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1

Isolation and identification of flavonoid (-)-4'-methyl-epigallocatechin of roots from Maytemus obtusifolia Mart. (Celastraceae)  

International Nuclear Information System (INIS)

Portuguese ... Orig. Title Isolamento e identificacao do flavonoide (-)-4'-metil-epigalocatequina das raizes de Maytenus obtusifolia Mart. (Celastraceae)

2006-05-19

2

Intelligent techniques applied in identifying fraudsters industrial consumers of electricity; Tecnicas inteligentes aplicadas na identificacao de consumidores industriais fraudadores de energia eletrica  

Energy Technology Data Exchange (ETDEWEB)

The development of a computational intelligent tools based on neural network to identify commercial losses or fraud (theft energy), considering information from a database electric utility, is presented.

2009-07-01

7

Modelling and simulation of a solar cooler based on physical adsorption; Modelagem e simulacao de um refrigerador solar por adsorcao fisica  

Energy Technology Data Exchange (ETDEWEB)

This study describes the construction of a simple mathematical model its validation through the simulation in transient state of a real cycle performed by a solar refrigerator based on physical adsorption using an activated carbon/methanol pair. The deviation from experimental results was 4% for the cycled mass of methanol, 2.2 % for maximum collector average temperature, and 3 x 10{sup -3} for the theoretical cycle coefficient of performance. Additional simulations of the same cycle inputting values representing different types and larger amounts of activated carbon showed the possibility of increasing the cycled methanol mass up to about 150%. (author) 26 refs., 16 figs., 9 tabs.

1993-12-31

8

Dynamic modelling of check valves in shipping terminals; Modelagem dinamica de valvulas de retencao em terminais maritimos  

Energy Technology Data Exchange (ETDEWEB)

As usual a shipping terminal contains a header and its diameter is smaller than the main pipeline diameter. This diameter reduction amplifies the effects caused by hydraulic transients. It was noticed during simulations that check valves without dynamic modeling may introduce some error in the maximum pressure results without a dynamic model approach. The current paper uses commercial pipeline simulation software to model the dynamic behavior of the check valves. It was studied the header diameter influence and how the check valve model type may change the maximum pressure in the pipeline. It was proved that even a pipeline that works with low pressure and small elevation drop needs a detailed valve modeling to prevent the calculation of unreal pressure values in the region with diameter reduction. (author)

2005-07-01

9

Comparative study on tea chemical analysis; Estudo comparativo na analise quimica de chas  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the application of the instrumental analytical methods: neutron activation techniques, atomic absorption spectroscopy and flame emission spectroscopy, used to analyse some home-made teas, determining Na, K and Cl and comparing the results. This study verify whether the home-made teas used for rehydration of the children reach the composition recommended by WHO (World Health Organization). (author). 6 refs., 6 tabs.

1995-12-31

10

Analysis of the economic potential of the landfill in the municipality of Chapeco - SC, Brazil; Analise do potencial economico do aterro sanitario do municipio de Chapeco - SC  

Energy Technology Data Exchange (ETDEWEB)

This study aims to evaluate the economic and environmental viability of the exploitation of methane gas (CH4) - biogas - concentrated at the bottom of the mountains of waste from landfill Chapeco for power generation. The landfill receives approximately of 80 tons / day, the vast majority of domestic origin.

2006-07-01

11

Application of self-adaptive procedure to the thermal problems analysis under steady-state and transient regimens; Aplicacao de procedimento auto-adaptativo na analise de problemas termicos no regime permanente e transiente  

Energy Technology Data Exchange (ETDEWEB)

This work describes a procedure for the adaptive time dependent Finite Element Method using an automatic mesh refinement (H-Version) that efficiently reduces estimated errors ( a posteriori) below pre-assigned limits. Classical model problem for steady-state heat transfer are investigated, and the results are compared with the analytical solution. Then some typical time-dependent problem are qualitatively analysed. (author) 10 refs., 7 figs.

1990-12-31

12

Gastrointestinal transit after transverse colostomy: study of solid radiopaque markers progression and others clinical and radiological events - analysis of 20 cases; Transito gastrintestinal apos fechamento de transversostomia: estudo atraves da progressao de marcadores solidos radiopacos e de outros eventos clinicos e radiologicos - analise de 20 casos  

Energy Technology Data Exchange (ETDEWEB)

The gastrointestinal transit was studied in 20 patients with loop transverse colostomies and previously normal colons. This analysis was performed through radiological observation of progression of 20 radiopaque pellets and measurements of its transit time in the various segments of the digestive tract. An evaluation of other related clinical and radiological events was carried out sentimentality's. In order to better understand the influence of the surgical procedure, the study was performed under similar dietary and supportive care conditions and standard radiological studies before and after the re-establishment of transit, thus enabling a comparison with the same individual. (author)

1988-07-01

13

Application of neutron activation analysis method in leaves of Casearia obliqua medicinal plant; Aplicacao do metodo de analise por ativacao com neutrons na analise de folhas da planta medicinal Casearia obliqua  

Energy Technology Data Exchange (ETDEWEB)

The pharmacological properties of medicinal plants have been related to the presence of organic compounds, however elements are also known to have an important participation in the active compounds constitution process. In this study, instrumental neutron activation analysis (INAA) was applied to determine elements in leaves of Casearia obliqua medicinal plant collected at two different locations in the Atlantic Forest, Brazil, SP. Soil samples collected from where this plant was grown were also analyzed in order to verify if there is a correlation between the elements present in soils and plant leaves. Br, Ca, Cl, Co, Cr, Cs, Fe, K, La, Mn, Na, Rb, Sb, Sc and Zn were determined in C. obliqua leaves and the elements As, Ca, Ce, Eu, Fe, Hf, La, Lu, Nd, Rb, Sc, Sm, Tb, Th, U and Zn in soils. Soil samples collected from two different locations presented similar concentrations for most elements. Likewise, C. obliqua leaves collected from the two locations presented similar elemental ...

2005-07-01

14

Markov random fields simulation: an introduction to the stochastic modelling of petroleum reservoirs; Simulacao de campos aleatorios markovianos: uma introducao voltada a modelagem estocastica de reservatorios de petroleo  

Energy Technology Data Exchange (ETDEWEB)

Stochastic simulation has been employed in petroleum reservoir characterization as a modeling tool able to reconcile information from several different sources. It has the ability to preserve the variability of the modeled phenomena and permits transference of geological knowledge to numerical models of flux, whose predictions on reservoir constitute the main basis for reservoir management decisions. Several stochastic models have been used and/or suggested, depending on the nature of the phenomena to be described. Markov Random Fields (MRFs) appear as an alternative for the modeling of discrete variables, mainly reservoirs with mosaic architecture of facies. In this dissertation, the reader is introduced to the stochastic modeling by MRFs in a generic sense. The main aspects of the technique are reviewed. MRF Conceptual Background is described: its characterization through the Markovian property and the equivalence to Gibbs distributions. The framework for generic modeling of MRFs is ...

1998-02-01

15

Re-potentiation of hydro-generators: a proposal of analysis and implementation methodology; Repotenciacao de hidrogeradores: uma proposta de metodologia de analise e implantacao  

Energy Technology Data Exchange (ETDEWEB)

The hydro-generators suffer during its operative useful life a combination of stresses of nature thermal, electric, mechanics and environmental. With the time, they are going losing the capacity to support those stresses and the power plants suffer, more and more frequently, undesirable stops for repair services and maintenance. In function of the high costs incurred with these stopped, the operation of the power plant can be economically impracticable. That unavailability of the generation for the electric system, it results in reduction of the reliability, burdening the politics of load ruling. The re-potentiation is a proposal that seeks to extend the useful life of hydro-generators, at the same time that it try to rescue the reliability and the readiness of the plant, with larger power. The power increase is usually made possible, or for the surplus of the hydro resources in excess, or for the reduction of the losses of all the components of the energy flow. That work proposes a ...

1996-07-01

16

Analysis of medicinal plant extracts by neutron activation method; Analise de extratos de plantas medicinais pelo metodo de ativacao com neutrons  

Energy Technology Data Exchange (ETDEWEB)

This dissertation has presented the results from analysis of medicinal plant extracts using neutron activation method. Instrumental neutron activation analysis was applied to the determination of the elements Al, Br, Ca, Ce, Cl, Cr, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sb, Sc and Zn in medicinal extracts obtained from Achyrolcline satureoides DC, Casearia sylvestris, Centella asiatica, Citrus aurantium L., Solano lycocarpum, Solidago microglossa, Stryphnondedron barbatiman and Zingiber officinale R. plants. The elements Hg and Se were determined using radiochemical separation by means of retention of Se in HMD inorganic exchanger and solvent extraction of Hg by bismuth diethyl-dithiocarbamate solution. Precision and accuracy of the results have been evaluated by analysing reference materials. The therapeutic action of some elements found in plant extracts analyzed was briefly discussed 70 refs., 13 figs., 15 tabs

1995-12-31

17

Analysis and optimization of the heat transfer coefficient of a finned heat exchanger submitted to natural convection; Analise e otimizacao do coeficiente de transferencia de calor de um trocador aletado submetido a conveccao natural  

Energy Technology Data Exchange (ETDEWEB)

A heat transfer (condenser) of a domestic freezer was tested in a vertical channel in order to study the influence of the chimney effect in the optimization of the heat transfer coefficient. The variation of the opening of the channel, position and the heating power of the heat exchanger in the heat transfer coefficient was considered. The influence of the surface emissivity on the heat transfer by thermal radiation was studied with the heat exchanger testes without paint and with black paint. The air velocity entering the channel was measured with a hot wire anemometer. In order to evaluate the chimney effect, the heat exchanger was testes in a open ambient. This situation simulates its operational conditions when installed on the freezer system. The variables collected in the experimental procedures was gathered in the form of dimensionless parameters as Nusselt, Rayleigh, Grashof and Prandtl numbers, and dimensional parameters of the convection. The results showed that the highest ...

1997-07-01

18

Methodology for sizing, energy analysis and selection of equipment for a biomass gasifier to drive an internal combustion engine; Metodologia de dimensionamento, analise energetica e selecao de equipamentos de um gaseificador de biomassa para o acionamento de um motor de combustao interna  

Energy Technology Data Exchange (ETDEWEB)

Alter both oil crisis, of 1973 and 1979, a bad effect of the elevated costs and continuously increment of the oil prices was noted, for this reason, the interest for renewable energies sources widely available in developing countries was increased. All over the world, governments have formulated main objectives for energies savings and search for friendly technologies, taking into account the effects related with the environment. The imminent scarcity of fossil fuels has made humanity the rational use of primary energies, as a result of these; new plants with improved technology have been conceived taking into account energy savings and efficiency improvement. In this context, biomass gasification technologies are important, since they consist in techniques of parallel production of electricity and heat from just one fuel. This work consists in the development of a gasifier down draft of 100 kW for an internal combustion engine, which includes its sizing process and its energy ...

2006-07-01

19

Energy analysis of a solar pre-water heating system; Analise energetica de um sistema de pre-aquecimento solar de agua  

Energy Technology Data Exchange (ETDEWEB)

Several technological alternatives have been studied taking into consideration that one of the biggest problems of the electric power companies is to provide electric power during the peak consumption periods, which largest contribution to the increase of the demand comes from the residential sector, especially by the use of electric showers. One of the most promising alternatives is the pre-water heating system for reduced power showers, developed by Universidade de Campinas and Companhia Paulista de Forca e Luz. The goal of this system is basically to reduce demand during the peak periods, in order to avoid heavy investments by the electric power companies in generation, transmission and distribution of electric power directed to low acquisitive power customers, a sector in which the electric power price is not enough to recover such investments. The objective of this paper is to evaluate the total energy required in the construction of one of these systems and compare it to the ...

1996-12-31

20

Effects of holmium laser on dental structure in vivo: thermal evaluation and histological analysis on pulpal tissue; Efeitos in vivo do laser de holmio em estrutura dental: monitoracao termica e analise histologica do tecido pulpar  

Energy Technology Data Exchange (ETDEWEB)

Previous in vitro studies have demonstrated that Ho:YLF laser is capable of inducing physical and chemical changes on dental surfaces treated for caries prevention. The temperature in the pulp chamber was in vitro evaluated to as a function of the power and frequency of the laser irradiation. The purpose of this work is to verify the occurrence of pulp inflammation after Ho:YLF laser irradiation using different parameters in rabbits' teeth. The premolars and molars of ten rabbits (NZB) were divided in two groups according to the irradiation energy values of a Ho:YLF laser prototype operating at 2.065{mu}m wave length, frequency of O,5Hz and pulse length of 250{mu}s. An group A teeth were irradiated with using ten pulses of 334mJ/pulse of a Ho:YLF laser prototype operating at O.5Hz, and group B, with 512mJ/pulse. Animals were killed by transcardiac perfusion and the samples were prepared for histopathological analysis. The in vitro temperature monitoring revealed an increase of ...

2001-07-01

 
 
 
 
21

Effect of economic indicators and uncertainties on the selection of a production strategy; Analise da influencia de indicadores economicos e incertezas na escolha da estrategia de producao  

Energy Technology Data Exchange (ETDEWEB)

The decision of a firm to make investments on petroleum fields depends on the expected economic performance and on the firm economics context and on country economic and regulatory constraints. Traditionally, the Net Present Value (NPV) has being used for decision criterion as a measure of profitability of investments. The other indicators are used to help investment decision, because, according to the priorities established by the firm, only one indicator may not be sufficient. On this paper we will show production strategies considering a set of economic indicators: NPV, actualized Np, Return on investment (ROI), Equivalent Present Value (EPV), Cost Benefit, and NPV/Np ratio. The use of different economic indicators permits capture different aspects from in a decision process, i.e., each indicator or a set of economic measures may result in a different perspective, that will influence the decision manager. It is important to emphasize the use of more than one indicators may been ...

2004-07-01

22

Analysis of coupled neutron-gamma radiations, applied to shieldings in multigroup albedo method; Analise das radiacoes neutron e gama acopladas, aplicada a blindagem com varias camadas pelo metodo multigrupo do albedo  

Energy Technology Data Exchange (ETDEWEB)

The principal mathematical tools frequently available for calculations in Nuclear Engineering, including coupled neutron-gamma radiations shielding problems, involve the full Transport Theory or the Monte Carlo techniques. The Multigroup Albedo Method applied to shieldings is characterized by following the radiations through distinct layers of materials, allowing the determination of the neutron and gamma fractions reflected from, transmitted through and absorbed in the irradiated media when a neutronic stream hits the first layer of material, independently of flux calculations. Then, the method is a complementary tool of great didactic value due to its clarity and simplicity in solving neutron and/or gamma shielding problems. The outstanding results achieved in previous works motivated the elaboration and the development of this study that is presented in this dissertation. The radiation balance resulting from the incidence of a neutronic stream into a shielding composed by ...

2002-07-01

23

Study of the mineral variation of two varieties of pigeonpea (Cajanus cajan (L.) Millsp) submitted to different doses of fertilizers by the neutron activation analysis; Acompanhamento da variacao mineral de duas cultivares de guandu (Cajanus cajan (L.) Millsp) submetidas a diferentes doses de fertilizantes, pelo metodo de analise por ativacao com neutrons  

Energy Technology Data Exchange (ETDEWEB)

Instrumental neutron activation analysis (INAA) followed by gamma-ray spectrometry was used to determine the concentrations of As, Ca, Co, Cr, Cu, Eu, Fe, K, La, Mg, Mn, Mo, Na, Pr, Sb, Se, Th, U, V and Z, in 82 leaf samples belonging to two cultivars of pigeonpea (Cajanus cajan (L.) Millsp). Pigeonpea, an easy cultivation legume species, probably originated from Africa and adapted to brazilian conditions, is a very promising and unconventional source of food, mainly to the grain production intended for human feeding, and that even can be used in flour products. It is an excellent proteic supplement for ruminants, due to its large potential of forage production and its high nutritive value, or in addition it can be used in the recuperation of exhausting soils either by means of its utilization as green manure or by taking free Nitrogen from the atmosphere to produce nitrates which can be utilized by the plants. However, in spite of the several possibilities and increasing utilization ...

2001-07-01

24

Mechanodynamical analysis of nickel-titanium alloys for orthodontics application; Analise mecanodinamica de ligas de niquel-titanio para aplicacao ortodontica  

Energy Technology Data Exchange (ETDEWEB)

Nickel-titanium alloys may coexist in more than one crystalline structure. There is a high temperature phase, austenite, and a low temperature phase, martensite. The metallurgical basis for the superelasticity and the shape memory effect relies in the ability of these alloys to transform easily from one phase to another. There are three essential factors for the orthodontist to understand nickel-titanium alloys behaviour: stress; deflection; and temperature. These three factors are related to each other by the stress-deflection, stress-temperature and deflection-temperature diagrams. This work was undertaken with the objective to analyse commercial nickel-titanium alloys for orthodontics application, using the dynamical mechanical analyser - DMA. Four NiTi 0,017 X 0,025'' archwires were studied. The archwires were Copper NiTi 35 deg C (Ormco), Neo Sentalloy F200 (GAC), Nitinol Superelastic (Unitek) and NiTi (GAC). The different mechanodynamical properties such as ...

2002-07-01