Influence Of Earth's Conductivity And Permittivity Frequency Dependence On Overhead Transmission Lines: Analysis For The One - Conductor Case [influência Da Dependência De Parâmetros Do Solo Com A Frequência Na Modelagem De Linhas Aéreas De Transmissão: Caso De Condutor único]

In this paper the influence of earth's conductivity and permittivity frequency dependence are evaluated when calculating transversal and longitudinal transmission lines' parameters. The aim is to compare results calculated from the complex plane method and Carson's modified expressions on longitudinal parameters and also between Carson's modified potential-coefficient correction factors and results from approximations methods for transversal admittance parameters. The importance of properly considering the frequency-dependent soil model is presented for oneconductor case, in order to compare the longitudinal and transversal parameters considering the earth's conductivity and permittivity frequency dependence soil model in relation to the common soil representation with a constant conductivity and a permittivity that can be neglected assuming a low frequency approximation.225506522Arismunandar, A., Capacitive correction factors for transmission lines to include finite conductivity and dielectric of the earth (1963) Proceedings of the AIEE Summer General Meeting and Nuclear Radiation Effects Conference, pp. 436-455. , Toronto, Ont., Canadá, June 16-21, 1963Carson, J.R., Wave propagation in overhead wires (1926) Bell System Technical Journal, 5, p. 539554. , 1926Deri, A., Tevan, G., Semlyen, A., Castanheira, A., The complex ground return plane, a simplified model for homogeneous and multi-layer earth return (1981) IEEE Trans. PAS, 100 (8), p. 36863693. , 1981Dwight, H.B., Skin effect in tubular and flat conductors (1918) AIEE Transactions, 37 (2 PART), pp. 139-1403. , 1918Nakagawa, M., Further studies on wave propagation along overhead transmission lines: Effects of admittance correction (1981) IEEE PES Winter Meeting, , Atlanta, Georgia, 1981Portela, C., Frequency and transient behavior of grounding systems I-physical and methodological aspects (1997) Proceedings 1997 International Symposium on Electromagnetic Compatibility, pp. 380-384. , August Agosto 1997, United StatesEUAPortela Carlos, Measurement and modeling of soil electromagnetic behavior (1999) IEEE International Symposium on Electromagnetic Compatibility, 2, pp. 1004-1009Portela, C., Grounding requirement to assure people and equipment safety against lightning (2000) Proceedings IEEE 2000 International Symposium on Electromagnetic Compatibility, pp. 969-974. , August 2000, Washington DC, United StatesEUAPortela, C.M., Gertrudes, J.B., Tavares, M.C., Pissolato, J., Earth conductivity and permittivity data measurements: Influence in transmission line transient performance (2006) Electric Power Systems Research, 76 (11), pp. 907-915. , DOI 10.1016/j.epsr.2005.11.006, PII S0378779605002658Portela, C., Tavares, M.C., Pissolato, J., Accurate representation of soil behaviour for transient studies (2003) IEE Proceedings on Genereation, Transmission and Distribution, 150 (6), pp. 734-744. , Nov. 2003Rachidi, F., Nucci, C.A., Ianoz, M., Mazzetti, C., Influence of a lossy ground on lightning-induced voltages on overhead lines (1996) IEEE Trans. Electromagn, 38 (2). , Compatibility IEEE Transactions on EMC, Agosto, 1996Sunde, E.D., (1948) Earth Conduction Effects in Transmission Systems, , Princeton, New Jersey: Van Nostrand, 1948Tesche, F.M., Comparison of the transmission line and scattering models for computing the HEMP response of overhead cables (1992) IEEE Trans. Electromagn. Compatibility, 34. , May 1992Wise, W.H., Effect of ground permeability on ground return circuits (1931) Bell System Technical Journal, 10, pp. 472-484. , New York, Jul. 1931Wise, W.H., Propagation of high-frequency currents in ground return circuits (1934) Proceedings, Institute of Radio Engineers, 22, pp. 522-527. , New York, N. Y., Apr. 193

Molecular analysis of the bacterial diversity in a specialized consortium for diesel oil degradation Análise molecular da diversidade bacteriana de um consórcio degradador de óleo diesel

Diesel oil is a compound derived from petroleum, consisting primarily of hydrocarbons. Poor conditions in transportation and storage of this product can contribute significantly to accidental spills causing serious ecological problems in soil and water and affecting the diversity of the microbial environment. The cloning and sequencing of the 16S rRNA gene is one of the molecular techniques that allows estimation and comparison of the microbial diversity in different environmental samples. The aim of this work was to estimate the diversity of microorganisms from the Bacteria domain in a consortium specialized in diesel oil degradation through partial sequencing of the 16S rRNA gene. After the extraction of DNA metagenomics, the material was amplified by PCR reaction using specific oligonucleotide primers for the 16S rRNA gene. The PCR products were cloned into a pGEM-T-Easy vector (Promega), and Escherichia coli was used as the host cell for recombinant DNAs. The partial clone sequencing was obtained using universal oligonucleotide primers from the vector. The genetic library obtained generated 431 clones. All the sequenced clones presented similarity to phylum Proteobacteria, with Gammaproteobacteria the most present group (49.8 % of the clones), followed by Alphaproteobacteira (44.8 %) and Betaproteobacteria (5.4 %). The Pseudomonas genus was the most abundant in the metagenomic library, followed by the Parvibaculum and the Sphingobium genus, respectively. After partial sequencing of the 16S rRNA, the diversity of the bacterial consortium was estimated using DOTUR software. When comparing these sequences to the database from the National Center for Biotechnology Information (NCBI), a strong correlation was found between the data generated by the software used and the data deposited in NCBI.<br>O óleo diesel é um composto derivado do petróleo, constituído basicamente por hidrocarbonetos. Condições precárias no processo de transporte e armazenagem desse produto contribuem significativamente para derrames acidentais, ocasionando sérios problemas ecológicos no solo e água, alterando assim toda a diversidade microbiológica do ambiente. A estratégia de clonagem e sequenciamento do gene 16S rRNA é uma das técnicas moleculares que permitem estimar e comparar a diversidade microbiana de diferentes amostras ambientais, sejam elas impactadas ou não. O objetivo deste trabalho foi estimar a diversidade de microrganismos pertencentes ao domínio Bacteria em um consórcio degradador de óleo diesel por meio de sequenciamento parcial do gene 16S rRNA. Após extração do DNA metagenômico, o material foi amplificado por reação de PCR com oligonucleotídeos iniciadores específicos para o gene 16S rRNA. Os produtos da reação de PCR foram clonados em vetor pGEM T Easy (Promega) e transformados em células competentes de Escherichia coli. O sequenciamento parcial dos clones foi feito com oligonucleotídeos universais do vetor. A biblioteca obtida gerou 431 clones. Todos os clones mostraram similaridade com o filo Proteobacteria, onde as Gammaproteobacteria compreenderam o grupo de maior representatividade, com 49,8 % dos clones, seguida das Alphaproteobacteira, com 44,8 %, e das Betaproteobacteria, com 5,4 %. O gênero Pseudomonas destacou-se como representante com maior frequência de clones na biblioteca, seguido pelos gêneros Parvibaculum e Sphingobium. Após o sequenciamento parcial do gene 16S rRNA, a diversidade bacteriana do consórcio foi estimada utilizando-se o software DOTUR. Essas sequências, quando comparadas com as do banco do National Center for Biotechnology Information (NCBI), mostraram grande correlação entre os dados gerados pelo software utilizado e aqueles depositados no NCBI