Comparison of supercritical fluid and hexane extraction methods in extracting kenaf (hibiscus cannabinus) seed oil lipids.

The objective of this study was to investigate and compare fatty acids, tocopherols and sterols of kenaf seed oil extracted by supercritical carbon dioxide and traditional solvent methods. Fatty acids, tocopherols and sterols were determined in the extracted oils as functions of the pressure (400 bar, 600 bar), temperature (40 °C, 80 °C) and CO2 flow rate (25 g/min) using a 1-L extraction vessel. Gas chromatography was used to characterize fatty acids and sterols of the obtained oils while tocopherols were quantified by HPLC. No differences were found in the fatty acid compositions of the various oil extracts and the main components were found to be linoleic (38%), oleic (35%), palmitic (20%) and stearic acid (3%). Extraction of tocopherols using high pressure (600 bar/40 °C, 600 bar/80 °C) gave higher total tocopherols (88.20 and 85.57 mg/100 g oil, respectively) when compared with hexane extraction which gave yield of 62.38 mg/100 g oil. Extraction of kenaf seed oil using supercritical fluid extraction at high temperature (80 °C) gave higher amounts of sterols when compared with hexane extraction

Numerical simulations of aggregate breakup in bounded and unbounded turbulent flows

Breakup of small aggregates in fully developed turbulence is studied by means of direct numerical simulations in a series of typical bounded and unbounded flow configurations, such as a turbulent channel flow, a developing boundary layer and homogeneous isotropic turbulence. The simplest criterion for breakup is adopted, whereas aggregate breakup occurs when the local hydrodynamic stress $\sigma\sim \varepsilon^{1/2}$, with $\varepsilon$ being the energy dissipation at the position of the aggregate, overcomes a given threshold $\sigma_\mathrm{cr}$, which is characteristic for a given type of aggregates. Results show that the breakup rate decreases with increasing threshold. For small thresholds, it develops a universal scaling among the different flows. For high thresholds, the breakup rates show strong differences between the different flow configurations, highlighting the importance of non-universal mean-flow properties. To further assess the effects of flow inhomogeneity and turbulent fluctuations, theresults are compared with those obtained in a smooth stochastic flow. Furthermore, we discuss the limitations and applicability of a set of independent proxies.Comment: 15 pages, 12 figures, Refinded discussion in Section 2.1, results unchange

Quality evaluation of cold-pressed edible oils from Macedonia

The chemical composition and quality of eight pure cold-pressed oils and two blend oils from Macedonia were examined in this work. The highest level of oleic acid was determined in apricot kernel oil and rapeseed oil with abundance of 70.9 and 59.2%, respectively. The highest level of polyunsaturated fatty acids was seen for flaxseed and hemp seed oil with abundance of a-linolenic acid of 55.1% for flaxseed oil and linoleic acid of 57.4% for hemp seed oil. Apricot kernel oil and roasted sesame seed oil had the highest oxidative stability with induction times of 7.6 and 10.9 h. Apricot oil, hemp seed oil, and flaxseed oil had the highest level of total vitamin-E-active compounds with 58.8, 58.1, and 69.7 per 100 g of oil with predomination of g-tocopherol. The highest peroxide number was detected in blend oils (oil 2 and oil 8) with values over 10 meq O2/kg of oil. The highest FFA was detected in rapeseed oil (1.57%). Roasted and unroasted sesame seed oils had relatively high specific extinction (K232 values 3.55 and 3.33, respectively). However, the highest UV extinction had a blend of pumpkin seed oil and sunflower oil with a value of 3.84. Practical applications: The results of this study can be applied for determination of the most important major and minor components responsible for quality evaluation of cold-pressed oils. Statistical results indicated a strong relationship between the level of monounsaturated fatty acids in the oil and their oxidative stability. The level of tocopherols and other vitamin-E-related compounds was in strong relationship with the antioxidant activity of the oils measured by the DPPH method. Phytosterols, as minor compounds present in the oils, did not contribute significantly to the total antioxidant potential of the oils but, their levels in particular oils, together with fatty acids, can be useful and reliable markers for the purity of the oils and determination of the composition of blends

Evaluación química de algunas semillas de cítricos, un residuo agroindustrial como nueva fuente potencial de aceites vegetales

The seed oils from seven Turkish and ten Vietnamese varieties of Citrus fruits were examined for their fatty acid composition, tocopherols and sterol contents. The oil contents of the samples varied between 32.1 g/100 g and 58.8 g/100 g. The major fatty acid of the extracted seed oils was oleic (12.8-70.1%), followed by linoleic (19.5-58.8%) and palmitic (5.1-28.3%). Stearic, vaccenic, linolenic and arachidic acids were found at low levels. The total content of vitamin E active compounds in the oils ranged between 0.8 and 21.0 mg/100 g. The predominant isomers were α- and γ-tocopherol, with approximate equal amounts between about 0.4 and 17.5 mg/100 g. The total sterol contents of the oils were found between 1310.54 and 3986.58 mg/kg, with β -sitosterol as the predominant sterol that accounted for more than 70% of the total amount of sterols. Other sterols, campesterol (8.03-15.26%), stigmasterol (2.55-7.69%), ∆5-avenasterol (1.80-5.67%), cholesterol (0.83-2.70%) and chlerosterol (0.93-1.78%) were detected in most of the oils. The results of the present study indicate that the seed oils of Citrus fruits are considered to be a potential oil source due to their fatty acid composition and important tocopherol and sterol, and might be used for edible applications as well as the production of potential value-added products.Aceites de semillas de siete y diez variedades de frutas cítricas turcas y de Vietnam respectivamente, fueron examinadas por su composición en ácidos grasos, tocoferoles y esteroles. El contenido de aceite de las muestras varió entre 32.1 g/100 g y 58.8 g/100 g. El principal ácido graso de los aceites extraídos de las semillas fue oleico (12.8 a 70.1%), seguido por linoleico (19.5-58.8%) y palmítico (5.1 a 28.3%). Los ácidos esteárico, vacénico, linolénico y araquídico se encontraron en niveles bajos. El contenido total de compuestos de vitamina E activa en los aceites varió entre 0.8 y 21.0 mg/100 g. Los isómeros predominantes fueron α- y γ-tocoferol, con aproximadamente la misma cantidad, entre 0.4 y 17.5 mg/100 g. El contenido de esteroles totales de los aceites se encontró entre 1310.54 y 3986.58 mg/kg, con β-sitosterol como el esterol predominante representando más del 70% de la cantidad total de esteroles. Otros esteroles, campesterol (8.03-15.26%), estigmasterol (2.55-7.69%), ∆5-avenasterol (1.80-5.67%), colesterol (0.83 a 2.70%) y clerosterol (0.93-1.78%) se detectaron en la mayoría de los aceites. Los resultados del presente estudio indican que los aceites de semillas de cítricos se consideran una fuente potencial de aceite debido a la importante composición de ácidos grasos, tocoferoles y esteroles, y podría ser utilizado para aplicaciones alimenticias y para la producción de posibles productos de valor añadido

Fatty acid, Tocopherol and Sterol Composition in Sea buckthorn (Hippophae rhamnoides L.) of Mongolia

The content and composition of lipids isolated from seed and pulp of sea buckthorn were investigated. Fatty acids and sterols were analyzed by CGC while tocopherols were analyzed by HPLC. 12.67% glyceride was found in the seed. The oil of sea buckthorn seed oil showed low levels of saturated fatty acids in comparison with the buckthorn pulp oil. Palmitic (7.13%), oleic (15.85%), linoleic (36.9%) and linolenic acids (31.11%) predominated in the seed oil. Palmitic (29.17%), palmitoleic (32.86%), oleic (4.92%), vaccenic (9.35%) and linoleic (16.08%) fatty acid was dominating in the pulp oil. The primary tocopherol of sea buckthorn seed and pulp oil were α- tocopherol and γ-tocopherol (46.54mg/100g, 59.02mg/100g). Seed oil contains more (94.34mg/100g) total sterols than pulp (90.25mg/100g) oil.DOI: http://dx.doi.org/10.5564/mjc.v12i0.187 Mongolian Journal of Chemistry Vol.12 2011: 126-130

Fatty acid, Tocopherol and Sterol Composition in Sea buckthorn (Hippophae rhamnoides L.) of Mongolia

The content and composition of lipids isolated from seed and pulp of sea buckthorn were investigated. Fatty acids and sterols were analyzed by CGC while tocopherols were analyzed by HPLC. 12.67% glyceride was found in the seed. The oil of sea buckthorn seed oil showed low levels of saturated fatty acids in comparison with the buckthorn pulp oil. Palmitic (7.13%), oleic (15.85%), linoleic (36.9%) and linolenic acids (31.11%) predominated in the seed oil. Palmitic (29.17%), palmitoleic (32.86%), oleic (4.92%), vaccenic (9.35%) and linoleic (16.08%) fatty acid was dominating in the pulp oil. The primary tocopherol of sea buckthorn seed and pulp oil were α- tocopherol and γ-tocopherol (46.54mg/100g, 59.02mg/100g). Seed oil contains more (94.34mg/100g) total sterols than pulp (90.25mg/100g) oil.DOI: http://dx.doi.org/10.5564/mjc.v12i0.187 Mongolian Journal of Chemistry Vol.12 2011: 126-130

Many Objective Particle Swarm Optimisation: An Investigation into Strengthening Convergence by Controlling Dominance Area

The application of single and multi-objective particle swarm optimisation (PSO) is widespread, however in many-objective optimisation (problems with four or more competing objectives) traditional PSO has been less well examined. Recent progress on many-objective evolutionary optimisers has lead to the adoption of a variety of non-Pareto quality measures, it is therefore of interest to see how well PSO copes in this domain, and how non-Pareto quality measures perform when integrated into PSO. Here we review the current state of the art in multi- and many-objective PSO optimisation. We compare and contract the performance of canonical PSO, using a wide range of many-objective quality measures, on a number of different parametrised test functions for up to 30 competing objectives. We examine quality measures as selection operators for guides when truncated non-dominated archives of guides are maintained, and maintenance operators, for choosing which solutions should be maintained as guides from one generation to the next. We investigate in detail two Pareto strengthening methods, Controlling Dominance Area of Solutions (CDAS) and Self-Controlling Dominance Area of Solutions (S-CDAS). We find that CDAS and S-CDAS perform exceptionally well as a quality measures to determine archive membership for global and local guides. However, for convergence only at the cost of diversity and spread across the optimal front, single objective canonical PSO run using a linear sum of objectives, has the best performance overall

Análise do perfil dos empreendedores e descrição dos empreendimentos do município de senador Georgino Avelino/ RN

MonografiaNos últimos anos é perceptível que o termo empreendedorismo se tornou um assunto bem difundido no Brasil e no mundo, é considerado de fundamental importância para o desenvolvimento econômico de uma sociedade, impulsiona o crescimento de cidades, estados e países, motiva à criação e o uso de novas tecnologias, produtos e serviços. Desse modo, torna-se necessário o levantamento de dados com o intuito de se obter informações que possam ser usadas como parâmetros para caracterizar o perfil dos empreendedores e dos empreendimentos do município de Senador Georgino Avelino/RN. Para o desenvolvimento deste trabalho foi realizado uma pesquisa documental, bibliográfica e de campo. Na pesquisa desenvolvida em campo, foi aplicado um questionário com perguntas objetivas e subjetivas, com o intuito de identificar a atual situação do município em relação ao empreendedorismo. Através da análise dos resultados, notou-se que o gênero masculino predomina na atuação empresarial da cidade, e em sua maioria os empresários apresentam entre 31 a 40 anos de idade. O principal porte das empresas é a Microempreendedor Individual (MEI), e dentre todos atividades empresariais desenvolvidas na cidade em questão, a principal é a do ramo comercial.Trabalho não financiado por agência de fomento, ou autofinanciad