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Sample records for concentrated zirconia inks

  1. Leveling and thixotropic characteristics of concentrated zirconia inks for screen-printing

    DEFF Research Database (Denmark)

    Phair, John; Lundberg, Mats; Kaiser, Andreas

    2009-01-01

    of ethyl cellulose (binder) content upon the thixotropic and leveling characteristics of zirconia inks. While the yield stress (τ 0), extent of recovery R(%), and rate of recovery (K) increase with increasing binder content, so did the surface roughness and thickness of the screen-printed films. Increasing...... the binder content not only increases the network strength of the thick films but also leads to increased leveling time. As a result, rheological modifiers are proposed to be necessary to improve the leveling characteristics of zirconia inks without losing the green strength of the thick films......Screen-printing is a cost-effective method for the mass manufacture of zirconia-based solid oxide fuel cells (SOFCs) and oxygen separation membranes. The present work outlines an investigation into the leveling, thixotropic, and screen-printing characteristics of concentrated zirconia inks...

  2. Zirconia concentrate chlorination

    International Nuclear Information System (INIS)

    Costa, N.G.; Albuquerque Brocchi, E. de

    1990-01-01

    Chlorination experiments were conducted in order to study the kinetics of gasification of the zirconium oxide present in the zirconia concentrate. The variables studied are temperature (1173 to 1373 K), percentage of reducing agent (12 to 36%) and porosity (22 to 30%). The results indicated a greater influence of temperature and percentage of reducing agent as well as allowed the conclusion that a balance between the levels of these variables is an important factor in the appropriate chlorination conditions. (author)

  3. Synthesis of IGZO ink and study of ink-jet printed IGZO thin films with different Ga concentrations

    Science.gov (United States)

    Shen, Y. K.; Liu, Z.; Wang, X. L.; Ma, W. K.; Chen, Z. H.; Chen, T. P.; Zhang, H. Y.

    2017-12-01

    By dissolving gallium chloride (GaCl3), indium chloride (InCl3), zinc acetate dihydrate [Zn(OAc)2·2H2O] and monoethanolamine (MEA) into a solvent of 2-methoxyethanol, the IGZO ink was synthesized. Five types of IGZO ink were prepared with different molar ratios of In:Ga:Zn, which can be used for ink-jet printing process. The thermal behaviors of IGZO ink with different formulas were investigated and the ideal annealing temperature for film formation was found to be ∼450 °C. Based on the prepared ink, amorphous IGZO thin films were directly printed on the glass substrate with a FujiFilm Dimatix ink-jet printer, followed by a thermal annealing at 450 °C for 1 h. The surface morphology, crystal structure, optical transmittance, electron mobility and carrier concentration were characterized and investigated. The ink-jet printed amorphous IGZO thin films fabricated in this work can be used as switching medium in flexible resistive random access memory devices.

  4. Effect of BaTiO3 Nanopowder Concentration on Rheological Behaviour of Ceramic Inkjet Inks

    Science.gov (United States)

    Kyrpal, R.; Dulina, I.; Ragulya, A.

    2015-04-01

    The relationship between rheological properties of ceramic inkjet inks based on BaTiO3 nanopowder and solid phase concentration has been investigated. In the ink volume takes place the formation periodic colloidal structures (PCS). The determining factor of structure formation is powder-dispersant ratio. Structural constitution of in the system with the low pigment concentration represented as PCS2, that contains solid particles in deflocculated that stabilized by the presence of adsorption-solvate layers. Dilatant structure formation for such inks explained by constrained conditions of the interaction. Samples with high BaTiO3 concentration have been classified as PKS1. Dilatant properties of the PKS1 resulted in particles rearrangement under the influence of the flow. In the region of some values powder-dispersant ratio take place conversation PKS2 to PKS1 and ink structure transformation from monodisperse to aggregate state.

  5. A Limited Survey of Heavy Metal Concentrations in Fresh and Frozen Cuttlefish Ink and Mantle Used As Food.

    Science.gov (United States)

    Conficoni, Daniele; Alberghini, Leonardo; Bissacco, Elisa; Contiero, Barbara; Giaccone, Valerio

    2018-02-01

    Cuttlefish ink is consumed as a delicacy worldwide. The current study is the first assessment of heavy metal concentrations in cuttlefish ink versus mantle under different storage methods. A total of 212 samples (64 of fresh mantle, 42 of frozen mantle, 64 of fresh ink, and 42 of frozen ink) were analyzed for the detection of the following heavy metals: arsenic (As), chromium (Cr), iron (Fe), lead (Pb), mercury (Hg), and cadmium (Cd). The median As concentrations were 12.9 mg/kg for fresh mantle, 8.63 mg/kg for frozen mantle, 10.8 mg/kg for frozen ink, and 0.41 mg/kg for fresh ink. The median Cr concentrations were 0.06 mg/kg for fresh mantle and frozen ink, 0.03 mg/kg for frozen mantle, and below the limit of quantification (LOQ) for fresh ink. The median Fe concentrations were 4.08 mg/kg for frozen ink, 1.51 mg/kg for fresh mantle, 0.73 mg/kg for frozen mantle, and below the LOQ for fresh ink. The median Pb concentrations of almost all samples were below the LOQ; only two frozen ink, one fresh ink, one frozen mantle, and one fresh mantle sample exceeded the limit stipulated by the European Union. The Hg concentrations were statistically similar among the four categories of samples; the median Hg concentrations were below the LOQ, and the maximum concentrations were found in frozen ink, at 1.62 mg/kg. The median Cd concentrations were 0.69 mg/kg for frozen ink and 0.11 mg/kg for frozen mantle, fresh mantle and fresh ink concentrations were below the LOQ, and in 11.3% of the tested samples, Cd concentrations were higher than the European Union limit. The probability of samples having a Cd concentration above the legal limit was 35.75 times higher in frozen than in fresh products. Fresh ink had significantly lower concentrations of As, Cr, Fe, and Cd, but the concentrations of Hg and Pb were not significantly different from those of other products. Frozen ink had significantly higher concentrations of Cd, Cr, and Fe, but concentrations of As were lower than those in

  6. Method for calculating ionic and electronic defect concentrations in y-stabilised zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, F W [Risoe National Lab., Materials Research Dept., Roskilde (Denmark)

    1997-10-01

    A numerical (trial and error) method for calculation of concentration of ions, vacancies and ionic and electronic defects in solids (Brouwer-type diagrams) is presented. No approximations or truncations of the set of equations describing the chemistry for the various defect regions are used. Doped zirconia and doped thoria with simultaneous presence of protonic and electronic defects are taken as examples: 7 concentrations as function of oxygen partial pressure and/or water vapour partial pressure are determined. Realistic values for the equilibrium constants for equilibration with oxygen gas and water vapour, as well as for the internal equilibrium between holes and electrons were taken from the literature. The present mathematical method is versatile - it has also been employed by the author to treat more complex systems, such as perovskite structure oxides with over- and under-stoichiometry in oxygen, cation vacancies and simultaneous presence of protons. (au) 6 refs.

  7. PROCESSING OF CONCENTRATED AQUEOUS ZIRCONIA-BIOGLASS SLIPS BY SLIP CASTING

    Directory of Open Access Journals (Sweden)

    Beltina Leon

    2017-03-01

    Full Text Available 3 mol% yttria-partially stabilized zirconia (Y-TZP powder and a sol-gel derived CaO- P₂O₅- SiO₂ (64S bioglass, were used to produce Y-TZP- bioglass slip cast compacts. The rheological properties of concentrated aqueous Y-TZP- 64S suspensions prepared with two different glass contents: 10.5 vol% and 19.9 vol%, and ammonium polyacrylate (NH₄PA as dispersant, were investigated and compared with those of Y-TZP. The density of green cast samples was related to the degree of slip dispersion. The substitution of Y-TZP by 64S glass in the mixtures resulted in greater adsorption of NH₄PA; however, the viscosity and yield stress values of Y-TZP-64S slips were higher than those of Y-TZP ones for the solid loadings studied. The increase in the glass content from 10.5 to 19.9 vol% increased the viscosity and yield stress values. The presence of 64S glass in the mixtures resulted in a less dense packing of cast samples.

  8. Effect of sol concentration on the structural, morphological, optical and photoluminescence properties of zirconia thin films

    International Nuclear Information System (INIS)

    Joy, K.; Maneeshya, L.V.; Thomas, Jijimon K.; Thomas, P.V.

    2012-01-01

    ZrO 2 thin films were deposited on quartz substrates from 10 wt.%, 20 wt.% and 40 wt.% solutions of Zirconium-n-butoxide in isopropanol by sol–gel dip-coating technique. Higher concentrated sols of 20 wt.% and 40 wt.% exhibited faster gelation, where as 10 wt.% sol remained stable for two months and films synthesized from this sol remained transparent and continuous even for 12 coatings. Ellipsometric study revealed that refractive index of the films increased with increase in sol concentration which is ascribed to the decrease in porosity. X-ray diffraction study showed that a tailoring of grain size from 7.9 to 39.2 nm is possible with increase in sol concentration. Atomic force microscopy studies showed a change in growth mode from vertical to lateral mode with increase in sol concentration. The film surface revealed positive skewness and high kurtosis values which make them favorable for tribological applications. The average optical transmittance in the visible region is highest (greater than 90%) for the film deposited from 10 wt.% sol. The optical band gap decreased from 5.74 to 5.62 eV with increase in the sol concentration. Photoluminescence (PL) spectra of the films exhibit an increase in the emission intensity with increase in sol concentration which substantiates better crystalline quality of the film deposited from 40 wt.% sol and increase in oxygen vacancies. The “Red shift” of the PL spectra with increase in sol concentration originates from the increase in the grain size with sol concentration which makes it suitable for generation of solid state lighting in light emitting diode. - Highlights: ► ZrO 2 thin films were deposited on quartz substrates by sol-gel method. ► Control of grain size with sol concentration. ► Microstructure studies showed a change in growth mode from vertical to lateral mode. ► The optical band gap decreased with increase in grain size and sol concentration. ► Dependence of photoluminescence on particle size

  9. UV curable palm oil based ink

    International Nuclear Information System (INIS)

    Mek Zah Salleh; Mohd Hilmi Mahmood; Khairul Zaman Mohd Dahlan; Rosley Che Ismail

    2002-01-01

    UV curable inks are useful for their instant drying, energy saving and high productivity properties. The basic materials for formulating UV curable inks consist of prepolymer, monomers, photoinitiators, pigments and other additives. The percentage composition and ingredients depend very much on the types of inks to be produced. Palm oil is one of the main raw materials available in the country. Hence, the diversification of palm oil derivatives into new products has been given priority. The current focus of the present work is to evaluate the use of palm oil urethane acrylate (POBUA) as a prepolymer in the UV ink system. A study was conducted on the use of POBUA with other materials in ink formulation. These include the types and concentration of photoinitiators, monomers and commercial urethane acrylates. The evaluation of the ink properties such as curing, adhesion, color density have been carried out. It was found that POBUA could be introduced in the UV ink system. (Author)

  10. UV curable palm oil based inks

    International Nuclear Information System (INIS)

    Mek Zah Salleh; Hilmi Mahmood

    2002-01-01

    UV curable inks are useful for their instant drying, energy saving and high productivity properties. The basic materials for formulating UV curable inks consist of prepolymer, monomers, photoinitiators, pigments and other additives. The percentage composition and ingredients depend very much on the types of inks to be produced. Palm oil is one of the main raw materials available in the country. Hence, the diversification of palm oil derivatives into new products has been given priority. The current focus of the present work is to evaluate the use of palm oil based urethane acrylate (POBUA) as a prepolymer in the UV inks system. A study was conducted on the use of POBUA with other materials in ink formulation. These include the types and concentration of photoinitiators, monomers and commercial urethane acrylates. The evaluation of the ink properties such as curing, adhesion, color density have been carried out. It was found that POBUA could be introduced in the UV ink system. (Author)

  11. Effect of binder concentration and blade gap on Yttria stabilized Zirconia tapes obtained by tape casting

    Energy Technology Data Exchange (ETDEWEB)

    Mena Garcia, J.; Reyes Rojas, A.; Rodriguez Gonzalez, C.A.; Hernandez Paz, J.; Garcia Casillas, P.E.; Enriquez Carrejo, J.L.; Camacho Montes, H.

    2016-07-01

    The tape casting method has kept its interest over the years due to the wide spectrum of its applications and its economic viability in comparison to other techniques focused on micrometric thin films. Two key parameters for tape casting are the binder relative amount and the Dr. Blade gap. The binder relative amount has a strong influence on the rheological properties for the ceramic YSZ slurry (ethanol, butanone, TEA, PVB, PEG, DEP). The coefficient K and the exponent m of the Cross model are reported to be inside the ranges 152.25-231.12 and 0.00987-0.26646 for PVB binder weight percentage concentrations between 6% and 12%. It is possible to describe the ceramic tape thickness dependence by means of a linear relation depending on the Dr. Blade gap whose linear coefficients (slope) are equal to 0.0350 and 0.2171 for green and sintered tapes respectively, with the YSZ slurry of the present work. (Author)

  12. Trace element ink spiking for signature authentication

    International Nuclear Information System (INIS)

    Hatzistavros, V.S.; Kallithrakas-Kontos, N.G.

    2008-01-01

    Signature authentication is a critical question in forensic document examination. Last years the evolution of personal computers made signature copying a quite easy task, so the development of new ways for signature authentication is crucial. In the present work a commercial ink was spiked with many trace elements in various concentrations. Inorganic and organometallic ink soluble compounds were used as spiking agents, whilst ink retained its initial properties. The spiked inks were used for paper writing and the documents were analyzed by a non destructive method, the energy dispersive X-ray fluorescence. The thin target model was proved right for quantitative analysis and a very good linear relationship of the intensity (X-ray signal) against concentration was estimated for all used elements. Intensity ratios between different elements in the same ink gave very stable results, independent on the writing alterations. The impact of time both to written document and prepared inks was also investigated. (author)

  13. The Effect of Zirconia in Hydroxyapatite on Staphylococcus epidermidis Growth

    Directory of Open Access Journals (Sweden)

    Widowati Siswomihardjo

    2012-01-01

    . Conclusion. The addition of zirconia into hydroxyapatite affected the growth of S. epidermidis. Hydroxyapatite with 20% zirconia proved to be an effective concentration to inhibit the growth of S. epidermidis colony.

  14. The development of substitute inks and controls for reducing workplace concentrations of organic solvent vapors in a vinyl shower curtain printing plant.

    Science.gov (United States)

    Piltingsrud, Harley V; Zimmer, Anthony T; Rourke, Aaron B

    2003-08-01

    During the summer of 1994, football players at a practice field reported noxious odors in the area. Ohio Environmental Protection Agency (OEPA) investigations of industries surrounding the field included a printing facility producing vinyl shower curtains with screen-printed designs. Though not the source of the odor, they were discharging volatile organic compounds directly to the environs in violation of OEPA regulations. To achieve compliance they installed a catalytic oxidizer for treating discharged air. Due to high equipment costs, the capacity of the installed catalytic oxidizer resulted in a substantial reduction in discharged air flow rates and increased solvent vapor concentrations within the workplace. Vapor levels caused worker discomfort, prompting a request for assistance from the Ohio Bureau of Workers Compensation. The vapor concentrations were found to exceed NIOSH, OSHA, and ACGIH acceptable exposure levels. The workers were then required to wear organic vapor removing respirators full-time while printing as a temporary protective measure. The company requested NIOSH assistance in finding methods to reduce solvent vapor concentrations. NIOSH studies included the identification of the sources and relative magnitude of solvent emissions from the printing process, the design of controls for the emissions, and the development of substitute inks using non-photochemically reactive solvents. The new ink system and controls allowed OEPA removal of the requirement for the treatment of discharged air and substantial increases in dilution ventilation. Increased ventilation would permit reduction in worker exposures to less than 1/3 mixture TLV levels and removal of requirements for respirator usage. This solution was the result of a comprehensive review of all facets of the problem, including OEPA regulations. It also required cooperative work between the company and federal, state, and local governmental agencies.

  15. Optimization of Graphene Conductive Ink with 73 wt% Graphene Contents.

    Science.gov (United States)

    Xu, Chang-Yan; Shi, Xiao-Mei; Guo, Lu; Wang, Xi; Wang, Xin-Yi; Li, Jian-Yu

    2018-06-01

    With the pace of development accelerating in printed electronics, the fabrication and application of conductive ink have been brought into sharp focus in recent years. The discovery of graphene also unfolded a vigorous research campaign. In this paper, we prepared graphene conductive ink and explored the feasibility of applying the ink to flexible paper-based circuit. Since experimental study concentrating upon ink formulation was insufficient, orthogonal test design was used in the optimization of preparation formula of conductive ink for the first time. The purpose of this study was to determine the effect of constituent dosage on conductivity of graphene conductive ink, so as to obtain the optimized formula and prepare graphene conductive ink with good conductivity. Characterization of optimized graphene conductive ink we fabricated showed good adhesion to substrate and good resistance to acid and water. The graphene concentration of the optimized ink reached 73.17 wt% solid content. Particle size distribution of graphene conductive ink was uniform, which was about 1940 nm. Static surface tension was 28.9 mN/m and equilibrium contact angle was 23°, demonstrating that conductive ink had good wettability. Scanning Electron Microscope (SEM) analysis was also investigated, moreover, the feasibility of lightening a light-emitting diode (LED) light was verified. The graphene conductive ink with optimized formula can be stored for almost eight months, which had potential applications in flexible paper-based circuit in the future.

  16. Radiation curable inks

    International Nuclear Information System (INIS)

    Bolon, D.A.; Lucas, G.M.

    1976-01-01

    A radiation curable ink is provided which is convertible to a conductive coating when cured on the surface of a substrate. When used as a printing ink, improved results are achieved if a minor amount of a blend of paraffin waxes is employed to control solvent evaporation

  17. STABILISED ZIRCONIA

    Directory of Open Access Journals (Sweden)

    LUZ STELLA ARIAS-MAYA

    2014-01-01

    Full Text Available La densificación y la contracción de cerámicos u otros materiales en polvo pueden ser predichos de una manera sencilla usando la curva maestra de sinterizado. En este trabajo se han obtenido los datos de densificación requeridos para construir la curva maestra de sinterizado de zirconia en polvo estabilizada con 3-mol% itria. Se sinterizaron muestras compactadas en frío, así como películas gruesas hechas del mismo polvo y aplicadas a un sustrato rígido. Las pruebas de sinterizado libre y con restricción fueron realizadas aplicando tres velocidades de calentamiento, incluyendo o no una etapa isotérmica a la máxima temperatura de ~1450 °C. La contracción de las muestras se midió durante la densificación usando un dilatómetro de varilla de presión. También se usó un horno convencional, aplicando la misma curva de calentamiento para comparar resultados. El análisis microestructural fue logrado mediante microscopía de barrido electrónico, microscopía de barrido electrónico ambiental y microscopía óptica. Se obtuvo una concordancia aceptable entre muestras similares sinterizadas en el dilatómetro y en el horno convencional, indicando que los datos del dilatómetro pueden ser usados para ambos ambientes. Las muestras que se sinterizaron sin restricción alcanzaron menores densidades que las películas, probablemente debido a que sus densidades iniciales eran menores. Para las muestras libres de restricción, se obtuvo una curva maestra de sinterizado con una energía de activación de 550 kJ mol-1. Para las películas sinterizadas con restricción, algunos problemas asociados con el sustrato y con las incertidumbres de las mediciones impidieron la caracterización de la película, es decir, la obtención de una curva maestra de sinterizado con un solo valor de energía de activación.

  18. Electric treatment for hydrophilic ink deinking.

    Science.gov (United States)

    Du, Xiaotang; Hsieh, Jeffery S

    2017-09-01

    Hydrophilic inks have been widely used due to higher printing speed, competitive cost and being healthy non-organic solvents. However, they cause problems in both product quality and process runnability due to their hydrophilic surface wettability, strong negative surface charge and sub-micron size. Electric treatment was shown to be able to increase the ink sizes from 60 nm to 700 nm through electrocoagulation and electrophoresis. In addition, electric treatment assisted flotation could reduce effective residual ink concentration (ERIC) by 90 ppm, compared with only 20 ppm by traditional flotation. Furthermore, the effect of electric treatment alone on ink separation was investigated by two anode materials, graphite and stainless steel. Both of them could remove hydrophilic inks with less than 1% yield loss via electroflotation and electrophoresis. But graphite is a better material as the anode because graphite reduced ERIC by an additional 100 ppm. The yield loss of flotation following electric treatment was also lower by 17% if graphite was the anode material. The difference between the two electrode materials resulted from electrocoagulation and ink redeposition during electric treatment. An electric pretreatment-flotation-hyperwashing process was conducted to understand the deinking performance in conditions similar to a paper mill, and the ERIC was reduced from 950 ppm to less than 400 ppm.

  19. Zirconia nano-colloids transfer from continuous hydrothermal synthesis to inkjet printing

    DEFF Research Database (Denmark)

    Rosa, Massimo; Gooden, P. N.; Butterworth, S.

    2017-01-01

    Water dispersions of nanometric yttria stabilized zirconia (YSZ) particles synthesized by Continuous Hydrothermal Synthesis are transferred into nano-inks for thin film deposition. YSZ nanoparticles are synthesized in supercritical conditions resulting in highly dispersed crystals of 10 nm in size...

  20. Zirconia in biomedical applications.

    Science.gov (United States)

    Chen, Yen-Wei; Moussi, Joelle; Drury, Jeanie L; Wataha, John C

    2016-10-01

    The use of zirconia in medicine and dentistry has rapidly expanded over the past decade, driven by its advantageous physical, biological, esthetic, and corrosion properties. Zirconia orthopedic hip replacements have shown superior wear-resistance over other systems; however, risk of catastrophic fracture remains a concern. In dentistry, zirconia has been widely adopted for endosseous implants, implant abutments, and all-ceramic crowns. Because of an increasing demand for esthetically pleasing dental restorations, zirconia-based ceramic restorations have become one of the dominant restorative choices. Areas covered: This review provides an updated overview of the applications of zirconia in medicine and dentistry with a focus on dental applications. The MEDLINE electronic database (via PubMed) was searched, and relevant original and review articles from 2010 to 2016 were included. Expert commentary: Recent data suggest that zirconia performs favorably in both orthopedic and dental applications, but quality long-term clinical data remain scarce. Concerns about the effects of wear, crystalline degradation, crack propagation, and catastrophic fracture are still debated. The future of zirconia in biomedical applications will depend on the generation of these data to resolve concerns.

  1. The Ink of Citizenship

    Science.gov (United States)

    Patel, Leigh

    2017-01-01

    Nations actively write themselves onto human bodies. They etch and scratch their borders onto human flesh with figurative, often contradictory, ink that delivers stark material impact. The impacts hold their greatest force in metering the hinged consequences of contingent citizenship for some and unfettered citizenship for a few others. In this…

  2. Electrical characterization of zirconia-niobium and zirconia-titanium composites; Caracterizacao eletrica dos compositos zirconia-niobio e zirconia-titanio

    Energy Technology Data Exchange (ETDEWEB)

    Reis, S.T. dos

    1994-12-31

    Zirconia-niobium and zirconia-titanium composites were made by powder mixing, cold pressing, and vacuum sintering at 1600{sup 0} C. The metallic particles were added in the proportion of 0-50% by volume. Electrical resistivity measurements were performed by the two probes and the four probes d.c. method as a function of metallic particle concentration. Electrical resistivity of these composites decreased sharply in the region of 30-40 vol% Nb or Ti, in agreement with the percolation theory. Tests in an induction furnace were performed to check the self-heating response of these composites. (author). 33 refs, 40 figs, 11 tabs.

  3. Zirconia - the cinderella transformation

    International Nuclear Information System (INIS)

    Hannink, R.H.J.

    1999-01-01

    Zirconia and its alloys have formed a turning point in mechanical property developments of engineering ceramics. This can be stated primarily because zirconia alloys were one of the first ceramic systems in which it was demonstrated that the mechanical properties could be tailored using careful control of composition, powder processing and thermal treatment. For the improved mechanical properties to be captured in zirconia-based or containing ceramics, control of the tetragonal to monoclinic transformation is required. Through microstructural control, zirconia-based ceramics can be tailored to form some of the strongest and toughest ceramics yet developed. By carefully controlling the use of various dopants (alloying additions), a variety of microstructures can be produced all of which may exhibit transformation toughening. While success in capturing the benefits of transformation toughening relies on adequate powder processing techniques, this review is restricted to outlining the phase control and behaviour that make zirconia and its alloys such a scientifically fascinating and rewarding system for study and a commercially appealing ceramic material

  4. Durability of ink jet prints

    International Nuclear Information System (INIS)

    Dobric, E; Mirkovic, I Bolanca; Bolanca, Z

    2010-01-01

    The aim of this paper is the result presentation of some optical properties research for ink jet prints after: exposing the prints to the mixed daylight and artificial light, exposing of prints to the sun-light through the glass window, and exposing of prints to outdoor conditions during the summer months. The prints obtained by piezoelectric and thermal ink jet technologies were used in the researches. The dye-based inks and the pigmented inks based on water and the low solvent inks were used. The results of these researches, except the scientific contribution in the domain of understanding and explaining the environmental conditions on the gamut size, i.e. the range of color tonality, colorimetric stability and print quality, can be used by the ink and paper manufacturers in new formulations, offer data for the printer producers for further production and evaluation of the position of their products.

  5. One-Bath Pretreatment for Enhanced Color Yield of Ink-Jet Prints Using Reactive Inks

    Directory of Open Access Journals (Sweden)

    Wei Ma

    2017-11-01

    Full Text Available In order to facilely increase the color yield of ink-jet prints using reactive inks, one-bath pretreatment of cotton fabrics with pretreatment formulation containing sodium alginate, glycidyltrimethylammonium chloride (GTA, sodium hydroxide, and urea is designed for realizing sizing and cationization at the same time. The pretreatment conditions, including the concentrations of GTA and alkali, baking temperature, and time are optimized based on the result of thecolor yield on cationic cotton for magenta ink. The mechanism for color yield enhancement on GTA-modified fabrics is discussed and the stability of GTA in the print paste is investigated. Scanning electron microscopey, tear strength, and thermogravimetric analysis of the modified and unmodified cotton are studied and compared. Using the optimal pretreatment conditions, color yield on the cationic cotton for magenta, cyan, yellow, and black reactive inks are increased by 128.7%, 142.5%, 71.0%, and 38.1%, respectively, compared with the corresponding color yield on the uncationized cotton. Much less wastewater is produced using this one-bath pretreatment method. Colorfastness of the reactive dyes on the modified and unmodified cotton is compared and boundary clarity between different colors is evaluated by ink-jet printing of colorful patterns.

  6. Zirconia UV-curable colloids for additive manufacturing via hybrid inkjet printing-stereolithography

    DEFF Research Database (Denmark)

    Rosa, Massimo; Barou, C.; Esposito, Vincenzo

    2018-01-01

    Currently, additive manufacturing of ceramics by stereolithography (SLA) is limited to single materials and by a poor thickness resolution that strongly depends on the ceramic particles-UV light interaction. Combining selective laser curing with inkjet printing represents a novel strategy...... to overcome these constrains. Nonetheless, this approach requires UV-curable inks that allow hardening of the printed material and sintering to high density. In this work, we report how to design an ink for inkjet printing of yttria stabilized zirconia (YSZ) which can be impressed by addition of UV...

  7. Preliminary researches regarding edible jet printing inks

    International Nuclear Information System (INIS)

    Nemtanu, M. R.; Brasoveanu, M.

    2002-01-01

    The automatic reproduction of images with edible materials is a new method used lately to decorate cakes. An important component of this technology is the ink. The paper presents the results obtained by using different physical methods for analysis of some jet printing inks types. The analysed inks were the Canon inks and edible inks from Thailand. The main considered methods were the spectrocolourymetrical, rheological, electrochemical. Choosing as a chromatic standard the Canon inks and for the physicochemical properties the edible inks from Thailand, it was prepared a yellow edible printing ink which was characterized by same methods

  8. Electrical characterization of zirconia-niobium and zirconia-titanium composites

    International Nuclear Information System (INIS)

    Reis, S.T. dos.

    1993-01-01

    Zirconia-niobium and zirconia-titanium composites were made by powder mixing, cold pressing, and vacuum sintering at 1600 0 C. The metallic particles were added in the proportion of 0-50% by volume. Electrical resistivity measurements were performed by the two probes and the four probes d.c. method as a function of metallic particle concentration. Electrical resistivity of these composites decreased sharply in the region of 30-40 vol% Nb or Ti, in agreement with the percolation theory. Tests in an induction furnace were performed to check the self-heating response of these composites. (author). 33 refs, 40 figs, 11 tabs

  9. Yield stress of alumina-zirconia suspensions

    International Nuclear Information System (INIS)

    Ramakrishnan, V.; Pradip; Malghan, S.G.

    1996-01-01

    The yield stress of concentrated suspensions of alumina, zirconia, and mixed alumina-zirconia powders was measured by the vane technique as a function of solids loading, relative amounts of alumina and zirconia, and pH. At the isoelectric point (IEP), the yield stress varied as the fourth power of the solids loading. The relative ratio of alumina and zirconia particles was important in determining the yield stress of the suspension at the IEP. The yield stress of single and mixed suspensions showed a marked variation with pH. The maximum value occurred at or near the IEP of the suspension. The effect of electrical double-layer forces on the yield stress can be described on the basis of the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. A normalized yield stress--that is, the ratio of the yield stress at a given pH to the yield stress at the IEP predicted by this model--showed good correlation with experimental data

  10. Eco friendly nitration of toluene using modified zirconia

    Directory of Open Access Journals (Sweden)

    K.R. Sunaja Devi

    2013-03-01

    Full Text Available Nitration of toluene has been studied in the liquid phase over a series of modified zirconia catalysts.  Zirconia, zirconia- ceria (Zr0.98Ce0.02O2, sulfated zirconia and sulfated zirconia- ceria were synthesised by co precipitation method and were characterised by X-ray diffraction, BET surface area, Infra red spectroscopy analysis (FTIR, Thermogravimetric analysis (TGA, Scanning Electron Microscopy (SEM and Energy Dispersive X ray analysis (EDAX. The acidity of the prepared catalysts was determined by FTIR pyridine adsorption study. X-ray diffraction studies reveal that the catalysts prepared mainly consist of tetragonal phase with the crystallite size in the nano range and the tetragonal phase of zirconia is stabilized by the addition of ceria. The modified zirconia samples have higher surface area and exhibits uniform pore size distribution aggregated by zirconia nanoparticles. The onset of sulfate decomposition was observed around 723 K for sulfated samples. The catalytic performance was determined for the liquid phase nitration of toluene to ortho-, meta- and para- nitro toluene. The effect of reaction temperature, concentration of nitric acid, catalyst reusability and reaction time was also investigated. © 2013 BCREC UNDIP. All rights reservedReceived: 20th November 2012; Revised: 8th December 2012; Accepted: 7th January 2013[How to Cite: K. R. S. Devi, S. Jayashree, (2013. Eco friendly nitration of toluene using modified zirconia. Bulletin of Chemical Reaction Engineering & Catalysis, 7 (3: 205-214. (doi:10.9767/bcrec.7.3.4154.205-214][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.7.3.4154.205-214 ] View in  |

  11. Antibacterial Activity of Melanin from Cuttlefish and Squid Ink

    Directory of Open Access Journals (Sweden)

    Yuspihana Fitrial

    2017-08-01

    Full Text Available Marine environment comprises of many organism which are known to posses bioactive compound as a common means of self-defense or for the protection of eggs and embryos. Class Cephalopods (such as squidand cuttlefish are notable for their defences, such as jetting escape movements, changes in colouration, toxic venom and inking.This study aims to compare the antibacterial activity of melanin from cuttlefish ink (Sepia sp. with squid ink (Loligo sp. against E. coli. Extraction and purification studies were carried out on Sepia and Loligo melanin using a hydrochloric acid 0,5M treatment under mechanical.The melanins were obtained and further evaluated their activity by direct contact methods between melanin and E. coli in nutrient broth.Total microbes was counted by total plate count.Both inks also was tested their activity against E. coli. The results showed that melanin from cuttlefish and squid inks had inhibitory activity at concentrations of 10 mg / ml and 20 mg / mL, respectively reaching 99.99% against E. coli.The inks of both Cephalopods at the same concentration as melanin, did not show any inhibitory activity against E. coli.  The melanin of Sepia sp. have a higher antibacterial activity than the melanin of Loligo sp.

  12. Fabrication and sulfurization of Cu{sub 2}SnS{sub 3} thin films with tuning the concentration of Cu-Sn-S precursor ink

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chi-Jie [Institute of Microelectronics & Department of Electrical Engineering, National Cheng Kung University, Taiwan (China); Shei, Shih-Chang, E-mail: scshei@mail.nutn.edu.tw [Department of Electrical Engineering, Nation University of Tainan, Taiwan (China); Chang, Shih-Chang [Department of Electrical Engineering, Nation University of Tainan, Taiwan (China); Chang, Shoou-Jinn [Institute of Microelectronics & Department of Electrical Engineering, National Cheng Kung University, Taiwan (China)

    2016-12-01

    Highlights: • Tuning the relative reaction rate of component phases proved to be beneficial in controlling the reaction process. • Low-concentration samples display closely packed Cu{sub 2}SnS{sub 3} grains with a flat morphology. • Optical band-gap energy measured at 1.346 eV suitable for thin-film solar cell applications. - Abstract: In this study, Cu-Sn-S nanoinks were synthesized by combining chelating polyetheramine to Cu, Sn, S powders of various concentrations. X-ray diffraction patterns indicate that nanoinks synthesized at low concentrations are composed almost entirely of binary phases SnS and Cu{sub 2}S. Synthesizing nanoinks at higher concentrations decreased the quantity of binary phase and led to the appearance of ternary phase Cu{sub 4}SnS{sub 4}. Following sulfurization, single phase Cu{sub 2}SnS{sub 3} (CTS) thin film was obtained from nanoinks of low concentration; however, impurities, such as Cu{sub 2}S were detected in the thin film obtained from nanoinks of high concentration. This can be attributed to the fact that lower concentrations reduce the reactivity of all the elements. As a result, the SnS phase reacted more readily and more rapidly, resulting in the early formation of a stoichiometric CTS thin film during sulfurization. Under these reaction conditions, Cu{sub 2}S and SnS transform into CTS and thereby prevent the formation of unwanted phases of Cu{sub 2}S and Cu{sub 4}SnS{sub 4}. Raman spectra revealed that second phase Cu{sub 2}S phase remained in the high-concentration samples, due to an increase in reactivity due to the participation of a greater proportion of the copper in the reaction. The surface microstructure of low-concentration samples display closely packed Cu{sub 2}SnS{sub 3} grains with a flat morphology and an atomic composition ratio of Cu:Sn:S = 34.69:15.90:49.41, which is close to stoichiometric. Hall measurement revealed that low-concentration sample has superior electrical properties; i.e., a hole

  13. Phase characterization of precipitated zirconia

    International Nuclear Information System (INIS)

    Gutzov, S.; Ponahlo, J.; Lengauer, C.L.; Beran, A.

    1994-01-01

    The phase compositions of undoped and europium-doped zirconia samples, obtained by precipitation and thermal treatment from 350 to 1,000 C, have been investigated by powder X-ray diffractometry, infrared spectroscopy, and cathodoluminescence spectroscopy. The low-temperature stabilization of tetragonal zirconia is mainly controlled by the presence of anion additives, such as ammonium chloride. The influences of the crystallite size is less important. Cathodoluminescence spectra show a structural similarity between tetragonal and amorphous zirconia

  14. Surface treatment of zirconia ceramics

    International Nuclear Information System (INIS)

    1980-01-01

    A method of chemically micropitting and/or microcratering at least a portion of a smooth surface of an impervious zirconia-base ceramic is described, comprising (a) contacting the smooth surface with a liquid leachant selected from concentrated sulphuric acid, ammonium bisulphate, alkali metal bisulphates and mixtures thereof at a temperature of at least 250 0 C for a period of time sufficient to effect micropitting and/or microcratering generally uniformly distributed throughout the microstructure of the resultant leached surface; (b) removing the leached surface from contact with the leachant; (c) contacting the leached surface with hydrochloric acid to effect removal from the leached surface of a residue thereon comprising sulphate of metal elements including zirconium in the ceramic; (d) removing the leached surface from contact with the hydrochloric acid; and (e) rinsing the leached surface with water to effect removal of acid residue from that surface. (author)

  15. Ink composition for making a conductive silver structure

    Science.gov (United States)

    Walker, Steven B.; Lewis, Jennifer A.

    2016-10-18

    An ink composition for making a conductive silver structure comprises a silver salt and a complex of (a) a complexing agent and a short chain carboxylic acid or (b) a complexing agent and a salt of a short chain carboxylic acid, according to one embodiment. A method for making a silver structure entails combining a silver salt and a complexing agent, and then adding a short chain carboxylic acid or a salt of the short chain carboxylic acid to the combined silver salt and a complexing agent to form an ink composition. A concentration of the complexing agent in the ink composition is reduced to form a concentrated formulation, and the silver salt is reduced to form a conductive silver structure, where the concentrated formulation and the conductive silver structure are formed at a temperature of about 120.degree. C. or less.

  16. On quantification of residual ink content and deinking efficiency in recycling of mixed office waste paper

    Science.gov (United States)

    Bo Li; Gaosheng Wang; Kefu Chen; David W. Vahey; Junyong Zhu

    2011-01-01

    Although (flotation) deinking has been a common industry practice for several decades, true residual ink content and deinking efficiency have never been quantified. Paper brightness and ERIC (Effective Residual Ink Concentration), based on measurements of the absorption coefficient of deinked pulp, have been used to determine performance of flotation deinking processes...

  17. Effect of Mg2+ and Fe2+ Concentrations in Culture Medium on CGF Formation from Microalgae Chlorella Pyrenoidosa Ink and Analysis of Amino Acids by Liquid Chromatography-Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Kusmiati Kusmiati

    2015-06-01

    Full Text Available Chlorella pyrenoidosa (C. pyrenoidosa contains Chlorella Growth Factor (CGF, which consists of proteins and polysaccharides. CGF is located inside the nucleus of cells and is beneficial to humans as a food supplement, an immunity booster, and an antioxidant. CGF formation of C. pyrenoidosa is influenced by medium composition. C. pyrenoidosa INK was cultured in a modified basal medium (MBM with various concentrations of Mg2+ (0.5, 1.0, and 1.5 g/L and Fe2+ (3.5×10-4 and 5.0×10-4 g/L. The experiments were performed and analyzed under a completely randomized design using a 2-L bottle with three replications. The results showed that MBM with 1.0 g/L of Mg2+ and 3.5×10-4 g/L of Fe2+ yielded the optimal growth curve for C. pyrenoidosa. Analysis of protein content was carried out using the Lowry method with a spectrophotometer at λ=750 nm, and the obtained results were 0.0974 mg/mL (extract and 6.4097 mg/ml (supernatant. Furthermore, analysis of glucose content was carried out using the phenol sulfate method (λ = 490 nm, and the obtained results were 49.331 ppm (extract and 1566.911 ppm (supernatant. Analysis of amino acids in CGF using liquid chromatography-mass spectrometry (LC-MS indicated the presence of tyrosine, proline, glutamate, alanine, valine, tryptopan, phenylalanine, methionine, and leucine-isoleucine.

  18. Zirconia based ceramics

    International Nuclear Information System (INIS)

    Bressiani, J.C.; Bressiani, A.H.A.

    1989-05-01

    Within the new generation of ceramic materials, zirconia continues to attract ever increasing attention of scients, technologists and users by virtue of its singular combination of properties and being able to perform thermo-mechanical, electroeletronic, chemico-biological functions. Nevertheless, in order to obtain these properties, a through understanding of the phase transformation mechanisms and microstructural changes is necessary. This paper discusses the main parameters that require control during fabrication of these materials to obtain desired properties for a specific application. (author) [pt

  19. Raman spectroscopy and capillary electrophoresis applied to forensic colour inkjet printer inks analysis.

    Science.gov (United States)

    Król, Małgorzata; Karoly, Agnes; Kościelniak, Paweł

    2014-09-01

    Forensic laboratories are increasingly engaged in the examination of fraudulent documents, and what is important, in many cases these are inkjet-printed documents. That is why systematic approaches to inkjet printer inks comparison and identification have been carried out by both non-destructive and destructive methods. In this study, micro-Raman spectroscopy and capillary electrophoresis (CE) were applied to the analysis of colour inkjet printer inks. Micro-Raman spectroscopy was used to study the chemical composition of colour inks in situ on a paper surface. It helps to characterize and differentiate inkjet inks, and can be used to create a spectra database of inks taken from different cartridge brands and cartridge numbers. Capillary electrophoresis in micellar electrophoretic capillary chromatography mode was applied to separate colour and colourless components of inks, enabling group identification of those components which occur in a sufficient concentration (giving intensive peaks). Finally, on the basis of the obtained results, differentiation of the analysed inks was performed. Twenty-three samples of inkjet printer inks were examined and the discriminating power (DP) values for both presented methods were established in the routine work of experts during the result interpretation step. DP was found to be 94.0% (Raman) and 95.6% (CE) when all the analysed ink samples were taken into account, and it was 96.7% (Raman) and 98.4% (CE), when only cartridges with different index numbers were considered. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. Hydrothermal crystallization of zirconia and zirconia solid solutions

    International Nuclear Information System (INIS)

    Pyda, W.; Haberko, K.; Bucko, M.M.

    1991-01-01

    Zirconia as well as yttria-zirconia and calcia-zirconia solid-solution powders were crystallized under hydrothermal conditions from (co)precipitated hydroxides. The morphology of the power particles is strongly dependent on the crystallization conditions. The powders crystallized in a water solution of Na, K, and Li hydroxides show elongated particles of much larger sizes than those which result from the process carried out in pure water or a water solution of Na, K, or Li chlorides. The shapes of the latter particles are isometric. In this paper the growth mechanism of the elongated particles is suggested

  1. Reductive photocatalysis and smart inks.

    Science.gov (United States)

    Mills, Andrew; Wells, Nathan

    2015-05-21

    Semiconductor-sensitised photocatalysis is a well-established and growing area of research, innovation and commercialisation; the latter being mostly limited to the use of TiO2 as the semiconductor. Most of the work on semiconductor photocatalytic systems uses oxygen as the electron acceptor and explores a wide range of electron donors; such systems can be considered to be examples of oxidative photocatalysis, OP. OP underpins most current examples of commercial self-cleaning materials, such as: glass, tiles, concrete, paint and fabrics. OP, and its myriad of applications, have been reviewed extensively over the years both in this journal and elsewhere. However, the ability of TiO2, and other semiconductor sensitisers, to promote reductive photocatalysis, RP, especially of dyes, is significant and, although less well-known, is of growing importance. In such systems, the source of the electrons is some easily oxidised species, such as glycerol. One recent, significant example of a RP process is with respect to photocatalyst activity indicator inks. paiis, which provide a measure of the activity of a photocatalytic film under test via the rate of change of colour of the dye in the ink coating due to irreversible RP. In contrast, by incorporating the semiconductor sensitiser in the ink, rather than outside it, it is possible to create an effective UV dosimeter, based on RP, which can be used as a sun-burn warning indicator. In the above examples the dye is reduced irreversibly, but when the photocatalyst in an ink is used to reversibly photoreduce a dye, a novel, colourimetric oxygen-sensitive indicator ink can be created, which has commercial potential in the food packaging industry. Finally, if no dye is present in the ink, and the semiconductor photocatalyst-loaded ink film coats an easily reduced substrate, such as a metal oxide film, then it can be used to reduce the latter and so, for example, clean up tarnished steel. The above are examples of smart inks, i

  2. Application of cellulose nanofibers to remove water-based flexographic inks from wastewaters.

    Science.gov (United States)

    Balea, Ana; Monte, M Concepción; de la Fuente, Elena; Negro, Carlos; Blanco, Ángeles

    2017-02-01

    Water-based or flexographic inks in paper and plastic industries are more environmentally favourable than organic solvent-based inks. However, their use also creates new challenges because they remain dissolved in water and alter the recycling process. Conventional deinking technologies such as flotation processes do not effectively remove them. Adsorption, coagulation/flocculation, biological and membrane processes are either expensive or have negative health impacts, making the development of alternative methods necessary. Cellulose nanofibers (CNF) are biodegradable, and their structural and mechanical properties are useful for wastewater treatment. TEMPO-oxidised CNF have been evaluated for the decolourisation of wastewaters that contained copper phthalocyanine blue, carbon black and diarlyide yellow pigments. CNF in combination with a cationic polyacrylamide (cPAM) has also been tested. Jar-test methodology was used to evaluate the efficiency of the different treatments and cationic/anionic demand, turbidity and ink concentration in waters were measured. Results show that dual-component system for ink removal has a high potential as an alternative bio-based adsorbent for the removal of water-based inks. In addition, experiments varying CNF and cPAM concentrations were performed to optimise the ink-removal process. Ink concentration reductions of 100%, 87.5% and 83.3% were achieved for copper phthalocyanine blue, carbon black and diarlyide yellow pigments, respectively. Flocculation studies carried out show the decolourisation mechanism during the dual-component treatment of wastewaters containing water-based inks.

  3. Think Before You Ink: Are Tattoos Safe?

    Science.gov (United States)

    ... Consumers Consumer Updates Think Before You Ink: Are Tattoos Safe? Share Tweet Linkedin Pin it More sharing ... I be concerned about unsafe practices, or the tattoo ink itself? Both. While you can get serious ...

  4. Theoretical studies of zirconia and defects in zirconia. Final report

    International Nuclear Information System (INIS)

    Jansen, H.J.F.

    1995-01-01

    Supported by this grant the author has performed total energy electronic structure calculations for cubic, tetragonal, and monoclinic zirconia. The results of these calculations agree with the observed ordering of structures in the phase diagram. He has developed model potentials based on the total energy results. Molecular dynamics calculations using these model potentials give a good description of the phase transitions in and the thermal properties of zirconia

  5. Catalytic microcontact printing without ink

    NARCIS (Netherlands)

    Li, X.; Péter, M.; Huskens, Jurriaan; Reinhoudt, David

    2003-01-01

    A novel microcontact printing technique is described that does not require ink. Patterns were created by direct contact of oxidized PDMS stamps with silyl ether-derivatized, acid-labile SAMs on gold. The surface of the stamps was oxidized by oxygen plasma to give a layer of silicon oxide. These

  6. Bioanalytical evidence that chemicals in tattoo ink can induce adaptive stress responses.

    Science.gov (United States)

    Neale, Peta A; Stalter, Daniel; Tang, Janet Y M; Escher, Beate I

    2015-10-15

    Tattooing is becoming increasingly popular, particularly amongst young people. However, tattoo inks contain a complex mixture of chemical impurities that may pose a long-term risk for human health. As a first step towards the risk assessment of these complex mixtures we propose to assess the toxicological hazard potential of tattoo ink chemicals with cell-based bioassays. Targeted modes of toxic action and cellular endpoints included cytotoxicity, genotoxicity and adaptive stress response pathways. The studied tattoo inks, which were extracted with hexane as a proxy for the bioavailable fraction, caused effects in all bioassays, with the red and yellow tattoo inks having the greatest response, particularly inducing genotoxicity and oxidative stress response endpoints. Chemical analysis revealed the presence of polycyclic aromatic hydrocarbons in the tested black tattoo ink at concentrations twice the recommended level. The detected polycyclic aromatic hydrocarbons only explained 0.06% of the oxidative stress response of the black tattoo ink, thus the majority of the effect was caused by unidentified components. The study indicates that currently available tattoo inks contain components that induce adaptive stress response pathways, but to evaluate the risk to human health further work is required to understand the toxicokinetics of tattoo ink chemicals in the body. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Microbiological survey of commercial tattoo and permanent makeup inks available in the United States.

    Science.gov (United States)

    Nho, S W; Kim, S-J; Kweon, O; Howard, P C; Moon, M S; Sadrieh, N K; Cerniglia, C E

    2018-05-01

    Tattooing and use of permanent makeup (PMU) has dramatically increased over the last decade, with a concomitant increase in ink-related infections. The aim of this study was to determine whether micro-organisms are present, and if so, the number and their identification in the commercial tattoo and PMU inks available in the United States. We surveyed 85 unopened tattoo and PMU inks, purchased from 13 companies. We incubated 100 μl of ink samples on trypticase soy agar plates for bacterial growth, 7H10 Middlebrook medium for mycobacterial growth, and Sabouraud dextrose medium for fungal growth. In total, 42 inks were contaminated with micro-organisms (49%). Thirty-three inks were contaminated with bacteria, 2 inks with fungi, and 7 inks had both bacterial and fungal growth. Mycobacteria were not detected in any of the examined tattoo and PMU inks. In 26 inks, microbial concentrations ranged between 10 1 and 10 3 CFU per ml, but higher counts (>10 3 CFU per ml) were recorded in 16 inks. We identified 83 bacteria by their 16S rDNA sequences, including 20 genera and 49 species. Strains of Bacillus spp. (53%) were dominant, followed by Lysinibacillus fusiformis (7%) and Pseudomonas aeruginosa (5%). Thirty-four (41%) possibly clinically relevant strains were identified, including P. aeruginosa, Dermacoccus barathri and Roseomonas mucosa, some of which have been previously reported to be associated with human skin infections. The results indicate that commercial tattoo and PMU inks on the US market surveyed in this study contain a wide range of micro-organisms, including pathogenic bacteria. Microbial contaminants in tattoo and PMU inks are an emerging safety concern for public health. This study provides evidence that microbial contamination of tattoo and PMU inks available in the United States is more common than previously thought and highlights the importance of monitoring these products for potentially pathogenic micro-organisms. Published 2018. This article is a U

  8. Hydrodynamics of writing with ink.

    Science.gov (United States)

    Kim, Jungchul; Moon, Myoung-Woon; Lee, Kwang-Ryeol; Mahadevan, L; Kim, Ho-Young

    2011-12-23

    Writing with ink involves the supply of liquid from a pen onto a porous hydrophilic solid surface, paper. The resulting linewidth depends on the pen speed and the physicochemical properties of the ink and paper. Here we quantify the dynamics of this process using a combination of experiment and theory. Our experiments are carried out using a minimal pen, a long narrow tube that serves as a reservoir of liquid, which can write on a model of paper, a hydrophilic micropillar array. A minimal theory for the rate of wicking or spreading of the liquid is given by balancing the capillary force that drives the liquid flow and the resistance associated with flow through the porous substrate. This allows us to predict the shape of the front and the width of the line laid out by the pen, with results that are corroborated by our experiments.

  9. Martensitic transformation in zirconia

    International Nuclear Information System (INIS)

    Deville, Sylvain; Guenin, Gerard; Chevalier, Jerome

    2004-01-01

    We investigate by atomic force microscopy (AFM) the surface relief resulting from martensitic tetragonal to monoclinic phase transformation induced by low temperature autoclave aging in ceria-stabilized zirconia. AFM appears as a very powerful tool to investigate martensite relief quantitatively and with a great precision. The crystallographic phenomenological theory is used to predict the expected relief induced by the transformation, for the particular case of lattice correspondence ABC1, where tetragonal c axis becomes the monoclinic c axis. A model for variants spatial arrangement for this lattice correspondence is proposed and validated by the experimental observations. An excellent agreement is found between the quantitative calculations outputs and the experimental measurements at nanometer scale yielded by AFM. All the observed features are explained fully quantitatively by the calculations, with discrepancies between calculations and quantitative experimental measurements within the measurements and calculations precision range. In particular, the crystallographic orientation of the transformed grains is determined from the local characteristics of transformation induced relief. It is finally demonstrated that the strain energy is the controlling factor of the surface transformation induced by low temperature autoclave treatments in this material

  10. Properties of conductive thick-film inks

    Science.gov (United States)

    Holtze, R. F.

    1972-01-01

    Ten different conductive inks used in the fabrication of thick-film circuits were evaluated for their physical and handling properties. Viscosity, solid contents, and spectrographic analysis of the unfired inks were determined. Inks were screened on ceramic substrates and fired for varying times at specified temperatures. Selected substrates were given additional firings to simulate the heat exposure received if thick-film resistors were to be added to the same substrate. Data are presented covering the (1) printing characteristics, (2) solderability using Sn-63 and also a 4 percent silver solder, (3) leach resistance, (4) solder adhesion, and (5) wire bonding properties. Results obtained using different firing schedules were compared. A comparison was made between the various inks showing general results obtained for each ink. The changes in firing time or the application of a simulated resistor firing had little effect on the properties of most inks.

  11. Influence of incorporation method of sulfated zirconia in MCM-41 molecular sieve; Influencia do metodo de incorporacao da zirconia sulfatada na peneira molecular MCM-41

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, C.E.; Santos, J.S.B.; Cavalcante, J.N.A.; Andrade, M.R.A.; Sousa, B.V., E-mail: eduardopereira.eq@gmail.com [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Centro de Ciencia e Tecnologia

    2016-07-01

    Sulfated metal oxides and sulfated zirconia have attracted great attention in recent years due to its high catalytic activity. The sulfated zirconia has the function of assigning the acidic material, through the formation of Bronsted acids and Lewis sites. The incorporation of sulfated zirconia in MCM-41 molecular sieve was carried out through the techniques: dry and wet. The wet process involves the use of an excess of solution on the volume of the support pores. Therefore, the concentration of the metal precursor on the support depends on the solution concentration and the pore volume of the support. In the process of incorporating by dry, the volume of the solution containing the precursor does not exceed the pore volume of the support. After either procedure, the impregnated support must be dried in order to allow the precursor compound can be converted into a catalytically active phase. This study aims to evaluate two methods of incorporation of sulfated zirconia in the mesoporous molecular sieve MCM-41. The process of merger took for wet and dry impregnation. Through the XRD patterns it was possible to identify the presence of the hexagonal structure of the molecular sieve, as well as the tetragonal and monoclinic phases of zirconia. From the spectroscopic analysis in the infrared region to the method the wet, it was possible to identify the vibrational frequencies related to the merger of sulfated zirconia in the MCM-41 structure of the molecular sieve. (author)

  12. Rheological behavior of silver nanowire conductive inks during screen printing

    Energy Technology Data Exchange (ETDEWEB)

    Hemmati, Shohreh; Barkey, Dale P., E-mail: dpb@unh.edu; Gupta, Nivedita [University of New Hampshire, Department of Chemical Engineering (United States)

    2016-08-15

    The rheological behavior of silver nanowire (AgNW) suspensions adapted for screen printing inks was investigated. Aqueous silver nanowire inks consisting of AgNW (length of 30 μm, and diameter of 40 and 90 nm), dispersant and binder were formulated. The effect of AgNW content on the rheological behavior of the ink and the build-up of ink structure after screen printing were examined as they depend on applied shear and temperature. Rheological measurements under conditions that mimic the screen printing process were done to assess viscoelastic properties induced by flow alignment of the wires and the subsequent recovery of the low shear structure. The Stretched Exponential model (SEmo) was used to model the recovery process after screen printing to obtain the characteristic time of the recovery or build-up process. The characteristic time was determined at several temperatures to obtain the activation energy of recovery. The domination of Brownian motion or non-Brownian motion behavior can be characterized by a Peclet number, which is the ratio of shear rate to the rotational diffusion coefficient. The Peclet number and the dimensionless concentration of wires were used to assess the recovery mechanism. The steady viscosity at low and high shear rates was also treated by an activation energy analysis.

  13. Rheological behavior of silver nanowire conductive inks during screen printing

    Science.gov (United States)

    Hemmati, Shohreh; Barkey, Dale P.; Gupta, Nivedita

    2016-08-01

    The rheological behavior of silver nanowire (AgNW) suspensions adapted for screen printing inks was investigated. Aqueous silver nanowire inks consisting of AgNW (length of 30 μm, and diameter of 40 and 90 nm), dispersant and binder were formulated. The effect of AgNW content on the rheological behavior of the ink and the build-up of ink structure after screen printing were examined as they depend on applied shear and temperature. Rheological measurements under conditions that mimic the screen printing process were done to assess viscoelastic properties induced by flow alignment of the wires and the subsequent recovery of the low shear structure. The Stretched Exponential model (SEmo) was used to model the recovery process after screen printing to obtain the characteristic time of the recovery or build-up process. The characteristic time was determined at several temperatures to obtain the activation energy of recovery. The domination of Brownian motion or non-Brownian motion behavior can be characterized by a Peclet number, which is the ratio of shear rate to the rotational diffusion coefficient. The Peclet number and the dimensionless concentration of wires were used to assess the recovery mechanism. The steady viscosity at low and high shear rates was also treated by an activation energy analysis.

  14. Rheological behavior of silver nanowire conductive inks during screen printing

    International Nuclear Information System (INIS)

    Hemmati, Shohreh; Barkey, Dale P.; Gupta, Nivedita

    2016-01-01

    The rheological behavior of silver nanowire (AgNW) suspensions adapted for screen printing inks was investigated. Aqueous silver nanowire inks consisting of AgNW (length of 30 μm, and diameter of 40 and 90 nm), dispersant and binder were formulated. The effect of AgNW content on the rheological behavior of the ink and the build-up of ink structure after screen printing were examined as they depend on applied shear and temperature. Rheological measurements under conditions that mimic the screen printing process were done to assess viscoelastic properties induced by flow alignment of the wires and the subsequent recovery of the low shear structure. The Stretched Exponential model (SEmo) was used to model the recovery process after screen printing to obtain the characteristic time of the recovery or build-up process. The characteristic time was determined at several temperatures to obtain the activation energy of recovery. The domination of Brownian motion or non-Brownian motion behavior can be characterized by a Peclet number, which is the ratio of shear rate to the rotational diffusion coefficient. The Peclet number and the dimensionless concentration of wires were used to assess the recovery mechanism. The steady viscosity at low and high shear rates was also treated by an activation energy analysis.

  15. Oxidative stress-mediated cytotoxicity of zirconia nanoparticles on PC12 and N2a cells

    Energy Technology Data Exchange (ETDEWEB)

    Asadpour, Elham [Shiraz University of Medical Sciences, Anesthesiology and Critical Care Research Center (Iran, Islamic Republic of); Sadeghnia, Hamid R. [Mashhad University of Medical Sciences, Department of Pharmacology, Faculty of Medicine (Iran, Islamic Republic of); Ghorbani, Ahmad [Mashhad University of Medical Sciences, Pharmacological Research Center of Medicinal Plants (Iran, Islamic Republic of); Sedaghat, Mehran, E-mail: m-sedaghat81@yahoo.com [Mashhad University of Medical Sciences, Department of Neurosurgery (Iran, Islamic Republic of); Boroushaki, Mohammad T., E-mail: boroushakimt@mums.ac.ir [Mashhad University of Medical Sciences, Department of Pharmacology, Faculty of Medicine (Iran, Islamic Republic of)

    2016-01-15

    In recent years, there is a growing interest in the application of nanoparticles like zirconium dioxide (zirconia <100 nm), for many purposes. Since a comprehensive study on the toxic effects of zirconia has not been done, we decided to investigate the effects of zirconia nanoparticles on cultured PC12 and N2a cells. In this study, cytotoxic effect of different concentrations of zirconia nanoparticles at three different time intervals were evaluated using MTT and ROS (reactive oxygen species) assays. Also, Lipid peroxidation, glutathione (GSH) content changes, and DNA damage were measured. Zirconia nanoparticles caused a significant reduction in cell viability and GSH content of the cells, and induce a significant increase in intracellular ROS and MDA content of PC12 and N2a cells. Moreover, it increases the percentage of DNA tail of treated cells as compared with control group. Zirconia nanoparticles have cytotoxic and genotoxic effects in PC12 and N2a cells in a time and concentration-dependent manner in concentration more than 31 µg/mL.

  16. Nanoclays for polymer nanocomposites, paints, inks, greases

    Indian Academy of Sciences (India)

    ... rheological modifier for paints, inks and greases, drug delivery vehicle for controlled release of therapeutic agents, and nanoclays for industrial waste water as well as potable water treatment to make further step into green environment. A little amount of nanoclay can alter the entire properties of polymers, paints, inks and ...

  17. Non-aqueous pigmented inkjet inks

    NARCIS (Netherlands)

    DEROOVER, GEERT; Bernaerts, Katrien; HOOGMARTENS, IVAN

    2009-01-01

    A non-aqueous inkjet ink comprises a benzimidazolone pigment and a polymeric dispersant according to Formula (I): wherein, T represents hydrogen or a polymerization terminating group; Z represents theA non-aqueous inkjet ink comprises a benzimidazolone pigment and a polymeric dispersant according to

  18. N -Ink Printer Characterization With Barycentric Subdivision.

    Science.gov (United States)

    Babaei, Vahid; Hersch, Roger D

    2016-07-01

    Printing with a large number of inks, also called N -ink printing, is a challenging task. The challenges comprise spectral modeling of the printer, color separation, halftoning, and limitations of the amount of inks. Juxtaposed halftoning, a perfectly dot-off-dot halftoning method, has proved to be useful to address some of these challenges. However, for juxtaposed halftones, prediction of colors as a function of ink area coverages has not yet been fully investigated. The goal of this paper is to introduce a spectral prediction model for N -ink juxtaposed-halftone prints. As the area-coverage domain of juxtaposed inks forms a simplex, we propose a cellular subdivision of the area-coverage domain using the barycentric subdivision of simplexes. The barycentric subdivision provides algorithmically straightforward means to design and implement an N -ink color prediction model. Within the subdomain cells, the Yule-Nielsen spectral Neugebauer model is used for the spectral prediction. Our proposed model is highly accurate for prints with a large number of inks while requiring a relatively low number of calibration samples.

  19. Effect of accelerated aging on translucency of monolithic zirconia

    Directory of Open Access Journals (Sweden)

    O. Abdelbary

    2016-12-01

    Conclusion: Thickness of zirconia has significant effect on translucency. Aging has significant effect on thinner sections of zirconia. More research is required on zirconia towards making the material more translucent for its potential use as esthetic monolithic restoration.

  20. Chromatographic and electrophoretic approaches in ink analysis.

    Science.gov (United States)

    Zlotnick, J A; Smith, F P

    1999-10-15

    Inks are manufactured from a wide variety of substances that exhibit very different chemical behaviors. Inks designed for use in different writing instruments or printing methods have quite dissimilar components. Since the 1950s chromatographic and electrophoretic methods have played important roles in the analysis of inks, where compositional information may have bearing on the investigation of counterfeiting, fraud, forgery, and other crimes. Techniques such as paper chromatography and electrophoresis, thin-layer chromatography, high-performance liquid chromatography, gas chromatography, gel electrophoresis, and the relatively new technique of capillary electrophoresis have all been explored as possible avenues for the separation of components of inks. This paper reviews the components of different types of inks and applications of the above separation methods are reviewed.

  1. Sulfation of ceria-zirconia model automotive emissions control catalysts

    Science.gov (United States)

    Nelson, Alan Edwin

    Cerium-zirconium mixed metal oxides are used in automotive emissions control catalysts to regulate the partial pressure of oxygen near the catalyst surface. The near surface oxygen partial pressure is regulated through transfer of atomic oxygen from the ceria-zirconia solid matrix to the platinum group metals to form metal oxides capable of oxidizing carbon monoxide and unburned hydrocarbons. Although the addition of zirconium in the cubic lattice of ceria increases the oxygen storage capacity and thermal stability of the ceria matrix, the cerium-zirconium oxide system remains particularly susceptible to deactivation from sulfur compounds. While the overall effect of sulfur on these systems is understood (partially irreversible deactivation), the fundamental and molecular interaction of sulfur with ceria-zirconia remains a challenging problem. Ceria-zirconia metal oxide solid solutions have been prepared through co-precipitation with nitrate precursors. The prepared powders were calcined and subsequently formed into planer wafers and characterized for chemical and physical attributes. The prepared samples were subsequently exposed to a sulfur dioxide based environment and characterized with spectroscopic techniques to characterize the extent of sulfation and the nature of surface sulfur species. The extent of sulfation of the model ceria-zirconia systems was characterized with Auger electron spectroscopy (AES) prior to and after treatment in a microreactor. Strong dependencies were observed between the atomic ratio of ceria to zirconia and the extent of sulfation. In addition, the partial pressure of sulfur dioxide during treatments also correlated to the extent of sulfation, while temperature only slightly effected the extent of sulfation. The AES data suggests the gas phase sulfur dioxide preferentially chemisorbs on surface ceria atoms and the extent of sulfation is heavily dependent on sulfur dioxide concentrations and only slightly dependent on catalyst

  2. Influence of incorporation method of sulfated zirconia in MCM-41 molecular sieve

    International Nuclear Information System (INIS)

    Pereira, C.E.; Santos, J.S.B.; Cavalcante, J.N.A.; Andrade, M.R.A.; Sousa, B.V.

    2016-01-01

    Sulfated metal oxides and sulfated zirconia have attracted great attention in recent years due to its high catalytic activity. The sulfated zirconia has the function of assigning the acidic material, through the formation of Bronsted acids and Lewis sites. The incorporation of sulfated zirconia in MCM-41 molecular sieve was carried out through the techniques: dry and wet. The wet process involves the use of an excess of solution on the volume of the support pores. Therefore, the concentration of the metal precursor on the support depends on the solution concentration and the pore volume of the support. In the process of incorporating by dry, the volume of the solution containing the precursor does not exceed the pore volume of the support. After either procedure, the impregnated support must be dried in order to allow the precursor compound can be converted into a catalytically active phase. This study aims to evaluate two methods of incorporation of sulfated zirconia in the mesoporous molecular sieve MCM-41. The process of merger took for wet and dry impregnation. Through the XRD patterns it was possible to identify the presence of the hexagonal structure of the molecular sieve, as well as the tetragonal and monoclinic phases of zirconia. From the spectroscopic analysis in the infrared region to the method the wet, it was possible to identify the vibrational frequencies related to the merger of sulfated zirconia in the MCM-41 structure of the molecular sieve. (author)

  3. Grinding mechanism of zirconia toughened alumina

    International Nuclear Information System (INIS)

    Tsukuda, A.; Kondo, Y.; Yokota, K.

    1998-01-01

    In the grinding process, physical properties of ceramics affect both grinding mechanism and quality of ground surface. In this study we focused on fracture toughness of ceramics and the effect on grinding. A grinding test was carried out by single point grinding for ten different zirconia toughened alumina ceramics with different monoclinic zirconia contents. Effects of zirconia contents on the grinding mechanism and crack initiation were discussed. Copyright (1998) AD-TECH - International Foundation for the Advancement of Technology Ltd

  4. Dilemmas in zirconia bonding: A review

    Directory of Open Access Journals (Sweden)

    Obradović-Đuričić Kosovka

    2013-01-01

    Full Text Available This article presents a literature review on the resin bond to zirconia ceramic. Modern esthetic dentistry has highly recognized zirconia, among other ceramic materials. Biocompatibility of zirconia, chemical and dimensional stability, excellent mechanical properties, all together could guarantee optimal therapeutical results in complex prosthodontic reconstruction. On the other hand, low thermal degradation, aging of zirconia as well as problematic bonding of zirconia framework to dental luting cements and tooth structures, opened the room for discussion concerning their clinical durability. The well known methods of mechanical and chemical bonding used on glass-ceramics are not applicable for use with zirconia. Therefore, under critical clinical situations, selection of the bonding mechanism should be focused on two important points: high initial bond strength value and long term bond strength between zirconia-resin interface. Also, this paper emphases the use of phosphate monomer luting cements on freshly air-abraded zirconia as the simplest and most effective way for zirconia cementation procedure today.

  5. SEM evaluation of human gingival fibroblasts growth onto CAD/CAM zirconia and veneering ceramic for zirconia

    Science.gov (United States)

    Zizzari, Vincenzo; Borelli, Bruna; De Colli, Marianna; Tumedei, Margherita; Di Iorio, Donato; Zara, Susi; Sorrentino, Roberto; Cataldi, Amelia; Gherlone, Enrico Felice; Zarone, Fernando; Tetè, Stefano

    2013-01-01

    Summary Aim To evaluate the growth of Human Gingival Fibroblasts (HGFs) cultured onto sample discs of CAD/CAM zirconia and veneering ceramic for zirconia by means of Scanning Electron Microscope (SEM) analysis at different experimental times. Methods A total of 26 experimental discs, divided into 2 groups, were used: Group A) CAD/CAM zirconia (3Y-TZP) discs (n=13); Group B) veneering ceramic for zirconia discs (n=13). HGFs were obtained from human gingival biopsies, isolated and placed in culture plates. Subsequently, cells were seeded on experimental discs at 7,5×103/cm2 concentration and cultured for a total of 7 days. Discs were processed for SEM observation at 3h, 24h, 72h and 7 days. Results In Group A, after 3h, HGFs were adherent to the surface and showed a flattened profile. The disc surface covered by HGFs resulted to be wider in Group A than in Group B samples. At SEM observation, after 24h and 72h, differences in cell attachment were slightly noticeable between the groups, with an evident flattening of HGFs on both surfaces. All differences between Group A and group B became less significant after 7 days of culture in vitro. Conclusions SEM analysis of HGFs showed differences in terms of cell adhesion and proliferation, especially in the early hours of culture. Results showed a better adhesion and cell growth in Group A than in Group B, especially up to 72h in vitro. Differences decreased after 7 days, probably because of the rougher surface of CAD/CAM zirconia, promoting better cell adhesion, compared to the smoother surface of veneering ceramic. PMID:24611089

  6. Studies of Ink Trapping III Direct Detection of Small Air Bubbles in Ink Layer

    Directory of Open Access Journals (Sweden)

    Ikuo Naito

    2006-12-01

    Full Text Available Ink trappings were studied by using polyethylene terephthalate (PET film with black inks for offset proofing and synthetic paper. By observing printed matter from reverse side through the PET film, we detected many air bubbles in the ink layer and between the ink layer and the PET film. They are classified roughly to two groups, small number of large ones (φ = 2 - 5 μm and many small ones (φ = 0.5 - 1.0 μm. The former ones were fixed air bubbles during the trapping. The latter ones decreased according to increase the amount of ink trapped (y. Because number of the air bubbles (Nair bubble increased with increasing the ink distribution time, they seemed to be yielded by suspension of air into the ink layer during ink distribution. By observing printed surface, we also detected many ink peaks (immediately after the trapping and pinholes (at 24 h. The numbers of the ink peaks and pinholes (Nink peak and Npinhole, respectively decreased also with increasing the y value and increased with increasing the ink distribution time. We studied effects of nip width on these values (distribution time = 2 min.; nip width = 2, 3 and 4 mm. The Nair bubble value decreased with increasing nip width contrary to increase the Nink peak and Npinhole values. The effects can be represented by differences in the values of 2 and 4 mm nip widths. At y = 2 gm-2, the difference in the Nair bubble value is about one third (synthetic paper ink or a half (offset proofing ink of the difference in the Nink peak values.

  7. Terahertz pulse generation from metal nanoparticle ink

    Science.gov (United States)

    Kato, Kosaku; Takano, Keisuke; Tadokoro, Yuzuru; Phan, Thanh Nhat Khoa; Nakajima, Makoto

    2016-11-01

    Terahertz pulse generation from metallic nanostructures irradiated by femtosecond laser pulses is of interest because the conversion efficiency from laser pulses to terahertz waves is increased by the local field enhancement resulting from the plasmon oscillation. In this talk we present our recent study on terahertz generation from metal nanoparticle ink. We baked a silver nanoparticle ink spin-coated onto a glass coverslip in various temperatures. On the surface of the baked ink, bumpy nanostructures are spontaneously formed, and the average size of bumps depends on the baking temperature. These structures are expected to lead to local field enhancement and then large nonlinear polarizations on the surface. The baked ink was irradiated by the output of regeneratively amplified Ti:sapphire femtosecond laser at an incidence angle of 45°. Waveforms of generated terahertz pulses are detected by electro-optical sampling. The generation efficiency was high when the average diameter of bumps was around 100 nm, which is realized when the ink is baked in 205 to 235°C in our setup. One of our next research targets is terahertz wave generation from micro-patterned metallic nanoparticle ink. It is an advantage of the metal nanoparticle ink that by using inkjet printers one can fabricate various patterns with micrometer scales, in which terahertz waves have a resonance. Combination of microstructures made by a printer and nanostructure spontaneously formed in the baking process will provide us terahertz emitters with unique frequency characteristics.

  8. Characteristics of porous zirconia coated with hydroxyapatite

    Indian Academy of Sciences (India)

    However, porous hydroxyapatite bodies are mechanically weak and brittle, which makes shaping and implantation difficult. One way to solve this problem is to introduce a strong porous network onto which hydroxyapatite coating is applied. In this study, porous zirconia and alumina-added zirconia ceramics were prepared ...

  9. Surface degradation of nanocrystalline zirconia dental implants

    NARCIS (Netherlands)

    Ocelík, Václav; Schepke, Ulf; Rasoul, Hamid Haji; Cune, Marco S.; De Hosson, Jeff Th M.

    2017-01-01

    Yttria-stabilized zirconia prepared by hot isostatic pressing represents attractive material for biomedical applications. In this work the degradation of yttria-stabilized zirconia dental implants abutments due to the tetragonal to monoclinic phase transformation after one year of clinical use was

  10. Evolution of the nickel/zirconia interface

    International Nuclear Information System (INIS)

    Shinde, S.L.; Olson, D.A.; De Jonghe, L.C.; Miller, R.A.

    1986-01-01

    The changes taking place at the nickel zirconia interface during oxidation in air at 900 0 C were studied using analytical electron microscopy (AEM). The nickel oxide layer growing at the interface and the stabilizers used in zirconia interact, giving different interface morphologies

  11. Ag–graphene hybrid conductive ink for writing electronics

    International Nuclear Information System (INIS)

    Xu, L Y; Yang, G Y; Jing, H Y; Han, Y D; Wei, J

    2014-01-01

    With the aim of preparing a method for the writing of electronics on paper by the use of common commercial rollerball pens loaded with conductive ink, hybrid conductive ink composed of Ag nanoparticles (15 wt%) and graphene–Ag composite nanosheets (0.15 wt%) formed by depositing Ag nanoparticles (∼10 nm) onto graphene sheets was prepared for the first time. Owing to the electrical pathway effect of graphene and the decreased contact resistance of graphene junctions by depositing Ag nanoparticles (NPs) onto graphene sheets, the concentration of Ag NPs was significantly reduced while maintaining high conductivity at a curing temperature of 100 ° C. A typical resistivity value measured was 1.9 × 10 −7  Ω m, which is 12 times the value for bulk silver. Even over thousands of bending cycles or rolling, the resistance values of writing tracks only increase slightly. The stability and flexibility of the writing circuits are good, demonstrating the promising future of this hybrid ink and direct writing method. (paper)

  12. Failure analysis of fractured dental zirconia implants.

    Science.gov (United States)

    Gahlert, M; Burtscher, D; Grunert, I; Kniha, H; Steinhauser, E

    2012-03-01

    The purpose of the present study was the macroscopic and microscopic failure analysis of fractured zirconia dental implants. Thirteen fractured one-piece zirconia implants (Z-Look3) out of 170 inserted implants with an average in situ period of 36.75±5.34 months (range from 20 to 56 months, median 38 months) were prepared for macroscopic and microscopic (scanning electron microscopy [SEM]) failure analysis. These 170 implants were inserted in 79 patients. The patient histories were compared with fracture incidences to identify the reasons for the failure of the implants. Twelve of these fractured implants had a diameter of 3.25 mm and one implant had a diameter of 4 mm. All fractured implants were located in the anterior side of the maxilla and mandibula. The patient with the fracture of the 4 mm diameter implant was adversely affected by strong bruxism. By failure analysis (SEM), it could be demonstrated that in all cases, mechanical overloading caused the fracture of the implants. Inhomogeneities and internal defects of the ceramic material could be excluded, but notches and scratches due to sandblasting of the surface led to local stress concentrations that led to the mentioned mechanical overloading by bending loads. The present study identified a fracture rate of nearly 10% within a follow-up period of 36.75 months after prosthetic loading. Ninety-two per cent of the fractured implants were so-called diameter reduced implants (diameter 3.25 mm). These diameter reduced implants cannot be recommended for further clinical use. Improvement of the ceramic material and modification of the implant geometry has to be carried out to reduce the failure rate of small-sized ceramic implants. Nevertheless, due to the lack of appropriate laboratory testing, only clinical studies will demonstrate clearly whether and how far the failure rate can be reduced. © 2011 John Wiley & Sons A/S.

  13. An intelligence ink for photocatalytic films.

    Science.gov (United States)

    Mills, Andrew; Wang, Jishun; Lee, Soo-Keun; Simonsen, Morten

    2005-06-07

    An ink is described which, when printed or coated onto a photocatalyst film, changes colour irreversibly and rapidly upon UV activation of the photocatalyst film and at a rate commensurate with its activity.

  14. Zirconia-based solid state chemical gas sensors

    CERN Document Server

    Zhuiykov, S

    2000-01-01

    This paper presents an overview of chemical gas sensors, based on solid state technology, that are sensitive to environmental gases, such as O sub 2 , SO sub x , NO sub x , CO sub 2 and hydrocarbons. The paper is focussed on performance of electrochemical gas sensors that are based on zirconia as a solid electrolyte. The paper considers sensor structures and selection of electrode materials. Impact of interfaces on sensor performance is discussed. This paper also provides a brief overview of electrochemical properties of zirconia and their effect on sensor performance. Impact of auxiliary materials on sensors performance characteristics, such as sensitivity, selectivity, response time and recovery time, is also discussed. Dual gas sensors that can be applied for simultaneous monitoring of the concentration of both oxygen and other gas phase components, are briefly considered

  15. Tattoo inks in general usage contain nanoparticles

    DEFF Research Database (Denmark)

    Høgsberg, T; Löschner, Katrin; Löf, D

    2011-01-01

    the particle sizes in tattoo inks in general usage. Methods The particle size was measured by laser diffraction, electron microscopy and X-ray diffraction. Results The size of the pigments could be divided into three main classes. The black pigments were the smallest, the white pigments the largest...... in general usage is new and may contribute to the understanding of tattoo ink kinetics. How the body responds to NP tattoo pigments should be examined further....

  16. Synthesis of Ceria Zirconia Oxides using Solvothermal Treatment

    Directory of Open Access Journals (Sweden)

    Machmudah Siti

    2018-01-01

    Full Text Available Ceria oxide (CeO2 is widely used as catalyst with high oxygen storage capacity at low temperature. The addition of zirconia oxide (ZrO2 to CeO2 can enhance oxygen storage capacity as well as thermal stability. In this work, ceria zirconia oxides has been synthesized via a low temperature solvothermal treatment in order to produce ceria zirconia oxides composite with high oxygen storage capacity as electrolyte of solid oxide fuel cells (SOFC. Under solvothermal conditions, solvent may control the direction of crystal growth, morphology, particle size and size distribution, because of the controllability of thermodynamics and transport properties by pressure and temperature. Water, mixed of water and ethanol (70/30 vol/vol, and mixed of water and ethylene glycol (70/30 vol/vol were used as solvent, while Ce(NO33 and ZrO(NO32 with 0.06 M concentration were used as precursor. The experiments were conducted at temperature of 150 °C and pressure for 2 h in a Teflon-lined autoclave of 100 mL volume. The synthesized products were dried at 60 °C for 6 and 12 h and then calcined at 900 °C for 6 h. The particle products were characterized using SEM, XRD, TG/DTA, and Potentiostat. The results showed that the morphology of particles formed were affected by the solvent. Solid plate shaped particles were produced in water, and tend to be pore with the addition of ethylene glycol. The addition of ethanol decreased the size of particles with sphere shaped. The XRD pattern indicated that ceria-zirconia oxides particles are uniformly distributed in the structure to form a homogeneous solid solution. Based on the electrochemical analysis, ceria zirconia oxides produced via solvothermal synthesis had high conductivity ion of 0.5594 S/cm, which is higher than minimum conductivity ion requirement of 0.01 S/cm for SOFC electrolyte. It indicated that ceria zirconia oxides produced via solvothermal synthesis is suitable for SOFC electrolyte.

  17. A diffusive ink transport model for lipid dip-pen nanolithography

    Science.gov (United States)

    Urtizberea, A.; Hirtz, M.

    2015-09-01

    Despite diverse applications, phospholipid membrane stacks generated by dip-pen nanolithography (DPN) still lack a thorough and systematic characterization that elucidates the whole ink transport process from writing to surface spreading, with the aim of better controlling the resulting feature size and resolution. We report a quantitative analysis and modeling of the dependence of lipid DPN features (area, height and volume) on dwell time and relative humidity. The ink flow rate increases with humidity in agreement with meniscus size growth, determining the overall feature size. The observed time dependence indicates the existence of a balance between surface spreading and the ink flow rate that promotes differences in concentration at the meniscus/substrate interface. Feature shape is controlled by the substrate surface energy. The results are analyzed within a modified model for the ink transport of diffusive inks. At any humidity the dependence of the area spread on the dwell time shows two diffusion regimes: at short dwell times growth is controlled by meniscus diffusion while at long dwell times surface diffusion governs the process. The critical point for the switch of regime depends on the humidity.Despite diverse applications, phospholipid membrane stacks generated by dip-pen nanolithography (DPN) still lack a thorough and systematic characterization that elucidates the whole ink transport process from writing to surface spreading, with the aim of better controlling the resulting feature size and resolution. We report a quantitative analysis and modeling of the dependence of lipid DPN features (area, height and volume) on dwell time and relative humidity. The ink flow rate increases with humidity in agreement with meniscus size growth, determining the overall feature size. The observed time dependence indicates the existence of a balance between surface spreading and the ink flow rate that promotes differences in concentration at the meniscus

  18. Wear mechanisms of toughened zirconias

    International Nuclear Information System (INIS)

    Becker, P.C.; Libsch, T.A.; Rhee, S.K.

    1985-01-01

    The dry friction and wear behavior of toughened zirconias against hardened steel was studied using the falex ring and block technique. Three experimental ZrO 2 -Y 2 O 3 ceramics and two commerical ZrO 2 -MgO ceramics were investigated. Each ceramic was tested at 500 and 2000 rpm at normal loads in the range 2.3 to 40.8 kg. Significant trends in the friction and wear data were found correlating composition, test speeds, and loads. Microstructural examination of the ring, ceramic block, and wear debris has shown that the wear process is very complex and incorporates a number of mechanisms

  19. Stability of zirconia sol in the presence of various inorganic electrolytes

    Directory of Open Access Journals (Sweden)

    Marković Jelena P.

    2013-01-01

    Full Text Available Zirconia sol was prepared from zirconium oxychloride solutions by forced hydrolysis at 102ºC. The prepared sol consisted of almost spherical, monoclinic, hydrated zirconia particles 61 nm in diameter. The stability of zirconia sol in the presence of various inorganic electrolytes (LiCl, NaCl, KCl, CsCl, KBr, KI, KNO3, and K2SO4 was studied by potentiometric titration method. Dependence of the critical concentration of coagulation (CCC on the dispersion pH was determined for all studied electrolytes. The critical coagulation concentration values, for all investigated electrolytes, are lower at higher pH. These values for all 1:1 electrolytes are equal in the range of experimental error. For a given pH value, CCCs of K2SO4 are 3-4 orders of magnitude lower than the corresponding values for 1:1 electrolytes. [Projekat Ministarstva nauke republike Srbije, br. III 45012

  20. The novel mTORC1/2 dual inhibitor INK-128 suppresses survival and proliferation of primary and transformed human pancreatic cancer cells

    International Nuclear Information System (INIS)

    Lou, Hai-zhou; Weng, Xiao-chuan; Pan, Hong-ming; Pan, Qin; Sun, Peng; Liu, Li-li; Chen, Bin

    2014-01-01

    Highlights: • INK-128 inhibits the survival and growth of human pancreatic cancer cells. • INK-128 induced pancreatic cancer cell apoptosis and necrosis simultaneously. • INK-128 blocks mTORC1/2 activation simultaneously in pancreatic cancer cells. • INK-128 down-regulates cyclin D1 and causes pancreatic cancer cell cycle arrest. • INK-128 significantly increases sensitivity of pancreatic cancer cells to gemcitabine. - Abstract: Pancreatic cancer has one of worst prognosis among all human malignancies around the world, the development of novel and more efficient anti-cancer agents against this disease is urgent. In the current study, we tested the potential effect of INK-128, a novel mammalian target of rapamycin (mTOR) complex 1 and 2 (mTORC1/2) dual inhibitor, against pancreatic cancer cells in vitro. Our results demonstrated that INK-128 concentration- and time-dependently inhibited the survival and growth of pancreatic cancer cells (both primary cells and transformed cells). INK-128 induced pancreatic cancer cell apoptosis and necrosis simultaneously. Further, INK-128 dramatically inhibited phosphorylation of 4E-binding protein 1 (4E-BP1), ribosomal S6 kinase 1 (S6K1) and Akt at Ser 473 in pancreatic cancer cells. Meanwhile, it downregulated cyclin D1 expression and caused cell cycle arrest. Finally, we found that a low concentration of INK-128 significantly increased the sensitivity of pancreatic cancer cells to gemcitabine. Together, our in vitro results suggest that INK-128 might be further investigated as a novel anti-cancer agent or chemo-adjuvant for pancreatic cancer treatment

  1. The novel mTORC1/2 dual inhibitor INK-128 suppresses survival and proliferation of primary and transformed human pancreatic cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Lou, Hai-zhou [Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou 310016 (China); Weng, Xiao-chuan [Department of Anesthesiology, Hangzhou Xia-sha Hospital, Hangzhou 310018 (China); Pan, Hong-ming; Pan, Qin [Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou 310016 (China); Sun, Peng [Department of Medical Oncology, Sun Yat-Sen University Cancer Center, Guangzhou 510060 (China); Liu, Li-li [Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou 310016 (China); Chen, Bin, E-mail: chenbinhangzhou126@126.com [Department of Hepatopancreatobiliary Surgery, First People’s Hospital of Hangzhou, Hangzhou 310006 (China)

    2014-07-25

    Highlights: • INK-128 inhibits the survival and growth of human pancreatic cancer cells. • INK-128 induced pancreatic cancer cell apoptosis and necrosis simultaneously. • INK-128 blocks mTORC1/2 activation simultaneously in pancreatic cancer cells. • INK-128 down-regulates cyclin D1 and causes pancreatic cancer cell cycle arrest. • INK-128 significantly increases sensitivity of pancreatic cancer cells to gemcitabine. - Abstract: Pancreatic cancer has one of worst prognosis among all human malignancies around the world, the development of novel and more efficient anti-cancer agents against this disease is urgent. In the current study, we tested the potential effect of INK-128, a novel mammalian target of rapamycin (mTOR) complex 1 and 2 (mTORC1/2) dual inhibitor, against pancreatic cancer cells in vitro. Our results demonstrated that INK-128 concentration- and time-dependently inhibited the survival and growth of pancreatic cancer cells (both primary cells and transformed cells). INK-128 induced pancreatic cancer cell apoptosis and necrosis simultaneously. Further, INK-128 dramatically inhibited phosphorylation of 4E-binding protein 1 (4E-BP1), ribosomal S6 kinase 1 (S6K1) and Akt at Ser 473 in pancreatic cancer cells. Meanwhile, it downregulated cyclin D1 expression and caused cell cycle arrest. Finally, we found that a low concentration of INK-128 significantly increased the sensitivity of pancreatic cancer cells to gemcitabine. Together, our in vitro results suggest that INK-128 might be further investigated as a novel anti-cancer agent or chemo-adjuvant for pancreatic cancer treatment.

  2. Tungstophosphoric acid supported onto hydrous zirconia ...

    Indian Academy of Sciences (India)

    Unknown

    Hydrous zirconia; heteropolyacid; morphology; particle size; acidity. 1. Introduction. Catalysis by .... chemisorbed on the sample in every pulse was detected by a thermal ..... qualitative organic analysis (New York: Longman), Ch. 3,. 4th ed.

  3. Ink-Jet Printer Forms Solar-Cell Contacts

    Science.gov (United States)

    Alexander, Paul, Jr.; Vest, R. W.; Binford, Don A.; Tweedell, Eric P.

    1988-01-01

    Contacts formed in controllable patterns with metal-based inks. System forms upper metal contact patterns on silicon photovoltaic cells. Uses metallo-organic ink, decomposes when heated, leaving behind metallic, electrically conductive residue in printed area.

  4. Fluency over the monoclinic zirconia indentation

    International Nuclear Information System (INIS)

    Pereira, A.S.; Jornada, J.A.H. da

    1992-01-01

    It was investigated the environment and the time dependence of the Vickers microhardness of monoclinic zirconia single-crystals. The samples were kept at room temperature and the identifications were performed for different environments (air, toluene and water). An indentation creep process was observed for the samples indented is moist media, indicating for a water activated plastic relaxation mechanism. The possible influence of such effect in the fatigue and phase transformations mechanisms of zirconia based ceramics is discussed. (author)

  5. Synthesis of monodisperse silver nanoparticles for ink-jet printed flexible electronics

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Zhiliang; Zhang Xingye; Xin Zhiqing; Deng Mengmeng; Wen Yongqiang; Song Yanlin, E-mail: zhangxy@iccas.ac.cn, E-mail: ylsong@iccas.ac.cn [Beijing National Laboratory for Molecular Sciences (BNLMS), Key Lab of Organic Solids, Laboratory of New Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

    2011-10-21

    In this study, monodisperse silver nanoparticles were synthesized with a new reduction system consisting of adipoyl hydrazide and dextrose at ambient temperature. By this facile and rapid approach, high concentration monodisperse silver nanoparticles were obtained on a large scale at low protectant/AgNO{sub 3} mass ratio which was highly beneficial to low cost and high conductivity. Based on the synthesized monodisperse silver nanoparticles, conductive inks were prepared with water, ethanol and ethylene glycol as solvents, and were expected to be more environmentally friendly. A series of electrocircuits were fabricated by ink-jet printing silver nanoparticle ink on paper substrate with a commercial printer, and they had low resistivity in the range of 9.18 x 10{sup -8}-8.76 x 10{sup -8} {Omega} m after thermal treatment at 160 {sup 0}C for 30 min, which was about five times that of bulk silver (1.586 x 10{sup -8} {Omega} m). Moreover, a radio frequency identification (RFID) antenna was fabricated by ink-jet printing, and 6 m wireless identification was realized after an Alien higgs-3 chip was mounted on the printed antenna by the flip-chip method. These flexible electrocircuits produced by ink-jet printing would have enormous potential for low cost electrodes and sensor devices.

  6. Synthesis of monodisperse silver nanoparticles for ink-jet printed flexible electronics

    International Nuclear Information System (INIS)

    Zhang Zhiliang; Zhang Xingye; Xin Zhiqing; Deng Mengmeng; Wen Yongqiang; Song Yanlin

    2011-01-01

    In this study, monodisperse silver nanoparticles were synthesized with a new reduction system consisting of adipoyl hydrazide and dextrose at ambient temperature. By this facile and rapid approach, high concentration monodisperse silver nanoparticles were obtained on a large scale at low protectant/AgNO 3 mass ratio which was highly beneficial to low cost and high conductivity. Based on the synthesized monodisperse silver nanoparticles, conductive inks were prepared with water, ethanol and ethylene glycol as solvents, and were expected to be more environmentally friendly. A series of electrocircuits were fabricated by ink-jet printing silver nanoparticle ink on paper substrate with a commercial printer, and they had low resistivity in the range of 9.18 x 10 -8 -8.76 x 10 -8 Ω m after thermal treatment at 160 0 C for 30 min, which was about five times that of bulk silver (1.586 x 10 -8 Ω m). Moreover, a radio frequency identification (RFID) antenna was fabricated by ink-jet printing, and 6 m wireless identification was realized after an Alien higgs-3 chip was mounted on the printed antenna by the flip-chip method. These flexible electrocircuits produced by ink-jet printing would have enormous potential for low cost electrodes and sensor devices.

  7. A diffusive ink transport model for lipid dip-pen nanolithography.

    Science.gov (United States)

    Urtizberea, A; Hirtz, M

    2015-10-14

    Despite diverse applications, phospholipid membrane stacks generated by dip-pen nanolithography (DPN) still lack a thorough and systematic characterization that elucidates the whole ink transport process from writing to surface spreading, with the aim of better controlling the resulting feature size and resolution. We report a quantitative analysis and modeling of the dependence of lipid DPN features (area, height and volume) on dwell time and relative humidity. The ink flow rate increases with humidity in agreement with meniscus size growth, determining the overall feature size. The observed time dependence indicates the existence of a balance between surface spreading and the ink flow rate that promotes differences in concentration at the meniscus/substrate interface. Feature shape is controlled by the substrate surface energy. The results are analyzed within a modified model for the ink transport of diffusive inks. At any humidity the dependence of the area spread on the dwell time shows two diffusion regimes: at short dwell times growth is controlled by meniscus diffusion while at long dwell times surface diffusion governs the process. The critical point for the switch of regime depends on the humidity.

  8. Improved verification methods for OVI security ink

    Science.gov (United States)

    Coombs, Paul G.; Markantes, Tom

    2000-04-01

    Together, OVP Security Pigment in OVI Security Ink, provide an excellent method of overt banknote protection. The effective use of overt security feature requires an educated public. The rapid rise in computer-generated counterfeits indicates that consumers are not as educate das to banknote security features as they should be. To counter the education issue, new methodologies have been developed to improve the validation of banknotes using the OVI ink feature itself. One of the new methods takes advantage of the overt nature of the product's optically variable effect. Another method utilizes the unique optical interference characteristics provided by the OVP platelets.

  9. Dynamic Colour Possibilities and Functional Properties of Thermochromic Printing Inks

    OpenAIRE

    Rahela Kulcar; Marta Klanjsek Gunde; Nina Knesaurek

    2012-01-01

    Thermochromic printing inks change their colour regarding the change in temperature and they are one of the major groups of colour-changing inks. One of the most frequently used thermochromic material in printing inks are leuco dyes. The colour of thermochromic prints is dynamic, it is not just temperature-dependent, but it also depends on thermal history. The effect is described by colour hysteresis. This paper aims at discussing general aspects of thermochromic inks, dynamic colorimetric pr...

  10. Precipitation in partially stabilized zirconia

    International Nuclear Information System (INIS)

    Bansal, G.K.

    1975-01-01

    Transmission electron microscopy was used to study the substructure of partially stabilized ZrO 2 (PSZ) samples, i.e., 2-phase systems containing both cubic and monoclinic modifications of zirconia, after various heat treatments. Monoclinic ZrO 2 exists as (1) isolated grains within the polycrystalline aggregate (a grain- boundary phase) and (2) small plate-like particles within cubic grains. These intragranular precipitates are believed to contribute to the useful properties of PSZ via a form of precipitation hardening. These precipitates initially form as tetragonal ZrO 2 , with a habit plane parallel to the brace 100 brace matrix planes. The orientation relations between the tetragonal precipitates and the cubic matrix are brace 100 brace/sub matrix/ 2 parallel brace 100 brace /sub precipitate/ or (001)/sub precipitate/ and broken bracket 100 broken bracket/sub matrix/ 2 parallel broken bracket 100 broken bracket/sub precipitate/ or [001]/sub precipitate/. (U.S.)

  11. An overview of monolithic zirconia in dentistry

    Directory of Open Access Journals (Sweden)

    Özlem Malkondu

    2016-07-01

    Full Text Available Zirconia restorations have been used successfully for years in dentistry owing to their biocompatibility and good mechanical properties. Because of their lack of translucency, zirconia cores are generally veneered with porcelain, which makes restorations weaker due to failure of the adhesion between the two materials. In recent years, all-ceramic zirconia restorations have been introduced in the dental sector with the intent to solve this problem. Besides the elimination of chipping, the reduced occlusal space requirement seems to be a clear advantage of monolithic zirconia restorations. However, scientific evidence is needed to recommend this relatively new application for clinical use. This mini-review discusses the current scientific literature on monolithic zirconia restorations. The results of in vitro studies suggested that monolithic zirconia may be the best choice for posterior fixed partial dentures in the presence of high occlusal loads and minimal occlusal restoration space. The results should be supported with much more in vitro and particularly in vivo studies to obtain a final conclusion.

  12. Dynamic Colour Possibilities and Functional Properties of Thermochromic Printing Inks

    Directory of Open Access Journals (Sweden)

    Rahela Kulcar

    2012-07-01

    Full Text Available Thermochromic printing inks change their colour regarding the change in temperature and they are one of the major groups of colour-changing inks. One of the most frequently used thermochromic material in printing inks are leuco dyes. The colour of thermochromic prints is dynamic, it is not just temperature-dependent, but it also depends on thermal history. The effect is described by colour hysteresis. This paper aims at discussing general aspects of thermochromic inks, dynamic colorimetric properties of leuco dye-based thermochromic inks, their stability and principle of variable-temperature colour measurement. Thermochromic material is protected in round-shaped capsules. They are much larger than pigments in conventional inks. The polymer envelopes of pigment capsules are more stable against oxidation than the binder. If these envelopes are damaged, the dynamic colour is irreversibly lost. Our aim is to analyse the colorimetric properties of several reversible screen-printed UV-curing leuco dye thermochromic inks with different activation temperatures printed on paper. A small analysis of irreversible thermochromic inks will be presented for comparison with reversible thermochromic inks. Moreover, so as to show interesting possibilities, a combination of different inks was made, an irreversible thermochromic ink was printed on top of the red and blue reversible thermochromic inks. Special attention was given to the characterization of colour hysteresis and the meaning of activation temperature.

  13. Preparation of porous zirconia microspheres by internal gelation method

    International Nuclear Information System (INIS)

    Pathak, Sachin S.; Pius, I.C.; Bhanushali, R.D.; Rao, T.V. Vittal; Mukerjee, S.K.

    2008-01-01

    A modified internal gelation process for the preparation of porous zirconia microspheres has been developed. The conventional method has been modified by adding a surfactant in the feed broth. The effects of variation of surfactant concentration, washing techniques and temperature of calcination on the pore volume and the surface area of the microspheres have been studied. The conditions were optimized to obtain porous stable microspheres suitable for various applications. The microspheres were characterized by surface area analysis, pore volume analysis, thermogravimetric analysis and X-ray diffraction. The ion exchange behavior was studied using pH titration

  14. Black tattoo inks induce reactive oxygen species production correlating with aggregation of pigment nanoparticles and product brand but not with the polycyclic aromatic hydrocarbon content.

    Science.gov (United States)

    Høgsberg, Trine; Jacobsen, Nicklas Raun; Clausen, Per Axel; Serup, Jørgen

    2013-07-01

    Black tattoo inks are composed of carbon nanoparticles, additives and water and may contain polycyclic aromatic hydrocarbons (PAHs). We aimed to clarify whether reactive oxygen species (ROS) induced by black inks in vitro is related to pigment chemistry, physico-chemical properties of the ink particles and the content of chemical additives and contaminants including PAHs. The study included nine brands of tattoo inks of six colours each (black, red, yellow, blue, green and white) and two additional black inks of different brands (n = 56). The ROS formation potential was determined by the dichlorofluorescein (DCFH) assay. A semiquantitative method was developed for screening extractable organic compounds in tattoo ink based on gas chromatography-mass spectrometry (GC-MS) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Two black inks produced high amounts of ROS. Peroxyl radicals accounted for up to 72% of the free radicals generated, whereas hydroxyl radicals and H₂O₂ accounted for inks aggregated strongly in water in contrast to the other black inks. They did not exhibit any shared pattern in PAHs and other organic substances. Aggregation was exclusively shared by all ink colours belonging to the same two brands. Ten of 11 black inks had PAH concentrations exceeding the European Council's recommended level, and all 11 exceeded the recommended level for benzo(a)pyrene. It is a new finding that aggregation of tattoo pigment particles correlates with ROS production and brand, independently of chemical composition including PAHs. ROS is hypothesized to be implicated in minor clinical symptoms. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Towards conducting inks: polypyrrole-silver colloids

    Czech Academy of Sciences Publication Activity Database

    Omastová, M.; Bober, Patrycja; Morávková, Zuzana; Peřinka, N.; Kaplanová, M.; Syrový, T.; Hromádková, Jiřina; Trchová, Miroslava; Stejskal, Jaroslav

    2014-01-01

    Roč. 122, 10 March (2014), s. 296-302 ISSN 0013-4686 R&D Projects: GA TA ČR TE01020022; GA ČR(CZ) GA13-00270S Institutional support: RVO:61389013 Keywords : conducting inks * polypyrrole * colloids Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 4.504, year: 2014

  16. Electron Beam curing of intaglio inks

    International Nuclear Information System (INIS)

    O'Brien, T.

    1984-01-01

    Press trials conducted by the US Bureau of Engraving and Printing at the National Bank of Denmark in September 8-21, 1982, clearly indicated the feasibility of Electron Beam (EB) curing for web intaglio printing. These trials, some at continuous press runs of up to six hours, gave positive results for virtually all our requirements including: print quality, press speeds, ability to print both sides of the web on one pass through a press, acceptable ink curing at one megarad or less, and minimum substrate deterioration or loss of moisture. In addition, these trials demonstrated many advantages over thermal curing which is the only other alternative to two sided printing in one pass through the press. These advantages can be found in product quality, a cleaner environment, and in economics. This development program is still in progress with efforts now directed towards adapting EB ink technology to the latest developments in intaglio printing, i.e. aqueous cylinder wiping which requires EB inks to be water dispersable. Also the stability of materials in contact with EB inks is being investigated

  17. Electron beam curing of intaglio inks

    International Nuclear Information System (INIS)

    O'Brien, T.

    1985-01-01

    Press trials conducted by the U.S. Bureau of Engraving and Printing at the National Bank of Denmark clearly indicated the feasibility of Electron Beam (E.B.) curing for web intaglio printing . These trials, some at continuous press runs of up to six hours, gave positive results for virtually all our requirements including: print quality, press speeds, ability to print both sides of the web on one pass through a press, acceptable ink curing at one megarad or less, and minimum substrate deterioration or loss of moisture. In addition, these trials demonstrated many advantages over thermal curing which is the only other alternative to two sided printing in one pass through the press. These advantages can be found in product quality, a cleaner environment, and in economics. This development program is still in progress with efforts now directed towards adapting E.B. ink technology to the latest developments in intaglio printing, i.e. aqueous cylinder wiping which requires E.B. inks to be water dispersable. Also the stability of materials in contact with E.B. inks is being investigated. (author)

  18. Soft and probe lithography without ink transfer

    NARCIS (Netherlands)

    Huskens, Jurriaan; Li, X.; Péter, M.; Reinhoudt, David

    2004-01-01

    Microcontact printing (mCP) and dip-pen nanolithography (DPN) are versatile techniques for the creation of patterned surfaces. They commonly employ the transfer of an ink (e.g. a thiol) onto a surface (e.g. a gold-coated substrate) thus forming a self-assembled monolayer (SAM). Resolution of these

  19. Analysis of iron gall inks by PIXE

    Energy Technology Data Exchange (ETDEWEB)

    Budnar, Milos [Jozef Stefan Institute, Jamova 39, p.p. 3000, SI-1001 Ljubljana (Slovenia)]. E-mail: milos.budnar@ijs.si; Ursic, Mitja [Jozef Stefan Institute, Jamova 39, p.p. 3000, SI-1001 Ljubljana (Slovenia); Simcic, Jure [Jozef Stefan Institute, Jamova 39, p.p. 3000, SI-1001 Ljubljana (Slovenia); Pelicon, Primoz [Jozef Stefan Institute, Jamova 39, p.p. 3000, SI-1001 Ljubljana (Slovenia); Kolar, Jana [National University Library, Turjaska 1, SI-1000 Ljubljana (Slovenia); Selih, Vid Simon [University of Ljubljana, Faculty of Chemistry and Chemical Technology, Askerceva 5, SI-1000 Ljubljana (Slovenia); Strlic, Matija [University of Ljubljana, Faculty of Chemistry and Chemical Technology, Askerceva 5, SI-1000 Ljubljana (Slovenia)

    2006-02-15

    Micro- or non-destructive analytical approach is an imperative when analysing historical artefacts. Due to its practically non-destructive character, proton induced X-ray spectrometry (PIXE) has become a method of choice for the study of historical documents. In the present paper, use of in-air PIXE method for analysis of iron gall inks applied at handwriting of documents is evaluated. The errors arising from the non-uniform ink deposit, proton penetration depth and size of the proton beam versus width of ink lines, effects of surface roughness, as well as the importance of the PIXE set-up geometry on the accuracy of the results are discussed. It follows that the main problems can be attributed to the fact that PIXE is a surface technique and that the analysis is limited to a small amount of material, while ink deposit on the paper is usually non-uniform in depth as well as on the paper surface. Despite possible systematic uncertainties when applying the PIXE method, good correlation between determinations obtained by PIXE and atomic absorption spectroscopy (AAS) on model samples clearly demonstrate that the errors are well within a reasonable limit of a few percents.

  20. Analysis of iron gall inks by PIXE

    International Nuclear Information System (INIS)

    Budnar, Milos; Ursic, Mitja; Simcic, Jure; Pelicon, Primoz; Kolar, Jana; Selih, Vid Simon; Strlic, Matija

    2006-01-01

    Micro- or non-destructive analytical approach is an imperative when analysing historical artefacts. Due to its practically non-destructive character, proton induced X-ray spectrometry (PIXE) has become a method of choice for the study of historical documents. In the present paper, use of in-air PIXE method for analysis of iron gall inks applied at handwriting of documents is evaluated. The errors arising from the non-uniform ink deposit, proton penetration depth and size of the proton beam versus width of ink lines, effects of surface roughness, as well as the importance of the PIXE set-up geometry on the accuracy of the results are discussed. It follows that the main problems can be attributed to the fact that PIXE is a surface technique and that the analysis is limited to a small amount of material, while ink deposit on the paper is usually non-uniform in depth as well as on the paper surface. Despite possible systematic uncertainties when applying the PIXE method, good correlation between determinations obtained by PIXE and atomic absorption spectroscopy (AAS) on model samples clearly demonstrate that the errors are well within a reasonable limit of a few percents

  1. NON-AQUEOUS PIGMENTED INKJET INKS

    NARCIS (Netherlands)

    DEROOVER, GEERT; Bernaerts, Katrien; HOOGMARTENS, IVAN

    2010-01-01

    A non-aqueous inkjet ink includes a benzimidazolone pigment and a polymeric dispersant according to Formula (I): wherein, T represents hydrogen or a polymerization terminating group; Z represents the residue of polyethyleneimine having a number-average molecular weight of at least 100; A represents

  2. Non-aqueous pigmented inkjet inks

    NARCIS (Netherlands)

    HOOGMARTENS, IVAN; Bernaerts, Katrien; DEROOVER, GEERT

    2008-01-01

    A non-aqueous inkjet ink comprising C.I. Pigment Yellow 150 and a polymeric dispersant according to Formula (I): wherein, T represents hydrogen or a polymerization terminating group; Z represents the residue of polyethyleneimine having a number-average molecular weight of at least 100; A represents

  3. Direct laser printing using viscous printer's ink

    International Nuclear Information System (INIS)

    Nasibov, A S; Bagramov, V G; Berezhnoi, K V

    2006-01-01

    The results of experiments on direct laser printing using viscous printer's ink with the help of a copper vapour laser (CVL)-based device are presented. The highly reflecting CVL cavity mirror was replaced by a spatial mirror modulator (SMM). Viscous printer's ink was used for printing. A pressure pulse produced at the boundary (on which an intensified and diminished image of the SMM was projected) between the ink and a transparency was used for transferring the ink to the plastic card. It was shown that the use of a CVL allowed a maximum printing speed of ∼80 cm 2 s -1 , a resolution of 625 dpi and up to 15 gradations. The dependence of the emission intensity of the element being projected (pixel) on its diameter is studied. It is shown that an increase in the brightness of this element with decreasing its size is caused by the summation of the laser and amplified radiation. (laser applications and other topics in quantum electronics)

  4. A randomized control trial evaluating fluorescent ink versus dark ink tattoos for breast radiotherapy.

    Science.gov (United States)

    Landeg, Steven J; Kirby, Anna M; Lee, Steven F; Bartlett, Freddie; Titmarsh, Kumud; Donovan, Ellen; Griffin, Clare L; Gothard, Lone; Locke, Imogen; McNair, Helen A

    2016-12-01

    The purpose of this UK study was to evaluate interfraction reproducibility and body image score when using ultraviolet (UV) tattoos (not visible in ambient lighting) for external references during breast/chest wall radiotherapy and compare with conventional dark ink. In this non-blinded, single-centre, parallel group, randomized control trial, patients were allocated to receive either conventional dark ink or UV ink tattoos using computer-generated random blocks. Participant assignment was not masked. Systematic (∑) and random (σ) setup errors were determined using electronic portal images. Body image questionnaires were completed at pre-treatment, 1 month and 6 months to determine the impact of tattoo type on body image. The primary end point was to determine that UV tattoo random error (σ setup ) was no less accurate than with conventional dark ink tattoos, i.e. tattoos. 45 patients completed treatment (UV: n = 23, dark: n = 22). σ setup for the UV tattoo group was tattoo group compared with the dark ink group at 1 month [56% (13/23) vs 14% (3/22), respectively] and 6 months [52% (11/21) vs 38% (8/21), respectively]. UV tattoos were associated with interfraction setup reproducibility comparable with conventional dark ink. Patients reported a more favourable change in body image score up to 6 months following treatment. Advances in knowledge: This study is the first to evaluate UV tattoo external references in a randomized control trial.

  5. Enhanced dispersibility and dispersion stability of dodecylamine-protected silver nanoparticles by dodecanethiol for ink-jet conductive inks

    International Nuclear Information System (INIS)

    Zhou, Xueqin; Li, Wei; Wu, Meilan; Tang, Shen; Liu, Dongzhi

    2014-01-01

    This work studied dodecylamine-protected silver nanoparticles modified by a small amount of dodecanethiol as the co-protective agent. Contents of the dodecanethiol and the protective agent capping on the surface of silver nanoparticles were analyzed using the method of oxygen flask combustion and a thermogravimetric analysis instrument. Results of electrical property determination and transmission electron microscopy indicate that certain amount of capping dodecanethiol can slow down the spontaneous sintering process of silver nanoparticles. When capping DDT content of silver nanoparticles is 1.70 wt%, 10 wt% suspensions are stable under −18 °C and can be stored stably at room temperature as long as 120 days. Furthermore, the silver nanoparticle concentration could be increased to 20 wt% with a stable storage time of 60 days at room temperature. Finally, stable polymer-free conductive inks with the silver nanoparticle concentration of 20 wt% were produced to fabricate patterns by ink-jet printing. The resistivity of the PI-supported patterns having been annealed at 130 °C for 10 min is 7.2 μΩ cm.

  6. Fabrication of porous zirconia using filter paper template

    International Nuclear Information System (INIS)

    Deng Yuhua; Wei Pan

    2005-01-01

    In this work, porous zirconia ceramic was synthesized using filter papers as a template. Special attention is paid to whether the structural of the filter paper can be transferred to the zirconia structure. Microstructure of so synthesized porous zirconia was observed with SEM and the phase was determined by XRD. The surface area and the pore were investigated with an automatic volumetric sorption analyzer. It has been found that the morphology of the template transmit to the porous zirconia quite well. (orig.)

  7. Tattoo ink nanoparticles in skin tissue and fibroblasts.

    Science.gov (United States)

    Grant, Colin A; Twigg, Peter C; Baker, Richard; Tobin, Desmond J

    2015-01-01

    Tattooing has long been practised in various societies all around the world and is becoming increasingly common and widespread in the West. Tattoo ink suspensions unquestionably contain pigments composed of nanoparticles, i.e., particles of sub-100 nm dimensions. It is widely acknowledged that nanoparticles have higher levels of chemical activity than their larger particle equivalents. However, assessment of the toxicity of tattoo inks has been the subject of little research and ink manufacturers are not obliged to disclose the exact composition of their products. This study examines tattoo ink particles in two fundamental skin components at the nanometre level. We use atomic force microscopy and light microscopy to examine cryosections of tattooed skin, exploring the collagen fibril networks in the dermis that contain ink nanoparticles. Further, we culture fibroblasts in diluted tattoo ink to explore both the immediate impact of ink pigment on cell viability and also to observe the interaction between particles and the cells.

  8. PIXE analysis of Italian ink drawings of the XVI century

    International Nuclear Information System (INIS)

    Zucchiatti, A.; Climent-Font, A.; Enguita, O.; Fernandez-Jimenez, M.T.; Finaldi, G.; Garrido, C.; Matillas, J.M.

    2005-01-01

    The composition of inks in a group of 24 drawings of ten XVI century Italian painters, has been determined by PIXE at the external micro-beam line of the Centro de Micro Analisis de Materiales of the Universidad Autonoma de Madrid. Ink elemental thicknesses have been determined by comparison with a set of certified thin standards. A comprehensive comparison of inks has also been performed by renormalisation of spectra and definition of an ink-to-ink distance. The elemental compositions and the ink-to-ink distances give consistent results that are generally in line with the appearance of the drawings and add relevant instrumental information to the stylistic observation, revealing for example the presence of retouches and additions in different parts of a drawing. Cluster analysis performed on a subgroup of 13 artefacts from the Genoese painter Luca Cambiaso and his school has revealed a partition that separates neatly the work of the master from that of his followers

  9. Tattoo ink nanoparticles in skin tissue and fibroblasts

    Directory of Open Access Journals (Sweden)

    Colin A. Grant

    2015-05-01

    Full Text Available Tattooing has long been practised in various societies all around the world and is becoming increasingly common and widespread in the West. Tattoo ink suspensions unquestionably contain pigments composed of nanoparticles, i.e., particles of sub-100 nm dimensions. It is widely acknowledged that nanoparticles have higher levels of chemical activity than their larger particle equivalents. However, assessment of the toxicity of tattoo inks has been the subject of little research and ink manufacturers are not obliged to disclose the exact composition of their products. This study examines tattoo ink particles in two fundamental skin components at the nanometre level. We use atomic force microscopy and light microscopy to examine cryosections of tattooed skin, exploring the collagen fibril networks in the dermis that contain ink nanoparticles. Further, we culture fibroblasts in diluted tattoo ink to explore both the immediate impact of ink pigment on cell viability and also to observe the interaction between particles and the cells.

  10. Rare earth taggants in-printing ink - its potential in forensic applications

    International Nuclear Information System (INIS)

    Joseph, Daisy; Chodhury, R.K.; Maind, Sandip

    2011-01-01

    Proton Induced X-ray Emission (PIXE) and Energy Dispersive X-ray Fluorescence (EDXRF) techniques were used for elemental characterization of offset printing ink tagged with rare-earth taggants. The offset printing ink was tagged with rare-earth (La, Pr, Nd, Sm, Eu and Gd) thenoyltrifluoroacetonate chelates at about 1000-ppm level for each element separately. Small aliquots (approximately 20 mg) of tagged inks were coated on paper supports in the form of small circles having diameter 10-15 mm each and then analyzed. In the case of PIXE, a proton beam of energy 4 MeV and in the case of EDXRF a radioisotope source of 241 Am (100 mCi) was used to excite the samples. The PIXE analysis showed well-resolved rare-earth LX-rays and EDXRF analysis showed the K X-rays of rare earths. The aim of this study is to see the efficacy of homogeneous mixing of inorganic taggants in offset printing ink with the objective to establish linear relation of intensity (signal) against concentrations/ amounts of taggant(s) and to derive the minimum detection limit, by EDXRF and PIXE. The feasibility study of determination of rare-earth elements in offset printing ink tagged with rare-earth thenoyltrifluoroacetonates was examined. In the present study, we have used the facility of Proton Induced X-ray Emission (PIXE) and Energy Dispersive X-ray Fluorescence (EDXRF) technique for identification of rare earths in tagged printing ink on paper support. Satisfactory results to identify and quantify the taggants were achieved. (author)

  11. Biomedical implementation of liquid metal ink as drawable ECG electrode and skin circuit.

    Directory of Open Access Journals (Sweden)

    Yang Yu

    Full Text Available BACKGROUND: Conventional ways of making bio-electrodes are generally complicated, expensive and unconformable. Here we describe for the first time the method of applying Ga-based liquid metal ink as drawable electrocardiogram (ECG electrodes. Such material owns unique merits in both liquid phase conformability and high electrical conductivity, which provides flexible ways for making electrical circuits on skin surface and a prospective substitution of conventional rigid printed circuit boards (PCBs. METHODS: Fundamental measurements of impedance and polarization voltage of the liquid metal ink were carried out to evaluate its basic electrical properties. Conceptual experiments were performed to draw the alloy as bio-electrodes to acquire ECG signals from both rabbit and human via a wireless module developed on the mobile phone. Further, a typical electrical circuit was drawn in the palm with the ink to demonstrate its potential of implementing more sophisticated skin circuits. RESULTS: With an oxide concentration of 0.34%, the resistivity of the liquid metal ink was measured as 44.1 µΩ·cm with quite low reactance in the form of straight line. Its peak polarization voltage with the physiological saline was detected as -0.73 V. The quality of ECG wave detected from the liquid metal electrodes was found as good as that of conventional electrodes, from both rabbit and human experiments. In addition, the circuit drawn with the liquid metal ink in the palm also runs efficiently. When the loop was switched on, all the light emitting diodes (LEDs were lit and emitted colorful lights. CONCLUSIONS: The liquid metal ink promises unique printable electrical properties as both bio-electrodes and electrical wires. The implemented ECG measurement on biological surface and the successfully run skin circuit demonstrated the conformability and attachment of the liquid metal. The present method is expected to innovate future physiological measurement and

  12. Work Function and Conductivity of Inkjet-Printed Silver Layers: Effect of Inks and Post-treatments

    Science.gov (United States)

    Mitra, Dana; Mitra, Kalyan Yoti; Dzhagan, Volodymyr; Pillai, Nikhil; Zahn, Dietrich R. T.; Baumann, Reinhard R.

    2018-03-01

    The electronic properties of a printed layer are influenced by a number of factors, including the nature of the ink (nanoparticle- or solution-based), ink composition (solvents, additives, concentration), and post-treatment technologies, especially sintering. One of the major challenges in the field of printed electronics is achieving the desired performance, for example, in terms of conductivity, resistivity, or work function (WF). This work investigates the dependence of sheet resistance and WF on various sintering methodologies. Four different silver nanoparticle inks were inkjet-printed on a flexible polymeric foil and post-treated by thermal sintering (in an oven) or novel sintering processes using infrared or intense pulsed light. The surfaces of the printed and sintered layers were investigated optically, and various inhomogeneities in the layer surface were observed, varying from a smooth to a highly rough appearance with ring-shaped drying structures. An analysis of the sheet resistance revealed notable variation among the various inks and sintering methodologies used. Here, for the very first time, WF is measured and evaluated as a function of sintering methodology and silver ink, and the respective layer formation characteristics realized with the inkjet printing technology. The WF values obtained by ultraviolet photoemission show a similar spread and allow unambiguous trends to be tracked with respect to the type of ink and sintering method used. The values of the WF obtained range from 3.7 eV to 4.3 eV, approaching the reported bulk values of 4.3-4.7 eV. The various silver inks resulted in different WFs when the same sintering method was used, while the same silver ink resulted in different WFs when various sintering methods were applied. Therefore, it is believed that the WF can be tuned over a broad range in a controlled manner to satisfy electronic device requirements.

  13. Effect of an experimental zirconia-silica coating technique on micro tensile bond strength of zirconia in different priming conditions

    NARCIS (Netherlands)

    Chen, C.; Kleverlaan, C.J.; Feilzer, A.J.

    2012-01-01

    Objectives This study aimed to evaluate the adhesive properties of a MDP-containing resin cement to a colored zirconia ceramic, using an experimental zirconia-silica coating technique with different priming conditions. Methods 18 zirconia ceramic discs (Cercon base colored) were divided into two

  14. Anelasticity and strength in zirconia ceramics

    International Nuclear Information System (INIS)

    Matsuzawa, M.; Horibe, S.; Sakai, J.

    2005-01-01

    Non-elastic strain behavior was investigated for several different zirconia ceramics and a possible mechanism for anelasticity was discussed. Anelastic strain was detected in zirconia ceramics irrespective of the crystallographic phase and its productivity depended on the particular kind of dopant additive. It was found that the anelastic properties could be significantly influenced by the level of oxygen vacancy in the matrix, and that the anelastic strain might be produced by a light shift of ionic species. In order to investigate the effect of anelasticity on mechanical properties on zirconia ceramics, the tensile strength was investigated for a wide range of strain rates. The obviously unique strain rate dependence was observed only in the materials having anelastic properties. It was assumed that anelasticity could be efficient at improving the tensile strength. (orig.)

  15. Microstructural evolution of alumina-zirconia nanocomposites

    International Nuclear Information System (INIS)

    Ojaimi, C.L.; Chinelatto, A.S.A.; Chinelatto, A.L.; Pallone, E.M.J.A.

    2012-01-01

    Ceramic materials have limited use due to their brittleness. The inclusion of nanosized particles in a ceramic matrix, which are called nanocomposites, and ceramic processing control by controlling the grain size and densification can aid in obtaining ceramic products of greater strength and toughness. Studies showed that the zirconia nano inclusions in the matrix of alumina favors an increase in mechanical properties by inhibiting the grain growth of the matrix and not by the mechanism of the transformation toughening phase of zirconia. In this work, the microstructural evolution of alumina nanocomposites containing 15% by volume of nanometric zirconia was studied. From the results it was possible to understand the sintering process of these nanocomposites. (author)

  16. Non-Newtonian ink transfer in gravure-offset printing

    International Nuclear Information System (INIS)

    Ghadiri, Fatemeh; Ahmed, Dewan Hasan; Sung, Hyung Jin; Shirani, Ebrahim

    2011-01-01

    The inks used in gravure-offset printing are non-Newtonian fluids with higher viscosities and lower surface tensions than Newtonian fluids. This paper examines the transfer of a non-Newtonian ink between a flat plate and a groove when the plate is moved upward with a constant velocity while the groove is held fixed. Numerical simulations were carried out with the Carreau model to explore the behavior of this non-Newtonian ink in gravure-offset printing. The volume of fluid (VOF) method was implemented to capture the interface during the ink transfer process. The effects of varying the contact angle of the ink on the flat plate and groove walls and geometrical parameters such as the groove angle and the groove depth on the breakup time of the liquid filament that forms between the plate and the groove and the ink transfer ratio were determined. Our results indicate that increasing the groove contact angle and decreasing the flat plate contact angle enhance the ink transfer ratio and the breakup time. However, increasing the groove depth and the groove angle decreases the transfer ratio and the breakup time. By optimizing these parameters, it is possible to achieve an ink transfer from the groove to the flat plate of approximately 92%. Moreover, the initial width and the vertical velocity of the neck of the ink filament have significant influences on the ink transfer ratio and the breakup time.

  17. Inkjet printed electronics using copper nanoparticle ink

    OpenAIRE

    Kang, Jin Sung; Kim, Hak Sung; Ryu, Jongeun; Thomas Hahn, H.; Jang, Seonhee; Joung, Jae Woo

    2010-01-01

    Inkjet printing of electrode using copper nanoparticle ink is presented. Electrode was printed on a flexible glass epoxy composite substrate using drop on demand piezoelectric dispenser and was sintered at 200 °C of low temperature in N2 gas condition. The printed electrodes were made with various widths and thickness. In order to control the thickness of the printed electrode, number of printing was varied. Resistivity of printed electrode was calculated from the cross-sectional area measure...

  18. Advanced verification methods for OVI security ink

    Science.gov (United States)

    Coombs, Paul G.; McCaffery, Shaun F.; Markantes, Tom

    2006-02-01

    OVI security ink +, incorporating OVP security pigment* microflakes, enjoys a history of effective document protection. This security feature provides not only first-line recognition by the person on the street, but also facilitates machine-readability. This paper explores the evolution of OVI reader technology from proof-of-concept to miniaturization. Three different instruments have been built to advance the technology of OVI machine verification. A bench-top unit has been constructed which allows users to automatically verify a multitude of different banknotes and OVI images. In addition, high speed modules were fabricated and tested in a state of the art banknote sorting machine. Both units demonstrate the ability of modern optical components to illuminate and collect light reflected from the interference platelets within OVI ink. Electronic hardware and software convert and process the optical information in milliseconds to accurately determine the authenticity of the security feature. Most recently, OVI ink verification hardware has been miniaturized and simplified providing yet another platform for counterfeit protection. These latest devices provide a tool for store clerks and bank tellers to unambiguously determine the validity of banknotes in the time period it takes the cash drawer to be opened.

  19. Mesoporous yttria-zirconia and metal-yttria-zirconia solid solutions for fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Mamak, M.; Coombs, N.; Ozin, G. [Toronto Univ., ON (Canada). Dept. of Chemistry

    2000-02-03

    A new class of binary mesoporous yttria-zirconia (YZ) and ternary mesoporous metal-YZ materials (M = electroactive Ni/Pt) is presented here that displays the highest surface area of any known form of yttria-stabilized zirconia. These mesoporous materials form as solid solutions and retain their structural integrity to 800 C, which bodes well for their possible utilization in fuel cells. (orig.)

  20. Using glass-graded zirconia to increase delamination growth resistance in porcelain/zirconia dental structures.

    Science.gov (United States)

    Chai, Herzl; Mieleszko, Adam J; Chu, Stephen J; Zhang, Yu

    2018-01-01

    Porcelain fused to zirconia (PFZ) restorations are widely used in prosthetic dentistry. However, their tendency to delaminate along the P/Z interface remains a practical problem so that assessing and improving the interfacial strength are important design aspects. This work examines the effect of modifying the zirconia veneering surface with an in-house felspathic glass on the interfacial fracture resistance of fused P/Z. Three material systems are studied: porcelain fused to zirconia (control) and porcelain fused to glass-graded zirconia with and without the presence of a glass interlayer. The specimens were loaded in a four-point-bend fixture with the porcelain veneer in tension. The evolution of damage is followed with the aid of a video camera. The interfacial fracture energy G C was determined with the aid of a FEA, taking into account the stress shielding effects due to the presence of adjacent channel cracks. Similarly to a previous study on PFZ specimens, the fracture sequence consisted of unstable growth of channel cracks in the veneer followed by stable cracking along the P/Z interface. However, the value of GC for the graded zirconia was approximately 3 times that of the control zirconia, which is due to the good adhesion between porcelain and the glass network structure on the zirconia surface. Combined with its improved bonding to resin-based cements, increased resistance to surface damage and good esthetic quality, graded zirconia emerges as a viable material concept for dental restorations. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  1. Thermal bubble inkjet printing of water-based graphene oxide and graphene inks on heated substrate

    Science.gov (United States)

    Huang, Simin; Shen, Ruoxi; Qian, Bo; Li, Lingying; Wang, Wenhao; Lin, Guanghui; Zhang, Xiaofei; Li, Peng; Xie, Yonglin

    2018-04-01

    Stable-jetting water-based graphene oxide (GO) and graphene (GR) inks without any surfactant or stabilizer are prepared from an unstable-jetting water-based starting solvent, with many thermal bubble inkjet satellite drops, by simply increasing the material concentration. The concentration-dependent thermal bubble inkjet droplet generation process is studied in detail. To overcome the low concentration properties of water-based thermal bubble inkjet inks, the substrate temperature is tuned below 60 °C to achieve high-quality print lines. Due to the difference in hydrophilicity and hydrophobicity of the 2D materials, the printed GO lines show a different forming mechanism from that of the GR lines. The printed GO lines are reduced by thermal annealing and by ascorbic acid, respectively. The reduced GO lines exhibit electrical conductivity of the same order of magnitude as that of the GR lines.

  2. Microstructure and thermal stability of Fe, Ti and Ag implanted Yttria-stabilized zirconia

    NARCIS (Netherlands)

    van Hassel, B.A.; van Hassel, B.A.; Burggraaf, Anthonie; Burggraaf, A.J.

    1991-01-01

    Yttria-stabilized zirconia (YSZ) was implanted with 15 keV Fe or Ti ions up to a dose of 8×1016 at cm−2. The resulting “dopant” concentrations exceeded the concentrations corresponding to the equilibrium solid solubility of Fe2O3 or TiO2 in YSZ. During oxidation in air at 400° C, the Fe and Ti

  3. Non-destructive study of iron gall inks in manuscripts

    Science.gov (United States)

    Duh, Jelena; Krstić, Dragica; Desnica, Vladan; Fazinić, Stjepko

    2018-02-01

    The aim of this research is to establish an effective procedure of iron gall ink characterization using complementary non-destructive methods. By this, it is possible to better understand correlation of chemical composition of the inks and the state of preservation of iron gall ink manuscripts, as well as the effects of conservation treatment performed upon them. This study was undertaken on a bound 16th century manuscript comprised of different types of paper and ink from the National and University Library in Zagreb. Analytical methods used included Particle Induced X-ray Emission (PIXE) and X-ray Fluorescence (XRF). Paper fibers were identified by optical microscopy and the degradation state, as well as ink differentiation, transit metal migrations and detection of stains, with ultraviolet (UV) and infrared (IR) photography. The techniques applied on original writing materials gave important information about paper and ink composition, its preservation state and efficiency of conservation treatment performed upon them.

  4. Graphene Ink Film Based Electrochemical Detector for Paracetamol Analysis

    Directory of Open Access Journals (Sweden)

    Li Fu

    2018-01-01

    Full Text Available Graphene ink is a commercialized product in the graphene industry with promising potential application in electronic device design. However, the limitation of the graphene ink is its low electronic performance due to the ink preparation protocol. In this work, we proposed a simple post-treatment of graphene ink coating via electrochemical oxidation. The electronic conductivity of the graphene ink coating was enhanced as expected after the treatment. The proposed electrochemical oxidation treatment also exposes the defects of graphene and triggered an electrocatalytic reaction during the sensing of paracetamol (PA. The overpotential of redox is much lower than conventional PA redox potential, which is favorable for avoiding the interference species. Under optimum conditions, the graphene ink-based electrochemical sensor could linearly detect PA from 10 to 500 micro molar (μM, with a limit of detection of 2.7 μM.

  5. SiOx Ink-Repellent Layer Deposited by Radio Frequency (RF) Plasmas in Continuous Wave and Pulse Mode

    International Nuclear Information System (INIS)

    Chen Qiang; Fu Yabo; Pang Hua; Zhang Yuefei; Zhang Guangqiu

    2007-01-01

    Low surface energy layers, proposed application for non-water printing in computer to plate (CTP) technology, are deposited in both continuous wave and pulse radio frequency (13.56 MHz) plasma with hexamethyldisiloxane (HMDSO) as precursor. It is found that the plasma mode dominates the polymer growth rate and the surface composition. Derived from the spectra of X-ray photoelectron spectroscopy (XPS) and combined with printable test it is concluded that concentration of Si in coatings plays an important role for the ink printability and the ink does not adhere on the surface with high silicon concentration

  6. A comprehensive evaluation of the toxicology of monogram inks added to experimental cigarettes.

    Science.gov (United States)

    Smith, Donna C; Wiecinski, Paige N; Coggins, Christopher R E; Banty, Tamara H; Oldham, Michael J

    2013-01-01

    Cigarettes often have a small identifying mark (monogram) printed either on the cigarette paper toward the filter end of the cigarette or on the tipping paper. A battery of tests was used to compare the toxicology of mainstream smoke from experimental cigarettes manufactured with different monogram inks. Cigarettes with different concentrations of different pigments were compared with cigarettes without ink, and with a control ink. Smoke from each of the experimental cigarettes was evaluated using analytical chemistry and in vitro bacterial mutagenicity (Salmonella, five strains, ± S9) and cytotoxicity (neutral red uptake) assays. No differences were observed between experimental cigarettes printed with three different pigment loads of iron oxide-based Black pigment and non-printed cigarettes. In general, no dose response was observed. However, increases in certain smoke constituents were found to correlate with Pigment Yellow 14 (also known as benzidine yellow) and Pigment Blue 15 (copper phthalocyanine). Increases in bacterial mutagenicity were observed for high-level print of Pigment Yellow 14 in TA98 and TA1537 and the high-level print of Pigment Blue 15 in TA98. In vitro cytotoxicity of mainstream smoke was unaffected by the presence of monogram ink on cigarettes. Statistically significant dose-responsive constituent changes and an increase in mutagenicity were observed with inclusion of Pigment Yellow 14 and Pigment Blue 15. Other pigments showed minimal toxicological activity.

  7. Antibacterial Activity of Melanin from Cuttlefish and Squid Ink

    OpenAIRE

    Yuspihana Fitrial; Iin Khusnul Khotimah

    2017-01-01

    Marine environment comprises of many organism which are known to posses bioactive compound as a common means of self-defense or for the protection of eggs and embryos. Class Cephalopods (such as squidand cuttlefish) are notable for their defences, such as jetting escape movements, changes in colouration, toxic venom and inking.This study aims to compare the antibacterial activity of melanin from cuttlefish ink (Sepia sp.) with squid ink (Loligo sp.) against E. coli. Extraction and purificatio...

  8. Zirconia-based colors for ceramic glazes

    International Nuclear Information System (INIS)

    Eppler, R.A.

    1977-01-01

    The history of color development for use in ceramic glazes is outlined. The most significant modern development is based on zirconia and zircon. These materials have gained increasing acceptance in the industry since their introduction in the late 1950's and early 1960's, due to their superior stability during firing of the glaze

  9. Zirconia toughened ceramics for heat engine applications

    International Nuclear Information System (INIS)

    Rossi, G.A.; Blum, J.B.; Manwiller, K.E.; Knapp, C.E.

    1986-01-01

    Three classes of zirconia toughened ceramics (ZTC) were studied, i.e. Mg-PSZ (MgO-partially stabilized zirconia), Y-TZP (Y/sub 2/O/sub 3/-tetragonal zirconia polycrystals) and ZTA (zirconia toughened alumina). The main objective was to improve the high temperature strength and toughness, which are not satisfactory in the ''state of the art'' ZTC materials. Powders prepared by melting/rapid solidification and by chemical routes were used. The green parts were made by both dry and wet shape forming methods. Fine grained Mg-PSZ ceramics with unique microstructures were produced using the rapidly solidified powders. The Y-TZP materials were improved mainly through microstructure control and by addition of alpha alumina as a dispersed phase. Preliminary results on ZTA ceramics made with the rapidly solidified powders were also obtained. It is concluded that the Al/sub 2/O/sub 3//Y-TZP composites offer a good chance of meeting the program objectives

  10. Peculiarities of structural transformations in zirconia nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Vasilevskaya, A., E-mail: a.k.vasilevskaya@gmail.com [Technical University, Saint-Petersburg State Institute of Technology (Russian Federation); Almjasheva, O. V. [Saint-Petersburg Electrotechnical University “LETI” (Russian Federation); Gusarov, V. V. [Ioffe Physical-Technical Institute of the Russian Academy of Sciences (Russian Federation)

    2016-07-15

    The transitions of metastable tetragonal phase as well as high-temperature tetragonal phase into the low-temperature monoclinic phase upon heating and cooling were thoroughly studied in zirconia nanoparticles. High-temperature X-ray diffraction, thermal analysis and Raman spectroscopy were used to provide the systematic approach to the investigation of zirconia nanoparticles thermal behavior. A phase transformation sequence in the ZrO{sub 2}–H{sub 2}O system was determined, and the mechanisms of tetragonal-to-monoclinic transition upon heating and cooling were suggested. Here, the phenomenon was found and described, which was determined as “self-powdering” of nanoparticles occurring during structural transition. This phenomenon was observed by in situ investigation of the evolution of crystalline nanoparticles from amorphous zirconium hydroxide during thermal treatment in air. The tetragonal-to-monoclinic phase transition, induced by cooling from the temperature of equilibrium of tetragonal zirconia (i.e., above 1170 °C), is accompanied by a significant crystallite size decrease (with corresponding 3–4 times decrease of crystallite volume). The experimental results facilitate applications of zirconia nanoparticles to obtain high-performance nanopowders for nanoceramics.

  11. Densification of zirconia-hematite nanopowders

    NARCIS (Netherlands)

    Raming, T.P.; Winnubst, Aloysius J.A.; van Zyl, W.E.; Verweij, H.

    2003-01-01

    The densification of dual-phase yttria-doped tetragonal zirconia polycrystals (Y-TZP) and -Fe2O3 (hematite) composite powders is described. Different powder synthesis methods, different forms of dry compaction processes, and two sinter methods (pressureless sintering and sinterforging) were

  12. Tintas Ink-Jet para Decoracion 3D

    Directory of Open Access Journals (Sweden)

    Spain S.A., Ferro

    2011-04-01

    Full Text Available A new set of different ink-jet inks to be apply as a 3D object and extrafine layers to protect the decoration made by ink-jet technology. These new inks are obtained through the development of new frits based on monophasic crystal vitro structures that allows ceramic effects obtained via digital decoration. The new inks improve the ability of application by ink-jet heads in order to achieve aesthetics and decorative effects than those obtained with conventional decoration.

    Se han desarrollado un conjunto de diferentes tintas ink-jet, para aplicar como objeto 3D y capas extrafinas con el fin de proteger la decoración realizada mediante tecnología ink-jet. Estas nuevas tintas se obtienen a través del desarrollo de nuevas fritas basadas en estructuras vitro cristalinas monofásicas que permiten obtener efectos cerámicos mediante decoración digital. Las nuevas tintas mejoran la capacidad de aplicación mediante cabezales ink-jet con el fin de conseguir efectos estéticos y decorativos superiores a los obtenidos con la decoración convencional.

  13. Problems with ink skin markings for radiation field setups

    International Nuclear Information System (INIS)

    Endoh, Masaru; Saeki, Mituaki; Ishida, Yusei

    1982-01-01

    Ink skin markings are used in radiation therapy to aid in reproduction of treatment field setups or to indelibly outline field markings or tumors. We reported two cases of indelible ink skin for radiation field septa with minimal discomfort and dermatitis have been experienced for 6 months and above since end of radiotherapy. These indelible ink skin markings look like tattoo that will be big problems in the case of young female. We improved these problems by using of 10 percent silver nitrate instead of habitual skin ink. (author)

  14. New Yellow Synergist for Stable Pigment Dispersion of Inkjet Ink.

    Science.gov (United States)

    Song, Gihyun; Lee, Hayoon; Jung, Hyocheol; Kang, Seokwoo; Park, Jongwook

    2018-02-01

    Minimizing ink droplet and self-dispersed pigment mixture are becoming hot issues for high resolution of inkjet printing. New synergist including sulfonic acid group of PY-74 was suggested and synthesized. Pigment itself did not show water solubility but new synergist, SY-11 exhibited good solubility in water and organic solvents such as DMSO and DMF. When aqueous pigment ink was prepared with SY-11, storage stability of the ink has been remained for 7 days under periodically repeated heating and cooling conditions. Particle size of formulated ink was around 150 nm.

  15. Rapid laser sintering of metal nano-particles inks.

    Science.gov (United States)

    Ermak, Oleg; Zenou, Michael; Toker, Gil Bernstein; Ankri, Jonathan; Shacham-Diamand, Yosi; Kotler, Zvi

    2016-09-23

    Fast sintering is of importance in additive metallization processes and especially on sensitive substrates. This work explores the mechanisms which set limits to the laser sintering rate of metal nano-particle inks. A comparison of sintering behavior of three different ink compositions with laser exposure times from micro-seconds to seconds reveals the dominant factor to be the organic content (OC) in the ink. With a low OC silver ink, of 2% only, sintering time falls below 100 μs with resistivity <×4 bulk silver. Still shorter exposure times result in line delamination and deformation with a similar outcome when the OC is increased.

  16. Gas chromatography-mass spectrometry and high-performance liquid chromatography-diode array detection for dating of paper ink.

    Science.gov (United States)

    Díaz-Santana, Oscar; Vega-Moreno, Daura; Conde-Hardisson, Francisco

    2017-09-15

    An extraction and determination method is shown for the analysis of dyes and solvents present in two types of ballpoint pen inks that are deposited onto paper. Ink extracts are analysed using a combination of gas chromatography with mass spectrometry (GC-MS), and high-pressure liquid chromatography with photodiode array detection (HPLC-DAD), within a single sample extraction procedure. Seventeen solvents and thirteen dyes contained in two Montblanc ® inks (black and blue) were monitored for 45 months at monthly intervals, in order to determine variations in the concentrations of the compounds over time. We also studied the relative variations between different compounds and the generation of degradation products such as phenol. The concentration data obtained from these compounds during their exposure have been analysed and a multiple regression model is developed for each ink type that allows an estimate of the exposure time of the ink on paper with a maximum error of between 4 and 7 months. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. A short and long range study of mullite-zirconia-zircon composites

    Energy Technology Data Exchange (ETDEWEB)

    Rendtorff, Nicolas M.; Conconi, Maria S.; Aglietti, Esteban F. [Centro de Tecnologia de Recursos Minerales y Ceramica (CETMIC: CONICET-CIC) (Argentina); Chain, Cecilia Y.; Pasquevich, Alberto F. [Universidad Nacional de La Plata, Departamento de Fisica, IFLP, Facultad de Ciencias Exactas (Argentina); Rivas, Patricia C. [CONICET (Argentina); Martinez, Jorge A., E-mail: toto@fisica.unlp.edu.ar; Caracoche, Maria C. [Universidad Nacional de La Plata, Departamento de Fisica, IFLP, Facultad de Ciencias Exactas (Argentina)

    2010-06-15

    In the field of refractory materials, ceramics containing mullite-zirconia are the basis of those most used in the industry of glass and steel. It is known that the addition of zircon improves the behavior of the refractory used in service. Knowing that some mullite-zirconia composites properties as fracture strength and the elastic modulus E are associated with the material microstructure integrity, the eventual thermal decomposition of zircon into zirconia and silica could seriously alter the material elastic properties. In this paper the phase content of a series of mullite-zirconia-zircon (3Al{sub 2}O{sub 3}.2SiO{sub 2}-ZrO{sub 2}-ZrSiO{sub 4}) composites is determined at atomic level via perturbed angular correlations (PAC) and compared with that derived from the long range X-ray diffraction technique. PAC results on the as-prepared materials indicate that all nominal zircon is present and that it involves two types of nanoconfigurations, one of them describing aperiodic regions. The thermomechanical properties already reported for these materials could be related to the crystalline to aperiodic zircon concentrations ratio they exhibit.

  18. Preparation and antibacterial properties of hybrid-zirconia films with silver nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Azocar, Ignacio, E-mail: manuel.azocar@usach.cl [Departamento de Quimica de los Materiales, Facultad de Quimica y Biologia, Universidad de Santiago de Chile, USACH, Avenida Bernardo O' Higgins 3363, Casilla 40, Correo 33, Santiago (Chile); Vargas, Esteban [Facultad de Ingenieria, Departamento de Metalurgia, Universidad de Santiago de Chile, USACH (Chile); Duran, Nicole [Departamento de Quimica de los Materiales, Facultad de Quimica y Biologia, Universidad de Santiago de Chile, USACH, Avenida Bernardo O' Higgins 3363, Casilla 40, Correo 33, Santiago (Chile); Arrieta, Abel [Departamento de Biologia, Facultad de Quimica y Biologia, Universidad de Santiago de Chile, USACH (Chile); Gonzalez, Evelyn [Departamento de Quimica de los Materiales, Facultad de Quimica y Biologia, Universidad de Santiago de Chile, USACH, Avenida Bernardo O' Higgins 3363, Casilla 40, Correo 33, Santiago (Chile); Facultad de Ingenieria, Departamento de Metalurgia, Universidad de Santiago de Chile, USACH (Chile); Departamento de Biologia, Facultad de Quimica y Biologia, Universidad de Santiago de Chile, USACH (Chile); Departamento de Quimica Farmacologica y Toxicologica, Facultad de Ciencias Quimicas, Universidad de Chile, Sergio Livingstone Polhammer 1007, Santiago (Chile); and others

    2012-11-15

    The antimicrobial effect of incorporating silver nanoparticles (AgNps) into zirconia matrix-polyether glycol was studied. AgNps of 4-6 nm in size were synthesized using the inverse micelles method, and different doses of metallic nanoparticles were incorporated into zirconia-polyether glycol mixtures during the ageing procedure. Atomic force microscopy (AFM) of the modified hybrid film showed a homogenous distribution of 20-80 nm diameter AgNps, indicating agglomeration of these structures during film modification; such agglomerations were greater when increasing the dosage of the colloidal system. The AgNps-hybrid films showed higher antimicrobial activity against Gram-positive bacteria than for Gram-negative bacteria. Hybrid films prepared with dioctyl sodium sulfosuccinate (AOT) stabilized AgNps presented enhanced antibacterial activity compared to that obtained through the addition of a high AgNO{sub 3} concentration (0.3 wt%). -- Graphical abstract: Atomic Force Micrographs, top and cross section view, showing silver nanoparticles embedded in a zirconia-polyether glycol hybrid film. Highlights: Black-Right-Pointing-Pointer Antibacterial activity of films (zirconia-polyether glycol) modified with silver nanoparticles. Black-Right-Pointing-Pointer Biofilm formation is prevented. Black-Right-Pointing-Pointer High sensibility against gram positive bacteria.

  19. Digital decoration by continuous ink jet system for ceramic products based in water inks

    International Nuclear Information System (INIS)

    Colores Ceramicos, S. A.; Talleres Foro, S. L.

    2010-01-01

    A new continuous ink jet system for digital ceramic decoration using water based dispersed ceramic pigment has been developed, that increases drastically the sustainability of the process. During the development of this work, different equipment for any application and the consumables and design tools have been also developed. (Author)

  20. Chemical treatment and biomimetic coating evaluating in zirconia-alumina ceramics; Avaliacao de tratamentos quimicos e recobrimento biomimetico em ceramicas de alumina-zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Amanda Abati

    2007-07-01

    Ceramic materials, as alumina and zirconia have been explored along the years as biomaterials application. The bio inert nature has been stimulating the development of new alternatives, as chemical treatments to improve the biological application of these ceramics. The biomimetic process of bio inert ceramics for coating apatite is based on soaking the implant in a simulated body fluid, SBF, with ion concentrations nearly equal to those of human blood plasma. The bioactivity of the material is related with the formation of a layer constituted of hydroxyapatite low crystalline, similar to the biological apatite. The biocompatibility associated to the structural properties of the alumina and zirconia has been stimulating the clinical use of these materials, mainly in areas of larger mechanical requests, places not recommended for bioactive hydroxyapatite, for instance. In this work samples of alumina, zirconia doped with Yttria (3% mol) and composites of alumina and zirconia doped with Yttria (3% mol) were prepared by co-precipitation method, calcinate, sintered, chemically treated with solutions of acid phosphoric and sodium hydroxide and them immersed in 1.0 M and 1.5 M SBF. The calcinate powders were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), gas adsorption (BET) and laser diffraction. The XRD results indicate that the samples are low crystalline. It was observed for BET that the samples present high specific surface area. The results of laser diffraction and SEM showed that the powders are agglomerates. The sintered samples were analyzed by XRD, SEM and X-ray fluorescence (XRF). The phases quantified by Rietveld method were: cubic, tetragonal and monoclinic of the zirconia, besides the phase alpha of the alumina. The chemical treatment with phosphoric acid didn't present a tendency of larger apatite formation in relation to the samples no chemically treated. The treatment with sodium hydroxide provoked accentuated transformation

  1. A magnetic nano-particle ink for tunable microwave applications

    KAUST Repository

    Ghaffar, Farhan A.; Vaseem, Mohammad; Shamim, Atif

    2016-01-01

    fully printed multilayer fabrication process is demonstrated where the substrate is also realized through printing. A novel Fe2O3 based magnetic ink is used as a substrate while an in-house silver organo complex (SOC) ink is developed for metallic layers

  2. Preparation and evaluation of squid ink polysaccharide-chitosan as a wound-healing sponge.

    Science.gov (United States)

    Huang, Na; Lin, Jiali; Li, Sidong; Deng, Yifeng; Kong, Songzhi; Hong, Pengzhi; Yang, Ping; Liao, Mingneng; Hu, Zhang

    2018-01-01

    A new type of wound healing agent was developed using two marine biomaterials (squid ink polysaccharide and chitosan) as carriers and calcium chloride as an initiator for coagulation. Based on central composite design-response surface methodology, comprehensive evaluation of appearance quality for composite sponges and water absorbency were used as evaluation indices to identify the optimized preparation conditions and further evaluate the performance of the squid ink polysaccharide-chitosan sponge (SIP-CS). The optimized formulation of SIP-CS was as follows: chitosan concentration, 2.29%; squid ink polysaccharide concentration, 0.55%; and calcium chloride concentration, 2.82%, at a volume ratio of 15:5:2. SIP-CS was conducive to sticking on the wound, characterized by the spongy property, strong absorptivity, and tackiness. Rabbit ear arterial, hepatic, and femoral artery hemorrhage experiments indicated that, compared with chitosan dressings and absorbable gelatin, the hemostatic times were shorter and the bleeding volume was smaller. Furthermore, SIP-CS absorbed a large amount of hemocytes, leading to rapid hemostasis. The healing areas and wound pathological sections in scalded New Zealand rabbits indicated that SIP-CS promoted wound healing more rapidly than chitosan and better than commercially available burn cream. Thus, SIP-CS is a good wound healing agent for rapid hemostasis, promoting burn/scalded skin healing, and protecting from wound infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Superplastic flow of two-phase ceramics containing rigid inclusions-zirconia/mullite composites

    International Nuclear Information System (INIS)

    Yoon, C.K.; Chen, I.W.

    1990-01-01

    A continuum theory for non-newtonian flow of a two-phase composite containing rigid inclusions is presented. It predicts flow suppression by a factor of (1 - V) q , where V is the volume fraction of the rigid inclusion and q depends on the stress exponent and the inclusion shape. Stress concentrations in the rigid inclusion have also been evaluated. As the stress exponent increases, flow suppression is more pronounced even though stress concentration is less severe. To test this theory, superplastic flow of zirconia/mullite composites, in which zirconia is a soft, non-Newtonian super-plastic matrix and mullite is a rigid phase of various size, shape, and amount, is studied. The continuum theory is found to describe the two-phase superplastic flow reasonably well

  4. Surface Patterning Using Diazonium Ink Filled Nanopipette.

    Science.gov (United States)

    Zhou, Min; Yu, Yun; Blanchard, Pierre-Yves; Mirkin, Michael V

    2015-11-03

    Molecular grafting of diazonium is a widely employed surface modification technique. Local electrografting of this species is a promising approach to surface doping and related properties tailoring. The instability of diazonium cation complicates this process, so that this species was generated in situ in many reported studies. In this Article, we report the egress transfer of aryl diazonium cation across the liquid/liquid interface supported at the nanopipette tip that can be used for controlled delivery this species to the external aqueous phase for local substrate patterning. An aryl diazonium salt was prepared with weakly coordinating and lipophilic tetrakis(pentafluorophenyl)borate anion stable as a solid and soluble in low polarity media. The chemically stable solution of this salt in 1,2-dichloroethane can be used as "diazonium ink". The ink-filled nanopipette was employed as a tip in the scanning electrochemical microscope (SECM) for surface patterning with the spatial resolution controlled by the pipette orifice radius and a few nanometers film thickness. The submicrometer-size grafted spots produced on the HOPG surface were located and imaged with the atomic force microscope (AFM).

  5. A magnetic nano-particle ink for tunable microwave applications

    KAUST Repository

    Ghaffar, Farhan A.

    2016-12-19

    Inkjet printing or printing for realization of inexpensive and large area electronics has unearthed as an attractive fabrication technique. Though at present, mostly the metallic inks are printed on regular microwave substrates. In this paper, a fully printed multilayer fabrication process is demonstrated where the substrate is also realized through printing. A novel Fe2O3 based magnetic ink is used as a substrate while an in-house silver organo complex (SOC) ink is developed for metallic layers. Complete magnetostatic and microwave characterization of the ink is presented. At the end, a tunable patch antenna is shown as an application using the magnetic ink as the substrate. The antenna shows a tuning range of 12.5 % for a magnetic field strength of 3 kOe.

  6. The development of zirconia membrane oxygen separation technology

    International Nuclear Information System (INIS)

    Chiacchi, F.T.; Badwal, S.P.S.; Velizko, V.

    2000-01-01

    The oxygen separation technology based on ceramic membranes constructed from stabilised zirconia is currently under development for applications ranging from oxygen generation or air enrichment for medical use to control of oxygen concentration or oxygen removal from gas streams and enclosures for semiconductor, food packaging and process control instrumentation industries. The technology is based on a rugged tubular design with extensive thermal cycling capability. Several single and three tube devices have been operated for periods up to 5000h. An eight tube module, as a building block for larger scale oxygen production or removal devices, has been constructed and is being evaluated. In this paper, the construction of the device, oxygen generating capacity, life time tests and performance of the ceramic membrane device under development at CSIRO will be discussed. Copyright (2000) The Australian Ceramic Society

  7. Interaction of oxygen with zirconia surface

    International Nuclear Information System (INIS)

    Ivankiv, L.I.; Ketsman, I.V.

    1999-01-01

    The influence of surface heat treatment, electron (50-800) eV irradiation and UV (180-300) nM illumination of adsorption system on the state of oxygen adsorbed on zirconia surface have been investigated. On the basis of experimental results obtained by investigation of photon emission accompanying oxygen adsorption (AL) and TPD data existence of adsorption sites on the surface is suggested on which irreversible dissociative adsorption of oxygen occurs. These very sites are associated with emission processes Conclusion is made that the only type of adsorption sites connected with anion vacancy is present on zirconia surface and this is its charge state that determines the state of adsorbed oxygen. One of the important mechanisms by which the electron and UV photon excitation affects the adsorption interaction is the change of the charge state of the adsorption site

  8. Synthesis of nanosized powders of stabilized zirconia

    International Nuclear Information System (INIS)

    Takodoro, Sandra Kiyoko

    2000-01-01

    Zirconia solid solutions containing 3 mol % Yttria or 12 mol % ceria have been prepared by the coprecipitation technique followed by azeotropic distillation. The aim of this work is the synthesis of tetragonal zirconia polycrystals nanosized powders that sinter at comparatively lower temperatures attaining high densification, and without using any milling procedure. The main results show that: 1- the dopant cation has a strong influence on the crystallization behavior of the precipitates; 2- the used techniques allowed for obtaining high values of specific surface area (∼130 m 2 .g -1 ); 3- the optimization of the synthesis and processing parameters are responsible for obtaining high densification (≥97% of the theoretical value), at lower temperatures (∼1200 deg C) with average grain sizes lower than 500 nm; 4- impedance spectroscopy results show a strong correlation between the electrical resistivity and the microstructure of sintered ceramics.(author)

  9. Evaluation of technological properties of alumina refractory systems-zirconia and zirconia-silica-alumina

    International Nuclear Information System (INIS)

    Marinho, A.R.O.; Carvalho, T.U.S.; Fagury Neto, E.; Rabelo, A.A.

    2014-01-01

    Alumina-zirconia refractories are noted for being products of excellent cost-effective, however, zirconia may limit its use due to decreasing resistance to thermal shock. This study aims to evaluate these refractories with the addition of microsilica, which can greatly improve their properties. Were used the following starting materials: calcined alumina, zirconia (stabilized and monoclinic) in amounts of 2%, 4% and 6% by weight, plus microsilica (5%w.). The powders were milled together with binder and lubricant for conformation bodies by uniaxial pressing. The samples were dried, calcined and sintered at 1400 °C/2h were characterized using the methods of Archimedes, and scanning electron microscopy (SEM), chemical analysis using energy dispersive X-ray (EDS), and mechanical flexural strength tests at room temperature. Formulations with the presence of microsilica showed satisfactory results and optimized properties. (author)

  10. Microstructural evolution of alumina-zirconia nanocomposites; Evolucao microestrutural de nanocompositos alumina-zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Ojaimi, C.L.; Chinelatto, A.S.A.; Chinelatto, A.L. [Universidade Estadual de Ponta Grossa (UEPG), PR (Brazil); Pallone, E.M.J.A., E-mail: christianelago@yahoo.com.br [Universidade de Sao Paulo (USP), Pirassununga, Sao Paulo, SP (Brazil). Faculdade de Zootecnia e Engenharia de Alimentos

    2012-07-01

    Ceramic materials have limited use due to their brittleness. The inclusion of nanosized particles in a ceramic matrix, which are called nanocomposites, and ceramic processing control by controlling the grain size and densification can aid in obtaining ceramic products of greater strength and toughness. Studies showed that the zirconia nano inclusions in the matrix of alumina favors an increase in mechanical properties by inhibiting the grain growth of the matrix and not by the mechanism of the transformation toughening phase of zirconia. In this work, the microstructural evolution of alumina nanocomposites containing 15% by volume of nanometric zirconia was studied. From the results it was possible to understand the sintering process of these nanocomposites. (author)

  11. Forensic examination of ink by high-performance thin layer chromatography--the United States Secret Service Digital Ink Library.

    Science.gov (United States)

    Neumann, Cedric; Ramotowski, Robert; Genessay, Thibault

    2011-05-13

    Forensic examinations of ink have been performed since the beginning of the 20th century. Since the 1960s, the International Ink Library, maintained by the United States Secret Service, has supported those analyses. Until 2009, the search and identification of inks were essentially performed manually. This paper describes the results of a project designed to improve ink samples' analytical and search processes. The project focused on the development of improved standardization procedures to ensure the best possible reproducibility between analyses run on different HPTLC plates. The successful implementation of this new calibration method enabled the development of mathematical algorithms and of a software package to complement the existing ink library. Copyright © 2010 Elsevier B.V. All rights reserved.

  12. Niobia and tantala codoped orthorhombic zirconia ceramics

    International Nuclear Information System (INIS)

    Hoeftberger, M.; Gritzner, G.

    1995-01-01

    During recent studies it was found that codoping of zirconia with niobia and tantala yielded very corrosion resistant, orthorhombic zirconia ceramics. The powders for those novel ceramics were made via the sol-gel technique by hydrolysis of the respective metal propoxides; a method which required dry-box techniques during the preparation of the alkoxides. In these studies the authors investigated the fabrication of precursor material from aqueous solutions. The preparation of aqueous solutions of salts of zirconium, niobium and tantalum is hampered by rapid hydrolysis. Premature hydrolysis of the chlorides and oxichlorides of niobium, tantalum and zirconium can be, however, prevented in aqueous solutions of oxalic acid. Thus the authors investigated the coprecipitation of hydroxides as precursors by reacting oxalic acid solutions of the respective cations with aqueous ammonia. In addition they studied the effects of calcination and of hydrothermal conversion of the hydroxides to oxides on the powder characteristics and on the mechanical properties of the niobia and tantala codoped zirconia ceramics

  13. Studies on zirconia-mullite ceramic

    International Nuclear Information System (INIS)

    Virkar, Alka N.

    2014-01-01

    Zirconia Toughened Alumina (ZTA) ceramics with much improved Fracture Toughness and Strength have been used as a front material to fabricate composite Armour-Applications, Al 2 O 3 has very different fluxing ability with silica by sufficiently lowering the melting point. Addition of small amount of Fe 2 O 3 , TiO 2 , in an Al 2 O 3 -SiO 2 mixture enhances needle shaped Mullite crystal growth and also assist Liquid phase Sintering. In the present investigation, Zircon was used as a source of ZrO 2 and SiO 2 . Zircon (ZrSiO 4 ) has a low coefficient of Thermal Expansion and good Thermal Shock Resistance. Densification in terms of Relative Density and App. Porosity, Tetragonal ZrO 2 , phases, Thermal Expansion Coefficient, Hardness etc. were studied on Zirconia-Mullite system with and without additives. Z-M system with Y 2 O 3 additives show improved properties owing to the partial stabilization of Zirconia phase (PSZ). (author)

  14. Stabilized zirconia with cerium and neodymium addition

    International Nuclear Information System (INIS)

    Andrade, I.M. de; Pessoa, R.C.; Nasar, M.C.; Nasar, R.S.; Rodriques, M.K.C.; Oliveira, J.F.

    2006-01-01

    Zr 0,9 Ce 0,05 Nd 0,05 O 1,975 system was synthesized with the use of the Pechini method. The polymeric resin was calcined at 350 deg C/3 h and analysed by FTIR that show bands relative to organic. Radicals esther type. The TGA curve indicated the polymeric decomposition occurring from 30 deg C to 740 deg C. DTA analysis show a exothermic peak in 100 deg C due to loss of water of material. From 500 deg C to 800 deg C was observed a intense peak due to polymer decomposition and the zirconia crystallization. The calcined powder from 350 deg C/3 h e 30 min to 900 deg/3 h were analysed by XRD that show the crystalline phase formation with the increase of temperature. The X-ray diffraction pattern show the presence of two phases, such as tetragonal and cubic of zirconia demonstrating that neodymium and cerium additions led to zirconia stabilization. (author)

  15. Analysis of the Aging Processes of Writing Ink: Raman Spectroscopy versus Gas Chromatography Aspects

    Directory of Open Access Journals (Sweden)

    Nikolai M. Grechukha

    2017-09-01

    Full Text Available This work is devoted to the extremely popular but poorly developed scientific and forensic problem of the estimation of the actual dates of inscriptions placed on paper and made by ballpoint pens. It is shown that the degradation of writing inks with time may be controlled via Raman spectroscopy and gas chromatography. The time intervals for the implementation of each of these methods were determined using the ratios of the Raman peak intensities as degradation characteristics rather than their absolute values. In turn, this eliminates the effect of the concentration of a dye. The mutual influence of the volatile components and dyes of writing inks was also investigated and the time interval within which such influence is critical was found. According to the obtained results, a new methodological scheme for determining the age of documents, which were created at least 40 months ago, was proposed.

  16. Tridodecylamine, an efficient charge control agent in non-polar media for electrophoretic inks application

    Science.gov (United States)

    Noel, Amélie; Mirbel, Déborah; Cloutet, Eric; Fleury, Guillaume; Schatz, Christophe; Navarro, Christophe; Hadziioannou, Georges; CyrilBrochon

    2018-01-01

    In order to obtain efficient electrophoretic inks, Tridodecylamine (Dod3N), has been studied as charge control agent (CCA) in a non-polar paraffin solvent (Isopar G) for various inorganic pigments (TiO2 and Fe2O3). All hydrophobic mineral oxides, i.e. treated with octyltrimethoxysilane (C8) or dodecyltrimethoxysilane (C12), were found to be negatively charged in presence of Dod3N. The electrophoretic mobilities of inorganic pigments seemed to be strongly dependent of their isoelectric point (IEP) and also of the concentration of dod3N with an optimum range between 10 and 20 mM depending on the pigments. Finally, an electrophoretic ink constituted of hydrophobic mineral oxides in presence of Dod3N was tested in a device. Its efficiency as charge control agent to negatively charge hydrophobic particles was confirmed through good optical properties and fast response time (220 ms at 200 kV m-1).

  17. Development of biometric DNA ink for authentication security.

    Science.gov (United States)

    Hashiyada, Masaki

    2004-10-01

    Among the various types of biometric personal identification systems, DNA provides the most reliable personal identification. It is intrinsically digital and unchangeable while the person is alive, and even after his/her death. Increasing the number of DNA loci examined can enhance the power of discrimination. This report describes the development of DNA ink, which contains synthetic DNA mixed with printing inks. Single-stranded DNA fragments encoding a personalized set of short tandem repeats (STR) were synthesized. The sequence was defined as follows. First, a decimal DNA personal identification (DNA-ID) was established based on the number of STRs in the locus. Next, this DNA-ID was encrypted using a binary, 160-bit algorithm, using a hashing function to protect privacy. Since this function is irreversible, no one can recover the original information from the encrypted code. Finally, the bit series generated above is transformed into base sequences, and double-stranded DNA fragments are amplified by the polymerase chain reaction (PCR) to protect against physical attacks. Synthesized DNA was detected successfully after samples printed in DNA ink were subjected to several resistance tests used to assess the stability of printing inks. Endurance test results showed that this DNA ink would be suitable for practical use as a printing ink and was resistant to 40 hours of ultraviolet exposure, performance commensurate with that of photogravure ink. Copyright 2004 Tohoku University Medical Press

  18. Electron beam hardening type copper plate printing ink

    International Nuclear Information System (INIS)

    Kawamura, Eiji; Inoue, Mitsuo; Kusaki, Satoichiro

    1989-01-01

    Copper plate printing is the printing method of filling ink in the parts of concave printing elements on a type area, and transferring the ink to a base, and it is the feature that the ink in the printing element parts of a print rises. Copper plate prints show profound feeling, in addition, its effect of preventing forgery is high. This method is generally called engraving printing, and is used frequently for printing various bills and artistic prints. The electron beam irradiation apparatus installed in the laboratory of the Printing Bureau, Ministry of Finance, is an experimental machine of area beam type, and is so constructed as to do batch conveyance and web conveyance. As the ink in printing element parts rises, the offset at the delivery part of a printing machine becomes a problem. Electron beam is superior in its transparency, and can dry instantaneously to the inside of opaque ink. At 200 kV of acceleration voltage, the ink of copper plate prints can be hardened by electron beam irradiation. The dilution monomers as the vehicle for ink were tested for their dilution capability and the effect of electron beam hardening. The problem in the utilization of electron beam is the deterioration of papers, and the counter-measures were tested. (K.I.)

  19. PIXE analysis of Italian ink drawings of the XVI century

    Science.gov (United States)

    Zucchiatti, A.; Climent-Font, A.; Enguita, O.; Fernandez-Jimenez, M. T.; Finaldi, G.; Garrido, C.; Matillas, J. M.

    2005-10-01

    The composition of inks in a group of 24 drawings of ten XVI century Italian painters, has been determined by PIXE at the external micro-beam line of the Centro de Micro Análisis de Materiales of the Universidad Autónoma de Madrid. Ink elemental thicknesses have been determined by comparison with a set of certified thin standards. A comprehensive comparison of inks has also been performed by renormalisation of spectra and definition of an ink-to-ink distance. The elemental compositions and the ink-to-ink distances give consistent results that are generally in line with the appearance of the drawings and add relevant instrumental information to the stylistic observation, revealing for example the presence of retouches and additions in different parts of a drawing. Cluster analysis performed on a subgroup of 13 artefacts from the Genoese painter Luca Cambiaso and his school has revealed a partition that separates neatly the work of the master from that of his followers.

  20. Microbial status and product labelling of 58 original tattoo inks.

    Science.gov (United States)

    Høgsberg, T; Saunte, D M; Frimodt-Møller, N; Serup, J

    2013-01-01

    European Council resolutions on tattoo ink introduce sterility and preservation of inks to protect customers. Inks used in Denmark are typically purchased over the internet from international suppliers and manufacturers from the US and the UK. In Denmark tattoo inks are regulated and labelled according to REACH as if they were plain chemicals. The objective of this study was to check the microbial product safety of unopened and opened tattoo ink stock bottles. Packaging, labelling, preservation, sterility and contamination with micro-organisms were studied. Physical inspection and culture of bacteria and fungi. Six of 58 unopened stock bottles (10%) were contaminated with bacteria and one of six samples (17%) of previously used stock bottles was contaminated. The bacterial species represented bacteria considered pathogenic in humans as well as non-pathogenic environmental bacteria. Yeast or moulds were detected in none of the samples. A total of 31% of the manufacturers informed only about the brand name. No information about content, sterility, risks or expiry date was indicated on the label. A total of 42% claimed sterility of their inks. A total of 54% labelled a maximum period of durability of typically 2-3 years. The physical sealing was leaking in 28% of the products. The European Council resolutions regarding safety of tattoo inks are not effective. Stock bottles of tattoo ink may contain bacteria pathogenic to humans and environmental bacteria, and packaging, labelling and preservation of inks are of inadequate quality. Claim of sterility can be erroneous. © 2011 The Authors. Journal of the European Academy of Dermatology and Venereology © 2011 European Academy of Dermatology and Venereology.

  1. 40 CFR 447.10 - Applicability; description of the oil-base solvent wash ink subcategory.

    Science.gov (United States)

    2010-07-01

    ...-base solvent wash ink subcategory. 447.10 Section 447.10 Protection of Environment ENVIRONMENTAL...-Base Solvent Wash Ink Subcategory § 447.10 Applicability; description of the oil-base solvent wash ink...-base ink where the tank washing system uses solvents. When a plant is subject to effluent limitations...

  2. Effect of surface treatment on flexural strength of zirconia bars

    NARCIS (Netherlands)

    Aboushelib, M.N.; Wang, H.

    2010-01-01

    Statement of problem Clinical and laboratory processing techniques induce damage to the surface of zirconia frameworks, which significantly lessens their strength. Purpose The purpose of this study was to investigate the influence of 3 surface restoration methods on the flexural strength of zirconia

  3. Sulfated zirconia modified SBA-15 catalysts for cellobiose hydrolysis

    NARCIS (Netherlands)

    Degirmenci, V.; Uner, D.; Cinlar, B.; Shanks, B.H.; Yilmaz, A.; Santen, van R.A.; Hensen, E.J.M.

    2011-01-01

    Zirconia modified SBA-15 becomes a very active catalyst for the selective hydrolysis of cellobiose to glucose after sulfation. Spectroscopic investigations indicate the presence of Brønsted acid sites with similar properties to those present in conventional sulfated zirconia. Indications are found

  4. Osseointegration of a Zirconia Implant : A Histologic Assessment

    NARCIS (Netherlands)

    Schepke, Ulf; Meijer, Gert J; Meijer, Henny Ja; Walboomers, X Frank; Cune, Marco

    2017-01-01

    PURPOSE: The aim of this study was to describe the histologic and histomorphometric features of a retrieved, functional endosseous zirconia implant in a human subject. MATERIALS AND METHODS: A maxillary zirconia implant (ZV3) placed in a 52-year-old man was retrieved after 2 years of uncompromised

  5. Antioxidant and antimicrobial activities of squid ink powder

    OpenAIRE

    Fatimah Zaharah, M.Y.; Rabeta, M.S.

    2017-01-01

    Economic development in Malaysia has led to increasing quantity and complexity of generated waste or by-product. The main objective of this study is to investigate the antioxidant and antimicrobial activities of squid ink powder. The squid ink was collected from fresh squid and dried using freeze dryer before it was ground into powder. The yield of squid ink was 22.82% after freeze-drying which was 69.37g in amount. Proximate composition analysis as well as two total antioxidant activity assa...

  6. Optimization of the conditions for producing zirconia by the precipitation of basic zirconium sulfate

    International Nuclear Information System (INIS)

    Ricci, D.R.; Paschoal, J.O.A.

    1988-01-01

    The process of precipitation of the basic sulfate from zirconium oxychlorides solutions has been optimized in order to obtain zirconia of high purity as well as suitable for ceramic processing. The main parameters of this study were obtained from the determination of the pH and of the concentration of the initial oxychloride solution, of the sulfate/zirconium molar ratio and of the reaction temperature. The following experimental procedure has been carried out: a) reaction of each precipitate with ammonium hydroxide followed by drying at 150 0 -C / 5 h and calcination at 1000 0 C / 1 h, yielding the final product (zirconia) b) product characterization by means of spectrographic, X - ray fluorescence and diffractometry analyses, determination of grain size distribution and of apparent density, and morphology study by scanning electron microscopy. The yielding of the overall reaction has been determined by chemical analysis and the composition of the basic zirconium sulfate by thermogravimetric analyses. (author) [pt

  7. Magnetic and electronic properties of half-metallic ferromagnetic Mn-stabilised zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Maznichenko, Igor; Daene, Markus; Hergert, Wolfram; Mertig, Ingrid [Martin-Luther-Univ. Halle-Wittenberg, Inst. Phys., 06099 Halle (Germany); Ernst, Arthur; Ostanin, Sergey; Sandratskii, Leonid; Bruno, Patrick [Max-Planck-Inst. Mikrostrukturphys., Weinberg 2, 06120 Halle (Germany); Bergqvist, Lars [Dept. Phys., Uppsala Univ., Box 530, 751 21 Uppsala (Sweden); Hughes, Ian; Staunton, Julie [Dept. Phys., Univ. Warwick, Coventry CV4 7AL (United Kingdom); Kudrnovsky, Josef [Max-Planck-Inst. Mikrostrukturphys., Weinberg 2, 06120 Halle (Germany); Inst. Phys., Acad. Sci. of the Czech Republic, Na Slovance 2, 18221 Prague (Czech Republic)

    2007-07-01

    The investigations of the manganese stabilised cubic zirconia (Mn-SZ) show that this dilute magnetic semiconductors possess unique magnetic properties. Based on ab-initio electronic structure calculations which include the effects of thermally excited magnetic fluctuations, the autors predict Mn-SZ to be ferromagnetic for a wide range of Mn concentration up to high T{sub C}. It was found that this material, which is well known both as a diamond imitation and as a catalyst, is halfmetallic with majority and minority spin states of the Mn impurities lying in the wide band gap of zirconia. The high T{sub C} ferromagnetism is robust against oxygen vacancies and against the distribution of Mn impurities on the Zr fcc sublattice. This work responds to the question concerning the key electronic and structure factors behind an optimal doping. The autors propose this stable half-metallic ferromagnet to be a promising candidate for future spintronics applications.

  8. Positron annihilation investigation and nuclear reaction analysis of helium and oxygen-implanted zirconia

    International Nuclear Information System (INIS)

    Grynszpan, R.I.; Saude, S.; Anwand, W.; Brauer, G.

    2005-01-01

    Since irradiation affects in-service properties of zirconia, we investigated the fluence dependence on production and thermal stability of defects induced by helium and oxygen-ion implantation in single crystals of yttria-fully-stabilized zirconia. In either case, depth profiling by slow positron implantation spectroscopy (SPIS) detects a distribution of vacancy-type defects peaking at 60% of the projected ion range R p . Owing to the saturation of positron-trapping occurring for low fluences, which depends on the ion mass, we could estimate a critical size of clusters ranging from 0.4 to 1.6 nm. The lack of SPIS-evidence of an open-volume excess at R p is explained by the presence of over-pressurized gas bubbles. This assumption is confirmed by Nuclear Reaction Analysis of 3 He concentration profiles, which shows that helium remains partly trapped at R p , even after annealing above 400 o C

  9. Transmutation of americium and curium incorporated in zirconia-based host materials

    International Nuclear Information System (INIS)

    Raison, P.E.

    2001-01-01

    Presented are studies involving the incorporation of americium and curium in zirconia-based materials. First explored was the pseudo ternary system AmO 2 -ZrO 2 -Y 2 O 3 . It was determined that selected Y-CSZ materials can incorporate significant quantities of americium oxide and remain cubic single-phase. The cell parameters of these fluorite-type products were established to be linear with the AmO 2 content. The Cm 2 O 3 -ZrO 2 system was also investigated. It was found that at 25 mol% of CmO 1.5 , the Cm(III) stabilized zirconia in its cubic form (a = 5.21 ±0.01 Angstrom). At higher and lower concentrations, diphasic materials were encountered. At 50 mol% of CmO 1.5 , a pyrochlore oxide - Cm 2 Zr 2 O 7 - is formed (a = 10.63 ±0.02 Angstrom). (author)

  10. Wear properties of alumina/zirconia composite ceramics for joint prostheses measured with an end-face apparatus.

    Science.gov (United States)

    Morita, Yusuke; Nakata, Kenichi; Kim, Yoon-Ho; Sekino, Tohru; Niihara, Koichi; Ikeuchi, Ken

    2004-01-01

    While only alumina is applied to all-ceramic joint prostheses at present, a stronger ceramic is required to prevent fracture and chipping due to impingement and stress concentration. Zirconia could be a potential substitute for alumina because it has high strength and fracture toughness. However, the wear of zirconia/zirconia combination is too high for clinical use. Although some investigations on composite ceramics revealed that mixing of different ceramics was able to improve the mechanical properties of ceramics, there are few reports about wear properties of composite ceramics for joint prosthesis. Since acetabular cup and femoral head of artificial hip joint are finished precisely, they indicate high geometric conformity. Therefore, wear test under flat contact was carried out with an end-face wear testing apparatus for four kinds of ceramics: alumina monolith, zirconia monolith, alumina-based composite ceramic, and zirconia based composite ceramic. Mean contact pressure was 10 MPa and sliding velocity was 40 mm/s. The wear test continued for 72 hours and total sliding distance was 10 km. After the test, the wear factor was calculated. Worn surfaces were observed with a scanning electron micrograph (SEM). The results of this wear test show that the wear factors of the both composite ceramics are similarly low and their mechanical properties are much better than those of the alumina monolith and the zirconia monolith. According to these results, it is predicted that joint prostheses of the composite ceramics are safer against break down and have longer lifetime compared with alumina/alumina joint prostheses.

  11. Analysis of Printing Substrate, Ink Age and Number of IR Drying Influence on Electrical Resistance of Conductive Inks

    Directory of Open Access Journals (Sweden)

    Josip Jerić

    2015-05-01

    Full Text Available As a result of availability of new technologies, functional printing as a segment has become one of the most interesting directions of research and development in graphic technology. Conductive inks are not a novelty and they already have broad possibilities in production of everyday products. There is still a big market for the broadening of their use, as well as a possibility of further enhancing their properties. This paper analyzes the influence of printing substrate, age of ink and the number of IR drying on the electrical resistance of the conductive inks. In the paper, subject of analysis was the change of electrical resistance in the line that was 9 cm long and 10 typographic points wide. The semi-automated screen-printing machine was used for printing. Three types of printing substrates were used; uncoated, coated and recycled paper. Two types of inks were used; newly opened ink and ink that was out of date for half year. After the printing, prints were dried using the IR dryer. Prints were dried once, and then additional three times. After the first and last drying, multimeter was used to measure electrical resistance of the lines. Analysis of the data shows that the older ink produces prints with higher electrical resistance. There are also notable differences in the electrical resistance based on the printing substrate.

  12. Damage Maps of Veneered Zirconia under Simulated Mastication

    Science.gov (United States)

    Kim, Jae-Won; Kim, Joo-Hyung; Janal, Malvin N.; Zhang, Yu

    2016-01-01

    Zirconia based restorations often fracture from chipping and/or delamination of the porcelain veneers. We hypothesize that veneer chipping/delamination is a result of the propagation of near-contact induced partial cone cracks on the occlusal surface under mastication. Masticatory loading involves the opposing tooth sliding along the cuspal inner incline surface with an applied biting force. To test this hypothesis, flat porcelain veneered zirconia plates were cemented to dental composites and cyclically loaded (contact–slide–liftoff) at an inclination angle as a simplified model of zirconia based restorations under occlusion. In the light of in-situ observation of damage evolution in a transparent glass/zirconia/polycarbonate trilayer, postmortem damage evaluation of porcelain/zirconia/composite trilayers using a sectioning technique revealed that deep penetrating occlusal surface partial cone fracture is the predominant fracture mode of porcelain veneers. Clinical relevance is discussed. PMID:19029080

  13. Internal Nano Voids in Yttria-Stabilised Zirconia (YSZ Powder

    Directory of Open Access Journals (Sweden)

    Chen Barad

    2017-12-01

    Full Text Available Porous yttria-stabilised zirconia ceramics have been gaining popularity throughout the years in various fields, such as energy, environment, medicine, etc. Although yttria-stabilised zirconia is a well-studied material, voided yttria-stabilised zirconia powder particles have not been demonstrated yet, and might play an important role in future technology developments. A sol-gel synthesis accompanied by a freeze-drying process is currently being proposed as a method of obtaining sponge-like nano morphology of embedded faceted voids inside yttria-stabilised zirconia particles. The results rely on a freeze-drying stage as an effective and simple method for generating nano-voided yttria-stabilised zirconia particles without the use of template-assisted additives.

  14. Shear bond strength of indirect composite material to monolithic zirconia.

    Science.gov (United States)

    Sari, Fatih; Secilmis, Asli; Simsek, Irfan; Ozsevik, Semih

    2016-08-01

    This study aimed to evaluate the effect of surface treatments on bond strength of indirect composite material (Tescera Indirect Composite System) to monolithic zirconia (inCoris TZI). Partially stabilized monolithic zirconia blocks were cut into with 2.0 mm thickness. Sintered zirconia specimens were divided into different surface treatment groups: no treatment (control), sandblasting, glaze layer & hydrofluoric acid application, and sandblasting + glaze layer & hydrofluoric acid application. The indirect composite material was applied to the surface of the monolithic zirconia specimens. Shear bond strength value of each specimen was evaluated after thermocycling. The fractured surface of each specimen was examined with a stereomicroscope and a scanning electron microscope to assess the failure types. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey LSD tests (α=.05). Bond strength was significantly lower in untreated specimens than in sandblasted specimens (Pcomposite material and monolithic zirconia.

  15. Effect of hydrothermal treatment on light transmission of translucent zirconias.

    Science.gov (United States)

    Putra, Armand; Chung, Kwok-Hung; Flinn, Brian D; Kuykendall, Tuesday; Zheng, Cheng; Harada, Kosuke; Raigrodski, Ariel J

    2017-09-01

    Studies of the light transmission of translucent zirconias after hydrothermal treatment are limited. The purpose of this in vitro study was to evaluate the effect of hydrothermal treatment on the light transmission of translucent zirconias for monolithic restorations. Four commercially available zirconia products, BruxZir Anterior Solid Zirconia (BruxAnt, BA), Lava Plus High Translucency (LPHT), Katana Zirconia Super Translucent (KST), and Katana Zirconia Ultra Translucent (KUT) were assessed and 1 type of lithium disilicate, e.max Press LT (LDLT) was used as a control. Plate specimens, 20×20×1 mm (n=80) for the translucency assessment were sectioned from postsintered zirconia bulk materials and ground with a #400-grit diamond wheel and coolant. The specimens were placed under hydrothermal conditions of 134°C at 0.2 MPa (n=5 per group at 0, 5, 50, and 100 hours). Percentage of total transmittance of light (T t %) of each specimen was measured using a spectrophotometer with an integrating sphere. X-ray diffraction analyses were used to measure tetragonal-monoclinic phase transformation. Surfaces were examined by scanning electron microscopy and energy dispersive spectrometry. Data were analyzed using 2-way ANOVA followed by the Tukey test (α=.05). The T t % ranged from 6.5% to 28.3%. Group LDLT obtained significantly higher transmittance than other tested groups, whereas groups KST and KUT had significantly higher T t % than groups BA and LPHT (Phydrothermal treatment for all tested translucent zirconias and a lithium disilicate glass-ceramic control. Hydrothermal treatment had minimal effects on the translucency of translucent zirconias. The tetragonal-monoclinic phase transformation rate of translucent zirconias was found to be low, except in group LPHT. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  16. Ink dating part II: Interpretation of results in a legal perspective

    OpenAIRE

    Koenig, Agnès; Weyermann, Céline

    2018-01-01

    The development of an ink dating method requires an important investment of resources in order to step from the monitoring of ink ageing on paper to the determination of the actual age of a questioned ink entry. This article aimed at developing and evaluating the potential of three interpretation models to date ink entries in a legal perspective: (1) the threshold model comparing analytical results to tabulated values in order to determine the maximal possible age of an ink entry, (2) the tre...

  17. Chemical treatment and biomimetic coating evaluating in zirconia-alumina ceramics

    International Nuclear Information System (INIS)

    Aguiar, Amanda Abati

    2007-01-01

    Ceramic materials, as alumina and zirconia have been explored along the years as biomaterials application. The bio inert nature has been stimulating the development of new alternatives, as chemical treatments to improve the biological application of these ceramics. The biomimetic process of bio inert ceramics for coating apatite is based on soaking the implant in a simulated body fluid, SBF, with ion concentrations nearly equal to those of human blood plasma. The bioactivity of the material is related with the formation of a layer constituted of hydroxyapatite low crystalline, similar to the biological apatite. The biocompatibility associated to the structural properties of the alumina and zirconia has been stimulating the clinical use of these materials, mainly in areas of larger mechanical requests, places not recommended for bioactive hydroxyapatite, for instance. In this work samples of alumina, zirconia doped with Yttria (3% mol) and composites of alumina and zirconia doped with Yttria (3% mol) were prepared by co-precipitation method, calcinate, sintered, chemically treated with solutions of acid phosphoric and sodium hydroxide and them immersed in 1.0 M and 1.5 M SBF. The calcinate powders were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), gas adsorption (BET) and laser diffraction. The XRD results indicate that the samples are low crystalline. It was observed for BET that the samples present high specific surface area. The results of laser diffraction and SEM showed that the powders are agglomerates. The sintered samples were analyzed by XRD, SEM and X-ray fluorescence (XRF). The phases quantified by Rietveld method were: cubic, tetragonal and monoclinic of the zirconia, besides the phase alpha of the alumina. The chemical treatment with phosphoric acid didn't present a tendency of larger apatite formation in relation to the samples no chemically treated. The treatment with sodium hydroxide provoked accentuated transformation of

  18. The preparation of ZnO based gas-sensing thin films by ink-jet printing method

    International Nuclear Information System (INIS)

    Shen Wenfeng; Zhao Yan; Zhang Caibei

    2005-01-01

    An ink-jet printing technique was applied to prepare ZnO based gas-sensing thin films. ZnO inks with appropriate viscosity and surface tension were prepared by sol-gel techniques, and printed onto substrates using a commercial printer. After the drying and heating treatment processes, continuous ZnO films were formed and studied by scanning electron microscopy, X-ray diffraction and by a home-made gas sensitivity measuring system. It was found that the morphology and electrical properties of the films changed significantly with the thickness of the films, which can be adjusted simply by printing on the film with increasing frequency. Highest resistance and sensitivity to acetone vapor were obtained when the film was prepared by printing only once on it. Different dopants with certain concentrations could be added into the films by printing with different dopant inks and printing frequency. All Pd, Ag, and ZrO 2 dopants increased both the resistivity and the sensitivity of the films (180 ppm acetone). This work showed that the ink-jet printing technique was a convenient and low cost method to prepare films with controlled film thickness and dopant concentration

  19. Fabrication of an organic field effect transistor using nano imprinting of Ag inks and semiconducting polymers

    International Nuclear Information System (INIS)

    Hu, PingAn; Li, Kun; O'Neill, William; Chen, Weilin; Peng, Li; Chu, Daping

    2010-01-01

    A simple and cheap procedure for flexible electronics fabrication was demonstrated by imprinting metallic nanoparticles (NPs) on flexible substrates. Silver NPs with an average diameter of 10 nm were prepared via an improved chemical approach and Ag Np ink was produced in α-terpineol with a concentration up to 15%. Silver micro/nanostructures with a dimension varying from nanometres to microns were produced on a flexible substrate (polyimide) by imprinting the as-prepared silver ink. The fine fluidic properties of an Ag NP/α-terpineol solution and low melting temperatures of silver nanoparticles render a low pressure and low temperature procedure, which is well suited for flexible electronics fabrication. The effects of sintering and mechanical bending on the conductivity of imprinted silver contacts were also investigated. Large area organic field effect transistors (OFET) on flexible substrates were fabricated using an imprinted silver electrode and semiconducting polymer. The OFET with silver electrodes imprinted from our prepared oleic acid stabilized Ag nanoparticle ink show an ideal ohmic contact; therefore, the OFET exhibit high performance (I on /I off ratio: 1 × 10 3 ; mobility: 0.071 cm 2 V −1 s −1 ).

  20. InkTag: Secure Applications on an Untrusted Operating System.

    Science.gov (United States)

    Hofmann, Owen S; Kim, Sangman; Dunn, Alan M; Lee, Michael Z; Witchel, Emmett

    2013-01-01

    InkTag is a virtualization-based architecture that gives strong safety guarantees to high-assurance processes even in the presence of a malicious operating system. InkTag advances the state of the art in untrusted operating systems in both the design of its hypervisor and in the ability to run useful applications without trusting the operating system. We introduce paraverification , a technique that simplifies the InkTag hypervisor by forcing the untrusted operating system to participate in its own verification. Attribute-based access control allows trusted applications to create decentralized access control policies. InkTag is also the first system of its kind to ensure consistency between secure data and metadata, ensuring recoverability in the face of system crashes.

  1. Versatile Molecular Silver Ink Platform for Printed Flexible Electronics.

    Science.gov (United States)

    Kell, Arnold J; Paquet, Chantal; Mozenson, Olga; Djavani-Tabrizi, Iden; Deore, Bhavana; Liu, Xiangyang; Lopinski, Gregory P; James, Robert; Hettak, Khelifa; Shaker, Jafar; Momciu, Adrian; Ferrigno, Julie; Ferrand, Olivier; Hu, Jian Xiong; Lafrenière, Sylvie; Malenfant, Patrick R L

    2017-05-24

    A silver molecular ink platform formulated for screen, inkjet, and aerosol jet printing is presented. A simple formulation comprising silver neodecanoate, ethyl cellulose, and solvent provides improved performance versus that of established inks, yet with improved economics. Thin, screen-printed traces with exceptional electrical (molecular ink platform enables an aerosol jet-compatible ink that yields conductive features on glass with 2× bulk resistivity and strong adhesion to various plastic substrates. An inkjet formulation is also used to print top source/drain contacts and demonstrate printed high-mobility thin film transistors (TFTs) based on semiconducting single-walled carbon nanotubes. TFTs with mobility values of ∼25 cm 2 V -1 s -1 and current on/off ratios >10 4 were obtained, performance similar to that of evaporated metal contacts in analogous devices.

  2. Fire-retardant decorative inks for aircraft interiors

    Science.gov (United States)

    Kourtides, D. A.; Nir, Z.; Mikroyannidis, J. A.

    1985-01-01

    Commercial and experimental fire retardants were screened as potential fire retardants for acrylic printing inks used on aircraft interior sandwich panels. The fire retardants are selected according to their physical properties and their thermostabilities. A criterion for selecting a more stable fire retardant is established. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) are used to determine thermostabilities. Results show that the fire retardant formulations are more thermally stable than the acrylic ink control. It is determined that an ink formulation containing a brominated phenol and carboxy-terminated butadiene acrylonitrile which has been modified with a brominated polymeric additive (BPA), yields the highest limiting oxygen index (LOI) of all the compounds tested. All of the fire-retardant formulations have a higher oxygen index than the baseline acrylic ink.

  3. Study of inks on paper engravings using portable EDXRF spectrometry

    International Nuclear Information System (INIS)

    Ferrero, J.L.; Roldan, C.; Juanes, D.; Carballo, J.; Pereira, J.; Ardid, M.; Lluch, J.L.; Vives, R.

    2004-01-01

    The prints are fragile and delicate art objects that need for its examination a suitable technique for 'in situ', non-destructive and rapid analyses. The energy dispersive X-ray Fluorescence (EDXRF) spectrometry with portable instrumentation offers these analytical properties. In this work we present the EDXRF analyses of eight engravings elaborated with different techniques (etching and heliogravure) from the 17th to 20th centuries. The characterization of the paper is directly done from its EDXRF spectra, whereas the inks are characterized by the ink plus paper analysis after subtracting the background from the paper spectrum. Inorganic components of the paper engravings and inks have been identified from the EDXRF spectra and the results are discussed. Also, we present EDXRF analyses for the identification of inorganic components from six samples of modern inks

  4. InkTag: Secure Applications on an Untrusted Operating System

    Science.gov (United States)

    Hofmann, Owen S.; Kim, Sangman; Dunn, Alan M.; Lee, Michael Z.; Witchel, Emmett

    2014-01-01

    InkTag is a virtualization-based architecture that gives strong safety guarantees to high-assurance processes even in the presence of a malicious operating system. InkTag advances the state of the art in untrusted operating systems in both the design of its hypervisor and in the ability to run useful applications without trusting the operating system. We introduce paraverification, a technique that simplifies the InkTag hypervisor by forcing the untrusted operating system to participate in its own verification. Attribute-based access control allows trusted applications to create decentralized access control policies. InkTag is also the first system of its kind to ensure consistency between secure data and metadata, ensuring recoverability in the face of system crashes. PMID:24429939

  5. Temperature dependence of bending strength for plasma sprayed zirconia coating; Plasuma yosha zirconia himaku no magetsuyosa no ondo izonsei

    Energy Technology Data Exchange (ETDEWEB)

    Arai, M.; Sakuma, T. [Central Research Inst. of Electric Power Industry, Tokyo (Japan)] Mizutani, T. [Tokyo Inst. of Tech. (Japan)] Kishimoto, K. [Tokyo Inst. of Tech. (Japan). Faculty of Engineering] Saito, M. [Toshiba Corp. (Japan). Heavy Apparatus Engineering Lab.

    1998-02-01

    Plasma sprayed zirconia applying to the thermal barrier coating in gas turbine has been developing for protecting the hot parts such as blades and nozzles from high-temperature enviroments. In this paper, four point bending tests under various temperature conditions are conducted on plasma sprayed zirconia and its mechanical properties are examined. Results show that the bending strength at room temperature for plasma sprayed zirconia is much lower than that of sintered zirconia and is decreased with the increase in temperature. However, Weibull modulus at each temperature is relatively large and the dispersion of bending strength is very small in comparison with that of sintered zirconia. It is also clarified by the SEM observations of fracture surface that many defects such as debonding and microcrack are responsible for the lower bending strength. 9 refs., 8 figs., 1 tab.

  6. The potential of artificial aging for modelling of natural aging processes of ballpoint ink.

    Science.gov (United States)

    Weyermann, Céline; Spengler, Bernhard

    2008-08-25

    Artificial aging has been used to reproduce natural aging processes in an accelerated pace. Questioned documents were exposed to light or high temperature in a well-defined manner in order to simulate an increased age. This may be used to study the aging processes or to date documents by reproducing their aging curve. Ink was studied especially because it is deposited on the paper when a document, such as a contract, is produced. Once on the paper, aging processes start through degradation of dyes, solvents drying and resins polymerisation. Modelling of dye's and solvent's aging was attempted. These processes, however, follow complex pathways, influenced by many factors which can be classified as three major groups: ink composition, paper type and storage conditions. The influence of these factors is such that different aging states can be obtained for an identical point in time. Storage conditions in particular are difficult to simulate, as they are dependent on environmental conditions (e.g. intensity and dose of light, temperature, air flow, humidity) and cannot be controlled in the natural aging of questioned documents. The problem therefore lies more in the variety of different conditions a questioned document might be exposed to during its natural aging, rather than in the simulation of such conditions in the laboratory. Nevertheless, a precise modelling of natural aging curves based on artificial aging curves is obtained when performed on the same paper and ink. A standard model for aging processes of ink on paper is therefore presented that is based on a fit of aging curves to a power law of solvent concentrations as a function of time. A mathematical transformation of artificial aging curves into modelled natural aging curves results in excellent overlap with data from real natural aging processes.

  7. Inactivation of p15INK4b in chronic arsenic poisoning cases

    Directory of Open Access Journals (Sweden)

    Aihua Zhang

    2014-01-01

    Full Text Available Arsenic exposure from burning high arsenic-containing coal has been associated with human skin lesion and cancer. However, the mechanisms of arsenic-related carcinogenesis are not fully understood. Inactivation of critical tumor suppression genes by epigenetic regulation or genetic modification might contribute to arsenic-induced carcinogenicity. This study aims to clarify the correlation between arsenic pollution and functional defect of p15INK4b gene in arsenic exposure residents from a region of Guizhou Province, China. To this end, 103 arsenic exposure residents and 105 control subjects were recruited in this study. The results showed that the exposure group exhibited higher levels of urinary and hair arsenic compared with the control group (55.28 vs 28.87 μg/L, 5.16 vs 1.36 μg/g. Subjects with higher arsenic concentrations are more likely to have p15INK4b methylation and gene deletion (χ2 = 4.28, P = 0.04 and χ2 = 4.31, P = 0.04. We also found that the degree of p15INK4b hypermethylation and gene deletion occurred at higher incidence in the poisoning cases with skin cancer (3.7% and 14.81% in non-skin cancer group, 41.18% and 47.06 in skin cancer group, and were significantly associated with the stage of skin lesions (χ2 = 12.82, P < 0.01 and χ2 = 7.835, P = 0.005. These observations indicate that inactivation of p15INK4b through genetic alteration or epigenetic modification is a common event that is associated with arsenic exposure and the development of arsenicosis.

  8. Intramantle Inking: A Stress Behavior in Octopus bimaculoides (Mollusca: Cephalopoda)

    Science.gov (United States)

    Toll, Ronald B

    2011-01-01

    Several Pacific 2-spot octopuses (Octopus bimaculoides) shipped from California and held in a recirculating seawater system at Illinois College exhibited an unusual postshipping stress behavior not previously documented in the literature. Ink, normally ejected into the surrounding seawater, was uncharacteristically retained in the mantle cavity. We describe the resulting behaviors, discuss successful resuscitation efforts, and briefly consider the possible role(s) that ink may have played in the death of one octopus. PMID:22330791

  9. Antioxidant and antimicrobial activities of squid ink powder

    Directory of Open Access Journals (Sweden)

    Fatimah Zaharah, M.Y.

    2017-10-01

    Full Text Available Economic development in Malaysia has led to increasing quantity and complexity of generated waste or by-product. The main objective of this study is to investigate the antioxidant and antimicrobial activities of squid ink powder. The squid ink was collected from fresh squid and dried using freeze dryer before it was ground into powder. The yield of squid ink was 22.82% after freeze-drying which was 69.37g in amount. Proximate composition analysis as well as two total antioxidant activity assays named 2,2-diphenyl-1-picrylhydrazyl (DPPH assay and Ferric Reducing Antioxidant Power (FRAP assay, and antimicrobial analysis were done on the powdered squid ink. The proximate results of squid ink powder were 4.43 ± 0.29% moisture, 62.46 ± 0.62% protein, 3.96 ± 0.08% fat, and 9.29 ± 0.05% ash. Results of DPPH assay showed that water extraction of squid ink powder has the highest 94.87 ± 4.87%, followed by ethanol 67.57 ± 7.55%, and hexane extract 2.10 ± 1.18%. FRAP assay result presented the same trend with water extraction had the highest value of 929.67 ± 2.31 μmol Fe (II / g of sample extract, followed by ethanol extract 201.00 ± 26.29 μmol Fe (II per gram sample and hexane 79.67 ± 12.66 μmol Fe (II / g of sample extract. Both water and ethanol extract showed antimicrobial properties with inhibition range of 7 to 15 mm, respectively. Fresh squid ink had 1.254 × 103 colony forming unit per gram of sample of microbial content. Squid ink powder had protein as major compound and microbial content was below from standard value of fisheries products as stated in Food Act 1983 and Regulation 1985.

  10. Optically Variable Inks (OVI): versatility in formulation and usage

    Science.gov (United States)

    Degott, Pierre

    2000-04-01

    Optically Variable Inks (OVI) are printing inks containing high precision, multi-layer interference filters as their constituent pigment. They display a strong and unique color change form a normal to an angled viewing position. During the last 10 years OVI has gained wide acceptance as an overt protection for numerous value documents including banknotes and ID cards. Meanwhile, continuous improvement has taken place over the last two years in a variety of areas.

  11. Degradation of inkjet ink by greensand and ultrasonic sonification

    OpenAIRE

    Mirela Rožić; Marina Vukoje; Kristinka Vinković; Nives Galić; Mirela Jukić

    2017-01-01

    The study describes the degradation of inkjet ink at low frequency ultrasound (US) and greensand to compare their reactivity. Environmental sonochemistry is a rapidly growing area and an example of the advanced oxidation process (AOP) that deals with the destruction of organic species in aqueous solutions. Greensand is a granular material coated with a thin layer of manganese dioxide (MnO2) which is among the strongest natural oxidants. In our study magenta inkjet water-based printing ink was...

  12. Studies of alumina additions in zirconia - magnesia

    International Nuclear Information System (INIS)

    Muccillo, R.

    1987-01-01

    Ionic conductivity measurements have been carried out in the 500 0 C - 1000 0 C temperature range in Mg - PSZ (Partially Stabilized Zirconia) with 0.5 to 10 mol % alumina additions. All specimens were prepared by pressing followed by pre - and sintering at 1000 0 C/2h and1450 0 C/4h, respectively. Thermal histerysis of the ionic conductivity have been detected, probably due to phase changes in the Mg-PSZ samples. The results show that alumina additions up to 2.1% enhances densification with no major variations in electrical resistivity values. (Author) [pt

  13. Ink for Ink-Jet Printing of Electrically Conductive Structures on Flexible Substrates with Low Thermal Resistance

    Science.gov (United States)

    Mościcki, A.; Smolarek-Nowak, A.; Felba, J.; Kinart, A.

    2017-07-01

    The development of new technologies in electronics related to flexible polymeric substrates forces the industry to introduce suitable tools (special type of dispensers) and modern conductive materials for printing electronic circuits. Moreover, due to the wide use of inexpensive polymeric foils (polyethene, PE, or poly(ethylene terephthalate), PET), there is a need to develop materials with the lowest possible processing temperatures. The present paper presents the selection criteria of suitable components and their preparation for obtaining electrically conductive ink with a special nanosilver base. In the case of the discussed solution, all components allow to make circuits in relatively low sintering temperature (even below 130°C). Additionally, the authors show the most significant ink parameters that should be taken into consideration during Research and Development (R&D) works with electrically conductive inks. Moreover, ink stability parameters are discussed and some examples of printed circuits are presented.

  14. Ballpoint pen inks: characterization by positive and negative ion-electrospray ionization mass spectrometry for the forensic examination of writing inks.

    Science.gov (United States)

    Ng, Lay-Keow; Lafontaine, Pierre; Brazeau, Luc

    2002-11-01

    A method based on profiling of dye components by electrospray ionization mass spectrometry (ESI/MS) is described for the characterization of ballpoint pen inks. The method involves benzyl alcohol (30 microL) extraction of ink from paper. The extracts of ink lines 1 and 5 mm in length are used for direct ESI/MS analysis in positive and negative modes, respectively. The instrumental analysis takes 3 min. Basic and acid dyes in the inks are detected in the positive and negative modes, respectively, with each dye yielding one or two characteristic ion peaks. The mass spectrum, which is mainly a compositional signature of the dyes in the ink, was not affected by the type of paper from which the ink was extracted, or by natural ageing of the ink on document in the absence of light. However, exposure to fluorescent illumination caused dealkylation of polyalkylated basic dyes and resulted in changes in the homologous distribution of the dyes. In this study, a total of 44 blue inks, 23 black inks, and 10 red inks have been analyzed, and the mass spectra were used to establish a searchable library. ESI/MS analysis provides a simple and fast way to compare ink specimens and in combination with on-line library search permits rapid screening of inks for forensic document investigations.

  15. Effect of dysprosia doping on structural and electrical property of stabilized zirconia for intermediate- temperature SOFCs

    International Nuclear Information System (INIS)

    Pastor, M.; Maiti, S.; Pandey, A.; Biswas, K.; Manna, I.

    2011-01-01

    Present work deals with structural, micro-structural and electrical properties of dysprosia stabilized zirconia electrolyte, which have been evaluated by means of X-ray diffraction (XRD) and scanning (SEM), and complex impedance analysis respectively. The amount of dysprosia was varied from 2 to 12 mol% in zirconia. The addition of dysprosia (8-12 mol%) stabilized the cubic zirconia phase, which was analyzed from XRD analysis. SEM micrographs clearly showed the improvement in sinterability with increase in dysprosia concentration up to 6 mol% disprosia. Complex impedance analysis was performed in the temperature range from 250 to 600 deg. C. The results indicated a gradual decrease in impedance of both bulk and grain boundary and increase in conductivity with dysprosia doping up to 6 mol% and thereafter showing a reverse trend. The activation energies for oxygen ion migration were also found to decrease with increase in dysprosia doping which was in the range of 0.99 - 1.28 eV. The average thermal expansion coefficient increases linearly.

  16. Zirconia based inert matrix fuel: fabrication concepts and feasibility studies

    International Nuclear Information System (INIS)

    Ingold, F.; Burghartz, M.; Ledergerber, G.

    1999-01-01

    The internal gelation process has traditionally been applied to fabricate standard fuel based on uranium, typically UO2 and MOX. To meet the recent aim to destroy plutonium in the most effective way, a uranium free fuel was evaluated. The fuel development programme at PSI has been redirected toward a fuel based on zirconium oxide or a mixture of zirconia and a conducting material to form ceramic/metal (CERMET) or ceramic/ceramic (CERCER) combinations. A feasibility study was carried out to demonstrate that microspheres based on zirconia and spinel can be fabricated with the required properties. The gelation parameters were investigated to optimise compositions of the starting solutions. Studies to fabricate a composite material (from zirconia and spinel) are ongoing. If the zirconia/spinel ratio is chosen appropriately, the low thermal conductivity of pure zirconia can be compensated by the higher thermal conductivity of spinel. Another solution to offset the low thermal conductivity of zirconia is the development of a CERMET, which consists of fine particles bearing plutonium in a cubic zirconia lattice dispersed in a metallic matrix. The fabrication of such a CERMET is also being studied. (author)

  17. Densification of zirconia films by coevaporation with silica

    International Nuclear Information System (INIS)

    Feldman, A.; Farabaugh, E.N.

    1985-04-01

    Optical films of zirconia have been receiving considerable attention because of their potential use as the high-index layer in multilayer optical coatings for the ultraviolet portion of the spectrum. Several problems are associated with electron-beam deposited zirconia films, including index instability and index inhomogeneity. The index instability is caused by the adsorption and the desorption of water in the porous columnar structure of the zirconia films. Index inhomogeneity is due to the inhomogeneous structure in the films. Recent work has shown that the first several tens of nanometers of a film possess a cubic structure, whereas the outmost layers possess a monoclinic structure. One approach for producing bulk-like zirzonia films that is receiving considerable attention at present is ion-assisted electron-beam deposition. This is because the method has successfully produced zirconia films having bulk-like densities and refractive indices that show insignificant sensitivity to water adsorption. In this paper a similar effect is demonstrated when mixed zirconia:silica films are produced by coevaporation from independent electron-beam sources, and, in particular, it is shown that the admixture of a small amount of silica with the zirconia produces a film possessing a higher refractive index than a pure zirconia film

  18. Cytotoxicity and physicochemical characterization of iron–manganese-doped sulfated zirconia nanoparticles

    Science.gov (United States)

    Al-Fahdawi, Mohamed Qasim; Rasedee, Abdullah; Al-Qubaisi, Mothanna Sadiq; Alhassan, Fatah H; Rosli, Rozita; El Zowalaty, Mohamed Ezzat; Naadja, Seïf-Eddine; Webster, Thomas J; Taufiq-Yap, Yun Hin

    2015-01-01

    Iron–manganese-doped sulfated zirconia nanoparticles with both Lewis and Brønsted acidic sites were prepared by a hydrothermal impregnation method followed by calcination at 650°C for 5 hours, and their cytotoxicity properties against cancer cell lines were determined. The characterization was carried out using X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, Brauner–Emmett–Teller (BET) surface area measurements, X-ray fluorescence, X-ray photoelectron spectroscopy, zeta size potential, and transmission electron microscopy (TEM). The cytotoxicity of iron–manganese-doped sulfated zirconia nanoparticles was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays against three human cancer cell lines (breast cancer MDA-MB231 cells, colon carcinoma HT29 cells, and hepatocellular carcinoma HepG2 cells) and two normal human cell lines (normal hepatocyte Chang cells and normal human umbilical vein endothelial cells [HUVECs]). The results suggest for the first time that iron–manganese-doped sulfated zirconia nanoparticles are cytotoxic to MDA-MB231 and HepG2 cancer cells but have less toxicity to HT29 and normal cells at concentrations from 7.8 μg/mL to 500 μg/mL. The morphology of the treated cells was also studied, and the results supported those from the cytotoxicity study in that the nanoparticle-treated HepG2 and MDA-MB231 cells had more dramatic changes in cell morphology than the HT29 cells. In this manner, this study provides the first evidence that iron–manganese-doped sulfated zirconia nanoparticles should be further studied for a wide range of cancer applications without detrimental effects on healthy cell functions. PMID:26425082

  19. Glass ceramic toughened with tetragonal zirconia

    Science.gov (United States)

    Keefer, Keith D.; Michalske, Terry A.

    1986-01-01

    A phase transformation-toughened glass ceramic and a process for making it are disclosed. A mixture of particulate network-forming oxide, network-modifying oxide, and zirconium oxide is heated to yield a homogeneous melt, and this melt is then heat-treated to precipitate an appreciable quantity of tetragonal zirconia, which is retained at ambient temperature to form a phase transformation-toughened glass ceramic. Nucleating agents and stabilizing agents may be added to the mixture to facilitate processing and improve the ceramic's properties. Preferably, the mixture is first melted at a temperature from 1200.degree. to 1700.degree. C. and is then heat-treated at a temperature within the range of 800.degree. to 1200.degree. C. in order to precipitate tetragonal ZrO.sub.2. The composition, as well as the length and temperature of the heat-treatment, must be carefully controlled to prevent solution of the precipitated tetragonal zirconia and subsequent conversion to the monoclinic phase.

  20. Colloid Zirconia Binder of Improved Wetting Properties

    Directory of Open Access Journals (Sweden)

    Grażyna Para

    2012-03-01

    Full Text Available Physicochemical properties of colloid zirconia aqueous sol, used as a binder in the investment casting industry, werethoroughly determined. The size of the particles was determined by dynamic light scattering, and the zeta potential of theparticles was measured by microelectrophoresis. The average size of the particles was 13 nm and the zeta potential waspositive, equal to 30 mV. The size distribution of particles deposited on mica surface was also determined using AFMmeasurements. The wetting properties of the binder suspension were determined for the paraffin/air interface using the shapeanalysis of pendant and sessile drops. The perfluorononanoic acid (PFNA, an anionic surfactant, the non-ionic fluorinatedsurfactants Zonyl FSO-100 and Rokafenol RN8, and the mixtures of the surfactants were studied. Our investigations showedthat the Zonyl-FSO surfactant and its mixture with Rokafenol effectively reduced the dynamic contact angle from the initialvalue of 94° to the value of 30°. Such low contact angles represent an essential improvement of zirconia binder wettability,thus widen the range of applicability in investment casting of finely shaped details.

  1. Development of a New Stretchable and Screen Printable Conductive Ink

    Science.gov (United States)

    Mohammed, Anwar A.

    Stretchable conductive ink is a key enabler for stretchable electronics. This thesis research focuses on the development of a new stretchable and screen printable conductive ink. After print and cure, this ink would be capable of being stretched by at least 500 cycles at 20% strain without increasing its resistance by more than 30 times the original resistance, while maintaining electrical and mechanical integrity. For a stretchable and screen-printable conductive ink, the correct morphology of the metal powder selected and the ability of the binder to be stretched after the sintering process, are both indispensable. This research has shown that a bi-modal mixture of fine and large-diameter silver flakes will improve stretchability. While the smaller flakes increase the conductivity and lower the sintering temperature, the larger flake particles promote ohmic connectivity during stretching. The bi-modal flake distribution increases connection points while enhancing packing density and lowering the thermal activation barrier. The polymer binder phase plays a crucial role in offering stretchability to the stretchable conductive inks. The silver flakes by themselves are not stretchable but they are contained within a stretchable binder system. The research demonstrates that commonly used printable ink binder when combined with large-chain polymers through a process known as 'elastomeric chain polymerization' will enable the conductive ink to become more stretchable. This research has shown that the new stretchable and screen printable silver conductive ink developed based upon the two insights mentioned above; (1) bi modal flakes to improve ohmic connectivity during stretching and (2) elastomeric chain polymerized binder system which could stretch even after the ink is sintered to the substrate, can exhibit an ink stretchability of at least 500 cycles at 20% strain while increasing the resistance by less than 30 times the original resistance. Wavy print patterns can

  2. Dopant ink composition and method of fabricating a solar cell there from

    Energy Technology Data Exchange (ETDEWEB)

    Loscutoff, Paul; Wu, Kahn; Molesa, Steven Edward

    2017-10-25

    Dopant ink compositions and methods of fabricating solar cells there from are described. A dopant ink composition may include a cross-linkable matrix precursor, a bound dopant species, and a solvent. A method of fabricating a solar cell may include delivering a dopant ink composition to a region above a substrate. The dopant ink composition includes a cross-linkable matrix precursor, a bound dopant species, and a solvent. The method also includes baking the dopant ink composition to remove a substantial portion of the solvent of the dopant ink composition, curing the baked dopant ink composition to cross-link a substantial portion of the cross-linkable matrix precursor of the dopant ink composition, and driving dopants from the cured dopant ink composition toward the substrate.

  3. Dopant ink composition and method of fabricating a solar cell there from

    Science.gov (United States)

    Loscutoff, Paul; Wu, Kahn; Molesa, Steven Edward

    2015-03-31

    Dopant ink compositions and methods of fabricating solar cells there from are described. A dopant ink composition may include a cross-linkable matrix precursor, a bound dopant species, and a solvent. A method of fabricating a solar cell may include delivering a dopant ink composition to a region above a substrate. The dopant ink composition includes a cross-linkable matrix precursor, a bound dopant species, and a solvent. The method also includes baking the dopant ink composition to remove a substantial portion of the solvent of the dopant ink composition, curing the baked dopant ink composition to cross-link a substantial portion of the cross-linkable matrix precursor of the dopant ink composition, and driving dopants from the cured dopant ink composition toward the substrate.

  4. Zirconia powders production by precipitation: state-of-art review

    International Nuclear Information System (INIS)

    Oliveira, Ana Paula Almeida de; Torem, Mauricio Leonardo

    1994-01-01

    The important role played by zirconia in advanced ceramics can be attributed to its excellent wear and corrosion resistance and refractory character. The polymorphic nature of zirconia made the controlled addition of stabilizing oxides or the constraining effect of a dense ceramics matrix necessary to maintain high parameters had a significant influence on powder properties and on compacted powder behaviour in sintering. Particle shape and size, purity and crystalline structure were specially influenced by precipitation parameters. Therefore, this work presented a review of the state of the art in zirconia powder production and in the recent research on precipitation of that powder. (author)

  5. The Use of Newer High Translucency Zirconia in Aesthetic Zone

    Directory of Open Access Journals (Sweden)

    Zishan Dangra

    2014-01-01

    Full Text Available Loss of anterior tooth causes aesthetic and functional disharmony. Although no restorative material can approach the appearance of intact tooth enamel, glass ceramic, at the increased risk of brittle fracture, can mimic original tooth color better than the other restorative options. The newest zirconia material comes with unparalleled individualization in aesthetics and optimal physical properties. One of the basic principles of tooth preparation is conservation of tooth structure. This clinical report describes the replacement of maxillary and mandibular incisor with latest generation zirconia adhesive fixed partial denture. The authors have achieved unmatched aesthetics with newer high translucency zirconia.

  6. Effects of the presence of heavy rare earths on the stabilization of the zirconia ceramics - Yttria; Efeito da presenca de terras raras pesadas na estabilizacao das fases de ceramicas de zirconia - itria

    Energy Technology Data Exchange (ETDEWEB)

    Lazar, D.R.R.; Fancio, E.; Menezes, C.A.B.; Ussui, V.; Bressiani, A.H.A.; Lima, N.B.; Paschoal, J.O.A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: drlazar@net.ipen.br

    2000-07-01

    The use of Yttria concentrates has been proposed to substitute the high purity Yttria in the zirconia stabilization. The elements terbium, dysprosium, holmium, erbium and ytterbium, classified as heavy rare earths, are the main impurities in these concentrates, due to their presence in yttrium ores. Besides that, the chemical similarities of these elements need the utilization of complex purification techniques. Considering the importance of the employed dopant on zirconia crystallization, this work shows the quantitative phases analysis of powders and ceramics of stabilized zirconia doped with 3 and 9 mol % of high purity Yttria and with a 85 wt % Yttria concentrate. This determination was performed using the Rietveld refinement of the X-ray diffraction data. The powders were synthesized by the hydroxides coprecipitation route, which includes treatments with ethanol and butanol, drying, calcination at 800 deg C for 1 hour and milling in a ball mill and in an attrition mill. The ceramics pellets were pressed uniaxially and sintered at 1550 deg C for 1 hour. The powders and sintered pellets were also characterized by X-ray fluorescence analysis, laser diffraction, gas adsorption (B.E.T.), scanning electron microscopy and determination of apparent density by the Archimedes method. The results showed the same stabilization behavior when it was employed high purity Yttria and a concentrate of this oxide. It was also observed the predominating formation of tetragonal and cubic phases when the dopant concentration is 3 and 9 mol %, respectively. (author)

  7. Microbiological evaluation of open and sealed tattoo inks

    Directory of Open Access Journals (Sweden)

    Lucia Bonadonna

    2014-12-01

    Full Text Available Background. Introduction of tattoo inks in the skin has been associated with a potential entry of a great number of microorganisms including bacteria, virus and fungi. Contaminated pigments, diluents and instruments represent primary infection risk factors as well as inadequacy of hygienic measures during this practice. However, the evaluation of the infectious risk for public health due to tattoo ink use is actually not feasible cause of the low efficiency of health surveillance and the lack of specific regulation in this area.Materials and Methods. A survey was carried out to test the microbial product safety of some tattoo inks available in Italian tattoo parlours. Physical packaging and labelling of the collected inks were also examined. Newly acquired sealed stock bottles, open ink bottles and tattoo-correlated instruments (needles, spikes and grips were collected and tested for different microbiological parameters. Results. Both from opened and sealed inks a variety of potentially pathogenic organisms were isolated and identified including Gram positive rods and cocci, Gram negative bacteria and fungi. Different species of Bacillus and Staphylococcus genera were identified, among which S. haemolyticus; Cronobacter sakazaki, Enterobacter intermedius and Sphingomonas paucimobilis were also identified while no atypical mycobacteria were isolated. Needles, spikes and grips tested for sterility were aseptic.Conclusions. Microbial contamination of opened samples suggest inefficacy of preservatives and additives in maintaining inks hygienic quality, and inadequacy of hygienic procedures during the tattooing operations, while the occurrence of microorganisms in unopened samples put in doubt the effectiveness of the sterilization technology applied to this type of product.

  8. Are zirconia corrosion films a form of partially stabilised zirconia (PSZ)?

    International Nuclear Information System (INIS)

    Cox, B.

    1987-03-01

    The problem of understanding the development of porosity in a zirconium oxide film still under biaxial compression is discussed. The oxide film is compared with partially stabilised zirconia (PSZ) where stress induced transformation of tetragonal zirconia has been observed to lead to microcracking of the structure. The similarities between PSZ and the thermal oxide films formed on zirconium alloys are enumerated, and an hypothesis is proposed that can both explain the penetration of pores or microcracks in oxides on Zircaloy-2 to a point very close to the oxide/metal interface, and explain the observation that such a phenomenon does not occur in oxide films on Zr-2.5%Nb. This hypothesis could be tested by laser Raman spectroscopy on oxide films during growth at elevated temperatures. 87 refs

  9. On the interfacial fracture of porcelain/zirconia and graded zirconia dental structures.

    Science.gov (United States)

    Chai, Herzl; Lee, James J-W; Mieleszko, Adam J; Chu, Stephen J; Zhang, Yu

    2014-08-01

    Porcelain fused to zirconia (PFZ) restorations are widely used in prosthetic dentistry. However, their susceptibility to fracture remains a practical problem. The failure of PFZ prostheses often involves crack initiation and growth in the porcelain, which may be followed by fracture along the porcelain/zirconia (P/Z) interface. In this work, we characterized the process of fracture in two PFZ systems, as well as a newly developed graded glass-zirconia structure with emphases placed on resistance to interfacial cracking. Thin porcelain layers were fused onto Y-TZP plates with or without the presence of a glass binder. The specimens were loaded in a four-point-bending fixture with the thin porcelain veneer in tension, simulating the lower portion of the connectors and marginal areas of a fixed dental prosthesis (FDP) during occlusal loading. The evolution of damage was observed by a video camera. The fracture was characterized by unstable growth of cracks perpendicular to the P/Z interface (channel cracks) in the porcelain layer, which was followed by stable cracking along the P/Z interface. The interfacial fracture energy GC was determined by a finite-element analysis taking into account stress-shielding effects due to the presence of adjacent channel cracks. The resulting GC was considerably less than commonly reported values for similar systems. Fracture in the graded Y-TZP samples occurred via a single channel crack at a much greater stress than for PFZ. No delamination between the residual glass layer and graded zirconia occurred in any of the tests. Combined with its enhanced resistance to edge chipping and good esthetic quality, graded Y-TZP emerges as a viable material concept for dental restorations. Copyright © 2014 Acta Materialia Inc. All rights reserved.

  10. Transparent Conductive Ink for Additive Manufacturing

    Science.gov (United States)

    Patlan, X. J.; Rolin, T. D.

    2017-01-01

    NASA analyzes, tests, packages, and fabricates electrical, electronic, and electromechanical (EEE) parts. Nanotechnology is listed in NASA's Technology Roadmap as a key area to invest for further development.1 This research project focused on using nanotechnology to improve electroluminescent lighting in terms of additive manufacturing and to increase energy efficiency. Specifically, this project's goal was to produce a conductive but transparent printable ink that can be sprayed on any surface for use as one of the electrodes in electroluminescent device design. This innovative work is known as thick film dielectric electroluminescent (TDEL) technology. TDEL devices are used for "backlighting, illumination, and identification due to their tunable color output, scalability, and efficiency" (I.K. Small, T.D. Rolin, and A.D. Shields, "3D Printed Electroluminescent Light Panels," NASA Fiscal Year 2017 Center Innovation Fund Proposal, unpublished data, 2017). These devices use a 'front-to-back' printing method, where the substrate is the transparent layer, and the dielectric and phosphor are layered on top. This project is a first step in the process of creating a 3D printable 'back-to-front' electroluminescent device. Back-to-front 3D-printed devices are beneficial because they can be printed onto different substrates and embedded in different surfaces, and the substrate is not required to be transparent, all because the light is emitted from the top surface through the transparent conductor. Advances in this area will help further development of printing TDEL devices on an array of different surfaces. Figure 1 demonstrates the layering of the two electrodes that are aligned in a parallel plate capacitor structure (I.K. Small, T.D. Rolin, and A.D. Shields, "3D Printed Electroluminescent Light Panels," NASA Fiscal Year 2017 Center Innovation Fund Proposal, unpublished data, 2017). Voltage is applied across the device, and the subsequent electron excitation results in

  11. Characterization of combustion synthesized zirconia powder by UV

    Indian Academy of Sciences (India)

    . The surface acidbase properties of these samples were also investigated by indicator titration method. The catalytic activity was probed with transfer hydrogenation reaction in liquid phase. It was found that combustion synthesized zirconia did ...

  12. Dehydration and crystallization kinetics of zirconia-yttria gels

    International Nuclear Information System (INIS)

    Ramanathan, S.; Muraleedharan, R.V.; Roy, S.K.; Nayar, P.K.K.

    1995-01-01

    Zirconia and zirconia-yttria gels containing 4 and 8 mol% yttria were obtained by coprecipitation and drying at 373 K. The dehydration and crystallization behavior of the dried gels was studied by DSC, TG, and XRD. The gels undergo elimination of water over a wide temperature range of 373--673 K. The peak temperature of the endotherm corresponding to dehydration and the kinetic constants for the process were not influenced by the yttria content of the gel. The enthalpy of dehydration observed was in good agreement with the heat of vaporization data. The dehydration was followed by a sharp exothermic crystallization process. The peak temperature of the exotherm and the activation energy of the process increased with an increase in yttria content, while the enthalpy of crystallization showed a decrease. The ''glow effect'' reduced with increasing yttria content. Pure zirconia crystallizes in the tetragonal form while the zirconia containing 4 and 8 mol% yttria appears to crystallize in the cubic form

  13. HRTEM investigation of phase stability in alumina–zirconia ...

    Indian Academy of Sciences (India)

    tries, at high temperatures, the small diffusion lengths involved can influence the phase stability. The present work ... a function of nanocrystalline size has been shown by Shukla ... and zirconia on a Si(100) single crystal substrate with differ-.

  14. The Use of Conductive Ink in Antenna Education and Design

    Science.gov (United States)

    Addison, David W.

    Conductive ink from a printer allows for the fabrication of conductive material with tight tolerances without the cost and time of chemical etching. This paper explores the use of AGIC printable conductive ink on a paper substrate as design tool for antennas as well as classroom use in antenna education. The antenna designs satisfy the requirements of a compact Global Navigation Satellite System (GNSS) antenna while showing a competitive performance within the current market. One best design is shown along with three other structures. These antennas consist of a bowtie cross-dipole over a reflective disc with conductive-ink grounded structures. In addition to the GNSS antennas, a linear elliptical dipole over a reflective disc with conductive grounded structures is presented. This elliptical antenna design attempts to find the maximum impedance bandwidth beyond the GNSS band. The inexpensive nature of conductive ink allows for its use in a classroom to demonstrate antenna behavior as part of antenna education. An inexpensive approach to the patch antenna using conductive ink is described and paired with a system made of off-the-shelf parts. The system is capable of measuring the power of the received signal. The received signal measurement is not as accurate as using a anechoic chamber but pattern details are visible. This is used to demonstrate aspects of the Friis transmission equation such as distance, polarization, radiation pattern shape, and loss.

  15. Photocytotoxicity in human dermal fibroblasts elicited by permanent makeup inks containing titanium dioxide.

    Science.gov (United States)

    Wamer, Wayne G; Yin, Jun-Jie

    2011-01-01

    Titanium dioxide (TiO2) is a pigment widely used in decorative tattoo and permanent makeup inks. However, little is known about the risks associated with its presence in these products. We have developed an in vitro assay to identify inks containing TiO2 that are cytotoxic and/or photocytotoxic. The presence of TiO2 in ten permanent makeup inks was established by X-ray fluorescence. Using X-ray diffraction, we found that seven inks contained predominately TiO2 (anatase), the more photocatalytically active crystalline form of TiO2. The remaining inks contained predominately TiO2 (rutile). To identify cytotoxic and/or photocytotoxic inks, human dermal fibroblasts were incubated for 18 h in media containing inks or pigments isolated from inks. Fibroblasts were then irradiated with 10 J/cm2 UVA radiation combined with 45 J/cm2 visible light for determining photocytotoxicity, or kept in the dark for determining cytotoxicity. Toxicity was assessed as inhibition of colony formation. No inks were cytotoxic. However eight inks, and the pigments isolated from these inks, were photocytotoxic. Using ESR, we found that most pigments from photocytotoxic inks generated hydroxyl radicals when photoexcited with UV radiation. Therefore, the possibility of photocytotoxicity should be considered when evaluating the safety of permanent makeup inks containing TiO2.

  16. Bonding effectiveness to different chemically pre-treated dental zirconia.

    Science.gov (United States)

    Inokoshi, Masanao; Poitevin, André; De Munck, Jan; Minakuchi, Shunsuke; Van Meerbeek, Bart

    2014-09-01

    The objective of this study was to evaluate the effect of different chemical pre-treatments on the bond durability to dental zirconia. Fully sintered IPS e.max ZirCAD (Ivoclar Vivadent) blocks were subjected to tribochemical silica sandblasting (CoJet, 3M ESPE). The zirconia samples were additionally pre-treated using one of four zirconia primers/adhesives (Clearfil Ceramic Primer, Kuraray Noritake; Monobond Plus, Ivoclar Vivadent; Scotchbond Universal, 3M ESPE; Z-PRIME Plus, Bisco). Finally, two identically pre-treated zirconia blocks were bonded together using composite cement (RelyX Ultimate, 3M ESPE). The specimens were trimmed at the interface to a cylindrical hourglass and stored in distilled water (7 days, 37 °C), after which they were randomly tested as is or subjected to mechanical ageing involving cyclic tensile stress (10 N, 10 Hz, 10,000 cycles). Subsequently, the micro-tensile bond strength was determined, and SEM fractographic analysis performed. Weibull analysis revealed the highest Weibull scale and shape parameters for the 'Clearfil Ceramic Primer/mechanical ageing' combination. Chemical pre-treatment of CoJet (3M ESPE) sandblasted zirconia using Clearfil Ceramic Primer (Kuraray Noritake) and Monobond Plus (Ivoclar Vivadent) revealed a significantly higher bond strength than when Scotchbond Universal (3M ESPE) and Z-PRIME Plus (Bisco) were used. After ageing, Clearfil Ceramic Primer (Kuraray Noritake) revealed the most stable bond durability. Combined mechanical/chemical pre-treatment, the latter with either Clearfil Ceramic Primer (Kuraray Noritake) or Monobond Plus (Ivoclar Vivadent), resulted in the most durable bond to zirconia. As a standard procedure to durably bond zirconia to tooth tissue, the application of a combined 10-methacryloyloxydecyl dihydrogen phosphate/silane ceramic primer to zirconia is clinically highly recommended.

  17. Characteristics of nanosized zirconia prepared by plasma and chemical technique

    International Nuclear Information System (INIS)

    Kuznetsova, L.; Grabis, J.; Heidemane, G.

    2003-01-01

    The studied preparation method of zirconia using the plasma technique, azeotropic distillation and glycine routes ensure obtaining of nano sized powders with close average particle size but different crystallite size and phase composition. The sinterability of nano sized zirconia particles prepared by plasma technique or wet-chemical methods is similar and depends on the green density of pressed powders, improvement of with can be achieved by using of granulated precursors. (authors)

  18. Structural and Chemical Analysis of the Zirconia-Veneering Ceramic Interface.

    Science.gov (United States)

    Inokoshi, M; Yoshihara, K; Nagaoka, N; Nakanishi, M; De Munck, J; Minakuchi, S; Vanmeensel, K; Zhang, F; Yoshida, Y; Vleugels, J; Naert, I; Van Meerbeek, B

    2016-01-01

    The interfacial interaction of veneering ceramic with zirconia is still not fully understood. This study aimed to characterize morphologically and chemically the zirconia-veneering ceramic interface. Three zirconia-veneering conditions were investigated: 1) zirconia-veneering ceramic fired on sandblasted zirconia, 2) zirconia-veneering ceramic on as-sintered zirconia, and 3) alumina-veneering ceramic (lower coefficient of thermal expansion [CTE]) on as-sintered zirconia. Polished cross-sectioned ceramic-veneered zirconia specimens were examined using field emission gun scanning electron microscopy (Feg-SEM). In addition, argon-ion thinned zirconia-veneering ceramic interface cross sections were examined using scanning transmission electron microscopy (STEM)-energy dispersive X-ray spectrometry (EDS) at high resolution. Finally, the zirconia-veneering ceramic interface was quantitatively analyzed for tetragonal-to-monoclinic phase transformation and residual stress using micro-Raman spectroscopy (µRaman). Feg-SEM revealed tight interfaces for all 3 veneering conditions. High-resolution transmission electron microscopy (HRTEM) disclosed an approximately 1.0-µm transformed zone at sandblasted zirconia, in which distinct zirconia grains were no longer observable. Straight grain boundaries and angular grain corners were detected up to the interface of zirconia- and alumina-veneering ceramic with as-sintered zirconia. EDS mapping disclosed within the zirconia-veneering ceramic a few nanometers thick calcium/aluminum-rich layer, touching the as-sintered zirconia base, with an equally thick silicon-rich/aluminum-poor layer on top. µRaman revealed t-ZrO2-to-m-ZrO2 phase transformation and residual compressive stress at the sandblasted zirconia surface. The difference in CTE between zirconia- and the alumina-veneering ceramic resulted in residual tensile stress within the zirconia immediately adjacent to its interface with the veneering ceramic. The rather minor chemical

  19. Defense through sensory inactivation: sea hare ink reduces sensory and motor responses of spiny lobsters to food odors.

    Science.gov (United States)

    Love-Chezem, Tiffany; Aggio, Juan F; Derby, Charles D

    2013-04-15

    Antipredator defenses are ubiquitous and diverse. Ink secretion of sea hares (Aplysia) is an antipredator defense acting through the chemical senses of predators by different mechanisms. The most common mechanism is ink acting as an unpalatable repellent. Less common is ink secretion acting as a decoy (phagomimic) that misdirects predators' attacks. In this study, we tested another possible mechanism--sensory inactivation--in which ink inactivates the predator's reception of food odors associated with would-be prey. We tested this hypothesis using spiny lobsters, Panulirus argus, as model predators. Ink secretion is composed of two glandular products, one being opaline, a viscous substance containing concentrations of hundreds of millimolar of total free amino acids. Opaline sticks to antennules, mouthparts and other chemosensory appendages of lobsters, physically blocking access of food odors to the predator's chemosensors, or over-stimulating (short term) and adapting (long term) the chemosensors. We tested the sensory inactivation hypotheses by treating the antennules with opaline and mimics of its physical and/or chemical properties. We compared the effects of these treatments on responses to a food odor for chemoreceptor neurons in isolated antennules, as a measure of effect on chemosensory input, and for antennular motor responses of intact lobsters, as a measure of effect on chemically driven motor behavior. Our results indicate that opaline reduces the output of chemosensors by physically blocking reception of and response to food odors, and this has an impact on motor responses of lobsters. This is the first experimental demonstration of inactivation of peripheral sensors as an antipredatory defense.

  20. Two R curves for partially stabilized zirconia

    International Nuclear Information System (INIS)

    Rose, L.R.F.; Swain, M.V.

    1986-01-01

    The enhanced fracture toughness due to stress-induced transformation can be explained from two view points: (1) the increase can be attributed to the need to supply a work of transformation, or (2) the transformation can be considered to result in internal stresses which oppose crack opening. Experimental results for magnesia-partially-stabilized zirconia are presented for the two experimental measures of toughness corresponding to these two viewpoints, namely (1) the specific work of fracture, R, and (2) the nominal stress intensity factor, K/sup R/. It is observed that these two measures are not equivalent during the initial stage of R-curve behavior, prior to reaching steady-state cracking. The theoretical reason for this difference is discussed. In particular, it is noted that the usual definition for the crack extension force does not correspond to the experimentally measured work of fracture in the presence of stress-induced (or pre-existing) sources of internal stress

  1. On transformation shear of precipitated zirconia particles

    International Nuclear Information System (INIS)

    Zhang, J.M.; Lam, K.Y.

    1993-01-01

    A model is proposed to investigate the transformation shear of the precipitated zirconia particles which undergo a stress-induced lattice transformation from tetragonal to monoclinic symmetry. Kinematically admissible twinning planes and the corresponding twinning elements are determined according to the continuum theory of dispacive phase transformation. It is postulated that only one twinning mode prevails in each transformed particle and that the minimization of elastic strain energy change dictates the morphology of the transformed variants. The transformation shear is determined by the twinning mode and the volume fraction of the corresponding variant. Numerical calculations show that each of the six kinematically admissible twinning modes may be kinematically favorable and therefore operate in constrained particle. The actual transformation shear in a transformed particle is shown to be dependent on the transformation stress, on the particle shape as well as on the lattice orientation relative to the principal axes of the ellipsoidal particle

  2. Ferroelastic domain switching in tetragonal zirconia

    International Nuclear Information System (INIS)

    Chan, C.J.; Ruhle, M.; Jue, J.F.; Virkar, A.V.

    1991-01-01

    Ferroelastic domain switching is one of the possible toughening mechanisms in ceramic materials. Microstructural evidence of domain reorientation (switching) in polydomain tetragonal zirconia single crystals is observed upon the application of a unidirectional compressive stress. Dark field imaging of the three (112) tetragonal twin variants in a [111] zone indicates that two sets of twin variants grow at the expense of the third set upon application of uniaxial compression. The diminishing variant is the one with its c axis parallel to the compression axis. Indentation experiments on uniaxially compressed samples show an anisotropy in crack length. Crack propogates more easily along the loading direction. In this paper construction for the orientation relationship of domains and their twin boundaries is presented

  3. Evaluation of advanced transformation toughened zirconia

    International Nuclear Information System (INIS)

    Swab, J.J.

    1986-01-01

    Transformation toughened zirconia (TTZ) is a material being considered for use in advanced heat engines. However, at elevated temperatures TTZ materials undergo a phase transformation from tetragonal to the monoclinic with an associated volume increase of approximately 5%. This transformation results in a loss of strength and fracture toughness. Six commercially available Japanese TTZ materials and one experimental domestic grade were examined for the extent and effect of this phase transformation after exposure to elevated temperatures (1000 to 1200 0 C) for times of 100 and 500 hours. Strength losses after heat treatment at 1000 0 C for 100 and 500 hours, ranged from a high of 60% to as little as 7%. Additional heat treatments of 500 hours at 1100 and 1200 0 C were carried out on TTZ's which had strength losses of 15% or less after exposure to 1000 0 C

  4. Properties of zirconia after plasma treatment

    Science.gov (United States)

    Alekseenko, V. P.; Kulkov, S. N.

    2017-09-01

    The influence of high-frequency plasma treatment on the properties of zirconia powder is shown in the work. The powder was produced by a plasma-chemical method. The powders had a foamy form with the size of agglomerates of 5-10 μm and crystallites of 20-50 nm. The powders were treated by the pulse plasma unit with dielectric barrier discharge generator. It was shown that the plasma processing changes the acidity of water-powder suspensions from 8.1 to 4.3 pH, which signifies the powders' wettability improvement. It was revealed that more intensive mixing using ultrasound influences the acidity level, reducing it in comparison with mixing by paddle-type agitator. It was shown that these changes of surface properties have relaxation by 4% per day and extrapolation of this dependence shows that the powder will have initial properties after 400 hours storage at room conditions.

  5. Synthesis and catalytic activity of polysaccharide templated nanocrystalline sulfated zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Sherly, K. B.; Rakesh, K. [Mahatma Gandhi University Regional Research Center in Chemistry, Department of Chemistry, Mar Athanasius College, Kothamangalam-686666, Kerala (India)

    2014-01-28

    Nanoscaled materials are of great interest due to their unique enhanced optical, electrical and magnetic properties. Sulfate-promoted zirconia has been shown to exhibit super acidic behavior and high activity for acid catalyzed reactions. Nanocrystalline zirconia was prepared in the presence of polysaccharide template by interaction between ZrOCl{sub 2}⋅8H{sub 2}O and chitosan template. The interaction was carried out in aqueous phase, followed by the removal of templates by calcination at optimum temperature and sulfation. The structural and textural features were characterized by powder XRD, TG, SEM and TEM. XRD patterns showed the peaks of the diffractogram were in agreement with the theoretical data of zirconia with the catalytically active tetragonal phase and average crystalline size of the particles was found to be 9 nm, which was confirmed by TEM. TPD using ammonia as probe, FTIR and BET surface area analysis were used for analyzing surface features like acidity and porosity. The BET surface area analysis showed the sample had moderately high surface area. FTIR was used to find the type species attached to the surface of zirconia. UV-DRS found the band gap of the zirconia was found to be 2.8 eV. The benzylation of o-xylene was carried out batchwise in atmospheric pressure and 433K temperature using sulfated zirconia as catalyst.

  6. Zirconia based dental ceramics: structure, mechanical properties, biocompatibility and applications.

    Science.gov (United States)

    Gautam, Chandkiram; Joyner, Jarin; Gautam, Amarendra; Rao, Jitendra; Vajtai, Robert

    2016-12-06

    Zirconia (ZrO 2 ) based dental ceramics have been considered to be advantageous materials with adequate mechanical properties for the manufacturing of medical devices. Due to its very high compression strength of 2000 MPa, ZrO 2 can resist differing mechanical environments. During the crack propagation on the application of stress on the surface of ZrO 2 , a crystalline modification diminishes the propagation of cracks. In addition, zirconia's biocompatibility has been studied in vivo, leading to the observation of no adverse response upon the insertion of ZrO 2 samples into the bone or muscle. In vitro experimentation has exhibited the absence of mutations and good viability of cells cultured on this material leading to the use of ZrO 2 in the manufacturing of hip head prostheses. The mechanical properties of zirconia fixed partial dentures (FPDs) have proven to be superior to other ceramic/composite restorations and hence leading to their significant applications in implant supported rehabilitations. Recent developments were focused on the synthesis of zirconia based dental materials. More recently, zirconia has been introduced in prosthetic dentistry for the fabrication of crowns and fixed partial dentures in combination with computer aided design/computer aided manufacturing (CAD/CAM) techniques. This systematic review covers the results of past as well as recent scientific studies on the properties of zirconia based ceramics such as their specific compositions, microstructures, mechanical strength, biocompatibility and other applications in dentistry.

  7. Synthesis, mechanical properties and bioactivity of nanostructured zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Debasish, E-mail: dsarkar@nitrkl.ac.in; Swain, Sanjaya Kumar; Adhikari, Sangeeta; Reddy, B. Sambi; Maiti, Himadri Sekhar, E-mail: hsmaiti2009@gmail.com

    2013-08-01

    Yttria stabilized zirconia 3Y – TZP nanopowders (10–30 nm) are prepared through direct precursor calcination of mixed zirconium oxychloride and yttrium nitrate solutions at 600 °C for 2 h. Cuboid(50 × 25 × 20 mm{sup 3}) zirconia blanks are fabricated through centrifuge casting and followed by sintering at 1350 °C for 2 h. Sintered zirconia blanks exhibit 24% volume shrinkage and 98% relative density with average grain size of 250 nm. Vickers hardness and indented fracture toughness of sintered blanks are measured as 13.5 GPa and 3.5 MPa.m{sup 1/2}, respectively. Bioactivity of nanostructured zirconia originates after four weeks incubation in simulated body fluid solution. An optimum time is required for the deposition of hydroxyapatite nanoparticles on stress-induced nucleation site of nanostructured zirconia. - Highlights: • A new technique has been proposed to prepare 10–30 nm 3Y – TZP nanopowders. • Cuboid zirconia blanks are fabricated through centrifuge casting. • Average grain size varies from 100 to 400 nm after sintering at 1350 °C for 2 h. • Hardness and fracture toughness are found as 13.5 GPa and 3.5 MPa.m{sup 1/2}, respectively. • Nanoscale hydroxyapatite deposits on stress-induced nucleation site of ZrO{sub 2} after optimum time.

  8. Natural radioactivity in zirconia-based dental ceramics

    International Nuclear Information System (INIS)

    Giussani, Augusto; Gerstmann, Udo; La Porta, Caterina; Cantone, Marie C.; Veronese, Ivan

    2008-01-01

    Zirconia-based ceramics are being increasingly used in dental prosthetics in substitution of metal cores, which are known to induce local toxic reactions and delayed allergic responses in the oral tissues. Some concerns have been however raised about the use of zirconia, since it is known that unpurified zirconia materials may contain non negligible levels of natural radionuclides of the U/Th series. Combined measurements of alpha and gamma spectrometry as well as beta dosimetry were conducted on zirconia samples used for dental applications. Samples were available in form of powder and/or solid blocks. The results showed that the beta dose rate in zirconia ceramics was on average only slightly higher than the levels measured in natural teeth, and generally lower than the values measured in feldspatic and glass ceramics. These materials are indeed known to deliver a beta dose significantly higher than that measured from natural teeth, due to the relatively high levels of 40 K (between 2 and 3 kBq·kg -1 ). The content of radionuclides of the U/Th series in the zirconia sample was estimated to be lower than 15 Bq·kg -1 , i.e. doubtlessly below the exclusion level of 1 kBq·kg -1 recommended by IAEA in the Safety Standard Series. Beta dosimetry measurements, however, gave indications of possible inhomogeneous clusters of radioactivity, which might give rise to local doses above the background. (author)

  9. Ultra-thin zirconia films on Zr-alloys

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Joong Il Jake; Mayr-Schmoelzer, Wernfried; Mittendorfer, Florian; Redinger, Josef; Diebold, Ulrike; Schmid, Michael [Institute of Applied Physics, Vienna University of Technology (Austria); Li, Hao; Rupprechter, Guenther [Institute of Materials Chemistry, Vienna University of Technology (Austria)

    2014-07-01

    Zirconia ultra-thin films have been prepared by oxidation of Pt{sub 3}Zr(0001) and showed a structure equivalent to (111) of cubic zirconia. Following previous work, we have prepared ultra-thin zirconia by oxidation of a different alloy, Pd{sub 3}Zr(0001), which resulted in a similar structure with a slightly different lattice parameter, 351.2 ±0.4 pm. Unlike the oxide on Pt{sub 3}Zr, where Zr of the oxide binds to Pt in the substrate, here the oxide binds to substrate Zr via oxygen. This causes stronger distortion of the oxide structure, i.e. a stronger buckling of Zr in the oxide. After additional oxidation of ZrO{sub 2}/Pt{sub 3}Zr, a different ultra-thin zirconia phase is observed. A preliminary structure model for this film is based on (113)-oriented cubic zirconia. 3D oxide clusters are also present after growing ultra-thin zirconia films. They occur at the step edges, and the density is higher on Pd{sub 3}Zr. These clusters also appear on terraces after additional oxidation. XPS reveals different core level shifts of the oxide films, bulk, and oxide clusters.

  10. Print Quality of Ink Jet Printed PVC Foils

    Directory of Open Access Journals (Sweden)

    Nemanja Kašiković

    2015-09-01

    Full Text Available Digital printing technique is used for a wide variety of substrates, one of which are PVC foils. Samples used in this research were printed by digital ink jet printing technique using Mimaki JV22 printing machine and J-Eco Subly Nano inks. As printing substrates, two different types of materials were used (ORACAL 640 - Print Vinyl and LG Hausys LP2712. A test card consisting of fields of CMYK colours was created and printed, varying the number of ink layers applied. Samples were exposed to light after the printing process. Spectrophotometric measurements were conducted before and after the light treatment. Based on spectrophotometricaly obtained data, colour differences ΔE2000 were calculated. Results showed that increasing number of layers, as well as the right choice of substrates, can improve the behaviour of printed product during exploitation.

  11. Silver nanoparticle ink technology: state of the art

    Directory of Open Access Journals (Sweden)

    Rajan K

    2016-01-01

    Full Text Available Krishna Rajan, Ignazio Roppolo, Annalisa Chiappone, Sergio Bocchini, Denis Perrone, Alessandro Chiolerio Center for Space Human Robotics, Italian Institute of Technology, Turin, Italy Abstract: Printed electronics will bring to the consumer level great breakthroughs and unique products in the near future, shifting the usual paradigm of electronic devices and circuit boards from hard boxes and rigid sheets into flexible thin layers and bringing disposable electronics, smart tags, and so on. The most promising tool to achieve the target depends upon the availability of nanotechnology-based functional inks. A certain delay in the innovation-transfer process to the market is now being observed. Nevertheless, the most widely diffused product, settled technology, and the highest sales volumes are related to the silver nanoparticle-based ink market, representing the best example of commercial nanotechnology today. This is a compact review on synthesis routes, main properties, and practical applications. Keywords: silver nanoparticles, surface plasmon resonance, nanocomposites, inks, printed electronics

  12. A Potential Adjuvant Agent of Chemotherapy: Sepia Ink Polysaccharides

    Directory of Open Access Journals (Sweden)

    Fangping Li

    2018-03-01

    Full Text Available Sepia ink polysaccharide (SIP isolated from squid and cuttlefish ink is a kind of acid mucopolysaccharide that has been identified in three types of primary structures from squid (Illex argentinus and Ommastrephes bartrami, cuttlefish Sepiella maindroni, and cuttlefish Sepia esculenta ink. Although SIP has been proved to be multifaceted, most of the reported evidence has illuminated its chemopreventive and antineoplastic activities. As a natural product playing a role in cancer treatment, SIP may be used as chemotherapeutic ancillary agent or functional food. Based on the current findings on SIP, we have summarized four topics in this review, including: chemopreventive, antineoplastic, chemosensitive, and procoagulant and anticoagulant activities, which are correlative closely with the actions of anticancer agents on cancer patients, such as anticancer, toxicity and thrombogenesis, with the latter two actions being common causes of death in cancer cases exposed to chemotherapeutic agents.

  13. Irradiation effects and behaviour of fission products in zirconia and spinel

    International Nuclear Information System (INIS)

    Gentils, A.

    2003-10-01

    Crystalline oxides, such as zirconia (ZrO 2 ) and spinel (MgAl 2 O 4 ), are promising inert matrices for the transmutation of plutonium and minor actinides. This work deals with the study of the physico-chemical properties of these matrices, more specifically their behaviour under irradiation and their capacity to retain fission products. Irradiations at low energy and incorporation of stable analogs of fission products (Cs, I, Xe) into yttria-stabilized zirconia and magnesium-aluminate spinel single crystals were performed by using the ion implanter IRMA (CSNSM-Orsay). Irradiations at high energy were made on several heavy ion accelerators (GANIL-Caen, ISL-Berlin, HIL-Warsaw). The damage induced by irradiation and the release of fission products were monitored by in situ Rutherford Backscattering Spectrometry experiments. Transmission electron microscopy was also used in order to determine the nature of the damage induced by irradiation. The results show that irradiation of ZrO 2 and MgAl 2 O 4 with heavy ions (about hundred keV and about hundred MeV) induces a huge structural damage in crystalline matrices. Total disorder (amorphization) is however never reached in zirconia, contrary to what is observed in the case of spinel. The results also emphasize the essential role played by the concentration of implanted species on their retention capacity. A dramatic release of fission products was observed when the concentration exceeds a threshold of a few atomic percent. Irradiation of implanted samples with medium-energy noble-gas ions leads to an enhancement of the fission product release. The exfoliation of spinel crystals implanted at high concentration of Cs ions is observed after a thermal treatment at high temperature. (author)

  14. Ink Penetration of Uncoated Inkjet Paper and Impact on Printing Quality

    Directory of Open Access Journals (Sweden)

    Ren'ai Li

    2015-10-01

    Full Text Available This study investigated ink penetration through imaging technology, first by gray and contour mapping and then calculating the ink penetration depth by programing. Next, a series of further analyses were carried out, including average ink permeability, ink distributions, and printability of different uncoated inkjet paper with different parameters. The impact on ink penetration of the microstructure and hydrophilicity of the uncoated paper was also studied. The experimental results indicated that paper specimens with sizing agent were resistant to the ink, resulting in a slow and shallow ink penetration. Paper containing filler had a more hydrophilic surface and porous structure, leading to a faster and deeper ink penetration. However, the calendering operation could make the paper structure more compact and reduce the porosity and penetration depth. When an appropriate combination of sizing agent, filler content, and the calendering process was utilized, a more stable hue could be produced with improvements in optical density, saturation, and color.

  15. Sorption of uranyl species on zircon and zirconia

    International Nuclear Information System (INIS)

    Lomenech, C.; Drot, R.; Simoni, E.; Ehrhardt, J.J.; Mielczarski, J.

    2002-01-01

    The safety of a long-term storage of radioactive waste in deep geological repositories would be strongly affected by the migration properties of radionuclides through the different barriers to the surface of the earth. Since the main process involved in the retention of radioactive ions is their sorption at the water/ mineral interface, a quantitative description of the sorption reactions is needed. Macroscopic data have for a long time been the only source of information used to propose a modelling of sorption equilibria, although they bring no direct information on the nature of the sorbed species; a microscopic structural investigation of the surface complexes is difficult indeed, because of the small amount of matter sorbed. Thus, in this study, parallel to the macroscopic measurements, different complementary spectroscopic techniques have been used in order to determine the nature of the surface species. As the final purpose of such a study is the simulation of the experimental retention data, the precise structural identification of the sorption equilibria will then be very useful to constrain the data simulation code. In this work, we present the results of both macroscopic and microscopic studies of the sorption of uranyl species on zircon and zirconia. The first part of our macroscopic approach was the surface characterisation of the non-sorbed materials by the determination of the specific areas, of the pH of the isoelectric points, and of the sorption site numbers, while the second part aimed at obtaining the sorption isotherms (percentage of sorption versus pH), which was performed using alpha spectrometry, for different uranyl concentrations, media (NaClO 4 or KNO 3 ) and ionic strengths. The spectroscopic identification of the different surface complexes and sorption sites has been carried out using four different spectroscopies. Whereas tune-resolved laser spectro-fluorimetry gave a direct answer concerning the number of surface species (only for a

  16. The Influence of Parameters of Ink-Jet Printing on Photoluminescence Properties of Nanophotonic Labels Based on Ag Nanoparticles for Smart Packaging

    Directory of Open Access Journals (Sweden)

    Olha Hrytsenko

    2017-01-01

    Full Text Available Ag nanoparticles are perspective for the use in ink-jet printed smart packaging labels in order to protect a customer from counterfeit or inform them about the safety of consumption of a packaged product via changeable luminescence properties. It is determined that, to obtain printed images with the highest luminescence intensity, using the most technologically permissible concentration of fluorescent component in the ink composition and applying inks to papers with the lowest absorbance are recommended. The highest contrast of a tone fluorescent image can be obtained on papers with high degree of sizing. It is found that the use of papers with low optical brightness agent (OBA content with a wide range of luminescence intensity allows obtaining the same visual legibility of a printed nanophotonic label. The increase in the relative area of raster elements of an image leads to nonlinear increase in luminescence intensity of printed images in long-wave area of visible spectrum, affecting the luminescence color of a printed label. For wide industrial production of printed nanophotonic labels for smart packaging, the created principles of reproduction of nanophotonic images applied onto paper materials by ink-jet printing technique using printing inks containing Ag nanoparticles should be taken into account.

  17. External PIXE analysis of old inks and papers

    International Nuclear Information System (INIS)

    Hassanzadeh, A.; Lamehi-Rachti, M.; Oliaiy, P.; Rahighi, J.; Shokouhi, F.

    1999-01-01

    Proton Induced X-ray Emission, PIXE is a very well established analytical method. This technique of analysis can equally be applied both in vacuum, internal PIXE, and in atmosphere, external PIXE. External PIXE has been applied to material analysis in Van de Graaff laboratory at AEOI using filters and funny filters. Advantages of using these filters have been studied when analysing ancient written documents such as envelopes, inks, and newspapers. This technique clearly demonstrated the differences between new and old inks and papers. More data is needed to show other features of this technique. (author)

  18. Microbial status and product labelling of 58 original tattoo inks

    DEFF Research Database (Denmark)

    Høgsberg, T; Saunte, D M; Frimodt-møller, Niels

    2011-01-01

    and labelled according to REACH as if they were plain chemicals. Objective  The objective of this study was to check the microbial product safety of unopened and opened tattoo ink stock bottles. Packaging, labelling, preservation, sterility and contamination with micro-organisms were studied. Methods  Physical......-pathogenic environmental bacteria. Yeast or moulds were detected in none of the samples. A total of 31% of the manufacturers informed only about the brand name. No information about content, sterility, risks or expiry date was indicated on the label. A total of 42% claimed sterility of their inks. A total of 54% labelled...

  19. Pigments and oligomers for inks - moving towards the best combination

    International Nuclear Information System (INIS)

    Hutchinson, I.; Smith, S.; Grierson, W.; Devine, E.

    1999-01-01

    The formulation of UV curable printing inks depends on several complex factors. If the individual components of the ink are not complementary, then performance problems can arise. One critical combination is that between the pigment and the oligomer. In a new approach to improve understanding of pigment/oligomer interactions, the resources of a pigment manufacturer and an oligomer manufacturer have been combined to investigate the problem. Initial screening of process yellow pigments and several oligomer types highlighted performance variations which were then examined in more detail

  20. 49 CFR 173.173 - Paint, paint-related material, adhesives, ink and resins.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Paint, paint-related material, adhesives, ink and... Than Class 1 and Class 7 § 173.173 Paint, paint-related material, adhesives, ink and resins. (a) When..., paint-related material, adhesives, ink and resins must be packaged as follows: (1) As prescribed in...

  1. Applicability of surface-enhanced resonance Raman scattering for the direct discrimination of ballpoint pen inks

    NARCIS (Netherlands)

    Seifar, R.M.; Verheul, J.M.; Ariese, F.; Brinkman, U.A.T.; Gooijer, C.

    2001-01-01

    In situ surface-enhanced resonance Raman spectroscopy (SERRS) with excitation at 685 nm is suitable for the direct discrimination of blue and black ballpoint pen inks on paper. For black inks, shorter excitation wavelengths can also be used. For blue inks, SERRS at 514.5 and 457.9 nm does not

  2. Translucency of Zirconia Ceramics before and after Artificial Aging.

    Science.gov (United States)

    Walczak, Katarzyna; Meißner, Heike; Range, Ursula; Sakkas, Andreas; Boening, Klaus; Wieckiewicz, Mieszko; Konstantinidis, Ioannis

    2018-03-11

    The aging of zirconia ceramics (Y-TZP) is associated with tetragonal to monoclinic phase transformation. This change in microstructure may affect the optical properties of the ceramic. This study examines the effect of aging on the translucency of different zirconia materials. 120 disc-shaped specimens were fabricated from four zirconia materials: Cercon ht white, BruxZir Solid Zirconia, Zenostar T0, Lava Plus (n = 30 per group). Accelerated aging was performed in a steam autoclave (134°C, 0.2 MPa, 5 hours). CIELab coordinates (L*, a*, b*) and luminous reflectance (Y) were measured with a spectrophotometer before and after aging. Contrast ratio (CR) and translucency parameter (TP) were calculated from the L*, a*, b*, and Y tristimulus values. The general linear model (Bonferroni adjusted) was used to compare both parameters before and after aging, as well as between the different zirconia materials (p ≤ 0.05). CR and TP differed significantly before and after aging in all groups tested. Before aging, Zenostar T showed the highest and Lava Plus showed the lowest translucency. After aging, Cercon ht and Zenostar T showed the highest and BruxZir and Lava Plus the lowest translucency. Aging reduced the translucency in all specimens tested. Furthermore, translucency differed between the zirconia brands tested. Nevertheless, the differences were below the detectability threshold of the human eye. The aging process can influence the translucency and thus the esthetic outcome of zirconia restorations; however, the changes in translucency were minimal and probably undetectable by the human eye. © 2018 by the American College of Prosthodontists.

  3. Orthodontic bracket bonding to glazed full-contour zirconia

    Directory of Open Access Journals (Sweden)

    Ji-Young Kwak

    2016-05-01

    Full Text Available Objectives This study evaluated the effects of different surface conditioning methods on the bond strength of orthodontic brackets to glazed full-zirconia surfaces. Materials and Methods Glazed zirconia (except for the control, Zirkonzahn Prettau disc surfaces were pre-treated: PO (control, polishing; BR, bur roughening; PP, cleaning with a prophy cup and pumice; HF, hydrofluoric acid etching; AA, air abrasion with aluminum oxide; CJ, CoJet-Sand. The surfaces were examined using profilometry, scanning electron microscopy, and electron dispersive spectroscopy. A zirconia primer (Z-Prime Plus, Z or a silane primer (Monobond-S, S was then applied to the surfaces, yielding 7 groups (PO-Z, BR-Z, PP-S, HF-S, AA-S, AA-Z, and CJ-S. Metal bracket-bonded specimens were stored in water for 24 hr at 37℃, and thermocycled for 1,000 cycles. Their bond strengths were measured using the wire loop method (n = 10. Results Except for BR, the surface pre-treatments failed to expose the zirconia substructure. A significant difference in bond strengths was found between AA-Z (4.60 ± 1.08 MPa and all other groups (13.38 ± 2.57 - 15.78 ± 2.39 MPa, p < 0.05. For AA-Z, most of the adhesive remained on the bracket. Conclusions For bracket bonding to glazed zirconia, a simple application of silane to the cleaned surface is recommended. A zirconia primer should be used only when the zirconia substructure is definitely exposed.

  4. Paper-based maskless enzymatic sensor for glucose determination combining ink and wire electrodes.

    Science.gov (United States)

    Amor-Gutiérrez, O; Costa Rama, E; Costa-García, A; Fernández-Abedul, M T

    2017-07-15

    In this work we have developed an amperometric enzymatic biosensor in a paper-based platform with a mixed electrode configuration: carbon ink for the working electrode (WE) and metal wires (from a low-cost standard electronic connection) for reference (RE) and auxiliary electrodes (AE). A hydrophobic wax-defined paper area was impregnated with diluted carbon ink. Three gold-plated pins of the standard connection are employed, one for connecting the WE and the other two acting as RE and AE. The standard connection works as a clip in order to support the paper in between. As a proof-of-concept, glucose sensing was evaluated. The enzyme cocktail (glucose oxidase, horseradish peroxidase and potassium ferrocyanide as mediator of the electron transfer) was adsorbed on the surface. After drying, glucose solution was added to the paper, on the opposite side of the carbon ink. It wets RE and AE, and flows by capillarity through the paper contacting the carbon WE surface. The reduction current of ferricyanide, product of the enzymatic reaction, is measured chronoamperometrically and correlates to the concentration of glucose. Different parameters related to the bioassay were optimized, adhering the piece of paper onto a conventional screen-printed carbon electrode (SPCE). In this way, the RE and the AE of the commercial card were employed for optimizing the paper-WE. After evaluating the assay system in the hybrid paper-SPCE cell, the three-electrode system consisting of paper-WE, wire-RE and wire-AE, was employed for glucose determination, achieving a linear range between 0.3 and 15mM with good analytical features and being able of quantifying glucose in real food samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Writer identification using directional ink-trace width measurements

    NARCIS (Netherlands)

    Brink, A. A.; Smit, J.; Bulacu, M. L.; Schomaker, L. R. B.

    As suggested by modern paleography, the width of ink traces is a powerful source of information for off-line writer identification, particularly if combined with its direction. Such measurements can be computed using simple, fast and accurate methods based on pixel contours, the combination of which

  6. Antifungal and Antihepatotoxic Effects of Sepia Ink Extract against ...

    African Journals Online (AJOL)

    Background: There is a great need for novel strategies to overcome the high mortality associated with invasive pulmonary aspergillosis (IPA) in immunocompromised patients. To evaluate the antifungal and antihepatotoxic potentials of Sepia ink extract, its effect on liver oxidative stress levels was analyzed against IPA in ...

  7. In search of the rainbow: Colored inks in surgical pathology

    Directory of Open Access Journals (Sweden)

    Chandralekha Tampi

    2012-01-01

    Full Text Available Introduction: Although surgical pathologists are aware of the multiple advantages that coloured inks contribute to surgical pathology practice, these coloured inks are not available in India and importing them is not a viable proposition. A systematic search for locally available coloring agents was done, and resulted in identifying specific shades within a popular set of children′s hobby colors of a particular brand. They retain their bright distinct colors on paraffin blocks and sections. These paints are available all over India, and are cheap, safe, and easy to use. Coloring gross specimen excision margins with different colors, adds precision to margin examination. It allows three-dimensional microscopic reconstruction of the tumor vis-a-vis its various neighboring anatomic structures. It allows postoperative comparison of tissue planes predicted by preoperative imaging. It maintains orientation of grossed and dissected specimens, enabling the pathologist to re-visit the grossed specimen, if required, and confidently allows further sampling if necessary. Aim: A systematic search for indigenous coloring agents was carried out, which included the dyes used in the histopathology laboratory, gelatin, commercially available paints, including acrylic paints and inks. Results: The study identified specific shades within a brand of acrylic colors that are easily available and simple to use, with good results on microscopic examination. Conclusion: Colored inks lend precision to margin examination. A set of easily procurable colors are available in our country, which are easy to use, with distinct bright colors, safe, and reliable.

  8. The Sneaky Sneaker Spies and the Mysterious Black Ink

    Science.gov (United States)

    Savran, Michelle

    2012-01-01

    In this article, the author describes the process of making "The Sneaky Sneaker Spies and the Mysterious Black Ink," a six-minute animation starring five art students who form a detective club. This animation is available online for art teachers to use in their own classrooms. After showing this video in class, art teachers could have students try…

  9. Radiation cure technology used in inks and coatings

    International Nuclear Information System (INIS)

    Ravijst, J.-P.

    1995-01-01

    The radiation cure technology in inks and coatings by ultraviolet light (UV) and electron beam (EB) was introduced. The technology is the only one which meets the 3-E rules. An advantage of this technology is that a wide range of substrates can be printed such as paper, card, metal and even heat sensitive plastics

  10. Ridge Width Correlations between Inked Prints and Powdered Latent Fingerprints.

    Science.gov (United States)

    De Alcaraz-Fossoul, Josep; Barrot-Feixat, Carme; Zapico, Sara C; Mancenido, Michelle; Broatch, Jennifer; Roberts, Katherine A; Carreras-Marin, Clara; Tasker, Jack

    2017-10-03

    A methodology to estimate the time of latent fingerprint deposition would be of great value to law enforcement and courts. It has been observed that ridge topography changes as latent prints age, including the widths of ridges that could be measured as a function of time. Crime suspects are commonly identified using fingerprint databases that contain reference inked tenprints (flat and rolled impressions). These can be of interest in aging studies as they provide baseline information relating to the original (nonaged) ridges' widths. In practice, the age of latent fingerprints could be estimated following a comparison process between the evidentiary aged print and the corresponding reference inked print. The present article explores possible correlations between inked and fresh latent fingerprints deposited on different substrates and visualized with TiO 2 . The results indicate that the ridge width of flat inked prints is most similar to fresh latent fingerprints , and these should be used as the comparison standard for future aging studies. © 2017 American Academy of Forensic Sciences.

  11. INK AND CLEANER WASTE REDUCTION EVALUATION FOR FLEXOGRAPHIC PRINTERS

    Science.gov (United States)

    This report describes the technical and economic effects incurred by a flexographic label printer who changed the type of ink and cleaning agent used in its print shop. The changes were incurred as the best way to eliminate all hazardous materials. The company's corporate managem...

  12. Ink and Wash Painting for Children with Visual Impairment

    Science.gov (United States)

    Shih, Chih-Ming; Chao, Hsin-Yi

    2010-01-01

    Five children with visual impairments received instruction in drawing, using ink and wash painting and calligraphy techniques. A special system developed by a blind Taiwanese Chinese calligrapher, Tsann-Cherng Liaw, was used to help the children orient and refine their work. Children's performance on simple drawing tasks was compared before and…

  13. Zirconia changes after grinding and regeneration firing.

    Science.gov (United States)

    Hatanaka, Gabriel R; Polli, Gabriela S; Fais, Laiza M G; Reis, José Maurício Dos S N; Pinelli, Lígia A P

    2017-07-01

    Despite improvements in computer-aided design and computer-aided manufacturing (CAD-CAM) systems, grinding during either laboratory procedures or clinical adjustments is often needed to modify the shape of 3 mol(%) yttria-tetragonal zirconia polycrystal (3Y-TZP) restorations. However, the best way to achieve adjustment is unclear. The purpose of this in vitro study was to evaluate the microstructural and crystallographic phase changes, flexural strength, and Weibull modulus of a 3Y-TZP zirconia after grinding with or without water cooling and regeneration firing. Ninety-six bar-shaped specimens were obtained and divided as follows: as-sintered, control; as-sintered with regeneration firing; grinding without water cooling; grinding and regeneration firing with water cooling; and grinding and regeneration firing. Grinding (0.3 mm) was performed with a 150-μm diamond rotary instrument in a high-speed handpiece. For regeneration firing, the specimens were annealed at 1000°C for 30 minutes. The crystalline phases were evaluated by using x-ray powder diffraction. A 4-point bending test was conducted (10 kN; 0.5 mm/min). The Weibull modulus was used to analyze strength reliability. The microstructure was analyzed by scanning electron microscopy. Data from the flexural strength test were evaluated using the Kruskal-Wallis and Dunn tests (α=.05). Tetragonal-to-monoclinic phase transformation was identified in the ground specimens; R regeneration firing groups showed only the tetragonal phase. The median flexural strength of as-sintered specimens was 642.0; 699.3 MPa for as-sintered specimens with regeneration firing; 770.1 MPa for grinding and water-cooled specimens; 727.3 MPa for specimens produced using water-cooled grinding and regeneration firing; 859.9 MPa for those produced by grinding; and 764.6 for those produced by grinding and regeneration firing; with statistically higher values for the ground groups. The regenerative firing did not affect the flexural

  14. Influence of framework color and layering technique on the final color of zirconia veneered restorations

    NARCIS (Netherlands)

    Aboushelib, M.N.; Dozic, A.; Liem, J.K.

    2010-01-01

    Objective: To investigate the influence of colored zirconia frameworks on the overall color match of zirconia- veneered restorations. Method and Materials: Identical natural and colored zirconia frameworks (Cercon Base, Degudent) were layered using a veneer ceramic (IPS e.max Ceram Dentin, Ivoclar

  15. CAD/CAM Zirconia vs. slip-cast glass-infiltrated Alumina/Zirconia all-ceramic crowns: 2-year results of a randomized controlled clinical trial

    Directory of Open Access Journals (Sweden)

    Murat Cavit Çehreli

    2009-02-01

    Full Text Available The aim of this randomized controlled clinical trial was to compare the early clinical outcome of slip-cast glass-infiltrated Alumina/Zirconia and CAD/CAM Zirconia all-ceramic crowns. A total of 30 InCeram® Zirconia and Cercon® Zirconia crowns were fabricated and cemented with a glass ionomer cement in 20 patients. At baseline, 6-month, 1-year, and 2-year recall appointments, Californian Dental Association (CDA quality evaluation system was used to evaluate the prosthetic replacements, and plaque and gingival index scores were used to explore the periodontal outcome of the treatments. No clinical sign of marginal discoloration, persistent pain and secondary caries was detected in any of the restorations. All InCeram® Zirconia crowns survived during the 2-year period, although one nonvital tooth experienced root fracture coupled with the fracture of the veneering porcelain of the restoration. One Cercon® Zirconia restoration fractured and was replaced. According to the CDA criteria, marginal integrity was rated excellent for InCeram® Zirconia (73% and Cercon® Zirconia (80% restorations, respectively. Slight color mismatch rate was higher for InCeram® Zirconia restorations (66% than Cercon® Zirconia (26% restorations. Plaque and gingival index scores were mostly zero and almost constant over time. Time-dependent changes in plaque and gingival index scores within and between groups were statistically similar (p>0.05. This clinical study demonstrates that single-tooth InCeram® Zirconia and Cercon® Zirconia crowns have comparable early clinical outcome, both seem as acceptable treatment modalities, and most importantly, all-ceramic alumina crowns strengthened by 25% zirconia can sufficiently withstand functional load in the posterior zone.

  16. Study of the creep of lime-stabilised zirconia

    International Nuclear Information System (INIS)

    Saint-Jacques, Robert G.

    1971-09-01

    This research thesis reports the study of creep of stabilised zirconia containing between 13 and 20 per cent of lime, at temperatures between 1.200 and 1.400 C, and under compression stresses between 500 and 4.000 pounds by square inch. Specimens are polycrystalline with an average grain diameter between 7 and 29 microns. The author notably shows that the creep rate of lime-stabilised zirconia is directly proportional to the applied stress, and that the creep apparent activation energy is close to activation energy of volume self-diffusion of calcium and zirconium in lime-stabilised zirconia. Results of creep tests show that, in the studied conditions, the creep rate is directly proportional to the inverse of the grain average diameter, and this is in compliance with the Gifkins and Snowden theory of creep by sliding at grain boundaries. The author also shows that the creep rate of the lime stabilised zirconia varies with lime content, and reaches a maximum when zirconia contains about 15 per cent of lime. Lower creep rates obtained for higher and lower lime contents are explained [fr

  17. Corrosion behavior of zirconia in acidulated phosphate fluoride

    Directory of Open Access Journals (Sweden)

    Anie Thomas

    2016-02-01

    Full Text Available ABSTRACT Objective The corrosion behavior of zirconia in acidulated phosphate fluoride (APF representing acidic environments and fluoride treatments was studied. Material and Methods Zirconia rods were immersed in 1.23% and 0.123% APF solutions and maintained at 37°C for determined periods of time. Surfaces of all specimens were imaged using digital microscopy and scanning electron microscopy (SEM. Sample mass and dimensions were measured for mass loss determination. Samples were characterized by powder X-ray diffraction (XRD to detect changes in crystallinity. A biosensor based on electrochemical impedance spectroscopy (EIS was used to detect ion dissolution of material into the immersion media. Results Digital microscopy revealed diminishing luster of the materials and SEM showed increased superficial corrosion of zirconia submerged in 1.23% APF. Although no structural change was found, the absorption of salts (sodium phosphate onto the surface of the materials bathed in 0.123% APF was significant. EIS indicated a greater change of impedance for the immersion solutions with increasing bathing time. Conclusion Immersion of zirconia in APF solutions showed deterioration limited to the surface, not extending to the bulk of the material. Inferences on zirconia performance in acidic oral environment can be elucidated from the study.

  18. Defect ordering in aliovalently doped cubic zirconia from first principles

    International Nuclear Information System (INIS)

    Bogicevic, A.; Wolverton, C.; Crosbie, G.M.; Stechel, E.B.

    2001-01-01

    Defect ordering in aliovalently doped cubic-stabilized zirconia is studied using gradient corrected density-functional calculations. Intra- and intersublattice ordering interactions are investigated for both cation (Zr and dopant ions) and anion (oxygen ions and vacancies) species. For yttria-stabilized zirconia, the crystal structure of the experimentally identified, ordered compound δ-Zr 3 Y 4 O 12 is established, and we predict metastable zirconia-rich ordered phases. Anion vacancies repel each other at short separations, but show an energetic tendency to align as third-nearest neighbors along directions. Calculations with divalent (Be, Mg, Ca, Sr, Ba) and trivalent (Y, Sc, B, Al, Ga, In) oxides show that anion vacancies prefer to be close to the smaller of the cations (Zr or dopant ion). When the dopant cation is close in size to Zr, the vacancies show no particular preference, and are thus less prone to be bound preferentially to any particular cation type when the vacancies traverse such oxides. This ordering tendency offers insight into the observed high conductivity of Y 2 O 3 - and Sc 2 O 3 -stabilized zirconia, as well as recent results using, e.g., lanthanide oxides. The calculations point to In 2 O 3 as a particularly promising stabilizer for high ionic conductivity. Thus we are able to directly link (thermodynamic) defect ordering to (kinetic) ionic conductivity in cubic-stabilized zirconia using first-principles atomistic calculations

  19. Mechanical behavior of mullite-zirconia composites

    Directory of Open Access Journals (Sweden)

    Sahnoune F.

    2010-06-01

    Full Text Available In this work, mechanical properties of mullite–zirconia composites synthesised through reaction sintering of Algerian kaolin, α-Al2O3, and ZrO2 were characterized. Phases present and their transformations were characterized using x-ray diffraction. Hardness H and fracture toughness KIC were measured by Vickers indentation using a Zwick microhardness tester. The flexural strength was measured through three point bending test using an Instron Universal Testing Machine. It was found that the increase of ZrO2 content (from 0 to 32wt.% decreased the microhardness of the composites from 14 to 10.8 GPa. However, the increase of ZrO2 content (from 0 to 24wt.% increased the flexural strength of the composites from 142 to 390 MPa then decreased it with further increase of ZrO2 content. Also, the fracture toughness increased from 1.8 to 2.9 MPa.m1/2 with the increase of ZrO2 content from 0 to 32 wt.%; and the rate of the increase decreased at higher fractions of ZrO2 content. The average linear coefficient of thermal expansion (within the range 50 to 1450°C for samples containing 0 and 16 wt.% ZrO2 sintered at 1600°C for 2 hours was 4.7 x10-6 K-1 and 5.2 x 10-6 K-1 respectively.

  20. Fracture behaviour of zirconia FPDs substructures.

    Science.gov (United States)

    Kou, W; Sjögren, G

    2010-04-01

    The purpose of this study was to evaluate the occurrence of superficial flaws after machining and to identify fracture initiation and propagation in three-unit heat-treated machined fixed partial dentures (FPDs) substructures made of hot isostatic pressed (HIPed) yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) after loaded to fracture. Four three-unit HIPed Y-TZP-based FPDs substructures were examined. To evaluate the occurrence of superficial flaws after machining, the surfaces were studied utilizing a fluorescent penetrant method. After static loading to fracture, characteristic fracture features on both mating halves of the fractured specimens were studied using a stereomicroscope and a scanning electron microscope. Grinding grooves were clearly visible on the surfaces of the machined FPDs substructures, but no other flaws could be seen with the fluorescent penetrant method. After loading to fracture, the characteristic fracture features of arrest lines, compression curl, fracture mirror, fracture origin, hackle and twist hackle were detected. These findings indicated that the decisive fracture was initiated at the gingival embrasure of the pontic in association with a grinding groove. Thus, in three-unit heat-treated machined HIPed Y-TZP FPDs substructures, with the shape studied in this study, the gingival embrasure of the pontic seems to be a weak area providing a location for tensile stresses when they are occlusally loaded. In this area, fracture initiation may be located to a grinding groove.

  1. Gel combustion synthesis of yttria stabilized zirconia

    International Nuclear Information System (INIS)

    Vijay, Soja K.; Chandramouli, V.; Anthonysamy, S.

    2013-01-01

    Nano - crystalline 8 mol% yttria stabilized zirconia (YSZ) powders were synthesized by gel combustion technique employing both microwave heating as well as conventional heating method. Three different fuels - citric acid, urea and glycine were used for the synthesis with fuel to oxidant ratio as 1:1. The effect of fuel on the crystal structure, particle size, specific surface area, morphology and sintering density was studied. X-ray powder diffraction (XRD), BET gas adsorption technique, dynamic light scattering, transmission and scanning electron microscopy (TEM and SEM) and micro-Raman spectroscopy were used to characterize the powders. The results obtained for powders obtained using both methods - microwave assisted and hotplate - were compared. The specific surface area of powders in all cases are comparable except in the case of urea as fuel where microwave assisted synthesis yielded powders with lower surface area. The particle size distribution of all samples obtained using microwave method was unimodal, whereas the particle size distribution of samples prepared using hot plate method using urea fuel showed bimodal distribution. The compacts obtained using powders with citric acid and glycine as fuel showed more than 94% theoretical density, whereas the samples obtained using urea showed density below 90% of theoretical density. (author)

  2. Fracture toughness measurements on zirconia toughened ceramics

    International Nuclear Information System (INIS)

    El Sayed Ali, M.; Toft Soerensen, O.

    1986-12-01

    Three techniques for fracture toughness measurements on zirconia toughened ceramics were evaluated: the notched beam (NB) technique, the indentation fracture (IF) technique and the indentation strength in bending (ISB) technique. Using these techniques comparative measurements were performed on samples prepared by pressing (uniaxial) and sintering of four commercially available powder types. These were: Toya Soda (Japan) powders with the designations TZ3Y (2.86 mole% Y 2 O 3 ), TZ3YA (2.77 mole% Y 2 O 3 , 0.1 wt% Al 2 O 3 ) and TZ3Y20A (2.88 mole% Y 2 O 3 , 20 wt.% Al 2 O 3 ) and a powder supplied by Viking Chemicals (Denmark) designated as YP5Z-2.5 (2.5 mole% Y 2 O 3 ). The measurements showed that similar K Ic values were obtained with the IF- and ISB-techniques, which therefore are recommended for K Ic measurements. Too high values were, however, obtained with the NB-technique which therefore cannot be recommended. Finally, the measurements showed that a high temperature annealing is recommended prior to testing for the IF-technique. (author)

  3. Sintered stabilized zirconia microstructure and conductivity

    International Nuclear Information System (INIS)

    Bernard, Herve.

    1981-04-01

    The elaboration of a stabilized zirconia powder which sinters at 1300 0 C and the influence of the sintered polycristal microstructure on its ionic conductivity have been studied. Among three investigated powder preparation processes, coprecipitation in an ammoniacal solution was chosen. After sintering at 1300 0 C, the pellet density was higher than 93% of the theoretical density. It even approached up to 98% TD with addition of less than 0,5 mole % Al 2 O 3 to the initial powder. The overall electrolyte conductivity and the inter and intragranular contributions have been determined by complex impedance spectroscopy. ZrO 2 -Y 2 O 3 solid solution conductivity was scarcely improved by Y 2 O 3 exchange with Yb 2 O 3 or Gd 2 O 3 . This conductivity greatly increases with grain size, its improvement with decreasing porosity, which has been quantified, is less sensible. Moreover, two original properties were noticed: small amounts of Al 2 O 3 and quenching greatly enhanced the overall conductivity. At temperatures below 500 0 C, grain boundaries only insured a partial migration of conductive ions. A parallel type electrical equivalent circuit suited well with this blocking effect [fr

  4. Characterization of printed pigment-based inks on ink-jet media using cross-sectional electron microscopy

    International Nuclear Information System (INIS)

    Almeida, P. de; Pataki, T.; Peeters, D.; Roost, C. van

    2004-01-01

    This paper reports on the microscopic assessment of representative specimen cross-sections prepared by microtomy and ultramicrotomy with emphasis in structure-property information using optical, scanning and transmission electron microscopy, namely, the absolute optical density δ, the measured effective printing coverage C-tilde, the averaged pigment-based ink layer thickness t-bar, and the morphology at 100% nominal printing coverage. This work shows that for different test patches printed at the same nominal printing coverage a number of different printing schemes yield a pre-defined absolute optical density δ which basically depends on the measured effective printing coverage C-tilde and the type of pigment-based inks used (spectral absorptivity m≠∞) and therefore on the averaged pigment-based ink layer thickness t-bar. A method for estimating the spectral absorptivity m is presented which combines the absolute optical density δ of the test patch and the averaged pigment-based ink layer thickness t-bar as measured from cross-sectional electron microscopy

  5. Deformation bands in ceria-stabilized tetragonal zirconia/alumina. 2: Stress-induced aging at room temperature

    International Nuclear Information System (INIS)

    Sergo, V.; Clarke, D.R.

    1995-01-01

    A stress-induced aging phenomenon is observed to occur at room temperature in deformation bands introduced into a 8.5 mol% ceria-stabilized tetragonal zirconia/alumina (Ce-TZP/Al 2 O 3 ) composite by flexural loading. The aging occurs with time after unloading and in laboratory air. Over a period of 100 days, the concentration of monoclinic zirconia within a deformation band increases and, in addition, the wedge-shaped deformation band grows with time. Accompanying these two changes are an increase in the tensile stress in the remaining tetragonal zirconia within the deformation band and a consequential increase in the overall compressive stress within the band. The average value of the monoclinic concentration within the deformation band is found to increase parabolically with time, suggesting the mechanism responsible for the observed aging is diffusion limited. Away from the deformation bands, no aging is observed to occur, suggesting aging is stress dependent. Although a water-vapor-mediated mechanism cannot be ruled out, it is proposed that the observed aging is in fact due to a tensile stress assisted chemical reduction of Ce 4+ to Ce 3+ whose rate is controlled by the indiffusion of oxygen vacancies driven by the tensile stress gradient. It is further proposed that the deformation band grows with time the region ahead of the band is under tension a subject to an enhanced rate of reduction

  6. Synthesis, microstructure and mechanical properties of ceria stabilized tetragonal zirconia prepared by spray drying technique

    International Nuclear Information System (INIS)

    Sharma, S.C.; Gokhale, N.M.; Dayal, Rajiv; Lazl, Ramji

    2002-01-01

    Ceria stabilized zirconia powders with ceria concentration varying from 6 to 16 mol% were synthesized using spray drying technique. Powders were characterized for their particle size distribution and specific surface area. The dense sintered ceramics fabricated using these powders were characterized for their microstructure, crystallite size and phase composition. The flexural strength, fracture toughness and micro-hardness of sintered ceramics were measured. High fracture toughness and flexural strength were obtained for sintered bodies with 12 mol% of CeO 2 . Flexural strength and fracture toughness were dependent on CeO 2 concentration, crystallite size and phase composition of sintered bodies. Correlation of data has indicated that the transformable tetragonal phase is the key factor in controlling the fracture toughness and strength of ceramics. It has been demonstrated that the synthesis method is effective to prepare nanocrystalline tetragonal ceria stabilized zirconia powders with improved mechanical properties. Ce-ZrO 2 with 20 wt% alumina was also prepared with flexural strength, 1200 MPa and fracture toughness 9.2 MPa√m. (author)

  7. Suspension chemistry and electrophoretic deposition of zirconia electrolyte on conducting and non-conducting substrates

    International Nuclear Information System (INIS)

    Das, Debasish; Basu, Rajendra N.

    2013-01-01

    Graphical abstract: - Highlights: • Stable suspension of yttria stabilized zirconia (YSZ) obtained in isopropanol medium. • Suspension chemistry and process parameters for electrophoretic deposition optimized. • Deposited film quality changed with iodine and water (dispersants) concentration. • Dense YSZ film (∼5 μm) fabricated onto non-conducting porous NiO-YSZ anode substrate. - Abstract: Suspensions of 8 mol% yttria stabilized zirconia (YSZ) particulates in isopropanol medium are prepared using acetylacetone, iodine and water as dispersants. The effect of dispersants concentration on suspension stability, particle size distribution, electrical conductivity and pH of the suspensions are studied in detail to optimize the suspension chemistry. Electrophoretic deposition (EPD) has been conducted to produce thin and dense YSZ electrolyte films. Deposition kinetics have been studied in depth and good quality films on conducting substrate are obtained at an applied voltage of 15 V for 3 min. YSZ films are also fabricated on non-conducting NiO-YSZ anode substrate using a steel plate on the reverse side of the substrate. Upon co-firing at 1400 °C for 6 h a dense YSZ film of thickness ∼5 μm is obtained. Such a half cell (anode + electrolyte) can be used to fabricate a solid oxide fuel cell on applying a suitable cathode layer

  8. Tribological properties of toughened zirconia-based ceramics

    International Nuclear Information System (INIS)

    Stachowiak, G.W.; Stachowiak, G.B.

    1991-01-01

    The physical and mechanical properties of toughened zirconia ceramics are briefly characterized and described with a special emphasis on their tribological behaviour. The wear and friction properties of PSZ and TZP ceramics at room and elevated temperatures are described. The influence of the environment on the tribological characteristics of zirconia ceramics is discussed. Both lubricated and unlubricated conditions for ceramic/ceramic and metal/ceramic sliding contacts are analysed. One of the main, and as yet unresolved problems, lubrication of ceramic at elevated temperatures and/or space environment, is addressed and the possible solutions to the problem are suggested. The critical needs in the research and development area of improving the tribological properties of zirconia ceramics are defined and its future market potentials stated. 30 refs., 2 tabs., 4 figs

  9. Trial production and characterisation of fully calcia-stabilised zirconia

    International Nuclear Information System (INIS)

    George, A.M.; Karkhanavala, M.D.

    1980-01-01

    A process for manufacture of stabilized zirconia powder has been developed. The process is quite versatile since stabilization is achieved at relatively low temperatures (950deg - 1000deg C) and can be used for manufacture of either fully or partially calcia-stabilized zirconia. A 100 Kg trial batch of fully stabilized zirconia powder was produced accordingly at the Indian Rare Earths Ltd. plant and its characteristics were evaluated by XRD, microscopy, surface area and density measurements. The powder on firing at 1400deg C showed considerable volume shrinkage, as expected. On manually compacting with a phosphatic binder and firing for 8-10 hrs at 1300deg-1400deg C sintered shapes having bulk densities around 80-85% T.D. are easily obtained. Details of the measurements and the prospective industrial applications of the material are discussed. (auth.)

  10. Evaluation of technological properties of alumina refractory systems-zirconia and zirconia-silica-alumina; Avaliacao das propriedades tecnologicas de refratarios dos sistemas alumina-zirconia e alumina-zirconia-silica

    Energy Technology Data Exchange (ETDEWEB)

    Marinho, A.R.O.; Carvalho, T.U.S.; Fagury Neto, E.; Rabelo, A.A., E-mail: adriano@unifesspa.edu.br [Universidade Federal do Sul e Sudeste do Para (UFSSPA), Maraba, PA (Brazil)

    2014-07-01

    Alumina-zirconia refractories are noted for being products of excellent cost-effective, however, zirconia may limit its use due to decreasing resistance to thermal shock. This study aims to evaluate these refractories with the addition of microsilica, which can greatly improve their properties. Were used the following starting materials: calcined alumina, zirconia (stabilized and monoclinic) in amounts of 2%, 4% and 6% by weight, plus microsilica (5%w.). The powders were milled together with binder and lubricant for conformation bodies by uniaxial pressing. The samples were dried, calcined and sintered at 1400 °C/2h were characterized using the methods of Archimedes, and scanning electron microscopy (SEM), chemical analysis using energy dispersive X-ray (EDS), and mechanical flexural strength tests at room temperature. Formulations with the presence of microsilica showed satisfactory results and optimized properties. (author)

  11. Thermodynamic properties of some metal oxide-zirconia systems

    Science.gov (United States)

    Jacobson, Nathan S.

    1989-01-01

    Metal oxide-zirconia systems are a potential class of materials for use as structural materials at temperatures above 1900 K. These materials must have no destructive phase changes and low vapor pressures. Both alkaline earth oxide (MgO, CaO, SrO, and BaO)-zirconia and some rare earth oxide (Y2O3, Sc2O3, La2O3, CeO2, Sm2O3, Gd2O3, Yb2O3, Dy2O3, Ho2O3, and Er2O3)-zirconia system are examined. For each system, the phase diagram is discussed and the vapor pressure for each vapor species is calculated via a free energy minimization procedure. The available thermodynamic literature on each system is also surveyed. Some of the systems look promising for high temperature structural materials.

  12. The Metal-Zirconia Implant Fixed Hybrid Full-Arch Prosthesis: An Alternative Technique for Fabrication.

    Science.gov (United States)

    Stumpel, Lambert J; Haechler, Walter

    2018-03-01

    The metal-resin hybrid full-arch prosthesis has been a traditionally used type of restoration for full-arch implant fixed dentures. A newer development has centered around the use of monolithic zirconia or zirconia veneered with porcelain. Being a ceramic, zirconia has the potential for fracture. This article describes a technique that utilizes a metal substructure to support a chemically and mechanically resinbonded shell of zirconia. The workflow is discussed, ranging from in-office master cast fabrication to the CAD/ CAM production of the provisional and the definitive metal-zirconia prosthesis. The article also highlights the advantages and disadvantages of various materials used for hybrid prostheses.

  13. Electrophoretic Ink Display Prepared by Jelly Fig Pectin/Gelatin Microspheres

    Directory of Open Access Journals (Sweden)

    Wing-Ming Chou

    2015-05-01

    Full Text Available A brand new Bio-Electronic ink (Bio-E ink display device was prepared and characterized in this study. Semiconductor material, copper phthalocyanine (CuPc was modified by cationic surfactants, cetylpyridinium chloride (CPC, as the core material, and the shell of capsule was prepared by jelly fig pectin, gelatin and sodium dodecyl sulphate (SDS. Here, jelly fig pectin was provided as the shell material for the first time. Chemical structure of the modified CuPc was characterized by Fourier Transform Infrared Spectrometer (FTIR. The core-shell microcapsules were achieved by coacervation method in an oil/water (O/W emulsion system. The particle size and morphology of microcapsules were affected by the concentrations of SDS and pH values of the O/W emulsion system. A new microcapsule-based electrophoretic display device was presented. Its image display ability of the microcapsules electrophoretic device was presented as appropriated electric power was applied, and the response time was 0.06 sec under 0.1 V/mm of electric field. Moreover, we found that its image contrast ratio of display device was influenced by the particle sizes of the microcapsules.

  14. [Determination of photoinitiators in printing inks used in food contact materials].

    Science.gov (United States)

    Han, Wei; Yu, Yanjun; Li, Ningtao; Wang, Libing

    2011-05-01

    A new analytical method based on gas chromatography-mass spectrometry (GC-MS) techniques was developed for the determination of five photoinitiators (PIs), benzophenone (BP), 4-methylbenzophenone (MBP), ethyl-4-dimethylaminobenzoate (EDAB), 2-ethylhexyl-4-dimethylaminobenzoate (EHDAB) and 1-hydroxycyclohexyl phenyl ketone (Irgacure 184), in the printing inks used in food contact materials. The test solutions were extracted from selected food contact materials using Soxhlet extractor with ethyl acetate as the extraction solvent. By adding 50 and 200 microg/L of a standard mixture of photoinitiators into the extracts of the blank packaging materials, the recoveries obtained were in the range of 66.7%-89.4%. The repeatability of the method was assessed by determining the contents of the photoinitiators in five types of food contact materials, and the results were lower than 10%. The instrumental detection limits (IDLs) and method quantification limits (MQLs) were in the range of 2.9-6.0 microg/L and 0.0017-0.0036 mg/dm2, respectively. The method was applied in the analysis of about twenty real samples (yogurt carton, milk carton, fruit juice carton and plastic bags samples). The most significant pollutants were BP and MBP. The concentrations of Irgacure 184, EDAB and EHDAB found in three individual samples were 0.84 mg/dm2, 0.2 mg/dm2 and 1.2 mg/dm2, respectively. The work proposed a new method to analyze the migration level of initiators from the inks.

  15. High-speed imaging and evolution dynamics of laser induced deposition of conductive inks (Conference Presentation)

    Science.gov (United States)

    Makrygianni, Marina; Papazoglou, Symeon; Zacharatos, Filimonas; Chatzandroulis, Stavros; Zergioti, Ioanna

    2017-02-01

    During the last decade there is an ever-increasing interest for the study of laser processes dynamics and specifically of the Laser Induced Forward Transfer (LIFT) technique, since the evolution of the phenomena under investigation may provide real time metrology in terms of jet velocity, adjacent jet interaction and impact pressure. The study of such effects leads to a more thorough understanding of the deposition process, hence to an improved printing outcome and in these frames, this work presents a study on the dynamics of LIFT for conductive nanoparticles inks using high-speed imaging approaches. Moreover, in this study, we investigated the printing regimes and the printing quality during the transfer of copper (Cu) nanoink, which is a metallic nanoink usually employed in interconnect formation as well as the printing of silver nanowires, which provide transparency and may be used in applications where transparent electrodes are needed as in photovoltaics, batteries, etc. Furthermore, we demonstrate the fabrication of an all laser printed resistive chemical sensor device that combines Ag nanoparticles ink and graphene oxide, for the detection of humidity fabricated on a flexible polyimide substrate. The sensor device architecture was able to host multiple pairs of electrodes, where Ag nanoink or nanopaste were laser printed, to form the electrodes as well as the electrical interconnections between the operating device and the printed circuit board. Performance evaluation was conducted upon flow of different concentrations of humidity vapors to the sensor, and good response (500 ppm limit of detection) with reproducible operation was observed.

  16. Optical properties of pre-colored dental monolithic zirconia ceramics.

    Science.gov (United States)

    Kim, Hee-Kyung; Kim, Sung-Hun

    2016-12-01

    The purposes of this study were to evaluate the optical properties of recently marketed pre-colored monolithic zirconia ceramics and to compare with those of veneered zirconia and lithium disilicate glass ceramics. Various shades of pre-colored monolithic zirconia, veneered zirconia, and lithium disilicate glass ceramic specimens were tested (17.0×17.0×1.5mm, n=5). CIELab color coordinates were obtained against white, black, and grey backgrounds with a spectrophotometer. Color differences of the specimen pairs were calculated by using the CIEDE2000 (ΔE 00 ) formula. The translucency parameter (TP) was derived from ΔE 00 of the specimen against a white and a black background. X-ray diffraction was used to determine the crystalline phases of monolithic zirconia specimens. Data were analyzed with 1-way ANOVA, Scheffé post hoc, and Pearson correlation testing (α=0.05). For different shades of the same ceramic brand, there were significant differences in L * , a * , b * , and TP values in most ceramic brands. With the same nominal shade (A2), statistically significant differences were observed in L * , a * , b * , and TP values among different ceramic brands and systems (Pceramics of the corresponding nominal shades ranged beyond the acceptability threshold. Due to the high L * values and low a * and b * values, pre-colored monolithic zirconia ceramics can be used with additional staining to match neighboring restorations or natural teeth. Due to their high value and low chroma, unacceptable color mismatch with adjacent ceramic restorations might be expected. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Characterization of nanocrystalline zirconia powders by electron optical techniques

    International Nuclear Information System (INIS)

    Bursill, L.A.

    1989-01-01

    Electron optical techniques are described for the characterization of the size distribution of agglomerates, aggregates and primary micro- and nanocrystallites of as-processed zirconia powders. These techniques allow for direct identification of individual crystallites as tetragonal or monoclinic, by optical transform of high-resolution electron micrographs. The latter also permit surface morphology to be examined with atomic resolution. Applications to a range of pure and doped zirconia powders, of recent commercial interest, are presented, which enable the results of concurrent studies by sedimentation, surface specific area measurements, porosity and sinterability to be correctly interpreted. 18 figs

  18. Phase composition of yttrium-doped zirconia ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Hennig, Christoph; Scheinost, Andreas C. [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Molecular Structures; Weiss, Stephan [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes; Ikeda-Ohno, Atsushi [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Chemistry of the F-Elements; Gumeniuk, R. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Experimentelle Physik

    2017-06-01

    Ceramic material might be an alternative to borosilicate glass for the immobilization of nuclear waste. The crystallinity of ceramic material increases the corrosion resistance over several magnitudes in relation to amorphous glasses. The stability of such ceramics depend on several parameters, among them the crystal phase composition. A reliable quantitative phase analysis is necessary to correlate the macroscopic material properties with structure parameters. We performed a feasibility study based on yttrium-doped zirconia ceramics as analogue for trivalent actinides to ascertain that the nanosized crystal phases in zirconia ceramics can be reliably determined.

  19. Stabilization of metastable tetragonal zirconia nanocrystallites by surface modification

    DEFF Research Database (Denmark)

    Nielsen, Mette Skovgaard; Almdal, Kristoffer; Lelieveld, A. van

    2011-01-01

    Metastable tetragonal zirconia nanocrystallites were studied in humid air and in water at room temperature (RT). A stabilizing effect of different surfactants on the tetragonal phase was observed. Furthermore, the phase stability of silanized metastable tetragonal zirconia nanocrystallites was te...... exposure to humidity. Only silanes and phosphate esters of these were able to stabilize the tetragonal phase in water. Even as small amounts of silanes as 0.25 silane molecule per nm2 are able to stabilize the tetragonal phase in water at RT. Aminopropyl trimethoxy silane and γ...

  20. Kinetics of hydrothermally induced transformation of yttria partially stabilized zirconia

    International Nuclear Information System (INIS)

    Payyapilly, J.J.; Butt, D.P.

    2007-01-01

    Yttria-stabilized zirconia undergoes tetragonal to monoclinic phase transformation under hydrothermal conditions in the temperature range of 150-350 deg. C. Phase transformation accompanied by volume change in bulk yttria partially stabilized zirconia (YPSZ) leads to micro-cracking, loss of mechanical integrity and ultimately disintegration. The mechanical properties of the bulk YPSZ material deteriorate with the amount of the phase transformation and in some cases catastrophic failure are observed. The phase transformation is analyzed using macroscopic and microscopic techniques. X-ray diffraction data is used to quantify the phase transformation in bulk material. Kinetics of the phase transformation is studied at various temperatures

  1. Functionalization of sol-gel zirconia composites with europium complexes

    International Nuclear Information System (INIS)

    Danchova, Nina; Gutzov, Stoyan

    2014-01-01

    Different sol-gel strategies based on functionalization of ZrO 2 :Eu microparticles with 1,10-phenanthroline (phen) and incorporation of colloidal Eu(phen) 2 (NO 3 ) 3 into zirconia have been used to obtain hybrid sol-gel composites with controlled optical properties. The process leads to materials with quantum yields of about 48 % monitoring the 615 nm emission line at 350 nm excitation. Excitation/luminescence spectroscopy, diffuse reflectance spectroscopy and X-ray diffraction have been used to characterize the hybrid zirconia composites. (orig.)

  2. Surface modification of yttria stabilized zirconia by ion implantation

    International Nuclear Information System (INIS)

    Scholten, D.

    1987-01-01

    The results of investigations of surface modification by ion implantation in zirconia are described. As dopant material, iron was investigated thoroughly. The depth distribution of implanted ions depends on implantation parameters and the dopant-matrix system. The investigations of thermal stability of some implanted iron profiles by RBS and AES are described. Special interest lies in the thermal stability under working conditions of the zirconia material (400-1000 0 C). Radiation damage introduced in the implanted layer was investigated using transmission electron microscopy on polycrystalline material and channeling experiments on a single crystal implanted with iron. 179 refs.; 87 figs.; 20 tabs

  3. Mechanical behaviour of new zirconia-hydroxyapatite ceramic materials

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, J.A.; Morejon, L. [La Habana Univ. (Cuba). Centro de Biomateriales; Martinez, S. [Barcelona Univ. (Spain). Dept. Cristallografia, Mineralogia; Ginebra, M.P.; Carlsson, N.; Fernandez, E.; Planell, J.A. [Universidad Politecnica de Cataluna, Barcelona (Spain). CREB; Clavaguera-Mora, M.T.; Rodriguez-Viejo, J. [Universitat Autonoma de Barcelona (Spain). Dept. de Fisica

    2001-07-01

    In this work a new zirconia-hydroxyapatite ceramic material was obtained by uniaxial pressing and sintering in humid environment. The powder X-ray diffraction (XRD) patterns and infrared spectra (FT-IR) showed that the hydroxyapatite (HA) is the only calcium phosphate phase present. The fracture toughness for HA with 20 wt.% of magnesia partially stabilised zirconia (Mg-PSZ) was around 2.5 times higher than those obtained for HA pure, also the highest value of bending strength (160 MPa) was obtained for material reinforced with Mg-PSZ. For the MgPSZ-HA (20%) the fracture mechanism seems to be less transgranular. (orig.)

  4. FLOTATION DE-INKING OF 50% ONP/ 50% OMG RECOVERED PAPERS MIXTURES USING NONIONIC SURFACTANT, SOAP, AND SURFACTANT/SOAP BLENDS

    Directory of Open Access Journals (Sweden)

    Jeremy Allix

    2010-11-01

    Full Text Available A laboratory flotation column equipped with Venturi aerators and an adjustable froth removal system was used to study the effect of calcium soap and a mixture of calcium soap/alkyl phenol ethoxylate surfactant on ink and fibres transfer during flotation de-inking of a 50% old newprint (ONP / 50% old magazines (OMG recovered papers mixture. Mass transport phenomena determining the yield of the flotation process were interpreted using model equations describing particle removal in terms of flotation, entrainment, and drainage in the froth. A decrease in the ink and mineral fillers flotation rate constant, drainage through the froth, and in fibre entrainment was observed when increasing the surfactant concentration. These trends were consistent with the typical dispersing action of the studied nonionic surfactant. An opposite effect on ink and fillers was observed when using calcium soap alone, and the increase in the flotation rate constant and drainage through the froth were consistent with the collecting and defoaming action of the calcium soap. Moreover, fibre entrainment decreased when increasing the soap concentration. The study of the surfactant/soap mixture highlighted the absence of synergy between the calcium soap and the surfactant.

  5. Comparison of bond strengths of ceramic brackets bonded to zirconia surfaces using different zirconia primers and a universal adhesive.

    Science.gov (United States)

    Lee, Ji-Yeon; Ahn, Jaechan; An, Sang In; Park, Jeong-Won

    2018-02-01

    The aim of this study is to compare the shear bond strengths of ceramic brackets bonded to zirconia surfaces using different zirconia primers and universal adhesive. Fifty zirconia blocks (15 × 15 × 10 mm, Zpex, Tosoh Corporation) were polished with 1,000 grit sand paper and air-abraded with 50 µm Al 2 O 3 for 10 seconds (40 psi). They were divided into 5 groups: control (CO), Metal/Zirconia primer (MZ, Ivoclar Vivadent), Z-PRIME Plus (ZP, Bisco), Zirconia Liner (ZL, Sun Medical), and Scotchbond Universal adhesive (SU, 3M ESPE). Transbond XT Primer (used for CO, MZ, ZP, and ZL) and Transbond XT Paste was used for bracket bonding (Gemini clear ceramic brackets, 3M Unitek). After 24 hours at 37°C storage, specimens underwent 2,000 thermocycles, and then, shear bond strengths were measured (1 mm/min). An adhesive remnant index (ARI) score was calculated. The data were analyzed using one-way analysis of variance and the Bonferroni test ( p = 0.05). Surface treatment with primers resulted in increased shear bond strength. The SU group showed the highest shear bond strength followed by the ZP, ZL, MZ, and CO groups, in that order. The median ARI scores were as follows: CO = 0, MZ = 0, ZP = 0, ZL = 0, and SU = 3 ( p < 0.05). Within this experiment, zirconia primer can increase the shear bond strength of bracket bonding. The highest shear bond strength is observed in SU group, even when no primer is used.

  6. Black Ink and Red Ink (BIRI) Testing: A Testing Method to Evaluate Both Recall and Recognition Learning in Accelerated Adult-Learning Courses

    Science.gov (United States)

    Rodgers, Joseph Lee; Rodgers, Jacci L.

    2011-01-01

    We propose, develop, and evaluate the black ink-red ink (BIRI) method of testing. This approach uses two different methods within the same test administration setting, one that matches recognition learning and the other that matches recall learning. Students purposively define their own tradeoff between the two approaches. Evaluation of the method…

  7. The effect of sampling methods on the apparent constituents of ink from the squid Sepioteuthis australis.

    Science.gov (United States)

    Madaras, F; Gerber, J P; Peddie, F; Kokkinn, M J

    2010-11-01

    Results of experiments conducted on ink recovered from the squid Sepioteuthis australis indicate that there is no epinephrine or protein naturally present in the ink as it would be ejected in vivo. Protein content was effectively zero when ink was syringed from the duct end of the ink sac of freshly killed animals. By contrast, there were proteins in samples collected from dead specimens where ink was collected by a stripping method. From these samples, a single large molecular weight protein was identified as having tyrosinase activity. Digestion of syringed ink did not yield signs of melanin-bound proteins. Analysis of supernatants after centrifugation of squid ink consistently revealed the presence of DOPA, dopamine, and taurine, whereas epinephrine and nor-epinephrine were recorded from what was believed to be contaminated ink. Histological investigations of the ink sac revealed a compartmentalised glandular structure distal to the duct end. Closer observation of the glandular tissue showed that compartments increased in size as they matured and moved further into the lumen. It was concluded that the presence of epinephrine and tyrosinase (or a related protein) in the ink of S. australis could be attributed to rupturing of basal glandular compartments or contamination from other sources during the extraction process.

  8. Effect of Hyperbranched Polymers on Curing Behavior of UV Curable Inks in Inkjet Printing

    Directory of Open Access Journals (Sweden)

    Samane Jafarifard

    2016-07-01

    Full Text Available A high quality and high resolution printing can be rapidly created by inkjet printing technology. Inkjet printing is one of the most economic printing methods and ink waste in this technique is very low. Inkjet process provides printing on any type of substrates. The UV curable inks are special types of printing inks that have been widely used in the last decades. The use of UV curable inks is more attractive in inkjet printing technology in comparison to other methods of printing. The most important advantage of UV curable inks in this method is that they are VOC-free and compatible and have good adhesion on many types of substrates. In this research, the effect of hyperbranched polymers on the curing behavior of UV curable inks was investigated. Two types of hyperbranched polymers with hydroxyl and fatty acid chain terminal groups were used in ink formulations. The effect of hyperbranched polymers on the curing behavior of UV curable ink was investigated by real-time FTIR analysis. The results showed that the hyperbranched polymers could improve curing process by increasing the conversion rate of the third curing stage. All ink formulations containing hyperbranched polymers showed higher conversion than a neat sample. The highest conversion was 77 % for the blend containing a hyperbranched polymer with hydroxyl end groups while the neat sample showed a final conversion of 55%. UV curable inks in inkjet process containing hyperbranched polymers with hydroxyl end groups showed a higher final conversion than neat sample.

  9. MR scanning, tattoo inks, and risk of thermal burn

    DEFF Research Database (Denmark)

    Alsing, K. K.; Johannesen, H. H.; Hvass Hansen, R.

    2017-01-01

    : Magnetic resonance imaging effects on 3 commonly used commercial ink stock products marketed for cosmetic tattooing was studied. A main study tested 22 formulations based on 11 pigment raw materials, for example, one line of 11 called pastes and another called dispersions. Samples were spread in petri...... dishes and tested with a 0.97 T neodymium solid magnet to observe visual magnetic behavior. Before MRI, the surface temperature of the ink was measured using an infrared probe. Samples were placed in a clinical 3T scanner. Two scans were performed, that is, one in the isocenter and one 30 cm away from...... the center. After scanning, the surface temperature was measured again. Chemical analysis of samples was performed by mass spectroscopy. Results: Mean temperature increase measured in the isocenter ranged between 0.14 and 0.26°C (P

  10. Atmospheric pressure DBD gun and its application in ink printability

    International Nuclear Information System (INIS)

    Chen Qiang; Zhang Yuefei; Han Erli; Ge Yuanjing

    2005-01-01

    In this paper, a plasma source discharging at atmospheric pressure and its characterization diagnosed by a Langmuir probe and a digital camera are presented. As an application the dielectric barrier discharge (DBD) gun modifying an ultraviolet cured resin surface for ink printability is reported. The results from the digital camera indicate the uniformity and homogeneity of the plasma generated from the gun in the downstream but depending on the input power, diameter of electrodes, gas flow rates and the distance between the substrates and the nozzle. The contact angle measurement proves the efficiency of gun during the surface modification. The ink printability following DBD gun processing described here was significantly improved. The performed surface analysis using Fourier transform infrared indicates that the polarity of surface grafted in plasma is responsible for the film printability

  11. Effect of hydrophobic microstructured surfaces on conductive ink printing

    International Nuclear Information System (INIS)

    Kim, Seunghwan; Kang, Hyun Wook; Lee, Kyung Heon; Sung, Hyung Jin

    2011-01-01

    Conductive ink was printed on various microstructured substrates to measure the printing quality. Poly-dimethylsiloxane (PDMS) substrates were used to test the printability of the hydrophobic surface material. Microstructured arrays of 10 µm regular PDMS cubes were prepared using the MEMS fabrication technique. The gap distance between the cubes was varied from 10 to 40 µm. The printing wettability of the microstructured surfaces was determined by measuring the contact angle of a droplet of silver conductive ink. Screen-printing methods were used in the conductive line printing experiment. Test line patterns with finely varying widths (30–250 µm) were printed repeatedly, and the conductivity of the printed lines was measured. The printability, which was defined as the ratio of the successfully printed patterns to the total number of printed patterns, was analyzed as a function of the linewidth and the gap distance of the microstructured surfaces

  12. Direct ink write fabrication of transparent ceramic gain media

    Science.gov (United States)

    Jones, Ivy Krystal; Seeley, Zachary M.; Cherepy, Nerine J.; Duoss, Eric B.; Payne, Stephen A.

    2018-01-01

    Solid-state laser gain media based on the garnet structure with two spatially distinct but optically contiguous regions have been fabricated. Transparent gain media comprised of a central core of Y2.97Nd0.03Al5.00O12.00 (Nd:YAG) and an undoped cladding region of Y3Al5O12 (YAG) were fabricated by direct ink write and transparent ceramic processing. Direct ink write (DIW) was employed to form the green body, offering a general route to preparing functionally structured solid-state laser gain media. Fully-dense transparent optical ceramics in a "top hat" geometry with YAG/Nd:YAG have been fabricated by DIW methods with optical scatter at 1064 nm of <3%/cm.

  13. Powder ink coatings in nuclear medicine and nuclear technology

    International Nuclear Information System (INIS)

    Kunze, S.; Schlautek, H.

    1996-01-01

    Powder ink coatings are being used more and more frequently to protect the surfaces of movable objects of metal, such as machines, equipment, furniture, shelves, because this solvent-free coating technique, which produces almost no residues, helps to keep the environment clean. The white and grey baking coatings so far tested for decontaminability are presented in the article. Powder ink coatings of different shades and with different binders were tested for their ability to meet future standards. All systems under examination demonstrated excellent decontaminability before and after gamma exposure to 0.3 MGy. The same performance was obtained also after exposure to 3 MGy (ten times the level required for coatings in nuclear installations according to DIN 55991 Part 1), with the exception of one polyester metallic coating. After having been exposed to chemicals and decontamination solutions, all specimens showed only permissible discoloration. (orig.) [de

  14. Inkjet printing technology and conductive inks synthesis for microfabrication techniques

    International Nuclear Information System (INIS)

    Dang, Mau Chien; Dung Dang, Thi My; Fribourg-Blanc, Eric

    2013-01-01

    Inkjet printing is an advanced technique which reliably reproduces text, images and photos on paper and some other substrates by desktop printers and is now used in the field of materials deposition. This interest in maskless materials deposition is coupled with the development of microfabrication techniques for the realization of circuits or patterns on flexible substrates for which printing techniques are of primary interest. This paper is a review of some results obtained in inkjet printing technology to develop microfabrication techniques at Laboratory for Nanotechnology (LNT). Ink development, in particular conductive ink, study of printed patterns, as well as application of these to the realization of radio-frequency identification (RFID) tags on flexible substrates, are presented. (paper)

  15. Zirconia-mullite obtained from co-precipitated zirconia-mullite composite powders by SPS

    Energy Technology Data Exchange (ETDEWEB)

    Li, H.Z.; Li, Z.J.; Luo, X.D. [Univ. of Science and Technology Liaoning, Anshan (China). School of High Temperature Materials and Magnesium Resource Engineering; Gui, J.Y.; Xie, Z.P. [Tsinghua Univ., Beijing (China). School of Materials Science and Engineering

    2016-07-01

    The co-precipitation method is used to fabricate precursor powder. This powder is densified by means of the spark plasma sintering (SPS) technique at 1500 C with a holding time of 7 min to prepare zirconia-mullite samples. Their density measures up to 97 % of the theoretical density, and the sintered mullite compacts exhibit better strength properties (289 ± 12 MPa) and H{sub v} (9.99 GPa). The mode of fracture is changed with the addition of ZrO{sub 2} and extensive fine cleavages are observed on the grain surface. These cleavages join together to form steps, which can absorb more energy. The flexural strength of the samples is almost double that of pure mullite, which is related to the formation of cleavages.

  16. Esterification of fatty acids using sulfated zirconia and composites activated carbon/sulfated zirconia catalysts

    International Nuclear Information System (INIS)

    Brum, Sarah S.; Santos, Valeria C. dos; Destro, Priscila; Guerreiro, Mario Cesar

    2011-01-01

    In this work sulfated zirconia (SZr) and activated carbon/SZr composites produced by impregnation method with or without heating treatment step (CABC/SZr-I and CABC/SZr-I SC) and by the method of synthesis of SZr on the carbon (CABC/SZr-S) was used as catalysts in the esterification reactions of fatty acids. The SZr presented very active, conversions higher than 90% were obtained after 2 h of reaction. The activity of the composite CABC/SZr-I20%SC was up to 92%, however, this was directly related to time and temperature reactions. CABC/SZr-I and CABC/SZr-S were less active in esterification reactions, what could be attributed to its low acidity. (author)

  17. Aqueous degradation kinetics of pharmaceutical drug diclofenac by photo catalysis using nano structured titania–zirconia composite catalyst

    International Nuclear Information System (INIS)

    Das, L.; Barodia, S. K.; Sengupta, S.; Basu, J. K.

    2015-01-01

    Diclofenac is an anti-inflammatory pharmaceutical drug and its presence in a trace amount in waste water makes severe environmental pollution. The degradation of diclofenac was investigated by a photo catalytic process in presence of ultra violet irradiation at room temperature using titania and titania-zirconia nano composite catalysts in a batch reactor. The composite catalyst was prepared by sol-gel method and characterized by X-ray diffraction, transmission electron microscopy as well as BET surface area analyzer. The effect of various process parameters such as catalyst loading, initial concentration of diclofenac and p H of the experimental solution was observed on the degradation of diclofenac. The titania-zirconia nano composites exhibited reasonably higher photo catalytic activity than that of anatase form of titania without zirconia. The maximum removal of diclofenac of about 92.41% was achieved using Zr/Ti mass ratio of 11.8 wt% composite catalyst. A rate equation was proposed for the degradation of diclofenac using the composite catalyst. The values of rate constant (kc) and adsorption equilibrium constant (K1) were found to vary with the catalyst content in the reaction mixture.

  18. Inkjet printing of silver citrate conductive ink on PET substrate

    Energy Technology Data Exchange (ETDEWEB)

    Nie Xiaolei [Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Wang Hong, E-mail: hongwang@tju.edu.cn [Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Zou Jing [Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer A direct synthesis method of silver conductive film on PET substrate was presented. Black-Right-Pointing-Pointer A stable particle-free conductive ink was prepared. Black-Right-Pointing-Pointer Formation of silver-amine complex reduced the thermal decomposition temperature. Black-Right-Pointing-Pointer Conductive patterns for flexible electronics were fabricated by inkjet printing. Black-Right-Pointing-Pointer Silver film on PET substrate possessed highest adhesion rating even without polymer. - Abstract: Direct synthesis of silver conductive film on PET substrate by inkjet printing silver citrate conductive ink was presented in this paper. This kind of conductive ink contained silver citrate as silver precursor, 1,2-diaminopropane as complex agent dissolving the silver salt and methanol and isopropanol as a media adjusting the viscosity and surface tension. The formation of silver-amine complex reduced the decomposition temperature from 180 Degree-Sign C to 135 Degree-Sign C, thus the ink could be cured at relatively low temperature. The film reached the lowest resistivity of 17 {mu}{Omega} cm after cured at 150 Degree-Sign C for 50 min, 3.1 {mu}{Omega} cm at 230 Degree-Sign C and possessed high reflection and excellent adhesive property. Electrical conductivity, surface morphology and composition were investigated by four-point probe method, scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS). It is demonstrated how the cured condition affects the silver film. Moreover, radio-frequency identification (RFID) antenna was fabricated by inkjet printing, which opens up routes for the flexible electronics fabrication.

  19. Mod silver metallization: Screen printing and ink-jet printing

    Science.gov (United States)

    Vest, R. W.; Vest, G. M.

    1985-01-01

    Basic material efforts have proven to be very successful. Adherent and conductive films were achieved. A silver neodecanoate/bismuth 2-ethylhexanoate mixture has given the best results in both single and double layer applications. Another effort is continuing to examine the feasibility of applying metallo-organic deposition films by use of an ink jet printer. Direct line writing would result in a saving of process time and materials. So far, some well defined lines have been printed.

  20. Inkjet printing of silver citrate conductive ink on PET substrate

    International Nuclear Information System (INIS)

    Nie Xiaolei; Wang Hong; Zou Jing

    2012-01-01

    Highlights: ► A direct synthesis method of silver conductive film on PET substrate was presented. ► A stable particle-free conductive ink was prepared. ► Formation of silver-amine complex reduced the thermal decomposition temperature. ► Conductive patterns for flexible electronics were fabricated by inkjet printing. ► Silver film on PET substrate possessed highest adhesion rating even without polymer. - Abstract: Direct synthesis of silver conductive film on PET substrate by inkjet printing silver citrate conductive ink was presented in this paper. This kind of conductive ink contained silver citrate as silver precursor, 1,2-diaminopropane as complex agent dissolving the silver salt and methanol and isopropanol as a media adjusting the viscosity and surface tension. The formation of silver-amine complex reduced the decomposition temperature from 180 °C to 135 °C, thus the ink could be cured at relatively low temperature. The film reached the lowest resistivity of 17 μΩ cm after cured at 150 °C for 50 min, 3.1 μΩ cm at 230 °C and possessed high reflection and excellent adhesive property. Electrical conductivity, surface morphology and composition were investigated by four-point probe method, scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS). It is demonstrated how the cured condition affects the silver film. Moreover, radio-frequency identification (RFID) antenna was fabricated by inkjet printing, which opens up routes for the flexible electronics fabrication.

  1. Coagulation and Adsorption Treatment of Printing Ink Wastewater

    OpenAIRE

    Klančnik, Maja

    2014-01-01

    The intention of the study was to improve the efficiency of total organic carbon (TOC) and colour removal from the wastewater samples polluted with flexographic printing ink following coagulation treatments with further adsorption onto activated carbons and ground orange peel. The treatment efficiencies were compared to those of further flocculation treatments and of coagulation and adsorption processes individually. Coagulation was a relatively effective single-treatment method, removing 99...

  2. Advanced Methods for Direct Ink Write Additive Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Compel, W. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Lewicki, J. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2018-01-24

    Lawrence Livermore National Laboratory is one of the world’s premier labs for research and development of additive manufacturing processes. Out of these many processes, direct ink write (DIW) is arguably one of the most relevant for the manufacture of architected polymeric materials, components and hardware. However, a bottleneck in this pipeline that has largely been ignored to date is the lack of advanced software implementation with respect to toolpath execution. There remains to be a convenient, automated method to design and produce complex parts that is user-friendly and enabling for the realization of next generation designs and structures. For a material to be suitable as a DIW ink it must possess the appropriate rheological properties for this process. Most importantly, the material must exhibit shear-thinning in order to extrude through a print head and have a rapid recovery of its static shear modulus. This makes it possible for the extrudate to be self-supporting upon exiting the print head. While this and other prerequisites narrow the scope of ‘offthe- shelf’ printable materials directly amenable to DIW, the process still tolerates a wide range of potential feedstock materials. These include metallic alloys, inorganic solvent borne dispersions, polymeric melts, filler stabilized monomer compositions, pre-elastomeric feedstocks and thermoset resins each of which requires custom print conditions tailored to the individual ink. As such, an ink perfectly suited for DIW may be prematurely determined to be undesirable for the process if printed under the wrong conditions. Defining appropriate print conditions such as extrusion rate, layer height, and maximum bridge length is a vital first step in validating an ink’s DIW capability.

  3. 3D Printing by Multiphase Silicone/Water Capillary Inks.

    Science.gov (United States)

    Roh, Sangchul; Parekh, Dishit P; Bharti, Bhuvnesh; Stoyanov, Simeon D; Velev, Orlin D

    2017-08-01

    3D printing of polymers is accomplished easily with thermoplastics as the extruded hot melt solidifies rapidly during the printing process. Printing with liquid polymer precursors is more challenging due to their longer curing times. One curable liquid polymer of specific interest is polydimethylsiloxane (PDMS). This study demonstrates a new efficient technique for 3D printing with PDMS by using a capillary suspension ink containing PDMS in the form of both precured microbeads and uncured liquid precursor, dispersed in water as continuous medium. The PDMS microbeads are held together in thixotropic granular paste by capillary attraction induced by the liquid precursor. These capillary suspensions possess high storage moduli and yield stresses that are needed for direct ink writing. They could be 3D printed and cured both in air and under water. The resulting PDMS structures are remarkably elastic, flexible, and extensible. As the ink is made of porous, biocompatible silicone that can be printed directly inside aqueous medium, it can be used in 3D printed biomedical products, or in applications such as direct printing of bioscaffolds on live tissue. This study demonstrates a number of examples using the high softness, elasticity, and resilience of these 3D printed structures. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Inkjet printing of silver citrate conductive ink on PET substrate

    Science.gov (United States)

    Nie, Xiaolei; Wang, Hong; Zou, Jing

    2012-11-01

    Direct synthesis of silver conductive film on PET substrate by inkjet printing silver citrate conductive ink was presented in this paper. This kind of conductive ink contained silver citrate as silver precursor, 1,2-diaminopropane as complex agent dissolving the silver salt and methanol and isopropanol as a media adjusting the viscosity and surface tension. The formation of silver-amine complex reduced the decomposition temperature from 180 °C to 135 °C, thus the ink could be cured at relatively low temperature. The film reached the lowest resistivity of 17 μΩ cm after cured at 150 °C for 50 min, 3.1 μΩ cm at 230 °C and possessed high reflection and excellent adhesive property. Electrical conductivity, surface morphology and composition were investigated by four-point probe method, scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS). It is demonstrated how the cured condition affects the silver film. Moreover, radio-frequency identification (RFID) antenna was fabricated by inkjet printing, which opens up routes for the flexible electronics fabrication.

  5. Coagulation and Adsorption Treatment of Printing Ink Wastewater

    Directory of Open Access Journals (Sweden)

    Maja Klančnik

    2015-03-01

    Full Text Available The intention of the study was to improve the efficiency of total organic carbon (TOC and colour removal from the wastewater samples polluted with flexographic printing ink following coagulation treatments with further adsorption onto activated carbons and ground orange peel. The treatment efficiencies were compared to those of further flocculation treatments and of coagulation and adsorption processes individually. Coagulation was a relatively effective single-treatment method, removing 99.7% of the colour and 86.9% of the organic substances (TOC from the printing ink wastewater samples. Further flocculation did not further eliminate organic pollutants, whereas subsequent adsorption with 7 g/l of granular activated carbon further reduced organic substances by 35.1%, and adsorption with 7 g/l of powdered activated carbon further reduced organic substances by 59.3%. Orange peel was an inappropriate adsorbent for wastewater samples with low amounts of pollution, such as water that had been treated by coagulation. However, in highly polluted printing ink wastewater samples, the adsorption treatment with ground orange peel achieved efficiencies comparable to those of the granular activated carbon treatments.

  6. Transmutation of americium and curium incorporated in zirconia-based host materials

    Energy Technology Data Exchange (ETDEWEB)

    Raison, P.E. [CEA Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. d' Etudes des Combustibles; Haire, R.G. [Oak Ridge National Lab., TN (United States)

    2001-07-01

    Presented are studies involving the incorporation of americium and curium in zirconia-based materials. First explored was the pseudo ternary system AmO{sub 2}-ZrO{sub 2}-Y{sub 2}O{sub 3}. It was determined that selected Y-CSZ materials can incorporate significant quantities of americium oxide and remain cubic single-phase. The cell parameters of these fluorite-type products were established to be linear with the AmO{sub 2} content. The Cm{sub 2}O{sub 3}-ZrO{sub 2} system was also investigated. It was found that at 25 mol% of CmO{sub 1.5}, the Cm(III) stabilized zirconia in its cubic form (a = 5.21 {+-}0.01 Angstrom). At higher and lower concentrations, diphasic materials were encountered. At 50 mol% of CmO{sub 1.5}, a pyrochlore oxide - Cm{sub 2}Zr{sub 2}O{sub 7} - is formed (a = 10.63 {+-}0.02 Angstrom). (author)

  7. Dispersion and consolidation of WO{sub x}-doped zirconia from zirconium tungstate and triethanolamine in aqueous medium; Dispersao e consolidacao de zirconia dopada com WO{sub x} a partir do tungstato de zirconio e trietanolamina em meio aquoso

    Energy Technology Data Exchange (ETDEWEB)

    Antunes, M.; Zorzi, J.E.; Perottoni, C.A., E-mail: jezorzi@ucs.br [Universidade de Caxias do Sul (UCS), RS (Brazil); Machado, G. [Centro de Tecnologias Estrategicas do Nordeste, Recife, PE (Brazil)

    2017-01-15

    In recent studies, it was possible to produce hydrous zirconia nanoparticles with crystallite sizes as small as 2 nm from ZrW{sub 2} O{sub 8} powder with initial particle size of 1.7 μm in an aqueous medium. The zirconia nanoparticles formed transparent polycrystalline aggregates. However, the controlled production of transparent zirconia solids by centrifugation of stable suspensions, deagglomerated in the moment of the synthesis, has not been explored yet. In this context, this study aimed to evaluate the dispersion and consolidation of hydrous zirconia nanoparticles produced from ZrW{sub 2} O{sub 8} , in aqueous medium and using triethanolamine (TEOA) as surfactant, and to understand the effect of experimental conditions on the tungsten content in the consolidated solids. The synthesis and dispersion were carried out in aqueous medium at 80 °C with the use of NaOH and TEOA; the colloidal solutions were dialysed, their pH values were adjusted to 6, and then ultracentrifuged at 28000 rpm for 24 h. It has been found that the use of TEOA in the synthesis allowed obtaining stable sols of zirconia nanoparticles which, after centrifugation, originated transparent and yellowish solids that were characterized using various techniques (scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, and simultaneous thermal analysis). Although TEOA assists in the dispersion of nanoparticles, it interfered in the synthesis mechanism, leading to the production of zirconia doped with WO{sub x} , with tungsten concentrations that varied depending on the experimental conditions employed. (author)

  8. Characteristics of porous zirconia coated with hydroxyapatite as ...

    Indian Academy of Sciences (India)

    TECS

    Zirconia; porosity; hydroxyapatite; coating; compressive strength. 1. Introduction. A lot of .... typically from 300–500 μm, estimated from the SEM images. Thus, the .... Kim H W, Georgiou F, Knowles J C, Koh Y H and Kim H E. 2004 Biomaterials ...

  9. TOF-SIMS studies of yttria-stabilised zirconia

    DEFF Research Database (Denmark)

    Hansen, Karin Vels; Norrman, Kion; Mogensen, Mogens Bjerg

    2006-01-01

    The surface of an as-polished and an as-sintered yttria-stabilised zirconia pellet was analysed with XPS and TOF-SIMS (depth profiling and imaging) in order to study the distribution of impurities. The polished sample was slightly contaminated with Na, K, Mg and Ca. The sintered sample showed...

  10. Thermodynamic assessment of the zirconia-urania system

    International Nuclear Information System (INIS)

    Yashima, Masatomo; Koura, Toshiaki; Du, Y.; Yoshimura, Masahiro

    1996-01-01

    An optimal thermodynamic data set for the zirconia-urania system is devaluated by the CALPHAD (CALculation of PHAse Diagrams) method. A regular solution model is applied to all phases of the cubic, tetragonal, and monoclinic solid solutions and the liquid. Comparisons between calculated and measured phase diagrams show that most of the experimental information is satisfactorily accounted for by thermodynamic calculations

  11. Surface roughness and morphologic changes of zirconia: Effect of ...

    African Journals Online (AJOL)

    4-6 W/20 Hz presented significantly effect in surface roughness changes of zirconia than other surface treatments. Key words:Erbium, chromium: Yttrium, scandium, gallium, garnet laser, scanning electron .... ZrO2, (f) After sintering ZrO2 in letter “e”, (g) 2 W laser irridiation pre-sintered ZrO2, (h) After ..... Acta Odontol Scand.

  12. Synthesis of Ca,Y-zirconia/hydroxyapatite nanoparticles and composites

    Czech Academy of Sciences Publication Activity Database

    Částková, K.; Hadraba, Hynek; Matoušek, A.; Roupcová, P.; Chlup, Zdeněk; Novotná, L.; Cihlář, J.

    2016-01-01

    Roč. 36, č. 12 (2016), s. 2903-2912 ISSN 0955-2219 R&D Projects: GA ČR GA14-11234S; GA MŠk(CZ) LQ1601 Institutional support: RVO:68081723 Keywords : Zirconia * Hydroxyapatite * Composite * Bioactivity * Mechanical properties Subject RIV: JH - Ceramic s, Fire-Resistant Materials and Glass Impact factor: 3.411, year: 2016

  13. Synthesis and chromatographic characterization of dextran-coated zirconia high-performance liquid chromatographic stationary phases.

    Science.gov (United States)

    Dunlap, C J; Carr, P W

    1996-10-11

    Porous zirconia particles made by the oil emulsion (OE) method and the polymerization-induced colloid aggregation (PICA) method have been coated with a small, carboxymethylated (approximately 5%) dextran polymer and crosslinked in place. The parameters of the coating process (dextran concentration, adsorption time and crosslinker concentration) have all been examined and an optimum value for each determined. The coated and uncoated materials were characterized by nitrogen sorptometry and size-exclusion chromatography (SEC) using solutes (polystyrenes and dextrans) of well-defined molecular masses. Nitrogen sorptometry results show that the PICA material has a much lower pore volume and smaller pore diameter than do the OE materials. Despite this, the elution volumes of the SEC probes change very little upon polymer coating the PICA material while the OE material shows a very large change upon coating.

  14. Novel materials for electronic device fabrication using ink-jet printing technology

    International Nuclear Information System (INIS)

    Kumashiro, Yasushi; Nakako, Hideo; Inada, Maki; Yamamoto, Kazunori; Izumi, Akira; Ishihara, Masamichi

    2009-01-01

    Novel materials and a metallization technique for the printed electronics were studied. Insulator inks and conductive inks were investigated. For the conductive ink, the nano-sized copper particles were used as metallic sources. These particles were prepared from a copper complex by a laser irradiation process in the liquid phase. Nano-sized copper particles were consisted of a thin copper oxide layer and a metal copper core wrapped by the layer. The conductive ink showed good ink-jettability. In order to metallize the printed trace of the conductive ink on a substrate, the atomic hydrogen treatment was carried out. Atomic hydrogen was generated on a heated tungsten wire and carried on the substrate. The temperature of the substrate was up to 60 deg. C during the treatment. After the treatment, the conductivity of a copper trace was 3 μΩ cm. It was considered that printed wiring boards can be easily fabricated by employing the above materials.

  15. In vitro assessment of cutting efficiency and durability of zirconia removal diamond rotary instruments.

    Science.gov (United States)

    Kim, Joon-Soo; Bae, Ji-Hyeon; Yun, Mi-Jung; Huh, Jung-Bo

    2017-06-01

    Recently, zirconia removal diamond rotary instruments have become commercially available for efficient cutting of zirconia. However, research of cutting efficiency and the cutting characteristics of zirconia removal diamond rotary instruments is limited. The purpose of this in vitro study was to assess and compare the cutting efficiency, durability, and diamond rotary instrument wear pattern of zirconia diamond removal rotary instruments with those of conventional diamond rotary instruments. In addition, the surface characteristics of the cut zirconia were assessed. Block specimens of 3 mol% yttrium cation-doped tetragonal zirconia polycrystal were machined 10 times for 1 minute each using a high-speed handpiece with 6 types of diamond rotary instrument from 2 manufacturers at a constant force of 2 N (n=5). An electronic scale was used to measure the lost weight after each cut in order to evaluate the cutting efficiency. Field emission scanning electron microscopy was used to evaluate diamond rotary instrument wear patterns and machined zirconia block surface characteristics. Data were statistically analyzed using the Kruskal-Wallis test, followed by the Mann-Whitney U test (α=.05). Zirconia removal fine grit diamond rotary instruments showed cutting efficiency that was reduced compared with conventional fine grit diamond rotary instruments. Diamond grit fracture was the most dominant diamond rotary instrument wear pattern in all groups. All machined zirconia surfaces were primarily subjected to plastic deformation, which is evidence of ductile cutting. Zirconia blocks machined with zirconia removal fine grit diamond rotary instruments showed the least incidence of surface flaws. Although zirconia removal diamond rotary instruments did not show improved cutting efficiency compared with conventional diamond rotary instruments, the machined zirconia surface showed smoother furrows of plastic deformation and fewer surface flaws. Copyright © 2016 Editorial Council

  16. Surface roughness of zirconia for full-contour crowns after clinically simulated grinding and polishing.

    Science.gov (United States)

    Hmaidouch, Rim; Müller, Wolf-Dieter; Lauer, Hans-Christoph; Weigl, Paul

    2014-12-01

    The aim of this study was to evaluate the effect of controlled intraoral grinding and polishing on the roughness of full-contour zirconia compared to classical veneered zirconia. Thirty bar-shaped zirconia specimens were fabricated and divided into two groups (n=15). Fifteen specimens (group 1) were glazed and 15 specimens (group 2) were veneered with feldspathic ceramic and then glazed. Prior to grinding, maximum roughness depth (Rmax) values were measured using a profilometer, 5 times per specimen. Simulated clinical grinding and polishing were performed on the specimens under water coolant for 15 s and 2 N pressure. For grinding, NTI diamonds burs with grain sizes of 20 µm, 10 µm, and 7.5 µm were used sequentially. The ground surfaces were polished using NTI kits with coarse, medium and fine polishers. After each step, Rmax values were determined. Differences between groups were examined using one-way analysis of variance (ANOVA). The roughness of group 1 was significantly lower than that of group 2. The roughness increased significantly after coarse grinding in both groups. The results after glazing were similar to those obtained after fine grinding for non-veneered zirconia. However, fine-ground veneered zirconia had significantly higher roughness than venerred, glazed zirconia. No significant difference was found between fine-polished and glazed zirconia, but after the fine polishing of veneered zirconia, the roughness was significantly higher than after glazing. It can be concluded that for full-contour zirconia, fewer defects and lower roughness values resulted after grinding and polishing compared to veneered zirconia. After polishing zirconia, lower roughness values were achieved compared to glazing; more interesting was that the grinding of glazed zirconia using the NTI three-step system could deliver smooth surfaces comparable to untreated glazed zirconia surfaces.

  17. Drying characteristics of hui ink at 25 °C and 35 °C

    Science.gov (United States)

    Fu, Yang; Yao, Yao; Liu, Le; Wang, Fengwen; Yang, Shuyun

    2018-05-01

    Temperature and humidity are the main factors affecting the drying of Hui ink. For the experiment, fresh Hui ink billets from two big ink industries were selected. We tried to find the fast and efficient drying conditions of Hui ink and calculate effective diffusion coefficient by performing manual control of temperature and relative humidity (RH). Several dry kinetic models were fitted. A constant temperature incubator was utilized for temperature control, while humidification and dehumidification were implemented accordingly for RH control. Setups of 25 °C and 35 °C were designed, and a relative humidity of 60%, 65%, 70%, and 75% was applied for each temperature. The process of ink drying was recorded, and the drying effect of Hui ink was estimated through expert decision. The appropriate drying temperature and humidity of the Jinbuhuan(J) and Huangshansongyan(H) ink billets from Lao Hu Kai Wen Ink Industry are at (31.99 ± 1.41) °C and (55.84 ± 10.38)% RH, whereas those of the Songyantanhei(ST), Chunyouyan(CY), and Quansongyan(QS) ink billets from Ju Mo Tang Ink Industry are at (23.70 ± 2.19) °C and (60.56 ± 2.16)% RH or (34.56 ± 2.37) °C and (59.16 ± 6.38)% RH; Initial moisture content of Hui ink has great influence on the water loss in the drying process; The effective diffusion coefficient of the ink lump ranges from 8.41538E-07 to 1.95891E-06 m2·s-1, and increases mainly with the temperature's rising; Logarithmic model fits best of the chosen models.

  18. INK4 proteins, a family of mammalian CDK inhibitors with novel biological functions.

    Science.gov (United States)

    Cánepa, Eduardo T; Scassa, María E; Ceruti, Julieta M; Marazita, Mariela C; Carcagno, Abel L; Sirkin, Pablo F; Ogara, María F

    2007-07-01

    The cyclin D-Cdk4-6/INK4/Rb/E2F pathway plays a key role in controlling cell growth by integrating multiple mitogenic and antimitogenic stimuli. The members of INK4 family, comprising p16(INK4a), p15(INK4b), p18(INK4c), and p19(INK4d), block the progression of the cell cycle by binding to either Cdk4 or Cdk6 and inhibiting the action of cyclin D. These INK4 proteins share a similar structure dominated by several ankyrin repeats. Although they appear to be structurally redundant and equally potent as inhibitors, the INK4 family members are differentially expressed during mouse development. The striking diversity in the pattern of expression of INK4 genes suggested that this family of cell cycle inhibitors might have cell lineage-specific or tissue-specific functions. The INK4 proteins are commonly lost or inactivated by mutations in diverse types of cancer, and they represent established or candidate tumor suppressors. Apart from their capacity to arrest cells in the G1-phase of the cell cycle they have been shown to participate in an increasing number of cellular processes. Given their emerging roles in fundamental physiological as well as pathological processes, it is interesting to explore the diverse roles for the individual INK4 family members in different functions other than cell cycle regulation. Extensive studies, over the past few years, uncover the involvement of INK4 proteins in senescence, apoptosis, DNA repair, and multistep oncogenesis. We will focus the discussion here on these unexpected issues.

  19. A stretchable and screen-printable conductive ink for stretchable electronics

    Science.gov (United States)

    Mohammed, Anwar; Pecht, Michael

    2016-10-01

    Stretchable electronics can offer an added degree of design freedom and generate products with unprecedented capabilities. Stretchable conductive ink serving as interconnect, is a key enabler for stretchable electronics. This paper focuses on the development of a stretchable and screen printable conductive ink which could be stretched more than 500 cycles at 20% strain while maintaining electrical and mechanical integrity. The screen printable and stretchable conductive ink developed in this paper marks an important milestone for this nascent technology.

  20. Electrical and Physical Property Characterization of Single Walled Carbon Nanotube Ink for Flexible Printed Electronics

    Science.gov (United States)

    2015-03-01

    accurately can the 2 ink be printed? How well does the ink adhere to its substrate? How does the substrate affect the adhesion properties? In what...physical characteristics, some of which may be incompatible with inkjet printing, or the Dimatix DMP 2800 specifically. 3.2.1.2 Ink Solvent...The tape test is conducted by applying a flexible adhesive -backed polymer to the fully-dried printed circuit. The tape is then removed and analyzed

  1. EFFECTIVE ELASTIC PROPERTIES OF ALUMINA-ZIRCONIA COMPOSITE CERAMICS - PART 4. TENSILE MODULUS OF POROUS ALUMINA AND ZIRCONIA

    Directory of Open Access Journals (Sweden)

    W. Pabst

    2004-12-01

    Full Text Available In this fourth paper of a series on the effective elastic properties of alumina-zirconia composite ceramics the influence of porosity on the effective tensile modulus of alumina and zirconia ceramics is discussed. The examples investigated are alumina and zirconia ceramics prepared from submicron powders by starch consolidation casting using two different types of starch, potato starch (median size D50 =47.2 µm and corn starch (median size D50 =13.7 µm. The dependence of effective tensile moduli E, on the porosity f, measured for porosities in the ranges of approx. 19-55 vol.% and 10-42 vol.% for alumina and zirconia, respectively, using a resonant frequency technique, was evaluated by fitting with various model relations, including newly developed ones. A detailed comparison of the fitting results suggests the superiority of the new relation E/E0 = (1 - f·(1 - f/fC, developed by the authors (with the tensile modulus of the dense ceramic material E0 and the critical porosity fC, over most other existing fit models. Only for special purposes and well-behaved data sets the recently proposed exponential relation E/E0 = exp [-Bf/(1 - f] and the well-known Phani-Niyogi relation E/E0 = (1 - f/fCN might be preferable.

  2. An electroluminescence device for printable electronics using coprecipitated ZnS:Mn nanocrystal ink

    International Nuclear Information System (INIS)

    Toyama, T; Hama, T; Adachi, D; Nakashizu, Y; Okamoto, H

    2009-01-01

    Electroluminescence (EL) devices for printable electronics using coprecipitated ZnS:Mn nanocrystal (NC) ink are demonstrated. The EL properties of these devices were investigated along with the structural and optical properties of ZnS:Mn NCs with an emphasis on their dependence on crystal size. Transmission electron microscopy and x-ray diffraction studies revealed that the NCs, with a crystal size of 3-4 nm, are nearly monodisperse; the crystal size can be controlled by the Zn 2+ concentration in the starting solution for coprecipitation. The results of optical studies indicate the presence of quantum confinement effects; in addition, the NC surfaces are well passivated, regardless of the crystal size. Finally, an increase in the luminance of EL devices with a decrease in crystal size is observed, which suggests the excitation mechanism of ZnS:Mn NC EL devices.

  3. Thermal Analysis of Braille Formed by Using Screen Printing and Inks with Thermo Powder

    Directory of Open Access Journals (Sweden)

    Svіtlana HAVENKO

    2015-03-01

    Full Text Available In order to improve the integration of blind people into society, suitable conditions should be provided for them. The expansion of Braille (BR use could serve the purpose. Depending on the materials used for Braille, it can be formed or printed in different ways: embossing, screen printing, thermoforming, digital printing. The aim of this research is to determine the effect of thermal properties of screen printing inks and inks with thermo-powder on the qualitative parameters of Braille. Screen printing inks and inks with thermo-powder were chosen for the research. Carrying out the qualitative analysis of printouts with Braille, the thermal stability was evaluated by analyzing the thermograms obtained with derivatograph Q-1500. This paper presents the findings of the thermogravimetric (TG, differential thermogravimetric (DTG and differential thermal analysis (DTA of printouts printed on paperboard Plike and using traditional screen printing inks and screen printing inks with thermo-powder. Based on the testing findings it is determined that thermal stability of printouts printed with thermo-powder ink is higher than printed with screen printing inks. It is determined that the appropriate temperature range of screen printing inks with thermo-powder drying is 98 ºC – 198 ºC because in this case better relief of Braille dots is obtained.DOI: http://dx.doi.org/10.5755/j01.ms.21.1.5702

  4. Analysis of writing inks on paper using direct analysis in real time mass spectrometry.

    Science.gov (United States)

    Jones, Roger W; McClelland, John F

    2013-09-10

    Ink analysis is central to questioned document examination. We applied direct analysis in real time mass spectrometry (DART MS) to ballpoint, gel, and fluid writing ink analysis. DART MS acquires the mass spectrum of an ink while it is still on a document without altering the appearance of the document. Spectra were acquired from ink on a variety of papers, and the spectrum of the blank paper could be subtracted out to produce a cleanly isolated ink spectrum in most cases. Only certain heavy or heavily processed papers interfered. The time since an ink is written on paper has a large effect on its spectrum. DART spectra change radically during the first few months after an ink is written as the more volatile components evaporate, but the spectra stabilize after that. A library-search study involving 166 well-aged inks assessed the ability to identify inks from their DART spectra. The aggregate success rate was 92%. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  5. Investigation into the Friction and Roughness Properties of Prints Using Conventional and UV Inks

    Directory of Open Access Journals (Sweden)

    Giedrė Giraitytė

    2015-03-01

    Full Text Available The article experimentally investigates the properties of offset print friction and determines static and kinetic coeffi­cients of friction. Conventional and UV inks have been found to increase the static friction coefficient and re­duce the kinetic friction coefficient between paper and print. The roughness pro­perties of two different types of paper and prints using conventional and UV inks have been examined and compared thus determining that conventional inks strongly increase the roughness of print surface and that the influence of UV inks depend on the type of paper.

  6. Development of black ink for calligraphy purpose in the production of Al-quran

    Science.gov (United States)

    Rahim, F. F. A.; Jai, J.; Hamzah, F.; Bakar, N. F. A.

    2018-03-01

    Commercialised calligraphy inks are currently formulated for general purposes and is not to be practiced solely for the writings of Al-Quran. Thus the usage on Al-Quran is uncertain due to the unknown ingredients used. The virtue of this work is to develop halal and genuine formulations of black inks for calligraphy purpose in the production of Al-Quran manuscript. The black ink produced is required to have few properties; rich solid black, soft handling, fast drying time, non-lifting, non-feathering and waterproof. Pigment used include graphene, charcoal and lampblack. The binders are shellac and acrylic emulsion while solvent used are glycerol and ethanol. From the chosen pigments, binders and solvent, 19 formulation of inks were developed by manipulating the type and amount of each element. Evaluation of all 19 inks produced were done by an expert calligrapher using a professional scale. From the evaluation, one ink was chosen to have the best characteristics of an ink (ink code S9) with formulation of 0.3 g lampblack and 13 mL shellac. The produced black ink has fulfilled the requirement by the calligraphy expert.

  7. Self-reduction of a copper complex MOD ink for inkjet printing conductive patterns on plastics.

    Science.gov (United States)

    Farraj, Yousef; Grouchko, Michael; Magdassi, Shlomo

    2015-01-31

    Highly conductive copper patterns on low-cost flexible substrates are obtained by inkjet printing a metal complex based ink. Upon heating the ink, the soluble complex, which is composed of copper formate and 2-amino-2-methyl-1-propanol, decomposes under nitrogen at 140 °C and is converted to pure metallic copper. The decomposition process of the complex is investigated and a suggested mechanism is presented. The ink is stable in air for prolonged periods, with no sedimentation or oxidation problems, which are usually encountered in copper nanoparticle based inks.

  8. Hyperspectral imaging technology for revealing the original handwritings covered by the same inks

    Directory of Open Access Journals (Sweden)

    Yuanyuan Lian

    2017-01-01

    Full Text Available This manuscript presents a preliminary investigation on the applicability of hyperspectral imaging technology for nondestructive and rapid analysis to reveal covered original handwritings. The hyperspectral imager Nuance-Macro was used to collect the reflected light signature of inks from the overlapping parts. The software Nuance1p46 was used to analyze the reflected light signature of inks which shows the covered original handwritings. Different types of black/blue ballpoint pen inks and black/blue gel pen inks were chosen for sample preparation. From the hyperspectral images examined, the covered original handwritings of application were revealed in 90.5%, 69.1%, 49.5%, and 78.6% of the cases. Further, the correlation between the revealing effect and spectral characteristics of the reflected light of inks at the overlapping parts was interpreted through theoretical analysis and experimental verification. The results indicated that when the spectral characteristics of the reflected light of inks at the overlapping parts were the same or very similar to that of the ink that was used to cover the original handwriting, the original handwriting could not be shown. On the contrary, when the spectral characteristics of the reflected light of inks at the overlapping parts were different to that of the ink that was used to cover the original handwriting, the original handwriting was revealed.

  9. Different types of inks having certain medicolegal importance: Deciphering the faded and physically erased handwriting

    Directory of Open Access Journals (Sweden)

    Manal Abd-ElAziz Abd-ElZaher

    2014-06-01

    Full Text Available Disappearing ink is a type of ink which could be used to forge documents as it will fade away without any trace within 40–65 h. Erasable ink is another type of ink easily removed by certain rubbers incorporated in each pen. Both types of inks were applied separately on different types of papers (checks, standard white foolscap, and plain white A4 paper. For vanishing ink, it was observed visually in the first 6 h and then every 6 h. It was found that the vanishing ink disappeared completely within 2 h on checks, 36 h on standard white foolscap paper, and 40 h on plain white A4 paper. For erasable ink, the written strokes were manipulated manually using the incorporated eraser. Deciphering the faded writing failed by the conventional methods, but oblique light can reveal the indentation marks. The faded writing became visible when treated with weak alkaline (NaOH solutions. Erasable ink was deciphered with the aid of infra-red radiation combined with VSC-6000 as clear white traces against red fluorescence. It was concluded that the use of a weak (NaOH solution is an effective method for revealing the faded writing, and the infra-red illumination is also effective.

  10. Assessing Ink Transfer Performance of Gravure-Offset Fine-Line Circuitry Printing

    Science.gov (United States)

    Cheng, Hsien-Chie; Chen, You-Wei; Chen, Wen-Hwa; Lu, Su-Tsai; Lin, Shih-Ming

    2018-03-01

    In this study, the printing mechanism and performance of gravure-offset fine-line circuitry printing technology are investigated in terms of key printing parameters through experimental and theoretical analyses. First, the contact angles of the ink deposited on different substrates, blankets, and gravure metal plates are experimentally determined; moreover, their temperature and solvent content dependences are analyzed. Next, the ink solvent absorption and evaporation behaviors of the blankets at different temperatures, times, and numbers of printing repetitions are characterized by conducting experiments. In addition, while printing repeatedly, the surface characteristics of the blankets, such as the contact angle, vary with the amount of absorbed ink solvent, further affecting the ink transfer performance (ratio) and printing quality. Accordingly, the surface effect of the blanket due to ink solvent absorption on the ink contact angle is analyzed. Furthermore, the amount of ink transferred from the gravure plate to the blanket in the "off process" and from the blanket to the substrate in the "set process" is evaluated by conducting a simplified plate-to-plate experiment. The influences of loading rate (printing velocity), temperature, and solvent content on the ink transfer performance are addressed. Finally, the ink transfer mechanism is theoretically analyzed for different solvent contents using Surface Evolver. The calculation results are compared with those of the experiment.

  11. A microband lactate biosensor fabricated using a water-based screen-printed carbon ink.

    Science.gov (United States)

    Rawson, F J; Purcell, W M; Xu, J; Pemberton, R M; Fielden, P R; Biddle, N; Hart, J P

    2009-01-15

    The present study demonstrated for the first time that screen-printed carbon microband electrodes fabricated from water-based ink can readily detect H(2)O(2) and that the same ink, with the addition of lactate oxidase, can be used to construct microband biosensors to measure lactate. These microband devices were fabricated by a simple cutting procedure using conventional sized screen-printed carbon electrodes (SPCEs) containing the electrocatalyst cobalt phthalocyanine (CoPC). These devices were characterised with H(2)O(2) using several electrochemical techniques. Cyclic voltammograms were found to be sigmoidal; a current density value of 4.2 mA cm(-2) was obtained. A scan rate study revealed that the mass transport mechanism was a mixture of radial and planar diffusion. However, a further amperometric study under quiescent and hydrodynamic conditions indicated that radial diffusion predominated. A chronoamperometric study indicated that steady-state currents were obtained with these devices for a variety of H(2)O(2) concentrations and that the currents were proportional to the analyte concentration. Lactate microband biosensors were then fabricated by incorporating lactate oxidase into the water-based formulation prior to printing and then cutting as described. Voltammograms demonstrated that lactate oxidase did not compromise the integrity of the electrode for H(2)O(2) detection. A potential of +400 mV was selected for a calibration study, which showed that lactate could be measured over a dynamic range of 1-10mM which was linear up to 6mM; a calculated lower limit of detection of 289 microM was ascertained. This study provides a platform for monitoring cell metabolism in-vitro by measuring lactate electrochemically via a microband biosensor.

  12. Electrical conductivity of zirconia and yttrium-doped zirconia from Indonesian local zircon as prospective material for fuel cells

    International Nuclear Information System (INIS)

    Apriany, Karima; Permadani, Ita; Rahmawati, Fitria; Syarif, Dani G.; Soepriyanto, Syoni

    2016-01-01

    In this research, zirconium dioxide, ZrO 2 , was synthesized from high-grade zircon sand that was founded from Bangka Island, Sumatra, Indonesia. The zircon sand is a side product of Tin mining plant industry. The synthesis was conducted by caustic fusion method with considering definite stoichiometric mole at every reaction step. Yttrium has been doped into the prepared zirconia by solid state reaction. The prepared materials were then being analyzed by X-ray diffraction equipped with Le Bail refinement to study its crystal structure and cell parameters. Electrical conductivity was studied through impedance measurement at a frequency range of 20 Hz- 5 MHz. Morphological analysis was conducted through Scanning Electron Microscopy (SEM) equipped with Energy Dispersive X-ray (EDX) for elemental analysis. The results show that the prepared yttrium stabilized zirconia, YSZ, was crystallized in the cubic structure with a space group of P42/NMC. The sintered zirconia and yttrium stabilized zirconia at 8 mol% of yttrium ions (8YSZ) show dense surface morphology with a grain size less than 10 pm. Elemental analysis on the sintered zirconia and 8YSZ show that sintering at 1500°C could eliminate the impurities, and the purity became 81.30%. Impedance analysis shows that ZrO 2 provide grain and grain boundary conductivity meanwhile 8YSZ only provide grain mechanism. The yttrium doping enhanced the conductivity up to 1.5 orders. The ionic conductivity of the prepared 8YSZ is categorized as a good material with conductivity reach 7.01 x10 -3 at 700 °C. The ionic conductivities are still lower than commercial 8YSZ at various temperature. It indicates that purity of raw material might significantly contribute to the electrical conductivity. (paper)

  13. Towards conducting inks: Polypyrrole–silver colloids

    International Nuclear Information System (INIS)

    Omastová, Mária; Bober, Patrycja; Morávková, Zuzana; Peřinka, Nikola; Kaplanová, Marie; Syrový, Tomáš; Hromádková, Jiřina; Trchová, Miroslava; Stejskal, Jaroslav

    2014-01-01

    Graphical abstract: - Highlights: • Composite colloidal particles combining conducting polymer and metal have been prepared. • Conducting colloids are suitable for printing applications. • Polypyrrole/silver colloids are prepared in a single reaction step. • The conductivity control is discussed and still needs improvement. - Abstract: The oxidation of pyrrole with silver nitrate in the presence of suitable water-soluble polymers yields composite polypyrrole–silver colloids. The polypyrrole–silver nanoparticles stabilized with poly(N-vinylpyrrolidone) have a typical size around 350 nm and polydispersity index 0.20, i.e. a moderate polydispersity in size. Similar results have been obtained with poly(vinyl alcohol) as stabilizer. The effect of stabilizer concentration on the particle size is marginal. In the present study, several types of stabilizers have been tested in addition to currently used poly(N-vinylpyrrolidone). Transmission electron microscopy and optical microscopy revealed the gemini morphology of polypyrrole and silver colloidal nanoparticles and confirmed their size and size-distribution determined by dynamic light scattering. The use of colloidal dispersions provides an efficient tool for the UV–vis and FT Raman spectroscopic characterization of polypyrrole, including the transition between polypyrrole salt and corresponding polypyrrole base. The dispersions were used for the preparation of coatings on polyethylene terephthalate foils, and the properties for polypyrrole–silver composites have been compared with those produced from polypyrrole colloids alone

  14. Shear bond strength of veneering porcelain to zirconia: Effect of surface treatment by CNC-milling and composite layer deposition on zirconia.

    Science.gov (United States)

    Santos, R L P; Silva, F S; Nascimento, R M; Souza, J C M; Motta, F V; Carvalho, O; Henriques, B

    2016-07-01

    The purpose of this study was to evaluate the shear bond strength of veneering feldspathic porcelain to zirconia substrates modified by CNC-milling process or by coating zirconia with a composite interlayer. Four types of zirconia-porcelain interface configurations were tested: RZ - porcelain bonded to rough zirconia substrate (n=16); PZ - porcelain bonded to zirconia substrate with surface holes (n=16); RZI - application of a composite interlayer between the veneering porcelain and the rough zirconia substrate (n=16); PZI - application of a composite interlayer between the porcelain and the zirconia substrate treated by CNC-milling (n=16). The composite interlayer was composed of zirconia particles reinforced porcelain (30%, vol%). The mechanical properties of the ceramic composite have been determined. The shear bond strength test was performed at 0.5mm/min using a universal testing machine. The interfaces of fractured and untested specimens were examined by FEG-SEM/EDS. Data was analyzed with Shapiro-Wilk test to test the assumption of normality. The one-way ANOVA followed by Tukey HSD multiple comparison test was used to compare shear bond strength results (α=0.05). The shear bond strength of PZ (100±15MPa) and RZI (96±11MPa) specimens were higher than that recorded for RZ (control group) specimens (89±15MPa), although not significantly (p>0.05). The highest shear bond strength values were recorded for PZI specimens (138±19MPa), yielding a significant improvement of 55% relative to RZ specimens (p<0.05). This study shows that it is possible to highly enhance the zirconia-porcelain bond strength - even by ~55% - by combining surface holes in zirconia frameworks and the application of a proper ceramic composite interlayer. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Biodiesel fuel production with solid amorphous-zirconia catalysis in fixed bed reactor

    International Nuclear Information System (INIS)

    Furuta, Satoshi; Matsuhashi, Hiromi; Arata, Kazushi

    2006-01-01

    Amorphous zirconia catalysts, titanium-, aluminum-, and potassium-doped zirconias, were prepared and evaluated in the transesterification of soybean oil with methanol at 250 deg. C, and the esterification of n-octanoic acid with methanol at 175-200 deg. C. Titanium- and aluminum-doped zirconias are promising solid catalysts for the production of biodiesel fuels from soybean oil because of their high performance, with over 95% conversion in both of the esterifications

  16. Ink dating part II: Interpretation of results in a legal perspective.

    Science.gov (United States)

    Koenig, Agnès; Weyermann, Céline

    2018-01-01

    The development of an ink dating method requires an important investment of resources in order to step from the monitoring of ink ageing on paper to the determination of the actual age of a questioned ink entry. This article aimed at developing and evaluating the potential of three interpretation models to date ink entries in a legal perspective: (1) the threshold model comparing analytical results to tabulated values in order to determine the maximal possible age of an ink entry, (2) the trend tests that focusing on the "ageing status" of an ink entry, and (3) the likelihood ratio calculation comparing the probabilities to observe the results under at least two alternative hypotheses. This is the first report showing ink dating interpretation results on a ballpoint be ink reference population. In the first part of this paper three ageing parameters were selected as promising from the population of 25 ink entries aged during 4 to 304days: the quantity of phenoxyethanol (PE), the difference between the PE quantities contained in a naturally aged sample and an artificially aged sample (R NORM ) and the solvent loss ratio (R%). In the current part, each model was tested using the three selected ageing parameters. Results showed that threshold definition remains a simple model easily applicable in practice, but that the risk of false positive cannot be completely avoided without reducing significantly the feasibility of the ink dating approaches. The trend tests from the literature showed unreliable results and an alternative had to be developed yielding encouraging results. The likelihood ratio calculation introduced a degree of certainty to the ink dating conclusion in comparison to the threshold approach. The proposed model remains quite simple to apply in practice, but should be further developed in order to yield reliable results in practice. Copyright © 2017 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.

  17. Chemical composition of felt-tip pen inks.

    Science.gov (United States)

    Germinario, Giulia; Garrappa, Silvia; D'Ambrosio, Valeria; van der Werf, Inez Dorothé; Sabbatini, Luigia

    2018-01-01

    Felt-tip pens are frequently used for the realization of sketches, drawings, architectural projects, and other technical designs. The formulations of these inks are usually rather complex and may be associated to those of modern paint materials where, next to the binding medium and pigments/dyes, solvents, fillers, emulsifiers, antioxidants, plasticizers, light stabilizers, biocides, and so on are commonly added. Felt-tip pen inks are extremely sensitive to degradation and especially exposure to light may cause chromatic changes and fading. In this study, we report on the complete chemical characterization of modern felt-tip pen inks that are commercially available and commonly used for the realization of artworks. Three brands of felt-tip pens (Faber-Castell, Edding, and Stabilo) were investigated with complementary analytical techniques such as thin-layer chromatography (TLC), VIS-reflectance spectroscopy, μ-Raman spectroscopy, surface-enhanced Raman spectroscopy (SERS), pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), GC-MS, and Fourier transform infrared (FTIR) spectroscopy. The use of TLC proved to be very powerful in the study of complex mixtures of synthetic dyes. First derivatives of the reflectance spectra acquired on the TLC spots were useful in the preliminary identification of the dye, followed by Raman spectroscopy and SERS, which allowed for the unambiguous determination of the chemical composition of the pigments (phthalocyanines, dioxazines, and azo pigments) and dyes (azo dyes, triarylmethanes, xanthenes). FTIR spectroscopy was used especially for the detection of additives, as well as for confirming the nature of solvents and dyes/pigments. Finally, (Py-)GC-MS data provided information on the binders (styrene-acrylic resins, plant gums), solvents, and additives, as well as on pigments and dyes.

  18. Screen-printing ink transfer in a sexual assault case.

    Science.gov (United States)

    Amick, Janeice F; Beheim, Chris W

    2002-05-01

    Yellow plastic-like particles were discovered on the clothing and body of a sexual assault victim. These particles were later associated to an athletic jersey with flaking yellow screen-printed numbers and letters, worn by the suspect. Depending on its intended substrate, screen-print ink can vary in color and composition. Particles dislodged from screen-printed garments may exhibit fabric impressions. Screen-printed clothing, commonly encountered in forensic casework, should be viewed as a potential source of trace evidence.

  19. Functional inks and printing of two-dimensional materials.

    Science.gov (United States)

    Hu, Guohua; Kang, Joohoon; Ng, Leonard W T; Zhu, Xiaoxi; Howe, Richard C T; Jones, Christopher G; Hersam, Mark C; Hasan, Tawfique

    2018-05-08

    Graphene and related two-dimensional materials provide an ideal platform for next generation disruptive technologies and applications. Exploiting these solution-processed two-dimensional materials in printing can accelerate this development by allowing additive patterning on both rigid and conformable substrates for flexible device design and large-scale, high-speed, cost-effective manufacturing. In this review, we summarise the current progress on ink formulation of two-dimensional materials and the printable applications enabled by them. We also present our perspectives on their research and technological future prospects.

  20. Determining the coating speed limitations for organic photovoltaic inks

    DEFF Research Database (Denmark)

    Jakubka, Florian; Heyder, Madeleine; Machui, Florian

    2013-01-01

    To determine the output capability of present organic photovoltaic (OPV) materials, it is important to know the theoretical maximum coating speeds of the used semiconductor formulations. Here, we present a comprehensive investigation of the coating stability window of several prototype organic...... semiconductor inks relevant for organic solar cells. The coating stability window was first determined experimentally by a sheet to sheet coater at velocities of up to 10 m/min. A numerical simulation model based on the Coating Window Suite 2010 software was established to give insight into the coating...

  1. Preparation of stabilized zirconia (Zr O2) with Yttria (Y2 O3) by simultaneous precipitation

    International Nuclear Information System (INIS)

    Campos, M. de.

    1993-01-01

    The preparation of cubic or tetragonal partially stabilized zirconia with Yttria by simultaneous precipitation was studied. The metals Zr and Y, in nitric acid and hydrogen peroxide medium, were precipitated with ammonia solution. The variables studied were: the pH of the aqueous medium (8, 9 e 10) and yttrium molar concentration (2, 3 and 5 mol %) in the final product. The resulting oxide samples were divided and calcined at 500, 700 and 900 0 C, separately. After that, all samples were sintered at 1500 0 C for one hour. For physico-chemical characterization were used techniques such as: ICP-AES, XRF, XRD, SEM etc. The results have showed that using this approach predominant cubic and/or tetragonal phases can be reached with theoretical density over 92% and grain size lower than 1 μm. (author)

  2. Tribological and wear behavior of yttria stabilized zirconia thermal barrier coatings on mild steel

    International Nuclear Information System (INIS)

    Farooq, M.; Pervez, A.

    2012-01-01

    The perfection of the temperature confrontation of the engine essentials can be obtained by claim of a single ceramic thermal barrier coating (TBC) or several composite layers. Engine elements protected by TBC can work safely in elevated temperature range above 1000 degree C. Continuous endeavor to increase thermal resistance of engine the elements requires, apart from laboratory investigations, also numerical study of the different engine parts. The high temperatures and stress concentrations can act as the local sources of damage initiation and defects propagation in the form of cracks. The current study focuses the development of Yttria stabilized zirconia thermal barrier coating by Thermal spray technique. Mild steel was used as a substrate and the coating was then characterized for tribological analysis followed by the optical analysis of wear tracks and found the TBC behavior more promising then steel. (author)

  3. pH-responsive lyotropic liquid crystals for the preparation of pure cubic zirconia nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    He, Wei Yan; Liu, Jin Rong; He, Zhang; Cao, Zhen Zhu; Li, Cai Hong; Gao, Yan Fang [Inner Mongolia University of Technology, School of Chemical Engineering, Hohhot (China)

    2016-07-15

    We present a lyotropic liquid crystal system consisting of SDS/Triton X-100/water at 25 C. This system is respond to pH variations with a phase switch. When pH is altered from alkaline (pH 13) to acidic (pH 2) conditions, phase change occurs from a bicontinuous hexagonal phase to a partially hexagonal phase until it disappears. The hexagonal phase under alkaline conditions is stable. Thus, this system is an ideal candidate for the preparation of pure cubic ZrO{sub 2} nanoparticles. XRD results confirm that the as-synthesized powder is composed of pure cubic ZrO{sub 2}. These nanoparticles also exhibit a thermal stability of up to 800 C. The size and morphological characteristics of the nanoparticles are greatly affected by ZrOCl{sub 2} concentration. The mechanism of zirconia nanoparticle synthesis in a lyotropic hexagonal phase was proposed. (orig.)

  4. Effect of grinding and polishing on near-surface phase transformations in zirconia

    International Nuclear Information System (INIS)

    Reed, J.S.; Lejus, A.M.

    1977-01-01

    The transformation of near-surface material on grinding and polishing has been investigated in sintered zirconia of 1 μm grain size and 99 percent density containing 4.5 and 7.0 mole percent Y 2 O 3 . Rough wet and dry grinding transformed about 20 percent cubic phase into 18 percent tetragonal and 2 percent monoclinic in material initially 47 percent cubic and 53 percent tetragonal (4.5 mole percent Y 2 O 3 ) but no change of phase in material that was fully cubic (7.0 mole percent Y 2 O 3 ). Annealing and polishing reduced lattice strain but only polishing reduced the concentration of monoclinic and tetragonal phases. Microhardness studies indicated that lattice strain and the phase transformations increased the penetration hardness to a depth of about 4 μm

  5. Experimental study of stress-induced localized transformation plastic zones in tetragonal zirconia polycrystalline ceramics

    International Nuclear Information System (INIS)

    Sun, Q.; Zhao, Z.; Chen, W.; Qing, X.; Xu, X.; Dai, F.

    1994-01-01

    Stress-induced martensitic transformation plastic zones in ceria-stabilized tetragonal zirconia polycrystalline ceramics (Ce-TZP), under loading conditions of uniaxial tension, compression, and three-point bending, are studied by experiments. The transformed monoclinic phase volume fraction distribution and the corresponding plastic strain distribution and the surface morphology (surface uplift) are measured by means of moire interferometry, Raman microprobe spectroscopy, and the surface measurement system. The experimental results from the above three kinds of specimens and methods consistently show that the stress-induced transformation at room temperature of the above specimen is not uniform within the transformation zone and that the plastic deformation is concentrated in some narrow band; i.e., macroscopic plastic flow localization proceeds during the initial stage of plastic deformation. Flow localization phenomena are all observed in uniaxial tension, compression, and three-point bending specimens. Some implications of the flow localization to the constitutive modeling and toughening of transforming thermoelastic polycrystalline ceramics are explored

  6. A comparison of different silver inks for printing of conductive tracks on paper substrates for rapid prototyping of electronic circuits

    CSIR Research Space (South Africa)

    Bezuidenhout, PH

    2015-11-01

    Full Text Available This study compares the performance between two commercially-available electrically conductive silver inks, Harima NPS-J nanopaste and the NBSIJ-FD02 Mitsubishi conductive ink, used in rapid prototyping of electronic circuits. The comparative...

  7. AC plasma electrolytic oxidation of magnesium with zirconia nanoparticles

    International Nuclear Information System (INIS)

    Arrabal, R.; Matykina, E.; Viejo, F.; Skeldon, P.; Thompson, G.E.; Merino, M.C.

    2008-01-01

    The incorporation of monoclinic zirconia nanoparticles and their subsequent transformation is examined for coatings formed on magnesium by plasma electrolytic oxidation under AC conditions in silicate electrolyte. The coatings are shown to comprise two main layers, with nanoparticles entering the coating at the coating surface and through short-circuit paths to the region of the interface between the inner and outer coating layers. Under local heating of microdischarges, the zirconia reacts with magnesium species to form Mg 2 Zr 5 O 12 in the outer coating layer. Relatively little zirconium is present in the inner coating layer. In contrast, silicon species are present in both coating layers, with reduced amounts in the inner layer

  8. Properties of Formula 127 glass prepared with radioactive zirconia calcine

    International Nuclear Information System (INIS)

    Staples, B.A.; Pavlica, D.A.; Cole, H.S.

    1982-09-01

    Formula 127 glass has been developed to immobilize ICPP zirconia calcine. This glass has been prepared remotely on a laboratory scale basis with actual radioactive zirconia calcine retrieved after ten years of storage from Bin Set 2. The aqueous leachability of the glass produced was investigated and compared through application of the MCC-1, MCC-2 and Soxhlet leach tests with that of Formula 127 glass prepared with simulated calcine. The solid state properties of the glasses prepared with actual and simulated calcines were also measured by electron spectroscopy for chemical analysis (ESCA) and scanning electron microscopy energy dispersive x-ray (SEM-EDX). Based on the application of these leaching tests and analysis techniques the properties measured in this study are similar for 127 glass prepared with either simulated or radioactive calcine. 13 figures, 16 tables

  9. The development of Zirconia and Copper toughened Alumina ceramic insert

    Science.gov (United States)

    Amalina Sabuan, Nur; Zolkafli, Nurfatini; Mebrahitom, A.; Azhari, Azmir; Mamat, Othman

    2018-04-01

    Ceramic cutting tools have been utilized in industry for over a century for its productivity and efficiency in machine tools and cutting tool material. However, due to the brittleness property the application has been limited. In order to manufacture high strength ceramic cutting tools, there is a need for suitable reinforcement to improve its toughness. In this case, copper (Cu) and zirconia (ZrO2) powders were added to investigate the hardness and physical properties of the developed composite insert. A uniaxial pre-forming process of the mix powder was done prior to densification by sintering at 1000 and 1300°C. The effect of the composition of the reinforcement on the hardness, density, shrinkage and microstructure of the inserts was investigated. It was found that an optimum density of 3.26 % and hardness 1385HV was obtained for composite of 10wt % zirconia and 10wt% copper at temperature 1000 °C.

  10. The radiation response of mesoporous nanocrystalline zirconia thin films

    Energy Technology Data Exchange (ETDEWEB)

    Manzini, Ayelén M.; Alurralde, Martin A. [Comisión Nacional de Energía Atómica, Centro Atómico Constituyentes, Av. General Paz 1499, 1650 San Martin, Provincia de Buenos Aires (Argentina); Giménez, Gustavo [Instituto Nacional de Tecnología Industrial - CMNB, Av. General Paz 5445, 1650 San Martín, Provincia de Buenos Aires (Argentina); Luca, Vittorio, E-mail: vluca@cnea.gov.ar [Comisión Nacional de Energía Atómica, Centro Atómico Constituyentes, Av. General Paz 1499, 1650 San Martin, Provincia de Buenos Aires (Argentina)

    2016-12-15

    The next generation of nuclear systems will require materials capable of withstanding hostile chemical, physical and radiation environments over long time-frames. Aside from its chemical and physical stability, crystalline zirconia is one of the most radiation tolerant materials known. Here we report the first ever study of the radiation response of nanocrystalline and mesoporous zirconia and Ce{sup 3+}-stabilized nanocrystalline zirconia (Ce{sub 0.1}Zr{sub 0.9}O{sub 2}) thin films supported on silicon wafers. Zirconia films prepared using the block copolymer Brij-58 as the template had a thickness of around 60–80 nm. In the absence of a stabilizing trivalent cation they consisted of monoclinic and tetragonal zirconia nanocrystals with diameters in the range 8–10 nm. Films stabilized with Ce{sup 3+} contained only the tetragonal phase. The thin films were irradiated with iodine ions of energies of 70 MeV and 132 keV at low fluences (10{sup 13} - 10{sup 14} cm{sup −2}) corresponding to doses of 0.002 and 1.73 dpa respectively, and at 180 keV and high fluences (2 × 10{sup 16} cm{sup −2}) corresponding to 82.4 dpa. The influence of heavy ion irradiation on the nanocrystalline structure was monitored through Rietveld analysis of grazing incidence X-ray diffraction (GIXRD) patterns recorded at angles close to the critical angle to ensure minimum contribution to the diffraction pattern from the substrate. Irradiation of the mesoporous nanocrystalline zirconia thin films with 70 MeV iodine ions, for which electronic energy loss is dominant, resulted in slight changes in phase composition and virtually no change in crystallographic parameters as determined by Rietveld analysis. Iodine ion bombardment in the nuclear energy loss regime (132–180 keV) at low fluences did not provoke significant changes in phase composition or crystallographic parameters. However, at 180 keV and high fluences the monoclinic phase was totally eliminated from the GIXRD

  11. Making innovative tattoo ink products with improved safety: possible and impossible ingredients in practical usage.

    Science.gov (United States)

    Dirks, Michael

    2015-01-01

    Today's tattoo inks are no longer just simple solids in liquid suspension. Nowadays, these inks are high-tech dispersions made from finely spread pigments in a binder-solvent mixture. These so-called colour dispersions must follow the modern standards of tattooing, which are increasing every year. They must be rich in chromophoric pigments and yet fluid, they must not dry rapidly, and there should be no occurrence of any sedimentation, even during longer tattoo seasons. An innovative tattoo ink should enable long-lasting, brilliant tattoos without a negative impact on the artist's workflow and of course without endangering the consumer. The high standard in tattoos, regarding the motives and techniques, that is witnessed today could not be achieved by the artists without quality tools and modern tattoo ink. This article will give the reader a brief overview of the different ingredients of tattoo ink and of the function of binding agents and solvents in modern tattoo ink as well as describe what additives are used to achieve the desired behaviour during application. Furthermore, the article will take a look into the pigments that are used in tattoo ink and show why certain pigments are not suited for tattoo ink. The differences, advantages and disadvantages of organic and inorganic pigments will be explained. © 2015 S. Karger AG, Basel.

  12. Model compounds of iron gall inks – a Mössbauer study

    International Nuclear Information System (INIS)

    Lerf, A.; Wagner, F. E.

    2016-01-01

    Ferrogallic inks were used for at least two millennia before they became obsolete in the 20 th century. The chemistry of such inks is, however, still largely unclear. Today it is of particular interest for the conservation of old manuscripts. 57 Fe Mössbauer spectra of the ink on historical documents showed the presence of Fe(II) oxalate and of Fe(III) sites presumably representing iron oxihydroxides. To obtain more information on the behaviour of ink on paper we have performed Mössbauer studies at 300 and 4.2 K on iron gall inks prepared from FeSO 4 ⋅7H 2 O and tannin. These inks were either written on paper or isolated as a precipitate by centrifugation. In the dried precipitate there is still a strong contribution of the FeSO 4 ⋅7H 2 O which is absent in the same ink written on paper, for which a broad ferrous component with a quadrupole splitting (QS) of about 2.5 mm/s was found. The dominant Fe(III) site present in all inks on paper with QS ≈ 0.82 mm/s is not Fe(III) gallate and different from the precipitates. We propose that nanoparticulate oxidic clusters or molecular composites covered by a shell of polymerized oxidation products of the phenols are formed on the paper.

  13. Silver-organo-complex ink with high conductivity and inkjet stability

    KAUST Repository

    Vaseem, Mohammad

    2017-06-22

    A robust formulation of silver-organo-complex (SOC) ink and method of making same are provided. In an aspect, the complexing molecules act as reducing agents. The silver loaded ink can be printed and sintered on a wide range of substrates with uniform surface morphology and excellent adhesion.

  14. A fully printed ferrite nano-particle ink based tunable antenna

    KAUST Repository

    Ghaffar, Farhan A.; Vaseem, Mohammad; Shamim, Atif

    2016-01-01

    on conventional microwave substrates. In order to have a fully printed fabrication process, the substrate also need to be printed. In this paper, a fully printed multi-layer process utilizing custom Fe2O3 based magnetic ink and a silver organic complex (SOC) ink

  15. Model compounds of iron gall inks – a Mössbauer study

    Energy Technology Data Exchange (ETDEWEB)

    Lerf, A. [Bavarian Academy of Sciences, Walther Meißner Institute (Germany); Wagner, F. E., E-mail: fwagner@tum.de [Technical University of Munich, Physics Department E15 (Germany)

    2016-12-15

    Ferrogallic inks were used for at least two millennia before they became obsolete in the 20{sup th} century. The chemistry of such inks is, however, still largely unclear. Today it is of particular interest for the conservation of old manuscripts. {sup 57}Fe Mössbauer spectra of the ink on historical documents showed the presence of Fe(II) oxalate and of Fe(III) sites presumably representing iron oxihydroxides. To obtain more information on the behaviour of ink on paper we have performed Mössbauer studies at 300 and 4.2 K on iron gall inks prepared from FeSO{sub 4}⋅7H{sub 2}O and tannin. These inks were either written on paper or isolated as a precipitate by centrifugation. In the dried precipitate there is still a strong contribution of the FeSO{sub 4}⋅7H{sub 2}O which is absent in the same ink written on paper, for which a broad ferrous component with a quadrupole splitting (QS) of about 2.5 mm/s was found. The dominant Fe(III) site present in all inks on paper with QS ≈ 0.82 mm/s is not Fe(III) gallate and different from the precipitates. We propose that nanoparticulate oxidic clusters or molecular composites covered by a shell of polymerized oxidation products of the phenols are formed on the paper.

  16. Nucleophilic stabilization of water-based reactive ink for titania-based thin film inkjet printing

    DEFF Research Database (Denmark)

    Gadea, Christophe; Marani, Debora; Esposito, Vincenzo

    2017-01-01

    Drop on demand deposition (DoD) of titanium oxide thin films (<500 nm) is performed via a novel titanium-alkoxide-based solution that is tailored as a reactive ink for inkjet printing. The ink is developed as water-based solution by a combined use of titanium isopropoxide and n-methyldiethanolami...

  17. Ink jet technology for large area organic light-emitting diode and organic photovoltaic applications

    NARCIS (Netherlands)

    Ren, M.; Gorter, H.; Michels, J.; Andriessen, R.

    2011-01-01

    Due to its flexibility and ease of patterning, ink jet printing has become a popular technique for the noncontact deposition of liquids, solutions, and melts on a variety of substrates at lateral resolutions down to 10 μm. This article presents a study of ink jet printing of homogeneous layers of

  18. Silver-organo-complex ink with high conductivity and inkjet stability

    KAUST Repository

    Vaseem, Mohammad; McKerricher, Garret; Shamim, Atif

    2017-01-01

    A robust formulation of silver-organo-complex (SOC) ink and method of making same are provided. In an aspect, the complexing molecules act as reducing agents. The silver loaded ink can be printed and sintered on a wide range of substrates with uniform surface morphology and excellent adhesion.

  19. Description of development of an analytical method for measurement of PAA in tattoo ink and PMU

    DEFF Research Database (Denmark)

    Lassen, Pia

    This review gives a background on azo pigments and primary aromatic amines (PAA) and describe how to develop a robust method for analyzing these in tattoo ink.......This review gives a background on azo pigments and primary aromatic amines (PAA) and describe how to develop a robust method for analyzing these in tattoo ink....

  20. Iron Oxide Nanoparticle-Based Magnetic Ink Development for Fully Printed Tunable Radio-Frequency Devices

    KAUST Repository

    Vaseem, Mohammad

    2018-01-30

    The field of printed electronics is still in its infancy and most of the reported work is based on commercially available nanoparticle-based metallic inks. Although fully printed devices that employ dielectric/semiconductor inks have recently been reported, there is a dearth of functional inks that can demonstrate controllable devices. The lack of availability of functional inks is a barrier to the widespread use of fully printed devices. For radio-frequency electronics, magnetic materials have many uses in reconfigurable components but rely on expensive and rigid ferrite materials. A suitable magnetic ink can facilitate the realization of fully printed, magnetically controlled, tunable devices. This report presents the development of an iron oxide nanoparticle-based magnetic ink. First, a tunable inductor is fully printed using iron oxide nanoparticle-based magnetic ink. Furthermore, iron oxide nanoparticles are functionalized with oleic acid to make them compatible with a UV-curable SU8 solution. Functionalized iron oxide nanoparticles are successfully embedded in the SU8 matrix to make a magnetic substrate. The as-fabricated substrate is characterized for its magnetostatic and microwave properties. A frequency tunable printed patch antenna is demonstrated using the magnetic and in-house silver-organo-complex inks. This is a step toward low-cost, fully printed, controllable electronic components.

  1. Synthesis and characterization of zirconia electrolytes for potential use in energy conversion

    International Nuclear Information System (INIS)

    Wheat, T.A.

    1978-11-01

    The present work is part of a program to develop ionically conducting materials for potential use in energy storage and conversion systems. With applications in high energy-density batteries, magneto-hydrodynamic (MHD) generators, fuel cells and sensors, they ae playing an increasinly important role in developing more efficient energy storage and conversion devices. Using a wet-chemical procedure, a series of compostions having between 0 and 22.2 mol percent CaO in zirconia, was prepared and subsequently formed into sintered samples having a relative density from 95 to 98 percent. Sintered samples were prepared of each composition with a geometry appropriate for determining the thermal, electrical or microstructural characteristics. This report covers only the microstructural aspects of powder synthesis and the development of sintered materials. Using the reactive, homogeneous, chemically prepared powders, it has been shown that cubic and monoclinic zirconia can coexist in compositions containing up to 10 mol percent CaO. From 10 to 20 mol percent CaO, only the cubic phase is formed, whereas at higher CaO concentrations the cubic phase coexits with CaZro 3 . The change from a two-phase to single-phase system as the CaO concentration is increased above 10 mol percent, increases the grain size nearly an order of magnitude. It has been found that 5 and 7.6 mol percent CaO materials develop considerable stress during the cooling stage of the firing cycle. As a result, they undergo a progressive and irreversible expansion with each thermal shock cycle: the magnitude of the expansion is proportional to the severity of the thermal shock. The microstructural texture of these partially stablilized materials was also shown to be dependent on the thermal history and hence a strong dependence of the electrical and thermal properties can be anticipated. (auth)

  2. Large scale synthesis of nanostructured zirconia-based compounds from freeze-dried precursors

    International Nuclear Information System (INIS)

    Gómez, A.; Villanueva, R.; Vie, D.; Murcia-Mascaros, S.; Martínez, E.; Beltrán, A.; Sapiña, F.; Vicent, M.; Sánchez, E.

    2013-01-01

    Nanocrystalline zirconia powders have been obtained at the multigram scale by thermal decomposition of precursors resulting from the freeze-drying of aqueous acetic solutions. This technique has equally made possible to synthesize a variety of nanostructured yttria or scandia doped zirconia compositions. SEM images, as well as the analysis of the XRD patterns, show the nanoparticulated character of those solids obtained at low temperature, with typical particle size in the 10–15 nm range when prepared at 673 K. The presence of the monoclinic, the tetragonal or both phases depends on the temperature of the thermal treatment, the doping concentration and the nature of the dopant. In addition, Rietveld refinement of the XRD profiles of selected samples allows detecting the coexistence of the tetragonal and the cubic phases for high doping concentration and high thermal treatment temperatures. Raman experiments suggest the presence of both phases also at relatively low treatment temperatures. - Graphical abstract: Zr 1−x A x O 2−x/2 (A=Y, Sc; 0≤x≤0.12) solid solutions have been prepared as nanostructured powders by thermal decomposition of precursors obtained by freeze-drying, and this synthetic procedure has been scaled up to the 100 g scale. Highlights: ► Zr 1−x A x O 2−x/2 (A=Y, Sc; 0≤x≤0.12) solid solutions have been prepared as nanostructured powders. ► The synthetic method involves the thermal decomposition of precursors obtained by freeze-drying. ► The temperature of the thermal treatment controls particle sizes. ► The preparation procedure has been scaled up to the 100 g scale. ► This method is appropriate for the large-scale industrial preparation of multimetallic systems.

  3. A new testing protocol for zirconia dental implants.

    Science.gov (United States)

    Sanon, Clarisse; Chevalier, Jérôme; Douillard, Thierry; Cattani-Lorente, Maria; Scherrer, Susanne S; Gremillard, Laurent

    2015-01-01

    Based on the current lack of standards concerning zirconia dental implants, we aim at developing a protocol to validate their functionality and safety prior their clinical use. The protocol is designed to account for the specific brittle nature of ceramics and the specific behavior of zirconia in terms of phase transformation. Several types of zirconia dental implants with different surface textures (porous, alveolar, rough) were assessed. The implants were first characterized in their as-received state by Scanning Electron Microscopy (SEM), Focused Ion Beam (FIB), X-Ray Diffraction (XRD). Fracture tests following a method adapted from ISO 14801 were conducted to evaluate their initial mechanical properties. Accelerated aging was performed on the implants, and XRD monoclinic content measured directly at their surface instead of using polished samples as in ISO 13356. The implants were then characterized again after aging. Implants with an alveolar surface presented large defects. The protocol shows that such defects compromise the long-term mechanical properties. Implants with a porous surface exhibited sufficient strength but a significant sensitivity to aging. Even if associated to micro cracking clearly observed by FIB, aging did not decrease mechanical strength of the implants. As each dental implant company has its own process, all zirconia implants may behave differently, even if the starting powder is the same. Especially, surface modifications have a large influence on strength and aging resistance, which is not taken into account by the current standards. Protocols adapted from this work could be useful. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  4. Porous Alumina and Zirconia Ceramics With Tailored Thermal Conductivity

    Czech Academy of Sciences Publication Activity Database

    Gregorová, E.; Pabst, W.; Sofer, Z.; Jankovský, O.; Matějíček, Jiří

    2012-01-01

    Roč. 395, č. 1 (2012), 012022-012022 ISSN 1742-6588. [European Thermal Sciences Conference (Eurotherm)/6./. Poitiers, 04.09.2012-07.09.2012] Institutional support: RVO:61389021 Keywords : Ceramics * alumina * zirconia * porosity * thermal conductivity * pore-forming agent * oxide ceramics * starch * porosity Subject RIV: JK - Corrosion ; Surface Treatment of Materials http://iopscience.iop.org/1742-6596/395/1/012022/pdf/1742-6596_395_1_012022.pdf

  5. Zirconia toughened mica glass ceramics for dental restorations.

    Science.gov (United States)

    Gali, Sivaranjani; K, Ravikumar; Murthy, B V S; Basu, Bikramjit

    2018-03-01

    The objective of the present study is to understand the role of yttria stabilized zirconia (YSZ) in achieving the desired spectrum of clinically relevant mechanical properties (hardness, elastic modulus, fracture toughness and brittleness index) and chemical solubility of mica glass ceramics. The glass-zirconia mixtures with varying amounts of YSZ (0, 5, 10, 15 and 20wt.%) were ball milled, compacted and sintered to obtain pellets of glass ceramic-YSZ composites. Phase analysis was carried out using X-ray diffraction and microstructural characterization with SEM revealed the crystal morphology of the composites. Mechanical properties such as Vickers hardness, elastic modulus, indentation fracture toughness and chemical solubility were assessed. Phase analysis of sintered pellets of glass ceramic-YSZ composites revealed the characteristic peaks of fluorophlogopite (FPP) and tetragonal zirconia. Microstructural investigation showed plate and lath-like interlocking mica crystals with embedded zirconia. Vickers hardness of 9.2GPa, elastic modulus of 125GPa, indentation toughness of 3.6MPa·m 1/2 , and chemical solubility of 30μg/cm 2 (well below the permissible limit) were recorded with mica glass ceramics containing 20wt.% YSZ. An increase in hardness and toughness of the glass ceramic-YSZ composites with no compromise on their brittleness index and chemical solubility has been observed. Such spectrum of properties can be utilised for developing a machinable ceramic for low stress bearing inlays, onlays and veneers. Copyright © 2018 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  6. Oxidation of mullite-zirconia-alumina-silicon carbide composites

    International Nuclear Information System (INIS)

    Baudin, C.; Moya, J.S.

    1990-01-01

    This paper reports the isothermal oxidation of mullite-alumina-zirconia-silicon carbide composites obtained by reaction sintering studied in the temperature interval 800 degrees to 1400 degrees C. The kinetics of the oxidation process was related to the viscosity of the surface glassy layer as well as to the crystallization of the surface film. The oxidation kinetics was halted to T ≤ 1300 degrees C, presumably because of crystallization

  7. Improvement of the steel quality through zirconia base ceramic filter

    International Nuclear Information System (INIS)

    Santos, Benedito M.; Foschini, Cesar R.; Santos, Ieda M.G.; Pinheiro, Adriano S.; Paskocimas, Carlos A.; Leite, Edson R.; Longo, Elson

    1997-01-01

    At the end of production, the steel presents inclusions own to the making process. Ceramics filters, with controlled porosity, are being produced to eliminate the impurities, so as to increase the good quality steel production. This work studies the optimization of the zirconia filters composition and production for siderurgical processes application. The study was done through the granulometric control, using BET, XRD and Hg Porosimetry. (author)

  8. Ionoluminscence of partially-stabilized zirconia for thermal barrier coatings

    International Nuclear Information System (INIS)

    Rebollo, N.R.; Ruvalcaba-Sil, J.L.; Miranda, J.

    2007-01-01

    Ionoluminescence is explored as an alternative technique to study the high temperature phase stability of zirconia-based oxides. The evolution of an initially metastable single tetragonal phase towards de-stabilization is investigated for three single-doped zirconia compositions with Y, Yb and Gd. The differences in de-stabilization paths are identified using X-ray diffraction and ionoluminescence; elemental analysis is also performed using particle-induced X-ray emission. X-ray diffraction studies reveal a different scenario for each of the compositions selected; the differences are strongly influenced by the thermodynamic driving forces associated to the fluorite-to-tetragonal displacive transformation. Ionoluminescence studies indicate a significant increment on the signal intensity for de-stabilized samples, relative to previous annealing stages. There are also more subtle differences in the luminescent response from the samples at intermediate annealing stages also related to phase changes. This study provides a basis to characterize phase evolution in single-doped zirconia compositions for thermal insulation applications using luminescence

  9. Crystal structures of sol-gel deposited zirconia thin films

    International Nuclear Information System (INIS)

    Bell, J.M.; Cheary, R.W.; Rice, M.; Ben-Nissan, B.; Cocking, J.L.; Johnstone, G.R.

    1992-01-01

    The authors reports on the crystal structure of zirconia thin films by high temperature x-ray diffraction. The films were deposited by sol-gel processing onto polished stainless steel substrates, and dried at 200 deg C. X-ray diffraction at temperatures between 400 deg C and 800 deg C was carried out using an APEX diffractometer with a position sensitive detector. Previous results indicated that there was a transformation between the tetragonal phase and the monoclinic phase at approximately 770 deg C. Two experiments have been carried out: temperature runs, where the structure evolution is studied as a function of temperature; and time evolution of the structure at fixed temperatures. The results for both experiments, including structural analysis of the different phases found in the thin zirconia films and an analysis of the kinetics of the phase transformation(s) from the time evolution work are presented. This will include a comparison with theories of nucleation and crystallisation in single element films. Impurity phases introduced by interaction of the zirconia with the substrate have been observed, and the effect of increasing annealing time on the substrate-film interaction will also be discussed. 17 refs., 1 tab., 3 figs

  10. Preparation of mesoporous zirconia microspheres as inert matrix

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Ting [State Key Laboratory of New Ceramics and Fine Processing, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084 (China); Wang, Chen; Lv, Jinlong [Beijing Key Laboratory of Fine Ceramics, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084 (China); Liang, Tongxiang, E-mail: txliang@tsinghua.edu.cn [State Key Laboratory of New Ceramics and Fine Processing, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084 (China)

    2016-12-01

    Mesoporous zirconia microspheres, with a diameter of 900 μm, were prepared as an inert accelerator driven system (ADS) transmutation element matrix by the sol-gel method. The purpose of mesopores is to improve the adsorption capacity of inert matrix fuel (IMF) for minor actinides. The study indicated that the mesoporous zirconia performance was improved after the microspheres were hydrothermally treated at 150 °C, the specific surface area increased from 28.29 m{sup 2}/g to 61.28 m{sup 2}/g, and hydrothermal treatment avoided the cracking of the microspheres. Pre-decomposition of the organics during the hydrothermal process stabilized the mesoporous structure. The average pore diameter of mesoporous microsphere was 14.3 nm. - Highlights: • Mesoporous zirconia microspheres with a diameter of 900 μm were prepared as ADS transmutation element inert matrix. • The mesoporous performance was improved after the microspheres were hydrothermally treated at 150 °C. • The specific surface area increased from 28.29 m{sup 2}/g to 61.28 m{sup 2}/g. • The hydrothermal treatment could avoid the cracking of the microspheres. • The specific surface area of mesoporous microsphere was 61.28 m{sup 2}/g and the average pore diameter was 14.3 nm.

  11. Mechanical properties of zirconia reinforced lithium silicate glass-ceramic.

    Science.gov (United States)

    Elsaka, Shaymaa E; Elnaghy, Amr M

    2016-07-01

    The aim of this study was to assess the mechanical properties of recently introduced zirconia reinforced lithium silicate glass-ceramic. Two types of CAD/CAM glass-ceramics (Vita Suprinity (VS); zirconia reinforced lithium silicate and IPS e.max CAD (IC); lithium disilicate) were used. Fracture toughness, flexural strength, elastic modulus, hardness, brittleness index, and microstructures were evaluated. Data were analyzed using independent t tests. Weibull analysis of flexural strength data was also performed. VS had significantly higher fracture toughness (2.31±0.17MPam(0.5)), flexural strength (443.63±38.90MPa), elastic modulus (70.44±1.97GPa), and hardness (6.53±0.49GPa) than IC (Pglass-ceramic revealed significantly a higher brittleness index (2.84±0.26μm(-1/2)) (lower machinability) than IC glass-ceramic (Pglass-ceramic revealed a lower probability of failure and a higher strength than IC glass-ceramic according to Weibull analysis. The VS zirconia reinforced lithium silicate glass-ceramic revealed higher mechanical properties compared with IC lithium disilicate glass-ceramic. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  12. Nature and strength of defect interactions in cubic stabilized zirconia

    International Nuclear Information System (INIS)

    Bogicevic, A.; Wolverton, C.

    2003-01-01

    The intrinsic ordering tendencies that limit ionic conduction in doped zirconia electrolytes are fully elucidated using first-principles calculations. A detailed analysis of nearly 300 yttria- and scandia-stabilized cubic-zirconia-ordered vacancy compounds reveals a delicate balance between competing elastic and electrostatic interactions. These results explain several outstanding experimental observations and provide substantial insight needed for improving ionic conduction and enabling low-temperature operation of zirconia-based electrolytes. We show that the surprising vacancy ordering in dilute solid solutions is a consequence of repulsive electrostatic and attractive elastic interactions that balance at third-neighbor vacancy separations. In contrast, repulsive elastic vacancy-dopant interactions prevail over electrostatic attraction at all probed defect separations in YSZ and lead to very weak ordering preferences in ScSZ. The total electronic contribution to the defect interactions is shown to be strongly dominated by simple point-charge electrostatics, leaving speciation of defect ordering for a given class of aliovalent dopants to the elastic term. Thus, ion size becomes a critical parameter in controlling the ionic conductivity of doped oxide electrolytes

  13. The analysis of ink jet printed eco-font efficiency

    Directory of Open Access Journals (Sweden)

    Rastko Milošević

    2016-07-01

    Full Text Available Utilization of eco-font for office printing is one of sustainable, “green” printing concepts, which besides obvious economic benefits, as a result has a certain effect on environmental sustainability as well. The fundamental problem that this practice faces is decreased quality of text printed using eco-fonts comparing to those printed with regular fonts. The aim of this research is eco-font efficiency estimation, i.e. determination of toner usage reduction level of ink jet printed documents typed with this font type, as well as estimation of the extent humans perceive differences between text printed with eco-font and the one printed by its „non-eco“ equivalent. Combining instrumental measuring method and digital image analysis, it was found that this simple principle (eco-font utilization enables substantial toner usage reduction for an ink jet printing system, while visual test showed that visual experience of text printed using eco-font is sufficient. In addition, awareness of benefits that eco-font utilization brings, change users’ attitude towards eco-font quality.

  14. Microvalve-based bioprinting - process, bio-inks and applications.

    Science.gov (United States)

    Ng, Wei Long; Lee, Jia Min; Yeong, Wai Yee; Win Naing, May

    2017-03-28

    Bioprinting is an emerging research field that has attracted tremendous attention for various applications; it offers a highly automated, advanced manufacturing platform for the fabrication of complex bioengineered constructs. Different bio-inks comprising multiple types of printable biomaterials and cells are utilized during the bioprinting process to improve the homology to native tissues and/or organs in a highly reproducible manner. This paper, presenting a first-time comprehensive yet succinct review of microvalve-based bioprinting, provides an in-depth analysis and comparison of different drop-on-demand bioprinting systems and highlights the important considerations for microvalve-based bioprinting systems. This review paper reports a detailed analysis of its printing process, bio-ink properties and cellular components on the printing outcomes. Lastly, this review highlights the significance of drop-on-demand bioprinting for various applications such as high-throughput screening, fundamental cell biology research, in situ bioprinting and fabrication of in vitro tissue constructs and also presents future directions to transform the microvalve-based bioprinting technology into imperative tools for tissue engineering and regenerative medicine.

  15. Emulsion Inks for 3D Printing of High Porosity Materials.

    Science.gov (United States)

    Sears, Nicholas A; Dhavalikar, Prachi S; Cosgriff-Hernandez, Elizabeth M

    2016-08-01

    Photocurable emulsion inks for use with solid freeform fabrication (SFF) to generate constructs with hierarchical porosity are presented. A high internal phase emulsion (HIPE) templating technique was utilized to prepare water-in-oil emulsions from a hydrophobic photopolymer, surfactant, and water. These HIPEs displayed strong shear thinning behavior that permitted layer-by-layer deposition into complex shapes and adequately high viscosity at low shear for shape retention after extrusion. Each layer was actively polymerized with an ultraviolet cure-on-dispense (CoD) technique and compositions with sufficient viscosity were able to produce tall, complex scaffolds with an internal lattice structure and microscale porosity. Evaluation of the rheological and cure properties indicated that the viscosity and cure rate both played an important role in print fidelity. These 3D printed polyHIPE constructs benefit from the tunable pore structure of emulsion templated material and the designed architecture of 3D printing. As such, these emulsion inks can be used to create ultra high porosity constructs with complex geometries and internal lattice structures not possible with traditional manufacturing techniques. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Causes and Recommendations for Unanticipated Ink Retention Following Tattoo Removal Treatment

    Science.gov (United States)

    Chen, Cynthia L.; Desai, Alpesh; Desai, Tejas

    2013-01-01

    While placement of ink into the skin is a long-standing tradition, patients are now seeking tattoo removal on a more frequent basis. Once considered acceptable removal options, tattoo ink removal via physical destruction included dermabrasion, chemical destruction, salabrasion, thermal destruction, and cryotherapy. Now these options are used extremely infrequently. These modalities provided unpredictable results and often required prolonged healing times and left patients with skin discoloration, pain, scarring, and ink retention. Even the widely adopted use of lasers, now considered the gold standard method, offers some level of unpredictability surrounding the natural progression of ink resolution. Multiple factors need to be taken into consideration when successfully removing tattoo pigment including the modalities used, number and frequency of treatments, proper device technique, and physiological barriers to tattoo removal. This paper serves to elucidate the common causes of ink retention following tattoo removal treatment with recommendations on how best to address this relatively common occurrence. PMID:23882312

  17. Identification of inks and structural characterization of contemporary artistic prints by laser-induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Oujja, M.; Vila, A.; Rebollar, E.; Garcia, J.F.; Castillejo, M.

    2005-01-01

    Identification of the inks used in artistic prints and the order in which different ink layers have been applied on a paper substrate are important factors to complement the classical stylistic aspects for the authentication of this type of objects. Laser-induced breakdown spectroscopy (LIBS) is investigated to determine the chemical composition and structural distribution of the constituent materials of model prints made by applying one or two layers of several blue and black inks on an Arches paper substrate. By using suitable laser excitation conditions, identification of the inks was possible by virtue of emissions from key elements present in their composition. Analysis of successive spectra on the same spot allowed the identification of the order in which the inks were applied on the paper. The results show the potential of laser-induced breakdown spectroscopy for the chemical and structural characterization of artistic prints

  18. 9 CFR 316.5 - Branding ink; to be furnished by official establishments; approval by Program; color.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Branding ink; to be furnished by... THEIR CONTAINERS § 316.5 Branding ink; to be furnished by official establishments; approval by Program... purpose shall be used to apply ink brands bearing official marks to carcasses of cattle, sheep, swine, or...

  19. INK128 Exhibits Synergy with Azoles against Exophiala spp. and Fusarium spp.

    Science.gov (United States)

    Gao, Lujuan; Sun, Yi; He, Chengyan; Li, Ming; Zeng, Tongxiang; Lu, Qiaoyun

    2016-01-01

    Infections of Exophiala spp. and Fusarium spp. are often chronic and recalcitrant. Systemic disseminations, which mostly occur in immunocompromised patients, are often refractory to available antifungal therapies. The conserved target of rapamycin (TOR) orchestrates cell growth and proliferation in response to nutrients and growth factors, which are important for pathogenicity and virulence. INK128 is a second-generation ATP-competitive TOR inhibitor, which binds the TOR catalytic domain and selectively inhibits TOR. In the present study, we investigated the in vitro activities of INK128 alone and the interactions of INK128 with conventional antifungal drugs including itraconazole, voriconazole, posaconazole, and amphotericin B against 18 strains of Exophiala spp. and 10 strains of Fusarium spp. via broth microdilution checkerboard technique system adapted from Clinical and Laboratory Standards Institute broth microdilution method M38-A2. INK128 alone was inactive against all isolates tested. However, favorable synergistic effects between INK128 and voriconazole were observed in 61% Exophiala strains and 60% Fusarium strains, despite Fusarium strains exhibited high MIC values (4-8 μg/ml) against voriconazole. In addition, synergistic effects of INK128/itraconazole were shown in 33% Exophiala strains and 30% Fusarium strains, while synergy of INK128/posaconazole were observed in 28% Exophiala strains and 30% Fusarium strains. The effective working ranges of INK128 were 0.125-2 μg/ml and 1-4 μg/ml against Exophiala isolates and Fusarium isolates, respectively. No synergistic effect was observed when INK128 was combined with amphotericin B. No antagonism was observed in all combinations. In conclusion, INK128 could enhance the in vitro antifungal activity of voriconazole, itraconazole and posaconazole against Exophiala spp. and Fusarium spp., suggesting that azoles, especially voriconazole, combined with TOR kinase inhibitor might provide a potential strategy to

  20. Copper Nanowires as Conductive Ink for Low-Cost Draw-On Electronics.

    Science.gov (United States)

    Jason, Naveen Noah; Shen, Wei; Cheng, Wenlong

    2015-08-05

    This work tackles the complicated problem of clump formation and entanglement of high aspect ratio copper nanowires, due to which a well dispersed solution for use as a true ink for drawable electronics has not been made until now. Through rheology studies even a hard to use material like copper nanowires was tailored to be made into a highly efficient conductive ink with only 2 vol % or 18.28 wt % loading which is far lower than existing nanoparticle based inks. This versatile ink can be applied onto various substrates such as paper, PET, PDMS and latex. By using the ink in a roller ball pen, a bending sensor device was simply drawn on paper, which demonstrated detection of various degrees of convex bending and was highly durable as shown in the 10,000 bending cycling test. A highly sensitive strain sensor which has a maximum gauge factor of 54.38 was also fabricated by simply painting the ink onto latex rubber strip using a paintbrush. Finally a complex conductive pattern depicting the Sydney Opera House was painted on paper to demonstrate the versatility and robustness of the ink. The use of Cu NWs is highly economical in terms of the conductive filler loading in the ink and the cost of copper itself as compared to other metal NPs, CNT, and graphene-based inks. The demonstrated e-ink, devices, and facile device fabrication methods push the field one step closer to truly creating cheap and highly reliable skin like devices "on the fly".

  1. Aging of monolithic zirconia dental prostheses: Protocol for a 5-year prospective clinical study using ex vivo analyses

    OpenAIRE

    Koenig, Vinciane; Wulfman, Claudine P.; Derbanne, Mathieu A.; Dupont, Nathalie M.; Le Goff, Stéphane O.; Tang, Mie-Leng; Seidel, Laurence; Dewael, Thibaut Y.; Vanheusden, Alain J.; Mainjot, Amélie K.

    2016-01-01

    Background: Recent introduction of computer-aided design/computer-aided manufacturing (CAD/CAM) monolithic zirconia dental prostheses raises the issue of material low thermal degradation (LTD), a well-known problem with zirconia hip prostheses. This phenomenon could be accentuated by masticatory mechanical stress. Until now zirconia LTD process has only been studied in vitro. This work introduces an original protocol to evaluate LTD process of monolithic zirconia prostheses in the oral enviro...

  2. Zirconia powders production by precipitation: state-of-art review; Producao de pos de zirconia por precipitacao - revisao do estado da arte

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Ana Paula Almeida de; Torem, Mauricio Leonardo [Pontificia Univ. Catolica do Rio de Janeiro, RJ (Brazil). Dept. de Ciencia dos Materiais e Metalurgia

    1994-12-31

    The important role played by zirconia in advanced ceramics can be attributed to its excellent wear and corrosion resistance and refractory character. The polymorphic nature of zirconia made the controlled addition of stabilizing oxides or the constraining effect of a dense ceramics matrix necessary to maintain high parameters had a significant influence on powder properties and on compacted powder behaviour in sintering. Particle shape and size, purity and crystalline structure were specially influenced by precipitation parameters. Therefore, this work presented a review of the state of the art in zirconia powder production and in the recent research on precipitation of that powder. (author) 15 refs., 5 figs., 2 tabs.

  3. Microtensile bond strength of a resin cement to glass infiltrated zirconia-reinforced ceramic: The effect of surface conditioning

    NARCIS (Netherlands)

    Amaral, R.; Ozcan, M.; Bottino, M.A.; Valandro, L.F.

    2006-01-01

    Objectives. This study evaluated the effect of three surface conditioning methods on the microtensile bond strength of resin cement to a glass-infiltrated zirconia-reinforced alumina-based core ceramic. Methods. Thirty blocks (5 x 5 x 4 mm) of In-Ceram Zirconia ceramics (In-Ceram Zirconia-INC-ZR,

  4. Microtensile bond strength of a resin cement to glass infiltrated zirconia-reinforced ceramic : The effect of surface conditioning

    NARCIS (Netherlands)

    Amaral, R; Ozcan, M; Bottino, MA; Valandro, LF

    Objectives. This study evaluated the effect of three surface conditioning methods on the microtensile bond strength of resin cement to a glass-infiltrated zirconia-reinforced alumina-based core ceramic. Methods. Thirty blocks (5 x 5 x 4 mm) of In-Ceram Zirconia ceramics (In-Ceram Zirconia-INC-ZR,

  5. Absence of Dopant Segregation to the Surface of Scandia and Yttria Co-Stabilized Zirconia

    DEFF Research Database (Denmark)

    Vels Hansen, Karin; Mogensen, Mogens Bjerg

    2012-01-01

    stabilized zirconia. The probable reason for this is that due to its size the Sc3+ ion fits better in the zirconia lattice than Y3+ does. The difference in surface composition may be the explanation for the observed increased tolerance toward sulfur of Ni-ScYSZ compared to Ni-YSZ cermets....

  6. Accelerated ceria–zirconia solubilization by cationic diffusion inversion at low oxygen activity

    DEFF Research Database (Denmark)

    Esposito, Vincenzo; Ni, De Wei; Marani, Debora

    2016-01-01

    Fast elemental diffusion at the Gd-doped ceria/Y-stabilized zirconia interface occurs under reducing conditions at low oxygen activity (pO2 < 10−12 atm) and high temperature (1400 °C). This effect leads to formation of thick ceria–zirconia solid solution reaction layers in the micro-range vs. thi...

  7. Tetragonal zirconia quantum dots in silica matrix prepared by a modified sol-gel protocol

    Science.gov (United States)

    Verma, Surbhi; Rani, Saruchi; Kumar, Sushil

    2018-05-01

    Tetragonal zirconia quantum dots (t-ZrO2 QDs) in silica matrix with different compositions ( x)ZrO2-(100 - x)SiO2 were fabricated by a modified sol-gel protocol. Acetylacetone was added as a chelating agent to zirconium propoxide to avoid precipitation. The powders as well as thin films were given thermal treatment at 650, 875 and 1100 °C for 4 h. The silica matrix remained amorphous after thermal treatment and acted as an inert support for zirconia quantum dots. The tetragonal zirconia embedded in silica matrix transformed into monoclinic form due to thermal treatment ≥ 1100 °C. The stability of tetragonal phase of zirconia is found to enhance with increase in silica content. A homogenous dispersion of t-ZrO2 QDs in silica matrix was indicated by the mapping of Zr, Si and O elements obtained from scanning electron microscope with energy dispersive X-ray analyser. The transmission electron images confirmed the formation of tetragonal zirconia quantum dots embedded in silica. The optical band gap of zirconia QDs (3.65-5.58 eV) was found to increase with increase in zirconia content in silica. The red shift of PL emission has been exhibited with increase in zirconia content in silica.

  8. Zirconia thin film preparation by wet chemical methods at low temperature

    NARCIS (Netherlands)

    Popovici, M.; Graaf, de J.; Verschuuren, M.A.; Graat, P.C.J.; Verheijen, M.A.

    2010-01-01

    In this study the preparation of zirconia thin films with a high refractive index at low temperature is aimed for. Two non-hydrolytic type approaches of wet chemical synthesis are presented. Both by sol–gel and colloid chemistry, highly transmissive, smooth thin films of zirconia cubic and/or

  9. Soft tissue response to zirconia and titanium implant abutments : an in vivo within-subject comparison

    NARCIS (Netherlands)

    van Brakel, Ralph; Meijer, Gert J.; Verhoeven, Jan Willem; Jansen, John; de Putter, Cornelis; Cune, Marco S.

    2012-01-01

    Aim To compare the health of the soft tissues towards zirconia and titanium abutments in man, as observed using histological data. Material and Methods Twenty patients received two mandibular implants with either a zirconia or titanium abutment (split mouth study design, left-right randomization).

  10. Soft tissue response to zirconia and titanium implant abutments: an in vivo within-subject comparison.

    NARCIS (Netherlands)

    Brakel, R. van; Meijer, G.J.; Verhoeven, J.W.; Jansen, J.A.; Putter, C. de; Cune, M.S.

    2012-01-01

    AIM: To compare the health of the soft tissues towards zirconia and titanium abutments in man, as observed using histological data. MATERIAL AND METHODS: Twenty patients received two mandibular implants with either a zirconia or titanium abutment (split mouth study design, left-right randomization).

  11. Zirconia dental implants : a clinical, radiographic, and microbiologic evaluation up to 3 years

    NARCIS (Netherlands)

    Brüll, Felix; van Winkelhoff, Arie Jan; Cune, Marco S.

    2014-01-01

    PURPOSE: To retrospectively evaluate the clinical performance of zirconia endosseous implants. MATERIALS AND METHODS: Partially edentulous patients with adequate bone volume to fit yttria tetragonal zirconia polycrystal (Y-TZP) implants at least 3.5 mm wide and 8.0 mm long were included. Full-mouth

  12. Finite Element Analysis of IPS Empress II Ceramic Bridge Reinforced by Zirconia Bar.

    Science.gov (United States)

    Kermanshah, H; Bitaraf, T; Geramy, A

    2012-01-01

    The aim of this study was to determine the effect of trenched zirconia bar on the von Mises stress distribution of IPS -Empress II core ceramics. The three-dimensional model including a three-unit bridge from the second premolar to the second molar was designed. The model was reinforced with zirconia bar (ZB), zirconia bar with vertical trench (VZB) and zirconia bar with horizontal trench (HZB) (cross sections of these bars were circular). The model without zirconia bar was designed as the control. The bridges were loaded by 200 N and 500 N on the occlusal surface at the middle of the pontic component and von Mises stresses were evaluated along a defined path. IN THE CONNECTOR AREA, VON MISES STRESS IN MPA WERE APPROXIMATELY IDENTICAL IN THE SPECIMENS WITH ZB (AT MOLAR CONNECTOR (MC): 4.75 and at premolar connector (PC): 6.40) and without ZB (MC: 5.50, PC: 6.68), and considerable differences were not recognized. Whereas, Von-Mises stress (MPa) in the specimens with horizontal trenched Zirconia bar (HZB) (MC: 3.91, PC: 2.44) and Vertical trenched Zirconia bar (VZB) (MC: 2.53, PC: 2.56) was decreased considerably. Embeded trenched zirconia bar could reinforce IPS-Empress II at the connector area which is a main failure region in all ceramic fixed partial dentures.

  13. Finite Element Analysis of IPS –Empress II Ceramic Bridge Reinforced by Zirconia Bar

    Directory of Open Access Journals (Sweden)

    Allahyar Geramy

    2012-01-01

    Full Text Available Objective: The aim of this study was to determine the effect of trenched zirconia bar on the von Mises stress distribution of IPS –Empress II core ceramics.Material and Methods: The three-dimensional model including a three-unit bridge from the second premolar to the second molar was designed. The model was reinforced with zirconia bar (ZB, zirconia bar with vertical trench (VZB, and zirconia bar with horizontal trench (HZB (cross sections of these bars were circular. The model without zirconia bar was designed as the control. The bridges were loaded by 200 N and 500 N on the occlusal surface at the middle of the pontic component, and Von-Mises stresses were evaluated along a defined path.Result: In the connector area, VonMises stress in MPa were approximately identical in the specimens with ZB (at molar connector (MC: 4.75, and at premolar connector (PC: 6.40 and without ZB (MC: 5.50, PC: 6.68, and considerable differences were not recognized. Whereas, Von-Mises stress (MPa in the specimens with horizontal trenched Zirconia bar (HZB (MC: 3.91, PC: 2.44 and Vertical trenched Zirconia bar (VZB (MC: 2.53, PC: 2.56 was decreased considerably.Conclusion: Embeded trenched zirconia bar could reinforce IPS-Empress II at the connector area which is a main failure region in all ceramic fixed partial dentures.

  14. Preparation and infrared emission of silica-zirconia-alumina doped with erbium for planar waveguide

    International Nuclear Information System (INIS)

    Thu Huong, T.; Kim Anh, T.; Hoai Nam, M.; Barthou, C.; Strek, W.; Quoc Minh, L.

    2007-01-01

    The sol-gel synthesis of Er 3+ (1-5%) doped silica(83)-zirconia(17) waveguide materials with addition of aluminum (6-20 at%) giving a FWHM ( 4 I 13/2 - 4 I 15/2 )>60 nm is reported. Zirconia with high refractive index of 1.9 and low phonon energy is a good material compared with titania. The films were deposited on silicon or silica substrate by dipcoating technique using the precursors of Si(OC 2 H 5 ) 4 (Aldrich), Zr(C 3 H 7 O) 4 , CH 3 -CH(OH)-CH 3 , C 5 H 8 O 2 , Al(NO 3 ) 3 .9H 2 O, Er(NO 3 ) 3 .5H 2 O and Yb(NO 3 ) 3 .5H 2 O (Merck). The dipcoating rate of 2 and 3 mm/s were controlled by computer. Samples were calcinated at temperatures from 70 to 900 deg. C. The optical properties were studied by photoluminescent spectra and decay time. Influence of the Al 3+ concentration and the heat treatment conditions for the Er 3+ luminescent properties were studied. An energy transfer from 2 F 5/2 (Yb 3+ ) to 4 I 11/2 (Er 3+ ) multiplets is followed by a relaxation to the 4 I 13/2 (Er 3+ ) and an efficiency luminescence of Er 3+ ( 4 I 13/2 - 4 I 15/2 ) was clearly measured. It is interesting to indicate that the lifetime of few ms of Er 3+ at 1530 nm in the sample Si(83)Zr(17)Al(6%)Er(1%)Yb(1%) is longer than for the sample without Yb ions. Multilayer thin films were prepared. The thickness, refractive index, the roughness about 2 nm and a propagation loss<2.5 dB/cm were studied for active planar waveguide applications

  15. Synthesis of Mesoporous Nanocrystalline Zirconia by Surfactant-Assisted Hydrothermal Approach.

    Science.gov (United States)

    Nath, Soumav; Biswas, Ashik; Kour, Prachi P; Sarma, Loka S; Sur, Ujjal Kumar; Ankamwar, Balaprasad G

    2018-08-01

    In this paper, we have reported the chemical synthesis of thermally stable mesoporous nanocrystalline zirconia with high surface area using a surfactant-assisted hydrothermal approach. We have employed different type of surfactants such as CTAB, SDS and Triton X-100 in our synthesis. The synthesized nanocrystalline zirconia multistructures exhibit various morphologies such as rod, mortar-pestle with different particle sizes. We have characterized the zirconia multistructures by X-ray diffraction study, Field emission scanning electron microscopy, Attenuated total refection infrared spectroscopy, UV-Vis spectroscopy and photoluminescence spectroscopy. The thermal stability of as synthesized zirconia multistructures was studied by thermo gravimetric analysis, which shows the high thermal stability of nanocrystalline zirconia around 900 °C temperature.

  16. Effects of multiple firings on the microstructure of zirconia and veneering ceramics.

    Science.gov (United States)

    Alkurt, Murat; Yeşil Duymus, Zeynep; Gundogdu, Mustafa

    2016-01-01

    The aim of study was to evaluate the effects of multiple firings on the microstructures of zirconia and two ceramics. Vita VM9 (VMZ) and Cerabien ZR (C-Z) ceramics on a zirconia framework and zirconia without veneering ceramic (WO-Z) were evaluated. Firing methods included firing two, five, and ten times (n=10). The effects of multiple firings on the surface hardness of the materials were evaluated using a Vickers hardness (HV) tester. Data were analyzed by two-way ANOVA and Tukey's test (α=0.05). After firing five and ten times, the hardness of VM-Z and C-Z increased significantly (p0.05). In the XRD analysis, zirconia had similar tetragonal (t)-monoclinic (m) phase transformations of Y-TZP after the different firing times. Clinically, multiple firings did not affect the microstructure of zirconia, but the structures of the two ceramics were affected.

  17. Characterization of Printing Inks Using DART-Q-TOF-MS and Attenuated Total Reflectance (ATR) FTIR.

    Science.gov (United States)

    Williamson, Rhett; Raeva, Anna; Almirall, Jose R

    2016-05-01

    The rise in improved and widely accessible printing technology has resulted in an interest to develop rapid and minimally destructive chemical analytical techniques that can characterize printing inks for forensic document analysis. Chemical characterization of printing inks allows for both discrimination of inks originating from different sources and the association of inks originating from the same source. Direct analysis in real-time mass spectrometry (DART-MS) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) were used in tandem to analyze four different classes of printing inks: inkjets, toners, offset, and intaglio. A total of 319 samples or ~ 80 samples from each class were analyzed directly on a paper substrate using the two methods. DART-MS was found to characterize the semi-volatile polymeric vehicle components, while ATR-FTIR provided chemical information associated with the bulk components of these inks. Complimentary data results in improved discrimination when both techniques are used in succession resulting in >96% discrimination for all toners, 95% for all inkjets, >92% for all offset, and >54% for all intaglio inks. © 2016 American Academy of Forensic Sciences.

  18. Fourier Transform Infrared (FTIR Spectroscopy with Chemometric Techniques for the Classification of Ballpoint Pen Inks

    Directory of Open Access Journals (Sweden)

    Muhammad Naeim Mohamad Asri

    2015-12-01

    Full Text Available FTIR spectroscopic techniques have been shown to possess good abilities to analyse ballpoint pen inks. These in-situ techniques involve directing light onto ballpoint ink samples to generate an FTIR spectrum, providing “molecular fingerprints” of the ink samples thus allowing comparison by direct visual comparison. In this study, ink from blue (n=15 and red (n=15 ballpoint pens of five different brands: Kilometrico®, G-Soft®, Stabilo®, Pilot® and Faber Castell® was analysed using the FTIR technique with the objective of establishing a distinctive differentiation according to the brand. The resulting spectra were first compared and grouped manually. Due to the similarities in terms of colour and shade of the inks, distinctive differentiation could not be achieved by means of direct visual comparison. However, when the same spectral data was analysed by Principal Component Analysis (PCA software, distinctive grouping of the ballpoint pen inks was achieved. Our results demonstrate that PCA can be used objectively to investigate ballpoint pen inks of similar colour and more importantly of different brands.

  19. Influence of the Substrate Properties on the Offset Printing ink Colour Matching

    Directory of Open Access Journals (Sweden)

    Anne Blayo

    2003-07-01

    Full Text Available The printing industry has been using computerised ink colour matching for a long time. The problem of ink formulation is to match a given standard colour with only three or four inks from a basis of about twelve inks.This is generally achieved by calculations based on the well-known Kubelka-Munk turbid media theory, which gives excellent results in many industrial situations. However, some hypotheses are necessary to apply the Kubelka-Munk model and corrections to the measured reflectance are often required (Saunderson’s correction coefficients, for example.One limitation in the resolution of this method of formulation may arise from the fact that the characterisation of the basic inks is made on one standard substrate, which may differ a lot from the real printing substrate.The aim of this work is precisely to study the contribution of the substrate to the colour matching procedure. The properties of the substrate which intervene in the process are physical properties (thickness, absorbency… and optical properties (brightness and gloss. Five different papers were chosen to make the characterisations of the basic offset inks. The reflectance measurements were performed with spectrophotometer X-Rite with the D/0° geometry, specular excluded or included, coupled with a coloured matching software (X-Rite Inkmaster. A special emphasis was put on the influence on the calculation of the ink film thickness, estimated for the different substrates, and on the choice of the correction coefficients for the Kubelka-Munk theory.

  20. Fast and Simple Forensic Red Pen Ink Analysis Using Ultra-Performance Liquid Chromatography (UPLC)

    International Nuclear Information System (INIS)

    Lee, L.C.; Ying, S.L.; Wan Nur Syazwani Wan Mohamad Fuad; Ab Aziz Ishak; Khairul Osman

    2016-01-01

    Ultra-performance liquid chromatography (UPLC) is more effective than high performance liquid chromatography in terms of analysis speed and sensitivity. This paper presents a feasibility study on forensic red pen inks analysis using UPLC. A total of 12 varieties of red ball point pen inks were purchased from selected stationary shop. For each variety, four different individual pens were sampled to provide intra-variability within a particular variety of pen. The proposed approach is very simple that it only involved limited analysis step and chemicals. A total of 144 chromatograms were obtained from red ink entries extracted with 1.5 mL 80 % (v/v) acetonitrile. Peaks originated from pen inks were determined by comparing the chromatograms of both blank paper and blank solvent against that of ink samples. Subsequently, one-way ANOVA was conducted to discriminate all 66 possible pairs for red pen inks. Results showed that the proposed approach giving discriminating power of 95.45 %. The outcome of the study indicates that UPLC could be a fast and simple approach to red ball point pen inks analysis. (author)

  1. Cosmic Ink: Fragments from the Past on Journal Pages

    Science.gov (United States)

    Mandrino, A.; Gargano, M.; Gasperini, A.

    2015-04-01

    This contribution describes an editorial project started in 2012 to enhance the cultural heritage of the Italian observatories. It includes a regular column Cieli di inchiostro (Cosmic ink) devoted to promoting the astronomical historical archives and published in the Giornale di astronomia, a journal of the Società Astronomica Italiana. In every issue of the journal, a significant historical artifact is presented and described. This can be a letter, a diary page, a photograph, a map, a drawing, or another type of item pulled out of the archival folders to bring its history to light. The column is intended to invite historians, amateurs, and students to search and use the documents kept in the archives of the observatories.

  2. Plasmonic laser printing for ink-free color decoration

    DEFF Research Database (Denmark)

    Zhu, Xiaolong; Vannahme, Christoph; Højlund-Nielsen, Emil

    2016-01-01

    Here we show a method of color printing on nanoimprinted plasmonic metasurfaces [1] using laser post-writing. Laser pulses induce transient local heat generation that leads to melting and reshaping of the imprinted nanostructures [2]. This leads to melting and reshaping of the imprinted 20nm Al...... also be used on a larger scale to personify products such as mobile phones with unique decorations, names, etc‥ This laser technology may create environmentally sound color printing solutions and simplify the production for consumer products....... structures embedded in plastics. Depending on the laser pulse energy density, different surface morphologies that support different plasmonic resonances leading to different color appearances can be created. Color printing by this technology has several advantages over dye technology: ink/toner-free, sub...

  3. Ultrafast Paper Thermometers Based on a Green Sensing Ink.

    Science.gov (United States)

    Tao, Xinglei; Jia, Hanyu; He, Yonglin; Liao, Shenglong; Wang, Yapei

    2017-03-24

    With the use of an ionic liquid as the ultrathermosensitive fluid, a paper thermometer is successfully developed with intrinsic ability of ultrafast response and high stability upon temperature change. The fluidic nature allows the ionic liquid to be easily deposited on paper by pen writing or inkjet printing, affording great promise for large-scale fabrication of low-cost paper sensors. Owing to the advantages of nonvolatilization, excellent continuity and deformability, the thermosensitive ink trapped within the cellulose fibers of paper matrix has no leakage or evaporation at open states, ensuring the excellent stability and repeatability of thermal sensing against arbitrary bending and folding operation. By shortening the heat exchange distance between ionic liquid and samples, it takes only 8 s for the thermometer to reach an electrical equilibrium at a given temperature. Moreover, the paper thermometer can be applied to remotely monitor temperature change with the combination of a wireless communication technology.

  4. Detection and identification of dyes in blue writing inks by LC-DAD-orbitrap MS.

    Science.gov (United States)

    Sun, Qiran; Luo, Yiwen; Yang, Xu; Xiang, Ping; Shen, Min

    2016-04-01

    In the field of forensic questioned document examination, to identify dyes detected in inks not only provides a solid foundation for ink discrimination in forged contents identification, but also facilitates the investigation of ink origin or the study regarding ink dating. To detect and identify potential acid and basic dyes in blue writing inks, a liquid chromatography-diode array detection-Orbitrap mass spectrometry (LC-DAD-Orbitrap MS) method was established. Three sulfonic acid dyes (Acid blue 1, Acid blue 9 and Acid red 52) and six triphenylmethane basic dyes (Ethyl violet, Crystal violet, Methyl violet 2B, Basic blue 7, Victoria blue B and Victoria blue R) were employed as reference dyes for method development. Determination of the nine dyes was validated to evaluate the instrument performance, and it turned out to be sensitive and stable enough for quantification. The method was then applied in the screening analysis of ten blue roller ball pen inks and twenty blue ballpoint pen inks. As a result, including TPR (a de-methylated product of Crystal violet), ten known dyes and four unknown dyes were detected in the inks. The latter were further identified as a de-methylated product of Victoria blue B, Acid blue 104, Acid violet 49 and Acid blue 90, through analyzing their characteristic precursor and product ions acquired by Orbitrap MS with good mass accuracy. The results showed that the established method is capable of detecting and identifying potential dyes in blue writing inks. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. STUDY OF INK LAYER BY METHOD OF ATTENUATED TOTAL REFLECTANCE SPECTROSCOPY

    Directory of Open Access Journals (Sweden)

    D. G. Fatkhullina

    2016-05-01

    Full Text Available Subject of Research. Researchresults of thickness distribution of an ink layer smearedon a glass surface are presented. The orange ink which is used as a coloring pigment in writing instrument (highlighter is selectedasan object of study. Method. Researches were carried out by the method of attenuated total reflectance(ATR spectroscopy. The spectral setup fitted up on the basis of monochromator MDR-204 was usedin the experiment. The peculiarity of the measurement scheme is the applicationofhigh-resolution camera as a radiation detector and information storage as an images package. Researches allowed receivingexperimental data in the form of ink ATR spectra arrayfor studied areas of layer surface in a given spectral range. Main Results. The estimation of ink layer thickness was done, that gives the possibilityto visualize its distribution over the surface using three-dimensional modeling capabilities. The thickness of the ink layer is not more than 0.12 microns and arithmetic mean of the thickness is0.06 microns. The local areas are observed in an ink distribution, they have a maximum layer thickness (0.07-0.12 microns or areas with the ink thickness less then 0.03 microns. Variation of the ink layer thicknessbetween the local areas is smooth. Practical Relevance. The proposed measuring scheme, the sequence of registration and processing of experimental data can be used to studyink distribution within the thickness of a surface layer of other materials,for example, in analysis of signs performed by an ink on paper medium in order to identify them in such areas of science as forensic science andstudy of art.

  6. Black Ink of Activated Carbon Derived From Palm Kernel Cake (PKC)

    Science.gov (United States)

    Selamat, M. H.; Ahmad, A. H.

    2009-06-01

    Recycling the waste from natural plant to produce useful end products will benefit many industries and help preserve the environment. The research reported in this paper is an investigation on the use of the natural waste of palm kernel cake (PKC) to produce carbon residue as a black carbon for pigment source by using pyrolysis process. The activated carbons (AC) is produced in powder form using ball milling process. Rheological spectra in ink is one of quality control process in determining its performance properties. Findings from this study will help expand the scientific knowledge-base for black ink production and formulation base on PKC. Various inks with different weight percentage compositions of AC will be made and tested against its respective rheological properties in order to determine ideal ink printing system. The items in the formulation used comprised of organic and bio-waste materials with added additive to improve the quality of the black ink. Modified Polyurethane was used as binder. The binder's properties highlighted an ideal vehicle to be applied for good black ink opacity performance. The rheological behaviour is a general foundation for ink characterization where the wt% of AC-PKC resulted in different pseudoplastic behaviors, including the Newtonian behavior. The result found that Newtonian field was located in between 2 wt% and 10 wt% of AC-PKC composition with binder. Mass spectroscopy results shown that the carbon content in PKC is high and very suitable for black performance. In the ageing test, the pigment of PKC perform fairly according to the standard pigment of Black carbon (CB) of ferum oxide pigment. The contact angle for substrate's wettability of the ink system shown a good angle proven to be a water resistive coating on paper subtrates; an advantage of the PKC ink pigment performance.

  7. Degradation of inkjet ink by greensand and ultrasonic sonification

    Directory of Open Access Journals (Sweden)

    Mirela Rožić

    2017-07-01

    Full Text Available The study describes the degradation of inkjet ink at low frequency ultrasound (US and greensand to compare their reactivity. Environmental sonochemistry is a rapidly growing area and an example of the advanced oxidation process (AOP that deals with the destruction of organic species in aqueous solutions. Greensand is a granular material coated with a thin layer of manganese dioxide (MnO2 which is among the strongest natural oxidants. In our study magenta inkjet water-based printing ink was dissolved in distilled water and the solutions obtained after degradation were analysed in terms of total organic compound (TOC and absorption curves in the visible spectra. Also used for the process monitoring was high performance liquid chromatography (HPLC. The efficiency of discoloration is significantly affected by the effluent pH. The efficiency of discolouration was higher when the pH of initial solution was 2 with respect to the initial solution pH of 5.5. In all solutions, irrespective of the initial pH value and the processing method the oxidation of polyhydric alcohols occurs. Although the decomposition is significant, surface peaks resulting from HPLC analysis are very small. Decolourization is closely related to the cleavage of the – C=C and -N=N- bonds, and oxidation of polyhydric alcohol to the formation of monosaccharides, carboxylic acids or other low molecular weight compounds with a lesser number of unsaturated double bonds. These compounds have low UV absorbance or they absorb below 200 nm and therefore their detection is impossible. Thus, the obtained total organic compound results indicate a small degree of mineralization. The effectiveness of the low-frequency ultrasound (20 kHz oxidation is similar to the effectiveness of oxidation by greendsand.

  8. Evaluation of participants' perception and taste thresholds with a zirconia palatal plate.

    Science.gov (United States)

    Wada, Takeshi; Takano, Tomofumi; Tasaka, Akinori; Ueda, Takayuki; Sakurai, Kaoru

    2016-10-01

    Zirconia and cobalt-chromium can withstand a similar degree of loading. Therefore, using a zirconia base for removable dentures could allow the thickness of the palatal area to be reduced similarly to metal base dentures. We hypothesized that zirconia palatal plate for removable dentures provides a high level of participants' perception without influencing taste thresholds. The purpose of this study was to evaluate the participants' perception and taste thresholds of zirconia palatal plate. Palatal plates fabricated using acrylic resin, zirconia, and cobalt-chromium alloy were inserted into healthy individuals. Taste thresholds were investigated using the whole-mouth gustatory test, and participants' perception was evaluated using the 100-mm visual analog scale to assess the ease of pronunciation, ease of swallowing, sensation of temperature, metallic taste, sensation of foreign body, subjective sensory about weight, adhesiveness of chewing gum, and general satisfaction. For the taste thresholds, no significant differences were noted in sweet, salty, sour, bitter, or umami tastes among participants wearing no plate, or the resin, zirconia, and metal plates. Speech was easier and foreign body sensation was lower with the zirconia plate than with the resin plate. Evaluation of the adhesiveness of chewing gum showed that chewing gum does not readily adhere to the zirconia plate in comparison with the metal plate. The comprehensive participants' perception of the zirconia plate was evaluated as being superior to the resin plate. A zirconia palatal plate provides a high level of participants' perception without influencing taste thresholds. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  9. Sol–gel zirconia nanopowders with α-cyclodextrin as organic additive

    International Nuclear Information System (INIS)

    Răileanu, M.; Todan, L.; Crişan, D.; Drăgan, N.; Crişan, M.; Stan, C.; Andronescu, C.; Voicescu, M.; Vasile, B.S.; Ianculescu, A.

    2012-01-01

    Highlights: ► The sol–gel synthesis of a zirconia powder has been performed, in the presence of α-cyclodextrin as organic additive. ► A crystalline powder consisting from a mixture of monoclinic and tetragonal zirconia phases has resulted after the thermal treatment. ► The organic additive acted the role of metal oxides used as doppants for zirconia powders, avoiding phase transformations. ► The α-cyclodextrin made particles to assume spherical shape and reach fairly uniform size and prevented their agglomeration. ► The organic additive led to a certain porous morphology of the zirconia particles that is pores embedded within grains. - Abstract: Nanomaterials present unique structural and physicochemical properties due to their ultra fine size of particles that make them very useful in many domains. The most spectacular applications of nanosized zirconia include ceramics, piezoelectrics, refractories, pigments, solid electrolytes, oxygen sensors, catalysts, ultrafiltration membranes, and chromatography packing materials. Nanostructured zirconia powders can be prepared using various methods, such as sol–gel process, coprecipitation, hydrothermal synthesis, and reverse micelle method. The aim of the present work was to prepare zirconia nanopowders through the sol–gel method, using α-cyclodextrin as organic additive and to establish its influence on the structural and textural properties of the obtained product. A white, amorphous ZrO 2 powder containing α-cyclodextrin was prepared, which became a crystalline, stable one, after removing the organic matter by thermal treatment. The resulted nanocrystalline powder contains both monoclinic and tetragonal zirconia phases and is very stable. It presents a relatively reduced tendency of agglomeration of particles and contains closed pores which are embedded in the zirconia matrix. The zirconia powders were characterized using the following methods: thermal analysis, IR spectroscopy, UV–vis spectroscopy

  10. Shear bond strength between an indirect composite layering material and feldspathic porcelain-coated zirconia ceramics.

    Science.gov (United States)

    Fushiki, Ryosuke; Komine, Futoshi; Blatz, Markus B; Koizuka, Mai; Taguchi, Kohei; Matsumura, Hideo

    2012-10-01

    This study aims to evaluate the effect of both feldspathic porcelain coating of zirconia frameworks and priming agents on shear bond strength between an indirect composite material and zirconia frameworks. A total of 462 airborne-particle-abraded zirconia disks were divided into three groups: untreated disks (ZR-AB), airborne-particle-abraded zirconia disks coated with feldspathic porcelain, (ZR-PO-AB), and hydrofluoric acid-etched zirconia disks coated with feldspathic porcelain (ZR-PO-HF). Indirect composite (Estenia C&B) was bonded to zirconia specimens with no (CON) or one of four priming agents--Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB + activator), Estenia Opaque primer, or Porcelain Liner M Liquid B (PLB)--with or without an opaque material (Estenia C&B Opaque). All specimens were tested for shear bond strength before and after 20,000 thermocycles. The Steel-Dwass test and Mann-Whitney U test were used to compare shear bond strength. In ZR-AB specimens, the initial bond strength of the CPB and CPB + Activator groups was significantly higher as compared with the other three groups (P material, bond strength was significantly lower in ZR-AB specimens than in ZR-PO-AB and ZR-PO-HF specimens (P composite to zirconia independent of surface treatment. The use of a silane coupling agent and opaque material yields durable bond strength between the indirect composite and feldspathic-porcelain-coated zirconia. The results of the present study suggest that feldspathic porcelain coating of zirconia frameworks is an effective method to obtain clinically acceptable bond strengths of a layering indirect composite material to a zirconia framework.

  11. Bond strength and Raman analysis of the zirconia-feldspathic porcelain interface.

    Science.gov (United States)

    Ramos, Carla Müller; Cesar, Paulo Francisco; Lia Mondelli, Rafael Francisco; Tabata, Americo Sheitiro; de Souza Santos, Juliete; Sanches Borges, Ana Flávia

    2014-10-01

    Zirconia has the best mechanical properties of the available ceramic systems. However, the stability of the zirconia-feldspathic porcelain interface may be jeopardized by the presence of the chipping and debonding of the feldspathic porcelain. The purpose of this study is to evaluate the shear bond strength of 3 cold isostatic pressed zirconia materials and a feldspathic veneer by analyzing their interface with micro-Raman spectroscopy. The test groups were experimental zirconia, Zirkonzahn zirconia, and Schuetz zirconia. Blocks of partially sintered zirconia were cut into disks (n=20) and then veneered with a feldspathic porcelain. Half of the specimens from each group (n=10) were incubated in 37°C water for 24 hours, and the other half were thermocycled. All the specimens were then subjected to shear testing. The fractured areas were analyzed with optical stereomicroscopy and classified as adhesive, cohesive, or an adhesive-cohesive failure. Spectral patterns were examined to detect bands related to the zirconia and feldspathic porcelain phases. The shear strength data were submitted to 2-way ANOVA. No significant differences in shear bond strength were observed among the 3 groups, regardless of whether or not the specimens were thermocycled. Adhesive failures were the most prevalent types of failure (70%). Raman spectra were clearly distinguished for all the materials, which showed the presence of tetragonal and monoclinic phases. The controlled production of the experimental zirconia did not influence the results of the bond strength. Raman analysis suggested a process of interdiffusion by the presence of peaks associated with the zirconia and feldspathic ceramics. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  12. Effectiveness of India ink as a long-term colonic mucosal marker.

    Science.gov (United States)

    Fennerty, M B; Sampliner, R E; Hixson, L J; Garewal, H S

    1992-01-01

    We prospectively studied the use of India ink as a long-term or "permanent" mucosal marker as part of a study investigating the natural history of diminutive distal colorectal polyps. Twenty-six patients had 32 India ink tatoos implanted. The tatoo sites of the 19 patients who were followed at least 6 months continued to display intensely stained mucosa at the original sites. No side effects or complications were encountered. India ink appears to be a safe and effective long-term marker for colonic mucosal lesions.

  13. Low-Temperature Processed Ga-Doped ZnO Coatings from Colloidal Inks

    KAUST Repository

    Della Gaspera, Enrico

    2013-03-06

    We present a new colloidal synthesis of gallium-doped zinc oxide nanocrystals that are transparent in the visible and absorb in the near-infrared. Thermal decomposition of zinc stearate and gallium nitrate after hot injection of the precursors in a mixture of organic amines leads to nanocrystals with tunable properties according to gallium amount. Substitutional Ga3+ ions trigger a plasmonic resonance in the infrared region resulting from an increase in the free electrons concentration. These nanocrystals can be deposited by spin coating, drop casting, and spray coating resulting in homogeneous and high-quality thin films. The optical transmission of the Ga-ZnO nanoparticle assemblies in the visible is greater than 90%, and at the same time, the near-infrared absorption of the nanocrystals is maintained in the films as well. Several strategies to improve the films electrical and optical properties have been presented, such as UV treatments to remove the organic compounds responsible for the observed interparticle resistance and reducing atmosphere treatments on both colloidal solutions and thin films to increase the free carriers concentration, enhancing electrical conductivity and infrared absorption. The electrical resistance of the nanoparticle assemblies is about 30 kΩ/sq for the as-deposited, UV-exposed films, and it drops down to 300 Ω/sq after annealing in forming gas at 450 °C, comparable with state of the art tin-doped indium oxide coatings deposited from nanocrystal inks. © 2013 American Chemical Society.

  14. Microstructure-electrical properties relation of zirconia based ceramic composites

    International Nuclear Information System (INIS)

    Fonseca, Fabio Coral

    2001-01-01

    The electrical properties of zirconia based ceramic composites were studied by impedance spectroscopy. Three materials were prepared with different relative compositions of the conducting and insulating phases: (ZrO 2 :8 mol% Y 2 ) 3 ) + MgO, (ZrO 2 :8 mol% Y 2 O 3 ) + Y 2 O 3 and ZrO 2 + 8 mol% Y 2 O 3 . All specimens were analyzed by X-ray diffraction and scanning electron microscopy for microstructural characterization and for correlation of microstructural aspects with electrical properties. For (ZrO 2 :8 mol% Y 2 O 3 ) + MgO the main results show that the dependence of the different (microstructural constituents) contributions to the electrical resistivity on the magnesia content follows two stages: one below and another above the solubility limit of magnesia in Yttria-stabilized zirconia. The same dependence is found for the lattice parameter determined by X-ray diffraction measurements. The impedance diagrams of the composites have been resolved allowing the identification of contributions due to the presence of each microstructural constituent in both stages. Magnesia as a second phase is found to inhibit grain growth in Yttria-stabilized zirconia and the solubility limit for magnesia in the zirconia matrix is around 10 mol%. For (ZrO 2 :8 mol% Y 2 O 3 ) + Y 2 O 3 the main results show that: Yttria is present as a second phase for 1350 deg C /0.1 h sintering; the addition of 2 mol% of Yttria does not modify significantly the electrical properties; the solubility limit for Yttria is around 2 mol% according to electrical measurements. Similarly to magnesia, Yttria inhibits grain growth on Yttria-stabilized zirconia. The general effective medium theory was used to analyze the percolation of the insulating phase; the percolation threshold is different if one considers separately the total, bulk and grain boundary contributions to the electrical conductivity: 32.0, 38.5 and 27.8 vol% for total, intra and intergranular contributions, respectively. The increase of

  15. Fracture Resistance of Zirconia Restorations with a Modified Framework Design

    Directory of Open Access Journals (Sweden)

    sakineh Nikzadjamnani

    2017-12-01

    Full Text Available Objectives: Chipping is one of the concerns related to zirconia crowns. The reasons of chipping have not been completely understood. This in-vitro study aimed to assess the effect of coping design on the fracture resistance of all-ceramic single crowns with zirconia frameworks. Materials and Methods: Two types of zirconia copings were designed (n=12: (1 a standard coping (SC with a 0.5mm uniform thickness and (2 a modified coping (MC consisted of a lingual margin of 1mm thickness and 2mm height connected to a proximal strut of 4mm height and a 0.3mm-wide facial collar. After veneer porcelain firing, the crowns were cemented to metal dies. Afterwards, a static vertical load was applied until failure. The modes of failure were determined. Data were calculated and statistically analyzed by independent samples T-test. P<0.05 was considered statistically significant.Results: The mean and standard deviation (SD of the final fracture resistance equaled to 3519.42±1154.96 N and 3570.01±1224.33 N in SC and MC groups, respectively; the difference was not statistically significant (P=0.9. Also, the mean and SD of the initial fracture resistance equaled to 3345.34±1190.93 N and 3471.52±1228.93 N in SC and MC groups, respectively (P=0.8. Most of the specimens in both groups showed the mixed failure mode. Conclusions: Based on the results, the modified core design may not significantly improve the fracture resistance.

  16. A study of the structure and crystallisation of nanocrystalline zirconia

    International Nuclear Information System (INIS)

    Tucker, M.

    1999-12-01

    Nanocrystalline zirconia, prepared via, calcination of the hydroxide, has been studied using a variety of experimental techniques. Two chemical routes, a precipitation and a sol-gel route, were used to prepare the hydroxide. Neutron and X-ray diffraction, EXAFS, NMR and SANS have been used to study the structure and crystallisation, during in-situ and ambient condition measurements. The structural information from the diffraction data has been complimented by the other techniques to provide information on the short, medium and longer range structure of nanocrystalline zirconia. Pure and yttrium doped samples were studied, this enabled the affects of doping and preparation routes to be investigated. The amorphous hydroxide was found to have a, monoclinic-like structure for all samples, independent of preparation route or yttrium content. The crystallisation temperature was lowest for the pure precipitation sample and was increased by the addition of yttrium or by preparation via, the sol-gel route. For the precipitation samples, in addition to the crystallisation temperature being raised, doping with yttrium also had an effect on the size of the crystallites obtained at high temperatures. Due to the different incorporation method of the yttrium into the sol-gel samples the effect on crystallite size and crystallisation temperature, as seen for the precipitation samples, were not evident for the sol-gel samples. The neutron and NMR data clearly show hydrogen remains in the samples well after crystallisation has become evident. The structural picture of nanocrystalline zirconia consisting of small crystallites surrounded by material containing, or terminated by, hydroxyl groups, is supported by all the results and methods used in this thesis. The in-situ and ambient conditions data is combined into a coherent growth picture of the nanocrystalline material from the hydroxide until at high enough temperatures the bulk or polycrystalline material is formed. (author)

  17. Biomolecular modification of zirconia surfaces for enhanced biocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Shih-Kuang; Hsu, Hsueh-Chuan [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan, ROC (China); Ho, Wen-Fu [Department of Chemical and Materials Engineering, National University of Kaohsiung, Taiwan, ROC (China); Yao, Chun-Hsu [Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung 40402, Taiwan, ROC (China); Chang, Pai-Ling [Taoyuan General Hospital, Taoyuan 33004, Taiwan, ROC (China); Wu, Shih-Ching, E-mail: scwu@ctust.edu.tw [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan, ROC (China)

    2014-12-01

    Yttria-tetragonal zirconia polycrystal (Y-TZP) is a preferred biomaterial due to its good mechanical properties. In order to improve the biocompatibility of zirconia, RGD-peptide derived from extracellular matrix proteins was employed to modify the surface of Y-TZP to promote cell adhesion in this study. The surface of Y-TZP specimens was first modified using a hydrothermal method for different lengths of time. The topographies of modified Y-TZP specimens were analyzed by contact angle, XRD, FTIR, AFM, and FE-SEM. The mechanical properties were evaluated using Vickers hardness and three point bending strength. Then, the RGD-peptide was immobilized on the surface of the Y-TZP by chemical treatment. These RGD-peptide immobilized Y-TZP specimens were characterized by FTIR and AFM, and then were cocultured with MG-63 osteoblast cells for biocompatibility assay. The cell morphology and proliferation were evaluated by SEM, WST-1, and ALP activity assay. The XRD results indicated that the phase transition, from tetragonal phase to monoclinic phase, was increased with a longer incubation time of hydrothermal treatment. However, there were no significant differences in mechanical strengths after RGD-peptide was successfully grafted onto the Y-TZP surface. The SEM images showed that the MG-63 cells appeared polygonal, spindle-shaped, and attached on the RGD-peptide immobilized Y-TZP. The proliferation and cellular activities of MG-63 cells on the RGD-peptide immobilized Y-TZP were better than that on the unmodified Y-TZP. From the above results, the RGD-peptide can be successfully grafted onto the hydrothermal modified Y-TZP surface. The RGD-peptide immobilized Y-TZP can increase cell adhesion, and thus, improve the biocompatibility of Y-TZP. - Highlights: • Covalent bonding between peptide and Y-TZP was proposed. • Stable biomimetic structures produced on the surface of zirconia. • The biocompatibility was improved.

  18. A novel, disposable, screen-printed amperometric biosensor for glucose in serum fabricated using a water-based carbon ink.

    Science.gov (United States)

    Crouch, Eric; Cowell, David C; Hoskins, Stephen; Pittson, Robin W; Hart, John P

    2005-11-15

    Screen-printed amperometric glucose biosensors have been fabricated using a water-based carbon ink. The enzyme glucose oxidase (GOD) and the electro-catalyst cobalt phthalocyanine were mixed with the carbon ink prior to the screen-printing process; therefore, biosensors are prepared in a one-step fabrication procedure. Optimisation of the biosensor performance was achieved by studying the effects of pH, buffer strength, and applied potential on the analytical response. Calibration studies were performed under optimum conditions, using amperometry in stirred solution, with an operating potential of +500 mV versus SCE. The sensitivity was found to be 1170 nA mM(-1), with a linear range of 0.025-2 mM; the former represents the detection limit. The disposable amperometric biosensor was evaluated by carrying out replicate determinations on a sample of bovine serum. This was achieved by the method of multiple standard additions and included a correction for background currents arising from oxidizable serum components. The mean serum concentration was calculated to be 8.63 mM and compared well with the supplier's value of 8.3 mM; the coefficient of variation was calculated to be 3.3% (n=6).

  19. Microscopic mechanism of stability in yttria-doped zirconia

    CERN Document Server

    Ostanin, S A

    2001-01-01

    The relaxed configurations of yttria-stabilized zirconia (YSZ) between 3 and 10 mol. % Y sub 2 O sub 3 were modeled within the pseudopotential technique. The vibration mode corresponding to the soft phonon in pure c-ZrO sub 2 has been calculated for each Y sub 2 O sub 3 composition. These anharmonic vibrations, associated with stabilization of YSZ, have been investigated within the self-consistent phonon approximation that makes obtainable the fine structure in spectral density. In studying the phonon dynamics, it is proposed to use the displacement probability density which can quantify very accurately the transition temperature needed to stabilize the YSZ cubic phase

  20. Crystalline mesoporous zirconia catalysts having stable tetragonal pore wall structure

    Science.gov (United States)

    Sachtler, W.M.H.; Huang, Y.Y.

    1998-07-28

    Methods are disclosed for the preparation of new sulfated mesoporous zirconia materials/catalysts with crystalline pore walls of predominantly tetragonal crystal structure, characterized by nitrogen physical sorption measurement, X-ray diffraction, transmission electron microscopy and catalytic tests using n-butane isomerization to iso-butane and alkylation of 1-naphthol with 4-tert-butylstyrene as probe reactions. Sulfate deposition is preferred for the transformation of a mesoporous precursor with amorphous pore walls into a material with crystalline pore walls maintaining the mesoporous characteristics. 17 figs.

  1. Microwave sintering of zirconia toughened alumina at 28GHz

    International Nuclear Information System (INIS)

    Samandi, M.; Ji, H.; Miyake, S.

    1998-01-01

    Microwave radiation from a 10 kW, CW gyrotron operating at 28 GHz was employed to sinter 10% zirconia toughened alumina (ZTA) ceramic samples. It has been established that the use of millimetre wave radiation circumvents the difficulties encountered during the sintering of ceramics, i e. formation of hot spot, by radiation at industrially permissible frequency of 2.45GHz. Further, careful density measurement and microstructural characterisation of mm- wave and conventionally sintered samples by XRD, SEM and TEM has unequivocally demonstrated the effectiveness of mm-wave radiation for obtaining high density ceramics at lower sintering temperatures. Copyright (1998) Australasian Ceramic Society

  2. Superplasticity and joining of zirconia-based ceramics

    International Nuclear Information System (INIS)

    Dominguez-Rodriguez, A.; Gutierrez-Mora, F.; Jimenez-Melendo, M.; Chaim, R.; Routbort, J. L.

    1999-01-01

    Steady-state creep and joining of alumina/zirconia composites containing alumina volume fractions of 20, 60, and 85% have been investigated between 1,250 and 1,350 C. Superplasticity of these compounds is controlled by grain-boundary sliding and the creep rate is a function of alumina volume fraction, not grain size. Using the principles of superplasticity, pieces of the composite have been joined by applying the stress required to achieve 5 to 10% strain to form a strong interface at temperatures as low as 1,200 C

  3. Microstructure and durability of zirconia thermal barrier coatings

    International Nuclear Information System (INIS)

    Suhr, D.S.; Mitchell, T.E.; Keller, R.J.

    1983-01-01

    Various combinations of plasma-sprayed bond coatings and zirconia ceramic coatings on a nickel-based superalloy substrate were tested by static thermal exposure at 1200 0 C and cyclic thermal exposure to 1000 0 C. The bond coats were based on Ni-Cr-Al alloys with additions of rare earth elements and Si. The ceramic coats were various ZrO 2 -Y 2 O 3 compositions, of which the optimum was found to be ZrO 2 -8.9 wt% Y 2 O 3 . Microstructural analysis showed that resistance to cracking during thermal exposure is strongly related to deleterious phase changes

  4. Thermal diffusivity of alumina-zirconia sintered with niobium additions

    International Nuclear Information System (INIS)

    Santos, W.N. dos; Paulin Filho, P.I.; Taylor, R.

    1994-01-01

    The effect of niobium oxide addition on the alumina-zirconia thermal diffusivity was investigated from 100 0 C to 1000 0 C by the laser flash method. It was observed that 4 to 6% addition of niobium oxide increases the thermal diffusivity when samples were sintered at 1450 0 C. This effect was due to elimination of porosity by formation of liquid please above 1420 0 C in the Al 2 O 3 - Nb 2 O 5 system. (author). 7 refs., 3 figs

  5. Stability of yttria-stabilized zirconia during pyroprocessing tests

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Eun-Young, E-mail: eychoi@kaeri.re.kr; Lee, Jeong; Lee, Sung-Jai; Kim, Sung-Wook; Jeon, Sang-Chae; Cho, Soo Haeng; Oh, Seung Chul; Jeon, Min Ku; Lee, Sang Kwon; Kang, Hyun Woo; Hur, Jin-Mok

    2016-07-15

    In this study, the feasibility of yttria-stabilized zirconia (YSZ) was investigated for use as a ceramic material, which can be commonly used for both electrolytic reduction and electrorefining. First, the stability of YSZ in salts for electrolytic reduction and electrorefining was examined. Then, its stability was demonstrated by a series of pyroprocessing tests, such as electrolytic reduction, LiCl distillation, electrorefining, and LiCl−KCl distillation, using a single stainless steel wire mesh basket containing fuel and YSZ. A single basket was used by its transportation from one test to subsequent tests without the requirements for unloading.

  6. Synthesis and characterization of MCM-41-supported nano zirconia catalysts

    Directory of Open Access Journals (Sweden)

    Mohamed S. Abdel Salam

    2015-03-01

    Full Text Available Series of MCM-41 supported sulfated Zirconia (SZ catalysts with different loadings (2.5–7.5% wt. were prepared using direct impregnation method. The acquired solid catalysts were characterized structurally and chemically using X-RD, HRTEM, BET, FT-IR, Raman spectroscopy and TPD analysis. The acidity of the solid catalysts was investigated through cumene cracking and isopropanol dehydration at different temperatures. As the SZ loading increases, the surface acidity of the mesoporous catalysts was enhanced, this was reflected by the higher catalytic activity toward cumene cracking and isopropanol dehydration.

  7. Ceramics in engines - Long term stability of transformation toughened zirconia

    International Nuclear Information System (INIS)

    Marmach, M.; Swain, M.V.

    1985-01-01

    The long term thermal stability of two types of magnesia partially stabilized zirconia at temperatures below 1000 0 C has been determined. The effect on mechanical properties and phase stability of isothermal heating at 800 0 C and 900 0 C for up to 2000 hours, and with thermal cycling for a similar period between R.T. and 800 0 C in air, was measured. it was found that peak-aged (MS) type Mg-PSZ was much more stable than the thermal shock resistant (TS) type in both tests and showed minimal degradation

  8. Aqueous-Phase Acetic Acid Ketonization over Monoclinic Zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Qiuxia [Institute for Integrated Catalysis, Pacific Northwest; College; Lopez-Ruiz, Juan A. [Institute for Integrated Catalysis, Pacific Northwest; Cooper, Alan R. [Institute for Integrated Catalysis, Pacific Northwest; Wang, Jian-guo [College; Albrecht, Karl O. [Institute for Integrated Catalysis, Pacific Northwest; Mei, Donghai [Institute for Integrated Catalysis, Pacific Northwest

    2017-12-13

    The effect of aqueous phase on the acetic acid ketonization over monoclinic zirconia has been investigated using first-principles based density functional theory (DFT) calculations. To capture the aqueous phase chemistry over the solid zirconia catalyst surface, the aqueous phase is represented by 111 explicit water molecules with a liquid water density of 0.93 g/cm3 and the monoclinic zirconia is modeled by the most stable surface structure . The dynamic nature of aqueous phase/ interface was studied using ab initio molecular dynamics simulation, indicating that nearly half of the surface Zr sites are occupied by either adsorbed water molecules or hydroxyl groups at 550 K. DFT calculations show that the adsorption process of acetic acid from the liquid water phase to the surface is nearly thermodynamically neutral with a Gibbs free energy of -2.3 kJ/mol although the adsorption strength of acetic acid on the surface in aqueous phase is much stronger than in vapor phase. Therefore it is expected that the adsorption of acetic acid will dramatically affects aqueous phase ketonization reactivity over the monoclinic zirconia catalyst. Using the same ketonization mechanism via the β-keto acid intermediate, we have compared acetic acid ketonization to acetone in both vapor and aqueous phases. Our DFT calculation results show although the rate-determining step of the β-keto acid formation via the C-C coupling is not pronouncedly affected, the presence of liquid water molecules will dramatically affect dehydrogenation and hydrogenation steps via proton transfer mechanism. This work was financially supported by the United States Department of Energy (DOE)’s Bioenergy Technologies Office (BETO) and performed at the Pacific Northwest National Laboratory (PNNL). PNNL is a multi-program national laboratory operated for DOE by Battelle Memorial Institute. Computing time and advanced catalyst characterization use was granted by a user proposal at the William R. Wiley

  9. Superplasticity and joining of zirconia-based ceramics

    International Nuclear Information System (INIS)

    Gutierrez-Mora, F.; Dominguez-Rodriguez, A.; Jimenez-Melendo, M.; Chaim, R.; Ravi, G.B.; Routbort, J.L.

    2000-01-01

    Steady-state creep and joining of alumina/zirconia composites containing alumina volume fractions of 20, 60 and 85% have been investigated between 1,250 and 1,350 C. Superplasticity of these compounds is controlled by grain-boundary sliding and the creep rate is a function of alumina volume fraction, not grain size. Using the principles of superplasticity, pieces of the composite have been joined by applying the stress required to achieve 5 to 10% strain to form a strong interface at temperatures as low as 1,200 C

  10. Ab initio investigation of ground-states and ionic motion in particular in zirconia-based solid-oxide electrolytes

    International Nuclear Information System (INIS)

    Hirschfeld, Julian Arndt

    2012-01-01

    transport the ionic conductivity in SOFC electrolytes is required to be high. Using a layering of zirconium and yttrium in the fluorite structure and applying DFT and NEB again, a high vacancy concentration and a very low migration barrier in two dimensions is observed, while the mobility in the third direction is sacrificed. The ionic conductivity of this new structure at 500 C surpasses that of the state of the art electrolyte Yttrium Stabilized Zirconia (YSZ) at 800 C. Throughout the process of searching for augmented ionic conductivity, the NEB method has particularly been used extensively and has been examined in detail. This method has been applied to quite different systems to gain a better understanding of it. While NEB has been applied, it has been found that a certain modification of the NEB, the Minimum search Nudged Elastic Band (MsNEB), is able to find global minima in a complex phase space. Furthermore, the MsNEB turns out to be complementary to simulated annealing and the genetic algorithm. This new scheme has not been applied to electrolyte materials, yet. However, its capabilities have been demonstrated by detecting the most stable isomers of the phosphorus P 4 , P 8 molecules and the corresponding molecules of As n , Sb n , Bi n , (n=4,8). In the case of P 8 , the new MsNEB has led to a hitherto unknown configuration, being more stable than the previously assumed ground state.

  11. Ab initio investigation of ground-states and ionic motion in particular in zirconia-based solid-oxide electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Hirschfeld, Julian Arndt

    2012-12-11

    transport the ionic conductivity in SOFC electrolytes is required to be high. Using a layering of zirconium and yttrium in the fluorite structure and applying DFT and NEB again, a high vacancy concentration and a very low migration barrier in two dimensions is observed, while the mobility in the third direction is sacrificed. The ionic conductivity of this new structure at 500 C surpasses that of the state of the art electrolyte Yttrium Stabilized Zirconia (YSZ) at 800 C. Throughout the process of searching for augmented ionic conductivity, the NEB method has particularly been used extensively and has been examined in detail. This method has been applied to quite different systems to gain a better understanding of it. While NEB has been applied, it has been found that a certain modification of the NEB, the Minimum search Nudged Elastic Band (MsNEB), is able to find global minima in a complex phase space. Furthermore, the MsNEB turns out to be complementary to simulated annealing and the genetic algorithm. This new scheme has not been applied to electrolyte materials, yet. However, its capabilities have been demonstrated by detecting the most stable isomers of the phosphorus P{sub 4}, P{sub 8} molecules and the corresponding molecules of As{sub n}, Sb{sub n}, Bi{sub n}, (n=4,8). In the case of P{sub 8}, the new MsNEB has led to a hitherto unknown configuration, being more stable than the previously assumed ground state.

  12. Zirconium oxide obtainment from brazilian zircon concentrate

    International Nuclear Information System (INIS)

    Ribeiro, S.; Martins, A.H.

    1991-01-01

    This work presents the experimental results of studies about alkaline melting, acid leaching and sulfation steps for obtention of zirconium oxide and partially stabilized zirconia by yttrium and rare-earth coprecipitation in chlorine medium, starting from the brazilian zircon concentrate. Using statistical methods of factorial design and the Packett-Burman approach, the results are discussed and the optimal conditions of the production steps were determined. (author)

  13. Oral intake of zirconia nanoparticle alters neuronal development and behaviour of Drosophila melanogaster

    Science.gov (United States)

    Mishra, Monalisa; Sabat, Debabrat; Ekka, Basanti; Sahu, Swetapadma; P, Unnikannan; Dash, Priyabrat

    2017-08-01

    Zirconia nanoparticles (ZrO2 NPs) have been extensively used in teeth and bone implants and thus get a chance to interact with the physiological system. The current study investigated the oral administration of various concentrations of ZrO2 NPs synthesized by the hydrothermal method (0.25 to 5.0 mg L-1) on Drosophila physiology and behaviour. The size of the currently studied nanoparticle varies from 10 to 12 nm. ZrO2 NPs accumulated within the gut in a concentration-dependent manner and generate reactive oxygen species (ROS) only at 2.5 and 5.0 mg L-1 concentrations. ROS was detected by nitroblue tetrazolium (NBT) assay and 2',7'-dichlorofluorescein http://www.ncbi.nlm.nih.gov/pubmed/20370560 (H2DCF) staining. The ROS toxicity alters the larval gut structure as revealed by DAPI staining. The NP stress of larvae affects the Drosophila development by distressing pupa count and varying the phenotypic changes in sensory organs (eye, thorax bristle, wings). Besides phenotypic changes, flawed climbing behaviour against gravity was seen in ZrO2 NP-treated flies. All together, for the first time, we have reported that a ROS-mediated ZrO2 NP toxicity alters neuronal development and functioning using Drosophila as a model organism. [Figure not available: see fulltext.

  14. Bulk and Interface Thermodynamics of Calcia-, and Yttria-doped Zirconia Ceramics: Nanograined Phase Stability

    Science.gov (United States)

    Drazin, John Walter

    Calcia-, and yttria- doped zirconia powders and samples are essential systems in academia and industry due to their observed bulk polymorphism. Pure zirconia manifests as Baddeleyite, a monoclinic structured mineral with 7-fold coordination. This bulk form of zirconia has little application due to its asymmetry. Therefore dopants are added to the grain in-order to induce phase transitions to either a tetragonal or cubic polymorph with the incorporation of oxygen vacancies due to the dopant charge mis-match with the zirconia matrix. The cubic polymorph has cubic symmetry such that these samples see applications in solid oxide fuel cells (SOFCs) due to the high oxygen vacancy concentrations and high ionic mobility at elevated temperatures. The tetragonal polymorph has slight asymmetry in the c-axis compared to the a-axis such that the tetragonal samples have increased fracture toughness due to an impact induced phase transformation to a cubic structure. These ceramic systems have been extensively studied in academia and used in various industries, but with the advent of nanotechnology one can wonder whether smaller grain samples will see improved characteristics similar to their bulk grain counterparts. However, there is a lack of data and knowledge of these systems in the nano grained region which provides us with an opportunity to advance the theory in these systems. The polymorphism seen in the bulk grains samples is also seen in the nano-grained samples, but at slightly distinct dopant concentrations. The current theory hypothesizes that a surface excess, gamma (J/m 2), can be added to the Gibbs Free energy equation to account for the additional free energy of the nano-grain atoms. However, these surface energies have been difficult to measure and therefore thermodynamic data on these nano-grained samples have been sparse. Therefore, in this work, I will use a well established water adsorption microcalorimetry apparatus to measure the water coverage isotherms

  15. Characteristics of indium-tin-oxide (ITO) nanoparticle ink-coated layers recycled from ITO scraps

    Science.gov (United States)

    Cha, Seung-Jae; Hong, Sung-Jei; Lee, Jae Yong

    2015-09-01

    This study investigates the characteristics of an indium-tin-oxide (ITO) ink layer that includes nanoparticles synthesized from ITO target scraps. The particle size of the ITO nanoparticle was less than 15 nm, and the crystal structure was cubic with a (222) preferred orientation. Also, the composition ratio of In to Sn was 92.7 to 7.3 in weight. The ITO nanoparticles were well dispersed in the ink solvent to formulate a 20-wt% ITO nanoparticle ink. Furthermore, the ITO nanoparticle ink was coated onto a glass substrate, followed by heat-treatment at 600 °C. The layer showed good sheet resistances below 400 Ω/□ and optical transmittances higher than 88% at 550 nm. Thus, we can conclude that the characteristics of the layer make it highly applicable to a transparent conductive electrode.

  16. Methodology and technological aspects of the flexible substrate preparation for ink-jet printing technology

    Science.gov (United States)

    Tarapata, Grzegorz; Marzecki, Michał

    2013-10-01

    The ink-jet printing technology becomes especially promising for wide volume of production of cheap sensors, consumable electronics and other dedicated applications of everyday life like smart packaging, smart textiles, smart labels, etc. To achieve this goal new materials compatible with ink-jet printing should be developed. Currently on the market there is a growing number of inks with different properties, but their use requires many tests related to its printability and their interaction with other materials. The paper presents technological problems that are encountered by people associated with fabrication of various devices with using of inkjet printing techniques. Results presented in the paper show the influence of surface preparation techniques on the quality of achieved shapes, the impact of other materials already deposited and the impact of another external factors. During carried out experiments the printer Dimatix DMP 2831 and several inks base on nanosilver or dielectric UV curable was used.

  17. Colored inks analysis and differentiation: A first step in artistic contemporary prints discrimination

    International Nuclear Information System (INIS)

    Vila, Anna; Ferrer, Nuria; Garcia, Jose F.

    2007-01-01

    Prints are the most popular artistic technique. Due to their manufacturing procedure, they are also one of the most frequently falsified types of artwork. In terms of their economic and historic value, the chemical analysis and characterisation of coloured inks and their principal constituent materials (pigments), together with the historical and aesthetic information available in the Catalogues Raisonees, are important tools in distinguishing originals from non-original prints. The chemical characterisation and discrimination of coloured inks has test in this study. Analysis using Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and X-ray diffraction (XRD) has been done on blue pigments and inks, due to this colour is one of the most representative for the presence of organic and inorganic materials in their composition. Conclusion obtained for this colour would demonstrate the capability of the approach when it is applied to any other coloured set of inks

  18. Ink jet assisted metallization for low cost flat plate solar cells

    Science.gov (United States)

    Teng, K. F.; Vest, R. W.

    1987-01-01

    Computer-controlled ink-jet-assisted metallization of the front surface of solar cells with metalorganic silver inks offers a maskless alternative method to conventional photolithography and screen printing. This method can provide low cost, fine resolution, reduced process complexity, avoidance of degradation of the p-n junction by firing at lower temperature, and uniform line film on rough surface of solar cells. The metallization process involves belt furnace firing and thermal spiking. With multilayer ink jet printing and firing, solar cells of about 5-6 percent efficiency without antireflection (AR) coating can be produced. With a titanium thin-film underlayer as an adhesion promoter, solar cells of average efficiency 8.08 percent without AR coating can be obtained. This efficiency value is approximately equal to that of thin-film solar cells of the same lot. Problems with regard to lower inorganic content of the inks and contact resistance are noted.

  19. A facile approach to a silver conductive ink with high performance for macroelectronics

    Science.gov (United States)

    Tao, Yu; Tao, Yuxiao; Wang, Biaobing; Wang, Liuyang; Tai, Yanlong

    2013-06-01

    An unusual kind of transparent and high-efficiency organic silver conductive ink (OSC ink) was synthesized with silver acetate as silver carrier, ethanolamine as additive, and different kinds of aldehyde-based materials as reduction agents and was characterized by using a thermogravimetric analyzer, X-ray diffraction, a scanning electron microscope, and a four-point probe. The results show that different reduction agents all have an important influence on the conductive properties of the ink through a series of complex chemical reactions, and especially when formic acid or dimethylformamide was used as the reduction agent and sintered at 120°C for 30 s, the resistivity can be lowered to 6 to 9 μΩ·cm. Furthermore, formula mechanism, conductive properties, temperature, and dynamic fatigue properties were investigated systematically, and the feasibility of the OSC ink was also verified through the preparation of an antenna pattern.

  20. Digital holographic inspection for drying processes of paint films and ink dots

    Science.gov (United States)

    Yokota, M.; Aoyama, F.

    2017-06-01

    Digital holographic techniques to investigate drying processes of both paint films and ink dot is presented. The proposed technique based on digital holographic interferometry can achieve both visualization of variations and analysis of dryness of paint films in the drying process by using phase changes between two subsequent reconstructed complex amplitudes of the reflected light from the film. To follow the drying processes, holograms are recorded at a constant time interval. Phase-shifting digital holography has been applied to analyze the dryness of commercial paints applied on the metal plate. For analysis of an ink dot having diameter of a few hundred micrometers, digital holographic microscopy is applied to evaluating the time history of dryness of ink dot in the drying process. This paper describes these holographic techniques applied to the commercially available paint and ink and presents some experimental results.

  1. Discrimination of Black Ball-point Pen Inks by High Performance Liquid Chromatography (HPLC)

    International Nuclear Information System (INIS)

    Mohamed Izzharif Abdul Halim; Norashikin Saim; Rozita Osman; Halila Jasmani; Nurul Nadhirah Zainal Abidin

    2013-01-01

    In this study, thirteen types of black ball-point pen inks of three major brands were analyzed using high performance liquid chromatography (HPLC). Separation of the ink components was achieved using Bondapak C-18 column with gradient elution using water, ethanol and ethyl acetate. The chromatographic data obtained at wavelength 254.8 nm was analyzed using agglomerative hierarchical clustering (AHC) and principle component analysis (PCA). AHC was able to group the inks into three clusters. This result was supported by PCA, whereby distinct separation of the three different brands was achieved. Therefore, HPLC in combination with chemometric methods may be a valuable tool for the analysis of black ball-point pen inks for forensic purposes. (author)

  2. A fully printed ferrite nano-particle ink based tunable antenna

    KAUST Repository

    Ghaffar, Farhan A.

    2016-11-02

    Inkjet printing or printing in general has emerged as a very attractive method for the fabrication of low cost and large size electronic systems. However, most of the printed designs rely on nano-particle based metallic inks which are printed on conventional microwave substrates. In order to have a fully printed fabrication process, the substrate also need to be printed. In this paper, a fully printed multi-layer process utilizing custom Fe2O3 based magnetic ink and a silver organic complex (SOC) ink is demonstrated for tunable antennas applications. The ink has been characterized for high frequency and magnetostatic properties. Finally as a proof of concept, a microstrip patch antenna is realized using the proposed fabrication technique which shows a tuning range of 12.5 %.

  3. EPA Region 8, Memo on Desktop Printer Ink Cartridges Policy & Voluntary Printer Turn-in

    Science.gov (United States)

    This memo requests EPA Region 8 users to voluntarily turn-in their desktop printers and notifies users of the Region 8 policy to not provide maintenance or ink and toner cartridges for desktop printers.

  4. Colored inks analysis and differentiation: A first step in artistic contemporary prints discrimination

    Energy Technology Data Exchange (ETDEWEB)

    Vila, Anna [Department de Pintura, Conservacio-Restauracio, Facultat de Belles Arts, Universitat de Barcelona, C/Pau Gargallo 4, 08028 Barcelona (Spain)]. E-mail: avila@sct.ub.es; Ferrer, Nuria [Serveis Cientificotecnics, Universitat de Barcelona, C/Lluis Sole i Sabaris 1, 08028 Barcelona (Spain)]. E-mail: nferrer@sctub.es; Garcia, Jose F. [Department de Pintura, Conservacio-Restauracio, Facultat de Belles Arts, Universitat de Barcelona, C/Pau Gargallo 4, 08028 Barcelona (Spain)]. E-mail: ifgarcia@ub.edu

    2007-04-04

    Prints are the most popular artistic technique. Due to their manufacturing procedure, they are also one of the most frequently falsified types of artwork. In terms of their economic and historic value, the chemical analysis and characterisation of coloured inks and their principal constituent materials (pigments), together with the historical and aesthetic information available in the Catalogues Raisonees, are important tools in distinguishing originals from non-original prints. The chemical characterisation and discrimination of coloured inks has test in this study. Analysis using Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and X-ray diffraction (XRD) has been done on blue pigments and inks, due to this colour is one of the most representative for the presence of organic and inorganic materials in their composition. Conclusion obtained for this colour would demonstrate the capability of the approach when it is applied to any other coloured set of inks.

  5. Evaluation of the effect of heavy rare earth elements on the microstructure and mechanical and electrical properties of zirconia - Yttria ceramics

    International Nuclear Information System (INIS)

    Lazar, Dolores Ribeiro Ricci

    2002-01-01

    The use of Yttria concentrates for synthesis and processing of zirconia based ceramics, applied as structural and solid electrolyte materials, was investigated in this work. Terbium, dysprosium, holmium, erbium and ytterbium are chemical elements, classified as heavy rare earths, that can be found in those concentrates due to their association with yttrium ores. The ceramic characteristics were compared to zirconia - Yttria and zirconia - Yttria - rare earth oxide systems. The dopant content was 3 and 9 mol%. The raw materials were prepared by the coprecipitation route using solutions from the chemical processing of zircon and monazite ores and obtained by dissolution of high purity rare earth oxides. In the first part of this work, calcination, milling and ceramic processing were studied to produce ceramics with densities up to 95% TD. Samples were prepared in optimized conditions for the evaluation of the effect of each heavy rare earth element. Powders were characterized by chemical analysis. X-ray diffraction, scanning and transmission electron microscopy, gas adsorption (BET) and laser diffraction for the determination of the agglomerate size distributions. Green pellets were characterized by mercury porosimetry and the sintering kinetic was studied by dilatometry. The characterization of the as-sintered pellets was performed by the apparent density measurement (Archimedes method). X-ray diffraction, microstructure analysis by scanning and transmission electron microscopy, Vickers indentation tests for hardness and fracture toughness determination, dynamic mechanical analysis for the elastic modulus measurement, and impedance spectroscopy for electrical resistivity measurement. It was observed that the presence of heavy rare earths in a concentrate containing 85 wt% of Yttria has no significant influence on the properties of zirconia based ceramics. TZP ceramics, containing 3 mol% of dopants, have grain size smaller than 0.4μm, and Vickers hardness and

  6. Development of a nano structured system based on zirconia and Co nanoparticles for thermoluminescent applications: sensor of gamma and UV radiation

    International Nuclear Information System (INIS)

    Villa S, G.

    2014-01-01

    Powders of zirconium IV oxide as well as systems composed of zirconia nano crystals and cobalt nanoparticles (ZrO 2 :NPCo) with dimensions of nanometers were synthesized by the sol-gel method. Zirconia and ZrO 2 :NPCo systems have crystalline structure tetragonal or monoclinic is the heat treatment was to 500 and 1000 degrees Celsius respectively. The characterization of the synthesized materials consisted of a morphological and structural analysis, the information obtained was correlated to its thermoluminescent response induced by gamma and ultraviolet radiation. Thermoluminescent behavior was analyzed on different concentrations of cobalt nanoparticles incorporated during the synthesis process of the zirconium oxide. The monoclinic structure has the highest sensitivity thermoluminescent induced by ultraviolet and gamma radiation. Moreover, the thermoluminescence intensity decreased considerably in ZrO 2 :NPCo systems and was induced the growth of a glow peak at 280 degrees Celsius. In most of the materials analyzed the relation of the thermoluminescence intensity depending the time of irradiation with ultraviolet light showed the saturation of the traps in the material after 60 s of irradiation. Using gamma radiation is observed a behavior linear in the applied dose range between 0.25 Gy and 450 Gy. The growth of a glow peak at 280 degrees Celsius is the most important change in the thermoluminescence characteristics of zirconia. The ZrO 2 :NPCo systems can be used in the development of thermoluminescent dosimeters for detecting gamma radiation fields mainly. (Author)

  7. Zirconia implants and peek restorations for the replacement of upper molars

    Directory of Open Access Journals (Sweden)

    José María Parmigiani-Izquierdo

    2017-02-01

    Full Text Available Abstract Background One of the disadvantages of the zirconia implants is the lack of elasticity, which is increased with the use of ceramic or zirconia crowns. The consequences that could result from this lack of elasticity have led to the search for new materials with improved mechanical properties. Case presentation A patient who is a 45-year-old woman, non-smoker and has no medical record of interest with a longitudinal fracture in the palatal root of molar tooth 1.7 and absence of tooth 1.6 was selected in order to receive a zirconia implant with a PEEK-based restoration and a composite coating. The following case report describes and analyses treatment with zirconia implants in molars following a flapless surgical technique. Zirconia implants are an alternative to titanium implants in patients with allergies or who are sensitive to metal alloys. However, one of the disadvantages that they have is their lack of elasticity, which increases with the use of ceramic or zirconia crowns. The consequences that can arise from this lack of elasticity have led to the search for new materials with better mechanical properties to cushion occlusal loads. PEEK-based restoration in implant prosthetics can compensate these occlusal forces, facilitating cushioning while chewing. Conclusion This procedure provides excellent elasticity and resembles natural tooth structure. This clinical case suggests that PEEK restorations can be used in zirconia implants in dentistry.

  8. Osseointegration of zirconia implants: an SEM observation of the bone-implant interface.

    Science.gov (United States)

    Depprich, Rita; Zipprich, Holger; Ommerborn, Michelle; Mahn, Eduardo; Lammers, Lydia; Handschel, Jörg; Naujoks, Christian; Wiesmann, Hans-Peter; Kübler, Norbert R; Meyer, Ulrich

    2008-11-06

    The successful use of zirconia ceramics in orthopedic surgery led to a demand for dental zirconium-based implant systems. Because of its excellent biomechanical characteristics, biocompatibility, and bright tooth-like color, zirconia (zirconium dioxide, ZrO2) has the potential to become a substitute for titanium as dental implant material. The present study aimed at investigating the osseointegration of zirconia implants with modified ablative surface at an ultrastructural level. A total of 24 zirconia implants with modified ablative surfaces and 24 titanium implants all of similar shape and surface structure were inserted into the tibia of 12 Göttinger minipigs. Block biopsies were harvested 1 week, 4 weeks or 12 weeks (four animals each) after surgery. Scanning electron microscopy (SEM) analysis was performed at the bone implant interface. Remarkable bone attachment was already seen after 1 week which increased further to intimate bone contact after 4 weeks, observed on both zirconia and titanium implant surfaces. After 12 weeks, osseointegration without interposition of an interfacial layer was detected. At the ultrastructural level, there was no obvious difference between the osseointegration of zirconia implants with modified ablative surfaces and titanium implants with a similar surface topography. The results of this study indicate similar osseointegration of zirconia and titanium implants at the ultrastructural level.

  9. Therapeutic Significance of Loligo vulgaris (Lamarck, 1798) ink Extract: A Biomedical Approach

    Science.gov (United States)

    Nadarajah, Sri Kumaran; Vijayaraj, Radha; Mani, Jayaprakashvel

    2017-01-01

    Background: The squid ink extract is well known for its biomedical properties. Objective: In this study, squid Loligo vulgaris was collected from Tuticorin costal water, Bay of Bengal, India. Materials and Methods: Proximate composition of the crude squid ink was studied and found to have protein as the major component over lipid and carbohydrates. Further, bioactive fractions of squid ink were extracted with ethanol, and therapeutic applications such as hemolytic, antioxidant, antimicrobial, and in vitro anti-inflammatory properties were analyzed using standard methods. Results: In hemolytic assay, the squid ink extract exhibited a maximum hemolytic activity of 128 hemolytic unit against tested erythrocytes. In DPPH assay, the ethanolic extract of squid ink has exhibited an antioxidant activity of 83.5%. The squid ink was found to be potent antibacterial agent against the pathogens tested. 200 μL of L. vulgaris ink extract showed remarkable antibacterial activity as zone of inhibition against Escherichia coli (28 mm), Klebsiella pneumoniae (22 mm), Pseudomonas aeruginosa (21 mm), and Staphylococcus aureus (24 mm). The 68.9% inhibition of protein denaturation by the squid ink extract indicated that it has very good in vitro anti-inflammatory properties. The Fourier transform infrared spectroscopy analysis of the ethanolic extracts of the squid ink indicated the presence of functional groups such as 1° and 2° amines, amides, alkynes (terminal), alkenes, aldehydes, nitriles, alkanes, aliphatic amines, carboxylic acids, and alkyl halides, which complements the biochemical background of therapeutic applications. Conclusion: Hence, results of this study concluded that the ethanolic extract of L. vulgaris has many therapeutic applications such as antimicrobial, antioxidant, and anti-inflammatory activities. SUMMARY Squid ink is very high in a number of important nutrients. It’s particularly high in antioxidants for instance, which as well all know help to protect

  10. Remediation of a contaminated soil by Ni+2 after application of biochar prepared from de-inking paper sludge: Influence on enzyme activities

    Science.gov (United States)

    Gascó, G.; Paz-Ferreiro, J.; Araujo, F.; Guerrero, F.; Méndez, A.

    2012-04-01

    In recent years, an increasing proportion of recycled fibres are used in paper industries due to their important environmental and economical benefits. A ton of pulp produced from recycled paper requires 60% less energy to manufacture than a ton of bleached virgin kraft pulp [1]. However, removing the ink, clay, coatings and contaminants from waste paper in order to produce recycled paper creates large amounts of de-inking paper sludge (DPS). Nowadays, more than 200000 t of DPS were produced in Spain. DPS can be used as amendment due to their high organic matter [2] but the high C/N ratio and the heavy metal content can limit its use. For this reason, the preparation of biochar obtained from pyrolysis process for water remediation [3] and soil contaminated by heavy metal can be an valorisation alternative. The main objective of this work is to study the influence of the biochar application prepared from de-inking sewage sludge in the soil enzyme activities of a contaminated soil by Ni+2 at two different concentrations. For this reason, an incubation experiment was performed and several enzymatic activities (dehydrogenase, b-glucosidase, phosphomoesterase and arylsulphatase) were monitored. The study was completed studying the influence of the biochar application in plant-available metals from soil. [1] Thompson C.G. 1992. Recycled Papers. The Essential Guide, MIT Press, Cambridge. [2] Barriga S., Méndez A., Cámara J., Guerrero F., Gascó G. 2010. Agricultural valorisation of de-inking paper sludge as organic amendment in different soils: Thermal study. Journal of Thermal Analysis and Calorimetry 99: 981-986 [3] Méndez A., Barriga S., Fidalgo J.M., Gascó G. 2009. Adsorbent materials from paper industry waste materials and their use in Cu(II) removal from water. Journal of Hazardous Materials 165: 736-743.

  11. Thermal Analysis of Braille Formed by Using Screen Printing and Inks with Thermo Powder

    OpenAIRE

    Svіtlana HAVENKO; Victoria KOCHUBEI; Marta LABETSKA; Svitlana KHADZHYNOVA; Edmundas KIBIRKŠTIS; Ingrida Venytė

    2015-01-01

    In order to improve the integration of blind people into society, suitable conditions should be provided for them. The expansion of Braille (BR) use could serve the purpose. Depending on the materials used for Braille, it can be formed or printed in different ways: embossing, screen printing, thermoforming, digital printing. The aim of this research is to determine the effect of thermal properties of screen printing inks and inks with thermo-powder on the qualitative parameters of Braille. Sc...

  12. Biomimetic Inks Based on Cellulose Nanofibrils and Cross-Linkable Xylans for 3D Printing.

    Science.gov (United States)

    Markstedt, Kajsa; Escalante, Alfredo; Toriz, Guillermo; Gatenholm, Paul

    2017-11-22

    This paper presents a sustainable all-wood-based ink which can be used for 3D printing of constructs for a large variety of applications such as clothes, furniture, electronics, and health care products with a customized design and versatile gel properties. The 3D printing technologies where the material is dispensed in the form of liquids, so called inks, have proven suitable for 3D printing dispersions of cellulose nanofibrils (CNFs) because of their unique shear thinning properties. In this study, novel inks were developed with a biomimetic approach where the structural properties of cellulose and the cross-linking function of hemicelluloses that are found in the plant cell wall were utilized. The CNF was mixed with xylan, a hemicellulose extracted from spruce, to introduce cross-linking properties which are essential for the final stability of the printed ink. For xylan to be cross-linkable, it was functionalized with tyramine at different degrees. Evaluation of different ink compositions by rheology measurements and 3D printing tests showed that the degree of tyramine substitution and the ratio of CNFs to xylan-tyramine in the prepared inks influenced the printability and cross-linking density. Both two-layered gridded structures and more complex 3D constructs were printed. Similarly to conventional composites, the interactions between the components and their miscibility are important for the stability of the printed and cross-linked ink. Thus, the influence of tyramine on the adsorption of xylan to cellulose was studied with a quartz crystal microbalance to verify that the functionalization had little influence on xylan's adsorption to cellulose. Utilizing xylan-tyramine in the CNF dispersions resulted in all-wood-based inks which after 3D printing can be cross-linked to form freestanding gels while at the same time, the excellent printing properties of CNFs remain intact.

  13. Effect of temperature on electrical conductance of inkjet-printed silver nanoparticle ink during continuous wave laser sintering

    International Nuclear Information System (INIS)

    Lee, Dae-Geon; Kim, Dong Keun; Moon, Yoon-Jae; Moon, Seung-Jae

    2013-01-01

    To determine the effect of temperature on the specific electrical conductance of inkjet-printed ink during continuous wave laser sintering, the temperature of the sintered ink was estimated. The ink, which contained 34 wt.% silver nanoparticles with an average size of approximately 50 nm, was inkjet-printed onto a liquid crystal display glass substrate. The printed ink was irradiated with a 532 nm continuous wave laser for 60 s with various laser intensities. During laser irradiation, the in-situ electrical conductance of the sintered ink was measured to estimate the transient thermal conductivity of the ink. The electrical conductance and thermal conductivity of the ink was coupled to obtain the transient temperature by applying the Wiedemann–Franz law to a two-dimensional transient heat conduction equation. The electrical conductance of laser-sintered ink was highly dependent on the sintering temperature of the ink. - Highlights: • The in-situ electrical conductance was measured during the laser sintering process. • Wiedemann–Franz law coupled the electrical conductance with transient temperature. • The transient temperature of the laser-sintered Ag nanoparticle ink was estimated

  14. Ultrastructural Comparison of Processing of Protein and Pigment in the Ink Gland of Four Species of Sea Hares

    Directory of Open Access Journals (Sweden)

    Jeffrey S. Prince

    2015-01-01

    Full Text Available The ink glands of four sea hare species (Aplysia californica, A. parvula, A. juliana, and Dolabrifera dolabrifera were compared to determine where ink protein is synthesized, how it is incorporated into protein storage vesicles, and the degree of variation in the structure of the ink gland. Ink protein was synthesized in RER cells and stored in amber and white vesicles. Lack of competent RER cells in the ink gland of D. dolabrifera was correlated with the absence of ink protein. Ink protein had similar characteristics in all three Aplysia species but, again, it was absent in D. dolabrifera. Its uptake involved pinocytosis by protein vesicle cell membranes. Granulate cells showed little variation in structure among the four species, the opposite was the case for RER cells. The conversion of the red algal pigment, phycoerythrin, to phycoerythrobilin (PEB occurs in the digestive gland but the change of PEB to aplysioviolin (APV, the form of pigment released by the ink gland, occurs in the ink gland itself by both granulate cells and pigment vesicles. The literature describes five types of vesicles based upon color and contents in the ink gland of these four species. We report only three types of vesicle: colored (purple, protein (white and amber, and transparent (includes clear vesicles.

  15. 3D-characterization of the veneer-zirconia interface using FIB nano-tomography.

    Science.gov (United States)

    Mainjot, Amélie K; Douillard, Thierry; Gremillard, Laurent; Sadoun, Michaël J; Chevalier, Jérôme

    2013-02-01

    The phenomena occurring during zirconia frameworks veneering process are not yet fully understood. In particular the study of zirconia behavior at the interface with the veneer remains a challenge. However this interface has been reported to act on residual stress in the veneering ceramic, which plays a significant role in clinical failures such as chipping. The objective of this study was thus to investigate the veneer-zirconia interface using a recent 3D-analysis tool and to confront these observations to residual stress measurements in the veneering ceramic. Two cross-sectioned bilayered disc samples (veneer on zirconia), exhibiting different residual stress profiles in the veneering ceramic, were investigated using 2D and 3D imaging (respectively Scanning Electron Microscopy (SEM) and Focused Ion Beam nanotomography (FIB-nt), associated with chemical analysis by Energy Dispersive X-ray Spectroscopy (EDS). The observations did not reveal any structural change in the bulk of zirconia layer of both samples. However the presence of structural alterations and sub-surface microcracks were highlighted in the first micrometer of zirconia surface, exclusively for the sample exhibiting interior tensile stress in the veneering ceramic. No interdiffusion phenomena were observed. FIB nanotomography was proven to be a powerful technique to study the veneer-zirconia interface. The determination of the origin and the nature of zirconia alterations need to be further studied. The results of the present study support the hypothesis that zirconia surface property changes could be involved in the development of tensile stress in the veneering ceramic, increasing the risk of chipping. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  16. Phase transformation of dental zirconia following artificial aging.

    Science.gov (United States)

    Lucas, Thomas J; Lawson, Nathaniel C; Janowski, Gregg M; Burgess, John O

    2015-10-01

    Low-temperature degradation (LTD) of yttria-stabilized zirconia can produce increased surface roughness with a concomitant decrease in strength. This study determined the effectiveness of artificial aging (prolonged boiling/autoclaving) to induce LTD of Y-TZP (yttria-tetragonal zirconia-polycrystals) and used artificial aging for transformation depth progression analyses. The null hypothesis is aging techniques tested produce the same amount of transformation, transformation is not time/temperature dependent and LTD causes a constant transformation throughout the Y-TZP samples. Dental-grade Y-TZP samples were randomly divided into nine subgroups (n = 5): as received, 3.5 and 7 day boiling, 1 bar autoclave (1, 3, 5 h), and 2 bar autoclave (1, 3, 5 h). A 4-h boil treatment (n = 2) was performed post-experiment for completion of data. Transformation was measured using traditional X-ray diffraction and low-angle X-ray diffraction. The fraction of t → m transformation increased with aging time. The 3.5 day boil and 2 bar 5 h autoclave produced similar transformation results, while the 7 day boiling treatment revealed the greatest transformation. The surface layer of the aged specimen underwent the most transformation while all samples displayed decreasing transformation with depth. Surface transformation was evident, which can lead to rougher surfaces and increased wear of opposing dentition/materials. Therefore, wear studies addressing LTD of Y-TZP are needed utilizing accelerated aging. © 2014 Wiley Periodicals, Inc.

  17. Plastic deformation of cubic zirconia single crystals at 1400 C

    International Nuclear Information System (INIS)

    Baufeld, B.; Baither, D.; Bartsch, M.; Messerschmidt, U.

    1998-01-01

    Cubic zirconia single crystals stabilized with 11 mol% yttria were deformed in air at 1400 C and around 1200 C at different strain rates along [1 anti 12] and [100] compression directions. The strain rate sensitivity of the flow stress was determined by strain rate cycling and stress relaxation tests. The microstructure of the deformed specimens was investigated by transmission high-voltage electron microscopy, including contrast extinction analysis for determining the Burgers vectors as well as stereo pairs and wide-angle tilting experiments to find the active slip planes. At deformation along [1 anti 12], the primary and secondary slip planes are of {100} type. Previous experiments had shown that the dislocations move easily on these planes in an athermal way. During deformation along [100], mainly dislocations on {100} planes are activated, which move in a viscous way by the aid of thermal activation. The discussion of the different deformation behaviours during deformation along [1 anti 12] and [100] is based on the different dynamic properties of dislocations and the fact that recovery is an essential feature of the deformation of cubic zirconia at 1400 C. The results on the shape of the deformation curve and the strain rate sensitivity of the flow stress are partly at variance with those of previous authors. (orig.)

  18. Lifetime estimation of zirconia ceramics by linear ageing kinetics

    International Nuclear Information System (INIS)

    Zhang, Fei; Inokoshi, Masanao; Vanmeensel, Kim; Van Meerbeek, Bart; Naert, Ignace; Vleugels, Jef

    2015-01-01

    Up to now, the ageing kinetics of zirconia ceramics were mainly derived from the sigmoidal evolution of the surface phase transformation as a function of time, as quantified by means of X-ray diffraction (XRD). However, the transformation propagation into the material should be better to monitor the ageing kinetics. In this work, μ-Raman spectroscopy was used to quantitatively measure the transformation profiles in depth as a function of ageing time at 160 °C, 140 °C, 134 °C and 110 °C. A linear relationship between the transformed depth and the ageing time was observed for all investigated yttria stabilized tetragonal zirconia polycrystals (3Y-TZP). Furthermore, the μ-Raman investigation of residual stresses in the subsurface of aged 3Y-TZPs showed that the highest tensile stress was located just ahead of the transformation front, indicating the key responsibility of stress accumulation for transformation front propagating into the material. Moreover, the linear kinetics of the transformation propagation were more accurate to calculate the apparent activation energy of the ageing process and allowed a more straightforward estimation of the lifetime of 3Y-TZP at body temperature, as compared to the conventional ageing kinetic parameters obtained from the surface transformation analysis by XRD

  19. Dielectric properties of alumina/zirconia composites at millimeter wavelengths

    International Nuclear Information System (INIS)

    Molla, J.; Heidinger, R.; Ibarra, A.; Link, G.

    1994-01-01

    Alumina-zirconia composites with ZrO 2 contents up to 20% and negligible porosity were investigated at millimeter (mm) wavelengths to determine the changes appearing in the dielectric properties of pure alumina ceramics when unstabilized or partially stabilized ZrO 2 is added to improve the mechanical strength. It is demonstrated that it essential to distinguish between the contributions of the monoclinic and the tetragonal phase of zirconia (m-ZrO 2 , t-ZrO 2 ). Permittivity is raised with increasing content of either phases; the effective permittivity can be assessed by the rule of mixtures (Maxwell-Garnett formulation of the generalized Clasussius-Mossotti relation) using permittivity values of 10 for Al 2 O 3 , 14-21 for m-ZrO 2 and 40-45 for t-ZrO 2 . The permittivity data show only a small variation in the investigated range of 9-145 GHz. For the dielectric loss, there is evidence of a predominant contribution of m-ZrO 2 ; in addition, the marked increase in loss with frequency becomes sharper. The t-ZrO 2 , which is responsible for strengthening, does not show any significant influence on losses. It is therefore concluded, that ZrO 2 strengthening of alumina is feasible without affecting mm-wave losses at room temperature as long as the presence of m-ZrO 2 is avoided

  20. Osteoblast response to zirconia surfaces with different topographies

    Energy Technology Data Exchange (ETDEWEB)

    Herath, H.M.T.U. [Department of Medical Laboratory Science, Faculty of Allied Health Sciences, University of Peradeniya (Sri Lanka); Di Silvio, L. [Guy' s, King' s and St Thomas' Medical and Dental Institute, King' s College London, London SE1 9RT (United Kingdom); Evans, J.R.G., E-mail: j.r.g.evans@ucl.ac.uk [Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom)

    2015-12-01

    Zirconia-3 mol% yttria ceramics were prepared with as-sintered, abraded, polished, and porous surfaces in order to explore the attachment, proliferation and differentiation of osteoblast-like cells. After modification, all surfaces were heated to 600 °C to extinguish traces of organic contamination. All surfaces supported cell attachment, proliferation and differentiation but the surfaces with grain boundary grooves or abraded grooves provided conditions for enhanced initial cell attachment. Nevertheless, overall cell proliferation and total DNA were highest on the polished surface. Zirconia sintered at a lower temperature (1300 °C vs. 1450 °C) had open porosity and presented reduced proliferation as assessed by alamarBlue™ assay, possibly because the openness of the pores prevented cells developing a local microenvironment. All cells retained the typical polygonal morphology of osteoblast-like cells with variations attributable to the underlying surface notably alignment along the grooves of the abraded surface. - Highlights: • Biocompatibility of chemically identical, topologically different ZrO{sub 2} was tested. • ZrO{sub 2} promoted cell adhesion, proliferation, differentiation and nodule formation. • Proliferation was high on polished ZrO{sub 2} but initial recruitment was high on abraded ZrO{sub 2}. • With open porosity, proliferation was low; cells cannot establish a microenvironment.

  1. Phase stability in yttria-stabilized zirconia from first principles

    Energy Technology Data Exchange (ETDEWEB)

    Carbogno, Christian; Scheffler, Matthias [Materials Department, University of California, Santa Barbara, CA (United States); Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin (Germany); Levi, Carlos G.; Van de Walle, Chris G. [Materials Department, University of California, Santa Barbara, CA (United States)

    2012-07-01

    Zirconia based ceramics are of pivotal importance for a variety of industrial technologies, e.g., for thermal barrier coatings in gas and airplane turbines. Naturally, the stability of such coatings at elevated temperatures plays a critical role in these applications. It is well known that an aliovalent doping of tetragonal ZrO{sub 2} with yttria, which induces oxygen vacancies due to charge conservation, increases its thermodynamic stability. However, the atomistic mechanisms that determine the phase stability of such yttria-stabilized Zirconia (YSZ) coatings are not yet fully understood. In this work, we use density functional theory calculations to assess the electronic structure of the different YSZ polymorphs at various levels of doping. With the help of population analysis schemes, we are able to unravel the intrinsic mechanisms that govern the interaction in YSZ and that can so explain the relative stabilities of the various polymorphs. We critically compare our results to experimental measurements and discuss the implications of our findings with respect to other oxides.

  2. Basic properties of a zirconia based fuel material for LWRs

    International Nuclear Information System (INIS)

    Degueldre, C.; Paratte, J.M.

    1997-01-01

    The properties of zirconia cubic solid solutions doped with yttria, erbia and ceria or thoria are investigated with emphasis on the potential use of this material as inert matrix fuel for plutonium incineration in a light water reactor (LWR). The material is selected on the basis of its neutronic properties. Zr and Y are not neutron absorbers. Among the rare earth elements, Er was identified as a suitable burnable poison. The high density cubic solid solution is stable for a rather large range of compositions and from room temperature up to about 3000 K. Samples irradiated under low and high energy Xe ion irradiation up to a fluence of 1.8.10 16 Xe.cm -2 were investigated by transmission electron microscopy. Low energy (60 keV) Xe ions did not produce amorphization. From the observed bubble formation, swelling values during irradiation at room temperature or at high temperature (925 K) were estimated to be 0.1-0.72% by volume. Furthermore, no amorphization was obtained by Xe irradiation under extreme conditions such as high energy (1.5 MeV) Xe ion irradiation and low temperature (20 K). This confirms the robustness of this material and argues in favour of the selection of a zirconia based material as an advanced nuclear fuel for plutonium incineration. (author) 5 figs., 1 tab., 17 refs

  3. Effect of environmental dust particles on laser textured yttria-stabilized zirconia surface in humid air ambient

    Science.gov (United States)

    Yilbas, B. S.; Ali, H.; Al-Sharafi, A.; Al-Sulaiman, F.; Karatas, C.

    2018-05-01

    Zirconium nitride is used as a selective surface for concentrated solar heating applications and one of the methods to form a zirconium nitride is texturing of zirconia surface by a high intensity laser beam under high pressure nitrogen gas environment. Laser texturing also provides hydrophobic surface characteristics via forming micro/nano pillars at the surface; however, environmental dust settlement on textured surface influences the surface characteristics significantly. In the present study, laser texturing of zirconia surface and effects of the dust particles on the textured surface in a humid air ambient are investigated. Analytical tools are used to assess the morphological changes on the laser textured surface prior and after the dust settlement in the humid air ambient. It is found that laser textured surface has hydrophobic characteristics. The mud formed during condensate of water on the dust particles alters the characteristics of the laser textured surface. The tangential force required to remove the dry mud from the textured surface remains high; in which case, the dried liquid solution at the mud-textured surface interface is responsible for the strong adhesion of the dry mud on the textured surface. The textured surface becomes hydrophilic after the dry mud was removed from the surface by a desalinated water jet.

  4. Three-dimensional finite element analysis of zirconia all-ceramic cantilevered fixed partial dentures with different framework designs.

    Science.gov (United States)

    Miura, Shoko; Kasahara, Shin; Yamauchi, Shinobu; Egusa, Hiroshi

    2017-06-01

    The purpose of this study were: to perform stress analyses using three-dimensional finite element analysis methods; to analyze the mechanical stress of different framework designs; and to investigate framework designs that will provide for the long-term stability of both cantilevered fixed partial dentures (FPDs) and abutment teeth. An analysis model was prepared for three units of cantilevered FPDs that assume a missing mandibular first molar. Four types of framework design (Design 1, basic type; Design 2, framework width expanded buccolingually by 2 mm; Design 3, framework height expanded by 0.5 mm to the occlusal surface side from the end abutment to the connector area; and Design 4, a combination of Designs 2 and 3) were created. Two types of framework material (yttrium-oxide partially stabilized zirconia and a high precious noble metal gold alloy) and two types of abutment material (dentin and brass) were used. In the framework designs, Design 1 exhibited the highest maximum principal stress value for both zirconia and gold alloy. In the abutment tooth, Design 3 exhibited the highest maximum principal stress value for all abutment teeth. In the present study, Design 4 (the design with expanded framework height and framework width) could contribute to preventing the concentration of stress and protecting abutment teeth. © 2017 Eur J Oral Sci.

  5. Radiative transfer analysis of the effect of ink dot area on color phase in inkjet printing

    International Nuclear Information System (INIS)

    Gonome, Hiroki; Ishikawa, Yuki; Kono, Takahiro; Yamada, Jun

    2017-01-01

    This study discusses a mechanism of inkjet printing and investigates the effect of ink contrast on the color phase of the printed object. Inkjet printing is a popular printing method for home use, but its color repeatability is occasionally broken. To verify this problem, we calculated the radiative transfer equation on the surface of an object printed by an inkjet printer, and the color was quantitatively estimated. The ink dot area and spectral reflectance of the printed samples were measured. Furthermore, the spectral reflectance of the objects printed with different dot areas were theoretically calculated. By comparing the measured and calculated reflectance, we estimated the scattering coefficient of the paper and absorption coefficient of the ink. We quantitatively calculated the color with the HSV color system. The hue changed with dot area rate. It is considered that this is caused by the broad range of the spectral absorption coefficients of inks. We believe that this study will aid the development of ink without color change and improve the color repeatability of inkjet printers. - Highlights: • Radiative transfer on the surface of an object printed by an inkjet printer is modeled. • Spectral reflectance of the printed samples are measured and calculated. • The hue changes with dot area rate because of the broad range of the spectral absorption coefficients of inks.

  6. Forensic analysis of ballpoint pen inks using paper spray mass spectrometry.

    Science.gov (United States)

    da Silva Ferreira, Priscila; Fernandes de Abreu e Silva, Débora; Augusti, Rodinei; Piccin, Evandro

    2015-02-07

    A novel analytical approach based on paper spray mass spectrometry (PS-MS) is developed for a fast and effective forensic analysis of inks in documents. Ink writings made in ordinary paper with blue ballpoint pens were directly analyzed under ambient conditions without any prior sample preparation. Firstly, the method was explored on a set of distinct pens and the results obtained in the positive ion mode, PS(+)-MS, demonstrated that pens from different brands provide typical profiles. Simple visual inspection of the PS(+)-MS led to the distinction of four different combinations of dyes and additives in the inks. Further discrimination was performed by using the concept of relative ion intensity (RII), owing to the large variability of dyes BV3 and BB26 regarding their demethylated homologues. Following screening and differentiation studies, the composition changes of ink entries subjected to light exposure were also monitored by PS-MS. The results of these tests revealed distinct degradation behaviors which were reflected on the typical chemical profiles of the studied inks, attesting that PS-MS may be also useful to verify the fading of dyes thus allowing the discrimination of entries on a document. As proof of concept experiments, PS-MS was successfully utilized for the analysis of archived documents and characterization of overlapped ink lines made on simulated forged documents.

  7. A New 3D Printing Strategy by Harnessing Deformation, Instability, and Fracture of Viscoelastic Inks.

    Science.gov (United States)

    Yuk, Hyunwoo; Zhao, Xuanhe

    2018-02-01

    Direct ink writing (DIW) has demonstrated great potential as a multimaterial multifunctional fabrication method in areas as diverse as electronics, structural materials, tissue engineering, and soft robotics. During DIW, viscoelastic inks are extruded out of a 3D printer's nozzle as printed fibers, which are deposited into patterns when the nozzle moves. Hence, the resolution of printed fibers is commonly limited by the nozzle's diameter, and the printed pattern is limited by the motion paths. These limits have severely hampered innovations and applications of DIW 3D printing. Here, a new strategy to exceed the limits of DIW 3D printing by harnessing deformation, instability, and fracture of viscoelastic inks is reported. It is shown that a single nozzle can print fibers with resolution much finer than the nozzle diameter by stretching the extruded ink, and print various thickened or curved patterns with straight nozzle motions by accumulating the ink. A quantitative phase diagram is constructed to rationally select parameters for the new strategy. Further, applications including structures with tunable stiffening, 3D structures with gradient and programmable swelling properties, all printed with a single nozzle are demonstrated. The current work demonstrates that the mechanics of inks plays a critical role in developing 3D printing technology. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Sepia ink as a surrogate for colloid transport tests in porous media

    Science.gov (United States)

    Soto-Gómez, Diego; Pérez-Rodríguez, Paula; López-Periago, J. Eugenio; Paradelo, Marcos

    2016-08-01

    We examined the suitability of the ink of Sepia officinalis as a surrogate for transport studies of microorganisms and microparticles in porous media. Sepia ink is an organic pigment consisted on a suspension of eumelanin, and that has several advantages for its use as a promising material for introducing the frugal-innovation in the fields of public health and environmental research: very low cost, non-toxic, spherical shape, moderate polydispersivity, size near large viruses, non-anomalous electrokinetic behavior, low retention in the soil, and high stability. Electrokinetic determinations and transport experiments in quartz sand columns and soil columns were done with purified suspensions of sepia ink. Influence of ionic strength on the electrophoretic mobility of ink particles showed the typical behavior of polystyrene latex spheres. Breakthrough curve (BTC) and retention profile (RP) in quartz sand columns showed a depth dependent and blocking adsorption model with an increase in adsorption rates with the ionic strength. Partially saturated transport through undisturbed soil showed less retention than in quartz sand, and matrix exclusion was also observed. Quantification of ink in leachate fractions by light absorbance is direct, but quantification in the soil profile with moderate to high organic matter content was rather cumbersome. We concluded that sepia ink is a suitable cheap surrogate for exploring transport of pathogenic viruses, bacteria and particulate contaminants in groundwater, and could be used for developing frugal-innovation related with the assessment of soil and aquifer filtration function, and monitoring of water filtration systems in low-income regions.

  9. Microstructural and Process Characterization of Conductive Traces Printed from Ag Particulate Inks

    Directory of Open Access Journals (Sweden)

    Eric MacDonald

    2011-05-01

    Full Text Available Conductive inks are key enablers for the use of printing techniques in the fabrication of electronic systems. Focus on the understanding of aspects controlling the electrical performance of conductive ink is paramount. A comparison was made between microparticle Ag inks and an Ag nanoparticle ink. The microstructures resulting from thermal cure processes were characterized morphologically and also in terms of their effect on the resistivity of printed traces. For microparticle inks, the variability of resistivity measurements between samples as defined by coefficient of variation (CV was greater than 0.1 when the resistivity was 10 to 50 times that of bulk Ag. When the resistivity was lower (~1.4 times that of bulk Ag the CV of sample sets was less than 0.1. In the case of the nanoparticle ink, resistivity was found to decrease by a factor ranging from 1.2 to 1.5 after doubling the amount of layers printed prior to curing though it was expected to remain the same. Increasing the amount of layers printed also enhanced the sintering process.

  10. Influence of Gloss and Surface Roughness of Coated Ink Jet Papers on Print Uniformity

    Directory of Open Access Journals (Sweden)

    Ivana Jurič

    2013-12-01

    Full Text Available The final print quality depends on the quality of the digital image as well as the properties of the printing system, the inks and the paper used. One of the most widely used digital printing technologies is ink jet, where ink is ejected directly onto a substrate from a jet device driven by an electronic signal. Most ink jet inks have low viscosity and low surface tension, which pose high demands upon the surface properties of the paper. The aim of this study was to investigate the influence of paper properties of commercially available papers suitable for ink jet printing on print mottle, non-uniformity. We used two high glossy, one glossy, one semi-glossy and two matte papers. For the assessment of the surface properties, we measured surface roughness with the portable Roughness Tester TR 200. We also measured surface gloss with QIP Glossmaster. To characterise the print mottle we used the image analysis method – Gray level co-occurrence matrix (GLCM. Print mottle was estimated according to five GLCM parameters: Contrast, Correlation, Entropy, Energy and Homogeneity. Results obtained in this paper showed that the surface properties of paper are not in any direct relation with print uniformity.

  11. Formation of metastable tetragonal zirconia nanoparticles: Competitive influence of the dopants and surface state

    Energy Technology Data Exchange (ETDEWEB)

    Gorban, Oksana, E-mail: matscidep@aim.com [Donetsk Institute for Physics and Engineering named after A.A. Galkin of the NAS of Ukraine, Nauki av. 46, Kyiv 03680 (Ukraine); Synyakina, Susanna; Volkova, Galina; Gorban, Sergey; Konstantiova, Tetyana [Donetsk Institute for Physics and Engineering named after A.A. Galkin of the NAS of Ukraine, Nauki av. 46, Kyiv 03680 (Ukraine); Lyubchik, Svetlana, E-mail: s_lyubchik@yahoo.com [REQUIMTE, Universida de Nova de Lisboa, 2829-516 Caparica (Portugal)

    2015-12-15

    The effect of the surface modification of the nanoparticles of amorphous and crystalline partially stabilized zirconia by fluoride ions on stability of the metastable tetragonal phase was investigated. Based on the DSC, titrimetry and FTIR spectroscopy data it was proven that surface modification of the xerogel resulted from an exchange of the fluoride ions with the basic OH groups. The effect of the powder pre-calcination temperature before modification on the formation of metastable tetragonal phase in partially stabilized zirconia was investigated. It was shown that the main factor of tetragonal zirconia stabilization is the state of nanoparticles surface at pre-crystallization temperatures.

  12. Effects of surface treatment on bond strength between dental resin agent and zirconia ceramic

    Energy Technology Data Exchange (ETDEWEB)

    Moradabadi, Ashkan [Department of Electrochemistry, Universität Ulm, Ulm (Germany); Roudsari, Sareh Esmaeily Sabet [Department of Optoelectonics, Universität Ulm, Ulm (Germany); Yekta, Bijan Eftekhari [School of Materials Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Rahbar, Nima, E-mail: nrahbar@wpi.edu [Department of Civil and Environmental Engineering, Worcester Polytechnic Institute, Worcester, MA 01609 (United States)

    2014-01-01

    This paper presents the results of an experimental study to understand the dominant mechanism in bond strength between dental resin agent and zirconia ceramic by investigating the effects of different surface treatments. Effects of two major mechanisms of chemical and micromechanical adhesion were evaluated on bond strength of zirconia to luting agent. Specimens of yttrium-oxide-partially-stabilized zirconia blocks were fabricated. Seven groups of specimens with different surface treatment were prepared. 1) zirconia specimens after airborne particle abrasion (SZ), 2) zirconia specimens after etching (ZH), 3) zirconia specimens after airborne particle abrasion and simultaneous etching (HSZ), 4) zirconia specimens coated with a layer of a Fluorapatite-Leucite glaze (GZ), 5) GZ specimens with additional acid etching (HGZ), 6) zirconia specimens coated with a layer of salt glaze (SGZ) and 7) SGZ specimens after etching with 2% HCl (HSGZ). Composite cylinders were bonded to airborne-particle-abraded surfaces of ZirkonZahn specimens with Panavia F2 resin luting agent. Failure modes were examined under 30 × magnification and the effect of surface treatments was analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). SZ and HSZ groups had the highest and GZ and SGZ groups had the lowest mean shear bond strengths among all groups. Mean shear bond strengths were significantly decreased by applying a glaze layer on zirconia surfaces in GZ and SGZ groups. However, bond strengths were improved after etching process. Airborne particle abrasion resulted in higher shear bond strengths compared to etching treatment. Modes of failure varied among different groups. Finally, it is concluded that micromechanical adhesion was a more effective mechanism than chemical adhesion and airborne particle abrasion significantly increased mean shear bond strengths compared with another surface treatments. - Highlights: • Understanding the dominant mechanism of bonding

  13. Pt, Re and Pt-Re incorporation in sulfated zirconia as catalysts for n-pentane isomerization

    International Nuclear Information System (INIS)

    Aboul-Gheit, A.K.; El-Desouki, D.S.; Abdel-Hamid, S.M.; Ghoneim, S.A.; Ibrahim, A.H.; Gad, F.K.; Abdel-Aleem, G.M.

    2010-01-01

    Two groups of modified Sulfated Zirconia (S Z) catalysts were prepared by the sol-gel method. The first group was modified by four different concentrations of Pt metal (0.15, 0.30, 0.45 and 0.60 wt %), whereas the second group contained Pt-Re combinations on SZ. All the prepared catalysts were characterized by XRD, TPR, TEM, TGA, IR spectroscopy as well as surface properties using the BET method. The catalytic activity of the catalysts was examined for the hydro isomerization of n-pentane to iso-pentane. The catalytic activity was found to increase with increasing Pt concentration in the mono metallic catalysts. The combination of Re ion with Pt on SZ results in significant changes in the characters and activities of the catalysts. The 0.45 wt % Pt + 0.15 wt % Re/SZ catalyst exhibited the highest selective compared to other metal ratios investigated

  14. Kinetic Monte Carlo Simulation of Oxygen and Cation Diffusion in Yttria-Stabilized Zirconia

    Science.gov (United States)

    Good, Brian

    2011-01-01

    Yttria-stabilized zirconia (YSZ) is of interest to the aerospace community, notably for its application as a thermal barrier coating for turbine engine components. In such an application, diffusion of both oxygen ions and cations is of concern. Oxygen diffusion can lead to deterioration of a coated part, and often necessitates an environmental barrier coating. Cation diffusion in YSZ is much slower than oxygen diffusion. However, such diffusion is a mechanism by which creep takes place, potentially affecting the mechanical integrity and phase stability of the coating. In other applications, the high oxygen diffusivity of YSZ is useful, and makes the material of interest for use as a solid-state electrolyte in fuel cells. The kinetic Monte Carlo (kMC) method offers a number of advantages compared with the more widely known molecular dynamics simulation method. In particular, kMC is much more efficient for the study of processes, such as diffusion, that involve infrequent events. We describe the results of kinetic Monte Carlo computer simulations of oxygen and cation diffusion in YSZ. Using diffusive energy barriers from ab initio calculations and from the literature, we present results on the temperature dependence of oxygen and cation diffusivity, and on the dependence of the diffusivities on yttria concentration and oxygen sublattice vacancy concentration. We also present results of the effect on diffusivity of oxygen vacancies in the vicinity of the barrier cations that determine the oxygen diffusion energy barriers.

  15. Style-based classification of Chinese ink and wash paintings

    Science.gov (United States)

    Sheng, Jiachuan; Jiang, Jianmin

    2013-09-01

    Following the fact that a large collection of ink and wash paintings (IWP) is being digitized and made available on the Internet, their automated content description, analysis, and management are attracting attention across research communities. While existing research in relevant areas is primarily focused on image processing approaches, a style-based algorithm is proposed to classify IWPs automatically by their authors. As IWPs do not have colors or even tones, the proposed algorithm applies edge detection to locate the local region and detect painting strokes to enable histogram-based feature extraction and capture of important cues to reflect the styles of different artists. Such features are then applied to drive a number of neural networks in parallel to complete the classification, and an information entropy balanced fusion is proposed to make an integrated decision for the multiple neural network classification results in which the entropy is used as a pointer to combine the global and local features. Evaluations via experiments support that the proposed algorithm achieves good performances, providing excellent potential for computerized analysis and management of IWPs.

  16. Expression of the p16{sup INK4a} tumor suppressor gene in rodent lung tumors

    Energy Technology Data Exchange (ETDEWEB)

    Swafford, D.S.; Tesfaigzi, J.; Belinsky, S.A.

    1995-12-01

    Aberrations on the short arm of chromosome 9 are among the earliest genetic changes in human cancer. p16{sup INK4a} is a candidate tumor suppressor gene that lies within human 9p21, a chromosome region associated with frequent loss of heterozygosity in human lung tumors. The p16{sup INK4a} protein functions as an inhibitor of cyclin D{sub 1}-dependent kinases that phosphorylate the retinoblastoma (Rb) tumor suppressor gene product enabling cell-cycle progression. Thus, overexpression of cyclin D{sub 1}, mutation of cyclin-dependent kinase genes, or loss of p16{sup INK4a} function, can all result in functional inactivation of Rb. Inactivation of Rb by mutation or deletion can result in an increase in p16{sup INK4a} transcription, suggesting that an increased p16{sup INK4a} expression in a tumor cell signals dysfunction of the pathway. The p16{sup (INK4a)} gene, unlike some tumor suppressor genes, is rarely inactivated by mutation. Instead, the expression of this gene is suppressed in some human cancers by hypermethylation of the CpG island within the first exon or by homozygous deletion: 686. Chromosome losses have been observed at 9p21 syntenic loci in tumors of the mouse and rat, two species often used as animal models for pulmonary carcinogenesis. Expression of p16{sup INK4a} is lost in some mouse tumor cell lines, often due to homozygous deletion. These observations indicate that p16{sup INK4a} dysfunction may play a role in the development of neoplasia in rodents as well as humans. The purpose of the current investigation was to define the extent to which p16{sup INK4a} dysfunction contributes to the development of rodent lung tumors and to determine the mechanism of inactivation of the gene. There is no evidence to suggest a loss of function of the p16{sup INK4a} tumor suppressor gene in these primary murine lung tumors by mutation, deletion, or methylation.

  17. Analysis of the zirconia structure by `ab initio` and Rietveld methods; Analise da estrutura da zirconia por metodos `Ab initio` e de Rietveld

    Energy Technology Data Exchange (ETDEWEB)

    Bechepeche, A.P.; Nasar, R.S.; Longo, E. [Sao Carlos Univ., SP (Brazil). Dept. de Quimica; Treu Junior, O.; Varela, J.A. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica

    1995-12-31

    The zirconia was doped with 0,113 mol of Mg O e 0,005 mol of Ti O{sub 2}, and it was calcined in 1550{sup d}eg C and it was analyzed by XRD. The results shows that pure zirconia contains 96,19% of monoclinic phase and 3,18% of cubic. However, the doping magnesia stabilizes the zirconia in 17,24 of monoclinic; 29,63 of tetragonal and 53,13% of cubic phase. The addition of titanium in zirconia gives 25,85% of tetragonal phase and 37,66% of cubic, and this shows the no stabilizing action of this transition metal. By the other side, the results with ab-initio calculating shows the same tendency resulting in the next values of total energy: pure zirconia - monoclinic -11.316,86ua; tetragonal -8742,09 ua and cubic -8742,80 ua and Zr O{sub 2} Ti O{sub 2} system - monoclinic -9463,02 ua, tetragonal -9459,39 ua and cubic -9459,97 ua (author) 3 figs., 2 tabs.

  18. Properties and clinical application of zirconia bioceramics in medicine

    Directory of Open Access Journals (Sweden)

    Čedomir Oblak

    2014-01-01

    Full Text Available Background: A group of inorganic non-metal biomaterials, that are commonly used in clinical medicine to replace or repair tissues, can be classified as a bioceramics. This group includes bioactive glasses, glass-ceramics, hydroxy-apatite and some other calcium phosphates. In addition, some bio-inert engineering ceramics materials have become increasingly utilised, aluminum oxide, zirconium oxide and their composites being the most popular. With the developement of yttria stabilized tetragonal zirconium oxide ceramics (Y-TZP medical community received a high strength biomaterial that is currently a material of choice for the manufacturing of medical devices. Y-TZP ceramics is becoming also increasingly used in dental medicine, where frameworks are manufactured by the use of computer-assisted technology.Conclusions: The article describes the basic properties of zirconia oxide ceramics important for the use in clinical medicine; high strength and fracture toughness, biocompatibility and negligible radiation. The ageing issue of this particular material, which is attributable to the thermo-dynamical instability of tetragonal zirconium oxide in hydrothermal conditions, is also discussed. When exposed to an aqueous environment over long periods of time, the surface of the Y-TZP ceramic will start transforming spontaneously into the monoclinic structure. The mechanism leading to the t-m transformation is temperature-dependent and is accompanied by extensive micro-cracking, which ultimately leads to strength degradation. The degradation might influence the clinical success rate of medical devices and therefore Y-TZP femoral heads are no longer made of pure zirconium oxide. Composites of zirconium and aluminium oxides are used instead, that are currently the strongest ceramic materials used in clinical medicine. In this work the clinical application of zirconia oxide ceramics in dental medicine is also presented. Conventional porcelain fused to metal

  19. The nature of ancient Egyptian copper-containing carbon inks is revealed by synchrotron radiation based X-ray microscopy

    OpenAIRE

    Christiansen , Thomas; Cotte , Marine; Loredo-Portales , René; Lindelof , Poul ,; Mortensen , Kell; Ryholt , Kim; Larsen , Sine

    2017-01-01

    International audience; For the first time it is shown that carbon black inks on ancient Egyptian papyri from different time periods and geographical regions contain copper. The inks have been investigated using synchrotron-based micro X-ray fluorescence (XRF) and micro X-ray absorption near-edge structure spectroscopy (XANES) at the European Synchrotron Radiation Facility (ESRF). The composition of the copper-containing carbon inks showed no significant differences that could be related to t...

  20. Producing fluorescent digital printing ink: Investigating the effect of type and amount of coumarin derivative dyes on the quality of ink

    Energy Technology Data Exchange (ETDEWEB)

    Ataeefard, Maryam, E-mail: ataeefard-m@icrc.ac.ir [Department of Printing Science and Technology, Institute for Color Science and Technology, P.O. Box 16765-654, Tehran (Iran, Islamic Republic of); Nourmohammadian, Farahnaz, E-mail: nour@icrc.ac.ir [Centre of Excellence for Colour Science and Technology, Institute for Colour Science and Technology, P.O. Box 16765-654, Tehran (Iran, Islamic Republic of); Department of Organic Colorants, Institute for Colour Science and Technology, P.O. Box 16765-654, Tehran (Iran, Islamic Republic of)

    2015-11-15

    The aim of this work is to produce a composite powder as a fluorescent ink for digital electrophotographic printing. Three benzoxazolyl and benzimidazolyl coumarin derivative dyes are used as fluorescent dyes that are incorporated into poly (styrene-co-a crylic acid) using eco-friendly emulsion aggregation (EA) approaches in several amounts with final application of fluorescent laser printing ink called toner. Fluorescence and daylight spectrophotometry is used for investigating the emission and reflectance properties of fluorescent toner. It was found that the relations between emission of fluorescent toners and the amount of dyes are non-linear. Particle size analysis, scanning electron microscopy, differential scanning calorimeter and thermal gravimetric analysis were used to study the size, shape, morphology and thermal properties of fluorescent toner particles. Results verify that the polarity of the dyes and their compatibility with the environment could affect the shape of the fluorescent toner. In addition, the results show that the fluorescent toner produced by the EA method has appropriate characteristics comparing to an industrial toner. - Highlights: Fluorescent digital printing ink produced via emulsion aggregation technique. Fluorescent ink for produced for electrophotographic printing. The relations between fluorescent emission and the amount of dyes are non-linear. Different dyes, show different behavior.

  1. Producing fluorescent digital printing ink: Investigating the effect of type and amount of coumarin derivative dyes on the quality of ink

    International Nuclear Information System (INIS)

    Ataeefard, Maryam; Nourmohammadian, Farahnaz

    2015-01-01

    The aim of this work is to produce a composite powder as a fluorescent ink for digital electrophotographic printing. Three benzoxazolyl and benzimidazolyl coumarin derivative dyes are used as fluorescent dyes that are incorporated into poly (styrene-co-a crylic acid) using eco-friendly emulsion aggregation (EA) approaches in several amounts with final application of fluorescent laser printing ink called toner. Fluorescence and daylight spectrophotometry is used for investigating the emission and reflectance properties of fluorescent toner. It was found that the relations between emission of fluorescent toners and the amount of dyes are non-linear. Particle size analysis, scanning electron microscopy, differential scanning calorimeter and thermal gravimetric analysis were used to study the size, shape, morphology and thermal properties of fluorescent toner particles. Results verify that the polarity of the dyes and their compatibility with the environment could affect the shape of the fluorescent toner. In addition, the results show that the fluorescent toner produced by the EA method has appropriate characteristics comparing to an industrial toner. - Highlights: Fluorescent digital printing ink produced via emulsion aggregation technique. Fluorescent ink for produced for electrophotographic printing. The relations between fluorescent emission and the amount of dyes are non-linear. Different dyes, show different behavior

  2. Plasmachemical synthesis of nanopowders of yttria and zirconia from dispersed water-salt-organic mixtures

    Science.gov (United States)

    Novoselov, Ivan; Karengin, Alexander; Shamanin, Igor; Alyukov, Evgeny; Gusev, Alexander

    2018-03-01

    Article represents results on theoretical and experimental research of yttria and zirconia plasmachemical synthesis in air plasma from water-salt-organic mixtures "yttrium nitrate-water-acetone" and "zirconyl nitrate-water-acetone". On the basis of thermotechnical calculations the influence of organic component on lower heat value and adiabatic combustion temperature of water-salt-organic mixtures as well as compositions of mixtures providing their energy-efficient plasma treatment were determined. The calculations found the influence of mass fraction and temperature of air plasma supporting gas on the composition of plasma treatment products. It was determined the conditions providing yttria and zirconia plasmachemical synthesis in air plasma. During experiments it was b eing carried out the plasmachemical synthesis of yttria and zirconia powders in air plasma flow from water -salt-organic mixtures. Analysis of the results for obtained powders (scanning electron microscopy, X-ray diffraction analysis, BET analysis) confirm nanostructure of yttria and zirconia.

  3. Ion-exchange behaviour of hydrous zirconia in mixed solvents: capacity and kinetics of exchange

    International Nuclear Information System (INIS)

    Misak, N.Z.; Ghoneimy, H.F.

    1982-01-01

    The capacity of the Li + form of hydrous zirconia for Na + and Cs + increases in the presence of methanol. This may be due to the greater stability of Li + in methanol/water than in pure water and to dehydration of Na + and Cs + and their stronger interaction with the exchange sites, which may facilitate their replacing Li + . The ion-exchange capacity of zirconia for NO 3 - , Cl - and Br - is almost the same in aqueous solution and is not affected by addition of up to 90% (v/v) methanol, which probably shows that these anions are electrostatically bound in zirconia without specific interactions. The internal diffusion coefficients of the Na + /H + and Cl - /OH - systems decrease in the presence of alcohol: the decrease is highest with methanol and similar for ethanol and propan-2-ol. This is discussed in the light of ion solvation and alcohol penetration inside zirconia. (author)

  4. Fabrication and properties of yttria, ceria doped zirconia-aluminia ceramic composites

    International Nuclear Information System (INIS)

    Lyubushkin, R.A.; Ivanov, O.N.; Chuev, V.P.; Buzov, A.A.

    2011-01-01

    At present, zirconia-based ceramics are gaining popularity in dentistry, particularly in fixed prosthodontics. clinically, it is important that ceramic restorations reproduce the translucency and color of natural teeth. Zirconia based ceramics is a high performance material with excellent biocompatibility and mechanical properties, which suggest its suitability for posterior fixed partial dentures. Y 2 O 3 -stabilized tetragonal zirconia polycrystalline (YTZ/Al 2 O 3 ) and CeO 2 -stabilized tetragonal zirconia polycrystalline (CZA) ceramics with high-performance were prepared for dental application by use the wet chemical route, consolidated by cold isostatic pressing, and two-step sintering method. Physical and mechanical properties test results show that the bending strength, fracture toughness, and the density of full sintered ceramics suggest that the material is relatively suitable for dental restoration.

  5. Zirconia crowns for rehabilitation of decayed primary incisors: an esthetic alternative.

    Science.gov (United States)

    Ashima, G; Sarabjot, K Bhatia; Gauba, K; Mittal, H C

    2014-01-01

    Esthetic management of extensively decayed primary maxillary anterior teeth requiring full coronal coverage restoration is usually challenging to the pediatric dentists especially in very young children. Many esthetic options have been tried over the years each having its own advantages, disadvantages and associated technical, functional or esthetic limitations. Zirconia crowns have provided a treatment alternative to address the esthetic concerns and ease of placement of extra-coronal restorations on primary anterior teeth. The present article presents a case where grossly decayed maxillary primary incisors were restored esthetically and functionally with ready made zirconia crowns (ZIRKIZ, HASS Corp; Korea). After endodontic treatment the decayed teeth were restored with zirconia crowns. Over a 30 months period, the crowns have demonstrated good retention and esthetic results. Dealing with esthetic needs in children with extensive loss of tooth structure, using Zirconia crowns would be practical and successful. The treatment described is simple and effective and represents a promising alternative for rehabilitation of decayed primary teeth.

  6. Immunohistochemical study of p16 INK4A and survivin expressions in cervical squamous neoplasm

    Directory of Open Access Journals (Sweden)

    Tan Geok

    2010-01-01

    Full Text Available Introduction:Cervical cancer is the second most common cancer affecting Malaysian women. Despite the implementation of pap smear screening, many women are still diagnosed only in the advanced stage of cervical cancer. This could partly be due to failure of detection of its precursor lesions; hence the need to search for novel biomarkers to assist in the screening and diagnosis of cervical neoplasia. This study aims to determine the expression of p16INK4A and survivin as possible predictive biomarkers in cervical squamous neoplasm. Material and Methods: This is a retrospective study on 201 cases of cervical neoplasm comprising of 129 cervical intraepithelial neoplasia (CIN and 72 squamous cell carcinoma (SCC. All samples were evaluated by two independent observers using p16INK4A and survivin monoclonal antibodies. The p16 INK4A expression was graded as negative, focal and diffuse positivity. The intensity for survivin expression was graded as weak, moderate and intense. Results: It is seen that p16 INK4A expression in CIN 1, CIN 2 and CIN 3 were 25.4%, 42.9% and 95.9% respectively. Majority of SCC (98.6% showed p16 INK4A expression. Survivin expressions in CIN 1, CIN 2, CIN 3 and SCC were 56.7%, 33.4%, 87.5% and 98.6%. There was a linear relationship between increasing grade of CIN and p16 INK4A expressions. Conclusion: Our study showed that p16 INK4A expressions correlate well with the increasing grade of CIN. Although survivin does not correlate well to the increasing grade of CIN, it could be useful in differentiating CIN 3 from SCC.

  7. Expression of p16(INK4A) gene in human pituitary tumours.

    Science.gov (United States)

    Machiavelli, Gloria; Cotignola, Javier; Danilowicz, Karina; Carbonara, Carolina; Paes de Lima, Andrea; Basso, Armando; Bruno, Oscar Domingo; Szijan, Irene

    2008-01-01

    Pituitary adenomas comprise 10-15% of primary intracranial tumours but the mechanisms leading to tumour development are yet to be clearly established. The retinoblastoma pathway, which regulates the progression through the cell cycle, is often deregulated in different types of tumours. We studied the cyclin-dependent kinase inhibitor p16(INK4A) gene expression at mRNA level in human pituitary adenomas. Forty-six tumour specimens of different subtypes, 21 clinically non-functioning, 12 growth hormone-secreting, 6 prolactin-secreting, 6 adrenocorticotropin-secreting, and 1 thyrotropin-secreting tumours were studied. All clinically non-functioning and most of the hormone-secreting tumours were macroadenomas (38/46). The RT-PCR assay and electrophoresis of the PCR-products showed that p16(INK4A) mRNA was undetectable in: 62% of non-functioning, 8% of growth hormone-secreting, 17% of prolactin-secreting and 17% of adrenocorticotropin-secreting adenomas. Forty percent of all macroadenomas and 25% of microadenomas had negative p16(INK4A) mRNA, the latter results suggest that the absence of p16(INK4A) product might be an early event in tumours with no expression of this suppressor gene. Within the non-functioning adenomas 63% were "null cell" and 37% were positive for some hormone, both subgroups showed similar percentage of cases with absence of p16(INK4A) mRNA. Our results show that clinically non-functioning macroadenomas have impaired p16(INK4A) expression in a clearly higher proportion than any other pituitary tumour subtype investigated. Other regulatory pathways may be implicated in the development of tumours with positive p16(INK4A) expression.

  8. Systematic study of terahertz time-domain spectra of historically informed black inks.

    Science.gov (United States)

    Bardon, Tiphaine; May, Robert K; Taday, Philip F; Strlič, Matija

    2013-09-07

    The potential of terahertz-time domain spectroscopy (THz-TDS) as a diagnostic tool for studies of inks in historical documents is investigated in this paper. Transmission mode THz-TDS was performed on historically informed model writing and drawing inks. Carbon black, bistre and sepia inks show featureless spectra between 5 and 75 cm(-1) (0.15-2.25 THz); however, their analysis still provided useful information on the interaction of terahertz radiation with amorphous materials. On the other hand, THz-TDS can be used to distinguish different iron gall inks with respect to the amount of iron(II) sulfate contained, as sharp spectral features are observed for inks containing different ratios of iron(II) sulfate to tannic or gallic acid. Additionally, copper sulfate was found to modify the structure of iron(II) precipitate. Furthermore, Principal Component Analysis (PCA) applied to THz-TDS spectra, highlights changes in iron gall inks during thermal degradation, during which a decrease in the sharp spectral bands associated with iron(II) sulfate is observed. ATR-FTIR spectroscopy combined with THz-TDS of dynamically heated ink samples indicate that this phenomenon is due to dehydration of iron(II) sulfate heptahydrate. While this research demonstrates the potential of THz-TDS to improve monitoring of the chemical state of historical documents, the outcomes go beyond the heritage field, as it also helps to develop the theoretical knowledge on interactions between terahertz radiation and matter, particularly in studies of long-range symmetry (polymorphism) in complex molecular structures and the role played by the surrounding matrix, and also indicates the potential of THz-TDS for the optimization of contrast in terahertz imaging.

  9. Role of the Digestive Gland in Ink Production in Four Species of Sea Hares: An Ultrastructural Comparison

    Directory of Open Access Journals (Sweden)

    Jeffrey S. Prince

    2013-01-01

    Full Text Available The ultrastructure of the digestive gland of several sea hare species that produce different colored ink (Aplysia californica produces purple ink, A. juliana white ink, A. parvula both white and purple ink, while Dolabrifera dolabrifera produces no ink at all was compared to determine the digestive gland’s role in the diet-derived ink production process. Rhodoplast digestive cells and their digestive vacuoles, the site of digestion of red algal chloroplast (i.e., rhodoplast in A. californica, were present and had a similar ultrastructure in all four species. Rhodoplast digestive cell vacuoles either contained a whole rhodoplast or fragments of one or were empty. These results suggest that the inability to produce colored ink in some sea hare species is not due to either an absence of appropriate digestive machinery, that is, rhodoplast digestive cells, or an apparent failure of rhodoplast digestive cells to function. These results also propose that the digestive gland structure described herein occurred early in sea hare evolution, at least in the common ancestor to the genera Aplysia and Dolabrifera. Our data, however, do not support the hypothesis that the loss of purple inking is a synapomorphy of the white-ink-producing subgenus Aplysia.

  10. Sol-gel derived bioactive coating on zirconia: Effect on flexural strength and cell proliferation.

    Science.gov (United States)

    Shahramian, Khalil; Leminen, Heidi; Meretoja, Ville; Linderbäck, Paula; Kangasniemi, Ilkka; Lassila, Lippo; Abdulmajeed, Aous; Närhi, Timo

    2017-11-01

    The purpose of this study was to evaluate the effect of sol-gel derived bioactive coatings on the biaxial flexural strength and fibroblast proliferation of zirconia, aimed to be used as an implant abutment material. Yttrium stabilized zirconia disc-shaped specimens were cut, ground, sintered, and finally cleansed ultrasonically in each of acetone and ethanol for 5 minutes. Three experimental groups (n = 15) were fabricated, zirconia with sol-gel derived titania (TiO 2 ) coating, zirconia with sol-gel derived zirconia (ZrO 2 ) coating, and non-coated zirconia as a control. The surfaces of the specimens were analyzed through images taken using a scanning electron microscope (SEM), and a non-contact tapping mode atomic force microscope (AFM) was used to record the surface topography and roughness of the coated specimens. Biaxial flexural strength values were determined using the piston-on-three ball technique. Human gingival fibroblast proliferation on the surface of the specimens was evaluated using AlamarBlue assay™. Data were analyzed using a one-way analysis of variance (ANOVA) followed by Tukey's post-hoc test. Additionally, the biaxial flexural strength data was also statistically analyzed with the Weibull distribution. The biaxial flexural strength of zirconia specimens was unaffected (p > 0.05). Weibull modulus of TiO 2 coated and ZrO 2 coated groups (5.7 and 5.4, respectively) were lower than the control (8.0). Specimens coated with ZrO 2 showed significantly lower fibroblast proliferation compared to other groups (p sol-gel derived coatings have no influence on the flexural strength of zirconia. ZrO 2 coated specimens showed significantly lower cell proliferation after 12 days than TiO 2 coated or non-coated control. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2401-2407, 2017. © 2016 Wiley Periodicals, Inc.

  11. Effect of coping thickness and background type on the masking ability of a zirconia ceramic.

    Science.gov (United States)

    Tabatabaian, Farhad; Taghizade, Fateme; Namdari, Mahshid

    2018-01-01

    The masking ability of zirconia ceramics as copings is unclear. The purpose of this in vitro study was to evaluate the effect of coping thickness and background type on the masking ability of a zirconia ceramic and to determine zirconia coping thickness cut offs for masking the backgrounds investigated. Thirty zirconia disks in 3 thickness groups of 0.4, 0.6, and 0.8 mm were placed on 9 backgrounds to measure CIELab color attributes using a spectrophotometer. The backgrounds included A1, A2, and A3.5 shade composite resin, A3 shade zirconia, nickel-chromium alloy, nonprecious gold-colored alloy, amalgam, black, and white. ΔE values were measured to determine color differences between the specimens on the A2 shade composite resin background and the same specimens on the other backgrounds. The color change (ΔE) values were compared with threshold values for acceptability (ΔE=5.5) and perceptibility (ΔE=2.6). Repeated measures ANOVA, the Bonferroni test, and 1-sample t tests were used to analyze data (α=.05). Mean ΔE values ranged between 1.44 and 7.88. The zirconia coping thickness, the background type, and their interaction affected the CIELab and ΔE values (Pmasking, the minimum thickness of a zirconia coping should be 0.4 mm for A1 and A3.5 shade composite resin, A3 shade zirconia, and nonprecious gold-colored alloy, 0.6 mm for amalgam, and 0.8 mm for nickel-chromium alloy. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  12. Iron on mixed zirconia-titania substrate F-T catalyst

    International Nuclear Information System (INIS)

    Dyer, P.N.; Nordquist, A.F.; Pierantozzi, R.

    1988-01-01

    This patent deals with a Fischer-Tropsch catalyst comprising iron co-deposited with or deposited on particles comprising a mixture of zirconia and titania, preferably formed by co-precipitation of compounds convertible to zirconia and titania, such as zirconium and titanium alkoxide. The invention also comprises the method of making this catalyst and an improved Fischer-Tropsch reaction process in which the catalyst is utilized

  13. Investigation of the evaporation process conditions on the optical constants of zirconia films

    International Nuclear Information System (INIS)

    Dobrowolski, J.A.; Grant, P.D.; Simpson, R.; Waldorf, A.

    1989-01-01

    Deposition parameters required for producing zirconia films for use in optical multilayer systems by electron-beam gun evaporation of zirconia and zirconium starting materials were investigated. The optical constants were determined as a function of distance, partial pressure of oxygen, and angle of incidence. The direct and reactive evaporation processes yielded ZrO 2 films with refractive indices of 2.08 and 2.14, respectively, for vapor incident on the substrate at normal incidence

  14. Evaluation of torque loss value of MAD/MAM zirconia abutments with prefabricated titanium abutments

    OpenAIRE

    Marzieh Alikhasi; Roshanak Baghaie; Nasim khosronejad

    2013-01-01

    Background and Aims: In response to esthetic demand of patients, ceramic abutments have been developed. Despite esthetic of zirconia abutments, machining accuracy of these abutments has always been a question. Any misfit in the abutment-implant interface connection can lead to detorque and screw loosening. The aim of this study was to compare torque loss value of manually aided design/manually aided manufacture (MAD/MAM) zirconia abutments with prefabricated titanium abutments. Materials and ...

  15. Influence of starting precursors and synthesis methods on the physiochemical properties of zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Gaydhankar, T.R., E-mail: tr.gaydhankar@ncl.res.in [Catalysis Division, National Chemical Laboratory, Pune 411008 (India); Jha, R.K. [Catalysis Division, National Chemical Laboratory, Pune 411008 (India); Nikalje, M.D. [Department of Chemistry, University of Pune, Pune 411 007 (India); Waghmare, K.J. [Catalysis Division, National Chemical Laboratory, Pune 411008 (India)

    2014-07-01

    Graphical abstract: Crystallite size of tetragonal phase of the zirconia samples prepared using different synthesis parameters and precursors as a function of calcination temperature. Surface area values of the zirconia samples calcined at 500 and 700 °C are in given brackets. - Highlights: • Zirconia prepared with modified sol–gel method is less stable compared with zirconia prepared by precipitation method. • Optimized synthesis conditions shifted the glow exotherm to higher temperature range indicating better thermal stability. • Tetragonal-zirconia could be synthesized in cost-effective manner using zirconium oxy-nitrate. • In our studies no co-relation between the surface area and crystallite size was observed. - Abstract: Under identical and judiciously pre-optimized synthesis conditions, the influence of different combinations of zirconium sources and/or post treatment conditions on structural properties, thermal stability, phase composition and morphology of zirconia has been investigated. High surface area tetragonal zirconia could be synthesized in a cost-effective manner from 1 M solution of zirconium oxy-nitrate at pH 11 using aqueous ammonia solution as a precipitant when calcined at 400 °C for 3 h. Irrespective of the preparation method, pH and starting precursor, zirconia samples prepared without digestion contained dominant monoclinic phase with some traces of tetragonal phase when calcined at 700 °C. Even though there is linear decrease in surface area with increase in the crystallite size for each sample as a function of calcination temperature, no co-relation between the surface area and crystallite size could be achieved. SEM images show agglomerated and irregular shape particles between 10 to 20 μm.

  16. Ultraviolet and electron-beam curing of printing inks. January 1980-August 1987 (Citations from World Surface Coatings Abstracts). Report for January 1980-August 1987

    International Nuclear Information System (INIS)

    1989-08-01

    This bibliography contains citations concerning methods, techniques, and applications for the ultraviolet and electron-beam curing of printing inks. Topics include ink compositions, curing methods and equipment, cured-ink evaluations, screen printing inks, photoinitiators, and ink binders. The pollution and safety problems, and future trends of UV- and E-beam-cured printing inks are considered. Applications in screen printing on polyethylene or polypropylene bottles, and decorative printing of glass are also examined. (This updated bibliography contains 237 citations, 63 of which are new entries to the previous edition.)

  17. Pressure induced phase transitions in ceramic compounds containing tetragonal zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Sparks, R.G.; Pfeiffer, G.; Paesler, M.A.

    1988-12-01

    Stabilized tetragonal zirconia compounds exhibit a transformation toughening process in which stress applied to the material induces a crystallographic phase transition. The phase transition is accompanied by a volume expansion in the stressed region thereby dissipating stress and increasing the fracture strength of the material. The hydrostatic component of the stress required to induce the phase transition can be investigated by the use of a high pressure technique in combination with Micro-Raman spectroscopy. The intensity of Raman lines characteristic for the crystallographic phases can be used to calculate the amount of material that has undergone the transition as a function of pressure. It was found that pressures on the order of 2-5 kBar were sufficient to produce an almost complete transition from the original tetragonal to the less dense monoclinic phase; while a further increase in pressure caused a gradual reversal of the transition back to the original tetragonal structure.

  18. Application of zirconia membranes as high-temperature PH sensors

    International Nuclear Information System (INIS)

    Neidrach, L.W.

    1983-01-01

    The zirconia pH sensor behaves much like the classical glass electrode, but it extends the range of measurement to much higher temperatures - about 300 0 vs 120 0 C. It also has virtues over the glass electrode at lower temperatures because of the absence of an ''alkaline error.'' Like the glass electrode, it is insensitive to changes in the redox potential of the environment and, in turn, it exerts no influence on the environment. Such sensors have been finding application in the direct measurement of the pH of geothermal brines, of water in nuclear reactors, and in high-temperature corrosion studies. The sensors can also be used as ''pseudoreference'' electrodes for the measurement of redox and corrosion potentials in high-temperature media

  19. Partially stabilized zirconia (PSZ) - what's in it for chemical engineers?

    International Nuclear Information System (INIS)

    Michelmore, A.G.

    1988-01-01

    Partial Stabilized Zirconia (PSZ) is a non-brittle ceramic material with virtually the same modulus of elasticity, Poisson's ratio, tensile strength, and co-efficient of thermal expansion as steel, coupled with low thermal conductivity, low electrical conductivity, high hardness, non-magnetic properties and high corrosion resistance. Uses are in a wide variety of applications such as automotive, computer, hot copper extrusion dies, delicate laboratory equipment, mining spigots and injection moulding gates for plastic. Applications previously thought to be impossible for ceramics such as in high thermal and/or mechanical shock situations are now possible with benefits such as longer life, reduced maintenance costs, less downtime, lower stock inventory and improved productivity. Examples given here include downhole pump check valves in the oil and gas industry, dry bearings in the mining industry and plungers for pumping tomato paste in the food processing industry. A brief comparison is made of other PSZs and Nilcra PSZ. 1 fig

  20. Short range investigation of sub-micron zirconia particles

    Energy Technology Data Exchange (ETDEWEB)

    Caracoche, M C; Martinez, J A [Departamento de Fisica, IFLP, Facultad de Ciencias Exactas, CICPBA, Universidad Nacional de La Plata (Argentina); Rivas, P C [IFLP-CONICET, Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata (Argentina); Bondioli, F; Cannillo, V [Dipartimento di Ingegniria dei Materiali e dell' Ambiente, Facolta di Ingegneria, Universita di Modena e Reggio Emilia (Italy); Ferrari, A M, E-mail: cristina@fisica.unlp.edu.a [Dipartimento di Scienza a Metodi dell' Ingegneria, Universita di Modena e Reggio Emilia (Italy)

    2009-05-01

    The Perturbed Angular Correlations technique was used to determine the configurations around Zirconium ions and their thermal behavior in non-aggregated sub-micron zirconia spherical particles. Three residues containing- Zr surroundings were determined for the non-crystalline starting particles, which were identified under the assumption of a certain chemical reactions sequence during synthesis. While the one made up mainly by hydroxyl groups was common to both samples, the two involving mainly organic residues were particle size dependent. Upon crystallization, both samples stabilized in the t'- and t- tetragonal forms and the Xc-cubic form but their amounts and temperatures of appearance were different. On heating, the structure of the smaller particles became gradually monoclinic achieving total degradation upon the subsequent cooling to RT.