Radiation Pulses
Mostrando 1-12 de 27 artigos, teses e dissertações.
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1. Transistor Avalanche Non-Coherent Pulse Generator
Abstract A transistor avalanche noise generator (TANG) is described. It is based on an off-the-shelf RF transistor with an integrated planar monopole. From a 70 V DC power it generates sub-nanosecond pulses with amplitudes close to 1 V. The proposed solution does not employ step recovery diodes, and it is based as the name implies on the operation of a bipol
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-06
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2. Recovery of chitin and chitosan from shrimp waste with microwave technique and versatile application
RESUMO: Neste estudo, a quitina e a quitosana foram extraídas de resíduos de Litopenaeus vannamei utilizando métodos químicos e do micro-ondas. Os resíduos de camarão foram limpos, secos e peneirados a 16, 32 e 60 mesh, e as amostras foram despigmentadas, desmineralizadas e desproteinizadas. Posteriormente, a quitina foi submetida a processo de desacet
Arq. Inst. Biol.. Publicado em: 28/10/2019
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3. Obtaining an Optical Trap Type Surface by Plasma Electrolytic Oxidation
High performance solar collectors are those with high selectivity surfaces, high solar radiation absorption and that do not thermally reemit to the external environment. Strategies to enhance this performance might involve surface porosity modification. In this work, a plasma treatment technique called plasma electrolytic oxidation (PEO) has been tested to p
Mat. Res.. Publicado em: 01/03/2018
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4. LPS levels in root canals after the use of ozone gas and high frequency electrical pulses
Abstract The present study aims to verify the effect of ozone gas (OZY® System) and high frequency electric pulse (Endox® System) systems on human root canals previously contaminated with Escherichia colilipopolysaccharide (LPS). Fifty single-rooted teeth had their dental crowns removed and root lengths standardized to 16 mm. The root canals were prepared
Braz. oral res.. Publicado em: 15/03/2016
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5. Modificaciones físicas, químicas y enzimáticas y sus efectos sobre las propiedades de las películas de quitosano
Recent research on biopolymer has focused its efforts to provide technological solutions to current and future challenges in the field of science and technology of materials. The properties of chitosan films have been modified by enzymatic and physical treatments such as the application of radiation, electric pulses, plasma, heat treatments, use of supercrit
Matéria (Rio J.). Publicado em: 2014-09
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6. Estudo teórico da estrutura eletrônica e da dinâmica induzida por lasers da molécula de HCl
Potential energy and dipole moment curves for the HCl molecule were computed. Calculations were performed at different levels of theory (DFT, MRCI). Spectroscopic properties are reported and compared with experimental data, for validating the theoretical approaches. Interaction of infrared radiation with HCl is simulated using the wave packet formalism. The
Quím. Nova. Publicado em: 2013
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7. Modelagem e caracterização da propagação de pulsos transientes causados por radiação ionizante / Modeling and characterization of the propagation of transient pulses caused by ionizing radiation
A propagação de eventos transientes na lógica combinacional é estudada através da simulação elétrica do circuito, utilizando-se o simulador Hspice. Uma das fontes de falhas transientes é o pulso transiente causado por partículas ionizantes que atingem o circuito. O estudo é centrado nas propriedades de mascaramento elétrico das portas lógicas. E
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 2010
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8. Projeto e construção de um amplificador paramétrico óptico operando no infravermelho médio / Design and construction of an optical parametric amplifier operating in the mid-infrared
Um Amplificador Paramétrico Óptico (optical parametric amplifier - OPA) é uma fonte de luz coerente, de alta qualidade e sintonizável, baseada em processos ópticos não-lineares de segunda ordem. Alguns modelos possuem largura de banda estreita e um amplo intervalo de sintonia, podendo alcançar regiões que vão desde o ultravioleta até o infravermelh
Publicado em: 2010
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9. Waves in nuclear matter / Ondas na matéria nuclear
Assuming that nuclear matter can be treated as a perfect fluid, we study the propagation of perturbations in the baryon density. The equation of state is derived from a relativistic mean field model, which is a variant of the non-linear Walecka model. The expansion of the Euler and continuity equations of relativistic hydrodynamics around equilibrium configu
Publicado em: 2009
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10. Experimental development and mathematical simulation of the photochemically initiated methyl methacrylate pre-polymerization process. / Desenvolvimento experimental e simulação matemática do processo de pré-polimerização fotoiniciada do metacrilato de metila (MMA).
The aim of this work is the experimental optimization, the mathematical modeling and the simulation of the photochemically initiated pre-polymerization process of methyl methacrylate (MMA). According to the industrial interests a pre-polymer of narrow molecular weight distribution (MWD) and defined weight concentration was pointed as an optimum since it impr
Publicado em: 2006
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11. Sistema multicanal de geração e recepção de ondas ultra-sonicas para transdutor matricial linear / Multichannel system for generation and detection of ultrasonic waves with a linear array transducer
Ultrasound in medicine has gone through great evolution in the last few decades and has occupied important position as a tool for therapy and diagnosis. This is due to the ultrasound equipment be of relatively low-cost, ultrasound is a non-ionizing radiation, is a non-invasive imaging method, and the images are created and seen in real time. It is common the
Publicado em: 2006
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12. Dependence of transition probabilities for non-linear photo-ionization of He atoms on the structure of the exciting radiation pulses
We discuss the expected dependence of the probability transitions for 2-photon and 3-photon absorption in Helium gas on the spatial and temporal structure of the exciting radiation pulses. Regarding spatial structure, we assumed a Gaussian radial intensity distribution; we find, as expected, that the 2-photon and 3-photon processes become negligible at dista
Brazilian Journal of Physics. Publicado em: 2005-09