The composites industry can be positively influenced by composite materials that are processed faster, are lighter in weight, are higher in stiffness and strength, and that are more recyclable. There has been considerable interest in the use of thermotropic liquid crystalline polymers (TLCPs) to reinforce thermoplastic materials. In a novel process developed by Baird and coworkers, wholly thermoplastic composites are produced via a patented, dual extrusion process. This unique process yields a fiber which consists of numerous continuous fibrils of the liquid crystalline polymer encased in a thermoplastic matrix. These fibers have been used to form random mats and woven pre-forms, which have then been compression molded to form composite parts. Because of the high cost associated with these thermotropic liquid crystalline polymers and the desire to generate recyclable composites, a process was developed in this research to separate the liquid crystalline component from polypropylene (PP) composites. The overall objectives of this work were to develop a process to reclaim the liquid crystalline component of these thermoplastic composites, to determine the effect the process had on the properties of the reclaimed liquid crystalline polymer, and finally to determine whether or not the reclaimed liquid crystalline polymer could be used again to generate a reinforcing component. An ancillary objective was to see if the polypropylene could also be reclaimed, and if it had further use as a polymeric resin. In the present work, a novel process was developed that allows the liquid crystalline component to be reclaimed for further use in the composite material or in other applications that require thermotropic liquid crystalline polymers. The polypropylene component, which has undergone molecular weight reduction, can also be reclaimed by this process. This process consisted of using an organic peroxide and reactive extrusion to selectively degrade only the polypropylene, and not the thermotropic liquid crystalline polymer. The degraded polypropylene was selectively dissolved away from the liquid crystalline polymer by stirring the extruded melt in boiling mineral oil. The remaining solids, of thermotropic liquid crystalline polymer, were collected via centrifugation, cleaned of the mineral oil by boiling in kerosene, and then dried in a convection oven. The purity of the reclaimed thermotropic liquid crystalline polymer was determined by density measurements, while the physical properties of the reclaimed material were determined by rheological tests. The mechanical properties were determined via Instron testing of injection molded plaques made from mixtures of reclaimed material and pure thermotropic liquid crystalline polymer. From this work, it was found that over 70 wt% of the thermotropic liquid crystalline polymer, DuPont HX8000, could be successfully separated from the polypropylene to a degree of 96.0%. From Instron testing, it was found that up to 40 wt% of the reclaimed HX8000 could be blended with the pure HX8000, with no loss in mechanical properties. Furthermore, it was seen that up to 83 % of the HX8000 component (40 wt%) of PP 6523 (60 wt%) composites could be replaced with reclaimed HX8000 without seeing any losses in mechanical properties. It was also found that the degraded polypropylene could be successfully separated, via centrifugation at a temperature of 253 K, and could be potentially used as resin for non-wovens. The projected material cost of the reclaimed HX8000, based on the ability to purchase and to process in bulk, was determined to be 90 % less than the virgin HX8000. / Master of Science

No description available.

No description available.

An important criteria for optimising hydraulic systems is their size. Especially for tanks and heat exchangers oil parameters as heat capacity and thermal conductivity have a big influence on the size. Additionally, various oils differ in their parameters. Accordingly, the heat capacity and thermal conductivity need to be known. However, little research has been done. Data-sheets usually do not provide any thermal data. In this paper, the thermal conductivity is measured for varying types of hydraulic oils. The thermal conductivity is determined by a newly designed test-rig measuring the radial temperature difference in a tube at a quasi-static state using a constant heat flux. Thus, an overview over the thermal conductivity of different oils is achieved. Based on the results, a comparison between different types of fluid is made.

A alta ocorrência da doença periodontal nos cães, seu impacto na saúde sistêmica e a possibilidade de prevenção pela combinação de técnicas fazem da afecção alvo de estudos sobre novos métodos adjuvantes de tratamento que sejam isentos de efeitos colaterais. O objetivo do presente estudo foi avaliar a utilização de óleo mineral ozonizado sob apresentação de pomada em terapia preventiva à doença periodontal de cães hígidos, tendo-se em vista as características físico-químicas da molécula de ozônio, que inibem a formação da placa dentária sem causar danos teciduais por sua biocompatibilidade às células da mucosa oral. Os cães (n=32) foram avaliados quanto à presença de sinais de periodontite e submetidos ao tratamento periodontal convencional com raspagem e polimento dentário. Foram divididos em cinco grupos terapêuticos, sendo estes diferidos quanto à frequência semanal de aplicação tópica de ozônio (uma, duas, três ou seis vezes) ou aplicação de placebo. Avaliações clínicas foram realizadas após sete dias de tratamento (T7). A análise de placa foi realizada por método clínico e computadorizado. A análise computadorizada evidenciou diferenças não identificadas pela análise clínica por avaliador único. Para ambos, o tratamento periodontal convencional associado à ozonioterapia diária ou em dias alternados mostrou os melhores resultados antiplaca. Cita-se a possibilidade de ação residual da molécula em óleo mineral pelos resultados positivos obtidos em dentes de difícil acesso em domicílio. Não houve indícios de sinais de toxicidade durante o estudo. Em conclusão, os resultados mostram que a aplicação tópica de pomada de óleo mineral ozonizado atua de forma adjuvante ao tratamento periodontal convencional na prevenção da formação de placa dentária com melhores resultados após uso diário. A ozonioterapia mostrou-se como método terapêutico adjuvante atraumático, rápido e eficiente na prevenção da instalação da doença periodontal em cães hígidos. / The high occurrence of periodontal disease in dogs, its impact on systemic health and the possibility of its prevention by the combination of techniques make this disease a target of many studies about new adjuvant treatment methods that are free of side effects. The objective of the present study was to evaluate the use of ozonized mineral oil under ointment presentation as a preventive therapy to the periodontal disease of healthy dogs, considering the physicochemical characteristics of the ozone molecule, which inhibit the formation of dental plaque without causing tissue damage due to its biocompatibility to oral mucosa cells. Dogs (n = 32) were evaluated for signs of periodontitis and submitted to conventional periodontal treatment with scaling and dental polishing. They were divided into five therapeutic groups, which were deferred to the weekly frequency of topical application of ozone (one, two, three or six times) or placebo application. Clinical evaluations were performed after seven days of treatment (T7). Plaque analysis were performed by clinical and computerized methods. The computerized analysis evidenced differences not identified by the clinical analysis by single evaluator. For both, conventional periodontal treatment associated with daily or alternate daytime ozonation showed the best antiplaque results. It is mentioned the possibility of residual action of the molecule in mineral oil by the positive results obtained in teeth that have hard access at home. There were no signs of toxicity during the study. In conclusion, the results show that the topical application of ozonated mineral oil ointment adjusts to conventional periodontal treatment in the prevention of dental plaque formation with better results after daily use. Ozone therapy has proved to be an atraumatic, fast and efficient adjuvant therapeutic method to prevent the installation of periodontal disease in healthy dogs.

"The performance of a series of mineral oil based quenchants has been investigated using the CHTE Quench Probe System and probe tips of 4140 steel to determine the cooling rate, heat transfer coefficient, Hardening Power (HP) and Tamura’s V indices in terms of the physical properties of quenchants; e.g. viscosity and oil start temperature. The Quench Factor, Q, was also calculated in terms of the hardness of the quenched parts. The lumped parameter approximation was used to calculate the heat transfer coefficient as a function of temperature during quenching. The results revealed that the maximum cooling rate increases with decrease in quenchant viscosity. As viscosity increases, Tamura’s V is nearly constant, while the HP decreases. For the selected oils, cooling ability of quenching oil increases with the increase in oil operating temperature, reaches a maximum and then decreases. The heat transfer coefficient increases with the increase in hardening power and maximum cooling rate. As the viscosity increases, the quench factor increases, which indicates the cooling ability of the oil decreases since the higher quench factor means the lower cooling ability of the oil. The hardness decreases with the increase in quench factor. Also the effect of surface oxides during quenching in commercial oils is studied. It was found that for 4140 steel probes the formation of oxide in air increases the cooling rate and heat transfer coefficient, the cooling rate curve of 4140 steel probe heated in argon shows clear Leidenfrost temperature, the oxide layer may require a significant thickness to cause the decrease in heat transfer coefficient. For 304 stainless steel probes the cooling rate and heat transfer coefficient are quite similar in air and in argon."

Beim Kolikpferd stellt der Einsatz von Laxantien den wesentlichen Teil der konservativen Behandlung primärer Obstipationen des Zäkums und großen Kolons dar. Um die Obstipation zu erreichen muss das über eine Nasenschlundsonde eingegebene Abführmittel den Magen verlassen und den Dünndarm passieren. Dabei soll das Flüssigkeitsvolumen möglichst vollständig im Intestinaltrakt verbleiben, um effektiv die Ingesta zu durchfeuchten und so die Obstipation zu lösen. Je nach Art und Konzentration des gewählten Laxans werden Resorptions- und Sekretionsvorgänge an der Darmschleimhaut ausgelöst, die sich als Elektrolytverschiebungen oder Alterationen des Wasserhaushaltes im Blut zeigen können. Ziel dieser Studie war es, beim gesunden Pferd einen Einfluss der am häufigsten eingesetzten Laxantien auf die Magenentleerungszeit zu ermitteln. Zudem sollten Auswirkungen auf den Elektrolyt- und Wasserhaushalte untersucht werden. Für die vorliegende Studie wurde sechs gesunden, nüchternen, adulten Warmblutpferden abwechselnd je eines von 5 Laxantien über eine Nasenschlundsonde in den nüchternen Magen eingegeben: 1,8% Natriumsulfatlösung (Protokoll 1); 4,2% Magnesiumsulfatlösung (Protokoll 2); Paraffinöl (Protokoll 3); 25% Natriumsulfatlösung (Protokoll 4); 25% Magnesiumsulfatlösung (Protokoll 5). Als Kontrolle wurde Wasser verabreicht: 10 L Wasser (Protokoll 6); 2 L Wasser (Protokoll 7). Zur indirekten Messung der Magenentleerung wurde der flüssige Passagemarker D-(+)-xylose (0,5 g/kg KG als 10% Lösung) jedem Protokoll zugefügt mit mindestens einer Woche Auswaschzeit zwischen den einzelnen Protokollen. Zu festgelegten Zeitpunkten wurden EDTA-Blut- und Serumproben aus der Jugularvene entnommen. Die Serumkonzentration von D-Xylose wurde colorimetrisch untersucht. Die Zeit bis zum Erreichen der maximalen Serumkonzentration von D-Xylose (Tmax) wurde als Magenentleerungszeit angesehen. Zur Einschätzung des Wasserhaushaltes wurden Totalprotein, Albumin und Hämatokrit bestimmt. Der Elektrolythaushalt wurde anhand der Serumkonzentrationen von Natrium, Kalium, Chlorid, Magnesium und Gesamtkalzium beurteilt. Zudem wurde der Einfluss auf die Wasseraufnahme und die Kotkonsistenz grobsinnlich untersucht. Ergebnisse dieser Studie zeigen, dass weder isotone Natriumsulfatlösung noch Paraffinöl die Magenentleerungszeit im Vergleich zu Wasser beeinträchtigen. Isotone Magnesiumsulfatlösung als auch hypertone Lösungen salinischer Laxantien führen zu einer signifikanten Verzögerung der Magenentleerung im Vergleich zu Wasser. Nach 10-stündiger Nahrungskarenz führte die Applikation von Wasser bei gesunden Pferden zum Abfall der Serumkonzentrationen von Natrium, Kalium, Magnesium, Gesamtkalzium und Chlorid. Isotone Lösungen von Natriumsulfat (1,8%) und Magnesiumsulfat (4,2%) führten nach einmaliger Applikation zum signifikanten Anstieg der Serumkonzentrationen von Natrium bzw. Magnesium innerhalb der Referenzbereiche. Paraffinum liquidum hatte keine starke Alterationen des Elektrolythaushaltes zur Folge. Hypertone Natriumsulfatlösung (25%) verursachte Hypernatriämie sowie einen signifikanten Abfall der Kalium- und signifikanten Anstieg der Chloridkonzentration. Hypertone Magnesiumsulfatlösung (25%) verursachte Hypermagnesämie sowie eine signifikante Abnahme der Kalium- und Gesamtkalziumkonzentration. Keines der verabreichten Laxantien führte zur Dehydratation. Alterationen der Wasseraufnahme oder der Kotkonsistenz wurden ausschließlich durch hypertone Natriumsulfatlösung verursacht, die die Wasseraufnahme deutlich steigerte und vorübergehend dünnbreiigen Kotabsatz induzierte. Bei primären Obstipationen des großen Kolons muss bis zur Lösung der Obstipation meist eine mehrmalige Applikation von Abführmitteln erfolgen. Hypertone Natrium- bzw. Magnesiumsulfatlösung erhöht die Serumkonzentration von Natrium bzw. Magnesium signifikant und könnte eine klinische Hypernatriämie bzw. Hypermagnesiämie erzeugen. Aus diesem Grund sind isotone Lösungen zu bevorzugen. Außerdem ist Kolikpferden mit primärer Dickdarmobstipation, die mit salinischen Laxantien behandelt werden, freier Zugang zu Wasser zu gewähren, um den entstehenden Durst der Pferde zu stillen. Zusammenfassend ist die Verabreichung isotoner Natriumsulfatlösung zu empfehlen, weil dieses effektive Laxans weder die Magenentleerungszeit verzögert, noch starke Elektrolytimbalanzen verursacht. / The use of laxatives is crucial in the treatment of horses with cecal or large colon impaction. To reach the impacted mass, the laxative must leave the stomach and pass through the small intestine. The fluid volume should stay inside the gastro-intestinal tract to soften the intestinal contents and resolve the impaction. Depending on the type and concentration of the laxative, absorption and secretion can be triggered in the intestinal mucosa which might be shown as electrolyte abnormalities, or as alterations in the water balance in the blood. The aim of this study was to determine an influence of the most frequently used saline and lubricant laxatives on gastric emptying time in healthy horses. Furthermore the effect on electrolyte and water balance was to be investigated. Six healthy adult fasted Warmblood horses were used for this study which was performed with 5 laxatives, administered via nasogastric tube: 1.8% sodium sulfate (trial 1), 4.2% magnesium sulfate (trial 2), mineral oil (trial 3), 25% sodium sulfate (trial 4), 25% magnesium sulfate (trial 5). Water was used as control: 10 L water (trial 6), 2 L water (trial 7). For indirect measurement of gastric emptying the liquid passage marker D-(+)-xylose (0.5 g/kg bwt as 10% solution) was added to each trial with a minimum washout period of at least one week between the individual trials. EDTA blood and serum samples were taken from the jugular vein at predetermined time points. The serum concentration of D-xylose was analyzed colorimetrically. The time to reach peak serum concentration of D-xylose (Tmax) was considered as gastric emptying time. Total protein, albumin and PCV were chosen to evaluate water balance. Electrolyte balance was evaluated on the basis of the serum concentrations of sodium, potassium, chloride, magnesium and total calcium. Furthermore the impact on water uptake and fecal consistency was roughly examined. Isotonic solutions of sodium sulfate as well as mineral oil do not delay gastric emptying time compared to water. Isotonic solutions of magnesium sulfate as well as hypertonic solutions of saline cathartics significantly delay gastric emptying time in comparison to water. After ten hours of food restriction the administration of water decreased the serum concentrations of sodium, potassium, magnesium, total calcium and chloride in healthy horses. A single administration of isotonic solution of sodium sulfate (1.8%) or magnesium sulfate (4.2%) significantly increased serum sodium, respectively serum magnesium concentrations, within the reference range. Mineral oil did not alter electrolyte balance. Hypertonic solution of sodium sulfate (25%) caused hypernatremia, a significant decrease in potassium concentration and a significant increase in chloride concentration. Hypertonic solution of magnesium sulfate (25%) caused hypermagnesemia and a significant decrease in potassium and total calcium concentrations. None of the administered laxatives caused dehydration. Altered water uptake or fecal consistency was caused by hypertonic solution of sodium sulphate only, which considerably increased water consumption and transitionally induced runny feces. For treatment of simple large colon impactions, administration of laxatives usually has to be repeated, until the obstruction has resolved. Hypertonic solutions of sodium and magnesium sulfate significantly increase serum sodium or magnesium concentrations, respectively and may cause clinically hypernatremia or hypermagnesemia. Therefore isotonic solutions are preferable. Furthermore horses with simple large colon impaction, which are treated with saline cathartics need to have free access to water in order to satisfy their arising thirst. In summary it can be stated that the administration of isotonic solution of sodium sulfate is to be recommended, since this effective laxative does neither delay gastric emptying time nor leads to severe electrolyte alterations.

In general,the lubricants were composed by basestock and additive,and the basestock is usual use mineral oil. This paper examines the viscosity,viscosity index and antiwear properties of palm oil blended lubricants. To study the feasibility of using palm oil as the lubricant of automative engine . The V.I. of commercial sae 30 engine oil will increase from 101 to 147 via the blend of palm oil and SAE 30.The anti-wear charactisteristics test in a four-ball tribometer.Under conditions of 40kg,1200rpm,and a test duration of one hour at 120 ¢J. The test oil appear markedly superior to the reference SAE 30 engine oil .The palm oil blended lubricant showed is reduced to 10% scar than reference oil .

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.

Este trabalho investigou a incorporação de um resíduo da indústria petroquímica de rerrefino de óleos minerais, uma argila contaminada com hidrocarbonetos, como matéria-prima para a indústria cerâmica tradicional. O resíduo foi incorporado a uma massa cerâmica com o objetivo de obter produtos de cerâmica vermelha. As matérias-primas utilizadas foram caracterizadas quanto à composição mineralógica, química e granulométrica. Neste estudo, foram realizadas formulações com 0%, 3%, 5%, 10% e 15% em massa de resíduo para a obtenção dos corpos-de-prova. Os corpos-de-prova obtidos foram sinterizados nas temperaturas de 1000°C, 1050°C, 1100°C, 1150°C. Foram avaliadas as seguintes propriedades tecnológicas: absorção de água, porosidade aparente, retração linear de queima e resistência à flexão a quatro pontos. Os resultados obtidos mostraram que a incorporação de resíduo na massa cerâmica apresentou melhor desempenho nas suas propriedades tecnológicas, enquadrando-se a normas para produtos cerâmicos tradicionais, como telhas, blocos cerâmicos e pisos de revestimentos. Em consideração ao aspecto ambiental, as amostras foram submetidas aos ensaios de lixiviação, solubilização e emissões gasosas. Nos testes de lixiviação não foram encontrados elementos que a classificassem como resíduo perigoso de acordo com a NBR 10.004. Nos ensaios de solubilização, todas as composições com adição de resíduo na temperatura de 1000°C foram classificadas como resíduo classe II A – não inertes, enquanto a 1150°C foram classificadas como resíduo classe IIB- inertes. Em relação às emissões gasosas, estas apresentaram baixas concentrações dos elementos zinco, sódio, cálcio e silício na água coletada durante a queima. Os resultados indicaram a possibilidade de utilização deste resíduo na produção de cerâmica vermelha. / This work investigated the incorporation of a waste of the petrochemical industry of mineral oils rerefining, a clay contaminated with hydrocarbons, as raw material to traditional ceramic industry. The waste was incorporated into the ceramic mass to obtain red ceramics products. The raw material was characterized by the mineralogical, chemical and granulometric composition. In this study were incorporated 0, 3, 5, 10 and 15 % waste weight to formulate the samples. The samples were sintered at temperatures 1000°C, 1050°C, 1100°C and 1150°C. The technological properties evaluated were: water absorption, apparent porosity, linear shrinkage and flexural rupture strength by the four point test. The results obtained showed that the waste added to the ceramic mass contributed to improve the quality of the ceramic samples. In the environmental aspects, the samples were submitted to leaching and solubilization tests and gaseous emissions. In the leaching test samples did not present elements classified as dangerous, according to NBR 10004. In the solubilization test, all compositions with waste, sintered at 1000°C, were classified as class IIA -not inert and at 1150°C class IIB - inert. The gaseous emissions demonstrated low concentration of the elements: zinc, sodium, calcium, and silicium in the water collected during the sinterization process. The results indicated the possibility of using this waste in the red ceramic production.