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51.
Nogueira FG Castro IA Bastos AR Souza GA de Carvalho JG Oliveira LC 《Journal of hazardous materials》2011,186(2-3):1064-1069
The leather industry produces a large quantity of solid waste (wet blue leather), which contains a high amount of chromium. After its removal from wet blue leather, a solid collagenic material is recovered, containing high nitrogen levels, which can be used as a nitrogen source in agriculture. In order to take more advantage of the collagen, it was enriched with mineral P and K in order to produce NPK formulations. The objective was also to evaluate the efficiency of such formulations as a nutrient supply for rice plants in an Oxisoil, under greenhouse conditions. The application of PK enriched-collagen formulations resulted in N contents in the vegetative parts and grains of rice plants which were equivalent or superior to those obtained with urea and commercial NPK formulations. 相似文献
52.
Nogueira IR Carneiro G Yoshida MI de Oliveira RB Ferreira LA 《Drug development and industrial pharmacy》2011,37(9):1083-1089
Topical chemotherapy with paromomycin (PA) has been used as an alternative for the treatment of cutaneous leishmaniasis; however, poor skin penetration of this drug limits the efficacy of formulations. The objective of this work was to study the ability of the PA free base to form ion pairing with organic acids, as well as evaluate the effect of these compounds on the topical delivery of PA. PA permeation across intact skin was low, while drug penetration into skin from PA ion pairing was the higher than that observed for the PA base. Data obtained on the stripped skin, a damaged skin model, clearly showed that the ion pairing presented a potential to improve PA skin permeation. 相似文献
53.
Marafon AP Sumi A Granato D Alcântara MR Tamime AY Nogueira de Oliveira M 《Journal of dairy science》2011,94(11):5330-5340
This study aimed to evaluate the quality of stirred-type skim milk probiotic yogurt fortified by partially replacing skim milk powder (SMP) with whey protein concentrate (WPC) and sodium caseinate (Na-CN) during cold storage for 28 d compared with nonfortified yogurt. The rheological properties (as measured using dynamic oscillation) and sensory profiles of probiotic yogurts were greatly enhanced when SMP (i.e., 45%) was replaced with WPC and Na-CN. Higher values of mechanical parameters related to storage and loss modulus and consistent microstructure were found in the fortified yogurts. The acidification profile was not affected by supplementation of the solids in the milk base, and the viable counts of probiotic microbiota were high and satisfactory. These positive characteristics of probiotic yogurts were maintained until the end of the storage period. The microstructure of the fortified yogurt showed some differences compared with the nonfortified product, which were due to changes in chemical composition of the milk base in addition to the colloidal characteristics of the product. 相似文献
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55.
An accurate mapping of Internet traffic to applications can be important for a broad range of network management and measurement tasks, including traffic engineering, service differentiation, performance/failure monitoring and security. Traditional mapping approaches have become increasingly inaccurate because many applications use non-default or ephemeral port numbers, use well-known port numbers associated with other applications, change application signatures or use traffic encryption. In this paper we will demonstrate that multiscale traffic analysis based on multi-order wavelet spectrum can be used as a discriminator of Internet applications traffic profiles. By performing clustering analysis over the multiscale wavelet spectrum coefficients that are inferred from the measured traffic, the proposed methodology is able to efficiently differentiate different IP applications without using any payload information. This characteristic will allow the differentiation of traffic flows in unencrypted and encrypted scenarios. In order to compare the differentiating potential of different traffic application data, upload, download and joint upload and download flow statistics are considered to evaluate the identification approach for each selected protocol. Moreover, we also evaluate which timescales and spectrum orders are more relevant for the traffic differentiation. From the analysis of the obtained results we can conclude that the proposed methodology is able to achieve good identification results using a small set of timescales of a single order wavelet spectrum of a general raw traffic statistic. 相似文献
56.
Degradation of the antibiotic amoxicillin by photo-Fenton process--chemical and toxicological assessment 总被引:1,自引:0,他引:1
The influence of iron species on amoxicillin (AMX) degradation, intermediate products generated and toxicity during the photo-Fenton process using a solar simulator were evaluated in this work. The AMX degradation was favored in the presence of the potassium ferrioxalate complex (FeOx) when compared to FeSO4. Total oxidation of AMX in the presence of FeOx was obtained after 5 min, while 15 min were necessary using FeSO4. The results obtained with Daphnia magna biossays showed that the toxicity decreased from 65 to 5% after 90 min of irradiation in the presence of FeSO4. However, it increased again to a maximum of 100% after 150 min, what indicates the generation of more toxic intermediates than AMX, reaching 45% after 240 min. However, using FeOx, the inhibition of mobility varied between 100 and 70% during treatment, probably due to the presence of oxalate, which is toxic to the neonates. After 240 min, between 73 and 81% TOC removal was observed. Different pathways of AMX degradation were suggested including the opening of the four-membered β-lactamic ring and further oxidations of the methyl group to aldehyde and/or hydroxylation of the benzoic ring, generating other intermediates after bound cleavage between different atoms and further oxidation to carboxylates such acetate, oxalate and propionate, besides the generation of nitrate and ammonium. 相似文献
57.
58.
JJ Reina Zoilo M Ruiz Borrego JC Valenzuela Claros MJ Valladares Ayerbes P Borrega García A Viana Alonso JA Moreno Nogueira 《Canadian Metallurgical Quarterly》1998,15(2):97-99
Photosensitive epilepsy is relatively rare. However, a large proportion of individuals with epilepsy perceive that they are at an increased risk of a seizure whilst exposed to specific photic material. The difference between perceived and real risk may be due to inadequate education and misinformation. One half of the participants in the present survey could not recall being informed of the result of the 'gold standard' test for photosensitivity--intermittent photic stimulation during an electroencephalogram. Furthermore, approximately one-third of our sample were apparently given inaccurate and overcautious advice about their everyday exposure to photic material. Better information and advice is crucial to improve this situation in the future. The majority of people with epilepsy (>95%) who are not photosensitive can pursue activities that involve flickering or patterned light, encompassing educational, employment and leisure opportunities, without undue concern. 相似文献
59.
Evaluation of the combined solar TiO2/photo-Fenton process using multivariate analysis. 总被引:1,自引:0,他引:1
The effect of combining the photocatalytic processes using TiO2 and the photo-Fenton reaction with Fe3+ or ferrioxalate as a source of Fe2+ was investigated in the degradation of 4-chlorophenol (4CP) and dichloroacetic acid (DCA) using solar irradiation. Multivariate analysis was used to evaluate the role of three variables: iron, H2O2 and TiO2 concentrations. The results show that TiO2 plays a minor role when compared to iron and H2O2 in the solar degradation of 4CP and DCA in the studied conditions. However, its presence can improve TOC removal when H2O2 is totally consumed. Iron and peroxide play major roles, especially when Fe(NO3)3 is used in the degradation of 4CP. No significant synergistic effect was observed by the addition of TiO2 in this process. On the other hand, synergistic effects were observed between FeOx and TiO2 and between H2O2 and TiO2 in the degradation of DCA. 相似文献
60.
A study was carried out from 23 October to 19 November 1992 to determine the ability of fish to ascend the fish ladder at the ITAIPU dam, to identify the species attracted and to evaluate possible fish selection. The results show that some species of fish can ascend the ladder during the migratory period; the dam is non-selective with respect to species, but selective with respect to fish size as a result of the presence of reduced openings. The ladder was ascended by both scaly species from surface waters (agile movers) and by deep water species which were characterized by slow movements. An average of 2892 fish ascended the ladder each day. The weight and length of fish recorded ranged from 336.0 to 3676.0 g and from 30.2 to 71.3 cm, respectively. The largest group of migrating fish was the curimba (Prochilodus scrofa). The high ratio of 72% of fish in the gonadal development stage, classified as ‘maturing’, indicates that the species caught in the ladder were migrating for reproduction purposes. 相似文献