979 resultados para CA-2


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The interaction of emeraldine base (PANI-EB) with silver and gold colloids was probed by using Surface-Enhanced Resonance Raman Scattering (SERRS) at 3 different exciting radiations. Due to the great sensitivity of SERRS technique the detection limit of PANI-EB concentration was ca. 2 x 10(-7) mol L(-1) in Ag and Au colloidal suspensions. The UV-vis-NIR spectra of metal colloids in function of PANI-EB concentrations showed that gold colloids present a higher degree of aggregation than silver colloids. SERRS of PANI-EB on metal colloids allowed the study of the polymeric species formed primarily on the metallic surface. The polymer formed after the adsorption of PANI-EB on metallic nanoparticles is strongly dependent on the nature of the metal colloids. The oxidation of PANI-EB to pernigraniline occurred for silver colloids, while a doping process of PANI-EB on Au nanoparticles was evidenced through the observation of the characteristic SERRS spectrum of emeraldine salt at 1064nm.

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Anneberg är ett område i Danderyds kommun där det skall beredas plats för ett nytt bostadsområde. Området skall bebyggas med flerbostadshus, gruppbostäder och ett sjukhem. Denna förstudie beskriver översiktligt 3 systemförslag som kan användas för uppvärmning av husen i bostadsområdet Anneberg. Målsättningen är att presentera uppvärmningssystem som visar hur solenergi kan användas för att öka värmepumpsystemens värmefaktor.Systemen modellerades i TRNSYS och systemfunktionen samt energiflöden simulerades. Simulerade prestanda för tre olika typer av uppvärmningssystem redovisas. System A är ett vanligt värmepumpsystem med borrhål och värmepump placerad i ett flerfamiljshus av typ 3. System B liknar system A, men har kompletterats med en glasad solfångare för varmvattenberedning. System C är en lösning som kan tillämpas för större byggnader eller för ett område med flera byggnader. Systemet har ett gemensamt värmelager och ett kulvertsystem som förbinder byggnaderna med värmelagret. I varje ansluten byggnad installeras sedan en värmepump och en oglasad solfångare.Simuleringsresultatet redovisas som en värmefaktor för systemets fem första driftår. System A får en värmefaktor på mellan 2,3 och 2,7 för de första 5 driftåren. System B får en värmefaktor på mellan 3,4 och 3,7 och system C får en värmefaktor på mellan 4,0 och 4,5. Studien visar att det går att öka värmefaktorn på en värmepumpanläggning från ca 2,5 upp till 4 eller 4,5 genom att komplettera anläggningen med solfångare och värmelager. Detta innebär att elförbrukningen minskar från att vara ca 40 % av värmebehovet ned till under 25 % av värmebehovet. Det bör således finnas en potential för att komplettera värmepumpanläggningar med solvärme. Vilket utförande som kan bli ekonomiskt intressant kan inte bedömas i denna förstudie. I förstudien visas enbart resultatet för tre enstaka systemutföranden. Inga parametervariationer (tex solfångaryta, antal borrhål och avstånd mellan borrhålen) är utförda. En sådan systemoptimering bör göras med förstudien som utgångsläge.

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A protena S100B pertence famlia S100 de protenas ligantes de Ca+2. Sua expresso d-se primariamente em astrcitos, os quais tambm secretam esta protena, exercendo um papel trfico sobre as clulas vizinhas. A adio de S100B tem promovido a sobrevivncia de neurnios em cultura e, recentemente, tem sido proposto um papel protetor da S100B contra a excitoxicidade. Neste trabalho investigamos a liberao de S100B na presena de alta concentrao de glutamato. A secreo de S100B em astrcitos de ratos em cultura foi quantificada, pelo mtodo de ELISA, durante 24 horas aps uma privao de soro de 30 minutos (condio estimulada) ou no (condio basal). A integridade dos astrcitos foi analisada por ensaios de excluso de azul de tripan e medida da LDH. Glutamato (1 mM) no teve efeito sobre a secreo basal de S100B, mas diminuiu a liberao 1h depois da privao de soro. A privao de soro que estimulou a liberao de S100B foi dependente de sntese protica e reduzida por Rp-AMPc e H-89, sugerindo o envolvimento da via AMPc/PKA, possivelmente sobre o elemento sensvel ao AMPc no gene de S100B. Alm disso, a privao de soro foi acompanhada por um aumento transitrio do contedo intracelular de AMPc. Nossos resultados sugerem que o proposto papel neurotrfico da S100B, pelo menos em cultura de astrcitos hipocampais, poderia estar prejudicado por altos nveis de glutamato. No est claro ainda se o efeito do glutamato medeado por receptores. Na tentativa de investigar o mecanismo envolvido usamos inibidores do transporte de glutamato e agonistas de glutamato. Os resultados indicam que ambos receptores metabotrpicos do Grupo I/II e transportadores de glutamato esto envolvidos no decrscimo da secreo de S100B induzida pelo glutamato.

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Nesta tese da especialidade de Hidrogeologia, apresentado um primeiro levantamento vulcano-estratigrfico da ilha da Madeira. Os trabalhos de campo permitiram definir, at agora, sete unidades geolgicas principais, descritas da mais antiga para a mais recente: 1- Complexo Vulcnico Antigo (CA) 2- Calcrios Marinhos dos Lameiros - S. Vicente (CM) 3- Depsito Conglomertico-Brechide (CB) 4- Complexo Vulcnico Principal (CP) 5- Complexo Vulcnico S. Roque/Paul (SRP) 6- Episdios Vulcnicos Recentes (VR) 7- Depsitos de Vertente (dv), Fajs (fj), Quebradas (q), Depsitos de Enxurrada Recentes (dr), Areias de Praia (ap), Dunas Fsseis (df), Terraos (t), e Aluvies (a) A caracterizao climtica da ilha da Madeira foi feita com base nos dados recolhidos em 27 pontos de observao climatolgicos, dos quais 14 so estaes meteorolgicas e 13 so postos udomtricos, o que representa uma densidade de 1 ponto de observao/27 km2. Constatou-se que a variao da precipitao com a altitude no era linear e dependia da orientao das vertentes. Efectuou-se o balano hdrico sequencial dirio, com base nos valores de precipitao mdia diria, registados no Paul da Serra, durante os ltimos 15 anos hidrolgicos. Pretendeu-se quantificar a precipitao oculta na vegetao tpica da ilha da Madeira, de modo a poder avaliar a contribuio daquele tipo de precipitao para os recursos hdricos subterrneos, e, ainda, determinar qual o potencial daquele recurso natural, como contribuio importante s fontes tradicionais de abastecimento de gua ilha. Para o efeito, procedemos a dois tipos principais de medio: medio directamente sob a vegetao de altitude da Madeira, o urzal, que se desenvolve entre os 1200 e os 1600 m de altitude, e construo de aparelhos constitudos por obstculos artificiais, de modo a interceptarem as gotculas de gua contidas no nevoeiro. Pela sua importncia, os resultados obtidos justificam o desenvolvimento futuro deste estudo. A caracterizao hidrodinmica das formaes da ilha da Madeira baseou-se nas observaes feitas no interior das galerias e tneis em escavao, na anlise dos registos de caudais de galerias e nascentes e na interpretao de ensaios de bombeamento dos furos de captao. Os dados evidenciam a grande heterogeneidade e anisotropia caractersticas do meio vulcnico. As transmissividades vo desde 11 m2/d at 25 766 m2/d. A caracterizao hidrogeoqumica permitiu identificar um grupo de 5 guas termais, emergentes em falhas, no Complexo Antigo, com caractersticas muito prprias, bastante distintas das restantes, que representam, quer em quantidade, quer em volume de caudais captados, a grande maioria das guas da ilha da Madeira. O principal fenmeno mineralizador das guas a hidrlise de minerais silicatados, verificando-se, nas guas dos furos, nas das nascentes de altitude e nas situadas prximo do litoral, o efeito da contaminao de sais de origem marinha. A partir dos dados hidrogeolgicos obtidos, foi possvel elaborar um modelo conceptual de funcionamento hidrogeolgico para a ilha da Madeira, que, apesar de possuir alguns elementos comuns, , no seu conjunto, diferente dos modelos conhecidos para outras ilhas vulcnicas, nomeadamente, Canrias, Reunio, Havai e Polinsia Francesa.

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A 140,0 kDa lectin was purified and characterized from the mushroom Clavaria cristata. The purification procedures from the crude extract of the mushroom comprised gel filtration chromatography on Sephacryl s200 and ion exchange on Resource Q column. The purified lectin agglutinated all types of human erythrocytes with preference for trypsinized type O erythrocytes. The haemagglutinating activity is dependent of Ca 2+ ions and was strongly inhibited by the glycoprotein bovine submaxillary mucin (BSM) up to the concentration of 0, 125 mg/mL. The C. cristata lectin (CcL) was stable in the pH range of 2,5-11,5 and termostable up to 80 C. CcL molecular mass determined by gel filtration on a Superose 6 10 300 column was approximately 140,3 kDa. SDS polyacrilamide gel electrophoresis revealed a single band with a molecular mass of approximately 14,5 kDa, when the lectin was heated at 100 C in the presence or absence of -mercaptoethanol. CcL induced activation of murine peritoneal macrophages in vitro resulting in the release of nitric oxide (NO), reaching the maximum production at 24 h. In experimental paw oedema model in mice, CcL showed proinflammatory activity being able to induce oedema formation. Cell viability of HepG2, MDA 435 e 3T3 cell lines was examined after 72 h of incubation with CcL in different concentrations (0,5-50 g/mL). CcL inhibited HepG2 cells growth with an IC50 value of 50 g/mL. In the present work, the observed immunomodulatory and antiproliferative effects indicate CcL as a possible immunomodulator compound, interfering in the macrophages immune response, taking possible anti-parasitic, anti-tumoral effects or diagnostic and/or therapeutic

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Portland-polymers composites are promising candidates to be used as cementing material in Northeastern oil wells of Brazil containing heavy oils submitted to steam injection. In this way, it is necessary to evaluate its degradation in the commonly acidizind agents. In addition, to identify how aggressive are the different hostile environments it is an important contribution on the decision of the acidic systems to be used in. It was investigated the performance of the Portland-polymer composites using powdered polyurethane, aqueous polyurethane, rubber tire residues and a biopolymer, those were reinforced with polished carbon steel SAE 1045 to make the electrochemical measurements. HCl 15,0 %, HCl 6,0 % + HF 1,5 % (soft mud acid), HCl 12,0 % + HF 3,0 % (regular mud acid) and HAc 10 % + HF 1,5 % were used as degrading environment and electrolytes. The more aggressive acid solution to the plain Portland hardened cement paste was the regular mud acid, that showed loss of weight around 23.0 %, followed by the soft mud acid, the showed 11.0 %, 15.0 % HCl with 7,0 % and, at last the 10.0 % HAc plus HF 1.5 % with just 1.0 %. The powdered polyurethane-composite and the aqueous polyurethane one showed larger durability, with reduction around 87.0 % on the loss of weight in regular mud acid. The acid attack is superficial and it occurs as an action layer, where the degraded layer is responsible for the decrease on the kinetic of the degrading process. This behavior can be seen mainly on the Portland- aqueous polyurethane composite, because the degraded layer is impregnated with chemically modified polymer. The fact of the acid attack does not have influence on the compressive strength or fratography of the samples, in a general way, confirms that theory. The mechanism of the efficiency of the Portland-polymers composites subjected to acid attack is due to decreased porosity and permeability related with the plain Portland paste, minor quantity of Ca+2, element preferentially leached to the acidic solution, wave effect and to substitute part of the degrading bulk for the polymeric one. The electrolyte HAc 10 % + HF 1,5 % was the least aggressive one to the external corrosion of the casing, showing open circuit potentials around +250 mV compared to -130 mV to the simulated pore solution to the first 24 hours immersion. This behavior has been performed for two months at least. Similar corrosion rates were showed between both of the electrolytes, around 0.01 μA.cm-2. Total impedance values, insipient arcs and big polarization resistance capacitive arcs on the Nyquist plots, indicating passivity process, confirm its efficiency. In this way, Portlandpolymers composites are possible solutions to be succeed applied to oilwell cementing concomitant submitted to steam injection and acidizing operation and the HAc 10,0 % + HF 1,5 % is the less aggressive solution to the external corrosion of the casing

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Fundao de Amparo Pesquisa do Estado de So Paulo (FAPESP)

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Fundao de Amparo Pesquisa do Estado de So Paulo (FAPESP)

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Fundao de Amparo Pesquisa do Estado de So Paulo (FAPESP)

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Fundao de Amparo Pesquisa do Estado de So Paulo (FAPESP)

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To evaluate the growth and pattern of nutrient absorption (N, P, K, Ca, Mg and S amongst others) in three berry cultivars (treatments), four plants by treatment in different phonological stages were harvested. The experiment was arranged in randomized design of factorial 3x5 with three replicates. There cultivars were used FM Shima-Miura, IZ 56/4 and Miura and above ground biomass was harvested in five occasions 45, 60, 75, 90 and 115 days after plantation. It was observed that the accumulation of nutrients presented different pattern and cv. IZ 56/4 was superior compared with PM Shima-Miura for N, P, K, Ca, Mg and S and N, P, K and S for Miura. For example, the accumulation of N expressed on mg plant"(1) per berry plant cultivar PM Shima-miura, IZ 56/4 and Miura was respectively 4,21; 8,14 and 5,56, for K 2,71; 5,22 and 2,64 and for Ca 2,47; 4,52 and 3,59.

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Fundao de Amparo Pesquisa do Estado de So Paulo (FAPESP)

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Availability of good quality water has been reduced vertiginously, over the last decade, in the world. In some regions, the water resources have high concentration of the dissolved salts, these characteristics of the water make it s use impossible. Water quality can be a limitation for irrigated agriculture, principally in regions of arid or semiarid climate where the water resources are generally saline and are exposed at high evaporation ratio. For that reason, precipitation of the salts occurs near the soil surface and those salts themselves cumulate in the vegetal tissue, reducing the soil fertility and crop production. The adoption of tolerant crop to the water salinity and soil salinity, adaptable to the climatic conditions is other emergent necessity. This work had the goal of studying the effects of four salinity levels of the irrigation water salinity and use of mulch, dried leaves of Forest mangrove (Acacia mangiumWilld), in cultivated soil with amaranth (Amaranthus cruentus, BRS Alegria variety), in greenhouse. It was utilized the transplant of plants to PVC columns, containing 30 kg of silty loam soil, 10 days after emerging, with space of 50 x 50 cm between lines. Treatments were composed by combination of four levels of salinity (0.147; 1.500; 3.000 e 4.500 dS m-1), obtained by addition NaCl (commercial) to irrigation water and soil with and without protection, by mulch. A factorial system 4 x 2 was used with four repetitions, totalizing 32 parcels. The concentrations of nutrients in soil solution have been evaluated, in the dry matter of the vegetal tissue (roots, stem, leaves and raceme residue), at the end of the vegetative cycle. The use of soil protection reduced time for the beginning inflorescence of plants, at the same time, the increase of the salinity delayed this phase of amaranth development. The use of the mulch effectively increased the height, stem diameter, area of the larger leaf, humidity and dry matter content and amaranth grain production. The vegetal species showed salinity tolerance to experimented levels. The adopted treatments did not affect the pH values, exchangeable cation contents, electrical conductivity of soil solution (EC1:5) and saturated extract (ECSE), and Ca+2, Mg+, Fe+2 and Mn+2 contents, in the soil solution. The increase of the salinity concentration in the irrigation water inhibited the mineralization process of the organic matter (OM) and, consequently, the efficiency in the its utilization by plants, at the same time, produced increase in the values of the exchangeable sodium percentage (ESP), sodium adsorption ratio (SAR) and potassium adsorption ratio (PAR), in the soil solution. Therefore, the use of the mulch did not affect the first three parameters. The protein and nutrient contents: K+, Ca+2, P, Mg+2 e Cu+2, in amaranth grains, were improved by tillage condition. The raceme residues showed chemical/nutritional composition that makes advantageous its application in animal ration. In this context, it follows that amaranth tolerate the saline stress, of the irrigation water, until 4.500 dS m-1, temperature and relative humidity of the air predominant in the experimental environment

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Environmental impacts are defined as the processes of social and ecological changes caused by nuisance ambient. In agriculture are diverse, and the intensive use of land and inappropriate agricultural practices causes negative effect on the environment besides affecting crop productivity and quality of life of man. So this study was objective to analyze parameters indicators of environmental impacts in the Cruzeta the Discrict Irrigation. During the period July 2007 to March 2008 samples were collected in lot 01 and 02 of the irrigation district. The monitoring was conducted in four sampling points, three (3) located in the irrigation channels and 1 (one) located in a cacimbo. Were monitored pH, CE, STD, SS, NO3-, OD, DT, PST, RAS, CT, Ca+2, Mg+2, Na+ and K+ and heavy metals. Analysis was performed, soil fertility, determining the infiltration rate, moisture content of soil and flow measurement. The results showed that the parameters considered most effective in evaluating the indicators of environmental impacts were: Suspended solid, turbidity, dissolved oxygen and Coliform termotelerantes. The concentrations of nitrate were below the limit established by CONAMA (2005). High levels of STD were found in the point P4. The risk of salinity in cacimbo Lot 02, the water was classified as Class II, or medium risk of salinity in the remaining points was classified as Class I. The iron and aluminum were found high concentrations in four sampling points independent of the dry or rainy. On the ground, found high levels of phosphorus in both samples collected in the batch 01, as the lot 02. The pH levels found in samples of soil, the soil can be classified as neutral and moderate alkalinity. The high infiltration rate obtained in the tests performed in lots 01 and 02 indicated the high permeability of soil at these points

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Fundao de Amparo Pesquisa do Estado de So Paulo (FAPESP)