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Sample records for radiation curable coatings

  1. High performance radiation curable hybrid coatings

    Science.gov (United States)

    Nik Salleh, Nik Ghazali; Sofian Alias, Mohd; Gläsel, H.-J.; Mehnert, R.

    2013-03-01

    Radiation curing is one of the most effective processes to produce rapidly composite materials at ambient temperature. Silica nanoparticles can be introduced into radiation curable resins to produce scratch and abrasion resistant materials, which can be used as sealants or clear coatings. In preparation of radiation cured polymeric composites for wood based products such as medium density fiberboard etc., we synthesized radiation curable silico-organic nanoparticles from silica/acrylates system. These nano-sized silica particles were used as fillers. Epoxy acrylates was used as prepolymer while pentaerythritol triacrylate and tetraacrylate (PETIA) was used as monomer. The acrylated epoxy resin synthesized from palm oil based product (EPOLA) i.e. bio-renewable raw materials was also used in the system. The surface of the silica was chemically modified to improve the embedding of the filler within the acrylate matrix. Modification of the silica surface using silane was done to overcome the problem of incompatibility with acrylates at high silica contents. The nature of the nanoparticles is now changed from hydrophilic to organophilic. In these investigations, we use low energy electron beam accelerator to initiate polymerization and interaction at the interface between the nanoparticles and the monomeric materials. These polymerization active nanoparticles were obtained by heterogeneous hydrolytic condensation of the silane to the silanol groups of the silica particles. Formulations useful for technical coating processes could be prepared and these composite materials showed highly improved mechanical properties. They also provided a high network density whilst the coatings remain transparent. These polymeric nanocomposites show excellent resistances toward abrasion properties including scratch property as compared to pure acrylates.

  2. BARRIERS TO THE USE OF RADIATION-CURABLE ADHESIVES IN THE COATED AND LAMINATED SUBSTRATE MANUFACTURING INDUSTRY

    Science.gov (United States)

    The paper gives results of an investigation of barriers to the use of radiation-cured technology in the coated and laminated substrate manufacturing industry. t presents information gathered from radiation-curable coating and equipment suppliers as well as technical publications....

  3. UV curable hard coatings on polyesters

    Science.gov (United States)

    Datashvili, Tea; Brostow, Witold; Kao, David

    2006-10-01

    UV curable, hard and transparent hybrid inorganic-organic coatings with covalent links between the inorganic and the organic networks were prepared using organically crosslinked heteropolysiloxanes based on the sol-gel process. The materials were applied onto polyester sheets and UV cured. The deposition was followed by a thermal treatment to improve mechanical properties of the coatings. High light transmission and the resulting thermophysical properties indicate the presence of a nanoscale hybrid composition. The coatings show excellent adhesion to polyesters even without using primers. Further mechanical characterization shows that the coatings provide high hardness and good abrasion resistance.

  4. Ultraviolet-radiation-curable paints

    Energy Technology Data Exchange (ETDEWEB)

    Grosset, A M; Su, W F.A.; Vanderglas, E

    1981-09-30

    In product finishing lines, ultraviolet radiation curing of paints on prefabricated structures could be more energy efficient than curing by natural gas fired ovens, and could eliminate solvent emission. Diffuse ultraviolet light can cure paints on three dimensional metal parts. In the uv curing process, the spectral output of radiation sources must complement the absorption spectra of pigments and photoactive agents. Photosensitive compounds, such as thioxanthones, can photoinitiate unsaturated resins, such as acrylated polyurethanes, by a free radical mechanism. Newly developed cationic photoinitiators, such as sulfonium or iodonium salts (the so-called onium salts) of complex metal halide anions, can be used in polymerization of epoxy paints by ultraviolet light radiation. One-coat enamels, topcoats, and primers have been developed which can be photoinitiated to produce hard, adherent films. This process has been tested in a laboratory scale unit by spray coating these materials on three-dimensional objects and passing them through a tunnel containing uv lamps.

  5. Hyperbranched Polyurethane Acrylate Applied to UV Curable Flame Retardant Coatings

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ UV curable hyperbranched prepolymers based on amine-ester, ester-amide and ether-amide started with AB2-type monomers have been prepared by the authors[1~3]. A se-ries of work on allyl ether maleate hyperbranched polyesters for UV curing coatings by Hult and his colleagues has been reported[4]. However, the UV cured films from those materials are all flammable when attached to fire without addition of flame retardants.

  6. A Photosensitive Copolymer for UV-curable Eleetrodeposition Coatings

    Institute of Scientific and Technical Information of China (English)

    LIU Ren; LI Xiaojie; AN Fenglci; ZHANG Shengwen; LIU Xiaoya

    2011-01-01

    A series of photosensitive random copolymers (UPDHES) were prepared by introducing acrylate groups onto the side chain of the copolymer backbone of N,N-domethyl amimethyl methacrylate (DMAEMA),2-hydroxypropyl acrylate (HEA),2-ethylhexyl acrylate (EHA),and styrene (St) (PDHES).The molecular structure of UPDHES was characterized by FTIR,1HNMR and GPC.The photopolymerization kinetics of UPDHES with different C=C content was investigated using real time FTIR in which it was found that the UPDHES system had notable photosensitivity.The effect of C=C content on the properties of cured films were studied by evaluating various film properties such as thermal stability,glass transition temperature and tensile properties.The thermal degradation of cured films was investigated via thermogravimetric analysis/infrared spectrometry (TGA-IR).Thus a series of UV-curable electrodeposition coatings with good photosensitivity and mechanical properties were prepared from a low-cost photosensitive random copolymer.

  7. Enhanced propellant performance via environmentally friendly curable surface coating

    Directory of Open Access Journals (Sweden)

    Thelma Manning

    2017-06-01

    Full Text Available Surface coating of granular propellants is widely used in a multiplicity of propellants for small, medium and large caliber ammunition. All small caliber ball propellants exhibit burning progressivity due to application of effective deterrent coatings. Large perforated propellant grains have also begun utilizing plasticizing and impregnated deterrent coatings with the purpose of increasing charge weights for greater energy and velocity for the projectile. The deterrent coating and impregnation process utilizes volatile organic compounds (VOCs and hazardous air pollutants (HAPs which results in propellants that need to be forced air dried which impacts air quality. Propellants undergo temperature fluctuations during their life. Diffusion coefficients vary exponentially with variations in temperature. A small temperature increase can induce a faster migration, even over a short period of time, which can lead to large deviations in the concentration. This large concentration change in the ammunition becomes a safety or performance liability. The presence of both polymeric deterrents and nitroglycerin(NG in the nitrocellulose matrix and organic solvents leads to higher diffusion rates. This results in continued emissions of VOCs and HAPs. Conventional polymers tend to partition within the propellant matrix. In other words, localized mixing can occur between the polymer and underlying propellant. This is due to solvent induced softening of the polymer vehicle over the propellant grain. In effect this creates a path where migration can occur. Since nitrate esters, like NG, are relatively small, it can exude to the surface and create a highly unstable and dangerous situation for the warfighter. Curable polymers do not suffer from this partitioning due to “melting” because no VOC solvents are present. They remain surface coated. The small scale characterization testing, such as closed bomb testing, small scale sensitivity, thermal stability, and

  8. Water-soluble UV curable urethane methyl acrylate coating:preparation and properties

    Institute of Scientific and Technical Information of China (English)

    魏燕彦; 罗英武; 李宝芳; 李伯耿

    2004-01-01

    Two kinds of water-soluble and ultraviolet (UV) curable oligomers were synthesized and characterized. The oligomers were evaluated as resins for water-based UV curable coating. The rheology of the two oligomers' aqueous solutions was investigated in terms of solid fraction, pH dependence, and temperature dependence. The solutions were found to be Newtonian fluid showing rather low viscosity even at high solid fraction of 0.55. The drying process of the coatings and the properties of the cured coatings were studied by comparing them with water-dispersed UV-curable polyurethane methyl acrylate. It was evident that the water-soluble coating dried more slowly; and that the overall properties were inferior to those of the water-dispersed coating.

  9. UV-curable nanocasting technique to prepare bioinspired superhydrophobic organic-inorganic composite anticorrosion coatings

    Directory of Open Access Journals (Sweden)

    K. C. Chang

    2015-02-01

    Full Text Available A UV-curing technique was used to develop advanced anticorrosive coatings made of a poly(methyl methacrylate (PMMA/silica composite (PSC with bioinspired Xanthosoma sagittifolium leaf-like superhydrophobic surfaces. First of all, a transparent soft template with negative patterns of xanthosoma sagittifolium leaf can be fabricated by thermally curing the polydimethylsiloxane (PDMS pre-polymer in molds at 60°C for 4 h, followed by detaching PDMS template from the surface of natural leaf. PSC coatings with biomimetic structures can be prepared by performing the UV-radiation process upon casting UV-curable precursor with photo-initiator onto cold-rolled steel (CRS electrode under PDMS template. Subsequently, UV-radiation process was carried out by using light source with light intensity of 100 mW/cm2 with exposing wavelength of 365 nm. Surface morphologies of the as-synthesized hydrophobic PMMA (HP and superhydrophobic PSC (SPSC coatings showed a large number of micro-scaled mastoids, each decorated with many nano-scaled wrinkles that were systematically investigated by using scanning electron microscopy (SEM. The contact angles of water droplets on the sample surfaces can be increased from ~81 and 103° on PMMA and PSC surfaces to ~148 and 163° on HP and SPSC surfaces, respectively. The SPSC coating was found to provide an advanced corrosion protection effect on CRS electrodes compared to that of neat PMMA, PSC, and HP coatings based on a series of electrochemical corrosion measurements in 3.5 wt% NaCl electrolyte. Enhanced corrosion protection of SPSC coatings on CRS electrodes can be illustrated by that the silica nanoparticles on the small papillary hills of the bioinspired structure of the surface further increased the surface roughness, making the surface exhibit superior superhydrophobic, and thus leading to much better anticorrosion performance.

  10. Novel, UV-curable coatings containing a tethered biocide: Synthesis, characterization, and antimicrobial activity.

    Science.gov (United States)

    Chen, Zhigang; Chisholm, Bret J; Stafslien, Shane; He, Jie; Patel, Sandeep

    2010-11-01

    Cationic, UV -curable coatings containing the tethered biocide, triclosan, were produced and their antimicrobial activity toward Staphylococcus epidermidis and Escherichia coli determined. Two polysiloxanes functionalized with both cycloaliphatic epoxy and triclosan were synthesized using hydrosilylation. The functionalized polysiloxanes, with varied concentration of pendant triclosan, were used to produce UV-curable coatings with reasonably good coating properties. Fourier transform (FT)-Raman spectroscopy showed that the tethered triclosan moieties self-concentrate on the coating surface. Using biological assays, it was determined that the coatings possessed nearly 100% antimicrobial activity toward the Gram-positive bacterium, S. epidermidis, without leaching toxic components. For the Gram-negative bacterium, E. coli, 60-80% reduction in biofilm retention was observed for all the coatings. Interestingly, the coatings were lesser effective in reducing E. coli cell viability suggesting that the tethered triclosan were able to substantially reduce the production of the biofilm extracellular matrix with minimal adverse affect on the bacterial cells attached to the coating surfaces. The high specificity of the coatings toward S. epidermidis indicates that a novel mode of contact-active antimicrobial activity was achieved through the disruption of processes unique to the Gram-positive cell wall. These novel UV-curable coatings have potential applications in inhibiting implantable biomedical device associated infections.

  11. Development of palm oil-based UV-curable epoxy acrylate and urethane acrylate resins for wood coating application

    Energy Technology Data Exchange (ETDEWEB)

    Tajau, Rida; Mahmood, Mohd Hilmi; Salleh, Mek Zah; Salleh, Nik Ghazali Nik [Radiation Processing Technology Division, Malaysian Nuclear Agency (Nuclear Malaysia), Bangi, 43000 Kajang, Selangor (Malaysia); Ibrahim, Mohammad Izzat [Faculty of Science, University of Malaya (UM), 50603 Kuala Lumpur (Malaysia); Yunus, Nurulhuda Mohd [Faculty of Science and Technology, National University Malaysia (UKM), 43600 Bangi, Selangor (Malaysia)

    2014-02-12

    The trend of using renewable sources such as palm oil as raw material in radiation curing is growing due to the demand from the market to produce a more environmental friendly product. In this study, the radiation curable process was done using epoxy acrylate and urethane acrylate resins which are known as epoxidised palm olein acrylate (EPOLA) and palm oil based urethane acrylate (POBUA), respectively. The purpose of the study was to investigate curing properties and the application of this UV-curable palm oil resins for wood coating. Furthermore, the properties of palm oil based coatings are compared with the petrochemical-based compound such as ebecryl (EB) i.e. EB264 and EB830. From the experiment done, the resins from petrochemical-based compounds resulted higher degree of crosslinking (up to 80%) than the palm oil based compounds (up to 70%), where the different is around 10-15%. The hardness property from this two type coatings can reached until 50% at the lower percentage of the oligomer. However, the coatings from petrochemical-based have a high scratch resistance as it can withstand at least up to 3.0 Newtons (N) compared to the palm oil-based compounds which are difficult to withstand the load up to 1.0 N. Finally, the test on the rubber wood substrate showed that the coatings containing benzophenone photoinitiator give higher adhesion property and their also showed a higher glosiness property on the glass substrate compared to the coatings containing irgacure-819 photoinitiator. This study showed that the palm oil coatings can be a suitable for the replacement of petrochemicals compound for wood coating. The palm oil coatings can be more competitive in the market if the problems of using high percentage palm oil oligomer can be overcome as the palm oil price is cheap enough.

  12. Development of palm oil-based UV-curable epoxy acrylate and urethane acrylate resins for wood coating application

    Science.gov (United States)

    Tajau, Rida; Ibrahim, Mohammad Izzat; Yunus, Nurulhuda Mohd; Mahmood, Mohd Hilmi; Salleh, Mek Zah; Salleh, Nik Ghazali Nik

    2014-02-01

    The trend of using renewable sources such as palm oil as raw material in radiation curing is growing due to the demand from the market to produce a more environmental friendly product. In this study, the radiation curable process was done using epoxy acrylate and urethane acrylate resins which are known as epoxidised palm olein acrylate (EPOLA) and palm oil based urethane acrylate (POBUA), respectively. The purpose of the study was to investigate curing properties and the application of this UV-curable palm oil resins for wood coating. Furthermore, the properties of palm oil based coatings are compared with the petrochemical-based compound such as ebecryl (EB) i.e. EB264 and EB830. From the experiment done, the resins from petrochemical-based compounds resulted higher degree of crosslinking (up to 80%) than the palm oil based compounds (up to 70%), where the different is around 10-15%. The hardness property from this two type coatings can reached until 50% at the lower percentage of the oligomer. However, the coatings from petrochemical-based have a high scratch resistance as it can withstand at least up to 3.0 Newtons (N) compared to the palm oil-based compounds which are difficult to withstand the load up to 1.0 N. Finally, the test on the rubber wood substrate showed that the coatings containing benzophenone photoinitiator give higher adhesion property and their also showed a higher glosiness property on the glass substrate compared to the coatings containing irgacure-819 photoinitiator. This study showed that the palm oil coatings can be a suitable for the replacement of petrochemicals compound for wood coating. The palm oil coatings can be more competitive in the market if the problems of using high percentage palm oil oligomer can be overcome as the palm oil price is cheap enough.

  13. Ultraviolet (UV)-Curable Coatings for Aerospace Applications

    Science.gov (United States)

    2012-08-31

    unlimited. PA Release #: 88ABW-2014-5955 Aircraft substrates may be made of aluminum, steel, other metallic alloys , or non-metallic composite...Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic, Nonconductive Coatings Applied to Non- Ferrous Metals. Three or more thickness readings, per...Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic, Nonconductive Coatings Applied to Non- Ferrous Metals All

  14. Chemicals: UV-curable coating for aluminum can production

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-09-29

    Fact sheet on curing aluminum can coatings written for the NICE3 Program. Coors Brewing Company has been using ultraviolet (UV) light curing technology on its aluminum beverage cans for 25 years. The company is now looking to share its cost-saving technology with other aluminum can producers. Traditional curing methods for creating external decorations on cans rely on convective-heat ovens to cure ink and over-varnish coatings. These thermal-curing methods require large amounts of energy and money, and can have unintended environmental impacts. Coors' technique uses coating materials that cure when exposed to UV light, thereby eliminating the expensive heat treatments used by conventional coating methods. Additionally, the UV-coating process creates much lower emissions and a smaller pollution waste stream than rival thermal processes because it requires much less solvent than thermal processes. This technology can be used not only in the aluminum can industry, but in the automotive, airline, wood, paper, and plastics industries, as well.

  15. Synthesis of poly(methyl urethane) acrylate oligomer using 2-isocyanatoethyl methacrylate for UV curable coating.

    Science.gov (United States)

    Park, M N; Oh, S W; Ahn, B H; Moon, M J; Kang, Y S

    2009-02-01

    The poly(methyl urethane) acrylate oligomer was obtained by the reaction of methyl acrylate oligomer and 2-isocyanatoethyl methacrylate. Synthesis of poly(methyl urethane) acrylate oligomer was done with 2-mercaptoethanol (2-MEOH), methyl acrylate, 2,2'-azobisisobutyronitrile (AIBN, initiator) and dibutyltin dilaurate as a catalyst. Then 2-MEOH was used for functional chain transfer agent. The structure and property of the synthesized oligomers were characterized by FT-IR, FT-NMR, rheometer, and DSC. In this study, by synthetic method including the addition of 2-isocyanatoethyl methacrylate, thermal behavior of synthesized material was improved more than that reported in the previous study. Poly(methyl urethane) oligomer can be used for UV curable coatings, inks and adhesives. UV curable coating have high resistance against weather, ozone, aging, frictional wear, and heat. Besides they can absorb the shock and resist rust according to the thickness of film. It is used as an adhesive, paint, optical fiber coating agent, and waterproof agent because of these advantages at the present time.

  16. One-step surface selective modification of UV-curable hard coatings with photochemical metal organics

    Science.gov (United States)

    Lee, Yoon Kwang; Park, Chang-Sun; Park, Hyung-Ho

    2016-12-01

    An organic-inorganic hybrid bi-layer film with a selective distribution of inorganic components was synthesized from a one-pot process of UV irradiation. A photochemical metal oxide precursor (Sr 2-ethylhexanoate) varying from 0 to 4 wt% was dispersed in UV-curable coating materials. Under UV exposure, the bi-layer started reacting simultaneously but at different rates due to differences in the two UV-condensable components' reactivity. The effects of the dispersed inorganic component on the surface morphology and mechanical properties were investigated by atomic force microscopy and nanoindentation, respectively. The reaction process and rates were studied from linkage change using Fourier transform infrared spectroscopy at various UV exposure times (0-30 min). The elemental distribution and the interface on the coating layer were characterized by X-ray photoelectron spectroscopy from Ar etching, revealing continuous and gradual composition changes in depth. The results showed that a flattened and surface-selectively hardened SrO containing the coating film could be obtained by this simple process. Consequently, a small ratio of photochemical metal oxide reinforced the organic hard coating film's mechanical properties through the formation of an effective SrO top layer.

  17. UV-Curable Coating Process on CMYK-Printed Duplex Paperboard, Part I: Mechanical and Optical Properties

    Directory of Open Access Journals (Sweden)

    Mojtaba Soltani

    2013-11-01

    Full Text Available An ultraviolet (UV-curable coating is one of the best finishing methods in the paper and packaging industries for protecting ink layers from physical and mechanical defects. The purpose of this study was to investigate the mechanical and optical properties of CMYK printed paperboard after coating it with the UV-curable varnish. Commercial duplex paperboard (glazed grayback paperboard, 230 g/m2 was printed with a CMYK offset printing process. After conditioning the printed samples, they were coated with a commercial UV-curable varnish (consisting of a liquor-to-solvent ratio of 50:50 using an industrial screen-coating machine. The samples were then dried using a UV lamp in an industrial UV drying machine. The discoloration of the CMYK ink layers was measured spectrophotometrically using CIELab parameters (L*, a*, b*, and ΔE before and after the coating process. The whiteness, brightness, and fold and tear resistance of the ink films were also measured. Color change (ΔE was recorded for all tested samples, and the least amount of discoloration was observed in CYAN ink. The highest variances of the relative optical parameters were found in the MAGENTA, YELLOW, and BLACK ink films, which resulted in yellowing of the coated paperboard. It can therefore be concluded that the coating process significantly decreased the fold and tear resistance of the samples.

  18. Novel epoxy formulations for high energy radiation curable composites

    Science.gov (United States)

    Spadaro, G.; Calderaro, E.; Tomarchio, E.; Dispenza, C.

    2005-03-01

    It has been widely recognised that high energy radiation can be effectively applied to the cure of epoxy resins in applications as composite matrices or structural adhesives with improvements in product quality and/or reduction in production costs. In the presence of suitable initiators, polymerisation of epoxies occurs via cationic mechanism, thus restricting the choice of the resin system components to species which do not contain electron donor groups. The present investigation is aimed to identify suitable co-monomers to be formulated with an epoxy resin, resulting in different cure reaction kinetics and application properties of the cured resin. In particular, four different anhydride types, three dicarboxylic and one tetracarboxylic, have been formulated at the same weight ratio with a diglydilether of bisphenol F and a photo-initiator. Resin samples, irradiated at different integrated doses, have been characterised with solubility tests, dynamic-mechanical thermal analysis and three point flexural tests, showing a response which is strongly affected by the specific chemical structure of the anhydride co-monomer. Post-irradiation thermal treatments carried out on samples irradiated at the lower dose suggest different reaction patterns, with different controlling factors depending on the activation mechanism (temperature or γ-rays).

  19. Analysis of adhesion of radiation curable compositions to polyester substrate. [. gamma. rays or electrons

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, W.K.; Barbery, J.; Gupta, B.S.

    1977-07-01

    Properties of bonds produced by radiation curing of adhesives on polyester film were studied. Investigation of bonding in polyester non-wovens had revealed that adhesion of binders to fibers was weak, which resulted in interfacial failures, judged from electron micrographs. If a binder droplet surrounds a cluster of fibers, tearing of binder took place but fibers still peeled out of droplets with interfacial separation. In order to understand the failure mechanism, a study was carried out on Mylar film bonded with adhesives cured by electron beam or gamma-rays from /sup 60/Co. Mixtures of isodecyl acrylate and methyl methacrylate were copolymerized between Mylar films to produce adhesives with a wide range of glass transition temperatures. Hexanediol diacrylate was added in various amounts to produce different degrees of cross-linking. Small amounts of fumed silica (Cab-O-Sil) were added to thicken the monomers used in the /sup 60/Co experiments. By varying rheological properties in this fashion, a maximum peel force of 3.5 lb/in. was obtained. This value is in line with peel strengths from polyester using commercial, prepolymerized adhesives with solubility parameters similar to those used here delta = 8.3 to 9.3). These results show that the primary reason for the poor adhesion of radiation curable adhesives to polyester is their high degree of cross-linking and that radiation curable adhesives are not basically different from other types, except in cases where their unique properties could be utilized with advantage.

  20. Curing behavior of a UV-curable coating based on urethane acrylate oligomer: the influence of reactive monomers

    Directory of Open Access Journals (Sweden)

    Dapawan Kunwong

    2011-04-01

    Full Text Available A hybrid organic-organic urethane acrylate oligomer was synthesized by the reaction of polypropyleneglycol (PPG,2,4-toluene diisocyanate (TDI and 2-hydroxyethyl methacrylate (HEMA using dibutyltin dilaurate (DBTDL as a catalyst.The urethane acrylate oligomer’s structure was characterized by nuclear magnetic resonance (NMR and Fourier transforminfrared spectroscopy (FT-IR. Two UV-curable coatings were prepared by blending the urethane acrylate oligomer, a reactivemonomer (1,6- hexanediol diacrylate (HDDA or trimethylol propane triacrylate (TMPTA and a photoinitiator (2,2-dimethoxy-2-phenyl acetophenone. The UV curing process of such coatings was monitored by FT-IR and determination of thegel fraction. It was found that as the UV dose increased, the specific peaks at 1635 cm-1 and 810 cm-1, related to the carboncarbondouble (C=C bond, decreased. Gel fraction of the cured coating film was found to increase with increasing radiationtime. Thermal properties of the cured coating were also investigated using differential scanning calorimetry (DSC andthermal gravimetric analysis (TGA.

  1. Solventless visible light-curable coating: I. Critical formulation and processing parameters.

    Science.gov (United States)

    Bose, Sagarika; Bogner, Robin H

    2010-06-30

    Film coating is generally accomplished by spraying polymers dissolved in solvents onto a cascading bed of tablets. The limitations associated with the use of solvents (both aqueous and organic) can be overcome by the use of solventless coating technologies. In this proposed solventless photocurable film coating system, each layer of coating onto the pellets (non-pareil beads) was formed using liquid photocurable monomer, powdered pore-forming agents, photosensitizers and photoinitiators in a mini-coating pan and later cured by visible light. Yield, coating efficiency, variation in color, diameter and roundness were determined for each batch to evaluate process efficiency and coating quality. It was found that the ratio (S/L ratio) of the amount of solid (S) pore-forming agent to volume of liquid (L) monomer, particle size and type of the pore-forming agent, concentration of initiator, and total exposure (light intensity x exposure time) of light were critical formulation and processing parameters for the process. Using lactose as a pore-forming agent, an optimum ratio of pore-forming agent to photocurable polymer was 1.8-3.0 to achieve good process efficiency and uniformity. The ratio was sensitive to particle size and type of pore-forming agent.

  2. UV-Curable Hybrid Nanocomposite Coating to Protect Tether Polymer Materials Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To address the NASA need for coatings to protect and strengthen tether materials for Momentum-exchange Electrodynamic Reboost (MXER) technology, Luminit, LLC,...

  3. Size-Dependent Filling Behavior of UV-Curable Di(meth)acrylate Resins into Carbon-Coated Anodic Aluminum Oxide Pores of around 20 nm.

    Science.gov (United States)

    Nakagawa, Masaru; Nakaya, Akifumi; Hoshikawa, Yasuto; Ito, Shunya; Hiroshiba, Nobuya; Kyotani, Takashi

    2016-11-09

    Ultraviolet (UV) nanoimprint lithography is a promising nanofabrication technology with cost efficiency and high throughput for sub-20 nm size semiconductor, data storage, and optical devices. To test formability of organic resist mask patterns, we investigated whether the type of polymerizable di(meth)acrylate monomer affected the fabrication of cured resin nanopillars by UV nanoimprinting using molds with pores of around 20 nm. We used carbon-coated, porous, anodic aluminum oxide (AAO) films prepared by electrochemical oxidation and thermal chemical vapor deposition as molds, because the pore diameter distribution in the range of 10-40 nm was suitable for combinatorial testing to investigate whether UV-curable resins comprising each monomer were filled into the mold recesses in UV nanoimprinting. Although the UV-curable resins, except for a bisphenol A-based one, detached from the molds without pull-out defects after radical photopolymerization under UV light, the number of cured resin nanopillars was independent of the viscosity of the monomer(s) in each resin. The number of resin nanopillars increased and their diameter decreased as the number of hydroxy groups in the aliphatic diacrylate monomers increased. It was concluded that the filling of the carbon-coated pores having diameters of around 20 nm with UV-curable resins was promoted by the presence of hydroxy groups in the aliphatic di(meth)acrylate monomers.

  4. Influence of sample composition and processing parameters on the UV cure of clear coatings

    Science.gov (United States)

    Ruiz, C. S. B.; Machado, L. D. B.; Volponi, J. E.; Pino, E. S.

    2003-08-01

    Photocurable systems consist of functional macromolecules, which undergo polymerization and a photoinduced crosslinking reaction under UV irradiation. Radiation-curable coatings have gained importance because they are environmentally friendly and save more energy than conventional heat-curable processes. The performance of UV-curable coatings depends on their formulation and cure quality. The quality of UV radiation cure depends on lamp characteristics, photoinitiator (PI) content, film thickness, curing environment, substrate and temperature. The aim of this study was to evaluate the influence of coating thickness and UV radiation dose, as well as coating characteristics such as PI content and stabilizer additive composition, on the curing process.

  5. Progress on the research of modification of UV-curable waterborne polyurethane-acrylate coating%UV固化水性聚氨酯丙烯酸酯涂料改性的研究进展

    Institute of Scientific and Technical Information of China (English)

    徐吉成; 邱凤仙; 蒋艳; 庄甜; 徐滨滨

    2014-01-01

    Ultraviolet (UV)curable waterborne polyurethane-acrylate is a kind of functional environmental protec-tion coatings.The UV curing technology and waterborne polyurethane-acrylate coatings are introduced.The modifi-cation of UV-curable waterborne polyurethane-acrylate coating is reviewed,and its application prospect and devel-opment trend are prospected.%概述紫外光的固化原理与水性聚氨酯丙烯酸酯涂料的性能,综述UV固化水性聚氨酯丙烯酸酯涂料氟、有机硅、环氧树脂及超支化等改性的最新研究进展,展望应用前景与发展趋势。

  6. Applications of Novel Light Stabilizers for Waterborne UV Curable Coatings%新型光稳定剂产品应用于水性光固化涂料的研究

    Institute of Scientific and Technical Information of China (English)

    杨永吉; 黄世承; 宋宇书; 邱晓芳; 简智娴; 黄耀兴

    2013-01-01

      水性光固化涂料已解决了使用传统紫外光固化涂料所释放VOC的问题,而环保型涂料所遭遇的挑战之一,是需要光稳定剂来保护涂料预防光劣化产生。针对水性光固化涂料开发了一种新型复配型光稳定剂EVERSORB AQ7,试验结果显示:针对3种不同类型光稳定剂添加至2种不同类型溶液-水和水性光固化树脂中进行分散过滤试验,EVERSORB AQ7分散效果最好,并且不会对光固化速度产生负效冲击,另外根据实验室人工加速老化试验结果显示,增加EVERSORB AQ7在水性光固化涂料中的有效浓度,可以增强相对的保护效果,增加涂料的膜厚可以得到某种程度的保护效果。茵R茵R茵R%Waterborne UV curable coatings-the green coatings-have been developed to replace conventional UV curable coatings with VOC emissions. It could be a challenge when light stabilizers are required to protect coatings to UV degradation.EVERSORB AQ7, a blend of UV absorber and HALS, is developed specifically for waterborne UV curable coats. This paper is a comparison study of three different light stabilizers to disperse in water and waterborne epoxy coating. Design of Experiment (DOE) was used in this study. Test data showed that EVERSORB AQ7 in a waterborne clear UV curable coating would not have negative impacts to cure speed. The results confirmed that by increasing the concentration of EVERSORB AQ7 in the top coat can effectively protect from UV light degradation. Furthermore, data also showed that by increasing the coating thickness, the weather-ability of coating can also be improved to some degrees.

  7. Application of Photosensitive Microgel in UV Curable Electrodeposition Coatings%光敏性微凝胶在光固化电泳涂料中的应用

    Institute of Scientific and Technical Information of China (English)

    刘仁; 安丰磊; 张胜文; 董雅洁; 刘晓亚

    2012-01-01

    将自制的光敏性微凝胶添加到光固化电泳涂料中,以进一步提升光固化电沉积体系的综合性能.研究了光敏性微凝胶添加量对光固化电沉积体系电泳过程、电沉积膜光固化行为、固化膜玻璃化转变温度及机械性能等的影响.研究结果表明:当光敏性微凝胶添加量不大于6%时,光敏性微凝胶的添加并不影响电沉积过程的有效进行,且随着光敏性微凝胶添加量的增大,光固化电泳涂料固化膜的玻璃化转变温度、贮能模量及拉伸强度等性能均得到有效提升.%Photosensitive microgel was added into the title UV curable coatings to enhance the comprehensive performance. The effect of photosensitive microgel dosage on the electrodeposition process,UV curing behavior,the glass transition temperature and mechanic properties was investigated. The results showed that the addition of photosensitive microgel would not affect the electrodeposition process of electrodeposition coatings when the photosensitive microgel amount was less than 6% ,and the glass transition temperature,the storage modulus and tensile strength of UV cured film were enhanced by the increase of photosensitive microgel dosage.

  8. Investigation of Coating Performance of UV-Curable Hybrid Polymers Containing 1H,1H,2H,2H-Perfluorooctyltriethoxysilane Coated on Aluminum Substrates

    Directory of Open Access Journals (Sweden)

    Mustafa Çakır

    2017-03-01

    Full Text Available This study describes preparation and characterization of fluorine-containing organic-inorganic hybrid coatings. The organic part consists of bisphenol-A glycerolate (1 glycerol/phenol diacrylate resin and 1,6-hexanediol diacrylate reactive diluent. The inorganically rich part comprises trimethoxysilane-terminated urethane, 1H,1H,2H,2H-perfluorooctyltriethoxysilane, 3-(trimethoxysilyl propyl methacrylate and sol–gel precursors that are products of hydrolysis and condensation reactions. Bisphenol-A glycerolate (1 glycerol/phenol diacrylate resin was added to the inorganic part in predetermined amounts. The resultant mixture was utilized in the preparation of free films as well as coatings on aluminum substrates. Thermal and mechanical tests such as DSC, thermo-gravimetric analysis (TGA, and tensile and shore D hardness tests were performed on free films. Water contact angle, gloss, Taber abrasion test, cross-cut and tubular impact tests were conducted on the coated samples. SEM examination and EDS analysis was performed on the fractured surfaces of free films. The hybrid coatings on the aluminum sheets gave rise to properties such as moderately glossed surface; low wear rate and hydrophobicity. Tensile strength of free films increased with up to 10% inorganic content in the hybrid structure and this increase was approximately three times that of the control sample. As expected; the % strain value decreased by 17.3 with the increase in inorganic content and elastic modulus values increased by a factor of approximately 6. Resistance to ketone-based solvents was proven and an increase in hardness was observed as the ratio of the inorganic part increased. Samples which contain 10% sol–gel content were observed to provide optimal properties.

  9. Molecular Design, Graft Polymerization and Performance Evaluation of Radiation Curable Flame Retardant Monomers Derived from Phosphorus-Nitrogen Systems

    Science.gov (United States)

    Edwards, Brian Tyndall

    The textile industry is constantly seeking new technologies to make its production more efficient, economical and environmentally friendly. An exciting new strategy to impart value-added functional finishes to textiles is the use of radiation, such as ultraviolet (UV) light, to drive the polymerization of monomers onto the surface of the substrates. These grafted polymeric layers provide the fiber or fabric with interesting new properties, such as antimicrobial behavior, water and oil repellency or flame retardancy. With the aid of a photoinitiator, UV curing can take place very rapidly and the process is waterless and uses less energy than traditional textile wet processing. With these thoughts in mind, this research explores the molecular design, synthesis, UV induced graft polymerization and performance evaluation of nine phosphorus-based flame retardant monomers for cellulosic cotton substrates. All monomers in this work were easily prepared using one-pot reactions procedures. With the assistance of Irgacure 819 photoinitiator, seven of the nine monomers were shown to simultaneously graft and polymerize onto the surface of cotton fabrics under UV radiation. JMPRTM Pro 10 software was used to explore the effect of variables, such as monomer concentration, photoinitiator concentration and UV exposure time, on the yield of the grafted polymeric layer. Burn testing of the treated fabrics in the vertical, 45° and horizontal orientations showed that all nine monomers were effective flame retardants that function via the condensed phase mechanism by encouraging the formation of nonflammable char. These burn test results were validated by thermogravimetric analysis, which demonstrated quantitatively that all nine monomers strongly promote the generation of a protective char. Finally, scanning electron microscopy was used to examine the surface morphology of the treated fabrics and visualize the grafted polymeric layer.

  10. 紫外光固化漆酚基纳米复合涂料性能的对比分析%Properties Comparative Analysis of UV-curable Urushiol Nanocomposite Coating

    Institute of Scientific and Technical Information of China (English)

    阮亿明

    2015-01-01

    The UV-curable technology was combined with organic/ inorganic hybrid nano materials preparation technology, applied renewable natural lacquer as the main raw material, four species composite coatings of Nano SiO2 / TiO2 / ZnO / OMMT were prepared by UV curing urushiol and UV curing urushiol. The conventional mechanical properties, UV resistance, solvent resistance and chemical resistance properties of urushiol formaldehyde condensates, were analyzed. The results showed that the properties of UV-curable urushiol and its four nano-composite coatings were improved greatly.%将紫外光固化技术与有机/无机纳米杂化材料制备技术相结合,以可再生天然生漆为主要原料,制得了紫外光固化漆酚和紫外光固化漆酚基纳米SiO2/TiO2/ZnO/OMMT的4种复合涂料.对比分析了其与漆酚甲醛缩聚物的常规物理机械性能、抗紫外线性能、抗溶剂性和耐化学介质性能.结果表明,紫外光固化漆酚和以其为基础的4种纳米复合涂料的各项性能均较漆酚甲醛缩聚物有较大提高.

  11. Radiation curing in the eighties

    Energy Technology Data Exchange (ETDEWEB)

    Vrancken, A. (UCB, Drogenbos (Belgium). Chemical Specialities Div.)

    1984-05-01

    The subject is discussed under the headings: introduction; what is radiation curing; history; radiation curable resins (with properties of products); ultraviolet and electron beam curing; photoinitiation and the ultraviolet light curing process; electron beam curing (initiation; electron beam accelerators); end uses (graphic arts; wood finishing; paper upgrading; adhesives; metal finishing; electronic chemical; floor coatings).

  12. Is autism curable?

    Science.gov (United States)

    Bölte, Sven

    2014-10-01

    Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder of multifactorial origin. Today, ASD is generally not curable, although it is treatable to a varying degree to prevent worse outcomes. Some reports indicate the possibility of major improvements or even recovery in ASD. However, these studies are based on scientific shortcomings, and the lack of a clear definition of 'cure' in ASD further compromises interpretation of research findings. The development of animal models and decreasing costs of genome sequencing provide new options for treatment research and individualized medicine in ASD. This article briefly reviews several issues related to the question whether there is recovery from ASD, starting with a short overview of the presumed aetiologies.

  13. Engineering of ultra-violet ray curable PSAs%UV固化压敏胶工程

    Institute of Scientific and Technical Information of China (English)

    吕凤亭

    2012-01-01

    压敏胶及其制品工业需要向节能、减排、绿色方面发展.其中以UV固化压敏胶制品的工业化最为先进.UV固化压敏胶工业化,即UV固化压教胶工程分为4部分予以实现:1)UV固化压敏胶制备;2)UV固化辐照设备设计;3)UV固化压敏胶涂布生产线的建造和改造;4)工厂管理和成本测算.%Pressure-sensitive adhesive products industry needs to save energy,reduce emission and realize green. Wherein,the industrialization of the UV curable PSA products is the most prominent.The industrialization, that is the engineering, of the UV curable PSAs is divided into four sections: 1. The preparation of the UV curable PSAs,2. The designment of UV radiation devices,3. The construction and modification of coating production line,and,4.the factory management and the cost estimates.

  14. The Lattice and Thermal Radiation Conductivity of Thermal Barrier Coatings

    Science.gov (United States)

    Zhu, Dongming; Spuckler, Charles M.

    2008-01-01

    The lattice and radiation conductivity of thermal barrier coatings was evaluated using a laser heat flux approach. A diffusion model has been established to correlate the apparent thermal conductivity of the coating to the lattice and radiation conductivity. The radiation conductivity component can be expressed as a function of temperature and the scattering and absorption properties of the coating material. High temperature scattering and absorption of the coating systems can also be derived based on the testing results using the modeling approach. The model prediction is found to have good agreement with experimental observations.

  15. UV固化TiO2光催化涂料的制备及性能研究%Preparation and performance study of UV-curable TiO2 photocatalyst coating

    Institute of Scientific and Technical Information of China (English)

    齐家鹏; 姚伯龙; 张国标; 姜峻; 李巧萍

    2015-01-01

    以六亚甲基二异氰酸酯(HDI)三聚体、二乙醇胺、甲基丙烯酸缩水甘油酯(GMA)为主要原料合成了低分子量多官能度 UV固化预聚物。以该预聚物为成膜树脂,与锐钛型TiO2乙醇分散液混合,制备了UV固化TiO2光催化涂层。采用傅里叶变换红外光谱、1H–核磁共振、凝胶色谱等对合成预聚物的结构和性能进行表征。探讨了 TiO2含量对涂层附着力、铅笔硬度、耐水性、水接触角和光照稳定性的影响,研究了在模拟太阳光照下不同TiO2含量UV固化涂层对水中亚甲基蓝的光催化降解作用。结果表明, TiO2含量为0.9%时,涂层具有较好的机械性能和耐水性,且2 h就可使亚甲基蓝溶液褪色。通过热重分析仪测得涂层的起始分解温度为220°C,热稳定性较好。%A multifunctional UV-curable prepolymer with low molecular weight was synthesized by using hexamethylene diisocyanate (HDI) trimer, diethanolamine, and glycidyl methacrylate (GMA) as main raw materials, and then used as film-forming resin to prepare a UV-curable TiO2 photocatalyst coating by mixing with ethanol dispersion of anatase TiO2. The structure and properties of the prepolymer were characterized by infrared spectroscopy, 1H-nuclear magnetic resonance, and gel permeation chromatography. The effect of TiO2 amount on the adhesion strength, hardness, water resistance, water contact angle, and light stability of the coating were discussed. The photocatalytic degradations of methylene blue in water by the UV-cured coatings with different contents of TiO2 under simulated solar light were examined. The results showed that the coating with 0.9%TiO2 exhibits good mechanical properties and water resistance, and makes methylene blue solution fade in just 2 h. The result of thermogravimetric analysis (TGA) indicated that the coating has an initial decomposition temperature of 220 °C, showing good thermal stability.

  16. Corrosion Finishing/Coating Systems for DoD Metallic Substrates Based on Non-Chromate Inhibitors and UV Curable, Zero VOC Materials

    Science.gov (United States)

    2010-08-01

    After the 3000-hour exposure period get photographs taken of the test panels. Strip one of the test panels with Turco 5469 or equivalent paint stripper...test panels. Strip one of the test panels with Turco 5469 or equivalent paint stripper and photograph the stripped panels. Xenon Arc Weather...alkaline cleaning temperature on coating deposition and corrosion performance. The alkaline cleaner used, Turco 4215-NLCT from Henkel Corp., has a

  17. Radiation pressure efficiency measurements of nanoparticle coated microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soo Y. [National Research Council, Research Associateship Programs, 500 Fifth Street NW (Keck 568), Washington, D.C. 20001 (United States); Taylor, Joseph D.; Ladouceur, Harold D.; Hart, Sean J.; Terray, Alex, E-mail: terray@nrl.navy.mil [Naval Research Laboratory, Chemistry Division, Bioanalytical Chemistry, Code 6112, 4555 Overlook Avenue S.W., Washington, D.C. 20375 (United States)

    2013-12-02

    Experimental measurements of the radiation pressure efficiency (Q{sub pr}) for several microparticles have been compared to theoretical calculations extrapolated from the Bohren-Huffman code for Mie scattering of coated particles. An increased shift of the Q{sub pr} parameter was observed for 2 μm SiO{sub 2} core particles coated with nanoparticles of higher refractive indices. Coatings of 14 nm melamine particles were found to increase the Q{sub pr} parameter 135 times over similar coatings using SiO{sub 2} particles of the same size. While a coating of 100 nm polystyrene particles also showed a significant increase, they did not agree well with theoretical values. It is hypothesized that other factors such as increased scatter, drag, and finite coating coverage are no longer negligible for coatings using nanoparticles in this size regime.

  18. Radiation pressure efficiency measurements of nanoparticle coated microspheres

    Science.gov (United States)

    Kim, Soo Y.; Taylor, Joseph D.; Ladouceur, Harold D.; Hart, Sean J.; Terray, Alex

    2013-12-01

    Experimental measurements of the radiation pressure efficiency (Qpr) for several microparticles have been compared to theoretical calculations extrapolated from the Bohren-Huffman code for Mie scattering of coated particles. An increased shift of the Qpr parameter was observed for 2 μm SiO2 core particles coated with nanoparticles of higher refractive indices. Coatings of 14 nm melamine particles were found to increase the Qpr parameter 135 times over similar coatings using SiO2 particles of the same size. While a coating of 100 nm polystyrene particles also showed a significant increase, they did not agree well with theoretical values. It is hypothesized that other factors such as increased scatter, drag, and finite coating coverage are no longer negligible for coatings using nanoparticles in this size regime.

  19. Water-soluble UV curable urethane methyl acrylate coating:preparation and properties

    Institute of Scientific and Technical Information of China (English)

    魏燕彦; 罗英武; 李宝芳; 李伯耿

    2004-01-01

    Two kinds of water-soluble and ultraviolet (UV) curable oligomers were synthesized and characterized. The oligomers were evaluated as resins for water-based UV curable coating. The rheology of the two oligomers' aqueous so-lutions was investigated in terms of solid fraction, pH dependence, and temperature dependence. The solutions were found to be Newtonian fluid showing rather low viscosity even at high solid fraction of 0.55. The drying process of the coatings and the properties of the cured coatings were studied by comparing them with water-dispersed UV-curable polyurethane methyl acrylate. It was evident that the water-soluble coating dried more slowly; and that the overall properties were inferior to those of the water-dispersed coating.

  20. 软段改性 UV 固化水性聚氨酯涂料的合成与性能%Synthesis and Properties of Soft Segment Modified UV-curable Waterborne Polyurethane Coatings

    Institute of Scientific and Technical Information of China (English)

    邓剑如; 王祝愿; 李尚钰

    2016-01-01

    以阳离子共聚合的方法,通过改变四氢呋喃(THF)和环氧氯丙烷(ECH)的配比,调整起始剂用量,合成出系列数均相对分子质量在2000左右的端羟基共聚醚.以此端羟基共聚醚作为软段,合成出系列改性的水性光固化聚氨酯乳液,用FTIR验证产物结构.结果表明:随着环氧氯丙烷配比的增加,软段中强极性卤素原子增多,乳液储存稳定性良好,固化膜的拉伸强度由4.6 M Pa逐渐增加至6.7 M Pa ,断裂伸长率从162%降至113%,热稳定性逐渐变好,当T H F和EC H的配比提高到1∶1时,5%,10%的失重温度分别为200℃和275℃,比改性之前的5%,10%失重温度164℃,220℃提高了36℃和55℃;涂层的附着力显著提高至1级,硬度也有所增加,耐冲击性能优异.%Series of the hydroxyl‐terminated co‐polyethers whose molecular weight is around 2 000 were synthesized by controlling the rate of T HF and ECH and the dosage of initintor .Varied types of modified UV curable waterborne polyurethane emulsions were synthesized by using the co‐polyethers acting as soft segment ,and the corresponding product structures were characterized by using FTIR .The results have shown that :with the increasing ratio of epoxy chloropropane ,the strong polarity halogen atoms in the soft segment increases w hile the tensile strength of curable film changes from 4 .6 MPa to 6 .7 MPa and the e‐longation at break reduces from 162% to 113% .When the ratio of THF and ECH grows to be 1∶1 ,the weightlessness temperature of 5% and 10% increases from 164 ℃ to 200 ℃ and 220 ℃ to 275 ℃ .In addi‐tion ,the adhesion of the coating significantly increases to 1 level ,also the hardness and impact resistance performance improves .

  1. Plasma Processes : Plasma sprayed alumina coatings for radiation detector development

    Indian Academy of Sciences (India)

    Mary Alex; V Balagi; K R Prasad; K P Sreekumar; P V Ananthapadmanabhan

    2000-11-01

    Conventional design of radiation detectors uses sintered ceramic insulating modules. The major drawback of these ceramic components is their inherent brittleness. Ion chambers, in which these ceramic spacers are replaced by metallic components with plasma spray coated alumina, have been developed in our Research Centre. These components act as thin spacers that have good mechanical strength as well as high electrical insulation and replace alumina insulators with the same dimensions. As a result, the design of the beam loss monitor ion chamber for CAT could be simplified by coating the outer surface of the HT electrode with alumina. One of the chambers developed for isotope calibrator for brachytherapy gamma sources has its outer aluminium electrode (60 mm dia × 220 mm long) coated with 250 thick alumina (97%) + titania (3%). In view of potential applications in neutron-sensitive ion chambers used in reactor control instrumentation, studies were carried out on alumina 100 to 500 thick coatings on copper, aluminium and SS components. The electrical insulation varied from 108 ohms to 1012 ohms for coating thicknesses above 200 . The porosity in the coating resulted in some fall in electrical insulation due to moisture absorption. An improvement could be achieved by providing the ceramic surface with moisture-repellent silicone oil coating. Irradiation at Apsara reactor core location showed that the coating on aluminium was found to be unaffected after exposure to 1017 nvt fluence.

  2. A novel epoxy methacrylate resin containing phthalazinone moiety for UV coatings

    Institute of Scientific and Technical Information of China (English)

    Yan Kou; Jin Yan Wang; Xi Gao Jian

    2007-01-01

    A novel phthalazinone modified epoxy acrylate resin for the high temperature resistant ultravioet (UV) curable coating was synthesized. The methacrylated epoxy resins obtained were utilized to UV radiation curing by taking 2.5% (wt%) of photoinitiator in combination with 20% (wt%) of diluent, and generated the interpenetraring polymer networks. The cured film had good thermal and chemical stability.

  3. Radiative absorption enhancement from coatings on black carbon aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Xinjuan; Wang, Xinfeng; Yang, Lingxiao [Environmental Research Institute, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Chen, Bing, E-mail: bingchen@sdu.edu.cn [Environmental Research Institute, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Chen, Jianmin, E-mail: jmchen@sdu.edu.cn [Environmental Research Institute, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Andersson, August; Gustafsson, Örjan [Department of Environmental Science and Analytical Chemistry (ACES) and the Bolin Centre for Climate Research, Stockholm University, SE-10691 Stockholm (Sweden)

    2016-05-01

    The radiative absorption enhancement of ambient black carbon (BC), by light-refractive coatings of atmospheric aerosols, constitutes a large uncertainty in estimates of climate forcing. The direct measurements of radiative absorption enhancement require the experimentally-removing the coating materials in ambient BC-containing aerosols, which remains a challenge. Here, the absorption enhancement of the BC core by non-absorbing aerosol coatings was quantified using a two-step removal of both inorganic and organic matter coatings of ambient aerosols. The mass absorption cross-section (MAC) of decoated/pure atmospheric BC aerosols of 4.4 ± 0.8 m{sup 2}g{sup −1} was enhanced to 9.6 ± 1.8 m{sup 2}g{sup −1} at 678-nm wavelength for ambiently-coated BC aerosols at a rural Northern China site. The enhancement of MAC (E{sub MAC}) rises from 1.4 ± 0.3 in fresh combustion emissions to ~ 3 for aged ambient China aerosols. The three-week high-intensity campaign observed an average E{sub MAC} of 2.25 ± 0.55, and sulfates were primary drivers of the enhanced BC absorption. - Highlights: • A method was developed to remove coatings surrounding BC in ambient aerosols. • The MAC of decoated BC of 4.4 was enhanced to 9.6 m{sup 2}g{sup −1} for ambient BC aerosols. • BC radiative forcing in the ambient atmosphere was enhanced by a factor of ~ 2. • BC absorption enhancement peaked in day time driven by secondary sulfate.

  4. Smart Surfaces: New Coatings & Paints with Radiation Detection Functionality

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, J; Choi, J

    2007-03-12

    Paints are being developed and tested that might ultimately be able to detect radiological agents in the environment by incorporating special pigments into an organic polymeric binder that can be applied as a paint or coatings. These paints detect radioactive sources and contaminants with inorganic or organic scintillation or thermo-luminescent pigments, which are selected based upon the radiation ({alpha}, {beta}, {gamma} or n) to be detected, and are shown in Figure 1.

  5. Weathering of coil-coatings: UV radiation and thermal effects

    Directory of Open Access Journals (Sweden)

    Castela, A. S.

    2003-12-01

    Full Text Available The effect of heat and of QUV ageing on coil coatings was tested by electrochemical impedance, and the results compared with surface analysis of the polymers by FTIR and XPS. It was shown that UV radiation is more relevant than heat to chemical degradation. A different correlation between water permeation and chemical degradation was observed depending on the coating thickness: for the thinner coatings, the higher UV degradation has corresponded to increased water absorption, whereas in the thicker coating, the bulk effect of heat was more relevant to water permeation.

    El efecto del calor y del envejecimiento, QUV, sobre recubrimiemtos de bobinas se probó mediante la impedancia electroquímica, y los resultados se compararon con análisis superficiales de los polímeros usando FTIR y XPS. Se encontró que la radiación UV es más importante que el calor en la degradación química. Una correlación diferente, entre agua infiltrada y degradación química, se observó, dependiendo del espesor del recubrimiento: para los recubrimientos más delgados, mayor degradación UV correspondió a un incremento de absorción de agua; en cambio, para los recubrimientos más gruesos, el efecto del calor fue más importante para la infiltración del agua.

  6. Iridium-Coated Rhenium Radiation-Cooled Rockets

    Science.gov (United States)

    Reed, Brian D.; Biaglow, James A.; Schneider, Steven J.

    1997-01-01

    Radiation-cooled rockets are used for a range of low-thrust propulsion functions, including apogee insertion, attitude control, and repositioning of satellites, reaction control of launch vehicles, and primary propulsion for planetary space- craft. The key to high performance and long lifetimes for radiation-cooled rockets is the chamber temperature capability. The material system that is currently used for radiation-cooled rockets, a niobium alloy (C103) with a fused silica coating, has a maximum operating temperature of 1370 C. Temperature limitations of C103 rockets force the use of fuel film cooling, which degrades rocket performance and, in some cases, imposes a plume contamination issue from unburned fuel. A material system composed of a rhenium (Re) substrate and an iridium (Ir) coating has demonstrated operation at high temperatures (2200 C) and for long lifetimes (hours). The added thermal margin afforded by iridium-coated rhenium (Ir/Re) allows reduction or elimination of fuel film cooling. This, in turn, leads to higher performance and cleaner spacecraft environments. There are ongoing government- and industry-sponsored efforts to develop flight Ir/ Re engines, with the primary focus on 440-N, apogee insertion engines. Complementing these Ir/Re engine development efforts is a program to address specific concerns and fundamental characterization of the Ir/Re material system, including (1) development of Ir/Re rocket fabrication methods, (2) establishment of critical Re mechanical properly data, (3) development of reliable joining methods, and (4) characterization of Ir/Re life-limiting mechanisms.

  7. Radiation Resistant Hybrid Lotus Effect Photoelectrocatalytic Self-Cleaning Anti-Contamination Coatings Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project will develop radiation resistant hybrid Lotus Effect photoelectrocatalytic self-cleaning anti-contamination coatings for application to Lunar...

  8. NEW HIGHER PERFORMANCE LOW COST SELECTIVE SOLAR RADIATION CONTROL COATINGS

    Energy Technology Data Exchange (ETDEWEB)

    Timothy Ellison; Buddie Dotter; David Tsu

    2003-10-28

    Energy Conversion Devices, Inc., ECD, has developed a new high-speed low-cost process for depositing high quality dielectric optical coatings--Microwave Plasma Enhanced Chemical Vapor Deposition (MPECVD). This process can deposit SiO{sub x} about 10 times faster than the state-of-the-art conventional technology, magnetron sputtering, at about 1/10th the cost. This process is also being optimized for depositing higher refractive index materials such as Si{sub 3}N{sub 4} and TiO{sub 2}. In this program ECD, in collaboration with Southwall Technologies, Inc. (STI), demonstrated that this process can be used to fabricate high performance low cost Selective Solar Radiation Control (SSRC) films for use in the automotive industry. These coatings were produced on thin (2 mil thick) PET substrates in ECD's pilot roll-to-roll pilot MPECVD deposition machine. Such film can be laminated with PVB in a vehicle's windows. This process can also be used to deposit the films directly onto the glass. Such highly selective films, with a visible transmission (T{sub vis}) of > 70% and a shading coefficient of < 60% can significantly reduce the heat entering a car from solar radiation. Consequently, passenger comfort is increased and the energy needed to operate air conditioning (a/c) systems is reduced; consequently smaller a/c systems can be employed resulting in improved vehicle fuel efficiency.

  9. A conductive surface coating for Si-CNT radiation detectors

    Science.gov (United States)

    Valentini, Antonio; Valentini, Marco; Ditaranto, Nicoletta; Melisi, Domenico; Aramo, Carla; Ambrosio, Antonio; Casamassima, Giuseppe; Cilmo, Marco; Fiandrini, Emanuele; Grossi, Valentina; Guarino, Fausto; Angela Nitti, Maria; Passacantando, Maurizio; Santucci, Sandro; Ambrosio, Michelangelo

    2015-08-01

    Silicon-Carbon Nanotube radiation detectors need an electrically conductive coating layer to avoid the nanotube detachment from the silicon substrate and uniformly transmit the electric field to the entire nanotube active surface. Coating material must be transparent to the radiation of interest, and must provide the drain voltage necessary to collect charges generated by incident photons. For this purpose various materials have been tested and proposed in photodetector and photoconverter applications. In this article interface properties and electrical contact behavior of Indium Tin Oxide films on Carbon Nanotubes have been analyzed. Ion Beam Sputtering has been used to grow the transparent conductive layer on the nanotubes. The films were deposited at room temperature with Oxygen/Argon mixture into the sputtering beam, at fixed current and for different beam energies. Optical and electrical analyses have been performed on films. Surface chemical analysis and in depth profiling results obtained by X-ray Photoelectron Spectroscopy of the Indium Tin Oxide layer on nanotubes have been used to obtain the interface composition. Results have been applied in photodetectors realization based on multi wall Carbon Nanotubes on silicon.

  10. A conductive surface coating for Si-CNT radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Valentini, Antonio, E-mail: antonio.valentini@ba.infn.it [Dipartimento di Fisica, Università degli Studi di Bari, Via Orabona 4, 70125 Bari (Italy); Valentini, Marco [INFN, Sezione di Bari, Via Orabona 4, 70126 Bari (Italy); Ditaranto, Nicoletta [Dipartimento di Chimica, Università degli Studi di Bari, Via Amendola 173, 70126 Bari (Italy); Melisi, Domenico [INFN, Sezione di Bari, Via Orabona 4, 70126 Bari (Italy); Aramo, Carla, E-mail: aramo@na.infn.it [INFN, Sezione di Napoli, Via Cintia 2, 80126 Napoli (Italy); Ambrosio, Antonio [CNR-SPIN U.O.S. di Napoli and Dipartimento di Scienze Fisiche, Università degli Studi di Napoli “Federico II”, Via Cintia 2, 80126 Napoli (Italy); Casamassima, Giuseppe [Dipartimento di Fisica, Università degli Studi di Bari, Via Orabona 4, 70125 Bari (Italy); INFN, Sezione di Bari, Via Orabona 4, 70126 Bari (Italy); Cilmo, Marco [INFN, Sezione di Napoli, and Dipartimento di Scienze Fisiche, Università degli Studi di Napoli “Federico II”, Via Cintia 2, 80126 Napoli (Italy); Fiandrini, Emanuele [INFN, Sezione di Perugia, and Dipartimento di Fisica, Università degli Studi di Perugia, Piazza Università 1, 06100 Perugia (Italy); Grossi, Valentina [INFN, Sezione di L’Aquila, and Dipartimento di Scienze Fisiche e Chimiche, Università degli Studi dell’Aquila, Via Vetoio 10 Coppito, 67100 L’Aquila (Italy); and others

    2015-08-01

    Silicon–Carbon Nanotube radiation detectors need an electrically conductive coating layer to avoid the nanotube detachment from the silicon substrate and uniformly transmit the electric field to the entire nanotube active surface. Coating material must be transparent to the radiation of interest, and must provide the drain voltage necessary to collect charges generated by incident photons. For this purpose various materials have been tested and proposed in photodetector and photoconverter applications. In this article interface properties and electrical contact behavior of Indium Tin Oxide films on Carbon Nanotubes have been analyzed. Ion Beam Sputtering has been used to grow the transparent conductive layer on the nanotubes. The films were deposited at room temperature with Oxygen/Argon mixture into the sputtering beam, at fixed current and for different beam energies. Optical and electrical analyses have been performed on films. Surface chemical analysis and in depth profiling results obtained by X-ray Photoelectron Spectroscopy of the Indium Tin Oxide layer on nanotubes have been used to obtain the interface composition. Results have been applied in photodetectors realization based on multi wall Carbon Nanotubes on silicon. - Highlights: • ITO was deposited by Ion Beam Sputtering on MWCNT. • ITO on CNT makes an inter-diffusion layer of the order of one hundred nanometers. • Improvements of quantum efficiency of photon detectors based on CNT with ITO.

  11. In Situ Monitoring of UV-Curing Kinetics of Acrylate Coatings by Combined Ultrasound Reflectometry and Near-Infrared Spectroscopy

    OpenAIRE

    Agarwal, Suman

    2011-01-01

    UV radiation curing is a novel technology in the field of organic coatings. It involves curing of reactive resin using the energy of photons in the wavelength region 200-400 nm. The most attractive feature of this method is its low space, low capital and low energy consumption. Free radical polymerizable acrylate resins are the most commonly used resins in UV curing. The UV curable acrylates are mainly used as protective and decorative coatings. In general curing displays a complex interdepen...

  12. Effect of UV/EB radiation dosages on the properties of nanocomposite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Nik Salleh, Nik Ghazali, E-mail: Nik_Ghazali@nuclearmalaysia.gov.m [Malaysian Nuclear Agency, Block 42, Radiation Curing and Synthesis Group, Bangi, 43000 Kajang, Selangor (Malaysia); Firdaus Yhaya, Mohd; Hassan, Azman; Abu Bakar, Aznizam; Mokhtar, Munirah [Faculty of Chemical and Natural Resources Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor (Malaysia)

    2011-02-15

    The aim of this study was to compare the effects of ultraviolet (UV) and electron beam (EB) radiation on the properties of cured nanocomposite coatings. Surface hardness increased with increase in radiation dosages (number of passes) for all samples. This was due to the increase in crosslinking with increase in radiation dosage. Pendulum hardness, gel content, and thumb twist results were analyzed to choose appropriate curing dosage for both curing techniques. The selected dosages were then used to cure coatings for scratch and abrasion resistance tests. It was found that the UV curing produced coatings with better abrasion resistance, whereas EB curing was a more suitable approach for producing scratch resistance coatings.

  13. Evaluation of UV-permeability and photo-oxidisability of organic ultraviolet radiation-absorbing coatings

    Energy Technology Data Exchange (ETDEWEB)

    Li, Neng; Chen, Yuhe, E-mail: yuhec@sina.com; Bao, Yongjie; Zhang, Zeqian; Wu, Zaixing; Chen, Zhangmin

    2015-03-30

    Highlights: • We investigate organic UV radiation-absorbing coatings for use on bamboo surfaces. • The size of glass exactly inserted into sample cell of UV-Vis spectrophotometer. • A model was made to predict UV absorption of coatings. • We examine carbonyl groups change of coatings after ageing. • Two formulations which could effectively protect coating were obtained. - Abstract: Enhancing the durability of the coatings used on bamboo products is essential for increasing their use in outdoor environments. In this study, we investigated organic UV radiation-absorbing coatings for use on bamboo surfaces. The degree of resistance of the coatings, which contained 2-(2-hydroxy-3-tert-butyl-5-methyl-phenyl)-5-chlorinated benzotriazole (BTZ-1), to UV radiation degradation was determined through spectroscopic analysis. The critical BTZ-1 loading amount was determined by analysing the spectroscopic data. Fourier transform infrared spectroscopy was used to elucidate the relationship between the degree of photooxidation of the coatings and their BTZ-1 concentration. The experimental results showed that the coatings provided a high degree of shielding from UV radiation. The critical loading amount was determined to be 1.82 ± 0.05 g BTZ-1/m{sup 2}. The coatings formed using the formulations that contained 3 and 5 wt% BTZ-1 exhibited the lowest degree of photooxidation after exposure to UV radiation.

  14. The Lattice and Thermal Radiation Conductivity of Thermal Barrier Coatings: Models and Experiments

    Science.gov (United States)

    Zhu, Dongming; Spuckler, Charles M.

    2010-01-01

    The lattice and radiation conductivity of ZrO2-Y2O3 thermal barrier coatings was evaluated using a laser heat flux approach. A diffusion model has been established to correlate the coating apparent thermal conductivity to the lattice and radiation conductivity. The radiation conductivity component can be expressed as a function of temperature, coating material scattering, and absorption properties. High temperature scattering and absorption of the coating systems can be also derived based on the testing results using the modeling approach. A comparison has been made for the gray and nongray coating models in the plasma-sprayed thermal barrier coatings. The model prediction is found to have a good agreement with experimental observations.

  15. Novel cationic UV-curable cathodic electrophoretic coatings with pendant amine salt%侧基含铵盐的新型阳离子UV固化阴极电泳涂料

    Institute of Scientific and Technical Information of China (English)

    潘小坚; 孙东成

    2015-01-01

    将叔胺位于主链的 N-甲基二乙醇胺(MDEA)和叔胺位于侧基的7,12-二氧-3,16-二氮-3,16-二乙基-5,14-十八二醇(DDDOD)分别作为亲水单体,与聚己内酯二元醇(PCL)、异佛尔酮二异氰酸酯(IPDI)等反应,制备聚氨酯分散体。通过聚氨酯的分散性、分散体平均粒径,比较了亲水基位于聚氨酯主链和侧基的两种单体的亲水性。结果表明,亲水基团位于侧基时,亲水效果比位于主链的好。将叔氨基位于侧基的单体DDDOD作为亲水单体,与PCL、IPDI反应,制备了聚氨酯,加入UV固化单体,分散得到UV固化的阴极电泳涂料。研究了涂料的乳液性能和UV固化后双键转化率和膜性能。%N-Methyldiethanolamine (MDEA) bearing main chain tertiary amine and 7,12-dioxa-3,16-diaza- 3,16-diethyl-5,14-octadecanediol (DDDOD) bearing pendant tertiary amine were used as the hydrophilic monomers, respectively to prepare polyurethane dispersions. Hydrophilcity of the two hydrophilic monomers was compared by the dispersibilities of the polyurethanes and mean diameters of the dispersions. The results showed that DDDOD had a better hydrophilcity than MDEA, revealing that hydrophilic monomer with pendant tertiary amine had a superior hydrophilic ability than that with backbone tertiary amine. Polyurethane was prepared by the reaction between DDDOD, poly-caprolaclone glycol(PCL) and isophorone diisocyanate (IPDI). UV-curable monomers were added into the polyurethane and dispersed together. The properties of the dispersions and films were studied. The conversion of carbon-carbon double bonds after UV-curing was analyzed.

  16. Enhancement of heat radiative characteristics of coatings by ultra-attenuation

    Institute of Scientific and Technical Information of China (English)

    Dehong Xia; Yonghong Wu

    2004-01-01

    The absorption process of radiative heat in its transmission medium and the effect of ultra-attenuation on the radiative characteristics are analyzed in detail. A method of ultra-attenuation to enhance the radiative characteristics of the medium is proposed. It is proved that decreasing the particle size of coatings can increase the transmission depth of radiative heat and get higher emissivity and absorptivity both theoretically and practically. Ultra-attenuation and nanocrystallization will bring a brilliant prospect to the development of radiative coatings.

  17. Stress and structure development in polymeric coatings

    Science.gov (United States)

    Vaessen, Diane Melissa

    2002-09-01

    The main goal of this research is to measure the stress evolution in various polymer coating systems to establish the mechanisms responsible for stress development, stress relaxation, and defect formation. Investigated systems include ultraviolet (UV)-curable coatings, dense and porous coatings from polymer solutions, and latex coatings. Coating stress was measured using a controlled environment stress apparatus based on a cantilever deflection principle. For acrylate coatings, it was found that by cycling a UV-lamp on and off, keeping the total dose constant, coating stress was lowered by 60% by decreasing the cycle period. A stress minimum was also found to exist for a given dose of radiation. The lower stress is attributed to stress relaxation and/or slower reaction during dark periods. A viscoelastic stress model of this process was formulated and predicted stress values close to those observed experimentally. During drying of cellulose acetate (CA) coatings cast in acetone, final stress increased from 10 to 45 MPa as coating thickness decreased from 60 to 10 mum. This thickness dependent coating stress for a solvent-cast polymer coating is a new finding and is attributed to (1) less shrinkage in thicker coatings due to more trapped solvent (from skinning) and (2) greater amounts of polymer stress relaxation in thicker coatings. For porous CA coatings prepared by dry-cast phase separation, final in-plane stresses ranged from 20 MPa for coatings containing small pores (˜1 mum) to 5 MPa for coatings containing small pores and macrovoids (˜200 mum). For these coatings, a small amount of stress relaxation occurs due to capillary pressure relief. A stress plateau for the macrovoid-containing coating is likely caused by stress-induced rupture of the polymer-rich phase. Measured stress in pigment-free latex coatings was much lower (˜0.3 MPa) than UV-curable and solvent-cast polymer coatings and was found to increase with increasing latex glass transition

  18. Evolution of structure and infrared radiation properties for ferrite-based amorphous coating

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Lei [State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081 (China); Fan, Xi’an, E-mail: groupfxa@163.com [State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081 (China); Zhang, Jianyi [State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081 (China); Hu, Xiaoming [Suzhou Sagreon New Materials Co., Ltd, Zhangjiagang 215625 (China); Li, Guangqiang; Zhang, Zhan [State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081 (China)

    2014-10-15

    Highlights: • The ferrite-based amorphous infrared radiation coating was prepared by plasma spraying. • The coating could keep amorphous structure when the temperature was below 700 °C. • The amorphous structure can improve the emissivity of ferrite-based coatings. • The amorphous coating exhibited a higher emissivity than that by brushing process. • The coating has an excellent thermal shock resistance and can work at 1000 °C. - Abstract: The ferrite-based amorphous coatings with high infrared radiation properties have been successfully prepared on the surface of carbon steel substrate by plasma spraying process. The phase, morphology, microstructure, thermal behavior and infrared emissivity were determined by X-ray diffraction, scanning electron microscopy, differential scanning calorimetry and infrared spectroscopy. The prepared coating could keep amorphous structure when the ambient temperature was below 700 °C and it would crystallize gradually with further increasing the temperature. The amorphous structure is confirmed to be constructive for improving the emissivity of ferrite-based coatings, especially in the 3–8 μm band. The emissivity of the amorphous coating obtained by plasma spraying was over 0.8 in 3–8 μm band at 800 °C, which was higher than that of the coating with same composition prepared by conventional brushing method. The excellent thermal shock resistance of the coatings makes them to be good candidates for sensible energy-saving materials, which could work for long term at 1000 °C.

  19. Research on infrared radiation characteristics of Pyromark1200 high-temperature coating

    Science.gov (United States)

    Song, Xuyao; Huan, Kewei; Dong, Wei; Wang, Jinghui; Zang, Yanzhe; Shi, Xiaoguang

    2014-11-01

    Pyromark 1200 (Tempil Co, USA), which is a type of high-temperature high-emissivity coating, is silicon-based with good thermal radiation performance. Its stably working condition is at the temperature range 589~922 K thus a wide range of applications in industrial, scientific research, aviation, aerospace and other fields. Infrared emissivity is one of the most important factors in infrared radiation characteristics. Data on infrared spectral emissivity of Pyromark 1200 is in shortage, as well as the reports on its infrared radiation characteristics affected by its spray painting process, microstructure and thermal process. The results of this research show that: (1) The coating film critical thickness on the metal base is 10μm according to comparison among different types of spray painting process, coating film thickness, microstructure, which would influence the infrared radiation characteristics of Pyromark 1200 coating. The infrared spectral emissivity will attenuate when the coating film thickness is lower or much higher than that. (2) Through measurements, the normal infrared radiation characteristics is analyzed within the range at the temperature range 573~873 K under normal atmospheric conditions, and the total infrared spectral emissivity of Pyromark 1200 coating is higher than 0.93 in the 3~14 μm wavelength range. (3) The result of 72-hour aging test at the temperature 673 K which studied the effect of thermal processes on the infrared radiation characteristics of the coating shows that the infrared spectral emissivity variation range is approximately 0.01 indicating that Pyromark 1200 coating is with good stability. Compared with Nextel Velvet Coating (N-V-C) which is widely used in optics field, Pyromark 1200 high-temperature coating has a higher applicable temperature and is more suitable for spraying on the material surface which is in long-term operation under high temperature work conditions and requires high infrared spectral emissivity.

  20. Application of a Novel Thioxanthone Based Photoinitiator in UV-Curable Waterborne Coating%新型硫杂蒽酮类光引发剂在水性光固化涂料中的应用

    Institute of Scientific and Technical Information of China (English)

    王国建; 卢良

    2012-01-01

    A novel thioxanthone based photoinitiator 2 - Hydroxy -3 - (9-oxo-9H - thioxanth - en -2 - yloxy) - propyl - trimethyl - ammonium chloride ( TX2) was used in the UV - curing of waterborne poly-urethane acrylic ( PUA) coating. The UV - curing process was studied by FT - IR and the gel content analysis. The influence of dry condition, amount of photoinitiator TX2, co - initiator type and dosage on the curing rate was also investigated. The results showed that TX2 had good efficiency for UV - curing of PUA coating. The film of PUA coating should be dried at 90℃ before it was irradiated. In order to obtain better curing rate, Ethyl 4 - dimethylaminobenzoate ( EDAB ) was selected as co - initiator. The optimal amount of TX2 and EDAB were 3. 0% and 2. 0% , respectively. The results of properties test of the cured film showed that hardness was 4H and adhesion grade 1.%采用自行研制的硫杂蒽酮类光引发剂2-羟基-3-(2-硫杂蒽酮氧基)丙基三甲基氯化铵(TX2)引发水性聚氨酯丙烯酸酯(PUA)涂料在紫外光照射条件下固化.分别用FT - IR光谱法和凝胶含最法分析了光固化过程,同时还研究了干燥条件、光引发剂TX2的用量、助引发剂叔胺的类型、叔胺的用量对紫外光固化速度的影响.结果表明:TX2的光固化速度较快,在30 s内基本固化完全;涂料薄膜在光固化前要预先干燥除水,干燥温度为90℃;当TX2的用量为3.0%(质量分数),助引发剂N,N-二甲氨基苯甲酸乙酯(EDAB)的用量为2.0%时,可以得到较快的光同化速度.采用上述工艺和条件得到的固化膜硬度可达4H,附着力可达1级.

  1. Investigation of radiation keeping property of barite coated cloth via image processing method

    Energy Technology Data Exchange (ETDEWEB)

    Kilincarslan, S.; Akkurt, I.; Molla, T.; Akarslan, F. [Department of Construction Education, Suleyman Demirel University, Isparta (Turkey); Department of Physics, Science Faculty, Suleyman Demirel University, Isparta (Turkey); Department of Construction Education, Suleyman Demirel University, Isparta (Turkey); Textil Engineering, Engineering Faculty, Suleyman Demirel University, Isparta (Turkey)

    2012-09-06

    Preservative clothes which are able to absorb radiation beam are needed not only for saving people working at radioactive environment but also for saving others from natural and man-made radiation sources we are exposed in daily life. Barite is a mineral which can be used for armour plating because of high atomic numbered element barium constituent of barite. In this study, armour plating property of barite was applied to fabrics. Barite coated fabric having characteristic of keeping radiation was obtained by penetrating barite on cloth via coating method. Radiation keeping property of fabrics obtained was determined via image processing. The results of experiments showed that barite coated fabrics have blocked radiation more than normal fabrics have done.

  2. On the radiative properties of soot aggregates - Part 2: Effects of coating

    Science.gov (United States)

    Liu, Fengshan; Yon, Jérôme; Bescond, Alexandre

    2016-03-01

    The effects of weakly absorbing material coating on soot have attracted considerable research attention in recent years due to the significant influence of such coating on soot radiative properties and the large differences predicted by different numerical models. Soot aggregates were first numerically generated using the diffusion limited cluster aggregation algorithm to produce fractal aggregates formed by log-normally distributed polydisperse spherical primary particles in point-touch. These aggregates were then processed by adding a certain amount of primary particle overlapping and necking to simulate the soot morphology observed from transmission electron microscopy images. After this process, a layer of WAM coating of different thicknesses was added to these more realistic soot aggregates. The radiative properties of these coated soot aggregates over the spectral range of 266-1064 nm were calculated by the discrete dipole approximation (DDA) using the spectrally dependent refractive index of soot for four aggregates containing Np=1, 20, 51 and 96 primary particles. The considered coating thicknesses range from 0% (no coating) up to 100% coating in terms of the primary particle diameter. Coating enhances both the particle absorption and scattering cross sections, with much stronger enhancement to the scattering one, as well as the asymmetry factor and the single scattering albedo. The absorption enhancement is stronger in the UV than in the visible and the near infrared. The simple corrections to the Rayleigh-Debye-Gans fractal aggregates theory for uncoated soot aggregates are found not working for coated soot aggregates. The core-shell model significantly overestimates the absorption enhancement by coating in the visible and the near infrared compared to the DDA results of the coated soot particle. Treating an externally coated soot aggregate as an aggregate formed by individually coated primary particles significantly underestimates the absorption

  3. Preparation, Characterization and Utilization of Electrodes Coated with Polymeric Networks Formed by Gamma Radiation Crosslinking.

    Science.gov (United States)

    1987-04-01

    CHARACTERIZATION, AND UTILIZATION OF ELECTRODES COATED WITH POLYMERIC NETWORKS FORMED BY GAMMA RADIATION CROSSLINKING FINAL REPORT Accession For NTIS GRA... radiation crosslinking . The polymers and their structures are shown in Table I. All of these have been found to form cross-linked networks when exposed

  4. 低分子聚酰胺650对光固化涂料性能的影响研究%Study on the Influence of Low Molecular Weight Polyamide 650 on the Performance of Light-curable Coatings

    Institute of Scientific and Technical Information of China (English)

    王妮; 邵水源; 宋昌清

    2012-01-01

    Making part of the epoxy groups of E-44 epoxy resin react with acrylic acid, than adding low molecular weight polyamide 650 that has been dissolved in diluents, and stirring them, the light-curable coatings with good flexibility are obtained. This paper discusses the influence of polyamide 650 on the flexibility, hardness and adhesion. With the polyamide 650 amount of 3% (mass fraction), initiated by the composite initiator of BP of 1% and the 184 of 0.5%, it is gotten that the adhesion of film reaches 1 class, the diameter of flexible rod axis is 2ram and the hardness is B. TGA shows that the thermal decomposition transition temperature of cured film is 324 ℃, thermal decomposition temperature of 95% is 335 ℃, and the adding of polyamide 650 has significantly improved the overall performance of the coatings.%以E-44环氧树脂部分环氧基团与丙烯酸反应,加入经稀释剂溶解的低分子聚酰胺650,搅拌制得具有良好柔韧性的光固化涂料,讨论了聚酰胺650用量对涂料柔韧性、硬度及附着力的影响。最终得到:当聚酰胺650用量为3%(质量分数,下同)时,采用1%的二苯甲酮(BP)和0.5%的184复合引发固化,涂膜附着力达到1级,柔韧性棒轴直径为21mm,硬度为B,TGA显示固化涂膜的热分解转折温度为324℃,95%热分解温度为335℃;聚酰胺650的加入明显地改善了涂膜的综合性能。

  5. Radiation Hard Multi-Layer Optical Coatings Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Next-generation space telescopes require advanced optical coatings to provide low-loss polarization-preserving transmission/reflection of light in a variety of...

  6. Radiation Hard Multi-Layer Optical Coatings Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Next generation space telescopes require advanced optical coatings to provide low loss transmission of light in a variety of spectral ranges and protect optical...

  7. Durability and shielding performance of borated Ceramicrete coatings in beta and gamma radiation fields

    Science.gov (United States)

    Wagh, Arun S.; Sayenko, S. Yu.; Dovbnya, A. N.; Shkuropatenko, V. A.; Tarasov, R. V.; Rybka, A. V.; Zakharchenko, A. A.

    2015-07-01

    Ceramicrete™, a chemically bonded phosphate ceramic, was developed for nuclear waste immobilization and nuclear radiation shielding. Ceramicrete products are fabricated by an acid-base reaction between magnesium oxide and mono potassium phosphate. Fillers are used to impart desired properties to the product. Ceramicrete's tailored compositions have resulted in several commercial structural products, including corrosion- and fire-protection coatings. Their borated version, called Borobond™, has been studied for its neutron shielding capabilities and is being used in structures built for storage of nuclear materials. This investigation assesses the durability and shielding performance of borated Ceramicrete coatings when exposed to gamma and beta radiations to predict the composition needed for optimal shielding performance in a realistic nuclear radiation field. Investigations were conducted using experimental data coupled with predictive Monte Carlo computer model. The results show that it is possible to produce products for simultaneous shielding of all three types of nuclear radiations, viz., neutrons, gamma-, and beta-rays. Additionally, because sprayable Ceramicrete coatings exhibit excellent corrosion- and fire-protection characteristics on steel, this research also establishes an opportunity to produce thick coatings to enhance the shielding performance of corrosion and fire protection coatings for use in high radiation environment in nuclear industry.

  8. Durability and shielding performance of borated Ceramicrete coatings in beta and gamma radiation fields

    Energy Technology Data Exchange (ETDEWEB)

    Wagh, Arun S., E-mail: asw@anl.gov [Environmental Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States); Sayenko, S.Yu.; Dovbnya, A.N.; Shkuropatenko, V.A.; Tarasov, R.V.; Rybka, A.V.; Zakharchenko, A.A. [National Science Center, Kharkov Institute of Physics and Technology, Kharkov (Ukraine)

    2015-07-15

    Highlights: • It incorporates all suggestions by the reviewers. • Explanation to each new term is provided and suitable references are given. • Sample identities have been streamlined by revising the text and the tables. • Some figures have been redrawn. - Abstract: Ceramicrete™, a chemically bonded phosphate ceramic, was developed for nuclear waste immobilization and nuclear radiation shielding. Ceramicrete products are fabricated by an acid–base reaction between magnesium oxide and mono potassium phosphate. Fillers are used to impart desired properties to the product. Ceramicrete’s tailored compositions have resulted in several commercial structural products, including corrosion- and fire-protection coatings. Their borated version, called Borobond™, has been studied for its neutron shielding capabilities and is being used in structures built for storage of nuclear materials. This investigation assesses the durability and shielding performance of borated Ceramicrete coatings when exposed to gamma and beta radiations to predict the composition needed for optimal shielding performance in a realistic nuclear radiation field. Investigations were conducted using experimental data coupled with predictive Monte Carlo computer model. The results show that it is possible to produce products for simultaneous shielding of all three types of nuclear radiations, viz., neutrons, gamma-, and beta-rays. Additionally, because sprayable Ceramicrete coatings exhibit excellent corrosion- and fire-protection characteristics on steel, this research also establishes an opportunity to produce thick coatings to enhance the shielding performance of corrosion and fire protection coatings for use in high radiation environment in nuclear industry.

  9. Ultra thin metallic coatings to control near field radiative heat transfer

    Directory of Open Access Journals (Sweden)

    R. Esquivel-Sirvent

    2016-09-01

    Full Text Available We present a theoretical calculation of the changes in the near field radiative heat transfer between two surfaces due to the presence of ultra thin metallic coatings on semiconductors. Depending on the substrates, the radiative heat transfer is modulated by the thickness of the ultra thin film. In particular we consider gold thin films with thicknesses varying from 4 to 20 nm. The ultra-thin film has an insulator-conductor transition close to a critical thickness of dc = 6.4 nm and there is an increase in the near field spectral heat transfer just before the percolation transition. Depending on the substrates (Si or SiC and the thickness of the metallic coatings we show how the near field heat transfer can be increased or decreased as a function of the metallic coating thickness. The calculations are based on available experimental data for the optical properties of ultrathin coatings.

  10. Synthesis of advanced aluminide intermetallic coatings by low-energy Al-ion radiation.

    Science.gov (United States)

    Shen, Mingli; Gu, Yan; Zhao, Panpan; Zhu, Shenglong; Wang, Fuhui

    2016-05-19

    Metals that work at high temperatures (for instance, superalloys in gas-turbines) depend on thermally grown oxide (TGO, commonly alumina) to withstand corrosion attack. Nickel Aluminide (NiAl) as one superior alumina TGO former plays an important role in protective coatings for turbine blades in gas-turbine engines used for aircraft propulsion and power generation. Lowering TGO growth rate is essentially favored for offering sustainable protection, especially in thermal barrier coatings (TBC). However, it can only be achieved currently by a strategy of adding the third element (Pt or reactive elements) into NiAl during traditional diffusion- or deposition-based synthesis of the coating. Here we present a highly flexible Al-ion radiation-based synthesis of advanced NiAl coatings, achieving low TGO growth rate without relying on the third element addition. Our results expand the strategy for lowering TGO growth rate and demonstrate potentials for ion radiation in advancing materials synthesis.

  11. Synthesis of advanced aluminide intermetallic coatings by low-energy Al-ion radiation

    Science.gov (United States)

    Shen, Mingli; Gu, Yan; Zhao, Panpan; Zhu, Shenglong; Wang, Fuhui

    2016-05-01

    Metals that work at high temperatures (for instance, superalloys in gas-turbines) depend on thermally grown oxide (TGO, commonly alumina) to withstand corrosion attack. Nickel Aluminide (NiAl) as one superior alumina TGO former plays an important role in protective coatings for turbine blades in gas-turbine engines used for aircraft propulsion and power generation. Lowering TGO growth rate is essentially favored for offering sustainable protection, especially in thermal barrier coatings (TBC). However, it can only be achieved currently by a strategy of adding the third element (Pt or reactive elements) into NiAl during traditional diffusion- or deposition-based synthesis of the coating. Here we present a highly flexible Al-ion radiation-based synthesis of advanced NiAl coatings, achieving low TGO growth rate without relying on the third element addition. Our results expand the strategy for lowering TGO growth rate and demonstrate potentials for ion radiation in advancing materials synthesis.

  12. Hybrid high refractive index polymer coatings

    Science.gov (United States)

    Wang, Yubao; Flaim, Tony; Mercado, Ramil; Fowler, Shelly; Holmes, Douglas; Planje, Curtis

    2005-04-01

    Thermally curable hybrid high refractive index polymer solutions have been developed. These solutions are stable up to 6 months under room temperature storage conditions and can be easily spin-coated onto a desired substrate. When cured at elevated temperature, the hybrid polymer coating decomposes to form a metal oxide-rich film that has a high refractive index. The resulting films have refractive indices higher than 1.90 in the entire visible region and achieve film thicknesses of 300-900 nm depending on the level of metal oxide loading, cure temperature being used, and number of coatings. The formed films show greater than 90% internal transmission in the visible wavelength (400-700 nm). These hybrid high refractive index films are mechanically robust, are stable upon exposure to both heat and UV radiation, and are currently being investigated for microlithographic patterning potential.

  13. Reverse-tone ultraviolet nanoimprint lithography with fluorescent UV-curable resins

    Science.gov (United States)

    Uehara, Takuya; Kubo, Shoichi; Nakagawa, Masaru

    2015-06-01

    The usefulness of fluorescent ultraviolet (UV)-curable resins for reverse-tone UV nanoimprint lithography was demonstrated. Nanoimprinted concave patterns were fabricated as an underlayer on a Au-deposited substrate using a fluorescent UV-curable resin with a low etching durability after curing. The underlayer was coated with another fluorescent UV-curable resin with a high etching durability after curing. Fluorescence microscopic observation allowed the inspection of the morphological uniformity and thickness of both under and top layers in a nondestructive manner. UV-curing of the top layer in combination with pressing with a flat substrate was necessary for obtaining a flattened top layer surface, which was responsible for allowing the reverse-tone UV nanoimprint lithography. We demonstrated the fabrication of 10-nm-thick Au split-ring resonator structures with a line width of 55 ± 4 nm corresponding to the underlayer concave resist patterns by dry etching during Ar ion milling under the condition that the etching rate ratio of the underlayer to the top layer was 6.

  14. Radiation-Resistant Hybrid Lotus Effect for Achieving Photoelectrocatalytic Self-Cleaning Anticontamination Coatings

    Science.gov (United States)

    Taylor, Edward W.; Pirich, Ronald G.

    2011-01-01

    An experiment involving radiation-resistant hydrophobic coatings is planned for space exposure and experimental testing on the International Space Station (ISS) in 2011. The Lotus biocide coatings are designed for supporting space exploration missions. This innovation is an antibacterial, anti-contamination, and self-cleaning coating that uses nano-sized semiconductor semimetal oxides to neutralize biological pathogens and toxic chemicals, as well as to mitigate dust accumulation (see figure). The Lotus biocide coating is thin (approximately microns thick), lightweight, and the biocide properties will not degrade with time or exposure to biological or chemical agents. The biocide is stimulated chemically (stoichiometric reaction) through exposure to light (photocatalysis), or by an applied electric field (electrocatalysis). The hydrophobic coating samples underwent preliminary high-energy proton and alpha-ray (helium ion) irradiations at the Lawrence Berkeley National Laboratory 88" cyclotron and demonstrated excellent radiation resistance for a portion of the Galactic Cosmic Ray (GRC) and Solar Proton spectrum. The samples will undergo additional post-flight studies when returned to Earth to affirm further the radiation resistance properties of the space exposed coatings.

  15. Size-dependent radiosensitization of PEG-coated gold nanoparticles for cancer radiation therapy

    CERN Document Server

    Zhang, Xiao-Dong; Shen, Xiu; Chen, Jie; Sun, Yuan-Ming; Liu, Pei-Xun; Liang, Xing-Jie

    2012-01-01

    Gold nanoparticles have been conceived as a radiosensitizer in cancer radiation therapy, but one of the important questions for primary drug screening is what size of gold nanoparticles can optimally enhance radiation effects. Herein, we perform in vitro and in vivo radiosensitization studies of 4.8, 12.1, 27.3, and 46.6 nm PEG-coated gold nanoparticles. In vitro results show that all sizes of the PEG-coated gold nanoparticles can cause a significant decrease in cancer cell survival after gamma radiation. 12.1 and 27.3 nm PEG-coated gold nanoparticles have dispersive distributions in the cells and have stronger sensitization effects than 4.8 and 46.6 nm particles by both cell apoptosis and necrosis. Further, in vivo results also show all sizes of the PEG-coated gold nanoparticles can decrease tumor volume and weight after 5 Gy radiations, and 12.1 and 27.3 nm PEG-coated gold nanoparticles have greater sensitization effects than 4.8 and 46.6 nm particles, which can lead to almost complete disappearance of the ...

  16. Reduction in emittance of thermal radiator coatings caused by the accumulation of a Martian dust simulant

    Energy Technology Data Exchange (ETDEWEB)

    Hollingsworth, D. Keith; Witte, Larry C.; Hinke, Jaime [Department of Mechanical Engineering, University of Houston, Houston, TX 77204-4006 (United States); Hurlbert, Kathryn [NASA, Johnson Space Center (United States)

    2006-12-15

    Measurements were made of the effective emittance of three types of radiator coatings as a Martian dust simulant was added to the radiator surfaces. The apparatus consisted of multiple radiator coupons on which Carbondale Red Clay dust was deposited. The coupon design employed guard heating to achieve the accuracy required for acceptable emittance calculations. The apparatus was contained in a vacuum chamber that featured a liquid-nitrogen cooled shroud that simulated the Martian sky temperature. Three high-emittance radiator coatings were tested: two while silicate paints, Z-93P and NS-43G, and a silver Teflon film. Radiator temperatures ranged from 250 to 350K with sky temperatures from 185 to 248K. As dust was added to the radiator surfaces, the effective emittance of all three coatings decreased from initial values near 0.9 to a value near 0.4. A low-emittance control surface, polished aluminum, demonstrated a rise in effective emittance for thin dust layers, and then a decline as the dust layer thickened. This behavior is attributed to the conductive resistance caused by the dust layer. (author)

  17. Curing Behavior and Viscoelasticity of Dual-Curable Adhesives Based on High-Reactivity Azo Initiator

    Science.gov (United States)

    Lee, Jong-Gyu; Shim, Gyu-Seong; Park, Ji-Won; Kim, Hyun-Joong; Moon, Sang-Eun; Kim, Young-Kwan; No, Dong-Hun; Kim, Jong-Hwan; Han, Kwan-Young

    2016-07-01

    We have investigated the curing behavior of dual-curable acrylic resin to solve problems associated with curing of adhesives in shaded areas during display manufacture. A low-temperature curing-type thermal initiator, 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), with a 30°C half-life decomposition temperature was used in the investigation. Dual-curable adhesives were prepared according to the thermal initiator content and ultraviolet (UV) radiation dose. The effects of thermal initiator and UV irradiation on the curing behavior and viscoelasticity were investigated. Using Fourier-transform infrared spectroscopy and gel-fraction analysis, an evaluation was carried out to determine the degree of curing after dual UV/thermal curing. In addition, the real-time curing behavior was evaluated using thermogravimetric analysis, differential scanning calorimetry, and a UV/advanced rheometric expansion system. A lift-off test was carried out to verify the effects of dual curing on adhesion performance. Application of UV irradiation before thermal curing suppressed the thermal curing efficiency. Also, the network structure formed after dual curing with low UV dose showed higher crosslinking density. Therefore, the thermal initiator radical effectively influenced uncured areas with low curing temperature and initiator content without causing problems in UV-curable zones.

  18. Wakefield radiation from the open end of an internally coated metallic tube

    Directory of Open Access Journals (Sweden)

    M. Ivanyan

    2014-07-01

    Full Text Available In this paper the problem of radiation from the open end of a semi-infinite circular metallic waveguide with perfectly conducting walls and a thin internal low-conducting metal coating is considered. Electromagnetic fields are generated by the ultrarelativistic point charge moving along the axis of the waveguide. The far fields of radiation are obtained using the near-field to far-field recovery technique. The technique is extended for the nonmonochromatic waves. It is shown that the radiation has a narrow-band and narrow-directional character.

  19. Improved postharvest quality in patagonian squash (Cucurbita moschata) coated with radiation depolymerized chitosan

    Energy Technology Data Exchange (ETDEWEB)

    Pugliese, Maria Alicia; Goitia, Maria Teresa [Laboratorio de Investigaciones Basicas Aplicadas en Quitina, Departamento de Quimica, Universidad Nacional del Sur. Avenida Alem 1253, B8000CPB Bahia Blanca (Argentina); Yossen, Mariana [Instituto de Desarrollo Tecnologico para la Industria Quimica (INTEC), CONICET-Universidad Nacional del Litoral, Ruta Nacional 168-Paraje ' El Pozo' , 3000 Santa Fe (Argentina); Cifone, Norma; Agullo, Enrique [Laboratorio de Investigaciones Basicas Aplicadas en Quitina, Departamento de Quimica, Universidad Nacional del Sur. Avenida Alem 1253, B8000CPB Bahia Blanca (Argentina); Andreucetti, Noemi, E-mail: andreuce@criba.edu.ar [Laboratorio de Radioisotopos, Departamento de Quimica, Universidad Nacional del Sur, Avenida Alem 1253, B8000CPB Bahia Blanca (Argentina)

    2011-12-15

    Different molecular weight chitosans were evaluated on the decay of coated Anquito squashes (Cucurbita moschata) as well as the maintenance of the fruit quality along five storage months. The original chitosan (Mw=391 kDa, 83% DD), was depolymerized by gamma radiation. Apart from chain scission, other chemical changes were not detected by FTIR or UV-vis analyses. The molecular weight characterization of chitosans was done by size exclusion chromatography with dual light scattering and concentration detection (SEC-MALLS-RI). The coating effectiveness was evaluated on the following parameters: fungal decay incidence, weight loss, firmness, total reducing sugar, soluble solid, flesh color, carotene content, pH and titratable acidity. No sign of fungal decay was observed in squashes coated with 122 and 56 kDa chitosans, which were also the most effective treatments in reducing the weight loss. The chitosan with Mw=122 kDa was also the best treatment considering firmness, internal aspect, sugar and carotene content. Then, radiation degraded chitosan was better in C. moschata preservation than the original chitosan. - Highlights: > Original Chitosan was radiation depolymerized producing chitosans with lower molecular weights. > Gamma-irradiated chitosans only exhibit chain scission. > SEC-MALLS-RI chromatography is a useful tool in molecular weight analysis. > Depolymerized chitosans were the best in maintaining the quality and the storage life of coated squashes.

  20. Coatings manufactured using magnetron sputtering technology to protect against infrared radiation for use in firefighter helmets

    Directory of Open Access Journals (Sweden)

    Fejdyś Marzena

    2016-09-01

    Full Text Available The aim of this study was to test the usefulness of magnetron sputtering technology to produce coatings on selected elements of a firefighter’s helmet to protect against infrared radiation (PN-EN 171 standard. The scope of research includes testing the deposition produced via magnetron sputtering of metallic and ceramic coatings on plastics, which are used to manufacture the components comprising the personal protection equipment used by firefighters. The UV-VIS, NIR used to research the permeation coefficients and reflections for light and infrared light and the emission spectrometry with ICP-AES used for the quantitative analysis of elements in metallic and ceramic coatings. Microstructural and micro-analytical testing of the coatings were performed using scanning electron microscopy (SEM. Measurements of the chemical compositions were conducted using energy-dispersive X-ray spectroscopy (EDS. The hardnesss of the coatings were tested using a indentation method, and the coating thicknesses were tested using a ellipsometry method.

  1. The spectral emittance and stability of coatings and textured surfaces for thermophotovoltaic (TPV) radiator applications

    Energy Technology Data Exchange (ETDEWEB)

    Cockeram, B.V.; Hollenbeck, J.L.

    2000-11-01

    Coatings or surface modifications are needed to improve the surface emissivity of materials under consideration for TPV radiator applications to a value of 0.8 or higher. Vacuum plasma spray coatings (ZrO{sub 2} + 18% TiO{sub 2} + 10% Y{sub 2}O{sub 3}, ZrC, Fe{sub 2}TiO{sub 5}, ZrTiO{sub 4}, ZrO{sub 2} + 8% Y{sub 2}O{sub 3} + 2% HfO{sub 2}, and Al{sub 2}O{sub 3} + TiO{sub 2}) and a chemical vapor deposited coating of rhenium whiskers were used to increase the surface emissivity of refractory metal and nickel-base materials. Emittance measurements following 4000 hours of vacuum annealing at 1100 C show that only the ZrO{sub 2} + 18% TiO{sub 2} + 10% Y{sub 2}O{sub 3}, ZrC, and Al{sub 2}O{sub 3} + TiO{sub 2} coatings have the desired thermal stability, and maintain emissivity values higher than 0.8. These coatings are graybody emitters, and provide a high emissivity value in the wavelength range that is relevant to the TPV cells. The highest emissivity values were observed for the Al{sub 2}O{sub 3} + TiO{sub 2} coatings, with post-anneal values higher than graphite.

  2. Coatings of metal substrates assisted by laser radiation

    Directory of Open Access Journals (Sweden)

    Caudevilla, H.

    1998-04-01

    Full Text Available In this contribution, a new way of obtaining ceramic coatings is presented. This method uses precursor suspensions, settled on substrates and in-situ pyrolised with a laser. Different deposition techniques of the ceramic precursors have been tested in order to obtain a homogeneous distribution on the metal substrate before the laser treatment.

    La combinación de recubrimientos utilizando disoluciones de precursores metálicos con la pirólisis asistida por láser, permite obtener una gran diversidad de recubrimientos sobre sustratos de muy distinta naturaleza. Se han realizado estudios, tanto con disoluciones poliméricas, como con disoluciones de tipo sol-gel y pastas obtenidas con técnicas similares, depositadas utilizando métodos convencionales de inmersión y atomización previa a la pirólisis asistida por láser, así como simultánea. En este trabajo se presenta un resumen de los resultados más significativos obtenidos en la realización de recubrimientos sobre sustratos metálicos y cerámicos.

  3. Effect of radiation and temperature on resonance properties of polyurethane-coated wire bonds

    Science.gov (United States)

    Izen, J. M.; Chen, Y.; Kurth, M.

    2017-04-01

    Thin polyurethane (PU) coatings for aluminum wedge wire bonds are proposed to protect the ATLAS Inner Tracker upgrade from oscillations from periodic Lorentz forces and condensation-induced corrosion. Coating robustness after exposure to lifetime doses expected by parts of a tracking detector at the High Luminosity-Large Hadron Collider has been evaluated. Mechanical properties of irradiated samples were tested at room temperature and at 0-2° C. Irradiated samples were thermal-cycled to test for radiation-induced intolerance to thermal expansion. Mechanical vibrations of PU-coated wire bonds (99% aluminum, 1% silicon, 25 μ m diameter) were excited with 50% duty-cycle square wave currents in a 1.0 T field. The most vulnerable endcap disk geometry (magnetic field perpendicular to the wire bond and parallel to the normal of its PC board) was used. Resonance characteristics have been measured up to anticipated lifetime doses.

  4. Shuttle active thermal control system development testing. Volume 7: Improved radiator coating adhesive tests

    Science.gov (United States)

    Reed, M. W.

    1973-01-01

    Silver/Teflon thermal control coatings have been tested on a modular radiator system projected for use on the space shuttle. Seven candidate adhesives have been evaluated in a thermal vacuum test on radiator panels similar to the anticipated flight hardware configuration. Several classes of adhesives based on polyester, silicone, and urethane resin systems were tested. These included contact adhesives, heat cured adhesives, heat and pressure cured adhesives, pressure sensitive adhesives, and two part paint on or spray on adhesives. The coatings attached with four of the adhesives, two silicones and two urethanes, had no changes develop during the thermal vacuum test. The two silicone adhesives, both of which were applied to the silver/Teflon as transfer laminates to form a tape, offered the most promise based on application process and thermal performance. Each of the successful silicone adhesives required a heat and pressure cure to adhere during the cryogenic temperature excursion of the thermal-vacuum test.

  5. Graphene coated subwavelength wires: a theoretical investigation of emission and radiation properties

    Science.gov (United States)

    Cuevas, Mauro

    2017-10-01

    This work analyzes the emission and radiation properties of a single optical emitter embedded in a graphene-coated subwavelength wire. We discuss the modifications of the spontaneous emission rate and the radiation efficiency as a function of the position and orientation of the dipole inside the wire. Our results show that these quantities can be enhanced by several orders of magnitude when the emission frequency coincides with one of the resonance frequencies of the graphene-coated wire. In particular, high-order plasmon resonances are excited when the emitter is moved from the wire center. Modifications resulting from varying the orientation of the dipole in the near field distribution and in the far field intensities are shown.

  6. Effects of Vacuum Ultraviolet Radiation on Atomic Oxygen Erosion of Polysiloxane/SiO2 Hybrid Coatings

    Institute of Scientific and Technical Information of China (English)

    Longfei Hu; Meishuan Li; Yanchun Zhou

    2009-01-01

    Polysiloxane/SiO2 hybrid coatings have been prepared on Kapton films by a sol-gel process. The erosion resistance of polysiloxane/SiO2 (20 wt pct) coating was evaluated by exposure tests of vacuum ultraviolet radiation (VUV) and atomic oxygen beam (AO) in a ground-based simulation facility. The experimental results indicate that this coating exhibits better AO resistance than pure polysiloxane coating. The erosion yield (Ey) of the polysiloxane/SiO2 (20 wt pct) hybrid coating is about 10-27 cm3/atom, being one or two orders of magnitude lower than that of polysiloxane. VUV radiation can affect the erosion process greatly. Under simultaneous AO and VUV exposure, the value of Ey of the polysiloxane/SiO2 (20 wt pct) hybrid coating increases by 39% compared with that under single AO exposure.

  7. Near-Field Radiative Heat Transfer between Metamaterials coated with Silicon Carbide Film

    OpenAIRE

    Basu, Soumyadipta; YANG, YUE; Wang, Liping

    2014-01-01

    In this letter, we study the near-field radiative heat transfer between two metamaterial substrates coated with silicon carbide (SiC) thin films. It is known that metamaterials can enhance the near-field heat transfer over ordinary materials due to excitation of magnetic plasmons associated with s polarization, while strong surface phonon polariton exists for SiC.By careful tuning of the optical properties of metamaterial it is possible to excite electrical and magnetic resonance for the meta...

  8. Investigation of the effects of tumor size and type of radionuclide on tumor curability in targeted radiotherapy

    Directory of Open Access Journals (Sweden)

    Hassan Ranjbar

    2015-07-01

    Full Text Available Background: Targeted radiotherapy is one of the important methods of radiotherapy that involves the use of beta-emitting radionuclides to deliver a dose of radiation to tumor cells. An important feature of this method is the tumor size and the finite range of beta particles emitted as a result of radionuclide disintegration those have significant effects for the curability of tumors. Material and Methods: Monte Carlo simulations and mathematical models have been used to investigate the relationship of curability to tumors size for tumors treated with targeted 131I and 90Y. The model assumed that radionuclides are distributed uniformly throughout tumors. Results: The results show that there is an optimal tumor size for cure. For any given cumulated activity, cure probability is greatest for tumors whose diameter is close to the optimum value. There is a maximum value of curability that occurs at a diameter of approximately 3.5 mm for 131I. For 90Y maximum curability occurs at a tumor diameter of approximately 3.5 cm. Tumors smaller than the optimal size are less vulnerable to irradiation from radionuclides because a significant proportion of the disintegration energy escapes and is deposited outside the tumor volume. Tumors larger than the optimal size are less curable because of greater clonogenic cell number. Conclusion: With single radionuclide targeted radiotherapy, there is an optimal tumor size for tumor cure. It is suggested that single agent targeted radiotherapy should not be used for treatment of disseminated disease when multiple tumors of differing size may be present. The use of several radionuclides concurrently would be more effective than reliance on single radionuclide. This approach of using combination of radionuclides with complementary properties could hopefully prepare new measures and improve the efficiency of tumor therapy.

  9. Measurements of internal stresses in bond coating using high energy x-rays from synchrotron radiation source

    CERN Document Server

    Suzuki, K; Akiniwa, Y; Nishio, K; Kawamura, M; Okado, H

    2002-01-01

    Thermal barrier coating (TBC) techniques enable high temperature combustion of turbines made of Ni-base alloy. TBC is made of zirconia top coating on NiCoCrAlY bond coating. The internal stresses in the bond coating play essential role in the delamination or fracture of TBC in service. With the X-rays from laboratory equipments, it is impossible to measure nondestructively the internal stress in the bond coating under the top coating. synchrotron radiations with a high energy and high brightness have a large penetration depth as compared with laboratory X-rays. Using the high energy X-rays from the synchrotron radiation, it is possible to measure the internal stress in the bond coating through the top coating. In this study, the furnace, which can heat a specimen to 1473 K, was developed for the stress measurement of the thermal barrier coatings. The internal stresses in the bond coating were measured at the room temperature, 773 K, 1073 K and 1373 K by using the 311 diffraction from Ni sub 3 Al with about 73...

  10. Development of Radiation Curable polymeric Gel Electrolyte Formulation

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jin Hoo; Kim, Hyun Kyung; Shin, Choon Hee; Han, Chang Ho; Kim, Ki Ho [Chosun University, Gwangju (Korea, Republic of)

    2010-06-15

    The result of this study, the free lithium ions of polymer gel electrolyte containing hydroxyproply Cellulose 1% is the most excellent due to irradiate of strong energy over quick time, although curing reaction of EB system is a very fast, polymer gel electrolyte containing hydroxypropyl Cellulose Fabricated by UV system is excellent curing reaction and ionic conductivity and mechanical properties and thermal stability than EB system

  11. Improved postharvest quality in patagonian squash ( Cucurbita moschata) coated with radiation depolymerized chitosan

    Science.gov (United States)

    Pugliese, Maria Alicia; Goitia, Maria Teresa; Yossen, Mariana; Cifone, Norma; Agulló, Enrique; Andreucetti, Noemi

    2011-12-01

    Different molecular weight chitosans were evaluated on the decay of coated Anquito squashes ( Cucurbita moschata) as well as the maintenance of the fruit quality along five storage months. The original chitosan (Mw=391 kDa, 83% DD), was depolymerized by gamma radiation. Apart from chain scission, other chemical changes were not detected by FTIR or UV-vis analyses. The molecular weight characterization of chitosans was done by size exclusion chromatography with dual light scattering and concentration detection (SEC-MALLS-RI). The coating effectiveness was evaluated on the following parameters: fungal decay incidence, weight loss, firmness, total reducing sugar, soluble solid, flesh color, carotene content, pH and titratable acidity. No sign of fungal decay was observed in squashes coated with 122 and 56 kDa chitosans, which were also the most effective treatments in reducing the weight loss. The chitosan with Mw=122 kDa was also the best treatment considering firmness, internal aspect, sugar and carotene content. Then, radiation degraded chitosan was better in C. moschata preservation than the original chitosan.

  12. Synthesis and application of novel EB curable polyester urethane acrylate modified by linseed oil fatty acid

    Science.gov (United States)

    Jun, Li; Xuecheng, Ju; Min, Yi; Jinshan, Wei; Hongfei, Ha

    1999-06-01

    A novel polyester urethane acrylate resin modified by linseed oil fatty acid (LFA) was synthesized and EB curing coating was formulated in this work. When the coating cured by EB radiation on the timber, the cured coating was possessed of good performances.

  13. Near-Field Radiative Heat Transfer between Metamaterials coated with Silicon Carbide Film

    CERN Document Server

    Basu, Soumyadipta; Wang, Liping

    2014-01-01

    In this letter, we study the near-field radiative heat transfer between two metamaterial substrates coated with silicon carbide (SiC) thin films. It is known that metamaterials can enhance the near-field heat transfer over ordinary materials due to excitation of magnetic plasmons associated with s polarization, while strong surface phonon polariton exists for SiC.By careful tuning of the optical properties of metamaterial it is possible to excite electrical and magnetic resonance for the metamaterial and surface phonon polaritons for SiC at different spectral regions, resulting in the enhanced heat transfer. The effect of the SiC film thickness at different vacuum gaps is investigated. Results obtained from this study will be beneficial for application of thin film coatings for energy harvesting.

  14. Radiative rate modification in CdSe quantum dot-coated microcavity

    Energy Technology Data Exchange (ETDEWEB)

    Veluthandath, Aneesh V.; Bisht, Prem B., E-mail: bisht@iitm.ac.in [Department of Physics, Indian Institute of Technology Madras, Chennai 600036 (India)

    2015-12-21

    Whispering gallery modes (WGMs) of the microparticles with spherical or cylindrical symmetry have exceptionally high quality factors and small mode volume. Quantum dots (QDs) are zero dimensional systems with variable band gap as well as luminescent properties with applications in photonics. In this paper, the WGMs have been observed in the luminescence spectra of CdSe QD-coated single silica microspheres. Theoretical estimations of variation of resonance frequency, electric field, and Q-values have been done for a multilayer coating of QDs on silica microspheres. Observed WGMs have been identified for their mode number and polarization using Mie theory. Broadening of modes due to material absorption has been observed. Splitting of WGMs has also been observed due to coherent coupling of counter propagating waves in the microcavity due to the presence of QDs. At room temperature, the time-resolved study indicates the modification of the radiative rate due to coupling of WGMs of the microcavity-QD hybrid system.

  15. Hollow polycarbonate waveguides with inner Cu coatings for delivery of terahertz radiation.

    Science.gov (United States)

    Harrington, James; George, Roshan; Pedersen, Pal; Mueller, Eric

    2004-10-18

    Terahertz (THz) radiation has important applications in spectroscopy, imaging, and space science. Fiber optics for the THz region have been limited to rigid hollow metallic waveguides or short lengths of solid-core transparent dielectrics such as sapphire and plastic. We have fabricated flexible, hollow polycarbonate waveguides with interior Cu coatings for broadband THz transmission using simple liquid-phase chemistry techniques. The losses for these hollow-core guides were measured using a tunable, cw single-mode far IR laser. The losses for the best guides were found to be less than four dB/m and the single mode of the laser was preserved for the smaller bore waveguides.

  16. Construction tolerances for low loss, dielectric coated, metallic waveguide for transmission optical radiation

    Energy Technology Data Exchange (ETDEWEB)

    Sandweiss, J.

    1984-08-01

    The transmission of radiation, in a specific mode of interest for the IFELA, past a symmetric step in dielectric coating thickness has been calculated. The result shows that the transmission loss depends on the quantity (s/D)/sup 2/ and vanishes to first order in the ratio of the step s to the guide aperture D. With the reasonable assumption that this feature holds for all forms of surface imperfections, the attenuation length due to imperfections has been estimated. It is found that rms surface roughness of approx. 0.1 ..mu.. m leads to attenuation lengths of 25 km or greater.

  17. Analysis of characteristics of sound radiation from double cylindrical shell coated with viscoelastic layer

    Institute of Scientific and Technical Information of China (English)

    CHEN Meixia; LUO Dongping; PENG Xu; LUO Bin

    2004-01-01

    The characteristics of vibration and sound radiation from a double shell with the outer shell coated with viscoelastic layer are systematically studied. The shell's motion funcby three-dimensional Navier equations, whose displacement solutions are expressed by Taylor expansion along the layer thickness. The continuity conditions of displacement and stress between the shell and the layers are used in obtaining the vibration equations. The effects of layer thickness, modulus of elasticity, the loss factor, and the hydro-compressibility on the structural acoustic characteristic are discussed in detail. It showed that the higher the modulus of elasticity is, or the thinner the thickness of layer is, or the smaller the loss factor is, the higher the sound radiation power is.

  18. Study of mass loss of spacecraft polymeric thermal control coatings under electron and proton radiations

    Science.gov (United States)

    Khasanshin, Rashid; Novikov, Lev; Galygin, Alexander

    Polymeric composites have a number of properties that give a possibility to apply them as spacecraft external coatings. In space environment, however, such materials become one of the main sources of volatile products that form the outer spacecraft atmosphere and are able to con-dense on contamination-sensitive surfaces of onboard equipment. Thermal control coatings oc-cupy a considerable part of a satellite surface and are mostly subjected to ionizing radiations ac-companying by outgassing. The main stages of the process are the following: formation of vola-tile radiolysis products, diffusion of the products to free material surface, and desorption. Radia-tion-induced destruction and outgassing of material increase its permeability and accelerate mi-gration processes in it. Experimental data of effect of radiation on mass loss of polymeric composites used as thermal control coatings was analyzed and interpreted in the work. As a particular case, it was shown that mass loss of a polymeric composite irradiated by protons is greater than by electrons if energies and flux densities of the particles are the same. It can be explained that volatile products, in the first case, generate within a thin near-surface layer of material which permeability increases together with the absorbed dose, and quickly escape in vacuum. In the second case, a bulk of volatile products emerges far enough from the free surface of material which permeability increases slower as compared with proton radiation. Therefore, migration time of volatile products to the free surface grows and quantity of chemical reactions which they are involved in increases. To analyze and interpret experimental data, a mathematical model describing mass loss of polymeric composites subject to its growth of permeability under radiation is proposed. Based upon analysis of experiments and numerical simulation results, thresholds of fluen-cies and flux densities of electron and proton were determined. Exceeding these

  19. Preparation, Microstructure and Properties of NiO-Cr_2O_3-TiO_2 Infrared Radiation Coating

    Institute of Scientific and Technical Information of China (English)

    Wu Chen; Weiping Ye; Xudong Cheng; Wei Duan; Fang Mao; Deliang Li

    2009-01-01

    The spherical agglomerated particles were fabricated by spray drying with the powders of NiO, Cr_2O_3 and TiO2. Plasma spray power, which has good property of flowability, was acquired by heat treatment from the particles at 1200℃ in the reducing atmosphere. Dark and uniform coating of More than 50 μm thick was deposited on the copper sheet substrate by plasma spraying. It is found that the infrared normal total emissivity of the coating is up to 0.91 at 600℃ by infrared radiation testing. The X-ray diffraction analysis shows that the formation of (Cr_0.88Ti_0.12)_2O_3 and spinel structural NiCr_2O_4 in the coating is the main reason for high efficient infrared radiation, and the phase structure and performance of coating is favorable under the thermal cycle between room temperature and 600℃.

  20. Effects of ultraviolet and protons radiations on thermal control coatings after contamination

    Science.gov (United States)

    Faye, D.; Marco, J.

    2003-09-01

    The impact of molecular deposits from spacecraft materials outgassing is not only dependent on sensitive surface nature and contaminant type but also on space environment parameters. In order to study the combined effects of contamination and solar radiation, ground tests have been performed on thermal control coatings: innovative ones such as Flexible and Rigid Solar Reflectors (FSR and RSR), and classic ones such as Optical Solar Reflectors (OSR) and Second Surface Mirrors (SSM). During a first phase, samples of these cold coatings have been exposed to an outgassing flux of different widely used materials: - a PU1 black paint, - a conformal coating MAPSIL 213B, - a structural adhesive Scotchweld EC2216 and to an outgassing flux coming from the mixture of these three materials. During a second phase, the samples have been exposed through two successive tests (either under UV or protons) to a simulated space environment corresponding to one year satellite GEO orbit on North / South faces. Material degradation has been evaluated by in-situ reflectance spectra in the range 250-2500 nm (UV test) and in the range 250-840 nm (Protons test). Negligible changes occurred during initial air to vacuum transition whereas significant recoveries of degradations occurred when returning to ambient atmospheric pressure. The observed degradation is the most important in the UV-visible range independently of the contaminants and substrates. It is partly due to contaminants and substrates for silicone cold coatings FSRs, RSRs, mainly due to contaminants for OSRs, SSMs and mainly due to substrates in the case of paints.

  1. Separation of water and oil by poly (acrylic acid)-coated stainless steel mesh prepared by radiation crosslinking

    Energy Technology Data Exchange (ETDEWEB)

    Nho, Young Chang; Shin, Jung Woong; Park, Jong Seok; Lim, Young Mook; Jeun, Joon Pyo; Kang, Phil Hyun [Research Division for Industry and Environment, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2015-05-15

    The stainless steel mesh coated with poly(acrylic acid) hydrogel was fabricated and applied for the separation of water and oil. The stainless steel mesh was immersed in aqueous poly (acrylic acid) solution, and then irradiated by radiation to introduce poly(acrylic acid) hydrogel on the surface of mesh by crosslinking. It was possible to separate oil and water from mixtures of oil/water effectively using the hydrogel-coated mesh. The effect of irradiation dose, coating thickness, size of mesh on the separation efficiency was examined.

  2. Ferrites based infrared radiation coatings with high emissivity and high thermal shock resistance and their application on energy-saving kettle

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jianyi [The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, 947 Heping Road, Qingshan District, Wuhan 430081 (China); Fan, Xi’an, E-mail: groupfxa@163.com [The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, 947 Heping Road, Qingshan District, Wuhan 430081 (China); Lu, Lei [The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, 947 Heping Road, Qingshan District, Wuhan 430081 (China); Hu, Xiaoming [Suzhou Sagreon New Materials Co., Ltd, Zhangjiagang 215625 (China); Li, Guangqiang [The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, 947 Heping Road, Qingshan District, Wuhan 430081 (China)

    2015-07-30

    Highlights: • The ferrites based infrared radiation coating was prepared by HVOF for the first time. • The infrared radiation coatings were applied firstly on the household kettle. • The bonding strength between the coating and substrate could reach 30.7 MPa. • The coating kept intact when cycle reached 27 by quenching from 1000 °C using water. • The energy-saving efficiency of the kettle with coating could reach 30.5%. - Abstract: Starting from Fe{sub 2}O{sub 3}, MnO{sub 2}, Co{sub 2}O{sub 3} and NiO powders, the ferrites based infrared radiation coatings with high emissivity and high thermal shock resistance were successfully prepared on the surface of carbon steel by high velocity oxy-fuel spraying (HVOF). The coating thickness was about 120–150 μm and presented a typical flat lamellar structure. The coating surface was rough and some submicron grade grains distributed on it. The infrared emissivity of the ferrites based coating by HVOF was over 0.74 in 3–20 μm waveband at 800 °C, which was obviously higher than that of the coating by brushing process in the short waveband. The bonding strength was 30.7 MPa between the coating and substrate, which was five times more than that of conventional coatings by brushing process. The combined effect of the superior bonding strength, typical lamellar structure, pre-existing microcracks and newly generated pores made the cycle times reach 27 when the coating samples were quenched from 1000 °C using water. Lastly, the infrared radiation coatings were applied on the underside of household kettle, and the energy-saving efficiency could reach 30.5%. The ferrites based infrared radiation coatings obtained in this work are good candidates for saving energy in the field of cookware and industrial high temperature furnace.

  3. Analysis of sublimation-cooled coated mirrors in convective and radiative environments.

    Science.gov (United States)

    Howe, J. T.; Green, M. J.

    1973-01-01

    Analytical solutions were obtained for the thermal response of a transpiration- or sublimation-cooled spherical mirror coating exposed to convective and radiative heating. The solutions allow unlimited spectral detail to be accounted for. Results indicate that transpiration-cooled thick coatings (1 cm) may withstand up to 10 kW/sq cm on a steady basis without excessive temperature rise for quartzlike materials with an internal absorption coefficient of 0.01 per cm. On a transient basis, fluxes up to 20 kW/sq cm can be accommodated for a second (cW laser exposure time), 4 kW/sq cm for 5 sec (planetary entry heating time), and of the order of MW/sq cm for millisecond times (short-duration laser bursts) without transpiration cooling for a material with an absorption coefficient of 0.1 per cm. Proportionately higher fluxes can be accommodated with lower absorption coefficients. Thermal stresses produced by the heat pulse are found to be high but within the strength of the materials. The regime in which meaningful solutions may be obtained is mapped in detail.

  4. THE INVESTIGATION OF INFLUENCE OF LASER RADIATION ON THE STRUCTURE AND MECHANICAL PROPERTIES OF COMPOSITE ELECTROLYTIC NICKEL COATING

    Directory of Open Access Journals (Sweden)

    V. A. Zabludovsky

    2013-09-01

    Full Text Available Purpose. Investigation of laser radiation effect on the structure and mechanical properties of electrodeposited nickel composite coatings containing ultrafine diamonds. Methodology. Electrodeposition of nickel films was carried out with the addition of a standard solution of ultrafine diamonds (UFD on laser-electrolytic installation, built on the basis of the gas-discharge CO2 laser. Mechanical testing the durability of coatings were performed on a machine with reciprocating samples in conditions of dry friction against steel. The spectral microanalysis of the elemental composition of the film - substrate was performed on REMMA-102-02. Findings. Research of nickel coatings and modified ultrafine diamond electrodeposited under external stimulation laser demonstrated the dependence of the structure and mechanical properties of composite electrolytic coating (CEC, and the qualitative and quantitative distribution of nanodiamond coprecipitated from an electrodeposition method. Originality. The effect of laser light on the process of co-precipitation of the UFD, which increases the micro-hardness and wear resistance of electrolytic nickel coatings was determined. Practical value. The test method of laser-stimulated composite electrolytic nickel electrodeposition coating is an effective method of local increase in wear resistance of metal coatings, which provides durability save performance (functional properties of the surface.

  5. Discharge of viscous UV-curable resin droplets by screen printing for UV nanoimprint lithography

    Science.gov (United States)

    Tanabe, Akira; Uehara, Takuya; Nagase, Kazuro; Ikedo, Hiroaki; Hiroshiba, Nobuya; Nakamura, Takahiro; Nakagawa, Masaru

    2016-06-01

    We demonstrated a coating method of screen printing for discharging droplets of a high-viscosity resin on a substrate for ultraviolet (UV) nanoimprint lithography (NIL). Compared with a spin-coated resin film on a silicon substrate, discharged resin droplets on a silicon substrate were effective in terms of the uniformity of residual layer thickness (RLT) in contact with a mold with various pattern densities. Fluorescence microscope observations with a fluorescent-dye-containing UV-curable resin enabled the evaluation of the shapes of resin droplets discharged on a substrate surface. Widely used screen mesh plates composed of a stainless mesh covered with a patterned emulsion film caused defects of undischarged parts, whereas defects-free resin droplets with a narrow size distribution were discharged by mesh-free plates prepared with laser ablation. The pitch-to-diameter ratio in the configuration of 10-µm-diameter holes needs to be larger than 2.5 times for printing a resin having a viscosity of 12,800 mPa s.

  6. Flow lithography in ultraviolet-curable polydimethylsiloxane microfluidic chips.

    Science.gov (United States)

    Kim, Junbeom; An, Heseong; Seo, Yoojin; Jung, Youngmee; Lee, Jong Suk; Choi, Nakwon; Bong, Ki Wan

    2017-03-01

    Flow Lithography (FL) is the technique used for the synthesis of hydrogel microparticles with various complex shapes and distinct chemical compositions by combining microfluidics with photolithography. Although polydimethylsiloxane (PDMS) has been used most widely as almost the sole material for FL, PDMS microfluidic chips have limitations: (1) undesired shrinkage due to the thermal expansion of masters used for replica molding and (2) interfacial delamination between two thermally cured PDMS layers. Here, we propose the utilization of ultraviolet (UV)-curable PDMS (X-34-4184) for FL as an excellent alternative material of the conventional PDMS. Our proposed utilization of the UV-curable PDMS offers three key advantages, observed in our study: (1) UV-curable PDMS exhibited almost the same oxygen permeability as the conventional PDMS. (2) The almost complete absence of shrinkage facilitated the fabrication of more precise reverse duplication of microstructures. (3) UV-cured PDMS microfluidic chips were capable of much stronger interfacial bonding so that the burst pressure increased to ∼0.9 MPa. Owing to these benefits, we demonstrated a substantial improvement of productivity in synthesizing polyethylene glycol diacrylate microparticles via stop flow lithography, by applying a flow time (40 ms) an order of magnitude shorter. Our results suggest that UV-cured PDMS chips can be used as a general platform for various types of flow lithography and also be employed readily in other applications where very precise replication of structures on micro- or sub-micrometer scales and/or strong interfacial bonding are desirable.

  7. A New Hard Coat on Cover Layer for Cartridge-Free Blu-ray Disc

    Science.gov (United States)

    Han, Mi Young; Kang, Tae-Sik; Lee, Seong-Keun; Jang, Sung Hoon; Seo, Hun; Lee, Chang-Ho

    2004-07-01

    A new UV-curable hard coat resin with an excellent antifouling property has been developed. A 3-μm-thick hard coat layer was stacked onto a 97-μm-thick cover layer by spin coating. The characteristics of the hard coat layer, such as pencil hardness, microscratch resistance, adhesion, water contact angle and jitter, have been investigated.

  8. Chemotherapy: Is it Warranted in Curable Head and Neck Cancer?

    Institute of Scientific and Technical Information of China (English)

    GuiyiTu

    2004-01-01

    Since the last century, many physicians have been trying to utilize chemotherapy to replace conventional surgical treatment for cases of cancer of the oropharynx, larynx, and hypopharynx, which would otherwise be candidates for total laryngectomy. Some authors claim that the preservation rate of the larynx increases after treatment by chemotherapy, which even may take the place of routine surgical methods. However, when calculated in a more rigorous way following accepted statistical methods, what they claim is questionable. As a result, the routine application of chemotherapy in its present form is not advisable for curable squamous cell carcinoma of the head and neck region. Further research is required to justify its benefit.

  9. Thermo-curable epoxy systems for nanoimprint lithography

    Science.gov (United States)

    Wu, Chun-Chang; Lien-Chung Hsu, Steve

    2010-01-01

    In this work, we have used solvent-free thermo-curable epoxy systems for low-pressure and moderate-temperature nanoimprint lithography (NIL). The curing kinetic parameters and conversion of diglycidyl ether of bisphenol A (DGEBA) resin with different ambient-cure 930 and 954 hardeners were studied by the isothermal DSC technique. They are useful for the study of epoxy resins in the imprinting application. The DGEBA/930 and DGEBA/954 epoxy resists can be imprinted to obtain high-density nano- and micro-scale patterns on a flexible indium tin oxide/poly(ethylene terephthalate) (ITO/PET) substrate. The DGEBA/930 epoxy resin is not only suitable for resist material, but also for plastic mold material. Highly dense nanometer patterns can be successfully imprinted using a UV-curable resist from the DGEBA/930 epoxy mold. Using the replicated DGEBA/930 epoxy mold instead of the expensive master can prevent brittle failure of the silicon molds in the NIL.

  10. Radiosensitivity, radio-curability and DNA repair; Radiosensibilite, radiocurabilite et reparation

    Energy Technology Data Exchange (ETDEWEB)

    Vogin, G. [Centre Alexis-Vautrin, 6, avenue de Bourgogne, 54511 Vandoeuvre-les-Nancy (France)

    2011-07-15

    Improvements in accuracy stand as the heart of the success of today's radiotherapy. The dose may be delivered with a sub millimetric accuracy, may also conform to complex shapes, or track external and internal organ motions. In parallel, we may increase the tumour's radio-curability by modulating the biological effects generated by ionizing radiation into the patient. It was precisely the topic of the 2009 Lucien-Mallet prize organized by the French Society for Radiation Oncology (SFRO) and the Centre Antoine-Beclere under the auspices of the Fondation de France. In this review we will precisely describe the integrated molecular response to ionizing radiations. Starting from early observations, we are going to introduce the concept of cellular radiosensitivity as the global response of the irradiated cell. We will then focus into the cell and especially its nucleus. We will describe here the most complex and deleterious radioinduced damages. In the next chapter, we will dissect the molecular pathway that aims to detect and repair the previous lesions. The last part of the review will finally deal with the diagnostic, prognostic and therapeutic impacts emerging from the alliance between clinical and molecular radiobiology. (author)

  11. The effect of UV radiation from oxygen and argon plasma on the adhesion of organosilicon coatings on polypropylene

    Science.gov (United States)

    Jaritz, M.; Behm, H.; Hopmann, Ch; Kirchheim, D.; Mitschker, F.; Awakowicz, P.; Dahlmann, R.

    2017-01-01

    The influence of ultraviolet (UV) radiation from oxygen and argon pretreatment plasmas on a plastic substrate has not been fully understood yet. In particular, its influence on the adhesion properties has not been sufficiently researched so far. This paper addresses this issue by comparing the bond strength of a plasmapolymerized silicon organic coating (SiO x C y H z ) on polypropylene (PP) after oxygen and argon plasma pretreatment and pretreatment by UV radiation emitted by the same plasmas. The UV radiation is isolated from the other species from the plasma by means of a magnesium fluoride (MgF2) optical filter. It could be shown that UV radiation originating from an oxygen plasma has a significant impact on both substrate surface chemistry and coating adhesion. The same maximum bond strength enhancement can be reached by pretreating the polypropylene surface either with pulsed oxygen plasma, or with only the UV radiation from this oxygen plasma. Also, similar surface chemistry and topography modifications are induced. For argon plasma no significant influence of its UV radiation on the substrate could be observed in this study.

  12. Survival of Staphylococcus aureus exposed to UV radiation on the surface of ceramic tiles coated with TiO2.

    Science.gov (United States)

    Szczawiński, J; Tomaszewski, H; Jackowska-Tracz, A; Szczawińska, M E

    2011-01-01

    The aim of this study was to determine and compare the antimicrobial activity of UV radiation of wavelength 253.7 nm (used in typical germicidal lamps) against Staphylococcus aureus on the surfaces of conventionally produced white ceramic wall tiles (matt and shiny) and the same tiles coated with TiO2 using three different methods: RF diode sputtering, atmospheric pressure chemical vapour deposition (APCVD) and spray pyrolysis deposition (SPD). Results clearly indicate that the bactericidal action of UV radiation is much stronger on the surfaces of tiles coated with TiO2 than on the tiles uncovered. The strongest bactericidal effect of UV radiation was found for film prepared by APCVD. Results of experiments for shiny and matt tiles did not differ statistically. The use of ceramic wall tiles coated with TiO2 films in hospitals, veterinary clinics, laboratories, food processing plants and other places where UV radiation is applied for disinfection should greatly improve the efficiency of this treatment.

  13. Halogen free benzoxazine based curable compositions for high T.sub.g applications

    Energy Technology Data Exchange (ETDEWEB)

    Tietze, Roger; Nguyen, Yen-Loan

    2016-08-16

    A method for forming a halogen-free curable composition containing a benzoxazine monomer, at least one epoxy resin, a catalyst, a toughening agent and a solvent. The halogen-free curable composition is especially suited for use in automobile and aerospace applications since the composition, upon curing, produces a composite having a high glass transition temperature.

  14. Functionalised polysiloxanes as injectable, in situ curable accommodating intraocular lenses.

    Science.gov (United States)

    Hao, Xiaojuan; Jeffery, Justine L; Wilkie, John S; Meijs, Gordon F; Clayton, Anthony B; Watling, Jason D; Ho, Arthur; Fernandez, Viviana; Acosta, Carolina; Yamamoto, Hideo; Aly, Mohamed G M; Parel, Jean-Marie; Hughes, Timothy C

    2010-11-01

    The aged eye's ability to change focus (accommodation) may be restored by replacing the hardened natural lens with a soft gel. Functionalised polysiloxane macromonomers, designed for application as an injectable, in situ curable accommodating intraocular lens (A-IOL), were prepared via a two-step synthesis. Prepolymers were synthesised via ring opening polymerisation (ROP) of octamethylcyclotetrasiloxane (D(4)) and 2,4,6,8-tetramethylcyclotetrasiloxane (D(4)(H)) in toluene using trifluoromethanesulfonic acid (TfOH) as catalyst. Hexaethyldisiloxane (HEDS) was used as the end group to control the molecular weight of the prepolymers, which were then converted to macromonomers by hydrosilylation of the SiH groups with allyl methacrylate (AM) to introduce polymerisable groups. The resulting macromonomers had an injectable consistency and thus, were able to be injected into and refill the empty lens capsular bag. The macromonomers also contained a low ratio of polymerisable groups so that they may be cured on demand, in situ, under irradiation of blue light, in the presence of a photo-initiator, to form a soft polysiloxane gel (an intraocular lens) in the eye. The pre-cure viscosity and post-cure modulus of the polysiloxanes, which are crucial factors for an injectable, in situ curable A-IOL application, were controlled by adjusting the end group and D(4)(H) concentrations, respectively, in the ROP. The macromonomers were fully cured within 5 min under light irradiation, as shown by the rapid change in modulus monitored by photo-rheology. Ex vivo primate lens stretching experiments on an Ex Vivo Accommodation Simulator (EVAS) showed that the polysiloxane gel refilled lenses achieved over 60% of the accommodation amplitude of the natural lens. An in vivo biocompatibility study in rabbits using the lens refilling (Phaco-Ersatz) procedure demonstrated that the soft gels had good biocompatibility with the ocular tissue. The polysiloxane macromonomers meet the targeted

  15. Nanoscale TiO₂-coated LPGs as radiation-tolerant humidity sensors for high-energy physics applications.

    Science.gov (United States)

    Consales, Marco; Berruti, Gaia; Borriello, Anna; Giordano, Michele; Buontempo, Salvatore; Breglio, Giovanni; Makovec, Alajos; Petagna, Paolo; Cusano, Andrea

    2014-07-15

    This Letter deals with a feasibility analysis for the development of radiation-tolerant fiber-optic humidity sensors based on long-period grating (LPG) technology to be applied in high-energy physics (HEP) experiments currently running at the European Organization for Nuclear Research (CERN). In particular, here we propose a high-sensitivity LPG sensor coated with a finely tuned titanium dioxide (TiO₂) thin layer (~100 nm thick) through the solgel deposition method. Relative humidity (RH) monitoring in the range 0%-75% and at four different temperatures (in the range -10°C-25°C) was carried out to assess sensor performance in real operative conditions required in typical experiments running at CERN. Experimental results demonstrate the very high RH sensitivities of the proposed device (up to 1.4 nm/% RH in correspondence to very low humidity levels), which turned out to be from one to three orders of magnitude higher than those exhibited by fiber Bragg grating sensors coated with micrometer-thin polyimide overlays. The radiation tolerance capability of the TiO₂-coated LPG sensor is also investigated by comparing the sensing performance before and after its exposure to a 1 Mrad dose of γ-ionizing radiation. Overall, the results collected demonstrate the strong potential of the proposed technology with regard to its future exploitation in HEP applications as a robust and valid alternative to the commercial (polymer-based) hygrometers currently used.

  16. Polyester based hybrid organic coatings

    Science.gov (United States)

    Wang, Xiaojiang

    Polyesters are a class of polymers widely used in organic coatings applications. In this work, four types of organic coatings based on polyester polyols were prepared: UV-curable polyester/poly(meth)acrylate coatings, thermal curable polyester polyurethane-urea coatings, thermal curable non-isocyanate polyurethane coatings, and UV-curable non-isocyanate polyurethane coatings. Polyester/poly(meth)acrylate block copolymers are synthesized using a combination of polycondensation and Atom-Transfer Radical Polymerization (ATRP). All block copolymers are characterized by means of Nuclear Magnetic Resonance (NMR) and Gel Permeation Chromatography (GPC). In the case of unsaturated-polyester-based block copolymers the main chain double bond in the polyester backbone remains almost unaffected during ATRP. The unsaturated block copolymers are crosslinkable and can form networks upon photo-irradiation in the presence of a suitable photoinitiator. These copolymers might be interesting candidates for coatings with better overall properties than those based on neat polyesters. Thermal curable polyester polyol based Polyurethane-Urea (PUU) coatings were formulated using Partially Blocked HDI isocyanurate (PBH), Isophorone Diamine (IPDA), and polyester polyol. As a comparison, the polyurethane coatings (PU) without adding IPDA were also prepared. The mechanical and viscoelastic properties of the PUU and PU coating were investigated by using tensile test and Dynamic Mechanical Thermal Analyzer (DMTA). It was found that PUU coating exhibited higher crosslink density, Tg, tensile modulus and strength than the corresponding PU coating. Thermal curable non-isocyanate polyurethane coatings were prepared by using polyamine and cyclic carbonate terminated polyester. Cyclic carbonate terminated polyester was synthesized from the reaction of the carbon dioxide and epoxidized polyester which was prepared from the polyester polyol. The properties of the epoxidized and cyclic carbonate

  17. Investigation on the Ability of Antireflection Coating to Withstand the Destructive Effects of Laser Radiation in IR Range (10.6 Micrometers),

    Science.gov (United States)

    2014-09-26

    at the mid-IR, KCl and NaCl are commonly selected as substrates. But for the CO2 laser , a Ge substrate coated with a *i ZnS AR coating, is still widely...intensity of the laser increases, these microscopic damages interact with the laser , thus absorbing more energy from the light field, and the...FOREIGN TECHNOLOGY DIVISION INVESTIGATION ON THE ABILITY OF ANTIREFLECTION COATING TO WITHSTAND THE DESTRUCTIVE EFFECTS OF LASER RADIATION IN IR RANGE

  18. Synthesis of a Novel UV-curable Prepolymer Polypropyleneglycol Diglycidyl Ether Diacrylate

    Institute of Scientific and Technical Information of China (English)

    HUANG Biwu; HUANG Bofen; DU Guoping; CHEN Weiqing

    2008-01-01

    A novel UV-curable prepolymer polypropyleneglycol diglycidyl ether diacrylate(PPGGEA) was synthesized by utilizing polypropyleneglycol diglycidyl ether(PPGGE)and acrylic acid(AA)as starting materials,N,N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor.The optimum synthetic conditions were in the following:the concentration of N,N-dimethylbenzylamine was 0.80 wt% of reactants,the concentration of p-hydroxyanisole was 0.3 wt%of reactants.the reaction temperature was 90-110℃,and the molar ratio of PPGGE to AA was 1:2.2.Meanwhile,1-hydroxycyclOhexyl phenyl ketone of a UV-cured initiator was added to the synthesized PPGGEA to prepare a kind of UV-cured coating.The mechanical properties of the UV-cured films were determined,giving 29.99 MPa of tensile strength,834.27 MPa of the Young'S modulus and 5.66%of elongation at tear.

  19. Optimized design and fabrication of nanosecond response electro optic switch based on ultraviolet-curable polymers

    Institute of Scientific and Technical Information of China (English)

    赵旭亮; 岳远斌; 刘通; 孙健; 王希斌; 孙小强; 陈长鸣; 张大明

    2015-01-01

    A nanosecond response waveguide electro-optic (EO) switch based on ultraviolet (UV) sensitive polymers of Norland optical adhesive (NOA73) and Dispersed Red 1 (DR1) doped SU-8 (DR1/SU-8) is designed and fabricated. The absorption properties, refractive indexes, and surface morphologies of NOA73 film are characterized. The single-mode transmission condition is computed by the effective index method, and the percentage of optical field distributed in EO layer is optimized to be 93.78%. By means of spin-coating, thermal evaporation, photolithography, and inductively coupled plasma etching, a Mach–Zehnder inverted-rib waveguide EO switch with micro-strip line electrode is fabricated on a silicon substrate. Scanning electron microscope characterization proves the physic-chemical compatibility between NOA73 cladding and DR1/SU-8 core material. The optical transmission loss of the fabricated switch is measured to be 2.5 dB/cm. The rise time and fall time of switching are 3.199 ns and 2.559 ns, respectively. These results indicate that the inverted-rib wave-guide based on UV-curable polymers can effectively reduce the optical transmission loss and improve the time response performance of an EO switch.

  20. 硅氧烷改性双酚S环氧丙烯酸酯/聚氨酯丙烯酸酯水性涂料的固化动力学与性能%Curing Kinetics and Performance of Waterborne UV-Curable Siloxane Modified Bisphenol S Epoxy Acrylate/PU-Acrylate Coating

    Institute of Scientific and Technical Information of China (English)

    朱风利; 高俊刚; 杨建波; 刘孝谦

    2012-01-01

    An anionic polyurethane acrylate was prepared,which was used as the emulsifier for prapra-tion of methylacryloylpropyl trimethoxysilane ( MAPTMS ) modified bisphenol S eopxy acrylate ( BPSA ) /polyurethane acrlylate based waterborne coating. The coating were characterized by FT - IR,DSC and DMA. FT - IR results showed that the coating can be UV cured. The DSC and DMA analysis indicated that the radical initiated non - isothermal curing reaction could be described by a two - parameter autocatalytic Sestak -Berggren (S-B) kinetic model. The three components in the system were well compatible and MAPTMS could improve the thermal properties of coating film. The glass transition temperature Tg reached the highest when the amount of MAPTMS was 8% ,which was increased by 11.5℃ than the pure system. The coating film showed better alkali -acid resistance,adhesion and hardness.%制备了阴离子型聚氨酯丙烯酸酯,并以此为乳化剂制备了甲基丙烯酰氧丙基三甲氧基硅烷( MAPTMS)改性的双酚S环氧丙烯酸酯(BPSA)/聚氨酯丙烯酸酯(PUA)水性涂料.FT - IR研究表明,该涂料可使用紫外光进行固化;差示扫描量热仪( DSC)及动态力学谱仪(DMA)等研究分析表明,自由基引发的非等温固化反应可用自催化(s)esták - Berggren(S-B)动力模型描述,该组分体系具有良好的相容性,MAPTMS的加入可改善涂膜的热性能,当硅烷偶联剂含量为8%时,玻璃化温度Tg达到最大,与纯组分相比提高了11.5℃.光固化涂层有很好的耐酸/碱性、附着力和硬度.

  1. Synthesis of a novel UV-curable prepolymer neopentyl glycol diglycidyl ether diacrylate and its cured film tensile property

    Institute of Scientific and Technical Information of China (English)

    HUANG Bi-wu; HUANG Bo-fen; CHEN Wei-qing; OUYANG Zhi-qiang

    2009-01-01

    A novel UV-curable prepolymer neopentyl glycol diglycidyl ether diacrylate(NPGGEA)was synthesized by using neopentyl glycol diglycidyl ether(NPGGE)and acrylic acid(AA)as starting materials, N, N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor. The optimum synthetic conditions were taken as follows: The concentration of N,N-dimethylbenzylamine, 0.80% of reactants; the concentration of p-hydroxyanisole, 0.3% of reactants; the reaction temperature, 90-110℃; the molar ratio of NPGGE to AA, 1:2.2. Meanwhile, 1-hydroxycyclohexyl phenyl ketone of a UV-cured initiator was added to the synthesized NPGGEA to prepare a kind of UV-cured coating. Mechanical properties of the UV-cured films were determined, giving 28.75 MPa of tensile strength, 923.82 MPa of Young's modulus and 5.51% of elongation at tear.

  2. Synthesis of a Novel UV-curable Prepolymer Hexanediol Diglycidyl Ether Diacrylate and Its Cured Film Tensile Property

    Institute of Scientific and Technical Information of China (English)

    HUANG Biwu; CHEN Weiqing; YANG Zhihong; JIANG Ankun; WENG Zixiang

    2011-01-01

    A novel UV-curable prepolymer hexanediol diglycidyl ether diacrylate (HDGEA)was synthesized by utilizing hexanediol diglycidyl ether (HDGE) and acrylic acid (AA) as starting materials, N, N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor. The optimal synthetic conditions were that the concentration of N, N-dimethylbenzylamine was 0.80 wt% of reactants, the concentration of p-hydroxyanisole was 0.3 wt% of reactants, the reaction temperature was 90-110 ℃, and the molar ratio of HDGE to AA was 1 ∶ 2.2. Meanwhile, 1-hydroxycyclohexyl phenyl ketone of a UV-curing initiator was added to the synthesized HDGEA to prepare a kind of UV-curing coating. The mechanical properties of the UV-cured films were determined, giving 31.87 MPa of tensile strength, 871.88 MPa of Young's modulus and 6.77% of elongation at tear.

  3. Hybrid thin films derived from UV-curable acrylate-modified waterborne polyurethane and monodispersed colloidal silica

    Directory of Open Access Journals (Sweden)

    C. H. Yang

    2012-01-01

    Full Text Available Hybrid thin films containing nano-sized inorganic domains were synthesized from UV-curable acrylate-modified waterborne polyurethane (WPU-AC and monodispersed colloidal silica with coupling agent. The coupling agent, 3-(trimethoxysilylpropyl methacrylate (MSMA, was bonded onto colloidal silica first, and then mixed with WPU-AC to form a precursor solution. This precursor was spin coated, dried and UV-cured to generate the hybrid films. The silica content in the hybrid thin films was varied from 0 to 30 wt%. Experimental results showed the aggregation of silica particles in the hybrid films. Thus, the silica domain in the hybrid films was varied from 30 to 50 nm by the different ratios of MSMAsilica to WPU-AC. The prepared hybrid films from the crosslinked WPU-AC/MSMA-silica showed much better thermal stability and mechanical properties than pure WPU-AC.

  4. Cost-effective fabrication of waveguides for PLCs by replication in UV-curable sol-gel material

    Science.gov (United States)

    Gimkiewicz, Christiane; Thiele, Hans D.; Zschokke, Christian; Mahmud-Skender, Sanida; Westenhofer, Susanne; Gale, Michael T.

    2004-08-01

    A new wafer-scale replication process for fabricating buried ridge waveguides for telecom/datacom applications using an uv-curable sol-gel material is proposed. Spin coating of the core material on the replication mould is used to form the waveguide cores with a smooth thin layer. The spin parameters allow an accurate control of the thickness and homogeneity. The bottom-cladding is uv-cast between a substrate and the mould, which is covered by the spun core layer. The ridge waveguide cores are demoulded and buried under a top cladding. This process allows the stacking of several layers of waveguides on top of each other to form two-dimensional waveguide arrays. A specially adapted SUSS mask aligner is used to control the cladding thickness between individual waveguide layers and to align them. A waveguide loss comparable to lithographically fabricated waveguides has been achieved.

  5. The effects of ionizing radiation, temperature, and space contamination effects on self-cleaning and anti-contamination coatings

    Science.gov (United States)

    Pirich, Ronald; Weir, John; Leyble, Dennis

    2008-08-01

    A revolutionary family of cost-effective, lightweight, self-cleaning and anti-contamination coatings is being investigated to mitigate lunar dust on critical power and optical systems, including solar photovoltaic power systems, radiators, and other components needed for lunar exploration as well as optical instruments and sensors. Dust contamination is a serious problem for equipment and vehicles since Lunar "weathering" has left the lunar soil has fine texture compared to terrestrial dust particle size distributions. The electrostatic charging of the lunar surface is caused by its interaction with the local plasma environment and solar UV and X-rays induced photoemission of electrons. The lunar thermal environment poses unique challenges to coatings since it is characterized by large temperature variations, long hot and cold soak times, and reduced heat rejection capability due to the presence of the lunar regolith. We are attempting to design an integrated approach to solving the dust problems associated with its many elements This presentation will discuss the properties, as a function of ionizing radiation, temperature and space contamination effects, for both hydrophilic and hydrophobic coating self-cleaning approaches as well as a new approach which incorporates various catalytic mechanisms (stoichiometric, photocatalytic and electrocatalytic) for decontamination in the lunar environment.

  6. Flame Retardant and Thermal Stability of Novel Hybrid Multi-Curable Epoxy Acrylate/Nano-SiO2 Transparent Coating%多重固化EA/纳米SiO2杂化涂层的阻燃及热稳定性

    Institute of Scientific and Technical Information of China (English)

    杨磊; 吴丹丹; 沈惠珍; 谢琼琼; 冯其

    2012-01-01

    以改性纳米SiO2、γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH.570)、磷酸酯三丙烯酸酯(TEAP)及TDI-TMP加成物作紫外(uv)配方体系的功能成分,制备了含P、N及Si三重固化丙烯酸酯涂层。通过红外、紫外-可见、热重及阻燃性能测试仪等研究了不同阻燃体系下不同固化方式对环氧丙烯酸酯(EA)涂层阻燃及热稳定性能的影响。结果表明:EA体系双键转化率随纳米SiO2含量及固化重数的增加而提高;可见光透过率随KH-570、TDI-TMP的加入而改善;涂层阻燃及热稳定性随阻燃成分与其含量,及固化重数的增加而提高。%Triple-curing acrylic coatings containing P-N-Si were prepared, with modified nano-SiO2, 3,-methyl propylene acyloxy propyl trimethoxy silane(KH-570), phosphate three acrylate (TEAP)and TDI-TMP addition product as UV formula system's functional component. The effects of different flame retardant system and curing method on flame retardant and thermostability of epoxy acrylate (EA) coating weres studied by FT-IR, UV-Vis, TG, flame retardation measure instrument and so on. The result showed that C=C double bond conversion of EA system increased with nano-SiO2 content and curing layer number increasing, visible light transmittance was improved with KH-570 and TDI-TMP added, and that thermal stability and flame retardancy of acrylic coating were enhanced with flame retardant composition and its content and curing layer number increasing.

  7. Radiation processing of polyethylene

    Science.gov (United States)

    Barlow, A.; Biggs, J. W.; Meeks, L. A.

    This paper covers two areas (a) the use of high energy radiation for the synthesis and improvement of polymer properties and (b) the formulation of radiation curable compounds for automotive/appliance wire applications and high voltage insulation. The first part discusses the use of gamma radiation for the bulk polymerization of ethylene and the properties of the polymer produced. The use of low dose radiation to increase polymer molecular weight and modify polydispersity is also described together with its projected operational cost. An update is provided of the cost savings that can be realized when using radiation crosslinked heavy duty film, which expands its applications, compared with noncrosslinked materials. The second section of the paper considers the advantages and disadvantages of radiation vs. peroxide curing of wire and cable compounds. The formulation of a radiation curable, automotive/appliance wire compound is discussed together with the interactions between the various ingredients; i.e., base resin, antioxidants, flame retardant filler, coupling agents, processing aids and radiation to achieve the desired product. In addition, the general property requirements of a radiation curable polyethylene for high voltage insulation are discussed; these include crosslinking efficiency, thermal stability, wet tree resistance and satisfactory dielectric properties. Preliminary data generated in the development of a 230KV radiation crosslinked polyethylene insulation are included.

  8. Fiber optic probes based on silver-only coated hollow glass waveguides for ionizing beam radiation dosimetry

    Science.gov (United States)

    Darafsheh, Arash; Liu, Haoyang; Melzer, Jeffrey E.; Taleei, Reza; Harrington, James A.; Kassaee, Alireza; Zhu, Timothy C.; Finlay, Jarod C.

    2016-03-01

    Čerenkov contamination is a significant issue in radiation detection by fiber-coupled scintillators. To enhance the scintillation signal transmission while minimizing Čerenkov contamination, we designed a fiber probe using a silver-only coated hollow waveguide (HWG). The HWG tip with inserted scintillator, embedded in tissue mimicking phantoms, was irradiated with clinical electron and photon beams. Optical spectra of irradiated tips were taken using a fiber spectrometer, and the signal was deconvolved with a linear fitting algorithm. The resultant decomposed spectra of the scintillator with and without Čerenkov correction were in good agreement with measurements performed by an electron diode and ion chamber for electron and photon beam dosimetry, respectively, indicating the minimal effect of Čerenkov contamination. Compared with a silver/dielectric coated HWG fiber dosimeter design we observed higher signal transmission in our design based on the use of silver-only HWG.

  9. 3D inkjet-printed UV-curable inks for multi-functional electromagnetic applications

    OpenAIRE

    Saleh, Ehab; Woolliams, Peter; Clarke, Bob; Gregory, Andrew; Greedy, Steve; Smartt, Chris; Ricky D. Wildman; Ashcroft, Ian; Hague, Richard J.M.; Dickens, Phill; Tuck, Christopher

    2017-01-01

    Inkjet printing of multiple materials is usually processed in multiple steps due to various jetting and curing/sintering conditions. In this paper we report on the development of all inkjet-printed UV-curable electromagnetic responsive inks in a single process, and the electromagnetic characterization of the developed structure. The ink consists of iron oxide (Fe3O4) nanoparticles (nominal particle size 50–100 nm) suspended within a UV curable matrix resin. The viscosity and surface tension o...

  10. Arrayed Lensed Fibers Collectively Fabricated Utilizing UV-Curable Fluorinated Polymer

    Institute of Scientific and Technical Information of China (English)

    Kyung-Rok; Kim; Manjung; Han; Selee; Chang; K.; Oh

    2003-01-01

    A novel fabrication method for lensed fiber array has been proposed utilizing UV-curable fluorinated polymer, whose refractive index is matched to fused silica. The structure is composed of three segments; single mode fiber, coreless silica fiber and UV-curable polymer lens-tip. Flexible control of the curvature of lens-tip was realized by control of deposited volume of the liquid polymer and free-space interconnection performances are characterized.

  11. MODIFIED ULTRAVIOLET-CURABLE WATER DISPERSIBLE POLYURETHANE-ACRYLATES

    Institute of Scientific and Technical Information of China (English)

    Jian-wen Yang; Zhi-ming Wang; Zhao-hua Zeng; Hui-ya Yuan; Yong-lie Chen

    2001-01-01

    Three kinds of UV-curable self-emulsified polyurethane-acrylate (PUA) prepolymer, i.e., conventional, chain extended and grafted PUAs, were prepared. The relatively small particle size of the PUA dispersions indicates that the PUA prepolymers exhibit sufficient aqueous dispersibility. The PUA prepolymers can substantially lower the interfacial tension of water. Chain-extended PUA dispersions exhibit pseudoplastic behavior and thixotropy to a greater extent than do their conventional counterpart. The chain-extended and grafted PUA photocure to higher conversion than do the conventional PU equivalent. The results of DSC measurement suggest that there exists phase mixing between the hard and the soft segment phases for the PUAs based on PEG 400 that is the comparatively short soft segment in the prepolymer. For the PUA prepolvmers based on PEG having higher Mn values, chain-extending and grafting could impede the phase separation between the hard and the soft segment domains. The adhesion, impact strength and flexibility of the photocured films were tested.

  12. Solar absorptance of copper–cobalt oxide thin film coatings with nano-size, grain-like morphology: Optimization and synchrotron radiation XPS studies

    Energy Technology Data Exchange (ETDEWEB)

    Amri, Amun [School of Engineering and Energy, Murdoch University, Murdoch, 6150 WA (Australia); Department of Chemical Engineering, Riau University, Pekanbaru (Indonesia); Duan, XiaoFei [School of Chemistry, The University of Melbourne, VIC 3010 (Australia); Yin, Chun-Yang, E-mail: c.yin@murdoch.edu.au [School of Chemical and Mathematical Sciences, Murdoch University, Murdoch, 6150 WA (Australia); Jiang, Zhong-Tao, E-mail: z.jiang@murdoch.edu.au [School of Engineering and Energy, Murdoch University, Murdoch, 6150 WA (Australia); Rahman, M. Mahbubur; Pryor, Trevor [School of Engineering and Energy, Murdoch University, Murdoch, 6150 WA (Australia)

    2013-06-15

    Copper–cobalt oxides thin films had been successfully coated on reflective aluminium substrates via a facile sol–gel dip-coating method for solar absorptance study. The optimum absorptance in the range of solar radiation is needed for further optimum design of this material for selective solar absorber application. Field emission scanning electron microscopy was used to characterize the surface morphology of the coating whereby nano-size, grain-like morphology was observed. Synchrotron radiation X-ray photoelectron spectroscopy was employed to analyze the electronic structure of the coated surface showing that the (i) oxygen consisted of lattice, surface and subsurface oxygen, (ii) copper consisted of octahedral and tetrahedral Cu{sup +}, as well as octahedral and paramagnetic Cu{sup 2+} oxidation states, and (iii) cobalt consisted of tetrahedral and paramagnetic Co(II), octahedral Co(III) as well as mixed Co(II,III) oxidation states. In order to optimize the solar absorptance of the coatings, relevant parameters such as concentrations of cobalt and copper, copper/cobalt concentration ratios and dip-speed were investigated. The optimal coating with α = 83.4% was produced using 0.25 M copper acetate and 0.25 M cobalt chloride (Cu/Co ratio = 1) with dip-speed 120 mm/min (four cycles). The operational simplicity of the dip-coating system indicated that it could be extended for coating of other mixed metal oxides as well.

  13. Fabrication of copper oxide-coated hollow waveguides for CO2 laser radiation.

    Science.gov (United States)

    Matsuura, Y; Miura, D; Miyagi, M

    1999-03-20

    Hollow fibers for transmitting CO(2) laser light were fabricated by the chemical vapor deposition (CVD) method. A dielectric film of copper oxide (Cu(2)O) was deposited upon the inside of a Ag-coated glass capillary by use of a metal acetylacetonate as the precursor. The waveguide, which was coated with Cu(2)O and had a bore diameter of 700 microm, showed a loss of 0.9 dB/m for CO(2) laser light. The Cu(2)O film deposited by CVD had high chemical and heat resistivity. Therefore a hollow fiber coated with copper oxide is suitable for high-power laser applications in a severe environment.

  14. Ambient temperature cured TiB2 cathode coating for aluminum electrolysis

    Institute of Scientific and Technical Information of China (English)

    赖延清; 李庆余; 杨建红; 李劼

    2003-01-01

    The concept of ambient temperature curable TiB2 cathode coating was put forward, and the ambient temperature curable TiB2 cathode coating was prepared successfully. Differing from the previous TiB2 cathode coating solidified approximately at 200 ℃,the ambient temperature curable TiB2 cathode coating can be solidified at room temperature, so the heating equipment is not necessary, which simplifies the preparation process and facilitates the industrial application of TiB2 cathode coating. Many kinds of resin and curing agent were investigated. On the above-mentioned basis, the ambient temperature curable TiB2 cathode coating was prepared with furan resin 5 500 mixed with complex resins B as carbon binder and DXG1 as curing agent in 24 h. The results show that the properties of prepared coating are excellent, the electrical resistivity is 29.8 μΩ*m, the compressive strength is 33.6 MPa, which are all better than the relevant properties of partially graphitized cathode carbon block for aluminum electrolysis prescribed by the GB 8744-88. SEM morphologies show that the section morphology of the TiB2 coating is unaltered during the electrolysis test, the TiB2 coating can be used in aluminum electrolysis industry to save energy and prolong the life of aluminum electrolysis cell.

  15. Chemotherapy curable malignancies and cancer stem cells: a biological review and hypothesis.

    Science.gov (United States)

    Savage, Philip

    2016-11-21

    Cytotoxic chemotherapy brings routine cures to only a small select group of metastatic malignancies comprising gestational trophoblast tumours, germ cell tumours, acute leukemia, Hodgkin's disease, high grade lymphomas and some of the rare childhood malignancies. We have previously postulated that the extreme sensitivity to chemotherapy for these malignancies is linked to the on-going high levels of apoptotic sensitivity that is naturally linked with the unique genetic events of nuclear fusion, meiosis, VDJ recombination, somatic hypermutation, and gastrulation that have occurred within the cells of origin of these malignancies. In this review we will examine the cancer stem cell/cancer cell relationship of each of the chemotherapy curable malignancies and how this relationship impacts on the resultant biology and pro-apoptotic sensitivity of the varying cancer cell types. In contrast to the common epithelial cancers, in each of the chemotherapy curable malignancies there are no conventional hierarchical cancer stem cells. However cells with cancer stem like qualities can arise stochastically from within the general tumour cell population. These stochastic stem cells acquire a degree of resistance to DNA damaging agents but also retain much of the key characteristics of the cancer cells from which they develop. We would argue that the balance between the acquired resistance of the stochastic cancer stem cell and the inherent chemotherapy sensitivity of parent tumour cell determines the overall chemotherapy curability of each diagnosis. The cancer stem cells in the chemotherapy curable malignancies appear to have two key biological differences from those of the more common chemotherapy incurable malignancies. The first difference is that the conventional hierarchical pattern of cancer stem cells is absent in each of the chemotherapy curable malignancies. The other key difference, we suggest, is that the stochastic stem cells in the chemotherapy curable malignancies

  16. The characteristics of sound radiation from a cylindrical shell coated with multiple compliant layers

    Institute of Scientific and Technical Information of China (English)

    TAO Meng; FAN Jun; TANG Weilin

    2009-01-01

    The effect of multiple compliant layers on sound radiation from a finite cylindrical shell immersed in an infinite acoustic medium is studied. The transfer matrix is derived according to the continuous boundary conditions at each adjacent interface of the multi-layer system.With the shell theory and the acoustic wave equation, the theoretical model is developed to estimate the characteristics of sound radiation. The numerical calculation results show that the amount of the acoustic radiation power reduction increases as the wave speed or the density of the compliant layer decreases, and using multi-layer system could be more effective on noise reduction than the corresponding uniform single layer.

  17. Research on vibration and near-field sound radiation of ring-ribbed cylindrical shell coated deadening and decoupling materials

    Institute of Scientific and Technical Information of China (English)

    YAO Xiong-liang; LIU Qing-jie; YU Xiu-bo

    2007-01-01

    The research on structural vibration and sound radiation of underwater ring-ribbed cylindrical shell, which is coated with a kind of deadening and decoupling materials, becomes a focus in recent years. This paper analyzes the problem on two aspects: model experiment and numerical calculation. The model experiment is carried out including three cases firstly, in which the structural vibration response and radiating acoustic field are measured respectively, and the results gained in these three cases are analyzed to discuss the effect of reducing structural vibration and radiating noise of the deadening and decoupling materials. The coupling FEM/BEM and the SEA methods are both used in numerical calculation, i.e. the arithmetic of the coupling FEM/BEM method is adopted to calculate the low frequency characteristics and the SEA method is adopted to calculate the medium-high frequencies characteristics of the model. By comparing experimental results with numerical calculation results, it is proved that the algorithm adopted in this paper is reasonable.

  18. Spin-Coating Technology of the Cover Layer for Digital Video Recording-Blue Disc

    Science.gov (United States)

    Komaki, Tsuyoshi; Hirata, Hideki; Usami, Mamoru; Ushida, Tomoki; Hayashida, Naoki; Inoue, Hiroyasu; Kato, Tatsuya; Shingai, Hiroshi; Utsunomiya, Hajime

    2002-06-01

    We have achieved the cover layer thickness distribution of 100± 1.5 μm on a disc by improving the spin-coating method and developing an original spin-coating machine. The small skew of the disc is achieved by using a newly developed UV-curable resin.

  19. ANALYSIS OF SOUND RADIATION FROM THE RING-STIFFENED CYLINDRICAL SHELL COATED WITH VISCOELASTIC LAYER IN FLUID MEDIUM

    Institute of Scientific and Technical Information of China (English)

    LuoDonning; CaiMinbo; PengXu; LuoBin

    2003-01-01

    The Donnell theory of shell is applied to describe shell motion and layer motion is described by means of three-dimensional Navier equations. Using deformation harmonious conditions of the interface, the effects of stiffeners and layer are treated as reverse forces and moments acting on the cylindrical shell. In studying the acoustic field produced by vibration of the submerged ring-stiffened cylindrical coated shell, the structure dynamic equation, Helmholtz equation in the fluid field and the continuous conditions of the fluid-structure interface compose the cou-pling vibration equation of the sound-fluid-structure. The extract of sound pressure comes down to the extract of coupling vibration equation. By use of the solution of the equation, the influences of hydrostatic pressure, physical characters and geometric parameters of the layer on sound radiation are discussed.

  20. Curable liquid hydrocarbon prepolymers containing hydroxyl groups and process for producing same

    Science.gov (United States)

    Rhein, R. A.; Ingham, J. D. (Inventor)

    1978-01-01

    Production of hydroxyl containing curable liquid hydrocarbon prepolymers by ozonizing a high molecular weight saturated hydrocarbon polymer such as polyisobutylene or ethylene propylene rubber is discussed. The ozonized material is reduced using reducing agents, preferably diisobutyl aluminum hydride, to form the hydroxyl containing liquid prepolymers having a substantially lower molecular weight than the parent polymer. The resulting curable liquid hydroxyl containing prepolymers can be poured into a mold and readily cured, with reactants such as toluene diisocyanate, to produce highly stable elastomers having a variety of uses such as binders for solid propellants.

  1. Accompanying of parameters of color, gloss and hardness on polymeric films coated with pigmented inks cured by different radiation doses of ultraviolet light

    Science.gov (United States)

    Bardi, Marcelo Augusto Gonçalves; Machado, Luci Diva Brocardo

    2012-09-01

    In the search for alternatives to traditional paint systems solvent-based, the curing process of polymer coatings by ultraviolet light (UV) has been widely studied and discussed, especially because of their high content of solids and null emission of VOC. In UV-curing technology, organic solvents are replaced by reactive diluents, such as monomers. This paper aims to investigate variations on color, gloss and hardness of print inks cured by different UV radiation doses. The ratio pigment/clear coating was kept constant. The clear coating presented higher average values for König hardness than pigmented ones, indicating that UV-light absorption has been reduced by the presence of pigments. Besides, they have indicated a slight variation in function of cure degree for the studied radiation doses range. The gloss loss related to UV light exposition allows inferring that some degradation occurred at the surface of print ink films.

  2. Performance of paint coatings in the radiation fields of nuclear reactors and of high energy particle accelerators and after contamination by radionuclides

    CERN Document Server

    Schönbacher, Helmut; Oesterle, K M; Van de Voorde, M

    1977-01-01

    Several commercially available two/component coating systems based on epoxy and polyurethane resin, as well as lithium silicate/zinc dust paint coatings, have been irradiated in a nuclear reactor up to a dose of 2*10/sup 9/ rad and in a 28 GeV proton accelerator up to a dose of 1*10/sup 9/ rad. Besides assessment by visual inspection, the irradiated specimens have been subjected to the impact hardness test, the infinitesimal hardness behaviour tests, the grid scarification test and to swelling tests in methanol and acetone. The decontaminability of these paint coatings after contamination with solutions containing Ca 45, S 35 and I 131 is also investigated. Very good results in respect of decontaminability and radiation resistance up to 1*10/sup 9/ rad have been obtained with a coating of polyurethane cross-linked with an aliphatic diisocyanate. (9 refs).

  3. UV-curable nanocomposite based on methacrylic-siloxane resin and surface-modified TiO2 nanocrystals.

    Science.gov (United States)

    Ingrosso, Chiara; Esposito Corcione, Carola; Striani, Raffaella; Comparelli, Roberto; Striccoli, Marinella; Agostiano, Angela; Curri, M Lucia; Frigione, Mariaenrica

    2015-07-22

    A novel UV-light-curable nanocomposite material formed of a methacrylic-siloxane resin loaded with 1 wt % oleic acid and 3-(trimethoxysilyl)propyl methacrylate silane (OLEA/MEMO)-coated TiO2 nanorods (NRs) has been manufactured as a potential self-curing structural coating material for protection of monuments and artworks, optical elements, and dental components. OLEA-coated TiO2 NRs, presynthesized by a colloidal chemistry route, have been surface-modified by a treatment with the methacrylic-based silane coupling agent MEMO. The resulting OLEA/MEMO-capped TiO2 NRs have been dispersed in MEMO; that is a monomer precursor of the organic formulation, used as a "common solvent" for transferring the NRs in prepolymer components of the formulation. Differential scanning calorimetry and Fourier transform infrared spectroscopy have allowed investigation of the effects of the incorporation of the OLEA/MEMO-capped TiO2 NRs on reactivity and photopolymerization kinetics of the nanocomposite, demonstrating that the embedded NRs significantly increase curing reactivity of the neat organic formulation both in air and inert atmosphere. Such a result has been explained on the basis of the photoactivity of the nanocrystalline TiO2 which behaves as a free-radical donor photocatalyst in the curing reaction, finally turning out more effective than the commonly used commercial photoinitiator. Namely, the NRs have been found to accelerate the cure rate and increase cross-linking density, promoting multiple covalent bonds between the resin prepolymers and the NR ligand molecules, and, moreover, they limit inhibition effect of oxygen on photopolymerization. The NRs distribute uniformly in the photocurable matrix, as assessed by transmission electron microscopy analysis, and increase glass transition temperature and water contact angle of the nanocomposite with respect to the neat resin.

  4. Decreasing the radiation quality factor of magnetic dipole antennas by a magnetic-coated metal core

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.; Breinbjerg, Olav

    2010-01-01

    To achieve the Chu lower bound for the radiation Q, an electrically small magnetic dipole antenna should not store any magnetic energy internally to the minimum sphere enclosing the antenna. As shown in our previous works, the internal stored magnetic energy can be reduced, although not entirely...

  5. Electrically templated dewetting of a UV-curable prepolymer film for the fabrication of a concave microlens array with well-defined curvature.

    Science.gov (United States)

    Li, Xiangming; Tian, Hongmiao; Ding, Yucheng; Shao, Jinyou; Wei, Yuping

    2013-10-23

    This paper presents an economic method, based on electrically templated dewetting of a UV-curable prepolymer, for fabricating a concave microlens array (MLA) of high quality and high density. In our strategy, a voltage is applied to an electrode pair consisting of a conductive substrate coated with a UV-curable prepolymer film and a microhole-arrayed silicon template, sandwiching an air gap, to dewet the prepolymer film into a curved air-liquid interface. At or beyond a critical voltage, the curved prepolymer can be pulled quickly into contact with the protrusive underside of the silicon template. Contact of the prepolymer with the template can be detected by monitoring the leaky current in the polymer, followed by a UV curing of the prepolymer. Finally, by separating the mold from the solidified polymer, a concave MLA is obtained. The curvature of the MLA can be well-defined simply by changing the air gap between the mold and prepolymer film. Besides, the dewetting strategy results in a much smaller adhesion area between the mold and solidified polymer structures, which allows for easy separation of the mold from the MLA in a large-area operation.

  6. Direct measurement of colloidal interactions between polyaniline surfaces in a uv-curable coating formulation

    DEFF Research Database (Denmark)

    Jafarzadeh, Shadi; Claesson, Per M.; Pan, Jinshan

    2014-01-01

    The interactions between polyaniline particles and polyaniline surfaces in polyester acrylate resin mixed with 1,6-hexanediol diacrylate monomer have been investigated using contact angle measurements and the atomic force microscopy colloidal probe technique. Polyaniline with different characteri......The interactions between polyaniline particles and polyaniline surfaces in polyester acrylate resin mixed with 1,6-hexanediol diacrylate monomer have been investigated using contact angle measurements and the atomic force microscopy colloidal probe technique. Polyaniline with different...... characteristics (hydrophilic and hydrophobic) were synthesized directly on spherical polystyrene particles of 10 μm in diameter. Surface forces were measured between core/shell structured polystyrene/polyaniline particles (and a pure polystyrene particle as reference) mounted on an atomic force microscope...... cantilever and a pressed pellet of either hydrophilic or hydrophobic polyaniline powders, in resins of various polymer:monomer ratios. A short-range purely repulsive interaction was observed between hydrophilic polyaniline (doped with phosphoric acid) surfaces in polyester acrylate resin. In contrast...

  7. Effects of ionizing radiation and temperature on hydrophobic self-cleaning photonic coatings

    Science.gov (United States)

    Pirich, Ronald G.; Weir, John; Leyble, Dennis; Digiuseppe, Michael

    2009-10-01

    Dust contamination is a serious problem for equipment and vehicles for space mission applications. Dust contamination gathers on photonic sensors inhibiting motion and data gathering. In addition, devices that require transparency to light for maximum efficiency such as solar photovoltaic power systems, video cameras and optical or infrared detectors will suffer from the dust accumulation. For example, on the lunar surface, regolith (lunar dust) contamination is a serious problem for equipment and vehicles since the lunar soil has fine texture compared to terrestrial dust particle size distributions. The electrostatic charging of the lunar surface is caused by its interaction with the local plasma environment and solar UV and X-rays induced photoemission of electrons. The lunar thermal environment poses unique challenges to coatings since it is characterized by large temperature variations, long hot and cold soak times, and reduced heat rejection capability due to the presence of the lunar regolith. Fundamental forces (van der Waals) allow certain contamination to adhere to critical photonic surfaces and can be mitigated using various passive coatings phenomenology (hydrophilic to hydrophobic).

  8. Embedded top-coat for reducing the effect out of band radiation in EUV lithography

    Science.gov (United States)

    Du, Ke; Siauw, Meiliana; Valade, David; Jasieniak, Marek; Voelcker, Nico; Trefonas, Peter; Thackeray, Jim; Blakey, Idriss; Whittaker, Andrew

    2017-03-01

    Out of band (OOB) radiation from the EUV source has significant implications for the performance of EUVL photoresists. Here we introduce a surface-active polymer additive, capable of partitioning to the top of the resist film during casting and annealing, to protect the underlying photoresist from OOB radiation. Copolymers were prepared using reversible addition-fragmentation chain transfer (RAFT) polymerization, and rendered surface active by chain extension with a block of fluoro-monomer. Films were prepared from the EUV resist with added surface-active Embedded Barrier Layer (EBL), and characterized using measurements of contact angles and spectroscopic ellipsometry. Finally, the lithographic performance of the resist containing the EBL was evaluated using Electron Beam Lithography exposure

  9. Soil burial biodegradation studies of palm oil-based UV-curable films

    Science.gov (United States)

    Tajau, Rida; Salleh, Mek Zah; Salleh, Nik Ghazali Nik; Abdurahman, Mohamad Norahiman; Salih, Ashraf Mohammed; Fathy, Siti Farhana; Azman, Anis Asmi; Hamidi, Nur Amira

    2016-01-01

    The palm oil-based ultraviolet (uv)-curable films were subjected to an outdoor soil burial test to investigate the biodegradation under natural environment. The films were burial in the soil experiment plot at the Nuclear Malaysia's Dengkil complex. The uv-curable films were synthesized from the epoxidized palm oil acrylated (EPOLA) resin and the polyurethane palm oil (POBUA) resin, respectively. Biodegradation tests are more specific to burial film in soil experiments for 12 months under natural conditions. The biodegradability of palm oil resin based uv-curable films were investigated and compared with the petrochemical resin based film. The films properties were compared with respect to properties of the thermal characteristic, the crystallinity, the morphology and the weight loss which are analyzed using the thermogravimetric analysis (TGA), the differential scanning calorimetry (DSC), the scanning electron microscope (SEM), an optical microscope and the weight loss of film calculation. These findings suggested that the palm oil-based uv-curable films show quite satisfactory biodegradation levels.

  10. Preparation and Characterization of UV-Curable Cyclohexanone-Formaldehyde Resin and Its Cured Film Properties

    Directory of Open Access Journals (Sweden)

    Guang Yang

    2014-01-01

    Full Text Available UV-curable cyclohexanone-formaldehyde (UVCF resin was prepared with cyclohexanone-formaldehyde (CF resin, isophorone diisocyanate (IPDI, and pentaerythritol triacrylate (PETA as base substance, bridging agent, and functional monomer, respectively. The structure of UVCF was characterized by Fourier transform infrared spectroscopy (FT-IR, 1H-nuclear magnetic resonance spectroscopy (1H-NMR, and gel permeation chromatography (GPC. The viscosity and photopolymerization behavior of the UV-curable formulations were studied. The thermal stability and mechanical properties of the cured films were also investigated. The results showed that UVCF resin was successfully prepared, the number of average molecular weight was about 2010, and its molecular weight distribution index was 2.8. With the increase of UVCF resin content, the viscosity of the UV-curable formulations increased. After exposure to UV irradiation for 230 s, the photopolymerization conversion of the UV-curable formulations was above 80%. Moreover, when the UVCF content was 60%, the formulations had high photopolymerization rate, and the cured UVCF films showed good thermal stability and mechanical properties.

  11. Treating curable sexually transmitted infections to prevent HIV in Africa - Still an effective control strategy?

    NARCIS (Netherlands)

    White, Richard G.; Orroth, Kate K.; Glynn, Judith R.; Freeman, Esther E.; Bakker, Roel; Habbema, J. Dik F.; Terris-Prestholt, Fern; Kumaranayake, Lilani; Buve, Anne; Hayes, Richard J.

    2008-01-01

    Background: Evidence regarding the effectiveness of sexually transmitted infection (STI) treatment for HIV prevention in Africa is equivocal, leading some policy makers to question whether it should continue to be promoted for HIV control. We explore whether treating curable STIs remains a cost-effe

  12. UV and EB Curable Binder Technology for Lithium Ion Batteries and UltraCapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Voelker, Gary

    2012-04-30

    the basic feasibility of using UV curing technology to produce Lithium ion battery electrodes at speeds over 200 feet per minute has been shown. A unique set of UV curable chemicals were discovered that were proven to be compatible with a Lithium ion battery environment with the adhesion qualities of PVDF.

  13. Nanoimprint lithography using TiO2-SiO2 ultraviolet curable materials

    Science.gov (United States)

    Takei, Satoshi

    2015-05-01

    Ultraviolet nanoimprint lithography has great potential for commercial device applications that are closest to production such as optical gratings, planar waveguides, photonic crystals, semiconductor, displays, solar cell panel, sensors, highbrightness LEDs, OLEDs, and optical data storage. I report and demonstrate the newly TiO2-SiO2 ultraviolet curable materials with 20-25 wt% ratio of high titanium for CF4/O2 etch selectivity using nanoimprint lithography process. The multiple structured three-dimensional micro- and nanolines patterns were observed to be successfully patterned over the large areas. The effect of titanium concentration on CF4/O2 etch selectivity with pattern transferring carbon layer imprinting time was investigated. CF4/O2 etching rate of the TiO2-SiO2 ultraviolet curable material was approximately 3.8 times lower than that of the referenced SiO2 sol-gel ultraviolet curable material. The TiO2-SiO2 ultraviolet curable material with high titanium concentration has been proved to be versatile in advanced nanofabrication.

  14. Soil burial biodegradation studies of palm oil-based UV-curable films

    Energy Technology Data Exchange (ETDEWEB)

    Tajau, Rida, E-mail: rida@nuclearmalaysia.gov.my; Salleh, Mek Zah, E-mail: mekzah@nuclearmalaysia.gov.my; Salleh, Nik Ghazali Nik, E-mail: nik-ghazali@nuclearmalaysia.gov.my; Abdurahman, Mohamad Norahiman, E-mail: iman5031@yahoo.com [Division of Radiation Processing Technology, Malaysia Nuclear Agency, Bangi, 43000 Kajang, Selangor (Malaysia); Salih, Ashraf Mohammed, E-mail: ashraf.msalih@gmail.com [Department of Radiation Processing, Sudan Atomic Energy Commission, Khartoum, 1111 Sudan (Sudan); Fathy, Siti Farhana, E-mail: farhana811@hotmail.com [Laboratory of Molecular Biomedicine, Institute of Bioscience (IBS), Universiti Putra Malaysia (UPM), 43400 UPM, Serdang, Selangor (Malaysia); Azman, Anis Asmi, E-mail: anisasmi18@gmail.com; Hamidi, Nur Amira, E-mail: amirahamidi93@yahoo.com [School of Chemical Sciences, Universiti Sains Malaysia (USM), 11800 USM, Pulau Pinang (Malaysia)

    2016-01-22

    The palm oil-based ultraviolet (uv)-curable films were subjected to an outdoor soil burial test to investigate the biodegradation under natural environment. The films were burial in the soil experiment plot at the Nuclear Malaysia’s Dengkil complex. The uv-curable films were synthesized from the epoxidized palm oil acrylated (EPOLA) resin and the polyurethane palm oil (POBUA) resin, respectively. Biodegradation tests are more specific to burial film in soil experiments for 12 months under natural conditions. The biodegradability of palm oil resin based uv-curable films were investigated and compared with the petrochemical resin based film. The films properties were compared with respect to properties of the thermal characteristic, the crystallinity, the morphology and the weight loss which are analyzed using the thermogravimetric analysis (TGA), the differential scanning calorimetry (DSC), the scanning electron microscope (SEM), an optical microscope and the weight loss of film calculation. These findings suggested that the palm oil-based uv-curable films show quite satisfactory biodegradation levels.

  15. The effect of glucose-coated gold nanoparticles on radiation bystander effect induced in MCF-7 and QUDB cell lines.

    Science.gov (United States)

    Rostami, Atefeh; Toossi, Mohammad Thaghi Bahreyni; Sazgarnia, Ameneh; Soleymanifard, Shokouhozaman

    2016-11-01

    Due to biocompatibility and relative non-toxic nature, gold nanoparticles (GNPs) have been studied widely to be employed in radiotherapy as radio-sensitizer. On the other hand, they may enhance radiation-induced bystander effect (RIBE), which causes radiation adverse effects in non-irradiated normal cells. The present study was planned to investigate the possibility of augmenting the RIBE consequence of applying glucose-coated gold nanoparticles (Glu-GNPs) to target cells. Glu-GNPs were synthesized and utilized to treat MCF7 and QUDB cells. The treated cells were irradiated with 100 kVp X-rays, and their culture media were transferred to non-irradiated bystander cells. Performing MTT cellular proliferation test and colony formation assay, percentage cell viability and survival fraction of bystander cells were determined, respectively, and were compared to control bystander cells which received culture medium from irradiated cells without Glu-GNPs. Glu-GNPs decreased the cell viability and survival fraction of QUDB bystander cells by as much as 13.2 and 11.5 %, respectively (P bystander cells. Different RIBE responses were observed in QUDB and MCF7 loaded with Glu-GNPs. Glu-GNPs increased the RIBE in QUDB cells, while they had no effects on RIBE in MCF7 cells. As opposed to QUDB cells, the RIBE in MCF7 cells did not change in the dose range of 0.5-10 Gy. Therefore, it might be a constant effect and the reason of not being increased by Glu-GNPs.

  16. 用于三维成型光固化树脂的制备%Preparation of UV curable resin for 3D printing

    Institute of Scientific and Technical Information of China (English)

    郁文汉; 胡刚华

    2013-01-01

    研发了一种三维打印成型用的光固化树脂.该树脂由不饱和聚酯树脂,丙烯酸环氧树脂,桐油酸酐,以及光引发剂、促进剂、填料等组成.该光固化树脂经紫外光照射10~30 s即可固化,其成本仅为进口产品的1/10左右,对于三维打印成型技术推广普及具有积极作用.%A UV curable resin for 3D printing was prepared. The resin consists of unsaturated polyester resin, acrylic epoxy resin, tung oil anhydride, photoinitiator, promoter and fillers etc. The UV curable resin can be cured after exposure under the UV-light radiation for 10~30 s. Its cost only about one-tenth of the import product cost, so that resin production has the positive effect on the popularization and promotion activities of 3D printing technology.

  17. Optimal spectra of the phosphor-coated white LEDs with excellent color rendering property and high luminous efficacy of radiation.

    Science.gov (United States)

    He, Guoxing; Yan, Huafeng

    2011-01-31

    A model for spectra of the phosphor-coated white LED (p-W LED) with a blue chip, a red chip, and green and yellow phosphors is presented. The optimal spectra of p-W LEDs with correlated color temperatures (CCTs) of 2700-6500 K have been obtained with a nonlinear program for maximizing luminous efficacy of radiation (LER) under conditions of both color-rendering indices (CRIs) and special CRIs of R9 strong red above 98. The simulation results show that p-W LEDs with one InGaN blue (450 nm) chip, one AlGaInP red (634 nm) chip, and green (507 nm) and yellow (580 nm) silicate phosphors can realize white lights with CRIs of about 98 and special CRIs of R9 for strong red above 98. The average of the special CRIs R9 to R12 for the four saturated colors (red, yellow, green, and blue) is above 95. R13 for the skin of women's faces at about 100, as well as LERs above 296 lm/W at CCTs of 2700-6500 K. LERs of excellent CRI p-W LEDs with one InGaN blue chip, one AlGaInP red chip, and green and yellow silicate phosphors increased by 19-49% when compared with that of excellent CRI p-W LEDs with one InGaN blue chip and green and yellow silicate phosphors, as well as red nitride phosphor.

  18. Effects of radiation on fixation of non-cemented porous-coated implants in a canine model

    Energy Technology Data Exchange (ETDEWEB)

    Sumner, D.R.; Turner, T.M.; Pierson, R.H.; Kienapfel, H.; Urban, R.M.; Liebner, E.J.; Galante, J.O. (Rush-Presbyterian-St. Luke' s Medical Center, Chicago, IL (USA))

    1990-12-01

    A non-weight-bearing porous-coated rod was implanted bilaterally in the proximal part of the humerus in thirty-five adult male mongrel dogs. In all of the animals, one limb was treated with radiation and the opposite limb served as the control. In twenty-one animals, the dose was 1000 centigrays (rads) and in fourteen, it was 500 centigrays. The strength of fixation and the volume fraction of ingrowth of bone were determined two, four, and eight weeks after the operation in the group that received 1000 centigrays and two and four weeks after the operation in the group that received 500 centigrays. Treatment with 500 centigrays had no significant effect on the strength of fixation or the amount of ingrowth of bone. In contrast, at two weeks, treatment with 1000 centigrays had reduced the strength of fixation to 50 per cent of the control value (p less than 0.01), although, at four and eight weeks, the strength of fixation was not significantly different than that in the control limb. The amount of ingrowth of bone in the irradiated limb was significantly reduced at two weeks (30 per cent of the control value) (p less than 0.01), four weeks (70 per cent of the control value) (p less than 0.05), and eight weeks (56 per cent of the control value) (p less than 0.05).

  19. Effects of radiation on fixation of non-cemented porous-coated implants in a canine model.

    Science.gov (United States)

    Sumner, D R; Turner, T M; Pierson, R H; Kienapfel, H; Urban, R M; Liebner, E J; Galante, J O

    1990-12-01

    A non-weight-bearing porous-coated rod was implanted bilaterally in the proximal part of the humerus in thirty-five adult male mongrel dogs. In all of the animals, one limb was treated with radiation and the opposite limb served as the control. In twenty-one animals, the dose was 1000 centigrays (rads) and in fourteen, it was 500 centigrays. The strength of fixation and the volume fraction of ingrowth of bone were determined two, four, and eight weeks after the operation in the group that received 1000 centigrays and two and four weeks after the operation in the group that received 500 centigrays. Treatment with 500 centigrays had no significant effect on the strength of fixation or the amount of ingrowth of bone. In contrast, at two weeks, treatment with 1000 centigrays had reduced the strength of fixation to 50 per cent of the control value (p less than 0.01), although, at four and eight weeks, the strength of fixation was not significantly different than that in the control limb. The amount of ingrowth of bone in the irradiated limb was significantly reduced at two weeks (30 per cent of the control value) (p less than 0.01), four weeks (70 per cent of the control value) (p less than 0.05), and eight weeks (56 per cent of the control value) (p less than 0.05).

  20. [Effectiveness of chemoradiotherapy for a patient with local recurrence of advanced gastric cancer followed by curable gastrectomy].

    Science.gov (United States)

    Natsume, Soichiro; Iwasaki, Yoshiaki; Yajima, Kazuhito; Yuu, Ken; Oohinata, Ryouki; Ishiyama, Satoshi; Takahashi, Keiichi; Maeda, Yoshiharu

    2014-11-01

    We report here the effectiveness of chemoradiotherapy for a patient with local recurrence followed by curable gastrectomy. A 57-year-old man presented with a history of total gastrectomy with distal pancreatectomy and splenectomy, D2 lymphadenectomy, and Roux-en-Y reconstruction for advanced gastric cancer arising from the cardia. Esophageal intramural metastasis and lymph node metastasis around the right recurrent nerve were detected by chest-abdominal computed tomography and gastrointestinal endoscopy 27 months after the initial gastrectomy. Stable disease was achieved following 7 courses of chemotherapy using S-1 plus CDDP. Concurrent chemoradiotherapy including administration of S-1 and radiation of total 50 Gy (2 Gy/25 Fr) was selected for local tumor control. The patient was not able to eat solid food because of esophageal stenosis from regrowth of intramural metastasis of the esophagus 60 months after the chemotherapy. A WallFlex™ Duodenal Stent was placed to improve the dysphagia 67 months after chemotherapy. The patient died from recurrence of gastric cancer 69 months after completion of the initial chemotherapy and 2 months after the stent insertion.

  1. Investigation of ultraviolet curable waterborne polyurethane acrylate dispersion based on hydroxyl-terminated polybutadiene

    Institute of Scientific and Technical Information of China (English)

    NIU Zhenbin; ZHANG Xingyuan; DAI Jiabing; ZHANG Heping

    2007-01-01

    A new kind of ultraviolet (UV) curable waterborne polyurethane acrylate dispersion was synthesized based on hydroxyl-terminated polybutadiene (HTPB),poly(propylene glycol) (PPG),isophorene diisocyanate (IPDI),2-hydroxy ethyl acrylate (HEA) and dimethylol propionic acid (DMPA) after neutralizing by triethylamine (TEA).2-Hydroxy- 1-[4-(2-hydroxyethoxy) phenyl]-2-methyl-1-propanone (Irgacure 2959) was used as a photoinitiator and deionized water as a diluent.Fourier transform infrared (FTIR) analysis was used to identify the chain structure of the UV-curable polyurethane prepolymer based on HTPB and the curing process.Effects of relative content of HTPB and PPG on emulsion stability,resistance to water and ethanol,thermal stability,compatibility of soft and hard segment,as well as the mechanical property of the cured film were investigated.

  2. The Biomineralization of a Bioactive Glass-Incorporated Light-Curable Pulp Capping Material Using Human Dental Pulp Stem Cells

    OpenAIRE

    Soo-Kyung Jun; Jung-Hwan Lee; Hae-Hyoung Lee

    2017-01-01

    The aim of this study was to investigate the biomineralization of a newly introduced bioactive glass-incorporated light-curable pulp capping material using human dental pulp stem cells (hDPSCs). The product (Bioactive® [BA]) was compared with a conventional calcium hydroxide-incorporated (Dycal [DC]) and a light-curable (Theracal® [TC]) counterpart. Eluates from set specimens were used for investigating the cytotoxicity and biomineralization ability, determined by alkaline phosphatase (ALP) a...

  3. Case and partnership reproduction numbers for a curable sexually transmitted infection.

    Science.gov (United States)

    Heijne, Janneke C M; Herzog, Sereina A; Althaus, Christian L; Low, Nicola; Kretzschmar, Mirjam

    2013-08-21

    Sexually transmitted infections (STIs) are, by definition, transmitted between sexual partners. For curable STIs an infected index case can potentially re-infect the same partner multiple times. Thus, R0, the average number of secondary infections one typical infected individual will produce during his or her infectious period is not necessarily the same as the average number of secondary cases (infected persons). Here we introduce the new concept of the case reproduction number (Rc). In addition, we define the partnership reproduction number (Rp) as the average number of secondary partnerships consisting of two infected individuals one typical infected individual will produce over his or her infectious lifetime. Rp takes into account clearance and re-infection within partnerships, which results in a prolongation of the duration of the infectious period. The two new reproduction numbers were derived for a deterministic pair model with serial monogamous partnerships using infection parameters for Chlamydia trachomatis, an example of a curable STI. We showed that re-infection within partnerships means that curable STIs can be sustained endemically even when the average number of secondary cases a person produces during his or her infectious period is below one. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Characterization of curing behavior of UV-curable LSR for LED embedded injection mold

    Science.gov (United States)

    Tae, Joon-Sung; Yim, Kyung-Gyu; Rhee, Byung-Ohk; Kwak, Jae B.

    2016-11-01

    For many applications, liquid silicone rubber (LSR) injection molding is widely used for their great design flexibility and high productivity. In particular, a sealing part for a mobile device such as smartphone and watch has been produced by injection molding. While thermally curable LSR causes deformation problem due to a high mold temperature, UV-curable LSR can be molded at room temperature, which has advantages for over-molding with inserts of temperature-sensitive materials. Ultraviolet light-emitting diodes (UV LEDs) have advantages such as a longer service life, a lower heat dissipation, and smaller size to equip into the mold than conventional halogen or mercury UV lamps. In this work, rheological behavior of UV-curable LSR during curing process was analyzed by UV LEDs available in the market. UV-LEDs of various wave lengths and intensities were tested. The steady shear test was applied to find the starting time of curing and the SAOS was applied to find the ending time of curing to estimate processing time. In addition, the hardness change with irradiation energy was compared with the rheological data to confirm the reliability of the rheological test.

  5. Chronic TiO{sub 2} nanoparticle exposure to a benthic organism, Hyalella azteca: impact of solar UV radiation and material surface coatings on toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Wallis, Lindsay K. [Office of Research and Development, Mid-Continent Ecology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Duluth, MN, 55804 (United States); Diamond, Stephen A. [Nanosafe Inc., Blacksburg, VA, 24060 (United States); Ma, Hongbo [University of Wisconsin-Milwaukee, Zilber School of Public Health, Milwaukee, WI, 53211 (United States); Hoff, Dale J. [Office of Research and Development, Mid-Continent Ecology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Duluth, MN, 55804 (United States); Al-Abed, Souhail R. [National Risk Management Research Laboratory, U.S. Environmental Protection Agency, Cincinnati, OH 45268 (United States); Li, Shibin, E-mail: lishibinepa@gmail.com [Office of Research and Development, Mid-Continent Ecology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Duluth, MN, 55804 (United States)

    2014-11-15

    There is limited information on the chronic effects of nanomaterials to benthic organisms, as well as environmental mitigating factors that might influence this toxicity. The present study aimed to fill these data gaps by examining various growth endpoints (weight gain, instantaneous growth rate, and total protein content) for up to a 21 d sediment exposure of TiO{sub 2} nanoparticles (nano-TiO{sub 2}) to a representative benthic species, Hyalella azteca. An uncoated standard, P25, and an Al(OH){sub 3} coated nano-TiO{sub 2} used in commercial products were added to sediment at 20 mg/L or 100 mg/L Under test conditions, UV exposure alone was shown to be a greater cause of toxicity than even these high levels of nano-TiO{sub 2} exposure, indicating that different hazards need to be addressed in toxicity testing scenarios. In addition, this study showed the effectiveness of a surface coating on the decreased photoactivity of the material, as the addition of an Al(OH){sub 3} coating showed a dramatic decrease in reactive oxygen species (ROS) production. However, this reduced photoactivity was found to be partially restored when the coating had been degraded, leading to the need for future toxicity tests which examine the implications of weathering events on particle surface coatings. - Highlights: • Chronic toxicity of nano-TiO{sub 2} to a benthic organism (Hyalella azteca) was examined. • Phototoxicity was investigated through exposure of solar simulated radiation (SSR). • The degradation of a surface coating resulted in an increase in photoactivity. • In this testing scenario, UV had a larger impact than chemical exposure in toxicity.

  6. Structural changes of polymer-coated microgranules and excipients on tableting investigated by microtomography using synchrotron X-ray radiation.

    Science.gov (United States)

    Kajihara, Ryusuke; Noguchi, Shuji; Iwao, Yasunori; Suzuki, Yoshio; Terada, Yasuko; Uesugi, Kentaro; Itai, Shigeru

    2015-03-15

    Multiple-unit tablets consisting of polymer-coated microgranules and excipients have a number of advantageous pharmaceutical properties. Polymer-coated microgranules are known to often lose their functionality because of damage to the polymer coating caused by tableting, and the mechanism of polymer coating damage as well as the structural changes of excipients upon tableting had been investigated but without in-situ visualization and quantitative analysis. To elucidate the mechanism of coating damage, the internal structures of multiple-unit tablets were investigated by X-ray computed microtomography using synchrotron X-rays. Cross sectional images of the tablets with sub-micron spatial resolution clearly revealed that void spaces remained around the compressed excipient particles in the tablets containing an excipient composed of cellulose and lactose (Cellactose(®) 80), whereas much smaller void spaces remained in the tablets containing an excipient made of sorbitol (Parteck(®) SI 150). The relationships between the void spaces and the physical properties of the tablets such as hardness and disintegration were investigated. Damage to the polymer coating in tablets was found mainly where polymer-coated microgranules were in direct contact with each other in both types of tablets, which could be attributed to the difference in hardness of excipient particles and the core of the polymer-coated microgranules. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Achieving Stable Radiation Pressure Acceleration of Heavy Ions via Successive Electron Replenishment from Ionization of a High-Z Material Coating

    Science.gov (United States)

    Shen, X. F.; Qiao, B.; Zhang, H.; Kar, S.; Zhou, C. T.; Chang, H. X.; Borghesi, M.; He, X. T.

    2017-05-01

    A method to achieve stable radiation pressure acceleration (RPA) of heavy ions from laser-irradiated ultrathin foils is proposed, where a high-Z material coating in front is used. The coated high-Z material, acting as a moving electron repository, continuously replenishes the accelerating heavy ion foil with comoving electrons in the light-sail acceleration stage due to its successive ionization under laser fields with Gaussian temporal profile. As a result, the detrimental effects such as foil deformation and electron loss induced by the Rayleigh-Taylor-like and other instabilities in RPA are significantly offset and suppressed so that stable acceleration of heavy ions are maintained. Particle-in-cell simulations show that a monoenergetic Al13 + beam with peak energy 3.8 GeV and particle number 1 010 (charge >20 nC ) can be obtained at intensity 1 022 W /cm2 .

  8. Radiation dose rate affects the radiosensitization of MCF-7 and HeLa cell lines to X-rays induced by dextran-coated iron oxide nanoparticles.

    Science.gov (United States)

    Khoshgard, Karim; Kiani, Parvaneh; Haghparast, Abbas; Hosseinzadeh, Leila; Eivazi, Mohammad Taghi

    2017-08-01

    The aim of radiotherapy is to deliver lethal damage to cancerous tissue while preserving adjacent normal tissues. Radiation absorbed dose of the tumoral cells can increase when high atomic nanoparticles are present in them during irradiation. Also, the dose rate is an important aspect in radiation effects that determines the biological results of a given dose. This in vitro study investigated the dose-rate effect on the induced radiosensitivity by dextran-coated iron oxide in cancer cells. HeLa and MCF-7 cells were cultured in vitro and incubated with different concentrations of dextran-coated iron oxide nanoparticles. They were then irradiated with 6 MV photons at dose rates of 43, 185 and 370 cGy/min. The MTT test was used to obtain the cells' survival after 48 h of irradiations. Incubating the cells with the nanoparticles at concentrations of 10, 40 and 80 μg/ml showed no significant cytotoxicity effect. Dextran-coated iron oxide nanoparticles showed more radiosensitivity effect by increasing the dose rate and nanoparticles concentration. Radiosensitization enhancement factors of MCF-7 and HeLa cells at a dose-rate of 370 cGy/min and nanoparticles' concentration of 80 μg/ml were 1.21 ± 0.06 and 1.19 ± 0.04, respectively. Increasing the dose rate of 6 MV photons irradiation in MCF-7 and HeLa cells increases the radiosensitization induced by the dextran-coated iron nanoparticles in these cells.

  9. 等离子喷涂B4C涂层的抗辐射性能研究%Anti-radiation behavior of plasma sprayed boron carbide coatings

    Institute of Scientific and Technical Information of China (English)

    李龙根; 徐志勇; 钱浩

    2009-01-01

    目的 研究用等离子技术喷涂的碳化硼(B4C)涂层的抗辐射能力.方法 将0.1 mm厚度B4C涂在16号锰钢上,研究它对加速器产生的6、10、15 MV高能射线,6、9、12、15 MeV高能电子线,60Co γ线和快中子辐射的防护作用.同时将0.1 mm B4C涂在纸板上,研究它对深部X线机的X线辐射的防护作用.结果 等离子喷涂制备B4C涂层对高能X线和60Co γ线没有防护作用.对电子线有一定防护作用,且随深度的增加有增大趋势,但作用不大.对快中子有较大防护作用.对深部X线机X线有防护作用,防护能力较强.0.1 mm厚的涂层就可带来15%的衰减.结论 用等离子技术喷涂的B4C涂层可在医学领域用来防护千伏级射线.%Objective To study anti-radiation behavior of plasma sprayed boron carbide coatings. Methods The anti-radiation capacity of 16Mn steel which was coated with 0.1 mm plasma sprayed boron carbide were studied. The irradiation beams were 6,10,15 MY X-ray and 6,9,12,15 MeV electron emitted by accelerator, X-ray emitted by 60Co machine,fast neutron, and X-ray emitted by kilovoltage X-ray ma-chine. Results Anti-radiation capacity of plasma sprayed boron carbide coatings was not found for X-ray beams emitted by accelerator and 60Co machine. For electron beams,the anti-radiation capacity were found. The deeper of location, the stronger was anti-radiation. However, the anti-radiation capacity was not good. For fast neutron,the anti-radiation capacity was good. For X-ray emitted by kilovoltage X-ray machine,the anti-radiation was good,and only 0.1 nun plasma sprayed boron carbide had 15% attenuation. Conclusions The plasma sprayed boron carbide coatings have the anti-radiation capacity for X-ray emitted by kilovoltage X-ray machine in medical field.

  10. Antimicrobial and biological activity of leachate from light curable pulp capping materials.

    Science.gov (United States)

    Arias-Moliz, Maria Teresa; Farrugia, Cher; Lung, Christie Y K; Wismayer, Pierre Schembri; Camilleri, Josette

    2017-09-01

    Characterization of a number of pulp capping materials and assessment of the leachate for elemental composition, antimicrobial activity and cell proliferation and expression. Three experimental light curable pulp-capping materials, Theracal and Biodentine were characterized by scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction. The elemental composition of the leachate formed after 24h was assessed by inductively coupled plasma (ICP). The antimicrobial activity of the leachate was determined by the minimum inhibitory concentration (MIC) against multispecies suspensions of Streptococcus mutans ATCC 25175, Streptococcus gordonii ATCC 33478 and Streptococcus sobrinus ATCC 33399. Cell proliferation and cell metabolic function over the material leachate was assessed by an indirect contact test using 3-(4,5 dimethylthiazolyl-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The hydration behavior of the test materials varied with Biodentine being the most reactive and releasing the highest amount of calcium ions in solution. All materials tested except the unfilled resin exhibited depletion of phosphate ions from the solution indicating interaction of the materials with the media. Regardless the different material characteristics, there was a similar antimicrobial activity and cellular activity. All the materials exhibited no antimicrobial activity and were initially cytotoxic with cell metabolic function improving after 3days. The development of light curable tricalcium silicate-based pulp capping materials is important to improve the bonding to the final resin restoration. Testing of both antimicrobial activity and biological behavior is critical for material development. The experimental light curable materials exhibited promising biological properties but require further development to enhance the antimicrobial characteristics. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Visible Light Curable Restorative Composites for Dental Applications Based on Epoxy Monomer

    Directory of Open Access Journals (Sweden)

    Alessandra Vitale

    2014-01-01

    Full Text Available A cationic photo-curable cycloaliphatic epoxy resin has been investigated as reactive monomer in blue light crosslinking process. We have demonstrated that camphorquinone is able to abstract labile hydrogen from the epoxy monomer, giving rise to the formation of carbon-centered radicals that are oxidized by the onium salt; a complete epoxy group conversion was reached after 50 s of irradiation. The presence of water up to 1 wt% was tolerated without any important detrimental effect on the kinetics of light-curing. The presence of the inorganic filler up to 65 wt% did not significantly influence the curing process.

  12. Actual expertise issues of professional suitability of patients with highly curable heart arrhythmias

    Directory of Open Access Journals (Sweden)

    Krainyukov P.E.

    2015-09-01

    Conclusion. The concept of highly curable heart arrhythmia is introduced. A significant proportion of patients with these arrhythmias are young and of working age, they do not have organic heart disease. High efficiency of RFA for paroxysmal disorders of rhythm, small percentage of complications and recurrences, fast professional and social rehabilitation of these patients allow to revise the existing categories of fitness in respect of persons who underwent RFA. Follow-up medical examination including endo-EFI and subsequent medical examination to determine the category of fitness for military service should be carried out not earlier than 3 months after RFA.

  13. Micromechanical radiation dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Thundat, T.; Sharp, S.L.; Fisher, W.G.; Warmack, R.J.; Wachter, E.A. (Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6123 (United States))

    1995-03-20

    We demonstrate the use of microcantilevers coated with ultraviolet cross-linking polymers as optical radiation dosimeters. Upon exposure to radiation, a treated cantilever bends due to stress and its resonance frequency increases due to stiffening. These phenomena can be used to develop sensitive radiation dosimeters which respond to radiation affecting the mechanical properties of the selected coating.

  14. Radiation controlling reversible window

    Energy Technology Data Exchange (ETDEWEB)

    Gell, H.A. Jr.

    1980-01-01

    A coated glass glazing system is presented including a transparent glass substrate having one surface coated with a radiation absorptive film which is overcoated with a radiation reflective film by a technique which renders the radiation reflective film radiation absorptive at the surface contracting the radiating absorptive film. The coated glass system is used as glazing for storm windows which are adapted to be reversible so that the radiation reflective surface may be exposed to the outside of the dwelling during the warm seasons to prevent excessive solar radiation from entering a dwelling and reversed during cold seasons to absorb solar radiation and utilize it to aid in keeping the dwelling interior warm.

  15. Gamma-radiation synthesis of silk fibroin coated CdSe quantum dots and their biocompatibility and photostability in living cells.

    Science.gov (United States)

    Chang, Shu-Quan; Dai, Yao-Dong; Kang, Bin; Han, Wei; Chen, Da

    2009-10-01

    Silk fibroin coated CdSe quantum dots (SF-CdSe QDs) were successfully synthesized via a one-step gamma-radiation route in an aqueous system at room temperature. The as prepared products were characterized by transmission electron microscope (TEM), energy dispersion spectrum (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-vis) and photoluminescence spectrum (PL). The SF-CdSe QDs were about 5 nm in diameter and exhibited excellent water-solubility and photoluminescence properties. The cellular distribution, photostability and cytotoxicity of SF-CdSe QDs with different amount of SF coatings were also investigated by laser scanning confocal microscope (LSCM) and MTT assays in human pancreatic carcinoma (PANC-1) cells. All the results reveal that these QDs could be easily internalized by cells and localized in cytoplasm around nuclei. Moreover, SF-CdSe QDs were proved to be low cytotoxicity (the concentration of QDs CdSe QDs might have many potential applications in tumor imaging and therapy. And the synthesis strategy could be easily extended to fabrication of other nanoparticles coated with silk fibroin.

  16. [Frequency of curable sexually transmitted infections among registered female sex-workers in Ankara City].

    Science.gov (United States)

    Zarakolu, Pinar; Alp, Sehnaz; Yağci, Server

    2010-01-01

    Sex-workers are considered as the high-risk population for sexually transmitted infections (STIs). Early diagnosis and treatment of curable STIs in this high-risk group have crucial importance in STI control and prevention of complications and transmission of infection. In this study, 146 registered female sex-workers in Ankara city were screened with rapid diagnostic tests (RDT) for causative agents of curable STIs such as, Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis and Treponema pallidum. To identify gonorrhoea, Gram stained endocervical smears were examined microscopically for the presence of gram-negative intracellular diplococci. For the diagnosis of chlamydial infection, an optic immunoassay (OIA) (Chlamydia OIA, Biostar, USA) as a RDT was performed by using endocervical specimens. For the detection of T. vaginalis, direct smears of vaginal swabs were examined for the presence of motile trophozoites first directly and after being cultured in Diamond's media for 24-48 hours of incubation. Syphilis was screened in the serum specimens by RPR (Omega, UK) test. There was no positive test results for gonorrhoea and syphilis however, the frequency of C. trachomatis and T. vaginalis in the study population was 1.4% and 0.7%, respectively. To provide comprehensive policies and optimal control strategies, a reliable source of data about the frequency and spectrum of STIs among high-risk populations and optimized effective screening programmes are required.

  17. Preparation and property of UV-curable polyurethane acrylate film filled with cationic surfactant treated graphene

    Science.gov (United States)

    Xu, Jinghong; Cai, Xia; Shen, Fenglei

    2016-08-01

    The preparation of nanocomposite films composed of UV-curable polyurethane acrylate (PUA) and modified graphene were demonstrated in this paper. Cetyl trimethyl ammonium bromide modified graphene (CTAB-G) was prepared via intercalation of cationic surfactant and subsequently incorporated into PUA by UV curing technology. Fourier transform infrared spectra, wide-angle X-ray diffraction, scanning electron microscopy and transmission electron microscopy were used to characterize the structure and morphology of CTAB-G, as well as CTAB-G/PUA nanocomposite films. The results revealed that the CTAB-G sheets were layer-by-layer structure and dispersed uniformly in PUA matrix. Thermal gravimetric analysis showed that the thermal stabilities of UV-curable PUA nanocomposite films in this work were much higher than that of PUA nanocomposites previously reported. Dynamic mechanical analysis indicated that the dynamic mechanical properties of nanocomposite films were greatly enhanced in the presence of modified graphene sheets. In addition, the CTAB-G/PUA nanocomposite films exhibited improved dielectric properties and electrical conductivities compared with the pure PUA.

  18. Study of UV-curable composite resin of transfer tray for orthodontics

    Institute of Scientific and Technical Information of China (English)

    Lin YANG; Wei WU; Bao-hua XU; Pei-zeng JIA; Jun NIE

    2008-01-01

    Objectives: the aim of this study was to invest-igate the properties of UV-curable composite resin of transfer tray for indirect bonding system of the lingual brackets. Methods: the conversion of double-bond in the different concentration of UV-initiator was monitored by real time infrared (RTIR). The three-point flexure strength was measured by a universal testing machine. The storage modulus, loss modulus, and loss factor (tan delta) of the resin were measured by a Dynamic Mechanical Analyzer. The cytotoxicity of composite resin was evaluated by the agar covering test. Results: the dou-ble bond conversion exceeded 70% at [benzophe-none] = 0.7 wt.%, [Ethyl 4-dimethylaminobenzoate] = 0.7 wt.% and [2-Hydroxy-2-methyl-1-phenyl propa-non] = 1 wt.%. The mean value of flexural strength came to 122 MPa. The value of storage modulus was 1.04 × 109 MPa at 23℃. The glass transition temperature was 142℃. The toxicity grade was zero at 2 h and one at 24 h. Conclusions: in the preliminary evaluations, we indi-cated that the UV-curable composite resin of transfer tray could satisfy the clinical requirements.

  19. 低发射率伪装涂层辐射特性影响因素的理论分析%Theoretical Analysis of Effects on Radiation of Camouflage Coating

    Institute of Scientific and Technical Information of China (English)

    陈都; 曹巨辉; 潘玉龙; 何超

    2016-01-01

    Radiation characteristic of the coating directly affects its infrared feature. In order to obtain the factors influencing the radiation characteristic of camouflage coating, a model of coating radiation characteristic based on Kubelka⁃Munk theory was an⁃alyzed in depth resulting in the mathematical expression of apparent emissivity and apparent reflectivity of camouflage coating. On this basis, a detailed discussion was held on the way and the extent coating parameters such as film thickness, volume fraction of fill⁃er material and particle size may influence the radiation characteristic of low emissivity coating. Conclusions can be not only applied in analyzing camouflage coating with low emissivity but also has some significance in design of some other functional coatings.%涂层的辐射特性直接影响其红外性能。为了分析伪装涂层辐射特性的影响因素,对基于Kubelka⁃Munk理论的涂层辐射特性模型进行了深入分析,得到了涂层表观发射率和表观反射率的数学表达式。在此基础上,利用数学方法详细讨论了涂层厚度、填料粒子体积分数和粒子尺寸对低发射率伪装涂层辐射特性的影响方式和影响程度。结论不仅适用于低发射率伪装涂层,对一些其他功能性伪装涂层的设计也有一定的指导意义。

  20. The Radar Cross Section of a Two Dimensional Dielectric Coated Cylinder Using On-Surface Radiation Conditions

    Science.gov (United States)

    1988-12-01

    the trigonometry identity 1 + cosO = 2 cos 2, the expression for the RCS reduces to: (irkb) 2 1 cos 2 +G2 3 = k [ 2kb 2 (6) ] J0 (z) + G J1(Z...Handbook. Plenum Press, New York. 1970. Tang, Charles C. H. "Backscattering from Dielectric-Coated Infinite Cylindrical Obstacles ," Journal of Applied

  1. Radiation Stability of Triple Coatings Based on Transition-Metal Nitrides Under Irradiation By Alpha Particles and Argon Ions

    Science.gov (United States)

    Potekaev, A. I.; Kislitsyn, S. B.; Uglov, V. V.; Klopotov, A. A.; Gorlachev, I. D.; Klopotov, V. D.; Grinkevich, L. S.

    2016-05-01

    The data on the influence of irradiation of (Ti, Cr)N1-x coatings by helium and argon ions on their surface structure are presented. The (Ti, Cr)N1-x coatings 50-300 nm in thickness were formed on carbon steel substrates by vacuum-arc deposition. Irradiation of the coated specimens was performed in a DC-60 heavy-ion accelerator by low-energy 4He+1, 4He+2 and 40Ar5+ ions and high-energy 40Ar5+ ions up to the fluence 1.0·1017 ion/cm2 at the irradiation temperature not higher than 150°C. It is shown that irradiation of the (Ti, Cr)N1-x coating surface by 4He+1, 4He+2 and 40Ar5+ ions with the energy 20 keV/charge does not give rise to any noticeable structural changes nor any surface blistering, while its irradiation by 40Ar5+ ions with the energy 1.50 MeV/amu causes blistering.

  2. An analytic solution of the transient behavior of backscattering thermal protective coatings exposed to combined radiative and convective heating

    Science.gov (United States)

    Cornelison, Charles J.; Howe, John T.

    1991-01-01

    An analytic solution of the material response to combined radiative and convective heating is presented. The solution includes the equations of radiative transfer (within the material), coupled to a transient energy equation which contains both radiative and convective terms. The analysis allows for unlimited spectral detail, but assumes that within the range of applicability, the various material properties do not vary significantly with temperature. Also, to facilitate development of the analytic solution, it is assumed that scattering within the material dominates absorption, and the material exposed surface does not ablate. The exposed surface boundary condition includes convective heating and spectral radiation, some of which is absorbed by the surface and some which penetrates the surface.

  3. Investigation of Ultraviolet Light Curable Polysilsesquioxane Gate Dielectric Layers for Pentacene Thin Film Transistors.

    Science.gov (United States)

    Shibao, Hideto; Nakahara, Yoshio; Uno, Kazuyuki; Tanaka, Ichiro

    2016-04-01

    Polysilsesquioxane (PSQ) comprising 3-methacryloxypropyl groups was investigated as an ultraviolet (UV)-light curable gate dielectric-material for pentacene thin film transistors (TFTs). The surface of UV-light cured PSQ films was smoother than that of thermally cured ones, and the pentacene layers deposited on the UV-Iight cured PSQ films consisted of larger grains. However, carrier mobility of the TFTs using the UV-light cured PSQ films was lower than that of the TFTs using the thermally cured ones. It was shown that the cross-linker molecules, which were only added to the UV-light cured PSQ films, worked as a major mobility-limiting factor for the TFTs.

  4. Rho GTPases as pathogen targets: Focus on curable sexually transmitted infections.

    Science.gov (United States)

    Quintero, Cristián A; Tudela, Julián Gambarte; Damiani, María T

    2015-01-01

    Pathogens have evolved highly specialized mechanisms to infect hosts. Several microorganisms modulate the eukaryotic cell surface to facilitate their engulfment. Once internalized, they hijack the molecular machinery of the infected cell for their own benefit. At different stages of phagocytosis, particularly during invasion, certain pathogens manipulate pathways governed by small GTPases. In this review, we focus on the role of Rho proteins on curable, sexually transmitted infections caused by Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis and Treponema pallidum. Despite the high, worldwide frequencies of these sexually-transmitted diseases, very little is known about the strategies developed by these microorganisms to usurp key eukaryotic proteins that control intracellular signaling and actin dynamics. Improved knowledge of these molecular mechanisms will contribute to the elucidation of how these clinically important pathogens manipulate intracellular processes and parasitize their hosts.

  5. Rho GTPases as pathogen targets: Focus on curable sexually transmitted infections

    Science.gov (United States)

    Quintero, Cristián A; Tudela, Julián Gambarte; Damiani, María T

    2015-01-01

    Pathogens have evolved highly specialized mechanisms to infect hosts. Several microorganisms modulate the eukaryotic cell surface to facilitate their engulfment. Once internalized, they hijack the molecular machinery of the infected cell for their own benefit. At different stages of phagocytosis, particularly during invasion, certain pathogens manipulate pathways governed by small GTPases. In this review, we focus on the role of Rho proteins on curable, sexually transmitted infections caused by Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis and Treponema pallidum. Despite the high, worldwide frequencies of these sexually-transmitted diseases, very little is known about the strategies developed by these microorganisms to usurp key eukaryotic proteins that control intracellular signaling and actin dynamics. Improved knowledge of these molecular mechanisms will contribute to the elucidation of how these clinically important pathogens manipulate intracellular processes and parasitize their hosts. PMID:26023809

  6. Preparation and characterization of a novel UV-curable plastic scintillator

    Science.gov (United States)

    Zhu, Jun; Ding, Yunyu; Zhu, Jiayi; Qi, Di; Su, Ming; Xu, Yewei; Bi, Yutie; Lin, Runxiong; Zhang, Lin

    2016-05-01

    A novel UV-curable plastic scintillator was first prepared by using the technology of photosensitivity rapid prototyping. It used the copolymer of 621A-80, TPGDA and styrene as the matrix doped with PPO and POPOP. Its fluorescence spectra displayed a maximum emission wavelength at 428 nm. The light yield of the plastic scintillator was approximately 7.1% of anthracene on the basis of a comparison with the commercially available scintillator (ST-401). The as-prepared plastic scintillator also displayed a fast scintillation decay. Its decay time is 2.6 ns approximately. Importantly, through the technology of photosensitivity rapid prototyping, the plastic scintillator could be prepared in a short period of time at low temperature. What's more, this preparation method provides the possibility of combining the plastic scintillator with 3D printing technology, and then the applications of the plastic scintillator may be expanded greatly.

  7. Preparation and characterization of a novel UV-curable plastic scintillator

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jun [Engineering Research Center of High Performance Polymer and Molding Technology, Ministry of Education, Qingdao University of Science and Technology, Qingdao 266042 (China); Joint Laboratory for Extreme Conditions Matter Properties, Southwest University of Science and Technology and Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621010 (China); Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); Ding, Yunyu [Engineering Research Center of High Performance Polymer and Molding Technology, Ministry of Education, Qingdao University of Science and Technology, Qingdao 266042 (China); Zhu, Jiayi [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); Qi, Di [Engineering Research Center of High Performance Polymer and Molding Technology, Ministry of Education, Qingdao University of Science and Technology, Qingdao 266042 (China); Su, Ming [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); Xu, Yewei; Bi, Yutie [Joint Laboratory for Extreme Conditions Matter Properties, Southwest University of Science and Technology and Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621010 (China); Lin, Runxiong, E-mail: qdlrx@qust.edu.cn [Engineering Research Center of High Performance Polymer and Molding Technology, Ministry of Education, Qingdao University of Science and Technology, Qingdao 266042 (China); Zhang, Lin, E-mail: zhlmy@sina.com [Joint Laboratory for Extreme Conditions Matter Properties, Southwest University of Science and Technology and Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621010 (China); Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China)

    2016-05-01

    A novel UV-curable plastic scintillator was first prepared by using the technology of photosensitivity rapid prototyping. It used the copolymer of 621A-80, TPGDA and styrene as the matrix doped with PPO and POPOP. Its fluorescence spectra displayed a maximum emission wavelength at 428 nm. The light yield of the plastic scintillator was approximately 7.1% of anthracene on the basis of a comparison with the commercially available scintillator (ST-401). The as-prepared plastic scintillator also displayed a fast scintillation decay. Its decay time is 2.6 ns approximately. Importantly, through the technology of photosensitivity rapid prototyping, the plastic scintillator could be prepared in a short period of time at low temperature. What's more, this preparation method provides the possibility of combining the plastic scintillator with 3D printing technology, and then the applications of the plastic scintillator may be expanded greatly.

  8. Preparation and property of UV-curable polyurethane acrylate film filled with cationic surfactant treated graphene

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jinghong; Cai, Xia; Shen, Fenglei, E-mail: shenfenglei@suda.edu.cn

    2016-08-30

    Highlights: • The non-covalent modification of graphene maintains the intrinsic structure of graphene compared with the covalent functionalization of graphene. • The initial degradation temperature of nanocomposite film increases by 57 °C which is much higher than that of PUA nanocomposite previously reported. • The nanocomposite film exhibits improved dielectric property and electrical conductivity. • The outstanding performance of CTAB-G/PUA films will open up enormous opportunities for applications in various regions such as high temperature or electrical field. - Abstract: The preparation of nanocomposite films composed of UV-curable polyurethane acrylate (PUA) and modified graphene were demonstrated in this paper. Cetyl trimethyl ammonium bromide modified graphene (CTAB-G) was prepared via intercalation of cationic surfactant and subsequently incorporated into PUA by UV curing technology. Fourier transform infrared spectra, wide-angle X-ray diffraction, scanning electron microscopy and transmission electron microscopy were used to characterize the structure and morphology of CTAB-G, as well as CTAB-G/PUA nanocomposite films. The results revealed that the CTAB-G sheets were layer-by-layer structure and dispersed uniformly in PUA matrix. Thermal gravimetric analysis showed that the thermal stabilities of UV-curable PUA nanocomposite films in this work were much higher than that of PUA nanocomposites previously reported. Dynamic mechanical analysis indicated that the dynamic mechanical properties of nanocomposite films were greatly enhanced in the presence of modified graphene sheets. In addition, the CTAB-G/PUA nanocomposite films exhibited improved dielectric properties and electrical conductivities compared with the pure PUA.

  9. A novel hohlraum with ultrathin depleted-uranium-nitride coating layer for low hard x-ray emission and high radiation temperature

    CERN Document Server

    Guo, Liang; Xing, Peifeng; Li, Sanwei; Yi, Taimin; Kuang, Longyu; Li, Zhichao; Li, Renguo; Wu, Zheqing; Jing, Longfei; Zhang, Wenhai; Zhan, Xiayu; Yang, Dong; Jiang, Bobi; Yang, Jiamin; Liu, Shenye; Jiang, Shaoen; Li, Yongsheng; Liu, Jie; Huo, Wenyi; Lan, Ke

    2014-01-01

    An ultra-thin layer of uranium nitrides (UN) has been coated on the inner surface of the depleted uranium hohlraum (DUH), which has been proved by our experiment can prevent the oxidization of Uranium (U) effectively. Comparative experiments between the novel depleted uranium hohlraum and pure golden (Au) hohlraum are implemented on Shenguang III prototype laser facility. Under the laser intensity of 6*10^14 W/cm2, we observe that, the hard x-ray (> 1.8 keV) fraction of this uranium hohlraum decreases by 61% and the peak intensity of total x-ray flux (0.1 keV ~ 5 keV) increases by 5%. Two dimensional radiation hydrodynamic code LARED are exploited to interpret the above observations. Our result for the first time indicates the advantage of the UN-coated DUH in generating the uniform x-ray field with a quasi Planckian spectrum and thus has important implications in optimizing the ignition hohlraum design.

  10. Ionizing radiation effect on central venous catheters (CVC) of polyurethane coatings with silver nanoparticles; Efeito da radiacao ionizante nos revestimentos de cateteres venosos centrais (CVC) de poliuretano com nanoparticulas de prata

    Energy Technology Data Exchange (ETDEWEB)

    Heilman, Sonia; Silva, Leonardo G.A., E-mail: sheilman@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Hewer, Thiago L.R.; Souza, Michele L. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto de Quimica

    2015-07-01

    The present work aimed to study the use of ionizing radiation for coating of silver nanoparticles on central polyurethane catheters, providing reduction of infections associated with contamination of catheters introduced into the bloodstream. Silver nanoparticles have physical, chemical and biological properties only when compared to metal on a macroscopic scale, and have been used in the medical field because of its remarkable antimicrobial activity. Titanium dioxide nanoparticles obtained by the sol gel method were used as the coating catheters for subsequent impregnation of silver nanoparticles with ionizing radiation at doses of 25 and 50 kGy. A Raman spectrometry was used to identify the polymorph of titanium oxide, rutile. In trials with (ICP OES) were evaluated amounts of titanium and silver coated catheters in titanium oxide and silver.(author)

  11. ROLE OF THE EGG JELLY COAT IN PROTECTING HYLA REGILLA AND BUFO CANORUS EMBRYOS FROM ULTRAVIOLET B RADIATION DURING DEVELOPMENT

    Science.gov (United States)

    Previous studies have suggested that Ultraviolet B (UVB) radiation may play a role in amphibian population declines. Some of these studies also indicate that egg hatching success is unaltered in some species of anurans as a result of UVB exposure. It has been proposed that the eg...

  12. Radiative and nonradiative recombination of photoexcited excitons in multi-shell-coated CdSe/CdS/ZnS quantum dots

    Science.gov (United States)

    Fu, Y.; Ågren, H.; Kowalewski, J. M.; Brismar, H.; Wu, J.; Yue, Y.; Dai, N.; Thylén, L.

    2009-05-01

    Colloidal quantum dots (QDs) have been widely studied for nanophotonics and bioimaging applications for which the lifetime of their fluorescence is of critical importance. We report experimental and theoretical characterizations of dynamic optical properties of multi-shell-coated CdSe/CdS/ZnS QDs. Quantum-mechanical studies of fundamental optical excitations and Monte Carlo simulations of energy relaxation mechanisms indicate that the excitonic states are densely compacted in the QDs and are easily photoexcited by the laser pulse in the presence of nonradiative electron-phonon interactions. For spherical QDs, the decay time of spontaneous radiative emission of individual photoexcited excitonic states with zero angular momenta is found to be only tens of picoseconds. In our multi-shell QDs, high-energy excitonic states of nonzero angular momenta have to go through a number of nonradiative electron-phonon interaction steps in order to relax to zero-angular-momentum excitonic states for radiative emission, resulting in an effective fluorescence peak at about 2 ns in the photoncount-time relationship. This explains the measured long average fluorescence lifetime of 3.6 ns. Such a long lifetime facilitates the applications of colloidal QDs in areas such as QD-based solar cells, bioimaging and metamaterials.

  13. Dielectric coats effect on the third harmonic generation by a metallic nanoparticle lattice exposed to intense laser radiation

    Science.gov (United States)

    Sepehri Javan, N.; Amjadi, N.; Mohammadzadeh, H.

    2016-12-01

    In this work, we theoretically study the effect of coating of metallic nanoparticles on the third harmonic generation in a periodic three-dimensional lattice. Taking into account the effects of dielectric shell of nanoparticles and microscopic electromagnetic fields on the nonlinear dynamics of electrons, equations describing the laser-nanoparticle interaction are derived in the non-relativistic approximation. We pay special attention on the effects of the thickness and the kind of shell of nanoparticles upon the third harmonic efficiency. It is found that in some frequency areas, existence of shell can amplify the microscopic fields in the place of conduction electrons, which can lead to the improvement of harmonic generation. This amplification could be essential if the frequency region related to the shell effect improvement coincides with that of the plasmon resonance.

  14. 紫外光固化亚光涂料的研究%Development of UV-Curable Matt Coatings

    Institute of Scientific and Technical Information of China (English)

    张申; 文应军

    2001-01-01

    快速固化的紫外光固化亚光涂料的关键是选择适宜的固化速度与氧阻聚时间.通过对活性树脂、活性单体、光引发剂、光引发协同剂等的选择,确定了最佳涂料配方,制备了可快速固化、光泽稳定的亚光漆.

  15. Obtaining self-samples to diagnose curable sexually transmitted infections: a systematic review of patients' experiences.

    Directory of Open Access Journals (Sweden)

    Priyamvada Paudyal

    Full Text Available Routine screening is key to sexually transmitted infection (STI prevention and control. Previous studies suggest that clinic-based screening programmes capture only a small proportion of people with STIs. Self-sampling using non- or minimally invasive techniques may be beneficial for those reluctant to actively engage with conventional sampling methods. We systematically reviewed studies of patients' experiences of obtaining self-samples to diagnose curable STIs.We conducted an electronic search of MEDLINE, EMBASE, CINAHL, PsychINFO, BNI, and Cochrane Database of Systematic Reviews to identify relevant articles published in English between January 1980 and March 2014. Studies were included if participants self-sampled for the diagnosis of a curable STI and had specifically sought participants' opinions of their experience, acceptability, preferences, or willingness to self-sample.The initial search yielded 558 references. Of these, 45 studies met the inclusion criteria. Thirty-six studies assessed patients' acceptability and experiences of self-sampling. Pooled results from these studies shows that self-sampling is a highly acceptable method with 85% of patients reporting the method to be well received and acceptable. Twenty-eight studies reported on ease of self-sampling; the majority of patients (88% in these studies found self-sampling an "easy" procedure. Self-sampling was favoured compared to clinician sampling, and home sampling was preferred to clinic-based sampling. Females and older participants were more accepting of self-sampling. Only a small minority of participants (13% reported pain during self-sampling. Participants were willing to undergo self-sampling and recommend others. Privacy and safety were the most common concerns.Self-sampling for diagnostic testing is well accepted with the majority having a positive experience and willingness to use again. Standardization of self-sampling procedures and rigorous validation of outcome

  16. Evaluation of the cytotoxic effects of PLGA coated iron oxide nanoparticles as a carrier of 5- fluorouracil and mega-voltage X-ray radiation in DU145 prostate cancer cell line.

    Science.gov (United States)

    Hajikarimi, Zahra; Khoei, Samideh; Khoee, Sepideh; Mahdavi, Seied Rabi

    2014-12-01

    The purpose of this study was to investigate the uptake and cytotoxic effects of magnetic poly lactic-co-glycolic acid (PLGA)-coated iron oxide nanoparticles as a carrier of 5-fluorouracil (5-FU) and X-ray on the level of proliferation capacity of DU145 prostate carcinoma cell line in monolayer culture. Following monolayer culture, DU 145 cells were treated with different concentrations of 5-FU or 5-FU loaded nanoparticles for 24 h and 2Gy X-ray (6 Mega-voltage (MV)). The rate of nanoparticles penetration was then measured using atomic adsorption spectroscopy (AAS). The cytotoxicity effect of these nanoparticles with/ without X-ray radiation was evaluated using colony formation assay. Spectroscopy results showed that iron content and therefore the cellular uptake of 5-FU loaded nanoparticles increased with increasing nanoparticle concentrations. Further, the proliferation capacity of the cells decreased with the increase of 5-FU and 5- FU loaded nanoparticle concentrations in combination with X-ray radiation. However the extent of reduction in colony number following treatment with 5-FU-loaded nanoparticles in combination with 2Gy of megavoltage X-ray radiation was significantly more than for free 5-FU. Thus, drug-loaded nanoparticles could deliver 5-FU more efficiently into the cells. PLGA coated iron oxide nanoparticles are therefore effective drug delivery vehicles for 5-FU. PLGA coated iron oxide nanoparticles are biocompatible and this coating is an appropriate surface that can penetrate into the cells.

  17. UV固化涂料研究进展%The Research Development of UV Curing Coating

    Institute of Scientific and Technical Information of China (English)

    杨娟; 成佳辉; 任冬燕

    2011-01-01

    The UV curable coating composition and curing mechanism were summarized.The studies on oligomers such as the domestic and foreign unsaturated polyester,epoxy-acrylate,polyurethane-acrylate,aqueous UV curable polyurethane-acrylate research progress were discussed in detail.According to the thorough research and the continuous development of new products,UV curing coatings would rapidly expand.In the future,there would be more UV curable waterborne coatings and UV curing powder coatings.%综述了UV固化涂料组成与固化机理。详细介绍了国内外不饱和聚酯、环氧丙烯酸酯、聚氨酯丙烯酸酯、水性UV固化聚氨酯丙烯酸酯的研究进展。结合对其深入研究及新产品的不断开发,UV固化涂料将向传统涂料的各个应用领域迅速扩展。预计未来将会出现更多的UV固化水性涂料和UV固化粉末涂料。

  18. Patterning photo-curable light-emitting organic composites by vertical and horizontal capillarity: a general route to photonic nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Mele, Elisa; Camposeo, Andrea; Marco, Carmela De; Persano, Luana; Cingolani, Roberto; Pisignano, Dario [NNL, National Nanotechnology Laboratory of CNR-INFM, Universita del Salento, via Arnesano, I-73100 Lecce (Italy)], E-mail: dario.pisignano@unile.it

    2008-08-20

    We demonstrate the patterning of organic light-emitting composites made by conjugated polymers and photo-curable matrices. Using blends that exhibit both the structural properties of a low-viscosity photo-curable polymer, and the emission features of conjugated light-emitting materials, we study the operational principle of the pattern transfer and the modifications induced by the imprinting and microfluidic procedures on the optical properties of the compounds investigated. The combination of high-resolution silicone and perfluoropolyether elastomeric templates and low-viscosity, light-emitting polymeric blends offers the possibility to easily produce active organic structures with 100 nm scale resolution, thus extending current nanopatterning routes to this important class of composite material.

  19. Evaluation of an intramedullary bone stabilization system using a light-curable monomer in sheep.

    Science.gov (United States)

    Zani, Brett G; Baird, Rose; Stanley, James R L; Markham, Peter M; Wilke, Markus; Zeiter, Stephan; Beck, Aswin; Nehrbass, Dirk; Kopia, Gregory A; Edelman, Elazer R; Rabiner, Robert

    2016-02-01

    Percutaneous intramedullary fixation may provide an ideal method for stabilization of bone fractures, while avoiding the need for large tissue dissections. Tibiae in 18 sheep were treated with an intramedullary photodynamic bone stabilization system (PBSS) that comprised a polyethylene terephthalate (Dacron) balloon filled with a monomer, cured with visible light in situ, and then harvested at 30, 90, or 180 days. In additional 40 sheep, a midshaft tibial osteotomy was performed and stabilized with external fixators or external fixators combined with the PBSS and evaluated at 8, 12, and 26 weeks. Healing and biocompatibility were evaluated by radiographic analysis, micro-computed tomography, and histopathology. In nonfractured sheep tibiae, PBSS implants conformably filled the medullary canal, while active cortical bone remodeling and apposition of new periosteal and/or endosteal bone was observed with no significant macroscopic or microscopic observations. Fractured sheep tibiae exhibited increased bone formation inside the osteotomy gap, with no significant difference when fixation was augmented by PBSS implants. Periosteal callus size gradually decreased over time and was similar in both treatment groups. No inhibition of endosteal bone remodeling or vascularization was observed with PBSS implants. Intramedullary application of a light-curable PBSS is a biocompatible, feasible method for fracture fixation.

  20. UV-curable low surface energy fluorinated polycarbonate-based polyurethane dispersion.

    Science.gov (United States)

    Hwang, Hyeon-Deuk; Kim, Hyun-Joong

    2011-10-15

    UV-curable low surface energy fluorinated polycarbonate-based polyurethane dispersions were synthesized by incorporating a hydroxy-terminated perfluoropolyether (PFPE) into the soft segment of polyurethane. The effects of the PFPE content on the UV-curing behavior, physical, surface, thermal properties and refractive index were investigated. The UV-curing behavior was analyzed by photo-differential scanning calorimetry. The surface free energy of the UV-cured film, which is related to the water or oil repellency, was calculated from contact angle measurements using the Lewis acid-base three liquids method. The surface free energy decreased significantly with increasing fluorine concentration because PFPE in the soft segment was tailored to the surface and produced a UV-cured film with a hydrophobic fluorine enriched surface, as confirmed by X-ray photoelectron spectroscopy. With increasing the fluorine content, the refractive indices of UV-cured films decreased. However, the UV-curing rate and final conversion was decreased with increasing contents of PFPE, which resulted in the decrease of the glass transition temperature (T(g)), crosslink density, tensile strength and surface hardness.

  1. Poly-γ-Glutamic Acid Nanoparticles Based Visible Light-Curable Hydrogel for Biomedical Application

    Directory of Open Access Journals (Sweden)

    József Bakó

    2016-01-01

    Full Text Available Nanoparticles and hydrogels have gained notable attention as promising potential for fabrication of scaffolds and delivering materials. Visible light-curable systems can allow for the possibility of in situ fabrication and have the advantage of optimal applicability. In this study nanogel was created from methacrylated poly-gamma-glutamic acid nanoparticles by visible (dental blue light photopolymerization. The average size of the particles was 80 nm by DLS, and the NMR spectra showed that the methacrylation rate was 10%. Polymerization time was 3 minutes, and a stable nanogel with a swelling rate of 110% was formed. The mechanical parameters of the prepared structure (compression stress 0.73 MPa, and Young’s modulus 0.93 MPa can be as strong as necessary in a real situation, for example, in the mouth. A retaining effect of the nanogel was found for ampicillin, and the biocompatibility of this system was tested by Alamar Blue proliferation assay, while the cell morphology was examined by fluorescence and laser scanning confocal microscopy. In conclusion, the nanogel can be used for drug delivery, or it can be suitable for a control factor in different systems.

  2. Edge coating apparatus with movable roller applicator for solar cell substrates

    Science.gov (United States)

    Pavani, Luca; Abas, Emmanuel

    2012-12-04

    A non-contact edge coating apparatus includes an applicator for applying a coating material on an edge of a solar cell substrate and a control system configured to drive the applicator. The control system may drive the applicator along an axis to maintain a distance with an edge of the substrate as the substrate is rotated to have the edge coated with a coating material. The applicator may include a recessed portion into which the edge of the substrate is received for edge coating. For example, the applicator may be a roller with a groove. Coating material may be introduced into the groove for application onto the edge of the substrate. A variety of coating materials may be employed with the apparatus including hot melt ink and UV curable plating resist.

  3. Polydimethylsiloxane (PDMS Coating onto Magnetic Nanoparticles Induced by Attractive Electrostatic Interaction

    Directory of Open Access Journals (Sweden)

    Carina Sötebier

    2012-05-01

    Full Text Available In this article, we present an efficient synthesis pathway of polydimethylsiloxane (PDMS coated magnetic nanoparticles from hydrophilic polyacrylate coated ferrofluids (NPPAA. A block copolymer based on polydimethylsiloxane is selected for its propensity to interact with the carboxylate functions on the NPPAA. The interaction is due to negative charges on NPPAA and positive ones on the amphiphilic copolymer. The synthesis is achieved by interfacial interaction, simplifying the purification of the PDMS-coated nanoparticles (NPPDMS from subproducts such as ions and water. NPPDMS are well dispersed in hydrophobic solvents (toluene, diethyl ether and can then be embedded into a curable PDMS polymer.

  4. Electrically-controlled near-field radiative thermal modulator made of graphene-coated silicon carbide plates

    Science.gov (United States)

    Yang, Yue; Wang, Liping

    2017-08-01

    In this work, we propose a hybrid near-field radiative thermal modulator made of two graphene-covered silicon carbide (SiC) plates separated by a nanometer vacuum gap. The near-field photon tunneling between the emitter and receiver is modulated by changing graphene chemical potentials with symmetrically or asymmetrically applied voltage biases. The radiative heat flux calculated from fluctuational electrodynamics significantly varies with graphene chemical potentials due to tunable near-field coupling strength between graphene plasmons across the vacuum gap. Thermal modulation and switching, which are the key functionalities required for a thermal modulator, are theoretically realized and analyzed. Newly introduced quantities of the modulation factor, the sensitivity factor and switching factor are studied quite extensively in a large parameter range for both graphene chemical potential and vacuum gap distance. This opto-electronic device with faster operating mode, which is in principle only limited by electronics and not by the thermal inertia, will facilitate the practical application of active thermal management, thermal circuits, and thermal computing with photon-based near-field thermal transport.

  5. Achieving Stable Radiation Pressure Acceleration of Heavy Ions via Successive Electron Replenishment from Ionization of a High-Z Material Coating

    Science.gov (United States)

    Shen, X. F.; Qiao, B.; Chang, H. X.; Kar, S.; Zhou, C. T.; Borghesi, M.; He, X. T.

    2016-10-01

    Generation of monoenergetic heavy ion beams aroused more scientific interest in recent years. Radiation pressure acceleration (RPA) is an ideal mechanism for obtaining high-quality heavy ion beams, in principle. However, to achieve the same energy per nucleon (velocity) as protons, heavy ions undergo much more serious Rayleigh-Taylor-like (RT) instability and afterwards much worse Coulomb explosion due to loss of co-moving electrons. This leads to premature acceleration termination of heavy ions and very low energy attained in experiment. The utilization of a high-Z coating in front of the target may suppress the RT instability and Coulomb explosion by continuously replenishing the accelerating heavy ion foil with co-moving electrons due to its successive ionization under laser fields with Gaussian temporal and spatial profiles. Thus stable RPA can be realized. Two-dimensional and three-dimensional particles-in-cell simulations with dynamic ionization show that a monoenergetic Al13+ beam with peak energy 4.0GeV and particle number 1010 (charge > 20nC) can be obtained at intensity 1022 W/cm2. Supported by the NSF, Nos. 11575298 and 1000-Talents Program of China.

  6. Light wave interference during laser drilling of polymer coatings

    Science.gov (United States)

    Pargellis, A. N.; Au, D. T. W.; Kestenbaum, A.

    1988-12-01

    A CO2 laser has been used to drill holes in a 150-μm-thick, UV-curable, modified acrylate, polymer coating a copper substrate. A typical hole is 100-150 μm in diameter. The holes in this study were each made with a single laser pulse of 10.6-μm wavelength, duration 100 or 200 μs, and 4-20 mJ energy. Two superimposed sets of periodic ripples have been observed on the hole walls. The shorter wavelength varies from 4.0 μm at the top of the hole to 5.3 μm at the bottom of the hole. The longer wavelength appears to be 13.2 μm and is attenuated as the wave propagates towards the copper substrate. The experimental data are compared with values calculated using a model that considers the interference of a standing wave inside the hole with radiation propagating through the dielectric surrounding the hole. The amplitude (trough-to-peak distance) of the waves in the hole wall is about half the wavelength of the standing waves. The long-wavelength waves (13.2 μm) yield ripples in the wall of 6.5-μm amplitude. These ripples give 13.0 μm (0.5 mils) as an ultimate lower limit for laser drilling holes using the 10.6-μm wavelengths obtained with a CO2 laser. Chemical etching of the polymer causes all of the holes to have thin rims surrounding the top of the hole. This is due to accelerated etching of the less cured polymer material inside the hole. A chemical etching process etches away some of the ripple pattern, particularly near the top of the hole.

  7. Evaluation of Thermal Control Coatings and Polymeric Materials Exposed to Ground Simulated Atomic Oxygen and Vacuum Ultraviolet Radiation

    Science.gov (United States)

    Kamenetzky, R. R.; Vaughn, J. A.; Finckenor, M. M.; Linton, R. C.

    1995-01-01

    Numerous thermal control and polymeric samples with potential International Space Station applications were evaluated for atomic oxygen and vacuum ultraviolet radiation effects in the Princeton Plasma Physics Laboratory 5 eV Neutral Atomic Oxygen Facility and in the MSFC Atomic Oxygen Drift Tube System. Included in this study were samples of various anodized aluminum samples, ceramic paints, polymeric materials, and beta cloth, a Teflon-impregnated fiberglass cloth. Aluminum anodizations tested were black duranodic, chromic acid anodize, and sulfuric acid anodize. Paint samples consisted of an inorganic glassy black paint and Z-93 white paint made with the original PS7 binder and the new K2130 binder. Polymeric samples evaluated included bulk Halar, bulk PEEK, and silverized FEP Teflon. Aluminized and nonaluminized Chemfab 250 beta cloth were also exposed. Samples were evaluated for changes in mass, thickness, solar absorptance, and infrared emittance. In addition to material effects, an investigation was made comparing diffuse reflectance/solar absorptance measurements made using a Beckman DK2 spectroreflectometer and like measurements made using an AZ Technology-developed laboratory portable spectroreflectometer.

  8. Design of Bogie Anti-corrosive Thick Coating Intense Radiation Curing Technology and Equipment%浅析转向架防腐厚涂层强辐射固化工艺及设备设计

    Institute of Scientific and Technical Information of China (English)

    于喜年; 赵月红; 刘军

    2011-01-01

    In order to solve the problem on bogie anti-corrosive thick coating curing,then the thickness of anti-corrosion coating 250 μm or/about and the thickness of general dry film and 5~8 kg limited of scraping putty weight were required in accordance with relevant standards and specifications,as requlated with anti-corrosive thickness.Therefore,the still high quality on welding bogie was proposed and reguested.Analysis of bogie anti-corrosion thick coating paint,curing technology and optimal combination of special anti-corrosive coatings on the surface of high speed bogie was made,which is favourable for tech-equipment and process arrangement and coat infense radiation curing.Short-wave radiation heater is the key component of the coating to be cured.A special combination of structural design by elliptical surface and parabolic surface was adopted.It is more conducive to deep directional radiation which makes the solvent in the bottom of anti-corrosive coating evaporate quickly as a result of strong coating adhesion.Therefore short-wave radiation heater is more suitable for curing the thick coating of wheel axis.Intense radiation curing equipment,parametric design and its virtual assembly provide quick and easy reference in design of anti-corrosive coating curing equipment to produce other relevant products for different manufactures being concerned.%为解决转向架防腐厚涂层固化问题,依照相关标准和规范,对防腐涂层厚度作出规定,要求总干膜厚度为250μm左右,并对腻子的刮涂重量限制在5~8 kg以内,对转向架的焊接质量提出了更高的要求;分析了转向架防腐厚涂层涂覆、固化工艺以及高速动车转向架专用防腐涂料的最优组合,有利于涂层强辐射固化工艺设计和工艺过程安排;短波辐射加热器为涂层固化的关键部件,采用抛物面与椭圆面组合的特殊结构设计,更有利于深层定向辐射,使防腐涂层的底部溶剂迅速挥发,增强了涂层的附

  9. Preparation and Properties of Infrared Radiation Energy-saving Coating with High Thermal Shock Resistance%高抗热震性红外辐射节能涂层的制备与性能研究

    Institute of Scientific and Technical Information of China (English)

    陆磊; 樊希安; 胡晓明; 张坚义; 吴朝阳; 杨帆; 蔡新志

    2014-01-01

    以堇青石、SiC、Cr2O3、TiO2、SiO2为原料,与磷酸盐胶粘结剂配料混匀后,经机械搅拌制备红外辐射涂料,采用刷涂的方式在高铝砖基体表面制备红外辐射节能涂层。采用TG-DSC研究分析红外辐射粉末的热稳定性,利用涂-4杯和漆膜附着力测定仪对涂料的流动性能和涂层与基体的结合强度进行表征,采用空冷和水淬方式研究涂层的抗热震性能,并探讨了碳化硅的含量对涂层红外发射率的影响。研究结果表明:胶粉比为2:1时,获得的涂料均匀,流动性最好;以磷酸盐胶粘结剂制备的红外辐射涂料经1100℃以上高温瓷化后,红外辐射涂层与基体的结合力增强,涂层抗热震性能良好;碳化硅含量为40%时,制备的复合红外辐射涂层具有最优的红外辐射性能。此外,在炭砖焙烧窑上使用该红外辐射涂料后,炉内温度提高了128℃,降低能耗8%左右。%Infrared radiation paint was prepared from cordierite, SiC, Cr2O3, TiO2, SiO2 as the initial raw material by mechanical mixing with phosphate adhesive. And then an energy-saving infrared radiation coating was prepared on high aluminum brick surface by brushing process. Thermal stability of the infrared radiation powders were investigated by Thermo Gravimetric-Differential Scanning Calorimeter (TG-DSC). The flowability of the prepared paint and the adhesion between infrared radiation coating and substrate were characterized by paint-4 cup and paint film adhesion tester. The thermal shock resistance of the obtained coating was investigated by water cooling and air cooling. The effect of SiC content on the emissivity of the coating was discussed. The research results show that:the paint is well-distributed and the flowability is quite good at the ratio 2:1 of adhesive to infrared radiation powders. The adhesion strength between coating and substrate increased after high temperature heat treatment at 1100℃. The

  10. Hybrid glass coatings for optical fibers: effect of coating thickness on strength and dynamic fatigue characteristics of silica fibers

    Science.gov (United States)

    Wojcik, A. B.; Matthewson, M. J.; Castelino, K. T.; Wojcik, J.; Walewski, A.

    2006-04-01

    Specialty optical fibers operating in harsh aerospace environments are typically exposed to high temperatures and elevated humidity. This calls for better performing protective coatings. Recently developed sol-gel derived inorganicorganic hybrid materials called hybrid glass offered improved protective performance as compared to standard dual polymer coated fibers [1]. In this paper we examine the effectiveness of online UV curing for the protective ability of hybrid glass coatings. For this purpose two types of UV-curable hybrid glass candidates representing two different concentrations of acrylate groups were applied online to silica fibers as single and dual coats. Samples of fibers were collected and subjected to dynamic fatigue testing by two-point bending. The stress corrosion parameter, n, as well as the strength of the fibers were determined. Both the strength and n were higher for fibers with two layers of coating as compared to single coatings even when the thickness of both one and two layer coatings was the same. This may be caused by the greater degree of cross linking of the inorganic component when the coating is exposed twice to the heat generated in the UV chamber. Coating materials with reduced acrylate group content had higher values of the fatigue parameter n but at the same time reduced strength.

  11. Optical coatings: Laser radiation damage. (Latest citations from the INSPEC: Information Services for the Physics and Engineering Communities database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    1993-02-01

    The bibliography contains citations concerning theoretical aspects and experimental investigations of laser induced damage to optical coatings. The citations examine damage thresholds of metal, dielectric, and metal-dielectric coating materials used in high power lasers. Topics also include the effects of laser damage on coating processes and materials, and substrate materials which influence the origin and morphology of laser damage. Laser sources are also considered. (Contains a minimum of 100 citations and includes a subject term index and title list.)

  12. Research advance of resin coated proppants%树脂覆膜支撑剂研究进展

    Institute of Scientific and Technical Information of China (English)

    张伟民; 刘三琴; 崔彦立; 钱继贺; 郭伟峰; 王建英

    2011-01-01

    The domestic and foreign research advance in preparation,modification and application of pre-cured resin coated proppant and curable resin coated proppant were reviewed.The current problems and the future development direction of resin coated proppant were presented.%综述了国内外预固化和可固化树脂覆膜支撑剂的制备、改性研究及应用进展,并指出了目前树脂覆膜支撑剂存在的问题和今后的发展方向。

  13. Study on Preparing Adhesive of High Radiation Coatings Used in Power Station Boiler%电站锅炉中高辐射涂层用胶粘剂的研制

    Institute of Scientific and Technical Information of China (English)

    桂老虎; 陈九磅; 王平; 程银健

    2012-01-01

    在发电厂,高辐射涂层广泛应用于锅炉的管道,但适合于该涂层使用的优质胶粘剂一直是一个瓶颈.研制出具有低腐蚀、高粘度、耐高温特点的胶粘剂,对提高高辐射涂层的综合性能至关重要.众所周知,无机磷酸盐胶粘剂拥有有机胶和硅溶胶不可比拟的耐高温、低固化收缩率等优点,本文简述了磷酸盐胶粘剂的制备原料及工艺,试验中以磷酸二氢铝为主要成分,同时加入pH调节剂、缓蚀剂、催干剂、增稠剂等,制备出了一种可以在24 h内表面干燥、对金属表面有较小的腐蚀、耐温800℃、高粘性的胶粘剂.%In power plants, high radiation coating is widely used in boiler tubes, however, it's a big bottleneck for the high radiation to use in the coating. Development of adhesive, with low corrosion, high viscosity and high temperature resistant characteristics to improve the comprehensive performance of high radiation coating is very important. As everyone knows, inorganic phosphate coating is superior to organic gel and silica sol in high- temperature and low curing shrinkage. The high viscosity coatings with phosphate bonded di-hydrogen aluminum as the main ingredient are prepared. By adding agents for adjusting pH, corrosion inhibitors, driers, thickeners, we have coatings whose surface can dry within 24 h, get a low corrosion on the metal by resisting to the temperature of 800 癈.

  14. The Biomineralization of a Bioactive Glass-Incorporated Light-Curable Pulp Capping Material Using Human Dental Pulp Stem Cells

    Science.gov (United States)

    Jun, Soo-Kyung; Lee, Hae-Hyoung

    2017-01-01

    The aim of this study was to investigate the biomineralization of a newly introduced bioactive glass-incorporated light-curable pulp capping material using human dental pulp stem cells (hDPSCs). The product (Bioactive® [BA]) was compared with a conventional calcium hydroxide-incorporated (Dycal [DC]) and a light-curable (Theracal® [TC]) counterpart. Eluates from set specimens were used for investigating the cytotoxicity and biomineralization ability, determined by alkaline phosphatase (ALP) activity and alizarin red staining (ARS). Cations and hydroxide ions in the extracts were measured. An hDPSC viability of less than 70% was observed with 50% diluted extract in all groups and with 25% diluted extract in the DC. Culturing with 12.5% diluted BA extract statistically lowered ALP activity and biomineralization compared to DC (p 0.05). Ca (~110 ppm) and hydroxide ions (pH 11) were only detected in DC and TC. Ionic supplement-added BA, which contained similar ion concentrations as TC, showed similar ARS mineralization compared to TC. In conclusion, the BA was similar to, yet more cytotoxic to hDPSCs than, its DC and TC. The BA was considered to stimulate biomineralization similar to DC and TC only when it released a similar amount of Ca and hydroxide ions. PMID:28232937

  15. The Biomineralization of a Bioactive Glass-Incorporated Light-Curable Pulp Capping Material Using Human Dental Pulp Stem Cells

    Directory of Open Access Journals (Sweden)

    Soo-Kyung Jun

    2017-01-01

    Full Text Available The aim of this study was to investigate the biomineralization of a newly introduced bioactive glass-incorporated light-curable pulp capping material using human dental pulp stem cells (hDPSCs. The product (Bioactive® [BA] was compared with a conventional calcium hydroxide-incorporated (Dycal [DC] and a light-curable (Theracal® [TC] counterpart. Eluates from set specimens were used for investigating the cytotoxicity and biomineralization ability, determined by alkaline phosphatase (ALP activity and alizarin red staining (ARS. Cations and hydroxide ions in the extracts were measured. An hDPSC viability of less than 70% was observed with 50% diluted extract in all groups and with 25% diluted extract in the DC. Culturing with 12.5% diluted BA extract statistically lowered ALP activity and biomineralization compared to DC (p0.05. Ca (~110 ppm and hydroxide ions (pH 11 were only detected in DC and TC. Ionic supplement-added BA, which contained similar ion concentrations as TC, showed similar ARS mineralization compared to TC. In conclusion, the BA was similar to, yet more cytotoxic to hDPSCs than, its DC and TC. The BA was considered to stimulate biomineralization similar to DC and TC only when it released a similar amount of Ca and hydroxide ions.

  16. The treatment of madness in the nineteenth and twentieth centuries: discourses about curability in Spanish mental health care, 1890-1917.

    Science.gov (United States)

    Domingo, José Javier Plumed; Moreno, Luis Miguel Rojo

    2016-01-01

    This article studies the discourses about curability constructed by Spanish mental health practitioners in the transition from the nineteenth to the twentieth century. While in the 1870s and 1880s the predominant discourse promoted by doctors attached to private institutions was extremely optimistic, it subsequently changed and became more pessimistic regarding treatment outcomes. However, given phrenopathists' professional needs, they continued to profess more or less unshakeable confidence in the therapeutic abilities of psychiatry. The reception of new nosologies, such as Kraepelin's, depended in part on contemporary mental health practitioners' stance on curability and was accompanied by ambivalence.

  17. Research progress of photo-curable adhesives for iatrology%光固化医用胶粘剂研究进展

    Institute of Scientific and Technical Information of China (English)

    师瑞峰; 朱光明

    2011-01-01

    The some current application fields of photo-curable adhesives for iatrology,including adhesives for soft tissue,adhesives for odontology,adhesives for orthopaedics and adhesives for iatrical instrument,were introduced. The future development of photo-curable adhesives for iatrology was expected.%介绍了目前光固化医用胶粘剂的几个应用领域,包括软组织用胶粘剂、齿科用胶粘剂、骨科用胶粘剂以及医疗器械用胶粘剂等,并对其未来发展进行了展望.

  18. Evaluation of Viscosity Characteristics of Spin-Coated UV Nanoimprint Resin

    Science.gov (United States)

    Hidemasa Atobe,; Hiroshi Hiroshima,; Qing Wang,

    2010-06-01

    The viscosity of a UV-curable resin used in UV nanoimprint is one of the key parameters to determine the process speed of resin filling in the recesses of a mold. We have developed an apparatus to measure the viscosity of a spin-coated thin liquid film on a wafer. With this viscosity measuring apparatus we examined the effect of the film thickness, exposure of resin to atmosphere, and temperature of resin on the viscosity of PAK-01, which is a UV-curable resin commonly employed in UV nanoimprint. The viscosity of this resin with its film thickness larger than 2.3 μm showed a constant value of 83 mPa\\cdots, which is almost the same as that of the bulk PAK-01. At below 2.3 μm, the viscosity seemed to increase with decreasing film thickness. The viscosity of the spin-coated resin was also found to increase with the duration of its exposure to atmosphere; for a 30 min exposure to atmosphere, the viscosity reached up to 461 mPa\\cdots. It is considered that during the prolonged exposure, the volatile component of the resin evaporated. When subjected to heat treatment, the viscosity of the UV-curable resin did not seem to depend on film thickness and maintained a steady value of 385 mPa\\cdots. It was found that as the film thickness decreased the viscosity approached the value obtained by heat treatment.

  19. Solid pseudopapillary epithelial neoplasm--a rare but curable pancreatic tumour in young women.

    Science.gov (United States)

    Frost, M; Krige, J E J; Bornman, P C; Panieri, E; Beningfield, S J; Wainwright, H

    2011-04-01

    Solid pseudopapillary epithelial neoplasms (SPENs) of the pancreas are rare but curable tumours that have a low-grade malignant potential and occur almost exclusively in young women, with an excellent prognosis after complete resection. This study examines the clinicopathological characteristics of these tumours and evaluates the role of surgery in relation to their size and location. We reviewed the pre-, intra- and postoperative data on 21 patients with SPENs who underwent resection during a 30-year period. Data including demographic information, presenting symptoms and signs, extent of operation, histology, tumour markers and postoperative complications were evaluated to establish the optimal surgical management. All 21 tumours occurred in women (mean age 24.6 years, range 13-51 years). Sixteen patients presented with nonspecific abdominal complaints and a palpable abdominal mass, in 1 patient the tumour was found during emergency laparotomy for a complicated ovarian cyst, 1 patient presented with severe abdominal pain and shock due to a ruptured tumour, and in 3 patients the tumour was detected incidentally during imaging. The correct pre-operative diagnosis of SPEN was made in 10 patients. Incorrect preoperative diagnoses included hydatid cyst (3 patients), mesenteric cyst (2), pancreatic cystadenoma (2), ovarian cysts (1), islet cell tumour of the pancreas (1), and cavernous haemangioma of the liver (1). The mean diameter of the tumours was 12.5 cm (range 8 - 20 cm), and they occurred in the head (8), neck (5), body (2), and tail (6) of the pancreas. All SPENs were resected. Five patients had a pylorus-preserving pancreaticoduodenectomy, 4 a central pancreatectomy with distal pancreaticogastrostomy, 8 a distal pancreatectomy, 3 a local resection and one a total pancreatectomy and portal vein graft. In 1 patient, 2 liver metastases were resected in addition to the pancreatic primary tumour. The patient who presented in shock with tumour rupture and bleeding

  20. Ionizing radiation post-curing of objects produced by stereolithography and other methods

    Science.gov (United States)

    Howell, David H.; Eberle, Claude C.; Janke, Christopher J.

    2000-01-01

    An object comprised of a curable material and formed by stereolithography or another three-dimensional prototyping method, in which the object has undergone initial curing, is subjected to post-curing by ionizing radiation, such as an electron beam having a predetermined beam output energy, which is applied in a predetermined dosage and at a predetermined dose rate. The post-cured object exhibits a property profile which is superior to that which existed prior to the ionizing radiation post-curing.

  1. Synthesis of a Novel UV Curable Aqueous Dispersion Polyurethane PDHA-PEDA-PU and the Properties of Cured Film

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A novel ultraviolet (UV) curable aqueous dispersion polyurethane PDHA-PEDA-PU was synthesized based on isophorone diisocyanate (IPDI), polyester dihydric alcohol (PDHA),dimethylol propionic acid (DMPA), pentaerythritol diacrylate (PEDA), 2-hydroxyethyl acrylate (HEA) and triethylamine (TEA). Acrylate groups were incorporated in the side and end of PDHA-PEDA-PU chain. The C=C content in the chain can be controlled easily through the change of IPDI/PDHA/PEDA ratio. Fourier transform infrared spectroscopy (FTIR) was used to identify the structure of prepolymer, aqueous dispersion and cured polyurethane. The curing rule of the polyurethane for different C=C content has been investigated depending on the change of C=C content during the curing process. The hardness, thermal stability and scrub resistance to MEK of UV cured PDHA-PEDA-PU were also discussed for the samples with different C=C content.

  2. Wetting characteristics of the anodic aluminum oxide template and fabrication of cracks using ultraviolet curable resin solution

    Science.gov (United States)

    Sung Yoon, Jae; Phuong, NguyenThi; Hwan Kim, Jeong; Choi, Doo-Sun; Whang, Kyung-hyun; Yoo, Yeong-eun

    2014-03-01

    We have investigated the wetting characteristics of the anodic aluminum oxide (AAO) template with ultraviolet curable polymer resin. The wettability of the template depends on the pore size on the surface, where it is improved with smaller pores and vice versa. Plasma treatment on the surface of the template is used to improve the wettability and the adhesion of the cured polymer to the template. And we also introduce the cracks on the polymer layer for possible application as nano-sized cavities. The resin within the pore is cleaved during the curing process so that cavities or cracks could be made which are much smaller than the original pores of the AAO template.

  3. Aligned Structures of Fe3O4 Nanoparticles in a Curable Polymer Carrier Induced by a Magnetic Field

    Institute of Scientific and Technical Information of China (English)

    FANG Wen-Xiao; HE Zhen-Hui; XU Xue-Qing; SHEN Hui

    2005-01-01

    @@ To understand the interaction in dipolar systems, it is necessary to investigate the structures formed by the interacting particles. We introduce a polymer acrylic resin carrier to fix the structures in the magnetic fluid(Fe3O4). An aligned structure is investigated, which is formed under a magnetic field, and fixed in the cured acrylic resin film by evaporating the solvent at room temperature. The aligned structure is confirmed with the help of optical microscopy and optical diffraction for the cured film. Furthermore, we find substructures by using a scanning electronic microscope. Based on the curable and observable structures, a platform can be developed for investigating the aligned structures and configurations dominant by dipolar interaction. This is also helpful for the development of magnetic devices with orderly aligned structures.

  4. Effect of light-curable fluoride varnish on enamel demineralization adjacent to orthodontic brackets: an in-vivo study.

    Science.gov (United States)

    Mehta, Anurag; Paramshivam, Ganesh; Chugh, Vinay Kumar; Singh, Surjit; Halkai, Sudha; Kumar, Santosh

    2015-11-01

    The purpose of this in-vivo study was to evaluate the effect of a single application of Clinpro XT (3M ESPE, Pymble, New South Wales, Australia), a light-curable fluoride varnish, on enamel demineralization adjacent to orthodontic brackets. Thirty-eight patients (152 teeth) whose orthodontic treatment involved extraction of 4 first premolars were recruited. Two premolars each were assigned to the control group (no treatment) and the experimental group (received fluoride varnish application). The study was designed as a nonrandomized split-mouth study in which diagonally opposite quadrants received the same treatment. After the bonding procedures, a sectional T-loop was ligated into each bracket to serve as a site for plaque retention for enhanced demineralization. Clinpro XT was applied on the buccal surfaces adjacent to the brackets on all teeth in the experimental group only. Teeth in both groups were extracted after 15 days (n = 30), 30 days (n = 30), 45 days (n = 30), 90 days (n = 18), and 120 days (n = 18). Buccolingual sections were then evaluated under polarized light microscopy. After we excluded the dropouts, the mean depth of the demineralized enamel lesions was measured in final sample of 126 teeth. The Mann-Whitney test was used for comparison of the groups. In the control group, the depths of the demineralized enamel lesions increased from 30 to 120 days, whereas in the experimental group no sign of demineralization was noted throughout the observation period except for 3 teeth. Significant differences in the depths of demineralized lesions were found between the study groups. Clinpro XT light-curable fluoride varnish may be a reasonable alternative in the reduction of enamel demineralization around orthodontic brackets, especially in noncompliant and high-risk patients. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  5. Chronic TiO₂ nanoparticle exposure to a benthic organism, Hyalella azteca: impact of solar UV radiation and material surface coatings on toxicity.

    Science.gov (United States)

    Wallis, Lindsay K; Diamond, Stephen A; Ma, Hongbo; Hoff, Dale J; Al-Abed, Souhail R; Li, Shibin

    2014-11-15

    There is limited information on the chronic effects of nanomaterials to benthic organisms, as well as environmental mitigating factors that might influence this toxicity. The present study aimed to fill these data gaps by examining various growth endpoints (weight gain, instantaneous growth rate, and total protein content) for up to a 21 d sediment exposure of TiO2 nanoparticles (nano-TiO2) to a representative benthic species, Hyalella azteca. An uncoated standard, P25, and an Al(OH)3 coated nano-TiO2 used in commercial products were added to sediment at 20 mg/L or 100 mg/L Under test conditions, UV exposure alone was shown to be a greater cause of toxicity than even these high levels of nano-TiO2 exposure, indicating that different hazards need to be addressed in toxicity testing scenarios. In addition, this study showed the effectiveness of a surface coating on the decreased photoactivity of the material, as the addition of an Al(OH)3 coating showed a dramatic decrease in reactive oxygen species (ROS) production. However, this reduced photoactivity was found to be partially restored when the coating had been degraded, leading to the need for future toxicity tests which examine the implications of weathering events on particle surface coatings.

  6. Preparation of hydrophobic coatings

    Science.gov (United States)

    Branson, Eric D.; Shah, Pratik B.; Singh, Seema; Brinker, C. Jeffrey

    2009-02-03

    A method for preparing a hydrophobic coating by preparing a precursor sol comprising a metal alkoxide, a solvent, a basic catalyst, a fluoroalkyl compound and water, depositing the precursor sol as a film onto a surface, such as a substrate or a pipe, heating, the film and exposing the film to a hydrophobic silane compound to form a hydrophobic coating with a contact angle greater than approximately 150.degree.. The contact angle of the film can be controlled by exposure to ultraviolet radiation to reduce the contact angle and subsequent exposure to a hydrophobic silane compound to increase the contact angle.

  7. Coatings and Tints of Spectacle Lenses

    Directory of Open Access Journals (Sweden)

    H. Zeki Büyükyıldız

    2012-10-01

    Full Text Available Spectacle lenses are made of mineral or organic (plastic materials. Various coatings and tints are applied to the spectacle lenses according to the characteristic of the lens material, and for the personal needs and cosmetic purpose. The coatings may be classified in seven groups: 1 Anti-reflection coatings, 2 Hard coatings, 3 Clean coat, 4 Mirror coatings, 5 Color tint coating (one of coloring processes, 6 Photochromic coating (one of photochromic processes, and 7 Anti-fog coatings. Anti-reflection coatings reduce unwanted reflections from the lens surfaces and increase light transmission. Hard coatings are applied for preventing the plastic lens surface from scratches and abrasion. Hard coatings are not required for the mineral lenses due to their hardness. Clean coat makes the lens surface smooth and hydrophobic. Thus, it prevents the adherence of dust, tarnish, and dirt particles on the lens surface. Mirror coatings are applied onto the sunglasses for cosmetic purpose. Color tinted and photochromic lenses are used for sun protection and absorption of the harmful UV radiations. Anti-fog coatings make the lens surface hydrophilic and prevent the coalescence of tiny water droplets on the lens surface that reduces light transmission. (Turk J Ophthalmol 2012; 42: 359-69

  8. Gravure printing of transparent conducting ITO coatings for display applications

    Science.gov (United States)

    Puetz, Joerg; Heusing, Sabine; de Haro Moro, Marcos; Ahlstedt, C. Mikael; Aegerter, Michel A.

    2005-09-01

    Transparent conducting coatings and patterns of ITO (indium tin oxide) were deposited by a direct gravure printing on PET foils using nanoparticle-based UV-curable inks. Solid areas with thicknesses ranging between 300 and >1000 nm were obtained by varying the ink composition (e.g. ITO content, solvents) and fundamental parameters of the printing plate such as the line density. The best ITO coating patterns showed a sheet resistance of 3 to 10 kΩ□ and a transmission of up to 88 % with a haze of less than 1 %. One of the most crucial steps during film formation is the drying of the wet film as it changes the rheology and polarity of the ink and in consequence decisively influences the film formation. Typical fields of application of the gravure-printed ITO patterned electrodes include smart windows, flexible displays and printed electronics.

  9. Innovative fiber coating systems based on organic modified ceramics

    Science.gov (United States)

    Schuster, Kay; Kobelke, Jens; Rose, Klaus; Helbig, Manfred; Zoheidi, Mohammad; Heinze, Alexander

    2010-02-01

    We describe the application of inorganic organic hybrid materials (ORMOCERs) as optical fiber coatings for use in Fiber Bragg Grating sensors and high power transmission fibers. The materials are UV curable, enable a single layer thickness of about 50 μm and show high a high peak temperature stability >300 °C. Regarding the fiber protection the coatings have been investigated using tensile strength measurements before and after temperature load. Best coatings maintain the high tensile strength of 68 N (125 μm fiber) with a Weibull parameter of 182 after a temperature cycling up to 300 °C. For the first time a low refractive index ORMOCER will be presented showing a numerical aperture of 0.47 at a wavelength of 1000 nm on a pure silica fiber. This corresponds to a refractive index of 1.37. The fiber possesses a fiber loss of 18 dB/km at a wavelength of 1000 nm. The fibers have been coated using a gravity as well as pressure technology. The latter possesses extremely minimized die equipment and is therefore well applicable for small coating amounts. The so called dead volume within the coating die is about 1 ml. The overall dead volume is only influenced by the supply pipe and can be reduced down to 5 ml.

  10. Chronic TiO2 nanoparticle exposure to a benthic organism, Hyalella azteca: Impact of solar UV radiation and material surface coatings on toxicity

    Science.gov (United States)

    The present study examined the chronic toxicity of TiO2 nanoparticles (nano-TiO2) to a representative benthic species, Hyalella azteca, using an industry standard, P25, and a coated nano-TiO2 used in commercial products. There is limited information on the chronic effects of nano...

  11. Chronic TiO2 nanoparticle exposure to a benthic organism, Hyalella azteca: Impact of solar UV radiation and material surface coatings on toxicity

    Science.gov (United States)

    The present study examined the chronic toxicity of TiO2 nanoparticles (nano-TiO2) to a representative benthic species, Hyalella azteca, using an industry standard, P25, and a coated nano-TiO2 used in commercial products. There is limited information on the chronic effects of nano...

  12. Development of novel cycloaliphatic siloxanes for thermal and UV-curable applications

    Science.gov (United States)

    Chakraborty, Ruby

    Siloxanes have been extensively used as additives to modulate surface properties such as surface tension, hydrophobicity/hydrophobicity, and adhesion, etc. Although, polydimethyl -siloxane and polydiphenylsiloxane are the most commonly used siloxanes, the properties are at extremes in terms of glass transition temperature and flexibility. It is proposed that the ability to control the properties in between the these extremes can be provided by cycloaliphatic substitutions at the siloxane backbone. It is expected that this substitution might work due to the intermediate backbone rigidity. In order to achieve the above objectives, a synthetic route was developed to prepare cycloaliphatic (cyclopentane and cyclohexane) silane monomers followed by subsequent polymerization and functionalizations to obtain glycidyl epoxy, aliphatic amine and methacrylate telechelic siloxanes. The siloxanes were either thermally or UV-cured depending on end functionalizations. Chemical characterization of monomers, oligomers and polymers were performed using 1H, 13C, 29Si-NMR, FT-IR and GPC. The curing kinetics of photo-induced reactions were investigated through photo-differential scanning calorimetry (PDSC). The oxygen permeability, mechanical, coatings, and release properties of siloxanes were studied as a function of the backbone substitutions. The mechanical, coatings and released properties of cycloaliphatic siloxanes improved with respect to polydimethylsiloxanes. The thermal analysis of the cured films were carried out using differential scanning calorimetry (DSC). Viscoelastic properties of the cured siloxanes due to the variation of substitution at the siloxane backbone were measured using dynamic mechanical thermal analysis (DMTA). The cycloaliphatic substituted siloxanes showed an increased glass transition temperature and permeability but reduced crosslink density, conversion, and rate of curing with respect to polydimethylsiloxanes. Hybrids of siloxanes were prepared with

  13. 紫外光固化薄层保温隔热涂料的研制%Preparation of ultraviolet-curable thin-layered heat-insulating paint

    Institute of Scientific and Technical Information of China (English)

    谈素芬; 鲁钢

    2013-01-01

    A UV-curable thin-layered heat-insulating paint was prepared with epoxidized soybean oil acrylate as film forming resin and hollow glass beads as filler.The effect of the content of hollow glass bead on mechanical properties,diffuse reflectivity,thermal conductivity,and heat-insulating performance of the coating was studied.The dosage of hollow glass bead was determined as 8%.The thermal reflectivity and heat-insulating performance of the coatings with different thicknesses were compared.The 200-μm thick coating features diffuse reflectivity 75%,heat conductivity 0.069 W/(m·K),heat-insulating temperature difference 27 ℃,adhesion strength 1 grade,pencil hardness 4H,and impact strength higher than 50 kg·cm.The temperature difference between the water in the glass bottle protected with the heat insulation coating and blank sample after placing for 30 min is 26 ℃.%以环氧大豆油丙烯酸酯作为成膜树脂,添加中空玻璃微珠作为隔热填料,制得一种紫外光固化薄层保温隔热涂料.研究了中空玻璃微珠的用量对涂层机械性能、漫反射率、导热率和保温隔热性能的影响,确定了涂料配方中空玻璃微珠的添加量为8%.比较了不同厚度涂层的热反射率和隔热保温性能.当涂层厚度为200 μm时,所制备的隔热保温涂层的漫反射率达75%,导热率为0.069 W/(m·K),放置30 min后的水温与空白试样的水温温差为26℃,隔热温差达27℃,涂膜附着力为l级,铅笔硬度可达4H,冲击强度大于50 kg·cm.

  14. Epidemiology of curable sexually transmitted infections among women at increased risk for HIV in northwestern Tanzania: inadequacy of syndromic management.

    Directory of Open Access Journals (Sweden)

    Suzanna C Francis

    Full Text Available BACKGROUND: Curable, non-viral pathogens account for a significant burden of sexually transmitted infections (STIs, and there is established evidence that STIs increase both HIV acquisition and transmission. We investigated the prevalence, trends, and factors associated with Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis and Treponema pallidum, and the performance of syndromic management, among a cohort of women working in bars, hotels, and other food and recreational facilities near large-scale mines in northwestern Tanzania. METHODS: HIV-negative women aged 18-44 years (N = 966 were enrolled and followed for 12 months in a microbicides feasibility study. We collected sociodemographic and behavioural data, performed clinical examinations, and tested for STIs, at enrolment and 3-monthly. Risk factors for STIs were investigated using logistic regression models with random effects. Sensitivity, specificity and predictive values of syndromic management were calculated. RESULTS: At enrolment, the prevalences of C. trachomatis, N. gonorrhoeae, T. vaginalis, and high-titre active syphilis were 111/956 (12%, 42/955 (4%, 184/945 (19% and 46/965 (5%, respectively. There were significant decreases over time for C. trachomatis and T. vaginalis (OR trend per month: 0.94 [95% CI 0.91, 0.97]; and 0.95 [0.93, 0.98], respectively; both p<0.001. The majority of these infections were not diagnosed by the corresponding syndrome; therefore, most participants were not treated at the diagnosis visit. Syndromic management was poorly predictive of laboratory-diagnosed infections. We identified a number of risk factors for STIs, including low educational level, some sexual behaviours, and ever having been pregnant. CONCLUSIONS: This analysis demonstrates that the prevalences of curable STIs are high among women who work in food and recreational facilities in northwestern Tanzania. Most of these infections are missed by syndromic management

  15. Morbus Coats

    Science.gov (United States)

    Förl, B.; Schmack, I.; Grossniklaus, H.E.; Rohrschneider, K.

    2010-01-01

    Der fortgeschrittene Morbus Coats stellt im Kleinkindalter eine der schwierigsten Differenzialdiagnosen zum Retinoblastom dar. Wir beschreiben die klinischen und histologischen Befunde zweier Jungen im Alter von 9 und 21 Monaten mit einseitiger Leukokorie. Trotz umfassender Diagnostik mittels Narkoseuntersuchung, MRT und Ultraschall konnte ein Retinoblastom nicht sicher ausgeschlossen werden, und es erfolgte eine Enukleation. Histologisch wurde die Diagnose eines Morbus Coats gesichert. Da eine differenzialdiagnostische Abgrenzung zwischen Morbus Coats und Retinoblastom schwierig sein kann, halten wir in zweifelhaften Fällen auch angesichts der eingeschränkten Visusprognose und potenzieller Sekundärkomplikationen beim fortgeschrittenen Morbus Coats eine Enukleation für indiziert. PMID:18299842

  16. Miliary tuberculosis with no pulmonary involvement in myelodysplastic syndromes: a curable, yet rarely diagnosed, disease: case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Krambovitis Elias

    2008-03-01

    Full Text Available Abstract Background Although tuberculosis is not uncommon among patients with myelodysplastic syndrome (MDS, only a few reports of such patients suffering from miliary tuberculosis (MT exist. MT often presents as a fever of unknown origin and it is a curable disease, yet fatal if left untreated. Case presentation We report a case of MT with no clinical or laboratory indications of pulmonary involvement in a patient with MDS, and review the relevant literature. Mycobacterium tuberculosis was isolated from the liquid culture of a bone marrow aspirate. Conclusion Even if the initial diagnostic investigation for a fever of obscure etiology is negative, MT should not be excluded from the differential diagnosis list. Since it is a curable disease, persistent and vigorous diagnostic efforts are warranted. In suspected cases, mycobacterial blood cultures should be collected as soon as possible after hospital admission and early bone marrow aspirate with mycobacterial cultures is advocated.

  17. EFFECTS OF SOME PHENYLETHYNYLSILICON COMPOUNDS ON HEAT-CURABLE SILICONE RUBBER Ⅲ 1,1,3,3-TETRAMETHYL- 1,3-DIPHENYLETHYNYL-DISILOXANE

    Institute of Scientific and Technical Information of China (English)

    FENG Shengyu; YU Shuqi; LI Shijun; ZHANG Shengyou; CHEN Jianhua; DU Zuodong

    1995-01-01

    We have shown that some phenylethynylsilicon compounds are good cure crosslinkers of heat-curable silicone rubber(HCSR). In this paper the effects of 1,1,3,3-tetramethyl1,3-diphenylethynyldisiloxane (TMDPDS) as a crosslinker on HCSR were studied. The vulcanizates with fine mechanical properties could be obtained with suitable amounts of TMDPDS. Sol fractions, and crosslinking density of vulcanizates and vulcanization retardation effect of TMDPDS on hydrosilation curing silicone rubber were also discussed.

  18. Primary pancreatic lymphoma – pancreatic tumours that are potentially curable without resection, a retrospective review of four cases

    Directory of Open Access Journals (Sweden)

    Chin Melvin T

    2006-05-01

    Full Text Available Abstract Background Primary pancreatic lymphomas (PPL are rare tumours of the pancreas. Symptoms, imaging and tumour markers can mimic pancreatic adenocarcinoma, but they are much more amenable to treatment. Treatment for PPL remains controversial, particularly the role of surgical resection. Methods Four cases of primary pancreatic lymphoma were identified at Prince of Wales Hospital, Sydney, Australia. A literature review of cases of PPL reported between 1985 and 2005 was conducted, and outcomes were contrasted. Results All four patients presented with upper abdominal symptoms associated with weight loss. One case was diagnosed without surgery. No patients underwent pancreatectomy. All patients were treated with chemotherapy and radiotherapy, and two of four patients received rituximab. One patient died at 32 months. Three patients are disease free at 15, 25 and 64 months, one after successful retreatment. Literature review identified a further 103 patients in 11 case series. Outcomes in our series and other series of chemotherapy and radiotherapy compared favourably to surgical series. Conclusion Biopsy of all pancreatic masses is essential, to exclude potentially curable conditions such as PPL, and can be performed without laparotomy. Combined multimodality treatment, utilising chemotherapy and radiotherapy, without surgical resection is advocated but a cooperative prospective study would lead to further improvement in treatment outcomes.

  19. Optimization of UV LED-Curable Ink for Reverse-Offset Roll-to-Plate (RO-R2P) Printing

    Science.gov (United States)

    Mendoza, Kayna Lee; Ortega, Ada; Kim, Nam Soo

    2015-03-01

    Reverse-offset roll-to-plate printing has become increasingly popular in the printing industry because of the ease with which the printing process can be manipulated to achieve a high-resolution pattern with line widths as narrow as 5 μm with precision and accuracy. The printing procedure involves three stages, and a roller is required to transfer ink from each stage. The substrates used throughout this experiment were chosen by measuring their contact angles ( θ) and using them in accordance with the sequence: θ (Stage 1) > θ (roller) > θ (Stage 2) and θ (Stage 3). An ultraviolet (UV) light-emitting diode (LED)-curable ink was used during the printing process; however, the pristine solution of this ink was unsuitable for printing a final pattern on the substrate because of its viscosity. Diluting the solution of the UV LED-curable ink with 40% CH3OH resulted in reduced viscosity. The original solution had a viscosity of approximately 40.7 cP whereas that of the diluted solution was approximately 25 cP. The two solutions behaved as non-Newtonian, dilatant, shear-thickening fluids. The UV LED-curable ink solutions, both dilute and non-dilute, were successfully printed by use of an inkjet printer and three-dimensional printing methods.

  20. Curability of cancer by radiotherapy and chemotherapy, including in neuraxial neoplasms

    Directory of Open Access Journals (Sweden)

    Jalali Rakesh

    2009-01-01

    Full Text Available In the October of 1996, Lance Armstrong, celebrated cyclist and one of the greatest athletes the world has ever seen, at the age of 24, was diagnosed with metastatic testicular cancer with disease having already spread to his abdomen, lungs and brain. Lance underwent four cycles of chemotherapy, actually the pretty standard one, pioneered at the Indiana University and not only did he get completely cured of his cancer, he remains extremely well till date, 12 years later. He sure did have a few adverse effects during those cycles of chemotherapy in the form of nausea, vomiting, weakness and fall in blood count but he knew and experienced them only for a short transient time and emerged triumphant and strong. In fact, he went on to win six awe-inspiring and incredible successive Tours de France victories from 1999-2005, one of the most grueling sporting events testing the endurance of the very fittest. After his retirement, he has been so inspired that he has completely devoted himself to educate people about the common myths about cancer, and promised to raise awareness and generate money for furthering research into surgery, radiation therapy and chemotherapy for cancer through his foundation. He says "I am indebted to the doctors, nurses and medicine and would want to pay them back for all their energy and caring." In his successful journey of overcoming cancer, he captures the essence of its treatment so well by declaring "Pain is temporary, it may last a minute, or an hour, or a day, or a year, but eventually, it will subside and something else will take its place. If I quit, however, it will last forever".

  1. Study of coatings for improved fire and decay resistance of mine timbers

    Science.gov (United States)

    Baum, B.

    1977-01-01

    The purpose of this program was to find a fire- and rot-retardant polymer/fungicide reaction product for coating mine timbers. Fire-retardant polymers were screened as films and coatings on fir wood. Curable polyimide appeared to be flame retardant and evolved a minimum of fumes when exposed to a flame. Several organic and metal, low toxicity, fungicides were reacted with the polyimide in-situ on the wood. These coated samples were screened for fungus resistance. All formulations rated well - even the polyimide film without additives was fungicidal. The fir wood control itself resisted internal damage during the ten weeks of fungus exposure. A more severe test for fungus resistance will be required.

  2. Interpenetrating phase ceramic/polymer composite coatings: Fabrication and characterization

    Science.gov (United States)

    Craig, Bradley Dene

    The goals of this thesis research were to fabricate interpenetrating phase composite (IPC) ceramic/polymer coatings and to investigate the effect of the interconnected microstructure on the physical and wear properties of the coatings. IPC coatings with an interpenetrating phase microstructure were successfully fabricated by first forming a porous ceramic with an interconnected microstructure using a chemical bonding route (mainly reacting alpha-alumina (0.3 mum) with orthophosphoric acid to form a phosphate bond). Porosity within these ceramic coatings was easily controlled between 20 and 50 vol. % by phosphoric acid addition, and was measured by a new porosity measurement technique (thermogravimetric volatilization of liquids, or TVL) which was developed. The resulting ceramic preforms were infiltrated with a UV and thermally curable cycloaliphatic epoxide resin and cured. This fabrication route resulted in composite coatings with thicknesses ranging from ˜1mum to 100 mum with complete filling of open pore space. The physical properties of the composite coatings, including microhardness, flexural modulus and wear resistance, were evaluated as a function of processing variables, including orthophosphoric acid content and ceramic phase firing temperature, which affected the microstructure and interparticulate bonding between particles in the coatings. For example, microhardness increased from ˜30 on the Vicker's scale to well over 200 as interparticulate bonding was increased in the ceramic phase. Additionally, Taber wear resistance in the best TPC coatings was found to approach that of fully-densified alumina under certain conditions. Several factors were found to influence the wear mechanism in the IPC coating materials. Forming strong connections between ceramic particles led to up to an order of magnitude increase in the wear resistance. Additionally, coating microhardness and ceramic/polymer interfacial strength were studied and found to be important in

  3. Metal flame spray coating protects electrical cables in extreme environment

    Science.gov (United States)

    Brady, R. D.; Fox, H. A.

    1967-01-01

    Metal flame spray coating prevents EMF measurement error in sheathed instrumentation cables which are externally attached to cylinders which were cooled on the inside, but exposed to gamma radiation on the outside. The coating provides a thermoconductive path for radiation induced high temperatures within the cables.

  4. Microencapsulation of Self Healing Agents for Corrosion Control Coatings

    Science.gov (United States)

    Jolley, S. T.; Li, W.; Buhrow, J. W.; Calle, L. M.

    2011-01-01

    Corrosion, the environmentally induced degradation of materials, is a very costly problem that has a major impact on the global economy. Results from a 2-year breakthrough study released in 2002 by the U.S. Federal Highway Administration (FHWA) showed that the total annual estimated direct cost associated with metallic corrosion in nearly every U.S. industry sector was a staggering $276 billion, approximately 3.1% of the nation's Gross Domestic Product (GOP). Corrosion protective coatings are widely used to protect metallic structures from the detrimental effects of corrosion but their effectiveness can be seriously compromised by mechanical damage, such as a scratch, that exposes the metallic substrate. The incorporation of a self healing mechanism into a corrosion control coating would have the potential to significantly increase its effectiveness and useful lifetime. This paper describes work performed to incorporate a number of microcapsule-based self healing systems into corrosion control coatings. The work includes the preparation and evaluation of self-healing systems based on curable epoxy, acrylate, and siloxane resins, as well as, microencapsulated systems based on passive, solvent born, healing agent delivery. The synthesis and optimization of microcapsule-based self healing systems for thin coating (less than 100 micron) will be presented.

  5. Mathematical modeling of photoinitiated coating degradation: Effects of coating glass transition temperature and light stabilizers

    DEFF Research Database (Denmark)

    Kiil, Søren; G.de With, R.A.T.M.Van Benthem

    2013-01-01

    A mathematical model, describing coating degradation mechanisms of thermoset coatings exposed to ultraviolet radiation and humidity at constant temperature, was extended to simulate the behavior of a coating with a low glass transition temperature. The effects of adding light stabilizers (a UV...... absorber and a radical scavenger) to the coating were also explored. The extended model includes photoinitiated oxidation reactions, intrafilm oxygen permeability, water absorption and diffusion, reduction of crosslink density, absorption of ultraviolet radiation, a radical scavenger reaction......, and simulates the transient development of an oxidation zone. Simulations are in good agreement with experimental data for a fast degrading epoxy-amine coating with a glass transition temperature of −50°C. It was found that the degradation rate of the non-stabilized coating was influenced significantly...

  6. Optical coatings for laser fusion applications

    Energy Technology Data Exchange (ETDEWEB)

    Lowdermilk, W.H.; Milam, D.; Rainer, F.

    1980-04-24

    Lasers for fusion experiments use thin-film dielectric coatings for reflecting, antireflecting and polarizing surface elements. Coatings are most important to the Nd:glass laser application. The most important requirements of these coatings are accuracy of the average value of reflectance and transmission, uniformity of amplitude and phase front of the reflected or transmitted light, and laser damage threshold. Damage resistance strongly affects the laser's design and performance. The success of advanced lasers for future experiments and for reactor applications requires significant developments in damage resistant coatings for ultraviolet laser radiation.

  7. 纳米二氧化钛改性光固化树脂的研究%Study on nano-titanium dioxide modified UV-curable resin

    Institute of Scientific and Technical Information of China (English)

    张莹莹; 段玉岗; 李涤尘; 康小青

    2012-01-01

    The nano-TiO2 dispersed in propylene glycol monomethyl ether acetate(PMA) was used as additive to modify the UV-curable SPR4000 resin for stereolithography(SL).The properties of modified UV-curable resins were investigated by the testings of acid value,molecular weight,IR,DSC,TG rheology,mechanical property and thermal property of the modified resin and the cured product.The distribution of nano-TiO2 in UV-curable resin was observed by SEM.The rescult showed that the resin with mass fraction of liquid nano-TiO2 0.75% had the optimium mechanical properties and the tensile strength,impact strength and flexural strength were increased by 15.25%,41.35% and 41.75%,respectively.The heat resistance was also improved.The problem of dispersion stability of nano-TiO2 in UV-curable resin was solved by the addtion of nano-TiO2 PMA dispersion.The curing rate and crosslink density of UV-curable resin were ensured for meeting the production process and the mechanical properties of UV-curable resin were improved.%以纳米TiO2的丙二醇甲醚醋酸酯(PMA)分散液为添加剂改性激光快速成型用光固化树脂SPR4000,通过对树脂及固化物的酸值、分子质量、IR、DSC、热重分析、流变性及力学和热性能测试等研究了改性后光固化树脂的性能,并用扫描电镜对纳米TiO2在树脂中的分散情况进行了观察。结果表明添加的二氧化钛质量分数为0.75%时,体系力学性能最好,拉伸强度提高15.25%,冲击强度提高41.35%,弯曲强度提高41.75%,耐热性也有所提高。纳米二氧化钛PMA分散液的加入解决了纳米二氧化钛在树脂中的分散稳定性问题,保证了树脂体系的固化速度及交联密度,满足了制作工艺,提高了光固化树脂SPR4000的力学性能。

  8. 聚乙烯基光固化树脂的制备及其应用研究%Preparation and Application of UV Curable Polyethylene Resin

    Institute of Scientific and Technical Information of China (English)

    庞来兴; 洪小云; 李志云

    2016-01-01

    A well-defined UV-curable linear polyethylene resin with low molecular weight and end hydroxyl functional was synthesized by chain shuttling ethylene polymerization with 2,6-bis[1-(2,6-diisopropylphenylimino) ethyl] pyridyl iron ( II) dichloride as catalyst and acrylate capped reaction. NMR and IR analysis showed that the two structures obtained were UV curable modified polyethylene resin. As an additive in the UV-curable formulation, the resin can increase the amount matting agent in the formulation in an amount to some extent.%基于2,6-二甲基吡啶亚胺铁催化体系催化乙烯链穿梭聚合制备端羟基聚乙烯树脂;进行羟基丙烯酸酯的封端反应,赋予聚乙烯树脂紫外光固化活性。研究了改性聚乙烯树脂作为主体树脂及添加助剂应用于光固化涂料配方中进行研究。核磁及红外分析表明,获得两种结构明确的可紫外光固化改性聚乙烯树脂。通过光固化涂料配方研究表明,可紫外光固化聚乙烯树脂的光固化涂层光泽度较低,可作为哑光树脂使用。

  9. Method for emissivity measurement of semitransparent coatings at ambient temperature

    OpenAIRE

    Petra Honnerová; Jiří Martan; Zdeněk Veselý; Milan Honner

    2017-01-01

    Coatings deposited on a material surface are effective way of changing its surface properties. For increasing or decreasing radiation heat transfer, coatings with high or low emissivity are used. Measurement of spectral emissivity is a fundamental step to effective use of coatings for this application. Up to now the measurement methods are focused on bulk samples and mainly opaque ones. Here we present a method enabling measurement of emissivity of semitransparent coating itself, although it ...

  10. HYDROTHERMALLY SELF-ADVANCING HYBRID COATINGS FOR MITIGATING CORROSION OF CARBON STEEL.

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA, T.

    2006-11-22

    Hydrothermally self-advancing hybrid coatings were prepared by blending two starting materials, water-borne styrene acrylic latex (SAL) as the matrix and calcium aluminate cement (CAC) as the hydraulic filler, and then their usefulness was evaluated as the room temperature curable anti-corrosion coatings for carbon steel in CO{sub 2}-laden geothermal environments at 250 C. The following two major factors supported the self-improving mechanisms of the coating during its exposure in an autoclave: First was the formation of a high temperature stable polymer structure of Ca-complexed carboxylate groups containing SAL (Ca-CCG-SAL) due to hydrothermal reactions between SAL and CAC; second was the growth with continuing exposure time of crystalline calcite and boehmite phases coexisting with Ca-CCG-SAL. These two factors promoted the conversion of the porous microstructure in the non-autoclaved coating into a densified one after 7 days exposure. The densified microstructure not only considerably reduced the conductivity of corrosive ionic electrolytes through the coatings' layers, but also contributed to the excellent adherence of the coating to underlying steel' s surface that, in turn, retarded the cathodic oxygen reduction reaction at the corrosion site of steel. Such characteristics including the minimum uptake of corrosive electrolytes by the coating and the retardation of the cathodic corrosion reaction played an important role in inhibiting the corrosion of carbon steel in geothermal environments.

  11. Protective Coatings

    Science.gov (United States)

    1980-01-01

    General Magnaplate Corporation's pharmaceutical machine is used in the industry for high speed pressing of pills and capsules. Machine is automatic system for molding glycerine suppositories. These machines are typical of many types of drug production and packaging equipment whose metal parts are treated with space spinoff coatings that promote general machine efficiency and contribute to compliance with stringent federal sanitation codes for pharmaceutical manufacture. Collectively known as "synergistic" coatings, these dry lubricants are bonded to a variety of metals to form an extremely hard slippery surface with long lasting self lubrication. The coatings offer multiple advantages; they cannot chip, peel or be rubbed off. They protect machine parts from corrosion and wear longer, lowering maintenance cost and reduce undesired heat caused by power-robbing friction.

  12. Graphene Coatings

    DEFF Research Database (Denmark)

    Stoot, Adam Carsten; Camilli, Luca; Bøggild, Peter

    2014-01-01

    Owing to its remarkable electrical and mechanical properties, graphene has been attracting tremendous interest in materials science. In particular, its chemical stability and impermeability make it a promising protective membrane. However, recent investigations reveal that single layer graphene...... cannot be used as a barrier in the long run, due to galvanic corrosion phenomena arising when oxygen or water penetrate through graphene cracks or domain boundaries. Here, we overcome this issue by using a multilayered (ML) graphene coating. Our lab- as well as industrial-scale tests demonstrate that ML...... that graphene can still be a relevant candidate for thin coatings....

  13. Curability of Multiple Myeloma

    Directory of Open Access Journals (Sweden)

    Raymond Alexanian

    2012-01-01

    Full Text Available Among 792 patients with multiple myeloma treated from 1987 to 2010 and assessed after 18 months, there were 167 patients with complete remission. For those 60 patients treated between 1987–1998 and with long followup, the latest relapse occurred after 11.8 years, so that 13 patients have remained in sustained complete remission for longer than 12 years (range 12–22 years. These results suggest that 3% of all patients treated during that period may be cured of multiple myeloma. In addition to immunofixation, more sensitive techniques for the detection of residual disease should be applied more consistently in patients with apparent complete remission in order to identify those with potential cure.

  14. Study on visible-light-curable polycarprolactone and poly(ethylene glycol) diacrylate for LCD-projected maskless additive manufacturing system

    Science.gov (United States)

    Cheng, Yih-Lin; Kao, Hao-Lun

    2015-09-01

    Photopolymers have been applied in many Additive Manufacturing (AM) systems and mostly are cured by UV light. Biodegradable photo-curable polymers are very limited and are not commercially available. DLP-projected maskless AM systems become more and more popular nowadays, but its working area is limited if the part resolution is required. For larger working envelope purpose, liquid crystal display (LCD) panel has great potentials, and LCD's resolution has been improved significantly in the past few years due to the smart phone application. Therefore, in this research, LCD panel is used to replace DLP for a maskless AM system to cure biodegradable materials, Polycarprolactone (PCL) and Poly(ethylene glycol) diacrylate (PEG-DA). Due to the characteristics of LCD panel, the material systems should be sensitive and photo-polymerized in visible-light range, particularly in RGB. In this study, various percentages of visiblelight photoinitiator, Irgacure 784, in the material systems were investigated. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were utilized to characterize cured biomaterials. Because of the use of photoinitiator, the biocompatibility of the cured materials was also concerned, and hence, MTT assay tests were performed. The preliminary tests of fabrication, using the LCD-projected maskless AM system, cured grid patterns to illustrate the feasibility. The visible-light-curable PCL and PEG-DA will be able to be adopted in tissue engineering scaffold applications in the future.

  15. Optimization of UV-LED curable printing material for applications in direct writing systems: Inkjet, reverse offset, and micro dispensing GPD

    Science.gov (United States)

    Varela, Ada Judith Ortega

    The quality of a product fabricated by direct writing methods will depend greatly on the properties of the printing material and its compatibility with the printing process. Although multiple advances in developing printing inks and pastes with novel properties are being made, the potential those can bring to electronics is hindered by their stability and performance during the printing process. In this study a UV-LED curable acrylic material was used to test the optimization of inks and pastes for three of the most common direct writing systems: Piezo-type Inkjet, Reverse Offset Roll to Plate, and Micro Deposition. The viscosity of the photosensitive acrylic matrix was controlled by either the addition of diluents or electronically functional reinforcement material. The contact angle of the optimized solutions on 16 different Polyester, Polyimide, and Paper films was observed. Solutions with larger contact angles showed better line definition for the Inkjet and the Micro Dispense systems. In addition to the contact angle differential, the rheological properties showed to be a determinant factor for the feasibility of a solution to undergo the reverse offset printing process. The UV curable acrylic demonstrated electrical conductivity when 2% (wt.) MWCNT were ultrasonically mixed in the matrix and then cured with a 385nm wavelength for 3 seconds. Only the micro deposition system was capable of printing the acrylic-MWCNT paste and the relationship between the contact angle, pattern accuracy, substrate selection, and electrical conductivity, was determined.

  16. 木器涂料改性的新进展%New Progress of Wooden Ware Coatings Modified

    Institute of Scientific and Technical Information of China (English)

    刘国杰

    2012-01-01

    主要阐述了新材料和纳米技术对重要木器涂料改性研究的一些新进展,重点介绍纳米技术对水性和UV固化木器涂料的复合改性,以及溶胶-凝胶技术制备无机-有机纳米复合涂膜提高木材抗性的研究。%This paper mainly narrates some new progresses of the modification search of key wooden ware coatings by new materials and through nano technology, focusing on the complex modification of water-borne and UV curable wooden ware coatings through nano technology and the preparation research of inorganic organic nanocomposite coatings to improve the resistance of wood materials through sol-gel technology.

  17. 光/湿双固化聚氨酯热熔胶的制备与性能研究%Study on preparation and properties of UV/moisture dual curable polyurethane hot melt adhesive

    Institute of Scientific and Technical Information of China (English)

    蔡海元; 林星; 朱成伟; 林中祥

    2012-01-01

    以多元醇、异氰酸酯、含羟基丙烯酸酯和光引发剂等为原料,制备了PET(聚酯)基材粘接用光/湿双固化PU(聚氨酯)-PUA(聚氨酯丙烯酸酯)型反应性HMA(热熔胶).研究结果表明:该HMA中同时含有可光固化基团(C=C)和可湿固化基团(-NCO);当n(C=C)∶n(-NCO)=20∶ 80、w(复合光引发剂)=1.5%~2.0%和引入甲基丙烯酸羟乙酯(HEMA)时,相应HMA具有较高的初始强度和最终强度;光/湿双固化HMA的透明度高于湿固化HMA,说明UV固化是增加光/湿双固化HMA透明度的主要原因.%With polyol, isocyanate , hydroxyl - containing acrylate and photoinitiator as raw materials, an UV/moisture dual curable PU-PUA(polyurethane-polyurethane acrylate) type reactive HMA(hot melt adhesive) was made for bonding PET (polyester) base material. The research results showed that the HMA had both UV eurable group(C=C) and moisture curable group(-NCO). The corresponding HMA had higher initial strength and ultimate strength when molar ratio of n(C=C):n(-NCO) was 20:80, mass fraction of composite photoinitiator was 1.5%-2.0%,and hydroxylethyl methacrylate(HEMA) was introduced into system. The UV curable was main reason ■ of enhancing transparency of UV/moisture dual curable HMA because transparency of UV/moisture dual curable HMA was higher than that of moisture curable HMA.

  18. Model-based analysis of photoinitiated coating degradation under artificial exposure conditions

    DEFF Research Database (Denmark)

    Kiil, Søren

    2012-01-01

    Coating degradation mechanisms of thermoset coatings exposed to ultraviolet radiation and humidity at constant temperature are investigated. The essential processes, photoinitiated oxidation reactions, intrafilm oxygen permeability, water absorption and diffusion, reduction of crosslink density...

  19. Intumescent Coatings as Fire Retardants

    Science.gov (United States)

    Parker, J. A.; Fohlen, G. M.; Sawko, P. M.; Fish, R. H.

    1970-01-01

    The development of fire-retardant coatings to protect surfaces which may be exposed to fire or extreme heat is a subject of intense interest to many industries. A fire-retardant paint has been developed which represents a new chemical approach for preparing intumescent coatings, and potentially, is very important to fire-prevention authorities. The requirements for a superior coating include ease of application, suitability to a wide variety of surfaces and finishes, and stability over an extended period of time within a broad range of ambient temperature and humidity conditions. These innovative coatings, when activated by the heat of a fire, react to form a thick, low-density, polymeric coating or char layer. Water vapor and sulphur dioxide are released during the intumescent reaction. Two fire-protection mechanisms thus become available: (1) the char layer retards the flow of heat, due to the extremely low thermal conductivity; and (2) water vapor and sulfur dioxide are released, providing fire quenching properties. Still another mechanism functions in cases where the char, by virtue of its high oxidation resistance and low thermal conductivity, reaches a sufficiently high temperature to re-radiate much of the incident heat load. The coatings consist of dispersions of selective salts of a nitro-amino-arornatic compound. Specifically, para-nitroaniline bisulfate and the ammonium salt of para-nitroaniline-ortho sulphuric acid (2-amino-5-nitrobenzenesulphuric acid) are used. Suitable vehicles are cellulose nitrate of lacquer grade, a nitrite-phenolic modified rubber, or epoxy-polysulfide copolymer. Three separate formulations have been developed. A solvent is usually employed, such as methylethyl ketone, butyl acetate, or toluene, which renders the coatings suitably thin and which evaporates after the coatings are applied. Generally, the intumescent material is treated as insoluble in the vehicle, and is ground and dispersed in the vehicle and solvent like an

  20. Hybrid Organic/Inorganic Coatings Through Dual-Cure Processes: State of the Art and Perspectives

    Directory of Open Access Journals (Sweden)

    Giulio Malucelli

    2016-03-01

    Full Text Available This paper reviews the current state of the art related to the synthesis and characterization of hybrid organic-inorganic (O/I coatings obtained through the exploitation of dual-cure processes, which involve a photo-induced polymerization followed by a thermal treatment: this latter allows the occurrence of sol-gel reactions of suitable alkoxy precursors already embedded in the UV-curable system. After a brief introduction on hybrid organic-inorganic coatings, the first part of the review is focused on the design and feasibility issues provided by the dual-cure method, emphasizing the possibility of tuning the structure of the final hybrid network on the basis of the composition of the starting liquid mixture. Then, some recent examples of hybrid organic-inorganic networks are thoroughly described, showing their potential advances and the application fields to which they can be addressed.

  1. Development and in Vitro Characterization of Photochemically Crosslinked Polyvinylpyrrolidone Coatings for Drug-Coated Balloons

    Directory of Open Access Journals (Sweden)

    Svea Petersen

    2013-12-01

    Full Text Available Polyvinylpyrrolidone (PVP is a conventionally applied hydrophilic lubricious coating on catheter-based cardiovascular devices, used in order to ease movement through the vasculature. Its use as drug reservoir and transfer agent on drug-coated balloons (DCB is therefore extremely promising with regard to the simplification of its approval as a medical device. Here, we developed a PVP-based coating for DCB, containing paclitaxel (PTX as a model drug, and studied the impact of crosslinking via UV radiation on drug stability, wash off, and transfer during simulated use in an in vitro vessel model. We showed that crosslinking was essential for coating stability and needed to be performed prior to PTX incorporation due to decreased drug bioavailability as a result of photodecomposition and/or involvement in vinylic polymerization with PVP under UV radiation. Moreover, the crosslinking time needed to be carefully controlled. While short radiation times did not provide enough coating stability, associated with high wash off rates during DCB insertion, long radiation times lowered drug transfer efficiency upon balloon expansion. A ten minutes radiation of PVP, however, combined a minimized drug wash off rate of 34% with an efficient drug transfer of 49%, underlining the high potential of photochemically crosslinked PVP as a coating matrix for DCB.

  2. Elliptic Cylinder with Slotted Antenna Coated with Magnetic Metamaterials

    Directory of Open Access Journals (Sweden)

    A. K. Hamid

    2011-01-01

    Full Text Available The radiation properties of an axially slotted elliptic antenna coated with magnetic metamaterials are investigated. The fields inside and outside the dielectric coating are expressed in terms of the Mathieu functions. The boundary conditions at various surfaces are enforced using the orthogonality property of angular Mathieu functions. Numerical results are presented graphically for the radiation pattern, aperture conductance, and antenna gain for the TM case. It was found that a slotted antenna coated with magnetic metamaterials has more gain as well as lower side lobes compared to one coated with conventional dielectric or nonmagnetic metamaterials.

  3. EXPERIMENTAL STUDY ON SOLAR RADIATION OF COATINGS AND INFLUENCING ON ENERGY-SAVING OF BUILDINGS%涂料外饰面的太阳辐射性能及对建筑节能影响的试验研究

    Institute of Scientific and Technical Information of China (English)

    董海荣; 祁少明; 麻建锁; 张晓云

    2011-01-01

    外饰面材料的太阳辐射性能直接影响围护结构的热工性能,实际应用中掌握建筑外饰面材料的太阳辐射性能至关重要.通过介绍一种测试涂料外饰面太阳辐射吸收系数的间接方法,以及测试数据的分析和总结,说明涂料外饰面的太阳辐射性能对建筑节能的影响,为今后新型涂料的太阳辐射吸收系数的测试以及建筑外饰面材料的选择提供参考和指导.%The solar radiation of surface decoration materials affect the thermal performance of envelope of buildings directly.It is very important to master the solar radiation of surface decoration materials.This paper introduces a indirect method that can test solar radiation absorption coefficient of coatings, and explain influencing on energy-saving of buildings through the analysis and conclusion of the test data, which provides the reference for testing absorption coefficient of solar radiation of new coatings and the selection of external decorative materials in architectural design.

  4. Optical coatings: laser radiation damage. January 1975-July 1988 (Citations from the INSPEC: Information Services for the Physics and Engineering Communities data base). Report for January 1975-July 1988

    Energy Technology Data Exchange (ETDEWEB)

    1988-07-01

    This bibliography contains citations concerning theoretical aspects and experimental investigations of laser-induced damage of optical coatings. Damage thresholds of metal, dielectric, and metal-dielectric coating materials used in high-power lasers are discussed. The origin and morphology of damage, and the effects of coating processes and materials, and substrate materials on laser damage are included. Laser sources are also considered. (This updated bibliography contains 142 citations, 11 of which are new entries to the previous edition.)

  5. Throughput of Ultraviolet Nanoimprint in Pentafluoropropane Using Spin Coat Films under Thin Residual Layer Conditions

    Science.gov (United States)

    Hiroshima, Hiroshi; Suzuki, Kenta

    2012-06-01

    In UV nanoimprint, UV-curable resin is usually supplied as droplets, but, from the viewpoint of throughput, it is not the best approach in some cases. When the pattern density of a given layout can be regarded as uniform, UV-curable resin should be supplied as a film with a uniform thickness if no other critical problems occur. Fine line-and-space (L/S) patterns with widths of 45, 65, and 90 nm were successfully fabricated with a residual layer thickness of 20 nm by UV-NIL in pentafluoropropane (PFP) using a spin coat UV-curable resin, PAK-01, and the throughput of UV-NIL in PFP for the fabrication of such fine L/S patterns with a thin residual layer was investigated. The resin filling of UV-NIL in air was not completed in 15 s but that of UV-NIL in PFP was completed in 0.6 s. The filling speed of UV-NIL in PFP is 80 times higher than that of UV-NIL in air. This value is one order of magnitude larger for the fabrication of patterns with a width of 300 µm in our previous work, and the high-throughput process is presumably due to the large capillary pressure, which may be canceled out for UV-NIL in air, of fine grooves of the L/S patterns. Simulation revealed that a virtual imprint pressure of 2.2 MPa should be produced by the capillary pressure for UV-NIL in PFP. Simulations also revealed that the complete filling time is proportional to the square of the space width and that the resin filling would be completed in 0.1 s for a space width of less than 40 µm.

  6. 高温粘接加成型硅橡胶%An addition-curable silicone rubber with high temperature bonding properties

    Institute of Scientific and Technical Information of China (English)

    孔丽芬; 赵荆感

    2015-01-01

    介绍了一种在高温固化后能产生粘接性的加成型硅橡胶,比较了几种疏水型气相法白炭黑在该体系中的影响效果,结果发现H20较理想,且其添加量为12%时综合性能最好。%This paper introduced an addition-curable silicone rubber with high temperature adhesiveness by curing at high temperature. The effects of different hydrophobic fumed silica were analyzed. The results showed that the results of H20 silica was better and the comprehensive properties of silicone rubber were excellent when the content of H20 silica was 12%.

  7. 加成型有机硅灌封胶的粘接性能研究%Study on the Adhesive Properties of Addition Curable Silicone Encapsulant

    Institute of Scientific and Technical Information of China (English)

    吴向荣; 程宪涛; 靳利敏; 李清; 张利利

    2016-01-01

    以杂氮硅三环衍生物为增粘剂,制备了加成型粘接有机硅灌封胶。研究了导热填料用量、导热填料处理方式、增粘剂用量以及A值(硅氢基与硅乙烯基摩尔比)对加成型有机硅灌封胶粘接性能影响。结果表明,当导热填料硅微粉用量150份、导热填料硅微粉采用A171表面处理、增粘剂用量2.0份、A值1.4时,制备出对铝材、PA、ABS、PC粘接性能良好且导热、阻燃等综合性能优异的加成型有机硅灌封胶。%An addition curable silicone encapsulant with the adhesion properties has been prepared with carbasi-latrane derivative as tackifier. Effects of amounts of fillers,different modification methods,amounts of the tackifier and A value on the adhesion properties of silicone encapsulants were investigated. The results showed that,when the loading quartz powder was 150 phr,modified by A171,the loading tackifier was 2 phr and A value was 1. 4,the addition curable silicone encapsulants was prepared with excellent adhesion for aluminum, PA, ABS and PC, and with excellent comprehensive properties such as thermal conductivity,flame retardance.

  8. Corrosion resistant coating

    Science.gov (United States)

    Wrobleski, Debra A.; Benicewicz, Brian C.; Thompson, Karen G.; Bryan, Coleman J.

    1997-01-01

    A method of protecting a metal substrate from corrosion including coating a metal substrate of, e.g., steel, iron or aluminum, with a conductive polymer layer of, e.g., polyaniline, coating upon said metal substrate, and coating the conductive polymer-coated metal substrate with a layer of a topcoat upon the conductive polymer coating layer, is provided, together with the resultant coated article from said method.

  9. Coatings and Corrosion Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The mission of the Coatings and Corrosion Laboratory is to develop and analyze the effectiveness of innovative coatings test procedures while evaluating the...

  10. Light-cured Epoxy Acrylate Coatings Research%光固化环氧丙烯酸酯涂料的研究进展

    Institute of Scientific and Technical Information of China (English)

    王爱莲

    2013-01-01

    综述了光固化环氧丙烯酸酯涂料的合成和改性,其中改性主要是针对降低黏度,增加柔韧性,提高硬度、耐热、耐磨、阻燃等性能,展望了光固化技术的发展趋势。%The light-curable epoxy acrylate coatings synthesis and modification was elaborated, wherein the modified mainly for reducing viscosity, increase flexibility, improve the hardness and heat resistance, flame-retardant properties, the light-curing technology outlook trends.

  11. Low gloss UV-cured coatings for aircraft

    Science.gov (United States)

    Bowman, Mark; Muschar, Harry

    2014-12-09

    A method of applying a low gloss coating to a substrate such as the exterior surface of an aircraft is disclosed. The coating composition comprising a polyene, a polythiol, a flatting agent and a coloring pigment is applied to the substrate and given a first dosage of UV radiation followed by a second dosage in which the second dosage is greater than the first resulting in an ultralow gloss coating.

  12. Low gloss UV-cured coatings for aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, Mark; Muschar, Harry

    2014-12-09

    A method of applying a low gloss coating to a substrate such as the exterior surface of an aircraft is disclosed. The coating composition comprising a polyene, a polythiol, a flatting agent and a coloring pigment is applied to the substrate and given a first dosage of UV radiation followed by a second dosage in which the second dosage is greater than the first resulting in an ultralow gloss coating.

  13. Formation of Nanoscale Bioimprints of Muscle Cells Using UV-Cured Spin-Coated Polymers

    Directory of Open Access Journals (Sweden)

    Fahmi Samsuri

    2009-01-01

    Full Text Available We report a nanoscale replication method suitable for biological specimens that has potential in single cell studies and in formation of 3D biocompatible scaffolds. Earlier studies using a heat-curable polydimethylsiloxane (PDMS or a UV-curable elastomer introduced Bioimprint replication to facilitate cell imaging. However, the replicating conditions for thermal polymerization are known to cause cell dehydration during curing. In this study, a UV-cured methacrylate copolymer was developed for use in creating replicas of living cells and was tested on rat muscle cells. Bioimprints of muscle cells were formed by spin coating under UV irradiation. The polymer replicas were then separated from the muscle cells and were analyzed under an Atomic Force Microscope (AFM, in tapping mode, because it has low tip-sample forces and thus will not destroy the fine structures of the imprint. The new polymer is biocompatible with higher replication resolution and has a faster curing process than other types of silicon-based organic polymers such as PDMS. High resolution images of the muscle cell imprints showed the micro-and nanostructures of the muscle cells, including cellular fibers and structures within the cell membranes. The AFM is able to image features at nanoscale resolution with the potential for recognizing abnormalities on cell membranes at early stages of disease progression.

  14. Radiative Transport Modelling of Thermal Barrier Coatings

    Science.gov (United States)

    2017-03-24

    traveled by signal and reference beam photons) is the result of signal photons travelling a distance L through the sample . Since this distance L is related...performed in both tasks together for convenience . First, we briefly discuss the random walk model, since it is relevant in the discussion on both the...Figure 7, whereby a collinear low coherence beam (shown as a red arrow) is considered to be incident onto the sample at normal incidence to the surface

  15. High-Emissivity Coatings For High-Temperature Surfaces

    Science.gov (United States)

    Deininger, William D.; King, David Q.

    1988-01-01

    Plasma-sprayed coatings increase cooling by thermal radiation. Coating of zirconium diboride on tungsten or molybdenum increases emissivity of surface to more than 0.6 at 2,000 degree C. Applied by plasma-arc spraying after surface cleaned and roughened to ensure adhesion.

  16. Active coated nanoparticles: impact of plasmonic material choice

    DEFF Research Database (Denmark)

    Arslanagic, Samel; Ziolkowski, R.W.

    2011-01-01

    The near- and far-field properties of a number of active coated spherical nanoparticles excited by an electric Hertzian dipole at optical frequencies are investigated. Their enhanced, as well as reduced, radiation effects are demonstrated and compared.......The near- and far-field properties of a number of active coated spherical nanoparticles excited by an electric Hertzian dipole at optical frequencies are investigated. Their enhanced, as well as reduced, radiation effects are demonstrated and compared....

  17. Combinatorial materials research applied to the development of new surface coatings XV: an investigation of polysiloxane anti-fouling/fouling-release coatings containing tethered quaternary ammonium salt groups.

    Science.gov (United States)

    Majumdar, Partha; Crowley, Elizabeth; Htet, Maung; Stafslien, Shane J; Daniels, Justin; VanderWal, Lyndsi; Chisholm, Bret J

    2011-05-09

    As part of ongoing efforts aimed at the development of extensive structure−property relationships for moisture-curable polysiloxane coatings containing tethered quaternary ammonium salt (QAS) moieties for potential application as environmental friendly coatings to combat marine biofouling, a combinatorial/high-throughput (C/HT) study was conducted that was focused on four different compositional variables. The coatings that were investigated were derived from solution blends of a silanol-terminated polydimethylsiloxane (HO-PDMS-OH), QAS-functional alkoxysilane, and methyltriacetoxysilane. The compositional variables investigated were alkoxysilane functionality of the QAS-functional silane, chain length of the monovalent alkyl group attached to the QAS nitrogen atom, concentration of the QAS-functional alkoxysilane, and molecular weight of the HO-PDMS-OH. Of these variables, the composition of the alkoxysilane functionality of the QAS-functional silane was a unique variable that had not been previously investigated. The antifouling (AF) and fouling-release (FR) characteristics of the 24 unique coating compositions were characterized using HT assays based on three different marine microorganisms, namely, the two bacteria, Cellulophaga lytica and Halomonas pacifica, and the diatom, Navicula incerta. Coatings surfaces were characterized by surface energy, water contact angle hysteresis, and atomic force microscopy (AFM). A wide variety of responses were obtained over the compositional space investigated. ANOVA analysis showed that the compositional variables and their interactions significantly influenced AF/FR behaviors toward individual marine microorganisms. It was also found that utilization of the ethoxysilane-functional QASs provided enhanced AF character compared to coatings based on methoxysilane-functional analogues. This was attributed to enhanced surface segregation of QAS groups at the coating-air interface and confirmed by phase images using AFM.

  18. RADIATION STERILIZATION OF COCOA POWDERS

    Science.gov (United States)

    treatment on chocolate coatings, cocoa , and chocolate syrup. In all experimentation with gamma radiation, FLAVOR is the critical problem. At dosage...products of high fat content usually show marked changes in flavor. For example: cocoas , milk and bittersweet coatings, and cocoa utter. Inversely, no...off-flavors were detectable in chocolate syrups which have a low fat content. Some resistance to bloom can be achieved but at the loss of other

  19. In-line determination of the conversion in acrylate coatings after UV curing using near-infrared reflection spectroscopy

    Science.gov (United States)

    Scherzer, Tom; Müller, Sabine; Mehnert, Reiner; Volland, Arne; Lucht, Hartmut

    2005-07-01

    Near-infrared (NIR) reflection spectroscopy was used to determine the conversion of acrylic double bonds after UV photopolymerization. Quantitative analysis of the spectra was performed with chemometric methods using FTIR spectroscopy for calibration. Moreover, it was shown that the calibration of the PLS algorithm can also be performed directly to specific properties of the coatings such as their hardness which responds extremely sensitively even to small changes of the conversion. In-line monitoring of the conversion by NIR spectroscopy was carried out for acrylate coatings with a thickness of some micrometers applied to polymer foils and panels and for thick layers of UV-curable adhesives on the basis of acrylic hot-melts. The effect of changes of the irradiation dose, the emission spectrum of the UV source and other parameters on the conversion was studied.

  20. Quantitative Mapping of Mechanisms for Photoinitiated Coating Degradation

    DEFF Research Database (Denmark)

    Kiil, Søren

    2015-01-01

    This work concerns the mathematical modeling of photoinitiated coating degradation. Using experimental evidence available, some of the most importantassumptions underlying existing models for the rmoset coatings are analyzed and suggestions for further work provided. A modeling approach that can...... be used toimplement the various effects of water on the degradation mechanisms of cross-linked coatings is also presented and experiments to test the approach are suggested. Additionally, simulations with an existing degradation model for an epoxy–amine coating are used to map the influence of model...... parameters on the lag time (i.e., the time passing prior to the onset of erosion) and the stable erosion rate. The simulation results can be used in the optimization of UV radiation-induced intercoat adhesion losses, which are often observed in multilayer coating systems based on top coated epoxy coatings...

  1. Sterilizing radiation effects on selected polymers

    Energy Technology Data Exchange (ETDEWEB)

    Skiens, W. E.

    1979-03-01

    The mechanism of radiation effects and their industrial applications are discussed for the following classes of polymers: thermoplastics, thermosets, elastomers, films and fibers, and adhesives/coatings/potting compounds. 35 references, 3 tables. (DLC)

  2. Multi-layer coatings

    Energy Technology Data Exchange (ETDEWEB)

    Maghsoodi, Sina; Brophy, Brenor L.; Abrams, Ze' ev R.; Gonsalves, Peter R.

    2016-06-28

    Disclosed herein are coating materials and methods for applying a top-layer coating that is durable, abrasion resistant, highly transparent, hydrophobic, low-friction, moisture-sealing, anti-soiling, and self-cleaning to an existing conventional high temperature anti-reflective coating. The top coat imparts superior durability performance and new properties to the under-laying conventional high temperature anti-reflective coating without reducing the anti-reflectiveness of the coating. Methods and data for optimizing the relative thickness of the under-layer high temperature anti-reflective coating and the top-layer thickness for optimizing optical performance are also disclosed.

  3. Radiation therapy for unresected gastric lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Kataoka, Masaaki; Kawamura, Masashi; Kimura, Yoshiko; Itoh, Hisao; Tsuda, Takaharu; Komatsu, Akira; Hamamoto, Ken (Ehime Univ., Ehime (Japan). School of Medicine)

    1990-05-01

    Six consecutive patients with unresected gastric lymphoma which were treated by radiation therapy between November 1976 and March 1989 were reviewed. Radiation therapy was performed using involved fields, total radiation dosages of which ranged from 25.2 to 36 Gy (mean, 29.3 Gy). Five out of the 6 patients were treated with chemotherapy combined with radiation. Regimen of the chemotherapy was CHOP (cyclophophamide, adriamycin, vincristine and prednisone) in most cases. Three out of the 6 underwent probe laparotomy, but the tumors were diagnosed as unresectable due to locally invading the adjacent structures. They were treated by chemo-radiotherapy and 2 of them are surviving as of the present study (40 and 116 months). The other 3 patients were diagnosed as with clinical stage IV disease and 2 of them were successfully treated with chemo-radiotherapy (21 and 66 months, surviving). These data suggest that unresected gastric lymphomas, which are locally advanced or stage IV disease, are treated by chemo-radiotherapy with high curability without any serious complications. (author).

  4. Radiation Protection

    Science.gov (United States)

    ... EPA United States Environmental Protection Agency Search Search Radiation Protection Share Facebook Twitter Google+ Pinterest Contact Us Radiation Protection Document Library View and download EPA radiation ...

  5. 水溶性UV固化环氧预聚物的研究与制备%Study on Synthesis of Waterborne UV-Curable Epoxy Prepolymer

    Institute of Scientific and Technical Information of China (English)

    张亚军; 解一军

    2013-01-01

    An UV curable epoxy prepolymer(EA) containing more hydrophilic groups was synthesized with DMPA,acrylic acid(AA) and epoxy resin(E-51),which was reacted with maleic anhydride and neutralized with alkali to form a waterborne UV curable epoxy prepolymer(M-EA).The influence of reaction conditions such as reaction temperature,catalyst content on the reaction rate and the influence of the molar ratio of DMPA on the viscosity of the EA and water solubility of the product were disscussed.The results showed that the optimum reaction conditions of EA were as follows:DMPA∶ AA mole ratio was 3∶ 7,reaction temperature 100 ℃,BDMA 1.0%,reacting time 200 min.The optimum reaction temperature of MEA was 90 ℃/150 min.And finally prepolymer provided good comprehensive performance with water solubility 16.2%,film curing time 37 s and the hardness 2 H.%利用2,2-二羟甲基丙酸(DMPA)与丙烯酸(AA)、环氧树脂(E-51)进行反应,合成具有较多羟基基团的EA,再利用顺丁烯二酸酐(MA)与前述羟基反应引入尽可能多的亲水基团合成M-EA,中和成盐后制得水溶性UV固化环氧预聚物.讨论了反应温度、催化剂用量对反应速率的影响;DMPA含量对EA黏度、预聚物的水溶性以及涂膜固化时间的影响.并通过红外光谱(FT-IR)对EA结构进行表征.结果表明:合成EA的最佳工艺条件为:n(DMPA)∶n(AA)为3∶7,反应温度100℃,N,N-二甲基苄胺(BDMA)用量1%,反应时间为200 min.合成M-EA的反应温度为90℃,反应时间为150 min.获得的预聚物含水量为16.2%;涂膜光固化时间为37 s,硬度为2H,综合性能较好.

  6. Note: Strain sensitivity comparison between fiber Bragg gratings inscribed on 125 and 80 micron cladding diameter fibers, case study on the solidification monitoring of a photo-curable resin

    Energy Technology Data Exchange (ETDEWEB)

    Maccioni, E. [Dipartimento di Fisica, Università degli Studi di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Istituto Nazionale di Fisica Nucleare (INFN) sez. di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Morganti, M. [Istituto Nazionale di Fisica Nucleare (INFN) sez. di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Accademia Militare di Livorno, Viale Italia 72, 57100 Livorno (Italy); Brandi, F., E-mail: fernando.brandi@ino.it [Nanophysics Department, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova (Italy); Istituto Nazionale di Ottica (INO), Consiglio Nazionale delle Ricerche (CNR), Via G. Moruzzi 1, 56124 Pisa (Italy)

    2015-02-15

    The influence of fiber Bragg grating diameter when measuring strain is investigated and quantified. Two fiber Bragg gratings with bare cladding diameter of 125 μm and 80 μm are produced by excimer laser irradiation through a phase mask, and are used to simultaneously monitor the Bragg wavelength shift due to the strain produced by the solidification of a photo-curable resin during light exposure. It is found that the ratio of the measured strains in the two fiber Bragg gratings is close to the inverse ratio of the fiber’s cladding diameter. These results represent a direct simultaneous comparison between 125 μm and 80 μm diameter fiber Bragg grating strain sensors, and demonstrate the feasibility of strain measurements in photo-curable resins using bare 80 μm cladding diameter fiber Bragg gratings with an increased sensitivity and spatial resolution compared with standard 125 μm diameter fiber Bragg gratings.

  7. Note: strain sensitivity comparison between fiber Bragg gratings inscribed on 125 and 80 micron cladding diameter fibers, case study on the solidification monitoring of a photo-curable resin.

    Science.gov (United States)

    Maccioni, E; Morganti, M; Brandi, F

    2015-02-01

    The influence of fiber Bragg grating diameter when measuring strain is investigated and quantified. Two fiber Bragg gratings with bare cladding diameter of 125 μm and 80 μm are produced by excimer laser irradiation through a phase mask, and are used to simultaneously monitor the Bragg wavelength shift due to the strain produced by the solidification of a photo-curable resin during light exposure. It is found that the ratio of the measured strains in the two fiber Bragg gratings is close to the inverse ratio of the fiber's cladding diameter. These results represent a direct simultaneous comparison between 125 μm and 80 μm diameter fiber Bragg grating strain sensors, and demonstrate the feasibility of strain measurements in photo-curable resins using bare 80 μm cladding diameter fiber Bragg gratings with an increased sensitivity and spatial resolution compared with standard 125 μm diameter fiber Bragg gratings.

  8. Radiation Therapy

    Science.gov (United States)

    ... the area is stitched shut. Another treatment, called proton-beam radiation therapy , focuses the radiation on the ... after radiation treatment ends. Sore mouth and tooth decay. If you received radiation therapy to the head ...

  9. Radiation sickness

    Science.gov (United States)

    ... radiation. There are two basic types of radiation: ionizing and nonionizing. Nonionizing radiation comes in the form of light, radio waves, microwaves and radar. This kind of radiation usually ...

  10. Reflective Coating on Fibrous Insulation for Reduced Heat Transfer

    Science.gov (United States)

    Hass, Derek D.; Prasad, B. Durga; Glass, David E.; Wiedemann, Karl E.

    1997-01-01

    Radiative heat transfer through fibrous insulation used in thermal protection systems (TPS) is significant at high temperatures (1200 C). Decreasing the radiative heat transfer through the fibrous insulation can thus have a major impact on the insulating ability of the TPS. Reflective coatings applied directly to the individual fibers in fibrous insulation should decrease the radiative heat transfer leading to an insulation with decreased effective thermal conductivity. Coatings with high infrared reflectance have been developed using sol-gel techniques. Using this technique, uniform coatings can be applied to fibrous insulation without an appreciable increase in insulation weight or density. Scanning electron microscopy, Fourier Transform infrared spectroscopy, and ellipsometry have been performed to evaluate coating performance.

  11. Coating of pumps; coating af pumper

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Hans; Moritzen, J.; Thoegersen, Jeanette

    2005-11-15

    Coating of pumps is a quite new activity. For many years pipes and containers have been coated inside in order to avoid corrosion, but the technology has only been used inside pumps for the last ten years. The technology comes from USA and is originally developed in the space technology industry as an exceptionally durable and corrosion constant coating. The project is a further development of results found in a previous R and D project in which measurements were performed before and after coating two different installations. Both installations showed large efficiency improvements. This project supplements the theory behind losses in pumps with measurements on more pumps. (BA)

  12. Radiation dosimetry.

    OpenAIRE

    Cameron, J

    1991-01-01

    This article summarizes the basic facts about the measurement of ionizing radiation, usually referred to as radiation dosimetry. The article defines the common radiation quantities and units; gives typical levels of natural radiation and medical exposures; and describes the most important biological effects of radiation and the methods used to measure radiation. Finally, a proposal is made for a new radiation risk unit to make radiation risks more understandable to nonspecialists.

  13. UV固化剥离型PSA胶带的研制%Preparing UV-curable re-peelable PSA tapes

    Institute of Scientific and Technical Information of China (English)

    柳彬彬; 王旭辉; 杨春强

    2014-01-01

    以内含防静电粒子丙烯酸系胶粘剂(OCA)为基础,添加多官能团丙烯酸酯低聚物 TMPTM A ,2-羟基-2-甲基-1-苯基-1-丙酮(1173光引发剂)及苯二亚甲基二异氰酸酯交联剂 XDI ,制成UV光固化剥离型PSA胶带,考查了低聚物、光引发剂、交联剂的用量对胶带性能的影响,结果显示,ωTMPTMA =20%,ω1173光引发剂=6%,ω(XDI)=4%,干胶厚度15 m制成的胶带性能优异,前期粘着力高,经UV照射后粘着力低,易剥离,无污染,满足玻璃基材等透明材料的特殊加工工艺要求。%With the acrylic adhesive containing anti-static particles as the main material, trimethylolpropane triacrylate (TMPTMA) as the oligomer, 2-hydroxy-2-methylpropiophenone(1173) as the photoinitiator, xlylene diisocyanate (XDI) as the crosslinker and toluene as the solvent, a solvent-based acrylate PSA was prepared.And the influences of oligomer, photoinitiator and crosslinker were investigated on the PSA’s performances. The results showed that the PSA had good combination property and met the application requirements of transparent materials processing like glass,its initial adhesion was strong, and after UV-curing it had lower adhesion and no pollution and was easy peeling,when the contents bu weight of TMPTMA, photoinitiator 1173 and XDI were 20%, 6% and 4%, respectively,and the thickness of dry adhesive coat was 15 um.

  14. Continuous and scalable fabrication of bioinspired dry adhesives via a roll-to-roll process with modulated ultraviolet-curable resin.

    Science.gov (United States)

    Yi, Hoon; Hwang, Insol; Lee, Jeong Hyeon; Lee, Dael; Lim, Haneol; Tahk, Dongha; Sung, Minho; Bae, Won-Gyu; Choi, Se-Jin; Kwak, Moon Kyu; Jeong, Hoon Eui

    2014-08-27

    A simple yet scalable strategy for fabricating dry adhesives with mushroom-shaped micropillars is achieved by a combination of the roll-to-roll process and modulated UV-curable elastic poly(urethane acrylate) (e-PUA) resin. The e-PUA combines the major benefits of commercial PUA and poly(dimethylsiloxane) (PDMS). It not only can be cured within a few seconds like commercial PUA but also possesses good mechanical properties comparable to those of PDMS. A roll-type fabrication system equipped with a rollable mold and a UV exposure unit is also developed for the continuous process. By integrating the roll-to-roll process with the e-PUA, dry adhesives with spatulate tips in the form of a thin flexible film can be generated in a highly continuous and scalable manner. The fabricated dry adhesives with mushroom-shaped microstructures exhibit a strong pull-off strength of up to ∼38.7 N cm(-2) on the glass surface as well as high durability without any noticeable degradation. Furthermore, an automated substrate transportation system equipped with the dry adhesives can transport a 300 mm Si wafer over 10,000 repeating cycles with high accuracy.

  15. Optical coatings for solar cells and solar collectors. Citations from the Engineering Index data base

    Science.gov (United States)

    Carrigan, B.

    1980-01-01

    This bibliography of worldwide journal literature cites reports on materials and research for the development of selective coatings for solar energy conversion devices. These materials include types of coatings or covers used to reflect or transmit solar radiation in order to optimize solar conversion to heat or electricity. Most studies concern antireflection, thermal control, or reflective coatings. Coatings which act as optical filters are also covered. This updated bibliography contains 223 abstracts, 54 of which are new entries to the previous edition.

  16. Radiation Damage of Quartz Fibers

    CERN Document Server

    Hagopian, V

    1999-01-01

    Quartz fibers are used in high energy physics experiments as the active medium in high radiation area calorimetry. Quartz fibers are also used in the transmission of optical signals. Even though quartz does not damage by moderate amounts of irradiation, the clad of the fibers and the protective coating ( buffer) do damage reducing light transmission. Various types of quartz fibers have been irradiated and measured for light transmission. The most radiation hard quartz fibers are those with quartz clad and aluminum buffer.

  17. Electromagnetic and nuclear radiation detector using micromechanical sensors

    Science.gov (United States)

    Thundat, Thomas G.; Warmack, Robert J.; Wachter, Eric A.

    2000-01-01

    Electromagnetic and nuclear radiation is detected by micromechanical sensors that can be coated with various interactive materials. As the micromechanical sensors absorb radiation, the sensors bend and/or undergo a shift in resonance characteristics. The bending and resonance changes are detected with high sensitivity by any of several detection methods including optical, capacitive, and piezoresistive methods. Wide bands of the electromagnetic spectrum can be imaged with picoJoule sensitivity, and specific absorptive coatings can be used for selective sensitivity in specific wavelength bands. Microcantilevers coated with optical cross-linking polymers are useful as integrating optical radiation dosimeters. Nuclear radiation dosimetry is possible by fabricating cantilevers from materials that are sensitive to various nuclear particles or radiation. Upon exposure to radiation, the cantilever bends due to stress and its resonance frequency shifts due to changes in elastic properties, based on cantilever shape and properties of the coating.

  18. Low Earth Orbit Environmental Durability of Recently Developed Thermal Control Coatings

    Science.gov (United States)

    Jaworske, Donald A.

    2015-01-01

    The Materials International Space Station Experiment provided a means to expose materials and devices to the low Earth orbit environment on the exterior of the International Space Station. By returning the specimens to Earth after flight, the specimens could be evaluated by comparison with pre-flight measurements. One area of continuing interest is thermal control paints and coatings that are applied to exterior surfaces of spacecraft. Though traditional radiator coatings have been available for decades, recent work has focused on new coatings that offer custom deposition or custom optical properties. The custom deposition of interest is plasma spraying and one type of coating recently developed as part of a Small Business Innovative Research effort was designed to be plasma sprayed onto radiator surfaces. The custom optical properties of interest are opposite to those of a typical radiator coating, having a combination of high solar absorptance and low infrared emittance for solar absorber applications, and achieved in practice via a cermet coating. Selected specimens of the plasma sprayed coatings and the solar absorber coating were flown on Materials International Space Station Experiment 7, and were recently returned to Earth for post-flight analyses. For the plasma sprayed coatings in the ram direction, one specimen increased in solar absorptance and one specimen decreased in solar absorptance, while the plasma sprayed coatings in the wake direction changed very little in solar absorptance. For the cermet coating deployed in both the ram and wake directions, the solar absorptance increased. Interestingly, all coatings showed little change in infrared emittance.

  19. Study on preparation and performance of ultraviolet-curable active paste for electroless copper plating%紫外光固化化学镀铜活化浆料的制备及性能研究

    Institute of Scientific and Technical Information of China (English)

    曹权根; 陈世荣; 赖福东; 谢金平; 范小玲

    2015-01-01

    In order to prepare a silver-containing UV-curable active paste for electroless copper plating on the surface of PI (polyimide) thin film, the mixed potentialvs. time curves for electroless copper plating initiated by the active pastes obtained from different mass ratios of polyester acrylate to polyurethane acrylate were determined by electrochemical method, and the influence of the contents of silver nitrate and conductive carbon black on the adhesion and catalytic activity of the active paste and the conductivity of the copper deposit were studied. The surface morphology, structure, and silver distribution of the active paste and copper deposit were examined by scanning electron microscope (SEM), energy-dispersive X-ray spectrometer (EDS), and X-ray diffractometer (XRD). The active paste prepared with polyester acrylate and polyurethane acrylate at a mass ratio of 4 to 6 as composite prepolymers, conductive carbon black 10%, and AgNO3 7% was coated on PI thin film and then cured under UV irradiation. The copper deposit obtained by electroless copper plating for 10 min thereafter is fine-grained and compact with a 100% adhesion to the substrate and a square resistance of 0.046Ω/□.%为了在PI(聚酰亚胺)薄膜上制备一种含银的紫外光(UV)固化化学镀铜活化浆料,采用电化学方法测定了聚酯丙烯酸酯和聚氨酯丙烯酸酯不同质量比得到的活化浆料引发化学镀铜的混合电位–时间曲线,研究了硝酸银和导电炭黑含量对活化浆料的附着力、催化活性及铜镀层导电性的影响,通过扫描电镜(SEM)、X射线能谱仪(EDS)和X射线衍射仪(XRD)对活化浆料和铜镀层的表面形貌、结构以及Ag元素分布等进行了研究。以聚酯丙烯酸酯和聚氨酯丙烯酸酯按质量比为4∶6组成复合预聚体,导电炭黑和AgNO3的用量分别为10%和7%制备活化浆料,将其涂覆在PI薄膜上,UV固化后化学镀铜10 min,所得镀铜层颗粒细小、致

  20. Development of Advanced Thermal and Environmental Barrier Coatings Using a High-Heat-Flux Testing Approach

    Science.gov (United States)

    Zhu, Dongming; Miller, Robert A.

    2003-01-01

    The development of low conductivity, robust thermal and environmental barrier coatings requires advanced testing techniques that can accurately and effectively evaluate coating thermal conductivity and cyclic resistance at very high surface temperatures (up to 1700 C) under large thermal gradients. In this study, a laser high-heat-flux test approach is established for evaluating advanced low conductivity, high temperature capability thermal and environmental barrier coatings under the NASA Ultra Efficient Engine Technology (UEET) program. The test approach emphasizes the real-time monitoring and assessment of the coating thermal conductivity, which initially rises under the steady-state high temperature thermal gradient test due to coating sintering, and later drops under the cyclic thermal gradient test due to coating cracking/delamination. The coating system is then evaluated based on damage accumulation and failure after the combined steady-state and cyclic thermal gradient tests. The lattice and radiation thermal conductivity of advanced ceramic coatings can also be evaluated using laser heat-flux techniques. The external radiation resistance of the coating is assessed based on the measured specimen temperature response under a laser- heated intense radiation-flux source. The coating internal radiation contribution is investigated based on the measured apparent coating conductivity increases with the coating surface test temperature under large thermal gradient test conditions. Since an increased radiation contribution is observed at these very high surface test temperatures, by varying the laser heat-flux and coating average test temperature, the complex relation between the lattice and radiation conductivity as a function of surface and interface test temperature may be derived.

  1. Surfaces, Coatings and Protection

    Science.gov (United States)

    Ferguson, I. F.

    1982-08-01

    Plasma sprayed ceramics, sputter ion plating, and sol-gel ceramic protective coatings for nuclear reactors are discussed. The influence of such coatings on the behavior of reactor fuel elements is noted. The investigation of such coatings by diffraction methods is described. Laser and nuclear microprobes, scanning transmission electron microscopes, neutron scattering, and image analysis are summarized.

  2. Commercial Fastener Coatings Doerken

    Science.gov (United States)

    2010-06-01

    Phosphating* *partly recommended Dip Spinning Dipping Spraying Spin coating Conveyor oven box oven Inductive drying Pretreatment Coating Preheating...Curing Cooling Application Techniques - Dip Spin Coating Gurtbnd Cross BarTranspo" Band beiCifteiE Vo12one Vent llated Pre .Zone Cros~ Bar T ransrt

  3. PIT Coating Requirements Analysis

    Energy Technology Data Exchange (ETDEWEB)

    MINTEER, D.J.

    2000-10-20

    This study identifies the applicable requirements for procurement and installation of a coating intended for tank farm valve and pump pit interior surfaces. These requirements are intended to be incorporated into project specification documents and design media. This study also evaluates previously recommended coatings and identifies requirement-compliant coating products.

  4. Novel hybrid polymeric materials for barrier coatings

    Science.gov (United States)

    Pavlacky, Erin Christine

    Polymer-clay nanocomposites, described as the inclusion of nanometer-sized layered silicates into polymeric materials, have been widely researched due to significant enhancements in material properties with the incorporation of small levels of filler (1--5 wt.%) compared to conventional micro- and macro-composites (20--30 wt.%). One of the most promising applications for polymer-clay nanocomposites is in the field of barrier coatings. The development of UV-curable polymer-clay nanocomposite barrier coatings was explored by employing a novel in situ preparation technique. Unsaturated polyesters were synthesized in the presence of organomodified clays by in situ intercalative polymerization to create highly dispersed clays in a precursor resin. The resulting clay-containing polyesters were crosslinked via UV-irradiation using donor-acceptor chemistry to create polymer-clay nanocomposites which exhibited significantly enhanced barrier properties compared to alternative clay dispersion techniques. The impact of the quaternary alkylammonium organic modifiers, used to increase compatibility between the inorganic clay and organic polymer, was studied to explore influence of the organic modifier structure on the nanocomposite material properties. By incorporating just the organic modifiers, no layered silicates, into the polyester resins, reductions in film mechanical and thermal properties were observed, a strong indicator of film plasticization. An alternative in situ preparation method was explored to further increase the dispersion of organomodified clay within the precursor polyester resins. In stark contrast to traditional in situ polymerization methods, a novel "reverse" in situ preparation method was developed, where unmodified montmorillonite clay was added during polyesterification to a reaction mixture containing the alkylammonium organic modifier. The resulting nanocomposite films exhibited reduced water vapor permeability and increased mechanical properties

  5. Hard and superhard nanocomposite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Musil, J. [Univ. of West Bohemia, Plzen (Czech Republic). Dept. of Phys.

    2000-03-01

    This article reviews the development of hard coatings from a titanium nitride film through superlattice coatings to nanocomposite coatings. Significant attention is devoted to hard and superhard single layer nanocomposite coatings. A strong correlation between the hardness and structure of nanocomposite coatings is discussed in detail. Trends in development of hard nanocomposite coatings are also outlined. (orig.)

  6. Antibacterial polymer coatings.

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Mollye C.; Allen, Ashley N.; Barnhart, Meghan; Tucker, Mark David; Hibbs, Michael R.

    2009-09-01

    A series of poly(sulfone)s with quaternary ammonium groups and another series with aldehyde groups are synthesized and tested for biocidal activity against vegetative bacteria and spores, respectively. The polymers are sprayed onto substrates as coatings which are then exposed to aqueous suspensions of organisms. The coatings are inherently biocidal and do not release any agents into the environment. The coatings adhere well to both glass and CARC-coated coupons and they exhibit significant biotoxicity. The most effective quaternary ammonium polymers kills 99.9% of both gram negative and gram positive bacteria and the best aldehyde coating kills 81% of the spores on its surface.

  7. Vacuum plasma spray coating

    Science.gov (United States)

    Holmes, Richard R.; Mckechnie, Timothy N.

    1989-01-01

    Currently, protective plasma spray coatings are applied to space shuttle main engine turbine blades of high-performance nickel alloys by an air plasma spray process. Originally, a ceramic coating of yttria-stabilized zirconia (ZrO2.12Y2O3) was applied for thermal protection, but was removed because of severe spalling. In vacuum plasma spray coating, plasma coatings of nickel-chromium-aluminum-yttrium (NiCrAlY) are applied in a reduced atmosphere of argon/helium. These enhanced coatings showed no spalling after 40 MSFC burner rig thermal shock cycles between 927 C (1700 F) and -253 C (-423 F), while current coatings spalled during 5 to 25 test cycles. Subsequently, a process was developed for applying a durable thermal barrier coating of ZrO2.8Y2O3 to the turbine blades of first-stage high-pressure fuel turbopumps utilizing the enhanced NiCrAlY bond-coating process. NiCrAlY bond coating is applied first, with ZrO2.8Y2O3 added sequentially in increasing amounts until a thermal barrier coating is obtained. The enchanced thermal barrier coating has successfully passed 40 burner rig thermal shock cycles.

  8. Anticorrosive coatings: a review

    DEFF Research Database (Denmark)

    Sørensen, Per Aggerholm; Kiil, Søren; Dam-Johansen, Kim

    2009-01-01

    The main objective of this review is to describe some of the important topics related to the use of marine and protective coatings for anticorrosive purposes. In this context, "protective" refers to coatings for containers, offshore constructions, wind turbines, storage tanks, bridges, rail cars......, and petrochemical plants while "marine" refers to coatings for ballast tanks, cargo holds and cargo tanks, decks, and engine rooms on ships. The review aims at providing a thorough picture of state-of-the-art in anticorrosive coatings systems. International and national legislation aiming at reducing the emission...... of volatile organic compounds (VOCs) have caused significant changes in the anticorrosive coating industry. The requirement for new VOC-compliant coating technologies means that coating manufacturers can no longer rely on the extensive track record of their time-served products to convince consumers...

  9. Evaluation of HVOF coatings

    Directory of Open Access Journals (Sweden)

    Mariana Landová

    2016-07-01

    Full Text Available Attention in this paper is devoted to the evaluation of wear coatings deposited using HVOF technology (high velocity oxy-fuel. There were evaluated three types of coatings based on WC-Co (next only 1343, WC-Co-Cr (next only 1350 and Cr3C2-25NiCr (next only 1375. There was assessed adherence of coatings, micro hardness, porosity and the tribological properties of erosive, abrasive, adhesive and wear resistance of coatings in terms of cyclic thermal load. Thanks to wide variety of suitable materials and their combinations, the area of utilization thermally sprayed coatings is very broad. It is possible to deposit coatings of various materials from pure metals to special alloys. The best results in the evaluated properties were achieved at the coating with the label 1375.

  10. Beryllium coating on Inconel tiles

    Energy Technology Data Exchange (ETDEWEB)

    Bailescu, V.; Burcea, G.; Lungu, C.P.; Mustata, I.; Lungu, A.M. [Association EURATOM-MEC Romania, National Institute of Laser, Plasma and Radiation Physics, Bucharest (Romania); Rubel, M. [Alfven Laboratory, Royal Institute of Technology, Stockholm (Sweden); Coad, J.P. [Culham Science Centre, EURATOM-UKAEA Fusion Association, Abingdon, OX, Oxon (United Kingdom); Matthews, G.; Pedrick, L.; Handley, R. [UKAEA Fusion, Association Euratom-UKAEA, Culham Science and Engineering Centre, OX 3DB ABINGDON, Oxon (United Kingdom)

    2007-07-01

    Full text of publication follows: The Joint European Torus (JET) is a large experimental nuclear fusion device. Its aim is to confine and study the behaviour of plasma in conditions and dimensions approaching those required for a fusion reactor. The plasma is created in the toroidal shaped vacuum vessel of the machine in which it is confined by magnetic fields. In preparation for ITER a new ITER-like Wall (ILW) will be installed on Joint European Torus (JET), a wall not having any carbon facing the plasma [1]. In places Inconel tiles are to be installed, these tiles shall be coated with Beryllium. MEdC represented by the National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest and in direct cooperation with Nuclear Fuel Plant Pitesti started to coat Inconel tiles with 8 {mu}m of Beryllium in accordance with the requirements of technical specification and fit for installation in the JET machine. This contribution provides an overview of the principles of manufacturing processes using thermal evaporation method in vacuum and the properties of the prepared coatings. The optimization of the manufacturing process (layer thickness, structure and purity) has been carried out on Inconel substrates (polished and sand blasted) The results of the optimization process and analysis (SEM, TEM, XRD, Auger, RBS, AFM) of the coatings will be presented. Reference [1] Takeshi Hirai, H. Maier, M. Rubel, Ph. Mertens, R. Neu, O. Neubauer, E. Gauthier, J. Likonen, C. Lungu, G. Maddaluno, G. F. Matthews, R. Mitteau, G. Piazza, V. Philipps, B. Riccardi, C. Ruset, I. Uytdenhouwen, R and D on full tungsten divertor and beryllium wall for JET TIER-like Wall Project, 24. Symposium on Fusion Technology - 11-15 September 2006 -Warsaw, Poland. (authors)

  11. New insight into failure of resin-coated proppant consolidation

    Energy Technology Data Exchange (ETDEWEB)

    Dewprashad, B.; Nguyen, P. D.; Weaver, J. D.; Wardall, T.; Black, K. [Halliburton Energy Services Inc., TX (United States)

    1998-12-31

    The use of curable resin-coated proppants (RCPs) for controlling proppant flowback after hydraulic fracturing treatments and in screenless, fracpack completions is widespread. However,the cure kinetics of the RCP chosen for a particular application are generally ignored. This paper reviews the results of a study comparing the consolidation performance of RCPs with different cure kinetics under simulated treatment and downhole conditions. Techniques for determining RCPs cure kinetics are also described, including differential calorimetry (DSC), rock mechanical measurements, and scanning electron microscopy (SEM). Results of SEM analysis showed that in fast curing RCPs there was a decrease in the number of contact points between proppant grains, and a loss of consolidation strength when faster curing RCPs were exposed to fluids for various periods of time before onset of closures. The information helps to improve understanding the failure mechanisms of RCPs and provides guidelines for selecting the most appropriate RCP to be used in screenless completions where consolidations are expected to withstand production conditions of high flow rates and stress cycling. 8 refs., 15 figs.

  12. Combustion chemical vapor desposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States)

    1995-10-01

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings.

  13. Radiation Therapy

    Science.gov (United States)

    Radiation therapy is a cancer treatment. It uses high doses of radiation to kill cancer cells and stop them from ... half of all cancer patients receive it. The radiation may be external, from special machines, or internal, ...

  14. Radiation dosimetry

    CERN Document Server

    Hine, Gerald J; Hine, Gerald J

    1956-01-01

    Radiation Dosimetry focuses on the advancements, processes, technologies, techniques, and principles involved in radiation dosimetry, including counters and calibration and standardization techniques. The selection first offers information on radiation units and the theory of ionization dosimetry and interaction of radiation with matter. Topics include quantities derivable from roentgens, determination of dose in roentgens, ionization dosimetry of high-energy photons and corpuscular radiations, and heavy charged particles. The text then examines the biological and medical effects of radiation,

  15. Thermal Imaging Processes of Polymer Nanocomposite Coatings

    Science.gov (United States)

    Meth, Jeffrey

    2015-03-01

    Laser induced thermal imaging (LITI) is a process whereby infrared radiation impinging on a coating on a donor film transfers that coating to a receiving film to produce a pattern. This talk describes how LITI patterning can print color filters for liquid crystal displays, and details the physical processes that are responsible for transferring the nanocomposite coating in a coherent manner that does not degrade its optical properties. Unique features of this process involve heating rates of 107 K/s, and cooling rates of 104 K/s, which implies that not all of the relaxation modes of the polymer are accessed during the imaging process. On the microsecond time scale, the polymer flow is forced by devolatilization of solvents, followed by deformation akin to the constrained blister test, and then fracture caused by differential thermal expansion. The unique combination of disparate physical processes demonstrates the gamut of physics that contribute to advanced material processing in an industrial setting.

  16. The search for low photodesorption coatings

    Science.gov (United States)

    Foerster, C. L.; Korn, G.

    1991-08-01

    Low photo desorption (PSD) from surfaces of vacuum chambers increases the beam lifetime and reduces the cost of the pumping system of any storage ring. In compact rings where all radiated power (˜10 kW) is incident on a few meters only, low PSD and good thermal conductivity of photon absorbers are of particular importance. An experimental chamber in which one meter long bars can be exposed to white photon beam with 500 eV critical energy has been built and installed on the U10B beamline in the VUV ring at the NSLS. Several reference bars made of high purity copper and a TiN coating on copper have been measured. Subsequent runs will include gold coating on copper, aluminum (200 °C baked), hard carbon coating on copper and uncoated beryllium bars. In this paper the desorption coefficients will be measured and compared.

  17. Electromagnetics of active coated nano-particles

    DEFF Research Database (Denmark)

    Arslanagic, Samel

    2013-01-01

    This work reviews the fundamental properties of several spherical and cylindrical active coated nano-particles excited by their respective single and/or multiple sources of radiation at optical frequencies. Particular attention is devoted to the influence of the source location and orientation......, the optical gain constant and the nano-particle material composition on the electric and magnetic near fields, the power flow density, the radiated power as well as the directivities. Resonant as well as quasi-transparent states will be emphasized in the discussion....

  18. Surface coating for prevention of metallic seed migration in tissues.

    Science.gov (United States)

    Lee, Hyunseok; Lee, Won Seok; Park, Jong In; Son, Kwang-Jae; Park, Min; Bang, Young-bong; Choy, Young Bin; Ye, Sung-Joon

    2015-06-01

    In radiotherapy, metallic implants often detach from their deposited sites and migrate to other locations. This undesirable migration could cause inadequate dose coverage for permanent brachytherapy and difficulties in image-guided radiation delivery for patients. To prevent migration of implanted seeds, the authors propose a potential strategy to use a biocompatible and tissue-adhesive material called polydopamine. In this study, nonradioactive dummy seeds that have the same geometry and composition as commercial I-125 seeds were coated in polydopamine. Using scanning electron microscopy and x-ray photoelectron spectroscopy, the surface of the polydopamine-coated and noncoated seeds was characterized. The detachment stress between the two types of seeds and the tissue was measured. The efficacy of polydopamine-coated seed was investigated through in vitro migration tests by tracing the seed location after tissue implantation and shaking for given times. The cytotoxicity of the polydopamine coating was also evaluated. The results of the coating characterization have shown that polydopamine was successfully coated on the surface of the seeds. In the adhesion test, the polydopamine-coated seeds had 2.1-fold greater detachment stress than noncoated seeds. From the in vitro test, it was determined that the polydopamine-coated seed migrated shorter distances than the noncoated seed. This difference was increased with a greater length of time after implantation. The authors suggest that polydopamine coating is an effective technique to prevent migration of implanted seeds, especially for permanent prostate brachytherapy.

  19. Surface coating for prevention of metallic seed migration in tissues

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyunseok; Park, Jong In [Program in Biomedical Radiation Sciences, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, Won Seok; Park, Min [Interdisciplinary Program in Bioengineering, Seoul National University College of Engineering, Seoul 151-742 (Korea, Republic of); Son, Kwang-Jae [Hanaro Applications Research, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Bang, Young-bong [Advanced Institutes of Convergence Technology, Seoul National University, Suwon 443-270 (Korea, Republic of); Choy, Young Bin, E-mail: ybchoy@snu.ac.kr, E-mail: sye@snu.ac.kr [Interdisciplinary Program in Bioengineering, Seoul National University College of Engineering, Seoul 110-744 (Korea, Republic of); Department of Biomedical Engineering, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Institute of Medical and Biological Engineering, Medical Research Center, Seoul National University, Seoul 110-744 (Korea, Republic of); Ye, Sung-Joon, E-mail: ybchoy@snu.ac.kr, E-mail: sye@snu.ac.kr [Program in Biomedical Radiation Sciences, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 151-742 (Korea, Republic of); Advanced Institutes of Convergence Technology, Seoul National University, Suwon 443-270 (Korea, Republic of); Department of Radiation Oncology, Seoul National University Hospital, Seoul 110-744 (Korea, Republic of)

    2015-06-15

    Purpose: In radiotherapy, metallic implants often detach from their deposited sites and migrate to other locations. This undesirable migration could cause inadequate dose coverage for permanent brachytherapy and difficulties in image-guided radiation delivery for patients. To prevent migration of implanted seeds, the authors propose a potential strategy to use a biocompatible and tissue-adhesive material called polydopamine. Methods: In this study, nonradioactive dummy seeds that have the same geometry and composition as commercial I-125 seeds were coated in polydopamine. Using scanning electron microscopy and x-ray photoelectron spectroscopy, the surface of the polydopamine-coated and noncoated seeds was characterized. The detachment stress between the two types of seeds and the tissue was measured. The efficacy of polydopamine-coated seed was investigated through in vitro migration tests by tracing the seed location after tissue implantation and shaking for given times. The cytotoxicity of the polydopamine coating was also evaluated. Results: The results of the coating characterization have shown that polydopamine was successfully coated on the surface of the seeds. In the adhesion test, the polydopamine-coated seeds had 2.1-fold greater detachment stress than noncoated seeds. From the in vitro test, it was determined that the polydopamine-coated seed migrated shorter distances than the noncoated seed. This difference was increased with a greater length of time after implantation. Conclusions: The authors suggest that polydopamine coating is an effective technique to prevent migration of implanted seeds, especially for permanent prostate brachytherapy.

  20. Method for emissivity measurement of semitransparent coatings at ambient temperature.

    Science.gov (United States)

    Honnerová, Petra; Martan, Jiří; Veselý, Zdeněk; Honner, Milan

    2017-05-03

    Coatings deposited on a material surface are effective way of changing its surface properties. For increasing or decreasing radiation heat transfer, coatings with high or low emissivity are used. Measurement of spectral emissivity is a fundamental step to effective use of coatings for this application. Up to now the measurement methods are focused on bulk samples and mainly opaque ones. Here we present a method enabling measurement of emissivity of semitransparent coating itself, although it is deposited on a substrate. The method is based on measurement of transmittance and reflectance using an integration sphere system and Fourier transform infrared (FTIR) spectrometer for samples with two different coating thicknesses deposited on transparent substrates. Measured transmittance of the coating indicates spectral regions of potential emissivity differences using different substrates. From all the measured values, spectral emissivity can be characterized for different coating thicknesses. The spectral range of the method is from 2 μm to 20 μm. The measurement is done at ambient temperature enabling measurement of samples sensitive to heating like biomedical or nanocoatings. The method was validated on known bulk samples and an example of semitransparent coating measurement is shown on high-temperature high-emissivity coating.

  1. Electrospark deposition coatings

    Science.gov (United States)

    Sheely, W. F.

    1986-11-01

    Hard surfacing for wear resistant and low-friction coatings has been improved by means of advances in the computer controls in electronic circuitry of the electrospark deposition (ESD) process. coatings of nearly any electrically conductive metal alloy or cermet can be deposited on conductive materials. Thickness is usually two mils or less, but can be as high as 10 mils. ESD coatings can quadrupole cutting tool life.

  2. Advanced Multifunctional Coating

    Science.gov (United States)

    2011-08-17

    and UV durability of then current chrome free TT-P-2756 SPTC • Leverage APC technology into SPTC • Coating uses same fluoropolyurethane technology...as APC currently used on C-17 • Leverage recent advances in chrome free corrosion inhibitor technology • State of the art chrome free corrosion...coat exposed metal Aluminum Base Metal Original Finish System Aged APC Topcoat Conversion Coat Chromic Acid Anodize Aluminum Cladding Original Primer

  3. Radiation protection

    CERN Document Server

    CERN. Geneva

    2001-01-01

    This will be a simple explanation of the reasons why CERN has to be careful about radiation protections issues, a practical guide on how to recognize radiation dangers, the monitoring systems that make sure radiation levels are well tolerable norms, and a quick summary of what radiation levels mean in terms of personal risk.

  4. Oxide coating development

    Energy Technology Data Exchange (ETDEWEB)

    Stinton, D.P.

    1995-06-01

    Monolithic SiC heat exchangers and fiber-reinforced SiC-matrix composite heat exchangers and filters are susceptible to corrosion by alkali metals at elevated temperatures. Protective coatings are currently being developed to isolate the SiC materials from the corrodants. Unfortunately, these coatings typically crack and spall when applied to SiC substrates. The purpose of this task is to determine the feasibility of using a compliant material between the protective coating and the substrate. The low-modulus compliant layer could absorb stresses and eliminate cracking and spalling of the protective coatings.

  5. Superhard Nanocomposite Coatings

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The recent development in the field of nanocomposite coatings with good mechanical properties is critically reviewed in this paper. The design principle and materials selection for the nanocomposite coatings are introduced. Different methods for the preparation of superhard nanocomposite coatings are described with emphasis on the magnetron sputtering. Based on recent theoretical and experimental results regarding the appearance of superhardness in nanocomposite coating, lattice parameter changes, crystallite size, microstructure and morphology are reviewed in detail. Also emphasized are the mechanical properties (especially on hardness) and the ways by which the properties are derived.

  6. Modeling of nanoparticle coatings for medical applications

    CERN Document Server

    Haume, Kaspar; Solov'yov, Andrey

    2016-01-01

    Gold nanoparticles (AuNPs) have been shown to possess properties beneficial for the treatment of cancerous tumors by acting as radiosensitizers for both photon and ion radiation. Blood circulation time is usually increased by coating the AuNPs with poly(ethylene glycol) (PEG) ligands. The effectiveness of the PEG coating, however, depends on both the ligand surface density and length of the PEG molecules, making it important to understand the structure of the coating. In this paper the thickness, ligand surface density, and density of the PEG coating is studied with classical molecular dynamics using the software package MBN Explorer. AuNPs consisting of 135 atoms (approximately 1.4 nm diameter) in a water medium have been studied with the number of PEG ligands varying between 32 and 60. We find that the thickness of the coating is only weakly dependent on the surface ligand density and that the degree of water penetration increased when there is a smaller number of attached ligands.

  7. Comparative assessment of conventional and light-curable fluoride varnish in the prevention of enamel demineralization during fixed appliance therapy: a split-mouth randomized controlled trial.

    Science.gov (United States)

    Shah, Mandar; Paramshivam, Ganesh; Mehta, Anurag; Singh, Surjit; Chugh, Ankita; Prashar, Anil; Chugh, Vinay Kumar

    2017-05-13

    To evaluate the effects of single application of a conventional versus light-curable fluoride varnish (LCFV) on prevention of enamel demineralization during fixed orthodontic treatment over a 4 month period. The research was designed as a split-mouth, randomized control trial (RCT). Twenty-two patients requiring fixed orthodontic treatment with premolar extractions were included in the RCT. In each patient, two diagonal quadrants (i.e. upper right and lower left, or vice versa) were randomly assigned to receive conventional fluoride varnish or LCFV. After allocation of one intervention, the other diagonal quadrants received the second intervention. At specific time intervals, premolars were extracted and sectioned, and the demineralized lesion was assessed in each group. The primary outcome was demineralized enamel lesion depth (DELD) at the end of 45, 90, and 120 days. A simple complete randomization list using random allocation rule (restricted randomization) was computer generated to ensure homogeneity of application of conventional or LCFV to each contralateral quadrant in a split-mouth design. Allocation concealment was not employed. Blinding was done only for outcome assessor because of clinical limitations. Twenty-two patients with 88 teeth were enrolled in the trial. After excluding the drop-outs, primary analysis was performed on 66 teeth distributed among two interventional groups. Mean difference between DELD among two groups was 36.6 µm [95 per cent confidence interval (CI) 34.61-38.55] and 58.5 µm [95 per cent confidence interval (CI) 55.65-61.43] at 90 and 120 days, respectively. Cluster level analysis performed by Paired t-test showed that DELD was significantly higher (P fluoride varnish group at the end of 90 and 120 days as compared to LCFV group. No adverse effect was observed in any patient. Being a histologic study, the role of fluoride varnish could be assessed only for 4 months. The result of this study indicate that single application of

  8. Achieving cryogenic temperatures in deep space using a coating.

    Science.gov (United States)

    Youngquist, Robert C; Nurge, Mark A

    2016-03-15

    There is a current need to develop coatings that can reject more than 99% of the sun's irradiance to enable cryogenic storage and superconductor operation in space. Such a coating is proposed, composed of broadband scatterers on a metallic reflecting layer, yielding a surface that backscatters most of the solar spectrum yet still emits far-IR radiation. A model is presented with results, showing that a properly designed coating may potentially backscatter more than 99.9% of the sun's energy and allowing temperatures below 50 K to be achieved.

  9. Directive properties of active coated nano-particles

    DEFF Research Database (Denmark)

    Arslanagic, Samel; Ziolkowski, W.

    2012-01-01

    The directivities of the fields radiated by a variety of cylindrical and spherical active coated nano-particles, which are excited by their respective sources of illumination at optical frequencies, are investigated. Particular attention is devoted to the influence of the source location and opti......The directivities of the fields radiated by a variety of cylindrical and spherical active coated nano-particles, which are excited by their respective sources of illumination at optical frequencies, are investigated. Particular attention is devoted to the influence of the source location...

  10. Combustion chemical vapor deposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States). School of Materials Science and Engineering

    1995-12-31

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings. In this report, the evaluation of alumina and ceria coatings on a nickel-chromium alloy is described.

  11. Combustion chemical vapor deposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States). School of Materials Science and Engineering

    1995-12-31

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings. In this report, the evaluation of alumina and ceria coatings on a nickel-chromium alloy is described.

  12. Mechanically Invisible Polymer Coatings

    DEFF Research Database (Denmark)

    2014-01-01

    phase comprises particles, said particles comprising a filler material and an encapsulating coating of a second polymeric material, wherein the backbones of the first and second polymeric materials are the same. The composition may be used in electroactive polymers (EAPs) in order to obtain mechanically...... invisible polymer coatings....

  13. Chinese Decorative Coatings Market

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Growth prospects The Chinese market for decorative coatings, excluding non-architectural products such as industrial varnishes,marine paint and other industrially applied coatings, has been growing byaround 10% annually and was estimated to be worth Eurol.3 billion a year, with an annual per capita consumption of just less than 1 liter ofpaint.

  14. Rock-hard coatings

    NARCIS (Netherlands)

    Muller, M.

    2007-01-01

    Aircraft jet engines have to be able to withstand infernal conditions. Extreme heat and bitter cold tax coatings to the limit. Materials expert Dr Ir. Wim Sloof fits atoms together to develop rock-hard coatings. The latest invention in this field is known as ceramic matrix composites. Sloof has sign

  15. Coating of graphene

    NARCIS (Netherlands)

    Schneider, G.F.; Dekker, C.

    2014-01-01

    The present invention is in the field of highly crystalline graphene and coating said graphene with a layer. Said graphene may have further structures, such as nanopores, nanogaps, and nanoribbons. The coated graphene can be used for biomolecular analysis and modification, such as DNA-sequencing, as

  16. Unobtrusive graphene coatings

    NARCIS (Netherlands)

    Mugele, Friedrich Gunther

    2012-01-01

    The contact angle of water drops on substrates for which the wettability is dominated by van der Waals forces remains unchanged when the substrates are coated with a monolayer of graphene. Such 'wetting transparency' could lead to superior conducting and hydrophobic graphene-coated surfaces with tun

  17. Coated electroactive materials

    Energy Technology Data Exchange (ETDEWEB)

    Amine, Khalil; Abouimrane, Ali

    2016-08-30

    A process includes suspending an electroactive material in a solvent, suspending or dissolving a carbon precursor in the solvent; and depositing the carbon precursor on the electroactive material to form a carbon-coated electroactive material. Compositions include a graphene-coated electroactive material prepared from a solution phase mixture or suspension of an electroactive material and graphene, graphene oxide, or a mixture thereof.

  18. Coating of graphene

    NARCIS (Netherlands)

    Schneider, G.F.; Dekker, C.

    2014-01-01

    The present invention is in the field of highly crystalline graphene and coating said graphene with a layer. Said graphene may have further structures, such as nanopores, nanogaps, and nanoribbons. The coated graphene can be used for biomolecular analysis and modification, such as DNA-sequencing, as

  19. Nanostructured Protective Coatings

    Science.gov (United States)

    2006-01-01

    stresses induce strain fatigue with subsequent formation of cracks. Cracking in coatings leads to materials failure observed physically as spallation or...elevated temperatures. In this test a hole is drilled into the substrate before coating it. This allows a fixed amount of air to be trapped at the

  20. The hardness, adhesion, and wear resistance of coatings developed for cobalt-base alloys

    Energy Technology Data Exchange (ETDEWEB)

    Cockeram, B.V.; Wilson, W.L.

    2000-05-01

    One potential approach for reducing the level of nuclear plant radiation exposure that results from activated cobalt wear debris is the use of a wear resistant coating. However, large differences in stiffness between a coating/substrate can result in high interfacial stresses that produce coating de-adhesion when a coated substrate is subjected to high stress wear contact. Scratch adhesion and indentation tests have been used to identify four promising coating processes [1,2]: (1) the use of a thin Cr-nitride coating with a hard and less-stiff interlayer, (2) the use of a thick, multilayered Cr-nitride coating with graded layers, (3) use of the duplex approach, or nitriding to harden the material subsurface followed by application of a multilayered Cr-nitride coating, and (4) application of nitriding alone. The processing, characterization, and adhesion of these coating systems are discussed. The wear resistance and performance has been evaluated using laboratory pin-on-disc, 4-ball, and high stress rolling contact tests. Based on the results of these tests, the best coating candidate from the high-stress rolling contact wear test was the thin duplex coating, which consists of ion nitriding followed deposition of a thin Cr-nitride coating, while the thin Cr-nitride coating exhibited the best results in the 4-ball wear test.

  1. D2 lymphadenectomy alone or with No.14v lymph lode dissection for curable distal gastric cancer with clinical stage t4n+m0:a randomized and multicenter phase iii study in China

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Objective:The study is a prospective, open, randomized multicenter phase III clinical trial with two arms that aims to elucidate superiority of D2 plus No.14v lymph node dissection in comparison with standard D2 surgery in patients with curable distal gastric cancer staged cT4N+M0. hTe primary endpoint is overall survival secondary endpoint is disease-free survival. Each treatment arm includes 255 patients, providing an expected hazard ratio of 0.6.Methods:A prospective, open, randomized multicenter phase III clinical trial was designed to elucidate superiority of D2 plus No.14v lymph node dissection in improving overall survival with regard to standard D2 surgery in patients with curable distal gastric cancer staged cT4N+M0. hTe study is a multi-institutional prospective randomized controlled trial, with participating institutions including 20 specialized centers. Treatment methodsEnrolled patients are randomized to 14v- (arm A) or to 14v + (arm B).Results:End points the primary endpoint is overall survival secondary endpoint is disease-free survival.Conclusion:Results are unifnished.

  2. Radiation Therapy: Professions in Radiation Therapy

    Science.gov (United States)

    ... Resources Professions Site Index A-Z Professions in Radiation Therapy Radiation Oncologist Therapeutic Medical Physicist Radiation Therapist Dosimetrist Radiation Oncology Nurse Social Worker Dietitian Radiation Oncologist Radiation oncologists are physicians who oversee the ...

  3. Development of wear-resistant coatings for cobalt-base alloys

    Energy Technology Data Exchange (ETDEWEB)

    Cockeram, B.V.

    1999-10-22

    The level of nuclear plant radiation exposure due to activated cobalt wear debris could potentially be reduced by covering the cobalt-base materials with a wear resistant coating. Laboratory pin-on-disc and rolling contact wear tests were used to evaluate the wear performance of several coatings. Based on the results of these tests, multilayer Cr-nitride coatings and ion nitriding are the most promising approaches.

  4. The radiation crosslinking process and new products

    Science.gov (United States)

    Ueno, Keiji

    In 1988 there were over 90 EB accelerators for industrial use in Japan. The number one industrial application was Wire and Cable, the 2nd was PE foam and Curing, and the 3rd was Precure of tyre. R & D has a very high ration of EB accelerator use. Low energy industrial applications were coated steel (white board), plaster slab, coated paper, magnetic tape and floppy disks. As a new application of the radiation crosslinking process, we have studied radiation crosslinking of engineering plastics and succeeded in improving the hea tresistivity without using glass fibers. Many kinds of polyfunctional monomers used as crosslinking reagents of irradiated Nylon and PBT were studied.

  5. Optical studies of multilayer dielectric-metal-dielectric coatings as applied to solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Demichelis, F.; Minetti-Mezzetti, E.; Perotto, V.

    1982-09-01

    A study of antireflection coatings for solar cells which provide maximum transmittance in the range of the spectral response of the cell and maximum reflectance in the IR portion of the spectrum of normally incident radiation is reported. Dielectric-metal-dielectric filters with a relatively low number of dielectric layers are designed as coatings for silicon and GaAs solar cells.

  6. Flexible fiber-reinforced composites with improved interfacial adhesion by mussel-inspired polydopamine and poly(methyl methacrylate) coating.

    Science.gov (United States)

    Yi, Mi; Sun, Hongyang; Zhang, Hongcheng; Deng, Xuliang; Cai, Qing; Yang, Xiaoping

    2016-01-01

    To obtain a kind of light-curable fiber-reinforced composite for dental restoration, an excellent interfacial adhesion between the fiber and the acrylate resin matrix is quite essential. Herein, surface modification on glass fibers were carried out by coating them with poly(methyl methacrylate) (PMMA), polydopamine (PDA), or both. The PMMA or PDA coating was performed by soaking fibers in PMMA/acetone solution or dopamine aqueous solution. PDA/PMMA co-coated glass fibers were obtained by further soaking PDA-coated fibers in PMMA/acetone solution. These modified fibers were impregnated with bisphenol A glycidyl methacrylate (Bis-GMA)/triethylene glycol dimethacrylate (TEGDMA) (5:5, w/w) dental resin at a volume fraction of 75%, using unmodified fibers as reference. Light-cured specimens were submitted to evaluations including flexural properties, morphological observation, dynamic mechanical thermal analysis (DMTA) and pull-out test. In comparison with unmodified glass fibers, all the modified glass fibers showed enhancements in flexural strength and modulus of Bis-GMA/TEGDMA resin composites. Results of DMTA and pull-out tests confirmed that surface modification had significantly improved the interfacial adhesion between the glass fiber and the resin matrix. Particularly, the PDA/PMMA co-coated glass fibers displayed the most efficient reinforcement and the strongest interfacial adhesion due to the synergetic effects of PDA and PMMA. It indicated that co-coating method was a promising approach in modifying the interfacial compatibility between inorganic glass fiber and organic resin matrix. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. A simple circular-polarized antenna: Circular waveguide horn coated with lossy magnetic material

    Science.gov (United States)

    Lee, Choon S.; Justice, D. W.; Lee, Shung-Wu

    1988-01-01

    It is shown that a circular waveguide horn coated with a lossy material in its interior wall can be used as an alternative to a corrugated waveguide for radiating a circularly polarized (CP) field. To achieve good CP radiation, the diameter of the structure must be larger than the free-space wavelength, and the coating material must be sufficiently lossy and magnetic. The device is cheaper and lighter in weight than the corrugated one.

  8. Neutron irradiation and high temperature effects on amorphous Fe-based nano-coatings on steel - A macroscopic assessment

    Science.gov (United States)

    Simos, N.; Zhong, Z.; Dooryhee, E.; Ghose, S.; Gill, S.; Camino, F.; Şavklıyıldız, İ.; Akdoğan, E. K.

    2017-06-01

    The study revealed that loss of ductility in an amorphous Fe-alloy coating on a steel substrate composite structure was essentially prevented from occurring, following radiation with modest neutron doses of ∼2 × 1018 n/cm2. At the higher neutron dose of ∼2 × 1019, macroscopic stress-strain analysis showed that the amorphous Fe-alloy nanostructured coating, while still amorphous, experienced radiation-induced embrittlement, no longer offering protection against ductility loss in the coating-substrate composite structure. Neutron irradiation in a corrosive environment revealed exemplary oxidation/corrosion resistance of the amorphous Fe-alloy coating, which is attributed to the formation of the Fe2B phase in the coating. To establish the impact of elevated temperatures on the amorphous-to-crystalline transition in the amorphous Fe-alloy, electron microscopy was carried out which confirmed the radiation-induced suppression of crystallization in the amorphous Fe-alloy nanostructured coating.

  9. Therma1 Conductivity and Durability of Advanced Thermal Barrier Coatings

    Science.gov (United States)

    Zhu, Dong-Ming; Miller, Robert A.

    2003-01-01

    Thermal barrier coatings (TBCs) will play a crucial role in advanced gas turbine engines because of their ability to further increase engine operating temperature and reduce cooling, thus helping to achieve engine emission and efficiency goals. Future TBCs must be designed with increased phase stability, lower thermal conductivity, and improved sintering and thermal stress resistance in order to effectively protect engine hot-section components. Advanced low conductivity TBCs are being developed at NASA by incorporating multi-component oxide dopants into zirconia-yttria or hafnia-yttria to promote the formation of thermodynamically stable defect clusters within the coating structures. This presentation will primarily focus on thermal conductivity and durability of the novel defect cluster thermal barrier coatings for turbine airfoil and combustor applications, determined by a unique CO2 laser heat-flux approach. The laser heat-flux testing approach emphasizes the real-time monitoring and assessment of the coating thermal conductivity under simulated engine temperature and thermal gradient conditions. The conductivity increase due to coating sintering (and/or phase change) and the conductivity decrease due to coating delamination have been determined under steady-state, cyclic, uniform or non-uniform heat-flux conditions. The coating radiation flux resistance has been evaluated by varying coating thermal gradients, and also by using a laser-heated radiative-flux source. Advanced multi-component TBC systems have been shown to have significantly reduced thermal conductivity and improved high temperature stability due to the nano-sized, low mobility defect clusters associated with the paired rare earth dopant additions. The effect of oxide defect cluster dopants on coating thermal conductivity, thermal stability and furnace cyclic durability will also be discussed. The current low conductivity TBC systems have demonstrated long-term cyclic durability at very high

  10. Fluorine Based Superhydrophobic Coatings

    Directory of Open Access Journals (Sweden)

    Jean-Denis Brassard

    2012-05-01

    Full Text Available Superhydrophobic coatings, inspired by nature, are an emerging technology. These water repellent coatings can be used as solutions for corrosion, biofouling and even water and air drag reduction applications. In this work, synthesis of monodispersive silica nanoparticles of ~120 nm diameter has been realized via Stöber process and further functionalized using fluoroalkylsilane (FAS-17 molecules to incorporate the fluorinated groups with the silica nanoparticles in an ethanolic solution. The synthesized fluorinated silica nanoparticles have been spin coated on flat aluminum alloy, silicon and glass substrates. Functionalization of silica nanoparticles with fluorinated groups has been confirmed by Fourier Transform Infrared spectroscopy (FTIR by showing the presence of C-F and Si-O-Si bonds. The water contact angles and surface roughness increase with the number of spin-coated thin films layers. The critical size of ~119 nm renders aluminum surface superhydrophobic with three layers of coating using as-prepared nanoparticle suspended solution. On the other hand, seven layers are required for a 50 vol.% diluted solution to achieve superhydrophobicity. In both the cases, water contact angles were more than 150°, contact angle hysteresis was less than 2° having a critical roughness value of ~0.700 µm. The fluorinated silica nanoparticle coated surfaces are also transparent and can be used as paint additives to obtain transparent coatings.

  11. Phenol-formaldehyde intumescent coating composition and coating prepared therefrom

    Science.gov (United States)

    Salyer, Ival O. (Inventor); Fox, Bernard L. (Inventor)

    1986-01-01

    Intumescent coatings which form a thick, uniform, fine celled, low density foam upon exposure to a high intensity heat flux or flame are disclosed, the invention coatings comprise phenolic resin prepolymer containing a blowing agent and a nucleating agent; in the preferred embodiments the coatings also contains a silicone surfactant, the coatings are useful in thermal and fire protection systems.

  12. Leucemia linfóide aguda: uma doença curável Acute lymphoblastic leukemia: a curable disease

    Directory of Open Access Journals (Sweden)

    Francisco Pedrosa

    2002-04-01

    75.000 new ALL cases annually diagnosed throughout the world, around 60.000 (80% have no access to the new treatments and are excluded from the cure process. The challenge of making ALL a curable disease is being met with the report of survival rates over 50% for children treated in countries with limited resources. In El Salvador, Bonilla has achieved increasing the survival rates in children with ALL from 5% to 50%. In Recife, Pedrosa accomplished bringing the 29% cure rate in the 80’s to the 75% current cure rate.

  13. Coatings to prevent frost

    DEFF Research Database (Denmark)

    Lusada, Ricardo; Holberg, Stefan; Bennedsen, Jeanette Marianne Dalgaard

    2016-01-01

    The ability of hydrophobic, organic–inorganic hybrid coatings to decelerate frost propagation was investigated. Compared to a bare aluminum surface, the coatings do not significantly reduce the freezing probability of supercooled water drops. On both surfaces, the probability for ice nucleation...... at temperatures just below 0°C, for example at −4°C, is low. Freezing of a single drop on aluminum leads, however, to instant freezing of the complete surface. On hydrophobic coatings, such a freezing drop is isolated; the frozen area grows slowly. At −4°C surface temperature in a +12°C/90% relative humidity...

  14. 环保节能型水性聚氨酯建筑涂料研究进展%Progress of environmentally friendly and energy-saving waterborne polyurethane architectural coatings

    Institute of Scientific and Technical Information of China (English)

    张凡; 杨建军; 吴庆云; 张建安; 吴明元

    2014-01-01

    Using water as the dispersion medium, the waterborne polyurethane coating is environmentally friendly compared to the solvent-based polyurethane coating in terms of reducing VOC emissions greatly. This article has reviewed research progress in waterborne polyurethane coating to achieve the energy-saving and environment-friendly buildings over the last decade. There are four aspects as the focus of this review:the thermal insulation coating based on waterborne polyurethane, the phase change thermal storage materials with polyurethane shell, the UV curable waterborne polyurethane coating and the improvment of water resistence and bacterium resistance of waterborne polyurethane coating.%综述了近几年来环保型、节能型水性聚氨酯涂料的研发和应用情况。主要包括:水性聚氨酯(WPU)保温隔热涂料,以聚氨酯为壳层材料的相变储能材料,UV固化WPU工艺,提高水性聚氨酯涂料的耐水性和防霉抗菌性等。

  15. Advanced thermal barrier coating systems

    Science.gov (United States)

    Dorfman, M. R.; Reardon, J. D.

    1985-01-01

    Current state-of-the-art thermal barrier coating (TBC) systems consist of partially stabilized zirconia coatings plasma sprayed over a MCrAlY bond coat. Although these systems have excellent thermal shock properties, they have shown themselves to be deficient for a number of diesel and aircraft applications. Two ternary ceramic plasma coatings are discussed with respect to their possible use in TBC systems. Zirconia-ceria-yttria (ZCY) coatings were developed with low thermal conductivities, good thermal shock resistance and improved resistance to vanadium containing environments, when compared to the baseline yttria stabilized zirconia (YSZ) coatings. In addition, dense zirconia-titania-yttria (ZTY) coatings were developed with particle erosion resistance exceeding conventional stabilized zirconia coatings. Both coatings were evaluated in conjunction with a NiCr-Al-Co-Y2O3 bond coat. Also, multilayer or hybrid coatings consisting of the bond coat with subsequent coatings of zirconia-ceria-yttria and zirconia-titania-yttria were evaluated. These coatings combine the enhanced performance characteristics of ZCY with the improved erosion resistance of ZTY coatings. Improvement in the erosion resistance of the TBC system should result in a more consistent delta T gradient during service. Economically, this may also translate into increased component life simply because the coating lasts longer.

  16. Pelvic radiation - discharge

    Science.gov (United States)

    Radiation of the pelvis - discharge; Cancer treatment - pelvic radiation; Prostate cancer - pelvic radiation; Ovarian cancer - pelvic radiation; Cervical cancer - pelvic radiation; Uterine cancer - pelvic radiation; Rectal cancer - pelvic radiation

  17. Development of wear-resistant coatings for cobalt-base alloys

    Energy Technology Data Exchange (ETDEWEB)

    Cockeram, B.V.

    1999-03-01

    The costs and hazards resulting from nuclear plant radiation exposure with activated cobalt wear debris could potentially be reduced by covering the cobalt-base materials with a wear resistant coating. However, the hardnesses of many cobalt-base wear alloys are significantly lower than conventional PVD hard coatings, and mechanical support of the hard coating is a concern. Four approaches have been taken to minimize the hardness differences between the substrate and PVD hard coating: (1) use a thin Cr-nitride hard coating with layers that are graded with respect to hardness, (2) use a thicker, multilayered coating (Cr-nitride or Zr-nitride) with graded layers, (3) use nitriding to harden the alloy subsurface followed by application of a multilayered coating of Cr-nitride, and (4) use of nitriding alone. Since little work has been done on application of PVD hard coatings to cobalt-base alloys, some details on process development and characterization of the coatings is presented. Scratch testing was used to evaluate the adhesion of the different coatings. A bench-top rolling contact test was used to evaluate the wear resistance of the coatings. The test results are discussed, and the more desirable coating approaches are identified.

  18. Evidence that we need more radiation for good health

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In 1958 the speaker believed that background radiation might cause a fatal cancer. In 1970 he believed there was no risk from background or from the small doses received from diagnostic uses of X-rays. Since 1990 he has come to believe that for good health most people need more radiation than they receive from nature. The talk will emphasize the results of two large British radiologists who entered the field between 1955 and 1979, when compared to all other male English physicians of the same age. Had a 29% lower cancer death rate, a 36% lower death rate from non-cancer and a 32% lower death rate from all causes. The chances of such a health improvement being accidental is less than one in one thousand. The lower death rate from all causes results in more than a three year increase in longevity-the same increase in longevity that would result ff all cancer were curable. The US Government sponsored nuclear shipyard worker study shows that the 28,000 nuclear shipyard workers with the greatest radiation doses, when compared to 32,500 shipyard workers who had no on-the-job radiation, had significantly less cancer and a 24% lower death rate from all causes. That is, the nuclear workers had nearly a three-year increase in longevity.The chance of that health improvement being accidental is less than one in ten million billion. The talk will describe a double blind study to test the hypothesis that a moderate dose of ionizing radiation stimulates the immune system of senior citizens in the I.S. Gulf States where cancer mortality is 25% greater than in the mountains, which have about 300% more background radiation than the Gulf States. Radiation deficiency may be a health problem in many areas of the world.

  19. Coated semiconductor devices for neutron detection

    Energy Technology Data Exchange (ETDEWEB)

    Klann, Raymond T. (Bolingbrook, IL); McGregor, Douglas S. (Whitmore Lake, MI)

    2002-01-01

    A device for detecting neutrons includes a semi-insulated bulk semiconductor substrate having opposed polished surfaces. A blocking Schottky contact comprised of a series of metals such as Ti, Pt, Au, Ge, Pd, and Ni is formed on a first polished surface of the semiconductor substrate, while a low resistivity ("ohmic") contact comprised of metals such as Au, Ge, and Ni is formed on a second, opposed polished surface of the substrate. In one embodiment, n-type low resistivity pinout contacts comprised of an Au/Ge based eutectic alloy or multi-layered Pd/Ge/Ti/Au are also formed on the opposed polished surfaces and in contact with the Schottky and ohmic contacts. Disposed on the Schottky contact is a neutron reactive film, or coating, for detecting neutrons. The coating is comprised of a hydrogen rich polymer, such as a polyolefin or paraffin; lithium or lithium fluoride; or a heavy metal fissionable material. By varying the coating thickness and electrical settings, neutrons at specific energies can be detected. The coated neutron detector is capable of performing real-time neutron radiography in high gamma fields, digital fast neutron radiography, fissile material identification, and basic neutron detection particularly in high radiation fields.

  20. Effect of polymer coating on leakage losses in Bragg fibers.

    Science.gov (United States)

    Uspenskii, Yu A; Uzorin, E E; Vinogradov, A V; Likhachev, M E; Semjonov, S L; Bubnov, M M; Dianov, E M; Jamier, R; Février, S

    2007-05-15

    It is found that the reflection of leaky radiation from the interface between the outer silica cladding and the coating polymer greatly modifies the loss spectrum of Bragg fibers. A simple model that describes this effect is proposed and confirmed by measurement and computation.

  1. Defect Detection in Composite Coatings by Computational Simulation Aided Thermography

    Science.gov (United States)

    Almeida, R. M.; Souza, M. P. V.; Rebello, J. M. A.

    2010-02-01

    Thermography is based on the measurement of superficial temperature distribution of an object inspected subjected to tension, normally thermal heat. This measurement is performed with a thermographic camera that detects the infrared radiation emitted by every object. In this work thermograph was simulated by COMSOL software for optimize experimental parameters in composite material coatings inspection.

  2. History force on coated microbubbles propelled by ultrasound

    NARCIS (Netherlands)

    Garbin, Valeria; Dollet, Benjamin; Overvelde, Marlies; Cojoc, Dan; Di Fabrizio, Enzo; Wijngaarden, van Leen; Prosperetti, Andrea; Jong, de Nico; Lohse, Detlef; Versluis, Michel

    2009-01-01

    In this paper the unsteady translation of coated microbubbles propelled by acoustic radiation force is studied experimentally. A system of two pulsating microbubbles of the type used as contrast agent in ultrasound medical imaging is considered, which attract each other as a result of the secondary

  3. Aluminum phosphate coatings

    Science.gov (United States)

    Sambasivan, Sankar; Steiner, Kimberly A.; Rangan, Krishnaswamy K.

    2007-12-25

    Aluminophosphate compounds and compositions as can be used for substrate or composite films and coating to provide or enhance, without limitation, planarization, anti-biofouling and/or anti-microbial properties.

  4. Inorganic Coatings Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The inorganic Coatings Lab provides expertise to Navy and Joint Service platforms acquisition IPTs to aid in materials and processing choices which balance up-front...

  5. Friction surfaced Stellite6 coatings

    Energy Technology Data Exchange (ETDEWEB)

    Rao, K. Prasad; Damodaram, R. [Department of Metallurgical and Materials Engineering - Indian Institute of Technology Madras, Chennai 600 036 (India); Rafi, H. Khalid, E-mail: khalidrafi@gmail.com [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600 036 (India); Ram, G.D. Janaki [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600 036 (India); Reddy, G. Madhusudhan [Metal Joining Group, Defence Metallurgical Research Laboratory (DMRL) Kanchanbagh, Hyderabad 500 058 (India); Nagalakshmi, R. [Welding Research Institute, Bharat Heavy Electricals Limited, Tiruchirappalli 620 014 (India)

    2012-08-15

    Solid state Stellite6 coatings were deposited on steel substrate by friction surfacing and compared with Stellite6 cast rod and coatings deposited by gas tungsten arc and plasma transferred arc welding processes. Friction surfaced coatings exhibited finer and uniformly distributed carbides and were characterized by the absence of solidification structure and compositional homogeneity compared to cast rod, gas tungsten arc and plasma transferred coatings. Friction surfaced coating showed relatively higher hardness. X-ray diffraction of samples showed only face centered cubic Co peaks while cold worked coating showed hexagonally close packed Co also. - Highlights: Black-Right-Pointing-Pointer Stellite6 used as coating material for friction surfacing. Black-Right-Pointing-Pointer Friction surfaced (FS) coatings compared with casting, GTA and PTA processes. Black-Right-Pointing-Pointer Finer and uniformly distributed carbides in friction surfaced coatings. Black-Right-Pointing-Pointer Absence of melting results compositional homogeneity in FS Stellite6 coatings.

  6. Enhanced biocompatibility and osseointegration of calcium titanate coating on titanium screws in rabbit femur.

    Science.gov (United States)

    Wang, Zi-Li; He, Rong-Zhen; Tu, Bin; Cao, Xu; He, Jin-Shen; Xia, Han-Song; Liang, Chi; Zou, Min; Wu, Song; Wu, Zhen-Jun; Xiong, Kun

    2017-06-01

    This study aimed to examine the biocompatibility of calcium titanate (CaTiO3) coating prepared by a simplified technique in an attempt to assess the potential of CaTiO3 coating as an alternative to current implant coating materials. CaTiO3-coated titanium screws were implanted with hydroxyapatite (HA)-coated or uncoated titanium screws into medial and lateral femoral condyles of 48 New Zealand white rabbits. Imaging, histomorphometric and biomechanical analyses were employed to evaluate the osseointegration and biocompatibility 12 weeks after the implantation. Histology and scanning electron microscopy revealed that bone tissues surrounding the screws coated with CaTiO3 were fully regenerated and they were also well integrated with the screws. An interfacial fibrous membrane layer, which was found in the HA coating group, was not noticeable between the bone tissues and CaTiO3-coated screws. X-ray imaging analysis showed in the CaTiO3 coating group, there was a dense and tight binding between implants and the bone tissues; no radiation translucent zone was found surrounding the implants as well as no detachment of the coating and femoral condyle fracture. In contrast, uncoated screws exhibited a fibrous membrane layer, as evidenced by the detection of a radiation translucent zone between the implants and the bone tissues. Additionally, biomechanical testing revealed that the binding strength of CaTiO3 coating with bone tissues was significantly higher than that of uncoated titanium screws, and was comparable to that of HA coating. The study demonstrated that CaTiO3 coating in situ to titanium screws possesses great biocompatibility and osseointegration comparable to HA coating.

  7. Nanostructured Superhydrophobic Coatings

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-03-01

    This factsheet describes a research project that deals with the nanostructured superhydrophobic (SH) powders developed at ORNL. This project seeks to (1) improve powder quality; (2) identify binders for plastics, fiberglass, metal (steel being the first priority), wood, and other products such as rubber and shingles; (3) test the coated product for coating quality and durability under operating conditions; and (4) application testing and production of powders in quantity.

  8. Spin coating apparatus

    Science.gov (United States)

    Torczynski, John R.

    2000-01-01

    A spin coating apparatus requires less cleanroom air flow than prior spin coating apparatus to minimize cleanroom contamination. A shaped exhaust duct from the spin coater maintains process quality while requiring reduced cleanroom air flow. The exhaust duct can decrease in cross section as it extends from the wafer, minimizing eddy formation. The exhaust duct can conform to entrainment streamlines to minimize eddy formation and reduce interprocess contamination at minimal cleanroom air flow rates.

  9. Coated 4340 Steel

    Science.gov (United States)

    2013-08-26

    alternative coatings qualified to MIL-PRE-23377 Class N and an electroplated zinc - nickel alloy passivated with a trivalent chromium solution which is...effect of a non-chromate primer and zinc - nickel plating with non-chromate passivation as alternatives to the chromate primer and cadmium plating with...NAWCADPAX/TR-2013/252 COATED 4340 STEEL by E. U. Lee C. Lei M. Stanley B. Pregger C. Matzdorf 26 August 2013

  10. Hydroxyapatite coatings for biomedical applications

    CERN Document Server

    Zhang, Sam

    2013-01-01

    Hydroxyapatite coatings are of great importance in the biological and biomedical coatings fields, especially in the current era of nanotechnology and bioapplications. With a bonelike structure that promotes osseointegration, hydroxyapatite coating can be applied to otherwise bioinactive implants to make their surface bioactive, thus achieving faster healing and recovery. In addition to applications in orthopedic and dental implants, this coating can also be used in drug delivery. Hydroxyapatite Coatings for Biomedical Applications explores developments in the processing and property characteri

  11. Residual stresses within sprayed coatings

    Institute of Scientific and Technical Information of China (English)

    JIANG Yi; XU Bin-shi; WANG Hai-dou

    2005-01-01

    Some important developments of residual stress researches for coating-based systems were studied. The following topics were included the sources of residual stresses in coatings: error analysis of Stoney's equation in the curvature method used for the measurement of coating residual stress, the modeling of residual stress and some analytical models for predicting the residual stresses in coatings. These topics should provide some important insights for the fail-safe design of the coating-based systems.

  12. Biocompatibility of Niobium Coatings

    Directory of Open Access Journals (Sweden)

    René Olivares-Navarrete

    2011-09-01

    Full Text Available Niobium coatings deposited by magnetron sputtering were evaluated as a possible surface modification for stainless steel (SS substrates in biomedical implants. The Nb coatings were deposited on 15 mm diameter stainless steel substrates having an average surface roughness of 2 mm. To evaluate the biocompatibility of the coatings three different in vitro tests, using human alveolar bone derived cells, were performed: cellular adhesion, proliferation and viability. Stainless steel substrates and tissue culture plastic were also studied, in order to give comparative information. No toxic response was observed for any of the surfaces, indicating that the Nb coatings act as a biocompatible, bioinert material. Cell morphology was also studied by immune-fluorescence and the results confirmed the healthy state of the cells on the Nb surface. X-ray diffraction analysis of the coating shows that the film is polycrystalline with a body centered cubic structure. The surface composition and corrosion resistance of both the substrate and the Nb coating were also studied by X-ray photoelectron spectroscopy and potentiodynamic tests. Water contact angle measurements showed that the Nb surface is more hydrophobic than the SS substrate.

  13. Thermal implications of interactions between insulation, solar reflectance, and fur structure in the summer coats of diverse species of kangaroo.

    Science.gov (United States)

    Dawson, Terence J; Maloney, Shane K

    2017-04-01

    Not all of the solar radiation that impinges on a mammalian coat is absorbed and converted into thermal energy at the coat surface. Some is reflected back to the environment, while another portion is reflected further into the coat where it is absorbed and manifested as heat at differing levels. Substantial insulation in a coat limits the thermal impact at the skin of solar radiation, irrespective where in the coat it is absorbed. In coats with low insulation, the zone where solar radiation is absorbed may govern the consequent heat load on the skin (HL-SR). Thin summer furs of four species of kangaroo from differing climatic zones were used to determine how variation in insulation and in coat spectral and structural characteristics influence the HL-SR. Coat depth, structure, and solar reflectance varied between body regions, as well as between species. The modulation of solar radiation and resultant heat flows in these coats were measured at low (1 m s(-1)) and high (6 m s(-1)) wind speeds by mounting them on a heat flux transducer/temperature-controlled plate apparatus in a wind tunnel. A lamp with a spectrum similar to solar radiation was used as a proxy for the sun. We established that coat insulation was largely determined by coat depth at natural fur lie, despite large variations in fibre density, fibre diameter, and fur mass. Higher wind speed decreased coat insulation, but depth still determined the overall level. A multiple regression analysis that included coat depth (insulation), fibre diameter, fibre density, and solar reflectance was used to determine the best predictors of HL-SR. Only depth and reflectance had significant impacts and both factors had negative weights, so, as either insulation or reflectance increased, HL-SR declined, the larger impact coming from coat reflectance. This reverses the pattern observed in deep coats where insulation dominates over effects of reflectance. Across all coats, as insulation declined, reflectance increased

  14. Atoms, Radiation, and Radiation Protection

    CERN Document Server

    Turner, James E

    2007-01-01

    Atoms, Radiation, and Radiation Protection offers professionals and advanced students a comprehensive coverage of the major concepts that underlie the origins and transport of ionizing radiation in matter. Understanding atomic structure and the physical mechanisms of radiation interactions is the foundation on which much of the current practice of radiological health protection is based. The work covers the detection and measurement of radiation and the statistical interpretation of the data. The procedures that are used to protect man and the environment from the potential harmful effects of

  15. Advanced Environmental Barrier Coatings Development for Si-Based Ceramics

    Science.gov (United States)

    Zhu, Dong-Ming; Choi, R. Sung; Robinson, Raymond C.; Lee, Kang N.; Bhatt, Ramakrishna T.; Miller, Robert A.

    2005-01-01

    Advanced environmental barrier coating concepts based on multi-component HfO2 (ZrO2) and modified mullite systems are developed for monolithic Si3N4 and SiC/SiC ceramic matrix composite (CMC) applications. Comprehensive testing approaches were established using the water vapor cyclic furnace, high pressure burner rig and laser heat flux steam rig to evaluate the coating water vapor stability, cyclic durability, radiation and erosion resistance under simulated engine environments. Test results demonstrated the feasibility and durability of the environmental barrier coating systems for 2700 to 3000 F monolithic Si3N4 and SiC/SiC CMC component applications. The high-temperature-capable environmental barrier coating systems are being further developed and optimized in collaboration with engine companies for advanced turbine engine applications.

  16. Optical Property Evaluation of Next Generation Thermal Control Coatings

    Science.gov (United States)

    Jaworske, Donald A.; Deshpande, Mukund S.; Pierson, Edward A.

    2010-01-01

    Next generation white thermal control coatings were developed via the Small Business Innovative Research program utilizing lithium silicate chemistry as a binder. Doping of the binder with additives yielded a powder that was plasma spray capable and that could be applied to light weight polymers and carbon-carbon composite surfaces. The plasma sprayed coating had acceptable beginning-of-life and end-of-live optical properties, as indicated by a successful 1.5 year exposure to the space environment in low Earth orbit. Recent studies also showed the coating to be durable to simulated space environments consisting of 1 keV and 10 keV electrons, 4.5 MeV electrons, and thermal cycling. Large scale deposition was demonstrated on a polymer matrix composite radiator panel, leading to the selection of the coating for use on the Gravity Recovery And Interior Laboratory (GRAIL) mission.

  17. Development of NEG Coating for RHIC Experimental Beamtubes

    CERN Document Server

    Weiss, Daniel; Hseuh Hsiao Chaun; Todd, Robert J

    2005-01-01

    As RHIC beam intensity increases beyond original scope, pressure rises in some regions have been observed. The luminosity limiting pressure rises are associated with electron multi-pacting, electron stimulated desorption and beam induced desorption. Non-Evaporable Getter (NEG) coated beampipes have been proven effective to suppress pressure rise in synchrotron radiation facilities. Standard beampipes have been NEG coated by a vendor and added to many RHIC UHV regions. BNL is developing a cylindrical magnetron sputtering system to NEG coat special beryllium beampipes installed in RHIC experimental regions. It features a hollow, liquid cooled cathode producing power density of 500W/m and deposition rate of 5000 Angstrom/hr on 7.5cm OD beampipe. The cathode, a titanium tube partially covered with zirconium and vanadium ribbons, is oriented for horizontal coating of 4m long chambers. Ribbons and magnets are arranged to provide uniform sputtering distribution and deposited NEG composition. Vacuum performance of NE...

  18. Radiation Chemistry

    Science.gov (United States)

    Wojnárovits, L.

    Ionizing radiation causes chemical changes in the molecules of the interacting medium. The initial molecules change to new molecules, resulting in changes of the physical, chemical, and eventually biological properties of the material. For instance, water decomposes to its elements H2 and O2. In polymers, degradation and crosslinking take place. In biopolymers, e.g., DNS strand breaks and other alterations occur. Such changes are to be avoided in some cases (radiation protection), however, in other cases they are used for technological purposes (radiation processing). This chapter introduces radiation chemistry by discussing the sources of ionizing radiation (radionuclide sources, machine sources), absorption of radiation energy, techniques used in radiation chemistry research, and methods of absorbed energy (absorbed dose) measurements. Radiation chemistry of different classes of inorganic (water and aqueous solutions, inorganic solids, ionic liquids (ILs)) and organic substances (hydrocarbons, halogenated compounds, polymers, and biomolecules) is discussed in concise form together with theoretical and experimental backgrounds. An essential part of the chapter is the introduction of radiation processing technologies in the fields of polymer chemistry, food processing, and sterilization. The application of radiation chemistry to nuclear technology and to protection of environment (flue gas treatment, wastewater treatment) is also discussed.

  19. 紫外光固化亚光涂料的配方设计和助剂筛选%Research on Formula Design and Additive Selection of UV Curable Matte Coating

    Institute of Scientific and Technical Information of China (English)

    范雷平

    2015-01-01

    紫外光(UV)固化涂料在应用中存在消光难、消光粉定向差、光泽不稳定以及容易发花等问题.为了解决这些问题,本研究就紫外光固化亚光涂料中消光粉、蜡粉以及各种涂料助剂对涂膜光泽的影响进行了分析和测试,最终通过选择合适的助剂以及消光剂来改善紫外光固化涂料的光泽稳定性、透明性和消光剂的定向排列性.为紫外光固化亚光涂料的配方设计和助剂筛选提出了较为清晰的解决思路.

  20. Optical deterioration of coated wrapping paper

    Directory of Open Access Journals (Sweden)

    Katarina Itrić

    2015-05-01

    Full Text Available The aim of the research was to analyse the dependence of storage conditions on the optical deterioration of coated wrapping paper. Three methods of common storage conditions were applied for a period of three years: preservation in the dark and dry place, storage in the common office conditions, and keeping in room conditions that enabled stronger influence of natural light and atmosphere pollutants. In order to examine optical modifications due to accelerated ageing, the same sample of paper was exposed to UV/VIS lamp radiation. Visible and IR spectroscopy were used for the characterization and comparison of paper degradation with the emphasis on the colour alterations as the crucial quality component. This research provides a solid basis for further development of non-invasive methods for investigating and predicting shelf life of coated wrapping paper.

  1. Controlled Thermal Expansion Coat for Thermal Barrier Coatings

    Science.gov (United States)

    Brindley, William J. (Inventor); Miller, Robert A. (Inventor); Aikin, Beverly J. M. (Inventor)

    1999-01-01

    A improved thermal barrier coating and method for producing and applying such is disclosed herein. The thermal barrier coating includes a high temperature substrate, a first bond coat layer applied to the substrate of MCrAlX, and a second bond coat layer of MCrAlX with particles of a particulate dispersed throughout the MCrAlX and the preferred particulate is Al2O3. The particles of the particulate dispersed throughout the second bond coat layer preferably have a diameter of less then the height of the peaks of the second bond coat layer, or a diameter of less than 5 microns. The method of producing the second bond coat layer may either include the steps of mechanical alloying of particles throughout the second bond coat layer, attrition milling the particles of the particulate throughout the second bond coat layer, or using electrophoresis to disperse the particles throughout the second bond coat layer. In the preferred embodiment of the invention, the first bond coat layer is applied to the substrate, and then the second bond coat layer is thermally sprayed onto the first bond coat layer. Further, in a preferred embodiment of die invention, a ceramic insulating layer covers the second bond coat layer.

  2. Development of Fire-Retardant Elastic Acrylic Finishing Coating%阻燃型弹性丙烯酸饰面涂料的研制

    Institute of Scientific and Technical Information of China (English)

    陈铁鑫; 郭岳峰

    2012-01-01

    The fire - retardant elastic acrylic finishing coating applied on polyurethane foam was prepared with UV curable elastomeric acrylic emulsion as binder and modified ammonium polyphosphate ( APP) as fire retardant. Orthogonal test was used to optimize the coating formulation,the best content of fire retardant was 35%. Effection of UV and sun lights on coating tensile property were studied,and found that exoposure to UV 4 h and sun light 7 d,the tensile strength reached the highest; coating fire - retardant property was ev-alated by use of oxygen index and mass loss.%采用紫外光固化的弹性丙烯酸树脂为基料,改性聚磷酸铵为阻燃剂,制备了聚氨酯泡沫用阻燃型弹性丙烯酸饰面涂料,通过正交试验对涂料配方进行了优化,确定了阻燃剂最佳含量为35%.考察了紫外光和太阳光对涂层拉伸强度的影响,紫外光4h,太阳光7d,涂层拉伸性能达到最佳;采用氧指数及质量损失评估了涂层的阻燃性能.

  3. High performance fluoride optical coatings for DUV optics

    Science.gov (United States)

    Zhang, Lichao; Cai, Xikun

    2014-08-01

    In deep ultraviolet region that typical applications are used on the ArF wavelength, coated optics should meet stringent requirements of optical systems. To meet these requirements, systematical researches are carried out on fabrication and characterization methods of fluoride coatings. First, by optimizing of deposition processes, dense coatings with the refractive index of ~1.7 for LaF3 and ~1.4 for MgF2, together with extinction coefficients of ~2×10-4 on 193nm were realized. The transmission of AR coating for 193nm achieved by using optimized deposition techniques is 99.8%. Second, a method of designing shadowing masks was developed to solve the problem of correcting coating thickness distributions for complex DUV systems. By using the method, the thickness distribution error specification of 3% PV has been achieved on substrates with ~300mm diameters and large curvatures. Finally, the laser calorimetry method is used to evaluate the laser radiation stability of fluoride coatings. It is turned out that the damage coefficients of fluoride coatings, which are defined as the values of unrecoverable increase of the absorption during the laser irradiation process, are much lower than that of fused silica substrates. The above progresses could further support the realization of high performance DUV optical systems.

  4. Radiation carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Fry, R.J.M.

    1976-01-01

    The risk of iatrogenic tumors with radiation therapy is so outweighed by the benefit of cure that estimates of risk have not been considered necessary. However, with the introduction of chemotherapy, combined therapy, and particle radiation therapy, the comparative risks should be examined. In the case of radiation, total dose, fractionation, dose rate, dose distribution, and radiation quality should be considered in the estimation of risk. The biological factors that must be considered include incidence of tumors, latent period, degree of malignancy, and multiplicity of tumors. The risk of radiation induction of tumors is influenced by the genotype, sex, and age of the patient, the tissues that will be exposed, and previous therapy. With chemotherapy the number of cells at risk is usually markedly higher than with radiation therapy. Clearly the problem of the estimation of comparative risks is complex. This paper presents the current views on the comparative risks and the importance of the various factors that influence the estimation of risk.

  5. Radiation acoustics

    CERN Document Server

    Lyamshev, Leonid M

    2004-01-01

    Radiation acoustics is a developing field lying at the intersection of acoustics, high-energy physics, nuclear physics, and condensed matter physics. Radiation Acoustics is among the first books to address this promising field of study, and the first to collect all of the most significant results achieved since research in this area began in earnest in the 1970s.The book begins by reviewing the data on elementary particles, absorption of penetrating radiation in a substance, and the mechanisms of acoustic radiation excitation. The next seven chapters present a theoretical treatment of thermoradiation sound generation in condensed media under the action of modulated penetrating radiation and radiation pulses. The author explores particular features of the acoustic fields of moving thermoradiation sound sources, sound excitation by single high-energy particles, and the efficiency and optimal conditions of thermoradiation sound generation. Experimental results follow the theoretical discussions, and these clearl...

  6. Hawking radiation

    Science.gov (United States)

    Parentani, Renaud; Spindel, Philippe

    2011-12-01

    Hawking radiation is the thermal radiation predicted to be spontaneously emitted by black holes. It arises from the steady conversion of quantum vacuum fluctuations into pairs of particles, one of which escaping at infinity while the other is trapped inside the black hole horizon. It is named after the physicist Stephen Hawking who derived its existence in 1974. This radiation reduces the mass of black holes and is therefore also known as black hole evaporation.

  7. Investigation of coatings of austenitic steels produced by supersonic laser deposition

    Science.gov (United States)

    Gorunov, A. I.; Gilmutdinov, A. Kh.

    2017-02-01

    The structure and properties of stainless austenitic steel coatings obtained by the supersonic laser deposition are studied in the paper. Implantation of the powder particles into the substrate surface and simultaneous plastic deformation at partial melting improved the mechanical properties of the coatings - tensile strength limit was 650 MPa and adhesion strength was 105 MPa. It was shown that insufficient laser power leads to disruption of the deposition process stability and coating cracking. Surface temperature increase caused by laser heating above 1300 °C resulted in coating melting. The X-ray analysis showed that radiation intensifies the cold spray process and does not cause changes in the austenitic base structure.

  8. Effect of Coated PHB on Properties of Abradable Seal Coating

    Institute of Scientific and Technical Information of China (English)

    CHENG Xudong; XIANG Hongyu; YE Weiping; MENG Xiaoming; MIN Jie; LIU Minzhi; ZHANG Pu; LU Wei

    2014-01-01

    As pore-forming materials, the coated poly-p-hydroxybenzoate(short for PHB) and h-BN can be applied in the preparation of abradable seal coatings at high temperature. The characteristics of coating such as morphology, thermal stability and composition were studied by SEM, EDS and FTIR. The results show that the modified PHB will change the remained carbon amount, porosity and pore morphology of the coating, which can affect the properties of coatings. If the pore is small enough in uniform distribution, the coating with 5 MPa bond strength, 30-55 HR45Y superficial hardness and certain of carbon can be suitable to well abradability.

  9. Method of sintering materials with microwave radiation

    Science.gov (United States)

    Kimrey, Jr., Harold D.; Holcombe, Jr., Cressie E.; Dykes, Norman L.

    1994-01-01

    A method of sintering ceramic materials following: A compacted article comprising inorganic particles coated with carbon is provided, the carbon providing improved microwave coupling. The compacted article is then heated by microwave radiation to a temperature and for a period of time sufficient to sinter the compacted article.

  10. 阴离子改性PUA紫外光固化胶粘剂的制备及性能%Preparation and properties of UV-curable anionic modified PUA adhesive

    Institute of Scientific and Technical Information of China (English)

    董俊伟; 李仙会; 白子文; 吴佳林

    2012-01-01

    以异佛尔酮二异氰酸酯(IPDI)、二羟甲基丁酸(DMBA)和聚四氢呋喃醚二醇(PTMG)等为主要原料,制得聚氨酯(PU)预聚体;然后将其与丙烯酸羟乙酯(HEA)反应,制得HEA封端的聚氨酯丙烯酸酯(PUA)预聚体;最后在PUA预聚体中加入中和剂等助剂,制备出阴离子改性PUA紫外光(UV)固化胶粘剂.研究结果表明:当w(DMBA中-COOH)=1.2%(相对于PU预聚体质量而言)、中和度=n(中和剂):n(DMBA)=80%、以PTMG为多元醇且偶联剂采用预处理法加入时,相应的阴离子改性PUA型UV固化胶粘剂的耐水性、粘接强度和耐久性俱佳.%With isophorone diisocyanate (IPDI), dimethylol butyric acid(DMBA) and polytetrahydrofuran ether glycol(PTMG) as main raw materials,a polyurethane(PU) prepolymer was prepared,then a polyurethane acrylate (PUA) prepolymer with hydroxylethyl acrylate (HEA )-end was made by polymerization between PU prepolymer and HEA. Finally,an UV-curable anionic modified PUA adhesive was made by neutralizer and other additives introduced into PUA prepolymer. The research results showed that the corresponding UV-curable anionic modified PUA adhesive had good water resistance,bonding strength and durability when mass fraction of -COOH in DMBA was 1.2% in PU prepolymer,neutralization degree or molar ratio of re(neutralizer):n(DMBA) was 80%, PTMG was used as polyol and coupler was introduced into systems by pretreatment method.

  11. Alternative RPC Coatings

    Science.gov (United States)

    Strack, Jason

    2009-10-01

    The nuclear physics group at the University of Illinois is currently developing techniques to further improve the performance of Bakelite Resistive Plate Chambers (RPCs) for use as muon trigger detectors in experiments at hadron colliders. Muon trigger RPCs at LHC and RHIC typically use Bakelite plates coated with linseed oil. Both Bakelite and linseed oil, however, have high bulk and surface resistivity thus limiting the detection efficiency of the RPC at high rates. Experiments which dope the linseed oil with either carbon or copper are carried out with the goal to select targeted lower surface resistivity values for the coating applied to the Bakelite plates. Two doping procedures have been studied. In the first method a thin layer of graphite is deposited between the Bakelite and the linseed oil. For the second method the graphite or copper powder are deposited on top of the drying linseed oil coating. In this presentation the coating methods will be discussed and the effects of the coating on the RPC position resolution, cluster size and efficiencies will be discussed.

  12. Coatings for directional eutectics

    Science.gov (United States)

    Rairden, J. R.; Jackson, M. R.

    1976-01-01

    Coatings developed to provide oxidation protection for the directionally-solidified eutectic alloy NiTaC-B (4.4 weight percent Cr) were evaluated. Of seven Co-, Fe- and Ni-base coatings that were initially investigated, best resistance to cyclic oxidation was demonstrated by duplex coatings fabricated by depositing a layer of NiCrAl(Y) by vacuum evaporation from an electron beam source followed by deposition of an Al overlayer using the pack cementation process. It was found that addition of carbon to the coating alloy substantially eliminated the problem of fiber denudation in TaC-type eutectic alloys. Burner rig cycled NiTaC-B samples coated with Ni-20Cr-5Al-0.1C-0.1Y+Al and rupture-tested at 1100 deg C performed as well as or better than uncoated, vacuum cycled and air-tested NiTaC-13; however, a slight degradation with respect to uncoated material was noted in air-stress rupture tests at 870 deg C for both cycled and uncycled samples.

  13. Based Adaptive Nanocomposite Coatings

    Science.gov (United States)

    Ramazani, M.; Ashrafizadeh, F.; Mozaffarinia, R.

    2014-08-01

    A promising Ni(Al)-Cr2O3-Ag-CNT-WS2 self-lubricating wear-resistant coating was deposited via atmospheric plasma spray of Ni(Al), nano Cr2O3, nano silver and nano WS2 powders, and CNTs. Feedstock powders with various compositions prepared by spray drying were plasma sprayed onto carbon steel substrates. The tribological properties of coatings were tested by a high temperature tribometer in a dry environment from room temperature to 400 °C, and in a natural humid environment at room temperature. It was found that all nanocomposite coatings have better frictional behavior compared with pure Ni(Al) and Ni(Al)-Cr2O3 coatings; the specimen containing aproximately 7 vol.% Ag, CNT, and WS2 had the best frictional performance. The average room temperature friction coefficient of this coating was 0.36 in humid atmosphere, 0.32 in dry atmosphere, and about 0.3 at high temperature.

  14. Black carbon radiative forcing at TOA decreased during aging

    Science.gov (United States)

    Wu, Yu; Cheng, Tianhai; Zheng, Lijuan; Chen, Hao

    2016-12-01

    During aging processing, black carbon (also called soot) particles may tend to be mixed with other aerosols, and highly influence their radiative forcing. In this study, freshly emitted soot particles were simulated as fractal aggregates composed of small spherical primary monomers. After aging in the atmosphere, soot monomers were coated by a thinly layer of sulfate as thinly coated soot particles. These soot particles were entirely embedded into large sulfate particle by further aging, and becoming heavily coated soot particles. In clear-sky conditions, black carbon radiative forcing with different aging states were investigated for the bottom and top of atmosphere (BOA and TOA). The simulations showed that black carbon radiative forcing increased at BOA and decreased at TOA after their aging processes. Thinly and heavily coated states increased up to ~12% and ~35% black carbon radiative forcing at BOA, and black carbon radiative forcing at TOA can reach to ~20% and ~100% smaller for thinly and heavily coated states than those of freshly emitted states, respectively. The effect of aging states of black carbon radiative forcing was varied with surface albedo, aerosol optical depth and solar zenith angles. These findings would be helpful for the assessments of climate change.

  15. Radiation Shielding Systems Using Nanotechnology

    Science.gov (United States)

    Chen, Bin (Inventor); McKay, Christoper P. (Inventor)

    2011-01-01

    A system for shielding personnel and/or equipment from radiation particles. In one embodiment, a first substrate is connected to a first array or perpendicularly oriented metal-like fingers, and a second, electrically conducting substrate has an array of carbon nanostructure (CNS) fingers, coated with an electro-active polymer extending toward, but spaced apart from, the first substrate fingers. An electric current and electric charge discharge and dissipation system, connected to the second substrate, receives a current and/or voltage pulse initially generated when the first substrate receives incident radiation. In another embodiment, an array of CNSs is immersed in a first layer of hydrogen-rich polymers and in a second layer of metal-like material. In another embodiment, a one- or two-dimensional assembly of fibers containing CNSs embedded in a metal-like matrix serves as a radiation-protective fabric or body covering.

  16. Preliminary coating design and coating developments for ATHENA

    DEFF Research Database (Denmark)

    Jakobsen, Anders Clemen; Ferreira, Desiree Della Monica; Christensen, Finn Erland

    2011-01-01

    We present initial novel coating design for ATHENA. We make use of both simple bilayer coatings of Ir and B4C and more complex constant period multilayer coatings to enhance the effective area and cover the energy range from 0.1 to 10 keV. We also present the coating technology used for these des......We present initial novel coating design for ATHENA. We make use of both simple bilayer coatings of Ir and B4C and more complex constant period multilayer coatings to enhance the effective area and cover the energy range from 0.1 to 10 keV. We also present the coating technology used...

  17. Conservation of minimally processed pineapple using calcium chloride, edible coating and gamma radiation;Conservacao de abacaxi minimamente processado utilizando como coadjuvantes cloreto de calcio, pelicula comestivel e radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Pilon, Lucimeire

    2007-07-01

    The aim of this study was to obtain a convenience type pineapple subjected to fresh-cut process and calcium chloride, wheat gluten and alginate-base edible coating and irradiation treatments. The fruits were washed, sanitized with Sumaveg (Sodium Dichloro-s-Triazinetrione) in a 200 mg L-1 chlorine-free solution at 7 deg C for 15 minutes, and then manually peeled. The peeled fruits were sliced into 1 cm thick slices, rinsed in 20 mg L-1 chlorine-free solution for 3 minutes and drained for 3 minutes. In the first experiment, the samples were treated with: 1% calcium chloride + vital wheat gluten solution; 1% calcium chloride + 1% alginate solution; and control. In the second experiment, the samples were treated with: 1% calcium chloride + vital wheat gluten solution + 2.3 kGy; 1% calcium chloride + 2.3kGy; irradiation with 2.3kGy; and control. The packing consisted of rigid polyethylene terephthalate (PET) trays with around 250 g of fruit. The irradiation was performed in a Cobalt-60 multipurpose irradiator with 92 kCi activity and dose value of 2.3 kGy h-1. The samples were stored at 5 +- 1 deg C and evaluated every other day for 12 days. In the first experiment pH and titratable acidity values showed slight variations but were similar between the treatments. There was a decrease in ascorbic acid values in all treatments. Browning was noticed in all treatments over the storage period. Although the values between the treatments were similar, the pineapple treated with calcium chloride + gluten showed firmer texture, less liquid loss, and lower values of polyphenoloxidase and peroxidase activities and CO{sub 2} and ethylene production. Mesophiles and mold and yeast counts were also reduced. No Salmonella and E. coli were detected. Total coliform counts were low in all the treatments and appeared in just a few isolated samples during the storage period. Sensory analyses showed that the samples treated with calcium chloride + gluten had the lower scores for texture

  18. Reaching the Chu Lower Bound on Q With Magnetic Dipole Antennas Using a Magnetic-Coated PEC Core

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.; Breinbjerg, Olav

    2011-01-01

    We analytically solve the radiation problem for a spherical magnetic dipole antenna with a material-coated perfectly electrically conducting core. Using the closed-form expressions derived for the internal and external stored energies as well as for the radiation quality factor $Q$, we determine...... the optimal geometrical and material parameters of the antenna. We show that the optimal permeability of the coating increases as the coating becomes thinner; as a result, the energy stored in it and the radiation quality factor $Q$ reduce. In the limit of an infinitely thin coating, the optimal permeability...... tends to infinity, the internal stored energy vanishes, and the $Q$ reaches the Chu lower bound, irrespective of the antenna electrical size $ka$ and permittivity of the coating....

  19. Materials for solar-transmitting heat-reflecting coatings

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, B.; Valkonen, E.; Karlsson, T.; Ribbing, C.G.

    1981-11-27

    A coating for solar energy applications which combines heat reflection with transparency to solar radiation may be of four different types: a metallic film which is sufficiently thin to be transparent; a metal-based multilayer coating; a wide band gap heavily doped semiconductor such as SnO/sub 2/ or In/sub 2/O/sub 3/; a conducting microgrid. We prepared such coatings on glass by evaporating thin films of silver, copper, gold, aluminium, cobalt, iron, chromium and nickel of various thicknesses and by spraying SnO/sub 2/ films. The spectral variations in the transmittance, and the front side and back side reflectances were measured in the wavelength range 0.4-15..mu..m. The properties of a three-layer coating of the dielectric/metal/dielectric type were calculated with a multilayer program using known bulk optical constants. The effect of these films when coated onto a domestic window was demonstrated with a heat transfer calculation using an equivalent thermal net. When a large transmittance over a broad range of the solar spectrum is required, gold is an equally good, or a slightly better, choice than silver as the metal in a three-layer coating. In general, an SnO/sub 2/ film exhibits a higher solar transmittance as well as a higher emittance than a coating containing metals. This implies that the oxide is to be preferred as a coating on a window when the maximum passive solar heating is sought. However, a metal-based coating could be better when a very low Usub(L) value is the most important requirement.

  20. Optical Coatings Formed by Gradient Refractive Index Materials

    Directory of Open Access Journals (Sweden)

    Kęstutis Juškevičius

    2012-01-01

    Full Text Available Recent advances in ion beam sputtering technology enabled efficient deposition of different oxide mixture coatings. In the present investigation, coating materials ZrO2 and SiO2 were utilized for the synthesis of different mixtures. The goal of the conducted investigation was to explore the potential of ZrO2/SiO2 mixtures, especially for applications in the range of the UV spectral. Deposited dielectric mirrors having classical quarter-wave and “rised” design with ZrO2/SiO2 mixture for 266 nm and 355 nm showed good resistance to laser radiation.We also investigated the “fatigue” behavior of LIDT’s in LBO crystals with single, dual and triple wavelength anti-reflective coatings (AR@355, AR@532+1064 and AR@355+532+1064 in order to optimize design and layer materials. The influence of gradient refractive index profiles on damage resistance is of a special interest. We selected a few designs of antireflective coatings which demonstrated the best resistance to laser radiation.An experimental study on rugate filter coatings showed the need for a more accurate characterization of optical properties of metal oxides and their corresponding mixtures.Article in Lithuanian

  1. Multilayer coatings for optics in the extreme ultraviolet

    Science.gov (United States)

    Larruquert, Juan I.; Vidal-Dasilva, Manuela; García-Cortés, Sergio; Rodríguez-de Marcos, Luis; Fernández-Perea, Mónica; Aznárez, José A.; Méndez, José A.

    2011-02-01

    The strong absorption of materials in the extreme ultraviolet (EUV) above ~50 nm has precluded the development of efficient coatings. The development of novel coatings with improved EUV performance is presented. An extensive research was performed on the search and characterization of new materials with low absorption or high reflectance. Lanthanide series was found to be a source of materials with relatively low absorption in this range, where most materials in nature present a strong absorption. Other materials, such as SiO and B, have been found to have interesting properties for applications on EUV coatings. As a result, novel multilayers based on Yb, Al, and SiO have been developed with narrowband performance in the 50-92 nm range. In some cases, the difficulty of developing narrowband coatings in the EUV can be overcome by designing multilayers that address specific purposes, such as maximizing and/or minimizing the reflectance at two or more wavelengths or bands. In this direction, we are working towards the development of coatings that combine a relatively high reflectance in a desired EUV band with a low reflectance in another band, for applications in which the presence of the latter radiation may mask a weak EUV radiation source.

  2. Organic matrix composite protective coatings for space applications

    Science.gov (United States)

    Dursch, Harry W.; George, Pete

    1995-01-01

    Successful use of composites in low earth orbit (LEO) depends on their ability to survive long-term exposure to atomic oxygen (AO), ultraviolet radiation, charged particle radiation, thermal cycling, and micrometeoroid and space debris. The AO environment is especially severe for unprotected organic matrix composites surfaces in LEO. Ram facing unprotected graphite/epoxy flown on the 69-month Long Duration Exposure Facility (LDEF) mission lost up to one ply of thickness (5 mils) resulting in decreased mechanical properties. The expected AO fluence of the 30 year Space Station Alpha mission is approximately 20 times that seen on LDEF. This exposure would result in significant material loss of unprotected ram facing organic matrix composites. Several protective coatings for composites were flown on LDEF including anodized aluminum, vacuum deposited coatings, a variety of thermal control coatings, metalized Teflon, and leafing aluminum. Results from the testing and analysis of the coated and uncoated composite specimens flown on LDEF's leading and trailing edges provide the baseline for determining the effectiveness of protectively coated composites in LEO. In addition to LDEF results, results from shuttle flight experiments and ground based testing will be discussed.

  3. Application of radiation in Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Naiyyum Choudhury; Najmul Alam Chowdhury; Feroza Akhtar [Bangladesh Atomic Energy Commission, Dhaka (Bangladesh)

    2001-03-01

    Radiation technology offers a very wide scope for utilisation and commercial exploitation in various field. All over the world, this technology is being favourably considered for different applications like radiation sterilisation of medical products, preservation of food by controlling the physiological processes for extending shelf-life and eradication of microbial and insect pests, radiation processing of polymeric materials and treatment of sewage sludge. Bangladesh Atomic Energy Commission has taken radiation processing programmes in a big way right from its inception. This paper describes the studies carried out by various research groups in Bangladesh Atomic Energy Commission mainly using Cobalt-60 gamma radiation. The investigation covers medical sterilisation, food preservation and development and modification of polymeric materials by gamma radiation. Both food preservation and radiation sterilisation of medical products are now being commercially carried out in the Gammatech facility as a joint venture company of BAEC and a private entrepreneur. Bangladesh is soon going to establish a full-fledged Tissue Bank to cater the needs of various tissue allografts for surgical replacement. Recently Government of Bangladesh has allocated US$ 1.00 million for strengthening of the Tissue Banking Laboratory. BAEC has made quite a good research contribution on vulcanization of natural rubber latex, wood plastic composites, surface coating curing, polymer modification etc. As a result of successful achievement of R and D activities in all these projects, a pilot plant project involving about US$ 4.00 million is under implementation at the Atomic energy Research Establishment campus of BAEC. In addition a project on 'National Polymer Centre' at a cost of US$ 2.00 million has already been approved. It is expected that work on radiation processing including commercialization will be accelerated with the implementation of these projects. The impact of radiation

  4. Bioceramics for implant coatings

    Directory of Open Access Journals (Sweden)

    Allison A Campbell

    2003-11-01

    Early research in this field focused on understanding the biomechanical properties of metal implants, but recent work has turned toward improving the biological properties of these devices. This has led to the introduction of calcium phosphate (CaP bioceramics as a bioactive interface between the bulk metal impart and the surrounding tissue. The first CaP coatings were produced via vapor phase processes, but more recently solution-based and biomimetic methods have emerged. While each approach has its own intrinsic materials and biological properties, in general CaP coatings promise to improve implant biocompatibility and ultimately implant longevity.

  5. Advanced Coating Removal Techniques

    Science.gov (United States)

    Seibert, Jon

    2006-01-01

    An important step in the repair and protection against corrosion damage is the safe removal of the oxidation and protective coatings without further damaging the integrity of the substrate. Two such methods that are proving to be safe and effective in this task are liquid nitrogen and laser removal operations. Laser technology used for the removal of protective coatings is currently being researched and implemented in various areas of the aerospace industry. Delivering thousands of focused energy pulses, the laser ablates the coating surface by heating and dissolving the material applied to the substrate. The metal substrate will reflect the laser and redirect the energy to any remaining protective coating, thus preventing any collateral damage the substrate may suffer throughout the process. Liquid nitrogen jets are comparable to blasting with an ultra high-pressure water jet but without the residual liquid that requires collection and removal .As the liquid nitrogen reaches the surface it is transformed into gaseous nitrogen and reenters the atmosphere without any contamination to surrounding hardware. These innovative technologies simplify corrosion repair by eliminating hazardous chemicals and repetitive manual labor from the coating removal process. One very significant advantage is the reduction of particulate contamination exposure to personnel. With the removal of coatings adjacent to sensitive flight hardware, a benefit of each technique for the space program is that no contamination such as beads, water, or sanding residue is left behind when the job is finished. One primary concern is the safe removal of coatings from thin aluminum honeycomb face sheet. NASA recently conducted thermal testing on liquid nitrogen systems and found that no damage occurred on 1/6", aluminum substrates. Wright Patterson Air Force Base in conjunction with Boeing and NASA is currently testing the laser remOval technique for process qualification. Other applications of liquid

  6. Active Packaging Coatings

    Directory of Open Access Journals (Sweden)

    Luis J. Bastarrachea

    2015-11-01

    Full Text Available Active food packaging involves the packaging of foods with materials that provide an enhanced functionality, such as antimicrobial, antioxidant or biocatalytic functions. This can be achieved through the incorporation of active compounds into the matrix of the commonly used packaging materials, or by the application of coatings with the corresponding functionality through surface modification. The latter option offers the advantage of preserving the packaging materials’ bulk properties nearly intact. Herein, different coating technologies like embedding for controlled release, immobilization, layer-by-layer deposition, and photografting are explained and their potential application for active food packaging is explored and discussed.

  7. HA-Coated Implant

    DEFF Research Database (Denmark)

    Daugaard, Henrik; Søballe, Kjeld; Bechtold, Joan E

    2014-01-01

    The goal of osseointegration of orthopedic and dental implants is the rapid achievement of a mechanically stable and long lasting fixation between living bone and the implant surface. In total joint replacements of cementless designs, coatings of calcium phosphates were introduced as a means...... of improving the fixation of implants. Of these, hydroxyapatite (HA) is the most widely used and most extensively investigated. HA is highly osseoconductive, and the positive effect is well documented in both basic and long-term clinical research [1–6]. This chapter describes experimental and clinical studies...... evaluating bone-implant fixation with HA coatings....

  8. Tribology and coatings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    The future use of fuel-efficient, low-emission, advanced transportation systems (for example, those using low-heat-rejection diesel engines or advanced gas turbines) presents new challenges to tribologists and materials scientists. High service temperatures, corrosive environments, and extreme contact pressures are among the concerns that make necessary new tribological designs, novel materials, and effective lubrication concepts. Argonne is working on methods to reduce friction, wear and corrosion, such as soft metal coatings on ceramics, layered compounds, diamond coatings, and hard surfaces.

  9. Methods and means for coating paper by film coating

    NARCIS (Netherlands)

    van der Maarel, Marc; Ter Veer, Arend Berend Cornelis; Vrieling-Smit, Annet; Delnoye, Pierre

    2015-01-01

    This invention relates to the field of paper coating, more in particular to means and methods for providing paper with at least one layer of pigment using film coating to obtain a well printable surface. Provided is a method for preparing coated paper comprising the steps of: a) providing a pigmente

  10. Fixation of three-dimensional states of deformation in polymers by ionizing radiation - III. Experimental results and implementation

    Energy Technology Data Exchange (ETDEWEB)

    Schaudy, R.; Wendrinsky, J.; Beer, R.J.; Eberhardsteiner, J

    1998-06-01

    Photoelastic investigations using transparent polymeric materials are still a potential tool in mechanical engineering, in civil engineering and more recently in biomechanics. They allow the analysis of deformations or stresses even in complex three-dimensional bodies. In order to extend the application of such plastic models at ambient temperature it was necessary to improve the fixation of deformations in the loaded state. This could be realized by the study and proper modification of some radiation-curable polymer systems (Schaudy et al., 1995, 1996). The experimental results reveal a broad variety of properties due to the type of the polymer system and to the degree of crosslinking caused by the radiation dose applied. Simple spatial models are as well discussed as the industrial and scientific implementation of the new materials.

  11. Thermal barrier coating for alloy systems

    Science.gov (United States)

    Seals, Roland D.; White, Rickey L.; Dinwiddie, Ralph B.

    2000-01-01

    An alloy substrate is protected by a thermal barrier coating formed from a layer of metallic bond coat and a top coat formed from generally hollow ceramic particles dispersed in a matrix bonded to the bond coat.

  12. Optical coatings for fiber lasers

    Institute of Scientific and Technical Information of China (English)

    HONG Dong-mei; ZHU Zhen; YUE Wei

    2005-01-01

    Fiber laser is the future development direction for the high energy lasers. This paper describs two kinds of optical coatings for fiber laser, including long and short wave pass filters. The one characteristic of fiber laser coatings lies in that coatings should separate two closely wavelength light including laser pump wavelength (980 nm) and laser irradiation wavelength(1 050~1 100 nm). At the same time, the coatings should have high laser damage threshold.

  13. Active coated nano-particle excited by an arbitrarily located electric Hertzian dipole — resonance and transparency effects

    DEFF Research Database (Denmark)

    Arslanagic, Samel; Ziolkowski, Richard W.

    2010-01-01

    The present work investigates the optical properties of active coated spherical nano-particles excited by an arbitrarily located electric Hertzian dipole. The nano-particles are made of specific dielectric and plasmonic materials. The spatial near-field distribution as well as the normalized...... radiation resistance is examined. Both enhanced as well as reduced radiation effects are demonstrated. In particular, it is shown that specific active coated nano-particles can be designed to be resonant, leading to much larger values of the normalized radiation resistance than is the case...... with the corresponding passive coated nano-particles, thereby overcoming the intrinsic losses present in the plasmonic materials. Moreover, it is shown that other active coated nano-particle designs can significantly reduce the normalized radiation resistance; thus both the resonant as well as non...

  14. Coatings and Tints of Spectacle Lenses

    OpenAIRE

    H. Zeki Büyükyıldız

    2012-01-01

    Spectacle lenses are made of mineral or organic (plastic) materials. Various coatings and tints are applied to the spectacle lenses according to the characteristic of the lens material, and for the personal needs and cosmetic purpose. The coatings may be classified in seven groups: 1) Anti-reflection coatings, 2) Hard coatings, 3) Clean coat, 4) Mirror coatings, 5) Color tint coating (one of coloring processes), 6) Photochromic coating (one of photochromic processes), and 7) Anti-fog...

  15. Tribological characterization of selected hard coatings

    OpenAIRE

    Karlsson, Patrik

    2009-01-01

    Hard coatings are often used for protection of tool surfaces due to coating properties like low friction and high wear resistance. Even though many of the hard coatings have been tested for wear, it is important to try new wear test setups to fully understand tribological mechanisms and the potential of hard coatings. Few experiments have been performed with dual-coated systems where the sliding contact surfaces are coated with the same, or different, hard coating. The dual-coated system coul...

  16. Thin-Film Coated Detectors for Neutron Detection

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, Douglas S.; Gersch, Holly K.; Sanders, Jeffrey D.; Lindsay, John T. [Univ. of Michigan, Ann Arbor (United States); Klann, Raymond T. [Argonne National Lab., Argonne (United States)

    2001-09-15

    Semiconductor diode detectors coated with neutron reactive material are presently under investigation for various uses, such as remote sensing of thermal neutrons, fast neutron counting, and thermal neutron radiography. Theory indicates that single-coated devices can yield thermal neutron efficiencies from 4% to 11%, which is supported by experimental evidence. Radiation endurance measurements indicates that the devices function well up to a limiting thermal neutron fluence of 10{sup 13}/cm{sup 2}, beyond which noticeable degradation occurs. Thermal neutron contrast images of step wedges and simple phantoms, taken with dual in-line pixel devices, show promise for thermal neutron imaging detectors.

  17. Effect of an Opaque Reflecting Layer on the Thermal Behavior of a Thermal Barrier Coating

    Science.gov (United States)

    Spuckler, Charles M.

    2007-01-01

    A parametric study using a two-flux approximation of the radiative transfer equation was performed to examine the effects of an opaque reflective layer on the thermal behavior of a typical semitransparent thermal barrier coating on an opaque substrate. Some ceramic materials are semitransparent in the wavelength ranges where thermal radiation is important. Even with an opaque layer on each side of the semitransparent thermal barrier coating, scattering and absorption can have an effect on the heat transfer. In this work, a thermal barrier coating that is semitransparent up to a wavelength of 5 micrometers is considered. Above 5 micrometers wavelength, the thermal barrier coating is opaque. The absorption and scattering coefficient of the thermal barrier was varied. The thermal behavior of the thermal barrier coating with an opaque reflective layer is compared to a thermal barrier coating without the reflective layer. For a thicker thermal barrier coating with lower convective loading, which would be typical of a combustor liner, a reflective layer can significantly decrease the temperature in the thermal barrier coating and substrate if the scattering is weak or moderate and for strong scattering if the absorption is large. The layer without the reflective coating can be about as effective as the layer with the reflective coating if the absorption is small and the scattering strong. For low absorption, some temperatures in the thermal barrier coating system can be slightly higher with the reflective layer. For a thin thermal barrier coating with high convective loading, which would be typical of a blade or vane that sees the hot sections of the combustor, the reflective layer is not as effective. The reflective layer reduces the surface temperature of the reflective layer for all conditions considered. For weak and moderate scattering, the temperature of the TBC-substrate interface is reduced but for strong scattering, the temperature of the substrate is increased

  18. Rotatable fixture for spray coating

    Science.gov (United States)

    Katvala, V.; Porter, E.; Smith, M.

    1979-01-01

    Fixture that rotates about two axes ensures uniform coating and minimizes handling of coated workpiece. Each side of tile is coated in sequence by moving turntables until surface is perpendicular to spray. Process is repeated until desired thickness has built up.

  19. Coatings for transport industry

    Directory of Open Access Journals (Sweden)

    Krzysztof LUKASZKOWICZ

    2014-09-01

    Full Text Available The investigations concerned structural analysis, as well as mechanical properties and wear resistant of MeN/DLC double-layer coating deposited by hybrid PVD/PACVD method. In sliding dry friction conditions, after the break-in time, the friction coefficient for the investigated elements is set in the range between 0.03-0.06.

  20. Chitin-based coatings

    OpenAIRE

    1995-01-01

    A chitosan starting material is combined with a dilute organic acid to produce a chitosonium ion complex. The chitosonium ion complex is then cast, sprayed, extruded, or otherwise processed to produce filaments, coatings, fibers, or the like. Heat is then used to convert the chitosonium ion complex into a N-(C.sub.1-30)acyl glucose amine polymer.

  1. Metallography of Aluminide Coatings

    Science.gov (United States)

    1991-05-01

    Aero-Space Technologies Australia, Systems Division Librarian Ansett Airlines of Australia, Library Australian Airlines, Library Qantas Airways Limited...Fink, R, W. Heakel. " Analysis of Microstructural Change due to Cyclic Oxidation in Aluminilde-coated NI-Al. NI-Cr and NI-Cr-Al Alloys". High Temperature

  2. ATHENA optimized coating design

    DEFF Research Database (Denmark)

    Ferreira, Desiree Della Monica; Christensen, Finn Erland; Jakobsen, Anders Clemen

    2012-01-01

    The optimization of coating design for the ATHENA mission si described and the possibility of increasing the telescope effective area in the range between 0.1 and 10 keV is investigated. An independent computation of the on-axis effective area based on the mirror design of ATHENA is performed in ...

  3. Radiation Hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Castor, J I

    2003-10-16

    The discipline of radiation hydrodynamics is the branch of hydrodynamics in which the moving fluid absorbs and emits electromagnetic radiation, and in so doing modifies its dynamical behavior. That is, the net gain or loss of energy by parcels of the fluid material through absorption or emission of radiation are sufficient to change the pressure of the material, and therefore change its motion; alternatively, the net momentum exchange between radiation and matter may alter the motion of the matter directly. Ignoring the radiation contributions to energy and momentum will give a wrong prediction of the hydrodynamic motion when the correct description is radiation hydrodynamics. Of course, there are circumstances when a large quantity of radiation is present, yet can be ignored without causing the model to be in error. This happens when radiation from an exterior source streams through the problem, but the latter is so transparent that the energy and momentum coupling is negligible. Everything we say about radiation hydrodynamics applies equally well to neutrinos and photons (apart from the Einstein relations, specific to bosons), but in almost every area of astrophysics neutrino hydrodynamics is ignored, simply because the systems are exceedingly transparent to neutrinos, even though the energy flux in neutrinos may be substantial. Another place where we can do ''radiation hydrodynamics'' without using any sophisticated theory is deep within stars or other bodies, where the material is so opaque to the radiation that the mean free path of photons is entirely negligible compared with the size of the system, the distance over which any fluid quantity varies, and so on. In this case we can suppose that the radiation is in equilibrium with the matter locally, and its energy, pressure and momentum can be lumped in with those of the rest of the fluid. That is, it is no more necessary to distinguish photons from atoms, nuclei and electrons, than it is

  4. Thermal Performance of Building Roof with Infrared Reflective Coatings

    Institute of Scientific and Technical Information of China (English)

    SHEN Hui; TAN Hong-wei; KATSUO MIKI; LIU Xiao-yu

    2009-01-01

    This paper investigated the applicability and effects of infrared reflective coating on energy con-sumption of factory building in hot summer and warm winter zone. It first resorted to theoretical calculation, which demonstrated the beneficial effects of infrared reflective coating on reducing building energy consumption. Then it analyzed a field measurement done on two identical rooms respectively with ordinary coated roof and in-frared reflective coated roof from November 2006 to October 2007, on a 24h basis. The measured data include exterior and interior roof surface temperature, indoor air temperature, and indoor globe temperature. The relat-ed weather data is from a weather station near the measured area. The continuous measurement has been accom-plished in southern China, and the measured data indicate that roof surface temperature and heat gain are signifi-cantly decreased in summer while slight negative effects in winter are induced by adopting infrared reflective coating. Thus it is simple and applicable to reduce building energy consumption in this area by applying infrared reflective coating. Regress equation between reduced roof thermal property, such as surface temperature and heat gain, and reduction in absorbed solar radiation shows their highly linear relationship. Based on the mea-sured data, it is estimated that the reduced power consumption is 3.45 kWh/m2·month in June.

  5. Radiation Exposure

    Science.gov (United States)

    ... on to any children you have after the exposure. A lot of radiation over a short period, ... skin burns and reduced organ function. If the exposure is large enough, it can cause premature aging ...

  6. Radiation damage

    CERN Document Server

    Heijne, Erik H M; CERN. Geneva

    1998-01-01

    a) Radiation damage in organic materials. This series of lectures will give an overview of radiation effects on materials and components frequently used in accelerator engineering and experiments. Basic degradation phenomena will be presented for organic materials with comprehensive damage threshold doses for commonly used rubbers, thermoplastics, thermosets and composite materials. Some indications will be given for glass, scintillators and optical fibres. b) Radiation effects in semiconductor materials and devices. The major part of the time will be devoted to treat radiation effects in semiconductor sensors and the associated electronics, in particular displacement damage, interface and single event phenomena. Evaluation methods and practical aspects will be shown. Strategies will be developed for the survival of the materials under the expected environmental conditions of the LHC machine and detectors. I will describe profound revolution in our understanding of black holes and their relation to quantum me...

  7. Radiation Transport

    Energy Technology Data Exchange (ETDEWEB)

    Urbatsch, Todd James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-06-15

    We present an overview of radiation transport, covering terminology, blackbody raditation, opacities, Boltzmann transport theory, approximations to the transport equation. Next we introduce several transport methods. We present a section on Caseology, observing transport boundary layers. We briefly broach topics of software development, including verification and validation, and we close with a section on high energy-density experiments that highlight and support radiation transport.

  8. Radiation Protection

    Energy Technology Data Exchange (ETDEWEB)

    Loos, M

    2001-04-01

    Major achievements of SCK-CEN's Radiation Protection Department in 2000 are described. The main areas for R and D of the department remain neutron dosimetry and neutron activation analysis, safeguards information handling and non-destructive assay techniques. Further activities include low-level radioactivity measurements in environmental and biological samples and radiation protection research. Finally, achievements in decision strategy research and social sciences in nuclear research are reported.

  9. Advanced materials for radiation-cooled rockets

    Science.gov (United States)

    Reed, Brian; Biaglow, James; Schneider, Steven

    1993-01-01

    The most common material system currently used for low thrust, radiation-cooled rockets is a niobium alloy (C-103) with a fused silica coating (R-512A or R-512E) for oxidation protection. However, significant amounts of fuel film cooling are usually required to keep the material below its maximum operating temperature of 1370 C, degrading engine performance. Also the R-512 coating is subject to cracking and eventual spalling after repeated thermal cycling. A new class of high-temperature, oxidation-resistant materials are being developed for radiation-cooled rockets, with the thermal margin to reduce or eliminate fuel film cooling, while still exceeding the life of silicide-coated niobium. Rhenium coated with iridium is the most developed of these high-temperature materials. Efforts are on-going to develop 22 N, 62 N, and 440 N engines composed of these materials for apogee insertion, attitude control, and other functions. There is also a complimentary NASA and industry effort to determine the life limiting mechanisms and characterize the thermomechanical properties of these materials. Other material systems are also being studied which may offer more thermal margin and/or oxidation resistance, such as hafnium carbide/tantalum carbide matrix composites and ceramic oxide-coated iridium/rhenium chambers.

  10. Thermoplastic coating of carbon fibers

    Science.gov (United States)

    Edie, D. D.; Lickfield, G. C.; Drews, M. J.; Ellison, M. S.; Gantt, B. W.

    1989-01-01

    A process is being developed which evenly coats individual carbon fibers with thermoplastic polymers. In this novel, continuous coating process, the fiber tow bundle is first spread cover a series of convex rollers and then evenly coated with a fine powder of thermoplastic matrix polymer. Next, the fiber is heated internally by passing direct current through the powder coated fiber. The direct current is controlled to allow the carbon fiber temperature to slightly exceed the flow temperature of the matrix polymer. Analysis of the thermoplastic coated carbon fiber tows produced using this continuous process indicates that 30 to 70 vol pct fiber prepregs can be obtained.

  11. Infrared optical coatings in SITP

    Institute of Scientific and Technical Information of China (English)

    LIU Ding-quan; ZHANG Feng-shan

    2005-01-01

    Infrared optical coatings in SITP (Shanghai Institute of Technical Physics) mainly cover the spectrum range from 0.7 μm to 15 μm, and visible and near-UV range are also been included. The coatings are mainly used for metal-reflectance mirrors, Anti-reflection(AR) lens and windows, filters, and dichroic beam splitters. Coatings passed some dependability tests. These optical coated devices usually consist in a remote observing instrument. Most coating materials are commercial products. And one kind of special material PbTe is made by ourselves. Some main results of our research department are reported.

  12. Coatings for improved corrosion resistance

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.

    1992-05-01

    Several coating approaches are being developed to resist attack in coal-fired environments and thereby minimize corrosion of underlying substrate alloys and extend the time for onset of breakaway corrosion. In general, coating systems can be classified as either diffusion or overlay type, which are distinguished principally by the method of deposition and the structure of the resultant coating-substrate bond. The coating techniques examined are pack cementation, electrospark deposition, physical and chemical vapor deposition, plasma spray, and ion implantation. In addition, ceramic coatings are used in some applications.

  13. Thermoplastic coating of carbon fibers

    Science.gov (United States)

    Edie, D. D.; Lickfield, G. C.; Drews, M. J.; Ellison, M. S.; Gantt, B. W.

    1989-01-01

    A process is being developed which evenly coats individual carbon fibers with thermoplastic polymers. In this novel, continuous coating process, the fiber tow bundle is first spread cover a series of convex rollers and then evenly coated with a fine powder of thermoplastic matrix polymer. Next, the fiber is heated internally by passing direct current through the powder coated fiber. The direct current is controlled to allow the carbon fiber temperature to slightly exceed the flow temperature of the matrix polymer. Analysis of the thermoplastic coated carbon fiber tows produced using this continuous process indicates that 30 to 70 vol pct fiber prepregs can be obtained.

  14. Characteristics and properties of surface coated nano-TiO2

    Institute of Scientific and Technical Information of China (English)

    GAO Jia-cheng; ZOU Jian; TAN Xiao-wei; WANG Yong

    2006-01-01

    Nano-TiO2 was coated with Al2O3, SiO2 and silane coupling agent by chemical liquid deposition. The coating was characterized by Raman spectroscopy, XRD, TEM and FT-IR. The coating content and anti-ultraviolet capacity of nano-TiO2 were measured by XRF and UV-vis spectrometer. The results show that dense coatings containing 5% Al2O3 or SiO2 can be obtained by mixing slurry at pH 10, adding coating reagent and neutralization reagent into the slurry for 60 min at 85-95 ℃, and finally aging for 120 min. Noncrystal SiO2 was coated on the surface of nano-TiO2 to form silica gel polymer with a Ti-O-Si bond, while aluminum compound exists in the form of AlOOH and part Al(OH)3. The integrated dense film can shield photocatalysis effectively.The inorganic coating film can increase the wettability for xylene and stability in water. The surface modification of nano-TiO2 will not impair its ability for anti-ultraviolet radiation, and more short band ultraviolet radiation can be absorbed. In addition, the optimal coating amount of silane coupling agent should be less than 3% and the best wettability for xylene can be reached when the amount is 1.2%.

  15. Methods for Coating Particulate Material

    Science.gov (United States)

    Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)

    2013-01-01

    Methods and apparatus for coating particulate material are provided. The apparatus includes a vessel having a top and a bottom, a vertically extending conduit having an inlet in the vessel and an outlet outside of the vessel, a first fluid inlet in the bottom of the vessel for introducing a transfer fluid, a second fluid inlet in the bottom of the vessel for introducing a coating fluid, and a fluid outlet from the vessel. The method includes steps of agitating a material, contacting the material with a coating material, and drying the coating material to produce a coated material. The invention may be adapted to coat aerogel beads, among other materials. A coated aerogel bead and an aerogel-based insulation material are also disclosed.

  16. BIODEGRADABLE COATING FROM AGATHIS ALBA

    Directory of Open Access Journals (Sweden)

    NORYAWATI MULYONO

    2012-11-01

    Full Text Available The adhesive property of copal makes it as a potential coating onto aluminum foil to replace polyethylene. This research aimed to develop copal-based coating. The coating was prepared by extracting the copal in ethyl acetate and dipping the aluminium foil in ethyl acetate soluble extract of copal. The characterization of coating included its thickness, weight, thermal and chemical resistance, and biodegradation. The results showed that the coating thickness and weight increased as the copal concentration and dipping frequency increased. Thermal resistance test showed that the coating melted after being heated at 110°C for 30 min. Copal-based coating wasresistant to acidic solution (pH 4.0, water, and coconut oil, but was deteriorated in detergent 1% (w/v and basic solution (pH 10.0. Biodegradability test using Pseudomonas aeruginosa showed weight reduction of 76.82% in 30 days.

  17. Proppant backproduction during hydraulic fracturing -- A new failure mechanism for resin-coated proppants

    Energy Technology Data Exchange (ETDEWEB)

    Vreeburg, R.J.; Roodhart, L.P.; Davies, D.R.; Penny, G.S. (STIM-LAB Inc., Duncan, OK (United States))

    1994-10-01

    Backproduction of proppant from hydraulically fractured wells, particularly those completed in the northern European Rotliegend formation, is a major operational problem, necessitating costly and manpower-intensive surface-handling procedures. Further, the development of unmanned platform operations offshore, required in today's economic climate, is impossible as long as this problem remains unsolved. The most cost-effective potential solution to this problem is provided by curable resin-coated proppant (RCP), which consolidates in the fracture. Early field trials with RCP's, however, were not completely effective in stopping the backproduction of proppant. Typically, some 10% of the total volume of RCP placed in the fracture was backproduced. The authors performed a laboratory study to help clarify the effect of curing temperature, water production rate, proppant size, and stress cycling on the integrity of RCP packs. The experiments confirmed the field experience that stress cycling has a dramatic effect on proppant backproduction of commercial RCP packs. The number of applied stress cycles (i.e., the number of times the well is shut in) and the initial RCP pack strength appear to be the dominant factors that govern proppant backproduction. Dedicated experiments are therefore required to evaluate the use of RCP's to eliminate proppant backproduction for a particular field application.

  18. Synchrotron radiation with radiation reaction

    Science.gov (United States)

    Nelson, Robert W.; Wasserman, Ira

    1991-04-01

    A rigorous discussion is presented of the classical motion of a relativistic electron in a magnetic field and the resulting electromagnetic radiation when radiation reaction is important. In particular, for an electron injected with initial energy gamma(0), a systematic perturbative solution to the Lorentz-Dirac equation of motion is developed for field strengths satisfying gamma(0) B much less than 6 x 10 to the 15th G. A particularly accurate solution to the electron orbital motion in this regime is found and it is demonstrated how lowest-order corrections can be calculated. It is shown that the total energy-loss rate corresponds to what would be found using the exact Larmor power formula without including radiation reaction. Provided that the particle energy and field strength satisfy the same contraint, it is explicitly demonstrated that the intuitive prescription for calculating the time-integrated radiation spectrum described above is correct.

  19. Flow accelerated organic coating degradation

    Science.gov (United States)

    Zhou, Qixin

    Applying organic coatings is a common and the most cost effective way to protect metallic objects and structures from corrosion. Water entry into coating-metal interface is usually the main cause for the deterioration of organic coatings, which leads to coating delamination and underfilm corrosion. Recently, flowing fluids over sample surface have received attention due to their capability to accelerate material degradation. A plethora of works has focused on the flow induced metal corrosion, while few studies have investigated the flow accelerated organic coating degradation. Flowing fluids above coating surface affect corrosion by enhancing the water transport and abrading the surface due to fluid shear. Hence, it is of great importance to understand the influence of flowing fluids on the degradation of corrosion protective organic coatings. In this study, a pigmented marine coating and several clear coatings were exposed to the laminar flow and stationary immersion. The laminar flow was pressure driven and confined in a flow channel. A 3.5 wt% sodium chloride solution and pure water was employed as the working fluid with a variety of flow rates. The corrosion protective properties of organic coatings were monitored inline by Electrochemical Impedance Spectroscopy (EIS) measurement. Equivalent circuit models were employed to interpret the EIS spectra. The time evolution of coating resistance and capacitance obtained from the model was studied to demonstrate the coating degradation. Thickness, gloss, and other topography characterizations were conducted to facilitate the assessment of the corrosion. The working fluids were characterized by Fourier Transform Infrared Spectrometer (FTIR) and conductivity measurement. The influence of flow rate, fluid shear, fluid composition, and other effects in the coating degradation were investigated. We conclude that flowing fluid on the coating surface accelerates the transport of water, oxygen, and ions into the coating, as

  20. Abdominal radiation - discharge

    Science.gov (United States)

    Radiation - abdomen - discharge; Cancer - abdominal radiation; Lymphoma - abdominal radiation ... When you have radiation treatment for cancer, your body goes through changes. About 2 weeks after radiation treatment starts, you might notice changes ...

  1. Brain radiation - discharge

    Science.gov (United States)

    Radiation - brain - discharge; Cancer-brain radiation; Lymphoma - brain radiation; Leukemia - brain radiation ... Decadron) while you are getting radiation to the brain. It may make you hungrier, cause leg swelling ...

  2. Design of optical coatings

    Science.gov (United States)

    Gunkel, Claus W.

    1990-08-01

    A highly sophisticated antireflection coating and a cut-on-filter - designed by the Leitz program "RDP" - will be pointed out. The program runs on a VAX 8530 and allows to calculate reflectance, transmittance and phase of randomly polarized light which interacts with marginal surfaces. The number of layers is not limited. Some or even all layers are allowed to be anistropic. Up to four layers may be inhomogeneous both in refractive indices and absorption constants. At a time two thicknesses, two refractive indices and absorption constants as well as the angles of incidence may be varied independently in each run. The calculated values will be compared with the results of measurements. The antireflection coating is evaporated in a Balzers high vacuum evaporation plant, controlled by the process unit BPU 420, whereas the cut-on filter is evaporated in a Leybold box coater with Leycom III and two electron-beam guns.

  3. Superelastic Orthopedic Implant Coatings

    Science.gov (United States)

    Fournier, Eric; Devaney, Robert; Palmer, Matthew; Kramer, Joshua; El Khaja, Ragheb; Fonte, Matthew

    2014-07-01

    The demand for hip and knee replacement surgery is substantial and growing. Unfortunately, most joint replacement surgeries will fail within 10-25 years, thereby requiring an arduous, painful, and expensive revision surgery. To address this issue, a novel orthopedic implant coating material ("eXalt") has been developed. eXalt is comprised of super elastic nitinol wire that is knit into a three-dimensional spacer fabric structure. eXalt expands in vivo to conform to the implantation site and is porous to allow for bone ingrowth. The safety and efficacy of eXalt were evaluated through structural analysis, mechanical testing, and a rabbit implantation model. The results demonstrate that eXalt meets or exceeds the performance of current coating technologies with reduced micromotion, improved osseointegration, and stronger implant fixation in vivo.

  4. Permeability of edible coatings.

    Science.gov (United States)

    Mishra, B; Khatkar, B S; Garg, M K; Wilson, L A

    2010-01-01

    The permeabilities of water vapour, O2 and CO2 were determined for 18 coating formulations. Water vapour transmission rate ranged from 98.8 g/m(2).day (6% beeswax) to 758.0 g/m(2).day (1.5% carboxymethyl cellulose with glycerol). O2 permeability at 14 ± 1°C and 55 ± 5% RH ranged from 1.50 to 7.95 cm(3)cm cm(-2)s(-1)Pa(-1), with CO2 permeability 2 to 6 times as high. Permeability to noncondensable gases (O2 and CO2) was higher for hydrophobic (peanut oil followed by beeswax) coatings as compared to hydrophilic (whey protein concentrate and carboxymethyl cellulose).

  5. Permeability of edible coatings

    OpenAIRE

    B Mishra; Khatkar, B. S.; Garg, M. K.; Wilson, L.A.

    2010-01-01

    The permeabilities of water vapour, O2 and CO2 were determined for 18 coating formulations. Water vapour transmission rate ranged from 98.8 g/m2.day (6% beeswax) to 758.0 g/m2.day (1.5% carboxymethyl cellulose with glycerol). O2 permeability at 14 ± 1°C and 55 ± 5% RH ranged from 1.50 to 7.95 cm3cm cm−2s−1Pa−1, with CO2 permeability 2 to 6 times as high. Permeability to noncondensable gases (O2 and CO2) was higher for hydrophobic (peanut oil followed by beeswax) coatings as compared to hydrop...

  6. Photochromic mesoporous hybrid coatings

    Science.gov (United States)

    Raboin, L.; Matheron, M.; Gacoin, T.; Boilot, J.-P.

    2008-09-01

    Spirooxazine (SO) photochromic molecules were trapped in sol-gel matrices. In order to increase the colourability and improve mechanical properties of sol-gel photochromic films, we present an original strategy in which SO photochromic molecules were dispersed in mesoporous organized films using the impregnation technique. Well-ordered organosilicate mesoporous coatings with the 3D-hexagonal symmetry were prepared by the sol-gel technique. These robust mesoporous films, which contain high amounts of hydrophobic methyl groups at the pore surface, offer optimized environments for photochromic dyes dispersed by impregnation technique. After impregnation by a spirooxazine solution, the photochromic response is only slightly slower when compared with mesostructured or soft sol-gel matrices, showing that mesoporous organized hybrid matrix are good host for photochromic dyes. Moreover, the molecular loading in films is easily adjustable in a large range using multi-impregnation procedure and increasing the film thickness leading to coatings for optical switching devices.

  7. Self-Cleaning Coatings

    Science.gov (United States)

    2014-06-01

    vacuum suction flask was used to volatilize the extra thinner from the mixtures. 2.1.2.2 Procedures Removal of filler from PSX-700 The original PSX...employed in this research to activate and ensure proper dispersions of these functional particles into the coating system. It is anticipated that...clear part (the resin and solvent) of the tubes was poured into a vacuum flask, while the precipitate (filler) from the bottom of the tubes was

  8. Thermal barrier coating materials

    Directory of Open Access Journals (Sweden)

    David R. Clarke

    2005-06-01

    Full Text Available Improved thermal barrier coatings (TBCs will enable future gas turbines to operate at higher gas temperatures. Considerable effort is being invested, therefore, in identifying new materials with even better performance than the current industry standard, yttria-stabilized zirconia (YSZ. We review recent progress and suggest that an integrated strategy of experiment, intuitive arguments based on crystallography, and simulation may lead most rapidly to the development of new TBC materials.

  9. for zeolite coating

    Directory of Open Access Journals (Sweden)

    Carlos Renato Rambo

    2006-01-01

    Full Text Available Biotemplating is the processing of microcellular ceramics by reproduction of natural morphologies, where the microstructural features of the biotemplate are maintained in the biomorphic ceramic. Different biotemplates with distinct pore anatomies were used to produce biomorphic supports for the zeolite coating: wood, cardboard, sea-sponge and sisal. The biomorphic ceramics were produced by distinguished processing routes: Al-gas infiltration-reaction, liquid-metal infiltration, dip-coating and sol-gel synthesis, in order to produce nitrides, carbides and oxides, depending on the processing conditions. The zeolite coating was performed by hydrothermal growth of MFI-type (Silicalite-1 and ZSM-5 zeolite crystals onto the internal pore walls of the biomorphic templates. The final biomorphic ceramic-zeolite composites were physically characterized, evaluated in terms of their gas adsorption capabilities and correlated to their microstructure and specific pore anatomy. The combination of the properties of the biomorphic ceramics with the adsorption properties of zeolites results in materials with distinct properties as potential candidates for adsorption and catalytic applications due to their characteristic porosity, molecular sieving capabilities and high thermo-mechanical strength.

  10. Decoding white coat hypertension.

    Science.gov (United States)

    Bloomfield, Dennis A; Park, Alex

    2017-03-16

    There is arguably no less understood or more intriguing problem in hypertension that the "white coat" condition, the standard concept of which is significantly blood pressure reading obtained by medical personnel of authoritative standing than that obtained by more junior and less authoritative personnel and by the patients themselves. Using hospital-initiated ambulatory blood pressure monitoring, the while effect manifests as initial and ending pressure elevations, and, in treated patients, a low daytime profile. The effect is essentially systolic. Pure diastolic white coat hypertension appears to be exceedingly rare. On the basis of the studies, we believe that the white coat phenomenon is a common, periodic, neuro-endocrine reflex conditioned by anticipation of having the blood pressure taken and the fear of what this measurement may indicate concerning future illness. It does not change with time, or with prolonged association with the physician, particularly with advancing years, it may be superimposed upon essential hypertension, and in patients receiving hypertensive medication, blunting of the nighttime dip, which occurs in about half the patients, may be a compensatory mechanisms, rather than an indication of cardiovascular risk. Rather than the blunted dip, the morning surge or the widened pulse pressure, cardiovascular risk appears to be related to elevation of the average night time pressure.

  11. High emittance black nickel coating on copper substrate for space applications

    Energy Technology Data Exchange (ETDEWEB)

    Somasundaram, Soniya, E-mail: jrf0013@isac.gov.in; Pillai, Anju M., E-mail: anjum@isac.gov.in; Rajendra, A., E-mail: rajendra@isac.gov.in; Sharma, A.K., E-mail: aks@isac.gov.in

    2015-09-15

    Highlights: • High emittance black nickel coating is obtained on copper substrate. • The effect of various process parameters on IR emittance is studied systematically. • Process parameters are optimized to develop a high emittance black nickel coating. • Coating obtained using the finalized parameters exhibited an emittance of 0.83. • SEM and EDAX are used for coating characterization. - Abstract: Black nickel, an alloy coating of zinc and nickel, is obtained on copper substrate by pulse electrodeposition from a modified Fishlock bath containing nickel sulphate, nickel ammonium sulphate, zinc sulphate and ammonium thiocyanate. A nickel undercoat of 4–5 μm thickness is obtained using Watts bath to increase the corrosion resistance and adhesion of the black nickel coating. The effect of bath composition, temperature, solution pH, current density and plating time on the coating appearance and corresponding infra-red emittance of the coating is investigated systematically. Process parameters are optimized to develop a high emittance space worthy black nickel coating to improve the heat radiation characteristics. The effect of the chemistry of the plating bath on the coating composition was studied using energy dispersive X-ray analysis (EDAX) of the coatings. The 5–6 μm thick uniform jet black zinc–nickel alloy coating obtained with optimized process exhibited an emittance of 0.83 and an absorbance of 0.92. The zinc to nickel ratio of black nickel coatings showing high emittance and appealing appearance was found to be in the range 2.3–2.4.

  12. High-temperature protective coatings on superalloys

    Institute of Scientific and Technical Information of China (English)

    刘培生; 梁开明; 周宏余

    2002-01-01

    Protective coatings are essential for superalloys to serve as blades of gas turb ines at high temperatures, and they primarily include aluminide coating, MCrAlY overlay coating, thermal barrier coating and microcrystalline coating. In this paper, all these high-temperature coatings are reviewed as well as their preparing techniques. Based on the most application and the main failure way, the importance is then presented for further deepgoing study on the high-temperature oxidation law of aluminide coatings.

  13. Coating and curing apparatus and methods

    Energy Technology Data Exchange (ETDEWEB)

    Brophy, Brenor L.; Gonsalves, Peter R.; Maghsoodi, Sina; Colson, Thomas E.; Yang, Yu S.; Abrams, Ze' ev R.

    2016-04-19

    Disclosed is a coating apparatus including flow coating and roll-coating that may be used for uniform sol-gel coating of substrates such as glass, solar panels, windows or part of an electronic display. Also disclosed are methods for substrate preparation, flow coating and roll coating. Lastly, systems and methods for curing sol-gel coatings deposited onto the surface of glass substrates using high temperature air-knives, infrared emitters and direct heat applicators are disclosed.

  14. Reduction of Temperature in Concentrator Photovoltaic Module Using Coating with High Thermal Emissivity and Conductivity

    Directory of Open Access Journals (Sweden)

    Nakamura Satoshi

    2016-01-01

    Full Text Available The temperature of solar cells considerably increases under light-concentrating operations, and the conversion efficiency of solar cells decreases with increasing temperature. It is very important to reduce the cell temperature in concentrator photovoltaic modules. The thermal radiation layers with high thermal emissivity and thermal conductivity was coated on the aluminum samples which is used for the chassis of concentrator photovoltaic and the effect was evaluated under the conditions with wind. The temperature of sample with coating showed lower temperature than that without coating. In the condition with wind, the coated sample with high thermal emissivity and high thermal conductivity showed the lowest temperature due to the effect of thermal radiation and thermal conduction.

  15. A New Coating Process for Production of Coated Magnesium Powders

    Science.gov (United States)

    2008-04-16

    TGA data for magnesium hydroxide content. TGA analysis of the as-coated powders is a reproducible and accurate method for the determination of... TGA analysis of the as-coated powder, there is approximately 3wt% magnesium hydroxide present in the material due to the process variation compared...11: Magnesium hydroxide content as measured by TGA analysis for the 1-lb batches of as-coated ground powder Figure 12: Nitrometer analysis of

  16. Directional radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Dowell, Jonathan L.

    2017-09-12

    Directional radiation detectors and systems, methods, and computer-readable media for using directional radiation detectors to locate a radiation source are provided herein. A directional radiation detector includes a radiation sensor. A radiation attenuator partially surrounds the radiation sensor and defines an aperture through which incident radiation is received by the radiation sensor. The aperture is positioned such that when incident radiation is received directly through the aperture and by the radiation sensor, a source of the incident radiation is located within a solid angle defined by the aperture. The radiation sensor senses at least one of alpha particles, beta particles, gamma particles, or neutrons.

  17. Thermal radiation antennas made of multilayer structures containing negative index metamaterials

    NARCIS (Netherlands)

    Maksimovic, M.; Hammer, M.; Jaksic, Z.; Greiner, C.M.; Waechter, C.A.

    2008-01-01

    We investigate the thermal antenna behavior of emissive/absorptive substrates coated by passive optical multilayer systems that contain negative refractive index metamaterials (NIM). Spectral and angular distributions of the thermal radiation emittance for periodic defect-containing multilayer with

  18. Thermal radiation antennas made of multilayer structures containing negative index metamaterials

    NARCIS (Netherlands)

    Maksimovic, Milan; Lohmeyer, Manfred; Jaksic, Z.; Greiner, C.M.; Waechter, C.A.

    2008-01-01

    We investigate the thermal antenna behavior of emissive/absorptive substrates coated by passive optical multilayer systems that contain negative refractive index metamaterials (NIM). Spectral and angular distributions of the thermal radiation emittance for periodic defect-containing multilayer with

  19. Dense protective coatings, methods for their preparation and coated articles

    Energy Technology Data Exchange (ETDEWEB)

    Tulyani, Sonia; Bhatia, Tania; Smeggil, John G.

    2015-12-29

    A method for depositing a protective coating on a complex shaped substrate includes the steps of: (1) dipping a complex shaped substrate into a slurry to form a base coat thereon, the slurry comprising an aqueous solution, at least one refractory metal oxide, and at least one transient fluid additive present in an amount of about 0.1 percent to 10 percent by weight of the slurry; (2) curing the dipped substrate; (3) dipping the substrate into a precursor solution to form a top barrier coat thereon; and (4) heat treating the dipped, cured substrate to form a protective coating.

  20. Nanoparticle/Polymer Nanocomposite Bond Coat or Coating

    Science.gov (United States)

    Miller, Sandi G.

    2011-01-01

    This innovation addresses the problem of coatings (meant to reduce gas permeation) applied to polymer matrix composites spalling off in service due to incompatibility with the polymer matrix. A bond coat/coating has been created that uses chemically functionalized nanoparticles (either clay or graphene) to create a barrier film that bonds well to the matrix resin, and provides an outstanding barrier to gas permeation. There is interest in applying clay nanoparticles as a coating/bond coat to a polymer matrix composite. Often, nanoclays are chemically functionalized with an organic compound intended to facilitate dispersion of the clay in a matrix. That organic modifier generally degrades at the processing temperature of many high-temperature polymers, rendering the clay useless as a nano-additive to high-temperature polymers. However, this innovation includes the use of organic compounds compatible with hightemperature polymer matrix, and is suitable for nanoclay functionalization, the preparation of that clay into a coating/bondcoat for high-temperature polymers, the use of the clay as a coating for composites that do not have a hightemperature requirement, and a comparable approach to the preparation of graphene coatings/bond coats for polymer matrix composites.

  1. Orbital dynamics of a solar sail accelerated by thermal desorption of coatings

    OpenAIRE

    2016-01-01

    In this study we considered a solar sail coated with materials that undergo thermal desorption at a specific temperature, as a result of heating by solar radiation at a particular heliocentric distance. Three different scenarios, that only differ in the way the sail approaches the Sun, were analyzed and compared. In every case once the perihelion is reached, the sail coat undergoes thermal desorption. When the desorption process ends, the sail then escapes the Solar System having the conventi...

  2. Thin film design for advanced thermochromic smart radiator devices

    Institute of Scientific and Technical Information of China (English)

    Feng Yu-Dong; Wang Zhi-Min; Ma Ya-Li; Zhang Fu-Jia

    2007-01-01

    This paper describes the research on the materials and design methods for advanced smart radiator devices (SRDs) on large-area flexible substrates utilized on spacecraft. The functional material is thermochromic vanadium dioxide. The coating design of 3RD is similar to the design of broadband filter coatings in a mid-infrared region. The multilayer coatings have complex structures. Coating materials must be highly transparent in a required spectrum region and also mechanically robust enough to endure the influence from the rigorous environments of outer space. The number of layers must be very small, suitable for the deposition on large-area flexible substrates. All the coatings are designed initially based on optical calculation and practical experience, and then optimized by the TFCALC software. Several designs are described and compared with each other. The results show that the emittance variability of the designed SRDs is great than 400%, more advanced than the reported ones.

  3. Low Conductivity Thermal Barrier Coatings

    Science.gov (United States)

    Zhu, Dong-Ming

    2005-01-01

    Thermal barrier coatings will be more aggressively designed to protect gas turbine engine hot-section components in order to meet future engine higher fuel efficiency and lower emission goals. In this presentation, thermal barrier coating development considerations and requirements will be discussed. An experimental approach is established to monitor in real time the thermal conductivity of the coating systems subjected to high-heat-flux, steady-state and cyclic temperature gradients. Advanced low conductivity thermal barrier coatings have also been developed using a multi-component defect clustering approach, and shown to have improved thermal stability. The durability and erosion resistance of low conductivity thermal barrier coatings have been improved utilizing advanced coating architecture design, composition optimization, in conjunction with more sophisticated modeling and design tools.

  4. Pipeline integrity : control by coatings

    Energy Technology Data Exchange (ETDEWEB)

    Khanna, A.S. [Indian Inst. of Technology, Bombay (India)

    2008-07-01

    This presentation provided background information on the history of cross-country pipelines in India. It discussed the major use of gas. The key users were described as being the power and fertilizer industries, followed by vehicles using compressed natural gas to replace liquid fuels and thereby reduce pollution. The presentation also addressed the integrity of pipelines in terms of high production, safety, and monitoring. Integrity issues of pipelines were discussed with reference to basic design, control of corrosion, and periodic health monitoring. Other topics that were outlined included integrity by corrosion control; integrity by health monitoring; coatings requirements; classification of UCC pipeline coatings; and how the pipeline integrity approach can help to achieve coatings which give design life without any failure. Surface cleanliness, coating conditions, and the relationship between temperature of Epoxy coating and the time of adhesive coating were also discussed. Last, the presentation provided the results of an audit of the HBJ pipeline conducted from 1999 to 2000. tabs., figs.

  5. Terahertz pulsed imaging as an advanced characterisation tool for film coatings--a review.

    Science.gov (United States)

    Haaser, Miriam; Gordon, Keith C; Strachan, Clare J; Rades, Thomas

    2013-12-05

    Solid dosage forms are the pharmaceutical drug delivery systems of choice for oral drug delivery. These solid dosage forms are often coated to modify the physico-chemical properties of the active pharmaceutical ingredients (APIs), in particular to alter release kinetics. Since the product performance of coated dosage forms is a function of their critical coating attributes, including coating thickness, uniformity, and density, more advanced quality control techniques than weight gain are required. A recently introduced non-destructive method to quantitatively characterise coating quality is terahertz pulsed imaging (TPI). The ability of terahertz radiation to penetrate many pharmaceutical materials enables structural features of coated solid dosage forms to be probed at depth, which is not readily achievable with other established imaging techniques, e.g. near-infrared (NIR) and Raman spectroscopy. In this review TPI is introduced and various applications of the technique in pharmaceutical coating analysis are discussed. These include evaluation of coating thickness, uniformity, surface morphology, density, defects and buried structures as well as correlation between TPI measurements and drug release performance, coating process monitoring and scale up. Furthermore, challenges and limitations of the technique are discussed.

  6. Cherenkov radiation; La radiation Cerenkov

    Energy Technology Data Exchange (ETDEWEB)

    Hubert, P. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    When the radioactivity has been discovered, it was observed by researchers that different materials as mineral salts or solutions were emitting a weak light when submitted to radioactivity beams. At the beginning it has been thought that it was fluorescent light. In 1934, Cherenkov, a russian physicist, worked on the luminescence of uranyl salts solutions caused by gamma radiation and observed a very weak light was emitted by pure liquid. After further studies, he concluded that this phenomena was different from fluorescence. Since then, it has been called Cherenkov effect. This blue light emission is produced when charged particles are going through a transparent medium with an upper velocity than light velocity. This can happen only in medium with large refractive index as water or glass. It also presents its different properties discovered afterwards. The different applications of the Cherenkov radiation are discussed as counting techniques for radiation detectors or comic ray detectors. (M.P.)

  7. Influence of the reactive diluent on electron beam curable funtionalized N-(4-hydroxyl phenyl) maleimide derivatives – Studies on thermal degradation kinetics using model free approach

    Energy Technology Data Exchange (ETDEWEB)

    Pitchaimari, G. [Department of Polymer Technology, Kamaraj College of Engineering and Technology, S.P.G.C. Nagar, K. Vellakulam, Tamil Nadu 625 701 (India); Sarma, K.S.S.; Varshney, Lalit [Radiation Technology Development Section, Bhabha Atomic Research Centre, Mumbai 400085 (India); Vijayakumar, C.T., E-mail: ctvijay22@yahoo.com [Department of Polymer Technology, Kamaraj College of Engineering and Technology, S.P.G.C. Nagar, K. Vellakulam, Tamil Nadu 625 701 (India)

    2014-12-10

    Highlights: • Materials with maleimide and NVP ratio of 80:20 show better thermal stability. • The initial degradation temperatures are high at higher NVP concentration. • The E{sub a} values for ENVP are low compared to other materials investigated. • Polymers derived from DCNX needs highest E{sub a} value. • Cyanate ester functionalized materials offers better thermal stability. - Abstract: Electron beam curing of N-(4-acryloyloxy phenyl) maleimide, N-(4-methacryloyloxy phenyl) maleimide, and N-(4-cyanato phenyl) maleimide with different concentrations (80:20, 60:40, 40:60, and 20:80) of the reactive diluent N-vinylpyrrolidone (NVP) and pure NVP were investigated. The structures of all the polymers prepared were confirmed by FTIR studies and to understand the effect of the diluent concentration on the thermal stabilities of the E-beam cured polymers detailed thermogravimetric analyses were carried out. The thermal degradation kinetics is investigated using Vyazovkin, Flynn–Wall–Ozawa and Friedman methods. Of all the liquid compositions investigated materials with functionalized maleimide to NVP concentration in the ratio of 80:20 need highest activation energies for the thermal degradation and are found to have better thermal stabilities. The composition N-(4-cyanato phenyl) maleimide (80%) and NVP (20%) cured by E-beam radiation (400 kGy) lead to thermoset which showed the highest char value (30%) at 600 °C in nitrogen atmosphere.

  8. Thermal conductivity of thermal barrier coatings

    Energy Technology Data Exchange (ETDEWEB)

    Klemens, P.G.; Gell, M. [Connecticut Univ., Storrs, CT (United States). Inst. of Materials Science

    1998-05-01

    In thermal barrier coatings and other ceramic oxides, heat is conducted by lattice waves, and also by a radiative component which becomes significant at high temperatures. The theory of heat conduction by lattice waves is reviewed in the equipartition limit (above room temperature). The conductivity is composed of contributions from a spectrum of waves, determined by the frequency dependent attenuation length. Interaction between lattice waves (intrinsic processes), scattering by atomic scale point defects and scattering by extended imperfections such as grain boundaries, each limit the attenuation length in different parts of the spectrum. Intrinsic processes yield a spectral conductivity which is independent of frequency. Point defects reduce the contribution of the high frequency spectrum, grain boundaries and other extended defects that of the low frequencies. These reductions are usually independent of each other. Estimates will be given for zirconia containing 7wt% Y{sub 2}O{sub 3}, and for yttrium aluminum garnet. They will be compared to measurements. The effects of grain size, cracks and porosity will be discussed both for the lattice and the radiative components. While the lattice component of the thermal conductivity is reduced substantially by decreasing the grain size to nanometers, the radiative component requires pores or other inclusions of micrometer scale. (orig.) 9 refs.

  9. Functional Coatings with Polymer Brushes

    OpenAIRE

    König, Meike

    2013-01-01

    The scope of this work is to fathom different possibilities to create functional coatings with polymer brushes. The immobilization of nanoparticles and enzymes is investigated, as well as the affection of their properties by the stimuli-responsiveness of the brushes. Another aspect is the coating of 3D-nanostructures by polymer brushes and the investigation of the resulting functional properties of the hybrid material. The polymer brush coatings are characterized by a variety of microscopic a...

  10. Radiation Technology Against Bioterrorism

    Science.gov (United States)

    2004-10-25

    application of radiation processing: radiation crosslinking of polymers and radiation sterilization of health care products have developed into substantial...municipal waste water, • radiation inactivation of bioterrorism agents, • electron beam processing of flue gases, • radiation crosslinking , • radiation...Electron beam processing of flue gases 6. Radiation crosslinking 7. Radiation curing 3 Radiation Technology Against Bioterrorism L.G. Gazsó and G

  11. Post Irradiation Evaluation of Thermal Control Coatings and Solid Lubricants to Support Fission Surface Power Systems

    Science.gov (United States)

    Bowman, Cheryl L.; Jaworske, Donald A.; Stanford, Malcolm K.; Persinger, Justin A.; Khorsandi, Behrooz; Blue, Thomas E.

    2007-01-01

    The development of a nuclear power system for space missions, such as the Jupiter Icy Moons Orbiter or a lunar outpost, requires substantially more compact reactor design than conventional terrestrial systems. In order to minimize shielding requirements and hence system weight, the radiation tolerance of component materials within the power conversion and heat rejection systems must be defined. Two classes of coatings, thermal control paints and solid lubricants, were identified as material systems for which limited radiation hardness information was available. Screening studies were designed to explore candidate coatings under a predominately fast neutron spectrum. The Ohio State Research Reactor Facility staff performed irradiation in a well characterized, mixed energy spectrum and performed post irradiation analysis of representative coatings for thermal control and solid lubricant applications. Thermal control paints were evaluated for 1 MeV equivalent fluences from 1013 to 1015 n/cm2. No optical degradation was noted although some adhesive degradation was found at higher fluence levels. Solid lubricant coatings were evaluated for 1 MeV equivalent fluences from 1015 to 1016 n/cm2 with coating adhesion and flexibility used for post irradiation evaluation screening. The exposures studied did not lead to obvious property degradation indicating the coatings would have survived the radiation environment for the previously proposed Jupiter mission. The results are also applicable to space power development programs such as fission surface power for future lunar and Mars missions.

  12. Post Irradiation Evaluation of Thermal Control Coatings and Solid Lubricants to Support Fission Surface Power Systems

    Science.gov (United States)

    Bowman, Cheryl L.; Jaworske, Donald A.; Stanford, Malcolm K.; Persinger, Justin A.; Khorsandi, Behrooz; Blue, Thomas E.

    2007-01-01

    The development of a nuclear power system for space missions, such as the Jupiter Icy Moons Orbiter or a lunar outpost, requires substantially more compact reactor design than conventional terrestrial systems. In order to minimize shielding requirements and hence system weight, the radiation tolerance of component materials within the power conversion and heat rejection systems must be defined. Two classes of coatings, thermal control paints and solid lubricants, were identified as material systems for which limited radiation hardness information was available. Screening studies were designed to explore candidate coatings under a predominately fast neutron spectrum. The Ohio State Research Reactor Facility staff performed irradiation in a well characterized, mixed energy spectrum and performed post irradiation analysis of representative coatings for thermal control and solid lubricant applications. Thermal control paints were evaluated for 1 MeV equivalent fluences from 10(exp 13) to 10(exp 15) n per square centimeters. No optical degradation was noted although some adhesive degradation was found at higher fluence levels. Solid lubricant coatings were evaluated for 1 MeV equivalent fluences from 10(exp 15) to 10(exp 16) n per square centimeters with coating adhesion and flexibility used for post irradiation evaluation screening. The exposures studied did not lead to obvious property degradation indicating the coatings would have survived the radiation environment for the previously proposed Jupiter mission. The results are also applicable to space power development programs such as fission surface power for future lunar and Mars missions.

  13. Article Including Environmental Barrier Coating System

    Science.gov (United States)

    Lee, Kang N. (Inventor)

    2015-01-01

    An enhanced environmental barrier coating for a silicon containing substrate. The enhanced barrier coating may include a bond coat doped with at least one of an alkali metal oxide and an alkali earth metal oxide. The enhanced barrier coating may include a composite mullite bond coat including BSAS and another distinct second phase oxide applied over said surface.

  14. Chemical state analysis of conversion coatings by SR-XPS and TEY-XANES

    CERN Document Server

    Noro, H; Nagoshi, M

    2002-01-01

    Chromate coatings on galvanized steel have been studied by Synchrotron Radiation (SR) based techniques that include X-ray Photoelectron Spectroscopy (XPS) and Total-Electron-Yield X-ray Absorption Near Edge Structure (TEY-XANES). Non-destructive depth profiling of the coatings by SR-XPS reveals the enhancement of Cr sup 6 sup + in the outer surface. TEY-XANES spectroscopy based on simple specimen current measurement is demonstrated as an effective technique for analyzing chemical states of conversion coatings on general bulk substrates. The sampling depth of this technique, which exceeds several tens of nanometer, is determined by the penetration length of Auger electrons excited by X-ray and the inelastic mean free path of secondary electrons excited by inelastically scattered Auger electrons. The chemical states of phosphoric acid added chromate coatings are studied using this technique. The phosphoric acid is taken into the chromate coatings as partially changed into zinc and chromium phosphates, and the r...

  15. Structure and Corrosion Resistance of Microarc Oxidation Coatings on AZ91D Magnesium Alloy

    Institute of Scientific and Technical Information of China (English)

    Cui Shihai; Han Jianmin; Li Weijing; Li Ronghua; Zhu Xiaowen; Wang Jinhua

    2004-01-01

    Magnesium alloys are widely used as shells of 3C (computer, mobile phone and consumer electronics) equipments for its impressive mechanical and physical properties, such as low density, good resistance to electromagnetic radiation, suitable for high pressure diecasting and easily recycling, etc. But poor corrosion resistance confines its extensively application. In this paper, protective coatings was successfully prepared on AZ91D magnesium alloys by micro-arc oxidation (MAO) and painting process. Microstructures and phases of MAO coatings were invesgated with scanning electron microscope (SEM) and X-Ray diffractometer. Mechanical properties of MAO coating, such as adhesive force and corrosion resistance, were also tested. Results showed that MAO coatings were a good base for painting process. MAO coatings with paint have good adhesive properties to base metal and excellent corrosion resistance. Micro-arc oxidation with painting process is a good kind of surface treatment to improve the corrosion resistance of mobile phone shell made of AZ91D magnesium alloys.

  16. The Study of Indicatrices of Space Object Coatings in a Controlled Laboratory Environment

    Science.gov (United States)

    Koshkin, N.; Burlak, N.; Petrov, M.; Strakhova, S.

    The indicatrices of light scattering by radiation balance coatings used on space objects (SO) were determined in the laboratory experiment in a controlled condition. The laboratory device for the physical simulation of photometric observations of space objects in orbit, which was used in this case to study optical properties of coating samples, is described. The features of light reflection off plane coating samples, including multi-layer insulation (MLI) blankets, metal surfaces coated with several layers of enamel EP-140, special polyacrylate enamel AK-512 and matte finish Tp-CO-2, were determined. The indicated coatings are compound reflectors which exhibit both diffuse and specular reflections. The data obtained are to be used in the development of computer optical-geometric models of space objects or their fragments (space debris) to interpret the photometry results for real space objects.

  17. Electrochemically switchable polypyrrole coated membranes

    Energy Technology Data Exchange (ETDEWEB)

    Weidlich, Claudia, E-mail: weidlich@dechema.d [DECHEMA e.V., Karl-Winnacker-Institut, Theodor-Heuss-Allee 25, D-60486 Frankfurt am Main (Germany); Mangold, Klaus-Michael [DECHEMA e.V., Karl-Winnacker-Institut, Theodor-Heuss-Allee 25, D-60486 Frankfurt am Main (Germany)

    2011-04-01

    A method for coating membranes with polypyrrole (PPy) has been developed. Different membranes, such as microfiltration as well as ion exchanger membranes have been coated with PPy to yield electrical conductivity of the membranes. The coated membranes have been investigated by cyclic voltammetry and scanning electron microscopy and their permeability and permselectivity have been tested. The results show that PPy can be tailored as cation or anion exchanger and its porosity can be controlled to avoid any impairment of the membrane by the polymer layer. These PPy coated membranes can be applied as electrochemically switchable, functionalised membranes with controllabel and variable separation properties.

  18. Studies on Nanocomposite Conducting Coatings

    Directory of Open Access Journals (Sweden)

    Amitava Bhattacharyya

    2013-01-01

    Full Text Available Nanocomposite conducting coatings can impart stable surface electrical conductivity on the substrate. In this paper, carbon nanofiber (CNF and nanographite (NG are dispersed in thermoplastic polyurethane matrix and coated on the surface of glass and polyethylene terephthalate (PET film. The nanoparticles dispersion was studied under TEM. The coating thicknesses were estimated. Further, their resistance and impedance were measured. It has been observed that the 5 wt% CNF dispersed nanocomposite coatings show good conductivity. The use of NG can bring down the amount of CNF; however, NG alone has failed to show significant improvement in conductivity. The nanocomposite coating on PET film using 2.5 wt% of both CNF and NG gives frequency-independent impedance which indicates conducting network formation by the nanoparticles. The study was carried out at different test distances on nanocomposite coated PET films to observe the linearity and continuity of the conducting network, and the result shows reasonable linearity in impedance over total test length (from 0.5 cm to 4.5 cm. The impedance of nanocomposite coatings on glass is not frequency independent and also not following linear increase path with distance. This indicates that the dispersion uniformity is not maintained in the coating solution when it was coated on glass.

  19. Coatings Technology Integration Office (CTIO)

    Data.gov (United States)

    Federal Laboratory Consortium — CTIO serves as the Air Force's central resource for aircraft coating systems and their applications. CTIO's primary objectives are pollution prevention and improved...

  20. Corrosion behavior of duplex coatings

    Directory of Open Access Journals (Sweden)

    K. Raghu Ram Mohan Reddy

    2016-07-01

    Full Text Available The titanium alloys are used in defense, aerospace, automobile, chemical plants and biomedical applications due to their very high strength and lightweight properties. However, corrosion is a life-limiting factor when Ti alloys are exposed to different chemical environments at high temperatures. In the present paper, duplex NiCrAlY/WC–Co coating is coated onto Ti6Al4V substrate to investigate the corrosion behavior of both coated samples and the substrate. The duplex coating was performed with NiCrAlY as the intermediate coat of 200 μm thickness deposited by HVOF process and WC–Co ceramic top coat with varying thicknesses of 250 μm, 350 μm and 450 μm deposited by DS process. Potentiodynamic polarization tests were employed to investigate the corrosion performance of duplex coated samples and substrate in Ringer’s solution at 37 °C and pH value was set to 5.7. Finally the results reveal that 350 μm thick coated samples showed highest corrosion resistance compared to 250 μm thick samples as well as bare substrate. However, the 450 μm thick coated sample showed poor corrosion resistance compared to the substrate. The scale formed on the samples upon corrosion was characterized by using SEM analysis to understand the degree of corrosion behavior.

  1. Protective coatings on extensible biofibres

    Science.gov (United States)

    Holten-Andersen, Niels; Fantner, Georg E.; Hohlbauch, Sophia; Waite, J. Herbert; Zok, Frank W.

    2007-09-01

    Formulating effective coatings for use in nano- and biotechnology poses considerable technical challenges. If they are to provide abrasion resistance, coatings must be hard and adhere well to the underlying substrate. High hardness, however, comes at the expense of extensibility. This property trade-off makes the design of coatings for even moderately compliant substrates problematic, because substrate deformation easily exceeds the strain limit of the coating. Although the highest strain capacity of synthetic fibre coatings is less than 10%, deformable coatings are ubiquitous in biological systems. With an eye to heeding the lessons of nature, the cuticular coatings of byssal threads from two species of marine mussels, Mytilus galloprovincialis and Perna canaliculus, have been investigated. Consistent with their function to protect collagenous fibres in the byssal-thread core, these coatings show hardness and stiffness comparable to those of engineering plastics and yet are surprisingly extensible; the tensile failure strain of P. canaliculus cuticle is about 30% and that of M. galloprovincialis is a remarkable 70%. The difference in extensibility is attributable to the presence of deformable microphase-separated granules within the cuticle of M. galloprovincialis. The results have important implications in the design of bio-inspired extensible coatings.

  2. An experimental simulation model for coated paper drying

    Directory of Open Access Journals (Sweden)

    A. Hallajisani

    2013-09-01

    Full Text Available Due to the lack of information regarding the phenomena of mass, heat, and momentum transfer in coated paper drying, substantial research work still needs to be done. A simulation model for coated paper drying is introduced which integrates heat and mass transfer mechanisms. In the model, the coated paper was assumed to have 3 layers (coated layer, wet and dry layers of the base paper, in which the thickness of each layer is a function of drying time and condition. The thickness of the wet layer of the base paper was considered to be a function of water permeability rate that in turn is a function of the moisture diffusion coefficient, time and drying rate. Movement of vapor resulting from evaporation in the middle layer was assumed to be a combination of laminar bulk flow and molecular diffusion. Radiation absorption was used as a diminishing exponential model, which depends on moisture content. Hot air and super heated vapor were used as drying fluids. Functional variables were temperature, drying fluid velocity and delay time. To verify the simulation results two compositions were applied for the coating suspension. The simulation results matched well with experimental outcomes.

  3. Transparent, Conductive Coatings Developed for Arc-Proof Solar Arrays

    Science.gov (United States)

    1996-01-01

    Transparent, conductive thin-film coatings have many potential applications where a surface must be able to dissipate electrical charges without sacrificing its optical properties. Such applications include automotive and aircraft windows, heat mirrors, optoelectronic devices, gas sensors, and solar cell array surfaces for space applications. Many spacecraft missions require that solar cell array surfaces dissipate charges in order to avoid damage such as electronic upsets, formation of pinholes in the protective coatings on solar array blankets, and contamination due to deposition of sputtered products. In tests at the NASA Lewis Research Center, mixed thin-films of sputter-deposited indium tin oxide (ITO) and magnesium fluoride (MgF2) that could be tailored to the desired sheet resistivity, showed transmittance values of greater than 90 percent. The samples evaluated were composed of mixed, thin-film ITO/MgF2 coatings, with a nominal thickness of 650 angstroms, deposited onto glass substrates. Preliminary results indicated that these coatings were durable to vacuum ultraviolet radiation and atomic oxygen. These coatings show promise for use on solar array surfaces in polar low-Earth-orbit environments, where a sheet resistivity of less than 10(exp 8)/square is required, and in geosynchronous orbit environments, where a resistivity of less than 10(exp 9)/square is required.

  4. Organic coatings degradation: Comparison between natural and artificial weathering

    Energy Technology Data Exchange (ETDEWEB)

    Deflorian, F. [Department of Materials Engineering and Industrial Technologies, University of Trento, Via Mesiano 77, Trento (Italy)], E-mail: defloria@ing.unitn.it; Rossi, S.; Fedel, M. [Department of Materials Engineering and Industrial Technologies, University of Trento, Via Mesiano 77, Trento (Italy)

    2008-08-15

    The protective properties of organic coated galvanised steel for outdoor applications are generally evaluated by means of accelerated laboratory tests, including electrochemical techniques. An open question is how these accelerated tests can be correlated with natural exposure in different environments. It is well known that many papers did not found any significant correlation between the natural exposure and laboratory tests. In this paper we propose a different approach. The starting point is the consideration to define the natural weathering by monitoring a few different environmental parameters affecting the organic coatings properties (energy from UV radiation, wet time, temperature, etc.), and not just considering the time of exposure. We studied two different galvanised materials: Zn and Zn-Al coatings, three different primers and one top coat. The samples were exposed for 12 months in three different natural environments: Trento (Italy), alpine region, Marseille (France) by the Mediterranean sea and Daytona (USA), a humid tropical environment. At the same time all the meteorological parameters were collected. The coatings weathering was evaluated in the laboratory after some different accelerated tests (salt spray chamber, UV exposure, cyclic test) and after natural exposure. A correlation between the 'natural stresses' and the 'artificial stresses' was investigated.

  5. BONDLENGTH ALTERNATION OF NANOPARTICLES Fe2O3 COATED WITH ORGANIC SURFACTANTS PROBED BY EXAFS

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The nanoparticles γ-Fe2O3 coated with surfactants.DBS,ST and CTAB.repsectively.were synthesized by microemulsion method.The coated ferric oxides.which show enhanced nonlinear optical properties compared with their bulk counterpart.were probed by EXAFS in solution forms.The x=-ray absorption spectra for Fe K edge were measured at room temperature by help of synchrotron radiation light source.Extended x-ray absorption fine structure analysis shows that the coating layers of organic molecules interact with surface atoms of nanopartices,the Fe-O bond length was extended.

  6. Polyurethane spray coating of aluminum wire bonds to prevent corrosion and suppress resonant oscillations

    CERN Document Server

    Izen, Joseph; The ATLAS collaboration; Kurth, Matthew Glenn

    2015-01-01

    Unencapsulated aluminum wedge wire bonds are common in particle-physics pixel and strip detectors. Industry-favored bulk encapsulation is eschewed due to the range of operating temperatures and radiation. Wire bond failures are a persistent, source of tracking detector failure Unencapsulated bonds are vulnerable to condensation-induced corrosion, particularly when halides are present. Oscillations from periodic Lorenz forces are documented as another source of wire bond failure. Spray application of polyurethane coatings, performance of polyurethane-coated wire bonds after climate chamber exposure, and resonant properties of PU-coated wire bonds and their resistance to periodic Lorenz forces will be described.

  7. Microplasma sprayed hydroxyapatite coatings

    CERN Document Server

    Dey, Arjun

    2015-01-01

    ""This unique book on development of microplasma sprayed HAp coating has been organized in a very compact yet comprehensive manner. This book also highlights the horizons of future research that invites the attention of global community, particularly those in bio-medical materials and bio-medical engineering field. This book will surely act as a very useful reference material for both graduate/post-graduate students and researchers in the field of biomedical, orthopedic and manufacturing engineering and research. I truly believ that this is the first ever effort which covers almost all the

  8. Mold and Crucible Coatings

    Science.gov (United States)

    1986-04-28

    34;" -"""-"’" " " ""’’ "" "" ’"" ’ j * AD I. AT)-E 9 7 W CONTRACTOR REPORT ARCCD-CR-86007 MOLD AND CRUCIBLE COATINGS Sylvia J. Canino Arthur L. Geary Nuclear...IFnlRpr April 1984_-_December 198, .. AUTNORfo) S. CONTRACT on CRAM? # "I MWef(e)I Sylvia J. Canino and Arthur L. Geary DAAK1O-84-C-0056 PERFORMING

  9. Carbonaceous film coating

    Science.gov (United States)

    Maya, Leon

    1989-01-01

    A method of making a carbonaceous film comprising heating tris(1,3,2-benzodiazaborolo)borazine or dodecahydro tris[1,3,2]diazaborine[1,2-a:1'2'-c:1"2"-e]borazine in an inert atmosphere in the presence of a substrate to a temperature at which the borazine compound decomposes, and the decomposition products deposit onto the substrate to form a thin, tenacious, highly reflective conductive coating having a narrow band gap which is susceptible of modification and a relatively low coefficient of friction.

  10. Thermal Protective Coatings

    Science.gov (United States)

    1976-03-31

    within 2 minutes for the No. 4. Sodiurn silicate was tested with alumnnunm hydroxide, nerlite, vermiculite and borax filler systems. None of the systems...1.27 cm) thick, 3/16 inch (0.48 cm) cell size, 5.5 lbs/ft 3 (88.1 kg/m 3 ) glass/phenolic honey - p comib set into the fire retardant maLerial. The sheets...COATING SPECIMEN PERCENT BY WEIGHT THICKNESS WEIGHT ANO. MATRIX FILLrR 1’fLS (CM) LBS/FT. (kg,’-), 26 50% Shell 828 Epoxy Resin Borax - 54 (.14) .39

  11. ATHENA optimized coating design

    DEFF Research Database (Denmark)

    Ferreira, Desiree Della Monica; Christensen, Finn Erland; Jakobsen, Anders Clemen

    2012-01-01

    baseline including on- and off-axis effective area curves are presented. We find that the use of linear graded multilayers can increas by 37% the integraed effective area of ATHENA in the energy range between 0.1 keV and 15keV.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE......The optimization of coating design for the ATHENA mission si described and the possibility of increasing the telescope effective area in the range between 0.1 and 10 keV is investigated. An independent computation of the on-axis effective area based on the mirror design of ATHENA is performed...

  12. USAF Inorganic Coating Successes

    Science.gov (United States)

    2012-08-01

    in2 (Marginal Fail) 7 or more pits were seen in a total of 30 in2 (Fail) Aluminum CFCC Screening Test Results Conversion Coating Alloy OC-ALC... 6061 168+ Hours 7075 168+ Hours 2024 48 Hours 5052 48-72 Hours 72-168+ Hours (5 pits on one panel at 48 hours, but then no more ) 6061 72...Dichromate Sealer Test Results Sealer Substrate Quality Thickness Corrosion Primer Dry Tape Adhesion Wet Tape Adhesion Baseline 1 Al 2024-T3 PASS

  13. Low Temperature Powder Coating

    Science.gov (United States)

    2011-02-09

    of volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) • Legacy primers contain hexavalent chrome • Conventional powder coatings...panels • Third panel exhibited a single filament extending slightly beyond allowable tolerance Filiform Corrosion Resistance LTCPC on 2024 T-3 Clad ...LTCPC on 2024 T-3 Clad O G D E N A I R L O G I S T I C S C E N T E R BE AMERICA’S BEST JTP Results • LTCPC performance similar or better than wet

  14. Compact Radiative Control Structures for Millimeter Astronomy

    Science.gov (United States)

    Brown, Ari D.; Chuss, David T.; Chervenak, James A.; Henry, Ross M.; Moseley, s. Harvey; Wollack, Edward J.

    2010-01-01

    We have designed, fabricated, and tested compact radiative control structures, including antireflection coatings and resonant absorbers, for millimeter through submillimeter wave astronomy. The antireflection coatings consist of micromachined single crystal silicon dielectric sub-wavelength honeycombs. The effective dielectric constant of the structures is set by the honeycomb cell geometry. The resonant absorbers consist of pieces of solid single crystal silicon substrate and thin phosphorus implanted regions whose sheet resistance is tailored to maximize absorption by the structure. We present an implantation model that can be used to predict the ion energy and dose required for obtaining a target implant layer sheet resistance. A neutral density filter, a hybrid of a silicon dielectric honeycomb with an implanted region, has also been fabricated with this basic approach. These radiative control structures are scalable and compatible for use large focal plane detector arrays.

  15. Remote infrared radiation detection using piezoresistive microcantilevers

    Energy Technology Data Exchange (ETDEWEB)

    Datskos, P.G.; Oden, P.I.; Thundat, T.; Wachter, E.A.; Warmack, R.J.; Hunter, S.R. [Health Sciences Research Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    1996-11-01

    A novel micromechanical infrared (IR) radiation sensor has been developed using commercially available piezoresistive microcantilevers. Microcantilevers coated with a heat absorbing layer undergo bending due to the differential stress between the top layer (coating) and the substrate. The bending causes a change in the piezoresistance and is proportional to the amount of heat absorbed. The microcantilever IR sensor exhibits two distinct thermal responses: a fast one ({lt}ms) and a slower one ({approximately}10 ms). A noise equivalent power (at a modulation frequency of 30 Hz) was estimated to be {approximately}70 nW/Hz{sup 1/2}. This value can be further reduced by designing microcantilevers with better thermal isolation that can allow microcantilevers to be used as uncooled IR radiation detectors. {copyright} {ital 1996 American Institute of Physics.}

  16. Phase-change radiative thermal diode

    CERN Document Server

    Ben-Abdallah, Philippe

    2013-01-01

    A thermal diode transports heat mainly in one preferential direction rather than in the opposite direction. This behavior is generally due to the non-linear dependence of certain physical properties with respect to the temperature. Here we introduce a radiative thermal diode which rectifies heat transport thanks to the phase transitions of materials. Rectification coefficients greater than 70% and up to 90% are shown, even for small temperature differences. This result could have important applications in the development of futur contactless thermal circuits or in the conception of radiative coatings for thermal management.

  17. Electric Dipole Antennas With Magnetic-Coated PEC Cores: Reaching the Chu Lower Bound on Q

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.

    2012-01-01

    The radiation properties of spherical electric dipole antennas with electric current excitation and material-coated perfectly electrically conducting (PEC) cores are investigated analytically using vector spherical wave functions. Closed-form expressions for electric and magnetic stored energy as...... as well as the radiation quality factor $Q$ are derived. Using these, it is shown that properly selected magnetic coating and radius of the PEC core vastly reduce the internal stored energy, and thus make the $Q$ of an electric dipole antenna approach the Chu lower bound....

  18. Dry coating, a novel coating technology for solid pharmaceutical dosage forms.

    Science.gov (United States)

    Luo, Yanfeng; Zhu, Jesse; Ma, Yingliang; Zhang, Hui

    2008-06-24

    Dry coating is a coating technology for solid pharmaceutical dosage forms derived from powder coating of metals. In this technology, powdered coating materials are directly coated onto solid dosage forms without using any solvent, and then heated and cured to form a coat. As a result, this technology can overcome such disadvantages caused by solvents in conventional liquid coating as serious air pollution, high time- and energy-consumption and expensive operation cost encountered by liquid coating. Several dry coating technologies, including plasticizer-dry-coating, electrostatic-dry-coating, heat-dry-coating and plasticizer-electrostatic-heat-dry-coating have been developed and extensively reported. This mini-review summarized the fundamental principles and coating processes of various dry coating technologies, and thoroughly analyzed their advantages and disadvantages as well as commercialization potentials.

  19. Alternative HTS coated conductors

    Science.gov (United States)

    Blaugher, R. D.; Bhattacharya, R. N.; Chen, J.; Padmanabhan, R.

    2002-10-01

    The availability of Bi-2223 high-temperature-superconductor (HTS) powder-in-tube (PIT) tape, with acceptable performance for long lengths, has provided the ability to construct a wide range of HTS electric power components. As a result, there are major worldwide projects in developing HTS electric power components for demonstration in a utility environment. Utility acceptance for superconducting power equipment will depend on several key factors: improved system performance, lower life-cycle costs, higher efficiency versus conventional technology, reliability and maintenance comparable to conventional power equipment, and a competitive installed cost. The latter is impacted by the current high cost of HTS conductors, which must be lowered to costs comparable to conventional Nb-Ti wire, i.e., $2-5/kAm. The present performance and cost of state-of-the-art Bi-2223 HTS tape, although acceptable for prototype construction, is viewed as a major deterrent that may compromise eventual commercialization for most of these electric power devices. The so-called second-generation coated conductor development, with emphasis on conductors employing HTS YBCO films, is viewed as the solution to this performance and cost issue. The potential for the Tl, Hg, and Bi-oxide superconductors for producing an HTS tape as alternatives to Bi-2223 PIT (and YBCO) will be discussed with some recent results on Bi-2212 “coated conductor” development.

  20. Space Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, William R.

    1968-01-01

    This booklet discusses three kinds of space radiation, cosmic rays, Van Allen Belts, and solar plasma. Cosmic rays are penetrating particles that we cannot see, hear or feel, which come from distant stars. Van Allen Belts, named after their discoverer are great belts of protons and electrons that the earth has captured in its magnetic trap. Solar plasma is a gaseous, electrically neutral mixture of positive and negative ions that the sun spews out from convulsed regions on its surface.