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91.
In this study, the destruction rate of a volatile waste destruction system based on a microwave plasma torch operating at atmospheric pressure was investigated. Atmospheric air was used to maintain the plasma and was introduced by a compressor, which resulted in lower operating costs compared to other gases such as argon and helium. To isolate the output gases and control the plasma discharge atmosphere, the plasma was coupled to a reactor. The effect of the gas flow rate, microwave power and initial concentration of compound on the destruction efficiency of the system was evaluated. In this study, trichloroethylene and carbon tetrachloride were used as representative volatile organic compounds to determine the destruction rate of the system. Based on the experimental results, at an applied microwave power less than 1000 W, the proposed system can reduce input concentrations in the ppmv range to output concentrations at the ppbv level. High air flow rates and initial concentrations produced energy efficiency values greater than 1000 g/kW h. The output gases and species present in the plasma were analysed by gas chromatography and optical emission spectroscopy, respectively, and negligible amounts of halogenated compounds resulting from the cleavage of C(2)HCl(3) and CCl(4) were observed. The gaseous byproducts of decomposition consisted mainly of CO(2), NO and N(2)O, as well as trace amounts of Cl(2) and solid CuCl. 相似文献
92.
Vargas-Murga L Garcia-Alvarez A Roman-Viñas B Ngo J Ribas-Barba L van den Berg SJ Williamson G Serra-Majem L 《Food & function》2011,2(12):731-739
The popularity of herbal products, especially plant food supplements (PFS) and herbal medicine is on the rise in Europe and other parts of the world, with increased use in the general population as well as among specific subgroups encompassing children, women or those suffering from diseases such as cancer. The aim of this paper is to examine the PFS market structures in European Community (EC) Member States as well as to examine issues addressing methodologies and consumption data relating to PFS use in Europe. A revision of recent reports on market data, trends and main distribution channels, in addition an example of the consumption of PFS in Spain, is presented. An overview of the methods and administration techniques used to assess individual food consumption as a starting point, including their uses and limitations, as well as some examples of studies that collect Food Supplement (FS) information, including herbal/botanical/plant-derived products are also discussed. Additionally, the intake estimation process of food nutrients is described and used to propose the PFS ingredients intake estimation process. Nationally representative PFS consumption data is scarce in Europe. The majority of studies have been conducted in Scandinavia and the UK. However the heterogeneity of definitions, study design and objectives make it difficult to compare results and extrapolate conclusions. 相似文献
93.
S. Malato Rodríguez J. Blanco Glvez M. I. Maldonado Rubio P. Fernndez Ibez D. Alarcn Padilla M. Collares Pereira J. Farinha Mendes J. Correia de Oliveira 《Solar Energy》2004,77(5):513-524
This paper briefly describes the different collectors used in solar photocatalysis for wastewater treatment and, based on prior experience, the main advantages and disadvantages of each. As the tubular-shape reactor configuration is the most appropriate for handling and pumping water, the compound parabolic collector (CPC) is proposed as an interesting combination of parabolic concentrators and flat static systems and constitutes a good option for solar photochemical applications. The design of compound parabolic concentrators for solar photocatalytic applications is described in detail and 25–50 mm is proposed as the optimum photoreactor diameter, based on the optical characteristics and optimum concentration of the two photocatalytic systems (TiO2 and photo-Fenton) that can be used with sunlight for wastewater treatment. It has been demonstrated that since aluminium is the only metal that is highly reflective in the ultraviolet spectrum of solar radiation, aluminium-based mirrors are the best option. But, especially when exposed to outdoor conditions, aluminium must be protected and, therefore, at the present time, anodised and electropolished aluminium surfaces are considered the most suitable solutions. As the photochemical reactor contain the working fluid, including the catalyst, it must transmit UV sunlight efficiently and be able to work under enough pressure to handle the high volumes resulting from the large number of collectors in an industrial treatment plant, only low-iron glass is proposed as feasible for constructing the photoreactor (collector absorbers). Finally, ray-tracing algorithm simulations are presented as a design tool for the optical configuration of a particular reactor, drawing conclusions for its improvement and assisting in final engineering decision-making. 相似文献
94.
Ulloa JA Rosas-Ulloa P Ulloa-Rangel BE 《Journal of the science of food and agriculture》2011,91(3):572-577
BACKGROUND: The protein isolate obtained from safflower meal by aqueous extraction and ultrafiltration was evaluated for its physicochemical and functional properties. RESULTS: Protein, ash and moisture contents of the safflower protein isolate were 901, 51 and 45 g kg?1 respectively. Its water and oil absorption capacities were 2.22 mL H2O g?1 protein and 2.77 mL oil g?1 protein respectively. Least gelation concentration was 20 g kg?1 at pH 2, 6, 8 and 10 but 100 g kg?1 at pH 4. Emulsifying properties were also affected by the pH: emulsifying activity and emulsion stability at pH 6 were 82.5 and 100% respectively. The highest foaming capacity (126%) occurred at pH 2; however, it increased by 104% with the addition of 0.25 g glucose g?1 protein to the foam system. CONCLUSION: In the light of its functional properties found in this study, safflower protein isolate produced by ultrafiltration is recommended for use as an ingredient in food products such as salad dressing, meat products, mayonnaise, cakes, ice cream and desserts. Copyright © 2010 Society of Chemical Industry 相似文献
95.
Thasanaporn Ungpittagul Arnut Virachotikul Julien Monot Blanca Martín-Vaca Didier Bourissou 《Advanced Synthesis \u0026amp; Catalysis》2024,366(4):733-739
The synthesis of a difunctional P-heterocycle combining phosphonate and ester moieties in a six-membered ring is described. Using trifluoromethane sulfonic acid HOTf as organocatalyst, ring-opening with neopentyl alcohol readily occurs with complete selectivity for O-acyl bond cleavage. In turn, ring-opening polymerization proceeds in a controlled manner when an excess of P-heterocycle is used. Copolymerization with ϵ-caprolactone is also reported and semi-batch conditions are shown to enable regular incorporation of the phosphonate moieties along the polymer chains. 相似文献
96.
Enrique J. Fernandez-Sanchez Leonardo Rubio Javier Diaz Eduardo Ros 《Machine Vision and Applications》2014,25(5):1211-1225
Background subtraction consists of segmenting objects in movement in a video captured by a static camera. This is typically performed using color information, but it leads to wrong estimations due to perspective and illumination issues. We show that multimodal approaches based on the integrated use of color and depth cues produce more accurate and robust results than using either data source independently. Depth is less affected by issues such as shadows or foreground objects similar to background. However, objects close to the background may not be detected when using only range information, being color information complementary in those cases. We propose an extension of a well-known background subtraction technique which fuses range and color information, as well as a post-processing mask fusion stage to get the best of each feature. We have evaluated the method proposed using a well-defined dataset and different disparity estimation algorithms, showing the benefits of our method for fusion color and depth cues. 相似文献
97.
Solvent and relative humidity effect on highly ordered polystyrene honeycomb patterns analyzed by Voronoi tesselation
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Leire Ruiz‐Rubio Itxasne Azpitarte Nuria García‐Huete José Manuel Laza José Luis Vilas Luis M. León 《应用聚合物科学杂志》2016,133(39)
Highly ordered honeycomb‐patterned polystyrene surfaces are efficiently prepared by static breath figure method. The structured arrays can be obtained by casting a dilute solution polymer on glass substrates under various conditions. Tetrahydrofuran and chloroform are used as solvent to form cavities of several micrometers. The analysis of the surfaces indicates nonlinear relation between concentration and pore size in this system. Voronoi tessellations of the polystyrene surfaces at different relative humidity (RH) are achieved, and each conformational entropy determined. Optimum parameters of concentration and RH are obtained for both solvents. Analysis of hole size distribution and conformational entropy demonstrates the high order of the films obtained. This is a promising method for the fabrication of homogeneous and highly porous films from polystyrene. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44004. 相似文献
98.
Total concentrations of Cu and Pb and the speciation of these metals in sediments of the River Tenes are studied in order to establish the extent to which they are polluted and their capacity of remobilization. Five samples taken along the river were analyzed, major components of the sediments were studied using XRF and total Pb and Cu content were determined by AAS. In order to test the accuracy of the digestion methods used (triacid attack with nitric, perchloric and hydrofluoric acids or diacic attack with nitric and hydrochloric acids) for the determination of total trace metal, a standard reference material was also analyzed. Triacid attack is proposed to obtain good results. The results show a highly polluted area (1556 mg kg−1 Cu and 1555 mg kg−1 Pb) in the last sampling site analyzed. For metal speciation, the sequential scheme of Tessier et al. was used. From the results obtained, it can be concluded that Cu content in non-residual fraction is bonded mainly to organic matter, whereas non-residual Pb is mainly associated to iron and manganese oxides. 相似文献
99.
LA Pérula de Torres J Martínez de la Iglesia J Espejo Espejo MV Rubio Cuadrado I Enciso Berge FJ Fonseca del Pozo JM Aranda Lara 《Canadian Metallurgical Quarterly》1997,20(8):425-434
OBJECTIVE: To describe the health status of a population over 60 years and to study their relationship with several socio-demographic variables. DESIGN: A cross-sectional study, population based. SETTINGS: A community. PARTICIPANTS: A randomized sample of 1,103 non institutionalized people over 60 years living in the city of Cordoba (Spain). MEASUREMENTS AND MAIN RESULTS: By mean of a personal interview at home we used the OARS-MFAQ-VE questionnaire. Low self-rated health was associated with the age, to be female sex, a low cultural background, and a low income. Only 5.2% of the study people do not suffered any illness and 56% state that their health problems are major problems for doing their current activities. 4.9% declared to have some degree of physical incapacity. 3.7% of elderly population has an important cognitive deficit. CONCLUSIONS: The majority of elderly people has good health. Age is related with a poor health. Women have more health problems than men. 相似文献
100.
Granular computing is a computational paradigm that mimics human cognition in terms of grouping similar information together. Compatibility operators such as cardinality, orientation, density, and multidimensional length act on both in raw data and information granules which are formed from raw data providing a framework for human-like information processing where information granulation is intrinsic. Granular computing, as a computational concept, is not new, however it is only relatively recent when this concept has been formalised computationally via the use of Computational Intelligence methods such as Fuzzy Logic and Rough Sets. Neutrosophy is a unifying field in logics that extents the concept of fuzzy sets into a three-valued logic that uses an indeterminacy value, and it is the basis of neutrosophic logic, neutrosophic probability, neutrosophic statistics and interval valued neutrosophic theory. In this paper we present a new framework for creating Granular Computing Neural-Fuzzy modelling structures via the use of Neutrosophic Logic to address the issue of uncertainty during the data granulation process. The theoretical and computational aspects of the approach are presented and discussed in this paper, as well as a case study using real industrial data. The case study under investigation is the predictive modelling of the Charpy Toughness of heat-treated steel; a process that exhibits very high uncertainty in the measurements due to the thermomechanical complexity of the Charpy test itself. The results show that the proposed approach leads to more meaningful and simpler granular models, with a better generalisation performance as compared to other recent modelling attempts on the same data set. 相似文献