Leave a comment

from Magsino AutoMap, a product of CASOS at Carnegie Mellon University, assim como as simulacoes do campo eletrico, desenvolvimento, montagem e . Get JDI ELÉTRICA AUTOMAÇÃO’s email address, d****[email protected] [email protected] Rodrigo A. Ramos. † [email protected] state feedback linearization, SBA Controle e Automao. 20(4): – Silva, S. and Junior.

Author: Sazahn Dokora
Country: Burundi
Language: English (Spanish)
Genre: Marketing
Published (Last): 20 February 2013
Pages: 75
PDF File Size: 9.94 Mb
ePub File Size: 8.86 Mb
ISBN: 877-9-82882-671-6
Downloads: 76001
Price: Free* [*Free Regsitration Required]
Uploader: Dumi

Esta tese apresenta os resultados de uma investigacao eletrida em filmes epitaxiais emissores de luz baseados em InxGa1-xN. O InxGa1-xN e uma liga semicondutora ternaria do grupo III-N muito utilizada como camada activa numa gama de dispositivos optoelectronicos em desenvolvimento, incluindo diodos emissores de luz LEDs e diodos laser LDspara operacao na regiao do visivel e ultravioleta do espectro electromagnetico.

O objectivo central do trabalho prende-se com a compreensao mais profunda dos processos fisicos que estao por tras das suas propriedades opticas, preenchendo o fosso existente entre aplicacoes tecnologicas e o conhecimento cientifico. Nomeadamente, a tese aborda os problemas da medicao da fraccao de InN x eetrica multicamadas ultrafinas automzo a tensoes, a influencia da composicao e das tensoes microscopicas nas propriedades opticas e estruturais.


A metodologia seguida assenta na integracao de resultados obtidos por tecnicas complementares atraves de uma analise sistematica e multidisciplinar. Esta abordagem passa pela combinacao de: Towards this primary objective, we created the Phoenix Pilot as a crucible from which systemization of the new discipline could emerge. Using a wide range elefrica applications, Phoenix has begun building both theoretical foundations and capability for: The polycrystalline eoetrica of undoped and doped CaSO 4 are prepared by the melting method.

The formation of CaSO 4 compound is confirmed by X-ray diffraction and Fourier transform infrared studies. Scanning electron microscopic studies of CaSO 4 are also carried out. The TL-dose dependence of all three samples was studied and was observed to be almost linear in the studied range of irradiation time. The trap parameters, namely order of kinetics bactivation energy E and frequency factor s associated with the most intensive glow peaks of CaSO 4: Cu and CaSO 4 phosphors were determined using the glow curve shape Chen’s method.

Eu as an OSL phosphor. Eu phosphor and study on its thermal behavior as a function of temperature under a series of luminescence experiments. The suitability of its usage as an optically stimulated luminescence OSL dosimeter was also checked.

Eu was synthesized using the precipitation method and prepared in pellet form. The dopant concentration value was performed as 0.

caso analises estruturais: Topics by

The synthesized CaSO 4: Eu was analyzed by X-ray diffraction XRD method to confirm the product. To have an idea about the crystallography and eletricaa morphology of the material, scanning electron microscope SEM analysis were carried out. The excitation spectrum of CaSO 4: Eu showed different peaks in the region atomao with the highest one at nm.

Eu pellets were obtained and compared with the TL signals obtained after OSL measurements of the same pellets by blue light stimulation. The dosimetric properties such as dose response, minimum detectable dose, energy response, reusability, fading properties, thermal stability and effect of reading temperatures on OSL signals were examined. Eu OSL dosimeter in accordance with the presented study allows a high.

Recombination luminescence of CaSO 4: A comparative study of the excitation of luminescence by VUV radiation as well as of thermally and photostimulated luminescence has been carried out for CaSO 4: The binary system K2SO4 CaSO 4 was studied by means of heating-cooling curves, differential thermal analysis, high-temperature quenching technique and by means of a heating stage mounted on an X-ray diffractometer.


Compositions and quench products were identified optically and by X-ray. There is a eutectic at ?? C and 34 wt. Calcium langbeinite melts incongruently at ??

The melting-point of CaSO 4 ??

JDI ELÉTRICA AUTOMAÇÃO Email & Phone# | Proprietário @ JDI ELETRICA – ContactOut

C was determined by the quenching technique using sealed platinum tubes. The only intermediate crystalline phase found in the system is K2SO4??

Melting and subsolidus relations in the system K2SO4MgSO4 CaSO 4 were studied using heating-cooling curves, differential thermal analysis, optics, X-ray diffraction at room and high temperatures and by quenching techniques. This problem was partly overcome by a novel sealed-tube elstrica method, by hydrothermal synthesis, and by long-time heating in the solidus.

As a result of this study, we found: C with a field extending into the ternary system; 2 a high temperature form of MgSO4 with a sluggishly reversible inversion. An X-ray diffraction pattern for this polymorphic form is given; 3 the inversion of?? C, in agreement with grahmann; 1 4 the melting point of MgSO4 is ?? C and that of CaSO 4 is ??

C using sealed tube methods to prevent decomposition of the sulphates ; 5 calcium langbeinite K2SO4?? This resolved discrepancies in the results of previous investigators; 6 a continuous solid solution series between congruently melting K2SOP4??

The CaSO 4 field extends over a large portion of the system. Previously reported fields for the compounds K2SO4?? CaSO 4 were not found; 8 a minimum in the ternary system at: Hiperplasia angiolinfoide com eosinofilia: Feasibility study of CaSO 4: Tb,Yb as a thermoluminescent dosimeter. Tb,Ybwas developed for employment as a thermoluminescent TL dosimeter. The crystals used in this work were grown using a production route based on the Yamashita method Yamashita et al.

TL analyses have been performed and characteristics such as sensitivity, reproducibility, linearity, and fading have been studied. The highest intensity was shown for CaSO 4: Tb,Yb with a concentration of 0.

In all the samples the TL response was proportional to the absorbed dose. Therefore, the CaSO 4: Tb,Yb has potential to be used as eetrica thermoluminescent dosimeter. Impulsive eletrixa of mechanoluminescence in eletruca CaSO 4: Eu phosphor have been auromao.

ML was excited impulsively by dropping a load onto the sample. Three distinct peaks have been observed in the ML intensity versus time curve. The ML intensity increases with the increasing concentration of the dopant.

The effect of temperature on the shape and peak of Zutomao intensity was also recorded. Growth, saturation and broadening in fletrica ML peak were observed. TL glow curves of CaSO 4: Eu phosphors at different concentrations contain two TL peaks: Experimental results suggest that the ML excitation is related to the movement of dislocation with defect centres, the increase in ML with temperature autoamo due to the enhancement in dislocation capture probability, and the reduction is due to the thermal bleaching of defect centres.

An alternative method for immediate dose estimation using CaSO 4: Dy based TLD badges. Dy based Thermoluminescence dosimeters TLDs are being used in country wide personnel monitoring program in India. As the dosimetric procedure involves total integrated counts for dose conversion, the dosimeters are typically read about a week after receiving.

However in the event of a suspected over exposure, where urgent processing is expected, this poses limitation.


Post irradiation annealing treatment is used in such cases of immediate readout of cards. In this paper we report a new and easier to use technique based on optical bleaching for the urgent processing of TLD cards. This method can be used for immediate dose estimation using CaSO 4: On the basis of the differential solubilities of gypsum and anhydrite, a method was developed to remove calcium from the scheelite leaching solution by adding anhydrite as an inoculating crystal.

The atuomao of the reaction time, concentration of the CaSO 4 inoculating crystals, and temperature were investigated. Calcium Sulfate CaSO 4 deposit reduces heat exchange in heat transfer equipment which adversely affects the equipment performance and plant production. In addition, the Scanning Electron Microscopic was autimao to examine the morphology and distribution of Calcium Sulfate CaSO 4 crystals deposited on titanium metal surfaces.

Based on the experimental results, Calcium Sulfate Epetrica 4 scale obtained in the present study was almost constant on coated carbon steel in which the rate of scale deposition is equal to the rate of scale removal. However, the deposition of Calcium Sulfate CaSO 4 observed on titanium material was increased as the speed increased.

Average particle size is found to be in the range nm with Hexagonal morphology and PL studies showed emission peaks at nm, when samples were excited by nm. However under identical condition it is observed that intensity of emission get enhanced for 0. A phosphor with narrow emission band around nm is desirable, since at this wavelength the transmission of standard glass, polarizing plastic, other coating and LCD material is at acceptable level.

Numerical simulation of calcium sulfate CaSO 4 fouling in the plate heat exchanger. Plate heat exchanger is a widely used apparatus in the industrial production processes. Through a numerical simulation method, this paper calculates the deposition rate of CaSO 4 fouling on heat transfer surfaces of the plate heat exchanger under saturation in the bulk. The effects of CaSO 4 concentration in the range 0.

The simulation results are compared with the experimental results showing similar trend. The simulation results show that the concentration and the flow velocity affect significantly the fouling characteristics in the plate heat exchanger.

The deposition mass rate, removal mass rate, and asymptotic value of fouling resistance all increase with the increase in CaSO 4 concentration and the inlet temperature of the hot fluid, while the asymptotic value of fouling resistance decreases with the increasing of inlet flow velocity. The influence of the inlet temperature of cold fluid may be negligible. A new and highly sensitive thermoluminescence phosphor for versatile dosimetry. With the advent of newer techniques for dose reduction coupled with the development of more sensitive detectors, the radiation doses in radiological medical investigation are decreasing.

Nevertheless, keeping the tenet in mind that all radiation doses could entail risk, there is a need to develop more sensitive dosimeters capable of measuring low doses. This paper gives the account of the development of a new and sensitive phosphor CaSO 4: