01

    The extensive results of measurements of the prompt and delayed radiation-induced conductivity of samples of PET and Kapton are presented. Experimental parameters, such as the effective energy of the radiation, the exposure rate, the total dose, the value of the applied electric field, the nature of the electrodes, and the ambiental conditions were changed within wide limits. We also report measurement of thermally stimulated currents for non-irradiated and for irradiated samples which allowed us to investigate the trap-structure of the materials. Measurements of photo-Compton currents with different electrode materials and sample thicknesses gave information about the relation between the nature of the electrodes and the amplitudes of the currents. Based on the generalized rate theory of radiation-induced conduction we developed a theoretical model which includes the effect of the applied electric field on the carrier generation yield (geminate recombination, Onsager effect). Comparison of experimental and theoretical curves allowed us to determine the values of the main conduction parameters, such as carrier mobility, recombination coefficient, trap densities, for the materials under investigation. (Author) [pt

  13. Migration of divalent ions in nylon 6 films

    Reuvers, N.J.W.; Huinink, H.P.; Fischer, H.R.; Adan, O.C.G.

    2014-01-01

    The migration of ions through a nylon-6 film is studied by MRI. For this study the paramagnetic ions Mn2+ and Cu2+ are used as they act as a contrast agent and are detectable by MRI. The ingress of water and ions in nylon occurs at different rates. First, water is absorbed in the nylon. Second, the

  14. Nanoscratching of nylon 66-based ternary nanocomposites

    Dasari, Aravind; Yu Zhongzhen; Mai Yiuwing

    2007-01-01

    The nanoscratch behavior of nylon 66/SEBS-g-MA/clay ternary nanocomposites produced by different blending protocols with contrasting microstructures is studied by using atomic force and transmission electron microscopy. A standard diamond Berkovich indenter is used for scratching and a low load of 1 mN, along with a low sliding velocity of 1 μm s -1 , are employed for this purpose. It is shown that in order to resist penetration it is more important to have exfoliated clay in the continuous nylon matrix during nanoscratching than to have the clay in the dispersed soft rubber domains. The results obtained also explain the preferred usage of ternary nanocomposites compared to binary nanocomposites, particularly nylon 66/exfoliated clay nanocomposites. This research extends current basic knowledge and provides new insights on the nature of nanoscale processes that occur during nanoscratching of polymer nanocomposites. Critical questions are raised on the relationships between the penetration depth and material deformation and damage left behind the moving indenter

  15. Oxygen Plasma Modification of Poss-Coated Kapton(Registered TradeMark) HN Films

    Wohl, C. J.; Belcher, M. A.; Ghose, S.; Connell, J. W.

    2008-01-01

    The surface energy of a material depends on both surface composition and topographic features. In an effort to modify the surface topography of Kapton(Registered TradeMark) HN film, organic solutions of a polyhedral oligomeric silsesquioxane, octakis(dimethylsilyloxy)silsesquioxane (POSS), were spray-coated onto the Kapton(Registered TradeMark) HN surface. Prior to POSS application, the Kapton(Registered TradeMark) HN film was activated by exposure to radio frequency (RF)-generated oxygen plasma. After POSS deposition and solvent evaporation, the films were exposed to various durations of RF-generated oxygen plasma to create a topographically rich surface. The modified films were characterized using optical microscopy, attenuated total reflection infrared (ATR-IR) spectroscopy, and high-resolution scanning electron microscopy (HRSEM). The physical properties of the modified films will be presented.

  16. Kapton charging characteristics: Effects of material thickness and electron-energy distribution

    Williamson, W. S.; Dulgeroff, C. R.; Hymann, J.; Viswanathan, R.

    1985-01-01

    Charging characteristics of polyimide (Kapton) of varying thicknesses under irradiation by a very-low-curent-density electron beam, with the back surface of the sample grounded are reported. These charging characteristics are in good agreement with a simple analytical model which predicts that in thin samples at low current density, sample surface potential is limited by conduction leakage through the bulk material. The charging of Kapton in a low-current-density electron beam in which the beam energy was modulated to simulate Maxwellian and biMaxwellian distribution functions is measured.

  17. Absorption of water and lubricating oils into porous nylon

    Bertrand, P. A.

    1995-01-01

    Oil and water absorption from air into sintered porous nylon can be described by infiltration into the pores of the material. This process can be modeled by a diffusion-like mechanism. For water absorption, we find a formal diffusion coefficient of 1.5 x 10(exp -4)sq cm/min when the nylon is initially dry. The diffusion coefficient is 4 x 10(exp -6)sq cm/min when the nylon is oil-impregnated prior to air exposure. In a 52% RH atmosphere, dry nylon absorbs 3% w/w water, and oil-impregnated nylon absorbs 0.6% w/w water. For oil absorption there are three steps: (1) surface absorption and infiltration into (2) larger and (3) smaller pores. Surface absorption is too fast to be measured in these experiments. The diffusion coefficient for the second step is 6 x 10(exp -4)sq cm/min for SRG-60 oil into dry nylon and 4 x 10(exp -4)sq cm/min for air-equilibrated nylon. The diffusion coefficient for the third step is about 1 x 10(exp -6)sq cm/min for both cases. The total amount of oil absorbed is 31% w/w. The interaction between water and nylon is not as strong as that between water and cotton-phenolic: oil can replace water, and only a small amount of water can enter previously oil-impregnated nylon.

  18. A Compact Kapton-based Inkjet Printed Multiband Antenna for Flexible Wireless Devices

    Ahmed, Sana; Tahir, Farooq; Shamim, Atif; Cheema, Hammad M.

    2015-01-01

    Kapton polyimide-based flexible substrate with dimensions of 70 x 70 x 0.11 mm3. The antenna covers four wide frequency bands with measured impedance bandwidths of 54.4%, 14%, 23.5% and 17.2%, centered at 1.2, 2.0, 2.6 and 3.4 GHz, respectively, thus

  19. Environmental study of nylon flocking process.

    Burkhart, J; Piacitelli, C; Schwegler-Berry, D; Jones, W

    1999-05-14

    Environmental measurements for a variety of gas, particulate, and microbiological agents have been made in order to characterize exposures associated with the nylon flocking process. Of all agents measured, particulate is the predominant exposure. Levels of total particulate ranged from O.1 to 240 mg/m3 (x = 11.4 mg/m3). Average respirable particulate was 2.2 mg/m3, ranging from 0.5 to 39.9 mg/m3. Highest levels of particulates were found in the flocking room, and direct reading dust measurements indicate that the highest peak exposures are associated with "blowdown" (a cleaning procedure used between flocking runs). The nature of the airborne particles was investigated using polarized light and scanning electron microscopy. Air samples were found to contain flock particles (fibers nominally 10-15 microm in diameter by about 1000 microm in length) and a variety of respirable particles types, several of which were linked directly to the process. Of special interest were elongated respirable particles, which by microscopic analysis, complemented with melting-point determination, were found to be shreds of nylon.

  20. Classroom Illustrations of Acidic Air Pollution Using Nylon Fabric

    Campbell, Dean J.; Wright, Emily A.; Dayisi, Mardhia O.; Hoehn, Michael R.; Kennedy, Branden F.; Maxfield, Brian M.

    2011-01-01

    In 1970, deposition of fly ash from a coal burning power plant in downtown Peoria produced minor damage in the vicinity of its smokestack, including runs in ladies nylon stockings. In this article, we review the historical event and discuss the chemistry behind the depolymerization of the nylon, as well as laboratory experiments demonstrating how…

  1. Ductile transition in nylon-rubber blends: influence of water

    Gaymans, R.J.; Borggreve, R.J.M.; Spoelstra, A.B.

    1989-01-01

    On nylon 6 and nylon 6/EPDM blends the influence of water on the glass transition temperature, mechanical properties, and the ductile transition temperature was studied. Blends of 10% and 20% were prepared with a particle size of 0.3 µm and the tensile properties, flexural moduli, torsion moduli,

  2. X-ray transition yields of low-Z kaonic atoms produced in Kapton

    Bazzi, M. [INFN, Laboratori Nazionali di Frascati, C.P. 13, Via E. Fermi 40, I-00044 Frascati (Roma) (Italy); Beer, G. [Department of Physics and Astronomy, University of Victoria, P.O. Box 1700 STN CNC, Victoria, BC V8W 2Y2 (Canada); Berucci, C. [INFN, Laboratori Nazionali di Frascati, C.P. 13, Via E. Fermi 40, I-00044 Frascati (Roma) (Italy); Stefan-Meyer-Institut für subatomare Physik, Boltzmanngasse 3, 1090 Wien (Austria); Bombelli, L. [Politecnico di Milano, Dipartimento di Elettronica e Informazione, Piazza L. da Vinci 32, I-20133 Milano (Italy); Bragadireanu, A.M. [INFN, Laboratori Nazionali di Frascati, C.P. 13, Via E. Fermi 40, I-00044 Frascati (Roma) (Italy); IFIN-HH, Institutul National pentru Fizica si Inginerie Nucleara Horia Hulubei, Reactorului 30, Magurele (Romania); Cargnelli, M. [Stefan-Meyer-Institut für subatomare Physik, Boltzmanngasse 3, 1090 Wien (Austria); Curceanu, C.; D' Uffizi, A. [INFN, Laboratori Nazionali di Frascati, C.P. 13, Via E. Fermi 40, I-00044 Frascati (Roma) (Italy); Fiorini, C. [Politecnico di Milano, Dipartimento di Elettronica e Informazione, Piazza L. da Vinci 32, I-20133 Milano (Italy); Ghio, F. [INFN Sezione di Roma I and Instituto Superiore di Sanita, I-00161 Roma (Italy); Guaraldo, C. [INFN, Laboratori Nazionali di Frascati, C.P. 13, Via E. Fermi 40, I-00044 Frascati (Roma) (Italy); Hayano, R.S. [University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo (Japan); Iliescu, M. [INFN, Laboratori Nazionali di Frascati, C.P. 13, Via E. Fermi 40, I-00044 Frascati (Roma) (Italy); Ishiwatari, T., E-mail: tomoichi.ishiwatari@assoc.oeaw.ac.at [Stefan-Meyer-Institut für subatomare Physik, Boltzmanngasse 3, 1090 Wien (Austria); Iwasaki, M. [RIKEN, Institute of Physical and Chemical Research, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); and others

    2013-10-23

    The X-ray transition yields of kaonic atoms produced in Kapton polyimide (C{sub 22}H{sub 10}N{sub 2}O{sub 5}) were measured for the first time in the SIDDHARTA experiment. X-ray yields of the kaonic atoms with low atomic numbers (Z=6,7, and 8) and transitions with high principal quantum numbers (n=5–8) were determined. The relative yields of the successive transitions in the same atoms and the yield ratios of carbon-to-nitrogen (C:N) and carbon-to-oxygen (C:O) for the same transitions were also determined. These X-ray yields provide important information for understanding the capture ratios and cascade mechanisms of kaonic atoms produced in a compound material, such as Kapton.

  3. Titania seed layers for PZT thin film growth on copper-coated Kapton films

    Suchaneck, G.; Volkonskiy, O.; Hubička, Zdeněk; Dejneka, Alexandr; Jastrabík, Lubomír; Adolphi, B.; Bertram, M.; Gerlach, G.

    2009-01-01

    Roč. 108, č. 1 (2009), s. 57-66 ISSN 1058-4587 R&D Projects: GA ČR GC202/09/J017; GA AV ČR KJB100100703 Institutional research plan: CEZ:AV0Z10100522 Keywords : copper coated Kapton * seed layer * seed layer * plasma deposition * XPS Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.329, year: 2009

  4. The Effect of Salt Splash on Nylon 6,6

    Steward, Scott D

    1999-01-01

    Abstract: One of the most common environmental exposures that nylon undergoes, when used for automotive applications, is that of salt splash, which commonly occurs during winter driving. This study looks at the effect of various salts (NaCl, KCl, CaCl2) on the thermal and mechanical properties of nylon when exposed to one and four molar aqueous salt solutions. It was found that the diffusion of salt solutions into nylon 6,6 occurred in a pseudo-Fickian manner. Also, it was found that the p...

  5. Equilibrium thermodynamics of the ternary membrane-forming system nylon, formic acid and water

    Bulte, A.M.W.; Bulte, A.M.W.; Naafs, E.M.; van Eeten, F.; Mulder, M.H.V.; Smolders, C.A.; Smolders, C.A.; Strathmann, H.

    1996-01-01

    The binary Flory-Huggins interaction parameters for the ternary membrane-forming system nylon, formic acid and water have been obtained from literature data, swelling values and melting point depression. Nylon 4,6 nylon 6 and a copolymer of nylon 4,6 and 6 were examined. The isothermal

  6. Mechanical Properties of Nylon Harp Strings

    Lynch-Aird, Nicolas; Woodhouse, Jim

    2017-01-01

    Monofilament nylon strings with a range of diameters, commercially marketed as harp strings, have been tested to establish their long-term mechanical properties. Once a string had settled into a desired stress state, the Young’s modulus was measured by a variety of methods that probe different time-scales. The modulus was found to be a strong function of testing frequency and also a strong function of stress. Strings were also subjected to cyclical variations of temperature, allowing various thermal properties to be measured: the coefficient of linear thermal expansion and the thermal sensitivities of tuning, Young’s modulus and density. The results revealed that the particular strings tested are divided into two groups with very different properties: stress-strain behaviour differing by a factor of two and some parametric sensitivities even having the opposite sign. Within each group, correlation studies allowed simple functional fits to be found to the key properties, which have the potential to be used in automated tuning systems for harp strings. PMID:28772858

  7. Mechanical Properties of Nylon Harp Strings

    Nicolas Lynch-Aird

    2017-05-01

    Full Text Available Monofilament nylon strings with a range of diameters, commercially marketed as harp strings, have been tested to establish their long-term mechanical properties. Once a string had settled into a desired stress state, the Young’s modulus was measured by a variety of methods that probe different time-scales. The modulus was found to be a strong function of testing frequency and also a strong function of stress. Strings were also subjected to cyclical variations of temperature, allowing various thermal properties to be measured: the coefficient of linear thermal expansion and the thermal sensitivities of tuning, Young’s modulus and density. The results revealed that the particular strings tested are divided into two groups with very different properties: stress-strain behaviour differing by a factor of two and some parametric sensitivities even having the opposite sign. Within each group, correlation studies allowed simple functional fits to be found to the key properties, which have the potential to be used in automated tuning systems for harp strings.

  8. Superhydrophobic nanostructured Kapton® surfaces fabricated through Ar + O2 plasma treatment: Effects of different environments on wetting behaviour

    Barshilia, Harish C.; Ananth, A.; Gupta, Nitant; Anandan, C.

    2013-03-01

    Kapton® [poly (4,4'-oxy diphenylene pyromellitimide)] polyimides have widespread usage in semiconductor devices, solar arrays, protective coatings and space applications, due to their excellent chemical and physical properties. In addition to their inherent properties, imparting superhydrophobicity on these surfaces will be an added advantage. Present work describes the usage of Ar + O2 plasma treatment for the preparation of superhydrophobic Kapton® surfaces. Immediately after the plasma treatment, the surfaces showed superhydrophilicity as a result of high energy dangling bonds and polar group concentration. But the samples kept in low vacuum for 48 h exhibited superhydrophobicity with high water contact angles (>150°). It is found that the post plasma treatment process, called ageing, especially in low vacuum plays an important role in delivering superhydrophobic property to Kapton®. Field emission scanning electron microscopy and atomic force microscopy were used to probe the physical changes in the surface of the Kapton®. The surfaces showed formation of nano-feathers and nano-tussock microstructures with variation in surface roughness against plasma treatment time. A thorough chemical investigation was performed using Fourier transform infrared spectroscopy and micro-Raman spectroscopy, which revealed changes in the surface of the Ar + O2 plasma treated Kapton®. Surface chemical species of Kapton® were confirmed again by X-ray photoelectron spectroscopy spectra for untreated surfaces whereas Ar + O2 plasma treated samples showed the de-bonding and re-organization of structural elements. Creation of surface roughness plays a dominant role in the contribution of superhydrophobicity to Kapton® apart from the surface modifications due to Ar + O2 plasma treatment and ageing in low vacuum.

  9. Effects and mechanism on Kapton film under ozone exposure in a ground near space simulator

    Wei, Qiang; Yang, Guimin; Liu, Gang; Jiang, Haifu; Zhang, Tingting

    2018-05-01

    The effect on aircraft materials in the near space environment is a key part of air-and-space integration research. Ozone and aerodynamic fluids are important organizational factors in the near space environment and both have significant influences on the performance of aircraft materials. In the present paper a simulated ozone environment was used to test polyimide material that was rotated at the approximate velocity of 150-250 m/s to form an aerodynamic fluid field. The goal was to evaluate the performance evolution of materials under a comprehensive environment of ozone molecular corrosion and aerodynamic fluids. The research results show that corrosion and sputtering by ozone molecules results in Kapton films exhibiting a rugged "carpet-like" morphology exhibits an increase in surface roughness. The morphology after ozone exposure led to higher surface roughness and an increase in surface optical diffuse reflection, which is expressed by the lower optical transmittance and the gradual transition from light orange to brown. The mass loss test, XPS, and FTIR analysis show that the molecular chains on the surface of the Kapton film are destroyed resulting in Csbnd C bond breaking to form small volatile molecules such as CO2 or CO, which are responsible for a linear increase in mass loss per unit area. The Csbnd N and Csbnd O structures exhibit weakening tendency under ozone exposure. The present paper explores the evaluation method for Kapton's adaptability under the ozone exposure test in the near space environment, and elucidates the corrosion mechanism and damage mode of the polyimide material under the combined action of ozone corrosion and the aerodynamic fluid. This work provides a methodology for studying materials in the near-space environment.

  10. Photoinduced currents in pristine and ion irradiated kapton-H polyimide

    Sharma, Anu; Sridharbabu, Y.; Quamara, J. K.

    2014-10-01

    The photoinduced currents in pristine and ion irradiated kapton-H polyimide have been investigated for different applied electric fields at 200°C. Particularly the effect of illumination intensity on the maximum current obtained as a result of photoinduced polarization has been studied. Samples were irradiated by using PELLETRON facility, IUAC, New Delhi. The photo-carrier charge generation depends directly on intensity of illumination. The samples irradiated at higher fluence show a decrease in the peak current with intensity of illumination. The secondary radiation induced crystallinity (SRIC) is responsible for the increase in maximum photoinduced currents generated with intensity of illumination.

  11. Photoinduced currents in pristine and ion irradiated kapton-H polyimide

    Sharma, Anu, E-mail: sharmaanu81@gmail.com; Sridharbabu, Y., E-mail: sharmaanu81@gmail.com; Quamara, J. K., E-mail: sharmaanu81@gmail.com [Physics Department, SGTB Khalsa college, Delhi University, Delhi (India); Department of Physics, National Institute of Technology, Kurukshetra-136119 (India); Echelon Group of Institutions, Faridabad (India)

    2014-10-15

    The photoinduced currents in pristine and ion irradiated kapton-H polyimide have been investigated for different applied electric fields at 200°C. Particularly the effect of illumination intensity on the maximum current obtained as a result of photoinduced polarization has been studied. Samples were irradiated by using PELLETRON facility, IUAC, New Delhi. The photo-carrier charge generation depends directly on intensity of illumination. The samples irradiated at higher fluence show a decrease in the peak current with intensity of illumination. The secondary radiation induced crystallinity (SRIC) is responsible for the increase in maximum photoinduced currents generated with intensity of illumination.

  12. Studies on electrospun nylon-6/chitosan complex nanofiber interactions

    Zhang Haitao; Li Shubai; Branford White, Christopher J.; Ning Xin; Nie Huali; Zhu Limin

    2009-01-01

    Composite membranes of nylon-6/chitosan nanofibers with different weight ratio of nylon-6 to chitosan were fabricated successfully using electrospinning. Morphologies of the nanofibers were investigated by scanning electron microscopy (SEM) and the intermolecular interactions of the nylon-6/chitosan complex were evaluated by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) as well as mechanical testing. We found that morphology and diameter of the nanofibers were influenced by the concentration of the solution and weight ratio of the blending component materials. Furthermore FT-IR analyses on interactions between components demonstrated an IR band frequency shift that appeared to be dependent on the amount of chitosan in the complex. Observations from XRD and DSC suggested that a new fraction of γ phase crystals appeared and increased with the increasing content of chitosan in blends, this indicated that intermolecular interactions occurred between nylon-6 and chitosan. Results from performance data in mechanical showed that intermolecular interactions varied with varying chitosan content in the fibers. It was concluded that a new composite product was created and the stability of this system was attributed to strong new interactions such as hydrogen bond formation between the nylon-6 polymers and chitosan structures.

  13. Chitin butyrate coated electrospun nylon-6 fibers for biomedical applications

    Pant, Hem Raj; Kim, Han Joo; Bhatt, Lok Ranjan; Joshi, Mahesh Kumar; Kim, Eun Kyo; Kim, Jeong In; Abdal-hay, Abdalla; Hui, K. S.; Kim, Cheol Sang

    2013-11-01

    In this study, we describe the preparation and characterizations of chitin butyrate (CB) coated nylon-6 nanofibers using single-spinneret electrospinning of blends solution. The physicochemical properties of nylon-6 composite fibers with different proportions of CB to nylon-6 were determined using FE-SEM, TEM, FT-IR spectroscopy, and water contact angle measurement. FE-SEM and TEM images revealed that the nylon-6 and CB were immiscible in the as-spun nanofibers, and phase separated nanofiber morphology becomes more pronounced with increasing amounts of CB. The bone formation ability of composite fibers was evaluated by incubating in biomimetic simulated body fluid. In order to assay the cytocompatibility and cell behavior on the composite scaffolds, osteoblast cells were seeded on the matrix. Results suggest that the deposition of CB layer on the surface of nylon-6 could increase its cell compatibility and bone formation ability. Therefore, as-synthesized nanocomposite fibrous mat has great potentiality in hard tissue engineering.

  14. Esterification of fatty acids using nylon-immobilized lipase in n-hexane: kinetic parameters and chain-length effects.

    Zaidi, A; Gainer, J L; Carta, G; Mrani, A; Kadiri, T; Belarbi, Y; Mir, A

    2002-02-28

    The esterification of long-chain fatty acids in n-hexane catalyzed by nylon-immobilized lipase from Candida rugosa has been investigated. Butyl oleate (22 carbon atoms), oleyl butyrate (22 carbon atoms) and oleyl oleate (36 carbon atoms) were produced at maximum reaction rates of approximately equal to 60 mmol h(-1) g(-1) immobilized enzyme when the substrates were present in equimolar proportions at an initial concentration of 0.6 mol l(-1). The observed kinetic behavior of all the esterification reactions is found to follow a ping-pong bi-bi mechanism with competitive inhibition by both substrates. The effect of the chain-length of the fatty acids and the alcohols could be correlated to some mechanistic models, in accordance with the calculated kinetic parameters.

  15. Measurement of the elastic modulus of Kapton perpendicular to the plane of the film at room and cryogenic temperatures

    Davidson, M.; Bastian, S.; Markley, F.

    1992-04-01

    Understanding the short term elastic properties, (i.e. the instantaneous modulus) of Kapton is essential in determining the loss of prestress during storage and operation of SSC dipole magnets. The magnet prestress contributes directly to the coil response to the Lorentz forces during ramping. The instantaneous modulus is important in extrapolating short term stress relaxation data to longer times. Most theoretical fits assume a time independent component and a time dependent component. The former may be represented by the Kapton modulus near zero K where all relaxation processes have been ''frozen'' out. Modulus measurements at 77K and 4.2K may point to a correct value for the near zero K modulus. Three companion papers presented at this conference will be: ''Stress Relaxation in SSC 50 mm Dipole Coils'' ''Temperature Dependence of the Viscoelastic Properties of SSC Coil Insulation (Kapton)'' ''Theoretical Methods for Creep and Stress Relaxation Studies of SSC Coil.''

  16. Testing of SRS and RFETS Nylon Bag Material

    Laurinat, J.E.

    1998-01-01

    This report compares the effects of radiation and heating on nylon bagout materials used at the Savannah River Site (SRS) and the Rocky Flats Environmental Technology Site (RFETS). Recently, to simplify the processing of sand, slag, and crucible (SS and C), FB-Line has replaced the low-density polyethylene (LDPE) and polyvinyl chloride (PVC) bags normally used to package cans of plutonium-bearing material with nylon bags. LDPE and PVC are not soluble in the nitric acid dissolver solution used in F-Canyon, so cans bagged using these materials had to be repackaged before they were added to the dissolver. Because nylon dissolves in nitric acid, cans bagged in nylon can be charged to the F-Canyon dissolvers without repackaging, thereby reducing handling requirements and personnel exposure. As part of a program to process RFETS SS and C at SRS, RFETS has also begun to use a nylon bagout material. The RFETS bag materials is made from a copolymer of nylon 6 and nylon 6.9, while the SRS material is made from a nylon 6 monomer. In addition, the SRS nylon has an anti-static agent added. The RFETS nylon is slightly softer than the SRS nylon, but does not appear to be as resistant to flex cracks initiated by contact with sharp corners of the inner can containing the SS and C.2 FB-Line Operations has asked for measurement of the effects of radiation and heating on these materials. Specifically, they have requested a comparison of the material properties of the plastics before and after irradiation, a measurement of the amount of outgassing when the plastics are heated, and a calculation of the amount of radiolytic gas generation. Testing was performed on samples taken from material that is currently used in FB-Line (color coded orange) and at RFETS. The requested tests are the same tests previously performed on the original and replacement nylon and LDPE bag materials.3,4,5. To evaluate the effect of irradiation on material properties, tensile stresses and elongations to break

  17. Butyl Rubber: Compound Development and Characterization

    Sloan, James

    2000-01-01

    ...), to develop the standard butyl rubber compound. The strategy of this work was to compound- and compression-mold high-quality, uniform butyl rubber experimental sheets and to evaluate their cure properties, mechanical properties...

  18. Adsorption Properties of Lac Dyes on Wool, Silk, and Nylon

    Bo Wei

    2013-01-01

    Full Text Available There has been growing interest in the dyeing of textiles with natural dyes. The research about the adsorption properties of natural dyes can help to understand their adsorption mechanism and to control their dyeing process. This study is concerned with the kinetics and isotherms of adsorption of lac dyes on wool, silk, and nylon fibers. It was found that the adsorption kinetics of lac dyes on the three fibers followed the pseudosecond-order kinetic model, and the adsorption rate of lac dyes was the fastest for silk and the slowest for wool. The activation energies for the adsorption process on wool, silk, and nylon were found to be 107.15, 87.85, and 45.31 kJ/mol, respectively. The adsorption of lac dyes on the three fibers followed the Langmuir mechanism, indicating that the electrostatic interactions between lac dyes and those fibers occurred. The saturation values for lac adsorption on the three fibers decreased in the order of wool > silk > nylon; the Langmuir affinity constant of lac adsorption on nylon was much higher than those on wool and silk.

  19. Morphology and melt rheology of nylon 11/clay nanocomposites

    He, Xiaofeng; Yang, Jun; Zhu, Lianchao; Wang, Biao; Sun, Guangping; Lv, Pengfei; Phang, In Yee; Liu, Tianxi

    2006-01-01

    Nylon 11 (PA11)/clay nanocomposites have been prepared by melt-blending, followed by melt-extrusion through a capillary. Transmission electron microscopy shows that the exfoliated clay morphology is dominant for low nanofiller content, while the intercalated one is prevailing for high filler

  20. The Dependence of Atomic Oxygen Undercutting of Protected Polyimide Kapton(tm) H upon Defect Size

    Snyder, Aaron; deGroh, Kim K.

    2001-01-01

    Understanding the behavior of polymeric materials when exposed to the low-Earth-orbit (LEO) environment is important in predicting performance characteristics such as in-space durability. Atomic oxygen (AO) present in LEO is known to be the principal agent in causing undercutting erosion of SiO(x) protected polyimide Kapton(R) H film, which serves as a mechanically stable blanket material in solar arrays. The rate of undercutting is dependent on the rate of arrival, directionality and energy of the AO with respect to the film surface. The erosion rate also depends on the distribution of the size of defects existing in the protective coating. This paper presents results of experimental ground testing using low energy, isotropic AO flux together with numerical modeling to determine the dependence of undercutting erosion upon defect size.

  1. Optical and electrical properties of ion beam textured Kapton and Teflon

    Mirtich, M. J.; Sovey, J. S.

    1977-01-01

    An electron bombardment argon ion source was used to ion etch polyimide (Kapton) and fluorinated ethylene, FEP (Teflon). Samples of polyimide and FEP were exposed to (0.5-1.0) keV Ar ions at ion current densities of (1.0-1/8) mA/sq cm for various exposure times. Changes in the optical and electrical properties of the samples were used to characterize the exposure. Spectral reflectance and transmittance measurements were made between 0.33 and 2.16 micron m using an integrating sphere after each exposure. From these measurements, values of solar absorptance were obtained. Total emittance measurements were also recorded for some samples. Surface resistivity was used to determine changes in the electrical conductivity of the etched samples. A scanning electron microscope recorded surface structure after exposure. Spectral optical data, resistivity measurements, calculated absorptance and emittance measurements are presented along with photomicrographs of the surface structure for the various exposures to Ar ions.

  2. Condutividade induzida por radiação ionizante no Mylar (PET) e Kapton (polimiidia).

    Rinaldo Gregório Filho

    1986-01-01

    Este trabalho apresenta uma extensiva série de resultados experimentais da condutividade induzida por radiação X contínua, durante e após a irradiação, em amostras de PET e Kapton. As medidas foram realizadas variando-se uma série de parâmetros, tais como: o campo elétrico aplicado, a taxa de exposição, a espessura da amostra, o tipo de eletrodo, a energia da radiação e as condições ambientes. Foram feitas ainda medidas da corrente termo-estimulada em amostras irradiadas e não irradiadas, que...

  3. First tests of thick GEMs with electrodes made of a resistive kapton

    Oliveira, R.; Peskov, V.; Pietropaolo, F.; Picchi, P.

    2007-01-01

    We have developed a new design of a GEM-like detector with electrodes made of a resistive kapton. This detector can operate at gains close to 10 5 even in pure noble gases (Ar and Ne) and if transited to discharges at higher gains, due to the high resistivity of electrodes, they do not damage either the detector or the front-end electronics. Gains ∼10 6 can be achieved in a cascaded mode of operation. The detector can operate without gain degradation at counting rates of at least up to 10 4 Hz/cm 2 and it could thus be very useful in many applications requiring safe high-gain operation, for example, in RICH, TPCs, and calorimetry

  4. Nylon-6/rubber blends: 6. Notched tensile impact testing of nylon-6(ethylene-propylene rubber) blends

    Dijkstra, Krijn; Dijkstra, K.; ter Laak, J.A.; ter Laak, J.; Gaymans, R.J.

    1994-01-01

    The deformation and fracture behaviour of nylon-6/EPR (ethylene-propylene rubber) blends is studied as a function of strain rate and rubber content. Therefore, tensile experiments are conducted on notched specimens over a broad range of draw speeds (including strain rates as encountered in normal

  5. Nylon-sputtered nanoparticles: fabrication and basic properties

    Polonskyi, O.; Kylián, O.; Solař, P.; Artemenko, A.; Kousal, J.; Slavínská, D.; Choukourov, A.; Biederman, H.

    2012-12-01

    Nylon-sputtered nanoparticles were prepared using a simple gas aggregation cluster source based on a planar magnetron (Haberland type) and equipped with a nylon target. Plasma polymer particles originated in an aggregation chamber and travelled to a main (deposition) chamber with a gas flow through an orifice. The deposited nanoparticles were observed to have a cauliflower-like structure. The nanoparticles were found to be nitrogen-rich with N/C ratio close to 0.5. An increase in rf power from 60 to 100 W resulted in a decrease in mean particle size from 210 to 168 nm whereas an increase in their residence time in the cluster source from 0.7 to 4.6 s resulted in an increase in the size from 73 to 231 nm.

  6. Rheological characterization of nanocomposites Nylon 6/bentonite clay

    Silva, T.R.G.; Fernandes, P.C.; Oliveira, S.V.; Araujo, E.M.; Melo, T.J.A.

    2010-01-01

    Polymer nanocomposites are a class of materials that have been widely used in various applications. Among them, has been emphasizing the preparation of polymer films with barrier properties for applications in polymer membranes. In this work, nanocomposites of nylon 6/bentonite clay were obtained from a Homogenizer, in the ratios of 1, 3 and 5 wt% clay. The Brasgel PA bentonite clay was treated organically with Praepagen HY salt, to make it organophilic. By X-ray diffraction (XRD), it was showed that the efficiency of the incorporation of salt in the clay. The rheological curves showed that for the AST clay the torque did not change when compared with the pure nylon 6, while for the clay ACT, the torque increased gradually with the percentage of clay. (author)

  7. Rapid transfer of DNA from agarose gels to nylon membranes.

    Reed, K C; Mann, D A

    1985-01-01

    The unique properties of nylon membranes allow for dramatic improvement in the capillary transfer of DNA restriction fragments from agarose gels (Southern blotting). By using 0.4 M NaOH as the transfer solvent following a short pre-treatment of the gel in acid, DNA is depurinated during transfer. Fragments of all sizes are eluted and retained quantitatively by the membrane; furthermore, the alkaline solvent induces covalent fixation of DNA to the membrane. The saving in time and materials aff...

  8. Nylon friction dermatitis: A distinct subset of macular amyloidosis

    Somani V

    1995-01-01

    Full Text Available 43 patients were taken up for the study, all of whom were asymptomatic and presented with bluish black pigmentation. 23 patients presented with pigmentation which was proximal and distal to the bony prominences, all of whom gave a history of using nylon scrubbers during bathing. 20 patients gave no history of friction and the pigmentation was present on the extensor forearms, shins and upper back. Histopathological examination confirmed amyloid deposits.

  9. Development of Nylon Based FDM Filament for Rapid Tooling Application

    Singh, R.; Singh, S.

    2014-04-01

    There has been critical need for development of cost effective nylon based wire to be used as feed stock filament for fused deposition modelling (FDM) machine. But hitherto, very less work has been reported for development of alternate solution of acrylonitrile butadiene styrene (ABS) based wire which is presently used in most of FDM machines. The present research work is focused on development of nylon based wire as an alternative of ABS wire (which is to be used as feedstock filament on FDM) without changing any hardware or software of machine. For the present study aluminium oxide (Al2O3) as additive in different proportion has been used with nylon fibre. Single screw extruder was used for wire preparation and wire thus produced was tested on FDM. Mechanical properties i.e. tensile strength and percentage elongation of finally developed wire have been optimized by Taguchi L9 technique. The work represented major development in reducing cost and time in rapid tooling applications.

  10. Determinations of phase transitions in nylon 6-12, nylon-6, polyvinyl chloride and polyethylene terephthalate by positron annihilation spectroscopy

    Camacho Reyes, M.J.

    1993-01-01

    Positron annihilation lifetime spectroscopy (PALS) was used to investigate the phase transitions, mainly the glass transition, of poly(vinyl chloride) (PVC), Nylon-6,12, Nylon-6, poly(ethylene terephthalate) during the thermal treatment of these polymers. The longest lived component lifetime and intensity, indicative of ortho-Positronium pick-off exhibit thermal dependencies that can be attributed to the anticipated free volume changes associated with structural transitions. Positron lifetime measurements were performed using an E G and G Ortec standard fast-fast coincidence system. Three spectra were collected at each temperature, each consisting of a peak height of approximately 25000 counts. The resulting spectra were consistently modeled with a three component fit using the computer program PATFIT. For nylon-6,12, nylon-6, PVC systems three transitions were obtained in both tau-3 and I-3 as a function of temperature. Changes in the slope of the curves appear for both parameters, these could be attributed to T g1 , T g2 and T c , respectively. In the case of PET analysis two transitions were obtained as is shown by the variations of tau-3 as a function of the heating temperature. These transitions can be attributed to T g1 and T g2 . Similar changes can be observed for I-3 in relation with temperature. Glass transition behavior was evident in the lifetime behavior of polymers. Increases in slope of the lifetime temperature plots were interpreted free-volume cavity expansion as temperature is increased. The intensity responses in the vicinity of the upper glass transition were consistent with the association of this transition with the reduction of crystalline constraint of segmental mobility in the amorphous phase. (Author)

  11. Reflectance measurements of PTFE, Kapton, and PEEK for xenon scintillation light for the LZ detector.

    Arthurs, M.; Batista, E.; Haefner, J.; Lorenzon, W.; Morton, D.; Neff, A.; Okunawo, M.; Pushkin, K.; Sander, A.; Stephenson, S.; Wang, Y.; LZ Collaboration

    2017-01-01

    LZ (LUX-Zeplin) is an international collaboration that will look for dark matter candidates, WIMPs (Weakly Interacting Massive Particles), through direct detection by dual-phase time projection chamber (TPC) using liquid xenon. The LZ detector will be located nearly a mile underground at SURF, South Dakota, shielded from cosmic background radiation. Seven tons active mass of liquid xenon will be used for detecting the weak interaction of WIMPs with ordinary matter. Over three years of operation it is expected to reach the ultimate sensitivity of 2x10-48 cm2 for a WIMP mass of 50 GeV. As for many other rare event searches, high light collection efficiency is essential for LZ detector. Moreover, in order to achieve greater active volume for detection as well as reduce potential backgrounds, thinner detector walls without significant loss in reflectance are desired. Reflectance measurements of polytetrafluoroethylene (PTFE), Kapton, and PEEK for xenon scintillation light (178 nm), conducted at the University of Michigan using the Michigan Xenon Detector (MiX) will be presented. The University of Michigan, LZ Collaboration, The US Department of Energy.

  12. A Compact Kapton-based Inkjet Printed Multiband Antenna for Flexible Wireless Devices

    Ahmed, Sana

    2015-04-20

    A low cost inkjet printed multiband antenna envisioned for integration into flexible and conformal mobile devices is presented. The antenna structure contains a novel triangular iterative design with coplanar waveguide (CPW) feed, printed on a Kapton polyimide-based flexible substrate with dimensions of 70 x 70 x 0.11 mm3. The antenna covers four wide frequency bands with measured impedance bandwidths of 54.4%, 14%, 23.5% and 17.2%, centered at 1.2, 2.0, 2.6 and 3.4 GHz, respectively, thus, enabling it to cover GSM 900, GPS, UMTS, WLAN, ISM, Bluetooth, LTE 2300/ 2500 and WiMAX standards. The antenna has omnidirectional radiation pattern with a maximum gain of 2.1 dBi. To characterize the flexibility of the antenna, the fabricated prototype is tested in convex and concave bent configurations for radii of 78mm and 59mm. The overall performance remains unaffected, except a minor shift of 20 MHz and 60 MHz in S11, for concave bending at both radii. The compact, lightweight and conformal design as well as multiband performance in bent configurations, proves the suitability of the antenna for future electronic devices.

  13. A bio-enabled maximally mild layer-by-layer Kapton surface modification approach for the fabrication of all-inkjet-printed flexible electronic devices

    Fang, Yunnan; Hester, Jimmy G. D.; Su, Wenjing; Chow, Justin H.; Sitaraman, Suresh K.; Tentzeris, Manos M.

    2016-12-01

    A bio-enabled, environmentally-friendly, and maximally mild layer-by-layer approach has been developed to surface modify inherently hydrophobic Kapton HN substrates to allow for great printability of both water- and organic solvent-based inks thus facilitating the full-inkjet-printing of flexible electronic devices. Different from the traditional Kapton surface modification approaches which are structure-compromising and use harsh conditions to target, and oxidize and/or remove part of, the surface polyimide of Kapton, the present Kapton surface modification approach targeted the surface electric charges borne by its additive particles, and was not only the first to utilize environmentally-friendly clinical biomolecules to build up a thin film of protamine-heparin complex on Kapton, but also the first to be conducted under minimally destructive and maximally mild conditions. Besides, for electrically charged ink particles, the present surface modification method can enhance the uniformity of the inkjet-printed films by reducing the “coffee ring effect”. As a proof-of-concept demonstration, reduced graphene oxide-based gas sensors, which were flexible, ultra-lightweight, and miniature-sized, were fully-inkjet-printed on surface modified Kapton HN films and tested for their sensitivity to dimethyl methylphosphonate (a nerve agent simulant). Such fabricated sensors survived a Scotch-tape peel test and were found insensitive to repeated bending to a small 0.5 cm radius.

  14. The method of manufacture of nylon dental partially removable prosthesis using additive technologies

    Kashapov, R. N.; Korobkina, A. I.; Platonov, E. V.; Saleeva, G. T.

    2014-12-01

    The article is devoted to the topic of creating new methods of dental prosthesis. The aim of this work is to investigate the possibility of using additive technology to create nylon prosthesis. As a result of experimental studies, was made a sample of nylon partially removable prosthesis using 3D printing has allowed to simplify, accelerate and reduce the coat of manufacturing high-precision nylon dentures.

  15. Effect of gamma irradiation on nylon 6 films : swelling study

    Singh, L.P.; Chaudhuri, N.K.

    1980-01-01

    This paper reports on swelling studies of γ-irradiated nylon 6 films undertaken to investigate the effects of γ-irradiation in finer details. Benzyl alcohol has been used as the swelling agent. The kinetics of weight swelling of γ-irradiated nylon 6 films in benzyl alcohol was studied at different irradiation doses in the range 0 - 28.8 Mrad. It is observed that with increasing irradiation dose upto 14.4 Mrad the swelling, and hence the diffusion process are retarded; moreover, the sigmoidal nature of the percentage weight swelling vs (time)sup(1/2) plot is augmented. Above this critical dose the swelling and diffusion processes are accelerated. Besides, the sigmoidal behaviour recedes and is converted into linear behaviour at 28.8 Mrad. This behaviour indicates that a relaxation-controlled non-Fickian diffusion process is at work below 28.8 Mrad while at 28.8 Mrad a Fickian process is established. A significant effect on the equilibrium swelling in benzyl alcohol is observed. The plot of equilibrium weight swelling vs irradiation dose at 23deg C shows an initial decrease of swelling upto 3.6 Mrad at which swelling starts decreasing at accelerated rate in the dose range 3.6 - 7.6 Mrad. The rate slows down appreciably between 7.00 and 14.4 Mrad, above which there is a rapid fall. The results are correlated with scission and crosslinking processes through relative viscosity determination of formic acid solutions of the irradiated samples. It is established by combining viscosity data with kinetics and equilibrium swelling data that, besides scission, crosslinking processes are also at work in nylon 6 in the irradiation dose range 0 - 3.6 Mrad. It has been possible to bring out this point because the swelling technique seems to be preferentially sensitive towards crosslinking. (author)

  16. Contribution to the study of metallic impurities diffusion in a polymer film (KAPTON) under and out of irradiation; Contribution a l`etude de la diffusion d`impuretes metalliques dans un film polymere (KAPTON) sous et hors irradiation

    Marin, N

    1995-12-18

    The main topic of this work is the diffusion behaviour in the polymer film Kapton, under and out of irradiation, of metallic coatings with different reactivity (copper, nickel, titanium) deposited by sputtering. The analysis of diffusion profiles has been performed by backscattering spectrometry, which, in association with cross-section microscopy, allows to connect the diffusion behaviour to the microscopic structure of the metal/Kapton interface. Generally speaking, the study under thermal annealing shows the importance of peculiarities of commercials polymers. In particular, additional elements they contain are liable to modify their surface characteristics and, as a consequence, diffusion. So, unlike observations in model polyimides, we show that even weakly reactive metals do not diffuse inside the polymer. Besides, there exists an energy threshold of Ar{sup +} used for sputtering, above which copper layers become very stable and so come up to industry`s expectation. The study under irradiation gives evidence for copper diffusion under irradiation, resulting in 15 mn mean radius spherical clusters inside the modified polymer. This fast diffusion is shown to be due to the concomitant effect of nuclear collisions and temperature. This study is also the opportunity to show dramatic radiation-induced effects in Kapton, more particularly a large modification of mechanical and optical properties with the loss of more volatile elements (H, N,O). With regard to methodology, this study shows the strong ambiguity in the RBS spectrum interpretation in the case of lateral non-uniformity, and we propose a model giving access to the statistical distribution of the non-uniform property of the target. (author). 262 refs., 99 figs., 8 appends.

  17. Metabolic Engineering toward Sustainable Production of Nylon-6.

    Turk, Stefan C H J; Kloosterman, Wigard P; Ninaber, Dennis K; Kolen, Karin P A M; Knutova, Julia; Suir, Erwin; Schürmann, Martin; Raemakers-Franken, Petronella C; Müller, Monika; de Wildeman, Stefaan M A; Raamsdonk, Leonie M; van der Pol, Ruud; Wu, Liang; Temudo, Margarida F; van der Hoeven, Rob A M; Akeroyd, Michiel; van der Stoel, Roland E; Noorman, Henk J; Bovenberg, Roel A L; Trefzer, Axel C

    2016-01-15

    Nylon-6 is a bulk polymer used for many applications. It consists of the non-natural building block 6-aminocaproic acid, the linear form of caprolactam. Via a retro-synthetic approach, two synthetic pathways were identified for the fermentative production of 6-aminocaproic acid. Both pathways require yet unreported novel biocatalytic steps. We demonstrated proof of these bioconversions by in vitro enzyme assays with a set of selected candidate proteins expressed in Escherichia coli. One of the biosynthetic pathways starts with 2-oxoglutarate and contains bioconversions of the ketoacid elongation pathway known from methanogenic archaea. This pathway was selected for implementation in E. coli and yielded 6-aminocaproic acid at levels up to 160 mg/L in lab-scale batch fermentations. The total amount of 6-aminocaproic acid and related intermediates generated by this pathway exceeded 2 g/L in lab-scale fed-batch fermentations, indicating its potential for further optimization toward large-scale sustainable production of nylon-6.

  18. The use of nylon cable ties to repair rib fractures in neonatal foals

    Downs, Chris; Rodgerson, Dwayne

    2011-01-01

    Commercially available nylon cable ties were used as a method of internal fixation for displaced rib fractures in 8 equine neonates. The procedure was effective, well-tolerated, rapid, and inexpensive. The use of nylon cable ties as internal fixation for displaced rib fractures in foals is an effective surgical procedure.

  19. 21 CFR 175.360 - Vinylidene chloride copolymer coatings for nylon film.

    2010-04-01

    ... film. 175.360 Section 175.360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... coatings for nylon film. Vinylidene chloride copolymer coatings identified in this section and applied on nylon film may be safely used as food-contact surfaces, in accordance with the following prescribed...

  20. Assessment of the anti-biofouling potentials of a copper iodide-doped nylon mesh.

    Sato, Tetsuya; Fujimori, Yoshie; Nakayama, Tsuruo; Gotoh, Yasuo; Sunaga, Yoshihiko; Nemoto, Michiko; Matsunaga, Tadashi; Tanaka, Tsuyoshi

    2012-08-01

    We propose a copper iodide (CuI)-doped nylon mesh prepared using polyiodide ions as a precursor toward anti-biofouling polymer textile. The CuI-doped nylon mesh was subjected to the prevention of biofouling in marine environments. The attachment of the marine organisms was markedly inhibited on the CuI-doped nylon mesh surface until 249 days. Scanning electron microscopy-energy dispersive X-ray analysis indicated that copper compounds were maintained in the nylon mesh after the field experiment, although copper content in the nylon mesh was reduced. Therefore, the copper ions slowly dissolved from nylon mesh will contribute to the long-term prevention of biofouling. Furthermore, electron spin resonance analysis revealed the generation of reactive oxygen species (ROS) from CuI-doped nylon mesh after the field experiment. One of the possibilities for toxic action of copper ions will be the direct effect of Cu+ -induced ROS on biofilm forming on nylon mesh surface. The proposed polymer textile can be applied to fishing and aquafarming nets, mooring rope for ship, or silt fence to restrict polluted water in marine environments.

  1. Effect of Nylon Bag and Protozoa on In Vitro Corn Starch Disappearance

    Zwieten, van J.T.; Vuuren, van A.M.; Dijkstra, J.

    2008-01-01

    An in vitro experiment was carried out to study whether the presence of protozoa in nylon bags can explain the underestimation of the in situ degradation of slowly degradable starch. Corn of a high (flint) and a low (dent) vitreousness variety was ground over a 3-mm screen, weighed in nylon bags

  2. Contribution to the study of metallic impurities diffusion in a polymer film (KAPTON) under and out of irradiation

    Marin, N.

    1995-01-01

    The main topic of this work is the diffusion behaviour in the polymer film Kapton, under and out of irradiation, of metallic coatings with different reactivity (copper, nickel, titanium) deposited by sputtering. The analysis of diffusion profiles has been performed by backscattering spectrometry, which, in association with cross-section microscopy, allows to connect the diffusion behaviour to the microscopic structure of the metal/Kapton interface. Generally speaking, the study under thermal annealing shows the importance of peculiarities of commercials polymers. In particular, additional elements they contain are liable to modify their surface characteristics and, as a consequence, diffusion. So, unlike observations in model polyimides, we show that even weakly reactive metals do not diffuse inside the polymer. Besides, there exists an energy threshold of Ar + used for sputtering, above which copper layers become very stable and so come up to industry's expectation. The study under irradiation gives evidence for copper diffusion under irradiation, resulting in 15 mn mean radius spherical clusters inside the modified polymer. This fast diffusion is shown to be due to the concomitant effect of nuclear collisions and temperature. This study is also the opportunity to show dramatic radiation-induced effects in Kapton, more particularly a large modification of mechanical and optical properties with the loss of more volatile elements (H, N,O). With regard to methodology, this study shows the strong ambiguity in the RBS spectrum interpretation in the case of lateral non-uniformity, and we propose a model giving access to the statistical distribution of the non-uniform property of the target. (author). 262 refs., 99 figs., 8 appends

  3. Interfacial enhancement of carbon fiber/nylon 12 composites by grafting nylon 6 to the surface of carbon fiber

    Hui, Chen; Qingyu, Cai; Jing, Wu; Xiaohong, Xia; Hongbo, Liu; Zhanjun, Luo

    2018-05-01

    Nylon 6 (PA6) grafted onto carbon fiber (CF) after chemical oxidation treatment was in an attempt to reinforce the mechanical properties of carbon fiber composites. Scanning electronic microscopy (SEM), Fourier transform infrared analysis (FT-IR), X-ray photoelectron spectroscope (XPS) and thermogravimetric analysis (TG) were selected to characterize carbon fibers with different surface treated. Experimental results showed that PA6 was grafted uniformly on the fiber surface through the anionic polymerization. A large number of functional groups were introduced to the fiber surface and the surface roughness was increased. After grafting PA6 on the oxidized carbon fibers, it played an important role on improving the interfacial adhesion between the fibers and the matrix by improving PA12 wettability, increasing chemical bonding and mechanical interlocking. Compared with the desized CF composites, the tensile strength of PA6-CF/PA12 composites was increased by 30.8% from 53.9 MPa to 70.2 MPa. All results indicated that grafting PA6 onto carbon fiber surface was an effective method to enhance the mechanical strength of carbon fiber/nylon 12 composites.

  4. The thermal degradation of poly(iso-butyl methacrylate and poly(sec-butyl methacrylate

    IVANKA G. POPOVIC

    2000-12-01

    Full Text Available The non-oxidative thermal degradation of poly(iso-butyl methacrylate and poly(sec-butyl methacrylate was investigated by studying changes in the polymer residue. Due to the different number of b-hydrogens in their ester substituents, these two polymeric isomers behave differently when subjected to elevated temperatures. Poly(iso-butyl methacrylate degrades quantitatively by depolymerisation with zip lengths of the same order of magnitude as those of poly(methyl methacrylate. Poly(sec-butyl methacrylate degrades by a combined degradation mechanism of depolymerisation and de-esterification. De-esterification becomes a significant thermolysis route at temperatures higher than 240°C.

  5. Moisture dependence of positron annihilation spectra in nylon-6

    Singh, J.J.; Clair, T.L.S.; Holt, W.H.; Mock, W. Jr.

    1984-01-01

    Positron annihilation time spectra have been measured in nylon-6 specimens as a function of their moisture content. The measured average longlife component lifetime values are: 1722 +- 47 ps (dry), 1676 +- 40 ps (14.6% saturation value), 1718 +- 26 ps (29.3% saturation value), 1720 +- 35 ps (50% of saturation value), 1857 +- 35 ps (78.1% of saturation value) and 1936 +- 57 ps (saturated). It is noted that the longlife component lifetime at first decreases and then increases with increasing moisture content in the specimens. This behavior is quite different from that observed in earlier studies of various epoxy, polyamide, and polyimide materials, where the longlife component lifetime decreased linearly with increasing moisture content. The longlife component intensity on the other hand, decreases steadily as the moisture content increases from 0 to 100% of the saturation value. A possible explanation for these anomalous features is discussed. (orig.)

  6. Enterprise simulation analysis of the nylon jacket pipeline

    Chandra, Charu [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Nastasi, Anthony [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Powell, Dennis R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ostic, James K. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    1996-12-01

    The purpose of this study was to identify ways in which time and cost might be removed from the production of L. L. Bean’s® Warm-up Jacket through systems analysis and the application of supply chain management principles such as coordination and integration. The first three sections of this report provide an introduction, study objectives and a definition of generic supply chain problems as well as those specific to the Nylon Jacket Pipeline (NJP) respectively. Section four outlines the supply chain design components that should be included in any pipeline analysis including a generic architecture and methodology. In section five, results specific to the NJP analysis are documented. Finally, the last three sections include the project’s activities, deliverables, recommendations and conclusions.

  7. Increasing Mechanical Properties of 2-D-Structured Electrospun Nylon 6 Non-Woven Fiber Mats

    Chunhui Xiang

    2016-04-01

    Full Text Available Tensile strength, Young’s modulus, and toughness of electrospun nylon 6 non-woven fiber mats were improved by increasing individual nanofiber strength and fiber–fiber load sharing. Single-walled carbon nanotubes (CNTs were used as reinforcement to increase the strength of the electrospun nylon 6 nanofibers. Young’s modulus, tensile strength, and toughness of the nylon 6 non-woven fiber mats electrospun from 20 wt % solutions increased 51%, 87%, and 136%, respectively, after incorporating 1 wt % CNTs into the nylon 6 nanofibers. Three methods were investigated to enhance fiber–fiber load sharing: increasing friction between fibers, thermal bonding, and solvent bonding. The addition of beaded nylon 6 nanofibers into the non-woven fiber mats to increase fiber-fiber friction resulted in a statistically significantly increase in Young’s modulus over comparable smooth non-woven fiber mats. After annealing, tensile strength, elongation, and toughness of the nylon 6 non-woven fiber mats electrospun from 20 wt % + 10 wt % solutions increased 26%, 28%, and 68% compared to those from 20 wt % solutions. Solvent bonding with formic acid vapor at room temperature for 30 min caused increases of 56%, 67%, and 39% in the Young’s modulus, tensile strength, and toughness of non-woven fiber mats, respectively. The increases attributed to increased individual nanofiber strength and solvent bonding synergistically resulted in the improvement of Young’s modulus of the electrospun nylon 6 non-woven fiber mats.

  8. Preparation of a novel KCC-1/nylon 6 nanocomposite via electrospinning technique

    Aghakhani, Ali [Material and Energy Research Center, Department of Semiconductors (Iran, Islamic Republic of); Kazemi, Ensiyeh; Kazemzad, Mahmood, E-mail: m-kazemzad@merc.ac.ir [Material and Energy Research Center, Department of Energy (Iran, Islamic Republic of)

    2015-10-15

    In this research, a novel nanofibrous composite of KCC-1/nylon 6 was prepared using electrospinning techniques. First, fibrous silica nanospheres (KCC-1) were synthesized via conventional polycondensation method with a new solvent system. The scanning electron microscopy (SEM) images showed a spongy spherical morphology with a uniform distribution of particle sizes and an average diameter of around 305 nm. Synthesized KCC-1 nanospheres are considered as mesoporous materials due to their high BET specific surface area of 576 m{sup 2} g{sup −1} and BJH average pore diameter of 3.28 nm. The KCC-1/nylon 6 composite was fabricated by preparing a dispersion of nanosilica (10–50 % w/w) in a solution of nylon 6 (15 % w/v) in formic acid. Upon applying a high voltage, the nonwoven electrospun KCC-1/nylon 6 composite nanofibers were obtained. The KCC-1 nanospheres were arranged in line along the nylon 6 fibers like rosary beads wrapped in the polymer. Based on the SEM images, we obtained a well-distributed nanocomposite even at higher silica content. The prepared KCC-1/nylon 6 composite showed 29–55 % higher BET specific surface area compared with pure nylon 6 nanofibers which makes it a good candidate to be used as a sorbent material for environmental or drug delivery applications.

  9. Microstructural characterization of PAN based carbon fiber reinforced nylon 6 polymer composites

    Munirathnamma, L. M.; Ningaraju, S.; Kumar, K. V. Aneesh; Ravikumar, H. B.

    2018-04-01

    Microstructural characterization of nylon 6/polyacrolonitrile based carbon fibers (PAN-CFs) of 10 to 40 wt% has been performed by positron lifetime technique (PLT). The positron lifetime parameters viz., o-Ps lifetime (τ3), o-Ps intensity (I3) and fractional free volume (Fv) of nylon 6/PAN-CF composites are correlated with the mechanical properties viz., Tensile strength and Young's modulus. The Fv show negative deviation with the reinforcement of 10 to 40 wt% of PAN-CF from the linear additivity relation. The negative deviation in nylon 6/PAN-CF composite suggests the induced molecular packing due to the chemical interaction between the polymeric chains of nylon 6 and PAN-CF. This is evident from Fourier Transform Infrared Spectrometry (FTIR) studies. The FTIR results suggests that observed negative deviation in PALS results of nylon 6/PAN-CF reinforced polymer composites is due to the induced chemical interaction at N-H-O sites. The improved tensile strength (TS) and Young's modulus (YM) in nylon 6/PAN-CF reinforced polymer composites is due to AS4C (surface treated and epoxy coated) PAN-CF has shown highest adhesion level due to better stress transfer between nylon 6 and PAN-CF.

  10. Study on the Tribological Properties of MC Nylon Composites Filled with Hydraulic Oil

    Yuan, S.; Li, Y.; Wen, J.; Yin, L.; Zhang, Q.

    2018-03-01

    Mechanical parts utilized in machinery, such as nylon slider and pulley, should have certain mechanical properties and good tribological properties, so that equipments’ stability and smoothness can be assured. A kind of MC nylon (monomer cast nylon) composites filled with hydraulic oil was studied in this paper. The addition of hydraulic oil changed nylon’s mechanical properties and tribological properties significantly, and improved the material’s toughness and coefficient of friction. The composites have excellent strength, toughness and relatively low coefficient of friction when the content of the hydraulic oil is 4wt%.

  11. Use of Brazilian clay in nylon 6 with different molecular weight nanocomposites

    Araujo, Edcleide Maria; Paz, Rene Anisio; Melo, Tomas Jeferson Alves; Leite, Amanda Melissa Damiao; Barbosa, Renata; Ito, Edson Noriyuki

    2009-01-01

    The effect of nylon 6 (Ny6) molecular weight on the development of polymer/layered silicates nanocomposites prepared by the melt intercalation technique was studied in this work. The nylon6/organoclay nanocomposites were prepared in the counter-rotational twin screw extruder. The results of torque rheometry showed that the presence of organoclay in the nylon 6 increased the torque. The results of X-ray diffraction (XRD) and transmission electron microscopy (TEM) showed exfoliated and/or partially exfoliated structures. (author)

  12. Diseases and conditions falsely linked with “nylon teeth” myth: a ...

    The health care workers less likely linked nylon teeth with ... some instances, they invent methods to cure and/or prevent the children's .... (dentist + medical doctor + nurse + pharmacist) and non-medics (teacher + peasant + traditional healer).

  13. Synergism between two helper cell subpopulations characterized by different radiosensitivity and nylon adherence

    Agarossi, G.; Mancini, C.; Doria, G.

    1981-01-01

    The present work extends our previous results on the radiosensitivity of the helper cell function. Two helper cell subpopulations, 1 radiosensitive and the other radioresistant, have been demonstrated in the spleen of mice at different times after priming with HRBC. The radiosensitive subpopulation increases with the increasing time interval between carrier-priming and irradiation. The 2 cell subpopulations have been further characterized by different nylon adherence properties: radioresistant helper cells adhere to nylon wool, whereas radiosensitive cells pass through. The 2 cell subpopulations were separated by x-irradiation and nylon wool filtration, and their helper activity was assessed separately or after recombination. The results favor the notion that 2 functionally independent helper T cells, as characterized by different radiosensitivity and nylon adherence, participate synergistically in the helper activity of primed spleen cells

  14. Effect of nylon fiber on mechanical properties of cement based mortar

    Hanif, I. M.; Syuhaili, M. R. Noor; Hasmori, M. F.; Shahmi, S. M.

    2017-11-01

    An investigation has been carried out to study the effect of nylon fiber on the mechanical properties of cement based mortar after receiving large quantities of nylon waste. Subsequently, this research was conducted to compare the compressive, tensile and flexural strength of normal cement based mortar with nylon fiber cement based mortar. All samples using constant water-cement ratio of 0.63 and three different percentages of nylon fiber were added in the mixture during the samples preparation period which consists of 0.5%, 1.5% and 2.5% by total weight of cement based mortar. The results obtained with different nylon percentage marked an increases in compressive strength (up to 17%), tensile strength (up to 21%) and flexural strength (up to 13%) when compared with control cement based mortar samples. Therefore, the results obtained from this study shows that by using nylon fiber as additive material can improve the mechanical properties of the cement based mortar and at the same time produce a good sustainable product that can protects and conserve the marine environment.

  15. Nylon 6,6 Nonwoven Fabric Separates Oil Contaminates from Oil-in-Water Emulsions.

    Ryan A Ortega

    Full Text Available Industrial oil spills into aquatic environments can have catastrophic environmental effects. First responders to oil spills along the coast of the Gulf of Mexico in the southern United States have used spunbond nylon fabric bags and fences to separate spilled oil and oil waste from contaminated water. Low area mass density spunbond nylon is capable of sorbing more than 16 times its mass in low viscosity crude oil and more than 26 times its mass in higher viscosity gear lube oil. Nylon bags separated more than 95% of gear lube oil contaminate from a 4.5% oil-in-water emulsion. Field testing of spunbond nylon fences by oil spill first responders has demonstrated the ability of this material to contain the oily contaminate while allowing water to flow through. We hypothesize that the effectiveness of nylon as an oil filter is due to the fact that it is both more oleophilic and more hydrophilic than other commonly used oil separation materials. The nylon traps oil droplets within the fabric or on the surface, while water droplets are free to flow through the fabric to the water on the opposite side of the fabric.

  16. Preparation of antimicrobial MnO4--doped nylon-66 fibers with excellent laundering durability

    Zhang, Mingxing; Gao, Qianhong; Yang, Chenguang; Pang, Lijuan; Wang, Honglong; Li, Rong; Xing, Zhe; Hu, Jiangtao; Wu, Guozhong

    2017-11-01

    A highly effective antimicrobial nylon 66 fiber doped with permanganate ions was prepared via a simultaneous irradiation induced graft polymerization. The physicochemical properties of the fibers were carefully characterized by various techniques, including Fourier-transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and X-ray photoelectron spectroscopy, revealing that permanganate ions (about 1.48 mmol/g) have been successfully loaded onto the surface of the nylon 66 fibers. The antimicrobial activity of the modified nylon 66 fibers against Staphylococcus aureus and Candida albicans were investigated. Accelerated laundering tests and tensile tests were conducted to access the effect of laundering on the antimicrobial activity and the mechanical property of the modified nylon 66 fibers, respectively. All results indicate that we have prepared a new highly effective antimicrobial nylon 66 fiber (almost a 100% reduction in the number of S. aureus and C. albicans colonies). Furthermore, the modified nylon 66 fibers are durable, maintaining antimicrobial resistance after 100 commercial or domestic launderings and retaining its excellent mechanical property during preparation and laundering.

  17. Butylated caffeic acid: An efficient novel antioxidant

    G. Shi

    2017-09-01

    Full Text Available A novel antioxidant, butylated caffeic acid (BCA was rationally designed by adding a tert-butyl group to caffeic acid, which was synthesized at a high yield (36.2% from 2-methoxy-4-methylphenol by a four-step reaction including Friedel-Crafts alkylation, bromine oxidation, ether bond hydrolysis and Knoevenagel condensation. Its antioxidant capacity was much stronger than common commercial antioxidant tert-butyl hydroquinone (TBHQ and its mother compound, caffeic acid, in both rancimat and deep frying tests. When investigated via the DPPH method, the antioxidant capacity of BCA was almost equal to TBHQ, but lower than caffeic acid. BCA could be a potentially strong antioxidant, especially for food processing at high temperatures such as deep frying and baking.

  18. Butylated caffeic acid: An efficient novel antioxidant

    Shi, G.; Liao, X.; Olajide, T.M.; Liu, J.; Jiang, X.; Weng, X.

    2017-01-01

    A novel antioxidant, butylated caffeic acid (BCA) was rationally designed by adding a tert-butyl group to caffeic acid, which was synthesized at a high yield (36.2%) from 2-methoxy-4-methylphenol (1) by a four-step reaction including Friedel-Crafts alkylation, bromine oxidation, ether bond hydrolysis and Knoevenagel condensation. Its antioxidant capacity was much stronger than common commercial antioxidant tert-butyl hydroquinone (TBHQ) and its mother compound, caffeic acid, in both rancimat and deep frying tests. When investigated via the DPPH method, the antioxidant capacity of BCA was almost equal to TBHQ, but lower than caffeic acid. BCA could be a potentially strong antioxidant, especially for food processing at high temperatures such as deep frying and baking. [es

  19. Fracture Behavior in Nylon 6 Fibers. Ph.D. Thesis

    Lloyd, B. A.

    1972-01-01

    Electron paramagnetic resonance (EPR) techniques are used to determine the number of free radicals produced during deformation leading to fracture of nylon 6 fibers. A reaction rate molecular model is proposed to explain some of the deformation and bond rupture behavior leading to fracture. High-strength polymer fibers are assumed to consist of a sandwich structure of disordered and ordered regions along the fiber axis. In the disordered or critical flaw regions, tie chains connecting the ordered or crystalline block regions are assumed to have a statistical distribution in length. These chains are, therefore, subjected to different stresses. The effective length distribution was determined by EPR. The probability of bond rupture was assumed to be controlled by reaction-rate theory with a stress-aided activation energy and behavior of various loadings determined by numerical techniques. The model is successfully correlated with experimental stress, strain, and bond rupture results for creep, constant rate loadings, cyclic stress, stress relaxation and step strain tests at room temperature.

  20. Highly Stretchable Non-volatile Nylon Thread Memory

    Kang, Ting-Kuo

    2016-04-01

    Integration of electronic elements into textiles, to afford e-textiles, can provide an ideal platform for the development of lightweight, thin, flexible, and stretchable e-textiles. This approach will enable us to meet the demands of the rapidly growing market of wearable-electronics on arbitrary non-conventional substrates. However the actual integration of the e-textiles that undergo mechanical deformations during both assembly and daily wear or satisfy the requirements of the low-end applications, remains a challenge. Resistive memory elements can also be fabricated onto a nylon thread (NT) for e-textile applications. In this study, a simple dip-and-dry process using graphene-PEDOT:PSS (poly(3,4-ethylenedioxythiophene) polystyrene sulfonate) ink is proposed for the fabrication of a highly stretchable non-volatile NT memory. The NT memory appears to have typical write-once-read-many-times characteristics. The results show that an ON/OFF ratio of approximately 103 is maintained for a retention time of 106 s. Furthermore, a highly stretchable strain and a long-term digital-storage capability of the ON-OFF-ON states are demonstrated in the NT memory. The actual integration of the knitted NT memories into textiles will enable new design possibilities for low-cost and large-area e-textile memory applications.

  1. Experimental study of nylon fibre reinforced RC beams

    Ansari, A.A.; Jokhio, S.; Qazi, Attiq-ur-Rehman

    2002-01-01

    Six concrete beams reinforced with Nylon fibre strands placed in tensile zone as an alternative of steel bars have been tested. Fibre of 1.2 mm dia was used and 10 pieces were twisted together to form the strand; the number of turns being a parameter of study. This was done in order to over come the problem of bond, because the surface of fibre is very smooth and slippery. Two strands were used in each beam and in order to eliminate possibility of premature failure due to bond, specially designed End-Steel Anchorages were also tried. All the beams were 1000 mm long and 50 x 100 mm in cross section with an affective span of 900 mm. The tensile behaviors as well as moduli of the fibre itself were also determined. No shear reinforcement was used. The results are encourage and comparative financial study shows that this material holds promise for future use. However, more experimental study is needed. (author)

  2. Solvent effects on the magnetic shielding of tertiary butyl alcohol

    )4 and tetramethyl ammonium cation N(CH3)4(+) have also been presented. KEY WORDS: Solvent effects, Magnetic shielding, Tertiary butyl alcohol, Tertiary butyl amine, Continuum solvation calculations, Chemical shift estimation methods

  3. Reinforcement of nylon 6,6/nylon 6,6 grafted nanodiamond composites by in situ reactive extrusion

    Choi, Eun-Yeob; Kim, Kiho; Kim, Chang-Keun; Kang, Eunah

    2016-11-01

    Nanodiamond (ND), an emerging new carbon material, was exploited to reinforce nylon 6,6 (PA66) polymer composites. Surface modified nanodiamonds with acyl chloride end groups were employed to chemically graft into PA66, enhancing the interfacial adhesion and thus the mechanical properties. The ND grafted PA66 (PA66-g-ND) reinforced PA66 composite prepared by in situ reactive extrusion exhibited increased tensile strength and modulus. The tensile strength and modulus of PA66/3 wt.% PA66-g-ND composites were enhanced by 11.6 and 20.8%, respectively when compared to those of the bare PA66 matrix. Even the PA66/pristine ND composites exhibited enhanced mechanical properties. The PA66-g-ND and the homogeneously dispersed PA66-g-ND in PA66 matrix were examined using X-ray photoelectron spectroscopy, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy techniques. The mechanical properties and thermal conductivities of the nanodiamond incorporated PA66 composites were also explored. The enhanced mechanical properties and thermal conductivities of the PA66-g-ND/PA66 composites make them potential materials for new applications as functional engineered thermoplastics.

  4. Compound list: butylated hydroxyanisole [Open TG-GATEs

    Full Text Available butylated hydroxyanisole BHA 00156 ftp://ftp.biosciencedbc.jp/archive/open-tggates/...LATEST/Human/in_vitro/butylated_hydroxyanisole.Human.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/o...pen-tggates/LATEST/Rat/in_vivo/Liver/Single/butylated_hydroxyanisole.Rat.in_vivo.Liver.Single.zip ftp://ftp....biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Repeat/butylated_hydroxyanisole.Rat.in_vivo.Liver.Repeat.zip ...

  5. Intake of butylated hydroxyanisole and butylated hydroxytoluene and stomach cancer risk : results from analyses in the Netherlands : cohort study

    Botterweck, A.A.M.; Verhagen, H.; Goldbohm, R.A.; Kleinjans, J.; Brandt, P.A. van den

    2000-01-01

    Both carcinogenic and anticarcinogenic properties have been reported for the synthetic antioxidants butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). The association between dietary intake of BHA and BHT and stomach cancer risk was investigated in the Netherlands Cohort Study (NLCS)

  6. Nanoscale morphogenesis of nylon-sputtered plasma polymer particles

    Choukourov, Andrei; Shelemin, Artem; Pleskunov, Pavel; Nikitin, Daniil; Khalakhan, Ivan; Hanuš, Jan

    2018-05-01

    Sub-micron polymer particles are highly important in various fields including astrophysics, thermonuclear fusion and nanomedicine. Plasma polymerization offers the possibility to produce particles with tailor-made size, crosslink density and chemical composition to meet the requirements of a particular application. However, the mechanism of nucleation and growth of plasma polymer particles as well as diversity of their morphology remain far from being clear. Here, we prepared nitrogen-containing plasma polymer particles by rf magnetron sputtering of nylon in a gas aggregation cluster source with variable length. The method allowed the production of particles with roughly constant chemical composition and number density but with the mean size changing from 80 to 320 nm. Atomic Force Microscopy with super-sharp probes was applied to study the evolution of the particle surface topography as they grow in size. Height–height correlation and power spectral density functions were obtained to quantify the roughness exponent α  =  0.78, the growth exponent β  =  0.35, and the dynamic exponent 1/z  =  0.50. The set of critical exponents indicates that the particle surface evolves in a self-affine mode and the overall particle growth is caused by the accretion of polymer-forming species from the gas phase and not by coagulation. Redistribution of the incoming material over the surface coupled with the inhomogeneous distribution of inner stress is suggested as the main factor that determines the morphogenesis of the plasma polymer particles.

  7. Nylon filament coated with paraffin for intraluminal permanent middle cerebral artery occlusion in rats.

    Zuo, Xia-Lin; Wu, Ping; Ji, Ai-Min

    2012-06-21

    A variety of intraluminal nylon filament has been used in rat middle cerebral artery occlusion (MCAO) models. However the lesion extent and its reproducibility vary among laboratories. The properties of nylon filament play a part of reasons for these variations. In the present study, we used paraffin-coated nylon filament for rat MCAO model, tested the effects and advanced improvement for making the rat MCAO. Forty male Sprague-Dawley (SD) rats were randomized into two groups, MCAO with traditional uncoated nylon filament (uMCAO) and MCAO with paraffin-coated nylon filament (cMCAO), three rats as normal group and sham group respectively. Assessment included mortality rates, model success rates, neurological deficit evaluation, and infarct volume. The study showed two rats died in uMCAO group, no rat died in cMCAO group within the 12h. The model success rate of uMCAO was 100%, while the uMCAO group was 55% (n=20, two died within 12h, seven rats were excluded as the brain slices showed no TTC staining due to subarachanoid hemorrhage). Neurological evaluation demonstrated group cMCAO had more worse neurological outcomes than group uMCAO, and the difference was statistically signification (pparaffin-coated nylon filament intraluminal occlusion provide better occlusion of middle cerebral artery than the uncoated nylon filament, improve the consistent of model, and raise the success rate to reduce the number of experimental animals. These positive results are much encouraging and interesting. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  8. Recovering/recycling of butyl and halogenated butyl rubber via ionizing radiation

    Martin, Sandra Regina Scagliusi

    2013-01-01

    Polymeric materials (plastics and rubbers) attain a continuous and raising proportion of urban and industrial scraps discarded in landfills; their impact on environment are more and more concerning. The implementation of new technologies in order to reduce impacts of plastic waste on the environment, at an effective cost, proved to be a great problem, due to inherent complexity for polymers re-using. Ionizing radiation is capable to modify structure and properties of polymeric material. Butyl and halobutyl rubbers have been used within a comprehensive scale, applications such as tires spare parts and diverse artifacts. The major high energy photon effect, as gamma-rays in butyl and halo butyl rubbers consists in free-radicals generation along changes in mechanical properties.This work aims to the development of controlled degradation processes (devulcanization) of butyl and halo butyl (chlorine and bromine) rubbers, in order to characterize their availability for transformation and modification of properties. Experimental results obtained showed that butyl and halobutyl rubbers,irradiated at 25 kGy and further sheared, are able to be used as an initial point for mixtures with pristine. (author)

  9. A novel wood flour-filled composite based on microfibrillar high-density polyethylene (HDPE)/Nylon-6 blends.

    Liu, Hongzhi; Yao, Fei; Xu, Yanjun; Wu, Qinglin

    2010-05-01

    A novel wood flour (WF)-filled composite based on the microfibrillar high-density polyethylene (HDPE) and Nylon-6 co-blend, in which both in situ formed Nylon-6 microfibrils and WF acted as reinforcing elements, was successfully developed using a two-step extrusion method. At the 30wt.% WF loading level, WF-filled composite based on the microfibrillized HDPE/Nylon-6 blend exhibited higher strengths and moduli than the corresponding HDPE-based composite. The incorporation of WF reduced short-term creep response of HDPE matrix and the presence of Nylon-6 microfibrils further contributed to the creep reduction. Copyright 2009 Elsevier Ltd. All rights reserved.

  10. Nylon and teflon scribe effect on NBR to Chemlok 233 and NBR to NBR bond interfaces

    Jensen, S. K.

    1990-01-01

    A study was requested by Manufacturing Engineering to determine what effects marking with nylon (6/6) and Teflon scribes may have on subsequent bonding. Witness panel bond specimens were fabricated by the development lab to test both acrylonitrile butadiene rubber (NBR) to Chemlok and NBR to NBR after controlled exposure. The nylon rod used as a scribe tool demonstrates virtually no bond deterioration when used to scribe lines on either the Chemlok to NBR surfaces or the NBR to NBR interface. Lab test results indicate that the nylon rod-exposed samples produce tensile and peel values very similar to the control samples and the Teflon exposed samples produce tensile and peel values much lower than the control samples. Visual observation of the failure surfaces of the tested samples shows that Teflon scribing produces an obvious contamination to the surface and the nylon produces no effect. Photographs of test samples are provided. It is concluded that Teflon stock used as a scribe tool on a Chemlok 233 to NBR surface or an NBR to NBR surface has a detrimental effect on the bond integrity on either of these bond interfaces. Therefore, it is recommended that the nylon rod continue to be used where a scribe line is required in the redesigned solid rocket motor segment insulation layup operations. The use of Teflon scribes should not be considered.

  11. Lichen amyloidosis induced on the upper back by long-term friction with a nylon towel.

    Yoshida, Aki; Takahashi, Kazuhiro; Tagami, Hachiro; Akasaka, Toshihide

    2009-01-01

    Primary localized cutaneous amyloidosis can take several clinical forms. In Asia, macular amyloidosis caused by prolonged friction from a rough nylon towel or brush is common, and macular amyloidosis and lichen amyloidosis occasionally occur together, as so-called biphasic amyloidosis. We report herein the case of an 83-year-old Japanese man with lichen amyloidosis caused by prolonged nylon towel friction. This patient presented with unique symmetrical papular lesions on the upper back and shoulders. Lesions comprised slightly shiny, brownish, fine uniform papules approximately 0.5 mm in diameter, showing a partially linear, annular or rippled arrangement. Although this case was caused by prolonged nylon towel friction, no coexisting macular lesions could be found. To the best of our knowledge, this represents the first case of lichen amyloidosis induced by nylon towel friction in the absence of the macular amyloidosis that is usually observed in such cases. We instructed the patient to stop the habit of nylon towel rubbing and prescribed a topical steroid ointment and cepharanthine. After 6 months of treatment, papular lesions became clearly flatter.

  12. Modification of nylon-6 fibres by radiation-induced graft polymerisation of vinylbenzyl chloride

    Ting, T.M.; Nasef, Mohamed Mahmoud; Hashim, Kamaruddin

    2015-01-01

    Modification of nylon-6 fibres by radiation-induced graft copolymerisation (RIGP) of vinylbenzyl chloride (VBC) using the preirradiation method was investigated. A number of grafting parameters such as type of solvent, total dose, monomer concentrations, reaction temperature and reaction time were studied to obtain desired degree of grafting (DG). The DG was found to be a function of reaction parameters and achieved a maximum value of 130 wt% at 20 vol% VBC concentration in methanol, 300 kGy dose, 30 °C temperature and 3 h reaction time. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD) were employed to evaluate the chemical, morphological and structural changes that occurred in the grafted fibres, respectively. Thermogravimetric analysis (TGA) was also applied to determine the thermal stability, whereas differential scanning calorimeter (DSC) and universal mechanical tester were used to analyse respective thermal and mechanical properties of the grafted fibres. The results of these analyses provide strong evidence for successful grafting of VBC onto nylon-6, and the variation in the properties of the grafted fibres depends on DG. - Highlights: • Modification of nylon-6 fibres by radiation induced grafting of VBC in methanol. • Establishment of relations between DG and reaction parameters. • Evidence of VBC grafting was provided by FTIR, SEM, XRD, DSC and TGA. • The properties of VBC-grafted nylon-6 fibres depend on DG. • Amendable VBC-grafted nylon-6 fibres retain favourable properties

  13. Toughening and healing of composites by CNTs reinforced copolymer nylon micro-particles

    Kostopoulos, V.; Kotrotsos, A.; Tsokanas, P.; Tsantzalis, S.

    2018-02-01

    In this work, nylon micro-particles, both undoped and doped with multiwall carbon nanotubes played the role of the self-healing agent into carbon fibre/epoxy composites (CFRPs). These micro-particles were blended with epoxy matrix and the resulting mixture was used for the composites fabrication. Three types of composites were manufactured; the reference CFRP and the modified CFRPs with undoped and doped nylon micro-particles. After manufacturing, these composites were tested under mode I and II fracture loading conditions and it was shown that the interlaminar fracture toughness characteristics of both nylon modified composites were significantly increased. After first fracture, healing process was activated for the tested nylon modified samples and revealed high fracture toughness characteristics recovery. Morphology examinations supported the results and elucidated the involved toughening and failure mechanisms. Finally, the in-plane mechanical and thermo-mechanical properties of all the composites were characterized for identifying possible knock-down effects due to the nylon modification of composites.

  14. Investigating the Effects of Nanoclay and Nylon Fibers on the Mechanical Properties of Asphalt Concrete

    Hasan Taherkhani

    2016-12-01

    Full Text Available This paper describes the effects of reinforcement by randomly distributed nylon fibers and addition of nanoclay on some engineering properties of a typical asphalt concrete. The properties of asphalt concrete reinforced by different percentages of 25 mm nylon fibers have been compared with those of the mixtures containing different percentages of nanoclay and those in which both the fibers and nanoclay have been included. Engineering properties, including Marshall stability, resilient modulus, dynamic creep and fatigue life have been studied. Nylon fibers have been used in different percentages of 0.1, 0.2, 0.3 and 0.4% (by the weight of total mixture, and nanoclay has been used in 2, 4 and 7% (by the weight of bitumen. It is found that the addition of fibers is more effective than the nanoclay for increasing the resistance against fatigue cracking. However, nanoclay improves the resistance of the mixture against permanent deformation better than the nylon fibers. The results also show that the mixture reinforced by 0.4% of nylon fibers and containing 7% of nanoclay has the highest resilient modulus, Marshall stability and fatigue life. However, the mixture containing only 7% of nanoclay has the highest resistance against permanent deformation.

  15. The effect of nylon nanofibers on the dynamic behaviour and the delamination resistance of GFRP composites

    Garcia Cristobal

    2018-01-01

    Full Text Available Vibrations are responsible for a considerable number of accidents in aircrafts, bridges and other civil engineering structures. Therefore, there is a need to reduce the vibrations on structures made of composite materials. Delamination is a particularly dangerous failure mode for composite materials because delaminated composites can lose up to 60% of their strength and stiffness and still remain unchanged. One of the methods to suppress vibrations and preventing delamination is to incorporate nanofibers into the composite laminates. The aim of the present work is to investigate how nylon nanofibers affect the dynamic behaviour and delamination resistance of glass fibre reinforced polymer (GFRP composites. Experiments and numerical simulations using finite element modelling (FEM analysis are used to estimate the natural frequencies, the damping ratio and inter-laminar strength in GFRP composites with and without nylon nanofibers. It is found that the natural frequencies of the nylon nano-modified composites do not change significantly as compared to the traditional composites. However, nano-modified composites demonstrated a considerable increase in damping ratio and inter-laminar shear strength due to the incorporation of nylon nanofibers. This work contributes to the knowledge about the mechanical and dynamic properties of glass fibre reinforced polymer (GFRP composites with nylon nanofibers.

  16. Polyaniline-nylon-6 electrospun nanofibers for headspace adsorptive microextraction

    Bagheri, Habib; Aghakhani, Ali

    2012-01-01

    Highlights: ► Polyaniline–polyamide nanofiber mat was fabricated by electrospinning technology. ► Electrospun nanofiber was used for extraction of chlorobenzenes from aquatic media. ► A method based on headspace adsorptive microextraction and GC–MS was developed. - Abstract: A headspace adsorptive microextraction technique was developed using a novel polyaniline-nylon-6 (PANI-N6) nanofiber sheet, fabricated by electrospinning. The homogeneity and the porosity of the prepared PANI-N6 sheet were studied using the scanning electron microscopy (SEM) and nanofibers diameters were found to be around 200 nm. The novel nanofiber sheet was examined as an extracting medium to isolate some selected chlorobenzenes (CBs), as model compounds, from aquatic media. The extracted analytes were desorbed using μL-amounts of solvent and eventually an aliquot of extractant was injected into gas chromatography–mass spectrometry (GC–MS). Various parameters affecting the extraction and desorption processes were optimized. The developed method proved to be convenient and offers sufficient sensitivity and a good reproducibility. Limits of detection achieved for CBs with the developed analytical procedure ranged from 19 to 33 ng L −1 , while limits of quantification were from 50 to 60 ng L −1 . The relative standard deviations (RSD) at a concentration level of 0.1 ng mL −1 and 1 ng mL −1 were in the range of 8–14% and 5–11% (n = 3), respectively. The calibration curves of analytes were investigated in the range of 50–1000 ng L −1 and R 2 between 0.9739 and 0.9932 were obtained. The developed method was successfully applied to the extraction of selected CBs from tap and river water samples. The relative recovery (RR) percentage obtained for the spiked real water samples at 0.1 ng mL −1 and 1 ng mL −1 level were 93–103% and 95–104%, respectively. The whole procedure showed to be conveniently applicable and quite easy to handle.

  17. Polyaniline-nylon-6 electrospun nanofibers for headspace adsorptive microextraction

    Bagheri, Habib, E-mail: bagheri@sharif.edu [Environmental and Bio-Analytical Laboratories, Department of Chemistry, Sharif University of Technology, P.O. Box 11365-9516, Tehran (Iran, Islamic Republic of); Aghakhani, Ali [Environmental and Bio-Analytical Laboratories, Department of Chemistry, Sharif University of Technology, P.O. Box 11365-9516, Tehran (Iran, Islamic Republic of)

    2012-02-03

    Highlights: Black-Right-Pointing-Pointer Polyaniline-polyamide nanofiber mat was fabricated by electrospinning technology. Black-Right-Pointing-Pointer Electrospun nanofiber was used for extraction of chlorobenzenes from aquatic media. Black-Right-Pointing-Pointer A method based on headspace adsorptive microextraction and GC-MS was developed. - Abstract: A headspace adsorptive microextraction technique was developed using a novel polyaniline-nylon-6 (PANI-N6) nanofiber sheet, fabricated by electrospinning. The homogeneity and the porosity of the prepared PANI-N6 sheet were studied using the scanning electron microscopy (SEM) and nanofibers diameters were found to be around 200 nm. The novel nanofiber sheet was examined as an extracting medium to isolate some selected chlorobenzenes (CBs), as model compounds, from aquatic media. The extracted analytes were desorbed using {mu}L-amounts of solvent and eventually an aliquot of extractant was injected into gas chromatography-mass spectrometry (GC-MS). Various parameters affecting the extraction and desorption processes were optimized. The developed method proved to be convenient and offers sufficient sensitivity and a good reproducibility. Limits of detection achieved for CBs with the developed analytical procedure ranged from 19 to 33 ng L{sup -1}, while limits of quantification were from 50 to 60 ng L{sup -1}. The relative standard deviations (RSD) at a concentration level of 0.1 ng mL{sup -1} and 1 ng mL{sup -1} were in the range of 8-14% and 5-11% (n = 3), respectively. The calibration curves of analytes were investigated in the range of 50-1000 ng L{sup -1} and R{sup 2} between 0.9739 and 0.9932 were obtained. The developed method was successfully applied to the extraction of selected CBs from tap and river water samples. The relative recovery (RR) percentage obtained for the spiked real water samples at 0.1 ng mL{sup -1} and 1 ng mL{sup -1} level were 93-103% and 95-104%, respectively. The whole procedure showed

  18. Modeling and flow analysis of pure nylon polymer for injection molding process

    Nuruzzaman, D M; Kusaseh, N; Basri, S; Hamedon, Z; Oumer, A N

    2016-01-01

    In the production of complex plastic parts, injection molding is one of the most popular industrial processes. This paper addresses the modeling and analysis of the flow process of the nylon (polyamide) polymer for injection molding process. To determine the best molding conditions, a series of simulations are carried out using Autodesk Moldflow Insight software and the processing parameters are adjusted. This mold filling commercial software simulates the cavity filling pattern along with temperature and pressure distributions in the mold cavity. In the modeling, during the plastics flow inside the mold cavity, different flow parameters such as fill time, pressure, temperature, shear rate and warp at different locations in the cavity are analyzed. Overall, this Moldflow is able to perform a relatively sophisticated analysis of the flow process of pure nylon. Thus the prediction of the filling of a mold cavity is very important and it becomes useful before a nylon plastic part to be manufactured. (paper)

  19. Filtration through nylon membranes negatively affects analysis of arsenic and phosphate by the molybdenum blue method

    Heimann, Axel Colin; Jakobsen, Rasmus

    2007-01-01

    Filtering synthetic arsenic- or phosphate-containing solutions (1.5-47.6 mu mol/L) with nylon syringe filters significantly reduced absorbances (by 6-74%) when analyzed with the colorimetric molybdenum blue method. Filtering the same solutions with cellulose acetate syringe filters yielded...... no significant differences as compared to unfiltered controls. The detrimental effect of nylon membranes was also observed when pure Milli-Q water was filtered and Subsequently spiked with arsenic(III) or phosphate suggesting that some compound(s) eluting from the filter membranes interfere with the color...... formation in the assay. Consequently, we caution against using nylon filters when filtering water samples for the determination of arsenic or phosphate with the molybdenum blue method....

  20. Micro-nano hierarchically structured nylon 6,6 surfaces with unique wettability.

    Zhang, Liang; Zhang, Xiaoyan; Dai, Zhen; Wu, Junjie; Zhao, Ning; Xu, Jian

    2010-05-01

    A micro-nano hierarchically structured nylon 6,6 surface was easily fabricated by phase separation. Nylon 6,6 plate was swelled by formic acid and then immersed in a coagulate bath to precipitate. Micro particles with nano protrusions were generated and linked together covering over the surface. After dried up, the as-formed surface showed superhydrophilic ability. Inspired by lotus only employing 2-tier structure and ordinary plant wax to maintain superhydrophobicity, paraffin wax, a low surface energy material, was used to modify the hierarchically structured nylon 6,6 surface. The resultant surface had water contact angle (CA) of 155.2+/-1.3 degrees and a low sliding angle. The whole process was carried on under ambient condition and only need a few minutes. Copyright 2010 Elsevier Inc. All rights reserved.

  1. Modeling and flow analysis of pure nylon polymer for injection molding process

    Nuruzzaman, D. M.; Kusaseh, N.; Basri, S.; Oumer, A. N.; Hamedon, Z.

    2016-02-01

    In the production of complex plastic parts, injection molding is one of the most popular industrial processes. This paper addresses the modeling and analysis of the flow process of the nylon (polyamide) polymer for injection molding process. To determine the best molding conditions, a series of simulations are carried out using Autodesk Moldflow Insight software and the processing parameters are adjusted. This mold filling commercial software simulates the cavity filling pattern along with temperature and pressure distributions in the mold cavity. In the modeling, during the plastics flow inside the mold cavity, different flow parameters such as fill time, pressure, temperature, shear rate and warp at different locations in the cavity are analyzed. Overall, this Moldflow is able to perform a relatively sophisticated analysis of the flow process of pure nylon. Thus the prediction of the filling of a mold cavity is very important and it becomes useful before a nylon plastic part to be manufactured.

  2. Effects of Kapton Sample Cell Windows on the Detection Limit of Smectite: Implications for CheMin on the Mars Science Laboratory Mission

    Achilles, C. N.; Ming, Douglas W.; Morris, R. V.; Blake, D. F.

    2012-01-01

    The CheMin instrument on the Mars Science Laboratory (MSL) rover Curiosity is an X-ray diffraction (XRD) and X-ray fluorescence (XRF) instrument capable of providing the mineralogical and chemical compositions of rocks and soils on the surface of Mars. CheMin uses a microfocus X-ray tube with a Co target, transmission geometry, and an energy-discriminating X-ray sensitive CCD to produce simultaneous 2-D XRD patterns and energy-dispersive X-ray histograms from powdered samples. CheMin has two different window materials used for sample cells -- Mylar and Kapton. Instrument details are provided elsewhere. Fe/Mg-smectite (e.g., nontronite) has been identified in Gale Crater, the MSL future landing site, by CRISM spectra. While large quantities of phyllosilicate minerals will be easily detected by CheMin, it is important to establish detection limits of such phases to understand capabilities and limitations of the instrument. A previous study indicated that the (001) peak of smectite at 15 Ang was detectable in a mixture of 1 wt.% smectite with olivine when Mylar is the window material for the sample cell. Complications arise when Kapton is the window material because Kapton itself also has a diffraction peak near 15 Ang (6.8 deg 2 Theta). This study presents results of mineral mixtures of smectite and olivine to determine smectite detection limits for Kapton sample cells. Because the intensity and position of the smectite (001) peak depends on the hydration state, we also analyzed mixtures with "hydrated" and "dehydrated"h smectite to examine the effects of hydration state on detection limits.

  3. Multiple relaxation processes in high-energy ion irradiated kapton-H polyimide: Thermally stimulated depolarization current study

    Garg, Maneesha; Quamara, J.K.

    2006-01-01

    High-energy ion irradiation effects on the thermally stimulated depolarization current (Tdc) behaviour of kapton-H samples (12.5 μm) irradiated with 50 MeV Li ion (fluence 5 x 10 4 , 10 5 and 5 x 10 5 ions/cm 2 ) have been investigated. The TSDC spectra of the irradiated samples reveal that the β-peak (appearing around 80-110 deg. C) associated with dipolar relaxation has been significantly affected owing to the demerization of carbonyl groups due to irradiation. The TSDC spectra also reveal a new relaxation process (termed as γ-relaxation) around 30 deg. C, due to increased water absorptivity in irradiated samples. The peak around 200 deg. C (α-peak) associated with space charge relaxation process also shows a behavioural change with ion irradiation. The peak not only shifts towards the higher temperature with increasing fluence but also show an increase in its activation energy (0.33-0.99 eV) with increasing polarizing field. The creation of new deep energy trap centers due to the formation of conjugated bonds after irradiation is responsible for this modification. The Cole-Cole distribution curves show the formation of new sub-polar group with different characteristic relaxation time

  4. Radiochemical study of isomerization of free butyl cations

    Sinotova, E.N.; Nefedov, V.D.; Skorokhodov, S.S.; Arkhipov, Yu.M.

    1987-01-01

    Ion-molecular reactions of free butyl cations, generated by nuclear chemical method, with carbon monoxide containing small quantities of ethanol vapors are studied. Carbon monoxide was used to fix instable butyl cations in the form of corresponding acyl ions. Ester of α-methyl-butyric acid appears to be the only product of free butyl cation interaction with carbon monoxide in the presence of ethanol vapors. That means, that up to the moment of butyl cation reaction with carbon monoxide, the primary butyl cations are almost completely isomerized into secondary in agreement with results of previous investigations. This allows one to study free butyl cation isomerization process according to ion-molecular reaction product isomeric composition

  5. Alternative fatty simulants and diffusion kinetics of nylon 12 food packaging

    Stoffers, N.H.; Dekker, M.; Linssen, J.P.H.; Stoermer, A.; Franz, R.

    2003-01-01

    The migration of laurolactam and cyclic di- and trimer of nylon 12 was assessed using three different films and five food simulants (olive oil, isooctane, 95% ethanol, 50% ethanol, water). Substitute test conditions for migration into olive oil according to European Union Directive EC/97/48 were

  6. Effect of gamma-irradiation on the plasticization of nylon 6 with benzyl alcohol

    Jamdagni, R.P.; Chaudhuri, N.K.

    1980-01-01

    The effect of γ-irradiation on the plasticization of nylon 6 monofilaments with benzyl alcohol by monitoring the glass transition temperature Tg after γ-irradiation has been studied. The method applied for determining the Tg is thermomechanical. The longitudinal deformation was determined with nylon 6 monofilaments immersed in benzyl alcohol, carrying a negligible weight to keep it taut. The temperature was varied in the range 3deg - 90deg C. Samples were prepared at different irradiation doses between 0 and 16 Mrad using a Cobalt-60 source. At each irradiation dose, a percentage extension vs temperature plot was made from the data obtained, and the Tg of the irradiated filament was determined from this plot. It was observed that the Tg started increasing very slowly upto 4 Mrad. The rate is appreciably faster after 8 Mrad. At 16 Mrad the Tg rises from its value in unirradiated nylon 6 monofilaments plasticized with benzyl alcohol, that is, the control, by about 13deg C. This upward shift of Tg is an antiplasticization effect and is accompanied with change of other mechanical properties, such as extensibility and tensile strength. The paper discusses the implication of these results in terms of previously known behaviour of scission and crosslinking due to γ-irradiation in nylon 6 and explores the possibility of application of the effect in processing. (author)

  7. Crystallization and melting behavior of multi-walled carbon nanotube-reinforced nylon-6 composites

    Phang, In Yee; Ma, Jianhua; Shen, Lu; Liu, Tianxi; Zhang, Wei-De

    2006-01-01

    The crystallization and melting behavior of neat nylon-6 (PA6) and multi-walled carbon nanotubes (MWNTs)/PA6 composites prepared by simple melt-compounding was comparatively studied. Differential scanning calorimetry (DSC) results show two crystallization exotherms (TCC, 1 and TCC, 2) for PA6/MWNTs

  8. Effect of cellulose fiber reinforcement on the temperature dependent mechanical performance of nylon 6

    Mehdi Tajvidi; Mokhtar Feizmand; Robert H. Falk; Colin Felton

    2009-01-01

    In order to quantify the effect of temperature on the mechanical properties of pure nylon 6 and its composite with cellulose fibers (containing 25 wt% cellulose fibers), the materials were sampled and tested at three representative temperatures of 256, 296, and 336 K. Flexural and tensile tests were performed and the reductions in mechanical properties were evaluated....

  9. Tensile Characterization of Injection-Molded Fuzzy Glass Fiber/Nylon Composite Material

    2016-05-01

    enhanced reinforcement (CER) in a nylon matrix. A majority of the masterbatch CER material research is focused on electromagnetic shielding applications...close as notionally shown in Fig. 1. These CER systems are subsequently enveloped in a polymer matrix to form a masterbatch CER pellet. In this

  10. An in vitro Evaluation on a Novel Root Canal Cleansing Method by Using Nylon Fibers

    Shiqian Gao

    2015-07-01

    Full Text Available Despite traditional metal-based dental files, such as NiTi being demonstrated effective in root cleaning, the tooth structure is always damaged. Thus, to fulfill the need for a minimally invasive tool for contemporary endodontics and dentistry, the use of polymer fibers might provide a good option, as it is soft, fabricable, and disposable. In this study, two types of nylon fibers with respective average diameters of 206.9 µm (fiber W and 156.4 µm (fiber B, respectively, were used as dental files, and mounted onto either a reciprocating or a low-speed rotary hand-piece. In vitro, simulated root canal models were colored red using nail varnish, and then cleaned by the fiber files mounted on the hand-pieces. Three parts of the simulated models, i.e., the apical third, the medium third, and the coronal third, were chosen to assess the cleaning the efficiency (CE of each specimen by calculating the ratio of the cross-sectional area changes, before and after cleansing, using micro-Computer Tomography (CT. A NiTi file with a low-speed hand-piece was used as a control. SEM was used to observe the nylon fiber surfaces before and after the cleansing. Micro-CT results showed that for both the nylon fibers, W and B, an average CE of 82.11% ± 9.68% for the medium third could be achieved, which is statistically higher (p < 0.01 than the coronal third and apical third. The cleansing efficiency was not affected by, the types of fibers, nor the hand-pieces according to student’s t-test. Most of the nylon fibers could withstand deformation after the cleansing. To conclude, nylon fiber files have demonstrated a certain cleansing efficiency in simulated root canals, and micro-CT is a promising method to assess CE.

  11. Suppression of gold nanoparticle agglomeration and its separation via nylon membranes

    Ayyavoo Jayalakshmi; In-Chul Kim; Young-Nam Kwon

    2017-01-01

    Use of ultraporous nylon membrane is one of the most widely employed techniques for removal of hard and soft nanoparticles in the semiconductor industry,and the accurate determination of membrane pore size is necessary in order to avoid manufacturing defects caused by contamination.The gold nanoparticle has several benefits for the evaluation of polymeric membranes;however,the nanoparticles agglomerate easily on the nylon membrane and make it difficult to evaluate the membrane precisely.The properties of 2-amino-2-hydroxymethyl-1,3-propanediol (ADP) ligand in gold nanoparticle solution were systematically investigated,and ADP was utilized for improved evaluation of the nylon membranes.Nylon membrane used in this study was prepared by phase inversion techniques.Ultrathin dense layer on top of the membrane surface and Darcy structures in the microporous membrane support were observed.The gold particle rejection was carried out at various pH values from 4 to 14 and higher rejection was observed at pH 4 and 8.The suppression of gold colloid agglomeration using ADP and monodispersity of gold colloids was also analyzed by confocal laser scanning microscopy (CLSM),transmission electron microscopy (TEM),and scanning electron microscopy (SEM).van der Waals interaction energy of the particles was reduced in the addition of ADP.The presence ofADP ligand in the gold solutions prevented the agglomeration of gold nanoparticles and reduced the adsorption of the particles on the nylon membrane surface,leading to precise evaluation of membrane pore sizes.

  12. Multifunctional ZnO/Nylon 6 nanofiber mats by an electrospinning-electrospraying hybrid process for use in protective applications

    Vitchuli, Narendiran; Shi Quan; McCord, Marian; Zhang Xiangwu [Fiber and Polymer Science Program, Department of Textile Engineering, Chemistry and Science, North Carolina State University, Raleigh, NC 27695-8301 (United States); Nowak, Joshua; Bourham, Mohamed [Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27695-7909 (United States); Kay, Kathryn [Department of Microbiology, North Carolina State University, Raleigh, NC 27695-7610 (United States); Caldwell, Jane M; Breidt, Frederick, E-mail: bourham@ncsu.edu, E-mail: mmccord@ncsu.edu, E-mail: xiangwu_zhang@ncsu.edu [Department of Food Science, North Carolina Agricultural Research Service, North Carolina State University, Raleigh, NC 27695-7624 (United States)

    2011-10-15

    ZnO/Nylon 6 nanofiber mats were prepared by an electrospinning-electrospraying hybrid process in which ZnO nanoparticles were dispersed on the surface of Nylon 6 nanofibers without becoming completely embedded. The prepared ZnO/Nylon 6 nanofiber mats were evaluated for their abilities to kill bacteria or inhibit their growth and to catalytically detoxify chemicals. Results showed that these ZnO/Nylon 6 nanofiber mats had excellent antibacterial efficiency (99.99%) against both the Gram-negative Escherichia coli and Gram-positive Bacillus cereus bacteria. In addition, they exhibited good detoxifying efficiency (95%) against paraoxon, a simulant of highly toxic chemicals. ZnO/Nylon 6 nanofiber mats were also deposited onto nylon/cotton woven fabrics and the nanofiber mats did not significantly affect the moisture vapor transmission rates and air permeability values of the fabrics. Therefore, ZnO/Nylon 6 nanofiber mats prepared by the electrospinning-electrospraying hybrid process are promising material candidates for protective applications.

  13. Multifunctional ZnO/Nylon 6 nanofiber mats by an electrospinning–electrospraying hybrid process for use in protective applications

    Narendiran Vitchuli, Quan Shi, Joshua Nowak, Kathryn Kay, Jane M Caldwell, Frederick Breidt, Mohamed Bourham, Marian McCord and Xiangwu Zhang

    2011-01-01

    Full Text Available ZnO/Nylon 6 nanofiber mats were prepared by an electrospinning–electrospraying hybrid process in which ZnO nanoparticles were dispersed on the surface of Nylon 6 nanofibers without becoming completely embedded. The prepared ZnO/Nylon 6 nanofiber mats were evaluated for their abilities to kill bacteria or inhibit their growth and to catalytically detoxify chemicals. Results showed that these ZnO/Nylon 6 nanofiber mats had excellent antibacterial efficiency (99.99% against both the Gram-negative Escherichia coli and Gram-positive Bacillus cereus bacteria. In addition, they exhibited good detoxifying efficiency (95% against paraoxon, a simulant of highly toxic chemicals. ZnO/Nylon 6 nanofiber mats were also deposited onto nylon/cotton woven fabrics and the nanofiber mats did not significantly affect the moisture vapor transmission rates and air permeability values of the fabrics. Therefore, ZnO/Nylon 6 nanofiber mats prepared by the electrospinning–electrospraying hybrid process are promising material candidates for protective applications.

  14. The Radiation Synthesis of Ultra-Fine Powdered Carboxylated Styrene-Butadiene Rubber (UFCSBR) and Property of Nylon 6/ UFCSBR Blends

    Xu, L.

    2006-01-01

    A serial of novel ultra-fine powdered carboxylated styrene-butadiene rubber (UFCSBR) were prepared by using radiation crosslinking and spray drying method. Thereafter, these powdered rubber particles were used as toughener of nylon 6.The radiation synthesis of ultra-fine powdered rubbers were studied, moreover, the mechanical and thermal property of nylon 6/UFCSBR blends were investigated. Finally, the toughening mechanism of nylon 6 modified with ultra-fine rubber particles was discussed. The UFCSBR could be dispersed well in nylon 6 as individual particles with a diameter of 150 nm by using melt blending. The Nylon 6/UFCSBR (80/20) blend possesses higher toughness and higher thermal stability than Nylon 6/POE-g-MAH (which is most often used elastomer in toughening nylon now). The deformation mechanism of nylon 6/UFCSBR blends includes shear deformation of nylon 6 and the formation of elongated rubber particles in matrix. In addition, the UFCSBR has good interfacial compatibility with nylon 6. Therefore, the nylon 6/UFCSBR blends with good mechanical performance could be prepared in this work

  15. Organic Semiconductors and Conductors with tert-Butyl Substituents

    Toshiki Higashino

    2012-08-01

    Full Text Available Tetrathiafulvalene (TTF, pentacene, and quarterthiophene with tert-butyl substituents are synthesized, and the crystal structures and the transistor properties are investigated. The tetracyanoquinodimethane (TCNQ complex of tert-butyl TTF constructs highly one-dimensional segregated columns with tetragonal crystal symmetry.

  16. An efficient and highly selective ortho-tert-butylation of p-cresol with methyl tert-butyl ether catalyzed by sulfonated ionic liquids

    Alamdari Reza Fareghi

    2014-01-01

    Full Text Available A novel series of sulfonic acid-functionalized ionic liquids (SFILs was found to act as efficient catalysts for ortho-tert-butylation of p-cresol with methyl tert-butyl ether (MTBE as the tert-butylating agent without an added solvent. The mono o-tert-butylated product was obtained in up to 80.4% isolated yield and 95.2% selectivity under such green conditions. No O-tert-butylated byproducts were formed.

  17. Experiments with all-Kapton insulation and axial prestress in 1.8 m-long SSC R ampersand D magnets

    Wanderer, P.; Anerella, M.; Cottingham, G.; Ganetis, G.; Garber, M.; Ghosh, A.; Greene, A.; Gupta, R.; Herrera, J.; Kahn, S.; Kelly, E.; Meade, A.; Morgan, G.; Muratore, J.; Prodell, A.; Rehak, M.; Rohrer, E.; Sampson, W.; Shutt, R.; Thompson, P.; Willen, E.; Goodzeit, C.; Radusewicz, P.

    1991-01-01

    Several 1.8 m-long magnets have been built to evaluate possible variations in the design of the SSC collider dipoles. Except for length and the parameters being tested, these models have the features of 40 mm aperture collider dipoles, which are based on a two-layer cosine theta coil. In these magnets, we have tested all-Kapton cable insulation and the effects of changes in the axial coil prestress. Construction details and test results for quenching, field harmonics, and coil loading are reported. 5 refs., 7 figs

  18. Utilization of Magnesium Hydroxide Produced by Magnesia Hydration as Fire Retardant for Nylon 6-6,6

    Rocha Sônia D.F.

    2001-01-01

    Full Text Available The present work investigates the use of magnesium hydroxide, produced by magnesia hydration, as a fire retardant in polymers. The hydration was carried out in an autoclave, at temperature of 130°C for 1 hour, and the product was further submitted to cominution in a jet mill. The solids were characterized with regard to their chemical composition, particle size distribution, surface area and morphology. The performance evaluation of the hydroxide as a flame retardant for a copolymer of nylon 6-6,6 was carried out according to the UL94 specifications for vertical burning tests. V-0 flammability rating at 1.6 mm (60% magnesium hydroxide-filled nylon composite and at 3.2 mm (40% magnesium hydroxide filled nylon composite were achieved. Mechanical properties were maintained at the desired values. These results indicate that the hydroxide obtained from magnesia hydration can be successfully employed as a fire retardant for nylon 6-6,6.

  19. Synthesis of Poly (Butyl Methacrylate/Butyl Acrylate) Highly Absorptive Resin Using Glow Discharge Electrolysis

    Li Yan; Yao Mengqi; Liao Ruirui; Yang Wu; Gao Jinzhang; Ren Jie

    2014-01-01

    A highly absorptive resin poly (butyl methacrylate (BMA)-co-butyl acrylate (BA)) was prepared by emulsion polymerization, which was initiated by glow discharge electrolysis plasma (GDEP). The effects of discharge voltage, discharge time, monomer ratio and the amounts of cross-linking agent were examined and discussed in detail. The chemical structure of the obtained resin was characterized by means of attenuated total reflectance Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. The optimal conditions were obtained as: discharge voltage was 600 V, discharge time was 8 min, the ratios of BMA:BA being 2:1 for chloroform and 3:1 for xylene, with 2% N, N'-methylenebis. Under optimal conditions, the oil absorbency was 70 g/g for chloroform and 46 g/g for xylene. Moreover, the absorptive dynamical behavior of the resulting resin was also investigated

  20. Primary aromatic amines (PAAs) in black nylon and other food-contact materials, 2004-2009

    Trier, Xenia Thorsager; Okholm, B.; Foverskov, Annie

    2010-01-01

    Primary aromatic amines (PAAs) were analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in migrates from 234 samples of food-contact materials, including black nylon (polyamide) kitchen utensils (n = 136), coloured plastics (28), and clear/printed multilayer film/laminates (41......), from retailers, importers, and food producers. A further 29 utensils in use were obtained from colleagues. Very high PAA migration was found from black nylon kitchen utensils to the food simulant 3% acetic acid: the 'non-detectable' limit (20 mu g aniline equivalents kg-1 food) was exceeded by up...... migration test conditions influenced the final test results. Long-term release of PAAs was fitted by diffusion modelling experiments and long-term release was also seen as expected from used utensils. Toxicologists consider these migration levels of the suspected carcinogenic PAAs as a problem of major...

  1. Evaluation of anaerobic degradation, biogas and digestate production of cereal silages using nylon-bags.

    Negri, Marco; Bacenetti, Jacopo; Fiala, Marco; Bocchi, Stefano

    2016-06-01

    In this study, the degradation efficiency and the biogas and digestate production during anaerobic digestion were evaluated for the cereal silages most used to feed biogas plants. To this purpose, silages of: maize from the whole plant, maize from the ear, triticale and wheat were digested, inside of nylon bags, in laboratory scale digesters, for 75days. Overall, the test involved 288 nylon bags. After 75days of digestion, the maize ear silage shows the highest degradation efficiency (about 98%) while wheat silage the lowest (about 83%). The biogas production ranges from 438 to 852Nm(3)/t of dry matter for wheat and ear maize silage, respectively. For all the cereal silages, the degradation as well as the biogas production are faster at the beginning of the digestion time. Digestate mass, expressed as percentage of the fresh matter, ranges from 38% to 84% for wheat and maize ear silage, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. A comparison of 2-octyl cyanoacrylate with nylon for wound closure of knee arthroscopy portals.

    Imbuldeniya, A M; Rashid, A; Murphy, J P

    2014-09-01

    To compare the cosmetic results, complications and patient satisfaction of 2-octyl cyanoacrylate (Dermabond, Ethicon Inc. Somerville, NJ, USA), a liquid bonding agent, with 3-0 nylon sutures (Ethilon, Ethicon Inc) skin closure in two groups of patients undergoing elective knee arthroscopy at 6 weeks. The retrospective clinical audit recruited patients undergoing knee surgery for the first time between October 2010 and August 2011. The patients were either treated with the liquid bonding agent or nylon sutures. The patients in the bonding agent group were allowed to shower as normal on postoperative day one, while patients in the suture group kept their wounds dry for 2 weeks. Between the two groups (40 patients per group) there was no difference in the cosmetic outcome (p=0.285), patient satisfaction (p=0.29), pain scores (p=0.44) or wound complication rate (pfinance was received for this study, nor any input from other sources.

  3. Characterization of nylon 6/poly(propylene oxide) polymeric mixture by combined NMR techniques

    Costa, Dilma Alves; Oliveira, Clara Marize F.; Tavares, Maria Ines B.

    1995-01-01

    Polymeric mixtures aim to improve physical or chemical properties of materials. This mixtures can be compatible or not. The compatibility between polymers determine changes of properties. This work has presented a detailed study where nylon 6 and poly(propylene oxide) mixture was analysed by 13 C NMR in the solid state, and NMR spectra were shown and explained. The molecular mobility as well as the compatibility have been observed and discussed

  4. Amorphous and crystalline phase interaction during the Brill transition in nylon 66

    2009-07-01

    Full Text Available A prominent α' process in specifically treated nylon 66 and microcomposite samples is identified by dynamic mechanical analysis and proposed to be an amorphous phase counterpart of the Brill transition identified by synchrotron wide-angle X-ray diffraction (WAXD. It is suggested that this α' process, which marks a critical free volume change and an onset of segmental chain movement in the amorphous phase, precedes and prompts the Brill transition in the crystalline phase.

  5. Screening nylon-3 polymers, a new class of cationic amphiphiles, for siRNA delivery.

    Nadithe, Venkatareddy; Liu, Runhui; Killinger, Bryan A; Movassaghian, Sara; Kim, Na Hyung; Moszczynska, Anna B; Masters, Kristyn S; Gellman, Samuel H; Merkel, Olivia M

    2015-02-02

    Amphiphilic nucleic acid carriers have attracted strong interest. Three groups of nylon-3 copolymers (poly-β-peptides) possessing different cationic/hydrophobic content were evaluated as siRNA delivery agents in this study. Their ability to condense siRNA was determined in SYBR Gold assays. Their cytotoxicity was tested by MTT assays, their efficiency of delivering Alexa Fluor-488-labeled siRNA intracellularly in the presence and absence of uptake inhibitors was assessed by flow cytometry, and their transfection efficacies were studied by luciferase knockdown in a cell line stably expressing luciferase (H1299/Luc). Endosomal release was determined by confocal laser scanning microscopy and colocalization with lysotracker. All polymers efficiently condensed siRNA at nitrogen-to-phosphate (N/P) ratios of 5 or lower, as reflected in hydrodynamic diameters smaller than that at N/P 1. Although several formulations had negative zeta potentials at N/P 1, G2C and G2D polyplexes yielded >80% uptake in H1299/Luc cells, as determined by flow cytometry. Luciferase knockdown (20-65%) was observed after transfection with polyplexes made of the high molecular weight polymers that were the most hydrophobic. The ability of nylon-3 polymers to deliver siRNA intracellularly even at negative zeta potential implies that they mediate transport across cell membranes based on their amphiphilicity. The cellular uptake route was determined to strongly depend on the presence of cholesterol in the cell membrane. These polymers are, therefore, very promising for siRNA delivery at reduced surface charge and toxicity. Our study identified nylon-3 formulations at low N/P ratios for effective gene knockdown, indicating that nylon-3 polymers are a new, promising type of gene delivery agent.

  6. Silver-Coated Nylon Dressing Plus Active DC Microcurrent for Healing of Autogenous Skin Donor Sites

    2013-08-01

    harvested; (c) bloodstream infection, burn-wound infection, hemodynamic instability requiring the use of pressors, or critical illness such as one...or nursing ; (h) sensitivity to silver or nylon; and (i) patient unable to provide written informed consent. Study Device The active microstimulator...the microcurrent stimulator. A research nurse monitored patient compli- ance by recording the amount of time the microcurrent stimulator was

  7. Screening Nylon-3 Polymers, a New Class of Cationic Amphiphiles, for siRNA Delivery

    2015-01-01

    Amphiphilic nucleic acid carriers have attracted strong interest. Three groups of nylon-3 copolymers (poly-β-peptides) possessing different cationic/hydrophobic content were evaluated as siRNA delivery agents in this study. Their ability to condense siRNA was determined in SYBR Gold assays. Their cytotoxicity was tested by MTT assays, their efficiency of delivering Alexa Fluor-488-labeled siRNA intracellularly in the presence and absence of uptake inhibitors was assessed by flow cytometry, and their transfection efficacies were studied by luciferase knockdown in a cell line stably expressing luciferase (H1299/Luc). Endosomal release was determined by confocal laser scanning microscopy and colocalization with lysotracker. All polymers efficiently condensed siRNA at nitrogen-to-phosphate (N/P) ratios of 5 or lower, as reflected in hydrodynamic diameters smaller than that at N/P 1. Although several formulations had negative zeta potentials at N/P 1, G2C and G2D polyplexes yielded >80% uptake in H1299/Luc cells, as determined by flow cytometry. Luciferase knockdown (20–65%) was observed after transfection with polyplexes made of the high molecular weight polymers that were the most hydrophobic. The ability of nylon-3 polymers to deliver siRNA intracellularly even at negative zeta potential implies that they mediate transport across cell membranes based on their amphiphilicity. The cellular uptake route was determined to strongly depend on the presence of cholesterol in the cell membrane. These polymers are, therefore, very promising for siRNA delivery at reduced surface charge and toxicity. Our study identified nylon-3 formulations at low N/P ratios for effective gene knockdown, indicating that nylon-3 polymers are a new, promising type of gene delivery agent. PMID:25437915

  8. Geotechnical properties of reinforced clayey soil using nylons carry’s bags by products

    Salim Nahla

    2018-01-01

    Full Text Available All structures built on soft soil may experience uncontrollable settlement and critical bearing capacity. This may not meet the design requirements for the geotechnical engineer. Soil stabilization is the change of these undesirable properties in order to meet the requirements. Traditional methods of stabilizing or through in-situ ground improvement such as compaction or replacement technique is usually costly. Now a safe and economic disposal of industrial wastes and development of economically feasible ground improvement techniques are the important challenges being faced by the engineering community. This work focuses on improving the soft soil brought from Baghdad by utilizing the local waste material for stabilization of soil, such as by using “Nylon carry bag’s by product” with the different percentage and corresponding to 1 %, 3% and 5% (the portion of stabilizer matters to soil net weight of dried soil. The results indicated that as Nylon’s fiber content increases, the liquid limit decreases while the plastic limit increases, so the plasticity index decreases. Furthermore, the maximum dry density decreases while, the optimum moisture content increases as the Nylon’s fiber percentage increases. The compression index (decreases as the Nylon’s fiber increases and provides a maximum of 43% reduction by adding 5% nylon waste material. In addition, the results indicated that, the undrained shear strength increases as the nylon fiber increases.

  9. Tissue reactions induced by nylon cable tie used to clamp ovarian pedicles

    Luiz Fernando Moraes Moreira

    2018-03-01

    Full Text Available The aim of this study was to evaluate the tissue reactions induced by nylon cable tie by using macroscopic and histological evaluations. Forty-five clinically healthy crossbreed female dogs, 31.11 ± 14.26 months old and with a body weight of 11.26 ± 4.7 kg, underwent ovariohysterectomy using a minimally invasive procedure. The dogs were randomly divided into three groups of 15 animals each and were evaluated preoperatively, and at 30 (G1, 60 (G2 and 90 days (G3 after surgery. The histological examination of the pedicles containing the nylon cable ties, collected from five animals in each group, showed a chronic inflammatory reaction with the presence of macrophages, giant cells and fibroplasia on the 30th postoperative day. Well-organized connective tissue and presence of lymphocytes and polymorphonuclear leukocytes were seen on the 60th postoperative day, and mature connective tissue and presence of macrophages and lymphocytes were seen at 90 days. Nylon cable ties induce an inflammatory reaction, which should be considered due to the risk of interference with surrounding structures.

  10. Modification of nylon-6 with semi-rigid poly (p-diphenyl oxide terephthalamide)

    Lin, M.F.; Wang, H.H.; Shu, Y.C.

    1994-01-01

    In this study, the flexible nylon-6 was reinforced by the semi-rigid aromatic polyamide, poly (p-diphenyl oxide terephthalamide) (POA), through physical polybending and chemical copolymerization using p-aminophenylacetic acid (P-APA) as a coupling agent. From the DSC measurements, it was shown that Tg of the polyblends was increased with the increase of POA content. The Tg and Tm of multiblock copolyamides were found to be higher than those of polyblends and triblock copolyamides. From the Rheovibron measurements, it was shown that the POA with nylon-6 poy-blends exhibited higher E' and Tg value than that of nylon-6, which increased with the increase of POA content. The Tg and E' values of multiblock copolyamides were higher than those of polyblends triblock copolyamides. Scanning electron microscopy revealed that the polyblends were a dispersed phase structure, although the multiblock copolyamides exhibited a homogeneous texture rather than an aggregated one. From the wide-angle x-ray diffraction pattern, the triblock copolyamides and polyblends had two diffraction peaks, i.e., 2 θ = 20.5 degrees and 24 degrees. However, the multiblock had only one at 2 θ = 20 degrees, which indicates that a different crystal structure of multiblock copolyamides. For the mechanical properties, it was found that the multiblock copolyamides had a more significant reinforcing effect than those of polyblends and triblock copolyamides. 21 refs., 11 figs., 5 tabs

  11. "The blood pressure and dermal sensitivity effects of Nylon hollow fiber releasing Glycerin Trinitrate in vivo "

    "Ostad SN

    2002-09-01

    Full Text Available In order to improve patient's compliance in taking glycerine trinitrate (GTN nylon hollow fiber which has been successfully used for release of chlorhexidine diacetate and levonorgestrel was employed to make nylon hollow fiber releasing GTN. Hollow nylon fibres of external diameter 0.63 mm, 75 mm long with an internal capacity of 16 μl, were filled with GTN (190 mg/ml in 70% ethanol (v/v or vehicle alone and the ends were heat-sealed. The fibers were then immersed in 10 ml of 0.9% (w/v saline in a separating funnel. The GTN release pattern from fiber, the effect of the product on blood pressure and its potential dermal toxicity were assessed. The release of GTN from the fibres was approximately 2.7 μg/min when the fibres contained 16 mg of drug. The results showed that the amount of GTN within the single fibre was enough to reduce blood pressure significantly, while it did not show significant dermal toxicity. It is concluded that GTN fiber, if used as monofilament, is not an alternative method for GTN delivery.

  12. The effect of cocoa (Theobroma cacao L on the basic color stability of thermoplastic nylon resin dentures

    Amiyatun Naini

    2011-11-01

    Full Text Available Nylon thermoplastic resin is material of choice for the making of flexible. This denture do not use wire retention, but has the physical properties of water absorption. In the oral cavity, it will always be in contact with food and beverages consumed. One of the foods that are consumed by the public is chocolate. This study aimed to determine the effect of cocoa (Theobroma cacao L on color stability of the thermoplastic nylon denture base. The study sample was thermoplastic nylon (valplast with a size of 10x10x2 mm soaked in the chocolate solution for 7 and 14 days. As the control, the sample soaked with distilled water. The color testing stability used was densitometer. There were significant differences between the control group (distilled water and the chocolate solution. This was due to dissolved components/tannin having a capillary flow diffusion into thermoplastic nylons that causing discoloration. The conclusion of this study, there was the effect of cocoa (Theobroma cacao L against the color stability of the nylon thermoplastic denture base. The longer time of immersion of nylon thermoplastic the greater the change in color.

  13. Low velocity impact properties of intra-ply hybrid composites based on basalt and nylon woven fabrics

    Dehkordi, Majid Tehrani; Nosraty, Hooshang; Shokrieh, Mahmood Mehrdad; Minak, Giangiacomo; Ghelli, Daniele

    2010-01-01

    In this paper, the low velocity impact behavior of homogenous and hybrid composite laminates reinforced by basalt-nylon intra-ply fabrics was experimentally investigated. Epoxy resin was used as matrix material. The purpose of using this hybrid composite is to combine the good mechanical properties of basalt fiber with the excellent impact resistant of nylon fiber. Five different types of woven fabrics were used as reinforcement with different volume percentages of nylon (0%, 25%, 33.3%, 50% and 100%). The effect of nylon/basalt fiber content on maximum force, maximum deflection, residual deflection, total absorbed energy, elastic energy, size and type of damage were studied at several low velocity impact nominal energy levels (16, 30 and 40 J). The results indicate that impact performance of these composites is significantly affected by the nylon/basalt fiber content. The visual inspection and ultrasonic C-scan of the impact damaged specimens reveals that content of nylon/basalt fiber controls the type and size of damage.

  14. Solubilization of meso-carbon microbeads by potassium- or dibutylzinc-promoted butylation and structural analysis of the butylated products; Mesocarbon microbeads no butyl ka ni yoru kayoka to erareta butyl kabutsu no kozo kaiseki

    Murata, S.; Zhang, Y.; Kidena, K.; Nomura, M. [Osaka University, Osaka (Japan). Faculty of Engineering

    1996-10-28

    Tetrahydrofuran (THF) solubility and structure of the butylated products of meso-carbon microbeads (MCMB) were studied experimentally. In experiment, MCMB-A and MCMB-B obtained from two kinds of coal-tar pitch were used as specimens. MCMBs were butylated by BZ method using dibutylzinc-butyl iodide and KT method using K-butyl iodide-THF, and the butylated products were successfully obtained. The butylated products were investigated through THF solubility test, {sup 13}C-NMR measurement and gel permeation chromatography (GPC) measurement. As the experimental result, a BZ method produced the butylated products at a yield of nearly 170%, while a KT method produced them at a yield of nearly 130%. The THF solubility was estimated to be 89-97%. As the study result of molecular weight distributions by GPC measurement of solvent solubles, the molecular weight of raw material MCMB was estimated to be 590-770 in terms of polystyrene. 6 refs., 2 figs., 1 tab.

  15. Automated batch emulsion copolymerization of styrene and butyl acrylate

    Mballa Mballa, M.A.; Schubert, U.S.; Heuts, J.P.A.; Herk, van A.M.

    2011-01-01

    This article describes a method for carrying out emulsion copolymerization using an automated synthesizer. For this purpose, batch emulsion copolymerizations of styrene and butyl acrylate were investigated. The optimization of the polymerization system required tuning the liquid transfer method,

  16. Solvent free lipase catalyzed synthesis of butyl caprylate

    MEERA T SOSE

    2017-11-10

    Nov 10, 2017 ... Department of Chemical Engineering, Institute of Chemical Technology, Matunga (E), ... study for the synthesis of butyl caprylate in presence of bio-catalyst. ..... −1 with Thermomyces lanuginosus lipase.26 The relation.

  17. Preparation and properties of banana fiber-reinforced composites based on high density polyethylene (HDPE)/Nylon-6 blends.

    Liu, H; Wu, Q; Zhang, Q

    2009-12-01

    Banana fiber (BaF)-filled composites based on high density polyethylene (HDPE)/Nylon-6 blends were prepared via a two-step extrusion method. Maleic anhydride grafted styrene/ethylene-butylene/styrene triblock polymer (SEBS-g-MA) and maleic anhydride grafted polyethylene (PE-g-MA) were used to enhance impact performance and interfacial bonding between BaF and the resins. Mechanical, crystallization/melting, thermal stability, water absorption, and morphological properties of the composites were investigated. In the presence of SEBS-g-MA, better strengths and moduli were found for HDPE/Nylon-6 based composites compared with corresponding HDPE based composites. At a fixed weight ratio of PE-g-MA to BaF, an increase of BaF loading up to 48.2 wt.% led to a continuous improvement in moduli and flexural strength of final composites, while impact toughness was lowered gradually. Predicted tensile modulus by the Hones-Paul model for three-dimensional random fiber orientation agreed well with experimental data at the BaF loading of 29.3 wt.%. However, the randomly-oriented fiber models underestimated experimental data at higher fiber levels. It was found that the presence of SEBS-g-MA had a positive influence on reinforcing effect of the Nylon-6 component in the composites. Thermal analysis results showed that fractionated crystallization of the Nylon-6 component in the composites was induced by the addition of both SEBS-g-MA and PE-g-MA. Thermal stability of both composite systems differed slightly, except an additional decomposition peak related to the minor Nylon-6 for the composites from the HDPE/Nylon-6 blends. In the presence of SEBS-g-MA, the addition of Nylon-6 and increased BaF loading level led to an increase in the water absorption value of the composites.

  18. Structures of butyl ions formed by electron impact ionization of isomeric butyl halides and alkanes

    Shold, D.M.; Ausloos, P.

    1978-01-01

    Using a pulsed ion cyclotron resonance (ICR) spectrometer, it is demonstrated that at pressures of about 10 -6 Torr and at observation times ranging from 10 -3 to 0.5 s, isobutane, neopentane, 2,2-dimethylbutane, isobutyl halides, and tert-butyl halides form C 4 H 9 + ions having the tertiary structure. In n-alkanes, 2-methylbutane, 3-methylpentane, n-butyl halides, and sec-butyl halides, both sec-C 4 H 9 + and t-C 4 H 9 + ions are observed, the sec-C 4 H 9 + ions surviving without rearrangement for at least 0.1 s. However, in the case of the halides, a collision-induced isomerization of the sec-C 4 H 9 + to the t-C 4 H 9 + ions occurs. The efficiency of this process increases with the basicity of the alkyl halide. Radiolysis experiments carried out at atmospheric pressures indicate, in agreement with ICR and solution experiments, that at times as short as 10 -10 s the majority of the i-C 4 H 9 + ions from isobutyl bromide rearrange to the t-C 4 H 9 + structure. On the other hand, in the radiolysis of both n-hexane and 3-methylpentane, the abundance of t-C 4 H 9 + relative to sec-C 4 H 9 + is substantially smaller than that observed in the ICR experiments, and decreases with decreasing collision interval. It is suggested that about 90% of the i-C 4 H 9 + can rearrange to t-C 4 H 9 + by simple 1,2-hydride shift without involving secondary or protonated methylcyclopropane structures as intermediates. 4 figures, 2 tables

  19. Protesa Maksilofasial Thermoplastic Nylon (Valplast dengan Hollow Bulb (Klas III Aramany palate schisis hereditary

    A. Azhindra

    2012-06-01

    Full Text Available Latar Belakang: pada penderita palato schisis (celah langit-langityang disebkan hereditary atau bawaan lahir terlihat defect yang menyebabkan gangguan bicara (sengau, penelanan, pengunyahan, estetik, dan psikologis. Untuk dapat mencapai fungsi bicara, fungsi mengunyah dan fungsi estetika diperlukan protesa untuk menutup celah tersebut. Tujuan: untuk meninformasikan cara rehabilitas defect atau cacat pada wajah dengan protesa maksilofasial thermoplastic nylon dengan hollow buib yang berguna untuk mengembalikan fungsi bicara, penelanan, pengunyahan, estetik dan psikologis penderita. Kasus dan penanganan: pasien pria berusia 46 tahun dating ke RSGM Prof. Soedomo atas rujukan dari poli RS. Dr. Sardjito. Saat datang pasien terganggu berbicara, menguyah dan menelan disebkan adanya celah langit-langit terbuka dan merupakan kelainan bawaan. Pasien kehilangan banyak gigi terutama pada gigi posterior pada rahang atas dan ingin dibuatkan gigi tiruan. Obturator ini dibuat segera dengan mempertimbangkan penutupan celah langit-langit, menggunakan bahan yang lebih ringan (menggunakan hoolow bulb agar keluhan pasien dapat diatasi didesain alat yang mempunyai retensi maksimal dan mengembalikan pengunyahan, fungsi bicara, penelanan, estetis dan psikologis sehingga pasien akan akan mempunyai bentuk wajah yang mendekati normal. Hollow bulb adalah rongga yang dibuat pada protesa maksilofasial untuk menutup rongga mulut, rongga hidung dan defect. Pada waktu insersi diperiksa retensi, stabilisasi, oklusi, estetik dan pengucapan. Kontrol dilakukan 1 minggu dan 1 bulan setelah pemakaian. Hasil pemeriksaan dan evaluasi setelah 1 minggu dan 1 bulan setelah pemakaian protesa maksilofasial hollow bulb didapatkan hasil dengan retensi, stabilisasi, olusi dan pengucapan lebih baik. Kesimpulan: setelah menggunakan protesa maksilofasial thermoplastic nylon dengan hollow buib pada penderita palato scisis, pasien dapat berbicara dan mengunyah dengan normal. Protesa maksilofasial

  20. Crystallisation and structural studies of monodisperse nylon oligomers and related polymers

    Sikorski, P.T.

    2001-11-01

    Using electron and X-ray diffraction data, together with computerised molecular modeling, the structures of monodisperse nylon oligomers and related polymers have been investigated. Structural changes on heating were also studied. The molecules were crystallised from solution and their morphologies examined using optical and transmission electron microscopy. Lath-like lamellar crystals of the polyester poly-β-propiolactone were crystallised isothermally. The interpretation of the diffraction data with the use of molecular modeling led to the discovery of the new crystalline structure, the γ-structure. In the γ-structure, the polyester chain is in an all-trans conformation and the structure consists of a two-chain, basal-faced, orthorhombic unit cell. The setting angles, with respect to the a axis, are ± 51.5 deg for the corner and centre chains, respectively. The lamellae are 5 nm in thickness and the chains run orthogonal to the lamellar surface. The general fold direction is along the a-axis (long axis of the crystal) and the chain folds successively in the [110] and [11-bar0] directions. Three different nylon 4 6 oligomers were crystallised from solution using a range of crystallisation methods. The 4- and 8-amide molecules were found to form three-dimensional crystals, in which the crystal thickness was much greater than the molecular length. The structure was found to be different from the nylon 4 6 polymer reported previously. It was found that the type of hydrogen-bonded sheet formed by these molecules can influence the way in which these sheets stack to form crystals. In addition, a study of the 9-amide molecule showed that a particular type of hydrogen-bonded sheet, a-sheet, is preferred for nylon 4 6. This discovery suggests that an amide unit is found in the fold in the chain-folded nylon 4 6 polymer crystals, to allow the a-sheets to be formed. It is not a consequence of a need to form a stress-free fold. In the regular adjacent re-entry chain

  1. Peptide-Like Nylon-3 Polymers with Activity against Phylogenetically Diverse, Intrinsically Drug-Resistant Pathogenic Fungi.

    Rank, Leslie A; Walsh, Naomi M; Lim, Fang Yun; Gellman, Samuel H; Keller, Nancy P; Hull, Christina M

    2018-01-01

    Understanding the dimensions of fungal diversity has major implications for the control of diseases in humans, plants, and animals and in the overall health of ecosystems on the planet. One ancient evolutionary strategy organisms use to manage interactions with microbes, including fungi, is to produce host defense peptides (HDPs). HDPs and their synthetic analogs have been subjects of interest as potential therapeutic agents. Due to increases in fungal disease worldwide, there is great interest in developing novel antifungal agents. Here we describe activity of polymeric HDP analogs against fungi from 18 pathogenic genera composed of 41 species and 72 isolates. The synthetic polymers are members of the nylon-3 family (poly-β-amino acid materials). Three different nylon-3 polymers show high efficacy against surprisingly diverse fungi. Across the phylogenetic spectrum (with the exception of Aspergillus species), yeasts, dermatophytes, dimorphic fungi, and molds were all sensitive to the effects of these polymers. Even fungi intrinsically resistant to current antifungal drugs, such as the causative agents of mucormycosis ( Rhizopus spp.) and those with acquired resistance to azole drugs, showed nylon-3 polymer sensitivity. In addition, the emerging pathogens Pseudogymnoascus destructans (cause of white nose syndrome in bats) and Candida auris (cause of nosocomial infections of humans) were also sensitive. The three nylon-3 polymers exhibited relatively low toxicity toward mammalian cells. These findings raise the possibility that nylon-3 polymers could be useful against fungi for which there are only limited and/or no antifungal agents available at present. IMPORTANCE Fungi reside in all ecosystems on earth and impart both positive and negative effects on human, plant, and animal health. Fungal disease is on the rise worldwide, and there is a critical need for more effective and less toxic antifungal agents. Nylon-3 polymers are short, sequence random, poly

  2. Quantitative approach to relate dielectric constant studies with TSDC studies of 50 MeV Si ion irradiated kapton-H polymide

    Quamara, J.K.; Garg, Maneesha; Sridharbabu, Y.; Prabhavathi, T.

    2003-01-01

    Temperature and frequency dependent dielectric behaviour has been investigated for pristine and swift heavy ion irradiated (Si ion, 50 MeV energy) kapton-H polyimide in the temperature range of 30 to 250 deg C at frequencies 120 Hz, 1 kHz, 10 kHz and 100 kHz respectively. The dielectric relaxation behaviour of the same samples was also studied using thermally stimulated discharge current (TSDC) technique. A quantitative approach is developed using a well-known Clausius Mossotti equation to relate the TSDC findings to the dielectric constant studies. An overall increase in the dielectric constant of the irradiated samples are also in conformity to the TSDC findings. (author)

  3. AZ-2000-IECW and StaMet Black Kapton Options for Solar Probe Plus MAG Sensor MLI Kevlar/Polyimide Shells

    Choi, Michael K.

    2017-01-01

    AZ-2000-IECW white paint and StaMet black Kapton have been evaluated for the Kevlar/polyimide shells that enclose the Solar Probe Plus Magnetometer (MAG) sensors and multilayer insulation. Flight qualification testing on AZ-2000-IECW painted Kevlar/polyimide laminate was completed at Goddard Space Flight Center. This paint potentially meets all the requirements. However, it has no flight heritage. StaMet is hotter in the sun, and is specular. The results of the MAG thermal balance test show StaMet meets the thermal requirement and heater power budget. The mission prefers to fly StaMet after evaluating the risks of AZ-2000-IECW flaking and glint from StaMet to the Star Trackers.

  4. Graft copolymerization of vinyl monomers onto nylon 6 fibers by γ-ray pre-irradiation in air

    Iwasaki, Tatsuo; Ueda, Yoshitsugu

    1992-01-01

    Vinyl acetate, methyl methacrylate, alkyl acrylates, acrylonitrile, and acrylamide, were grafted onto nylon 6 fibers by the γ-ray pre-irradiation technique, and the effects of grafting on the microstructure and the mechanical properties of the graft copolymers were investigated. According to the analysis by wide-angle X-ray diffraction, the degree of crystallization decreased by increasing the percent graft of poly(vinyl acetate) in the grafted nylon 6 films. The mechanical parameters, such as the Young's modulus and the tensile strength at break, increased with increasing percent graft up to 50%. When percent grafting was smaller than 50%, rather homogeneous amorphous materials were obtained with vinyl acetate, while heterogeneous ones were obtained with other vinyl monomers. A poly(vinyl alcohol) grafted nylon 6 was obtained effectively by saponification of poly(vinyl acetate) grafted nylon 6, the former showing higher mechanical properties than the latter. Similar behavior was observed after saponification of the poly(methyl acrylate) grafted nylon 6. (author)

  5. Photocatalytic and antibacterial properties of a TiO2/nylon-6 electrospun nanocomposite mat containing silver nanoparticles

    Pant, Hem Raj; Pandeya, Dipendra Raj; Nam, Ki Taek; Baek, Woo-il; Hong, Seong Tshool; Kim, Hak Yong

    2011-01-01

    Silver-impregnated TiO 2 /nylon-6 nanocomposite mats exhibit excellent characteristics as a filter media with good photocatalytic and antibacterial properties and durability for repeated use. Silver nanoparticles (NPs) were successfully embedded in electrospun TiO 2 /nylon-6 composite nanofibers through the photocatalytic reduction of silver nitrate solution under UV-light irradiation. TiO 2 NPs present in nylon-6 solution were able to cause the formation of a high aspect ratio spider-wave-like structure during electrospinning and facilitated the UV photoreduction of AgNO 3 to Ag. TEM images, UV-visible and XRD spectra confirmed that monodisperse Ag NPs (approximately 4 nm in size) were deposited selectively upon the TiO 2 NPs of the prepared nanocomposite mat. The antibacterial property of a TiO 2 /nylon-6 composite mat loaded with Ag NPs was tested against Escherichia coli, and the photoactive property was tested against methylene blue. All of the results showed that TiO 2 /nylon-6 nanocomposite mats loaded with Ag NPs are more effective than composite mats without Ag NPs. The prepared material has potential as an economically friendly photocatalyst and water filter media because it allows the NPs to be reused.

  6. Dispersion of nano-silica in monomer casting nylon6 and its effect on the structure and properties of composites

    2010-07-01

    Full Text Available To promote dispersion of nano-silica in monomer casting nylon6 (MC nylon6, nano-silica was dispersed in melted caprolactam with the assistance of ultrasound, anionic polymerization was then initiated to form silica/MC nylon6 in-situ nanocomposites. It was found that hydrogen bonds were formed between nano-silica and caprolactam, in the meantime, ultrasound helped to break the nanoparticles aggregations into smaller ones or even mono-dispersing particles. Therefore, the agglomerated nanoparticles were pulled apart and stabilized by caprolactam. Additionally, the rapid anionic polymerization of caprolactam also contributed to the avoidance of re-agglomeration and deposition of nanoparticles during the polymerization process, leading to the uniform distribution of nanoparticles in the polymer matrix. Mechanical tests indicated that the silica/MC nylon6 in-situ nanocomposites prepared according to the above strategy were simultaneously toughened, strengthened and stiffened. Thermogravimetric analysis (TGA results showed that thermal stability of nanocomposites was notably improved compared to neat MC nylon6.

  7. Photocatalytic and antibacterial properties of a TiO{sub 2}/nylon-6 electrospun nanocomposite mat containing silver nanoparticles

    Pant, Hem Raj [Department of Bionanosystem Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Department of Engineering Science and Humanities, Institute of Engineering, Pulchowk Campus, Tribhuvan University, Kathmandu (Nepal); Pandeya, Dipendra Raj [Department of Microbiology and Immunology, Institute for Medical Science, Chonbuk National University, Jeonju, 561-756 (Korea, Republic of); Nam, Ki Taek; Baek, Woo-il [Department of Textile Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Hong, Seong Tshool [Department of Microbiology and Immunology, Institute for Medical Science, Chonbuk National University, Jeonju, 561-756 (Korea, Republic of); Kim, Hak Yong, E-mail: khy@jbnu.ac.kr [Department of Textile Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

    2011-05-15

    Silver-impregnated TiO{sub 2}/nylon-6 nanocomposite mats exhibit excellent characteristics as a filter media with good photocatalytic and antibacterial properties and durability for repeated use. Silver nanoparticles (NPs) were successfully embedded in electrospun TiO{sub 2}/nylon-6 composite nanofibers through the photocatalytic reduction of silver nitrate solution under UV-light irradiation. TiO{sub 2} NPs present in nylon-6 solution were able to cause the formation of a high aspect ratio spider-wave-like structure during electrospinning and facilitated the UV photoreduction of AgNO{sub 3} to Ag. TEM images, UV-visible and XRD spectra confirmed that monodisperse Ag NPs (approximately 4 nm in size) were deposited selectively upon the TiO{sub 2} NPs of the prepared nanocomposite mat. The antibacterial property of a TiO{sub 2}/nylon-6 composite mat loaded with Ag NPs was tested against Escherichia coli, and the photoactive property was tested against methylene blue. All of the results showed that TiO{sub 2}/nylon-6 nanocomposite mats loaded with Ag NPs are more effective than composite mats without Ag NPs. The prepared material has potential as an economically friendly photocatalyst and water filter media because it allows the NPs to be reused.

  8. MicroArray Facility: a laboratory information management system with extended support for Nylon based technologies

    Beaudoing Emmanuel

    2006-09-01

    Full Text Available Abstract Background High throughput gene expression profiling (GEP is becoming a routine technique in life science laboratories. With experimental designs that repeatedly span thousands of genes and hundreds of samples, relying on a dedicated database infrastructure is no longer an option. GEP technology is a fast moving target, with new approaches constantly broadening the field diversity. This technology heterogeneity, compounded by the informatics complexity of GEP databases, means that software developments have so far focused on mainstream techniques, leaving less typical yet established techniques such as Nylon microarrays at best partially supported. Results MAF (MicroArray Facility is the laboratory database system we have developed for managing the design, production and hybridization of spotted microarrays. Although it can support the widely used glass microarrays and oligo-chips, MAF was designed with the specific idiosyncrasies of Nylon based microarrays in mind. Notably single channel radioactive probes, microarray stripping and reuse, vector control hybridizations and spike-in controls are all natively supported by the software suite. MicroArray Facility is MIAME supportive and dynamically provides feedback on missing annotations to help users estimate effective MIAME compliance. Genomic data such as clone identifiers and gene symbols are also directly annotated by MAF software using standard public resources. The MAGE-ML data format is implemented for full data export. Journalized database operations (audit tracking, data anonymization, material traceability and user/project level confidentiality policies are also managed by MAF. Conclusion MicroArray Facility is a complete data management system for microarray producers and end-users. Particular care has been devoted to adequately model Nylon based microarrays. The MAF system, developed and implemented in both private and academic environments, has proved a robust solution for

  9. Comparison of synthetic glues and 10-0 nylon in rabbit lamellar keratoplasty.

    Cho, Soon Young; Kim, Man Soo; Oh, Su Ja; Chung, Sung Kun

    2013-09-01

    To evaluate changes in mean keratometry and to compare wound repair with corneal lamellar grafts in rabbit eyes using human synthetic tissue adhesives and 10-0 nylon. Corneal grafts were made using a 6.0-mm-diameter trephine and blades in the eyes of 15 New Zealand white rabbits. Human fibrin tissue adhesive (Tisseel) was used in group 1, human fibrin tissue adhesive (Beriplast P) was used in group 2, polyethylene glycol adhesive (Coseal) was used in group 3, and 8 bite sutures with 10-0 nylon were used in group 4 (control) for lamellar keratoplasty. Four bite sutures were made with 10-0 nylon in groups 1, 2, and 3. Slit-lamp microscopy and keratometry were performed at 3 days and 1, 2, and 4 weeks after the surgery. Histopathologic and electromicroscopic examinations were performed 4 weeks after the surgery. No inflammation or corneal toxicity was seen in groups 1 and 2. Histologically, a few inflammatory cells were seen in groups 3 and 4. Groups 1, 2, and 3 showed no statistically significant changes in mean keratometry at 4 weeks postoperatively compared with preoperative mean keratometry (Wilcoxon signed-rank test, P = 0.178, 0.208, and 0.889, respectively). The control group showed significant changes in mean keratometry at 4 weeks postoperatively (Wilcoxon signed-rank test, P = 0.018). Human fibrin tissue adhesives were well tolerated in rabbit eyes, with no apparent corneal toxicity. Polyethylene glycol adhesive showed more inflammation and insufficient wound repair compared with human fibrin tissue adhesives. Therefore, human fibrin tissue adhesives can be used as an alternative to sutures in lamellar keratoplasty.

  10. Flock worker's lung: chronic interstitial lung disease in the nylon flocking industry.

    Kern, D G; Crausman, R S; Durand, K T; Nayer, A; Kuhn, C

    1998-08-15

    Two young men working at a nylon flocking plant in Rhode Island developed interstitial lung disease of unknown cause. Similar clusters at the same company's Canadian plant were reported previously. To define the extent, clinicopathologic features, and potential causes of the apparent disease outbreak. Case-finding survey and retrospective cohort study. Academic occupational medicine program. All workers employed at the Rhode Island plant on or after 15 June 1990. Symptomatic employees had chest radiography, pulmonary function tests, high-resolution computed tomography, and serologic testing. Those with unexplained radiographic or pulmonary function abnormalities underwent bronchoalveolar lavage, lung biopsy, or both. The case definition of "flock worker's lung" required histologic evidence of interstitial lung disease (or lavage evidence of lung inflammation) not explained by another condition. Eight cases of flock worker's lung were identified at the Rhode Island plant. Three cases were characterized by a high proportion of eosinophils (25% to 40%) in lavage fluid. Six of the seven patients who had biopsy had histologic findings of nonspecific interstitial pneumonia, and the seventh had bronchiolitis obliterans organizing pneumonia. All seven of these patients had peribronchovascular interstitial lymphoid nodules, usually with germinal centers, and most had lymphocytic bronchiolitis and interstitial fibrosis. All improved after leaving work. Review of the Canadian tissue specimens showed many similar histologic findings. Among the 165-member study cohort, a 48-fold or greater increase was seen in the sex-adjusted incidence rate of all interstitial lung disease. Work in the nylon flocking industry poses substantial risk for a previously unrecognized occupational interstitial lung disease. Nylon fiber is the suspected cause of this condition.

  11. A novel approach for application of nylon membranes in the biosensing domain

    Farahmand, Elham; Ibrahim, Fatimah; Hosseini, Samira; Rothan, Hussin A.; Yusof, Rohana; Koole, Leo H.; Djordjevic, Ivan

    2015-01-01

    Graphical abstract: - Highlights: • Polymer coated nylon membranes as bioreceptor surfaces. • Carboxylated porous surface for protein immobilization. • High level of biosensing performance for dengue virus detection. - Abstract: In this paper we report the polymer-coated microporous nylon membranes and their application as platforms for protein immobilization and subsequent detection of the dengue virus (DV) in blood serum. Protein recognition experiments were performed with enzyme-linked immunosorbent assay (ELISA). The polymers used for coatings were synthesized by free-radical polymerization reaction between methyl methacrylate (MMA) and methacrylic acid (MAA) in different concentrations. The MAA monomer has carefully been chosen to generate polymers with pendant carboxyl (–COOH) groups, which also exist on polymer surfaces. A high degree of control over surface-exposed –COOH groups has been achieved through variation of monomers concentration in polymerization reaction. The general aspect of this work relies on the dengue antibody (Ab) immobilization on surface –COOH groups via physical attachment or covalent immobilization. Prior to Ab immobilization and ELISA experiment, polymer-coated nylon samples were analyzed in detail for their physical properties by atomic force microscopy (AFM), scanning electron microscopy (SEM), and water-in-air contact angle (WCA) measurements. Membranes were further analyzed by Fourier transform infrared spectroscopy (FTIR) in order to establish the relationship between wettability, porosity, and surface roughness with chemical composition and concentration of –COOH groups on the coating's surface. Optimized coatings have shown high sensitivity towards dengue Ab molecules, revealing fundamental aspect of polymer–protein interfaces as a function of surface –COOH groups’ concentration.

  12. A novel approach for application of nylon membranes in the biosensing domain

    Farahmand, Elham; Ibrahim, Fatimah; Hosseini, Samira [Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603 (Malaysia); Center for Innovation in Medical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603 (Malaysia); Rothan, Hussin A.; Yusof, Rohana [Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603 (Malaysia); Koole, Leo H. [Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603 (Malaysia); Center for Innovation in Medical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603 (Malaysia); Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht (Netherlands); Djordjevic, Ivan, E-mail: ivandjordjevich@hotmail.com [Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603 (Malaysia); Center for Innovation in Medical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603 (Malaysia)

    2015-10-30

    Graphical abstract: - Highlights: • Polymer coated nylon membranes as bioreceptor surfaces. • Carboxylated porous surface for protein immobilization. • High level of biosensing performance for dengue virus detection. - Abstract: In this paper we report the polymer-coated microporous nylon membranes and their application as platforms for protein immobilization and subsequent detection of the dengue virus (DV) in blood serum. Protein recognition experiments were performed with enzyme-linked immunosorbent assay (ELISA). The polymers used for coatings were synthesized by free-radical polymerization reaction between methyl methacrylate (MMA) and methacrylic acid (MAA) in different concentrations. The MAA monomer has carefully been chosen to generate polymers with pendant carboxyl (–COOH) groups, which also exist on polymer surfaces. A high degree of control over surface-exposed –COOH groups has been achieved through variation of monomers concentration in polymerization reaction. The general aspect of this work relies on the dengue antibody (Ab) immobilization on surface –COOH groups via physical attachment or covalent immobilization. Prior to Ab immobilization and ELISA experiment, polymer-coated nylon samples were analyzed in detail for their physical properties by atomic force microscopy (AFM), scanning electron microscopy (SEM), and water-in-air contact angle (WCA) measurements. Membranes were further analyzed by Fourier transform infrared spectroscopy (FTIR) in order to establish the relationship between wettability, porosity, and surface roughness with chemical composition and concentration of –COOH groups on the coating's surface. Optimized coatings have shown high sensitivity towards dengue Ab molecules, revealing fundamental aspect of polymer–protein interfaces as a function of surface –COOH groups’ concentration.

  13. Analysis of primary aromatic amines (PAA) in black nylon kitchenware 2014

    Trier, Xenia; Granby, Kit

    is 0,01 mg of substance per kg of food or food simulant. The detection limit applies to the sum of primary aromatic amines released’ Since July 1st 2011, an additional EU regulation has come into place, which states that each consignment of polyamide (nylon) kitchen utensils from China and Hong Kong......% acetic acid as food simulant at an exposure temperature of 100°C and time from ½-4 hours, depending on the foreseeable use of the utensil. The samples were collected by the Norwegian Food Safety Authority at importers and retail shops. Of the 20 PAAs analysed. four PAAs were detected, being aniline (ANL...

  14. Comparison of Three Methods for Generating Superhydrophobic, Superoleophobic Nylon Nonwoven Surfaces (Postprint)

    2011-04-01

    film and onto a 100 g/ m2 nylon nonwoven substrate was carried out in a cylindri- cal , inductively coupled plasma reactor (10 cm diameter and 2700 cm3...the Nonwoven Institute (NI) for sharing hydro- entangled nonwoven fabric with us. References 1. Barthlott W, Neinhuis C (1997) Planta 202:1 2. Wu X...Faraday Soc 40:546 8. Lee H (2009) J Mater Sci 44:4645. doi:10.1007/s10853-009- 3711-5 9. Hoefnagels H, Wu D, de With G, Ming W (2007) Langmuir 23

  15. FAST TRACK COMMUNICATION: Deposition of amino-rich thin films by RF magnetron sputtering of nylon

    Kylián, O.; Hanuš, J.; Choukourov, A.; Kousal, J.; Slavínská, D.; Biederman, H.

    2009-07-01

    RF magnetron sputtering of a nylon target in different gas mixtures was studied in order to evaluate the capability of this process to deposit amino-rich coatings needed in a wide range of biomedical applications. It has been demonstrated that both the deposition rate of the coatings and the surface density of primary amino groups are strongly linked with working gas mixture composition. From this point of view, a sufficiently high deposition rate as well as the highest amine efficiency reaching a NH2/C value of 18% was observed in the N2/H2 discharge, which leads to the surface exhibiting a high rate of protein adsorption.

  16. Chronic interstitial lung disease in nylon flocking industry workers--Rhode Island, 1992-1996.

    1997-09-26

    Interstitial lung disease (ILD) occurs infrequently; some cases are attributed to sarcoidosis, pulmonary hemorrhage syndromes, connective tissue diseases, hypersensitivity pneumonitis, drugs, radiation, and mineral dusts (e.g., silica or asbestos). However, most cases of ILD are of uncertain classification or etiology. This report describes preliminary findings of the investigation in Rhode Island of an outbreak of ILD among workers involved in the manufacture of finely cut nylon (flock) and flocked fabric (used for upholstery, clothing, and automobiles); the findings provide evidence of a newly recognized occupational illness.

  17. Acute inflammatory reaction in rats after intratracheal instillation of material collected from a nylon flocking plant.

    Porter, D W; Castranova, V; Robinson, V A; Hubbs, A F; Mercer, R R; Scabilloni, J; Goldsmith, T; Schwegler-Berry, D; Battelli, L; Washko, R; Burkhart, J; Piacitelli, C; Whitmer, M; Jones, W

    1999-05-14

    Several cases of interstitial lung disease have been diagnosed among workers at a nylon flock plant, but the etiologic agent for the disease outbreak was unknown. The results of a medical survey and industrial hygiene study indicated that the dust present in the plant may be responsible. Thus, airborne dust collected at the plant was examined for its inflammatory potential in rat lungs. The endpoints measured were: (1) breathing rates, (2) differential cell counts of bronchoalveolar lavage cells, (3) alveolar macrophage (AM) chemiluminescence, (4) albumin concentration and matrix metalloprotease activities in the acellular fluid from the initial bronchoalveolar lavage, and (5) pulmonary histopathology. In the first study, rats received a single dose of the airborne dust sample (10 mg/kg body weight) by intratracheal (IT) instillation. At 1 d post-IT, all inflammatory endpoints were significantly increased versus controls, but by 29 d post-IT they did not differ significantly from controls. Histopathology demonstrated mild to moderate, multifocal, suppurative pneumonia, usually centered around bronchioles, at 1 d post-IT. At 29 d post-IT, pulmonary inflammation was minimal to mild and characterized by alveolar histocytosis usually restricted to the immediate area of retained bire-fringent fibers. In subsequent experiments, airborne dust was extracted with water and the dust (washed airborne dust) and water extract (soluble fraction) were separated by centrifugation for further study. Nylon tow dust was prepared in the laboratory by milling uncut nylon strands (called tow) that had not been treated with the finish or dyes that are commonly used in the flock plants. Rats were administered a single dose of a dust sample (10 mg/kg body weight) or the soluble fraction (1.3 ml/kg body weight) by IT administration and the same endpoints were measured at 1 d post-IT. The dust samples caused significant increases in all of the inflammatory endpoints; however, the soluble

  18. Sound Insulation Property Study on Nylon 66 Scrim Reinforced PVF Laminated Membranes and their Composite Sound Proof Structure

    Chen, Lihe; Chen, Zhaofeng; Zhang, Xinyang; Wang, Weiwei

    2018-01-01

    In this paper, we investigated the sound insulation property of nylon 66 scrim reinforced PVF laminated membranes and their corresponding composite structures with glass fiber felt and carbon fiber board. Sound transmission loss (STL) was measured by standing wave tube method. The results show that, with the decrease of nylon 66 gridlines spacing, STL of nylon 66 scrim reinforced PVF laminated membranes was improved. The sound insulation performance of laminated membranes with gridlines spacing of 3mm is the best, whose STL was up to 10dB at 6.3 kHz. Besides, STL was improved effectively as air layers were embedded into the composite sound proof construction consist of laminated membrane, glass fiber felt and carbon fiber board.

  19. Development of nylon-based artificial muscles for the usage in robotic prosthetic limb

    Atikah, Nurul Anis; Weng, Leong Yeng; Anuar, Adzly; Fat, Chau Chien; Abidin, Izham Zainal; Sahari, Khairul Salleh Mohamed

    2017-09-01

    This paper describes the development of nylon-based artificial muscles that is intended to be used in prosthetic limb for young amputees. Prosthetic limbs are very expensive and this situation is further compounded for young amputees who are very quickly out-grow their prosthesis. The proposed artificial muscles are made of nylon fishing strings from various size such as 0.45mm, 0.55mm, 0.65mm and 1.00mm. These fishing strings were twisted into coils to create Super Coiled Polymers (SCP) and tested using hot air blower. These artificial muscles react counterintuitively, where when it is exposed to heat, contracts, and when cooled, expands. Peltier devices, when switched-on acts as heat pump, where one side is hot and the other is cold. This phenomenon, when affixed in between 2 SCP's, creates tandem motion similar to triceps and biceps. As initial study, the hot side of the Peltier module was tested using these artificial muscles. The string was measured for both its force production, length contraction, the initial results were promising.

  20. Defects in alpha and gamma crystalline nylon6: A computational study

    Saeid Arabnejad

    2015-10-01

    Full Text Available We present a comparative Density Functional Tight Binding study of structures, energetics, and vibrational properties of α and γ crystalline phases of nylon6 with different types of defects: single and double chain vacancies and interstitials. The defect formation energies are: for a single vacancy 0.66 and 0.64 kcal/mol per monomer, and for an interstitial strand 1.35 and 2.45 kcal/mol per monomer in the α and γ phases, respectively. The presence of defects does not materially influence the relative stability of the two phases, within the accuracy of the method. The inclusion of phononic contributions has a negligible effect. The calculations show that even if it were possible to synthesize the pure phases of nylon6, the defects will be easily induced at room temperature, because vacancy formation energies in both phases are of the order of kT at room temperature. The formation of interstitial defects, on the contrary, requires the energy equivalent to multiple kT values and is much less likely; it is also much less probable in the γ phase than in α. The vibration spectra do not show significant sensitivity to the presence of these defects.

  1. Catalytic oxidation of butyl acetate over silver-loaded zeolites

    Wong, Cheng Teng; Abdullah, Ahmad Zuhairi; Bhatia, Subhash

    2008-01-01

    The performance of silver-loaded zeolite (HY and HZSM-5) catalysts in the oxidation of butyl acetate as a model volatile organic compound (VOC) was studied. The objective was to find a catalyst with superior activity, selectivity towards deep oxidation product and stability. The catalyst activity was measured under excess oxygen condition in a packed bed reactor operated at gas hourly space velocity (GHSV) = 15,000-32,000 h -1 , reaction temperature between 150 and 500 deg. C and butyl acetate inlet concentration of 1000-4000 ppm. Both AgY and AgZSM-5 catalysts exhibited high activity in the oxidation of butyl acetate. Despite lower silver content, AgY showed better activity, attributed to better metal dispersion, surface characteristics and acidity, and its pore system. Total conversion of butyl acetate was achieved at above 400 deg. C. The oxidation of butyl acetate followed a simple power law model. The reaction orders, n and m were evaluated under differential mode by varying the VOC partial pressure between 0.004 and 0.018 atm and partial pressure of oxygen between 0.05 and 0.20 atm. The reaction rate was independent of oxygen concentration and single order with respect to VOC concentration. The activation energies were 19.78 kJ/mol for AgY and 32.26 kJ/mol for AgZSM-5, respectively

  2. Synthesis of Ag/CNT hybrid nanoparticles and fabrication of their Nylon-6 polymer nanocomposite fibers for antimicrobial applications

    Rangari, Vijaya K; Mohammad, Ghouse M; Jeelani, Shaik; Hundley, Angel; Vig, Komal; Singh, Shree Ram; Pillai, Shreekumar

    2010-01-01

    Ag-coated CNTs hybrid nanoparticles (Ag/CNTs) were prepared by ultrasonic irradiation of dimethylformamide (DMF) and silver (I) acetate precursors in the presence of CNTs. The morphology of Ag/CNTs was characterized using x-ray diffraction and transmission electron microscopy (TEM) techniques. The Nylon-6 powder and 1 wt% Ag/CNTs mixture was dispersed uniformly using a noncontact spinning technique. The dried mixture was melted in a single screw extrusion machine and then extruded through an orifice. Extruded filaments were later stretched and stabilized by sequentially passing them through a set of tension adjusters and a secondary heater. The Nylon-6/Ag/CNT hybrid polymer nanocomposite (HPNC) fibers, which were of ∼ 80 μm size, were tested for their tensile properties. The failure stress and modulus of the extruded HPNC fibers (doped with 1% Ag/CNTs) was about 72.19 % and 342.62% higher than the neat extruded Nylon-6 fiber, respectively. DSC results indicated an increase in the thermal stability and crystallization for HPNC fibers. The antibacterial activity of the Ag-coated CNTs, commercial Ag, neat Nylon-6 and plain CNTs were evaluated. Ag-coated CNTs at 25 μg demonstrated good antimicrobial activity against four common bacterial pathogens as tested by the Kirby-Bauer assay. The mean diameters of the zones of inhibition were 27.9 ± 6.72 mm, 19.4 ± 3.64 mm, 21.9 ± 4.33 mm, and 24.1 ± 4.14 mm, respectively, for Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli and Salmonella enterica serovar Typhimurium. By comparison, those obtained using the broad spectrum antibiotic amoxicillin-clavulanic acid were 37.7 ± 2.13 mm, 28.6 ± 4.27 mm, 22.6 ± 1.27 mm, and 27.0 ± 1.41 mm, respectively, for the same strains. The zones of inhibition obtained for Nylon-6 Ag-coated CNT powder at 25 μg were also high, ranging from 15.2 to 25.3 mm in contrast to commercial silver or neat Nylon-6, which did not inhibit the bacterial strains tested. Further, the

  3. The influence of organo-bentonite clay on the processing and mechanical properties of nylon 6 and polystyrene composites

    Araujo, E.M.; Melo, T.J.A.; Santana, L.N.L.; Neves, G.A.; Ferreira, H.C.; Lira, H.L.; Carvalho, L.H.; A'vila, M.M.; Pontes, M.K.G.; Araujo, I.S.

    2004-01-01

    The influence of organoclay on the processing and mechanical properties of nylon 6 and polystyrene was investigated. A bentonite sample from Boa Vista/PB, Northeast of Brazil, was treated with alkyldimethylbenzylammonium chloride. After the treatment, the powder was characterized by thermal analysis and infrared spectroscopy. Composites were prepared by using a Torque rheometer. The results show the intercalation of quaternary ammonium salt in the structure of bentonite and organo-bentonite produced significant changes on the processing of the nylon 6 and polystyrene with increase in the viscosity and rigidity. However, the mechanical properties of polystyrene/organoclay system did not show significant changes

  4. Synthesis of Ag/CNT hybrid nanoparticles and fabrication of their Nylon-6 polymer nanocomposite fibers for antimicrobial applications

    Rangari, Vijaya K; Mohammad, Ghouse M; Jeelani, Shaik [Materials Science and Engineering, Center for Advanced Materials, Tuskegee University, Tuskegee, AL 36088 (United States); Hundley, Angel; Vig, Komal; Singh, Shree Ram; Pillai, Shreekumar, E-mail: rangariv@tuskegee.edu [Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL 36104 (United States)

    2010-03-05

    Ag-coated CNTs hybrid nanoparticles (Ag/CNTs) were prepared by ultrasonic irradiation of dimethylformamide (DMF) and silver (I) acetate precursors in the presence of CNTs. The morphology of Ag/CNTs was characterized using x-ray diffraction and transmission electron microscopy (TEM) techniques. The Nylon-6 powder and 1 wt% Ag/CNTs mixture was dispersed uniformly using a noncontact spinning technique. The dried mixture was melted in a single screw extrusion machine and then extruded through an orifice. Extruded filaments were later stretched and stabilized by sequentially passing them through a set of tension adjusters and a secondary heater. The Nylon-6/Ag/CNT hybrid polymer nanocomposite (HPNC) fibers, which were of {approx} 80 {mu}m size, were tested for their tensile properties. The failure stress and modulus of the extruded HPNC fibers (doped with 1% Ag/CNTs) was about 72.19 % and 342.62% higher than the neat extruded Nylon-6 fiber, respectively. DSC results indicated an increase in the thermal stability and crystallization for HPNC fibers. The antibacterial activity of the Ag-coated CNTs, commercial Ag, neat Nylon-6 and plain CNTs were evaluated. Ag-coated CNTs at 25 {mu}g demonstrated good antimicrobial activity against four common bacterial pathogens as tested by the Kirby-Bauer assay. The mean diameters of the zones of inhibition were 27.9 {+-} 6.72 mm, 19.4 {+-} 3.64 mm, 21.9 {+-} 4.33 mm, and 24.1 {+-} 4.14 mm, respectively, for Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli and Salmonella enterica serovar Typhimurium. By comparison, those obtained using the broad spectrum antibiotic amoxicillin-clavulanic acid were 37.7 {+-} 2.13 mm, 28.6 {+-} 4.27 mm, 22.6 {+-} 1.27 mm, and 27.0 {+-} 1.41 mm, respectively, for the same strains. The zones of inhibition obtained for Nylon-6 Ag-coated CNT powder at 25 {mu}g were also high, ranging from 15.2 to 25.3 mm in contrast to commercial silver or neat Nylon-6, which did not inhibit the bacterial

  5. The effect of ambient ozone and humidity on the performance of nylon and Teflon filters used in ambient air monitoring filter-pack systems

    PE Padgett

    2010-01-01

    Nylon and Teflon filter media are frequently used for monitoring ambient air pollutants. These media are subject to many environmental factors that may influence adsorption and retention of particulate and gaseous nitrogenous pollutants. This study evaluated the effects of ozone and humidity on the efficacy of nylon and Teflon filters used in the US dry deposition...

  6. The use of nylon and glass fiber filter separators with different pore sizes in air-cathode single-chamber microbial fuel cells

    Zhang, Xiaoyuan; Cheng, Shaoan; Huang, Xia; Logan, Bruce E.

    2010-01-01

    on performance. Larger pore nylon mesh were used that had regular mesh weaves with pores ranging from 10 to 160 μm, while smaller pore-size nylon filters (0.2-0.45 μm) and glass fiber filters (0.7-2.0 μm) had a more random structure. The pore size of both types

  7. Anaerobic degradation of methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA).

    Finneran, K T; Lovley, D R

    2001-05-01

    The potential for anaerobic degradation of methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) was investigated in laboratory incubations of sediments from a petroleum-contaminated aquifer and in aquatic sediments. The addition of humic substances (HS) stimulated the anaerobic degradation of MTBE in aquifer sediments in which Fe(III) was available as an electron acceptor. This is attributed to the fact that HS and other extracellular quinones can stimulate the activity of Fe(III)-reducing microorganisms by acting as an electron shuttle between Fe(III)-reducing microorganisms and insoluble Fe(III) oxides. MTBE was not degraded in aquifer sediments without Fe(III) and HS. [14C]-MTBE added to aquatic sediments adapted for anaerobic MTBE degradation was converted to 14CO2 in the presence or absence of HS or the HS analog, anthraquione-2,6-disulfonate. Unamended aquatic sediments produced 14CH4 as well as 14CO2 from [14C]-MTBE. The aquatic sediments also rapidly consumed TBA under anaerobic conditions and converted [14C]-TBA to 14CH4 and 14CO2. An adaptation period of ca. 250-300 days was required prior to the most rapid anaerobic MTBE degradation in both sediment types, whereas TBA was metabolized in the aquatic sediments without a lag. These results demonstrate that, under the appropriate conditions, MTBE and TBA can be degraded in the absence of oxygen. This suggests that it may be possible to design strategies for the anaerobic remediation of MTBE in petroleum-contaminated subsurface environments.

  8. Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate

    Binder, Thomas [Archer Daniels Midland Company, Decatur, IL (United States); Erpelding, Michael [Archer Daniels Midland Company, Decatur, IL (United States); Schmid, Josef [Archer Daniels Midland Company, Decatur, IL (United States); Chin, Andrew [Archer Daniels Midland Company, Decatur, IL (United States); Sammons, Rhea [Archer Daniels Midland Company, Decatur, IL (United States); Rockafellow, Erin [Archer Daniels Midland Company, Decatur, IL (United States)

    2015-04-10

    Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate. The purpose of Archer Daniels Midlands Integrated Biorefinery (IBR) was to demonstrate a modified acetosolv process on corn stover. It would show the fractionation of crop residue to distinct fractions of cellulose, hemicellulose, and lignin. The cellulose and hemicellulose fractions would be further converted to ethanol as the primary product and a fraction of the sugars would be catalytically converted to acrylic acid, with butyl acrylate the final product. These primary steps have been demonstrated.

  9. Study concerning the compatibility of the mixture of nylon-6 and poly(propylene oxide) through solid state NMR

    Tavares, Maria I.B.; Costa, D.A.; Menezes, Sonia M.C.

    1993-01-01

    NMR has been frequently used for the determination of polymers compatibility. The utilization of the simple pulse technique together with the contact time variation technique has been enabling the evaluation of the compatibility of polymeric systems. This work presents the study of the behaviour of the mixture composed by nylon-6 with poly(propylene oxide) using these techniques. Results are presented

  10. Rumen escape protein in grass and grass silage deterimened with a nylon bag and an enzymatic technique

    Cone, J.W.; Gelder, van A.H.; Mathijssen-Kamman, A.A.; Hindle, V.A.

    2004-01-01

    Rumen escape protein (REP) was determined for six grasses and 16 grass silages using a nylon bag technique and an in vitro technique using a proteolytic enzyme preparation of Streptomyces griseus. In vitro, the samples were incubated for 0, 1, 6 and 24 h. The highest correlation observed between

  11. The Cyclohexanol Cycle and Synthesis of Nylon 6,6: Green Chemistry in the Undergraduate Organic Laboratory

    Dintzner, Matthew R.; Kinzie, Charles R.; Pulkrabek, Kimberly; Arena, Anthony F.

    2012-01-01

    A one-term synthesis project that incorporates many of the principles of green chemistry is presented for the undergraduate organic laboratory. In this multistep scheme of reactions, students react, recycle, and ultimately convert cyclohexanol to nylon 6,6. The individual reactions in the project employ environmentally friendly methodologies, and…

  12. Estudo experimental comparando o uso do 2-octil cianoAcrilato ao nylon 4-0 na sutura da pele

    Ruffo de Freitas-Júnior

    Full Text Available OBJETIVO: Comparar o 2-octil cianoacrilato com o fio de "nylon" no fechamento da pele em ratos. MÉTODOS: Vinte e cinco ratos da linhagem Wistar, foram submetidos à incisão de 3 cm de cada lado do abdome. A síntese foi feita utilizando em um dos lados o "nylon" 4.0, pontos intradérmicos, e do outro o 2-octil cianoacrilato. Após sete dias, o fio foi removido e as incisões, analisadas quanto às complicações. Após 40 dias, o resultado da cicatriz foi avaliado. Os ratos foram sacrificados, as cicatrizes foram ressecadas, fixadas e enviadas ao patologista, sem informação sobre qual o método utilizado. RESULTADOS: Houve dois óbitos durante a anestesia e um tardio. O tempo de operação foi de 136 segundos com a cola e 176 segundos, com o "nylon" (P=0,003. Dentre as 50 operações realizadas, as complicações foram: um hematoma com cada método (P=0,80, quinze deiscências da cola contra 11 do "nylon" (P=0,20, sete cicatrizes de aspecto ruim ou razoável da cola contra quatro do "nylon" (P=0,30, três infecções na cola contra duas (P=0,40. Ao exame patológico, a mediana da largura da cicatriz foi de 1.119 micra com a cola e 1.800 com o "nylon" (P=0,40. A espessura foi de 1.795 contra 1.705 micra (P=0,40. CONCLUSÃO: O 2-octil cianoacrilato apresentou o mesmo aspecto cicatricial, a mesma resistência e as mesmas complicações que a sutura com o "nylon" 4.0, porém permitindo redução no tempo cirúrgico.

  13. Investigation of some properties of Nylon-6 surface treated by corona discharge in helium

    Dumitrascu, N.; Surdu, S.; Popa, Gh.; Raileanu, D.

    1996-01-01

    In this work an easy and less expensive method of treatment has been used by corona discharge. This allows to modify the surface properties and especially to improve the compatibility of polymers with biological tissue. The Nylon-6 as a test material was chosen. A scanning electron microscope to visualize the morphology of the morphology of the surface and an IR spectrophotometer able to identify the amide groups and other as well, have been used. Morphology of the treated surface by corona discharge emphasis an etching an etching and/or a crosslinking of amorphous domains, generally important to improve the properties as wetting, dyeing, adhesion, etc. Over all treated surface there is significant blood compatible properties without the need of heparinization of surface. The treated surface influences the biological behaviour of micro-organisms, respectively, that surface is a favourable medium for division of cells and may increase their lifetime. (authors)

  14. Monitoring of Glucose in Beer Brewing by a Carbon Nanotubes Based Nylon Nanofibrous Biosensor

    Marco Mason

    2016-01-01

    Full Text Available This work presents the design, preparation, and characterization of a novel glucose electrochemical biosensor based on the immobilization of glucose oxidase (GOX into a nylon nanofibrous membrane (NFM prepared by electrospinning and functionalized with multiwalled carbon nanotubes (CNT. A disc of such GOX/CNT/NFM membrane (40 μm in thickness was used for coating the surface of a glassy carbon electrode. The resulting biosensor was characterized by cyclic voltammetry and chronoamperometry, with ferrocene methanol as mediator. The binding of GOX around the CNT/NFM greatly enhances the electron transfer, which results in a biosensor with a current five times higher than without CNT. The potential usefulness of the proposed biosensor was demonstrated with the analysis of glucose in commercial beverages and along the monitoring of the brewing process for making beer, from the mashing to the fermentation steps.

  15. The effect of mechanical drawing on optical and structural properties of nylon 6 fibres

    El-Bakary, M. A.

    2007-09-01

    The Pluta polarizing double-refracting interference microscope was attached to a mechanical drawing device to study the effect of cold drawing on the optical and structural properties of nylon 6 fibres. The microscope was used in its two positions for determining the refractive indices and birefringence of fibres. Different applied stresses and strain rates were obtained using the mechanical-drawing device. The effect of the applied stresses on the optical and physical parameters was investigated. The resulting optical parameters were utilized to investigate the polarizability per unit volume, the optical orientation factor, the orientation angle and the average work per chain. The refractive index and birefringence profiles were measured. Relationships between the average work per chain and optical parameters at different strains rates were determined. An empirical formula was deduced for these fibres. Micro-interferograms are given for illustration.

  16. Functionally graded Nylon-11/silica nanocomposites produced by selective laser sintering

    Chung, Haseung; Das, Suman

    2008-01-01

    Selective laser sintering (SLS), a layered manufacturing-based freeform fabrication approach was explored for constructing three-dimensional structures in functionally graded polymer nanocomposites. Here, we report on the processing and properties of functionally graded polymer nanocomposites of Nylon-11 filled with 0-10% by volume of 15 nm fumed silica nanoparticles. SLS processing parameters for the different compositions were developed by design of experiments (DOE). The densities and micro/nanostructures of the nanocomposites were examined by optical microscopy and transmission electron microscopy (TEM). The tensile and compressive properties for each composition were then tested. These properties exhibit a nonlinear variation as a function of filler volume fraction. Finally, two component designs exhibiting a one-dimensional polymer nanocomposite material gradient were fabricated. The results indicate that particulate-filled functionally graded polymer nanocomposites exhibiting a one-dimensional composition gradient can be successfully processed by SLS to produce three-dimensional components with spatially varying mechanical properties

  17. Deposition of amino-rich thin films by RF magnetron sputtering of nylon

    Kylian, O; Hanus, J; Choukourov, A; Kousal, J; SlavInska, D; Biederman, H, E-mail: ondrej.kylian@gmail.co [Charles University, Faculty of Mathematics and Physics, V Holesovickach 2, Prague 8, 180 00 (Czech Republic)

    2009-07-21

    RF magnetron sputtering of a nylon target in different gas mixtures was studied in order to evaluate the capability of this process to deposit amino-rich coatings needed in a wide range of biomedical applications. It has been demonstrated that both the deposition rate of the coatings and the surface density of primary amino groups are strongly linked with working gas mixture composition. From this point of view, a sufficiently high deposition rate as well as the highest amine efficiency reaching a NH{sub 2}/C value of 18% was observed in the N{sub 2}/H{sub 2} discharge, which leads to the surface exhibiting a high rate of protein adsorption. (fast track communication)

  18. Electrospun nitrocellulose and nylon: Design and fabrication of novel high performance platforms for protein blotting applications

    Bowlin Gary L

    2007-10-01

    Full Text Available Abstract Background Electrospinning is a non-mechanical processing strategy that can be used to process a variety of native and synthetic polymers into highly porous materials composed of nano-scale to micron-scale diameter fibers. By nature, electrospun materials exhibit an extensive surface area and highly interconnected pore spaces. In this study we adopted a biological engineering approach to ask how the specific unique advantages of the electrospinning process might be exploited to produce a new class of research/diagnostic tools. Methods The electrospinning properties of nitrocellulose, charged nylon and blends of these materials are characterized. Results Nitrocellulose electrospun from a starting concentration of Conclusion The flexibility afforded by electrospinning process makes it possible to tailor blotting membranes to specific applications. Electrospinning has a variety of potential applications in the clinical diagnostic field of use.

  19. Roughage digestion evaluation in horses with total feces collection and mobile nylon bags

    Liziana Maria Rodrigues

    2012-02-01

    Full Text Available This study aimed to evaluate the nutrient digestibility of roughages in horses with total feces collection and mobile bags. Two trials were carried out simultaneously. The first trial evaluated the digestibility of nutrients of coastcross hay (Cynodon dactylon cv. coastcross with total feces collection. The second trial assessed the digestibility of nutrients of alfalfa hay (Medicago sativa, peanut (Arachis pintoi and coastcross hay with mobile bags. This trial was conducted with gastric insertions of nylon bags every 12 hours, and each bag contained 663 mg of feed samples in a proportion of 17 mg DM/cm². Feces and bags were collected directly from the stall floor immediately after excretion. There was no difference between the digestibility of dry matter, crude protein, carbohydrates and hydrolysable carbohydrates of coastcross hay estimated with feces collection and mobile bags. Forage peanut showed high nutrients digestibility, with values close to those observed with alfalfa, indicating potential for use in diets for horses.

  20. and triorganotin(IV) complexes of 2-tert-butyl-4-methyl phenol

    TECS

    -2-Me-4) have been synthesized by the reactions of di-n-butyl and dimethyltin dichlorides and tri-n-butyltin(IV) chloride with 2-tert-butyl-4-methylphenol and triethylamine in tetrahydrofuran. The reaction of triphenyltin chloride with trimethylsilyl-2-t-butyl-4- methylphenoxide in the same solvent however, gives a complex of ...

  1. Reactive-ion etching of nylon fabric meshes using oxygen plasma for creating surface nanostructures

    Salapare, Hernando S.; Darmanin, Thierry; Guittard, Frédéric

    2015-01-01

    Graphical abstract: - Highlights: • Reactive-ion etching (RIE) is employed to nylon 6,6 fabrics to achieve surface texturing and improved wettability. • FTIR spectra of the treated samples exhibited decreased transmittance of amide and carboxylic acid groups due to etching. • Etching is enhanced for higher power plasma treatments and for samples with larger mesh sizes. • Decreased crystallinity was achieved after plasma treatment. • Higher power induced higher negative DC self-bias voltage on the samples that favored anisotropic and aggressive etching. - Abstract: A facile one-step oxygen plasma irradiation in reactive ion etching (RIE) configuration is employed to nylon 6,6 fabrics with different mesh sizes to achieve surface nanostructures and improved wettability for textile and filtration applications. To observe the effects of power and irradiation time on the samples, the experiments were performed using constant irradiation time in varying power and using constant power in varying irradiation times. Results showed improved wettability after the plasma treatment. The FTIR spectra of all the treated samples exhibited decreased transmittance of the amide and carboxylic acid groups due to surface etching. The changes in the surface chemistry are supported by the SEM data wherein etching and surface nanostructures were observed for the plasma-treated samples. The etching of the surfaces is enhanced for higher power plasma treatments. The thermal analysis showed that the plasma treatment resulted in decreased crystallinity. Surface chemistry showed that the effects of the plasma treatment on the samples have no significant difference for all the mesh sizes. However, surface morphology showed that the sizes of the surface cracks are the same for all the mesh sizes but samples with larger mesh sizes exhibited enhanced etching as compared to the samples with smaller mesh sizes. Higher power induced higher negative DC self-bias voltage on the samples that

  2. Polymerization behavior of butyl bis(hydroxymethyl)phosphine oxide ...

    lenovo

    Polymerization behavior of butyl bis(hydroxymethyl)phosphine oxide: Phosphorus containing polyethers for. Li‒ion conductivities. Heeralal Vignesh Babu, Billakanti Srinivas and Krishnamurthi Muralidharan*. School of Chemistry, University of Hyderabad, Hyderabad - 500046, India. Table of Contents. TGA plots of SPE2.

  3. 76 FR 5696 - Fluazifop-P-butyl; Pesticide Tolerances

    2011-02-02

    ...: This regulation establishes tolerances for residues of fluazifop-P-butyl in or on multiple commodities... based on maternal body weight gain decrement during GD 7- 16. Incidental oral intermediate- NOAEL= 0.74....0 and 2% at 200 mg dose.) mg/kg/day based on fetal UFA = 10x weight decrement, UFH = 10x hydroureter...

  4. 27 CFR 21.101 - tert-Butyl alcohol.

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false tert-Butyl alcohol. 21.101 Section 21.101 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21...

  5. Critical behavior in the system cyclopentanone + water + secondary butyl alcohol

    Krishna, U. Santhi; Unni, P. K. Madhavan

    2018-05-01

    We report detailed measurements of coexistence surface in the ternary system cylcopentanone + water + secondary butyl alcohol. The coexistence surface is seen to have an unusual tunnel like feature and is a potential system in which special critical points such as the Quadruple Critical Point (QCP) could be studied. Analysis of coexistence curves indicates that the system shows 3D-Ising like critical behavior.

  6. 27 CFR 21.100 - n-Butyl alcohol.

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false n-Butyl alcohol. 21.100 Section 21.100 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21...

  7. A Study of the Teratogenicity of Butylated Hydroxyanisole on Rabbits

    Hansen, Ernst; Meyer, Otto A.

    1978-01-01

    A teratogenicity study on butylated hydroxyanisole (BHA) was carried out in SPF New Zealand White rabbits. BHA was given by gavage from day 7–18 of the gestation period in doses of 0, 50, 200 and 400 mg/kg body wt./day. The fetuses were removed on day 28. No effect related to the treatment with BHA...

  8. Atom transfer radical copolymerization of styrene and butyl acrylate

    Chambard, G.; Klumperman, B.; Matyjaszewski, K.

    2000-01-01

    Atom transfer radical polymerization of styrene and butyl acrylate has been investigated from a kinetic point of view. Attention is focused on the activation of the dormant species as well as on the termination that plays a role in these reactions. It has been shown that the activation of a styrene

  9. Enhanced Heterogeneous Catalytic Conversion of Furfuryl Alcohol into Butyl Levulinate

    Carà, P.D..; Ciriminna, R.; Shiju, N.R.; Rothenberg, G.; Pagliaro, M.

    2014-01-01

    We study the catalytic condensation of furfuryl alcohol with 1-butanol to butyl levulinate. A screening of several commercial and as-synthesized solid acid catalysts shows that propylsulfonic acid-functionalized mesoporous silica outperforms the state-of-the-art phosphotungstate acid catalysts. The

  10. Microwave-assisted grafting polymerization modification of nylon 6 capillary-channeled polymer fibers for enhanced weak cation exchange protein separations

    Jiang, Liuwei; Marcus, R. Kenneth, E-mail: marcusr@clemson.edu

    2017-02-15

    A weak cation exchange liquid chromatography stationary phase (nylon-COOH) was prepared by grafting polyacrylic acid on to native nylon 6 capillary-channeled polymer (C-CP) fibers via a microwave-assisted radical polymerization. To the best of our knowledge, this is the first study of applying microwave-assisted grafting polymerization to affect nylon material for protein separation. The C-CP fiber surfaces were characterized by attenuated total reflection (ATR) infrared spectroscopy and scanning electron microscope (SEM). The anticipated carbonyl peak at 1722.9 cm{sup −1} was found on the nylon-COOH fibers, but was not found on the native fiber, indicating the presence of the polyacrylic acid on nylon fibers after grafting. The nylon-COOH phase showed a ∼12× increase in lysozyme dynamic binding capacity (∼12 mg mL{sup −1}) when compared to the native fiber phase (∼1 mg mL{sup −1}). The loading capacity of the nylon-COOH phase is nearly independent of the lysozyme loading concentration (0.05–1 mg mL{sup −1}) and the mobile phase linear velocity (7.3–73 mm s{sup −1}). The reproducibility of the lysozyme recovery from the nylon-COOH (RSD = 0.3%, n = 10) and the batch-to-batch variability in the functionalization (RSD = 3%, n = 5) were also investigated, revealing very high levels of consistency. Fast baseline separations of myoglobin, α-chymotrypsinogen A, cytochrome c and lysozyme were achieved using the nylon-COOH column. It was found that a 5× increase in the mobile phase linear velocity (7.3-to-36.5 mm s{sup −1}) had little effect on the separation resolution. The microwave-assisted grafting polymerization has great potential as a generalized surface modification methodology across the applications of C-CP fibers. - Highlights: • A microwave-assisted grafting method to attach acrylic acid is described for the first time for chromatographic phases. • A high-density, weak cation exchange surface is created on a nylon

  11. Multiple cutaneous leiomyomas: Pain relief with pulsed hysocine butyl bromide

    Kaliyadan Feroze

    2009-01-01

    Full Text Available A 35-year-old male patient presented to our outpatient department, complaining of multiple, raised skin lesions on the forehead and back, associated with intermittent pain, especially on exposure to cold. A diagnosis of cutaneous leiomyoma (type 2 segmental was made, which was confirmed by skin biopsy. The patient was started on a trial of pulsed Hyoscine Butyl bromide tablets, following which the patient had significant relief from pain associated with the lesions.

  12. Study of the butyl acetate synthesis - 1. Catalyst selection

    Álvaro Orjuela Londoño

    2004-01-01

    Full Text Available In this work, a laboratory scale selection study over eight catalytic agents was made, in the acetic acid and butyl alcohol esterification reaction (seven lon exchange resins and a zeolytic solid. Considering some physicochemical characteristics as the activation pre-treating requirements, acidity, thermal stability, reaction performance, etc., it was found that macroporous ion exchange resins are the most efficient catalysts, especially Lewatit K-2431 resin.

  13. Glycerol tertiary butyl ethers via etherification of glycerol with isobutene

    Behr, A. [Dortmund Univ. (Germany). Chair of Chemical Process Development/Technical Chemistry A

    2007-07-01

    Glycerol and isobutene can react to a mixture of glycerol tertiary butyl ethers (GTBE) which can be used as additives for gasoline, diesel or biodiesel. This reaction was investigated in lab scale yielding a proposal for a process flow diagram containing reaction, extraction, flash and rectification units. This process has the advantages that only the suitable higher ethers are formed and that both glycerol and isobutene are fully converted. The homogeneous acid catalyst is low-priced and can be completely recycled. (orig.)

  14. Solution of a gallstone with methyl-tertiary butyl ether

    Brambs, H J; Roeren, T; Holstege, A; Raedecke, J

    1987-08-01

    Methyl-t-butyl ether is a new agent to dissolve gallstones. The substance proves to be very successful and acts very rapidly. A percutaneous transhepatic drainage supplies an adequate access route to dissolve calculi within the bile ducts. We report the case of a patient where before insertion of an internal stent a stone in the common bile duct was dissolved within 3 1/2 hours.

  15. Analysing chemical equilibrium conditions when studying butyl acetate synthesis

    Álvaro Orjuela Londoño; Fernando Leiva Lenis; Luis Alejandro Boyacá Mendivelso; Gerardo Rodríguez Niño; Luis María Carballo Suárez

    2010-01-01

    This work studied the liquid phase of acetic acid and butyl alcohol esterification reaction (P atm = 560 mmHg),using an ion exchange resin (Lewatit K-2431) as catalyst. A set of assays were carried out for determining the effect of catalyst load, temperature and molar ratio (acid/alcohol) on chemical equilibrium constant. Components’ selective sorption on the resin matrix was noticed; its effect on equilibrium conditions was verified, by using different acid/alcohol starting ratios. A non-ide...

  16. Di-iso-Butyl Phthalate MATERNAL AND FETAL DATA FROM ...

    this file contains the raw data on the effects of in utero administration of di-iso-butyl phthalate on maternal weight gain during dosing and the numbers of fetuses and fetal resorptions. The data have all been previously published, as described on the file metadata sheet. Raw data file from our published studies on DIBP specifically requested (6/14/2016) by NCEA scientists for analysis and inclusion in their assessment of this chemical.

  17. Layer-by-Layer Assembly of Halogen-Free Polymeric Materials on Nylon/Cotton Blend for Flame Retardant Applications

    2015-07-01

    Respondents should be aware that notwithstanding any other provision of law , no person shall be subject to any penalty for failing to comply with a collection...BY-LAYER ASSEMBLY OF HALOGEN-FREE POLYMERIC MATERIALS ON NYLON/COTTON BLEND FOR FLAME RETARDANT APPLICATIONS 5a. CONTRACT NUMBER W911NF-11-D-0001...Tensile strength and dynamic mechanical analysis. Malaysian Polymer Journal 2009; 4(2):52–61. 29. Hardin IR, Hsieh Y. Thermal conditions and

  18. Thermodynamic properties of 4-tert-butyl-diphenyl oxide

    Druzhinina, A.I.; Pimenova, S.M.; Tarazanov, S.V.; Nesterova, T.N.; Varushchenko, R.M.

    2015-01-01

    Highlights: • The sample of the 4-tert-butyl-diphenyl oxide was synthesized and purified. • Heat capacities, energy of combustion, saturation vapor pressures were measured. • The temperature, the enthalpy and the entropy of fusion were determined. • The enthalpy of sublimation at T = 298.15 K was derived. • The main thermodynamic functions and functions of formation were computed. - Abstract: The main thermodynamic functions (changes of the entropy, enthalpy, and Gibbs free energy) and functions of formation at T = 298.15 K of 4-tert-butyl-diphenyl oxide in condensed and ideal gas states were computed on the basis of experimental results obtained. The heat capacities of 4-tert-butyl-diphenyl oxide was measured by vacuum adiabatic calorimetry over the temperature range (8 to 371) K. The temperature, the enthalpy and the entropy of fusion were determined. The energy of combustion of the sample was determined by static-bomb combustion calorimetry. The saturation vapor pressures of the substance were measured by dynamic transpiration method over the temperature and pressure intervals (298 to 325) K and (0.05 to 1.2) Pa. The enthalpy of sublimation at T = 298.15 K was derived. The contribution of O-(2C b ) group (where C b is the carbon atom in a benzene ring) into the absolute entropies of diphenyl oxide derivatives was assessed

  19. Effects of the Addition of Ortho- and Para-NH2 Substituted Tetraphenylporphyrins on the Structure of Nylon 66

    Luis A. Díaz-Alejo

    2013-01-01

    Full Text Available The synthetic tetrapyrrole macrocycles, such as porphyrins (H2P and phthalocyanines (H2Pc, exhibit interesting physicochemical properties suitable to be used in modern technology. For many applications, those species should be trapped or fixed inside graphite, hydrotalcites, silica, TiO2, or polymers. Methodologies for the optimization of the properties of porphyrins, trapped or fixed inside polymers, have been barely developed. Our research works in the development of methodologies for the optimization of incorporation and display of properties of tetrapyrrole macrocycles inside inorganic, polymeric, or hybrid networks. This paper shows some results about the effect of the spatial disposition of the amine (–NH2 groups attached on the periphery of substituted tetraphenylporphyrins, on the Nylon 66 structure and on the display of the physicochemical properties of the trapped macrocycles. Nylon 66 was synthesized from adipoyl chloride and hexamethylenediamine in presence of tetraphenylporphyrins substituted with –NH2 groups localized at the ortho- or para-positions of the phenyls. Cobalt complexes formation was used to quantify the amount of porphyrins in the polymer fibers. Characterization results show that the spatial position of amine groups of the porphyrins has important structural and textural effect on the Nylon 66 fibers and on the fluorescence of the porphyrins integrated into the fibers.

  20. Effects of sequence of nylon bags rumen incubation on kinetics of degradation in some commonly used feedstuffs in dairy rations

    DONG Shuang-zhao; Arash Azarfar; ZOU Yang; LI Sheng-li; WANG Ya-jing; CAO Zhi-jun

    2017-01-01

    Nowadays, most available information on the degradative behaviour of feeds in ruminants is based onin situ incubation in the rumen, and it is adopted by many feed evaluation systems currently in use for ruminants. However, the outcome of this technique might be affected by many factors such as sequence of nylon bags incubation in the rumen. The objective of current study was to investigate effects of sequence of nylon bag incubation on degradative behavior of dry matter (DM), crude protein (CP), neutral detergent ifber (NDF) and acid detergent ifber (ADF) in some feed ingredients commonly used in dairy rations, including alfalfa haylage, corn silage, corn grain and soybean meal. Four multiparous Holstein lactating cows iftted with permanent ruminal cannulas were used. The nylon bags containing feed samples either were placed in the rumen at once and removed at designated time intervals (all in-gradually out method; AG) or were placed in the rumen at designated time points and retrieved at once (gradually in-all out method; GA). Fractional rate of degradation of potentially degradable fraction, lag time and effective rumen degradability (ED) of DM and CP were signiifcantly higher in the AG compared to the GA method (P namely corn grain and soybean meal. This experiment is the ifrst time to investigate effects of two methods under the same experiment conditions, providing basic data for the determination of ED.

  1. Highly photoluminescent and photostable CdSe quantum dot-nylon hybrid composites for efficient light conversion applications

    Yuan Ying; Riehle, Frank-Stefan [Freiburg Materials Research Centre (FMF), University of Freiburg, Stefan-Meier-Str. 21, D-79104 Freiburg (Germany); Department of Microsystems Engineering (IMTEK), Georg Koehler Allee 103, University of Freiburg, D-79110 Freiburg (Germany); Nitschke, Roland [Life Imaging Center, Centre of Systems Biology, University of Freiburg Habsburgerstr. 49, D-79104 Freiburg (Germany); Centre for Biological Signalling Studies (BIOSS), University of Freiburg (Germany); Krueger, Michael, E-mail: michael.krueger@fmf.uni-freiburg.de [Freiburg Materials Research Centre (FMF), University of Freiburg, Stefan-Meier-Str. 21, D-79104 Freiburg (Germany); Department of Microsystems Engineering (IMTEK), Georg Koehler Allee 103, University of Freiburg, D-79110 Freiburg (Germany)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer A novel in situ synthesis approach for highly luminescent CdSe core QDs-nylon hybrid materials. Black-Right-Pointing-Pointer Potential applications for light and energy conversion are demonstrated. Black-Right-Pointing-Pointer Three dimensional structures out of this hybrid material are available. - Abstract: Highly photoluminescent hexadecylamine (HDA) capped core CdSe quantum dots (QDs) with fluorescent quantum yields (QYs) up to 60% were synthesized using a hot injection method and directly incorporated into nylon polymer. For the incorporation of crude CdSe QDs into nylon a simple reproducible and upscalable one pot approach was developed without the need of further purification steps. The photoluminescence (PL) properties of the core QDs and the resulting QD-polymer hybrid composites were investigated and compared. Red emitting hybrid materials exhibit a QY of 60% with a high potential for applications in direct light and energy conversion. The hybrid materials could be successfully utilized as LED conversion layers. By avoiding exposure to oxygen the hybrid films can be kept for a month without detecting a significant decrease in luminescence. Various three dimensional structures are easily available opening doors for further applications such as novel materials for fluorescence standard development in laser scanning microscopy (LSM).

  2. Uncertainties of Gaseous Oxidized Mercury Measurements Using KCl-Coated Denuders, Cation-Exchange Membranes, and Nylon Membranes: Humidity Influences.

    Huang, Jiaoyan; Gustin, Mae Sexauer

    2015-05-19

    Quantifying the concentration of gaseous oxidized mercury (GOM) and identifying the chemical compounds in the atmosphere are important for developing accurate local, regional, and global biogeochemical cycles. The major hypothesis driving this work was that relative humidity affects collection of GOM on KCl-coated denuders and nylon membranes, both currently being applied to measure GOM. Using a laboratory manifold system and ambient air, GOM capture efficiency on 3 different collection surfaces, including KCl-coated denuders, nylon membranes, and cation-exchange membranes, was investigated at relative humidity ranging from 25 to 75%. Recovery of permeated HgBr2 on KCl-coated denuders declined by 4-60% during spikes of relative humidity (25 to 75%). When spikes were turned off GOM recoveries returned to 60 ± 19% of permeated levels. In some cases, KCl-coated denuders were gradually passivated over time after additional humidity was applied. In this study, GOM recovery on nylon membranes decreased with high humidity and ozone concentrations. However, additional humidity enhanced GOM recovery on cation-exchange membranes. In addition, reduction and oxidation of elemental mercury during experiments was observed. The findings in this study can help to explain field observations in previous studies.

  3. Isolation of uv-sensitive variants of CHO-Kl by nylon cloth replicaplating

    Stamato, T.D.; Waldren, C.A.

    1977-01-01

    Techniques are described which permit the identification and isolation of uv-sensitive variants from mutagenized populations of Chinese hamster ovary (CHO) cells. Identification is based on the observation that within two days after receiving a dose of approximately 240 ergs/mm 2 of uv irradiation, most of the cells in a colony of CHO detach from the surface of a plastic tissue culture dish. At a lower dose of uv, which does not kill or detach a significant number of parental cells, uv-sensitive colonies are killed and become detached. Thus a clear plaque is produced in a lawn of unirradiated parental cells, marking the site occupied by a sensitive colony. Live cells from such sensitive colonies have been recovered from a nylon cloth replica prepared prior to irradiation and characterized. One uv-sensitive variant (CHO-UV-1) is indistinguishable from parental cells in x-ray resistance, chromosome number, generation time, and duration of the phases of the cell cycle

  4. [Vehicle-assisted suicide with a nylon rope causing complete decapitation].

    Blässer, Katharina; Tatschner, Thomas; Bohnert, Michael

    2013-01-01

    The present case deals with the unusual suicide method of a 36-year-old man who fastened one end of a nylon rope to a tree, guided the other end into a van through the open tailgate and placed the loop round his neck. Then he stepped on the accelerator. Before, he had marked the point on the ground where the rope would tighten. As the rope tightened complete decapitation occurred at a speed of about 35 km/h. Autopsy showed a nearly circular abrasion zone around the site of transection slightly ascending towards the nape, a fracture of the cervical spine between the 3rd and 4th vertebra and a fracture of the thoracic spine between the 7th and 8th vertebra. The test for air embolism of the heart was positive. Macroscopically, no evidence of blood aspiration was found. Histological investigation showed general anaemia and minor blood aspiration in the lungs. Wound morphology was largely in line with the injury patterns described after decapitation in the literature. However, our results differed in that blood aspiration was discernible only under the microscope and there was a second fracture of the spine. Decapitation as a suicide method is an expression of enormous autoaggression and is categorized as a "hard" suicide method. It is used predominantly by men and its occurrence in the spectrum of suicidal actions is rare. Police investigations revealed that the man had led a sort of double life with a sexually motivated background and had suffered from depressive episodes.

  5. Physicochemical characterization of chitosan/nylon6/polyurethane foam chemically cross-linked ternary blends.

    Jayakumar, S; Sudha, P N

    2013-03-15

    Chitosan/nylon6/polyurethane foam (CS/Ny6/PUF) ternary blend was prepared and chemically cross-linked with glutaraldehyde. Structural, thermal and morphological studies were performed for the prepared ternary blends. Characterizations of the ternary blends were investigated by Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and scanning electron microscope (SEM). The FTIR results showed that the strong intermolecular hydrogen bonds took place between CS, Ny6 and PUF. TGA and DSC studies reveal that the thermal stability of the blend is enhanced by glutaraldehyde as crosslinking agent. Results of XRD indicated that the relative crystalline of pure CS film was reduced when the polymeric network was reticulated by glutaraldehyde. Finally, the results of scanning electron microscopy (SEM) indicated that the morphology of the blend is rough and heterogeneous, further it confirms the interaction between the functional groups of the blend components. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Mechanical and Morphological Properties of Short Nylon Fiber Reinforced Acrylonitrile-Butadiene Rubber Composites

    S.H. Mohseniyan

    2010-12-01

    Full Text Available Acrylonitrile butadiene rubber (NBR composites are prepared from waste nylon 66 short fiber using a two-roll mill mixer. The effects of fiber content and bonding agent on the mechanical and morphological properties of the composites are studied. The curing characteristics of the composites have been studied by using cure rheometer. The cure and scorch time of the composites decrease while cure rate is increased when short fiber content is increased. The mechanical properties of the composites show improvement in both longitudinal and transverse directions with increase in short fiber content. The adhesion between the fiber and rubber is enhanced by using a dry bonding system consisting of resorcinol, xamethylenetetramine and hydrated silica (HRH. The swelling behavior of the composites in N,N-dimethylformamide is tested to find the effect of bonding agent on adhesion strength of the matrix and fibers. Fracture surface morphology of composites is studied by scanning electron microscopy. The restriction to swelling is higher for composites containing bonding agent, especially, in the longitudinal direction. The morphology of the fracture surface shows less fiber pull out when the bonding agent is introduced.

  7. Candidiasis in HIV and AIDS Patients Attending the Nylon Health District Hospital in Douala, Cameroon

    Anna Longdoh Njunda

    2011-12-01

    Full Text Available AIM: Candidiasis is the leading opportunistic mycosis in HIV and AIDS patients. METHOD: In order to determine its prevalence in patients with different CD4+ T cell categories in the Nylon Health District in Douala, a cross-sectional study was carried out whereby 304 HIV positive individuals were recruited between March and August, 2007. They were divided into two groups; those on highly active antiretroviral therapy (HAART and those not on HAART. Three samples constituting mouth, vaginal/urethral swabs and urine were collected from each subject. RESULTS: A total of 204 (67.1% [95% confidence interval (CI: 0.618-0.724] of these patients had more than one predisposing condition to candidiasis, with those on antibiotic therapy having the highest prevalence (63.7% followed by pregnant patients (7.3% (P < 0.05. Candidiasis was more common in patients with low CD4+ T cell count (<200 [66%] than patients with higher CD4+ T cell count (17.9% (P<0.05. One hundred and sixty one (53% of the patients had candidiasis whereby those not on HAART were more frequently infected (69.6% than those on HAART (30.1% (P< 0.05. CONCLUSION: We conclude that candidiasis is a major opportunistic infection in HIV patients and should be checked especially in patients not yet on antiretroviral therapy. [TAF Prev Med Bull 2011; 10(6.000: 701-706

  8. Flexure and impact properties of glass fiber reinforced nylon 6-polypropylene composites

    Kusaseh, N. M.; Nuruzzaman, D. M.; Ismail, N. M.; Hamedon, Z.; Azhari, A.; Iqbal, A. K. M. A.

    2018-03-01

    In recent years, polymer composites are rapidly developing and replacing the metals or alloys in numerous engineering applications. These polymer composites are the topic of interests in industrial applications such as automotive and aerospace industries. In the present research study, glass fiber (GF) reinforced nylon 6 (PA6)-polypropylene (PP) composite specimens were prepared successfully using injection molding process. Test specimens of five different compositions such as, 70%PA6+30%PP, 65%PA6+30%PP+5%GF, 60%PA6+30%PP+10%GF, 55%PA6+30%PP+15%GF and 50%PA6+30%PP+20%GF were prepared. In the experiments, flexure and impact tests were carried out. The obtained results revealed that flexure and impact properties of the polymer composites were significantly influenced by the glass fiber content. Results showed that flexural strength is low for pure polymer blend and flexural strength of GF reinforced composite increases gradually with the increase in glass fiber content. Test results also revealed that the impact strength of 70%PA6+30%PP is the highest and 55%PA6+30%PP+15%GF composite shows moderate impact strength. On the other hand, 50%PA6+30%PP+20%GF composite shows low toughness or reduced impact strength.

  9. The evaluation of nylon and polyethylene as build-up material in a neutron therapy beam

    Hough, J.H.; Binns, P.J.

    1995-01-01

    In high-energy neutron beams a substantial amount of build-up material is required to irradiate biological samples under conditions of charged particle equilibrium. Ideally A-150 tissue-equivalent plastic is used for this purpose. This material is however not always readily available and hence the need for a substitute compound. The selected hydrocarbon should satisfy two requirements: the quality of the radiation on the distal side needs to be the same as that measured for A-150 plastic and the absorbed dose should remain consistent. A tissue-equivalent proportional counter operating at reduced pressure not only measures the absorbed dose accurately but provides a means for assessing the nature of a radiation field in terms of a secondary charged particle spectrum. Using build-up caps manufactured from nylon (type 6) and polyethylene, it is shown that the former is an acceptable substitute for A-150 plastic. The data further demonstrate that both the absorbed dose and the spectral character of the measured single-event distribution are altered when polyethylene is used and that these discrepancies are attributable to the higher hydrogen content of polyethylene. (Author)

  10. Influence of Hybrid Fillers on Thermal Conductivity of Nylon-6/Graphene Composites

    SONG Na

    2018-03-01

    Full Text Available The thermal insulating properties of polymer greatly restrict the application of polymer as the thermal conductivity materials in industry. Multilayer graphene was chosen as a filler due to its unique thermal transfer property. The effect of alumina oxide (Al2O3 and silicon carbide (SiC with graphene as hybrid fillers on thermal conductivity of polymers was also explored. The thermal conductivity of the composites enhances 161% with 3%(mass fraction graphene content compared to pure nylon-6(PA6. The thermal conductivity of PA6 composites is within 0.653-4.307W·m-1·K-1 by adjusting hybrid fillers content and the ratio of graphene with Al2O3 and SiC. The best thermal conductivity is 20 times higher than the pure PA6. It is no doubt that the exploration can provide valuable experimental basis for extending the utilization of graphene as thermal conductivity filler and the application of PA6 thermal conductivity materials in industry.

  11. Analysis of Dyes Extracted from Millimeter-Size Nylon Fibers by Micellar Electrokinetic Chromatography

    Lewis, L.A.

    2001-01-01

    The Learning Objective is to present to the forensic community a potential qualitative/quantitative method for trace-fiber color comparisons using micellar electrokinetic chromatography (MEKC). Developing a means of analyzing extracted dye constituents from millimeter-size nylon fiber samples was the objective of this research initiative. Aside from ascertaining fiber type, color evaluation and source comparison of trace-fiber evidence plays a critical role in forensic-fiber examinations. Literally thousands of dyes exist to date, including both natural and synthetic compounds. Typically a three-color-dye combination is employed to affect a given color on fiber material. The result of this practice leads to a significant number of potential dye combinations capable of producing a similar color and shade. Since a typical forensic fiber sample is 2 mm or less in length, an ideal forensic dye analysis would qualitatively and quantitatively identify the extracted dye constituents from a sample size of 1 mm or smaller. The goal of this research was to develop an analytical method for comparing individual dye constituents from trace-fiber evidence with dyes extracted from a suspected source, while preserving as much of the original evidence as possible

  12. Medium Effects on Minimum Inhibitory Concentrations of Nylon-3 Polymers against E. coli

    Choi, Heejun; Chakraborty, Saswata; Liu, Runhui; Gellman, Samuel H.; Weisshaar, James C.

    2014-01-01

    Minimum inhibitory concentrations (MICs) against E. coli were measured for three nylon-3 polymers using Luria-Bertani broth (LB), brain-heart infusion broth (BHI), and a chemically defined complete medium (EZRDM). The polymers differ in the ratio of hydrophobic to cationic subunits. The cationic homopolymer is inert against E. coli in BHI and LB, but becomes highly potent in EZRDM. A mixed hydrophobic/cationic polymer with a hydrophobic t-butylbenzoyl group at its N-terminus is effective in BHI, but becomes more effective in EZRDM. Supplementation of EZRDM with the tryptic digest of casein (often found in LB) recapitulates the LB and BHI behavior. Additional evidence suggests that polyanionic peptides present in LB and BHI may form electrostatic complexes with cationic polymers, decreasing activity by diminishing binding to the anionic lipopolysaccharide layer of E. coli. In contrast, two natural antimicrobial peptides show no medium effects. Thus, the use of a chemically defined medium helps to reveal factors that influence antimicrobial potency of cationic polymers and functional differences between these polymers and evolved antimicrobial peptides. PMID:25153714

  13. Determining nutrients degradation kinetics of chickpea (Cicer arietinum straw using nylon bag technique in sheep

    A. Mirzaei-Aghsaghali

    2012-05-01

    Full Text Available Straw a by-product from grain legume crops is produced in large quantities in Iran. Straw is constant component of ruminant diets on small holder farms; however, there is little information about its nutritive value. Accordingly experiment was conducted to determine the chemical composition and ruminal organic matter (OM and crude protein (CP degradability of chickpea straw using nylon bags (in situ technique. Replicated samples were incubated at 0, 2, 4, 8, 12, 24, 48 and 72 hours in three rumen canulated Ghezel rams with 50±3 kg body weight. Dry matter (DM, CP, ether extract (EE, OM, crude fiber (CF and nitrogen free extract (NFE content of chickpea straws were 92.2, 6.1, 5.5, 92.0, 34.3 and 46.2%, respectively. The soluble fraction (a of the OM and CP of chickpea straw was 17.5 and 40.8% and potential degradability (a+b of OM and CP was 56.7 and 72.0%, respectively. Effective degradability at different passage rates (2, 5 and 8% per hours for OM was 51.0 44.9 and 40.7% and for CP were 68.4, 64.3 and 61.3%, respectively. In conclusion, based on chemical composition and degradation characteristics, chickpea straw could have moderate nutritive value for ruminants.

  14. Changes in collection efficiency in nylon net filter media through magnetic alignment of elongated aerosol particles.

    Lam, Christopher O; Finlay, W H

    2009-10-01

    Fiber aerosols tend to align parallel to surrounding fluid streamlines in shear flows, making their filtration more difficult. However, previous research indicates that composite particles made from cromoglycic acid fibers coated with small nanoscaled magnetite particles can align with an applied magnetic field. The present research explored the effect of magnetically aligning these fibers to increase their filtration. Nylon net filters were challenged with the aerosol fibers, and efficiency tests were performed with and without a magnetic field applied perpendicular to the flow direction. We investigated the effects of varying face velocities, the amount of magnetite material on the aerosol particles, and magnetic field strengths. Findings from the experiments, matched by supporting single-fiber theories, showed significant efficiency increases at the low face velocity of 1.5 cm s(-1) at all magnetite compositions, with efficiencies more than doubling due to magnetic field alignment in certain cases. At a higher face velocity of 5.12 cm s(-1), filtration efficiencies were less affected by the magnetic field alignment being, at most, 43% higher for magnetite weight compositions up to 30%, while at a face velocity of 10.23 cm s(-1) alignment effects were insignificant. In most cases, efficiencies became independent of magnetic field strength above 50 mT, suggesting full alignment of the fibers. The present data suggest that fiber alignment in a magnetic field may warrant applications in the filtration and detection of fibers, such as asbestos.

  15. Contribution to the study of uranyl salts in butyl phosphate solutions

    Coulon, A.

    1965-06-01

    A spectroscopic study in the normal infrared region and involving the following associations: tri-alkyl phosphates (tri-butyl, tri-ethyl, tri-methyl), uranyl salts (nitrate, chloride, acetate) has confirmed the existence of an interaction between the phosphoryl group and the uranium atom, as shown by a movement of absorption band for the valency P = 0 from ∼ 1270 cm -1 to ∼ 1180 cm -1 . A study of the preparation, analysis and spectroscopy of the solids obtained by the precipitation of uranyl salts by acid butyl phosphates has been carried out. By infrared spectrophotometry it has been shown that the tri-butyl and di-butyl phosphates are associated in non-polar diluents even before the uranium is introduced. The extraction of uranyl salts from acid aqueous solutions by a diluted mixture of tri-butyl and di-butyl phosphates proceeds by different mechanisms according to the nature of the ion (nitrate or chloride). (author) [fr

  16. Innovative UVC light (185 nm) and radio-frequency-plasma pretreatment of Nylon surfaces at atmospheric pressure and their implications in photocatalytic processes.

    Mejía, M I; Marín, J M; Restrepo, G; Pulgarín, C; Mielczarski, E; Mielczarski, J; Stolitchnov, I; Kiwi, J

    2009-10-01

    Innovative pretreatment by UVC light (185 nm) and by radio-frequency (RF) plasma at atmospheric pressure to functionalize the Nylon surface, increasing its bondability toward TiO(2), is reported in this study. In the case of UVC light pretreatment in air, the molar absorption coefficient of O(2)/N(2) at 185 nm is very low and the air in the chamber absorbs very little light from the UVC source before reaching the Nylon sample. Nylon fabrics under RF plasma were also functionalized at atmospheric pressure because of the marked heating effect introduced in the Nylon by the RF plasma. This effect leads to intermolecular bond breaking and oxygenated surface groups in the topmost Nylon layers. Both pretreatments enhanced significantly the photocatalytic discoloration of the red-wine stain in Nylon-TiO(2) compared with samples without pretreatment. The UVC and RF methods in the absence of vacuum imply a considerable cost reduction to functionalize textile surfaces, suggesting a potential industrial application. Red-wine-stain discoloration under simulated sunlight was monitored quantitatively by diffuse-reflectance spectroscopy and by CO(2) evolution. X-ray photoelectron spectroscopy (XPS) was used to monitor the changes of the C, N, and S species on the Nylon topmost layers during the discoloration process. Significant changes in the XPS spectra of Ti 2p peaks were observed during discoloration of the wine spots. Wine stains attenuated the signal of the Ti 2p (458.4 eV) peak in the Nylon-TiO(2)-stained wine sample at time zero (from now on, the time before the discoloration process). Furthermore, a decrease of the wine-related O 1s signal at 529.7 eV and N 1s signal at 399.5 eV was observed during the discoloration process, indicating an efficient catalytic decomposition of the wine pigment on Nylon-TiO(2). X-ray diffraction detected the formation of anatase on the Nylon fibers. High-resolution transmission electron microscopy shows the formation of anatase particles

  17. Inducing PLA/starch compatibility through butyl-etherification of waxy and high amylose starch.

    Wokadala, Obiro Cuthbert; Emmambux, Naushad Mohammad; Ray, Suprakas Sinha

    2014-11-04

    In this study, waxy and high amylose starches were modified through butyl-etherification to facilitate compatibility with polylactide (PLA). Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy and wettability tests showed that hydrophobic butyl-etherified waxy and high amylose starches were obtained with degree of substitution values of 2.0 and 2.1, respectively. Differential scanning calorimetry, tensile testing, and scanning electron microscopy (SEM) demonstrated improved PLA/starch compatibility for both waxy and high amylose starch after butyl-etherification. The PLA/butyl-etherified waxy and high amylose starch composite films had higher tensile strength and elongation at break compared to PLA/non-butyl-etherified composite films. The morphological study using SEM showed that PLA/butyl-etherified waxy starch composites had a more homogenous microstructure compared to PLA/butyl-etherified high amylose starch composites. Thermogravimetric analysis showed that PLA/starch composite thermal stability decreased with starch butyl-etherification for both waxy and high amylose starches. This study mainly demonstrates that PLA/starch compatibility can be improved through starch butyl-etherification. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Open-Source Selective Laser Sintering (OpenSLS) of Nylon and Biocompatible Polycaprolactone.

    Kinstlinger, Ian S; Bastian, Andreas; Paulsen, Samantha J; Hwang, Daniel H; Ta, Anderson H; Yalacki, David R; Schmidt, Tim; Miller, Jordan S

    2016-01-01

    Selective Laser Sintering (SLS) is an additive manufacturing process that uses a laser to fuse powdered starting materials into solid 3D structures. Despite the potential for fabrication of complex, high-resolution structures with SLS using diverse starting materials (including biomaterials), prohibitive costs of commercial SLS systems have hindered the wide adoption of this technology in the scientific community. Here, we developed a low-cost, open-source SLS system (OpenSLS) and demonstrated its capacity to fabricate structures in nylon with sub-millimeter features and overhanging regions. Subsequently, we demonstrated fabrication of polycaprolactone (PCL) into macroporous structures such as a diamond lattice. Widespread interest in using PCL for bone tissue engineering suggests that PCL lattices are relevant model scaffold geometries for engineering bone. SLS of materials with large powder grain size (~500 μm) leads to part surfaces with high roughness, so we further introduced a simple vapor-smoothing technique to reduce the surface roughness of sintered PCL structures which further improves their elastic modulus and yield stress. Vapor-smoothed PCL can also be used for sacrificial templating of perfusable fluidic networks within orthogonal materials such as poly(dimethylsiloxane) silicone. Finally, we demonstrated that human mesenchymal stem cells were able to adhere, survive, and differentiate down an osteogenic lineage on sintered and smoothed PCL surfaces, suggesting that OpenSLS has the potential to produce PCL scaffolds useful for cell studies. OpenSLS provides the scientific community with an accessible platform for the study of laser sintering and the fabrication of complex geometries in diverse materials.

  19. Interaction of CO2 laser-modified nylon with osteoblast cells in relation to wettability

    Waugh, D.G.; Lawrence, J.; Morgan, D.J.; Thomas, C.L.

    2009-01-01

    It has been amply demonstrated previously that CO 2 lasers hold the ability to surface modify various polymers. In addition, it has been observed that these surface enhancements can augment the biomimetic nature of the laser irradiated materials. This research has employed a CO 2 laser marker to produce trench and hatch topographical patterns with peak heights of around 1 μm on the surface of nylon 6,6. The patterns generated have been analysed using white light interferometry, optical microscopy and X-ray photoelectron spectroscopy was employed to determine the surface oxygen content. Contact angle measurements were used to characterize each sample in terms of wettability. Generally, it was seen that as a result of laser processing the contact angle, surface roughness and surface oxygen content increased whilst the apparent polar and total surface energies decreased. The increase in contact angle and reduction in surface energy components was found to be on account of a mixed intermediate state wetting regime owing to the change in roughness due to the induced topographical patterns. To determine the biomimetic nature of the modified and as-received control samples each one was seeded with 2 x 10 4 cells/ml normal human osteoblast cells and observed after periods of 24 h and 4 days using optical microscopy and SEM to determine mean cell cover densities and variations in cell morphology. In addition, a haemocytometer was used to show that the cell count for the laser patterned samples had increased by up to a factor of 1.5 compared to the as-received control sample after 4 days of incubation. Significantly, it was determined that all laser-induced patterns gave rise to better cell response in comparison to the as-received control sample studied due to increased preferential cell growth on those surfaces with increased surface roughness.

  20. Diagnostics of microwave assisted electron cyclotron resonance plasma source for surface modification of nylon 6

    More, Supriya E.; Das, Partha Sarathi; Bansode, Avinash; Dhamale, Gayatri; Ghorui, S.; Bhoraskar, S. V.; Sahasrabudhe, S. N.; Mathe, Vikas L.

    2018-01-01

    Looking at the increasing scope of plasma processing of materials surface, here we present the development and diagnostics of a microwave assisted Electron Cyclotron Resonance (ECR) plasma system suitable for surface modification of polymers. Prior to the surface-treatment, a detailed diagnostic mapping of the plasma parameters throughout the reactor chamber was carried out by using single and double Langmuir probe measurements in Ar plasma. Conventional analysis of I-V curves as well as the elucidation form of the Electron Energy Distribution Function (EEDF) has become the source of calibration of plasma parameters in the reaction chamber. The high energy tail in the EEDF of electron temperature is seen to extend beyond 60 eV, at much larger distances from the ECR zone. This proves the suitability of the rector for plasma processing, since the electron energy is much beyond the threshold energy of bond breaking in most of the polymers. Nylon 6 is used as a representative candidate for surface processing in the presence of Ar, H2 + N2, and O2 plasma, treated at different locations inside the plasma chamber. In a typical case, the work of adhesion is seen to almost get doubled when treated with oxygen plasma. Morphology of the plasma treated surface and its hydrophilicity are discussed in view of the variation in electron density and electron temperature at these locations. Nano-protrusions arising from plasma treatment are set to be responsible for the hydrophobicity. Chemical sputtering and physical sputtering are seen to influence the surface morphology on account of sufficient electron energies and increased plasma potential.

  1. Stiffness control of a nylon twisted coiled actuator for use in mechatronic rehabilitation devices.

    Edmonds, Brandon P R; Trejos, Ana Luisa

    2017-07-01

    Mechatronic rehabilitation devices, especially wearables, have been researched extensively and proven to be promising additions to physical therapy, but most designs utilize traditional actuators providing unnatural, robot-like movements. Therefore, many researchers have focused on the development of actuators that mimic biological properties to provide patients with improved results, safety, and comfort. Recently, a twisted-coiled actuator (TCA) made from nylon thread has been found to possess many of these important properties when heated, such as variable stiffness, flexibility, and high power density. So far, TCAs have been characterized in controlled environments to define their fundamental properties under simple loading configurations. However, for an actuator like this to be implemented in a biomimetic design such as an exoskeleton, it needs to be characterized and controlled as a biological muscle. One major control law that natural muscles exhibit is stiffness control, allowing humans to passively avoid injury from external forces, or move the limbs in a controlled or high impact motion. This type of control is created by the antagonistic muscle arrangement. In this paper, an antagonistic apparatus was developed to model the TCAs from a biological standpoint, the stiffness was characterized with respect to the TCA temperature, and a fully functional stiffness and position controller was implemented with an incorporated TCA thermal model. The stiffness was found to have a linear relationship to the TCA temperatures (R 2 =0.95). The controller performed with a stiffness accuracy of 98.95% and a position accuracy of 92.7%. A final trial with varying continuous position input and varying stepped stiffness input exhibited position control with R 2 =0.9638.

  2. EFFICACY OF HYOSCINE BUTYL BROMIDE SUPPOSITORY FOR POSTOPERATIVE PAIN RELIEF

    Soniya C. Alphonse

    2017-07-01

    Full Text Available BACKGROUND Caesarean Section is on the rise all over the world. Women undergoing Caesarean section often wish to be awake post operatively and to avoid excessive medications affecting interactions with the new born infant. Multimodal pain therapy has been advocated for postoperative pain management after caesarean section. MATERIALS AND METHODS The study is a prospective randomized controlled study conducted at a tertiary care hospital to study the effect of Hyoscine Butyl Bromide Suppositories for postoperative analgesia following elective repeat caesarean section. The study included sixty patients divided into two groups- Group1 (study group were given Hyoscine Butyl Bromide Suppository (10 mg along with Injection. Tramadol 50 mg IM and Group II (control group were given Injection Tramadol IM only at the end of surgery. Pain score of the patient assessed at 1 hr, 2 hrs, 6hrs and 24 hrs post operatively. The total no of doses of injection tramadol needed in 24 hrs and the interval between 1st and 2nd dose of tramadol was also noted. The adverse effects of the drug and additional advantages of the drug if any were also assessed. RESULTS There was no statistically significant difference in pain score during the assessment intervals between the two groups. There was no difference in the number of doses of tramadol needed in the first 24 hrs. The mean interval between the 1st and 2nd dose of tramadol was found to be 7.6538 hours for group 1 patients and 6.9130 for group patients which was found to be statistically significant. There was no statistically significant side effects/ additional advantages for the drugs. CONCLUSION Concurrent administration of Hyoscine Butyl Bromide Suppository (10 mg and injection Tramadol 50 mg IM offers a longer postoperative analgesia without any increased adverse effects.

  3. Biological fate of butylated hydroxytoluene (BHT) in rats, (2)

    Nakagawa, Yoshio; Ikawa, Mieko; Hiraga, Kogo

    1976-01-01

    The fate of butylated hydroxytoluene (BHT) in hepatocytes was examined. 14 C-labelled BHT was administered once orally to rats, and the fractionation of hepatocytes was made in course of time to detect the subcellular distribution of radioactivity. The BHT incorporation into livers reached the maximum 6 hours after the administration. Most of the radioactivity was localized in the supernatant fraction at the beginning of the administration, but it decreased gradually, and the radioactivity in microsome fraction increased in time course. The radioactivity in the supernatant fraction and in serum assumed two forms; namely high molecular compound bound with protein and free low molecular compound. (Kobatake, H.)

  4. IRIS Toxicological Review of Ethylene Glycol Mono-Butyl ...

    EPA released the draft report, Toxicological Review for Ethylene Glycol Mono-Butyl Ether , that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the IRIS Assessment Development Process. Comments received from other Federal agencies and White House Offices are provided below with external peer review panel comments. EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessment of EGBE that will appear on the Integrated Risk Information System (IRIS) database.

  5. A study of butyl acetate synthesis. 4-reaction kinetics

    Álvaro Orjuela Londoño; Fernando Leiva Lenis; Luis Alejandro Boyacá Mendivelso; Gerardo Rodríguez Niño; Luis María Carballo Suárez

    2006-01-01

    This work was aimed at studying liquid-phase acetic acid and butyl alcohol esterification reaction (P atm =0.76 Bar),using an ion exchange resin (Lewatit K-2431) as catalyst. The effect of the absence of internal and external mass transport on catalyst particles was established in the research conditions used here. A set of assays to determine the effect of catalyst load (0.5%, 1%, 2% w/w) temperature (73°C, 80°C, 87°C) and molar ratio (1:2, 1:1, 2:1 acid/alcohol) on reaction rate was carrie...

  6. NMR analysis of t-butyl-catalyzed deuterium exchange at unactivated arene localities.

    Stack, Douglas E; Eastman, Rachel

    2016-10-01

    Regioselective labelling of arene rings via electrophilic exchange is often dictated by the electronic environment caused by substituents present on the aromatic system. Previously, we observed the presence of a t-butyl group, either covalently bond or added as an external reagent, could impart deuterium exchange to the unactivated, C1-position of estrone. Here, we provide nuclear magnetic resonance analysis of this exchange in a solvent system composed of 50:50 trifluoroacetic acid and D 2 O with either 2-t-butylestrone or estrone in the presence of t-butyl alcohol has shed insights into the mechanism of this t-butyl-catalyzed exchange. Fast exchange of the t-butyl group concurrent with the gradual reduction of the H1 proton signal in both systems suggest a mechanism involving ipso attack of the t-butyl position by deuterium. The reversible addition/elimination of the t-butyl group activates the H1 proton towards exchange by a mechanism of t-butyl incorporation, H1 activation and exchange, followed by eventual t-butyl elimination. Density functional calculations are consistent with the observation of fast t-butyl exchange concurrent with slower H1 exchange. The σ-complex resulting from ipso attack of deuterium at the t-butyl carbon was 6.6 kcal/mol lower in energy than that of the σ-complex resulting from deuterium attack at C1. A better understanding of the t-butyl-catalyzed exchange could help in the design of labelling recipes for other phenolic metabolites. Copyright © 2016 The Authors. Journal of Labelled Compounds and Radiopharmaceuticals published by John Wiley & Sons, Ltd.

  7. From zero to hero - production of bio-based nylon from renewable resources using engineered Corynebacterium glutamicum.

    Kind, Stefanie; Neubauer, Steffi; Becker, Judith; Yamamoto, Motonori; Völkert, Martin; Abendroth, Gregory von; Zelder, Oskar; Wittmann, Christoph

    2014-09-01

    Polyamides are important industrial polymers. Currently, they are produced exclusively from petrochemical monomers. Herein, we report the production of a novel bio-nylon, PA5.10 through an integration of biological and chemical approaches. First, systems metabolic engineering of Corynebacterium glutamicum was used to create an effective microbial cell factory for the production of diaminopentane as the polymer building block. In this way, a hyper-producer, with a high diaminopentane yield of 41% in shake flask culture, was generated. Subsequent fed-batch production of C. glutamicum DAP-16 allowed a molar yield of 50%, a productivity of 2.2gL(-1)h(-1), and a final titer of 88gL(-1). The streamlined producer accumulated diaminopentane without generating any by-products. Solvent extraction from alkalized broth and two-step distillation provided highly pure diaminopentane (99.8%), which was then directly accessible for poly-condensation. Chemical polymerization with sebacic acid, a ten-carbon dicarboxylic acid derived from castor plant oil, yielded the bio-nylon, PA5.10. In pure form and reinforced with glass fibers, the novel 100% bio-polyamide achieved an excellent melting temperature and the mechanical strength of the well-established petrochemical polymers, PA6 and PA6.6. It even outperformed the oil-based products in terms of having a 6% lower density. It thus holds high promise for applications in energy-friendly transportation. The demonstration of a novel route for generation of bio-based nylon from renewable sources opens the way to production of sustainable bio-polymers with enhanced material properties and represents a milestone in industrial production. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Caracterización y estudio de las propiedades térmicas de una poliamida impar (nylon 3

    Ángel T. Pérez Rodríguez

    2010-01-01

    Full Text Available El trabajo se centró en la caracterización y el estudio de las propiedades térmicas de una poliamida impar, el nylon 3, debido a su potencial aplicación como material con propiedades eléctricas activas. La poli-B-alanina o nylon 3 (-NH -CH2 -CH2 -CO-n, es un polímero cristalino que se caracteriza por tener una elevada densidad de grupos amida y, por tanto, de puentes de hidrógeno. Su principal atractivo en el campo de la ferroelectricidad está motivado por el momento dipolar asociado a los grupos amida. El nylon 3 utilizado fue obtenido por transferencia de hidrógeno a partir de acrilamida. Las fracciones soluble e insoluble en agua se han separado por extracciones repetidas con agua caliente. Para nuestro trabajo se usó exclusivamente la fracción insoluble. La caracterización se llevó a cabo mediante viscosimetría capilar y espectroscopía IR y RMN. Para el análisis térmico se utilizaron la calorimetría diferencial de barrido y el análisis termogravimétrico en atmósfera inerte. Nuestro objetivo ha sido estudiar las condiciones necesarias para obtener películas manipulables que permitieran la evaluación de la respuesta ferroeléctrica. Como resultados cabe destacar que los filmes obtenidos son poco manipulables debido a la baja flexibilidad que poseen.

  9. Thermodynamic properties of 1-butyl-3-methylpyridinium tetrafluoroborate

    Safarov, Javid; Kul, Ismail; El-Awady, Waleed A.; Shahverdiyev, Astan; Hassel, Egon

    2011-01-01

    Highlights: → (p, ρ, T) data of 1-butyl-3-methylpyridinium tetrafluoroborate are estimated. → The measurements were carried out with a vibration-tube densimeter. → The thermomechanical coefficients were calculated. - Abstract: Pressure, density, temperature (p, ρ, T) data of 1-butyl-3-methylpyridinium tetrafluoroborate [C4mpyr][BF 4 ] at T = (283.15 to 393.15) K and pressures up to p = 100 MPa are reported with an estimated experimental relative combined standard uncertainty of Δρ/ρ = ±(0.01 to 0.08)% in density. The measurements were carried out with a newly constructed Anton-Paar DMA HPM vibration-tube densimeter. The system was calibrated using double-distilled water, methanol, toluene and aqueous NaCl solutions. An empirical equation of state for fitting of the (p, ρ, T) data of [C4mpyr][BF 4 ] has been developed as a function of pressure and temperature to calculate the thermal properties of the ionic liquid (IL), such as isothermal compressibility, isobaric thermal expansibility, differences in isobaric and isochoric heat capacities, thermal pressure coefficient and internal pressure. Internal pressure and the temperature coefficient of internal pressure data were used to make conclusions on the molecular characteristics of the IL.

  10. Thermophysical properties of 1-butyl-4-methylpyridinium tetrafluoroborate

    Safarov, Javid; Kul, Ismail; El-Awady, Waleed A.; Nocke, Jürgen; Shahverdiyev, Astan; Hassel, Egon

    2012-01-01

    Highlights: ► (p, ρ, T) data of 1-butyl-4-methylpyridinium tetrafluoroborate are estimated. ► The measurements were carried out with a vibration-tube densimeter. ► The thermomechanical coefficients were calculated. - Abstract: Thermophysical properties, {(p, ρ, T) at T = (283.15 to 393.15) K, pressures up to p = 100 MPa, and viscosity at T = (283.15 to 373.15) K and p = 0.101 MPa}, of 1-butyl-4-methylpyridinium tetrafluoroborate [b4mpy][BF 4 ] are reported. The measurements were carried out with a recently constructed Anton-Paar DMA HPM vibration-tube densimeter and a fully automated SVM 3000 Anton-Paar rotational Stabinger viscometer. The vibration-tube densimeter was calibrated using double-distilled water, methanol, toluene, and aqueous NaCl solutions. An empirical equation of state for fitting of the (p, ρ, T) data of [b4mpy][BF 4 ] has been developed as a function of pressure and temperature to calculate the thermal properties of the ionic liquid (IL), such as isothermal compressibility, isobaric thermal expansibility, differences in isobaric and isochoric heat capacities, thermal pressure coefficient, and internal pressure. Internal pressure and the temperature coefficient of internal pressure data were used to make conclusions on the molecular characteristics of the IL.

  11. Kinetic investigations of emulsion- and solvent-mediated radiation induced graft copolymerization of glycidyl methacrylate onto nylon-6 fibres

    Teo Ming Ting; Paveswari Sithambaranathan

    2017-01-01

    Kinetic behaviour of graft copolymerisation of glycidyl methacrylate onto nylon-6 fibres in solvent- and emulsion- media was investigated. The order for the dependence of the initial rate of grafting on the monomer concentration for solvent and emulsion grafting systems were found to be 1.65 and 1.57, respectively. The order of dependence of the initial rate of grafting on the absorbed dose was found to be 1.55 for solvent and 0.62 emulsion grafting systems. The results showed that grafting in both systems is controlled by diffusion mechanism and the degree of grafting can be effectively tuned by variation of the grafting parameters. (author)

  12. cis,cis-Muconic acid: separation and catalysis to bio-adipic acid for nylon-6,6 polymerization

    Vardon, Derek R.; Rorrer, Nicholas A.; Salvachúa, Davinia; Settle, Amy E.; Johnson, Christopher W.; Menart, Martin J.; Cleveland, Nicholas S.; Ciesielski, Peter N.; Steirer, K. Xerxes; Dorgan, John R.; Beckham, Gregg T.

    2016-01-01

    cis,cis-Muconic acid is a polyunsaturated dicarboxylic acid that can be produced renewably via the biological conversion of sugars and lignin-derived aromatic compounds. Subsequently, muconic acid can be catalytically converted to adipic acid -- the most commercially significant dicarboxylic acid manufactured from petroleum. Nylon-6,6 is the major industrial application for adipic acid, consuming 85% of market demand; however, high purity adipic acid (99.8%) is required for polymer synthesis. As such, process technologies are needed to effectively separate and catalytically transform biologically derived muconic acid to adipic acid in high purity over stable catalytic materials. To that end, this study: (1) demonstrates bioreactor production of muconate at 34.5 g L-1 in an engineered strain of Pseudomonas putida KT2440, (2) examines the staged recovery of muconic acid from culture media, (3) screens platinum group metals (e.g., Pd, Pt, Rh, Ru) for activity and leaching stability on activated carbon (AC) and silica supports, (4) evaluates the time-on-stream performance of Rh/AC in a trickle bed reactor, and (5) demonstrates the polymerization of bio-adipic acid to nylon-6,6. Separation experiments confirmed AC effectively removed broth color compounds, but subsequent pH/temperature shift crystallization resulted in significant levels of Na, P, K, S and N in the crystallized product. Ethanol dissolution of muconic acid precipitated bulk salts, achieving a purity of 99.8%. Batch catalysis screening reactions determined that Rh and Pd were both highly active compared to Pt and Ru, but Pd leached significantly (1-9%) from both AC and silica supports. Testing of Rh/AC in a continuous trickle bed reactor for 100 h confirmed stable performance after 24 h, although organic adsorption resulted in reduced steady-state activity. Lastly, polymerization of bio-adipic acid with hexamethyldiamine produced nylon-6,6 with comparable properties to its petrochemical counterpart

  13. Synthesis of 4-tert-butyl-1,1-dimethylindan and 7-tert-Butyl-3,3-dimethyl-1-indanone and a comparison of isomers

    Eisenbraun, E.J.; Harms, W.M.; Paraniswamy, V.A.; Chen, H.H.; Porcaro, P.J.; Wood, T.F.; Chien, M.

    1982-01-01

    4-tert-Butyl-1,1-dimethylindan was synthesized to help establish the identity of products (5- and 6-tert-butyl-1,1-dimethylindan as minor and major products, respectively) from the sulfuric acid catalyzed condensation of tert-butylbenzene and isoprene. NMR ( 1 H and 13 C) studies of these hydrocarbons and their corresponding indanones, obtained through chromic acid oxidation, provided structural proof. Gated decoupling experiments were crucial to complete assignment

  14. Recovering/recycling of butyl and halogenated butyl rubber via ionizing radiation; Recuperacao/reciclagem de compostos de borrachas butilica e halobutilica por meio de radiacao ionizante

    Martin, Sandra Regina Scagliusi

    2013-07-01

    Polymeric materials (plastics and rubbers) attain a continuous and raising proportion of urban and industrial scraps discarded in landfills; their impact on environment are more and more concerning. The implementation of new technologies in order to reduce impacts of plastic waste on the environment, at an effective cost, proved to be a great problem, due to inherent complexity for polymers re-using. Ionizing radiation is capable to modify structure and properties of polymeric material. Butyl and halobutyl rubbers have been used within a comprehensive scale, applications such as tires spare parts and diverse artifacts. The major high energy photon effect, as gamma-rays in butyl and halo butyl rubbers consists in free-radicals generation along changes in mechanical properties.This work aims to the development of controlled degradation processes (devulcanization) of butyl and halo butyl (chlorine and bromine) rubbers, in order to characterize their availability for transformation and modification of properties. Experimental results obtained showed that butyl and halobutyl rubbers,irradiated at 25 kGy and further sheared, are able to be used as an initial point for mixtures with pristine. (author)

  15. Synthesis of Highly Porous Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) Asymmetric Membranes

    Xie, Yihui; Moreno Chaparro, Nicolas; Calo, Victor M.; Cheng, Hong; Hong, Pei-Ying; Sougrat, Rachid; Behzad, Ali Reza; Tayouo Djinsu, Russell; Nunes, Suzana Pereira

    2016-01-01

    For the first time, self-assembly and non-solvent induced phase separation was applied to polysulfone-based linear block copolymers, reaching mechanical stability much higher than other block copolymers membranes used in this method, which were mainly based on polystyrene blocks. Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) (PtBA30k-b-PSU14k-b-PtBA30k) with a low polydispersity of 1.4 was synthesized by combining step-growth condensation and RAFT polymerization. Various advanced electron microscopies revealed that PtBA30k-b-PSU14k-b-PtBA30k assembles into worm-like cylindrical micelles in DMAc and adopts a “flower-like” arrangement with the PSU central block forming the shell. Computational modeling described the mechanism of micelle formation and morphological transition. Asymmetric nanostructured membranes were obtained with a highly porous interconnected skin layer and a sublayer with finger-like macrovoids. Ultrafiltration tests confirmed a water permeance of 555 L m-2 h-1 bar-1 with molecular weight cut-off of 28 kg/mol. PtBA segments on the membrane surface were then hydrolyzed and complexed with metals, leading to cross-linking and enhancement of antibacterial capability.

  16. Levels of synthetic antioxidants (ethoxyquin, butylated hydroxytoluene and butylated hydroxyanisole) in fish feed and commercially farmed fish.

    Lundebye, A-K; Hove, H; Måge, A; Bohne, V J B; Hamre, K

    2010-12-01

    Several synthetic antioxidants are authorized for use as feed additives in the European Union. Ethoxyquin (EQ) and butylated hydroxytoluene (BHT) are generally added to fish meal and fish oil, respectively, to limit lipid oxidation. The study was conducted to examine the concentrations of EQ, BHT and butylated hydroxyanisole (BHA) in several commercially important species of farmed fish, namely Atlantic salmon, halibut and cod and rainbow trout, as well as concentrations in fish feed. The highest levels of BHT, EQ and BHA were found in farmed Atlantic salmon fillets, and were 7.60, 0.17 and 0.07 mg kg(-1), respectively. The lowest concentrations of the synthetic antioxidants found were in cod. The concentration of the oxidation product ethoxyquin dimer (EQDM) was more than ten-fold higher than the concentration of parent EQ in Atlantic salmon halibut and rainbow trout, whereas this dimer was not detected in cod fillets. The theoretical consumer exposure to the synthetic antioxidants EQ, BHA and BHT from the consumption of farmed fish was calculated. The contribution of EQ from a single portion (300 g) of skinned fillets of the different species of farmed fish would contribute at most 15% of the acceptable daily intake (ADI) for a 60 kg adult. The consumption of farmed fish would not contribute measurably to the intake of BHA; however, a 300 g portion of farmed Atlantic salmon would contribute up to 75% of the ADI for BHT.

  17. Synthesis of Highly Porous Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) Asymmetric Membranes

    Xie, Yihui

    2016-03-24

    For the first time, self-assembly and non-solvent induced phase separation was applied to polysulfone-based linear block copolymers, reaching mechanical stability much higher than other block copolymers membranes used in this method, which were mainly based on polystyrene blocks. Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) (PtBA30k-b-PSU14k-b-PtBA30k) with a low polydispersity of 1.4 was synthesized by combining step-growth condensation and RAFT polymerization. Various advanced electron microscopies revealed that PtBA30k-b-PSU14k-b-PtBA30k assembles into worm-like cylindrical micelles in DMAc and adopts a “flower-like” arrangement with the PSU central block forming the shell. Computational modeling described the mechanism of micelle formation and morphological transition. Asymmetric nanostructured membranes were obtained with a highly porous interconnected skin layer and a sublayer with finger-like macrovoids. Ultrafiltration tests confirmed a water permeance of 555 L m-2 h-1 bar-1 with molecular weight cut-off of 28 kg/mol. PtBA segments on the membrane surface were then hydrolyzed and complexed with metals, leading to cross-linking and enhancement of antibacterial capability.

  18. Impact of di-n-butyl phthalate on reproductive system development in European pikeperch (Sander lucioperca

    Sylwia Jarmołowicz

    2013-01-01

    Full Text Available Phthalic acid, di-n-butyl ester known as di-n-butyl phthalate, is an organic chemical compound that belongs to the group of endocrine disruptor compounds that have a documented negative impact on mammalian endocrine systems. Di-n-butyl phthalate is used widely as a plasticizer in the manufacture of artificial materials, which is why it is found in all types of environmental samples including those from water basins. The aim of the study was to describe the impact of di-n-butyl phthalate on the development of the reproductive system of European pikeperch (Sander lucioperca during the sex differentiation period (age 61–96 days post hatch. A total of 240 fish were divided into 6 groups (40 fish per tank. Treatments consisted of a control group (0 g di-n-butyl phthalate·kg-1 feed and five trial groups with 0.125, 0.25, 0.5, 1, and 2 g di-n-butyl phthalate·kg-1 feed, respectively. Histological changes of the fish gonads, sex ratio, survival and growth of fish were evaluated. Di-n-butyl phthalate seriously disturbed sex differentiation process of pikeperch. Histopathological analyses revealed that the administration of 2 g di-n-butyl phthalate·kg-1 significantly affected the sex ratio. The feminization process (intersex gonads at concentrations of 1 g and 2 g di-n-butyl phthalate·kg-1 were observed. All analyzed concentrations delayed testicular development. Phthalate did not have a significant impact on the survival or growth rates of the pikeperch. This is the first report of disruption sex differentiation processes in fish by di-n-butyl phthalate.

  19. Processing and characterization of a carbon black-filled electrically conductive Nylon-12 nanocomposite produced by selective laser sintering

    Athreya, Siddharth Ram; Kalaitzidou, Kyriaki; Das, Suman

    2010-01-01

    Selective laser sintering (SLS), a layered manufacturing technique was explored to process an electrically conductive polymer nanocomposite made of Nylon-12 reinforced with 4 wt% of carbon black. SLS process parameters were optimized in order to maximize the flexural modulus. The porosity and morphology were studied using optical microscopy and scanning electron microscopy (SEM). The crystalline state was characterized using differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The electrical conductivity was determined using the four probe technique. Results indicate that carbon black-filled Nylon-12 nanocomposites can be successfully made by SLS. Maximum flexural modulus values of 1750 MPa and 1450 MPa were achieved for the neat polymer and the nanocomposite, respectively. A reduction in the flexural modulus of the nanocomposite is likely due to the formation of a segregated structure in the nanocomposite and a weak polymer-filler interface. The optimized neat polymer and the nanocomposites had average densities of around 97% and 96% relative to full density, respectively. The electrical conductivity of the nanocomposite was approximately 1 x 10 -4 S/cm, which is five orders of magnitude higher than that of the neat polymer processed by SLS, and indicates that the onset of percolation behavior occurs below the 4 wt% loading of carbon black.

  20. [Oligonucleotide derivatives in the nucleic acid hybridization analysis. I. Covalent immobilization of oligonucleotide probes onto the nylon].

    Dmitrienko, E V; Pyshnaia, I A; Pyshnyĭ, D V

    2010-01-01

    The features of UV-induced immobilization of oligonucleotides on a nylon membranes and the effectiveness of enzymatic labeling of immobilized probes at heterophase detection of nucleic acids are studied. Short terminal oligothymidilate (up to 10 nt) sequences are suggested to attach to the probe via a flexible ethylene glycol based linker. The presence of such fragment enhances the intensity of immobilization and reduces UV-dependent degradation of the targeted (sequence-specific) part of the probe by reducing the dose needed for the immobilization of DNA. The optimum dose of UV-irradiation is determined to be ~0.4 J/cm(2) at the wavelength 254 nm. This dose provides high level of hybridization signal for immobilized probes with various nucleotide composition of the sequence specific moiety. The amide groups of the polyamide are shown to play the key role in the photoinduced immobilization of nucleic acids, whereas the primary amino groups in the structure of PA is not the center responsible for the covalent binding of DNA by UV-irradiation, as previously believed. Various additives in the soaking solution during the membrane of UV-dependent immobilization of probes are shown to influence its effectiveness. The use of alternative to UV-irradiation system of radical generation are shown to provide the immobilization of oligonucleotides onto the nylon membrane.

  1. STRUCTURAL PHASE TRANSITION OF ALIPHATIC NYLONS VIEWED FROM THE WAXD/SAXS AND VIBRATIONAL SPECTRAL MEASUREMENTS AND MOLECULAR DYNAMICS CALCULATION

    Kohji Tashiro

    2007-01-01

    The crystalline phase transition of aliphatic nylon 10/10 has been investigated on the basis of the simultaneous measurement of wide-angle and small-angle X-ray scatterings, the infrared spectral measurement and the molecular dynamics calculation. An interpretation of infrared spectra taken for a series of nylon samples and the corresponding model compounds was successfully made, allowing us to assign the infrared bands of the planar-zigzag methylene segments reasonably. As a result the methylene segmental parts of molecular chains were found to experience an order-to-disorder transition in the Brill transition region, where the intermolecular hydrogen bonds are kept alive although the bond strength becomes weaker at higher temperature. The small-angle X-ray scattering data revealed a slight change in lamellar stacking mode in the transition region. The crystal structure has been found to change more remarkably in the temperature region immediately below the melting point, where the conformationally disordered chains experienced drastic rotational and translational motions without any constraints by hydrogen bonds, and the lamellar thickness increased largely along the chain axis. These experimental results were reasonably reproduced by the molecular dynamics calculation performed at the various temperatures.

  2. Extraction of Micro- and Nano-Fibrils from Nylon 6/Polypropylene Grafted with Maleic Anhydride/Polypropylene Blended Films

    E. Bagheban Kochak

    2013-01-01

    Full Text Available Atechnical feasibility study has been conducted on production of nano- and micro-fibrils from nylon 6/polypropylene grafted with maleic anhydride/polypropylene blended films. Fibrils are prepared in four consecutive steps.In the first step the polymers melt blended in an extruder with and without compatibilizers to produce chips; in the second step films are extruded from polymer blends chips, in the third step films are cold drawn with different draw ratios at room temperature and in the forth step fibrils are extracted by Soxhlet extraction with formic acid as solvent for nylon 6.  The films and fibrils were examined by scanning electron microscope and FTIR spectroscopy. It is found that the polypropylene dispersed phase deforms and coalesces into elongated fibrils during drawing  operation. The  fibrils’ diameters in the blends containing compatibilizer are more uniform and are smaller than those from films without compatibilizers. The thinnest polypropylene fibril observed has a diameter around 300 nm with the aspect ratio above 150. The stress-elongation curves show three distinctive regions, elastic, yield and hardening-leading to breakage. The elastic region is short and follows by necking and yield, i.e., elongation without increase in load. The hardening region is accompanied by the increase in the slope. The deformations of the polypropylene particles are noticed during the last regions of the extension; the fibril deformations seem to be more severe during breakage.

  3. Comparison of gaseous oxidized Hg measured by KCl-coated denuders, and nylon and cation exchange membranes.

    Huang, Jiaoyan; Miller, Matthieu B; Weiss-Penzias, Peter; Gustin, Mae Sexauer

    2013-07-02

    The chemical compounds that make up gaseous oxidized mercury (GOM) in the atmosphere, and the reactions responsible for their formation, are not well understood. The limitations and uncertainties associated with the current method applied to measure these compounds, the KCl-coated denuder, are not known due to lack of calibration and testing. This study systematically compared the uptake of specific GOM compounds by KCl-coated denuders with that collected using nylon and cation exchange membranes in the laboratory and field. In addition, a new method for identifying different GOM compounds using thermal desorption is presented. Different GOM compounds (HgCl2, HgBr2, and HgO) were found to have different affinities for the denuder surface and the denuder underestimated each of these compounds. Membranes measured 1.3 to 3.7 times higher GOM than denuders in laboratory and field experiments. Cation exchange membranes had the highest collection efficiency. Thermodesorption profiles for the release of GOM compounds from the nylon membrane were different for HgO versus HgBr2 and HgCl2. Application of the new field method for collection and identification of GOM compounds demonstrated these vary as a function of location and time of year. Understanding the chemistry of GOM across space and time has important implications for those developing policy regarding this environmental contaminant.

  4. Modelling the Peak Elongation of Nylon6 and Fe Powder Based Composite Wire for FDM Feedstock Filament

    Garg, Harish Kumar; Singh, Rupinder

    2017-10-01

    In the present work, to increase the application domain of fused deposition modelling (FDM) process, Nylon6-Fe powder based composite wire has been prepared as feed stock filament. Further for smooth functioning of feed stock filament without any change in the hardware and software of the commercial FDM setup, the mechanical properties of the newly prepared composite wire must be comparable/at par to the existing material i.e. ABS, P-430. So, keeping this in consideration; an effort has been made to model the peak elongation of in house developed feedstock filament comprising of Nylon6 and Fe powder (prepared on single screw extrusion process) for commercial FDM setup. The input parameters of single screw extruder (namely: barrel temperature, temperature of the die, speed of the screw, speed of the winding machine) and rheological property of material (melt flow index) has been modelled with peak elongation as the output by using response surface methodology. For validation of model the result of peak elongation obtained from the model equation the comparison was made with the results of actual experimentation which shows the variation of ±1 % only.

  5. The influence of carrier gas flow rate in inverse gas chromatography on the estimation of water vapor adsorption on Nylon-6 micro fiber

    丸井, 正樹; 山本, 直子; 牛腸, ヒロミ; マルイ, マサキ; ヤマモト, ナオコ; ゴチョウ, ヒロミ; MASAKI, MARUI; NAOKO, YAMAMOTO; HIROMI, GOCHO

    2002-01-01

    The adsorption behaviors of water vapor on Nylon-6 micro fiber are measured at 90℃ with inverse gas chromatography, of which the carrier gas flow rates are 10~40ml/min. The values of retention volume decrease when the peak area is on the increase. lt indicates that Nylon-6 micro fiber has strong adsorption of water vapor at low vapor pressure. The adsorption isotherm as a whole is found to be of BET II type with certain number of adsorption sites. The gas flow rate has no effect on the estima...

  6. Hyoscine-N-Butyl-Bromide-Induced Hypotension and Myocardial Ischemia

    Guan-Liang Chen

    2013-01-01

    Full Text Available Hyoscine N-butyl bromide, also known as scopolamine, is a type of antimuscarinic agent. This drug is associated with numerous common side effects, including abdominal fullness, constipation, urinary retention, blurred vision, skin flushing, tachycardia, decreased sweating, and salivation. The most unfavorable side effect is hemodynamic instability. In the present case, hypotension and acute myocardial infarction developed after intravenous hyoscine injection as a premedication therapy for colonoscopy. It was difficult to differentiate the cause-effect relationship between myocardial infarction and hypotension. Because both conditions were present under drug effects, we considered 2 possible diagnoses. One was coronary spasm with cardiogenic shock, and the other was myocardial ischemic sequela due to shock status. The latter diagnosis was confirmed after a series of examinations.

  7. Interaction of butylated hydroxyanisole with mitochondrial oxidative phosphorylation.

    Fusi, F; Sgaragli, G; Murphy, M P

    1992-03-17

    The antioxidant, butylated hydroxyanisole (BHA), has a number of effects on mitochondrial oxidative phosphorylation. In this study we apply the novel approach developed by Brand (Brand MD, Biochim Biophys Acta 1018: 128-133, 1990) to investigate the site of action of BHA on oxidative phosphorylation in rat liver mitochondria. Using this approach we show that BHA increases the proton leak through the mitochondrial inner membrane and that it also inhibits the delta p (proton motive force across the mitochondrial inner membrane) generating system, but has no effect on the phosphorylation system. This demonstrates that compounds having pleiotypic effects on mitochondrial oxidative phosphorylation in vitro can be analysed and their many effects distinguished. This approach is of general use in analysing many other compounds of pharmacological interest which interact with mitochondria. The implications of these results for the mechanism of interaction of BHA with mitochondrial oxidative phosphorylation are discussed.

  8. A study of butyl acetate synthesis. 4-reaction kinetics

    Álvaro Orjuela Londoño

    2006-05-01

    Full Text Available This work was aimed at studying liquid-phase acetic acid and butyl alcohol esterification reaction (P atm =0.76 Bar,using an ion exchange resin (Lewatit K-2431 as catalyst. The effect of the absence of internal and external mass transport on catalyst particles was established in the research conditions used here. A set of assays to determine the effect of catalyst load (0.5%, 1%, 2% w/w temperature (73°C, 80°C, 87°C and molar ratio (1:2, 1:1, 2:1 acid/alcohol on reaction rate was carried out and both LHHW and pseudo-homogeneous kinetic expressions were obtained, these being in good agreement with the experimental data.

  9. Gamma-radiation effect on thermal ageing of butyl rubber compounds

    Scagliusi, Sandra R.; Cardoso, Elizabeth C.L.; Lugao, Ademar B.

    2015-01-01

    Butyl rubber has a comprehensive use in sealing systems, especially in tires inner tubes, due to their low permeability to gases. So, it is required that butyl rubber compounds show a better performance, more and more. Butyl rubber is provided with excellent mechanical properties and oxidation resistance. Besides showing these properties, radiation exposures impart modifications in physical-chemical and morphological properties on butyl rubber materials. When exposed to gamma-radiation, rubbers suffer changes in their mechanical and physical properties, caused by material degradation. The major radiation effect in butyl rubbers is chain scission; besides, ageing promotes too the same effect with further build-up of free radicals. This work aims to the study of gamma-radiation in physical-chemical properties of butyl rubber subjected to thermal ageing. Doses used herein were: 25 kGy, 50 kGy, 100 kGy, 150 kGy and 200 KGy. Samples were evaluated before and after ageing according to traditional essays, such as: hardness, tensile strength and elongation at break. From accomplished assessments it is possible to affirm that at doses higher than 50 kGy it was observed a sharp decreasing in butyl rubber physical-chemical properties, before and after exposure to ageing. (author)

  10. Gamma-radiation effect on thermal ageing of butyl rubber compounds

    Scagliusi, Sandra R.; Cardoso, Elizabeth C.L.; Lugao, Ademar B., E-mail: srscagliusi@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Butyl rubber has a comprehensive use in sealing systems, especially in tires inner tubes, due to their low permeability to gases. So, it is required that butyl rubber compounds show a better performance, more and more. Butyl rubber is provided with excellent mechanical properties and oxidation resistance. Besides showing these properties, radiation exposures impart modifications in physical-chemical and morphological properties on butyl rubber materials. When exposed to gamma-radiation, rubbers suffer changes in their mechanical and physical properties, caused by material degradation. The major radiation effect in butyl rubbers is chain scission; besides, ageing promotes too the same effect with further build-up of free radicals. This work aims to the study of gamma-radiation in physical-chemical properties of butyl rubber subjected to thermal ageing. Doses used herein were: 25 kGy, 50 kGy, 100 kGy, 150 kGy and 200 KGy. Samples were evaluated before and after ageing according to traditional essays, such as: hardness, tensile strength and elongation at break. From accomplished assessments it is possible to affirm that at doses higher than 50 kGy it was observed a sharp decreasing in butyl rubber physical-chemical properties, before and after exposure to ageing. (author)

  11. Sorption of methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) to synthetic resins.

    Bi, Erping; Haderlein, Stefan B; Schmidt, Torsten C

    2005-10-01

    Methyl tert-butyl ether (MTBE) is a widely used gasoline oxygenate. Contamination of MTBE and its major degradation product tert-butyl alcohol (TBA) in groundwater and surface water has received great attention. However, sorption affinity and sorption mechanisms of MTBE and TBA to synthetic resins, which can be potentially used in removal of these contaminants from water, in passive sampling, or in enrichment of bacteria, have not been studied systemically. In this study, kinetic and equilibrium sorption experiments (single solute and binary mixtures) on four synthetic resins were conducted. The sorption affinity of the investigated sorbents for MTBE and TBA decreases in the order Ambersorb 563>Optipore L493>Amberlite XAD4>Amberlite XAD7, and all show higher sorption affinity for MTBE than for TBA. Binary experiments with o-xylene, a major compound of gasoline as co-contaminant, imply that all resins preferentially sorb o-xylene over MTBE or TBA, i.e., there is sorption competition. In the equilibrium aqueous concentration (Ceq) range (0.1-139.0 mg/L for MTBE, and 0.01-48.4 mg/L for TBA), experimental and modeling results as well as sorbent characteristics indicate that micropore filling and/or some other type of adsorption process (e.g., adsorption to specific sites of high sorption potential at low concentrations) rather than partitioning were the dominant sorption mechanisms. Optipore L493 has favourable sorption and desorption characteristics, and is a suitable sorbent, e.g., in bacteria enrichment or passive sampling for moderately polar compounds. However, for highly polar compounds such as TBA, Ambersorb 563 might be a better choice, especially in water treatment.

  12. 76 FR 77709 - Butyl acrylate-methacrylic acid-styrene polymer; Tolerance Exemption

    2011-12-14

    ...This regulation establishes an exemption from the requirement of a tolerance for residues of 2-Propenoic acid, 2-methyl-, polymer with butyl 2-propenoate and ethenylbenzene (CAS Reg. No. 25036-16-2); also known as butyl acrylate-methacrylic acid-styrene polymer when used as an inert ingredient in a pesticide chemical formulation. Momentive Performance Materials submitted a petition to EPA under the Federal Food, Drug, and Cosmetic Act (FFDCA), requesting an exemption from the requirement of a tolerance. This regulation eliminates the need to establish a maximum permissible level for residues of 2-Propenoic acid, 2-methyl-, polymer with butyl 2-propenoate and ethenylbenzene on food or feed commodities.

  13. Effects of a natural fire on a Kuenzler's hedgehog cactus (Echinocereus fendleri var. kuenzleri) and nylon hedgehog cactus (Echinocereus viridiflorus) population in Southeastern New Mexico

    Robert C. Sivinski

    2007-01-01

    During the summer of 1992, a natural wildfire burned 250 acres of juniper savanna on Rawhide Ridge in the Guadalupe Mountains of southeastern New Mexico. This fire burned through the center of a Kuenzler's hedgehog cactus population. This threatened cactus is locally sympatric with the more abundant nylon hedgehog cactus, which has similar growth form and stature...

  14. Influence of 1D and 2D Carbon Fillers and Their Functionalisation on Crystallisation and Thermomechanical Properties of Injection Moulded Nylon 6,6 Nanocomposites

    Fabiola Navarro-Pardo

    2014-01-01

    Full Text Available Carbon nanotubes (CNTs and graphene were used as reinforcing fillers in nylon 6,6 in order to obtain nanocomposites by using an injection moulding process. The two differently structured nanofillers were used in their pristine or reduced form, after oxidation treatment and after amino functionalisation. Three low nanofiller contents were employed. Crystallisation behaviour and perfection of nylon 6,6 crystals were determined by differential scanning calorimetry and wide angle X-ray diffraction, respectively. Crystallinity was slightly enhanced in most samples as the content of the nanofillers was increased. The dimensionality of the materials was found to provide different interfaces and therefore different features in the nylon 6,6 crystal growth resulting in improved crystal perfection. Dynamical, mechanical analysis showed the maximum increases provided by the two nanostructures correspond to the addition of 0.1 wt.% amino functionalised CNTs, enhancing in 30% the storage modulus and the incorporation of 0.5 wt.% of graphene oxide caused an increase of 44% in this property. The latter also provided better thermal stability when compared to pure nylon 6,6 under inert conditions. The superior properties of graphene nanocomposites were attributed to the larger surface area of the two-dimensional graphene compared to the one-dimensional CNTs.

  15. Follow-up study of workers in a nylon carpet yarn plant after remedial actions taken against a contaminated humidification system

    Pal, TM; Groothoff, JW; Post, D; de Monchy, JGR

    Objective: To investigate the effectiveness of remedial actions taken against a contaminated humidification system, after an outbreak of humidifier disease in a nylon carpet yam plant. Methods: Two and 6 years after modification, a follow-up investigation of a strati tied (age, smoking habits)

  16. Comparison of organic matter degradation in several feedstuffs in the rumen as determined with the nylon bag and gas production techniques

    Cone, John W.; Van Gelder, Antonie H.; Bachmann, Herwig; Hindle, Vincent A.

    2002-01-01

    Organic matter (OM) degradation of 21 feedstuffs was investigated with rumen fluid using a rumen in situ technique and a gas production technique. Fitting the nylon bag data to an exponential model showed that there was a high variation in the rate of OM degradation ranging from 1.7% h-1 for

  17. Use of the mobile nylon bag technique for determination of apparent ileal digestibilities of crude protein and amino acids in feedstuffs for pigs

    Steiner, T; Bornholdt, U; Sauer, W C

    2011-01-01

    /l at pH 2.0 and 37°C for 4 h. In the 28-day in vivo experiment, 15 nylon bags per pig and day were inserted through the duodenal cannula and collected through the PVTC cannula after passage through the small intestine. Coefficients of AID were calculated based on the disappearance of CP and AA from...

  18. Flocked nylon swabs versus RODAC plates for detection of multidrug-resistant organisms on environmental surfaces in intensive care units.

    Okamoto, K; Rhee, Y; Schoeny, M; Lolans, K; Cheng, J; Reddy, S; Weinstein, R A; Hayden, M K; Popovich, K J

    2018-01-01

    To compare two culture methods [nylon fiber flocked swabs with broth enrichment versus RODAC ('replicate organism detection and counting') plates] for recovery of multidrug-resistant organisms, 780 environmental surfaces in 63 rooms of patients on contact precautions in four intensive care units at one hospital were examined. Among sites that had at least one positive culture, swab culture with broth enrichment detected the target organisms more frequently than RODAC plates (37.5% vs 26.0%, P = 0.06). There was moderate agreement between the two methods (κ = 0.44) with agreement better for small or flat surfaces compared to large or irregular surfaces. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  19. High sensitivity two filter radon/thoron detectors with a wire or nylon screen as a second filter

    Whittlestone, S.; Zahorowski, W.; Wasiolek, P.

    1994-12-01

    A study is made of the use of wire and nylon screens as a second filter in two radon or thoron detectors. It is shown that acceptable detection efficiency is obtained at flow rates comparable to those used in detectors in which other types of filter are used. The main advantage of the screens is their very low flow impedance. Several designs of detector which exploit this feature are discussed. Details are given of the performance of three prototypes: a 32 L radon detector with a limit of detection of 0.0027 Bq m -3 and power consumption of 25 watts; and a portable thoron emanometer capable of detecting fluxes as low as 1 m Bq m -2 s -1 . The radon detectors are rugged and simple. They can operate with no routine maintenance and are suited to remote locations where only infrequent technical support is available. 14 refs., 2 tabs., 9 figs

  20. The Radiation Induced Graft Copolymerization of Methacrylic Acid to Nylon; Copolymerisation par greffe de l'acide methacrylique sur le nylon, provoquee par irradiation; Obluchenie vyzyvaet graft-kopolimerizats yu metakrilovoj kisloty v nejlone; Injerto del acido metacrilico en el nylon por copolimerizacion radioinducida

    Roberts, R; Thomas, J K

    1960-07-15

    The grafting of methacrylic acid to nylon by the preirradiation technique has been studied. The rate of grafting is appreciably larger than that of homopolymerization. No simple relation exists between reaction rate and total dose. The temperature dependence of the rate of grafting to the fibre, preirradiated in air, indicates that initiation of grafting is likely to take place by decomposition of peroxide groups formed on irradiation. Electrical resistance measurements on the irradiated fibre indicate that this has been reduced by a factor of 10. (author) [French] On a etudie le greffage de l'acide methacrylique sur du nylon par la technique de preirradiation. La vitesse du greffage est sensiblement plus grande que celle de l'homopolymerisation. Il n'existe pas de rapport simple entre la vitesse de reaction et la dose totale. Le fait que la vitesse du greffage sur la fibre, pre-irradiee a l'air, depend de la temperature, indique que l'amorcage de la greffe est susceptible d'etre provoque par la decomposition des groupements de peroxyde formes lors de l'irradiation. Les mesures de resistance electrique effectuees sur la fibre irradiee indiquent que cette resistance a ete reduite au dixieme de la valeur originale. (author) [Spanish] Al estudiar la copolimerizacio n de injerto del acido metacrilico en el nylon por el procedimiento de preirradiacion, los autores comprobaron que la velocidad de injerto es sensiblemente mas elevada que la de homopolimerizacion. No existe una relacion sencilla entre la velocidad de reaccion y la dosis total. La influencia de la temperatura sobre la velocidad de injerto en la fibra previamente irradiada en aire indica que el proceso se inicia por descomposicion de los grupos peroxido formados durante la irradiacion. Las mediciones efectuadas demuestran que la resistencia electrica de la fibra irradiada solo alcanza la decima parte de la correspondiente a la fibra no tratada. (author) [Russian] Bylo provedeno izuchenie prosachivaniya

  1. Study of mechanical properties and fracture mechanisms of synthetic fibers nylon-and-polyester type, used in engineering products

    Cardoso, Sergio Gomes

    2009-01-01

    Fibers are groups formed by molecular-chain-oriented filaments. Fibers play a fundamental role in human being's daily life and they can be found in several forms and geometries, such as filaments, yarns, beams, rope, fabric, composite, coatings, others. They are used in various segments such as civil, mechanical, electrical, electronics, military, naval, nautical, aviation, health, medicine, environment, communications, safety, space, others. Fibers are divided into two distinct classes: natural and chemical ones, which cover synthetic and man-made sub-classes. They can be produced from several materials, such as wool, cotton, rayon, flax, silk, rock, nylon, polyester, polyethylene, poly-propylene, aramid, glass, carbon, steel, ceramic, others. Globally, the participation of chemical fibers corresponds to approximately 59,9%, and the synthetic fiber polyester, the most used one, represents approximately 63% of the world market. Vital needs have led to the development of multi-function fibers and the focus has changed in the last 10 years with the use of nano technology for environmental responsibility and smart fibers. The study of mechanical properties and fracture mechanisms of fibers is of great relevance for characterization and understanding of causes as consequence of failures. For such reason, it was selected technical fabrics made of high performance synthetic fiber nylon-and-polyester type, used in engineered products such as tires, belts, hoses and pneumatic springs, which have been analyzed in each processing phase. Fiber samples were extracted after each processing phase to be analyzed, by traction destructive tests and scanning electron microscopy. The results of analysis of mechanical properties showed loss of resistance to temperature and multi axial stress during fiber processing phase. Through microscopy tests, it was possible to find contamination, surface stains, plastic deformations, scaling, variations in the fracture faces of the filaments and

  2. A new analytical application of nylon-induced room-temperature phosphorescence: Determination of thiabendazole in water samples

    Correa, R.A. [Departamento de Quimica Analitica, Facultad de Ciencias Bioquimicas y Farmaceuticas, Universidad Nacional de Rosario, Suipacha 531 (2000) Rosario (Argentina); Escandar, G.M. [Departamento de Quimica Analitica, Facultad de Ciencias Bioquimicas y Farmaceuticas, Universidad Nacional de Rosario, Suipacha 531 (2000) Rosario (Argentina)]. E-mail: gescanda@fbioyf.unr.edu.ar

    2006-06-30

    This paper discusses the first analytical determination of the widely used fungicide thiabendazole by nylon-induced phosphorimetry. Nylon was investigated as a novel solid-matrix for inducing room-temperature phosphorescence of thiabendazole, which was enhanced under the effect of external heavy-atom salts. Among the investigated salts, lead(II) acetate was the most effective in yielding a high phosphorescence signal. An additional enhancement of the phosphorescence emission was attained when the measurements were carried out under a nitrogen atmosphere. There was only a moderate increase in the presence of cyclodextrins. The room-temperature phosphorescence lifetimes of the adsorbed thiabendazole were measured under different working conditions and, in all cases, two decaying components were detected. On the basis of the obtained results, a very simple and sensitive phosphorimetric method for the determination of thiabendazole was established. The analytical figures of merit obtained under the best experimental conditions were: linear calibration range from 0.031 to 0.26 {mu}g ml{sup -1} (the lowest value corresponds to the quantitation limit), relative standard deviation, 2.4% (n = 5) at a level of 0.096 {mu}g ml{sup -1}, and limit of detection calculated according to 1995 IUPAC Recommendations equal to 0.010 {mu}g ml{sup -1} (0.03 ng/spot). The potential interference from common agrochemicals was also studied. The feasibility of determining thiabendazole in real samples was successfully evaluated through the analysis of spiked river, tap and mineral water samples.

  3. Effects of simulant mixed waste on EPDM and butyl rubber

    Nigrey, P.J.; Dickens, T.G.

    1998-01-01

    We have developed a Chemical Compatibility Testing Program for the evaluation of plastic packaging components which may be used in transporting mixed waste forms. In this program, we have screened 10 plastic materials in four liquid mixed waste simulants. These plastics were butadiene-acrylonitrile copolymer (Nitrile) rubber, cross-linked polyethylene, epi-chloro-hydrin rubber, ethylene-propylene (EPDM) rubber, fluorocarbons (Viton and Kel-F), poly-tetrafluoroethylene (Teflon), high-density polyethylene, isobutylene-isoprene copolymer (Butyl) rubber, polypropylene, and styrene-butadiene (SBR) rubber. The selected simulant mixed wastes were (1) an aqueous alkaline mixture of sodium nitrate and sodium nitrite; (2) a chlorinated hydrocarbon mixture; (3) a simulant liquid scintillation fluid; and (4) a mixture of ketones. The screening testing protocol involved exposing the respective materials to ∼3 kGy of gamma radiation followed by 14-day exposures to the waste simulants at 60 deg. C. The rubber materials or elastomers were tested using VTR measurements while the liner materials were tested using specific gravity as a metric. For these tests, screening criteria of ∼1 g/hr/m 2 for VTR and specific gravity change of 10% were used. Those materials that failed to meet these criteria were judged to have failed the screening tests and were excluded from the next phase of this experimental program. We have completed the comprehensive testing phase of liner materials in a simulant Hanford Tank waste consisting of an aqueous alkaline mixture of sodium nitrate and sodium nitrite. From the data analyses performed, we have identified the chloro-fluorocarbon Kel-F as having the greatest chemical durability after having been exposed to gamma radiation followed by exposure to the aqueous alkaline simulant mixed waste. The most striking observation from this study was the extremely poor performance of Teflon under these conditions. We have also completed the comprehensive

  4. Ethyl tertiary-butyl ether: a toxicological review.

    McGregor, Douglas

    2007-05-01

    A number of oxygenated compounds (oxygenates) are available for use in gasoline to reduce vehicle exhaust emissions, reduce the aromatic compound content, and avoid the use of organo-lead compounds, while maintaining high octane numbers. Ethyl tertiary-butyl ether (ETBE) is one such compound. The current use of ETBE in gasoline or petrol is modest but increasing, with consequently similar trends in the potential for human exposure. Inhalation is the most likely mode of exposure, with about 30% of inhaled ETBE being retained by the lungs and distributed around the body. Following cessation of exposure, the blood concentration of ETBE falls rapidly, largely as a result of its metabolism to tertiary-butyl alcohol (TBA) and acetaldehyde. TBA may be further metabolized, first to 2-methyl-1,2-propanediol and then to 2-hydroxyisobutyrate, the two dominant metabolites found in urine of volunteers and rats. The rapid oxidation of acetaldehyde suggests that its blood concentration is unlikely to rise above normal as a result of human exposure to sources of ETBE. Single-dose toxicity tests show that ETBE has low toxicity and is essentially nonirritant to eyes and skin; it did not cause sensitization in a maximization test in guinea pigs. Neurological effects have been observed only at very high exposure concentrations. There is evidence for an effect of ETBE on the kidney of rats. Increases in kidney weight were seen in both sexes, but protein droplet accumulation (with alpha(2u)-globulin involvement) and sustained increases in cell proliferation occurred only in males. In liver, centrilobular necrosis was induced in mice, but not rats, after exposure by inhalation, although this lesion was reported in some rats exposed to very high oral doses of ETBE. The proportion of liver cells engaged in S-phase DNA synthesis was increased in mice of both sexes exposed by inhalation. ETBE has no specific effects on reproduction, development, or genetic material. Carcinogenicity studies

  5. Preparation and characterization of emulsifier-free polyphenylsilsesquioxane-poly (styrene–butyl acrylate) hybrid particles

    Bai, Ruiqin; Qiu, Teng, E-mail: qiuteng@mail.buct.edu.cn; Han, Feng; He, Lifan; Li, Xiaoyu, E-mail: lixy@mail.buct.edu.cn

    2013-10-01

    The core–shell polyphenylsilsesquioxane-poly (styrene–butyl acrylate) hybrid latex paticles with polyphenylsilsesquioxane as core and poly (styrene–butyl acrylate) as shell were successfully synthesized by seeded emulsion polymerization using polyphenylsisesquioxane (PPSQ) latex particles as seeds. X-ray diffraction (XRD) indicated that the polyphenylsilsesquioxane (PPSQ) had ladder structure, and PPSQ had incorporated into the hybrid latex particles. Transmission electron microscopy (TEM) confirmed that the resultant hybrid latex particles had the core–shell structure. TEM and dynamic light scattering (DLS) analysis indicated that the polyphenylsisesquioxane latex particles and obtained core–shell hybrid latex particles were uniform and possessed narrow size distributions. X-ray photoelectron spectroscopy (XPS) analysis also indicated that the PPSQ core particles were enwrapped by the polymer shell. In addition, compared with pure poly (styrene–butyl acrylate) latex film, the polyphenylsilsesquioxane-poly (styrene–butyl acrylate) hybrid latex film exhibited lower water uptake, higher pencil hardness and better thermal stability.

  6. Inducing PLA/starch compatibility through butyl-etherification of waxy and high amylose starch

    Wokadala, OC

    2014-06-01

    Full Text Available In this study, waxy and high amylose starches were modified through butyl-etherification to facilitatecompatibility with polylactide (PLA). Fourier transform infrared spectroscopy, proton nuclear magneticresonance spectroscopy and wettability tests...

  7. A comparison of the effect of intranasal desmopressin and intramuscular hyoscine N-butyl bromide combination with intramuscular hyoscine N-butyl bromide alone in acute renal colic

    Abdol-Reza Kheirollahi

    2010-01-01

    Full Text Available Background: Patients with acute renal colic usually require immediate diagnosis and treatment. In this clinical trial analgesic effect of hyoscine N-butyl bromide and desmopressin combination in comparison with hyoscine N-butyl bromide alone in patients with acute renal colic induced by urinary stones was assessed. Methods: The study included 114 patients randomly allocated in two groups (A and B. Patients in group A received 20 mg intramuscular hyoscine N-butyl bromide at admission time and patients in group B received 20 μg of intranasal desmopressin in combination with 20 mg intramuscular hyoscine N-butyl bromide. A visual analogue scale (VAS; a 10-cm horizontal scale ranging from "zero or no pain" to "10 or unbearable pain" was hired to assess the patients′ pain severity at baseline, 30 and 60 minutes after the treatments. Results: On admission, the pain level was similar in both groups (group A: 8.95 ± 0.11 and group B: 8.95 ± 0.12. In group A, the mean of pain level showed a decrease after 30 minutes (group A: 7.26 ± 0.25 and group B: 5.95 ± 0.28 but further decreasing did not occur; however in group B, the pain consistently decreased and the mean after 60 minutes was significantly decreased (group A: 6.80 ± 0.31 and group B: 3.71 ± 0.31. No side effects were detected in this study. Conclusions: The combination of hyoscine N-butyl bromide and desmopressin is more effective than hyoscine N-butyl bromide alone in patients with renal colic. Further studies are recommended to validate these findings and compare the different doses of desmopressin.

  8. Recycling of Gamma Irradiated Inner Tubes in Butyl Based Rubber Compound

    Karaagac, B.

    2006-01-01

    Crosslinked elastomeric materials, such as tyres are of great challenge concerning the environmental and ecological reasons. Ionizing radiation seems to offer unique opportunities to tackle the problem of recycling of polymers and rubbers on account of its ability to cause chain scission and/or cross-linking of polymeric materials. There is only limited amount of work reported on the irradiation-induced degradation of rubbers. Unlike the majority of the elastomers with high levels of unsaturation, butyl rubber exhibits significant degradation by ionizing radiation action. In this study, recycling of gamma irradiated inner tubes made of butyl rubber in butyl based rubber compounds was studied. Used inner tubes were irradiated with gamma rays in air at 100 and 120 kGy absorbed doses. The compatibility of irradiated inner tubes with virgin butyl rubber was first investigated. Gamma irradiated inner tube wastes were replaced with butyl rubber up to 15 phr in the compound recipe. Similar recipes were also prepared by using the same quantity of commercial butyl rubber crumbs devulcanized by conventional methods. The rheological and mechanical properties and carbon black dispersion degree for both types of compounds prepared by using inner tubes scraps and commercial butyl crumbs were measured and were compared to the values of virgin butyl rubber compound. It is well known that mechanical properties are deteriorated when rubber crumb is added to the virgin compound. It was observed that the decrease in the mechanical properties was much lower for the compounds prepared from the tubes irradiated at 120 kGy than irradiated at 100 kGy. The better mechanical properties were obtained for the compounds prepared by recycling of irradiated inner tubes at 120 kGy than the compounds prepared by using commercial butyl crumbs. Almost similar carbon black distributions were observed for the all compounds studied. It has been concluded that gamma irradiated inner tubes are compatible

  9. Amended final report on the safety assessment of PPG-40 butyl ether with an addendum to include PPG-2, -4, -5, -9, -12, -14, -15, -16, -17, -18, -20, -22, -24, -26, -30, -33, -52, and -53 butyl ethers.

    Lanigan, R S

    2001-01-01

    The Polypropylene Glycol (PPG) Butyl Ethers function as skinand hair-conditioning agents in cosmetics. Intestinal absorption of the PPG Butyl Ethers was inversely proportional to the molecular weight. In general, the toxicity of the PPG Butyl Ethers decreased as the molecular weight increased. In acute studies, moderate intraperitoneal (IP) doses of various PPG Butyl Ethers caused convulsive seizures in mice and anesthetized dogs, and large oral doses caused decreased activity, anuria, renal tubular swelling and necrosis, and hepatic swelling and necrosis. PPG-2 Butyl Ether vapors were nontoxic by the inhalation route. PPG-2 Butyl Ether was nontoxic in short-term feeding and dermal exposure studies in rats. In animal irritation studies, PPG-2 Butyl Ether caused minor, transient erythema and desquamation; in addition, erythema, edema, ecchymosis, necrosis, and other changes were observed during an acute percutaneous study. PPG-2 Butyl Ether also caused minor to moderate conjunctival irritation and minor corneal injury. PPG-2 Butyl Ether when dermally applied was nontoxic to pregnant rats and was nonteratogenic at doses up to 1.0 ml/kg/day. PPG BE800 at concentrations of 0.001% to 0.26% in feed was noncarcinogenic to rats after 2 years of treatment. In clinical studies, PPG BE800 was nonirritating and nonsensitizing to the skin when tested using 200 subjects. PPG-40 Butyl Ether was neither an irritant nor a sensitizer in a repeat-insult patch test using 112 subjects. Although clinical testing did not indicate significant skin irritation is produced by these ingredients, the animal test data did indicate the potential that these ingredients can be irritating. Therefore, it was concluded that the PPG Butyl Ethers can be used safely in cosmetic products if they are formulated to avoid irritation. Data on the component ingredients, Propylene Glycol, PPG, and n-Butyl Alcohol, from previous cosmetic ingredient safety assessments were also considered and found to support

  10. Linear free energy relationships in heterogeneous catalysis--13. The dehydration of aliphatic alcohols over silica-alumina. [N-butyl alcohol, sec. -butyl or isopropyl alcohol, tert. -butyl alcolol

    Take, J; Matsumoto, T; Yoneda, Y

    1978-01-01

    The dehydration of n-butyl alcohol at 120/sup 0/-166/sup 0/C, sec.-butyl or isopropyl alcohol at 100/sup 0/-145/sup 0/C, and tert.-butyl alcohol at 54/sup 0/-80/sup 0/C, over silica/alumina catalyst was zero order in alcohol at 0.01-0.1 atm, and the activation energies were 35.3, 31.7, 32.0, and 29.9 kcal/mol, respectively. The zero-order rate constants were mainly affected by the activation energies since the preexponential factors varied little except for tert.-butyl alcohol. A linear relationship was found between the activation energy or the logarithm of the zero-order rate constant and the heterolytic bond dissociation energy for the carbon-oxygen bond in alcohols D(R/sup +/OH/sup -/). The activation energy increased and the rate constant decreased with increasing D(R/sup +/OH/sup -/). The results indicate that dehydration is E1 over this catalyst, but a similar correlation was observed based on published data for dehydration over alumina, which follows an E2 mechanism, indicating that heterolytic cleavage of the C-O bond is rate-determining in both mechanisms.

  11. APPLICATION OF PHOTOCATALYTIC PROCESS FOR REMOVAL OF METHYL TERT-BUTYL ETHER FROM HIGHLYCONTAMINATED WATER

    A. Mesdaghinia

    2007-09-01

    Full Text Available The oxygenate methyl tert-butyl ether is added to gasoline to increase the octane level and to reduce carbon monoxide and hydrocarbon emissions by vehicles. The high mobility, water solubility, and resistance to natural attenuation associated with methyl tert-butyl ether may result in contamination of ground and surface waters. In this research the degradation of aqueous methyl tert-butyl ether at relatively high concentrations was investigated by UV-vis/TiO2/H2O2 photocatalytic process. The effect of important operational parameters such as pH, amount of H2O2, catalyst loading, and irradiation time were also studied. Concentrations of methyl tert-butyl ether and intermediates such as tert-butyl formate and tert-butyl alcohol were measured over a 180 min period using a gas chromatograph equipped with flame ionization detector and combined with headspace sampler. Results showed that the time required for complete degradation increased from 30 to 180min, when the initial concentration was increased from 10 to 500mg/L. The first order rate constant for degradation of methyl tert-butyl ether from the hydroxyl radical was estimated to be 0.177 to 0.022 1/min as the concentration increased from 10 to 500mg/L. Study on the overall mineralization monitored by total organic carbon (TOC analysis showed that in the initial concentration of 100mg/L methyl tert-butyl ether, complete mineralization was obtained after 110min under UV-vis/TiO2/H2O2 photocatalytic process.

  12. 1-Butyl-3-Methylimidazolium Chloride Pretreatment on Malaysia Lignocellulose Wastes

    Lee, L.P.; Nur Hasyareeda Hassan; Muhammad Rahimi Yusop

    2015-01-01

    Ionic liquids (ILs) are of great interest as potential solvents for the production of fuels from lignocellulose biomass which is a potential source of bio fuels. To study the effects of pretreatment, 1-butyl-3-methylimidazolium chloride ([B mim]Cl) was used to pretreat woody plants, kempas (Koompassia malaccensis) and jelutong (Dyera costulata), and non-woody plants, kenaf (Hibiscus cannabinus) and rice husk (Oryza sativa) at 120 degree Celsius for 24 h. Cellulose was regenerated by the addition of water. The cell wall composition and structure of the lignocellulose bio masses before and after the ILs pretreatment were observed and characterized using field emission scanning electron microscopy (FESEM), attenuated total reflectance fourier transform infrared (ATR FT-IR) spectroscopy, and X-ray diffraction (XRD). After the pretreatment, enzymatic hydrolysis was carried out to identify the total reducing sugars (TRS) yields using dinitrosalicylic acid (DNS) method. Regenerated lignocellulose bio masses resulted in high TRS yields compared to their counter-parts which are in agreement with the findings of FESEM, ATR FT-IR and XRD that exhibited regenerated cellulose were less crystalline and more amorphous upon IL pretreatment. Therefore, kempas and jelutong can be alternate sources for the bio fuels production. (author)

  13. Gamma irradiation induced effects of butyl rubber based damping material

    Chen, Hong-Bing; Wang, Pu-Cheng; Liu, Bo; Zhang, Feng-Shun; Ao, Yin-Yong

    2018-04-01

    The effects of gamma irradiation on the butyl rubber based damping material (BRP) at various doses in nitrogen were investigated in this study. The results show that irradiation leads to radiolysis of BRP, with extractives increasing from 14.9 ± 0.8% of control to 37.2 ± 1.2% of sample irradiated at 350 kGy, while the swelling ratio increasing from 294 ± 3% to 766 ± 4%. The further investigation of the extractives with FTIR shows that the newly generated extractives are organic compounds containing C-H and C˭C bonds, with molecular weight ranging from 26,500 to 46,300. SEM characterization shows smoother surface with holes disappearing with increasing absorbed doses, consistent with "softer" material because of radiolysis. Dynamic mechanical study of BRP show that tan δ first slightly then obviously increases with increasing absorbed dose, while storage modulus slightly decreases. The tensile testing shows that the tensile strength decreases while the elongation at break increases with increasing dose. The positron annihilation lifetime spectroscopy show no obvious relations between free volume parameters and the damping properties, indicating the complicated influencing factors of damping properties.

  14. Dietary Exposure to Benzyl Butyl Phthalate in China

    ZHANG Lei; JIANG Ding Guo; SUI Hai Xia; WU Ping Gu; LIU Ai Dong; YANG Da Jin; LIU Zhao Ping; SONG Yan; LI Ning

    2016-01-01

    ObjectiveBenzyl butyl phthalate (BBP) is a plasticizer used in food contact materials. Dietary exposure to BBP might lead to reproduction and developmental damages to human. The present paper was aimed to assess the health risk of BBP dietary exposure in Chinese population. MethodsThe BBP contents were detected in 7409 food samples from 25 foodcategories by gas chromatography-mass spectrometry operated in selected ion monitoring (SIM) mode. The dietary exposures of BBP in different age and sex groups were estimated by combining the content data with food consumption data derived from 2002 China National Nutrient and Health Survey, and evaluated according to the tolerable daily intake (TDI) of BBP established by European Food safety Agency. ResultsIt was found that BBP was undetectable in most samples and the highest level was 1.69 mg/kg detected in a vegetable oil sample. The average dietary exposure of BBP in people aged≥2 years was 1.03 μg/kgbw perday and the highest average exposure was found in 2-6 years old children (1.98 μg/kg bw perday). The BBP exposure in 7-12 months old children excessed 10% of tolerable daily intake (TDI) in worst scenario. ConclusionThe health risk of BBP dietary exposure in Chinese population is low and, considering BBP alone, there is no safety concern.

  15. Embolotherapy using N-butyl cyanoacrylate for abdominal wall bleeding

    Choi, Young Ho; Koh, Young Hwan; Han, Dae Hee; Kim, Ji Hoon; Cha, Joo Hee; Lee, Eun Hye; Song, Chi Sung [Seoul National University Boramae Hospital, Seoul (Korea, Republic of)

    2008-05-15

    We describe our experience with the use of N-butyl cyanoacrylate (NBCA) embolization of abdominal wall bleeding and we evaluate the clinical effectiveness of the procedure. Embolization was performed in nine patients with abdominal wall bleeding. The sites of embolization were the left first lumbar (n = 1), left second lumbar (n = 1), right inferior epigastric (n 2), left inferior epigastric (n = 3), right circumflex iliac (n = 1), and left circumflex iliac artery (n = 1). A coil was used with NBCA in one patient due to difficulty in selecting only a bleeding focus and anticipated reflux. NBCA was mixed with Lipiodol at the ratio of 1:1 to 1:4. Blood pressure and heart rate were measured before and after the embolization procedure, and the serial hemoglobin and hematocrit levels and transfusion requirements were reviewed to evaluate hemostasis and rebleeding. Hemostasis was obtained in six out of the nine patients and technical success was achieved in all patients. There were no procedure-related complications. Four out of the nine patients died due to rebleeding of a subarachnoid hemorrhage (n = 1), multiorgan failure (n = 1), and hepatic failure (n =2) that occurred two to nine days after the embolization procedure. One patient had rebleeding. The five surviving patients had no rebleeding, and the patients continue to visit the clinical on an outpatient basis. NBCA embolization is a clinically safe procedure and is effective for abdominal wall bleeding.

  16. Biodegradation of methyl tert-butyl ether by Kocuria sp.

    Kiković Dragan D.

    2012-01-01

    Full Text Available Methyl tert-butyl ether (MTBE has been used to replace the toxic compounds from gasoline and to reduce emission of air pollutants. Due to its intensive use, MTBE has become one of the most important environment pollutants. The aim of this paper is isolation and identification of the bacteria from wastewater sample of “HIP Petrohemija” Pančevo (Serbia, capable of MTBE biodegradation. The results of the investigation showed that only the bacterial isolate 27/1 was capable of growth on MTBE. The result of sequence analyzes of 16S rDNA showed that this bacterial isolate belongs to the Kocuria sp. After the incubation period of 86 days, the degradation rates of initial MTBE concentration of 25 and 125 μg/ml were 55 and 36%, respectively. These results indicated that bacteria Kocuria sp. is successfully adapted on MTBE and can be potentially used in bioremediation of soils and waters contaminated with MTBE.

  17. Embolotherapy using N-butyl cyanoacrylate for abdominal wall bleeding

    Choi, Young Ho; Koh, Young Hwan; Han, Dae Hee; Kim, Ji Hoon; Cha, Joo Hee; Lee, Eun Hye; Song, Chi Sung

    2008-01-01

    We describe our experience with the use of N-butyl cyanoacrylate (NBCA) embolization of abdominal wall bleeding and we evaluate the clinical effectiveness of the procedure. Embolization was performed in nine patients with abdominal wall bleeding. The sites of embolization were the left first lumbar (n = 1), left second lumbar (n = 1), right inferior epigastric (n 2), left inferior epigastric (n = 3), right circumflex iliac (n = 1), and left circumflex iliac artery (n = 1). A coil was used with NBCA in one patient due to difficulty in selecting only a bleeding focus and anticipated reflux. NBCA was mixed with Lipiodol at the ratio of 1:1 to 1:4. Blood pressure and heart rate were measured before and after the embolization procedure, and the serial hemoglobin and hematocrit levels and transfusion requirements were reviewed to evaluate hemostasis and rebleeding. Hemostasis was obtained in six out of the nine patients and technical success was achieved in all patients. There were no procedure-related complications. Four out of the nine patients died due to rebleeding of a subarachnoid hemorrhage (n = 1), multiorgan failure (n = 1), and hepatic failure (n =2) that occurred two to nine days after the embolization procedure. One patient had rebleeding. The five surviving patients had no rebleeding, and the patients continue to visit the clinical on an outpatient basis. NBCA embolization is a clinically safe procedure and is effective for abdominal wall bleeding

  18. Atom transfer radical polymerization of n-butyl acrylate catalyzed by atom transfer radical polymerization of n-butyl acrylate catalyzed by

    Zhang, H.; Linde, van der R.

    2002-01-01

    The homogeneous atom transfer radical polymerization (ATRP) of n-butyl acrylate with CuBr/N-(n-hexyl)-2-pyridylmethanimine as a catalyst and ethyl 2-bromoisobutyrate as an initiator was investigated. The kinetic plots of ln([M]0/[M]) versus the reaction time for the ATRP systems in different

  19. Benzene and cyclohexane separation using 1-butyl-3-methylimidazolium thiocyanate

    Gonfa, Girma; Ismail, Marhaina; Bustam, Mohamad Azmi

    2017-09-01

    Cyclohexane is mainly produced by catalytic hydrogenation of benzene. Removal of unreacted benzene from the product stream is very important in this process. However, due to their close boiling points and azeotrope formation, it is very difficult to separate cyclohexane and benzene by conventional distillation. Currently, special separation processes such as processes extractive distillation is commercially used for this separation. However, this extractive distillation suffers from process complexity and higher energy consumption due to their low extractive selectivity of molecular entrainers used. The aim of the present work is to investigate the applicability of ionic liquids as entrainer in extractive distillation of benzene and cyclohexane mixture. In this study, we investigated 1-butyl-3-methylimidazolium thiocyanate ([BMIM][SCN]) ionic liquid for separation of benzene and cyclohexane by measuring the Vapor Liquid Equilibrium data of the two components in the presence of the ionic liquid. As green and potential environmentally friendly solvents, ionic liquids have attracted increasing attention as alternative conventional entrainers in extractive distillation. Isothermal Vapor Liquid Equilibrium for the benzene + cyclohexane + [BMIM][SCN] ternary system was obtained at 353.15 K using a Head Space Gas Chromatography. The addition of [BMIM][SCN] breaks the benzene-cyclohexane azeotrope and increased the relative volatility cyclohexane to benzene in the mixture. The effect of [BMIM][SCN] on the relative volatility cyclohexane to benzene was studied at various benzene and cyclohexane compositions and solvent to feed ratios. The performance of [BMIM][SCN] was compared with typical conventional solvents, dimethylformamide (DMF) and dimethylsulfoxide (DMSO). The results show that the relative volatility of cyclohexane to benzene in the presence of [BMIM][SCN] is higher compared that of DMSO and DMF.

  20. Pulse radiolysis of butyl acrylate in aqueous solution

    Kujawa, P.; Ulanski, P.; Rosiak, J.M.; Mohid, N.; Zaman, K.; Manshol, W.

    1998-01-01

    The pulse radiolysis of n-butyl acrylate (nBA) in aqueous solution was studied. The rate constant of the reaction of nBA with hydroxyl radicals was calculated as 1.5x10 10 dm 3 mol -1 s -1 . The absorption spectrum of the OH · -nBA adduct appeared to have a broad maximum at 300 nm. This spectrum was attributed to the α-carbon centred radicals. It decayed with the first-order rate constant k=1.5x10 4 s -1 (pH 10.8). The rate constant of the nBA reaction with hydrated electrons was determined as k=1.6x10 10 dm 3 mol -1 s -1 . The spectrum of H · -nBA adduct was similar to that recorded for OH · adduct. It decayed with first-order kinetics at k=1.0x10 4 s -1 . Spectra of the electron adduct were characterised by the band with a maximum at 285 nm (pH 10.0) or at 280 nm (pH 4.0) with ε=10500 dm 3 mol -1 cm -1 . In acidic solution, radical anion formed upon addition of hydrated electrons to the nBA molecule, undergoes fast, reversible protonation. The decay of the reversibly protonated electron adduct was a second-order process at k=2.5x10 9 dm 3 mol -1 s -1 . This reaction took place at the carbonyl oxygen. Slow, irreversible protonation of the electron adduct at high pH takes place at the β-carbon atom at k=2.9x10 4 s -1

  1. Transcatheter Embolotherapy with N-Butyl Cyanoacrylate for Ectopic Varices

    Choi, Jin Woo; Kim, Hyo-Cheol, E-mail: angiointervention@gmail.com; Jae, Hwan Jun, E-mail: jaemdphd@gmail.com; Jung, Hyun-Seok; Hur, Saebeom; Lee, Myungsu; Chung, Jin Wook [Seoul National University Hospital, Department of Radiology, Seoul National University College of Medicine (Korea, Republic of)

    2015-04-15

    PurposeTo address technical feasibility and clinical outcome of transcatheter embolotherapy with N-butyl cyanoacrylate (NBCA) for bleeding ectopic varices.MethodsThe institutional review board approved this retrospective study and waived informed consent. From January 2004 to June 2013, a total of 12 consecutive patients received transcatheter embolotherapy using NBCA for bleeding ectopic varices in our institute. Clinical and radiologic features of the endovascular procedures were comprehensively reviewed.ResultsPreprocedural computed tomography images revealed ectopic varices in the jejunum (n = 7), stoma (n = 2), rectum (n = 2), and duodenum (n = 1). The 12 procedures consisted of solitary embolotherapy (n = 8) and embolotherapy with portal decompression (main portal vein stenting in 3, transjugular intrahepatic portosystemic shunt in 1). With regard to vascular access, percutaneous transhepatic access (n = 7), transsplenic access (n = 4), and transjugular intrahepatic portosystemic shunt tract (n = 1) were used. There was no failure in either the embolotherapy or the vascular accesses (technical success rate, 100 %). Two patients died within 1 month from the procedure from preexisting fatal medical conditions. Only one patient, with a large varix that had been partially embolized by using coils and NBCA, underwent rebleeding 5.5 months after the procedure. The patient was retreated with NBCA and did not undergo any bleeding afterward for a follow-up period of 2.5 months. The remaining nine patients did not experience rebleeding during the follow-up periods (range 1.5–33.2 months).ConclusionTranscatheter embolotherapy using NBCA can be a useful option for bleeding ectopic varices.

  2. Carcinogenicity of methyl-tertiary butyl ether in gasoline.

    Mehlman, Myron A

    2002-12-01

    Methyl tertiary butyl ether (MTBE) was added to gasoline on a nationwide scale in 1992 without prior testing of adverse, toxic, or carcinogenic effects. Since that time, numerous reports have appeared describing adverse health effects of individuals exposed to MTBE, both from inhalation of fumes in the workplace and while pumping gasoline. Leakage of MTBE, a highly water-soluble compound, from underground storage tanks has led to contamination of the water supply in many areas of the United States. Legislation has been passed by many states to prohibit the addition of MTBE to gasoline. The addition of MTBE to gasoline has not accomplished its stated goal of decreasing air pollution, and it has posed serious health risks to a large portion of the population, particularly the elderly and those with respiratory problems, asthma, and skin sensitivity. Reports of animal studies of carcinogenicity of MTBE began to appear in the 1990s, prior to the widespread introduction of MTBE into gasoline. These reports were largely ignored. In ensuing years, further studies have shown that MTBE causes various types of malignant tumors in mice and rats. The National Toxicology Program (NTP) Board of Scientific Counselors' Report on Carcinogens Subcommittee met in December 1998 to consider listing MTBE as "reasonably anticipated to be a human carcinogen." In spite of recommendations from Dr. Bailer, the primary reviewer, and other scientists on the committee, the motion to list MTBE in the report was defeated by a six to five vote, with one abstention. On the basis of animal studies, it is widely accepted that if a chemical is carcinogenic in appropriate laboratory animal test systems, it must be treated as though it were carcinogenic in humans. In the face of compelling evidence, NTP Committee members who voted not to list MTBE as "reasonably anticipated to be a human carcinogen" did a disservice to the general public; this action may cause needless exposure of many to health risks

  3. Butyl acetate synthesis using immobilized lipase in calcium alginate beads

    Mohd Zulkhairi Abdul Rahim; Lee, Pat M.; Lee, Kong H.

    2008-01-01

    The esterification reaction of acetic acid and n-butanol using immobilized lipase encapsulated in calcium alginate beads (Lipase - CAB) and in chitosan coated calcium alginate beads (Lipase-CCAB) in n-hexane under mild reaction conditions were studied. Effects of temperature and substrate concentration (acetic acid and n-butanol) using Lipase - CAB, Lipase - CCAB and free lipase on the esterification reaction and their thermal stability towards esterification reaction were investigated. Results of temperature studies showed that the butyl acetate conversion increased with increase of temperature and reached the highest yield of about 70% around 50 degree Celsius for both immobilized systems but the yield of product catalyzed by free enzyme decreased as temperature was increased. Thermal stabilities studies showed that the Lipase-CCAB and Lipase-CAB were stable throughout the temperature range of 30-60 degree Celsius. However, free lipase became less stable at temperatures higher than 50 degree Celsius. The substrates, n-butanol and acetic acid exerted different effects on the esterification reaction and the reaction was favoured by higher acetic acid concentration than butanol. Kinetics parameters, Km and Vmax values for both substrates and the specific activities of the three enzyme system were also determined. The beads morphology was examined using SEM. Batch-wise operational stability studies for both immobilized systems demonstrated that the immobilized lipase performed better in the batch wise reactor system than the continuous bioreactor system and that the immobilized lipase remained active for at least 5 cycles of batch wise esterification reactions. (author)

  4. Effects of simulant mixed waste on EPDM and butyl rubber

    Nigrey, P.J.; Dickens, T.G.

    1997-11-01

    The authors have developed a Chemical Compatibility Testing Program for the evaluation of plastic packaging components which may be used in transporting mixed waste forms. In this program, they have screened 10 plastic materials in four liquid mixed waste simulants. These plastics were butadiene-acrylonitrile copolymer (Nitrile) rubber, cross-linked polyethylene, epichlorohydrin rubber, ethylene-propylene (EPDM) rubber, fluorocarbons (Viton and Kel-F trademark), polytetrafluoro-ethylene (Teflon), high-density polyethylene, isobutylene-isoprene copolymer (Butyl) rubber, polypropylene, and styrene-butadiene (SBR) rubber. The selected simulant mixed wastes were (1) an aqueous alkaline mixture of sodium nitrate and sodium nitrite; (2) a chlorinated hydrocarbon mixture; (3) a simulant liquid scintillation fluid; and (4) a mixture of ketones. The screening testing protocol involved exposing the respective materials to approximately 3 kGy of gamma radiation followed by 14-day exposures to the waste simulants at 60 C. The rubber materials or elastomers were tested using Vapor Transport Rate measurements while the liner materials were tested using specific gravity as a metric. The authors have developed a chemical compatibility program for the evaluation of plastic packaging components which may be incorporated in packaging for transporting mixed waste forms. From the data analyses performed to date, they have identified the thermoplastic, polychlorotrifluoroethylene, as having the greatest chemical compatibility after having been exposed to gamma radiation followed by exposure to the Hanford Tank simulant mixed waste. The most striking observation from this study was the poor performance of polytetrafluoroethylene under these conditions. In the evaluation of the two elastomeric materials they have concluded that while both materials exhibit remarkable resistance to these environmental conditions, EPDM has a greater resistance to this corrosive simulant mixed waste

  5. N-butyl cyanoacrylate embolotherapy for acute gastroduodenal ulcer bleeding

    Choi, Young Ho; Kim, Ji Hoon; Koh, Young Hwan; Han, Dae Hee; Cha, Joo Hee; Seong, Chang Kyu; Song, Chi Sung [Seoul National University Boramae Hospital, Seoul (Korea, Republic of)

    2007-01-15

    Various embolic agents have been used for embolization of acute gastrointestinal (GI) arterial bleeding. N-butyl cyanoacrylate (NBCA) is not easy to handle, but it is a useful embolic agent. In this retrospective study, we describe our experience with NBCA embolization of acute gastroduodenal ulcer bleeding. NBCA embolization was performed in seven patients with acute upper GI arterial bleeding; they had five gastric ulcers and two duodenal ulcers. NBCA embolization was done in the left gastric artery (n = 3), right gastric artery (n = 2), gastroduodenal artery (n = 1) and pancreaticoduodenal artery (n = 1). Coil was used along with NBCA in a gastric bleeding patient because of difficulty in selecting a feeding artery. NBCA was mixed with Lipiodol at the ratio of 1:1 to 1:2. The blood pressure and heart rate around the time of embolization, the serial hemoglobin and hematocrit levels and the transfusion requirements were reviewed to evaluate hemostasis and rebleeding. Technical success was achieved in all the cases. Two procedure-related complications happened; embolism of the NBCA mixture to the common hepatic artery occurred in a case with embolization of the left gastric artery, and reflux of the NBCA mixture occurred into the adjacent gastric tissue, but these did not cause any clinical problems. Four of seven patients did not present with rebleeding, but two had rebleeding 10 and 16 days, respectively, after embolization and they died of cardiac arrest at 2 months and 37 days, respectively. One other patient died of sepsis and respiratory failure within 24 hours without rebleeding. NBCA embolization with or without other embolic agents could be safe and effective for treating acute gastroduodenal ulcer bleeding.

  6. N-butyl cyanoacrylate embolotherapy for acute gastroduodenal ulcer bleeding

    Choi, Young Ho; Kim, Ji Hoon; Koh, Young Hwan; Han, Dae Hee; Cha, Joo Hee; Seong, Chang Kyu; Song, Chi Sung

    2007-01-01

    Various embolic agents have been used for embolization of acute gastrointestinal (GI) arterial bleeding. N-butyl cyanoacrylate (NBCA) is not easy to handle, but it is a useful embolic agent. In this retrospective study, we describe our experience with NBCA embolization of acute gastroduodenal ulcer bleeding. NBCA embolization was performed in seven patients with acute upper GI arterial bleeding; they had five gastric ulcers and two duodenal ulcers. NBCA embolization was done in the left gastric artery (n = 3), right gastric artery (n = 2), gastroduodenal artery (n = 1) and pancreaticoduodenal artery (n = 1). Coil was used along with NBCA in a gastric bleeding patient because of difficulty in selecting a feeding artery. NBCA was mixed with Lipiodol at the ratio of 1:1 to 1:2. The blood pressure and heart rate around the time of embolization, the serial hemoglobin and hematocrit levels and the transfusion requirements were reviewed to evaluate hemostasis and rebleeding. Technical success was achieved in all the cases. Two procedure-related complications happened; embolism of the NBCA mixture to the common hepatic artery occurred in a case with embolization of the left gastric artery, and reflux of the NBCA mixture occurred into the adjacent gastric tissue, but these did not cause any clinical problems. Four of seven patients did not present with rebleeding, but two had rebleeding 10 and 16 days, respectively, after embolization and they died of cardiac arrest at 2 months and 37 days, respectively. One other patient died of sepsis and respiratory failure within 24 hours without rebleeding. NBCA embolization with or without other embolic agents could be safe and effective for treating acute gastroduodenal ulcer bleeding

  7. The Effect of Nylon and Polyester Peel Ply Surface Preparation on the Bond Quality of Composite Laminates

    Moench, Molly K.

    The preparation of the surfaces to be bonded is critical to the success of composite bonds. Peel ply surface preparation is attractive from a manufacturing and quality assurance standpoint, but is a well known example of the extremely system-specific nature of composite bonds. This study examined the role of the surface energy, morphology, and chemistry left by peel ply removal in resulting bond quality. It also evaluated the use of contact angle surface energy measurement techniques for predicting the resulting bond quality of a prepared surface. The surfaces created by preparing three aerospace fiber-reinforced composite prepregs were compared when prepared with a nylon vs a polyester peel ply. The prepared surfaces were characterized with contact angle measurements with multiple fluids, scanning electron microscopy (SEM), and x-ray electron spectroscopy. The laminates were bonded with aerospace grade film adhesives. Bond quality was assessed via double cantilever beam testing followed by optical and scanning electron microscopy of the fracture surfaces.The division was clear between strong bonds (GIC of 600- 1000J/m2 and failure in cohesion) and weak bonds (GIC of 80-400J/m2 and failure in adhesion). All prepared laminates showed the imprint of the peel ply texture and evidence of peel ply remnants after fabric removal, either through SEM or XPS. Within an adhesive system, large amounts of SEM-visible peel ply material transfer correlated with poor bond quality and cleaner surfaces with higher bond quality. The both sides of failed weak bonds showed evidence of peel ply remnants under XPS, showing that at least some failure is occurring through the remnants. The choice of adhesive was found to be significant. AF 555 adhesive was more tolerant of peel ply contamination than MB 1515-3. Although the bond quality results varied substantially between tested combinations, the total surface energies of all prepared surfaces were very similar. Single fluid contact angle

  8. Relative efficacy of the argon green, argon blue-green, and krypton red lasers for 10-0 nylon subconjunctival laser suture lysis.

    Mudgil, A V; To, K W; Balachandran, R M; Janigian, R H; Tsiaras, W G

    1999-01-01

    To determine the optimal wavelength for subconjunctival laser suture lysis. 130 black monofilament 10-0 nylon sutures were sewn subconjunctivally into the bare sclera of enucleated rabbit globes. The lowest energy levels facilitating laser suture lysis were determined for the argon green (514.5 NM), argon blue-green (488.0 NM, 514.5 NM), and krypton red (647.1 NM) wavelengths. In addition, absorption spectroscopy was performed on the suture material and conjunctiva using the Perkin Elmer W/VIS Lambda 2 spectrometer. Krypton red produced the fewest buttonhole defects, and it was also the most efficient energy source for suture lysis (P = 0.0001) under nontenectomized conjunctiva. Absorbance spectra studies revealed peak absorbance at 628 NM for the 10-0 nylon suture material. Based on animal and absorption spectroscopy studies, krypton red may be a safer and more efficient wavelength for subconjunctival laser suture lysis.

  9. Reverse-Bumpy-Ball-Type-Nanoreactor-Loaded Nylon Membranes as Peroxidase-Mimic Membrane Reactors for a Colorimetric Assay for H₂O₂.

    Tong, Ying; Jiao, Xiangyu; Yang, Hankun; Wen, Yongqiang; Su, Lei; Zhang, Xueji

    2016-04-01

    Herein we report for the first time fabrication of reverse bumpy ball (RBB)-type-nanoreactor-based flexible peroxidase-mimic membrane reactors (MRs). The RBB-type nanoreactors with gold nanoparticles embedded in the inner walls of carbon shells were loaded on nylon membranes through a facile filtration approach. The as-prepared flexible catalytic membrane was studied as a peroxidase-mimic MR. It was found that the obtained peroxidase-mimic MR could exhibit several advantages over natural enzymes, such as facile and good recyclability, long-term stability and easy storage. Moreover, the RBB NS-modified nylon MRs as a peroxidase mimic provide a useful colorimetric assay for H₂O₂.

  10. High energy radiation effects on mechanical properties of butyl rubber compounds

    Pozenato, Cristina A.; Scagliusi, Sandra R.; Cardoso, Elisabeth C.L.; Lugao, Ademar B.

    2013-01-01

    The high energy radiation on butyl rubber compounds causes a number of chemical reactions that occur after initial ionization and excitation events. These reactions lead to changes in molecular mass of the polymer through scission and crosslinking of the molecules, being able to affect the physical and mechanical properties. Butyl rubber has excellent mechanical properties and oxidation resistance as well as low gas and water vapor permeability. Due to all these properties butyl rubber is widely used industrially and particularly in tires manufacturing. In accordance with various authors, the major effect of high energy, such as gamma rays in butyl rubber, is the yielding of free-radicals along with changes in mechanical properties. There were evaluated effects imparted from high energy radiation on mechanical properties of butyl rubber compounds, non-irradiated and irradiated with 25 kGy, 50 kGy, 150 kGy and 200 kGy. It was also observed a sharp reducing in stress rupture and elongation at break for doses higher than 50 kGy, pointing toward changes in polymeric chain along build-up of free radicals and consequent degradation. (author)

  11. The use of nylon and glass fiber filter separators with different pore sizes in air-cathode single-chamber microbial fuel cells

    Zhang, Xiaoyuan

    2010-01-01

    Separators are needed in microbial fuel cells (MFCs) to reduce electrode spacing and preventing electrode short circuiting. The use of nylon and glass fiber filter separators in single-chamber, air-cathode MFCs was examined for their effect on performance. Larger pore nylon mesh were used that had regular mesh weaves with pores ranging from 10 to 160 μm, while smaller pore-size nylon filters (0.2-0.45 μm) and glass fiber filters (0.7-2.0 μm) had a more random structure. The pore size of both types of nylon filters had a direct and predictable effect on power production, with power increasing from 443 ± 27 to 650 ± 7 mW m-2 for pore sizes of 0.2 and 0.45 μm, and from 769 ± 65 to 941 ± 47 mW m-2 for 10 to 160 μm. In contrast, changes in pore sizes of the glass fiber filters resulted in a relatively narrow change in power (732 ± 48 to 779 ± 43 mW m-2) for pore sizes of 0.7 to 2 μm. An ideal separator should increase both power density and Coulombic efficiency (CE). However, CEs measured for the different separators were inversely correlated with power production, demonstrating that materials which reduced the oxygen diffusion into the reactor also hindered proton transport to the cathode, reducing power production through increased internal resistance. Our results highlight the need to develop separators that control oxygen transfer and facilitate proton transfer to the cathode. © 2010 The Royal Society of Chemistry.

  12. Novel use of positively charged nylon transfer membranes for trapping indoleacetic acid or other small anions during efflux from plant tissues

    Evans, M. L.; Hangarter, R. P.

    1993-01-01

    Positively charged nylon blotting membranes were used as an anion binding medium to trap [14C]indoleactic acid (IAA) as it exited cells at the basal ends of Coleus blumei L. stem and Zea mays L. coleoptile segments. Autoradiography was used to visualize where the [14C] that moved out of the cut ends was localized on the nylon membrane. Diffusion of [14C]IAA from the initial point of contact with the nylon membrane was minimal. Comparison of the autoradiograms with anatomical tissue prints of the cut ends of the segments was used to determine what tissues participate in IAA movement. The results of these initial studies were consistent with other reports suggesting that [14C]IAA movement was primarily associated with vascular tissues in both C. blumei stems and corn coleoptiles, but the resolution was not sufficient to identify which vascular tissues were involved in IAA transport. With further refinements, this technique could also be used for studying the movement of other small charged molecules through plant tissues.

  13. Eco-Friendly Acaricidal Effects of Nylon 66 Nanofibers via Grafted Clove Bud Oil-Loaded Capsules on House Dust Mites.

    Kim, Joo Ran; Kim, Seong Hun

    2017-07-10

    Acaricidal nylon 66 fabrics (AN66Fs) grafted with clove oil-loaded microcapsules (COMCs) were developed against Dermatophagoides farina ( D. gallinae ). The average diameter was about 2.9 µm with a range of 100 nm-8.5 µm. COMCs carried clove oil loading of about 65 vol %. COMCs were chemically grafted to electrospun nylon nanofibers by the chemical reactions between -OH groups of COMCs and -COOH end groups of nylon fabrics to form ester linkages. AN66Fs had an effect on D. farinae depending on COMCs loadings. The increase in COMCs loading of AN66Fs from 5 to 15 wt % increased from 22% to 93% mortality against D. farinae within 72 h. However, AN66Fs containing over 20 wt % COMCs were more effective, showing up to 100% mortality within 24 h because the large amount of monoterpene alcohol, eugenol. This research suggests the use of clove oil and its major constituent eugenol as eco-friendly bioactive agents that can serve as a replacement for synthetic acaricides in controlling the population of D. farinae .

  14. Radiation effects on the immiscible polymer blend of nylon1010 and high-impact polystyrene (HIPS) I: Gel/dose curves, mathematical expectation theorem and thermal behaviour

    Dong, W.; Zhang, W.; Chen, G.; Liu, J.

    2000-01-01

    This paper studies the radiation properties of the immiscible blend of nylon1010 and HIPS. The gel fraction increased with increasing radiation dose. The network was found mostly in nylon1010, the networks were also found in both nylon1010 and HIPS when the dose reaches 0.85 MGy or more. We used the equation and the modified Zhang-Sun-Qian equation to simulate the relationship with the dose and the sol fraction. The latter equation fits well with these polymer blends and the relationship used by it showed better linearity than the one by the equation. We also studied the conditions of formation of the network by the mathematical expectation theorem for the binary system. Thermal properties of polymer blend were observed by DSC curves. The crystallization temperature decreases with increasing dose because the cross-linking reaction inhibited the crystallization procession and destroyed the crystals. The melting temperature also reduced with increasing radiation dose. The dual melting peak gradually shifted to single peak and the high melting peak disappeared at high radiation dose. However, the radiation-induced crystallization was observed by the heat of fusion increasing at low radiation dose. On the other hand, the crystal will be damaged by radiation. A similar conclusion may be drawn by the DSC traces when the polymer blends were crystallized. When the radiation dose increases, the heat of fusion reduces dramatically and so does the heat of crystallization. (author)

  15. Dose-rate and humidity effects upon the gamma-radiation response of nylon-based radiachromic film dosimeters

    Gehringer, P.; Eschweiler, H.; Proksch, E.

    1979-10-01

    At dose-rates typical for 60 Co gamma irradiation sources, the radiation response of hexahydroxyethyl pararosaniline cyanide/ 50μm nylon radiachromic films is dependent upon dose-rate as well as upon the moisture content of the films, or the relative humidity of the surrounding atmosphere, respectively. Under equilibrium moisture conditions, the response measured at 606 nm 24 hours after end of irradiation shows its highest dose-rate dependence at about 32 % r.h. A decrease in dose-rate from 2.8 to 0.039 Gy.s -1 results in a decrease in response by 17%. At higher humidities, the sensitivity of the film as well as the rate dependence decreases and at 86% r.h. no discernible dose-rate effect could be found. At lower humidities than 32% a flat maximum in response follows. At nominal 0% r.h. a second absorption band at 412 nm appears which is converted completely to an additional 606 nm absorption by exposure to a humid atmosphere. After that procedure the resultant response is somewhat lower than but shows almost the same dose-rate dependence as at 32% r.h. or else to eliminate the dose-rate effect by an extrapolation procedure based on the fact that the rate dependence vanishes at zero dose. (author)

  16. Processing of Micro and Nanofibers of Polypyrrole/Polyethylene Oxide/Nylon-6 by the Technique of Electrospinning

    Olvera-Gracia Manuel

    2013-10-01

    Full Text Available Micro and nano-fibers from polymers in solution can be easily obtained by using the so called electrospinning technique. The principle of this technique relies on apply- ing a positive voltage to the polymer solution and a negative voltage to a collector. By increasing voltage, the surface tension will be overcome and will eject some kind of fiber deposited on the collector. The continuous fibers production will be formed like a membrane. The fibers provide a large surface area due to their small diameter, therefore, their application is considered of commercial and scientific interest. In this study, fibers from a solution made of nylon-6, polyethylene oxide and polypyrrole were obtained. Chloroform and formic acid were used as solvents for these polymers. The fibers obtained were characterized by scanning electron microscopy, FT-IR spectroscopy, X-ray diffraction and electrical conductivity. These results indicate that the diameters of the composite fibers are on the micro and nanometric range, and the conductivity thereof is that of a semiconductor material.

  17. Two interdependent mechanisms of antimicrobial activity allow for efficient killing in nylon-3-based polymeric mimics of innate immunity peptides.

    Lee, Michelle W; Chakraborty, Saswata; Schmidt, Nathan W; Murgai, Rajan; Gellman, Samuel H; Wong, Gerard C L

    2014-09-01

    Novel synthetic mimics of antimicrobial peptides have been developed to exhibit structural properties and antimicrobial activity similar to those of natural antimicrobial peptides (AMPs) of the innate immune system. These molecules have a number of potential advantages over conventional antibiotics, including reduced bacterial resistance, cost-effective preparation, and customizable designs. In this study, we investigate a family of nylon-3 polymer-based antimicrobials. By combining vesicle dye leakage, bacterial permeation, and bactericidal assays with small-angle X-ray scattering (SAXS), we find that these polymers are capable of two interdependent mechanisms of action: permeation of bacterial membranes and binding to intracellular targets such as DNA, with the latter necessarily dependent on the former. We systemically examine polymer-induced membrane deformation modes across a range of lipid compositions that mimic both bacteria and mammalian cell membranes. The results show that the polymers' ability to generate negative Gaussian curvature (NGC), a topological requirement for membrane permeation and cellular entry, in model Escherichia coli membranes correlates with their ability to permeate membranes without complete membrane disruption and kill E. coli cells. Our findings suggest that these polymers operate with a concentration-dependent mechanism of action: at low concentrations permeation and DNA binding occur without membrane disruption, while at high concentrations complete disruption of the membrane occurs. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. USE OF THE MOBILE NYLON BAG TECHNIQUE FOR MEASURING IN SITU DIGESTIBILITY OF SOME SUPPLIES FOOD AND AVOCADO IN PIGS

    Julio Ly Carmenatti

    2015-08-01

    Full Text Available The mobile nylon bag technique was used for measuring in situ digestibility of conventional feeds and avocado (Persea americana Mills products in three 70 kg pigs fitted with a simple cannula in duodenum. One 3x3 Latin square was used for determining in situ digestibility of soybean, maize and sorghum meal and another 3x3 Latin square for measuring in situ digestibility of seed, peel plus seed meal and the entire Nayaritean avocado fruit of Hass type, as well as of the commercial diet given ad libitum to animals. In a preliminary test conducted with only bags containing a commercial feedstuff, it was found that in situ digestibility of DM was on average 73.01%. In conventional feeds, soybean meal samples showed higher (P0.05 for N digestibility among avocado products, which was generally low (between 28.02 and 34.58%. In situ organic matter digestibility was linked to that of MS (r = 0.915; P<0.001, both in percent, in 42 examined samples, by the following found equation: y = 2.076 + 0.926 x. The herein described studies concerning the utilization of the mobile bag showed that it is possible to obtain a fast response in connection to the nutritive value of non conventional, tropical alimentary resources for pigs. On the other hand, the continuation of studies relative to the nutritive value of avocado products for pigs is highly recommended.

  19. Human milk containing specific secretory IgA inhibits binding of Giardia lamblia to nylon and glass surfaces.

    Samra, H K; Ganguly, N K; Mahajan, R C

    1991-06-01

    The effects of human milk, containing specific secretory IgA, on the adherence of Giardia lamblia trophozoites in the presence and in the absence of intestinal mucus in vitro were studied. It was found that the trophozoites treated with breast milk, containing specific secretory IgA to G. lamblia, showed a significant decrease (p less than 0.01) in adherence to nylon fibre columns and glass surfaces than did trophozoites treated with milk containing no SIgA antibodies. The adherence to glass surfaces was significantly more (p less than 0.01) in the presence of intestinal mucus than when the mucus was absent. Milk that did not contain specific secretory SIgA to G. lamblia did not decrease the adherence to glass surfaces either in the presence or in the absence of mucus. The fluorescence study revealed the binding of specific secretory IgA on the trophozoite surface. The results suggest that binding of SIgA antibodies in milk to G. lamblia trophozoites inhibits parasite adherence, thus protecting against this infection in breast-fed babies.

  20. Mechanical and Morphological Properties of Waste Short Nylon Fibers and Nanoclay Reinforced NR/SBR Rubber Nanocomposites

    Mohammad Andideh

    2013-02-01

    Full Text Available Natural rubber and styrene butadiene rubber (NR/SBR reinforced with short nylon fibers along with nanoclay (Cloisite 15A hybrid composites were prepared in an internal and a two roll-mill mixer by a three-step mixingprocess. The effects of fiber content at a constant loading of 3 wt% nanoclay were studied on the microstructure, mechanical and morphological properties of the prepared nanocomposites. The adhesion between the fiber and the rubber was enhanced by the addition of a dry bonding system consisting of resorcinol, hexamethylene tetramine and hydrated silica (HRH. The curing characteristics of the composites were determined and subsequently vulcanized at 150°C using a hot press. It was observed that the cure time and swelling index of the composites decreased while maximum torque, and cure rate increased with increasing of short fiber and nanoclay contents. Thestructure and fracture surface morphology of the nanocomposites were characterized using X-ray diffraction, scanning electron microscopy. X-ray diffraction results of nanocomposites indicated that the interlayer distance of silicate layers increased. The mechanical properties (tensile, tear strength, elongation-at-break and hardness ofnanocomposites containing virgin and waste fibers in the longitudinal direction are compared.

  1. Quantification and Evaluation of Soil Erosion in the Estuaries of Cameroon, Gulf of Guinea: Case of Nylon Area

    Eric Flavien Mbiakouo-Djomo

    2018-01-01

    Full Text Available The area of Nylon represents a sensible and vulnerable environment where water erosion is the cause of many soil losses contributing to the production and movement of sediments from the upstream to the lowest depths. The high level of rainfall in this town, soil texture (sand-clay-silt, and the anarchic occupation of the area play a part in the important deterioration of the bare ground on the upstream of the catchment area. This causes with time an instability of structures and living places which can lead to their progressive disappearance. In order to assess the quantities of displaced sediments, the studies on the quantification of soil moved annually by water erosion are carried out. A direct method is used consisting in using a minisimulator of rain (NEME in order to understand the phenomena involved and assess the quantity of sediments which can be moved. It helps in assessing erosion caused by the rain and extrapolating results over the catchment area of the chosen field of study. USLE relation has permit to make an extrapolation of the quantity of soil affected, and the result shows that the average potential of loss of soil is 153.57 t/ha/annum.

  2. In Vitro Deposition of Ca-P Nanoparticles on Air Jet Spinning Nylon 6 Nanofibers Scaffold For Bone Tissue Engineering

    Abdal-hay, Abdalla, E-mail: abda_55@jbnu.ac.kr [Dept. of Computer Science, Faculty of Engineering, Universidad de Cuenca, Cuenca 01.01.168 (Ecuador); Dept. of Bionano System Engineering, College of Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Dept. of Engineering Materials and Mechanical Design, Faculty of Engineering, South Valley University, Qena 83523 (Egypt); Oh, Yi Seul [Dept. of Mechanical Design Engineering, Advanced Wind Power System Research Institute, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Yousef, Ayman; Pant, Hem Raj [Dept. of Bionano System Engineering, College of Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Vanegas, Pablo [Dept. of Computer Science, Faculty of Engineering, Universidad de Cuenca, Cuenca 01.01.168 (Ecuador); Lim, Jae Kyoo, E-mail: jklim@jbnu.ac.kr [Dept. of Mechanical Design Engineering, Advanced Wind Power System Research Institute, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

    2014-07-01

    Microporous, non-woven nylon 6 (N6) scaffolds were prepared with an air jet spinning (AJS) approach. In this process, polymer fibers with diameters down to the nanometer range (nanofibers) were formed by subjecting a fluid jet to high pressure air. The effects of the solution conditions on the morphological appearance and average diameter of the as-spun N6 fibers and crystal structure were investigated. The morphological properties of the AJS membrane mats could easily be tailored by adjusting the concentration of the polymer solution. Solutions at high concentrations were necessary to form well-defined fibers without beads. The production rate (viz. solvent evaporation rate) had the greatest effect on the chain structure conformation of N6. The predominant structure phase of the N6 fibers fabricated by AJS was a thermodynamically stable α-form while the electrospinning fibers induced the metastable γ-form. AJS significantly enhanced the mechanical properties of the N6 mat. The bone formation ability of AJS fibers was evaluated by incubating the fibers in biomimetic simulated body fluid for 5 and 10 days at 37 °C. Overall, the new AJS approach developed for membrane structures has great potential for the fabrication of hard and soft tissue engineering scaffolds.

  3. Temporary diplopia upon hyoscine-N-butyl bromide administration: case report

    Migliorini R

    2013-05-01

    Full Text Available R Migliorini, R Malagola, M Mafrici, R Spena, L ArricoDepartment of Sense Organs, University of Rome "La Sapienza", Rome, ItalyAbstract: Hyoscine-N-butyl bromide is a widely used antispasmodic belonging to the belladonna alkaloid class of semisynthetic quaternary ammonium compounds. These compounds exert a spasmolytic action on the smooth muscles of the bile-gastrointestinal tract, genitourinary tract, salivary glands (xerostomia, and also on the visual apparatus – in particular, the irido-ciliary complex. As a consequence, they provoke collateral effects such as mydriasis and accommodation disturbances. We report the case of a 23-year-old woman who complained of not only "dry mouth" but also "cloudy vision" and a "diplopia", both of temporary type, 2 hours after oral administration of hyoscine-N-butyl bromide.Keywords: hyoscine-N-butyl bromide, accommodation disorders, temporary diplopia, fusion alteration, vertical strabismus

  4. Endoscopic application of n-butyl-2-cyanoacrylate on esophagojejunal anastomotic leak: a case report

    Angelopoulos Stamatis

    2011-03-01

    Full Text Available Abstract Introduction This case report describes an esophagojejunal anastomotic leak following total gastrectomy for gastric cancer. The leak was treated successfully with endoscopic application of n-butyl-2-cyanoacrylate. This is the first case report on the endoscopic application of cyanoacrylate alone for the treatment of an anastomotic leak. Case presentation This report describes a case of a 68-year-old Caucasian man who underwent surgery for gastric cancer. He underwent total gastrectomy and esophagojejunal anastomosis with Roux-en-Y anastomosis plus transverse colectomy. An anastomotic leak was treated conservatively at first for a total of three weeks. However, the leak persisted; therefore, the decision was made to apply topical endoscopic n-butyl-2-cyanoacrylate. Conclusion The endoscopic application of n-butyl-2-cyanoacrylate alone can be used successfully to treat esophagojejunal anastomotic leakage.

  5. Reaction of biscyclopentadienyl molybdendihalides with tert.-butyl hydroperoxide and its using for cyclohexene epoxidation

    Aleksandrov, Yu.A.; Fomin, V.M.; Kolmakov, A.O.

    1983-01-01

    As a result of reactions of biscyclopentadienyl molybden-dihalides (Cp 2 MoX 2 , X=Cl, Br or I) with tert.-butyl hydroperoxide, tert.-butylperoxides of biscyclopentadienyl molybdendichloride and-dibromide are synthesized for the first time, which are characterized by physico-chemical properties. Cyclohexene in the reaction mixture of Cp 2 MoX 2 with tert -butyl hydroperoxide is oxidated to form cyclohexene oxide, the reaction proceeding at a high rate and with a quantitative yield. Tert.-butylperoxide of biscyclopentadienyl molybdendihalide is responsible for the cyclohexene epoxidation reaction. The schemes for the mechanism of Cp 2 MoX 2 reactions with tert.-butyl hydroperoxide in the absence and presence of olefine are suggested

  6. Molecular recognition study of ethosuximide by the supramolecular probe, p-t-butyl calix(8)arene

    Meenakshi, C., E-mail: geethu.laxi@gmail.com [Department of Chemistry, Shri Meenakshi Government College for Women (Autonomous), Madurai 625002 (India); Sangeetha, P.; Ramakrishnan, V. [Department of Laser Studies, School of Physics, Madurai Kamaraj University, Madurai 625021 (India)

    2013-06-15

    The supramolecule, p-t-Butyl calix(8)arene, forms inclusion complex with the antiseizure drug molecule, ethosuximide. This feature is explained on the basis of optical absorption spectroscopy. Here p-t-Butyl calix(8)arene is the host molecule and ethosuximide is the guest molecule. The stoichiometry of the host–guest complex and the binding constant has been determined using Benesi–Hildebrand plot. Based on the result obtained the structure of the inclusion complex has been proposed. -- Highlights: ► Third generation supramolecule, t-butyl calix (8) arene, is used as a host molecule. ► Anti seizure drug molecule is used as a guest molecule. ► Inclusion complex is formed between the host and guest molecule.

  7. EFFECTS OF STIMULATOR SUBSTANCES ON AEROBIC METHYL TERT-BUTYL ETHER BIODEGRADATION BY MICROBIAL CONSORTIUM

    M. Farrokhi ، S. Ahmadizad

    2009-04-01

    Full Text Available In this study dissolved humic substances and yeast extract were tested in different concentrations for enhancing methyl tert-butyl ether mineralization by isolated microorganisms from a variety of sources. All experiments were conducted at a constant temperature of 25ºC. Vials of 50 mL and 125 mL volume sealed with Teflon-lined Mini-Nert caps was used for microcosm experiments. In all experiments 1% sodium azide were used as control. Samples of bacterial cultures that metabolize methyl tert-butyl ether have been analysed by direct GC analysis using flame ionization detector. Cultures able to metabolize have been found in activated sludge and soils. These microorganisms weregram-positive bacterium. An aerobic microbial consortium was enriched in laboratory for four months. Methyl tert-butyl ether has been shown to biodegrade under aerobic and co-metabolic conditions. A microbial consortium isolated from activated sludges was identified as Cocobacillus. The concentration of the initial attached biomass was about 0.11 g/L of dry weight. The maximum mineralization rate and beneficial effects of stimulator substances on aerobic biodegradation of methyl tert-butyl ether occurred with the culture by combined concentrations of 500 mg/L of yeast extract and 20 mg/L of peat humic growth support of microbial consortium within 216 h and in presence of high oxygen levels and well mixing conditions. It was shown that adding, peat humic and yeast extract together, had better stimulatory effect on methyl tert-butyl ether biodegradation. Results clearly showed a stimulatory effect on methyl tert-butyl ether consumption higher than 20%. Consortium was capable of degrading concentrations of ≤1000 mg/L, whereas concentrations of >1000 mg/L, were not degraded.

  8. Method for determination of methyl tert-butyl ether and its degradation products in water

    Church, C.D.; Isabelle, L.M.; Pankow, J.F.; Rose, D.L.; Tratnyek, P.G.

    1997-01-01

    An analytical method is described that can detect the major alkyl ether compounds that are used as gasoline oxygenates (methyl tert-butyl ether, MTBE; ethyl tert-butyl ether, ETBE; and tert-amyl methyl ether, TAME) and their most characteristic degradation products (tert-butyl alcohol, TBA; tert-butyl formate, TBF; and tert-amyl alcohol, TAA) in water at sub-ppb concentrations. The new method involves gas chromatography (GC) with direct aqueous injection (DAI) onto a polar column via a splitless injector, coupled with detection by mass spectrometry (MS). DAI-GC/MS gives excellent agreement with conventional purge-and-trap methods for MTBE over a wide range of environmentally relevant concentrations. The new method can also give simultaneous identification of polar compounds that might occur as degradation products of gasoline oxygenates, such as TBA, TBF, TAA, methyl acetate, and acetone. When the method was applied to effluent from a column microcosm prepared with core material from an urban site in New Jersey, conversion of MTBE to TBA was observed after a lag period of 35 days. However, to date, analyses of water samples from six field sites using the DAI-GC/MS method have not produced evidence for the expected products of in situ degradation of MTBE.An analytical method is described that can detect the major alkyl ether compounds that are used as gasoline oxygenates (methyl tert-butyl ether, MTBE; ethyl tert-butyl ether, ETBE; and tert-amyl methyl ether, TAME) and their most characteristic degradation products (tert-butyl alcohol, TBA; tert-butyl formate, TBF; and tert-amyl alcohol, TAA) in water at sub-ppb concentrations. The new method involves gas chromatography (GC) with direct aqueous injection (DAI) onto a polar column via a splitless injector, coupled with detection by mass spectrometry (MS). DAI-GC/MS gives excellent agreement with conventional purge-and-trap methods for MTBE over a wide range of environmentally relevant concentrations. The new method

  9. Temperature influence on mixing properties of {ethyl tert-butyl ether (ETBE) + gasoline additives}

    Gonzalez-Olmos, R.; Iglesias, M.

    2007-01-01

    The densities and ultrasonic velocity of {ethyl tert-butyl ether (ETBE) + (benzene, toluene, ethylbenzene, isooctane, tert-butyl alcohol, and ethanol)} over the temperature range (288.15 to 323.15) K and atmospheric pressure, have been measured over the whole concentration range. The experimental excess volumes and deviation of isentropic compressibilities data have been analysed in terms of different theoretical models. The gathered data improve open literature related to gasoline additives, and help to understand the ETBE volumetric and acoustic trend into different chemical environment

  10. Pressure-induced phase transition of 1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6

    Takekiyo, Takahiro; Hatano, Naohiro; Imai, Yusuke; Abe, Hiroshi; Yoshimura, Yukihiro

    2011-03-01

    We have investigated the pressure-induced Raman spectral change of 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) using Raman spectroscopy. The relative Raman intensity at 590 cm-1 of the CH2 rocking band assigned to the gauche conformer of the NCCC dihedral angle of the butyl group in the [bmim]+ cation increases when the pressure-induced liquid-crystalline phase transition occurs, while that at 610 cm-1 assigned to the trans conformer decreases. Our results show that the high-pressure phase transition of [bmim][PF6] causes the increase of the gauche conformer of the [bmim]+ cation.

  11. Percutaneous N-Butyl cyanoacrylate embolization of a pancreatic pseudoaneurysm after failed attempts of transcatheter embolization

    Kim, Ri Hyeon; Yoo, Roh Eul; Kim, Hyo Cheol [Seoul National University Medical Research Center, and Clinical Research Institute, Seoul National University Hospital, Seoul (Korea, Republic of)

    2014-10-15

    One common complication after major pancreatic surgery is bleeding. Herein we describe a case of pancreatic pseudoaneurysm which developed after pylorous preserving pancreaticoduodenectomy for common bile duct cancer. Three attempts of transcatheter embolization failed since feeders to the pseudoaneurysm had unfavorable anatomy. Direct percutaneous N-butyl cyanoacrylate injection was performed under fluoroscopy-guidance and the pseudoaneurysm was successfully treated. Percutaneous fluoroscopy-guided direct N-butyl cyanoacrylate injection may be a useful alternative when selective transcatheter embolization fails or is technically challenging.

  12. Stereosequence distributions of poly(t-butyl methacrylate)s prepared with butyllithium

    Suzuki, Toshimitsu; Yamada, Osamu; Watanabe, Yoshihisa; Takegami, Yoshinobu

    1982-01-01

    13 C NMR spectra of poly(t-butyl methacrylate)s (PBMA) prepared with butyl-lithium (n-BuLi) were studied. Methylene carbon resonances appeared as five overlapped peaks, which were interpreted as a combination of hexad stereosequence distributions. The stereosequence distribution of PBMA prepared with n-BuLi at -78 0 C obeyed the first order Markov chain model even polymerized in tetrahydrofuran (THF). Syndiotactic PBMA was obtained with azobisisobutyronitrile (AIBN) as the initiator, and the stereosequence distribution of this polymer agreed well with Bernoullian statistics. (author)

  13. Metabolism of the fungicide Denmert (S-n-butyl S'-p-tert-butyl-benzyl N-3-pyridyldithiocarbonimidate, S-1358) and Denmert sulfoxides in liver enzyme systems

    Ohkawa, Hideo; Okihara, Yukiko; Miyamoto, Junshi

    1976-01-01

    On incubation with rat liver microsomes plus MADPH, Denmert (S-n-butyl S'-p-tert-butylbenzyl N-3-pyridyldithiocarbonimidate) underwent at least two different types of oxidation; hydroxylation and sulfoxidation. Hydroxylation of Denmert at the tert-butyl group was one of the major metabolic attacks in mammalian metabolism. Sulfoxidation of Denmert gave two isomers of Denmert sulfoxides which were intermediates in the metabolism and readily transformed into 2-(3'-pyridylimino)-4-carboxylthiazolidine (HM) in the presence of L-cysteine without enzymatic mediation. This type of conjugation with cysteine appears to be a new class of metabolic reactions in mammals. Denmert S-oxide showed increased fungicidal activity when assayed in liquid cultures, but not on plant leaves. (auth.)

  14. Continuous synthesis of tert.-butyl peroxypivalate using a single channel micro reactor equipped with orifices as emulsification units

    Illg, T.; Hessel, V.; Löb, P.; Schouten, J.C.

    2011-01-01

    The two-step synthesis of tert-butyl peroxypivalate is performed in a single-channel microreactor. The first step, the deprotonation of tert-butyl hydroperoxide, is done in a simple mixer tube setup. The residence time section for the second reaction step is equipped with orifices for interfacial

  15. Diisobutyl phthalate has comparable anti-androgenic effects to di-n-butyl phthalate in fetal rat testis

    Boberg, Julie; Petersen, Marta Axelstad; Vinggaard, Anne

    2006-01-01

    Phthalates are widely used as plasticizers in various consumer products and building materials. Some of the phthalates are known to interfere with male reproductive development in rats, and di-n-butyl phthalate (DBP), diethylhexyl phthalate (DEHP) and butyl benzyl phthalate (BBP) were recently...

  16. On the viscosity of two 1-butyl-1-methylpyrrolidinium ionic liquids: effect of the temperature and pressure

    Gaciño, Félix M.; Comuñas, María J.P.; Regueira Muñiz, Teresa

    2015-01-01

    to measure viscosities as a function of temperature and pressure fortwo ionic liquids (ILs): 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphateand 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate.Besides, we have measured the flow curves at pressures up to 75 MPa and shear rates up...

  17. In situ 1H NMR studies of high-temperature nitroxide-mediated polymerization of n-butyl acrylate

    Hlalele, L.; Klumperman, L.

    2011-01-01

    This paper presents results on the independence of the rate of polymerization of n-butyl acrylate (n-BA) toward initial concentration of the alkoxyamine initiator. The alkoxyamine, 2-methyl-2-[N-tert-butyl-N-(1-diethoxyphosphoryl-2,2-dimethylpropyl)aminooxy]propionic acid (MAMA-DEPN), was used to

  18. Atomic Force Microscopy Based Thermal Lithography of Poly(tert-butyl acrylate) Block Copolymer Films for Bioconjugation

    Duvigneau, Joost; Schönherr, Holger; Vancso, Gyula J.

    2008-01-01

    In this paper, we report on the local thermal activation of thin polymer films for area-selective surface chemical modification on micrometer and nanometer length scales. The thermally induced activation of tert-butyl ester moieties in polystyrene-block-poly(tert-butyl acrylate) (PS-b-PtBA) block

  19. Third phase formation in the extraction of Th(NO{sub 3}){sub 4} by Tri-sec-butyl phosphate. A comparison with Tri-n-butyl phosphate

    Chandrasekar, Aditi; Suresh, A.; Sivaraman, N. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India). Chemistry Group

    2017-06-01

    Earlier studies carried out in our laboratory indicated that Tri-sec-butyl phosphate (TsBP) is a potential extractant for U/Th separation. Also, the third phase formation tendency of TsBP is lower compared to its isomers, Tri-n-butyl-phosphate (TBP) and Tri-iso-butyl phosphate (TiBP). In this context, the extraction and third phase formation behaviour of 1.1 M solutions of TiBP and TsBP in n-dodecane in the extraction of Th(IV) from 1 M HNO{sub 3} at 303 K over a wide range of Th concentrations were investigated in the present study and the results are compared with the literature data on TBP system. Concentrations of Th(IV) and HNO{sub 3} loaded in the organic phase before third phase formation (biphasic region) as well as in third phase and diluent-rich phase after third phase formation (triphasic region) were measured as a function of equilibrium aqueous phase Th(IV) concentration. The density of loaded organic phase was also measured at various Th(IV) concentrations. The extraction profiles in the biphasic region indicated that extraction of Th(IV) by TBP is higher than that of TiBP which in turn is higher than that of TsBP. Extractant concentration in the diluent-rich phase and third phase was measured for the triphasic region.

  20. Third phase formation in the extraction of Th(NO_3)_4 by Tri-sec-butyl phosphate. A comparison with Tri-n-butyl phosphate

    Chandrasekar, Aditi; Suresh, A.; Sivaraman, N.

    2017-01-01

    Earlier studies carried out in our laboratory indicated that Tri-sec-butyl phosphate (TsBP) is a potential extractant for U/Th separation. Also, the third phase formation tendency of TsBP is lower compared to its isomers, Tri-n-butyl-phosphate (TBP) and Tri-iso-butyl phosphate (TiBP). In this context, the extraction and third phase formation behaviour of 1.1 M solutions of TiBP and TsBP in n-dodecane in the extraction of Th(IV) from 1 M HNO_3 at 303 K over a wide range of Th concentrations were investigated in the present study and the results are compared with the literature data on TBP system. Concentrations of Th(IV) and HNO_3 loaded in the organic phase before third phase formation (biphasic region) as well as in third phase and diluent-rich phase after third phase formation (triphasic region) were measured as a function of equilibrium aqueous phase Th(IV) concentration. The density of loaded organic phase was also measured at various Th(IV) concentrations. The extraction profiles in the biphasic region indicated that extraction of Th(IV) by TBP is higher than that of TiBP which in turn is higher than that of TsBP. Extractant concentration in the diluent-rich phase and third phase was measured for the triphasic region.

  1. Double-Balloon-Assisted n-Butyl-2-Cyanoacrylate Embolization of Intrahepatic Arterioportal Shunt Prior to Chemoembolization of Hepatocellular Carcinoma

    Takao, Hidemasa, E-mail: takaoh-tky@umin.ac.jp; Shibata, Eisuke; Ohtomo, Kuni [University of Tokyo, Department of Radiology, Graduate School of Medicine (Japan)

    2016-10-15

    A case of multiple hepatocellular carcinomas with a severe intrahepatic arterioportal shunt that was successfully embolized with n-butyl-2-cyanoacrylate with coaxial double-balloon occlusion prior to transcatheter arterial chemoembolization is presented. A proximal balloon positioned at the proper hepatic artery was used for flow control, and a coaxial microballoon, positioned in the closest of three arterial feeding branches to the arterioportal shunt, was used to control the delivery of n-butyl-2-cyanoacrylate. This coaxial double-balloon technique can prevent proximal embolization and distal migration of n-butyl-2-cyanoacrylate and enable precise control of the distribution of n-butyl-2-cyanoacrylate. It could also be applicable to n-butyl-2-cyanoacrylate embolization for other than intrahepatic arterioportal shunt.

  2. Higher levels of ethyl paraben and butyl paraben in rat amniotic fluid than in maternal plasma after subcutaneous administration

    Frederiksen, Hanne; Taxvig, Camilla; Hass, Ulla

    2008-01-01

    to obtain more knowledge about the distribution of ethyl paraben and butyl paraben in pregnant rats and pups after perinatal exposure, the presented study was designed. The data show response and distribution of ethyl paraben and butyl paraben in maternal rat plasma, pools of amniotic fluids, placenta......, whole-body fetuses, and in fetal liver after dosing of dams with 100, 200, and 400 mg/kg body weight (bw)/day from gestational day 7 to 21. After cesarean section of dams, the fluids and tissues were collected, deconjugated, and purified by solid-phase extraction, and ethyl paraben and butyl paraben...... were analyzed by liquid chromatography-tandem mass spectrometry. Markedly higher levels of ethyl paraben compared to butyl paraben were found in all fluids and tissues. Both ethyl paraben and butyl paraben in maternal plasma, livers, and whole-body tissues from fetus seemed to be saturated after dosing...

  3. Is 3D printing safe? Analysis of the thermal treatment of thermoplastics: ABS, PLA, PET, and nylon.

    Wojtyła, Szymon; Klama, Piotr; Baran, Tomasz

    2017-06-01

    The fast development of low-cost desktop three-dimensional (3D) printers has made those devices widely accessible for goods manufacturing at home. However, is it safe? Users may belittle the effects or influences of pollutants (organic compounds and ultrafine particles) generated by the devices in question. Within the scope of this study, the authors attempt to investigate thermal decomposition of the following commonly used, commercially available thermoplastic filaments: acrylonitrile-butadiene-styrene (ABS), polylactic acid (PLA), polyethylene terephthalate (PET), and nylon. Thermogravimetric analysis has shown the detailed thermal patterns of their behavior upon increasing temperature in neutral atmosphere, while GC analysis of organic vapors emitted during the process of heating thermoplastics have made it possible to obtain crucial pieces of information about the toxicity of 3D printing process. The conducted study has shown that ABS is significantly more toxic than PLA. The emission of volatile organic compounds (VOC) has been in the range of 0.50 µmol/h. Styrene has accounted for more than 30% of total VOC emitted from ABS, while for PLA, methyl methacrylate has been detected as the predominant compound (44% of total VOCs emission). Moreover, the authors have summarized available or applicable methods that can eliminate formed pollutants and protect the users of 3D printers. This article summarizes theoretical knowledge on thermal degradation of polymers used for 3D printers and shows results of authors' investigation, as well as presents forward-looking solutions that may increase the safety of utilization of 3D printers.

  4. Nutritive value of wheat straw treated with gaseous or liquid ammonia trough nylon bag and in vitro gas production techniques

    Samad Sadeghi

    2016-04-01

    Full Text Available Introduction Feed shortage is the most important characteristic of Iranian animal industry. Increased costs of livestock production have caused the Iranian producers to reduce feed costs mainly by inclusion low quality crop residues into ruminants diets. It is estimated that around 20 million tons wheat straw produced in Iran every year. Both the digestibility and crude protein content of wheat straw are typically low. Since 1900, a wide variety of chemical treatments have been tested for their potential to improve the feeding value of wheat straw. Upgrading of wheat straw by ammoniation has been known for a long time, but application of this method of wheat straw treatment has received the least attention in the area (Khorasan Province, Iran. Therefore, the object of the present study was to evaluate the effect of gaseous and liquid ammonia on nutritive value of wheat straw through in vitro techniques. Material and Methods One kg dry wheat straw was placed into the plastic cylinders with dimension of 1 m (diameter and 1.8 m (height and 0.8 mm (thickness. Gaseous and liquid commercial ammonia was injected or added to the wrapped straw at the rate of 2, 4 and 6 percent. The treatment time was 1 month at room temperature (20-25 ºC. At the end of treatment period the cylinders were opened and the ammoniated straw exposed to the air for 4 days. The treated straws were sampled for the subsequent analyses. Dry matter degradability of the samples was done by using nylon bags (10x20 cm with pore size of 40 micron. About 2 g ground samples (2 mm were placed into the nylon bags and incubated in rumen of 4 permanently fistulated steers for 3, 6, 12, 24, 36, 48, 72, 96 and 120 hrs. The experimental steers were fed by the ordinary diet containing 65% forage and 35% concentrate twice daily. The Menke and Steingass method was followed for the in vitro gas production method. Result and discussion Crude protein (CP content of the treated wheat straw samples

  5. Photostabilization of Rhodamine 6G in acetone by β-carotene and t-butyl hydroxyanisole

    Aoki, Keisuke; Matsuda, Masahiro; Yamamoto, Daisuke; Abe, Yasuhiro; Akutsu, Shinya; Fujita, Koichi; Doi, Kazutaka; Kobayashi, Masami

    2011-01-01

    The photostability of Rhodamine 6G is of crucial importance for the organic light-emitting display of mobilephones. Photobleaching of Rhodamine 6G in acetone was not protected by β-carotene, but was efficientlyphotostabilized by t-butyl hydroxyanisole. The results indicate that photobleaching of Rhodamine 6G inacetone was not caused by singlet oxygen but some radical species.

  6. MONITORED NATURAL ATTENUATION OF TERTIARY BUTYL ALCOHOL (TBA) IN GROUND WATER AT GASOLINE SPILL SITES

    The state agencies that implement the Underground Storage Tank program rely heavily on Monitored Natural Attenuation (MNA) to clean up contaminants such as benzene and methyl tertiary butyl ether (MTBE) at gasoline spill sites. This is possible because the contaminants are biolo...

  7. Temperature effect on tert-butyl alcohol (TBA) biodegradation kinetics in hyporheic zone soils.

    Greenwood, Mark H; Sims, Ronald C; McLean, Joan E; Doucette, William J

    2007-09-19

    Remediation of tert-butyl alcohol (TBA) in subsurface waters should be taken into consideration at reformulated gasoline contaminated sites since it is a biodegradation intermediate of methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and tert-butyl formate (TBF). The effect of temperature on TBA biodegradation has not been not been published in the literature. Biodegradation of [U 14C] TBA was determined using hyporheic zone soil microcosms. First order mineralization rate constants of TBA at 5 degrees C, 15 degrees C and 25 degrees C were 7.84 +/- 0.14 x 10-3, 9.07 +/- 0.09 x 10-3, and 15.3 +/- 0.3 x 10-3 days-1, respectively (or 2.86 +/- 0.05, 3.31 +/- 0.03, 5.60 +/- 0.14 years-1, respectively). Temperature had a statistically significant effect on the mineralization rates and was modelled using the Arrhenius equation with frequency factor (A) and activation energy (Ea) of 154 day-1 and 23,006 mol/J, respectively. Results of this study are the first to determine mineralization rates of TBA for different temperatures. The kinetic rates determined in this study can be used in groundwater fate and transport modelling of TBA at the Ronan, MT site and provide an estimate for TBA removal at other similar shallow aquifer sites and hyporheic zones as a function of seasonal change in temperature.

  8. IRIS Toxicological Review of Ethylene Glycol Mono Butyl Ether (Egbe) (Final Report)

    EPA has finalized the Toxicological Review of Ethylene Glycol Mono Butyl Ether: in support of the Integrated Risk Information System (IRIS). Now final, this assessment may be used by EPA’s program and regional offices to inform decisions to protect human health.

  9. IRIS Toxicological Review of Ethylene Glycol Mono-Butyl Ether (Egbe) (Interagency Science Discussion Draft)

    EPA released the draft report, Toxicological Review for Ethylene Glycol Mono-Butyl Ether , that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the IRIS Assessment Development Process. Comments received from ot...

  10. Morphology and film formation of poly(butyl methacrylate)-polypyrrole core-shell latex particles

    Huijs, F; Lang, J

    Core-shell latex particles made of a poly(butyl methacrylate) (PBMA) core and a thin polypyrrole (PPy) shell were synthesized by two-stage polymerization. In the first stage, PBMA latex particles were synthesized in a semicontinuous process by free-radical polymerization. PBMA latex particles were

  11. Emulsion (Co)polymerization of styrene and butyl acrylate monitored by On-line Raman Spectroscopy

    van den Brink, H.J.T.; Pepers, M.L.H.; Herk, van A.M.; German, A.L.

    2000-01-01

    The homo- and copolymerizations of styrene and n-butyl acrylate were studied by on-line in-situ Raman spectroscopy.Results from the solution (homo)polymerizations proved to be very useful in the quantification of the Raman data from the emulsion homopolymerization. From the homopolymerization data

  12. A Case of Successful Ablation of a Gastrophrenic Fistula with n-Butyl-2-Cyanoacrylate

    Ashish Mahajan

    2008-01-01

    Full Text Available A 79-year-old woman with a fistula between a subphrenic abscess and the fundus of the stomach was successfully treated with n-Butyl-2-Cyanoacrylate. Conservative management had failed. Clinical presentation, treatment progress and imaging findings by computed tomography scan, ultrasound, gastroscopy and fluoroscopy are presented, along with a brief review of the relevant literature.

  13. Carcinogenicity study on butylated hydroxytoluene (BHT) in Wistar rats exposed in utero

    Olsen, P.; Meyer, Otto A.; Bille, N.

    1986-01-01

    Groups of 60, 40, 40 and 60 F0 Wistar rats of each sex were fed a semi-synthetic diet containing butylated hydroxytoluene (BHT) in concentrations to provide intakes of 0, 25, 100 or 500 mg/kg body weight/day, respectively. The F0 rats were mated and groups of 100, 80, 80 or 100 F1 rats of each sex...

  14. Transdermal uptake of diethyl phthalate and di(n-butyl) phthalate directly from air: Experimental verification

    Weschler, Charles J.; Bekö, Gabriel; Koch, Holger M.

    2015-01-01

    of phthalate esters. Objectives: This study investigated transdermal uptake, directly from air, of diethyl phthalate (DEP) and di(n-butyl) phthalate (DnBP) in humans. Methods: In a series of experiments, six human participants were exposed for 6 hr in a chamber containing deliberately elevated air...

  15. Solubility of carbon dioxide in secondary butyl alcohol at high pressures : experimental and modeling with CPA

    Raeissi, S.; Haghbaksh, R.; Florusse, L.J.; Peters, C.J.

    2015-01-01

    Mixtures of carbon dioxide and secondary butyl alcohol at high pressures are interesting for a range of industrial applications. Therefore, it is important to have trustworthy experimental data on the high-pressure phase behavior of this mixture over a wide range of temperatures. In addition, an

  16. Characterization of Z-RAFT star polymerization of butyl acrylate by size-exclusion chromatography

    Boschmann, D.; Edam, R.; Schoenmakers, P.J.; Vana, P.

    2009-01-01

    Z-RAFT star polymerization of butyl acrylate using multifunctional trithiocarbonate-type RAFT agents carrying methyl propionate as the leaving group were used to form star polymers having 3, 4, and 6 arms. The polymerizations showed well controlled behavior up to high monomer conversions. By using a

  17. (R-N-{2-tert-Butyl-2-[(R-tert-butylsulfonamido]ethylidene}-tert-butanesulfonamide

    Cong-Bin Fan

    2008-10-01

    Full Text Available The title compound, C14H30N2O2S2, is the product of the monoaddition reaction of tert-butyl magnesium chloride with bis-[(R-N-tert-butanesulfinyl]ethanediimine. There are two almost identical molecules in the asymmetric unit, the molecular conformation of which is stabilized by an intramolecular N—H...N hydrogen bond.

  18. Oxidative DNA damage in male wistar rats exposed to di-n-butyl phthalate

    Wellejus, A.; Dalgaard, Majken; Loft, S.

    2002-01-01

    Dialkyl phthalate esters are used in the plastic industry and widely distributed in the environment, Previously, it has been shown that di-n-butyl phthalate (DBP) produces testicular atrophy and liver enlargement in rodents, and the mechanisms behind this could involve reactive oxygen species (ROS...

  19. Time-Resolved WAXD and SAXS Investigations on Butyl Branched Alkane at Elevated Pressures

    Rastogi, A.; Hobbs, J.K.; Rastogi, S.

    2002-01-01

    The crystallization behavior and the morphological aspect of the butyl branched alkane C96H193CH(C4H9)C94H189 have been investigated using time-resolved wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) at atmospheric and elevated pressures. The solution crystallized sample

  20. Simultaneous clostridial fermentation, lipase-catalyzed esterification, and ester extraction to enrich diesel with butyl butyrate

    Berg, C. van den; Heeres, A.S.; Wielen, L.A.M. van der; Straathof, A.J.J.

    2013-01-01

    The recovery of 1-butanol from fermentation broth is energy-intensive since typical concentrations in fermentation broth are below 20gL -1. To prevent butanol inhibition and high downstream processing costs, we aimed at producing butyl esters instead of 1-butanol. It is shown that it is possible to

  1. Continuous ARGET ATPR of methyl methacrylate and butyl acrylate in a stirred tank reactor

    Chan, N.; Meuldijk, J.; Cunningham, M.F.; Hutchinson, R.A.

    2013-01-01

    ARGET ATRP (activator regenerated by electron transfer atom transfer radical polymerization) of butyl acrylate (BA) and methyl methacrylate (MMA) was successfully adapted from a batch process to a continuous stirred tank reactor (CSTR) with 50 ppm copper. A series of batch polymerizations were first

  2. Critically evaluated rate coefficients for free-radical polymerization, 5. Propagation rate coefficient for butyl acrylate

    Asua, J.M.; Beuermann, S.; Buback, M.; Castignolles, P.; Charleux, B.; Gilbert, R.G.; Hutchinson, R.A.; Leiza, J.R.; Nikitin, A.N.; Vairon, J.P.; Herk, van A.M.

    2004-01-01

    Propagation rate coefficients, kp, for free-radical polymerization of butyl acrylate (BA) previously reported by several groups are critically evaluated. All data were determined by the combination of pulsed-laser polymerization (PLP) and subsequent polymer analysis by size exclusion (SEC)

  3. Risicogrenzen voor MTBE (Methyl tertiair-Butyl Ether) in bodem, sediment, grondwater, oppervlaktewater en voor drinkwaterbereiding

    Swartjes FA; Baars AJ; Fleuren RHLJ; Otte PF; LER

    2004-01-01

    Recentelijk is politieke commotie ontstaan ten gevolge van de mogelijke schadelijke gezondheidseffecten van Methyl tertiair-Butyl Ether (MTBE). Dit was reden voor het ministerie van VROM om het RIVM te verzoeken risicogrenzen voor MTBE in bodem, sediment, grondwater, oppervlaktewater, drinkwater en

  4. The effect of reducing monosaccharides on the atom transfer radical polymerization of butyl methacrylate

    Vries, de Andrew; Klumperman, B.; Wet-Roos, de D.; Sanderson, R.D.

    2001-01-01

    The effect of various reducing monosaccharides on the rate of atom transfer radical polymerization (ATRP) of butyl methacrylate is reported in this study. The addition of reducing sugars affects the rate of ATRP positively with a 100% increase in the rate of polymerization in some cases. In

  5. A new efficient synthesis of isothiocyanates from amines using di-tert-butyl dicarbonate

    Munch, Henrik; Hansen, Jon S.; Pittelkow, Michael

    2008-01-01

    Alkyl and aryl amines are converted smoothly to the corresponding isothiocyanates via the dithiocarbamates in good to excellent yields using di-tert-butyl dicarbonate (Boc(2)O) and 1-3 mol% of DMAP or DABCO as catalyst. As most of the byproducts are volatile, the work-up involves simple evaporation...

  6. Bilateral transrenal ureteral occlusion by means of n-butyl cyanoacrylate and AMPLATZER vascular plug

    Rosario F Grasso

    2014-01-01

    Full Text Available AMPLATZER vascular plug is a widely used embolic agent. In the present paper, we present a case of an 86-year-old female patient who underwent bilateral ureteral occlusion by means of AMPLATZER vascular plug II coupled to n-butyl cyanoacrylate (NBCA because of recurring pyelonephritis following cystectomy with subsequent bilateral ureterosigmoidostomy (sec. Mainz type II.

  7. Tri(t-butyl)phosphine-assisted selective hydrosilylation of terminal alkynes

    2010-01-01

    A highly efficient and regio-/stereoselective method of hydrosilylating terminal alkynes was developed using Pt(DVDS)-tri(t-butyl) phosphine catalyst system at room temperature.Trans-products or alpha-products were obtained almost exclusively depending on the alkynes and silanes employed.

  8. DERMAL, ORAL, AND INHALATION PHARMACOKINETICS OF METHYL TERTIARY BUTYL ETHER (MTBE) IN HUMAN VOLUNTEERS

    Methyl tertiary butyl ether (MTBE), a gasoline additive, used to increase octane and reduce carbon monoxide emissions and ozone precursors has contaminated drinking water leading to exposure by oral, inhalation, and dermal routes. To determine its dermal, oral, and inhalation ki...

  9. DERMAL, ORAL AND INHALATION PHARMACOKINETICS OF METHYL TERTIARY-BUTYL ETHER (MTBE) IN HUMAN VOLUNTEERS

    Methyl tertiary butyl ether (MTBE), a gasoline additive used to increase octane and reduce carbon monoxide emissions and ozone precursors, has contaminated drinking water and can lead to exposure by oral, inhalation, and dermal routes. To determine its dermal, oral, and inhal...

  10. INHALATION EXPOSURE TO METHYL TERT-BUTYL ETHER (MTBE) AND DIBROMOCHLOROMETHANE (DBCM) USING CONTINUOUS BREATH ANALYSIS

    The oxygenate methyl tert-butyl ether (MTBE) has been added to gasoline to help meet national ambient air quality standards in those parts of the U.S. that are non-compliant for carbon monoxide. Although MTBE has provided important health benefits in terms of reduced haza...

  11. A thermal lensing study of a photolysis of di- t-butyl peroxide

    Fuke, K.; Hasegawa, A.; Ueda, M.; Itoh, M.

    1981-11-01

    A photolysis of di- t-butyl peroxide (BOOB) was studied by using a thermal lensing technique. This technique is found to be applicable to the determination Of the rate Constants of the decay of t-butoxy radical (BO ) and the hydrogen abstraction reaction.

  12. A green-emitting CdSe/Poly(butyl acrylate) nanocomposite

    Peres, M.; Costa, L.C.; Neves, A.; Soares, M.J.; Monteiro, T.; Carvalho Esteves, de A.C.; Barros-Timmons, A.M.M.V.; Trindade, T.; Kholkin, A.; Alves, E.

    2005-01-01

    CdSe/poly(butyl acrylate) nanocomposites were synthesized by in situ miniemulsion polymerization. The hybrid nanomaterial is very stable and presents a bright green photoluminescence at 2.29 eV under ultraviolet excitation. With the excitation conditions used the intensity of the emission band keeps

  13. PHYSIOLOGICALLY BASED PHARMACOKINETIC MODEL FOR HUMAN EXPOSURES TO METHYL TERTIARY-BUTYL ETHER

    Humans can be exposed by inhalation, ingestion, or dermal absorption to methyl tertiary-butyl ether (MTBE), an oxygenated fuel additive, from contaminated water sources. The purpose of this research was to develop a physiologically based pharmacokinetic model describing in human...

  14. 2-tert-Butyl-5,6,7,8,9,10-hexahydrocyclohepta[b]indole

    Janina Wobbe

    2011-09-01

    Full Text Available 2-tert-Butyl-5,6,7,8,9,10-hexahydrocyclohepta[b]indole was synthesized by reaction of cycloheptanone and (4-tert-butylphenylhydrazine hydrochloride in the presence of sodium acetate and sulfuric acid in glacial acetic acid via Fischer indole synthesis.

  15. Application of butyl alcohol bacteria for the fermentation of nonnutritive raw materials

    Nakhamanovich, B M; Senkevich, V V; Yarovenko, V L

    1961-01-01

    Materials like corncobs after hydrolysis can be economically fermented by using bacteria which support a butyl alcohol-acetone fermentation. Best results are obtained if (NH/sub 4/)/sub 2/SO/sub 4/ and superphosphate are added to the fermentation liquor. Analyses are presnted of the hydrolzates (alcohols, formic acid, 2-furaldehyde, and reducing sugars) and of the final products.

  16. Iodine catalyzed and tertiary butyl ammonium bromide promoted p reparation of b enzoxazaphosphininyl phenylboronates

    K. R. Kishore K. Reddy,

    2009-05-01

    Full Text Available Benzoxazaphosphininyl Phenylboronates were prepared by O-Phosphorylation of potassium salt ofphenylboronic acid with cyclic phosphoromonochloridates in the presence of stoichiometric amount of Iodineand catalytic amount of tertiary butyl ammonium bromide at 50-60 °C in dry toluene.

  17. Energetic Materials Center Report--Small-Scale Safety and Thermal Testing Evaluation of Butyl Nitrate

    Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Energetic Materials Center; Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Energetic Materials Center

    2013-04-26

    Butyl Nitrate (BN) was examined by Small-Scale Safety and Thermal (SSST) Testing techniques to determine its sensitivity to impact, friction, spark and thermal exposure simulating handling and storage conditions. Under the conditions tested, the BN exhibits thermal sensitivity above 150 °C, and does not exhibit sensitive to impact, friction or spark.

  18. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (External Review Draft)

    The IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) was released for external peer review in June 2017. EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis supporting the ETB...

  19. IRIS Toxicological Review of Tert-Butyl Alcohol (Tert-Butanol) (External Review Draft)

    The IRIS Toxicological Review of tert-Butyl Alcohol (tert-Butanol) was released for external peer review in June 2017. EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis supporting ...

  20. IRIS Toxicological Review of Tert-Butyl Alcohol (Tert-Butanol) (Public Comment Draft)

    EPA is developing an Integrated Risk Information System (IRIS) assessment of tert-butyl Alcohol (tert-butanol) and has released the public comment draft assessment for public comment and external peer review. When final, the assessment will appear on the IRIS databa...

  1. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Public Comment Draft)

    In September 2016, the U.S. Environmental Protection Agency's (USEPA) released the draft Integrated Risk Information System (IRIS) Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE). Consistent with the 2013 IRIS Enhancements, draft IRIS assessments are released prior to e...

  2. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (External Review Draft, 2009)

    EPA is conducting a peer review and public comment of the scientific basis supporting the human health hazard and dose-response assessment of ethyl tertiary butyl ether (ETBE) that when finalized will appear on the Integrated Risk Information System (IRIS) database.

  3. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Interagency Science Consultation Draft)

    In September 2016, EPA released the draft IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) for public comment and discussion. The draft assessment was reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent ...

  4. Enhanced diisobutene production in the presence of methyl tertiary butyl ether

    Smith, L.A. Jr.

    1983-03-01

    In the liquid phase reaction of isobutene in the presence of resin cation exchange resins with itself in a C[sub 4] hydrocarbon stream to form dimers, the formation of higher polymers, oligomers, and co-dimer by-products is suppressed by the presence of 0.0001 to 1 mole per mole of isobutene of methyl tertiary butyl ether. 1 fig.

  5. Process Intensification of Enzymatic Fatty Acid Butyl Ester Synthesis Using a Continuous Centrifugal Contactor Separator

    Ilmi, Miftahul; Abduh, Muhammad Yusuf; Hommes, Arne; Winkelman, Jozef; Hidayat, C.; Heeres, Hero

    2018-01-01

    Fatty acid butyl esters were synthesized from sunflower oil with 1-butanol using a homogeneous Rhizomucor miehei lipase in a biphasic organic (triglyceride, 1-butanol, hexane)– water (with enzyme) system in a continuous setup consisting of a cascade of a stirred tank reactor and a continuous

  6. Voltammetric determination of butylated hydroxyanisol in biodiesel, mineral and synthetic oils using gold electrode

    Tomášková, M.; Chýlková, J.; Jehlička, V.; Navrátil, Tomáš; Šelešovská, R.

    2013-01-01

    Roč. 19, č. 2013 (2013), s. 155-172 ISSN 1211-5541 R&D Projects: GA ČR(CZ) GAP208/12/1645 Grant - others:GA ČR(CZ) GP13-21409P Program:GP Institutional support: RVO:61388955 Keywords : voltammetry * butylated hydroxyanisol * gold electrode Subject RIV: CF - Physical ; Theoretical Chemistry

  7. Subchronic toxicity studies of t-butyl alcohol in rats and mice.

    Lindamood, C; Farnell, D R; Giles, H D; Prejean, J D; Collins, J J; Takahashi, K; Maronpot, R R

    1992-07-01

    The purpose of this study was to evaluate the toxicity of t-butyl alcohol, an important commodity chemical, an additive to unleaded gasoline, and a contaminant of drinking water. Ninety-day toxicity studies were conducted in B6C3F1 mice and Fischer 344 (F344) rats of both sexes using dosed water. Dose levels of t-butyl alcohol were 0, 0.25, 0.5, 1, 2, and 4% (w/v). Lethality was observed at the 4% level of both sexes and species. Weight-gain depression was present in all dose levels of male rats; 4% female rats; 1, 2, and 4% male mice; and 2 and 4% female mice. Water consumption was increased at lower dose levels in male rats and decreased in the higher dose levels of both sexes of rats and female mice. Clinical signs in rats were ataxia in both sexes and hypoactivity in males. Clinical signs in mice were ataxia, abnormal posture, and hypoactivity. In rats, urine volumes were reduced, in association with crystalluria. Gross lesions at necropsy were urinary tract calculi, renal pelvic and ureteral dilatation, and thickening of the urinary bladder mucosa. Microscopic lesions were hyperplasia of transitional epithelia and inflammation of the urinary bladder. In male rats treated with t-butyl alcohol, microscopic renal changes were suggestive of alpha-2 mu-globulin nephropathy. No-effect levels for the urinary tract lesions were 1% in male rats and mice (803.7 mg/kg/day for the male rats and 1565.8 mg/kg/day for the male mice) and 2% in female rats and mice (1451.5 mg/kg/day for the female rats and 4362.9 mg/kg/day for the female mice). The results indicate that in rodents the urinary tract is the target organ for t-butyl alcohol toxicity, and males are more sensitive to t-butyl alcohol toxicity than females.

  8. Fracture load of complete-arch implant-supported prostheses reinforced with nylon-silica mesh: An in vitro study.

    Gonçalves, Fernanda de Cássia Papaiz; Amaral, Marina; Borges, Alexandre Luiz Souto; Gonçalves, Luiz Fernando Martins; Paes-Junior, Tarcisio José de Arruda

    2018-04-01

    Complete-arch implant-supported prostheses without a framework have a high risk of failure: a straightforward and inexpensive reinforcement material, such as nylon mesh, could improve their longevity. The purpose of this in vitro study was to evaluate a nylon-silica mesh compound on the fracture strength of acrylic resin and the fracture load of complete-arch implant-supported prostheses. Twenty-four complete mandibular arch implant-supported prostheses were divided into 2 groups according to cantilever length (molar and premolar) and subdivided into another 2 subgroups according to the presence or absence of reinforcing mesh. The specimens were submitted to a maximum load-to-fracture test in a universal testing machine, with a 100-N load cell, a 2 mm/min crosshead speed, and a spherical metal tip diameter of 4 mm at different points (molar and premolar). These were submitted to 1-way analysis of variance for repeated measurement and the post hoc Tukey multiple comparison test (α=.05). The mean maximum load ±standard deviation for the molar group was 393.4 ±95.0 N with reinforcement and 305.4 ±76.3 N without reinforcement (P=.02); and for the premolar group was 1083.3 ±283.7 N with reinforcement and 605.3 ±90.5 N without reinforcement (P=.001). Reinforcement with nylon mesh increased the mean maximum load of implant-supported complete-arch prostheses at both cantilever lengths. The cantilever to the premolar (5 mm) presented the highest maximum load values to fracture. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  9. Grafting of the 6.6 nylon with N,N-dimethylacrylamide by using ionizing radiation in the vacuum and in presence of air

    Canavel, Valdir; Kawano, Yoshio

    1997-01-01

    The present work has as objectives the obtention and characterization of graft copolymer by irradiation. The polymer used was Nylon 6.6, the monomer was N, N-dimethylacrylamide and the solvent was the formic acid. The solutions were irradiated in 60 Co source in interval dose of 0-20 kGy at two different dose rates (o,20 and 1,02 kGy/h). The results showed that the values of grafting percentage increase or decrease depending of the type of reaction: crosslinking or chain scission. The T m values decreased with the increasing of the dose in both dose rate. (author)

  10. The development of an intraruminal nylon bag technique using non-fistulated animals to assess the rumen degradability of dietary plant materials.

    Pagella, J H; Mayes, R W; Pérez-Barbería, F J; Ørskov, E R

    2018-01-01

    Although the conventional in situ ruminal degradability method is a relevant tool to describe the nutritional value of ruminant feeds, its need for rumen-fistulated animals may impose a restriction on its use when considering animal welfare issues and cost. The aim of the present work was to develop a ruminal degradability technique which avoids using surgically prepared animals. The concept was to orally dose a series of porous bags containing the test feeds at different times before slaughter, when the bags would be removed from the rumen for degradation measurement. Bags, smaller than those used in the conventional nylon bag technique, were made from woven nylon fabric, following two shape designs (rectangular flat shape, tetrahedral shape) and were fitted with one of three types of device for preventing their regurgitation. These bags were used in two experiments with individually housed non-pregnant, non-lactating sheep, as host animals for the in situ ruminal incubation of forage substrates. The bags were closed at the top edge by machine stitching and wrapped in tissue paper before oral dosing. Standard times for ruminal incubation of substrates in all of the tests were 4, 8, 16, 24, 48, 72 and 96 h before slaughter. The purpose of the first experiment was to compare the effectiveness of the three anti-regurgitation device designs, constructed from nylon cable ties ('Z-shaped', ARD1; 'double Z-shaped', ARD2; 'umbrella-shaped', ARD3), and to observe whether viable degradation curves could be generated using grass hay as the substrate. In the second experiment, three other substrates (perennial ryegrass, red clover and barley straw) were compared using flat and tetrahedral bags fitted with type ARD1 anti-regurgitation devices. Non-linear mixed-effect regression models were used to fit asymptotic exponential curves of the percentage dry matter loss of the four substrates against time of incubation in the reticulorumen, and the effect of type of anti

  11. The use of macro and micro proton beams to study the variation in PIXE yield from metal targets insulated with PTFE, glass and nylon

    Pillay, A.E.

    1999-01-01

    Proton beams of diameters of 3 mm and 3 μm, were used to observe the differences in PIXE yield from pure metal targets encapsulated with PTFE, glass (macor) and nylon. The beam energy was kept constant at 700 keV. Beam currents varied from about 200 pA with the microbeam and between 1-10 nA with the macrobeam. Considerable enhancement was observed mainly with the use of PTFE, up to about a factor of 18 with the macrobeam and 306 with the microbeam. (author)

  12. Gas chromatographic determination of Di-n-butyl phosphate in radioactive lean organic solvent of FBTR carbide fuel reprocessing

    Velavendan, P.; Ganesh, S.; Pandey, N.K.; Kamachi Mudali, U.; Natarajan, R.

    2011-01-01

    In the present work Di-n- butyl phosphate (DBP) a degraded product of Tri-n-butyl phosphate (TBP) formed by acid hydrolysis and radiolysis in the PUREX process was analyzed. Lean organic streams of different fuel burn-up FBTR carbide fuel reprocessing solution was determined by standard Gas Chromatographic technique. The method involves the conversion of non-volatile Di-n-butyl phosphate into volatile and stable derivatives by the action of diazomethane and then determined by Gas Chromatograph (GC). A calibration graph was made for DBP concentration range of 200-2000 ppm with correlation coefficient of 0.99587 and RSD 1.2 %. (author)

  13. Radiation crosslinking of poly(butyl acrylate) during polymerization and grafted copolymerization with Cr(III) crosslinked collagen

    Pietrucha, K.; Kroh, J.

    1984-01-01

    Enhanced crosslinking of synthetic polymer simultaneous with grafting and homopolymerization processes have been observed in irradiated leather tanned with Cr(III) and embedded with aqueous emulsions of butyl acrylate. Extent of poly(butyl acrylate) crosslinking during copolymerization was found to be approximately one order higher than in the case of radiation polymerization of butyl acrylate in emulsion. New method for isolation of grafted copolymer based on degradation of collagen has been developed. The extent of crosslinking was calculated from the swelling data. (author)

  14. Radiation crosslinking of poly(butyl acrylate) during polymerization and grafted copolymerization with Cr(III) crosslinked collagen

    Pietrucha, K.; Kroh, J.

    1986-01-01

    Enhanced crosslinking of synthetic polymer simultaneously with grafting and homopolymerization processes has been observed in irradiated leather tanned with Cr(III) and embedded with aqueous emulsions of butyl acrylate. The extent of poly(butyl acrylate) crosslinking during copolymerization was found to be approximately one order higher than in the case of radiation polymerization of butyl acrylate in emulsion. A new method for isolation of grafted copolymer based on degradation of collagen has been developed. The extent of crosslinking was calculated from the swelling data. (author)

  15. Estimation of the fraction of biologically active methyl tert-butyl ether degraders in a heterogeneous biomass sample

    Waul, Christopher Kevin; Arvin, Erik; Schmidt, Jens Ejbye

    2008-01-01

    The fraction of biologically active methyl tert-butyl ether degraders in reactors is just as important for prediction of removal rates as knowledge of the kinetic parameters. The fraction of biologically active methyl tert-butyl ether degraders in a heterogeneous biomass sample, taken from a packed...... bed reactor, was determined using a batch kinetic based approach. The procedure involved modeling of methyl tert-butyl ether removal rates from batch experiments followed by parameter estimations. It was estimated to be 5-14% (w/w) of the measured volatile suspended solids concentration in the reactor....

  16. Does the monofilament nylon gillnets catch double more fishes than conventional multifilament gillnets in Danube delta: myth or reality

    NAVODARU Ion

    2017-12-01

    Full Text Available The monofilament gillnets are prohibited by law for fishing in Romania. There is an untested myth among Romanian fishery stakeholders and folks that monofilament nylon gillnets have double times fishing catch than conventional multifilament gillnets. This myth provoked controversial debated between the fishermen, administrators and conservationist for the regulation purpose. To answer this dilemma in year 2014, fish fauna from Danube delta lakes was sampled with two type of research Nordic gillnets, multifilament (MF gillnets versus monofilament (MO gillnets (European Standard CEN EN14757:2015(E. Both types of fishing gears were randomly assembled from 12 mesh panels with mesh sizes of 5, 6.25, 8, 10, 12.5, 15.5, 19.5, 24, 29, 35, 43, 55 mm knot to knot. To compare fishing efficiency of two types of gillnet, 4 largest lakes inside of the Danube delta, respectively Furtuna, Merhei, Isac and Roșu lakes were sampled. The relative abundance and biomass, standardized as Catch per Unit of Fishing Effort (CPUE, expressed as number or weight per 100 m2 of gillnets per night fishing, were estimated. Accordingly with sampling test, MO gillnets caught in average more than two times more fish in abundance and/or biomass than MF gillnets. The figures are different by species, season and lake. Considering this proven of evidence, it is a policy and societal choice for future MO gillnets fishing regulation. Management regulation of MO gillnets, should consider both, socio-economic benefits and environmental impacts for sustainable use of fish resources. Simply management approach of permitting double efficient MO gillnets for more effectiveness fishing, require at least half decrease of fishing effort or capacities. That means half cutting off of the number of the fishermen permits or fishing time or number of gears or a combination of these measures, in order to maintain at least actual fishing pressure and avoid overfishing risk. Since the result refer to

  17. Detection of newly produced T and B lymphocytes by digital PCR in blood stored dry on nylon flocked swabs.

    Tessitore, Marion Vaglio; Sottini, Alessandra; Roccaro, Aldo M; Ghidini, Claudia; Bernardi, Simona; Martellosio, Giovanni; Serana, Federico; Imberti, Luisa

    2017-04-05

    A normal number of T-cell receptor excision circles (TRECs) and K-deleting recombination excision circles (KRECs) is considered a biomarker for adequate new T- and B-cell production. In newborns, detection of TRECs and KRECs by real time PCR from dried blood spotted on filter paper is used for the screening of severe immunodeficiency. In adults, elderly and during diseases, where the number of TRECs is lower than in newborns and children, a large amount of DNA and a sensitive method of amplification are necessary to identify newly produced lymphocytes. DNA was prepared from blood of 203 healthy adults (range: 18-91 years old) absorbed for 10 s on flocked swabs and let to dry, or from peripheral blood mononuclear cells. DNA was subjected to digital PCR and to well established conventional real time PCR-based method using TREC- and KREC-specific primers and probes. The number of TRECs and KRECs was expressed per mL of blood. Statistical analysis was performed by nested ANOVA, Pearson coefficient of determination, and by linear regression tests. The novel method for the storage of dried blood on nylon flocked swabs and the use of digital PCR allow quantification of TRECs and KRECs with high degree of sensitivity, specificity, accuracy, and precision. TRECs and KRECs were amplified by digital PCR in all tested blood samples, including those obtained from elderly individuals (>70 years old) and that were negative by real time PCR. Furthermore, values of TRECs and KRECs obtained by digital PCR were in the range of those acquired by real time PCR. Our findings demonstrate that DNA isolation from dried blood on flocked swabs followed by digital PCR-based analysis represents a useful tool for studying new lymphocyte production in adults and elderly individuals. This suggests the potential use of the methodology when monitoring of clinical variables is limited by the number of molecules that can be amplified and detected, such as in patients with immunodeficiency or under

  18. Synthetic phenolic antioxidants, including butylated hydroxytoluene (BHT), in resin-based dental sealants

    Wang, Wei; Kannan, Pranav; Xue, Jingchuan [Wadsworth Center, New York State Department of Health, and Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Empire State Plaza, P.O. Box 509, Albany, NY 12201-0509 (United States); Kannan, Kurunthachalam, E-mail: Kurunthachalam.kannan@health.ny.gov [Wadsworth Center, New York State Department of Health, and Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Empire State Plaza, P.O. Box 509, Albany, NY 12201-0509 (United States); Biochemistry Department, Faculty of Science, Experimental Biochemistry Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah (Saudi Arabia)

    2016-11-15

    Resin-based dental sealants (also referred to as pit-and-fissure sealants) have been studied for their contribution to bisphenol A (BPA) exposure in children. Nevertheless, little attention has been paid to the occurrence of other potentially toxic chemicals in dental sealants. In this study, the occurrence of six synthetic phenolic antioxidants (SPAs), including 2,6-di-tert-butyl-4-hydroxytoluene (BHT), 2,6-di-tert-butyl-4-(hydroxyethyl)phenol (BHT-OH), 3,5-di-tert-butyl-4-hydroxy-benzaldehyde (BHT-CHO), 2,6-di-tert-butylcyclohexa-2,5-diene-1,4-dione (BHT-Q), 3,5-di-tert-butyl-4-hydroxybenzoic acid (BHT-COOH) and 2-tert-butyl-4-methoxyphenol (BHA), was examined in 63 dental sealant products purchased from the U.S. market. BHT was found in all dental sealants at median and maximum concentrations of 56.8 and 1020 µg/g, respectively. The metabolites of BHT and BHA were detected in 39–67% of samples, at concentration ranges of butyl-4-hydroxytoluene (BHT) concentration of up to 1020 µg/g was found. • Estimated daily intake of BHT after sealant placement was up to 9.52 µg/kg bw/d. • Daily intake of BHT through dental sealant application was below the acceptable daily intake.

  19. Synthetic phenolic antioxidants, including butylated hydroxytoluene (BHT), in resin-based dental sealants

    Wang, Wei; Kannan, Pranav; Xue, Jingchuan; Kannan, Kurunthachalam

    2016-01-01

    Resin-based dental sealants (also referred to as pit-and-fissure sealants) have been studied for their contribution to bisphenol A (BPA) exposure in children. Nevertheless, little attention has been paid to the occurrence of other potentially toxic chemicals in dental sealants. In this study, the occurrence of six synthetic phenolic antioxidants (SPAs), including 2,6-di-tert-butyl-4-hydroxytoluene (BHT), 2,6-di-tert-butyl-4-(hydroxyethyl)phenol (BHT-OH), 3,5-di-tert-butyl-4-hydroxy-benzaldehyde (BHT-CHO), 2,6-di-tert-butylcyclohexa-2,5-diene-1,4-dione (BHT-Q), 3,5-di-tert-butyl-4-hydroxybenzoic acid (BHT-COOH) and 2-tert-butyl-4-methoxyphenol (BHA), was examined in 63 dental sealant products purchased from the U.S. market. BHT was found in all dental sealants at median and maximum concentrations of 56.8 and 1020 µg/g, respectively. The metabolites of BHT and BHA were detected in 39–67% of samples, at concentration ranges of butyl-4-hydroxytoluene (BHT) concentration of up to 1020 µg/g was found. • Estimated daily intake of BHT after sealant placement was up to 9.52 µg/kg bw/d. • Daily intake of BHT through dental sealant application was below the acceptable daily intake.

  20. Isothermal (vapor + liquid) equilibria and excess enthalpy data of {1-hexene + methyl butyl ether (MBE)} and {1-hexene + methyl tert-butyl ether (MTBE)} binary systems at several temperatures

    Hani, Rachida; Solimando, Roland; Negadi, Latifa; Jose, Jacques; Ait Kaci, Ahmed

    2012-01-01

    Highlights: ► Vapor pressures of (1-hexene + methyl butyl ether) or (1-hexene + methyl tert-butyl ether) are reported between (263 and 363) K. ► The two mixtures exhibit positive G E . ► Additionally, molar excess enthalpies, H E , for the two binary systems have been measured at 303.15. - Abstract: The vapor pressures of {1-hexene + methyl butyl ether (MBE)} and {1-hexene + methyl tert-butyl ether (MTBE)} binary mixtures and of the three pure components were measured by means of a static device at temperatures between (263 and 333) K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions were calculated for several constant temperatures and fitted to a third-order Redlich–Kister equation using the Barker’s method. Additionally, molar excess enthalpies, H E , for the two binary systems have been measured at 303.15 K using an isothermal flow calorimeter.

  1. HA/nylon 6,6 porous scaffolds fabricated by salt-leaching/solvent casting technique: effect of nano-sized filler content on scaffold properties

    Mehrabanian M

    2011-08-01

    Full Text Available Mehran Mehrabanian1, Mojtaba Nasr-Esfahani21Member of Young Researchers Club, Najafabad Branch, Islamic Azad University, Isfahan, Iran; 2Department of Materials Science and Engineering, Najafabad Branch, Islamic Azad University, Isfahan, IranAbstract: Nanohydroxyapatite (n-HA/nylon 6,6 composite scaffolds were produced by means of the salt-leaching/solvent casting technique. NaCl with a distinct range size was used with the aim of optimizing the pore network. Composite powders with different n-HA contents (40%, 60% for scaffold fabrication were synthesized and tested. The composite scaffolds thus obtained were characterized for their microstructure, mechanical stability and strength, and bioactivity. The microstructure of the composite scaffolds possessed a well-developed interconnected porosity with approximate optimal pore size ranging from 200 to 500 µm, ideal for bone regeneration and vascularization. The mechanical properties of the composite scaffolds were evaluated by compressive strength and modulus tests, and the results confirmed their similarity to cortical bone. To characterize bioactivity, the composite scaffolds were immersed in simulated body fluid for different lengths of time and results monitored by scanning electron microscopy and energy dispersive X-ray microanalysis to determine formation of an apatite layer on the scaffold surface.Keywords: scaffold, nanohydroxyapatite, nylon 6,6, salt-leaching/solvent casting, bioactivity

  2. Conductivity and touch-sensor application for atomic layer deposition ZnO and Al:ZnO on nylon nonwoven fiber mats

    Sweet, William J.; Oldham, Christopher J.; Parsons, Gregory N.

    2015-01-01

    Flexible electronics and wearable technology represent a novel and growing market for next generation devices. In this work, the authors deposit conductive zinc oxide films by atomic layer deposition onto nylon-6 nonwoven fiber mats and spun-cast films, and quantify the impact that deposition temperature, coating thickness, and aluminum doping have on the conductivity of the coated substrates. The authors produce aluminum doped zinc oxide (AZO) coated fibers with conductivity of 230 S/cm, which is ∼6× more conductive than ZnO coated fibers. Furthermore, the authors demonstrate AZO coated fibers maintain 62% of their conductivity after being bent around a 3 mm radius cylinder. As an example application, the authors fabricate an “all-fiber” pressure sensor using AZO coated nylon-6 electrodes. The sensor signal scales exponentially under small applied force (<50 g/cm 2 ), yielding a ∼10 6 × current change under 200 g/cm 2 . This lightweight, flexible, and breathable touch/force sensor could function, for example, as an electronically active nonwoven for personal or engineered system analysis and diagnostics

  3. Portal Hypertension Secondary to Spontaneous Arterio-Portal Venous Fistulas: Transcatheter Arterial Embolization with n-Butyl Cyanoacrylate and Microcoils

    Yamagami, Takuji; Nakamura, Toshiyuki; Nishimura, Tsunehiko

    2000-01-01

    We report a 73-year-old man with recurrent variceal bleeding due to portal hypertension caused by multiple intrahepatic arterio-portal venous fistulas, which were successfully occluded by embolization with n-butyl cyanoacrylate and micro-coils

  4. Influence Of Initiator Types And Emulsion Polymerization Techniques To Particle Size Of Copolymerization Styrene-Butyl Acrylate-Methyl Methacrylate

    Ariyanti Sarwono

    2008-11-01

    Full Text Available Influence of initiator types and emulsion polymerization techniques to particle size of copolymerization styrene-butyl acrylate-methyl methacrylate. Copoly(styrene/butyl acrylic/methyl methacrylic was prepared by emulsion polymerization method. This paper describes effect of insiator types i.e. ammonium persulfate (APS, hydrogen peroxide, ters-butyl peroxide (TBHP, initiator redox (H2O2/ascorbic acid and polymerization techniques i.e. batch and semicontinue to particle size distribution of copoly(styrene/butyl acrylic/methyl methacrylic. Initiator TBHP and H2O2 could not initiate copolymerization properly, but initiator APS and redox initiate copolymerization with batch and semi continue techniques could well perform. The higher concentration of APS, the greater particle size of the copolymer, but the copolymer is polymodal. Initiator redox (H2O2/ascorbic acid produced greater particle size than initiator redox (ascorbic acid/ H2O2.

  5. ATOM TRANSFER RADICAL POLYMERIZATION OF N-BUTYL METHACRYLATE IN AQUEOUS DISPERSED SYSTEMS: A MINIEMULSION APPROACH. (R826735)

    Ultrasonication was applied in combination with a hydrophobe for the copper-mediated atom transfer radical polymerization of n-butyl methacrylate in an aqueous dispersed system. A controlled polymerization was successfully achieved, as demonstrated by a linear correlation between...

  6. Ion chromatographic determination of Di-n-butyl phosphate in degraded organic solvent

    Velavendan, P.; Pandey, N.K.; Kamachi Mudali, U.; Natarajan, R.

    2011-01-01

    In the present work a method for the determination of Di-n-butyl phosphate in organic streams using Ion Chromatography technique is developed and described here. The method involves the separation of Di-n-butyl phosphate (DBP) from 30% TBP-NPH (Tri-n-butylphosphate diluted in Normal Paraffin Hydrocarbon) and uranium/nitric acid matrix by an extraction of DBP in alkaline medium and subsequent ion-exchange separation in ion chromatography column followed by suppressed conductivity detection. Direct determination of DBP in lean/loaded organic solvent will lead to in accurate determination of DBP due to organic interference. DBP is quantified to lower limit of 1 ppm with 3% RSD. The results obtained with ion chromatographic technique are compared with those obtained by standard gas chromatographic technique. The developed method is much faster and total analysis can be completed within two hours. (author)

  7. Preparation of poly(acrylonitrile-butyl acrylate) gel electrolyte for lithium-ion batteries

    Tian Zheng; He Xiangming; Pu Weihua; Wan Chunrong; Jiang Changyin

    2006-01-01

    Poly(acrylonitrile-butyl acrylate) gel polymer electrolyte was prepared for lithium ion batteries. The preparation started with synthesis of poly(acrylonitrile-butyl acrylate) by radical emulsion polymerization, followed by phase inversion to produce microporous membrane. Then, the microporous gel polymer electrolytes (MGPEs) was prepared with the microporous membrane and LiPF 6 in ethylene carbonate/diethyl carbonate. The dry microporous membrane showed a fracture strength as high as 18.98 MPa. As-prepared gel polymer electrolytes presented ionic conductivity in excess of 3.0 x 10 -3 S cm -1 at ambient temperature and a decomposition voltage over 6.6 V. The results showed that the as-prepared gel polymer electrolytes were promising materials for Li-ion batteries

  8. Crystal structure of 1-butyl-2,3-dimethylimidazolium dicarba-7,8-nido-undecaborate

    M. J. Klemes

    2015-03-01

    Full Text Available In the title molecular salt, C9H17N2+·C2H12B9−, the carborane cage has a bridging B—H—B bond on the open B3C2 face. The butyl side chain of the cation adopts an extended conformation [C—C—C—C = 179.6 (1°]. In the crystal, the imidazolium ring is almost coplanar with the open face of the carborane anion. The cations stack in the [010] direction and the dihedral angle between the imidazolium rings of adjacent cations is 68.45 (6°. The butyl chains extend into the space between carborane anions.

  9. The influence of n-butyl mercaptan on acrylic compounds obtained winder γ-gamma radiation

    Ribeiro, Marcos S.; Parra, Duclerc F.; Lugao, Ademar B.

    2013-01-01

    The chain transfer agents play a key role in the production of polymers, as they allow better control of their molecular weight, among other functions. For this reason we performed this study to perform an analysis on the influence of n-butyl mercaptan in the reaction of compounds of ethyl methacrylate by varying the density and shrinkage of the samples. In the present study can be seen that n-butyl mercaptan, acts as transfer agent, which influences the reaction kinetics of composite acrylic, since it presence in the compound increased average density and contraction average. It is also possible to minimize the variability of the compound density, even if they are altered. Final products with improved properties homogeneously could be obtained. (author)

  10. Preparation of poly(acrylonitrile-butyl acrylate) gel electrolyte for lithium-ion batteries

    Tian Zheng [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); He Xiangming [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China)]. E-mail: hexm@tsinghua.edu.cn; Pu Weihua [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Wan Chunrong [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Jiang Changyin [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China)

    2006-10-25

    Poly(acrylonitrile-butyl acrylate) gel polymer electrolyte was prepared for lithium ion batteries. The preparation started with synthesis of poly(acrylonitrile-butyl acrylate) by radical emulsion polymerization, followed by phase inversion to produce microporous membrane. Then, the microporous gel polymer electrolytes (MGPEs) was prepared with the microporous membrane and LiPF{sub 6} in ethylene carbonate/diethyl carbonate. The dry microporous membrane showed a fracture strength as high as 18.98 MPa. As-prepared gel polymer electrolytes presented ionic conductivity in excess of 3.0 x 10{sup -3} S cm{sup -1} at ambient temperature and a decomposition voltage over 6.6 V. The results showed that the as-prepared gel polymer electrolytes were promising materials for Li-ion batteries.

  11. Recanalization of Splenic Artery Aneurysm After Transcatheter Arterial Embolization Using N-Butyl Cyanoacrylate

    Matsumoto, Keiji; Ushijima, Yasuhiro; Tajima, Tsuyoshi; Nishie, Akihiro; Hirakawa, Masakazu; Ishigami, Kousei; Yamaji, Yukiko; Honda, Hiroshi

    2010-01-01

    A 65-year-old woman who had been diagnosed as having microscopic polyangiitis developed sudden abdominal pain and entered a state of shock. Abdominal CT showed massive hemoperitoneum, and emergent angiography revealed a ruptured splenic artery aneurysm. After direct catheterization attempts failed due to tortuous vessels and angiospasm, transcatheter arterial embolization using an n-butyl cyanoacrylate (NBCA)-lipiodol mixture was successfully performed. Fifty days later, the patient developed sudden abdominal pain again. Repeated angiography demonstrated recanalization of the splenic artery and splenic artery aneurysm. This time, the recanalized aneurysm was embolized using metallic coils with the isolation method. Physicians should keep in mind that recanalization can occur after transcatheter arterial embolization using N-butyl cyanoacrylate, which has been used as a permanent embolic agent.

  12. Effect of di-butyl phosphate on flash point of PUREX solvent

    Srivastav, Ravi Kant; Kumar, Shekhar; Balasubramonian, S.; Kamachi Mudali, U.; Natarajan, R.

    2015-01-01

    30% Tri-n-butyl phosphate (TBP) in a aliphatic diluent is used as a solvent for PUREX process. This diluent is essentially equivalent to commercial dodecane. The radiolytic and acidic degradation of TBP forms di-butyl phosphate (DBP) which is detrimental to the performance of the solvent during nuclear fuel reprocessing operations. To study the possible effect of DBP on the flashpoint of PUREX solvent, synthetic solutions were made by adding DBP and flashpoints of resultant mixtures were determined with an automatic flashpoint tester as per ASTM procedures. Experimental results indicated virtually no effect of DBP on flash point of PUREX solvent in the concentration ranges of 0-16 g/L DBP. (author)

  13. Synthesis and characterization of tris[butyl-(1-methyl-3-phenyl-propyl-dithiocarbamato]-cobalt(III seskvitoluene

    TIBOR SABO

    2002-02-01

    Full Text Available A new bidentate ligand butyl-(1-methyl-3-phenyl-propyl-dithiocarbamate (bmFpdtc was prepared, as the sodium salt. In the reaction of hexaaminecobalt(III chloride with NabmFpdtc, the corresponding tris[butyl-(1-methyl-3-phenyl-propyl-dithiocarbamato]cobalt(III, [Co(bmFpdtc3] complex was prepared. The complex was characterized by elemental analysis, infrared, electronic absorption, 1H and 13C-NMR spectroscopy.

  14. Synthesis and characterization of tris[butyl-(1-methyl-3-phenyl-propyl)-dithiocarbamato]-cobalt(III) seskvitoluene

    TIBOR SABO; ISMET M. HODZIC; SRECKO R. TRIFUNOVIC; VESNA M. DJINOVIC; GORAN N. KALUDJEROVIC

    2002-01-01

    A new bidentate ligand butyl-(1-methyl-3-phenyl-propyl)-dithiocarbamate (bmFpdtc) was prepared, as the sodium salt. In the reaction of hexaaminecobalt(III) chloride with NabmFpdtc, the corresponding tris[butyl-(1-methyl-3-phenyl-propyl)-dithiocarbamato]cobalt(III), [Co(bmFpdtc)3] complex was prepared. The complex was characterized by elemental analysis, infrared, electronic absorption, 1H and 13C-NMR spectroscopy.

  15. Polyvinylpolypyrrolidone-Supported Boron Trifluoride; Highly Efficient Catalyst for the Synthesis of N-tert-Butyl Amides

    Masoud Mokhtary

    2012-01-01

    Full Text Available Highly efficient method for the preparation of N-tert-butyl amides by reaction of nitriles with tert-butyl acetate is described using polyvinylpolypyrrolidone-supported boron trifluoride (PVPP-BF3 at 70°C in good to excellent yields. Selective amidation of benzonitrile in the presence of acetonitrile was also achieved. polyvinylpolypyrrolidone-boron trifluoride complex shows non-corrosive and stable solid catalyst elevated Lewis acid property.

  16. On the interaction of molybdenum cyanide complexes with hydroperoxide of tertiary butyl

    Vretsena, N.B.; Nikipanchuk, M.V.; Chernyak, B.I.

    1979-01-01

    Conducted is investigation of interaction of potassium dioxotetracyanomolybdate (4) K 4 [MoO 2 (CN) 4 ], potassium oxotetracyanomolybdate (2) K 4 [MoO(CN) 4 ] and potassium tetracyanomolybdate K 4 [Mo(CN) 4 ] in CCl 4 and hydroperoxide of tertiary butyl medium, (HPTB). Shown is the process complex mechanism which leads to molybdenum oxidation in complexes and also to coordination and HPTB decomposition. Calculated are parameters of complex formation process of molybdenum with HPTB cyanide complexes

  17. Temperature effect on tert-butyl alcohol (TBA biodegradation kinetics in hyporheic zone soils

    Sims Ronald C

    2007-09-01

    Full Text Available Abstract Background Remediation of tert-butyl alcohol (TBA in subsurface waters should be taken into consideration at reformulated gasoline contaminated sites since it is a biodegradation intermediate of methyl tert-butyl ether (MTBE, ethyl tert-butyl ether (ETBE, and tert-butyl formate (TBF. The effect of temperature on TBA biodegradation has not been not been published in the literature. Methods Biodegradation of [U 14C] TBA was determined using hyporheic zone soil microcosms. Results First order mineralization rate constants of TBA at 5°C, 15°C and 25°C were 7.84 ± 0.14 × 10-3, 9.07 ± 0.09 × 10-3, and 15.3 ± 0.3 × 10-3 days-1, respectively (or 2.86 ± 0.05, 3.31 ± 0.03, 5.60 ± 0.14 years-1, respectively. Temperature had a statistically significant effect on the mineralization rates and was modelled using the Arrhenius equation with frequency factor (A and activation energy (Ea of 154 day-1 and 23,006 mol/J, respectively. Conclusion Results of this study are the first to determine mineralization rates of TBA for different temperatures. The kinetic rates determined in this study can be used in groundwater fate and transport modelling of TBA at the Ronan, MT site and provide an estimate for TBA removal at other similar shallow aquifer sites and hyporheic zones as a function of seasonal change in temperature.

  18. High-pressure phase behavior of propyl lactate and butyl lactate in supercritical carbon dioxide

    Cho, Dong Woo; Shin, Jungin; Shin, Moon Sam; Bae, Won; Kim, Hwayong

    2012-01-01

    Highlights: ► The phase behavior of propyl lactate and butyl lactate in scCO 2 was measured. ► Experimental data were correlated by the PR-EOS. ► The critical constants were estimated by the three group contribution methods. ► Acentric factor was estimated by the Lee–Kesler method. ► The Nannoolal–Rarey and Lee–Kesler method shows the best correlation results. - Abstract: Lactate esters synthesized with lactic acid and ester are used as solvents and reactants in various industries, including agricultural chemistry, pharmaceuticals, electronics, and fine chemicals. Among lactate esters, high purity propyl lactate and butyl lactate are used to produce fine chemicals and in the synthesis of chiral intermediates for use in pesticides and drugs. However, distillation for the removal of propyl lactate and butyl lactate alters or degenerates products due the high boiling points of these two lactate esters. This problem can be solved by supercritical fluid extraction (SCFE) at lower temperatures. SCFE process requires high-pressure phase behavior data on CO 2 and lactates for its design and operation. In this study, high-pressure phase behavior of propyl lactate and butyl lactate in CO 2 was measured from (323.2 to 363.2) K using a variable-volume view cell apparatus. Experimental data were well correlated by the Peng–Robinson equation of state using the van der Waals one-fluid mixing rules. The critical constants were estimated by the Joback method, the Constantinou–Gani method, and the Nannoolal–Rarey method. Acentric factor was estimated by the Lee–Kesler method.

  19. Tri-n-butyl phosphate - the universal solvent for the nuclear fuel cycle

    Naylor, A.; Eccles, H.

    1988-01-01

    Tri-n-butyl phosphates (TBP) is now Widely used in the processes of solvent extraction, especially in those, used in nuclear fuel cycle. Problems, related with actinide separation and purification, can be solved easily by accurate sampling of diluent, concentration and purification degree of a solvent, aqueous phase acidity and temperature. Physical and chemical properties of TBP, mechanism of actinide solvent extraction, TBP hydrolysis and radiolysis are considered

  20. Preparation and Properties of Triethoxyvinylsilane-Modified Styrene - Butyl Acrylate Emulsion Copolymers

    NAGHASH, Hamid Javaherian; KARIMZADEH, Akram; MOMENI, Ahmad Reza; MASSAH, Ahmad Reza; ALIAN, Hamid

    2014-01-01

    The copolymers of triethoxyvinylsilane (TEVS) with styrene (St), butyl acrylate (BA), and methacrylic acid (MAA) were prepared by emulsion polymerization. The copolymerization was carried out by using auxiliary agents at 90 °C in the presence of potassium peroxodisulfate (KPS) as the initiator. Nonylphenol ethylene oxide -- 40 units (NP-40) and sodium lauryl sulfoacetate (SLSA) were used as nonionic and anionic emulsifiers, respectively. The resulting copolymers were characterized b...

  1. Osmotic and apparent molar properties of binary mixtures alcohol+1-butyl-3-methylimidazolium trifluoromethanesulfonate ionic liquid

    Emilio Gomez; Noelia Simón; Ángeles Domínguez; Maria Eugénia Macedo

    2013-01-01

    In this work, physical properties (densities and speeds of sound) for the binary systems {1-propanol, or 2-propanol, or 1-butanol, or 2-butanol, or 1-pentanol + 1-butyl-3-methylimidazolium trifluoromethanesulfonate} were experimentally measured from T = (293.15 to 323.15) K and at atmospheric pressure. These data were used to calculate the apparent molar volume and apparent molar isentropic compression which were fitted to a Redlich-Meyer type equation. This fit was used to obtain the corresp...

  2. {2,6-Bis[(di-tert-butyl-phosphino)-methyl]-phenyl}chloridonickel(II).

    Boro, Brian J; Dickie, Diane A; Goldberg, Karen I; Kemp, Richard A

    2008-09-20

    In the title compound, [Ni(C(24)H(43)P(2))Cl], the Ni atom adopts a distorted square-planar geometry, with the P atoms of the 2,6-bis-[(di-tert-butyl-phosphino)meth-yl]phenyl ligand trans to one another. The P-Ni-P plane is twisted out of the plane of the aromatic ring by 21.97 (6)°.

  3. Synthesis, Characterization and Evaluation of the Transformations in Hibiscus sabdariffa-graft-poly(butyl acrylate

    B. S. Kaith

    2008-01-01

    Full Text Available Different reaction parameters for the graft copolymerization of butyl acrylate onto Hibiscus sabdariffa fiber were optimized. Graft copolymers thus obtained were subjected to characterization using XRD, TGA, DTA, SEM and FTIR techniques and were evaluated for physio-chemical changes in the behavior. The percentage crystallinity and crystallinity index were found to decrease with increase in grafting while there was reduction in moisture absorption and increase in chemical, thermal resistance of the graft copolymers.

  4. 1-[(E-2-(5-tert-Butyl-2-hydroxyphenyldiazen-1-yl]naphthalen-2-ol

    Hassiba Bougueria

    2014-02-01

    Full Text Available The non-H atoms of the title compound, C20H20N2O2, is located on a mirror plane except two methyl groups of the tert-butyl group. Intramolecular N—H...O hydrogen bonds exist between the hydroxy and diazenyl groups. In the crystal, molecules are linked by weak C—H...O hydrogen bonds into supramolecular chains running along the a-axis direction.

  5. Vinyl Acetate/butyl acrylate/acrylate Research of Ternary Soap-free Emulsion Polymerization

    Xiao Li-guang

    2016-01-01

    Full Text Available Through the vinyl acetate/butyl acrylate/acrylic acrylic emulsion preparation without soap vinegar, with solid content, gel, emulsion stability and film forming properties and tensile strength as the main index to study the effect of raw materials on the properties of emulsion. Through the infrared spectrometer soap-free emulsion for microscopic analysis research. Study of the ternary soap-free vinegar acrylic emulsion with good performance.

  6. Simultaneous determination of triacetin, acetic ether, butyl acetate and amorolfine hydrochloride in amorolfine liniment by HPLC.

    Gao, Yuan; Li, Li; Zhang, Jianjun; Shu, Wenjuan; Gao, Liqiong

    2012-04-01

    A simple, rapid, specific and precise reversed-phase high-performance liquid chromatographic method was developed for simultaneous estimation of triacetin, acetic ether, butyl acetate and amorolfine in marketed pharmaceutical liniment. Chromatographic separation was performed on a Shimadzu VP-ODS C(18) column using the mixture of citric acid-hydrochloric acid-sodium hydrate buffer (pH 3.0), acetonitrile and methanol (32:30:38) as the mobile phase at a flow rate of 1.0 mL/min with UV-detection at 215 nm. The method separated the four components simultaneously in less than 10 min. The validation of the method was performed with respect to specificity, linearity, accuracy, and precision. The calibration curves were linear in the range of 35.1-81.9 μ/mL for triacetin, 431.1-1005.9 μ/mL for acetic ether, 167.0-389.7 μ/mL for butyl acetate and 151.0-352.3 μ/mL for amorolfine. The mean 100% spiked recovery for triacetin, acetic ether, butyl acetate and amorolfine is 99.43 ± 0.42, 101.5 ± 1.09, 101.4 ± 1.02 and 100.8 ± 0.69, respectively. The intra-day and inter-day relative standard deviation values were liniment.

  7. Catalytic Upgrading of Biomass-Derived Furfuryl Alcohol to Butyl Levulinate Biofuel over Common Metal Salts

    Lincai Peng

    2016-09-01

    Full Text Available Levulinate ester has been identified as a promising renewable fuel additive and platform chemical. Here, the use of a wide range of common metal salts as acid catalysts for catalytic upgrading of biomass-derived furfuryl alcohol to butyl levulinate was explored by conventional heating. Both alkali and alkaline earth metal chlorides did not lead effectively to the conversion of furfuryl alcohol, while several transition metal chlorides (CrCl3, FeCl3, and CuCl2 and AlCl3 exhibited catalytic activity for the synthesis of butyl levulinate. For their sulfates (Cr(III, Fe(III, Cu(II, and Al(III, the catalytic activity was low. The reaction performance was correlated with the Brønsted acidity of the reaction system derived from the hydrolysis/alcoholysis of cations, but was more dependent on the Lewis acidity from the metal salts. Among these investigated metal salts, CuCl2 was found to be uniquely effective, leading to the conversion of furfuryl alcohol to butyl levulinate with an optimized yield of 95%. Moreover, CuCl2 could be recovered efficiently from the resulting reaction mixture and remained with almost unchanged catalytic activity in multiple recycling runs.

  8. Final report of the addendum to the safety assessment of n-butyl alcohol as used in cosmetics.

    McLain, Valerie C

    2008-01-01

    n-Butyl Alcohol is a primary aliphatic alcohol historically used as a solvent in nail care cosmetic products, but new concentration of use data indicate that it also is being used at low concentrations in eye makeup, personal hygiene, and shaving cosmetic products. n-Butyl Alcohol has been generally recognized as safe for use as a flavoring substance in food and appears on the 1982 Food and Drug Administration (FDA) list of inactive ingredients for approved prescription drug products. n-Butyl Alcohol can be absorbed through the skin, lungs, and gastrointestinal tract. n-Butyl Alcohol may be formed by hydrolysis of butyl acetate in the blood, but is rapidly oxidized. The single oral dose LD(50) of n-Butyl Alcohol for rats was 0.79 to 4.36 g/kg. The dermal LD(50) for rabbits was 4.2 g/kg. Inhalation toxicity studies in humans demonstrate sensory irritation of the upper respiratory tract, but only at levels above 3000 mg/m(3). Animal studies demonstrate intoxication, restlessness, ataxia, prostration, and narcosis. Exposures of rats to levels up to 4000 ppm failed to produce hearing defects. High concentrations of n-Butyl Alcohol vapors can be fatal. Ocular irritation was observed for n-Butyl alcohol at 0.005 ml of a 40% solution. The behavioral no-effect dose for n-Butyl Alcohol injected subcutaneously (s.c.) was 120 mg/kg. Fetotoxicity has been demonstrated, but only at maternally toxic levels (1000 mg/kg). No significant behavioral or neurochemical effects were seen in offspring following either maternal or paternal exposure to 3000 or 6000 ppm. n-Butyl Alcohol was not mutagenic in Ames tests, did not induce sister-chromatid exchange or chromosome breakage in chick embryos or Chinese hamster ovary cells, did not induce micronuclei formation in V79 Chinese hamster cells, did not have any chromosome-damaging effects in a mouse micronucleus test, and did not impair chromosome distribution in the course of mitosis. Clinical testing of n-Butyl Alcohol for

  9. A COMPARATIVE STUDY BETWEEN SURGICAL OUTCOME OF PATIENT’S OWN BLOOD VS. 10-0 NYLON FOR CONJUNCTIVAL AUTOGRAFTING IN PTERYGIUM EXCISION

    Ayush Mahendra

    2016-04-01

    Full Text Available CONTEXT (BACKGROUND Pterygium is a frequently occurring progressive ocular surface disorder which is a fleshy triangular wing shaped growth, encroaching from conjunctiva on cornea. Pterygium is frequent in hot, dry, dusty environment and prevalence is 0.3% to 29%. Surgical removal is main treatment for pterygium. The recurrence rate after pterygium surgery varies according to type of surgery. Various surgical modalities tried like simple excision, bare sclera technique, amniotic membrane transplantation and conjunctival autografting. AIM To compare surgical outcome of patient’s own blood Vs 10-0 Nylon for conjunctival autografting in pterygium excision. SETTINGS AND DESIGN It is a prospective randomised interventional control trial, with a sample size of minimum 30 patients in each group studied in a tertiary care hospital from Oct. 2013 to Dec. 2015. METHODS AND MATERIAL Out of 63 patients who underwent pterygium excision, patient’s own blood was used in 32 patients (Group A and 10-0 Nylon suture was used in 31 patients (Group B for conjunctival autografting. All patients were followed up regularly on postoperative day 1, 8, 30, 90 and 180. Variables for postoperative assessment were pain, watering, irritation, redness, graft displacement, graft loss and recurrence. STATISTICAL ANALYSIS Statistical analysis was performed using SPSS 13.0 (SPSS, Chicago. Outcome variables between the two groups were compared using the non-parametric Mann–Whitney U Test. RESULTS The mean surgical time of group B (31.48±6.15 min is significantly high as compared to group A (19.71±5.13 min with p<0.001. The regression analysis revealed that except surgery type, no other variable had significant impact on the duration of surgery. Postoperative symptoms are less in group A as compared to group B. Group B showed two recurrences whereas no recurrence was seen in group A. CONCLUSIONS Conjunctival autografting by patient’s own blood is better than 10-0 Nylon

  10. Structural evolution in the isothermal crystallization process of the molten nylon 10/10 traced by time-resolved infrared spectral measurements and synchrotron SAXS/WAXD measurements

    Tashiro, Kohji; Nishiyama, Asami; Tsuji, Sawako; Hashida, Tomoko; Hanesaka, Makoto; Takeda, Shinichi; Weiyu, Cao; Reddy, Kummetha Raghunatha; Masunaga, Hiroyasu; Sasaki, Sono; Takata, Masaki; Ito, Kazuki

    2009-01-01

    The structural evolution in the isothermal crystallization process of nylon 10/10 from the melt has been clarified concretely on the basis of the time-resolved infrared spectral measurement as well as the synchrotron wide-angle and small-angle X-ray scattering measurements. Immediately after the temperature jump from the melt to the crystallization point, the isolated domains consisting of the hydrogen-bonded random coils were formed in the melt, as revealed by Guinier plot of SAXS data and the infrared spectral data. With the passage of time these domains approached each other with stronger correlation as analyzed by Debye-Bueche equation. These domains transformed finally to the stacked crystalline lamellae, in which the conformationally-regularized methylene segments of the CO sides were connected each other by stronger intermolecular hydrogen bonds to form the crystal lattice.

  11. Dynamic mechanical analysis of binary and ternary polymer blends based on nylon copolymer/EPDM rubber and EPM grafted maleic anhydride compatibilizer

    2007-10-01

    Full Text Available The dynamic mechanical properties such as storage modulus, loss modulus and damping properties of blends of nylon copolymer (PA6,66 with ethylene propylene diene (EPDM rubber was investigated with special reference to the effect of blend ratio and compatibilisation over a temperature range –100°C to 150°C at different frequencies. The effect of change in the composition of the polymer blends on tanδ was studied to understand the extent of polymer miscibility and damping characteristics. The loss tangent curve of the blends exhibited two transition peaks, corresponding to the glass transition temperature (Tg of individual components indicating incompatibility of the blend systems. The morphology of the blends has been examined by using scanning electron microscopy. The Arrhenius relationship was used to calculate the activation energy for the glass transition of the blends. Finally, attempts have been made to compare the experimental data with theoretical models.

  12. Combined Use of Clips and Nylon Snare (“Tulip-Bundle” as a Rescue Endoscopic Bleeding Control in a Mallory-Weiss Syndrome

    Hrvoje Ivekovic

    2014-01-01

    Full Text Available Mallory-Weiss syndrome (MWS accounts for 6–14% of all cases of upper gastrointestinal bleeding. Prognosis of patients with MWS is generally good, with a benign course and rare recurrence of bleeding. However, no strict recommendations exist in regard to the mode of action after a failure of primary endoscopic hemostasis. We report a case of an 83-year-old male with MWS and rebleeding after the initial endoscopic treatment with epinephrine and clips. The final endoscopic control of bleeding was achieved by a combined application of clips and a nylon snare in a “tulip-bundle” fashion. The patient had an uneventful postprocedural clinical course and was discharged from the hospital five days later. To the best of our knowledge, this is the first case report showing the “tulip-bundle” technique as a rescue endoscopic bleeding control in the esophagus.

  13. Combined use of clips and nylon snare ("tulip-bundle") as a rescue endoscopic bleeding control in a mallory-weiss syndrome.

    Ivekovic, Hrvoje; Radulovic, Bojana; Jankovic, Suzana; Markos, Pave; Rustemovic, Nadan

    2014-01-01

    Mallory-Weiss syndrome (MWS) accounts for 6-14% of all cases of upper gastrointestinal bleeding. Prognosis of patients with MWS is generally good, with a benign course and rare recurrence of bleeding. However, no strict recommendations exist in regard to the mode of action after a failure of primary endoscopic hemostasis. We report a case of an 83-year-old male with MWS and rebleeding after the initial endoscopic treatment with epinephrine and clips. The final endoscopic control of bleeding was achieved by a combined application of clips and a nylon snare in a "tulip-bundle" fashion. The patient had an uneventful postprocedural clinical course and was discharged from the hospital five days later. To the best of our knowledge, this is the first case report showing the "tulip-bundle" technique as a rescue endoscopic bleeding control in the esophagus.

  14. Silver Clear Nylon Dressing is Effective in Preventing Radiation-Induced Dermatitis in Patients With Lower Gastrointestinal Cancer: Results From a Phase III Study

    Niazi, Tamim M. [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada); Vuong, Te, E-mail: tvuong@jgh.mcgill.ca [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada); Azoulay, Laurant [Department of Epidemiology, Jewish General Hospital, McGill University (Canada); Marijnen, Corrie [Department of Clinical Oncology, Leiden University Medical Center, Amsterdam (Netherlands); Bujko, Kryzstof [Department of Radiotherapy, The Maria Sklodowska-Curie Memorial Cancer Centre, Warsaw (Poland); Nasr, Elie [Department of Radiation Oncology, Hotel-Dieu de France Hospital (Lebanon); Lambert, Christine; Duclos, Marie; Faria, Sergio; David, Marc [Department of Radiation Oncology, Montreal-General-Hospital, McGill University, Montreal (Canada); Cummings, Bernard [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto (Canada)

    2012-11-01

    Purpose: For patients with anal canal and advanced rectal cancer, chemoradiation therapy is a curative modality or an important adjunct to surgery. Nearly all patients treated with chemoradiation experience some degree of radiation-induced dermatitis (RID). Prevention and effective treatment of RID, therefore, is of considerable clinical relevance. The present phase III randomized trial compared the efficacy of silver clear nylon dressing (SCND) with that of standard skin care for these patients. Methods and Materials: A total of 42 rectal or anal canal cancer patients were randomized to either a SCND or standard skin care group. SCND was applied from Day 1 of radiation therapy (RT) until 2 weeks after treatment completion. In the control arm, sulfadiazine cream was applied at the time of skin dermatitis. Printed digital photographs taken 2 weeks prior to, on the last day, and two weeks after the treatment completion were scored by 10 blinded readers, who used the common toxicity scoring system for skin dermatitis. Results: The radiation dose ranged from 50.4 to 59.4 Gy, and there were no differences between the 2 groups. On the last day of RT, when the most severe RID occurs, the mean dermatitis score was 2.53 (standard deviation [SD], 1.17) for the standard and 1.67 (SD, 1.2; P=.01) for the SCND arm. At 2 weeks after RT, the difference was 0.39 points in favor of SCND (P=.39). There was considerable intraclass correlation among the 10 observers. Conclusions: Silver clear nylon dressing is effective in reducing RID in patients with lower gastrointestinal cancer treated with combined chemotherapy and radiation treatment.

  15. Study of epithelial differentiation and protein expression of keratinocyte-mesenchyme stem cell co-cultivation on electrospun nylon/B. vulgaris extract composite scaffold

    Hosseinzadeh, Simzar [School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Soleimani, Masoud [Department of Hematology, Faculty of Medical Sciences, TarbiatModares University, Tehran (Iran, Islamic Republic of); Vossoughi, Manuchehr [Chemical and Petroleum Engineering Department, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Ranjbarvan, Parviz [Department of Tissue Engineering, School of Advanced Medical Technologies, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Hamedi, Shokoh [Department of Persian Pharmacy, School of Persian and Complementary Medicine, Mashhad University of Medical Sciences, Mashhad (Iran, Islamic Republic of); Zamanlui, Soheila [Tissue Engineering and Regenerative Medicine Institute, Tehran Central Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Mahmoudifard, Matin, E-mail: mahmodifard@mehr.sharif.edu [Institute for Nanoscience and Nanotechnology, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Nanotechnology and Tissue Engineering Department, Stem Cell Technology Research Center, Tehran (Iran, Islamic Republic of)

    2017-06-01

    Employing of the composite electrospun scaffold containing herbal extract in conjugation with co-culturing of cells can open up new window to the design of efficient biomaterials for skin tissue regeneration. Here, we introduce the synergistic effect of composite electrospun nanofibrous scaffold of nylon66 loaded with Beta vulgaris (B. vulgaris) (extract of beet roots, a plants whose widely used in Iranian folk medicine as wound healing medicine) and co-culture of mesenchymal stem-cells (MSCs)-human keratinocyte (H-keratino) differentiation towards epithelial lineage. In vitro biocompatibility was examined through MTT assay and epithelial differentiation checked by real-time PCR and immunocytochemistry (ICC) assay after co-culturing of MSCs and H-keratino on proposed scaffold. Significant enhancement in cell proliferation was detected after cell culturing on the composite type of electrospun scaffold containing B. vulgaris. Moreover, after 14 days of co-culturing process, gene expression results revealed that both composite and non-composite nylon66 electrospun scaffold promote epithelial differentiation compared to mono-cell culturing of H-keratino in terms of several markers as Cytokeratin 10, Cytokeratin 14 and Involucrin and ICC of some dermal proteins like Cytokeratin 14 and Loricrin. To the best of our knowledge, findings of this study will introduce new way for the generation of novel biomaterials for the development of current skin tissue engineering. - Highlights: • New way for the generation of novel biomaterials for the development of current skin tissue engineering. • Fabrication of novel composite scaffold containing Beta vulgaris through electrospinning • Synergistic effect was found on epithelial differentiation through co-culture of keratinocyte and MSC on proposed composite NFM.

  16. Study of epithelial differentiation and protein expression of keratinocyte-mesenchyme stem cell co-cultivation on electrospun nylon/B. vulgaris extract composite scaffold

    Hosseinzadeh, Simzar; Soleimani, Masoud; Vossoughi, Manuchehr; Ranjbarvan, Parviz; Hamedi, Shokoh; Zamanlui, Soheila; Mahmoudifard, Matin

    2017-01-01

    Employing of the composite electrospun scaffold containing herbal extract in conjugation with co-culturing of cells can open up new window to the design of efficient biomaterials for skin tissue regeneration. Here, we introduce the synergistic effect of composite electrospun nanofibrous scaffold of nylon66 loaded with Beta vulgaris (B. vulgaris) (extract of beet roots, a plants whose widely used in Iranian folk medicine as wound healing medicine) and co-culture of mesenchymal stem-cells (MSCs)-human keratinocyte (H-keratino) differentiation towards epithelial lineage. In vitro biocompatibility was examined through MTT assay and epithelial differentiation checked by real-time PCR and immunocytochemistry (ICC) assay after co-culturing of MSCs and H-keratino on proposed scaffold. Significant enhancement in cell proliferation was detected after cell culturing on the composite type of electrospun scaffold containing B. vulgaris. Moreover, after 14 days of co-culturing process, gene expression results revealed that both composite and non-composite nylon66 electrospun scaffold promote epithelial differentiation compared to mono-cell culturing of H-keratino in terms of several markers as Cytokeratin 10, Cytokeratin 14 and Involucrin and ICC of some dermal proteins like Cytokeratin 14 and Loricrin. To the best of our knowledge, findings of this study will introduce new way for the generation of novel biomaterials for the development of current skin tissue engineering. - Highlights: • New way for the generation of novel biomaterials for the development of current skin tissue engineering. • Fabrication of novel composite scaffold containing Beta vulgaris through electrospinning • Synergistic effect was found on epithelial differentiation through co-culture of keratinocyte and MSC on proposed composite NFM

  17. Biosynthesis of the Nylon 12 Monomer, ω-Aminododecanoic Acid with Novel CYP153A, AlkJ, and ω-TA Enzymes.

    Ahsan, Md Murshidul; Jeon, Hyunwoo; P Nadarajan, Saravanan; Chung, Taeowan; Yoo, Hee-Wang; Kim, Byung-Gee; Patil, Mahesh D; Yun, Hyungdon

    2018-04-01

    Bioplastics are derived from renewable biomass sources, such as vegetable oils, cellulose, and starches. An important and high-performance member of the bioplastic family is Nylon 12. The biosynthesis of ω-amino dodecanoic acid (ω-AmDDA), the monomer of Nylon 12 from vegetable oil derivatives is considered as an alternative to petroleum-based monomer synthesis. In this study, for the production of ω-AmDDA from dodecanoic acid (DDA), the cascade of novel P450 (CYP153A), alcohol dehydrogenase (AlkJ), and ω-transaminase (ω-TA) is developed. The regioselective ω-hydroxylation of 1 mM DDA with near complete conversion (>99%) is achieved using a whole-cell biocatalyst co-expressing CYP153A, ferredoxin reductase and ferredoxin. When the consecutive biotransformation of ω-hydroxy dodecanoic acid (ω-OHDDA) is carried out using a whole-cell biocatalyst co-expressing AlkJ and ω-TA, 1.8 mM ω-OHDDA is converted into ω-AmDDA with 87% conversion in 3 h. Finally, when a one-pot reaction is carried out with 2 mM DDA using both whole-cell systems, 0.6 mM ω-AmDDA is produced after a 5 h reaction. The results demonstrated the scope of the potential cascade reaction of novel CYP153A, AlkJ, and ω-TA for the production of industrially important bioplastic monomers, amino fatty acids, from FFAs. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Silver Clear Nylon Dressing is Effective in Preventing Radiation-Induced Dermatitis in Patients With Lower Gastrointestinal Cancer: Results From a Phase III Study

    Niazi, Tamim M.; Vuong, Te; Azoulay, Laurant; Marijnen, Corrie; Bujko, Kryzstof; Nasr, Elie; Lambert, Christine; Duclos, Marie; Faria, Sergio; David, Marc; Cummings, Bernard

    2012-01-01

    Purpose: For patients with anal canal and advanced rectal cancer, chemoradiation therapy is a curative modality or an important adjunct to surgery. Nearly all patients treated with chemoradiation experience some degree of radiation-induced dermatitis (RID). Prevention and effective treatment of RID, therefore, is of considerable clinical relevance. The present phase III randomized trial compared the efficacy of silver clear nylon dressing (SCND) with that of standard skin care for these patients. Methods and Materials: A total of 42 rectal or anal canal cancer patients were randomized to either a SCND or standard skin care group. SCND was applied from Day 1 of radiation therapy (RT) until 2 weeks after treatment completion. In the control arm, sulfadiazine cream was applied at the time of skin dermatitis. Printed digital photographs taken 2 weeks prior to, on the last day, and two weeks after the treatment completion were scored by 10 blinded readers, who used the common toxicity scoring system for skin dermatitis. Results: The radiation dose ranged from 50.4 to 59.4 Gy, and there were no differences between the 2 groups. On the last day of RT, when the most severe RID occurs, the mean dermatitis score was 2.53 (standard deviation [SD], 1.17) for the standard and 1.67 (SD, 1.2; P=.01) for the SCND arm. At 2 weeks after RT, the difference was 0.39 points in favor of SCND (P=.39). There was considerable intraclass correlation among the 10 observers. Conclusions: Silver clear nylon dressing is effective in reducing RID in patients with lower gastrointestinal cancer treated with combined chemotherapy and radiation treatment.

  19. Optimal Cultivation Time for Yeast and Lactic Acid Bacteria in Fermented Milk and Effects of Fermented Soybean Meal on Rumen Degradability Using Nylon Bag Technique

    S. Polyorach

    2016-09-01

    Full Text Available The objectives of this study were to determine an optimal cultivation time for populations of yeast and lactic acid bacteria (LAB co-cultured in fermented milk and effects of soybean meal fermented milk (SBMFM supplementation on rumen degradability in beef cattle using nylon bag technique. The study on an optimal cultivation time for yeast and LAB growth in fermented milk was determined at 0, 4, 8, 24, 48, 72, and 96 h post-cultivation. After fermenting for 4 days, an optimal cultivation time of yeast and LAB in fermented milk was selected and used for making the SBMFM product to study nylon bag technique. Two ruminal fistulated beef cattle (410±10 kg were used to study on the effect of SBMFM supplementation (0%, 3%, and 5% of total concentrate substrate on rumen degradability using in situ method at incubation times of 0, 2, 4, 6, 12, 24, 48, and 72 h according to a Completely randomized design. The results revealed that the highest yeast and LAB population culture in fermented milk was found at 72 h-post cultivation. From in situ study, the soluble fractions at time zero (a, potential degradability (a+b and effective degradability of dry matter (EDDM linearly (p<0.01 increased with the increasing supplemental levels and the highest was in the 5% SBMFM supplemented group. However, there was no effect of SBMFM supplement on insoluble degradability fractions (b and rate of degradation (c. In conclusion, the optimal fermented time for fermented milk with yeast and LAB was at 72 h-post cultivation and supplementation of SBMFM at 5% of total concentrate substrate could improve rumen degradability of beef cattle. However, further research on effect of SBMFM on rumen ecology and production performance in meat and milk should be conducted using in vivo both digestion and feeding trials.

  20. Rapid analysis of effluents generated by the dairy industry for fat determination by preconcentration in nylon membranes and attenuated total reflectance infrared spectroscopy measurement.

    Moliner Martínez, Y; Muñoz-Ortuño, M; Herráez-Hernández, R; Campíns-Falcó, P

    2014-02-01

    This paper describes a new approach for the determination of fat in the effluents generated by the dairy industry which is based on the retention of fat in nylon membranes and measurement of the absorbances on the membrane surface by ATR-IR spectroscopy. Different options have been evaluated for retaining fat in the membranes using milk samples of different origin and fat content. Based on the results obtained, a method is proposed for the determination of fat in effluents which involves the filtration of 1 mL of the samples through 0.45 µm nylon membranes of 13 mm diameter. The fat content is then determined by measuring the absorbance of band at 1745 cm(-1). The proposed method can be used for the direct estimation of fat at concentrations in the 2-12 mg/L interval with adequate reproducibility. The intraday precision, expressed as coefficients of variation CVs, were ≤ 11%, whereas the interday CVs were ≤ 20%. The method shows a good tolerance towards conditions typically found in the effluents generated by the dairy industry. The most relevant features of the proposed method are simplicity and speed as the samples can be characterized in a few minutes. Sample preparation does not involve either additional instrumentation (such as pumps or vacuum equipment) or organic solvents or other chemicals. Therefore, the proposed method can be considered a rapid, simple and cost-effective alternative to gravimetric methods for controlling fat content in these effluents during production or cleaning processes. © 2013 Published by Elsevier B.V.

  1. Forensic analysis of tertiary-butyl alcohol (TBA) detections in a hydrocarbon-rich groundwater basin.

    Quast, Konrad W; Levine, Audrey D; Kester, Janet E; Fordham, Carolyn L

    2016-04-01

    Tertiary-butyl alcohol (TBA), a high-production volume (HPV) chemical, was sporadically detected in groundwater and coalbed methane (CBM) wells in southeastern Colorado's hydrocarbon-rich Raton Basin. TBA concentrations in shallow water wells averaged 75.1 μg/L, while detections in deeper CBM wells averaged 14.4 μg/L. The detection of TBA prompted a forensic investigation to try to identify potential sources. Historic and recent data were reviewed to determine if there was a discernable pattern of TBA occurrence. Supplemental samples from domestic water wells, monitor wells, CBM wells, surface waters, and hydraulic fracturing (HF) fluids were analyzed for TBA in conjunction with methyl tertiary-butyl ether (MTBE) and ethyl tertiary-butyl ether (ETBE), proxies for evidence of contamination from reformulated gasoline or associated oxygenates. Exploratory microbiological sampling was conducted to determine if methanotrophic organisms co-occurred with TBA in individual wells. Meaningful comparisons of historic TBA data were limited due to widely varying reporting limits. Mapping of TBA occurrence did not reveal any spatial patterns or physical associations with CBM operations or contamination plumes. Additionally, TBA was not detected in HF fluids or surface water samples. Given the widespread use of TBA in industrial and consumer products, including water well completion materials, it is likely that multiple diffuse sources exist. Exploratory data on stable isotopes, dissolved gases, and microbial profiling provide preliminary evidence that methanotrophic activity may be producing TBA from naturally occurring isobutane. Reported TBA concentrations were significantly below a conservative risk-based drinking water screening level of 8000 μg/L derived from animal toxicity data.

  2. n-Alkane assimilation and tert-butyl alcohol (TBA) oxidation capacity in Mycobacterium austroafricanum strains.

    Lopes Ferreira, Nicolas; Mathis, Hugues; Labbé, Diane; Monot, Frédéric; Greer, Charles W; Fayolle-Guichard, Françoise

    2007-06-01

    Mycobacterium austroafricanum IFP 2012, which grows on methyl tert-butyl ether (MTBE) and on tert-butyl alcohol (TBA), the main intermediate of MTBE degradation, also grows on a broad range of n-alkanes (C2 to C16). A single alkB gene copy, encoding a non-heme alkane monooxygenase, was partially amplified from the genome of this bacterium. Its expression was induced after growth on n-propane, n-hexane, n-hexadecane and on TBA but not after growth on LB. The capacity of other fast-growing mycobacteria to grow on n-alkanes (C1 to C16) and to degrade TBA after growth on n-alkanes was compared to that of M. austroafricanum IFP 2012. We studied M. austroafricanum IFP 2012 and IFP 2015 able to grow on MTBE, M. austroafricanum IFP 2173 able to grow on isooctane, Mycobacterium sp. IFP 2009 able to grow on ethyl tert-butyl ether (ETBE), M. vaccae JOB5 (M. austroaafricanum ATCC 29678) able to degrade MTBE and TBA and M. smegmatis mc2 155 with no known degradation capacity towards fuel oxygenates. The M. austroafricanum strains grew on a broad range of n-alkanes and three were able to degrade TBA after growth on propane, hexane and hexadecane. An alkB gene was partially amplified from the genome of all mycobacteria and a sequence comparison demonstrated a close relationship among the M. austroafricanum strains. This is the first report suggesting the involvement of an alkane hydroxylase in TBA oxidation, a key step during MTBE metabolism.

  3. A coarse-grained polarizable force field for the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate

    Zeman, Johannes; Uhlig, Frank; Smiatek, Jens; Holm, Christian

    2017-12-01

    We present a coarse-grained polarizable molecular dynamics force field for the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIm][PF6]). For the treatment of electronic polarizability, we employ the Drude model. Our results show that the new explicitly polarizable force field reproduces important static and dynamic properties such as mass density, enthalpy of vaporization, diffusion coefficients, or electrical conductivity in the relevant temperature range. In situations where an explicit treatment of electronic polarizability might be crucial, we expect the force field to be an improvement over non-polarizable models, while still profiting from the reduction of computational cost due to the coarse-grained representation.

  4. TRANS-ARTERIAL EMBOLIZATION WITH N-BUTYL CYANOACRYLATE GLUE FOR RENAL BLEEDING: Case Report

    Benny Young

    2014-08-01

    Full Text Available Background: The objectivity in management of renal bleeding is to preserve a significant renal parenchyma tissue and prevent associated morbidities like anemic shock or renal impairment from substantial nephron demise or obstructed uropathy. Trans-arterial embolization therapy by interventional radiology offers a high success rate with potential of reserving normal renal tissue. The selection material for renal arterial embolization largely depends on vasculature anatomy and end-point of procedure. N-butyl cyanoacrylate glue in our experience is applied in lesion supplied by small size of end-artery. 

  5. Inhibition Effect of 1-Butyl-4-Methylpyridinium Tetrafluoroborate on the Corrosion of Copper in Phosphate Solutions

    Scendo, M.; Uznanska, J.

    2011-01-01

    The influence of the concentration of 1-Butyl-4-methylpyridinium tetrafluoroborate (4MBPBF4) as ionic liquid (IL) on the corrosion of copper in 0.5 M P O 4 3 − solutions of pH 2 and 4 was studied. The research involved electrochemical polarization method, and scanning electron microscopy (SEM) technique. The results obtained showed that the inhibition efficiency of corrosion of copper increases with an increase in the concentration of 4MBPBF4 but decreases with increasing temperature. The the...

  6. Synchrotron Photoionization Investigation of the Oxidation of Ethyl tert-Butyl Ether.

    Winfough, Matthew; Yao, Rong; Ng, Martin; Catani, Katherine; Meloni, Giovanni

    2017-02-23

    The oxidation of ethyl tert-butyl ether (ETBE), a widely used fuel oxygenated additive, is investigated using Cl atoms as initiators in the presence of oxygen. The reaction is carried out at 293, 550, and 700 K. Reaction products are probed by a multiplexed chemical kinetics photoionization mass spectrometer coupled with the synchrotron radiation produced at the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory. Products are identified on the basis of mass-to-charge ratio, ionization energies, and shape of photoionization spectra. Reaction pathways are proposed together with detected primary products.

  7. Mechanism of n-butyl acrylate sensitization action in radiation vulcanization of natural rubber latex

    Sabharwal, S.; Chaudhari, C.V.; Bhardwaj, Y.K.; Majali, A.B.; Das, T.N.

    1996-01-01

    In order to understand the role of n-butyl acrylate (nBA) in radiation vulcanization of natural rubber latex, pulse radiolysis technique has been utilized to study the reactions of the transient species produced by reaction of OH . , e- aq and H . atoms with nBA in aqueous solutions. The results show that transients produced by reaction of e- aq with nBA alone are capable of propagating the polymerization reaction and enhance the vulcanization process. These results have been further confirmed by studying the effect of electron scavengers on the vulcanization behaviour of natural rubber latex in presence of nBA. (author). 3 refs., 3 figs

  8. Percutaneous Direct Puncture Embolization with N-butyl-cyanoacrylate for High-flow Priapism

    Tokue, Hiroyuki, E-mail: tokue@s2.dion.ne.jp; Shibuya, Kei [Gunma University Hospital, Department of Diagnostic and Interventional Radiology (Japan); Ueno, Hiroyuki [Isesaki Municipal Hospital, Department of Radiology (Japan); Tokue, Azusa; Tsushima, Yoshito [Gunma University Hospital, Department of Diagnostic and Interventional Radiology (Japan)

    2016-09-15

    There are many treatment options in high-flow priapism. Those mentioned most often are watchful waiting, Doppler-guided compression, endovascular highly selective embolization, and surgery. We present a case of high-flow priapism in a 57-year-old man treated by percutaneous direct puncture embolization of a post-traumatic left cavernosal arteriovenous fistula using N-butyl-cyanoacrylate. Erectile function was preserved during a 12-month follow-up. No patients with percutaneous direct puncture embolization for high-flow priapism have been reported previously. Percutaneous direct puncture embolization is a potentially useful and safe method for management of high-flow priapism.

  9. Positron annihilation analysis of epoxy/hydroxyl terminated butyl nitrile rubber (EP/HTBN) system

    Zeng Minfeng; Chen Ning; Ji Genzhong; Sun Xudong; Zhao Rener; Xiao Huiquan; Qi Chenze; Wang Baoyi

    2007-01-01

    The free volume properties of epoxy/hydroxyl terminated butyl nitrile rubber (EP/HTBN) have been studied by means of positron annihilation technique. The toughness effect is found to be correlated with the content of HTBN and the free volume properties of the EP/HTBN interfaces. When the content of HTBN component is 5%, the free volume size in the interface is close to that of EP, and the toughness effect is strong. But with further addition of HTBN, holes with big size free volume are formed in the interface, and the toughness effect is limited. (authors)

  10. High monomer content batch microemulsion polymerization of butyl acrylate initiated with gamma ray

    Chen Jun [Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China)]. E-mail: chjun04@mail.ustc.edu.cn; Zhang Zhicheng [Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China)]. E-mail: zczhang@ustc.edu.cn

    2007-05-15

    Radiation polymerization of butyl acrylate was performed in a microemulsion stabilized with a mixture of sodium of 12-acryloxy-9-octadecenoic acid and sodium dodecyl sulfate in a weight ratio of 2 at room temperature. BA content in microemulsion can be successfully improved up to 40 wt% with low surfactant concentration (lower than 10 wt%). The resulted stable, translucent microlatex contain particles with average diameter from 28.1 to 38.1 nm with different monomer content. Particle size depends on the dose rate and surfactant concentration. Effects of monomer content and dose rate on the maximum polymerization rate are discussed.

  11. High Solid Contents Copoly (Styrene/Butyl Acrylate-Cloisite 30B Nanocomposites

    M. Mirzataheri

    2013-03-01

    Full Text Available Higher solid contents (20 % and 40 % nanocomposites of poly (styrene-co-butyl acrylate including higher content of Cloisite 30B (7 wt% and 10 wt % were prepared via miniemulsion polymerization. Stability of the final latexes proved outstanding combination of polymerization procedure and surfactants. Morphological studies revealed by TEM, SAX and XRD showed three structures of core-shell, armored and individual dispersion of clay layers within the polymer particles. The effect of Cloisite 30B content on the barrier properties presents excellent and wide use of these films for packaging and nanocoatings industries.

  12. Synthesis and quality control of sup(99m)Tc-p-butyl IDA

    Zmbova, B.; Konstantinovska-Djokic, D.; Tadzer, I.

    1985-01-01

    A procedure is described for synthesis of p-butyl IDA and for identification of the product by i.r. and NMR spectroscopy and by chemical analysis. A method for preparing this compound by ''instant'' technique and for its labelling with sup(99m)Tc is also given, as well as a procedure for control of the chemical and biological properties of the radiopharmaceutical. Radiochemical study shows a high labelling yield of 95%. Investigation of the biodistribution proves that this preparation is a good hepatobiliary reagent, suitable for use in investigation of the liver functions and for quantitative visualization of the hepatobiliary system. (author)

  13. Overview of technologies for removal of methyl tert-butyl ether (MTBE) from water.

    Levchuk, Irina; Bhatnagar, Amit; Sillanpää, Mika

    2014-04-01

    Wide use of methyl tert-butyl ether (MTBE) as fuel oxygenates leads to worldwide environment contamination with this compound basically due to fuel leaks from storage or pipelines. Presence of MTBE in drinking water is of high environmental and social concern. Existing methods for MTBE removal from water have a number of limitations which can be possibly overcome in the future with use of emerging technologies. This work aims to provide an updated overview of recent developments in technologies for MTBE removal from water. Copyright © 2014. Published by Elsevier B.V.

  14. Study on separation of methanol-butyl methylether-1-chlorobutane system

    Zhang Weijiang; Cao Tianhong

    2006-01-01

    The separation of mixture plays an important role in chemical, petrochemical, medical biochemical industries and environmental protection engineering. Liquid mixture with azeotropic phenomenon cannot be separated by conventional distillation as well as extractive distillation. But the combination of extraction and distillation can be effective for them. This paper includes many experiments with the ternary mixture of methanol butyl methyl ether and 1-chlorobytane, which shows that the system is not ternary azeotrope and can be separated by the combination of extraction and rectification using water as extractive solvent. (authors)

  15. (N-Benzyl-N-ethyl­dithio­carbamato)di-tert-butyl­chloridotin(IV)

    Abdul Muthalib, Amirah Faizah; Baba, Ibrahim; Mohamed Tahir, Mohamed Ibrahim; Tiekink, Edward R. T.

    2011-01-01

    The SnIV atom in the title diorganotin dithio­carbamate, [Sn(C4H9)2Cl(C10H12NS2)], is penta­coordinated by an asymmetrically coordinating dithio­carbamate ligand, a Cl and two C atoms of the Sn-bound tert-butyl groups. The resulting C2ClS2 donor set defines a coordination geometry inter­mediate between square pyramidal and trigonal bipyramidal with a slight tendency towards the former. In the crystal structure, C—H⋯π contacts link centrosymmetrically related mol­ecules into dimeric aggregates...

  16. Di-tert-butyl­chlorido(N,N-dibenzyl­dithio­carbamato)tin(IV)

    Abdul Muthalib, Amirah Faizah; Baba, Ibrahim; Mohamed Tahir, Mohamed Ibrahim; Tiekink, Edward R. T.

    2011-01-01

    The SnIV atom in the title diorganotin dithio­carbamate, [Sn(C4H9)2(C15H14NS2)Cl], is penta­coordinated by an asymmetrically coordinating dithio­carbamate ligand, a Cl atom and two C atoms of the Sn-bound tert-butyl groups. The resulting C2ClS2 donor set defines a coordination geometry inter­mediate between square pyramidal and trigonal bipyramidal with a slight tendency towards the former. PMID:21522304

  17. Di-tert-butyl-chlorido(N,N-dibenzyl-dithio-carbamato)tin(IV).

    Abdul Muthalib, Amirah Faizah; Baba, Ibrahim; Mohamed Tahir, Mohamed Ibrahim; Tiekink, Edward R T

    2011-02-26

    The Sn(IV) atom in the title diorganotin dithio-carbamate, [Sn(C(4)H(9))(2)(C(15)H(14)NS(2))Cl], is penta-coordinated by an asymmetrically coordinating dithio-carbamate ligand, a Cl atom and two C atoms of the Sn-bound tert-butyl groups. The resulting C(2)ClS(2) donor set defines a coordination geometry inter-mediate between square pyramidal and trigonal bipyramidal with a slight tendency towards the former.

  18. (N-Benzyl-N-ethyl­dithio­carbamato)di-tert-butyl­chloridotin(IV)

    Abdul Muthalib, Amirah Faizah; Baba, Ibrahim; Mohamed Tahir, Mohamed Ibrahim; Tiekink, Edward R. T.

    2011-01-01

    The SnIV atom in the title diorganotin dithio­carbamate, [Sn(C4H9)2Cl(C10H12NS2)], is penta­coordinated by an asymmetrically coordinating dithio­carbamate ligand, a Cl and two C atoms of the Sn-bound tert-butyl groups. The resulting C2ClS2 donor set defines a coordination geometry inter­mediate between square pyramidal and trigonal bipyramidal with a slight tendency towards the former. In the crystal structure, C—H⋯π contacts link centrosymmetrically related mol­ecules into dimeric aggregates. PMID:21522295

  19. (N-Benzyl-N-ethyl-dithio-carbamato)di-tert-butyl-chloridotin(IV).

    Abdul Muthalib, Amirah Faizah; Baba, Ibrahim; Mohamed Tahir, Mohamed Ibrahim; Tiekink, Edward R T

    2011-02-26

    The Sn(IV) atom in the title diorganotin dithio-carbamate, [Sn(C(4)H(9))(2)Cl(C(10)H(12)NS(2))], is penta-coordinated by an asymmetrically coordinating dithio-carbamate ligand, a Cl and two C atoms of the Sn-bound tert-butyl groups. The resulting C(2)ClS(2) donor set defines a coordination geometry inter-mediate between square pyramidal and trigonal bipyramidal with a slight tendency towards the former. In the crystal structure, C-H⋯π contacts link centrosymmetrically related mol-ecules into dimeric aggregates.

  20. Comparative substoichiometric extraction of zinc with potassium salts of ethyl, propyl, butyl, pentyl and benzyl xanthates

    Chandrasekhar Reddy, P.; Rangamannar, P.

    1995-01-01

    The comparative extractability of zinc with potassium salts of ethyl, propyl, butyl, pentyl, and benzyl xanthates from the pH range of 3.5-9.0 into chloroform has been studied, employing a sensitive and rapid substoichiometric radiochemical method. The extent of reproducibility was tested in each case. The effect of associated ions on the extraction was studied. The amount of zinc present in the standard solutions was determined employing each xanthate separately. The zinc content present in geological water samples in and around Tirupati was determined by the method developed and compared with the values obtained by Atomic Absorption Spectrophotometry. (author) 4 refs.; 3 figs.; 4 tabs

  1. Comparative substoichiometric extraction of cadmium with potassium salts of ethyl, propyl, butyl, pentyl and benzyl xanthates

    Chandrasekhar Reddy, P.; Rangamannar, B.

    1995-01-01

    A comparative study of the extractability of cadmium with potassium salts of ethyl, propyl, butyl, pentyl and benzyl xanthates into chloroform and a mixture of 1:4 pyridine and ethyl acetate from pH 1-7 buffers and sodium formate media, respectively, has been carried out employing an accurate and highly sensitive substoichiometric radiochemical method. The effect of foreign ions on the extractability was studied. The method developed was utilized for the determination of cadmium content in standard as well as in geological water samples. (author) 4 refs.; 5 figs.; 3 tabs

  2. Degradation of a recalcitrant xenobiotic compound: methyl tert-butyl ether (MTBE) metabolism by mycobacterium austroafricanum; Degradation d'un compose xenobiotique recalcitrant: metabolisme du methyl tert-butyl ether (MTBE) par mycobacterium austroafricanum IFP 2012

    Francois, A

    2002-11-01

    Methyl tert-butyl ether (MTBE) is introduced up to 15% (vol/vol) in gasoline in order to obtain a good octane number and to prevent carbon monoxide emissions. However, as a consequence of storage tanks leakage, MTBE became one of the major pollutants of aquifers because of its very low biodegradability. The present study aimed at investigating the biodegradation of MTBE by Mycobacterium austroafricanum IFP 2012. The MTBE metabolic pathway was partially elucidated owing to the identification of some intermediates (tert-butyl formate (TBF), tert-butyl alcohol (TBA), a-hydroxy-isobutyric acid and acetone) and some enzymatic activities (MTBE/TBA monooxygenase (non hemic and inducible), TBF esterase, 2-propanol: NDMA oxidoreductase and another monooxygenase involved in acetone degradation). The involvement of TBF and the requirement of cobalt could be explanations for the low natural attenuation of MTBE; whereas the methoxy group does not seem to be implicated. (author)

  3. Degradation of a recalcitrant xenobiotic compound: methyl tert-butyl ether (MTBE) metabolism by mycobacterium austroafricanum; Degradation d'un compose xenobiotique recalcitrant: metabolisme du methyl tert-butyl ether (MTBE) par mycobacterium austroafricanum IFP 2012

    Francois, A.

    2002-11-01

    Methyl tert-butyl ether (MTBE) is introduced up to 15% (vol/vol) in gasoline in order to obtain a good octane number and to prevent carbon monoxide emissions. However, as a consequence of storage tanks leakage, MTBE became one of the major pollutants of aquifers because of its very low biodegradability. The present study aimed at investigating the biodegradation of MTBE by Mycobacterium austroafricanum IFP 2012. The MTBE metabolic pathway was partially elucidated owing to the identification of some intermediates (tert-butyl formate (TBF), tert-butyl alcohol (TBA), a-hydroxy-isobutyric acid and acetone) and some enzymatic activities (MTBE/TBA monooxygenase (non hemic and inducible), TBF esterase, 2-propanol: NDMA oxidoreductase and another monooxygenase involved in acetone degradation). The involvement of TBF and the requirement of cobalt could be explanations for the low natural attenuation of MTBE; whereas the methoxy group does not seem to be implicated. (author)

  4. Gamma-Ray-Initiated Graft Copolymerization on the Surface of Nylon Fibers and in the Inner Layers of Cellulosic Fibers; Amorcage par rayons gamma de la formation de copolymeres greffes a la surface de fibres de nylon et dans les couches internes de fibres cellulosiques; Sopolimerizatsionnoe narashchivanie na poverkhnosti nejlonovogo volokna i vo vnutrennikh sloyakh tsellyuloznykh volokon pod dejstviem gamma-izluchenij; Copolimerizacion por injerto radioinducida en la superficie de fibras de nylon y en las capas internas de fibras celulosicas

    Okamura, S; Iwasaki, T; Kobayashi, Y; Hayashi, K

    1960-07-15

    Crosslinks are formed as a result of the irradiation of nylon fibers in an atmosphere of nitrogen whereas degradation takes place on irradiation in air. Changes taking place on irradiation were studied by measurements of the viscosities of the irradiated fibers in sulphuric acid solutions. The tensile properties were also examined in air. If nylon fiber is irradiated in nitrogen, dipped in an aqueous solution of acrylamide and irradiated, grafting takes place only on the surface. When the preliminary irradiation is carried out in air, grafting takes place within the fiber. The location of the graft polymer is obtained by dyeing the fiber. The extent of grafting of cellulose fibers with styrene from methanol solution is very considerably increased if the cellulose fibers are swollen in a 5 - 10% solution of formamide in methanol. The effect of the concentrations of formamide and styrene in the methanolic solutions were studied and maximum grafting was found to occur at 5% formamide and 70% styrene concentrations. At dose rates of the order of 10{sup 5}r./h. it was found that the rate of grafting was diffusion controlled. (author) [French] L'irradiation de fibres de nylon dans une atmosphere d'azote provoque une reticulation tandis que l'irradiation dans l'air entraine une degradation des polymeres. Les auteurs ont etudie les modifications qui se produisent sous l'effet de l'irradiation, en mesurant la viscosite des fibres irradiees dans des solutions d'acide sulfurique. Ils ont aussi examine la resistance a la tension dans l'air. Si la fibre de nylon est d'abord irradiee dans l'azote, plongee dans une solution aqueuse d'acrylamide puis irradiee de nouveau, le greffage ne se produit qu'en surface. Lorsque l'irradiation preliminaire est faite dans l'air, le greffage se produit a l'interieur de la fibre. On localise le polymere greffe en colorant la fibre. Le greffage des fibres cellulosiques en presence de styrolene dissous dans du methanol augmente considerablement

  5. Working-up sugar-beet molasses in the acetone-butyl alcohol plants in Poland

    Logotkin, I S; Zaritskii, I M

    1959-01-01

    The basic setup common to all Polish acetone and butanol plants is the addition of rye or wheat meal to the fermentation. A culture of Clostridium acetobutylicum, after spore formation, is mixed in a special apparatus with the meal, where it is kept for 18 hours at 37/sup 0/ and then treated with molasses; a culture is prepared which is used later in the fermentor. Independently a mixture of meal and molasses is mixed in an autoclave with H/sub 2/O, sterilized, and cooled. The resulting mash is mixed in the fermentor with the culture mentioned, where the fermentation liberates CO/sub 2/ and hydrogen which are recovered. The mixture is then heated, distilled, and rectified, where, in addition to slops, the desired products are obtained. The Polish plants figure that for each long ton of sugar contained in the molasses they recover butyl alcohol 178.0, acetone 83.7, and ethanol 7.3kg, and they use in addition to the molasses and bacilli cultures 58.4 tons of steam and 16 kg of NaOH long ton of the acetone-butyl alcohol mixture recovered.

  6. SIRT1 exhibits antioxidative effects in HT22 cells induced by tert-butyl alcohol.

    Ma, Junxiang; Song, Dongmei; Zhang, Yuanyuan; Chen, Li; Zhang, Shixuan; Jia, Jiaxin; Chen, Tian; Guo, Caixia; Tian, Lin; Gao, Ai; Niu, Piye

    2018-02-01

    Tertiary butyl alcohol (TBA) is a principal metabolite of methyl tertiary-butyl ether (MTBE), a common pollutant worldwide in the ground or underground water, which is found to produce nervous system damage. Nevertheless, few data regarding the effects of TBA has been reported. Studies indicated that oxidative stress plays a pivotal role in MTBE neurotoxic mechanism. Sirtuin 1 (SIRT1) has been reported to exert a neuroprotective effect on various neurologic diseases via resistance to oxidative stress by deacetylating its substrates. In this study, we examined levels of oxidative stress after exposure to TBA for 6 h in HT22 cells and HT22 cells with SIRT1 silencing (transfected with SIRT1 siRNA) or high expression (preconditioned with agonists SRT1720). We found that TBA activated oxidative stress by increasing generation of intracellular reactive oxygen species (ROS), malondialdehyde (MDA) and Oxidized glutathione (GSSG), and decreasing contents of superoxide dismutase (SOD) and glutathione reductase (GSH). In additional, levels of TBA-induced oxidative stress were aggravated when SIRT1 silenced but alleviated when SIRT1 enhanced. Our study indicated that SIRT1 mitigated oxidative stress induced by TBA. © 2017 Wiley Periodicals, Inc.

  7. Sutureless vascular anastomoses by N-butyl-2 cyanoacrylate adhesive: an experimental animal study.

    Saba, D; Yilmaz, M; Yavuz, H; Noyan, S; Avci, B; Ercan, A; Ozkan, H; Cengiz, M

    2007-01-01

    The purpose of this animal study was to find out whether sutureless anastomoses using N-butyl-2-cyanoacrylate were effective in the suppression of neointimal hyperplasia or not. Ten male adult mongrel dogs were used in this animal study. The animals were randomly divided into a control group (n = 5) and a study group (n = 5). The study group underwent sutureless anastomoses using N-buthyl-2-cyanoacrylate adhesive. Infrarenal aortoaortic graft was interposed using polytetrafluoroethylene. In the study group, the mean intimal thickness at the proximal anastomosis was 27.4 +/- 1.94 microm and 27.4 +/- 1.51 microm at the distal anastomosis. In the control group, the mean intimal thickness was 138.4 +/- 5.02 mum at the proximal anastomosis and 67.6 +/- 6.42 microm at the distal anastomosis. Intimal thickness at the proximal and distal anastomoses in the control group was significantly (p anastomoses using with N-butyl-2-cyanoacrylate adhesive might be a good alternative to conventional suture technique. Copyright 2007 S. Karger AG, Basel.

  8. Anodic oxidation of chloride ions in 1-butyl-3-methyl-limidazolium tetrafluoroborate ionic liquid

    Zhang, Qibo; Hua, Yixin; Wang, Rui

    2013-01-01

    Highlights: • The anodic oxidation of Cl − in BMIMBF 4 is electrochemically irreversible with diffusion controlled. • The oxidation of Cl − in BMIMBF 4 is more likely to form tri-chloride ion, Cl 3 − but not chlorine, Cl 2 . • The minute amount of Cl 2 detected after electrolysis forms according to the equilibrium of Cl 2 + Cl − ⇌ Cl 3 − . -- Abstract: The oxidation behavior of chloride ions on platinum electrodes was investigated in a natural ionic liquid, 1-butyl-3-methyl-limidazolium tetrafluoroborate (BMIMBF 4 ) in the presence of high concentrations of 1-butyl-3-methyl-limidazolium chloride (BMIMCl). Analysis of the electrode reaction was explored using cyclic voltammetry, and chronoamperometry with a platinum micro-disk electrode, and bulk potentiostatic electrolysis and UV–vis spectroscopy. The anodic oxidation of chloride ions on the platinum micro-disk electrode in the mixture was considered to be an irreversible process with diffusion controlled as revealed by cyclic voltammetry. The diffusion coefficient, D, and the number of electrons transferred, n, for anodic oxidation of Cl − in BMIMBF 4 derived from results of chronoamperometry revealed that the oxidation of chloride ions was more likely to form tri-chloride ion, Cl 3 − but not chlorine, Cl 2 . Bulk electrolysis and UV–vis spectroscopy further confirmed that the tri-chloride ion was the main product from the overall oxidation of the chloride ion

  9. Butyl 2-(5-iodo-3-methylsulfinyl-1-benzofuran-2-ylacetate

    Uk Lee

    2009-02-01

    Full Text Available In the title compound, C15H17IO4S, the O atom and the methyl group of the methylsulfinyl substituent lie on opposite sides of the plane of the benzofuran fragment. The crystal structure is stabilized by weak intermolecular C—H...π interactions between a methyl H atom of the methylsulfinyl group and the benzene ring of the benzofuran system, and by an I...O halogen bond of 3.173 (3 Å and a nearly linear C—I...O angle of 171.7 (1°. In addition, the crystal structure exhibits weak intermolecular C—H...O hydrogen bonds. The O atom of the carbonyl group and the butyl chain are both disordered over two positions with site-occupancy factors from refinement of 0.55 (4 and 0.45 (4 (for the O atom, and 0.76 (2 and 0.24 (2 (for the butyl group.

  10. Enhancement of methyl tert-butyl ether degradation by the addition of readily metabolizable organic substrates

    Chen Dongzhi; Chen Jianmeng; Zhong Weihong

    2009-01-01

    Supplements with readily metabolizable organic substrates were investigated to increase the biomass and enhance degradation of methyl tert-butyl ether (MTBE) due to the low biomass yield of MTBE which has been one of the factors for low-rate MTBE degradation. The influence of various organic substrates on the rate of aerobic degradation of methyl tert-butyl ether (MTBE) by Methylibium petroleiphilum PM1 was investigated, and only yeast extract (YE), beef extract and tryptone exhibited stimulatory effect. With the concentration of each substrate being 100 mg/L, the average MTBE removal rate could increase to 1.29, 1.20 and 1.04 mg/(L h), respectively, in comparison with 0.71 mg/(L h) when carried out in medium without addition. The stimulatory effects of YE addition, as well as induction period required by MTBE degradation, varied dramatically with the storage conditions, pre-culture medium and concentrations of the inoculums. The extent of stimulatory effects of YE might be closely related to the proportion of induction period in the total time of MTBE-degradation. The removal efficiency increased from about 50% to 90.5% with the addition of YE in a packed-bed reactor loaded with calcium alginate immobilized cells.

  11. Mono- and di-n-butyl phosphates of some metals in spent nuclear fuel reprocessing

    Solovkin, A.S.

    1982-01-01

    Results of investigations which have been carried out in the Soviet Union for the last 10 years on the determination of the composition, structure, conditions of the formation and solubility of mono- and di-n-butyl phosphates of metals (U/sup 6 +/, Pu/sup 4 +/, Pu/sup 3 +/, Th, Zr, Fe/sup 3 +/, Am, Al, rare-earth elements), which are important for the processes of irradiated nuclear fuel reprocessing, are presented. A conclusion is made that zirconium mono- and di-n-butyl phosphates are the least soluble in aqueous and organic solvents of all investigated compounds. FeA/sub 3/ and AmA/sub 3/ are weakly soluble in aqueous solutions. The other compounds are sufficiently soluble in moderately acidic aqueous solutions or in DBP and TBP with dilutents. The obtained results indicate at the similarity of zirconium and plutonium (4) chemical properties; thorium, in this respect, is not an analogue of plutonium (4). Possible structural formulas of the investigated compounds are considered.

  12. Biodegradation of di-n-butyl phthalate by bacterial consortium LV-1 enriched from river sludge.

    Yangyang Wang

    Full Text Available A stable bacterial consortium (LV-1 capable of degrading di-n-butyl phthalate (DBP was enriched from river sludge. Community analysis revealed that the main families of LV-1 are Brucellaceae (62.78% and Sinobacteraceae (14.83%, and the main genera of LV-1 are Brucella spp. (62.78% and Sinobacter spp. (14.83%. The optimal pH and temperature for LV-1 to degrade DBP were pH 6.0 and 30°C, respectively. Inoculum size influenced the degradation ratio when the incubation time was < 24 h. The initial concentration of DBP also influenced the degradation rates of DBP by LV-1, and the degradation rates ranged from 69.0-775.0 mg/l/d in the first 24 h. Degradation of DBP was best fitted by first-order kinetics when the initial concentration was < 300 mg/l. In addition, Cd2+, Cr6+, and Zn2+ inhibited DBP degradation by LV-1 at all considered concentrations, but low concentrations of Pb2+, Cu2+, and Mn2+ enhanced DBP degradation. The main intermediates (mono-ethyl phthalate [MEP], mono-butyl phthalate [MBP], and phthalic acid [PA] were identified in the DBP degradation process, thus a new biochemical pathway of DBP degradation is proposed. Furthermore, LV-1 also degraded other phthalates with shorter ester chains (DMP, DEP, and PA.

  13. Combined Effects of Ultrasound and Immobilization Protocol on Butyl Acetate Synthesis Catalyzed by CALB

    Joana S. Alves

    2014-07-01

    Full Text Available It is well established that the performance of lipase B from Candida antarctica (CALB as catalyst for esterification reactions may be improved by the use of ultrasound technology or by its immobilization on styrene-divinylbenzene beads (MCI-CALB. The present research evaluated the synthesis of butyl acetate using MCI-CALB under ultrasonic energy, comparing the results against those obtained using the commercial preparation, Novozym 435. The optimal conditions were determined using response surface methodology (RSM evaluating the following parameters: reaction temperature, substrate molar ratio, amount of biocatalyst, and added water. The optimal conditions for butyl acetate synthesis catalyzed by MCI-CALB were: temperature, 48.8 °C; substrate molar ratio, 3.46:1 alcohol:acid; amount of biocatalyst, 7.5%; and added water 0.28%, both as substrate mass. Under these conditions, 90% of conversion was reached in 1.5 h. In terms of operational stability, MCI-CALB was reused in seven cycles while keeping 70% of its initial activity under ultrasonic energy. The support pore size and resistance are key points for the enzyme activity and stability under mechanical stirring. The use of ultrasound improved both activity and stability because of better homogeneity and reduced mechanical stress to the immobilized system.

  14. Biodegradation of Methyl tert-Butyl Ether by Co-Metabolism with a Pseudomonas sp. Strain

    Shanshan Li

    2016-09-01

    Full Text Available Co-metabolic bioremediation is supposed to be an impressive and promising approach in the elimination technology of methyl tert-butyl ether (MTBE, which was found to be a common pollutant worldwide in the ground or underground water in recent years. In this paper, bacterial strain DZ13 (which can co-metabolically degrade MTBE was isolated and named as Pseudomonas sp. DZ13 based on the result of 16S rRNA gene sequencing analysis. Strain DZ13 could grow on n-alkanes (C5-C8, accompanied with the co-metabolic degradation of MTBE. Diverse n-alkanes with different carbon number showed a significant influence on the degradation rate of MTBE and accumulation of tert-butyl alcohol (TBA. When Pseudomonas sp. DZ13 co-metabolically degraded MTBE with n-pentane as the growth substrate, a higher MTBE-degrading rate (Vmax = 38.1 nmol/min/mgprotein, Ks = 6.8 mmol/L and lower TBA-accumulation was observed. In the continuous degradation experiment, the removal efficiency of MTBE by Pseudomonas sp. Strain DZ13 did not show an obvious decrease after five times of continuous addition.

  15. Separation of Poly(styrene-block-t-butyl methacrylate) Copolymers by Various Liquid Chromatography Techniques

    Šmigovec Ljubič, Tina; Pahovnik, David; Žigon, Majda; Žagar, Ema

    2012-01-01

    The separation of a mixture of three poly(styrene-block-t-butyl methacrylate) copolymers (PS-b-PtBMA), consisting of polystyrene (PS) blocks of similar length and t-butyl methacrylate (PtBMA) blocks of different lengths, was performed using various chromatographic techniques, that is, a gradient liquid chromatography on reversed-phase (C18 and C8) and normal-phase columns, a liquid chromatography under critical conditions for polystyrene as well as a fully automated two-dimensional liquid chromatography that separates block copolymers by chemical composition in the first dimension and by molar mass in the second dimension. The results show that a partial separation of the mixture of PS-b-PtBMA copolymers can be achieved only by gradient liquid chromatography on reversed-phase columns. The coelution of the two block copolymers is ascribed to a much shorter PtBMA block length, compared to the PS block, as well as a small difference in the length of the PtBMA block in two of these copolymers, which was confirmed by SEC-MALS and NMR spectroscopy. PMID:22489207

  16. Densities and Kinematic Viscosities for the Systems Benzene + Methyl Formate, Benzene + Ethyl Formate, Benzene + Propyl Formate, and Benzene + Butyl Formate

    Emmerling, Uwe; Rasmussen, Peter

    1998-01-01

    a Redlich-Kister type of expression with temperature-independent parameters and the data for the systems benzene + ethyl formate, benzene + propyl formate, and benzene + butyl formate with temperature-dependent parameters. The viscosities have furthermore been compared to values predicted by means of the GC......Densities and kinematic viscosities have been measured for the system benzene + methyl formate at 20°C and for the systems benzene + ethyl formate, benzene + propyl formate, and benzene + butyl formate from 20°C to 50°C. The results for the system benzene + methyl formate have been correlated using...

  17. A Rare Case of Retrogastric Abscess Occurring Six Months after N-Butyl-2-Cyanoacrylate Injection into Gastric Varices

    Ikram Hussain

    2018-01-01

    Full Text Available Background. Injection with N-butyl-2-cyanoacrylate is a proven and successful therapeutic modality for treatment of patients with bleeding gastric varices. However, a variety of complications have also been associated with its use. Here, we report a rare case of retrogastric abscess which occurred almost six months after this therapy. This abscess was attributed to the hampered microbial clearance caused by the venous obliterations from N-butyl-2-cyanoacrylate. The abscess was successfully treated with 3 months of antibiotics.

  18. Isotope effects and the temperature dependences of the hyperfine coupling constants of muoniated sec-butyl radicals in condensed phases.

    Fleming, Donald G; Bridges, Michael D; Arseneau, Donald J; Chen, Ya Kun; Wang, Yan Alexander

    2011-04-07

    Reported here is the first μSR study of the muon (A(μ)) and proton (A(p)) β-hyperfine coupling constants (Hfcc) of muoniated sec-butyl radicals, formed by muonium (Mu) addition to 1-butene and to cis- and trans-2-butene. The data are compared with in vacuo spin-unrestricted MP2 and hybrid DFT/B3YLP calculations reported in the previous paper (I), which played an important part in the interpretation of the data. The T-dependences of both the (reduced) muon, A(μ)′(T), and proton, A(p)(T), Hfcc are surprisingly well explained by a simple model, in which the calculated Hfcc from paper I at energy minima of 0 and near ±120° are thermally averaged, assuming an energy dependence given by a basic 2-fold torsional potential. Fitted torsional barriers to A(μ)′(T) from this model are similar (~3 kJ/mol) for all muoniated butyl radicals, suggesting that these are dominated by ZPE effects arising from the C−Mu bond, but for A(p)(T) exhibit wide variations depending on environment. For the cis- and trans-2-butyl radicals formed from 2-butene, A(μ)′(T) exhibits clear discontinuities at bulk butene melting points, evidence for molecular interactions enhancing these muon Hfcc in the environment of the solid state, similar to that found in earlier reports for muoniated tert-butyl. In contrast, for Mu−sec-butyl formed from 1-butene, there is no such discontinuity. The muon hfcc for the trans-2-butyl radical are seemingly very well predicted by B3LYP calculations in the solid phase, but for sec-butyl from 1-butene, showing the absence of further interactions, much better agreement is found with the MP2 calculations across the whole temperature range. Examples of large proton Hfcc near 0 K are also reported, due to eclipsed C−H bonds, in like manner to C−Mu, which then also exhibit clear discontinuities in A(p)(T) at bulk melting points. The data suggest that the good agreement found between theory and experiment from the B3LYP calculations for eclipsed bonds in

  19. [Photometric determination of butyl "aeroflot" flotation agent (sodium dibutyl dithiophosphate) in the air of work zone and skin washings].

    Dorogova, V B; Kucheriavykh, E I; Sokolova, T V

    1989-01-01

    Photometric procedure of butyl "aeroflot" identification in the work zone air and in wash-out from workers' integument was developed, The procedure was based on the formation of yellow- and orange-dyed copper dibutyl dithiophosphate under butyl "aeroflot" interaction with copper sulphate with the subsequent photometry of dyed solutions for the wavelength of 420 nm in the 10-mm cell. Buffer solution with pH-9.2 was used as an absorbing solution for the workplace air sampling and integument wash-out.

  20. Moessbauer spectroscopic characterisation of catalysts obtained by interaction between tetra-n-butyl-tin and silica or silica supported rhodium

    Millet, J.M.M.; Toyir, J.; Didillon, B.; Candy, J.P.; Nedez, C.; Basset, J.M.

    1997-01-01

    Moessbauer spectroscopy at 78 K was used to study the interaction between tetra-n-butyl-tin and the surfaces of silica or silica supported rhodium. At room temperature, the tetra-n-butyl-tin was physically adsorbed on the surfaces. After reaction under hydrogen at 373 K, the formation of grafted organometallic fragments on the Rh surface was confirmed whereas with pure silica, ≡SiO-Sn(n-C 4 H 9 ) 3 moieties were observed. After treatment at 523 K, the rhodium grafted organometallic species was completely decomposed and there was formation of a defined bimetallic RhSn compound

  1. Simultaneous /sup 99m/Tc-p-butyl-IDA and 131I-rose bengal scintigraphy in neonatal jaundice

    Collier, B.D.; Treves, S.; Davis, M.A.; Heyman, S.; Subramanian, G.; McAfee, J.G.

    1980-01-01

    Eight neonates with jaundice were studied simultaneously with /sup 99m/Tc-p-butyl-IDA and 131 I-rose bengal. Due to physical decay, /sup 99m/Tc-p-butyl-IDA failed to demonstrate delayed excretion through the patent extrahepatic biliary tract in 3 of 5 patients with concomitant hepatitis; 131 I-rose bengal showed small-bowel activity in all 5. Neither agent demonstrated small-bowel activity in 3 neonates with extrahepatic biliary atresia. Based on this clinical trial, 131 I-rose bengal remains the radiopharmaceutical of choice for distinguishing between hepatitis and biliary atresia in these patients

  2. 40 CFR 721.10193 - 1-Butanaminium, N-(3-aminopropyl)-N-butyl-N-(2-carboxyethyl)-, N-coco acyl derivs., inner salts.

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false 1-Butanaminium, N-(3-aminopropyl)-N...-aminopropyl)-N-butyl-N-(2-carboxyethyl)-, N-coco acyl derivs., inner salts. (a) Chemical substance and...-aminopropyl)-N-butyl-N-(2-carboxyethyl)-, N-coco acyl derivs., inner salts (PMN P-06-263, Chemical B; CAS No...

  3. Synthesis of 2,6-diisopropyl-phenylcarbamoylmethyl-iminodiacetic acid (DISIDA) and 4-n-p-butyl-phenylcarbamoylmethyl-iminodiacetic acid (BUTYL-IDA). Preparation of lyophilized kit to be used as 99(supm)Tc agent in hepatobiliary system

    Hamada, E.S.; Barbosa, M.F. de; Theodora, M.A.; Almeida, M. de; Colturato, M.T.; Muramoto, E.; Silva, C.P.G. da.

    1987-08-01

    The synthesis of 2,6 diisopropyl IDA (DISIDA) and 4-n-butyl IDA (BUTIL-IDA) is described. Their spectroscopic properties, radiopharmaceutical preparation and their use as 99 (sup m)Tc complex agent in hepatobiliary studies, are also reported. (Author) [pt

  4. Butyl paraben and propyl paraben modulate bisphenol A and estradiol concentrations in female and male mice

    Pollock, Tyler; Weaver, Rachel E.; Ghasemi, Ramtin; Catanzaro, Denys de, E-mail: decatanz@mcmaster.ca

    2017-06-15

    People are routinely exposed to the antimicrobial preservatives butyl paraben (BP) and propyl paraben (PP), as well as the monomer of polycarbonate plastics, bisphenol A (BPA). These chemicals are reliably detected in human urine and potentially interact. We investigated whether BP or PP exposure can modulate the concentrations of {sup 14}C-BPA and 17β-estradiol (E{sub 2}). Female and male CF1 mice were each given a subcutaneous injection of oil containing 0 (vehicle), 1, 3, or 9 mg BP or PP, then given a dietary supplement containing 50 μg/kg {sup 14}C-BPA. Radioactivity was measured in tissues through liquid scintillation counting. Significantly elevated {sup 14}C-BPA concentrations were observed following BP treatment in blood serum of both sexes, as well as the lungs, uterus, and ovaries of females and the testes and epididymides of males. Treatment with PP significantly elevated {sup 14}C-BPA concentrations in the uterus only. In another experiment, female and male CF1 mice were each injected with vehicle, 3 mg BP, or 3 mg PP, and E{sub 2} was measured in urine 2–12 h later. Whereas PP did not affect E{sub 2}, BP significantly elevated E{sub 2} 6–10 h after injection in females and 8 h after injection in males. These data indicate that BP and PP can alter the pharmacokinetics of BPA in vivo, and that BP can modulate E{sub 2} concentrations. These results are consistent with evidence that parabens inhibit enzymes that are critical for BPA and E{sub 2} metabolism, and demonstrate the importance of considering concurrent exposure to multiple chemicals when determining regulatory exposure limits. - Highlights: • We studied whether paraben exposure affects the distribution of oral {sup 14}C-BPA. • Elevated {sup 14}C–BPA was observed in mice given butyl or propyl paraben. • We also studied whether paraben exposure affects natural E{sub 2} levels in urine. • Elevated E{sub 2} was observed in mice given butyl, but not propyl, paraben. • Parabens may

  5. PENGGUNAAN MERK NILON YANG BERBEDA PADA LALANGIT (Horizontal gillnet TERHADAP HASIL TANGKAPAN IKAN BETOK (Anabas testudineus (THE USE OF MARQUE NYLON DIFFERENT ON LALANGIT (Horizontal Gillnet AGAINST THE CATCH FISH BETOK (Anabas Testudineus

    Siti Aminah

    2017-02-01

    Full Text Available Tujuan dari Penelitian ini adalah untuk mengetahui (1 deskripsi lalat tangkap Lalangit yang biasa digunakan, (2 jumlah hasil tangkapan (catch yang diperoleh dari perbedaan beberapa merk nilon yang digunakan, (3 merk nilon yang terbaik sebagai bahan material lalangit (horizontal gillnet.  Metode penelitian yang digunakan adalah Rancangan Acak Kelompok (RAK dengan 6 perlakuan yaitu 6 jenis merk nilon yang berbeda.  Dari hasil penelitian   diperoleh jumlah hasil tangkapan yang paling banyak pada Lalangit yang menggunakan nilon merk damyl memperoleh jumlah hasil tangkapan sebanyak 50 ekor dengan berat total 1.728 gram,karena dari segi konstruksi atau bahan materialnya lembut yang menyebabkan hasil tangkapan tidak mudah meloloskan diri dari jaring karena ke elastisitasan dan warna biru dari nilon dapat menyerupai kondisi perairan sehingga ikan mudah tertipu keadaan daerah perairan tersebut dan didapatkan hasil tangkapan yang optimal. The purpose of this research is to know (1 the description of the commonly used lalangit, (2 the amount of the catch (catch are obtained from the difference in some brands of nylon that is used, (3 brands of nylon materials as the best lalangit (horizontal gillnet. The research method used was Random Design Group (RAK with 6 treatments IE 6 types of different brands of nylon. Of research results obtained the most number of catches a lot on Lalangit using the brand damyl earn 50 catches the tail with a total weight of 1.728 gram, because in terms of construction or its material soft materials that cause the catch is not easy to escape from nets due to elastisitasan and the blue color of nylon can resemble aquatic conditions so that the gullible fish State of the waters and the obtained results the optimal catch.

  6. INTERACTION OF METHYL-TERT BUTYL ETHER AND WATER STRESS ON SEED GERMINATION AND SEEDLING GROWTH IN SOIL MICROCOSMS

    Methyl tert-butyl ether (MTBE) is a widespread contaminant in surface and ground water in the United States. Frequently irrigation is used to water fields to germinate planted seeds and sustain plant growth. A likely possibility exists that water used may have some MTBE. Our s...

  7. Developmental and testicular toxicity of butyl benzyl phthalate in the rat and the impact of study design

    Piersma AH; Verhoef A; Dormans JAMA; Elvers LH; Valk V de; Biesebeek JD te; Pieters MN; Slob W; LEO

    1999-01-01

    The developmental toxicity of butyl benzyl phthalate was investigated in the rat in an alternative study design using ten treatment groups. The effect of exposure period was studied, and a comparison of reaction to treatment in pregnant versus non-pregnant females was made. The classical data

  8. Reactive Imprint Lithography: Combined Topographical Patterning and Chemical Surface Functionalization of Polystyrene-block-poly(tert-butyl acrylate) Films

    Duvigneau, Joost; Cornelissen, Stijn; Bardajı´Valls, Nuria; Schönherr, Holger; Vancso, Gyula J.

    2009-01-01

    Here, reactive imprint lithography (RIL) is introduced as a new, one-step lithographic tool for the fabrication of large-area topographically patterned, chemically activated polymer platforms. Films of polystyrene-block-poly(tert-butyl acrylate) (PS-b-PtBA) are imprinted with PDMS master stamps at

  9. Carbamoylcholine analogs as nicotinic acetylcholine receptor agonists--structural modifications of 3-(dimethylamino)butyl dimethylcarbamate (DMABC)

    Hansen, Camilla Petrycer; Jensen, Anders Asbjørn; Balle, Thomas

    2009-01-01

    Compounds based on the 3-(dimethylamino)butyl dimethylcarbamate (DMABC) scaffold were synthesized and pharmacologically characterized at the alpha(4)beta(2), alpha(3)beta(4,) alpha(4)beta(4) and alpha(7) neuronal nicotinic acetylcholine receptors (nAChRs). The carbamate functionality and a small...

  10. Voltammetric Determination of Nitro Derivative of Synthetic Antioxidant 2,6-di-tert-butyl-4-methyl-phenol

    Chýlková, J.; Machalický, O.; Tomášková, M.; Šelešovská, R.; Navrátil, Tomáš

    2016-01-01

    Roč. 49, č. 1 (2016), s. 92-106 ISSN 0003-2719 R&D Projects: GA ČR(CZ) GAP208/12/1645 Institutional support: RVO:61388955 Keywords : 2,6-di-tert-butyl-4-methyl-phenol * handing drop mercury electrode * nitration Subject RIV: CG - Electrochemistry Impact factor: 1.150, year: 2016

  11. Effect of lithium tetrafluoroborate on the solubility of carbon dioxide in the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate

    Durano Arno, S.; Lucas, S.; Shariati - Sarabi, A.; Peters, C.J.

    2012-01-01

    In this work, the phase behavior of the ternary system of carbon dioxide +1-butyl-3-methylimidazolium tetrafluoroborate + lithium tetrafluoroborate has been investigated. Mixtures of known concentrations of the salt, ionic liquid and carbon dioxide were prepared and their bubble point pressures were

  12. Ultrasonic promoted catalyst-free N-formylation of amines in neutral ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate

    Vinod T. Kamble

    2017-05-01

    Full Text Available A catalyst-free, simple and efficient protocol for N-formylation of alkyl, aryl, and heteroaryl amines with formic acid under ultrasonic irradiation at room temperature using 1-butyl-3-methylimidazolium tetrafluoroborate [Bmim]BF4 as a neutral medium is described.

  13. When does the fluazifop-P-butyl degradate, TFMP, leach through an agricultural loamy soil to groundwater?

    Vendelboe, Anders Lindblad; Norgaard, Trine; Olsen, Preben

    2016-01-01

    In intensely cultivated regions, it is crucial to have knowledge of the leaching potential related to pesticides in agricultural production. This is especially true in countries, like Denmark, that base its drinking water supply on untreated groundwater. Since fluazifop-P-butyl (FPB) is applied...

  14. UV absorption spectra, kinetics and mechanism for alkyl and alkyl peroxy radicals originating from t-butyl alcohol

    Langer, S.; Ljungström, E.; Sehested, J.

    1994-01-01

    Alkyl and alkyl peroxy radicals from 1-butyl alcohol (TBA), HOC (CH3)2CH2. and HOC(CH3)2CH2O2. have been studied in the ps phase at 298 K. Two techniques were used: pulse radiolysis UV absorption to measure the spectra and kinetics, and long path-length Fourier transform infrared spectroscopy (FTIR...

  15. DEVELOPMENT OF PHYSIOLOGICAL-BASED PHARMACOKINETIC MODEL FOR DERMAL ABSORPTION NAD PENETRATION OF METHYL TERTIARY BUTYL ETHER IN HUMANS

    Background: Methyl tertiary butyl ether (MTBE) is a volatile organic chemical that is added to gasoline as an octane booster and to reduce vehicular emissions of carbon monoxide. MTBE is introduced into the environment through fuel spills, leakage of storage tanks, and evaporat...

  16. In situ NMR and modeling studies of nitroxide mediated copolymerization of styrene and n-butyl acrylate

    Hlalele, L.; Klumperman, L.

    2011-01-01

    The combination of in situ1H NMR and in situ31P NMR was used to study the nitroxide mediated copolymerization of styrene and n-butyl acrylate. The alkoxyamine MAMA-DEPN was employed to initiate and mediate the copolymerization. The nature of the ultimate/terminal monomer units of dormant polymer

  17. Substituted 2,2'-bipyridines by nickel-catalysis: 4,4'-di-tert-butyl-2,2'-bipyridine.

    Buonomo, Joseph A; Everson, Daniel A; Weix, Daniel J

    2013-11-01

    A simple, ligand-free synthesis of the important bipyridyl ligand 4,4'-di- tert -butyl-2,2'-bipyridine is presented. 5,5'-bis(trifluoromethyl)-2,2'-bipyridine is also synthesized by the same protocol. The syntheses efficiently couple the parent 2-chlorpyridies by a nickel-catalyzed dimerization with manganese powder as the terminal reductant.

  18. The beneficial effects of mixing spiro-OMeTAD with n-butyl-substituted copper phthalocyanine for perovskite solar cells

    Nouri, Esmaiel; Wang, Yu-Long; Chen, Qian; Xu, Jia-Ju; Dracopoulos, Vassilios; Sygellou, Lamprini; Xu, Zong-Xiang; Mohammadi, Mohammad Reza; Lianos, Panagiotis

    2016-01-01

    Highlights: • Soluble n-butyl substituted copper phthalocyanine. • Mixture with spiro-OMeTAD and employment in perovskite solar cells. • Impressive improvement of perovskite solar cell efficiency. • n-Butyl derivative gives better results than tert-butyl derivative - Abstract: Perovskite solar cells have been constructed under ambient conditions by using 2,2',7,7'-Tetrakis-(N,N-di-4-methoxyphenylamino)-9,9'-spirobifluorene (spiro-OMeTAD) mixed with a small quantity of soluble tetra-n-butyl substituted copper phthalocyanine as hole transporting material. The introduction of the phthalocyanine derivative resulted in an impressive increase of cell efficiency, which changed from 10.4% in the absence to 15.4% in the presence of phthalocyanine. This effect is related to the creation of deep traps in the hole transporting phase which block back-travelling electrons as well as to the improvement of the structural quality of the spiro-OMeTAD film in the presence of phthalocyanine. Both functionalities decrease shunt paths within the hole transporting phase resulting in increasing the fill factor and the open-circuit voltage of the cell.

  19. SYNTHESIS OF METHYL TERT-BUTYL ETHER CATALYZED BY ACIDIC ION-EXCHANGE RESINS - INFLUENCE OF THE PROTON ACTIVITY

    PANNEMAN, HJ; BEENACKERS, AACM

    1995-01-01

    The catalytic activity of various strong acid ion-exchange resins on the synthesis of methyl tert-butyl ether (MtBE) from methanol and isobutene has been investigated. Relative to Amberlyst 15, Kastel CS 381 and Amberlyst CSP have similar rate constants, whereas Duolite ES 276 and Amberlyst XE 307

  20. Di-iso-Butyl Phthalate MATERNAL AND FETAL DATA FROM THE LE GRAY RESEARCH TEAM FOR NCEA June 15 2016

    this file contains the raw data on the effects of in utero administration of di-iso-butyl phthalate on maternal weight gain during dosing and the numbers of fetuses and fetal resorptions. The data have all been previously published, as described on the file metadata sheet.

  1. Novel process window for the safe and continuous synthesis of tert.-butyl peroxy pivalate in a micro reactor

    Illg, T.; Hessel, V.; Löb, P.; Schouten, J.C.

    2011-01-01

    In this paper, the two step synthesis of tert.-butyl peroxy pivalate using two different flow regimes is introduced, in particular the use of "segmented flow" and the concept of "dispersed flow". The use of the segmented flow process, in this case, is challenging due to the very low interfacial

  2. Crystal structure of 2-tert-butyl-1,3-thiazolo[4,5-b]pyridine

    Gamal A. El-Hiti

    2014-09-01

    Full Text Available The title compound, C10H12N2S, does not contain any strong hydrogen-bond donors but two long C—H...N contacts are observed in the crystal structure, with the most linear interaction linking molecules along [010]. The ellipsoids of the tert-butyl group indicate large librational motion.

  3. Quercetin protects human hepatoma HepG2 against oxidative stress induced by tert-butyl hydroperoxide

    Alia, Mario; Ramos, Sonia; Mateos, Raquel; Granado-Serrano, Ana Belen; Bravo, Laura; Goya, Luis

    2006-01-01

    Flavonols such as quercetin, have been reported to exhibit a wide range of biological activities related to their antioxidant capacity. The objective of the present study was to investigate the protective effect of quercetin on cell viability and redox status of cultured HepG2 cells submitted to oxidative stress induced by tert-butyl hydroperoxide. Concentrations of reduced glutathione and malondialdehyde, generation of reactive oxygen species and activity and gene expression of antioxidant enzymes were used as markers of cellular oxidative status. Pretreatment of HepG2 with 10 μM quercetin completely prevented lactate dehydrogenase leakage from the cells. Pretreatment for 2 or 20 h with all doses of quercetin (0.1-10 μM) prevented the decrease of reduced glutathione and the increase of malondialdehyde evoked by tert-butyl hydroperoxide in HepG2 cells. Reactive oxygen species generation induced by tert-butyl hydroperoxide was significantly reduced when cells were pretreated for 2 or 20 h with 10 μM and for 20 h with 5 μM quercetin. Finally, some of the quercetin treatments prevented the significant increase of glutathione peroxidase, superoxide dismutase, glutathione reductase and catalase activities induced by tert-butyl hydroperoxide. Gene expression of antioxidant enzymes was also affected by the treatment with the polyphenol. The results of the biomarkers analyzed clearly show that treatment of HepG2 cells in culture with the natural dietary antioxidant quercetin strongly protects the cells against an oxidative insult

  4. Effect of Polyhedral Oligomeric Silsesquioxane (POSS) Substituents on the Rheological Behavior in Butyl Methacrylate/POSS Copolymers

    2008-10-27

    was repeated twice, dissolving the product in chloroform and diethyl ether, respectively. The polymer was dried at 60 °C under vacuum overnight...the Tg of the i Bu remains the same. Table 1. Tg for Butyl Methacrylate-co- Propyl Methacryl POSS Polymers with Various POSS Substituents

  5. Effect of Mesoporous Diatomite Particles on the Kinetics of SR&NI ATRP of Styrene and Butyl Acrylate

    Khezri, Khezrollah; Ghasemi, Moosa; Fazli, Yousef

    2018-05-01

    Mesoporous diatomite particles were employed to prepare different poly(styrene-co-butyl acrylate)/diatomite nanocomposites. Diatomite nanoplatelets were used for in situ copolymerization of styrene and butyl acrylate by SR&NI ATRP to synthesize well-defined poly(styrene-co-butyl acrylate) nanocomposites. Nitrogen adsorption/desorption isotherm is applied to examine surface area and structural characteristics of the diatomite nanoplatelets. Evaluation of pore size distribution and morphological studies were also performed by SEM and TEM. Conversion and molecular weight determinations were carried out using gas and size exclusion chromatography respectively. Addition of 3 wt% pristine mesoporous diatomite nanoplatelets leads to increase of conversion from 73 to 89%. Molecular weight of poly(styrene-co-butyl acrylate) chains increases from 17,115 to 20,343 g·mol-1 by addition of 3 wt% pristine mesoporous diatomite; however, polydispersity index values increases from 1.14 to 1.37. Increasing thermal stability of the nanocomposites is demonstrated by TGA. Differential scanning calorimetry shows an increase in glass transition temperature from 35.26 to 39.61°C by adding 3 wt% of mesoporous diatomite nanoplatelets.

  6. Dissolution of uranium dioxide in supercritical carbon dioxide modified with tri-n-butyl phosphate-hydrogen peroxide

    Kanekar, A.S.; Pathak, P.N.; Mohapatra, P.K.; Manchanda, V.K.

    2009-01-01

    Direct dissolution of uranium dioxide in supercritical carbon dioxide modified with tri-n-butyl phosphate (TBP) has been attempted. The effects of TBP concentration and pressure on the extraction of uranium have been studied. Addition of hydrogen peroxide in the modifier enhances the dissolution/extraction of uranium. (author)

  7. Rheo-optical two-dimensional (2D) near-infrared (NIR) correlation spectroscopy for probing strain-induced molecular chain deformation of annealed and quenched Nylon 6 films

    Shinzawa, Hideyuki; Mizukado, Junji

    2018-04-01

    A rheo-optical characterization technique based on the combination of a near-infrared (NIR) spectrometer and a tensile testing machine is presented here. In the rheo-optical NIR spectroscopy, tensile deformations are applied to polymers to induce displacement of ordered or disordered molecular chains. The molecular-level variation of the sample occurring on short time scales is readily captured as a form of strain-dependent NIR spectra by taking an advantage of an acousto-optic tunable filter (AOTF) equipped with the NIR spectrometer. In addition, the utilization of NIR with much less intense absorption makes it possible to measure transmittance spectra of relatively thick samples which are often required for conventional tensile testing. An illustrative example of the rheo-optical technique is given with annealed and quenched Nylon 6 samples to show how this technique can be utilized to derive more penetrating insight even from the seemingly simple polymers. The analysis of the sets of strain-dependent NIR spectra suggests the presence of polymer structures undergoing different variations during the tensile elongation. For instance, the tensile deformation of the semi-crystalline Nylon 6 involves a separate step of elongation of the rubbery amorphous chains and subsequent disintegration of the rigid crystalline structure. Excess amount of crystalline phase in Nylon 6, however, results in the retardation of the elastic deformation mainly achieved by the amorphous structure, which eventually leads to the simultaneous orientation of both amorphous and crystalline structures.

  8. Wet-Oxidation of Spent Organic Waste Tri-butyl Phosphate/Diluents

    El-Dessouky, M.I.; Abed El-Aziz, M.M.; El-Mossalamy, E.H.; Aly, H.F.

    1999-01-01

    Tri-Butyl Phosphate was used in reprocessing of spent nuclear fuel in the purex process. The amount of uranium retained in the organic phase depends on the type of TBP/Diluent. Destruction of spent TBP is of high interest in waste management. In the present work, oxidative degradation of TBP diluted with kerosene, carbon tetrachloride, benzene and toluene using potassium permanganate as oxidant was carried out to produce stable inorganic dry particle residue which is then immobilized in different matrices. The different factors affecting the destruction of spent waste was investigated. The up take and decontamination factor for both 152 and 154 Eu and 181 Hf and the analysis of the final product have been studied

  9. Radiation-Induced Polymerization of Butyl Acrylate for Recovery of Organic Solvents

    Kattan, M.; Al-Kassiri, H.

    2011-01-01

    Radiation-induced polymerization of butyl acrylate using 60 Co gamma rays has been investigated under different conditions, such as irradiation dose (0-130 kGy), dose rate (10 kGy/h), and temperature (25-70 degree C). A linear relationship between conversion and temperature of irradiation was found. The activation energy (E) of 9.37 kJ/mol was obtained from kinetic analysis of the result from the polymerization at 10 kGy/h. Thermal properties were examined using differential scanning calorimetry and thermal gravimetric analysis. Efficient extraction of organic solvents including chloroform, chlorobenzene, carbon tetrachloride, benzene, styrene was revealed by the swelling and releasing measurements. These results indicate the feasibility of applying this polymer, which was prepared by radiation-induced polymerization, to management of organic wastes in the field of environment. (author)

  10. Radiation-Induced Polymerization of Butyl Acrylate for Recovery of Organic Solvents

    Kattan, M.; Al-kassiri, H.

    2010-01-01

    Radiation-induced polymerization of butyl acrylate (BAc) using 60 Co gamma rays has been investigated under different conditions such as irradiation dose (0-130 kGy), dose rate (10 kGy/h) and temperature (25-70 C). A linear relationship between conversion and temperature of irradiation was found. The activation energy (E) of 9.37 kJ/mol was obtained from kinetic analysis of the result from the polymerization at 10 kGy/h. Thermal properties. were examined using differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Efficient extraction of organic solvents including chloroform, chlorobenzene, carbon tetrachloride, benzene, styrene was revealed by the swelling and releasing measurements. These results indicate the feasibility of applying this polymer, which was prepared by radiation-induced polymerization, to management of organic wastes in the field of environment. (author)

  11. Inhibition Effect of 1-Butyl-4-Methylpyridinium Tetrafluoroborate on the Corrosion of Copper in Phosphate Solutions

    M. Scendo

    2011-01-01

    Full Text Available The influence of the concentration of 1-Butyl-4-methylpyridinium tetrafluoroborate (4MBPBF4 as ionic liquid (IL on the corrosion of copper in 0.5 M PO43− solutions of pH 2 and 4 was studied. The research involved electrochemical polarization method, and scanning electron microscopy (SEM technique. The results obtained showed that the inhibition efficiency of corrosion of copper increases with an increase in the concentration of 4MBPBF4 but decreases with increasing temperature. The thermodynamic functions of corrosion analysis and adsorptive behavior of 4MBPBF4 were carried out. During the test, the adsorption of the inhibitor on the copper surface in the phosphate solutions was found to obey the Langmuir adsorption isotherm and had a physical mechanism.

  12. Radiation graft copolymerization of n-butyl acrylate on natural rubber latex

    Sundardi, F.; Kadariah, S.

    1986-01-01

    A method of radiation graft copolymerization of n-butyl acrylate (NBA) on natural rubber (NR) latex has been studied. The rate of conversion increases with the increase of NBA in latex. An irradiation dose of about 12 kGy is needed to obtain 90% conversion with 40 phr of NBA in latex. Tensile strength, tear strength, and elongation at break of grafted NR are found to decrease with increasing degree of grafting. The physical strength of a vulcanizate prepared from a mixture of NR and ply-NBA was found to be better than that of NBA-NR graft copolymer vulcanizate. The graft copolymerization reaction takes place in the outer layer of NR particles, and because the secondary bonds between poly-NBA molecules may be weaker than those between NR molecules, the existence of a poly-NBA layer in NR particles will decrease its physical strength

  13. Design and Control of Glycerol-tert-Butyl Alcohol Etherification Process

    Elena Vlad

    2012-01-01

    Full Text Available Design, economics, and plantwide control of a glycerol-tert-butyl alcohol (TBA etherification plant are presented. The reaction takes place in liquid phase, in a plug flow reactor, using Amberlyst 15 as a catalyst. The products' separation is achieved by two distillation columns where high-purity ethers are obtained and a section involving extractive distillation with 1,4-butanediol as solvent, which separates TBA from the TBA/water azeotrope. Details of design performed in AspenPlus and an economic evaluation of the process are given. Three plantwide control structures are examined using a mass balance model of the plant. The preferred control structure fixes the fresh glycerol flow rate and the ratio glycerol + monoether : TBA at reactor-inlet. The stability and robustness in the operation are checked by rigorous dynamic simulation in AspenDynamics.

  14. Photoelectric conversion and electrochromic properties of lutetium tetrakis(tert-butyl)bisphthalocyaninate

    Hu, Andrew Teh; Hu Tenyi; Liu Lungchang

    2003-01-01

    Both photoelectric and electrochromic effects on lutetium tetrakis(tert-butyl)bisphthalocyaninate (Lu(TBPc) 2 ) have been carried out in this study. Lu(TBPc) 2 is known for its electrochromic performance, but its photoelectric effect has not mentioned in the literature. The electrochromic properties of Lu(TBPc) 2 have been measured by cyclic voltammetry (CV) and UV-Vis spectrometer at the same time. It takes less than 1.5 s for the color to change from red to green under 0.9 V. Its cycle life is at least over 500 times. Furthermore, we also investigate its photoelectric conversion properties. Its photoelectric cell exhibits a positive photo-electricity conversion effect with a short-circuit photocurrent (46.4 μA/cm 2 ) under illumination of white light (1.201 mW/cm 2 )

  15. Structure and Supersaturation of Highly Concentrated Solutions of Buckyball in 1-Butyl-3-Methylimidazolium Tetrafluoroborate

    Fileti, E. E.; Chaban, V. V.

    2014-01-01

    Solubilization of fullerenes is of high interest because of their wide usage in both fundamental research and numerous applications. This paper reports molecular dynamics (MD) simulations of saturated and supersaturated solutions of C-60 in 1-butyl-3-methylimidazolium tetrafluoroborate, [C4C1IM......-long real-time dynamics. The ion-molecular structure patterns in saturated and supersaturated solutions are distinguished in terms of radial distribution functions and cluster analysis of the solute particles. The cation separated solute pair is found to be a common structure in both saturated......][BF4], room-temperature ionic liquid (RTIL). The simulations cover a wide range of temperatures between 280 and 500 K at ambient pressure. Unlike in simpler solvents, C-60 in [C4C1IM][BF4] forms highly supersaturated solutions, whose internal arrangement remains unaltered during nearly a microsecond...

  16. Study of n-Butyl Acrylate Self-Initiation Reaction Experimentally and via Macroscopic Mechanistic Modeling

    Ahmad Arabi Shamsabadi

    2016-04-01

    Full Text Available This paper presents an experimental study of the self-initiation reaction of n-butyl acrylate (n-BA in free-radical polymerization. For the first time, the frequency factor and activation energy of the monomer self-initiation reaction are estimated from measurements of n-BA conversion in free-radical homo-polymerization initiated only by the monomer. The estimation was carried out using a macroscopic mechanistic mathematical model of the reactor. In addition to already-known reactions that contribute to the polymerization, the model considers a n-BA self-initiation reaction mechanism that is based on our previous electronic-level first-principles theoretical study of the self-initiation reaction. Reaction rate equations are derived using the method of moments. The reaction-rate parameter estimates obtained from conversion measurements agree well with estimates obtained via our purely-theoretical quantum chemical calculations.

  17. Electrochemistry of TiF4 in 1-butyl-2,3-dimethylimidazolium tetrafluoroborate

    Andriyko, Yuriy; Andriiko, Alexander; Babushkina, Olga B.; Nauer, Gerhard E.

    2010-01-01

    Electrochemical behaviour of Ti(IV) species in the ionic liquid (IL) 1-butyl-2,3-dimethylimidazolium tetrafluoroborate (BMMImBF 4 ) was studied by means of chronopotentiometry (CP) and cyclic voltammetry (CV) in melts with different concentrations of TiF 4 (2-35 mol%) within a temperature range of 65-180 deg. C. The electrochemical reduction of Ti(IV) was suggested to proceed via the sequence of one-electron steps with the formation of poorly soluble low valence intermediates (LVI). LVIs undergo further solid-state electrochemical reduction to Ti metal. Thin Ti coatings on a Pt substrate were thus obtained and characterized by ESEM method. FTIR spectroscopy was used for identification of the electrochemical active species of Ti(IV). The reaction 2BF 4 - + TiF 4 ↔ TiF 6 2- + 2BF 3 ↑ takes place in the concentrated solutions of TiF 4 at elevated temperatures.

  18. [n-Butyl Alcohol-soluble Chemical Constituents of Psidium guajava Leaves].

    Chen, Gang; Wan, Kai-hua; Fu, Hui-zheng; Yan, Qing-wei

    2015-03-01

    To study the chemical constituents of the leaves of Psidium guajava. The chemical constituents were isolated by column chromatography on silica gel, Sephadex LH-20 and MPLC. Their chemical structures were elucidated on the basis of special analysis. Seven compounds were isolated from n-butyl alcohol fraction, whose structures were elucidated as morin-3-O-α-L-arabopyranoside (1), morin-3-O-α-L-iyxopyranoside (2), 2,6-dihydroxy-4-O-β-D-glucopyranosyl-benzophenone (3), casuarictin (4),2,6-dihydroxy-3,5-dimethyl-4-O-(6"-O-galloyl-β-D-glucopyranosyl)-benzophenone(5), globulusin A(6), and kaempferol-3-O-β-D-(6"-galloyl) galactopyranoside (7). Compounds 3 and 5 ~ 7 are isolated from this plant for the first time.

  19. Electron density analysis of 1-butyl-3-methylimidazolium chloride ionic liquid.

    del Olmo, Lourdes; Morera-Boado, Cercis; López, Rafael; García de la Vega, José M

    2014-06-01

    An analysis of the electron density of different conformers of the 1-butyl-3-methylimidazolium chloride (bmimCl) ionic liquid by using DFT through the BVP86 density functional has been obtained within the framework of Bader's atom in molecules (AIM), localized orbital locator (LOL), natural bond orbital (NBO), and deformed atoms in molecules (DAM). We also present an analysis of the reduced density gradients that deliver the non-covalent interaction regions and allow to understand the nature of intermolecular interactions. The most polar conformer can be characterized as ionic by AIM, LOL, and DAM methods while the most stable and the least polar shows shared-type interactions. The NBO method allows to comprehend what causes the stabilization of the most stable conformer based on analysis of the second-order perturbative energy and the charge transferred among the natural orbitals involved in the interaction.

  20. Radiation polymerization of butyl acrylate for using as organic compounds recovery system from waste water

    Kattan, M.; Al-Kassiri, H.

    2008-02-01

    In this work, radiation polymerization of butyl acrylate using 60 Co gamma rays was studied. The effects of different parameters, such as the irradiation dose, dose rate and the temperature of irradiation on the polymerization were investigated. The relationship between polymerization yield with the dose rate and the temperature found to be linear. The kinetic of irradiation polymerization at 10 kGy/h was studied. The activation energy of reaction was calculated and it was E=9.27 j/mol. The thermal properties and the effect of irradiation dose on the glass transition were investigated. The application of this polymer in the field of environment treatment such as extraction of organics compounds dissolved in water was studied. The swelling in several organic compounds was studied, the weight percentages of both the swelling and the liberation were calculated. (author)