Cd phytoavailability in sewage sludge-amended soil of different pH estimated by an isotopic method and chemical extraction

The Cd phytoavailability in sewage sludge-amended soils of different pHs using the 109Cd L-value isotopic method and Cd extracted by DTPA has been determined. Maize plants (Zea mais L.) were grown under greenhouse conditions in a xanthic ferralsol at different pHs amended with five sewage sludge (SS) rates, and labeled with 74 kBq kg-1 of 109Cd. The SS rates altered the properties of the soil chemicals and these influenced the isotopic parameter (L-value) and percent of Cd uptake by plants from soil (%Cdpdfs) and SS (%CdpdfSS). L-values and Cd extracted by DTPA correlate significantly with SS rates and Cd uptake by plants and are efficient for predicting the Cd phytoavailability in the sewage sludge-amended soil.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

X-ray fluorescence technique applied to archaeological sample

The main objective of this study was the chemical determination of elements present in the sample (archaeological fragments), used the X-ray fluorescence techniques. Three analytical techniques were used: (i) conventional energy dispersive X-ray fluorescence (EDXRF), (ii) X-ray microfluorescence (μ-XRF) and (iii) scanning electronic microscopy coupled with energy dispersive X-ray fluorescence (SEM/ EDS). Starting from the chemical concentrations of the present elements in the samples of archaeological fragments, a clusters analysis was performed and with that a study of the identification of the ceramics origin.Com o intuito de se determinar a composição química elementar de amostras arqueológicas e de cerâmicas fabricadas, o presente trabalho utilizou as técnicas de fluorescência de raios X. Foram usadas três técnicas analíticas: (i) fluorescência de raios X dispersiva em energia (EDXRF) convencional, (ii) microfluorescência de raios X (μ-XRF) com fonte de luz Síncrotron e (iii) microscopia eletrônica de varredura acoplada com fluorescência de raios X dispersiva (SEM/EDS). A partir das concentrações químicas dos elementos presentes nas amostras de fragmentos arqueológicos, foi realizada uma análise de agrupamento e com isso um estudo de identificação de procedência das cerâmicas arqueológicas

Chemical changes and zinc phytoavailability in sewage sludge-amended soil estimated by the isotopic method

Zn availability in Red Latossol (Rhodic Ferralsol) of different pH amended with different rates of sewage sludge was studied by the isotopic 65Zn L value method. Soil chemical properties were found to be altered by SS addition. Zn concentration and Zn derived from SS (ZnpfSS) in plant, and Zn phytoavailability (L value), were increased with increasing SS rates. The linear correlation coefficient of plant Zn with SS rates and with L value was significant at 1% probability. The L value proved an efficient method for predicting Zn phytoavailability in sewage sludge-amended soil with different pH under the soil conditions studied

Paper-based diffusive gradients in thin films technique coupled to energy dispersive X-ray fluorescence spectrometry for the determination of labile Mn, Co, Ni, Cu, Zn and Pb in river water

The diffusive gradients in thin films (DGT) technique has shown enormous potential for labile metal monitoring in fresh water due to the preconcentration, time-integrated, matrix interference removal and speciation analytical features. In this work, the coupling of energy dispersive X-ray fluorescence (EDXRF) with paper-based DGT devices was evaluated for the direct determination of Mn, Co. Ni, Cu, Zn and Pb in fresh water. The DGT samplers were assembled with cellulose (Whatman 3 MM chromatography paper) as the diffusion layer and a cellulose phosphate ion exchange membrane (Whatman P 81 paper) as the binding agent. The diffusion coefficients of the analytes on 3 MM chromatography paper were calculated by deploying the DGT samplers in synthetic solutions containing 500 mu g L-1 of Mn. Co, Ni, Cu, Zn and Pb (4 L at pH 5.5 and ionic strength at 0.05 mol L-1). After retrieval, the DGT units were disassembled and the P81 papers were dried and analysed by EDXRF directly. The 3 MM chromatographic paper diffusion coefficients of the analytes ranged from 1.67 to 1.87 x 10(-6) cm(2) s(-1). The metal retention and phosphate group homogeneities on the P81 membrane was studied by a spot analysis with a diameter of 1 mm. The proposed approach (DGT-EDXRF coupling) was applied to determine the analytes at five sampling sites (48 h in situ deployment) on the Piracicaba river basin, and the results (labile fraction) were compared with 0.45 mu m dissolved fractions determined by synchrotron radiation-excited total reflection X-ray fluorescence (SR-TXRF). The limits of detection of DGT-EDXRF coupling for the analytes (from 7.5 to 26 mu g L-1) were similar to those obtained by the sensitive SR-TXRF technique (3.8 to 9.1 mu g L-1). (C) 2012 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Aplicação de fósforo para imobilização química do cádmio em solo contaminado Phosphorus application for the chemical immobilization of cadmium in contaminated soil

<abstract language="eng">The objective of the study was to evaluate the effect of phosphorus on the Cd availability to plants of a contaminated soil using 109Cd isotope and chemical extractants. The experiment was set in a randomized block design and the soil was labeled with 222 KBq of 109Cd per pot and received 5 rates of P as triple superphosphate, growing lettuce plants as test crop. The use of phosphorus reduced pH of soil which altered the Cd availability in DTPA and Mehlich extractants. The lettuce Cd content decreased but its accumulation and L value increased in all treatments compared to the control, demonstrating the inefficiency of phosphorus in reducing the Cd availability

Trânsito gastrintestinal e digestibilidade aparente de nutrientes em eqüinos alimentados com dietas contendo grãos secos ou silagem de grãos úmidos de triticale

Cinco éguas mestiças (idade e peso corporal médios de seis anos e 480 kg PV) foram distribuídas em delineamento experimental em quadrado latino para se e avaliar a utilização de dietas contendo grãos de triticale (secos ou ensilados) em substituição ao milho na alimentação de eqüinos, por meio do ensaio de avaliação do trânsito gastrintestinal e da digestibilidade. Os tratamentos consistiram de três níveis de grãos de triticale em substituição aos grãos de milho (0, 50 e 100%) e duas formas de conservação dos grãos de triticale (secos ou ensilados). As dietas foram isoprotéicas (12,5% PB), com ingestão diária de MS pelos animais de 2,0% PV (relação volumoso : concentrado de 50:50). Os coeficientes de digestibilidade aparente (CDa) da MS, MO, PB e FDN foram determinados indiretamente. Os parâmetros de trânsito gastrintestinal avaliados foram: k1 (taxa de passagem pelo intestino grosso), k2 (taxa de passagem pelo estômago), TT (tempo de trânsito), TMR (tempo médio de retenção) e TMRT (tempo médio de retenção total). Não houve diferença para os CDa da MS, MO, PB e FDN entre as dietas experimentais, observando-se valores médios de 64,31; 65,14; 74,13 e 57,25%, respectivamente. Considerando-se a cinética das fases sólida e líquida, notou-se efeito somente para k2 na fase sólida da digesta, cujo valor nas rações contendo 100% de triticale (seco ou ensilado) foi de 19,63%/h e na dieta controle (0% de triticale), de 23,72%/h. Observou-se efeito linear crescente para o TT na fase sólida da digesta, com a elevação dos níveis de substituição dos grãos de milho pelos grãos de triticale ensilados. Concluiu-se que os concentrados para eqüinos podem ser formulados com grãos de triticale secos ou ensilados em substituição total ao milho. A inclusão de grãos de triticale na alimentação desta espécie animal promoveu trânsito lento da fase sólida da digesta.Five crossbred mares (averaging six years and 480 kg BW) were allotted to latin square experimental design. The objective was to evaluate the utilization of diets containing triticale grains (dry or ensiled) in substitution of corn in the feeding of equine feeding, using assay of gastrointestinal transit and digestibility. The treatments consisted of three levels of triticale grains in substitution of corn grains (0, 50 and 100%), and two conservation forms of triticale grains (dry or ensiled). The diets were isoproteic (12.5% CP), with aDM intake by the animals of 2,0% BW (forage to concentrate 50:50). The apparent coefficients of digestibility (aCD) of the DM, OM, CP and NDF were determined by indirect method. The parameters of the gastrointestinal transit were: k1 (passage rate in the large intestine); k2 (passage rate in the stomach); TT (transit time); TMR (mean time retention) and TMRT (mean total retention time). No difference was observed for aCD of DM, OM, CP and NDF among the experimental diets, with means values of 64.31, 65.14, 74.13 and 57.25%, respectively. Considering the kinetics of the solid and liquid phases, it was found effect only to the k2 for the solid phase of digesta, whose values in the diets containing 100% triticale (dry or ensiled) was of 19.63%/h and the control diet of 23.72%/h. An increasing linear effect was observed for TT in the solid phase of digesta, as the levels of substitution of corn grain by ensiled triticale grain increased. In conclusion, the concentrates for equines may be formulated with dry or ensiled triticale grains in total substitution of corn grains. The inclusion of the triticale grains in the equine feeding promoted slow transit of the digesta

Nutritive value and kinetics study of digestive tract of diets to equine containing dry grains or high-moisture of sorghum grains silage of low and high tannin

Quatro éguas sem raça definida (idade e peso corporal médios de seis anos e 400 kg) foram distribuídas em delineamento experimental em quadrado latino para se avaliar o valor nutritivo e o estudo cinético do trato digestivo de grãos secos ou ensilados de sorgo de baixo e alto conteúdos de tanino na alimentação de eqüinos. Os tratamentos consistiram de dietas contendo dois híbridos de grãos de sorgo (baixo e alto níveis de tanino) e dois métodos de conservação (secos e ensilados). As dietas foram isoprotéicas (12,4% PB), com ingestão diária de MS estabelecida em 1,5% PV (relação feno:concentrado de 50: 50). Os parâmetros de trânsito gastrintestinal avaliados foram: k1 (taxa de passagem pelo intestino grosso), k2 (taxa de passagem pelo estômago), TT (tempo de trânsito), TMR (tempo médio de retenção) e TMRT (tempo médio de retenção total). Os tratamentos não afetaram os coeficientes de digestibilidade aparente (CDa) da MS e do amido, cujos valores médios foram 54,04 e 98,91%, respectivamente. Verificou-se efeito benéfico da ensilagem dos grãos de sorgo de alto conteúdo de tanino sobre a digestibilidade da PB e FDN. A CDa da PB e FDN para a dieta contendo grãos secos de sorgo de alto teor de tanino foi de 49,76 e 32,20% e para as dietas com grãos de sorgo de baixo conteúdo de tanino (seco ou ensilado) e grãos ensilados de sorgo de alto teor de tanino foi de 65,63 e 43,32%, respectivamente. Obteve-se somente efeito do método de conservação dos grãos de sorgo (secos vs ensilados) sobre o TMR, em que o valor para as dietas com silagens de grãos ensilados e secos foi, respectivamente, de 40,08 e 37,9h. Concluiu-se que os grãos de sorgo secos de alto teor de tanino não devem ser usados como principal grão energético nos concentrados para eqüinos, por diminuírem a digestibilidade da proteína e fibra.Four crosbred mares averaging six years and 400 kg BW were allotted to latin square design. The objective was to evaluate the nutritive values and kinetics of digestive tract of dry grains or high-moisture grains silage of sorghum with low and high tannin in the feeding of equines. The treatments consisted of diets containing two hybrids of sorghum grains (low and high tannin) and to methods of conservation (dry an ensiled). Diets were formulated to be isoprotein (12.4% CP) with daily DM intake established in 1.5% BW (hay to concentrate ratio of 50:50). The parameters of gastrointestinal transit were: k1 (passage rate in the large intestine); k2 (passage rate in the stomach); TT (transit time); MRT (mean retention time) and TMRT (mean total retention time). No effect treatment was observed for aCD of DM and starch, whose means values were 54.04 and 98.91%, respectively. A benefic effect of the ensiling of high tannin and high-moisture sorghum grains on digestibility of CP and NDF. The aCD of CP and NDF for diets containing high tannin and dry grains of sorghum was of 49.76% and 32.20% and for diets containing of low tannin sorghum grains (dry and ensiled) and high tannin and high-moisture sorghum grains was of 65.63 and 43.32%, respectively. There was effect only of the conservation method of the sorghum grains (dry versus ensiled) on the TMR, where the value for the diets with silages of high-moisture grains and dry grains was, respectively, of 40.08 and 37.9h. In conclusion, high tannin sorghum dry grains should not be used as the main grain in energetic concentrates for horses, because they reduced the digestion of protein and fiber

Determination of labile barium in petroleum-produced formation water using paper-based DGT samplers

A polyacrylamide hydrogel containing the Chelex-100 resin has traditionally been used as the binding agent for the diffusion gradients in thin films (DGT) technique. The Chelex-100 resin, although important for the determination of various transition metals, is unsatisfactory for the determination of alkaline earth metals, particularly Ba. In this paper, a cellulose membrane, treated with phosphate (P81 membrane), was evaluated as a binding agent for DGT devices for the determination of Ba in produced formation water (PEW) samples. In addition, diffusive layers of filter paper (cellulose) were tested to diffuse Ba through the DGT devices. Experiments to evaluate the key variables of the technique (pH, deployment time, and ionic strength/salinity) were performed. The Ba sampled by these DGT devices was measured using inductively coupled plasma optical emission spectrometry. Aiming to generate information (related to bioavailability of Ba) on the reuse of PEW for irrigation, the determination of Ba in onshore and offshore samples was performed. The new approach was effective for determination of Ba in onshore samples. To determine Ba in offshore samples, it was necessary to use an alternative calibration procedure due to the high NaCl concentration in these samples. (C) 2012 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq