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91.
Marsaro AL Souza RC Della Lucia TM Fernandes JB Silva MF Vieira PC 《Journal of chemical ecology》2004,30(9):1771-1780
The response of Atta sexdens rubropilosa Forel workers to essential oils, epicuticular wax and hexane, dichloromethane, ethyl acetate, and methanol extracts of Eucalyptus maculata was evaluated. Hexane extracts of E. maculata interfered with the recognition mechanism among workers. The main active compounds identified from this plant were the sesquiterpenes elemol and beta-eudesmol. These compounds may be responsible for the resistance of this species to ant attack. 相似文献
92.
Catalysts based in cerium oxide for wet oxidation of acrylic acid in the prevention of environmental risks 总被引:3,自引:0,他引:3
Adrin M. T. Silva Rita R. N. Marques Rosa M. Quinta-Ferreira 《Applied catalysis. B, Environmental》2004,47(4):269-279
Acrylic acid is a refractory compound for the non-catalytic wet oxidation (WO) process and can seriously damage the environment when released in industrial effluents. Oxidation of acrylic acid by catalytic wet oxidation (CWO) was studied in slurry conditions in a high-pressure batch reactor at 200 °C and 15 bar of oxygen partial pressure. Several solid cerium-based catalysts prepared in our laboratory were used (Ag/Ce, Co/Ce, Mn/Ce, CeO, MnO) and evaluated in terms of activity, selectivity and stability. Mn/Ce shows the higher activity in 2 h with 97.7% reduction of total organic carbon (TOC) followed by: MnO(95.5%)>Ag/Ce(85.0%)>Co/Ce(65.1%)>CeO(61.2%). Attempts were also carried out to analyze the influence of different Mn/Ce molar ratios. High percentages of Mn lead to practically total organic carbon concentration (TOC) abatements while low ratios lead to the formation of non-oxidizable compounds. Acrylic acid was readily degraded by all the catalysts pointing out the high importance of using a catalytic process. pH was an indicator of the reaction pathway and acetic acid was found as the major reaction intermediate compound; however it is completely oxidized after 2 h with exception for Co/Ce, CeO and MnO. Carbon adsorption and leaching of metals were poorly found for Mn/Ce indicating high stability. The catalyst microstructure after the reaction was analyzed and formation of whiskers of β-MnO2 (or less probably MnOOH) were observed at the catalyst surface. Therefore, Mn/Ce revealed to be a promising catalyst for the treatment of effluents containing acrylic acid; nevertheless, its commercialization depends on further research. 相似文献
93.
Guimes Rodrigues Filho Leandra Cardoso Toledo Daniel Alves Cerqueira Rosana Maria Nascimento de Assunção Carla da Silva Meireles Harumi Otaguro Sizue Ota Rogero Ademar Benévolo Lugão 《Polymer Bulletin》2007,59(1):73-81
Summary In this article, cellulose acetate produced through the homogeneous acetylation of sugar cane bagasse cellulose was used to
produce membranes, using poly(ethyleneglycol) 600 (PEG 600) as an admixture. The membranes were characterized using water
flux measurements (Payne’s cup), differential scanning calorimetry (DSC) and neutral red uptake (cytotoxicity). The results
showed that PEG 600 acts as a crystallinity inductor and/or pore former in the cellulose acetate matrix. The induction of
crystallinity is important for this system since it had not been reported on the literature yet. The results also demonstrated
that the studied membranes present a nontoxic behavior. 相似文献
94.
Jean‐Rémy Falleri Xavier Blanc Reda Bendraou Marcos Aurélio Almeida da Silva Cédric Teyton 《Software》2014,44(5):621-641
Ensuring models’ consistency is a key concern when using a model‐based development approach. Therefore, model inconsistency detection has received significant attention over the last years. To be useful, inconsistency detection has to be sound, efficient, and scalable. Incremental detection is one way to achieve efficiency in the presence of large models. In most of the existing approaches, incrementalization is carried out at the expense of the memory consumption that becomes proportional to the model size and the number of consistency rules. In this paper, we propose a new incremental inconsistency detection approach that only consumes a small and model size‐independent amount of memory. It will therefore scale better to projects using large models and many consistency rules. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
95.
André Lourenço Hugo Plácido da Silva Carlos Carreiras Ana Priscila Alves Ana L. N. Fred 《Multimedia Tools and Applications》2014,70(1):433-460
With the advent of wearable sensing and mobile technologies, biosignals have seen an increasingly growing number of application areas, leading to the collection of large volumes of data. One of the difficulties in dealing with these data sets, and in the development of automated machine learning systems which use them as input, is the lack of reliable ground truth information. In this paper we present a new web-based platform for visualization, retrieval and annotation of biosignals by non-technical users, aimed at improving the process of ground truth collection for biomedical applications. Moreover, a novel extendable and scalable data representation model and persistency framework is presented. The results of the experimental evaluation with possible users has further confirmed the potential of the presented framework. 相似文献
96.
G. L. Chen C. Guyon Z. X. Zhang B. Da Silva P. Da Costa S. Ognier D. Bonn M. Tatoulian 《Microfluidics and nanofluidics》2014,16(1-2):141-148
In this paper, tricobalt tetraoxide (Co3O4) catalyst was coated on the polydimethylsiloxane microchannel by the plasma-enhanced metal-organic chemical vapor deposition technology. The obtained Co3O4 film was characterized by SEM, XRD, XPS, and TEM, and the results show that the as-deposited Co3O4 film was initially composed of many cauliflowers-shaped microclusters. Also, the microcauliflower was transformed from an amorphous phase to a crystal phase when the Co3O4 film was treated by Ar and O2 plasma for more than 20 min, and the crystal lattice line occurred on the surface of nano-sized-Co3O4 particles. Meanwhile, the interface of Co3O4 particles with diameter between 3 and 12 nm became obvious and some nano-catkin structures were also formed on the Co3O4 film. The ratio of Co3+/Co2+ in the spinel-type Co3O4 was nearly 2, and the nano-particles predominantly expose their {311}, {111}, and {220} planes. These morphologies and structure characteristics were found to be ideal for increasing the catalytic activity efficiency of Co3O4 for CO oxidation, and the catalytic stability of Co3O4 coated on the organic microreactor lasted nearly 85 h for trace CO oxidation at room temperature. 相似文献
97.
A. Takezawa M. Kitamura S.L. Vatanabe E. C. N. Silva 《Structural and Multidisciplinary Optimization》2014,49(2):281-297
This paper describes a design methodology for piezoelectric energy harvesters that thinly encapsulate the mechanical devices and exploit resonances from higher-order vibrational modes. The direction of polarization determines the sign of the piezoelectric tensor to avoid cancellations of electric fields from opposite polarizations in the same circuit. The resultant modified equations of state are solved by finite element method (FEM). Combining this method with the solid isotropic material with penalization (SIMP) method for piezoelectric material, we have developed an optimization methodology that optimizes the piezoelectric material layout and polarization direction. Updating the density function of the SIMP method is performed based on sensitivity analysis, the sequential linear programming on the early stage of the optimization, and the phase field method on the latter stage of the optimization to obtain clear optimal shapes without intermediate density. Numerical examples are provided that illustrate the validity and utility of the proposed method. 相似文献
98.
Julio Cesar dos Reis Rodrigo Bonacin M. Cecília C. Baranauskas 《Universal Access in the Information Society》2014,13(2):125-145
Social network services (SNSs) have brought new possibilities and challenges to the design of software environments that respect people’s cultural differences. These systems may represent an opportunity for social and digital inclusion. However, search mechanisms in these systems impose serious barriers for people in the process of acquiring digital literacy. One of the barriers is the difficulty of using the adequate terms/keywords to perform content searches. This paper presents an approach to allow ordinary, non-technology proficient people to access the content of a network through the use of search parameters that make sense to them. The proposal is grounded on Semantic Web technologies (Web ontology) combined with Organizational Semiotics concepts and methods to identify the users’ profile and language. A case study was conducted with the search mechanism integrated into a SNS, and a preliminary evaluation reveals the advantages and drawbacks of the approach. 相似文献
99.
Renan Felicio dos Reis Joao Sergio Cordeiro Xavier Font Cali Laguna Achon 《Drying Technology》2020,38(10):1247-1260
AbstractSewage treatment can be classified into three phases: liquid, gaseous, and solid. Treatment of solids is performed in several steps, and the greatest difficulty in removing water from sewage sludge is due to the bound water present in the sludge. Thus, biodrying, a drying method that can be classified as biological, has been recently applied to treat this type of waste. This review paper aims to report and compile data from 49 biodrying assays of sewage sludge found in the literature (through the present, 2019) into one synthesis table, to discuss and compare the numerous variables found in these papers and their implications for biodrying, and to suggest possibilities for future research. This paper additionally intends to improve knowledge of biodrying and to consequently contribute to the monitoring and understanding of the process. 相似文献
100.
Luis Carlos da Silva Ramos Joao Shogiro Tango Angelo Savi Nilson Roberto Leal 《Journal of the American Oil Chemists' Society》1984,61(12):1841-1843
Thirty-six castorbean varieties were surveyed for oil and fatty acid composition, in order to determine variability of these
seed compounds. A large variability of seed oil percentage was observed, ranging from 39.6 to 59.5%. Concerning the fatty
acids, little variability was observed for ricinoleic acid, which was the most abundant in the oil, ranging from 83.65 to
90.00%. The other fatty acids appeared in small concentrations and showed a small range: 0.87 to 2.35, 0.68 to 1.84, 2.96
to 5.64, 3.19 to 5.98, and 0.34 to 0.91%, for palmitic, stearic, oleic, linoleic, and linolenic acid, respectively. Non-significant
correlations were observed between fatty acids and seed oil percentage. However, significant correlations were observed among
fatty acid concentrations: positive and negative ones. These significant correlations could be associated with the biosynthetic
pathways of the fatty acids, which are not fully elucidated. They suggest, however, that selection for a particular fatty
acid will tend to increase those positively correlated, and decrease those negative ones. Selection and plant breeding techniques
could then be applied to modify the oil content of the castorbean seeds, considering the variability observed. For the fatty
acid composition, however, the variability was not large enough to make substantial changes in their concentrations by selection
procedures. More varieties should be surveyed to find out if such variability is available. 相似文献