Thermomechanical processing of low carbon bainitic steels is used to obtain a bainitic microstructure with good strength and toughness by continuous cooling after forging without the need of further heat treating, hence reducing manufacturing costs. However, hot forging parameters can significantly influence the microstructure in the forged material. A series of heat treating and forging experiments was carried out to analyze the effect of austenitizing time and temperature on the grain growth and the effect of forging temperature on the Prior Austenite Grain Size (PAGS) and continuously cooled microstructure. The forged microstructures were characterized by optical microscopy, microhardness tests, and X-ray diffraction. The results indicate that at 1200 °C austenitizing temperature abnormal grain growth takes place. Forging temperature significantly affects the PAGS and the subsequently formed microstructure. At high forging temperature (1200 °C), an almost fully bainitic microstructure was obtained. As the forging temperature was reduced to 1100 and 1000 °C, the PAGS refined, while the polygonal ferrite faction increased and the amount of retained austenite decreased. Further evaluations showed that a decrease in the forging temperature results in a higher carbon concentration in solution in the retained austenite leading to a stabilization effect.

The current investigation was conducted on gres porcelain stoneware, a robust, impermeable and aesthetically pleasing type of ceramic mainly used for flooring, characterizing its resistance to bending and low-velocity impact, both representative efforts to which flooring tiles are constantly subjected as a consequence of the fall of objects and microsubsidences. The mechanical characterization was made through experimental tests following an adapted low-velocity impact testing routine, and the model was by validated numerical simulation through the explicit code software LS-DYNA based on the Johnson–Holmquist constitutive material model. Specimens were tested before and after an annealing cycle industrially used to allow porcelain folding. The thermal treatment demonstrated to infer a decrease in mechanical resistance on the material, understood as a consequence of its elevated maximum temperature and fast cooling rate. The numerical model calibrated successfully allows predicting the behavior of gres porcelain before and after annealing against low-velocity impact.

The poly(isobutylcyanoacrylate)cyclodextrin nanoparticles were characterized by the presence of many lipophilic sites belonging to the cyclodextrins which were firmly anchored to the structure of the particles. Therefore, this new type of nanoparticles offers probably an opportunity for increasing the loading of nanoparticles with various lipophilic drugs.

Thermo-mechanical treatments using continuous cooling after forging are an established method for producing bainitic steels, mainly because of the elimination of energy intensive additional heat treatment processes. The cooling is usually employed in an uncontrolled manner in the industrial sector, which can be detrimental to the resulting microstructural morphology and, consequently, to the final product properties. In this study, a new controlled two-step cooling route based on the principles of bainitic displacive growth was designed and applied in a 0.18C (wt-%) steel. Inverse finite element method was used on the cooling data to obtain the evolution of temperatures for the samples during cooling, allowing to assess point to point cooling rates. Investigations via X-ray diffraction, optical microscopy analysis and hardness testing revealed a variation of bainitic morphology, namely, the transition from granular bainite to lath-like bainite with relatively high hardness and constituents/ phase boundaries than the pre-treated microstructure.

Abstract. It is proved that a globally stable complete minimal surface in R} with finite total curvature is a plane.The aim of this note is to give a proof of the following result.Theorem. Let x: M -» R3 be a complete minimal immersion of a two-dimensional, orientable, C00 manifold M. Assume that x is globally stable and that the total curvature of x is finite. Then x(M) c R3 is aplane.Here globally stable means that each compact subdomain W c M is a nondegenerate minimum for the area function of the induced metric for all variations that keep the boundary d W of W fixed. The result is clearly false for minimal surfaces in R4 and we do not know whether it remains true without the finiteness of the total curvature.1Proof. Let S2 c R3 be the unit sphere with center at (0, 0, 0). We first prove that given a finite number of points px, . . . ,pk E S2, there exists a domain D c S2 such that \X(D) = 2, where A, is the first eigenvalue of the Laplacian A in S2, and D omits neighborhoods U¡ c S2 of p,, i = 1, . . ., k. It is easily checked that A«, + 2m, = 0 (cf. [1, p. 519]) and that limz_±1 u¡ = -oo. Furthermore, u¡ is positive in a ring-shaped domain D¡ bounded by two parallels of S2 and vanishes on the boundary dD¡. Thus A,(Z>,) = 2. Now set u = 2*_! w, and define D as a connected component of the set {p G S2; u > 0}. We claim that D is not empty. To see that we use the fact that of all spherical domains with the same area, the spherical cap has the smallest eigenvalue [3]. Since Dx n D2 =£ 0, a connected component Dx2 of the set {p G S2; ux + u2> 0} has eigenvalue 2. By the above, and the fact that the hemisphere has eigenvalue 2, we conclude that A(DX2) > 2ir, where A( ) denotes the area of the enclosed domain. By the same token, A(D¡) > 2ir; hence DX2 n D3 ^ 0. An easy induction now shows that A(D) > 2ir, as we claimed. Thus XX(D) = 2 and, since hm^^ u = -oo, D omits neighborhoods U¡ of p" as we wished to prove.

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Relatório apresentado com base no período de estágio obrigatório realizado na Creche Nossa Senhora de Lurdes, como pré-requisito da disciplina de Estágio Supervisionado em Educação Infantil II, orientado pela professora Vanda Cristina Moro Minini, realizado pelas alunas Arline da Silveira e Carolina de Oliveira, acadêmicas da oitava fase do curso de Pedagogia da Universidade Federal de Santa Catarina. FLORIANÓPOLIS, JULHO DE 2010. "A criança é feita de cem. A criança tem cem mãos, cem pensamentos, cem modos de pensar, de jogar e de falar. Cem, sempre cem modos de escutar as maravilhas de amar. Cem alegrias para cantar e compreender. Cem mundos para descobrir. Cem mundos para inventar. Cem mundos para sonhar. A criança tem cem linguagens (e depois, cem, cem, cem), mas roubaram-lhe noventa e nove. A escola e a cultura separam-lhe a cabeça do corpo. Dizem-lhe: de pensar sem as mãos, de fazer sem a cabeça, de escutar e de não falar, de compreender sem alegrias, de amar e maravilhar-se só na Páscoa e no Natal. Dizem-lhe: de descobrir o mundo que já existe e de cem, roubaram-lhe noventa e nove. Dizem-lhe: que o jogo e o trabalho, a realidade e a fantasia, a ciência e a imaginação, o céu e a terra, a razão e o sonho, são coisas que não estão juntas. Dizem-lhe: que as cem não existem. A criança diz: ao contrário, as cem existem."

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