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121.
Removal of Arsenic from Aqueous Solutions by Sorption onto Sewage Sludge-Based Sorbent 总被引:1,自引:0,他引:1
Daniela S. Tavares Cláudia B. Lopes Jo?o P. Coelho Marta E. Sánchez Ana I. Garcia Armando C. Duarte Marta Otero Eduarda Pereira 《Water, air, and soil pollution》2012,223(5):2311-2321
This study aimed at evaluating and comparing the removal of arsenic from solutions by a low-cost waste-based sorbent, produced by pyrolysing sewage sludge under appropriate conditions, and by a commercially activated carbon. Batch sorption experiments were performed under isothermal conditions (20°C), in order to evaluate the effect of pH on the arsenic sorption kinetics and on the equilibrium sorption capacity of the materials under study. Kinetic data revealed that the arsenic sorption was faster onto the activated carbon than onto the pyrolysed sludge. The sorption process was well described by both the pseudo-first and pseudo-second-order kinetics equations for both materials. Changes in the initial solution pH have distinct effects on the removal of arsenic onto pyrolysed sludge and activated carbon. While for pyrolysed sludge, pH affects essentially the equilibrium time, for activated carbon it affects the sorption capacity. Equilibrium results were well described by both Freundlich and Langmuir isotherm models, although fittings corresponding to the Langmuir isotherm were slightly better. The Langmuir maximum sorption capacity determined for the pyrolysed sludge was 71???g?g?1, while for activated carbon was 229???g?g?1. Despite the relative lower capacity of the pyrolysed sludge, the considerable lower cost and the valorisation of the sludge may justify further research on its use for water decontamination. 相似文献
122.
Daniela Gargano Nunzia Scotti Alessandro Vezzi Alessandra Bilardi Giorgio Valle Stefania Grillo Salvatore Cozzolino Teodoro Cardi 《Genetic Resources and Crop Evolution》2012,59(3):419-430
The plastome sequence of the European cultivated potato, Solanum tuberosum subsp. tuberosum (tbr, GenBank accession no. DQ386163), was compared with that of S. bulbocastanum, a wild potato relative (blb, GenBank accession no. DQ347958), in order to characterize the degree and type of variability
in different genomic regions, and develop molecular markers relevant to genetics, breeding and biotechnology of potato. One
hundred forty-two and 251 PICs (Potentially Informative Characters) were found in coding and non-coding sequences (NCSs),
respectively. Further, while variation in coding regions was almost exclusively due to nucleotide substitutions, 25% of PICs
in NCSs of tbr and blb were due to indels, most of them mononucleotide or longer tandem repeats (micro and minisatellites).
Four intergenic regions were selected for further analyses in other 16 tuber-bearing Solanum species. The rps16-trnQ
UUG
gene spacer was found to be the most variable, forty-six PICs in this region distinguishing 18 haplotypes. Analysis of haplotype
relationships, based on variability in the four intergenic regions, confirmed that the most primitive species from Central
America were the most distant to S. tuberosum. Finally, polymorphic sites in the same regions were used to develop a set of CAPS (Cleaved Amplified Polymorphic Sequences)
markers for species/cytoplasm identification in Solanum spp. 相似文献
123.
Marcelo Pedrosa Gomes Daniela Moreira Duarte Pedro Luiz Silva Miranda Leilane Carvalho Barreto Miele Tallon Matheus Queila Souza Garcia 《植物养料与土壤学杂志》2012,175(3):466-473
Anadenanthera peregrina is a Brazilian savanna tree species that occurs naturally in arsenic (As)‐contaminated areas, and its As resistance has been associated with arbuscular mycorrhizal–fungi (AMF) symbiosis. A plant's ability to survive in stressful environments is correlated with its nutrition status, which can be affected by As uptake. The present study evaluated the influence of As on the concentrations and distribution of nutrients in the roots and shoots of A. peregrina grown in the absence of AMF. These plants were grown in substrates spiked with 0, 10, 50, and 100 mg As kg–1 for 25 d under greenhouse conditions, and the concentrations of essential macro‐ (P, K, Ca, Mg, N, and S) and micro‐ (Fe, Mn, Cu, Zn, B, and Mo) nutrients in the roots and shoots were then determined. Enhanced As levels increased the concentrations of P, S, and N and decreased Ca, Mg, and Fe. Although the deleterious effects of As on the plants were striking, the internal As levels were high, which indicated some tissue tolerance of A. peregrina. 相似文献
124.
Spada E Proverbio D Groppetti D Perego R Grieco V Ferro E 《Journal of the American Animal Hospital Association》2011,47(1):67-71
Canine leishmaniasis during pregnancy is rarely reported, even in countries where the infection in dogs is endemic. The authors report a case of a 4 yr old bitch with leishmaniasis treated with meglumine antimoniate during pregnancy. The pregnancy and delivery were normal and the bitch presented improvement of the infection during treatment. Three puppies died within 2 days of birth and tested negative via real-time PCR for L. infantum. The two surviving puppies were followed clinically, serologically, and by real-time PCR until 1 yr of age with no evidence of congenital leishmaniasis. L. infantum DNA was detected with real-time PCR analysis of uterine tissue from the bitch at the time of ovariohysterectomy. PCR analysis was performed after an ovariohysterectomy of the bitch that was performed two months after parturition. Meglumine antimoniate use in the pregnant bitch may have prevented vertical transmission of leishmaniasis. 相似文献
125.
Bellato S Del Frate V Redaelli R Sgrulletta D Bucci R Magrì AD Marini F 《Journal of agricultural and food chemistry》2011,59(9):4349-4360
A rapid accurate and precise method for simultaneous determination of β-glucan and protein content in naked oat samples, based on the coupling of near-infrared spectroscopy and chemometrics, is presented. In particular, three different spectroscopic approaches [near infrared reflectance (NIR) and transmittance (NIT) on flour and NIT on whole grains] and various spectral pretreatments were considered. To account for the possibility of outlying samples, a robust version of the PLS algorithm (namely partial robust M-regression) was used. All the models resulted as accurate as the reference methods, reflectance spectroscopy being the technique providing the best outcomes. Variable reduction by inclusion of the most relevant predictors only (as evaluated by VIP scores) resulted in simpler and, in one case, more parsimonious models, without loss in accuracy. 相似文献
126.
Harald Ficker Hubert Gassner Daniela Achleitner Robert Schabetsberger 《Water, air, and soil pollution》2011,218(1-4):109-120
Lake Hallstättersee is a holomictic alpine lake, which is influenced by salt mining since the middle Bronze Age. Beside the constant saline waste water load, two massive brine spills loaded the lake with additional 16,900 tons sodium chloride (??10,250 tons Cl?) from 1977 to 1979 and 3,000 tons salt (??1,820 tons Cl?) in 2005. The effect of waste water intrusions from salt mining on stratification of Lake Hallstättersee was analysed over a period of 40 years. Water density, dissolved oxygen and total phosphorus (TP) concentrations were measured and an exponential model was fitted to describe the wash-out of chloride from Lake Hallstättersee after the brine spills. Furthermore, the time required returning to holomixis and steady chloride content after the second brine spill was estimated. During the whole sampling period the minimum and maximum volume-weighted annual mean chloride concentrations were 23.58 mg/L in 1979 and 3.19 mg/L in 1998. However, the mixing regime of Lake Hallstättersee, as well as the chloride concentrations, varied considerably and exhibited three holomictic and three meromictic periods between 1970 and 2009. Holomictic periods were observed when the yearly density gradient was below 0.06 kg/m3, deepwater oxygen in spring above 4 mg/L and consequently declining TP concentration in the deepest water layer below 60 mg/m3, otherwise meromictic periods were observed. Our study showed that Hallstättersee was 13 years ectogenic meromictic and 27 years holomictic during the study period. 相似文献
127.
128.
Barbosa Douglas Rafael e Silva dos Santos Rebeca Barbosa Vieira Santos Flavia Mayara Pereira da Silva Junior Pedro Justino de Oliveira Neto Francisco Marques Silva Gutierres Nelson de Andrade Dutra Kamilla do Amaral Ferraz Navarro Daniela Maria 《植物病害和植物保护杂志》2022,129(1):125-136
Journal of Plant Diseases and Protection - This study aimed to investigate the effects of the essential oils of Cymbopogon flexuosus and Alpinia zerumbet in the treatment of cowpea [Vigna... 相似文献
129.
130.
Perazzini R Leonardi D Ruggeri S Alesiani D D'Arcangelo G Canini A 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):211-218
Eight Phaseolus vulgaris L. landraces cultivated on farm in marginal areas of Central Italy (Lazio region) were investigated in order to evaluate
chemical composition of storage proteins and secondary metabolites fractions. The total protein content showed some differences
among landraces; the maximum value was next to 30 g for 100 g of dry weight. The seed storage proteins were screened by polyacrylamide
gel electrophoresis (SDS/PAGE): seven landraces exhibited phaseolin patterns type S, one landrace showed a phaseolin pattern
type T. A morphological analysis of cotyledon parenchyma performed by scanning electron microscopy (SEM) revealed differences
in size of starch granules. Moreover the polyphenolic composition was investigated using HPLC-APCI; from the methanol extracts
a flavonoid, kaempferol, and a coumarin, 5,7-dimethoxycoumarin, were identified. To our knowledge, this is the first time
that 5,7-dimethoxycoumarin has been reported in P. vulgaris seeds. 相似文献