74 resultados para PERSISTENT LUMINESCENCE
em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"
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Persistent photoconductivity (PPC) in vanadyl phthalocyanine (VOPc) organic light-emitting diodes was investigated using photoconductive time response, photocurrent-voltage characteristics and charge extraction in linearly increasing voltage (CELIV) measurements. The experiments were performed in phase 1 (amorphous) and in phase 2 (crystalline) samples obtained by the physical vapour deposition (PVD) technique over ITO/glass electrodes with an Al covering electrode. The results indicated a photoconductivity with a long decay time in phase 1 VOPc described by a stretched exponential relaxation. The device showed a rectifying behaviour and the mobility of holes was measured by CELIV, following a dispersive model. In crystalline samples the PPC effect was not observed and the dominant mechanism of transport of holes was hopping in a Gaussian density of states.
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Background: Persistent air leak after pulmonary resection is a difficult complication for thoracic surgeons to manage. Objectives: To show the results of our experience treating persistent pleuropulmonary air leak with autologous blood and review the literature on this specific method of treatment. Methods: Retrospective study of patients with persistent aerial pleuropulmonary fistula treated with autologous blood. The patient's own blood was collected from a peripheral vein and directly introduced through the pleural drain. An inverted siphon was located in the drainage system to avoid prolonged clamping of the drain. This siphon impeded blood return but not air escape. Results: Between January 2001 and August 2008, 27 patients were treated by the above method. Patient age ranged from 2 to 74 years, and 78% were male. Each procedure used a mean quantity of 92 ml blood. Mean persistent air leak time before pleurodesis was 10.6 days and mean time to fistula resolution after pleurodesis was 1.5 days. Twenty-three (85%) patients had persistent pleuropulmonary air leak closed with the above procedure. Conclusion: Treating persistent pleuropulmonary air leak with autologous blood is promising, but further studies are required to quantify its real effectiveness. Copyright (C) 2009 S. Karger AG, Basel
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Background: Acral persistent papular mucinosis is a rare localized form of lichen myxedematosus with few case reports and no documented therapeutic options.Objective: To report full resolution of acral persistent papular mucinosis after electrocoagulation.Methods: Case report of a 51-year-old white female diagnosed with an acral persistent papular mucinosis. The clinical and histopathologic features, treatment provided, and response to treatment are detailed.Results: Acral persistent papular mucinosis presented as multiple asymptomatic normochromic papules on the wrists. Treatment with topical and intralesional steroids was unsatisfactory. Gentle electrocoagulation led to complete resolution of the lesions and negligible scarring. The favorable results remained for 6 months of follow-up, and no new lesions have emerged.Conclusion: Our case of acral persistent papular mucinosis was successfully treated with electrocoagulation and long-lasting, excellent cosmetic results.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Radioluminescence (RL) emissions were obtained for the BaZrO3 self-assembled nanocrystals under decaoctahedral shape, if produced via microwave-assisted hydrothermal method. Trapped F centers created within the band gap are the result of order-disorder effects, which act as key factors supporting significant RL emission through a detrapping process. The influences of size and morphology on RL properties are take into account. No radiation damage or loss of emission intensity was observed. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Blue luminescence emission around 480 nm through cooperative upconversion from pairs of Yb3+ ions implanted into 60TeO(2)-10GeO(2)-10K(2)O-10Li(2)O-10Nb(2)O(5) tellurite glasses and excited by a cw laser at 1.064 mum is demonstrated. Cooperative luminescence emission enhancement owing to the temperature dependent multiphonon-assisted anti-Stokes excitation process of the ytterbium ions is also observed. The experimental results revealed a fourfold enhancement in the cooperative luminescence emission when the sample was heated in the temperature range of 20 degreesC-260 degreesC. The thermally induced enhancement is assigned to the effective absorption cross-section for the ytterbium ions which is an increasing function of the medium temperature. (C) 2002 American Institute of Physics.