Effect of pH on boron adsorption in some soils of Parana, Brazil

Temporary B deficiency can be triggered by liming of acid soils because of increased B adsorption at higher soil pH. Plants respond directly to the activity of B in soil solution and only indirectly to B adsorbed on soil constituents. Because the range between deficient and toxic B concentration is relatively narrow, this poses difficulty in maintaining appropriate B levels in soil solution. Thus, knowledge of the chemical behavior of B in the soil is particularly important. The present study investigated the effect of soil pH on B adsorption in four soils of Parana State, and to correlate these values with the physical and chemical properties of the soils. Surface samples were taken from a Rhodic Hapludox, Arenic Hapludalf, Arenic Hapludult, and one Typic Usthorthent. To evaluate the effect of pH on B adsorption, subsamples soil received the application of increasing rates of calcium carbonate. Boron adsorption was accomplished by shaking 2.0 g soil, for 24 h, with 20 mL of 0.01 mol L-1 NaCl solution containing different concentrations (0.0, 0.1, 0.2, 0.4, 0.8, 1.2, 1.6, 2.0, and 4.0 mg B L-1). Sorption was fitted to non-linear form of the Langmuir adsorption isotherm. Boron adsorption increased as concentration increased. Boron adsorption was dependent on soil pH, increasing as a function of pH in the range between 4.6 and 7.4, although the bonding energy has decreased. Maximum adsorption capacity (MAC) of B was observed in the Arenic Hapludalf (49.8 mg B kg(-1) soil) followed by Arenic Hapludult (22.5 mg kg(-1)), Rhodic Hapludox (17.4 mg kg(-1)), and Typic Usthorthent (7.0 mg kg(-1)). The organic matter content, clay content, and aluminum oxide content (Al2O3) were the soils properties that affecting the B adsorption on Parana soils.

The effect of exogenous fibrolytic enzymes and a ferulic acid esterase-producing inoculant on the fibre degradability, chemical composition and conservation characteristics of alfalfa silage

The objective of this study was to determine the effect of applying fibrolytic enzymes at ensiling, either alone or in combination with a ferulic acid esterase-producing bacterial silage inoculant, on the silage conservation characteristics and nutritive value of alfalfa (Medicago sativa L). Second-cut alfalfa (340 g DM/kg fresh crop) was harvested, wilted, chopped and sub-sampled into 24 batches. Samples were randomly allocated in triplicate to one of four enzyme product treatments supplying endoglucanases and xylanases: none (control), EN1, EN2, EN3; applied alone or in combination with a ferulic acid esterase-producing silage inoculant (FAEI). Treatments were arranged in a 4 x 2 factorial design. All enzyme treatments were applied at 2 ml enzyme product/kg herbage DM, and inoculant was applied at 1 x 10(5) cfu/g fresh herbage. Samples were packed into laboratory-scale silos and stored for 7, 27 or 70 days, and analysed for dry matter (DM) losses, aerobic stability, chemical composition and in vitro ruminal degradability. The use of enzymes did not affect (P>0.05) ensilage DM losses or lactic or acetic acid concentrations after 70 days of ensilage, compared to the control silage. Silage produced using EN1 had lesser neutral detergent fibre (aNDF, P=0.046) and acid detergent fibre (ADF; P=0.006) concentrations than control silage. However, no difference (P>0.05) was observed between the control silage and silage produced with EN1 for aNDF or ADF degradability (NDFD, ADFD). Silages produced with FAEI had greater DM losses (P=0.017) and pH (P<0.001) and lesser NDFD (P=0.019), ADFD (P=0.010) and proportion of lactic acid in the total fermentation products (P=0.006) after 70 days of ensilage, compared to uninoculated silages. The use of fibrolytic enzymes did not have a major effect on the ensilage fermentation of alfalfa, either ensiled alone or with an inoculant. No advantage in ruminal DM or fibre degradability was observed for silages produced with fibrolytic enzymes. The use of a ferulic acid esterase-producing inoculant alone did not improve the nutritive value of alfalfa silage, and did not promote any incremental effects when applied in combination with fibrolytic enzyme products. Crown Copyright (C) 2014 Published by Elsevier B.V. All rights reserved.

Electrochemical studies based on local interfacial ph changes of gold nanoparticles immobilized on polystyrene brushes

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

Effect of initial pH in levan production by Zymomonas mobilis immobilized in sodium alginate

Zymomonas mobilis was immobilized using a cell suspension fixed to 8.6 x 10(7) CFU mL(-1) by spectrophotometry. This biomass was suspended in sodium alginate solution (3%) that was dropped with a hypodermic syringe into 0.2 M calcium chloride solution. Was test two initial pH of fermentation medium (4 and 5) and different sucrose concentrations 15, 20, 25, 30 and 35% at 30 degrees C, without stirring for 24, 48, 72 and 96 hours. The levan production to pH 4 was high in sucrose 25% for 24 (16.51 g L-1) and 48 (15.31 g L-1) hours. The best values obtained to pH 5 was in sucrose 35% during 48 (22.39 g L-1) and 96 (23.5 g L-1) hours, respectively. The maximum levan yield was 40.8% and 22.47% in sucrose 15% to pH 4 and 5, respectively. Substrate consumption to pH 4 was bigger in sucrose 15 (56.4%) and 20% (59.4%) and to pH 5 was in 25 (68.85%) and 35% (64.64%). In relation to immobilization efficiency, Zymomonas mobilis showed high adhesion and colonization in support, indicated by cell growth increased from 107 to 10(9) CFU mL(-1) during fermentation time.

INFLUENCE OF HVOF COATING ON THE FATIGUE STRENGTH OF 15-5 PH STAINLESS STEEL

Structural component failures due to cyclic loading are associated to surface damage of materials and its interaction with environment. Fatigue failure occurs with stresses below the yield strength of each material and is a result of crack initiation and propagation. In aeronautical components is an important parameter to be considered in project, as well as the corrosion and wear resistance. Thermally sprayed HVOF coatings have been considered to replace galvanic chromium deposits with comparable performance for wear and corrosion resistance. The aim of present research is to study the influence of WC-13Co-4Cr applied by HVOF, on the axial fatigue strength of 15-5 PH stainless steel. The shot peening treatment was used to restore fatigue performance.

In vitro fermentation parameters and biohydrogenation of vegetable oils without glycerol

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência da temperatura e do pH do meio sobre a resistência à corrosão das ligas Al(20204-T3), Al(7010-T7) e Al(7050-T7) utilizadas na indústria aeronáutica

Pós-graduação em Engenharia Mecânica - FEG

Avaliação do pH das secreções em hipofaringe, durante laparoscopia ginecológica: é seguro o emprego da máscara laríngea?

Pós-graduação em Anestesiologia - FMB

Milho ou polpa cítrica associados à glicerina na alimentação de bovinos de corte confinados

Pós-graduação em Zootecnia - FCAV

Glicerina associada à ureia na alimentação de bovinos Nelore

Pós-graduação em Zootecnia - FCAV

A utilização de glicerina em dietas para bovinos altera a microbiota ruminal

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

Efeito da suplementação de cloreto de amônio sobre os equilíbrios eletrolítico e ácido-básico e o pH urinário de ovinos confinados

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

Degradabilidade ruminal da matéria seca de grãos de milho e de sorgo com alto ou baixo conteúdo de tanino processados

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

Diversidade bacteriana ruminal em bovinos Nelore

Pós-graduação em Zootecnia - FCAV

Glicerina bruta associada a aditivos na alimentação de bovinos de corte

Pós-graduação em Zootecnia - FCAV