Advances and Developments in Strategies to Improve Strains of Saccharomyces cerevisiae and Processes to Obtain the Lignocellulosic Ethanol-A Review

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

Cinética de dissolução da superfície de aço SAE-AISI 1005 em meio ácido

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

Rugged, Portable Tungsten Coil Atomic Emission Spectrometer

Tungsten coil atomic emission spectrometry is an ideal technique for field applications because of its simplicity, low cost, low power requirement, and independence from cooling systems. A new, portable, compact design is reported here. The tungsten coil is extracted from an inexpensive 24 V, 250 W commercial light bulb. The coil is housed in a small, aluminum cell. The emission signal exits from a small aperture in the cell, while the bulk of the blackbody emission from the tungsten coil is blocked. The resulting spectra exhibit extremely low background signals. The atomization cell, a single lens, and a hand-held charge coupled device (CCD) spectrometer are fixed on a 1 x 6 x 30 cm ceramic base. The resulting system is robust and easily transported. A programmable, miniature 400 W solid-state constant current power supply controls the temperature of the coil. Fifteen elements are determined with the system (Ba, Cs, Li, Rb, Cr, Sr, Eu, Yb, Mn, Fe, Cu, Mg, V, Al, and Ga). The precision ranges from 4.3% to 8.4% relative standard deviation for repetitive measurements of the same solution. Detection limits are in the 0.04 to 1500 mu g/L range. Accuracy is tested using standard reference materials for polluted water, peach leaves, and tomato leaves. For those elements present above the detection limit, recoveries range from 72% to 147%.

Síntese e processamento de cerâmicas em forno de microondas doméstico

O uso de microondas no processamento e obtenção de materiais tem adquirido nos últimos anos crescente interesse por parte de diversas áreas do conhecimento como a química e a engenharia de materiais. Neste sentido, aparatos especialmente projetados têm começado a ser descritos na literatura como reatores e câmaras de processamento a microondas visando aplicação na pesquisa e na indústria. em particular o uso de fornos de microondas domésticos em atividades científicas tem se mostrado de interesse dado uma série de novas aplicações, simplicidade e baixo custo. O presente trabalho reporta um dispositivo desenvolvido a partir de um forno de microondas doméstico, capaz de efetuar sínteses e processamentos de sólidos mesmo quando os materiais envolvidos não possuem susceptibilidade as microondas. O novo dispositivo tem sido utilizado com sucesso na síntese de óxidos metálicos e, em especial na sinterização e ordenamento de redes cristalinas de filmes finos.

Avaliação da resistência à corrosão do aço AISI 420 depositado por processos variados de aspersão térmica

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Pineapple Leaf Fibers for Composites and Cellulose

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

In2O3 microcrystals obtained from rapid calcination in domestic microwave oven

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

Metallurgical evaluation of a copper-based alloy for dental castings.

The present study was designed to evaluate the metallurgical properties of an experimental, low-cost copper-zinc-aluminum-nickel alloy for dental castings. Some specimens were subjected to heat treatment after induction casting. The extent of corrosion was determined by measuring weight loss of specimens stored in a sodium sulfite solution. In the as-cast specimens, tests demonstrated the presence of three phases: the first consisted of copper-zinc-aluminum, the second was similar but lower in copper and aluminum, and the third consisted of an intermetallic compound of manganese-nickel-phosphorus. After heat treatment, the first phase remained relatively constant, the second was converted to Cu3Al, and the third increased in volume. The weight loss from the as-cast specimens was eight times that of the heat-treated specimens. It was concluded that the heat treatment substantially changed the microstructure and improved the corrosion resistance of the experimental alloy.

Polissacarídeos biodegradáveis úteis para a preparação de sistemas de liberação controlada de fármacos. Parte 1: Quitosana

Due to an increasing interest, a vast number of biodegradable polymers have been obtained recently. Polymers naturally produced, such as cellulose, starch, chitosan and alginate, represent biodegradable materials, with low toxicity and low cost. Among polysaccharides, chitosan has been of great interest of the industrial and academic research, due to its special qualities of biodegradability and biocompatibility and, on the other hand, to the versatility of its use in several physical forms and products. A significant growth in the development of new dosage forms capable to deliver the drug in a controlled and targeted way has been observed in these last years. Such pharmaceutical forms search, mainly, the reduction of the dose administered and of the administration frequency, the reduction of adverse side effects and, consequently, a better patient compliance. The present paper describes the use of chitosan in pharmaceutical products, especially in drug controlled delivery systems.

Desenvolvimento de um dispositivo para obtenção de monocristais de ligas à base de cobre

This paper describes the drawing, construction and optimization of a device, which can be used to obtain single crystals of different metallic materials with melting point from 550 to 1050°C. Components of ease obtaining and of low cost were used. The device was based on the modified Bridgman technique and it was used to obtain single crystals of copper-based alloys. The temperature axial profiles and a difference less then 1% in the temperature between the wall and the center of the ceramic tube in the critical region for obtaining single crystals of good quality indicated that the oven presents a good thermal stability. Single crystals of CuZnAl and CuAlAg alloys of good quality were growth and characterized using optical microscopy and Laüe X-ray back reflection.

Ceramic Crucible Corrosion by Heavy Metal Oxide Glasses, Part II: Diffusion Study

Due to their low cost and high resistance to corrosion, ceramic crucibles can be used for the melting of PBG glasses (PbO-BiO 1.5GaO 1.5). These glasses present good window transmission from ultra-violet to infrared, making their use as optical fibres promising. However, their disadvantage is the high reactivity, leading to the corrosion of different crucibles, including gold and platinum ones. In this work, the corrosion of Al 2O 3, SnO 2 and ZrO 2 crucibles after melting at temperatures varying from 850 to 1000°C, was evaluated by Scanning Electronic Microscopy (SEM) in conjunction with microanalysis by EDS. The lead diffusion profile in the crucible material was obtained. Diffusion coefficients were calculated according to the Fick and Fisher theories. Results indicated that the different crucibles presented similar behaviour: in the region near the interface, diffusion occurs in the volumetric way and in regions away from the interface, diffusion occurs through grain boundary.

Influência da geometria do martelo na determinação da força durante o ensaio de impacto Charpy-V

The instrumentation applied to the Charpy test machine allows the accompaniment of the specimen answer front the impact load, in form of a sign characteristically dynamic representative of the deformation process and it fractures of material tested. The main advantages of the rehearsal conventional Charpy: low cost, manufacturing sample facilities and simple handle the machine. With the instrumentation, the number of information regarding the process of fracture of the specimen increases. In this work discusses the influence of the hammer geometry in determination of the force during the process of specimen fracture submitted to the instrumented impact test Charpy-V. The purpose is obtaining a hammer, in conformity with Norma ISO 14.556, with great sensibility to register the force during the impact. Two geometries different from hammers were instrumented and rehearsed with material of low tenacity, in this case the steel ABNT 4140 in the condition of having normalized. It could be proven as larger the sensibility of the hammer, adult will be the effects of the shock waves in the strain gages of the transducer.

Avaliação de desempenho do microaspersor amanco em bancada de testes

The need for a rational use of water and supply of food for a growing world population have led to the development of research in the area of irrigation systems. Thus, some irrigation systems which join efficiency with low cost of material have been developed. Although some technical characteristics are provided by the manufacturers, tests are required to verify functioning of the system and uniformity of water distribution. Continuous research on uniformity, characteristics of the materials and design of water distribution systems is essential for system improvement. Therefore, the objective of this work was to evaluate the CV (manufacturer's coefficient of variation) of Amanco microsprinkler (1.0 mm light green nipple) using bench testing in the laboratory of Irrigation at UNESP - FCA campus of Botucatu-SP. Twenty-five microsprinklers in a sequential design were used in the tests. Three flow systems were tested as follows: a Coil system based on serial connected pipes; a Lateral system, the most common system in which secondary lines are fed by a main line; and a Mesh system used in the urban water supply. The results showed that 4.17% CVf met the production standards and the Lateral and Mesh systems were similar regarding outflow using bench testing. The Mesh system presented the highest mean value of outflow and the lowest range of variation.

Developed and studies on technical and economical viability of an environmental efficient urinal

This work introduces an innovative urinal for public convenience, that promotes at the same time water reuse and personal higiene, in a safe and economical way . Furthermore it demonstrates the latest technology and its technical and economical viabillity of utilization in new and already existing buildings facilities. This new model of personal higiene equipment offers as main benefits the improved economy with subsequent decrease in drinkable water consumption, sanitary safety, low cost and easy installation due to its simplicity and to the fact that it can be installed in already existing facilities. The proposal is constituted by a higienic, ecological and smart system for flushing of public urinals. It is a conjugated system of lavatory and urinal that reuses hands higienization water from the lavatory for flushing purpose. The proposed urinal can be operated manually or automatically by means of a presential sensor. The system promotes drinkable water economy by a rational utilization by avoiding the use of waste water from hand washing in place of clean water for flushing. The proposed equipment increases the economy of clean water in a simple and economical way and it can be installed in any type of public lavatory facilitie such as schools, public buildings, hospitals, commercial buildings, bus terminals, airports, stadiums, parking buildings and shopping centers. Additional benefits of the proposed system is the suggestion of hands washing before and after the use of the urinal without contamination risks from focet handling.and render more attractive the installation for a rational use of clean water in commercial and industrial buildings. Pay-back has shown to be very attractive for a number of internal return rates and also very attractive from the point of view of environmental protection.

High-yield direct synthesis of Mg 2FeH 6 from the elements by reactive milling

Magnesium complex hydrides as Mg 2FeH 6 are interesting phases for hydrogen storage in the solid state, mainly due to its high gravimetric and volumetric densities of H2. However, the synthesis of this hydride is not trivial because the intermetallic phase Mg2Fe does not exist and Mg and Fe are virtually immiscible under equilibrium conditions. In this study, we have systematically studied the influence of the most important processing parameters in reactive milling under hydrogen (RM) for Mg 2FeH 6 synthesis: milling time, ball-to-powder weight ratio (BPR), hydrogen pressure and type of mill. Low cost 2Mg-Fe mixtures were used as raw materials. An important control of the Mg 2FeH 6 direct synthesis by RM was attained. In optimized combinations of the processing parameters, very high proportions of the complex hydride could be obtained. © (2011) Trans Tech Publications.