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111.
The petroleum industry stands out for causing significant environmental risks from contamination of the air, water and soil. The removal of organic pollutants from the environment poses a great technological challenge, making it increasingly necessary to develop efficient clean-up technologies. Surfactant solutions have been used to remediate soils and aquifers contaminated by hydrocarbons or crude oil derivatives. The aim of this study was to develop nanoemulsions and analyze their efficiency in extracting crude oil from a sand sample. The nanoemulsions were prepared by the phase inversion temperature (PIT) method. The oil phase consisted of orange oil and the nonionic surfactant ethoxylated lauryl ether (Ultrol L70) was used to stabilize the nanoemulsions. The surfactant concentrations were varied from 10 to 12 wt% and the oil phase from 5 to 20 wt%. The efficiency of extraction of oil from sand was assessed using the two nanoemulsions that presented the greatest stability (containing 5 wt% oil phase with 12 wt% surfactant and 20 wt% oil phase with 10 wt% surfactant). A 2(3) factorial experimental design with center point was used to evaluate and improve the soil washing process, varying the time, temperature and agitation speed of the system. The highest efficiencies were obtained at 45 degrees C. 相似文献
112.
Luciana Gaffo Márcia R. Cordeiro Adonilson R. Freitas Wania C. Moreira Emerson M. Girotto Valtencir Zucolotto 《Journal of Materials Science》2010,45(5):1366-1370
Phthalocyanine compounds have been widely investigated as candidate materials for technological applications, which is mainly
due to their thermal stability and possibility of processing in the form of thin films. In most applications, the controlled
growth of thin films with high crystalline quality is essential. In this study, zinc phthalocyanine (ZnPc) thin films were
prepared by evaporation on glass and Au-coated glass substrates with subsequent annealing at different temperatures in ambient
atmosphere. The morphological and structural features of 80 nm thick zinc phthalocyanine films were investigated, evidencing
an α → β phase transformation after annealing the films at 200 °C, as indicated by UV–Vis spectroscopy and FTIR analyses.
A better uniformity of the annealed films was also evidenced via AFM analysis, which may be of importance for applications
where film homogeneity and excellent optical quality are required. 相似文献
113.
Luciana Lazzeretti Niccolò Innocenti Francesco Capone 《The Annals of Regional Science》2017,58(3):491-512
Cultural and creative industries (CCIs) have recently become highly relevant with regard to creative economy research, as they are considered drivers of regional and urban innovation policies and economic growth. CCIs are a priority sector on the European agenda and represent an excellent opportunity to exit the current economic crisis. In the literature, the most discussed aspect of CCIs is their value creation ability, which is due to a high degree of diversity/variety, and their impact on innovation within the wider economy, which results from the activation of cross-fertilisation processes between different sectors. Evolutionary economic geography (EEG), adopting the recently established approach based on related variety, also emphasises the issues of diversity/variety as determinants of local and urban development and innovation. This interesting and complex theoretical framework has produced a considerable number of empirical studies, none of which has been specifically applied to the creative sector. With the present study, we intended to contribute to the debate on creative economy research and EEG by investigating the impact of variety in CCIs in Italy, following the related-variety approach and using a long-term employment perspective (1991–2011). The results indicated that related variety has an important effect on the growth of creative industries, characterised by high internal connections between different creative activities. Our outcomes also led us to reassess the view held by some, namely, that creative industries can actually make a strong impact on economic growth in the wider economy; this did not appear to emerge in the Italian context, according to the methodologies we used. 相似文献
114.
Annurca (Malus pumila Miller cv. Annurca) apple as a functional food for the contribution to a healthy balance of plasma cholesterol levels: results of a randomized clinical trial
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115.
Alejandra P. Magnoli Luciana Tallone Carlos A.R. Rosa Ana M. Dalcero Stella M. Chiacchiera Rosa M. Torres Sanchez 《Applied Clay Science》2008,40(1-4):63-71
Some bentonites have been probed to be efficient as sequestering agents for aflatoxins; they decreased the bioavailability of the toxin in the gastrointestinal tracts of birds when they are incorporated in the diets. The binding capacity of these adsorbents varied with the rheological source and even among batches of a given source. Three bentonites from different sources in Argentina, which have very different aflatoxins (AFs) adsorption capacity, were studied. The characterization comprises chemical analysis, scanning electron microscopy (SEM), X-ray power diffraction (XRD), Hg intrusion porosimetry, swelling capacity, etc. The main factors affecting the adsorption of AFs seem to be related to the isomorphic substitution of the montmorillonite and to electrostatic interactions generated by the surface charge of the samples. Neither the mean pore size nor the percentage of quartz has any effect upon the AFs adsorption. 相似文献
116.
L Tamborini A Pinto TK Smith LL Major MC Iannuzzi S Cosconati L Marinelli E Novellino L Lo Presti PE Wong MP Barrett C De Micheli P Conti 《ChemMedChem》2012,7(9):1623-1634
Acivicin analogues with an increased affinity for CTP synthetase (CTPS) were designed as potential new trypanocidal agents. The inhibitory activity against CTPS can be improved by increasing molecular complexity, by inserting groups able to establish additional interactions with the binding pocket of the enzyme. This strategy has been pursued with the synthesis of α‐amino‐substituted analogues of Acivicin and N1‐substituted pyrazoline derivatives. In general, there is direct correlation between the enzymatic activity and the in vitro anti‐trypanosomal efficacy of the derivatives studied here. However, this cannot be taken as a general rule, as other important factors may play a role, notably the ability of uptake/diffusion of the molecules into the trypanosomes. 相似文献
117.
Pfannkuchen M Godrijan J Pfannkuchen DM Iveša L Kružić P Ciminiello P Dell'Aversano C Dello Iacovo E Fattorusso E Forino M Tartaglione L Godrijan M 《Environmental science & technology》2012,46(10):5574-5582
Mass appearances of the toxic dinoflagellate genus Ostreopsis are known to cause dangerous respiratory symptoms in humans exposed to aerosols. The outbreaks can appear in shallow marine waters of temperate regions around the globe. We followed a massive bloom event on a public beach on the northern Adriatic coast near Rovinj, Croatia. We identified the responsible species and the produced toxins as well as the dynamics of the event with respect to environmental conditions. Ostreopsis cf. ovata appeared in masses from September through October 2010 on a public beach near Rovinj, Croatia but stayed undetected by public health organizations. Respiratory symptoms were observed whenever humans were exposed to substrate samples containing large numbers of Ostreopsis cells. During the mass abundance of O. cf. ovata also exposure to the aerosols on the beach evoked respiratory symptoms in humans. Our measurements showed high cell abundances and high toxin contents with a stable relative contribution of putative Palytoxin and Ovatoxins a-e. Artificial beach structures proved to dramatically reduce settling of the observed Ostreopsis biofilm. Blooms like those reported herein have a high potential to happen undetected with a high potential of affecting the health of coastal human populations. Increased monitoring efforts are therefore required to understand the ecology and toxicology of those bloom events and reduce their negative impact on coastal populations. 相似文献
118.
Juliana Moraes Souza Araújo Airla Carla Pires de Siqueira Arie Fitzgerald Blank Narendra Narain Luciana Cristina Lins de Aquino Santana 《Food and Bioprocess Technology》2018,11(9):1750-1760
The effect of edible cassava starch–chitosan coatings incorporated with rosemary pepper (Lippia sidoides Cham.) essential oil and pomegranate peel extract on the shelf-life of tomatoes during storage at 25 °C for 12 days was investigated. Sixteen formulations, containing 10 g L?1 cassava starch and various concentrations of chitosan (5, 10, 20, 30 g L?1), essential oil (0, 2.5, 5, 10 mL L?1) and pomegranate peel extract (0, 5, 10, 20 mL L?1) were prepared and applied to tomatoes. Physical–chemical and microbiological analyses were performed on days 1, 4, 8 and 12. Most of the coatings delayed the ripening of tomatoes, lowering the total soluble solids (38?44 g sucrose kg?1) and weight loss (93?128 g kg?1) and maintaining constant firmness compared to the uncoated tomatoes (45 g sucrose kg?1, 175 g kg?1) at 12 days of storage. Conversely, except red intensity (a*), which was higher for the uncoated samples, the colour parameters (L*, b*) of the coated and control tomatoes were similar at the end of storage. Uncoated and coated tomatoes showed no contamination during storage. The coatings showed potential to maintain the quality of tomatoes during storage at 25 °C for 12 days. In this context, tomatoes coated with the formulation comprising 10 g L?1 cassava starch, 10 g L?1 chitosan, 10 mL L?1 essential oil and 20 mL L?1 pomegranate peel extract showed the lowest weight loss and reduced total soluble solids content compared with uncoated ones. 相似文献
119.
M. Luciana Villaverde M. Patricia Jurez Sergio Mijailovsky 《Journal of Stored Products Research》2007,43(4):540-545
The solid phase microextraction (SPME) technique was used for the collection of the volatile defensive secretions released by Tribolium castaneum (Herbst), the red flour beetle. The detection of the major components methyl-1,4-benzoquinone (MBQ) and ethyl-1,4-benzoquinone (EBQ), together with 1-pentadecene (C15:1), was performed by capillary gas chromatography (CGC). SPME samples were identified by CGC coupled to mass spectrometry (MS). Volatile organic compounds (VOC) released from insects were compared employing different SPME fibers. The relative amounts of the major volatiles collected varied with the fiber coating. Quinones accounted for 75% of the volatiles trapped by the carboxen/polydimethylsiloxane (CAR/PDMS) fiber, whereas they only represented 45% of the volatiles trapped with the PDMS fiber. The PDMS/divinylbenzene (DVB) coating exhibited intermediate affinity. In a 15-min extraction period, the highest amounts of VOC extracted from disturbed insects with CAR/PDMS were 349±107 ng/beetle of MBQ, 780±290 ng/beetle of EBQ, and 144±69 ng/beetle of C15:1. The total VOC amounts extracted by SPME were estimated by adding the disturb-released VOC to heat-released VOC of the same insects, resulting in 742±93 ng/beetle of MBQ, 1672±244 ng/beetle of EBQ, and 946±237 ng/beetle of C15:1. SPME-CGC is a simple method to detect and estimate T. castaneum volatiles. This method has the potential to detect insect infestation in stored products. 相似文献
120.
Lombardi A Maistro LD De Dea P Gatti M Giraffa G Neviani E 《The Journal of dairy research》2002,69(1):139-149
In the present work, 67 strains of Lactobacillus helveticus isolated from whey starter cultures and cheeses were identified and grouped by genotypic and phenotypic methods. Strains were identified by sugar fermentation pattern, by cell-wall protein profile, and by probe hybridisation. Phenotypic diversity was evaluated by a chemometric model taking into account biochemical characteristics (i.e. acidifying and peptidase activities) of technological interest. Genotypic diversity was evidenced by RAPD-PCR, which provided stran-specific patterns and revealed the occurrence of different strains. The RAPD-PCR profiles were clustered according to their similarities: the groups obtained, together with the cell-wall protein profiling and the chemometric information, could be sometimes correlated with the type of cheese and/or dairy niches used as sources of strains. A computerised analysis of genotypic and phenotypic information could be successfully applied for rapid and reliable differentiation and characterisation of Lb. helveticus isolates occurring in different dairy products. 相似文献