969 resultados para Fluoroindate glasses


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The increasing demand for devices for solid state applications in many technological areas has resulted in a high demand for new materials. Among these material have the advantage of being manufactured with different chemical compositions, and may have physical properties equal to or higher than the corresponding crystalline material. The aim of this paper was to produce borate glass system 50B2O3 – 15CuO – 20Li2O – 15X (X = Na2O, K2O, RbCl e Cs2O) to analyze the influence of the atomic radius of alkali in the physical properties of this glass system. The glasses were synthesized by the process of melting and molding. The characteristic temperatures were determined by the technique of scanning calorimetry (DSC). The non-crystalline was determined by x-ray diffraction. In order to determine the molar volume a density measurement by using the Archimedes method was used. The structural characterization was carried out using the technique of infrared spectroscopy

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New Yb3+, Er3+ and Tm3+ doped fluoro-phosphate glasses belonging to the system NaPO3–YF3–BaF2–CaF2 and containing up to 10 wt% of rare-earth ion fluorides were prepared and characterized by differential scanning calorimetry, absorption spectroscopy and up-conversion emission spectroscopy under excitation with a 975 nm laser diode. Transparent and homogeneous glass-ceramics have been reproducibly obtained with a view to manage the red, green and blue emission bands and generate white light. X-ray diffraction as well as electron microscopy techniques have confirmed the formation of fluorite-type cubic nanocrystals at the beginning of the crystallization process while complex nanocrystalline phases are formed after a longer heat-treatment. The prepared glass-ceramics exhibit high optical transparency even after 170 h of thermal treatment. An improvement of up-conversion emission intensity – from 10 to 160 times larger – was measured in the glass-ceramics when compared to the parent glass, suggesting an important incorporation of the rare-earth ions into the crystalline phase(s). The involved mechanisms and lifetime were described in detail as a function of heat-treatment time. Finally, a large range of designable color rendering (from orange to turquoise through white) can be observed in these materials by controlling the laser excitation power and the crystallization rate.

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The photosensitivity of GeSx binary glasses in response to irradiation to femtosecond pulses at 800 nm is investigated. Samples with three different molecular compositions were irradiated under different exposure conditions. The material response to laser exposure was characterized by both refractometry and micro-Raman spectroscopy. It is shown that the relative content of sulfur in the glass matrix influences the photo-induced refractive index modification. At low sulfur content, both positive and negative index changes can be obtained while at high sulfur content, only a positive index change can be reached. These changes were correlated with variations in the Raman response of exposed glass which were interpreted in terms of structural modifications of the glass network. Under optimized exposure conditions, waveguides with positive index changes of up to 7.8x10−3 and a controllable diameter from 14 to 25 μm can be obtained. Direct inscription of low insertion losses (IL = 3.1 – 3.9 dB) waveguides is demonstrated in a sample characterized by a S/Ge ratio of 4. The current results open a pathway towards the use of Ge-S binary glasses for the fabrication of integrated mid-infrared photonic components.

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This work was based on a case study of improvement of the warehouse layout of a multinational automotive glass sector, located in the State of Sao Paulo. The aim was to propose a layout template to be more effective and besides optimizing production would also promote an increase in warehouse packaging capacity for metal containers containing glasses, thus reducing operating costs. To achieve the desired purpose, it was developed two layout proposals and to this end inventory management tools have been used, such as ABC curve and the Spaghetti Diagram, and other concepts of Packaging Engineering and Logistics. By the end of this work, it was obtained as a result, a project in which it was possible to rearrange the packages according the demand, and the developed changes became the most efficient layout both in storage capacity as well as in the internal drive

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One of the areas of human identification is Cheiloscopy, the name given to the study of the lips, their characteristics (such as thickness, position of the grooves and grooves) and the record of the impressions left by them. There are variations in the layout of the lines and fissures of the lips, which are unique to each individual, permanent and unchanging. The lip print rarely changes, enduring minor traumas such as inflammation or sores. In criminal investigations, lip prints, visible through the presence of lipstick, can be found on glasses, napkins, clothes, cigarettes, indicating a relationship between the subject and the scene of the crime. Latent impressions may be revealed employing specific chemicals such as powder of silver and aluminum nitrate. Although it is not a very common method, Cheiloscopy may become very useful in forensics due to the extensive amount of valuable information that it brings. The objective of this study was to review the literature on the use of Cheiloscopy in human identification, using traditional and digital methods. It was found that the literature is still in need of studies in this area. The advent of new digital technologies can facilitate the implementation of technical expertise, generating speed and objectivity. New research studies are necessary, especially in the development of digital methods. The application of Cheiloscopy can greatlyhelp with Law, in the identification of living suspects and dead individuals. In the end the benefit will fall to society as a whole.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The sol-gel process is a technique based on the hydrolysis and polycondensation of metal alkoxides have been investigated as an alternative for the preparation of vitreous or glassceramic materials, for allowing the obtaining of high-purity materials at low temperatures, and to obtain hybrid materials with different compositions. When ORMOSILs are doped with nanoparticles, are called nanocomposites, and its functionality arises when electrons confined in scale three-dimensional structures near zero are excited. In principle, such materials exhibit discrete energy level, with peaks in the absorption spectrum. Therefore, the glasses doped semiconductor nanocrystals are important candidates for the preparation of optical filters with sharp cut-off, and are being exploited commercially for coloring glasses. This study evaluates the optical properties presented by hybrid films of silica doped with copper nanoparticles. The matrix was prepared using the alkoxides 3-glycidoxypropyltrimethoxysilane (GPTS) and tetraethylorthosilicate (TEOS) doped with Cu2O and hydrolyzed under reflux conditions in two different acidic conditions (HCl and HBr). After thermal treatment at temperatures between 100 °C and 170 °C and/or under the action of commercial black light radiation, CuCl and CuBr present in the hybrid film are transformed into nanoparticles of CuCl or CuBr. The UV-VIS absorption identified the absorption bands, and its variation

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Each year individuals have sought a better quality of life and work, in this case, the science of Bio-insurance needs to keep up with technological advances and the needs of society to minimize or eliminate the risks of accidents. This study evaluated the most common accidents involving health staff from 2007 to 2011 in Araçatuba-SP. 478 accidents were recorded, and 78.7% with percutaneous involvement, 9% with intact skin, 4% with no skin intact, with 7.3 mucous and 1.05% other types of exposures. Most accidents were caused by needles with lumen (68.0%), followed by other agents (14.1%), accidents with blades (8.5%) or needles without lumen (5.5%); 3.7% did not answer and 0.2% were accidents with glasses. When checking the condition in which the accident occurred, 26.0% did not specify, 25.1% occurred in the disposal and / or handling sharp objects, 12.0% at the time of drug administration, 6.9% puncture, 3.7% occurred during recapping the needle. These data show that the most common accidents are those involving needles with lumen and / or sharp objects and due to these factors, the industry of health materials have sought alternatives to minimize such accidents as needles with protective, vacuum collection . Thus, it appears that reporting accidents is important for the development of technical and / or safer materials for patients and health workers.

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Moderate wine intake (i.e., 1-2 glasses of wine a day) is associated with a reduced risk of morbidity and mortality from cardiovascular disease. The aim of this study was to evaluate the anti-atherosclerotic effects of a nonalcoholic ethyl acetate fraction (EAF) from a South Brazilian red wine obtained from Vitis labrusca grapes. Experiments were carried out on low-density lipoprotein (LDL) receptor knockout (LDLr-/-) mice, which were subjected to a hypercholesterolemic diet and treated with doses of EAF (3, 10, and 30 mg/kg) for 12 weeks. At the end of the treatment, the level of plasma lipids, the vascular reactivity, and the atherosclerotic lesions were evaluated. Our results demonstrated that the treatment with EAF at 3 mg/kg significantly decreased total cholesterol, triglycerides, and LDL plus very low-density lipoprotein levels compared with control hypercholesterolemic mice. The treatment of mice with EAF at 3 mg/kg also preserved the vasodilatation induced by acetylcholine on isolated thoracic aorta from hypercholesterolemic LDLr-/- mice. This result is in agreement with the degree of lipid deposit on arteries. Taken together, the results show for the first time that the lowest concentration of an EAF obtained from a red wine produced in southern Brazil significantly reduced the progression of atherosclerosis in mice.

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This paper reports on Y2O3:Eu3+ containing 1 mol% of Ag-0 nanoparticle films recovered with a SiO2 layer by using glass foil as a substrate for a possible optical display device application. The obtained film showed an intense emission at 612 nm due to the Eu3+ 5D0 -> F-7(2) hypersensitive transition, a high transmittance in that emission range, an excellent optical quality, and a high absorption only below 300 nm. Moreover, despite the presence of the SiO2 layer used to improve the phosphor adhesion on Corning (R) foil substrates, the intensity ratios between the emissions assigned to Eu3+ D-5(0) -> F-7(2) (dipole electric transition) and D-5(0) -> F-7(1) (dipole magnetic transition) were not affected by it. The x and y coordinate values found in the 1931 Commission Internationale de l'Eclairage Chromaticity Diagram for this film reveal that it has a suitable pure red color emission for optical displays devices. (C) 2012 Elsevier B. V. All rights reserved.

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In this paper, we report on luminescence and absorbance effects of Er+3:Au-doped tellurite glasses synthesized by a melting-quenching and heat treatment technique. After annealing times of 2.5, 5.0, 7.5, and 10.0 h, at 300 A degrees C, the gold nanoparticles (GNP) effects on the Er+3 are verified from luminescence spectra and the corresponding levels lifetime. The localized surface plasmon resonance around 800 nm produced a maximum fluorescence enhancement for the band ranging from 800 to 840 nm, corresponding to the transitions H-4(11/2) -> aEuro parts per thousand I-4(13/2) (805 nm) and S-4(3/2) -> aEuro parts per thousand I-4(13/2) (840 nm), with annealing time till 7.5 h. The measured lifetime of the levels H-4(11/2) and S-4(3/2) confirmed the lifetime reduction due to the energy transfer from the GNP to Er+3, causing an enhanced photon emission rate in these levels.

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Sarmento C. A. P., Ferreira A. O., Rodrigues E. A. F., Lesnau G. G., Rici R. E. G., Abreu D. K., Biasi C. & Miglino M. A. 2012. [Kidney of Minke Whale (Baleanoptera acutorostrata): Architecture and structure.] Rins de Baleia Minke (Baleanoptera acutorostrata): arquitetura e estrutura. Pesquisa Veterinaria Brasileira 32(8): 807-811. Departamento de Cirurgia, Setor de Anatomia dos Animais Domesticos e Silvestres, Universidade de Sao Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Sao Paulo, SP 05508-270, Brazil. E-mail: sarmento@usp.br Among marine mammals, whale is one of the most attention-arousing animals, especially concerning its urinary tract. This system follows the pattern of mammals with regard to its constitution, however, it differs in renal morphology and number of lobes, which, in turn, form complete reniculi, agglutinated in hundreds. This structure is supported by fibrous connective tissue, but highly capable of maintaining electrolyte balance. Six pairs of kidneys of Minke whale (Balaenoptera acutorostrata), collected in 1982, in Cabedelo, Paraiba, Brazil, in the last fishing allowed, were dissected. These kidneys were preserved in 10% formaldehyde and they presented a very large histologic layer of collagen surrounding the medullary wall. The urinary collecting duct form papillary glasses, that reach a single collecting center which discharges in the ureter. It was found that the kidney of Minke whale has a lobe characteristic, with, on average, 700 reniculi; each reniculus has anatomical and functional characteristics of a unipyramidal kidney, with an inner layer (medulla), and an outer layer (cortex), and independent irrigation, with formation of individually arcuate arteries, as observed in unipyramidal terrestrial mammals. However, the set gathering all these reniculi constitutes, in the end, a multilobular and polipyramidal kidney, contrary to the morphology of most terrestrial mammals. It was not possible to distinguish the renicular cortex structures of the Minke whale in the level of light microscopy. Through scanning electron microscopy, it was possible to visualize a cortical layer located between two fibrous capsules. This joint, in turn, consists of connective tissue, which, along with a layer of collagen and elastic fibers, separates the cortex from the medulla; the kidney glomeruli were visualized, completely taken by the glomerular vessels and arranged into several layers. One notices that the glomerular cavity is almost a virtual space into which the glomerular filtrate is drained, and it does not present a globular shape. Vascularization is increased in the medullary region. The difference between the kidneys of terrestrial and marine mammals consists in the arrangement of morphological components, favoring the organ's physiology.

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We review recent progress in the mathematical theory of quantum disordered systems: the Anderson transition, including some joint work with Marchetti, the (quantum and classical) Edwards-Anderson (EA) spin-glass model and return to equilibrium for a class of spin-glass models, which includes the EA model initially in a very large transverse magnetic field. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4770066]