Relações entre condutividade hidráulica, transmissividade, condutância longitudinal e sólidos totais dissolvidos para o aquífero livre de Caçapava do Sul (RS), Brasil

A água subterrânea é um importante recurso ao abastecimento público, principalmente para comunidades periféricas em grandes cidades ou pequenos municípios, onde a instalação ou prolongamento de sistemas de distribuição são economicamente inviáveis. Estudos voltados à análise da vulnerabilidade de aquíferos são relevantes para subsídio a políticas públicas em saneamento básico e preservação ambiental. Este estudo contou com o cadastro de 23 poços rasos localizados no município de Caçapava do Sul (RS), onde foram realizadas medidas de resistividade elétrica e cargabilidade por meio de geofísica, e medidas diretas de condutividade hidráulica e sólidos totais dissolvidos. A análise estatística dos dados demonstrou diversos graus de correlação entre parâmetros, basicamente condicionados a fatores geológicos como porosidade, permeabilidade e sólidos totais dissolvidos.

Estudo das propriedades de troca iônica e/ou adsorção da celulose e celuloses modificadas

In this work it was studied the capacity of cellulose and chemically modified celluloses (carboxymethylcellulose, cellulose phosphate and oxicellulose) to adsorb copper(II) cations of aqueous and non aqueous solutions. The influence of the principal physical chemical parameters on the adsorption process was examined using the batch adsorption method and copper(II) perchlorate solutions, the maximum adsorption capacity determined for adsorbents were as follows (mol.g(-1)): cellulose, 0.54 . 10(-5); carboxymethylcellulose, 1.28 . 10(-4); cellulose phosphate, 1.12 . 10(-4); oxicellulose, 0.38 . 10(-4).

Condutividade elétrica na solução de embebição de sements de soja. I. Efeito do genótipo

During the period from October/92 to September/94 experiments were carried out at the Seed Laboratory, FCAV/UNESP, Jaboticabal, SP, Brazil, using soybean seeds of different genotypes in order to evaluate the effect of genotype on the electrical conductivity (bulk conductivity) of soaked seeds. Seed moisture content (105+/-3 degrees C, 24 h), standard germination (four 50-seed samples, paper towel, 30 degrees C), and vigor-accelerated aging (42 degrees C, 48 h) were first determined. Undamaged soybean seeds were soaked in deionized water (four 50-seed samples, 75 ml, 25 degrees C, 24 h) and electrical conductivity (mu mhos.cm(-1).g(-1)) was measured. Significant differences in conductivity were observed among genotypes having the same pattern of germination and vigor. The results have showed that electrical conductivity can be significantly influenced by genotype.

Concentração de sais da soluçtiao avaliada pela condutividade elétrica na zona radicular do crisântema sob irrigação por gotejamento

The effects of salt concentration levels in electrical conductivity (EC) were evaluated in chrysanthemum root, cultivated in substrate using two sampling methods, under greenhouse conditions. The experiment was carried out in Paranapanema, São Paulo using the experimental design in randomized blocks and four replications. The treatments consisted of eight sampling periods of substrate solutions in pots: 7, 14, 21, 28, 35, 42, 49 and 56 days after strike root and five salt concentration levels of applied saline solution: 1.42; 1.65; 1.89; 2.13 and 2.36 dS m -1 in the vegetative period and during the reproduction period of flower budding: 1.71; 1.97; 2.28; 2.57 and 2.85 dS m -1. The substrate solution EC monitoring was done using two methods: solution extractors and 1:2 water diluted solution. The use of solution extractors and 1:2 water diluted solution allowed substrate solution EC monitoring along the culture cycle; the amount of salt concentration applied in the substrate caused the substrate salinity increase; the method using solution extractors presented higher EC values in the substrate.

Condutividade hidráulica e resistência à penetraçao do solo influenciada por diferentes sistemas de manejo

Soil management measures that increase the efficiency of organic matter cycling and maintain favorable soil structure are needed for improving soil quality. On the other hand, soil structure degradation due to inadequate soil management systems is widespread. Among the indicators of soil physical quality, saturated hydraulic conductivity and penetration resistance are thought to be sensitive to soil management system. The aim of this work was to study the influence of soil tillage system and organic fertilization on selected soil physical properties after the first year of treatment. The field work was conducted in Selviria, MS, Brazil on an Oxisol. The experimental design was randomized complete blocks with split-plots, with 12 treatments and 4 repetitions. Tillage treatments included conventional ploughing (CT) and direct drilling (DD). Fertilizer treatments were: 1) manure, 2) manure plus mineral, 3) traditional mineral 4) plant residues of Crotalaria juncea, 5) plant residues of Pennisetum americanum and 6) control plot. The plots were cropped to bean in winter and to cotton in summer, and both cultures were irrigated. After one year no significant differences between treatments in mechanical resistance and porosity were found. However, saturated hydraulic conductivity and infiltration were higher in the conventional tillage treatment at the 0.00-0.10 m depth. Moreover, an improvement in soil physical condition by organic fertilizers was shown.

Hidrogeoquímica do aqüífero guarani na área urbana de ribeirão preto (SP)

This work evaluated the hydrogeochemistry of the Guarani Aquifer in the urban area of Ribeirão Preto, São Paulo State. Thirty one sampling points were established and it was carried out field campaigns in 7 and 8 July 2005, analyzing the following parameters: conductivity, temperature, pH, turbidity, color, dry residue, dissolved oxygen, Ca2+, Mg2+, Na+, K+, Fe3+, Al3+, HCO3-, SO42-, PO43-, NO3-, Cl- and F-. The results indicated that the groundwaters in the urban area of Ribeirão Preto pH possess slightly acid, low conductivity, turbidity, color and dissolved oxygen inside the limits established for drinking waters. The ionic composition indicated that the groundwaters have low cations and anions concentration, being they classified as soft water and calcium-bicarbonated. Statistical tests suggested that conductivity and pH are controlled for the calcite dissolution (CaCO3) during the water/rock interaction process. Besides, it is possible to conclude that the high NO3- and PO43- concentrations found in the groundwater in the urban area of Ribeirão Preto are originated due to anthropogenic activities.

Testes de envelhecimento acelerado e de condutividade elétrica em sementes de Dictyoloma vendellianum A. Juss.

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Condutividade elétrica da solução nutritiva e acúmulo de macro e micronutrientes no cultivo de crisântemo

The study of growth and uptake of nutrients is important to determine the times of increased demand in order to schedule the fertigation. The present research was developed with the objective of evaluating the effects of different levels of electrical conductivity on growth and accumulation of nutrients in chrysanthemum plants under greenhouse conditions. The electrical conductivity levels on the applied solution were 1.42, 1.65, 1.89, 2.13 and 2.36 dS m-1 (bud vegetative stage); 1.71, 1.97, 2.28, 2.57 and 2.85 dS m-1 (bud stage). The dry mass of the aerial portion of the plant and the contents of macronutrients and micronutrients were determined every 14 days. The nutrient accumulation in chrysanthemum plant showed similar trend as compared to dry matter accumulation. The nutrients presented the following order of absorption: K>N>Ca>Mg>P>S (1425, 892, 184, 150, 110 and 59 mg plant-1) and Fe>Zn>B>Mn>Cu (2254, 2219, 1725, 1287, 210 μg plant-1). The content of most nutrients increased with increase in electrical conductivity of the solution, without salt effect up to EC of 2.85 dS m-1.

Avaliação dos efeitos da crotoxina isolada do veneno de serpente Crotalus durissus terrificus sobre a transecção do nervo ciático de ratos: avaliação histológica da formação do neuroma e capacidade de interferir com a condutividade nervosa (dor)

Pós-graduação em Medicina Veterinária - FMVZ

Estudo do comportamento magnético de plasma durante o processo de implantação iônica por imersão em plasma

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Medidas de ressonância de spin eletrônico (RSE) em polianilina dopada com plastificante e de condutividade a.c. e RSE em óxidos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Síntese e caracterização do sistema vítreo (1-x) NaPO 3 – (x)WO 3

Pós-graduação em Ciência dos Materiais - FEIS

Estudo do comportamento coloidal de suspensão de fibra de celulose, carbonato de cálcio, amido catiônico: variação da força iônica e do pH

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização da condutividade hidráulica do embasamento cristalino alterado saturado na região metropolitana de São Paulo

Pós-graduação em Geociências e Meio Ambiente - IGCE

Níveis de condutividade elétrica da solução do substrato em crisântemo de vaso, em ambiente protegido

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)