Sample records for araldite


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    Full Text Available Flammability characteristics of araldite based composite mixed with inorganic hybrid flame retardant represent zinc borate - antimony trioxide as a surface layer(4mm thickness have been studied by thermal erosion test . Antimony trioxide was added to zinc borate with various amounts (10%,20% and 30% to forming a hybrid flame retardant for enhance the action of this material to react flame . The result composite material was exposed to a direct flame generated from Oxyacetylene torch (3000ºC with different flame exposure intervals (10,20mm, and studies the range of resistance of retardant material layer to the flames and protected the substrate. The optimum results were with large percentage from protective layer which is zinc borate-30% antimony trioxide and large exposed distance.

  2. Eletrodo compósito à base de grafite-araldite®: aplicações didáticas Graphite-araldite® composite electrode: didactic applications

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    Carolina Maria Fioramonti Calixto


    Full Text Available A composite electrode prepared by mixing a commercial epoxy resin Araldite® and graphite powder is proposed to be used in didactic experiments. The electrode is prepared by the students and applied in simple experiments to demonstrate the effect of the composite composition on the conductivity and the voltammetric response of the resulting electrode, as well as the response in relation to the scan rate dependence on mass transport. The possibility of using the composite electrode in quantitative analysis is also demonstrated.

  3. Morphology of the Kidney in the West African Caecilian, Geotrypetes seraphini (Amphibia, Gymnophiona, Caeciliidae)

    DEFF Research Database (Denmark)

    Møbjerg, Nadja; Jespersen, Åse; Wilkinson, M.


    This study deals with the morphology and ultrastructure of the mesonephros in adult caecilians of the species Geotrypetes seraphini. Based on serial sections in paraffin and araldite, nephrons are reconstructed and the cellular characteristics of different nephron segments described. The long and...

  4. S-HCEP——一种新的低成本合成绝缘子材料%Shed Hydrophobic Cycloaliphatic Epoxy (S-HCEP)- a New Cost-efficient Housing Material for Composite Insulators

    Institute of Scientific and Technical Information of China (English)


    Araldite S-HCEP, a new cost-efficient alternative housing material for composite insulators is briefly presented. Main topics of this paper are the results of two new studies on this material:①UV-weathering resistance in terms of hydrophobicity, roughness increase, surface resistance and flexibility. ②Leakage current behavior under salt fog conditions in comparison to other materials.

  5. Development of graphite-polymer composites as electrode materials

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    Carolina Maria Fioramonti Calixto


    Full Text Available Graphite powder was mixed to polyurethane, silicon rubber and Araldite® (epoxy in order to prepare composite materials to be used in the preparation of electrodes. Results showed that voltammetric response could be obtained when at least 50% of graphite (w.w-1 is present in the material. SEM and thermogravimetry were also used in the characterization of the composites.

  6. Thermal Characterization and Optimization of the Pixel Module Support Structure for the Phase-1 Upgrade of the CMS Pixel Detector

    CERN Document Server

    Rauch, Max Philip


    article/pii/0011747168900570, accessed on 7/21/2015.[38] Torayca, T300 Data Sheet,, accessedon 8/12/2015.[39] Araldite, Araldite Standard,, accessed on 6/19/2015.[40] S. Streuli, Paul-Scherrer-Institut (Villigen, Switzerland), private communication.[41] KERAFOL, Keratherm Thermal Grease: KP 98,, accessed on 6/19/2015.[42] K. Klein, 1. Physikalisches Institut B, RWTH Aachen, private communication.[43] COMSOL Multiphysics R Modeling Software,, accessed on 7/28/2015.[44] COMSOL Multiphysics R Heat Transfer Software,, accessed on 28.7.2015.[45] Picture taken from, accessed on 7/28/2015.[46] Mitsubishi Chemical, Dialead, K13D2U,, accessed on 7/29/2015.[47] Tenc...

  7. Testing temperature on interfacial shear strength measurements of epoxy resins at different mixing ratios

    DEFF Research Database (Denmark)

    Petersen, Helga Nørgaard; Thomason, James L.; Minty, Ross;


    The interfacial properties as Interfacial Shear Stress (IFSS) in fibre reinforced polymers are essential for further understanding of the mechanical properties of the composite. In this work a single fibre testing method is used in combination with an epoxy matrix made from Araldite 506 epoxy resin...... and triethylenetetramine (TETA) hardener. The IFSS was measured by a microbond test developed for a Thermal Mechanical Analyzer. The preliminary results indicate that IFSS has an inverse dependency of both testing temperature and the mixing ratio of hardener and epoxy resin. Especially interesting was the decreasing...

  8. Epoxy Pipelining Composition and Method of Manufacture. (United States)


    resin such as DGEBA (the diglycidyl ether of bisphenol A; see infra page 38) 16 and/or DGEBF (the diglycidyl ether of bisphenol F; see infra page 38...acid and 1,2 DCH, 20 about 22.4 mole % of the benzyl alcohol (i.e. the exemplary reactive diluent), and about 21 6.26 mole % of the DGEBA wherein x = 0...of the part A epoxy resin 5 ( DGEBA : Epon° 828, and/or Araldite XU Bis F GY° 281) containing optional 6 pigments such as Titanium Oxide (TiO 2 R-960

  9. Formation and Properties of Polymers Used in Organic Matrix Composites. (United States)


    Reference DGEBA /MDA4 -9( 170 0.76 0.45 11 Epozy/HHPAb 20(?) 250(’) 0.62 0.35 11 Epoxy glass laminate 62 127 0.84 0.71 12 Epon 828/DDSe lif 189 1.21 0.74...13 DGEBA /amined -10 115(7) 0.62 0.41 3 Epon 828/PACM-20’ -19 166 0.34 0.19 this work Diglycidyl ether of Bisphenol A (Araldite F (CY 205) Ciba Geigy

  10. Optical self-sensing of impact damage in composites using E-glass cloth (United States)

    Rauf, A.; Hand, R. J.; Hayes, S. A.


    Self-sensing of damage in composites employs the reinforcing fibres as the sensing element, obviating the need for addition of sensing elements to the system. Optical self-sensing systems in the past have relied on the use of low refractive index resins in order to work, preventing the use of commercial laminating resins. In this study a commercial laminating resin (Araldite LY5052/Aradur HY5052) is modified with propylene carbonate, a commercial reactive diluent, to reduce the resin’s refractive index. It is shown that this system is capable of identifying and locating an impact and quantifying the extent of damage within a composite.

  11. Identification of parameters of cohesive elements for modeling of adhesively bonded joints of epoxy composites

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    Kottner R.


    Full Text Available Adhesively bonded joints can be numerically simulated using the cohesive crack model. The critical strain energy release rate and the critical opening displacement are the parameters which must be known when cohesive elements in MSC.Marc software are used. In this work, the parameters of two industrial adhesives Hunstman Araldite 2021 and Gurit Spabond 345 for bonding of epoxy composites are identified. Double Cantilever Beam (DCB and End Notched Flexure (ENF test data were used for the identification. The critical opening displacements were identified using an optimization algorithm where the tests and their numerical simulations were compared.

  12. Construction of an amperometric ascorbate biosensor using epoxy resin membrane bound Lagenaria siceraria fruit ascorbate oxidase. (United States)

    Pundir, C S; Chauhan, Nidhi; Jyoti


    Ascorbate oxidase purified from Lagenaria siceraria fruit was immobilized onto epoxy resin "Araldite" membrane with 79.4% retention of initial activity of free enzyme. The biosensor showed optimum response within 15s at pH 5.8 and 35°C, which was directly proportional to ascorbate concentration ranging from 1-100μM. There was a good correlation (R(2) = 0.99) between serum ascorbic acid values by standard enzymic colorimetric method and the present method. The enzyme electrode was used for 200 times without considerable loss of activity during the span of 90 days when stored at 4°C.

  13. Preventing, monitoring and curing the ageing in the LHCb Outer Tracker

    CERN Document Server

    Visser, Erwin Lourens; Bethlem, H L


    The modules of the LHCb Outer Tracker have shown to suffer from gain loss under irradiation at moderate intensities, a process known as ageing. The plastifier in the glue with which the detector modules were constructed, Araldite AY103-1, has been shown to be the culprit. In this thesis this is confirmed by irradiating a module constructed with Araldite AY105-1, which does not contain the harmful plastifier. Several methods to prevent and repair the gain loss exist. One preventive measure is the addition of oxygen. However, because of its electronegative nature, oxygen can capture some of the drifting electrons, thereby lowering the gain of the OT. Simulations have been done to investigate the effect of oxygen on the gain and efficiency. One method to remove the ageing is HV training. In this procedure the applied voltage is increased such, that the OT enters the discharge regime. These discharges mostly remove the ageing, but can take place anywhere in the straw tube, not necessarily at the location of the a...

  14. Thermosetting polymer for dynamic nuclear polarization: Solidification of an epoxy resin mixture including TEMPO

    Energy Technology Data Exchange (ETDEWEB)

    Noda, Yohei, E-mail: [Quantum Beam Science Centre, Sector of Nuclear Science Research, Japan Atomic Energy Agency, Shirakata-Shirane, Tokai, Ibaraki 319-1195 (Japan); Kumada, Takayuki [Quantum Beam Science Centre, Sector of Nuclear Science Research, Kansai Photon Science Institute, Japan Atomic Energy Agency, Kizugawa, Kyoto 619-0215 (Japan); Yamaguchi, Daisuke; Shamoto, Shin-ichi [Quantum Beam Science Centre, Sector of Nuclear Science Research, Japan Atomic Energy Agency, Shirakata-Shirane, Tokai, Ibaraki 319-1195 (Japan)


    We investigated the dynamic nuclear polarization (DNP) of typical thermosetting polymers (two-component type epoxy resins; Araldite{sup ®} Standard or Araldite{sup ®} Rapid) doped with a (2,2,6,6-tetramethylpiperidine-1-yl)oxy (TEMPO) radical. The doping process was developed by carefully considering the decomposition of TEMPO during the solidification of the epoxy resin. The TEMPO electron spin in each two-component paste decayed slowly, which was favorable for our study. Furthermore, despite the dissolved TEMPO, the mixture of the two-component paste successfully solidified. With the resulting TEMPO-doped epoxy-resin samples, DNP experiments at 1.2 K and 3.35 T indicated a magnitude of a proton-spin polarization up to 39%. This polarization is similar to that (35%) obtained for TEMPO-doped polystyrene (PS), which is often used as a standard sample for DNP. To combine this solidification of TEMPO-including mixture with a resin-casting technique enables a creation of polymeric target materials with a precise and complex structure.

  15. Shear and Thermal Testing of Adhesives for VELO Upgrade

    CERN Document Server

    De Capua, Stefano; Klaver, Suzanne; Parkes, Chris; Rodriguez Perez, Pablo; Shtipliyski, Antoni; Stelmasiak, Guy James


    As part of the R&D process of the LHCb VELO Upgrade, a study has been performed on the thermal and mechanical performance of the adhesives Stycast 2850FT, 3M 9461P, and Araldite 2011. One or more of these adhesives could be used to attach the ASICs and hybrids to the microchannel cooling substrate. Samples were irradiated at up to the maximum dose expected at the upgrade. Shear tests of the samples were made and a suitable performance obtained from all glues. Some failures were encountered with Stycast 2850FT glued samples and this is attributed to the sample preparation. The relative thermal conductivities of the adhesives were also determined by measuring the relative temperature difference across a glued joint while one side is heated.

  16. Modelling and Numerical Simulations of In-Air Reverberation Images for Fault Detection in Medical Ultrasonic Transducers: A Feasibility Study

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    W. Kochański


    Full Text Available A simplified two-dimensional finite element model which simulates the in-air reverberation image produced by medical ultrasonic transducers has been developed. The model simulates a linear array consisting of 128 PZT-5A crystals, a tungsten-epoxy backing layer, an Araldite matching layer, and a Perspex lens layer. The thickness of the crystal layer is chosen to simulate pulses centered at 4 MHz. The model is used to investigate whether changes in the electromechanical properties of the individual transducer layers (backing layer, crystal layer, matching layer, and lens layer have an effect on the simulated in-air reverberation image generated. Changes in the electromechanical properties are designed to simulate typical medical transducer faults such as crystal drop-out, lens delamination, and deterioration in piezoelectric efficiency. The simulations demonstrate that fault-related changes in transducer behaviour can be observed in the simulated in-air reverberation image pattern. This exploratory approach may help to provide insight into deterioration in transducer performance and help with early detection of faults.

  17. Bolted Joints in Three Axially Braided Carbon Fibre/Epoxy Textile Composites with Moulded-in and Drilled Fastener Holes (United States)

    Ataş, Akın; Gautam, Mayank; Soutis, Constantinos; Potluri, Prasad


    Experimental behaviour of bolted joints in triaxial braided (0°/±45°) carbon fibre/epoxy composite laminates with drilled and moulded-in fastener holes has been investigated in this paper. Braided laminates were manufactured by vacuum infusion process using 12 K T700S carbon fibres (for bias and axial tows) and Araldite LY-564 epoxy resin. Moulded-in fastener holes were formed using guide pins which were inserted in the braided structure prior to the vacuum infusion process. The damage mechanism of the specimens was investigated using ultrasonic C-Scan technique. The specimens were dimensioned to obtain a bearing mode of failure. The bearing strength of the specimens with moulded-in hole was reduced in comparison to the specimens with drilled hole, due to the increased fibre misalignment angle following the pin insertion procedure. An improvement on the bearing strength of moulded-in hole specimens might be developed if the specimen dimensions would be prepared for a net-tension mode of failure where the fibre misalignment would not have an effect as significant as in the case of bearing failure mode, but this mode should be avoided since it leads to sudden catastrophic failures.

  18. Chemical Analysis of Emu Feather Fiber Reinforced Epoxy Composites

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    V.Chandra sekhar


    Full Text Available A composite is usually made up of at least two materials out of which one is binding material called as matrix and other is a reinforcement material known as fiber. For the past ten years research is going on to explore possible composites with natural fiber like plant fibers and animal fibers. The important characteristics of composites are their strength, hardness light in weight. It is also necessary to study about the resistance of the composites for deferent chemicals. In the present work, composites prepared with epoxy (Araldite LY-556 as resin and „emu‟ bird feathers as fiber have been tested for chemical resistance. The composites were prepared by varying fiber loading (P of „emu‟ feathers ranging from 1 to 5 and length (L of feather fibers from 1 to 5 cm. The composites thus prepared were subjected to various chemicals (Acids, Alkalis, solvents etc.. Observations were plotted and studied. The results reveal that there will be weight gain for the composite samples after three days, when treated with Hydrochloric acid, Sodium carbonate, Acetic acid, Sodium hydroxide, Nitric acid and Ammonium hydroxide. Weight loss was observed for all the samples including pure epoxy when treated with Benzene, Carbon tetra chloride and Toluene.

  19. Ultrastructural changes in blood vessels in epidermal growth factor treated experimental cutaneous wound model. (United States)

    Kılıçaslan, Seda M Sarı; Cevher, Sule Coşkun; Peker, Emine G Güleç


    This study investigates the impact of epidermal growth factor (EGF) on blood vessels, specifically on the development of intussusceptive angiogenesis in cutaneous wound healing. Excisional wounds were formed on both sides of the medulla spinalis in dorsal location of the rats. The control and EGF-treated groups were divided into two groups with respect to sacrifice day: 5 d and 7 d. EGF was topically applied to the EGF-treated group once a day. The wound tissue was removed from rats, embedded in araldite and paraffin, and then examined under transmission electron and light microscopes. The ultrastructural signs of intussusceptive angiogenesis, such as intraluminal protrusion of endothelial cells and formation of the contact zone of opposite endothelial cells, were observed in the wound. Our statistical analyses, based on light microscopy observations, also confirm that EGF treatment induces intussusceptive angiogenesis. Moreover, we found that induction of EGF impact on intussusceptive angiogenesis is higher on the 7th day of treatment than on the 5th day. This implies that the duration of EGF treatment is important. This research clarifies the effects of EGF on the vessels and proves that EGF induces intussusceptive angiogenesis, being a newer model with respect to sprouting type.

  20. Morphology of Donor and Recipient Nerves Utilised in Nerve Transfers to Restore Upper Limb Function in Cervical Spinal Cord Injury

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    Aurora Messina


    Full Text Available Loss of hand function after cervical spinal cord injury (SCI impacts heavily on independence. Multiple nerve transfer surgery has been applied successfully after cervical SCI to restore critical arm and hand functions, and the outcome depends on nerve integrity. Nerve integrity is assessed indirectly using muscle strength testing and intramuscular electromyography, but these measures cannot show the manifestation that SCI has on the peripheral nerves. We directly assessed the morphology of nerves biopsied at the time of surgery, from three patients within 18 months post injury. Our objective was to document their morphologic features. Donor nerves included teres minor, posterior axillary, brachialis, extensor carpi radialis brevis and supinator. Recipient nerves included triceps, posterior interosseus (PIN and anterior interosseus nerves (AIN. They were fixed in glutaraldehyde, processed and embedded in Araldite Epon for light microscopy. Eighty percent of nerves showed abnormalities. Most common were myelin thickening and folding, demyelination, inflammation and a reduction of large myelinated axon density. Others were a thickened perineurium, oedematous endoneurium and Renaut bodies. Significantly, very thinly myelinated axons and groups of unmyelinated axons were observed indicating regenerative efforts. Abnormalities exist in both donor and recipient nerves and they differ in appearance and aetiology. The abnormalities observed may be preventable or reversible.

  1. Rapid embedding methods into epoxy and LR White resins for morphological and immunological analysis of cryofixed biological specimens. (United States)

    McDonald, Kent L


    A variety of specimens including bacteria, ciliates, choanoflagellates (Salpingoeca rosetta), zebrafish (Danio rerio) embryos, nematode worms (Caenorhabditis elegans), and leaves of white clover (Trifolium repens) plants were high pressure frozen, freeze-substituted, infiltrated with either Epon, Epon-Araldite, or LR White resins, and polymerized. Total processing time from freezing to blocks ready to section was about 6 h. For epoxy embedding the specimens were freeze-substituted in 1% osmium tetroxide plus 0.1% uranyl acetate in acetone. For embedding in LR White the freeze-substitution medium was 0.2% uranyl acetate in acetone. Rapid infiltration was achieved by centrifugation through increasing concentrations of resin followed by polymerization at 100°C for 1.5-2 h. The preservation of ultrastructure was comparable to standard freeze substitution and resin embedding methods that take days to complete. On-section immunolabeling results for actin and tubulin molecules were positive with very low background labeling. The LR White methods offer a safer, quicker, and less-expensive alternative to Lowicryl embedding of specimens processed for on-section immunolabeling without traditional aldehyde fixatives.


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    Full Text Available The aim of this investigation is to comprehensively understand the polymeric composite behavior under direct fire sources. The synergistic effects of hybrid flame retardant material on inhabiting the pyrolysis of hybrid reinforced fibers, woven roving (0°- 45° carbon and kevlar (50/50 wt/wt, and an araldite resin composites were studied. The composites were synthesised and coated primarily by zinc borate (2ZnO.3B2O3.3.5H2O and modified by antimony trioxide (Sb2O3 with different amounts (10-30 wt% of flame retardant materials. In the experiments, the composite samples were exposed to a direct flame source generated by oxyacetylene flame (~3000ºC at variable exposure distances of 10-20 mm. The synergic flame retardants role of antimony trioxide and zinc borate on the composite surface noticeably improves the flame resistance of the composite which is attributed to forming a protective mass and heat barrier on the composite surface and increasing the melt viscosity.

  3. Ultrastructural and lectin-histochemical differences between the scolex/strobila and bladder teguments of the Taenia taeniaeformis strobilocercus. (United States)

    Olson, E J; Oaks, J A; Osmundson, G D; Hildreth, M B


    The strobilocercus stage of the cat tapeworm Taenia taeniaeformis is surrounded by a single syncytial sheet of cytoplasm called the tegument. The outer membrane of the tegument covers both the scolex/strobila (S/S) and the bladder portions of the strobilocercus, but only the S/S region is resistant to intestinal digestion. It has been suggested that the glycocalyx, the surface-exposed glycoconjugates of the outer membrane, may serve to insulate underlying surface membrane components from digestion. In this study, we used lectin binding to test the hypothesis that the glycocalyx of the S/S is different from that of the bladder and that this may serve as the resistance mechanism of the S/S to digestion. Biotin-labeled lectins and an avidin-glucose oxidase detection system were applied to whole strobilocerci and to 1-microm epon-araldite plastic-embedded sections. Lectins bound to either both regions of the strobilocerci, to the S/S regions only, or did not bind at all. The restriction of some glycoconjugates to the glycocalyx of the S/S region only is consistent with our hypothesis.

  4. Of plants and other pets: practical aspects of freeze-substitution and resin embedding. (United States)

    Hess, M W


    Representative tissues from higher plants (e.g. developing pollen, somatic anther tissues from the monocotyledonous angiosperm Ledebouria) and mammalian cell cultures were successfully cryoimmobilized by means of high-pressure freezing. Various substitution and embedding protocols were then evaluated considering the preservation of ultrastructural details, membrane staining, immunolabelling properties, as well as reproducibility and ease of use. Two types of recipe proved to be highly suitable for most applications, regardless of type, developmental stage or physiological conditions of the cells: (i) the best choice for morphology is still osmium in acetone (optionally supplemented with uranyl acetate) followed by embedding in Epon and/or Araldite; (ii) feasible approaches for immunocytochemistry are freeze-substitution with ethanol containing uranyl acetate and formaldehyde, or with pure acetone (in the case of fixation-sensitive antigens), followed by embedding with LR-white acrylic resin; though being far from optimal, these combinations represent, in my opinion, an acceptable compromise between labelling intensity, section stability, structural preservation and health hazards. Notably, the patterns observed in Ledebouria were consistent with data obtained from a broad range of other specimens from all kingdoms (e.g. leaves and callus cultures from angiosperms, gymnosperm roots with their ectomycorrhizal fungi, mammalian cell cultures and eubacteria). Finally, a warning is given as to the extractive potentials of embedding resins (Spurr's mixture, LR-white, but also Epon) being sometimes the cause of unacceptable artefacts, both in plant and in mammalian cells prepared by cryoimmobilization and freeze-substitution.

  5. Improved immunoelectron microscopic method for localizing cytoskeletal proteins in Lowicryl K4M embedded tissues. (United States)

    Loesser, K E; Doane, K J; Wilson, F J; Roisen, F J; Malamed, S


    We have modified the Lowicryl K4M low-temperature dehydration and embedding procedure for immunoelectron microscopy to provide improved ultrastructural detail and facilitate the localization of actin and tubulin in isolated rat adrenocortical cells, chick spinal cord with attached dorsal root ganglia (SC-DRG), and cultured dorsal root ganglia (DRG). Cells and tissues were fixed for immunocytochemistry either in a mixture of 2% paraformaldehyde and 0.25% glutaraldehyde (0.1 M PIPES buffer, pH 7.3) or in a mixture of 0.3% glutaraldehyde and 1.0% ethyldimethylaminopropylcarbodiimide (0.1 M phosphate buffered saline, pH 7.3). Dehydration was in ethanol at progressively lower temperatures to -35 degrees C. Infiltration at -35 degrees C was followed by ultraviolet polymerization at -20 degrees C. Comparable samples were fixed in glutaraldehyde and osmium tetroxide and embedded in Epon 812 or Epon-Araldite. Post-embedding immunostaining of thin sections utilized commercially available monoclonal antibodies to tubulin and actin followed by the protein A-gold technique (Roth et al., Endocrinology 108:247, 1981). Actin immunoreactivity was observed at the periphery of mitochondria and between mitochondria and lipid droplets in rat adrenocortical cells and at the periphery of neuronal cell processes of SC-DRG. Tubulin immunoreactivity was associated with microtubules throughout neurites of cultured DRG. Our modified technique allows preservation of ultrastructural details as well as localization of antigens by immunoelectron microscopy.

  6. Ultrastructural analysis of glands located in the wall of the congenital fistulae of the lower lip of patients with Van der Woude syndrome Análise ultra-estrutural das glândulas localizadas na parede da fístula congênita de lábio inferior de pacientes com a síndrome de Van der Woude

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    Mirian Aparecida Onofre


    Full Text Available The objective of the present study was to evaluate the glands of wall of congenital fistulae of the lower lip with the transmission electron microscope in order to characterize their microstructural pattern. Thin section of Araldite resin embedded congenital fistulae of the lower lip of four patients with Van der Woude syndrome from the Hospital de Reabilitação de Anomalias Craniofaciais da Universidade de São Paulo, Bauru, SP, were analyzed with a transmission electron microscope. The results showed that the glands were mostly made by typical mucous acini exhibiting, with certain frequency, myoepithelial cells surrounding them. In some of lobules, a few acini smaller than the typical mucous, showed granules of moderate electron density or containing a dense core or exhibiting small dense spherule and predominance granular material. These granules resemble to described recently by others in various human minor salivary glands. We concluded that glands associated with congenital fistula of lower lip of patients with Van der Woude syndrome, in spite of being located in vermilion border of the lip, showed at the transmission electron microscope characteristics of labial minor salivary gland, i.e, are mostly mucous with a few seromucous units, while typical seromucous demilunes are not present.O objetivo do presente estudo foi avaliar a ultraestrutura de glândulas da parede de fístula congênita de lábio inferior ao microscópio eletrônico de transmissão para caracterizar seu padrão microestrutural. Deste modo, as fístulas congênitas de 4 pacientes com a síndrome de Van der Woude do Hospital de Reabilitação de Anomalias Craniofaciais da Universidade de Sâo Paulo, Bauru, SP, foram processadas para inclusão em resina Araldite e os cortes finos foram analisados no microscópio eletrônico de transmissão. Os resultados mostraram que as glândulas estavam constituídas por ácinos mucosos típicos exibindo com certa freqüência c

  7. Biomechanical Stability of Juvidur and Bone Models on Osteosyntesic Materials (United States)

    Grubor, Predrag; Mitković, Milorad; Grubor, Milan; Mitković, Milan; Meccariello, Luigi; Falzarano, Gabriele


    Introduction: Artificial models can be useful at approximate and qualitative research, which should give the preliminary results. Artificial models are usually made of photo-elastic plastic e.g.. juvidur, araldite in the three-dimensional contour shape of the bone. Anatomical preparations consist of the same heterogeneous, structural materials with extremely anisotropic and unequal highly elastic characteristics, which are embedded in a complex organic structure. The aim of the study: Examine the budget voltage and deformation of: dynamic compression plate (DCP), locking compression plate (LCP), Mitkovic internal fixator (MIF), Locked intramedullary nailing (LIN) on the compressive and bending forces on juvidur and veal bone models and compared the results of these two methods (juvidur, veal bone). Material and Methods: For the experimental study were used geometrically identical, anatomically shaped models of Juvidur and veal bones diameter of 30 mm and a length of 100 mm. Static tests were performed with SHIMADZU AGS-X testing machine, where the force of pressure (compression) increased from 0 N to 500 N, and then conducted relief. Bending forces grew from 0 N to 250 N, after which came into sharp relief. Results: On models of juvidur and veal bones studies have confirmed that uniform stability at the site of the fracture MIF with a coefficient ranking KMIF=0,1971, KLIN=0,2704, KDCP=0,2727 i KLCP=0,5821. Conclusion: On models of juvidur and veal bones working with Shimadzu AGS-X testing machine is best demonstrated MIF with a coefficient of 0.1971. PMID:27708489

  8. Elastic Plastic Stress Distributions in Weld-bonded Lap Joint under Axial Loading

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    Essam A. Al-Bahkali


    Full Text Available Weld-bonding process is increasingly used in many industries such like automobile and aerospace. It offers significant improvements of sheet metal joints in static, dynamic, corrosion, noise resistance, stiffness and impact toughness properties. A full understanding of this process, including the elastic-plastic stress distribution in the joint, is a must for joints design and automation of manufacturing. Also, the modelling and analysis of this process, though it is complex, proves to be of prime importance. Thus, in this study a systematic experimental and theoretical study employing Finite Element Analysis (FEA is conducted on the weld-bonded joint, fabricated from Austenitic Stainless steel (AISI 304 sheets of 1.00 mm thickness and Epoxy adhesive Araldite 2011, subjected to axial loading. Complete 3-D finite element models are developed to evaluate the normal, shear and triaxial Von Mises stresses distributions across the entire joint, in both the elastic and plastic regions. The, needed quantities and properties, for the FE modelling and analysis, of the base metals and the adhesive, such like the elastic-plastic properties, modulus of elasticity, fracture limit, the nugget and Heat Affected Zones (HAZ properties, etc., are obtained from the experiments. The stress distribution curves obtained are found to be consistent with those obtained from the FE models and in excellent agreement with the experimental and theoretical published data, particularly in the elastic region. Furthermore, the stress distribution curves obtained for the weld-bonded joint display the best uniform smooth distribution curves compared to those obtained for the spot and bonded joint cases. The stress concentration peaks at the edges of the weld-bonded region, are almost eliminated resulting in achieving the strongest joint.

  9. Polymer Magnetic Composite Core Based Microcoils and Microtransformers for Very High Frequency Power Applications

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    Saravana Guru Mariappan


    Full Text Available We present a rapid prototyping and a cost effective fabrication process on batch fabricated wafer-level micro inductive components with polymer magnetic composite (PMC cores. The new PMC cores provide a possibility to bridge the gap between the non-magnetic and magnetic core inductive devices in terms of both the operating frequency and electrical performance. An optimized fabrication process of molding, casting, and demolding which uses teflon for the molding tool is presented. High permeability NiFeZn powder was mixed with Araldite epoxy to form high resistive PMC cores. Cylindrical PMC cores having a footprint of 0.79 mm 2 were fabricated with varying percentage of the magnetic powder on FR4 substrates. The core influence on the electrical performance of the inductive elements is discussed. Inductor chips having a solenoidal coil as well as transformer chips with primary and secondary coils wound around each other have been fabricated and evaluated. A core with 65% powder equipped with a solenoid made out of 25 µm thick insulated Au wire having 30 turns, yielded a constant inductance value of 2 µH up to the frequency of 50 MHz and a peak quality factor of 13. A 1:1 transformer with similar PMC core and solenoidal coils having 10 turns yielded a maximum efficiency of 84% and a coupling factor of 96%. In order to protect the solenoids and to increase the mechanical robustness and handling of the chips, a novel process was developed to encapsulate the components with an epoxy based magnetic composite. The effect on the electrical performance through the magnetic composite encapsulation is reported as well.

  10. Morphometry study on pre and post-hatching nerve cell bodies of lumbar spinal ganglia of Gallus domesticus

    Directory of Open Access Journals (Sweden)

    Claudio A. Ferraz de Carvalho


    Full Text Available A cytomorphometric study was performed in lumbar spinal ganglia neurons of Gallus domesticus on the 10th and 18th incubation days and 8th, 35th, 61st, and 120th post-hatching days. The absolute volume of nucleus and relative volume of cytoplasm were respectively estimated by the Bach² caryometric method and by point-counting volumetry, carried out in 0.5mm thick araldite sections. The relative volume, the surface-to-volume ratio and the total surface of RER, SER, mitochondria, dense bodies, Golgi complex and the relative volume of hyaloplasm inside and outside the Nissl bodies were estimated from electronmicrographs by the Weibel et al.58 method. The conclusions were: a there was an increase of the cell volume and a decrease of the nucleo-cytoplasmic ratio, particularly between the first two ages; b the relative volumes of RER and SER change inversely with respect to each other: the RER increases before hatching, decreasing progressively afterwards; the changes of relative volume of dense bodies are similar to those of the RER, and the mitochondria show relatively small variations concerning the same parameter; c the relative volume of hyaloplasm inside the Nissl bodies decreases while those outside increases; d the surface-to-volume ratio drops sharply for all organelles from the 10th to the 18th day of incubation; after hatching, a tendency to increase is observed; e the membrane surface-to-cytoplasmic volume ratio decreases for all organelles from the 10th to the 18th day of incubation; after hatching, this ratio increases slightly for mitochondria and Golgi complex, sharply for SER, dropping for dense bodies. The RER values alternate regularly.

  11. Dorsal raphe nucleus of brain in the rats flown in space inflight and postflight alteration of structure (United States)

    Krasnov, I.

    The structure of brain dorsal raphe nucleus (DRN) was studied in the rats flown in space aboard Space Shuttle "Columbia" (STS-58, SLS-2 program) and dissected on day 13 of the mission ("inflight" rats) and in 5-6 hours after finishing 14-day flight ("postflight" rats). The brain of "inflight" rats were excised after decapitation, sectioned sagitally halves of brain were fixed by immersion in 2,5 % glutaraldehyde in 0.1 M cacodylate buffer pH 7.3 at 4°C and kept in the flight at 4°C. After landing the brain frontal 0.5 mm sections from DRN area were osmificated and embedded in araldite at NASA ARC. The brains of "postflight": and control rats were underwent to the same procedure. Electronmicroscopical analysis, computer morphometry and glial cell count were performed at Moscow. In DRN neuropil of "inflight" rats the most part of axo-dendritic synapses were surrounded by glia cell processes and had decreased electron density of pre- and postsynaptic membrane and pronounced diminution of synaptic vesicle amount while dendrites were characterized by decrease in matrix electron density and microtubule quantity that in total indicates the decline of afferent flow reaching DRN neurons in microgravity. In DRN neurons of "inflight" rats all mitochondria were characterized by evenly increased dimensions, decreased matrix electron density, small amount of short and far- between located cristae and enlarged intermembrane and intercristae spaces, that in total points out low level of coupling of oxidation to phosphorilation, decrease in energy supply of neuron. Amount of ribosome in cytoplasm was significantly decreased indicating lower lever of biosynthetic processes. The last is supported by diminished dimensions of neuronal body, nucleus and nucleolus (place of r RNA synthesis), cross section area of that were reduced in DRN neurons of "inflight" rats by 18.8 % (p < 0.01), 11.1 % and 26.6 % (p <0,005) correspondingly. Ultrastructure and dimensions of intracellular

  12. Conception, fabrication et caracterisation d'un panneau adaptatif en composite avec actionneurs en amf integres (United States)

    Lacasse, Simon

    This research project has developed a tool to predict the geometry of an adaptive panel which has the ability to change its geometry according to the surrounding conditions under which it is subjected. This panel, as designed for this project, consists of two main components: the host structure that ensures the structural integrity of the panel and the activation system embedded in the host structure. The host structure is made of a fiber-reinforced (carbon: Toray T300 unidirectional) polymer (Epoxy: Huntsman Araldite 8605). The actuation system consists of shape memory alloy wire (SAES Getters Ti-50.26at%Ni) of one mm diameter. To generate the movement, the actuators are positioned to create an offset, along the thickness, between the neutral plane of the laminate and the axis of the actuators. Shape memory alloys are special materials that have the ability to contract themselves when heated. When heated by Joule effect, the actuators contract and generate forces which are transmitted to the adaptive panel through a fixation device. A bending moment is thus generated by the difference between the actuator and the neutral plane of the panel, deforming the adaptive panel. The design tool is based on the combination of the rigidity of the host structure and the operating capacity of the SMA. A finite element model is developed on the commercial software ANSYS 13. This model provides the stiffness of the host structure depending on various parameters of the laminate (orientation and number of plies) and of the actuator (position along the thickness, distance between two actuators). According to this model, it appears that the radius of curvature of such a panel is constant throughout its length and that the panel's length does not influence the results. In addition, the results show that the stiffness is constant regardless of the axial deformation of the actuator. Interestingly, the greater the distance between the actuators, the greater is the stiffness felt by each

  13. Degradation processes and consolidation of Late Jurassic sandstone dinosaur tracks in museum environment (Museum of Lourinhã, Portugal) (United States)

    Leal, Sofia; mateus, Octavio; Tomas, Carla; Dionisio, Amelia


    The current study aims to conciliate conservation and restoration museology diagnosis with paleontological and geological curational needs and has, as subject of study, dinosaur footprints (vertebrates fossils). The footprints have been being exposed since 2004 in the paleontology hall of the Museum of Lourinhã, Portugal, and are part of a important paleontological collection of Late Jurassic vertebrate fossils from Lourinhã Formation. Presently, it is considered a unique heritage in danger of disappearing due to high decay level of disaggregation of its geological structure. The dinosaur footprints, (ML557) found, more precisely, on a coastline cliff in Lourinhã, Porto das Barcas, Lagido do Forno (coordinate 39° 14. 178'N, 9° 20. 397'W), Jurassic period, on the 5th of June 2001, by Jesper Milàn. This cliff of high slope presents sedimentary stratigraphic characteristics of a sandstone/siltstone of gray and red colors, by the '' Munsell scale and Color Chart''. Geological the tracks are Late Jurassic in age, and colected in the Lourinhã Formation, Praia Azul Member, of the Lusitanian Basin. There are three natural infills tridactyl tracks, possibly ascribed to ornithopod, a bipedal herbivore, resultant of a left foot movement, right and left. Footprints have 300-400mm of wide and 330-360mm of height with round fingers, which are elongated due to some degradation/erosion. In 2001, the footprints were collected from the field, cleaned, consolidated and glued in the laboratory of the Museum of Lourinhã before being exhibited in a museum display. Stone matrix was removed and a consolidation product applied, probably a polyvinyl acetate, of the brand Plexigum. The footprint with broken central digit was glued with an epoxy resin, Araldite. Both applied products were confirmed by analysis of µ-FTIR (Fourier Transform Infrared Spectroscopy) and both presented colour change and detachment surface problems. After collecting and storing, in 2004, footprints were

  14. Processing-property relationships in epoxy resin/titanium dioxide nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Polyzos, Georgios [ORNL; Tuncer, Enis [ORNL; Sauers, Isidor [ORNL; More, Karren Leslie [ORNL


    In situ precipitated titanium dioxide nanoparticles improve the physical properties of polymer composites. Since the pioneering work at Toyota Research Center on exfoliated montmorillonite nanoparticles in a nylon matrix, extensive studies have been performed on polymer nanocomposites in an effort to better integrate organic and inorganic phases. Inorganic fillers, such as silicon and titanium oxides, are widely used because of their remarkable enhancement of the mechanical, electrical, barrier, and flame-retardancy properties of organic polymers. The dispersion and size of the fillers determine the performance of nanocomposites and, despite numerous methods and processing conditions reported in the literature, a universally simple method to scale up the distribution of nanofillers remains a challenge. A significant part of our research involves formulation of novel nanodielectrics that can withstand high electric fields and exhibit superior mechanical performance. Focusing on nanocomposites operating at cryogenic temperatures, our group developed an in situ method for nucleating titanium dioxide (TiO{sub 2}) nanoparticles in polyvinyl alcohol. We also applied this method to a variety of polymer matrices. Here, we present our recent work on a cryogenic resin filled with TiO{sub 2} nanoparticles. Using a particle-precursor solution from which TiO{sub 2} precipitates, we nucleated nanoparticles within the cryogenic epoxy resin Araldite 5808 (Huntsman Advanced Materials Inc., USA). We fabricated nanocomposite films at low weight percentages ({approx}2.5%) to avoid formation of large aggregates and interfaces. The morphology and dispersion of the in situ synthesized nanoparticles are shown by low- and high-magnification transmission-electron-microscopy (TEM) images. The TiO{sub 2} particles ({le}5nm in diameter) are uniformly nucleated and form evenly distributed nanometer-sized clusters in the polymer matrix. This morphology differs significantly from nanocomposites