Academic literature on the topic 'Bark resin'
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Journal articles on the topic "Bark resin"
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Kain, Günther, Eugenia Mariana Tudor, and Marius-Catalin Barbu. "Bark Thermal Insulation Panels: An Explorative Study on the Effects of Bark Species." Polymers 12, no. 9 (September 19, 2020): 2140. http://dx.doi.org/10.3390/polym12092140.
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Tree bark is a byproduct of the timber industry which accrues in large amounts, because approximately 10% of the volume a log is bark. Bark is used primarily for low-value applications such as fuel or as a soil covering material in agriculture. Within the present study, thermal insulation panels made from larch, pine, spruce, fir and oak tree bark with different resins (urea formaldehyde, melamine formaldehyde, Quebracho, Mimosa) as a binder are discussed. Also, the properties of panels made from larch bark mixed with industrial popcorn are investigated. The physical-mechanical properties of the panels, which are dependent on panel density, bark species, resin type, resin content and particle size, are analyzed. The bark species has a minor effect on the mechanical characteristics of the panels, while the compression ratio is important for the panel strength, and hence, barks with lower bulk density are preferable. Under laboratory conditions, panels made with green tannin resins proved to have adequate properties for practical use. The addition of popcorn is a means to lower the panel density, but the water absorption of such panels is comparably high. The bark type has a minor effect on the thermal conductivity of the panels; rather, this parameter is predominantly affected by the panel density.
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Wang, Changshui, and Tingzhi Liu. "Activated carbon materials derived from liquefied bark-phenol formaldehyde resins for high performance supercapacitors." RSC Advances 6, no. 107 (2016): 105540–49. http://dx.doi.org/10.1039/c6ra20373f.
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Bark phenolic compounds have been used to partially substitute petroleum-based phenol in a resin synthesis due to their similarity. Activated carbons derived from the liquefied bark-phenol formaldehyde resins exhibit excellent capacitance.
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Amen-Chen, C., B. Riedl, X. M. Wang, and C. Roy. "Softwood Bark Pyrolysis Oil-PF Resols. Part 3. Use of Propylene Carbonate as Resin Cure Accelerator." Holzforschung 56, no. 3 (April 29, 2002): 281–88. http://dx.doi.org/10.1515/hf.2002.046.
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Summary Phenol-formaldehyde (PF) resols were prepared with different proportions of phenol replaced with softwood bark pyrolysis oils under varying formaldehyde to phenolics molar ratios and sodium hydroxide contents. Propylene carbonate (PC) was added to these adhesives to improve the cure of resins. The cure behavior was characterized by differential scanning calorimetry (DSC). Cure kinetics and amount of cure of the experimental resin were improved by adding PC to the resins. Low amounts of PC were used (less than 1.5% of PC on a resin solid basis) to avoid premature gelling of the adhesives. Results obtained by DSC suggested that PC catalyzed the resin cure reaction and also participated in resin cross-linking reactions. Low percentages of PC, 0.5 and 1% on a resin solid basis, were added to the experimental resins for bonding strandboards. These addition levels did not significantly improve mechanical properties of strandboards. It is concluded that a PC addition level of more than 1% by wt (on a resin solid basis) should be used to modify the mechanical properties of panels bonded with pyrolysis oil-PF resins.
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Mirski, Radosław, Jakub Kawalerczyk, Dorota Dziurka, Joanna Siuda, and Marek Wieruszewski. "The Application of Oak Bark Powder as a Filler for Melamine-Urea-Formaldehyde Adhesive in Plywood Manufacturing." Forests 11, no. 12 (November 25, 2020): 1249. http://dx.doi.org/10.3390/f11121249.
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The woodworking industry generates a great amount of bark which has not yet found a wider industrial application. None of the previously conducted research has considered oak bark application (which is one of the most often processed wood species in Poland) as a filler for wood adhesives. Moreover, no studies have determined the properties of bark containing melamine-urea-formaldehyde resin (MUF), which increasingly replaces pure urea-formaldehyde adhesives. Thus, the aim of the study was to determine the possibility of grinded oak bark application as a filler for MUF adhesive in plywood manufacturing. The chemical composition of oak bark was evaluated. Properties of liquid resins, such as viscosity, gel time, pH, and solid content, were determined. Chemical interaction between the filler and resin was assessed with using Fourier-transform infrared (FTIR) spectroscopy. Plywood panels manufactured using MUF adhesive filled with different bark concentrations (10%, 15%, 20%, 25%) were tested in terms of such properties as formaldehyde release and bonding quality. Studies have shown an improvement in liquid resin properties. The course of FTIR spectra did not explain the chemical interaction between the polymer and the filler. The addition of oak bark at a concentration of 15% made it possible to produce plywood panels characterized by reduced formaldehyde release and improved bonding quality.
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Alfaro, René I., Fangliang He, Elizabeth Tomlin, and G. Kiss. "White spruce resistance to white pine weevil related to bark resin canal density." Canadian Journal of Botany 75, no. 4 (April 1, 1997): 568–73. http://dx.doi.org/10.1139/b97-063.
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Examination of the bark from the uppermost lateral branches of white spruce, Picea glauca (Moench) Voss, indicated that trees resistant to attack by the white pine weevil, Pissodes strobi Peck, had significantly higher number and density of vertical resin canals per unit of bark area (mm2) than susceptible trees. The number and density of resin canals were also positively correlated with tree growth rate, an indicator of tree vigor. The density of the resin canals found near the periphery of the bark (outer resin canals) had higher correlation with resistance and growth than inner resin canals. Measurements of resin canals on the bark of lateral branches correlated well with measurements on the bark of the leader of the same tree, indicating that lateral samples could be used to screen white spruce for resistance to weevils. Key words: Picea glauca, Pissodes strobi, pest management, tree genetics.
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Denham, Sander O., David R. Coyle, A. Christopher Oishi, Bronson P. Bullock, Kari Heliövaara, and Kimberly A. Novick. "Tree resin flow dynamics during an experimentally induced attack by Ips avulsus, I. calligraphus, and I. grandicollis." Canadian Journal of Forest Research 49, no. 1 (January 2019): 53–63. http://dx.doi.org/10.1139/cjfr-2018-0024.
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The success of tree colonization by bark beetles depends on their ability to overcome host tree defenses, including resin exudation and toxic chemicals, which deter bark beetle colonization. Resin defenses during insect outbreaks are challenging to study in situ, as outbreaks are stochastic events that progress quickly and thus preclude the establishment of baseline observations of non-infested controls. We use synthetic aggregation pheromones to demonstrate that confined Ips bark beetle herbivory can be successfully initiated to provide opportunities for studying interactions between bark beetles and their hosts, including the dynamics of constitutive and induced resin exudation. In Pinus taeda L. plantations between 12 and 19 years old in North and South Carolina, U.S., trees were affixed with pheromone lures, monitored for evidence of bark beetle attacks, and resin samples were collected throughout the growing season. Baiting increased beetle herbivory to an extent sufficient to produce an induced resin response. Attacked trees exuded about three times more resin at some time than control trees. This supports previous work that demonstrated that information on constitutive resin dynamics alone provides an incomplete view of a host tree’s resistance to bark beetle attack.
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Sommerlatte, Hilary, and Ben-Erik Van Wyk. "Observations on the Association between Some Buprestid and Cerambycid Beetles and Black Frankincense Resin Inducement." Diversity 14, no. 1 (January 16, 2022): 58. http://dx.doi.org/10.3390/d14010058.
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Samburu resin harvesters in northern Kenya maintain that frankincense resin flow from Boswellia neglecta and Commiphora confusa is induced by insect larval activity. Observations on the insects’ larval behaviour support these claims. During the frankincense harvest, buprestid beetle larvae, identified as a Sphenoptera species, are found under B. neglecta resin, eating the monoterpene-rich inner bark, which apparently stimulates the trees to produce copious amounts of fresh resin. The same behaviour was observed with cerambycid beetle larvae, identified as Neoplocaederus benningseni Kolbe, on C. confusa trees. Remarkably, these insects have developed the capacity to digest the resin-saturated inner bark and overcome the toxic, repellent characteristics of oleo-monoterpenes. The frankincense resin also appears to act as a protective covering during the insects’ larval and pupal stages. Excessive tree damage was not noted from these insect invasions. Even though the tree species are from different genera, the resin produced by both is black, with a very similar aromatic chemical profile. The question thus arises as to whether the larval feeding behaviour of these beetle species has an influence, not only on the physical appearance but also on the chemical composition of the resins.
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Field, J. A., M. J. H. Leyendeckers, R. Sierra Alvarez, G. Lettinga, and L. H. A. Habets. "The Methanogenic Toxicity of Bark Tannins and the Anaerobic Biodegradability of Water Soluble Bark Matter." Water Science and Technology 20, no. 1 (January 1, 1988): 219–40. http://dx.doi.org/10.2166/wst.1988.0026.
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The principal methanogenic toxins of bark soluble matter were identified as the tannins. The tannins, which were measured with a selective tannin adsorbant called polyvinylpyrrolidone, accounted for about half of the aqueous extractable COD of tree bark. The 50% inhibitory concentration of bark tannins averaged approximately 600 mg COD L−1 (350 mg tannin solids L−1). The toxicity caused by the resin fraction of bark was demonstrated not to be very important to the methanogenic toxicity of aqueous extracts. While tree resin compounds were found to be very toxic to methanogenic bacteria, the solubility of the resin fraction was very poor due to the low natural pH during the aqueous extraction. Additionally, those compounds aqueous extracted from tree resin at the natural pH were not as toxic as all the tree resin compounds solubilized by alkali and supplied at similar concentrations. Anaerobic biodegradability results indicated that 30 to 50% of the bark water soluble COD can be acidified to methanogenic substrates during short term digestion. Pine and birch bark water soluble COD acidified up to 70% after long term batch digestion of 7 weeks. The high level of bark aqueous extract UV absorbance elimination by anaerobic digestion and the appearance of intermediates indicated that at least some of the bark phenolic compounds were included in the methanogenic substrate.
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Derkyi, N. S. A. "Effect of Extraction Solvent on Tannin-Formaldehyde Adhesives for Plywood Production." Journal of Energy and Natural Resource Management 1, no. 2 (February 21, 2018): 120–26. http://dx.doi.org/10.26796/jenrm.v1i0.27.
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Pine bark is a good source of natural polyphenolic compounds for wood adhesives. The objective of this study was to obtainthe most suitable solvent for extracting pine tannins in the preparation of tannin-formaldehyde plywood adhesives. Aqueousacetone, aqueous ethanol, aqueous NaOH and water as solvents were used to obtain crude tannins from pine bark. Thetannin content, sugar content and Stiasny number of the extracts were determined. Using the extracts from the solventextractions, synthesis of tannin-formaldehyde resin was carried out. Plywood panels were made using the synthesized resinsand the quality of the resins in plywood application determined. The quality of tannin-formaldehyde resins produced from thetannins were generally in close agreement with the chemical characteristics of the extracts obtained from the various solventextractions. The aqueous NaOH extraction although gave very high tannin yield (16.1%), its associated high sugar content(33.8%) and very low Stiasny number (49) resulted in poor quality resin. Similarly, although aqueous extraction gave a veryhigh Stiasny number (91), its low tannin yield (8.7%) might not be of commercial interest. The extraction process that gave ahigh tannin yield (12.9%) and a very good Stiasny number (81.5) with a corresponding good quality resin (shear strength =1.9 MPa, 22% delamination) was found for 60% aqueous ethanol extraction.
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Yuniar, Annisa Fitri, I. Wayan Arya Krishnawan Firdaus, and Rahmad Arifin. "THE EFFECT OF ULIN (Eusideroxylon zwageri) STEM BARK EXTRACT ON THE GROWTH OF Candida albicans ON ACRYLIC RESIN DENTURE PLATES." Dentino : Jurnal Kedokteran Gigi 6, no. 1 (May 11, 2021): 31. http://dx.doi.org/10.20527/dentino.v6i1.10637.
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ABSTRACTBackground: Candida albicans is the main microorganism that causes denture stomatitis, thus denture soaking in cleansing solution is needed to protect them from Candida albicans contamination. The 0.2% Chlorhexidine gluconate is one of denture cleansers that induce side effects at prolonged use. An alternative ingredient that can be used as a denture cleanser is ulin stem bark extract. Objective: To determine the effect of ulin stem bark extract at 20%, 40%, 60%, 80%, 100% concentration on the growth of Candida albicans on acrylic resin denture plates. Method: True Experimental with post-test only with control group design was employed under 7 treatment groups consisting ulin stem bark extract at 20%, 40%, 60%, 80%, 100% concentration, 0.2% Chlorhexidine gluconate, and aquadest in a total of 28 samples. Acrylic resin samples that had been exposed to Candida albicans weresoaked in respective treatment for 15 minutes. Results: The average of Candida albicans colonies on acrylic resin denture plates after soaking in ulin bark extract at 20%, 40%, 60%, 80%, 100% concentration, 0.2% Chlorhexidine gluconate, and aquadest were 29.5 CFU/ml, 13.0 CFU/ml, 0 CFU/ml, 0 CFU/ml, 0 CFU/ml, 0 CFU/ml, and 155 CFU/ml. Based on Mann Whitney test, there was no significant difference when ulin stem bark extract at 60% concentration was compared to 0.2% Chlorhexidine gluoconate. Conclusion: Ulin stem bark extract at 20%, 40%, 60%, 80%, and 100% concentration have been proven to reduce Candida albicans colonies on acrylic resin denture plates, and the 60% concentration is equivalent to 0.2% Chlorhexidine gluconate.Keywords: Candida albicans,Eusideroxylon zwageri, Heat cured acrylic resin. Ulin stem bark extract.
Dissertations / Theses on the topic "Bark resin"
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Tahir, Paridah Md. "Utilisation of mangrove bark extracts in cold-setting wood adhesives." Thesis, University of Aberdeen, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327020.
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Extraction of mangrove bark with 4.0% aqueous sodium sulfite and 0.4% aqueous sodium carbonate at 100° and 2 hours gives 24-26% yields compared with extraction by water at 70° for 2 hours which gives 21%. The hot water extracts are more acidic (pH 3.6) than is the sulfite extract (pH 5.6); both are reasonably reactive toward formaldehyde (Stiasny number 70.6 using water and 85.4 using aqueous sulfite-carbonate). The 13C NMR spectra of R. mucronata shows this tannin to have phloroglucinolic A-rings with hydroxy groups at C-5 and C-7 and pyrogallolic B-rings with hydroxy groups at C-3', C-4', and C-5'. The interflavanoid linkages are C-4→C-8 and C-4→C-6. The 13C NMR spectra also indicate the presence of a considerable amount of carbohydrate which is shown to be mainly rhamnose, glucose, arabinose, and uronic acids. Sulfitation of R. mucronata bark reduces the total carbohydrate and the rhamnose extracted but increases the amount of arabinose and uronic acids. The bark storage period has significant effects on the pH and the reactivity of the aqueous tannin solution. Barks stored for <4 weeks produce higher extraction yields than those stored for > 6 weeks and contain significantly larger amount of reactive tannin and have shorter gel times. The reactivity of bark extracts towards formaldehyde can be controlled either by limiting the duration of bark storage to 4 weeks or by maintaining the aqueous tannin solution at pH <10.0. The aqueous tannin solution from R. mucronata exhibited properties such as viscosity, solubility and tackiness which were superior to those from the R. apiculata extract while the mixed R. mucronata-R. apiculata aqueous tannin solution had properties in between these. These barks could be used singly or together as a source of tannin without the bond strength of the resulting glued joints being significantly affected. The "honeymoon" bonding technique improved the bond strengths of joints made using sulfited tannin but is suitable only for tannin solutions containing > 4% aqueous sodium hydroxide. The viscosity of sulfited tannin adhesives is influenced by (a) the amount of aqueous sodium hydroxide added to the aqueous tannin solution, and (b) the lapse time, i.e. the period between the addition of sodium hydroxide to the aqueous tannin solution and the addition of phenol-resorcinol-formaldehyde (PRF) resin, hardener, and paraformaldehyde. The present study shows that with the addition of 5% w/w sodium hydroxide and at a curing temperature of 40° the sulfited tannin extracts from the bark of mangrove trees can replace about 50% w/w of the PRF resin in cold-setting wood adhesives with the production of bond strengths comparable to those produced by 100% PRF resin.
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Duret, Xavier. "Liquéfaction d'écorces en vue de leur valorisation pour le développemnt de nouveaux produits de traitement du bois." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0032/document.
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Les travaux de recherche présentés portent sur l'utilisation des produits de la liquéfaction des écorces d'épicéa dans le phénol pour la préservation du bois. Les produits de la liquéfaction permettent la synthèse d'une résine thermodurcissable de type phénolique. Les résines formulées sont imprégnées dans le bois suivi d'un durcissement in situ. Un prétraitement est mis au point dans le but d'enrichir la fraction phénolique des écorces. Ce prétraitement consiste à hydrolyser les polysaccharides principalement la cellulose et les hémicelluloses dans une solution acide. Ce prétraitement permet d'obtenir un taux de lignine dans les écorces de 60 %, et un taux de cellulose de 28 %. Un procédé de liquéfaction dans un système composé de phénol, d'eau et d'éthanol est optimisé dans le but d'obtenir des taux de liquéfaction supérieur à 85 %, et un taux d'écorces liquéfiées par rapport à la masse de phénol supérieur à 50 %. Les produits de la liquéfaction présentent l'avantage de polymériser sans ajout de formaldéhyde. La durabilité conférée au bois par les résines est bonne, surtout pour les résines phénol/formaldéhyde. Les résines sont peu lessivables. L'imprégnation du bois par les résines provoque un gonflement du bois ce qui améliore la stabilité dimensionnelle de ce dernierThis work focuses on the use of liquefaction products of spruce bark in phenol for the wood preservation. The liquefaction products allow the synthesis of phenolic thermosetting resins. The formulated resins were impregnated into the wood followed by in situ polymerization. A pretreatment was developed in order to increase the phenolic compounds in the spruce bark. This step is an acid hydrolysis of polysaccharides. This pretreatment allowed obtaining a Klason lignin content of 60 %, and a cellulose content of 28 %. A liquefaction process was developed in a mixture of solvent composed of phenol, ethanol, and water. The optimized experimental conditions allowed obtaining a liquefaction yield superior to 85 %, with liqui?ed bark/phenol ratio superior to 50 %. The lique?ed products had the advantage to polymerize without formaldehyde. The resins enhanced the wood durability especially for the phenol/formaldehyde resins. The leaching was low. The wood impregnation allowed a wood swelling, thereby the impregnated wood had a better dimensional stability
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Beaugendre, Camille. "Caractérisation des résines de Calophyllum inophyllum L. : approches déréplicatives pour la recherche de composés antimicrobiens." Thesis, Université Paris Cité, 2019. http://www.theses.fr/2019UNIP5067.
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Perthuison, Julien. "Préparation et vieillissement de matières organiques en contexte archéologique : approche analytique et expérimentale." Thesis, Strasbourg, 2020. http://www.theses.fr/2020STRAF006.
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Cette thèse a été consacrée à la problématique de l’altération de substances organiques en contexte archéologique, avec pour objectifs de donner des clés analytiques et expérimentales pour étudier les processus mis en jeu, d’identifier de nouveaux outils moléculaires indicateurs des processus subis par les matériaux organiques archéologiques et d’interpréter l’impact de ces processus sur les signatures moléculaires de ces matériaux. Après la mise au point d’un protocole expérimental de vieillissement en laboratoire reproduisant les processus « naturels » de vieillissement de substances organiques archéologiques, nous avons déterminé que les réactions croisées entre ingrédients (esters d’acides gras, terpènes) conduit à la formation de composés oligo-/polymériques intéressants à étudier à l’aide de réactions de dégradation chimique. L’étude moléculaire de matériaux organiques archéologiques a aussi été abordée. Ainsi, de la résine de diptérocarpacées provenant de deux épaves asiatiques du XIIème siècle et du brai de bouleau utilisé pour réparer des céramiques néolithiques ont été identifiés. De nouveaux biomarqueurs triterpéniques d’altération issus de la dégradation anaérobie en milieu sédimentaire de triterpènes précurseurs (résine), et des biomarqueurs de traitement thermique intense (brai) ont été caractérisésThe present PhD thesis was devoted to the alteration processes affecting organic substances in an archaeological context, and aimed at providing analytical and experimental keys to investigate the nature of the alteration processes, to identify new molecular tools indicators of archaeological alteration processes and to interpret the impact of these processes on the molecular signatures of these organic materials. Following the development of a laboratory ageing experimental protocol able to reproduce “natural” alteration of archaeological organic substances, we could establish that cross reactions between ingredients (esters of fatty acids, terpenoids) result in the formation oligo/polymeric material worth to be investigated by means of chemical degradation reactions. Additionally, investigation of archaeological organic substances was carried out. Thus, dipterocarpaceae resins from two Asian shipwrecks from the XIInd Century and birch bark tar used to fix Neolithic ceramics have been identified. New triterpenoid biomarkers resulting from the sedimentary anaerobic degradation of parent triterpenoids (resins) and markers indicative of intense thermal treatment (tar) have been characterized
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Conceição, Rafael Novaes da 1978. "Avaliação de nova resina contendo nanopartículas para aplicação na isolação elétrica de barras estatóricas = Evaluation of a new resin containing nanoparticles for application in the electrical insulation of stator bars." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266020.
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Orientador: João Sinézio de Carvalho CamposDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: É bem conhecida a necessidade de energia elétrica para o bem estar e desenvolvimento tecnológico da população em nosso planeta. Ao lado dos avanços científicos de novas tecnologias para geração, existem interesses na melhoria do transporte da energia. Dentre estes se encontram materiais para isolação elétrica de barras estatóricas, quer sejam para melhorar a isolação ou mesmo para reduzir custos. Assim, o presente trabalho visa apresentar resultados da aplicação de uma nova resina epóxi bisfenólica (DGEBF) (RN) à base de nanopartículas de sílica e comparar suas propriedades com a resina epóxi bisfenólica (DGEBA) (RE), atualmente utilizada para a isolação de hidrogeradores. Neste sentido, fabricaram-se protótipos de barras estatóricas, destinadas a hidrogeradores, sendo as resinas impregnadas em sistema VPI (Vácuo-Pressão-Impregnação) e avaliaram-se as propriedades físico-químicas pelas técnicas de viscosimetria, TGA, DSC, MEV e EDS. As propriedades elétricas foram avaliadas pelas técnicas de fator de dissipação (tan delta), descargas parciais, envelhecimento acelerado (VET) e tensão de ruptura. Dentre os resultados das propriedades físico-químicas pode-se comprovar um aumento inicial de três vezes o valor de viscosidade para resina RN em comparação com RE. Entretanto, não houve detrimento das características dielétricas em função da viscosidade, o que foi comprovado através dos resultados de tan delta e VET. Obteve-se um valor de Tg de 116°C e 145°C para RN e RE, respectivamente, o que limitaria a aplicação da resina em geradores por estar abaixo da temperatura de operação. Dentre os resultados dos testes elétricos para as resinas observou-se que: (i) o fator de dissipação e de envelhecimento são praticamente os mesmos para ambas as resinas; (ii) o valor de tip-up resultaram em 0,014 % para RE e 0,020 % para a resina RN, sendo que a norma EN 50209 exige que seja inferior a 0,25% e (iii) a estimativa do tempo de vida útil obtida foi de cerca de 40 anos para os dois tipos de resina, o que é aplicável para maioria dos enrolamentos em operação. Neste sentido sugere-se que a resina RN pode ser uma boa alternativa a resina RE, com um desempenho elétrico equivalente, desde que ajustadas suas condições de processamento e temperatura de aplicação
Abstract: It is well know the demand of electrical energy for the wellbeing and technological development of the population in our planet. Among the scientific development of new technologies for generation, are interests to optimize the energy transport. Among them are materials for electrical insulation of stator bars, whether for improving the insulation or even to reduce the costs. Therefore, the present work aim to present the results of the employment of a new bisphenolic epoxy resin (DGEBF) (RN) containing silica nanoparticles and compare its properties with the bisphenolic epoxy resin (DGEBA) (RE) currently used for the insulation of hydrogenerators. In this context, it was manufactured prototype stator bars, designed for hydrogenerators, being the resins impregnated through VPI (Vacuum-Pressure-Impregnation) system and their physicochemical properties evaluated with the technics of viscosimetry, TGA, DSC, MEV and EDS. The electrical properties were evaluated with the tests of dissipation factor (tan delta), partial discharges, voltage endurance test (VET) and breakdown. Among the results of the physicochemical properties it was possible to verify an initial increase of three times the value of viscosity for RN resin compared to RE. However there was no detriment of the dielectric characteristics depending on the viscosity, what was proven with the results of dissipation factor and VET. It was obtained a value of Tg of 116°C and 145°C for RN and RE respectively, what could limit its employment for hydrogenerators as being below the operational temperature. Among the results of electrical tests for the resins it was observed that: (i) the dissipation factor and VET are practically the same for both resins; (ii) the tip-up value resulted in 0,014% for RE and 0,020% for RN, being required lower than 0,25% according to the norm EN 50209 and (iii) the estimating lifecycle was approximately 40 years for both types of resin, what is applicable for most windings under operation. In this context it is suggested that the RN resin can be a good alternative for RE resin with an equivalent performance once the process conditions and employment temperature are adjusted
Mestrado
Ciencia e Tecnologia de Materiais
Mestre em Engenharia Química
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Rocha, Carlos Ot?vio Jord?o Moreira da. "Compara??o da Avalia??o Mec?nica de Compress?o Axial em Seis Modelos de Fixadores Esquel?ticos Externos Confeccionados com Barras Estabilizadoras de polimetacrilato de metila ou de Madeira e Parafusos de A?o Inoxid?vel 304." Universidade Federal Rural do Rio de Janeiro, 2008. https://tede.ufrrj.br/jspui/handle/tede/902.
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2008 - Carlos Otavio Jordao Moreira da Rocha.pdf: 1867760 bytes, checksum: 3392639adc640e871d82c97af23d8da8 (MD5)
Previous issue date: 2008-08-29With the objective of testing the resistance and the biomechanical behavior of external fixators of low cost used in veterinary medicine, were created 6 prototypes la type manufactured from alternative materials, using as orthopedic implants, stainless steel screws 304 porous, and as stabilized bar the methacrylate resin or wood poles (Pinnus ellioti). The models of the fixators tested differ because they have 2, 3 or 4 implants per fractured segment. With the purpose of doing biomechanical evaluations that are closer to the real clinical situation, were selected 2 tubes of polyvinylchloride, commercially known as PVC, with 10 cm length, internal diameter of 1,27 cm and external diameter of 1,95, far 5 cm from each other, representing, this way, the bone bands and the focus of an unstable fracture. This kind of tube is like a long bone because it has an internal space that represents the medullar area and external walls that represent the two osseous cortical. To each external fixator model, were created 5 prototypes, which were submitted to mechanic tests to evaluate the axial compression strength. The device to evaluate the prototypes was the Instron model 4204, with a charge cell of 5 KN (Kilogram-Newton) and the speed of the axial compression was 2 cm/minute, according the rules ASTM D695-92. The values of rigidity, drainage point and maximum security charge were calculated, according to the methodology used by Willer et al., (1991) and by Falc?o (2004). The mechanical evaluation was done in the Instituto de Macromol?culas Elo?sa Mano in the Universidade Federal do Rio de Janeiro. We concluded that the models with the stabilized bar made of resin required a larger load than the models made of wood to suffer a plastic deformation. The model with 3 screws per segment of PVC tube and a resin stabilized bar showed to tolerate a higher weight than the others, before showing a plastic deformation, this way it s indicated to dogs that weight up to 26,5Kg with fractures in the thoracic limbs and for dogs that weight up to 44Kg that have fractures in the pelvic limbs.
Com objetivo de testar a resist?ncia e o comportamento biomec?nico de fixadores externos de baixo custo utilizados em medicina veterin?ria, foram criados 6 modelos de prot?tipos do tipo Ia confeccionados a partir de materiais alternativos, utilizando-se como implantes ortop?dicos parafusos de a?o inoxid?vel 304 porosos e totalmente rosqueados, e como barra estabilizadora a resina de metacrilato ou hastes de madeira (Pinnus ellioti). Os modelos dos fixadores testados ainda se diferenciam por apresentarem 2, 3 ou 4 implantes por segmento fraturado. Com a finalidade de realizar avalia??es biomec?nicas o mais pr?ximo poss?vel da situa??o cl?nica, optou-se pela escolha de 2 tubos de policloreto de vinila, comercialmente conhecido como PVC, apresentando 10 cm de comprimento, 1,27 cm de di?metro interno e 1,95 cm de di?metro externo, afastados 5 cm entre si, representando assim os fragmentos ?sseos e o foco de uma fratura inst?vel. Este tipo de tubo se assemelha a um osso longo por apresentar um espa?o interno que representa a ?rea medular enquanto que as paredes externas representam as duas corticais ?sseas. Para cada modelo de fixador externo foram criados 5 prot?tipos, submetidos a testes mec?nicos para avalia??o da for?a de compress?o axial. O aparelho para avalia??o dos prot?tipos foi o Instron modelo 4204, com c?lula de carga de 5 KN (Quilograma-Newton) e a velocidade da compress?o axial foi de 2 cm/minuto, seguindo as normas ASTM D695-91. Calculamos as cargas de rigidez, ponto de escoamento e carga de seguran?a m?xima. A avalia??o mec?nica foi realizada no Instituto de Macromol?culas Elo?sa Mano na Universidade Federal do Rio de Janeiro. Conclu?mos que os modelos com barra estabilizadora em resina necessitou de uma carga maior do que os modelos de madeira para sofrer deforma??o pl?stica. O modelo com 3 parafusos por segmento de tubo de PVC e barra estabilizadora de resina mostrou suportar maior peso que os demais, antes de apresentar uma deforma??o pl?stica, sendo indicado para c?es com peso corporal de at? 26,5 Kg portadores de fraturas nos membros tor?cicos e para c?es com peso de at? 44 Kg que apresentem fraturas nos membros p?lvicos.
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Mourad, Firas. "The Effect of Temperature on Different Resin Cements Used for Cementing a Milled Titanium Bar." Thesis, The University of Alabama at Birmingham, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10683963.
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Purpose: To investigate the effect of acrylic processing on push-out strength of Ti copings luted to Milled Ti frameworks using differing resin cements.
Materials and Methods: The experimental design consisted of three groups of 30 specimens each. Three different luting cements were utilized (One for each group), Panavia V5 Dual Cure Kuraray, Multilink Dual Cure Hybrid Ivoclar-Vivadent, and RelyX Unicem-2 self-adhesive 3M. The experimental model consists of trans-mucosal Titanium Coping, Abutment analog, Milled Ti hollow cylinder (9.0mm-OD) represents the milled Ti bar. The Abutment copings were luted to milled-Ti cylinders using the 3 dental cements and an alignment jig to assure repeatability used during cementation. Waxing then acrylic processed by two protocols (Fast and Conventional) for two groups (not the control) were completed. Processed specimens were finished, polished, and stored in distilled H2O at 24 °C for 24 hours prior to testing. Push-out strengths were measured (N/mm2), with Instron 5565 mechanical testing system, crosshead speed 1 mm/min. Failure mode was evaluated by high-magnification light microscopy and SEM. Significance determined by ANOVA and Tukey’s post hoc test (p < 0.05).
Results: Two-way ANOVA shows no significant interaction (p = 0.45 > 0.05) between the two variables, processing technique and the cement. Only the cement is significantly different. So, the cement is not affected by the process and vise-versa. One-way ANOVA shows no significant differences in push-out strength within the same cement groups. However, it has found a difference among the groups (P < 0.0001). Tukey’s post hoc test found significant differences among the cements groups (p < 0.05).
Conclusion: Within the limitations of this in-vitro study, no differences in cement push-out strength were found between acrylic processing methods, but differed by cement type.
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Baggio, Airton [UNESP]. "Aproveitamento dos resíduos de compósitos à base de resina poliéster e fibra de vidro." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/90572.
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baggio_a_me_botfca.pdf: 559829 bytes, checksum: e12ab3a17570794b47bb229f375ebfb5 (MD5)Universidade Estadual Paulista (UNESP)
Nesta pesquisa estudou-se o aproveitamento dos resíduos de compósitos a base de resina poliéster insaturado e fibra de vidro provenientes dos processos de transformação: Moldagem por contato manual Hand lay-up, moldagem por projeção simultânea Spray-up e moldagem por injeção de resina Resin Transfer Moulding - RTM. As rebarbas de compósitos, oriundas das empresas transformadoras, são descartadas como lixo em aterros industriais ou clandestinos e levam décadas para se degradarem, poluindo, desta forma, o meio ambiente. A utilização destes resíduos pode conduzir ao desenvolvimento de uma nova tecnologia competitiva e sustentável. Este trabalho propõe a moagem e micronização das rebarbas de compósitos dando origem a um pó fino, contendo resina mais vidro, e substituição da carga mineral (calcita - CaCO3), tradicionalmente utilizada no processo RTM, por este pó, denominado pó de rebarba de compósito a base de resina poliéster e fibra de vidro. Confeccionaram-se placas de ensaios variando o tipo de carga, entre calcita e pó de rebarba, e a porcentagem em peso da carga na mistura com a resina. Em corpos-de-prova retirados das placas foram realizados ensaios de resistência à tração, resistência à flexão, resistência ao impacto e dureza. Complementarmente, foram realizados ensaios de densidade aparente das cargas, viscosidade da mistura, contração linear, exame microscópico e ensaio prático operacional, contribuindo para avaliar a proposta apresentada. Os resultados obtidos mostraram, que em alguns casos, ocorreram variações de propriedades. Em contrapartida expressaram-se fatores limitantes como por exemplo a viscosidade da mistura contendo pó de rebarba. Entretanto, pode-se afirmar que, tanto tecnicamente quanto operacionalmente, é possível a substituição do pó de calcita pelo pó de rebarba de compósito no processo de moldagem por injeção...
In this research the exploitation of the residues of composites was studied the resin polyester not saturated and fiber glass proceeding from the transformation processes: Molding for manual contact Hand lay-up, molding for simultaneous projection Spray-up and molding for resin injection Resin Transfer Moulding - RTM. The barbs of composites, deriving of the transforming companies, they are discarded as garbage in appropriate or clandestine places and take decades to be degraded, contaminating, of this form, the environment. The use it of these residues can lead to the development of a new competitive and sustainable technology. This work considers the milling and particle's formation of the barbs of composites giving origin to a fine dust, contend resin more glass, e substitution of the mineral load (calcite - CaCO3) traditionally used in process RTM for this dust, called dust of composite barb the resin base polyester and fiber glass. Plates of assays had been confectioned varying the type of load, between calcite and dust of barb, e the percentage in weight of the load in the mixture with the resin. In body-of-test removed of the plates assays of tensile strenght had been carried through, resistance to the flexion, resistance to the impact and hardness. Complementarily, assays of apparent density of loads had been carried through, viscosity of the mixture, linear contraction, microscopical examination and operational practical assay, contributing to evaluate the proposal presented. The gotten results had shown, that in some cases, had occurred variations of properties. On the other hand limitantes factors had been expressed as for example the viscosity of the mixture contends barb dust...(Complete abstract click electronic access below)
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Berglund-Schwarz, Rebecca. "Att ta hänsyn till barnet : En studie av ikonotext i Rose Lagercrantz och Ilon Wiklands Den långa, långa resan." Thesis, Uppsala universitet, Litteraturvetenskapliga institutionen, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385811.
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Hur kan en bok med bilder på fallande bomber, stridsvagnar och en döende hund i en flickas armar vara en barnbok? Hur berättar man egentligen om krig, död och sorg för ett barn? Vad om skiljer barn- och ungdomslitteratur från annan litteratur har länge diskuterats och studerats. Ännu har forskare inte funnit någon definition som alla kan komma överens om, förutom det faktum att den är skriven för en tilltänkt målgrupp. Syftet med uppsatsen är att undersöka hur Ilon Wikland och Rose Lagercrantz berättelse Den långa, långa resan och dess sorgliga motiv adapterats genom att studera verkets ikonotext, den helhet som uppstår vid läsningen av en ”text” konstituerad av både text och bild. Hur texten och bilderna tar hänsyn till dess tilltänkta läsare.
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Baggio, Airton 1960. "Aproveitamento dos resíduos de compósitos à base de resina poliéster e fibra de vidro /." Botucatu : [s.n.], 2005. http://hdl.handle.net/11449/90572.
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Orientador: Alcides Lopes LeãoBanca: Adriano Wagner Ballarin
Banca: José Augusto Marcondes Agnelli
Resumo: Nesta pesquisa estudou-se o aproveitamento dos resíduos de compósitos a base de resina poliéster insaturado e fibra de vidro provenientes dos processos de transformação: Moldagem por contato manual "Hand lay-up", moldagem por projeção simultânea "Spray-up" e moldagem por injeção de resina "Resin Transfer Moulding - RTM". As rebarbas de compósitos, oriundas das empresas transformadoras, são descartadas como lixo em aterros industriais ou clandestinos e levam décadas para se degradarem, poluindo, desta forma, o meio ambiente. A utilização destes resíduos pode conduzir ao desenvolvimento de uma nova tecnologia competitiva e sustentável. Este trabalho propõe a moagem e micronização das rebarbas de compósitos dando origem a um pó fino, contendo resina mais vidro, e substituição da carga mineral (calcita - CaCO3), tradicionalmente utilizada no processo RTM, por este pó, denominado pó de rebarba de compósito a base de resina poliéster e fibra de vidro. Confeccionaram-se placas de ensaios variando o tipo de carga, entre calcita e pó de rebarba, e a porcentagem em peso da carga na mistura com a resina. Em corpos-de-prova retirados das placas foram realizados ensaios de resistência à tração, resistência à flexão, resistência ao impacto e dureza. Complementarmente, foram realizados ensaios de densidade aparente das cargas, viscosidade da mistura, contração linear, exame microscópico e ensaio prático operacional, contribuindo para avaliar a proposta apresentada. Os resultados obtidos mostraram, que em alguns casos, ocorreram variações de propriedades. Em contrapartida expressaram-se fatores limitantes como por exemplo a viscosidade da mistura contendo pó de rebarba. Entretanto, pode-se afirmar que, tanto tecnicamente quanto operacionalmente, é possível a substituição do pó de calcita pelo pó de rebarba de compósito no processo de moldagem por injeção...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In this research the exploitation of the residues of composites was studied the resin polyester not saturated and fiber glass proceeding from the transformation processes: Molding for manual contact "Hand lay-up", molding for simultaneous projection "Spray-up" and molding for resin injection "Resin Transfer Moulding - RTM". The barbs of composites, deriving of the transforming companies, they are discarded as garbage in appropriate or clandestine places and take decades to be degraded, contaminating, of this form, the environment. The use it of these residues can lead to the development of a new competitive and sustainable technology. This work considers the milling and particle's formation of the barbs of composites giving origin to a fine dust, contend resin more glass, e substitution of the mineral load (calcite - CaCO3) traditionally used in process RTM for this dust, called dust of composite barb the resin base polyester and fiber glass. Plates of assays had been confectioned varying the type of load, between calcite and dust of barb, e the percentage in weight of the load in the mixture with the resin. In body-of-test removed of the plates assays of tensile strenght had been carried through, resistance to the flexion, resistance to the impact and hardness. Complementarily, assays of apparent density of loads had been carried through, viscosity of the mixture, linear contraction, microscopical examination and operational practical assay, contributing to evaluate the proposal presented. The gotten results had shown, that in some cases, had occurred variations of properties. On the other hand limitantes factors had been expressed as for example the viscosity of the mixture contends barb dust...(Complete abstract click electronic access below)
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Books on the topic "Bark resin"
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Hellstrand, Åke. Resan genom historien: Barn- och ungdomsböcker från förhistorisk tid till vår egen tid. 2nd ed. Lund: Bibliotekstjänst, 1991.
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Adkins, Mary E. Chesterfield Smith, America's Lawyer. University Press of Florida, 2020. http://dx.doi.org/10.5744/florida/9780813066660.001.0001.
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Chesterfield Smith was one of the boldest lawyers of the twentieth century. A child of a poor, broken household but also a child of a politically connected family, Smith grew up aimless. His World War II combat experience changed him. He returned an ambitious and impatient man who had learned from the European theater what systemized hate and prejudice could do. Smith rose fast, building his small firm to a goliath, leading the Florida Bar, and masterminding the creation of a new state constitution. As president of the American Bar Association during Watergate, his was one of the earliest voices calling for Nixon to obey the law or resign. At home, Smith urged his lawyers to improve the practice of law, and the world around them, by “doing good.” Smith’s larger-than-life personality and drive to improve his surroundings irritated some and inspired many.
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Harris, Frances. 1706–1707. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198802440.003.0009.
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The seventh chapter describes the annus mirabilis of the Marlborough-Godolphin partnership. With Italy and Spain the priorities, Marlborough is given discretionary instructions to march to save Turin. Instead he uses these to induce the Dutch to let him give battle in Flanders. His second great victory at Ramillies wins the Spanish Netherlands back from France and Marlborough is offered the governorship. With success in Spain and Italy, complete success seems in sight. But the Habsburgs lose their opportunity in Spain, the Dutch deny Marlborough the governorship, and the Whigs demand cabinet office for Marlborough’s son-in-law Sunderland, whom the queen dislikes. Godolphin says that if Marlborough will not return and support him he must resign. Believing that they need only one more year to achieve their objectives, Marlborough agrees, but also helps to rebalance the parties. The Whigs are discontented again and Harley now has the queen’s ear.
Book chapters on the topic "Bark resin"
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Gomes, V. N., D. C. Costa, J. Belinha, M. Sampaio-Fernandes, P. Rocha-Almeida, S. J. Oliveira, and M. H. Figueiral. "Acetal resin bars for implant-supported overdentures—FEM." In Advances and Current Trends in Biomechanics, 414–17. London: CRC Press, 2021. http://dx.doi.org/10.1201/9781003217152-91.
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Huang, Mingdeng, Hao Hu, Yong Luo, and Liwen Lv. "Research on Torsional Stiffness of Vehicle Resin Back Door by Sub-Regional Multi-Objective Optimization." In Proceedings of China SAE Congress 2020: Selected Papers, 1117–33. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-2090-4_70.
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Wu, Di, Yafang Han, and Xiayu Jin. "Research on Key Technology of Anti-sliding Treatment of Resin Thin Layer of Bascule Bridge Steel Panel." In Lecture Notes in Civil Engineering, 495–507. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-1260-3_45.
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AbstractThere is relatively little research on steel deck pavement of bascule bridge at home and abroad, which usually adopts the same paving materials and structures as ordinary steel deck, but it can’t meet the normal application conditions. In order to improve the anti-sliding performance of steel deck pavement of bascule bridge, this paper provides a set of steel deck pavement technology of bascule bridge through theoretical analysis of mechanics of bascule bridge and research of pavement materials. The engineering application research shows that the anti-sliding performance of the pavement back layer is obviously improved. After 7 months of application, the pavement layer has a good overall structure, and the bonding strength is still stable at 3.57 MPa, with good durability and good social benefits.
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Tsukahara, Tetsuya. "History of the European-Japanese Cerebrovascular Congress." In Acta Neurochirurgica Supplement, 1–6. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-63453-7_1.
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AbstractThe European-Japanese Cerebrovascular Congress originally started as a Swiss-Japanese joint conference on cerebral aneurysm. The Congress was held in Zürich, Switzerland, from 5–7 May 2001 with Prof. Y. Yonekawa of Zürich and Prof. Y. Sakurai of Sendai as the presidents.Three years later, in July of 2004, the second meeting was held at Zürich again with wide-ranging conference topics on cerebral stroke surgery.The third meeting at Zürich in 2006 was the key congress for future development. The conference was expanded to the European-Japanese Joint Conference for Stroke Surgery.As the year of 2006 was the 70th Anniversary of the Department of Neurosurgery, University Hospital Zürich, Prof. Krayenbühl, Prof. Yasargil, and Prof. Yonekawa introduced the impressive history of the Department of Neurosurgery at the conference.At the fourth European-Japanese Joint Conference on Stroke Surgery we moved from Zürich to the Nordic city of Helsinki, with Prof. Juha Hernesniemi as the conference president.The fifth joint conference was held at Düsseldolf am Rein with Prof. Hans-Jakob Steiger as the Conference president.The sixth conference, named “The European-Japanese Stroke Surgery Conference” (EJSSC), was held in Utrecht, The Netherlands. Professor Luca Regli and Prof. Gabriel Rinkel were the conference presidents.The seventh European-Japanese Stroke Surgery Conference (EJSSC) was held in Verona, Italy with the presidents Prof. Alberto Pasqualin and Prof. Giampietro Pinna.The eighth European-Japanese Cerebrovascular Congress (EJCVC) came back to Zürich in the year 2016 with Prof. Luca Regli as the president.The ninth European-Japanese Cerebrovascular Congress (EJCVC) was held in the historical room of Grande Ospedale Metropolitano Niguarda Milan, Italy, with Prof. Marco Cenzato as the president.The tenth European-Japanese Cerebrovascular Congress (EJCVC) will be held in Kyoto. It will be the first meeting of the EJCVC in Japan.Publication of the proceeding books of the conference as supplements of ACTA Neurochirurgica is one of the main reasons that we have been able to continue this conference for almost 20 years. We sincerely thank Prof. Steiger for his continuous and generous cooperation as the series Editor of ACTA Neurochirurgica.
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Reeve, John D., and Peter Turchin. "Evidence for Predator-Prey Cycles in a Bark Beetle." In Population Cycles. Oxford University Press, 2002. http://dx.doi.org/10.1093/oso/9780195140989.003.0009.
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The southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae), is an economically important pest of pine forests in the southern United States (Price et al. 1992). This native bark beetle is able to attack and kill living trees, typically loblolly (Pinus taeda L.) or shortleaf (Pinus echinata Mill.) pine, through a process of mass attack coordinated by pheromones emitted by the beetle (Payne 1980). During the attack process, thousands of beetles bore through the outer bark of the tree and begin constructing galleries in the phloem layer. Trees can respond to beetle attack by exuding resin from a network of ducts, but the large number of simultaneous attacks usually overcomes this defense, literally draining the resin from the tree. Oviposition and brood development then occur in the girdled (and ultimately dead) tree. Once a tree is fully colonized the attack process shifts to adjacent trees, often resulting in a cluster of freshly attacked trees, trees containing developing brood, and dead and vacated trees (Coulson 1980). These infestations can range in size from a single tree to tens of thousands, although the latter only occur in areas where no control methods are applied. Approximately six generations can be completed in a year in the southern United States (Ungerer et al. 1999). Like many other forest insect pests, D. frontalis populations are characterized by a considerable degree of fluctuation. The longest time series available are Texas Forest Service records of infestations in southeast Texas since 1958 (figure 5.la). These data suggest that the fluctuations have at least some periodic component, with major outbreaks occurring at intervals of 7-9 years (1968, 1976, 1985, and 1992). A variety of different analyses, including standard time series analysis and response surface methodology (Turchin 1990, Turchin and Taylor 1992), suggest that D.frontalis dynamics are indeed cyclic and appear governed by some kind of delayed negative feedback acting on population growth (see chapter 1). This effect can be seen by plotting the realized per-capita rate of growth (R-values) over a year against population density in the previous year (figure 5.1b).
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Dôres, Rosana Gonçalves Rodrigues das, Clarice Silva e. Souza, Maira Christina Marques Fonseca, Juliana Cristina Santos Almeida, Ivan Paiva Barbosa, Fernando Luiz Finger, Giuseppe Micalizzi, Sebastiano Pantò, Valeria Signorino, and Daniele Giuffrida. "JATOBÁ FRUIT (HYMENAEA COURBARIL L. VAR. STILBOCARPA (HAYNE) Y.T. LEE LANGENH.) OIL, RESIN, BARK AND FLOUR ANALYSIS." In Tecnologia de Alimentos: Tópicos Físicos, Químicos e Biológicos - Volume 2, 401–13. Editora Científica Digital, 2020. http://dx.doi.org/10.37885/200700694.
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Loynes, Robert. "How Did Takabuti Die?" In Life and Times of Takabuti in Ancient Egypt, 91–95. Liverpool University Press, 2021. http://dx.doi.org/10.3828/liverpool/9781800348585.003.0016.
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How did Takabuti die? Although initial studies revealed no definitive cause of death, recent analysis has provided intriguing new data: the presence of a penetrating injury in the back of the left upper rib cage that had been sealed with a pack of resin mixed with granular material. There is no evidence of wound-healing, so this is the most likely cause of death. New research attempts to identify the weapons/instruments involved and concludes the Takabuti was murdered. Imaging analysis has also provided information about the mummification procedure. At the time of Takabuti’s death, it was customary to remove the brain by means of a metal hook inserted up the nose. However, in this instance, the brain was extracted more unusually via the foramen magnum at the base of the skull, and exceptionally, the neck area was then filled in with a compact mass of resin. Mummies of this period are frequently filled with a mixture of mud, sawdust, aromatic resins and aromatic substances such as cinnamon. The original investigators of Takabuti found that the body was filled with a mixture of powders: in the current project, the main component in abdominal samples obtained from the mummy was sawdust.
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"Biomechanics of rein-back." In Biomechanics and Physical Training of the Horse, 64–72. CRC Press, 2014. http://dx.doi.org/10.1201/b16104-13.
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Mohd Nazri Wan Abdul Rahman, Wan, Nur Sakinah Mohamed Tamat, Nor Yuziah Mohd Yunus, and Jamaludin Kasim. "Size Effect of Core Strands on the Major Physical and Mechanical Properties of Oriented Strand Boards from Fast Growing Tropical Species." In Engineered Wood Products for Construction [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99953.
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Oriented strand board (OSB) is generally used for sheathing in residential walls, floors, and roofs. Because of its low pricing and utilisation of tiny diameter logs from fast-growing trees and thinning logs as raw materials, OSB is anticipated to gain popularity. In chapter, board properties of OSB using smaller strand size of Leucaena leucocephala as core layer had been studied. Small strand size of S3 (length = 75 mm, width = 3.2 to 6.3 mm) was located in the middle layer of the board while bigger strand sizes of S1 (length = 75 mm, width = 12.7 to 19.0 mm) and S2 (length = 75 mm, width = 6.3 to 12.7 mm) were located at the face and back layers. Utilization of smaller strands (S3) in the middle layers may yield boards that have better physical and mechanical properties. Except for MOR in the minor axis, board density and resin content were shown to have a substantial impact on physical and mechanical properties. Except for MOR in the major axis, strand size had little affected on physical and mechanical properties. The effects of board density on mechanical properties were discovered to affect significantly different. With a positive correlation, board density had a significant effect on thickness swelling. Between S1+S3 and S2+S3 strand size, there is no significant effect on bending properties, internal bond strength and thickness swelling. The effect of resin content on bending properties revealed a significant difference of MOR in major axis, as well as MOE values in both major and minor axes. Even when the resin content was as low as 5%, all treatments of OSB passed the general requirement of general purpose OSB.
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Staniek, Andrzej. "Quality Assessment of Installed Rock Bolts." In Mining Technology [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.101125.
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The chapter presents a method for non-destructive identification of discontinuity of a resin layer (grout) surrounding rock bolts. The method uses modal analysis procedures and is based on an impact excitation where a response transducer is positioned at a visible part of a rock bolt. Since the installed rock bolt acts as an oscillator, its modal parameters are changed by different lengths and positions of grouting discontinuity. Thanks to proper extraction of these parameters, with a resonant frequency seen as the most valuable, the intended identification is possible. The measurements and analyses were performed in laboratory conditions and subsequently at experimental and working coal mines where the measurement system was verified. The developed finite element model of the system under test, rock bolt - resin - rock mass, may be used as reference data base for investigated rock bolts. The advantages of the method include plausibility of grouting discontinuity assessment at any time after its installation, a non-destructive character of the method and the fact that it is not necessary to install any additional equipment into a roof section. It enables a localization of a grout discontinuity, whether it is the back part or the front part of a rock bolt.
Conference papers on the topic "Bark resin"
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Mahfuz, Hassan, Wahid Al Mamun, Hisham Mohamed, Uday Vaidya, Anwarul Haque, and Shaik Jeelani. "High Strain Rate Response of Resin Infusion Molded Sandwich Composites." In ASME 1999 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/imece1999-0909.
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Abstract Foam core sandwich composites have been tested under high strain rate (HSR) loading in the thickness direction. The regular Split Hopkinson Pressure Bar (SHPB) has been modified by replacing the steel transmitter bar by a polycarbonate bar. This modification resulted in stronger signals from the transmitter bar, which would otherwise be very feeble especially when testing soft materials. New sets of mathematical formulations have been derived to account for the impedance mismatch between the incidence and transmitter bars. The modified equations are first verified with a known material and then used for sandwich composites. Three types of core with various densities have been tested under compression at strain rates ranging from quasi-static to 1000 S−1. The compressive failure stress has been observed to be directly proportional to the core density, as well as to the strain rate. The strain rate sensitivity was moderate, and the sandwich composites mostly failed by the collapse of the foam-cell. Delamination did not play a major role in the failure process. Details of the mathematical derivations and the analysis of the HSR behavior are presented in this paper.
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Fukuhara, Tetsuro, Shinichi Suefuji, Kenichi Yasunaga, and Hajime Hasegawa. "Development of resin back door glass for ES3." In International Body Engineering Conference & Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2003. http://dx.doi.org/10.4271/2003-01-2816.
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Hosur, M. V., U. K. Vaidya, N. Jadhav, and S. Jeelani. "Static and High Strain Rate Compression Testing of Thick Section S-2 Glass/Vinyl Ester Composites for Integral Armor Application." In ASME 1998 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/imece1998-1210.
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Abstract Integral armor concepts are of primary interest to armored vehicles requiring ballistic protection. A composite integral armor provides multi-interface, multi-functional capability, easy reparability, quick deployment, enhanced ballistic performance and lightweight advantages. The typical design of integral armor is seen to utilize a combination of thick section S2-glass vinyl ester structural composite, alumina, ceramic tiles, resilient rubber, fire retardant, phenolic layer and several signature/functional layers. Thick composite laminate serves as the primary load-bearing component of the integral armor used in the upper hull of a Composite Armored Vehicle (CAV). Current solution of the structural laminate (typically 0.8” thick) comprises an S2-glass/epoxy automated fiber placed laminate. Currently used processing techniques such as automated fiber placement prove to be costly and time consuming. In the current study, several alternative cost-effective processing solutions are employed. They include Vacuum Assisted Resin Transfer Molding (VARTM) and Vacuum Assisted Resin Infusion Molding (VARI) and their variations. Both VARTM and VARI use low viscosity resins, however, the consolidation conditions that the laminate undergoes are significantly different Composite laminates are made using 45 layer of 2 × 2 twill weave S2-glass with 933 sizing /vinyl ester C-50 resin. Effectiveness of the different fabrication methods is compared in terms of the compression behavior of the laminates. Both static as well as high strain rate test using Split Hopkinson’s bar technique are studied.
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Player, John, Ernesto Villaescusa, and Alan Thompson. "Dynamic testing of fully encapsulated threaded bar – resin and cement grouted." In Seventh International Symposium on Ground Support in Mining and Underground Construction. Australian Centre for Geomechanics, Perth, 2013. http://dx.doi.org/10.36487/acg_rep/1304_16_player.
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Kehua Li, Qiang Guo, Yanjun Zhao, and Dongli Shi. "The study of the resin-bond diamond wheel for IC silicon wafer nanoscale roughness back grinding." In 2011 International Conference on Information Science and Technology (ICIST). IEEE, 2011. http://dx.doi.org/10.1109/icist.2011.5765172.
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Shamsan, Abdulmalek, Alejandro De la Cruz, and Walmy Jimenez. "Successful Barrier Enhancement Application of Epoxy Based Resin for Multiple Casing to Casing Annuli Having Tight Injectivity - Case Study from Saudi Arabian Peninsula." In SPE Middle East Oil & Gas Show and Conference. SPE, 2021. http://dx.doi.org/10.2118/204780-ms.
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Abstract This study describes the approach used for enhancing the well integrity that was compromised with gas flow through a casing-casing annulus (CCA). Extremely tight injectivity at a CCA demands a solid free solution which not only can be injected but also resist high differential pressures to provide a long-term barrier in CCA. In this paper a successful leak remediation using an epoxy resin system helped the operator save a well and restart its production. Several pressure tests were conducted for identifying an extremely tight casing leak which was causing formation gas travelling to surface through the annulus. This issue required the customer to look for an efficient remedial solution to seal off the gas leakage and regain productivity. Due to the extremely low injectivity, a conventional cement squeeze or any solid laden particle-based squeeze approach was prone to fail. Alternatively, a tailored solid free epoxy resin system was placed in the annulus using an unconventional placement technique resulted in barrier enhancement and helped the operator place the well back into production. For a mature well flowing through 7 × 9 5/8‑in. and 9 5/8 × 13 3/8‑in., a tailored epoxy-based resin system formulation was placed in the well bore with modified surface operations procedures which helped in eliminating current annular pressure to regain well integrity and production. Remedial operations were performed from the surface by squeezing to seal off the gas coming from the annulus. A Tailored design derived from rigorous lab testing and perfect field execution resulted in CCA pressure remediation in a single attempt of the treatment injection, proving that the concept of using a solids-free resin to enhance existing deteriorated barriers is a reliable method. This epoxy resin system helped the operator to regain the well integrity and production in the shortest time without expensive well intervention operations. Epoxy resin based systems have been identified as a novel solution to remediate barrier integrity for well construction and workover operations, hence such case histories with enhanced operations procedures are helpful in increasing awareness of the benefits that can be attained in challenging high-pressure, low-injectivity environments, and can improve well economics.
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Huang, Yingjun, Xudong Liao, Guoyun Bai, Bo Li, and Miao Lou. "Research on Helium Mass-spectrometer Back Pressure Leak Detection Purification Craft for the Specimen with Epoxy Resin." In 6th International Conference on Mechatronics, Materials, Biotechnology and Environment (ICMMBE 2016). Paris, France: Atlantis Press, 2016. http://dx.doi.org/10.2991/icmmbe-16.2016.19.
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HARRISON, KHARI, KALYAN RAJ KOTA, JACOB A. ROGERS, PAUL T. MEAD, ANIKET MOTE, WARUNA D. KULATILAKA, and THOMAS E. LACY, JR. "HYPERVELOCITY IMPACT RESPONSE OF STITCHED CFRP LAMINATES." In Thirty-sixth Technical Conference. Destech Publications, Inc., 2021. http://dx.doi.org/10.12783/asc36/35800.
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In this study, hypervelocity impact experiments were performed on both unstitched and through-thickness Vectran™-stitched laminates. Both laminate types were fabricated from DMS-2436 class-72 warp-knit multiaxial carbon fabric, infused with API-1078 resin using a Controlled Atmospheric Pressure Resin Infusion (CAPRI) process. The laminates were impacted by 4 mm diameter, spherical, Nylon 6/6 projectiles at nominal velocities of 4 km/s using a two-stage light gas gun. The primary measures of the performance of the composite at protecting against impact were in plane hole damage areal comparisons and the comparison of the target back-face debris cloud (BFDC) velocities relative to the incoming projectile velocities. Additional post-shot forensics include characterization of damage morphology and analysis of high-speed videos. Initial inferences about the damage produced in the laminate indicate that the Vectran™ stitching can effectively arrest in-plane damage propagation; impacts at or near a stitchline resulted in no damage propagation across the stitchline boundaries.
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Soltani, Faezeh, and Souran Manoochehri. "A Neural Network-Based Prediction of the Weld Lines in Resin Transfer Molded Parts." In ASME 1999 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/detc99/dac-8623.
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Abstract A model is developed to predict the weld lines in Resin Transfer Molding (RTM) process. In this model, the preforms are assumed to be thin flat with isotropic and orthotropic permeabilities. The position of the weld lines formed by multiple specified inlet ports are predicted using a neural network-based back propagation algorithm. The neural network was trained with data obtained from simulation and actual molding experimentation. Part geometry is decomposed into smaller sections based on the position of the weld lines. The variety of preforms and processing conditions are used to verify the model. Applying the neural networks reduced the amount of computational time by several orders of magnitude compared with simulations. The models developed in this study can be effectively utilized in iterative optimization methods where use of numerical simulation models is cumbersome.
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MASSEY, JUSTIN, BARRETT ROMASKO, and HYONNY KIM. "IMPACT DAMAGE AND INJECTION REPAIR STRENGTH RESTORATION." In Thirty-sixth Technical Conference. Destech Publications, Inc., 2021. http://dx.doi.org/10.12783/asc36/35885.
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Impact damage to composite structures can lead to a range of damage modes. Of interest is modest damage composed of delaminations less than 50 mm in size, and no visible impact-side fiber breakage. While resin injection is a current-practice repair technique that can be used to address these damage modes in a manner that is much less invasive than bonded scarf patch repair, the injection technique is not currently credited as one restoring strength back to laminate. Issues of quantifying the removal of any internal contamination, assessing degree of resin fill, and demonstration of how much strength is restored are being addressed within the scope of this research activity. Resin injection will be conducted and the resulting strength restoration assessed in local fracture tests (end-notch flexure). The formation of actual impact damage morphologies, namely multiple planes of delamination interconnected with matrix cracks, is a critical aspect of this problem. Three 25-ply composite panel types having varying percentage of 0o fiber content have been impacted under low velocity at a range of energy levels. Resulting force vs. time and ultrasonic mapping of damage extent. Damage produced by such impacts will be used in subsequent injection repair studies. Intentional contamination will be introduced, and then removal will be achieved via injected solvents and atmospheric plasma, with monitoring of contaminant presence achieved by in-line quantitative chemical analysis.
Reports on the topic "Bark resin"
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Castellano, Mike J., Abraham G. Shaviv, Raphael Linker, and Matt Liebman. Improving nitrogen availability indicators by emphasizing correlations between gross nitrogen mineralization and the quality and quantity of labile soil organic matter fractions. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597926.bard.
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A major goal in Israeli and U.S. agroecosystems is to maximize nitrogen availability to crops while minimizing nitrogen losses to air and water resources. This goal has presented a significant challenge to global agronomists and scientists because crops require large inputs of nitrogen (N) fertilizer to maximize yield, but N fertilizers are easily lost to surrounding ecosystems where they contribute to water pollution and greenhouse gas concentrations. Determination of the optimum N fertilizer input is complex because the amount of N produced from soil organic matter varies with time, space and management. Indicators of soil N availability may help to guide requirements for N fertilizer inputs and are increasingly viewed as indicators of soil health To address these challenges and improve N availability indicators, project 4550 “Improving nitrogen availability indicators by emphasizing correlations between gross nitrogen mineralization and the quality and quantity of labile organic matter fractions” addressed the following objectives: Link the quantity and quality of labile soil organic matter fractions to indicators of soil fertility and environmental quality including: i) laboratory potential net N mineralization ii) in situ gross N mineralization iii) in situ N accumulation on ion exchange resins iv) crop uptake of N from mineralized soil organic matter sources (non-fertilizer N), and v) soil nitrate pool size. Evaluate and compare the potential for hot water extractable organic matter (HWEOM) and particulate organic matter quantity and quality to characterize soil N dynamics in biophysically variable Israeli and U.S. agroecosystems that are managed with different N fertility sources. Ultimately, we sought to determine if nitrogen availability indicators are the same for i) gross vs. potential net N mineralization processes, ii) diverse agroecosystems (Israel vs. US) and, iii) management strategies (organic vs. inorganic N fertility sources). Nitrogen availability indicators significantly differed for gross vs. potential N mineralization processes. These results highlight that different mechanisms control each process. Although most research on N availability indicators focuses on potential net N mineralization, new research highlights that gross N mineralization may better reflect plant N availability. Results from this project identify the use of ion exchange resin (IERs) beads as a potential technical advance to improve N mineralization assays and predictors of N availability. The IERs mimic the rhizosphere by protecting mineralized N from loss and immobilization. As a result, the IERs may save time and money by providing a measurement of N mineralization that is more similar to the costly and time consuming measurement of gross N mineralization. In further search of more accurate and cost-effective predictors of N dynamics, Excitation- Emission Matrix (EEM) spectroscopy analysis of HWEOM solution has the potential to provide reliable indicators for changes in HWEOM over time. These results demonstrated that conventional methods of labile soil organic matter quantity (HWEOM) coupled with new analyses (EEM) may be used to obtain more detailed information about N dynamics. Across Israeli and US soils with organic and inorganic based N fertility sources, multiple linear regression models were developed to predict gross and potential N mineralization. The use of N availability indicators is increasing as they are incorporated into soil health assessments and agroecosystem models that guide N inputs. Results from this project suggest that some soil variables can universally predict these important ecosystem process across diverse soils, climate and agronomic management. BARD Report - Project4550 Page 2 of 249
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Grumet, Rebecca, and Benjamin Raccah. Identification of Potyviral Domains Controlling Systemic Infection, Host Range and Aphid Transmission. United States Department of Agriculture, July 2000. http://dx.doi.org/10.32747/2000.7695842.bard.
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Potyviruses form one of the largest and most economically important groups of plant viruses. Individual potyviruses and their isolates vary in symptom expression, host range, and ability to overcome host resistance genes. Understanding factors influencing these biological characteristics is of agricultural importance for epidemiology and deployment of resistance strategies. Cucurbit crops are subject to severe losses by several potyviruses including the highly aggressive and variable zucchini yellow mosaic virus (ZYMV). In this project we sought to investigate protein domains in ZYMV that influence systemic infection and host range. Particular emphasis was on coat protein (CP), because of known functions in both cell to cell and long distance movement, and helper component-protease (HC-Pro), which has been implicated to play a role in symptom development and long distance movement. These two genes are also essential for aphid mediated transmission, and domains that influence disease development may also influence transmissibility. The objectives of the approved BARD project were to test roles of specific domains in the CP and HC-Pro by making sequence alterations or switches between different isolates and viruses, and testing for infectivity, host range, and aphid transmissibility. These objectives were largely achieved as described below. Finally, we also initiated new research to identify host factors interacting with potyviral proteins and demonstrated interaction between the ZYMV RNA dependent RNA polymerase and host poly-(A)-binding protein (Wang et al., in press). The focus of the CP studies (MSU) was to investigate the role of the highly variable amino terminus (NT) in host range determination and systemic infection. Hybrid ZYMV infectious clones were produced by substituting the CP-NT of ZYMV with either the CP-NT from watermelon mosaic virus (overlapping, but broader host range) or tobacco etch virus (TEV) (non- overlapping host range) (Grumet et al., 2000; Ullah ct al., in prep). Although both hybrid viruses initially established systemic infection, indicating that even the non-cucurbit adapted TEV CP-NT could facilitate long distance transport in cucurbits, after approximately 4-6, the plants inoculated with the TEV-CPNT hybrid exhibited a distinct recovery of reduced symptoms, virus titer, and virus specific protection against secondary infection. These results suggest that the plant recognizes the presence of the TEV CP-NT, which has not been adapted to infection of cucurbits, and initiates defense responses. The CP-NT also appears to play a role in naturally occurring resistance conferred by the zym locus in the cucumber line 'Dina-1'. Patterns of virus accumulation indicated that expression of resistance is developmentally controlled and is due to a block in virus movement. Switches between the core and NT domains of ZYMV-NAA (does not cause veinal chlorosis on 'Dina-1'), and ZYMV-Ct (causes veinal chlorosis), indicated that the resistance response likely involves interaction with the CP-NT (Ullah and Grumet, submitted). At the Volcani Center the main thrust was to identify domains in the HC-Pro that affect symptom expression or aphid transmissibility. From the data reported in the first and second year report and in the attached publications (Peng et al. 1998; Kadouri et al. 1998; Raccah et al. 2000: it was shown that: 1. The mutation from PTK to PAK resulted in milder symptoms of the virus on squash, 2. Two mutations, PAK and ATK, resulted in total loss of helper activity, 3. It was established for the first time that the PTK domain is involved in binding of the HC-Pro to the potyvirus particle, and 4. Some of these experiments required greater amount of HC-Pro, therefore a simpler and more efficient purification method was developed based on Ni2+ resin.