Influence of the final temperature of investment healting on the tensile strength and Vickers hardness of CP TI and TI-6AL-4V alloy

The aim of the work was to evaluate the influence of the temperature of investment healting on the tensile strength and Vickers hardness of CP Ti and Ti-6Al-4V alloy casting. Were obtained for the tensile strength test dumbbell rods that were invested in the Rematitan Plus investment and casting in the Discovery machine cast. Thirty specimens were obtained, fiftten to the CP Titanium and fifteen to the Ti-6Al-4V alloy, five samples to each an of the three temperatures of investment: 430°C (control group), 480°C and 530°C. The tensile test was measured by means of a universal testing machine, MTS model 810, at a strain of 1.0 mm/min. After the tensile strenght test the specimens were secctioned, embedded and polished to hardness measurements, using a Vickers tester, Micromet 2100. The means values to tensile tests to the temperatures 430°C, 480 and 530: CP Ti (486.1 - 501.16 - 498.14 -mean 495.30 MPa) and Ti-6Al-4V alloy (961.33 - 958.26 - 1005.80 - mean 975.13 MPa) while for the Vickers hardness the values were (198.06, 197.85, 202.58 - mean 199.50) and (352.95, 339.36, 344.76 - mean 345.69), respectively. The values were submitted to Analysis of Variance (ANOVA) and Tukey' s Test that indicate differences significant only between the materials, but not between the temperature, for both the materias. It was conclued that increase of the temperature of investment its not chance the tensile strength and the Vickers hardness of the CP Titanium and Ti-6Al-4V alloy.

In vitro assessment of pulp chamber temperature of different teeth submitted to dental bleaching associated with LED/laser and halogen lamp appliances

This study sought to assess the pulp chamber temperature in different groups of human teeth that had been bleached using hydrogen peroxide gel activated with halogen lamps or hybrid LED/laser appliances. Four groups of ten teeth (maxillary central incisors, mandibular incisors, mandibular canines, and maxillary canines) were used. A digital thermometer with a K-type thermocouple was placed inside pulp chambers that had been filled with thermal paste. A 35% hydrogen peroxide-based red bleaching gel was applied to all teeth and photocured for a total of three minutes and 20 seconds (five activations of 40 seconds each), using light from an LED/laser device and a halogen lamp. The temperatures were gauged every 40 seconds and the data were analyzed by three-way ANOVA, followed by Tukey's test. Regardless of the light source, statistically significant differences were observed between the groups of teeth. The mean temperature values (±SD) were highest for maxillary central incisors and lowest for mandibular canines. The halogen lamp appliance produced more pulp chamber heating than the LED/laser appliance. The increase in irradiation time led to a significant increase in temperature.

Sperm motility of Prochilodus lineatus in relation to dilution rate and temperature of the activating medium

The objective of this study was to assess the effects of an activating solution on the sperm motility duration (SMD) of 'curimbatá', Prochilodus lineatus through of the definition of qualitative and quantitative parameters of the semen pool used in the experiment; evaluation of the effects of different ratios of semen dilution corresponding to 1-:-1, 1-:-2, 1-:-20, 1-:-200, 1-:-2000, 1-:-20-000 and 1-:-100-000 semen:dilute solution on the SMD and, assessment of the effects of different temperatures of the activating solution (5, 10, 15, 20, 25, 30, 35, 40, 45 and 50°C) on the SMD. The results of SMD were directly proportional to the dilution (P<0.05), starting from the dilution of 1-:-2 (semen:water), with 23.04-s. Were used three replicates of the semen pool for each test. Two-year-old brookstock were maintained in ponds culture conditions. In November-December 2006, twelve mature males broodfish were selected (mean weight and length of 405.8±134.2-g and 25.6±3.1-cm, respectively). The males released that semen under slight pressure of the urogenital papilla were selected for the experiment. The SMD increased proportionally to the increase in dilution, until it reached a maximum of 28.83-s for the ratio 1-:-100-000 semen: dilute solution. The results of SMD in relation to the temperature of the activating solution exhibited a quadratic behavior (P<0.05) with a maximum theoretical performance in terms of sperm motility duration of 21.36-s at a temperature of 17.3°C. Thus, for the species considered, the increase in the dilution ratio proved favorable for the rise in motility duration until the maximum value studied of 1-:-100-000 semen:dilute solution. As for the temperature of the activating solution, the best results of SMD were obtained at the temperature of 17.3°C. At higher temperatures used in the experiment (25, 30, 35, 40, 45 and 50°C), a decrease in motility duration. © 2010 Blackwell Verlag, Berlin.

Effect of occlusal splint treatment on the temperature of different muscles in patients with TMD

Purpose: The aim of this study was to evaluate the effect of occlusal splint treatment on the temperature of masseter (inferior, intermediate and superior), anterior temporal, digastric and trapezius muscles in patients with temporomandibular disorder (TMD). Materials and methods: Thirty patients (6 male and 24 female) aged from 16 to 57 years (mean 37.8. ± 11.4 years) were selected. The patients were diagnosed with muscular TMD by clinical examination (application of Research Diagnostic Criteria questionnaire and physical examination). Occlusal splints in acrylic resin were inserted in all patients with a weekly follow-up. The superficial thermography (°C) on the both sides of the muscles was performed using a digital thermometer in a controlled temperature room. This procedure was performed before occlusal splint insertion (patient with pain) and after the completion of the treatment (patient without pain). The data were analyzed by 2-way repeated-measures ANOVA and means were compared by Tukey HSD test (P< .05). Results: After occlusal splint treatment a significant increase in temperature was observed in each muscle, both in the right and left sides. When the muscles were compared in the same period (before or after therapy) there was no significant difference among them. Conclusion: It can be concluded that the use of occlusal splint promoted a significant increase on the muscles temperature. There was symmetry in the temperature of muscles on the right and left sides both before and after the treatment. © 2010 Japan Prosthodontic Society.

Effect of Storage Time and Temperature of Equine Epididymis on the Viability, Motion Parameters, and Freezability of Epididymal Sperm

The recovery of sperm from the epididymal cauda may be the last chance to obtain genetic material when sudden death or serious injuries occur in valuable stallions. However, the lack of technical knowledge regarding the storage and transportation of the epididymis often prevents the preservation of the sperm. Therefore, the aim of this study was to compare sperm parameters of sperm obtained immediately after orchiectomy with sperm recovered from epididymal cauda at different times after storage at 5°C and at room temperature (RT). For that, 48 stallions of different breeds were used. In group 1 (control group), eight stallions were used, and the harvest of the epididymal sperm was performed immediately after orchiectomy. In group 2, 40 stallions were used, which were divided into five groups according to the storage time of the epididymis after orchiectomy (6, 12, 18, 24, or 30 hours), making a total of eight stallions per group. One epididymis of each stallion was stored at 5°C, and the contralateral epididymis was stored at RT, both for the same period. The sperm parameters of total motility, progressive motility, progressive linear velocity, curvilinear velocity, percentage of rapid sperm, and plasma membrane integrity were evaluated in all the groups after sperm recovery, resuspension in a sperm freezing diluent, and thawing. In conclusion, the storage of the testis-epididymis complex at 5°C provided better preservation of epididymal sperm than the storage at RT, and regardless of the temperature, the progressive motility is the sperm parameter that is most sensitive to storage time. © 2013 Elsevier Inc.

Critical currents and melting temperature of a two-dimensional vortex lattice with periodic pinning

The critical current and melting temperature of a vortex system are analyzed. Calculations are made for a two-dimensional film at finite temperature with two kinds of periodic pinning: hexagonal and Kagomé. A transport current parallel and perpendicular to the main axis of the pinning arrays is applied and molecular dynamics simulations are used to calculate the vortex velocities to obtain the critical currents. The structure factor and displacements of vortices at zero transport current are used to obtain the melting temperature for both pinning arrays. The critical currents are higher for the hexagonal pinning lattice and anisotropic for both pinning arrays. This anisotropy is stronger with temperature for the hexagonal array. For the Kagomé pinning lattice, our analysis shows a multi stage phase melting; that is, as we increase the temperature, each different dynamic phase melts before reaching the melting temperature. Both the melting temperature and critical currents are larger for the hexagonal lattice, indicating the role for the interstitial vortices in decreasing the pinning strength. © 2012 Springer Science+Business Media New York.

Study of the glass transition temperature of as-s glasses for the fabrication of chalcogenide optical fibers

Values of glass transition temperature (Tg) and of linear expansion coefficient (α) for Asx S100-x glasses were measured in the range of concentrations 35 × 42. Because of the importance of the glass formation region 35 × 42 for the optical fibers elaboration, special attention was made on high-pure Asx S100-x glasses. For the glass in the range of 35 × 38, we measure Tg with the interval of x equal to 1 at.% of arsenic. We also measured the Tg values with the interval of x equal to 0.5 at.% of As. We obtained nonlinear behavior of Tg, reflecting the change in molecular composition of As-S glass in the glass composition range studied. The control of such parameters is important to produce optical fibers with specific numerical aperture. © 2013 The American Ceramic Society and Wiley Periodicals, Inc.

Study of thermal decomposition of ignition temperature of bagasse, coal and their blends

In Brazil, due to its availability, sugar cane bagasse has a high potential for power generation. The knowledge of ignition behavior, as well as the knowledge of the chemical kinetics, in of fuels combustion process is important features in boilers projects and in the stability of the combustion process control. The aim of this study is to investigate the thermal behavior of sugar cane bagasse, coal and their blends. The methodology proposed by Tognotti et al. (1985) was applied to determine the ignition temperature for all samples. Ignition temperatures were 256oC for neat bagasse and 427oC for neat coal, and 275oC for both blends (50-50% and 25-75%). The ModelFree Kinetics was applied to determine the apparent activation energy (Eα) of the thermal decomposition of sugar cane bagasse. For the two major events of mass loss of bagasse which correspond to the thermal decomposition of organic matter (mainly hemicellulose, cellulose and lignin), average values of Eα were obtained for both combustion and pyrolysis processes. In synthetic air atmosphere, the Eα were 170.8±26.3 kJ⋅mol-1 and 277.8±58.6 kJ⋅mol-1, while in nitrogen atmosphere, the Eα were 185.0 ± 11.4 kJ⋅mol-1 and 82.1±44.4 kJ⋅mol-1. The results obtained can be explained by synergistic effects when both bagasse and coal were blended, changing the fuel reactivity.

Variação da temperatura corpórea em ovinos sob diferentes condições de manejo

Pós-graduação em Ciência Animal - FMVA

Selection of environmental temperature by the yellow scorpion Tityus serrulatus Lutz & Mello, 1922 (Scorpiones, Buthidae)

The preferred temperature of the yellow scorpion Tityus serrulatus was investigated since its dispersion is a matter of concern. Adult T. serrulatus, weighing 1.24 ± 0.20 g (mean + sd) and with a standard length of 59.3 ± 2.5 mm, were used. A metallic corridor (120 cm long, 5 cm large and 10 cm high) with thermal gradient ranging from 0°C to 40°C was used. Tityus serrulatus chose and stayed in temperatures ranging from 14° C to 38°C when safe conditions were offered (dark and thigmotactic stimuli). The number of animals that remained in the 11°C-20°C, 21°C-30°C, and 31°C-40°C temperature zones were 8, 8, and 9, respectively. The chi-square test (degree of freedom = 2) showed that differences were not significant (p>0.05). Some animals moved to lower temperature areas (less than 8°C) when the corridor was completely illuminated and thigmotactic stimuli were absent, which led the animals to present a torpor state. It is concluded that T. serrulatus does not select a specific environmental temperature. Associated with the capacity of temporally surviving at low temperatures, this species seems to be highly adaptable to different thermal zones.

Temperature and thermal regime effects on the specific dynamic action of Bothrops alternatus (Serpentes, Viperidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of Environmental Temperature During the First Week of Brooding Period on Broiler Chick Body Weight, Viscera and Bone Development

O presente trabalho teve como objetivo estudar o efeito de diferentes temperaturas-ambiente durante a primeira semana de vida de pintos de corte sob parâmetros zootécnicos, desenvolvimento visceral e crescimento ósseo. Foram utilizados 240 pintos de um dia, alojados em 3 câmaras climáticas, com temperaturas constantes de 20, 25 e 35°C do 1° ao 7° dia de vida. Diariamente, o consumo de água e ração, bem como o peso vivo, o peso relativo do fígado, moela, coração, saco vitelino e bursa de Fabricius foram avaliados. A tíbia e o fêmur também foram pesados e o comprimento e espessura (diâmetro médio) mensurados. As aves criadas a 20°C ganharam menos peso e consumiram menos ração do que aves mantidas a 25°C e menos água do que aves mantidas a 35°C. O peso relativo do fígado, coração e moela foram afetados pela temperatura ambiente, entretanto, não foi observado efeito da temperatura de criação sobre o peso do saco vitelino e bursa de Fabricius. Os dados mostraram que todos os parâmetros ósseos pesquisados aumentaram com a idade das aves. A temperatura ambiente não afetou a espessura da tíbia e do fêmur, mas foi observado um aumento significativo no peso e comprimento dos ossos com o aumento da temperatura ambiente. Os resultados desse experimento mostraram que o estresse por frio (20°C) reduziu o crescimento ósseo bem como o peso vivo das aves, durante os primeiros sete dias após a eclosão.

Effect of temperature on percentage of germination of canistel seeds (Pouteria campechiana)

O canistel é uma fruteira originada no México e América Central, sendo introduzida no Brasil em 1986. As plantas apresentam porte médio, porém podem atingir até 15 metros de altura; as folhas medem cerca de 10 a 25 cm; as flores são completas e pequenas, e o fruto apresenta coloração amarela quando maduro, com polpa esbranquiçada e sabor doce. A propagação pode ser realizada por semente ou por enxertia. em vista da quase total ausência de informações sobre a cultura e a possibilidade de cultivo comercial, realizou-se o presente trabalho, no qual se avaliou o efeito da temperatura na porcentagem de germinação de sementes. Foi verificado que as melhores taxas foram obtidas à temperatura de 30ºC e as menores a 15ºC, 20ºC e 40ºC, sendo esta última a pior delas.

Temperature during soybean seed storage and the amount of electrolytes of soaked seeds solution

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of the temperature in germination of seeds of jabuticaba tree

A jabuticabeira (Myrciaria spp.) é uma fruteira originada do centro-Sul do Brasil e apresenta tipos diferentes. É uma árvore de tamanho médio, com tendência a formar copa com grande número de ramos desde pouco acima do solo. Uma característica considerada como limitante para a cultura comercial dessa frutífera é o grande período juvenil, aconselhando-se então produzir bons porta-enxertos de pés-francos e enxertar as variedades desejadas, ou ainda por outros processos vegetativos. Objetivando-se avaliar a influência da temperatura na germinação de sementes de três clones de jabuticabeira, realizou-se um experimento em condições de laboratório. Observou-se que há influência da temperatura na porcentagem de germinação, sendo que, nas mais baixas temperaturas (15ºC e 20ºC), foi verificada uma maior porcentagem de germinação para os três clones em estudo. Quando do uso da temperatura de 35ºC, dois clones tiveram apenas 8% de germinação, enquanto, para o outro, foi verificado 35%. Estes dados mostram a possibilidade de ocorrência de variabilidade entre clones de jabuticabeira.