Academic literature on the topic 'Central composite rotatable design (CCRD)'
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Journal articles on the topic "Central composite rotatable design (CCRD)"
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Morandim-Giannetti, Andreia de Araújo, Samantha Regina Rubio, Regina Freitas Nogueira, Fernando dos Santos Ortega, Octaviano Magalhães Junior, Paulo Schor, and Patrícia Alessandra Bersanetti. "Characterization of PVA/glutaraldehyde hydrogels obtained using Central Composite Rotatable Design (CCRD)." Journal of Biomedical Materials Research Part B: Applied Biomaterials 106, no. 4 (July 31, 2017): 1558–66. http://dx.doi.org/10.1002/jbm.b.33958.
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Rybka, Ana Cecília Poloni, Sérgio Tonetto De Freitas, Acácio Figueiredo Netto, and Aline Camarão Telles Biasoto. "Central composite rotatable design approach to optimize ‘Italia’ raisin drying conditions." Comunicata Scientiae 6, no. 4 (December 29, 2015): 454. http://dx.doi.org/10.14295/cs.v6i4.993.
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Considering its high demand and limited production, raisin represents an important alternative to diversify grape processed products around the world. The aim of this study was to determine the best combination between drying temperature and time required to reach the highest consumer acceptance of ‘Italia’ raisin produced in the semi-arid climate in Brazil. The drying conditions were combinations between drying temperatures of 50, 56, 70, 84 and 90°C and drying times of 16, 22, 35, 48 and 54 hours, following a central composite rotational design (CCRD). The best combination between drying temperature and time was estimated to be 70°C for 35 hours (h), based on overall consumer acceptance. According to the statistical analysis used, drying at 70 °C for 35h and at 59 °C for 28h results in equal overall consumer acceptance, being the second option the more economical. Taste and texture, raisin chroma values and pH were more positively correlated to overall acceptance. The results indicate that drying at 59ºC for 28 h is the most efficient drying condition for raisins from ‘Italia’ grapes grown in Brazilian semi-arid condition. This study uses a new approach based on the central composite rotatable design to determine the most efficient drying temperature and time for ‘Italia’ raisins.
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Gunawan, Erin Ryantin, and Dedy Suhendra. "FOUR-FACTOR RESPONSE SURFACE OPTIMIZATION OF THE ENZYMATIC SYNTHESIS OF WAX ESTER FROM PALM KERNEL OIL." Indonesian Journal of Chemistry 8, no. 1 (June 17, 2010): 83–90. http://dx.doi.org/10.22146/ijc.21653.
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The synthesis of wax ester using refined, bleached and deodorized (RBD) palm kernel oil (PKO) and oley alcohol catalyzed by Lipozyme IM was carried out. Response surface methodology (RSM) based on a five-level, four-factor central composite rotatable design (CCRD) was used to evaluate the interactive effects of synthesis, of reaction time (5-20 h), temperature (20-50 oC), amount of enzyme (0.1-0.2 g) and substrate molar ratio (palm kernel oil to oleyl alcohol, 1:1-1:5) on the percentage yield of wax esters. The optimum condition conditions derived via RSM were reaction time 8.46 h, temperature 44.4 oC, amount of enzyme 0.182 g, substrate molar ratio 1 to 3.7. The actual experimental yield was 92.9 % under optimum condition, which good accordance to the maximum predicted value of 92.4 %. Keywords: response surface methodology, central composite rotatable design, palm kernel oil, lipozyme, alcoholysis, wax ester
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Cavalcante, Kiany S. B., Maria N. C. Penha, Karlene K. M. Mendonça, Hilton C. Louzeiro, Antonio C. S. Vasconcelos, Adeilton P. Maciel, Antonio G. de Souza, and Fernando C. Silva. "Optimization of transesterification of castor oil with ethanol using a central composite rotatable design (CCRD)." Fuel 89, no. 5 (May 2010): 1172–76. http://dx.doi.org/10.1016/j.fuel.2009.10.029.
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Tavares, Leticia Cardoso Madureira, Alisson Carraro Borges, Teresa Cristina Fonseca da Silva, and André Pereira Rosa. "Guazuma ulmifolia: an environmentally friendly coagulant aid for water treatment." Water Science and Technology 82, no. 8 (September 8, 2020): 1579–85. http://dx.doi.org/10.2166/wst.2020.431.
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Abstract In the present work the use of a promising novel coagulant aid, Guazuma ulmifolia, was optimized to treat synthetic water using central composite being highly efficient at rotatable design (CCRD). The factors evaluated for the coagulation-flocculation process were coagulants dosages and pH. A model to describe the coagulation-flocculation process was successfully obtained. The model was validated using 5 mg L−1 aluminum sulfate, 2.5 mg L−1G. ulmifolia and pH 9, achieving excellent agreement with observed values.
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Regalado-Méndez, Alejandro, Juan Mentado-Morales, Ever Peralta-Reyes, Carlos Estrada-Vázquez, Gerardo Martínez-Villa, Mario E. Cordero, and Luis G. Zárate. "Biodiesel Production from Jatropha oaxacana Oil by Reactive Vacuum Distillation: Optimization by Response Surface Methodology." Key Engineering Materials 737 (June 2017): 385–92. http://dx.doi.org/10.4028/www.scientific.net/kem.737.385.
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The application of Response Surface Methodology (RSM) and Central Composite Rotatable Design (CCRD) for modeling and optimization of the influence of three operating variables (mass of catalyst, MeOH/Oil molar ratio, and temperature) on performance of Reactive Vacuum Distillation (RVD) to increase biodiesel yield is discussed in this work. Changes in RVD performance during biodiesel production were evaluated by using RSM and CCRD. A mathematical equation to model biodiesel production by RVD was derived from computer simulation programming by applying a least squares method using MATLAB® v. R2016a. Predicted values were found to be in good agreement with experimental values (with R2 = 0.934). Optimal conditions for the production of ethyl esters were: Temperature: 31.2 °C, MeOH/Oil molar ratio: 5.65:1, and mass of catalyst: 0.1344 g.
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Pezzin, Ana Paula Testa, Jaqueline Boldt Capellari, Eduarda Zeni Neves, Michele Cristina Formolo Garcia, Giannini Pasiznick Apati, and Andrea Lima Dos Santos Schneider. "Application of response surface methodology and central composite rotatable design (CCDR) for modelling the influence of agro-industrial waste in lactic acid biosynthesis." Acta Biológica Catarinense 6, no. 4 (December 16, 2019): 51. http://dx.doi.org/10.21726/abc.v6i4.726.
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Lactic acid (LA) is one of the most important organic acids, with a wide range of industrial and biotechnological applications and can be produced by chemical synthesis and microbial culture. However, the biotech pathway is generally preferred because it provides an optically pure product. In this context, the purpose of this work was to evaluate LA biosynthesis by Lactobacillus amylovorus using molasses as carbon source (CS) and corn steep liquor as nitrogen source (NS) in a central composite rotatable design (CCRD) varying the concentration CS and NS, as well as to validate the model. The method for microbial culture followed an experimental design of the CCRD type, conducted without agitation, at 37ºC in Erlenmeyer flask, with pH in spontaneous evolution. The results showed that, using molasses and corn steep liquor as alternative sources, LA production ranged from 2.8 to 4.6 g/L, respectively, with the most favourable condition being 40.0 g of molasses and 250 g of corn steep liquor. It was possible, from the experimental design, to ascertain the selection of the best conditions for the microbial culture, demonstrating the feasibility of replacing CS and NS by agro-industrial waste, thus reducing the cost of producing LA.
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Singh, Balbir, Sudhir Kumar, and Jatinder Kumar. "Multi-Objective Optimization in Electrical Discharge Machining of 6061 Al/SiCp Using RSM and NSGA-II." Key Engineering Materials 748 (August 2017): 207–11. http://dx.doi.org/10.4028/www.scientific.net/kem.748.207.
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In this paper, response surface methodology (RSM) and non sorting genetic algorithm (NSGA-II) are used to optimize the multi-responses of electrical discharge machining of Aluminum Alloy 6061/10%SiCp composite. Experiment is performed to evaluates the effects of process parameters namely peak current, pulse on time, pulses off time and gap voltage on the responses material removal rate (MRR) and tool wear rate (TWR). The central composite rotatable design (CCRD) is utilized to design the experiment using RSM. Analysis of Variance (ANOVA) test is performed to validate model and to further establish the mathematical relation between process parameters and responses. Results are analyzed using ANOVA models. NSGA-II is used to optimize two conflicting responses i.e MRR and TWR. Finally results are validated by confirmatory experiment.
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Yasin, Yamin, Maszlin Mohamad, and Faujan B. H. Ahmad. "The Application of Response Surface Methodology for Lead Ion Removal from Aqueous Solution Using Intercalated Tartrate-Mg-Al Layered Double Hydroxides." International Journal of Chemical Engineering 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/937675.
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Layered double hydroxide intercalated with tartrate (tartrate-Mg-Al) was used as an adsorbent to remove lead ions from aqueous solutions. The effects of various optimization parameters such as contact time, solution pH, lead ion concentrations, and adsorbent dosage were investigated by the use of Response Surface Methodology (RSM). The Response Surface Methodology (RSM) based on a four-level four-variable Central Composite Rotatable Design (CCRD) was employed to evaluate the interactive effects of the various optimization parameters. The parameters were contact time (6–10 h), solution pH (1–3), adsorbent dosage (0.06–0.1 g), and lead ion concentrations (10–30 mg/L). The percentage of lead ions removal for each of the parameters studied was determined by Inductively Coupled Plasma-Optical Emission Spectrophotometer. Simultaneously by increasing contact time and amount of dosage of tartrate-Mg-Al used the percentage of lead ions removal from aqueous solution will increase; however, the percentage removal decreases with an increase in pH and concentrations of lead ions. The experimental percentage removal recorded under optimum conditions was compared well with the maximum predicted value from the RSM, which suggest that Central Composite Rotatable Design of RSM can be used to study the removal of lead from aqueous solution by the use of tartrate-Mg-Al as an adsorbent.
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Santos, Fernanda Godoy, Layanne Andrade Mendonça, and Hilário Cuquetto Mantovani. "A central composite rotatable design (CCRD) approach to study the combined effect of antimicrobial agents against bacterial pathogens." World Journal of Microbiology and Biotechnology 31, no. 9 (June 17, 2015): 1361–67. http://dx.doi.org/10.1007/s11274-015-1884-4.
Full textDissertations / Theses on the topic "Central composite rotatable design (CCRD)"
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Awadallak, Jamal Abd. "Uso de ultrassom na hidrólise enzimática do óleo de palma: síntese de diacilglicerol." Universidade Estadual do Oeste do Parana, 2012. http://tede.unioeste.br:8080/tede/handle/tede/1901.
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Previous issue date: 2012-02-15Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Diacylglycerol rich oils have its organoleptic characteristics very similar to those of conventional edible oils, but these oils do not tend to accumulate in the body, even when consumed in high quantities, making them a great resource in the fight against obesity. Palm oil ranks first the world production of edible oils mainly due to its low cost. This work aimed to propose a new technology for enzyme production using diacylglycerol lipase Lipozyme RM IM and ultrasound to promote water in oil emulsions, which increases the interfacial area of the system leading to higher reaction rates compared to conventional enzymatic processes. . The reactions were carried out at 55 °C with two different methods. First, the reaction system was exposed to ultrasonic waves for the whole reaction time, which led to enzymatic inactivation and water evaporation. Ultrasound was then used to promote emulsification of the water/oil system before the hydrolysis reaction, avoiding contact between the probe and the enzymes. Achieved conversions were superior to the conventional method further hydrolysis rate when the ultrasound is employed for emulsion formation was significantly greater. For 12 hours of reaction the conversion was 85% higher than the conventional method and 15% higher for a period of 24 hours of reaction. . An experimental design was used to optimize the ultrasound-related parameters and maximize the hydrolysis rate, and in these conditions, with a change in equilibrium, DAG production was evaluated.Better reaction conditions were achieved for the second method: 11.20 wt% (water+oil mass) water content, 1.36 wt% (water+oil mass) enzyme load, 12 h of reaction time, 1.2 min and 200 W of exposure to ultrasound. In these conditions diacylglycerol yield was 37.69 wt%.
Óleos enriquecidos com diacilglicerol possuem características organolépticas muito semelhantes às dos óleos comestíveis convencionais, porém, estes óleos não tendem a se acumular no organismo, mesmo quando consumidos em altas quantidades, tornando-os um grande recurso no combate à obesidade. O óleo de palma está no topo da produção mundial de óleos comestíveis principalmente devido ao seu baixo custo. Este trabalho teve como objetivo propor uma nova tecnologia para a produção enzimática de diacilglicerol empregando a lipase Lipozyme RM IM e utilizando ultrassom como gerador de emulsões de água em óleo, o que aumenta a área interfacial do sistema conduzindo a maiores taxas de reação em relação aos processos enzimáticos convencionais. A hidrólise parcial do óleo de palma foi realizada em meio livre de solventes a 55 °C em duas etapas distintas e comparadas com reações em condições semelhantes sem o uso do ultrassom. Primeiramente o sistema reacional foi exposto às ondas ultrassônicas, o que levou a taxas iniciais de reação elevadas, porém, as conversões obtidas foram baixas, em função da desativação enzimática e da evaporação de água, pelo longo período de exposição ao ultrassom. Posteriormente, utilizou-se o ultrassom para gerar emulsões antes a etapa reacional, não permitindo seu contato com o sistema contendo a enzima. As conversões obtidas foram superiores ao método convencional, além disso, taxa de hidrólise quando se empregou o ultrassom para a formação de emulsões foi significativamente maior. Para 12 horas de reação a conversão foi 85% superior ao método convencional e de 15% superior para um período de 24 horas de reação. Foi desenvolvido um planejamento fatorial, o delineamento central composto rotacional para avaliar os efeitos das variáveis tempo de exposição ao ultrassom, potência do ultrassom e razão água/óleo na conversão em ácidos graxos livres da reação, sendo que a razão água/óleo e o produto tempo x potência apresentaram os maiores efeitos. Nas melhores condições, foi produzido um óleo concentrado com 37,69% de DAG em de 12h de reação, exposto ao ultrassom por 1,2min à 200W.
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Gonçalves, Rafael Henrique. "Aplicação da metodologia de superfície de resposta na otimização da remediação de um solo arenoso contaminado com cobre /." Rio Claro : [s.n.], 2009. http://hdl.handle.net/11449/92744.
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Orientador: José Ricardo SturaroBanca: Paulo Milton Barbosa Landim
Banca: Adriana Cavalieri Sais
Resumo: A contaminação de solos por metais pesados constitui-se em um problema ambiental que, geralmente, produz riscos permanentes à saúde humana e aos sistemas ecológicos, portanto com freqüente necessidade de intervenção por meio de tecnologias de remediação. Uma de tecnologias alternativas para a remediação de solos contaminados com metais pesados é a lavagem de solos in situ, cujo processo de remoção de contaminantes do solo envolve a percolação de uma solução extratora. Este trabalho propõe o emprego da metodologia de superfície de resposta para ajustar um modelo que aponte combinações entre os parâmetros da solução extratora - concentração de etileno diaminotetraacético dissódico (Na2EDTA), volume e pH da solução extratora - que possibilitem reduzir a concentração de cobre de um solo arenoso, a níveis de risco inferiores aos valores de intervenção para os cenários de exposição adotados pela Companhia Ambiental do Estado de São Paulo. Para tanto, realizou-se uma série de ensaios de lixiviação em coluna utilizando-se um Neossolo Flúvico artificialmente contaminado (1257,3 mg kg-1). Os ensaios foram conduzidos em triplicata e configuraram um arranjo experimental do tipo planejamento composto central rotacional, composto por 15 diferentes combinações dos parâmetros da solução extratora e de uma replicata no ponto central. Os resultados obtidos mostraram que a metodologia de superfície de resposta possibilitou o ajuste de um modelo, que aponta combinações de concentração de Na2EDTA, volume e pH da solução extratora que permitem reduzir a concentração de cobre de um determinado Neossolo Flúvico a valores inferiores aos dispostos pela Companhia Ambiental do Estado de São Paulo, para os cenários de exposição industrial, residencial, agrícola ou de proteção máxima.
Abstract: The soil contamination by heavy metals is an environmental problem that usually produces permanent risk to human health and ecological systems that often need the intervention through remediation technologies. An alternative remediation technology for soils contaminated with heavy metals is the soil flushing, which the contaminant removing process involves the percolation of an extraction solution. This work proposes the use of response surface methodology to adjust a model that points out combinations among the parameters of the extraction solution -ethylenediaminetetraacetic disodium (Na2EDTA) concentration, volume e pH of extraction solution -to reduce the concentration of copper in a sandy soil to risk levels lower than the intervention levels for exposure scenarios adopted by Environmental Company of Sao Paulo State. Thus, a series of tests in leaching column was carried out using a Fluvisol artificially contaminated (1257,3 mg kg-1). The tests were conducted in triplicate and setup an experimental array of type central composite rotatable design, composed of 15 different combinations of the parameters of the extraction solution and one replicate in the center point. The results showed that the response surface methodology allowed the fit of a model that identifies combinations of Na2EDTA concentration, volume and pH of the extraction solution to reduce the concentration of copper in a Fluvisol to values lower than those adopted by Environmental Company of Sao Paulo State for the exposure scenarios, namely industrial, residential, agricultural or maximum protection.
Mestre
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Brandão, Kiany Sirley Ribeiro. "OTIMIZAÇÃO DO PROCESSO DE PRODUÇÃO DE BIODIESEL METÍLICO E ETÍLICO DO ÓLEO DE MAMONA (Ricinus Communis L.) APLICANDO UM DELINEAMENTO COMPOSTO CENTRAL ROTACIONAL (DCCR)." Universidade Federal do Maranhão, 2007. http://tedebc.ufma.br:8080/jspui/handle/tede/895.
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Previous issue date: 2007-08-29Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The biodiesel is a biofuel obtained from renewable sources, as vegetable oils and animal fats. The castor seeds (Ricinus communis L.) have a medium content of oil of 47%. This oil when transformed in biodiesel produces a fuel with a series of environmental advantages in relation to petroleum diesel. Therefore in this work it was made the optimization of the production process of the methyl and ethyl biodiesel from castor oil, varying the reaction time, the catalyst amount and the oil:alcohol ratio (methanol or ethanol) using a Central Rotatable Composite Design (CRCD) symmetrical and of second order, constituted of two parts: the factorial 2n, with central points, and the axial part. With base in this factorial planning, surfaces and curves of responses and variance analysis, it was evaluated the effects and the significance of the models for the responses variables, biodiesel yield in mass and the esters content. For the production of methyl biodiesel, the greater biodiesel yield in mass is reached when oil/methanol molar ratio 1:4-1:5; 0,4-1,2% of KOH and time reaction 20-100 min, is used. In function of the esters content, the oil/methanol molar ratio should be between 1:10 and 1:11,36, KOH concentration between 1,4 and 2,34 and reaction time between 120 and 140 min. The regression models of the methyl biodiesel for ANOVA appropriately explained at the level of 95%, the data variation (R2 = 0,90567, for yield biodiesel and R2 = 0,7654, for the esters content). For the production of the ethyl biodiesel, the results of the factorial planning 23 showed that the oil/ethanol ratio and the KOH concentration went statisticaly significant to the biodiesel yield in mass and content of esters. The maximum yield can be reached when oil/ethanol molar ratio between 1:10,4 and 1:12,35; 1,4 to 2% of KOH and 60- 100 min of reaction, is used. In function of the esters content, the oil/ethanol molar ratio should be between 1:10,5 and 1:12,35, concentration of KOH between 1,4 and 2,0 % and time of reaction between 60 and 120 min. The regression models explained the variation of the data appropriately (R2 = 0,71811, for biodiesel yield and for esters content, R2 = 0,95217) and they acted significantly, to 95% of trust limit, the relationship between the independent variables and the response. The samples of the methyl and ethyl biodiesel of castor oil, in the optimized conditions, they are inside of the limits preset by National Agency of the Petroleum, Natural Gas and Biofuels.
O biodiesel é um biocombustível obtido a partir de fontes renováveis como óleos vegetais e gorduras animais. As sementes de mamona (Ricinus communis L.) possuem um teor médio de óleo de 47 %, que ao ser transformado em biodiesel produz um combustível com uma série de vantagens ambientais em relação ao diesel de petróleo. Portanto neste trabalho fez-se a otimização do processo de produção do biodiesel metílico e etílico a partir de óleo de mamona, variando o tempo de reação, a quantidade de catalisador e a relação de óleo:álcool (metanol ou etanol) empregando um Delineamento Composto Central Rotacional (DCCR) simétrico e de segunda ordem, constituído de duas partes: o fatorial 2n, com pontos centrais, e a parte axial. Com base neste planejamento fatorial, superfícies e curvas de respostas e análise de variância foram realizadas a avaliação dos efeitos e a significância dos modelos para as variáveis de respostas, rendimento em massa do biodiesel e o teor de ésteres. Para a produção de biodiesel metílico, o maior rendimento em massa de biodiesel é alcançado quando se usa razão molar óleo/metanol 1:4-1:5; 0,4-1,2 % de KOH e 20-100 min de reação. Em função do teor de ésteres, a razão molar óleo:metanol deve estar entre 1:10 e 1:11,36, concentração de KOH entre 1,4 e 2,34 e tempo de reação entre 120 e 140 min. Os modelos de regressão do biodiesel metílico avaliados pela ANOVA explicaram adequadamente ao nível de 95%, a variação dos dados (R2 = 0,90567, para rendimento biodiesel e R2 = 0,7654, para o teor de ésteres). Para a produção do biodiesel etílico, os resultados do planejamento fatorial 23 mostraram que a razão óleo:etanol e a concentração de KOH foram estatisticamente significativos para o rendimento em massa de biodiesel e teor de ésteres. O máximo rendimento pode ser alcançado quando se usa razão molar óleo/etanol entre 1:10,4 e 1:12,35; 1,4 a 2 % de KOH e 60-100 min de reação. Em função do teor de ésteres, a razão molar óleo:etanol deve estar entre 1:10,5 e 1:12,35, concentração de KOH entre 1,4 e 2,0 % e tempo de reação entre 60 e 120 min. Os modelos de regressão explicaram adequadamente a variação dos dados (R2 = 0,71811, para rendimento biodiesel e para o teor de ésteres, R2 = 0,95217) e representaram significativamente, a 95% de limite de confiança, a relação entre as variáveis independentes e a resposta. As amostras do biodiesel metílico e etílico de mamona, nas condições otimizadas, encontram-se dentro dos limites preestabelecidos pela Agência Nacional do Petróleo, Gás Natural e Biocombustíveis.
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Gonçalves, Rafael Henrique [UNESP]. "Aplicação da metodologia de superfície de resposta na otimização da remediação de um solo arenoso contaminado com cobre." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/92744.
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A contaminação de solos por metais pesados constitui-se em um problema ambiental que, geralmente, produz riscos permanentes à saúde humana e aos sistemas ecológicos, portanto com freqüente necessidade de intervenção por meio de tecnologias de remediação. Uma de tecnologias alternativas para a remediação de solos contaminados com metais pesados é a lavagem de solos in situ, cujo processo de remoção de contaminantes do solo envolve a percolação de uma solução extratora. Este trabalho propõe o emprego da metodologia de superfície de resposta para ajustar um modelo que aponte combinações entre os parâmetros da solução extratora – concentração de etileno diaminotetraacético dissódico (Na2EDTA), volume e pH da solução extratora – que possibilitem reduzir a concentração de cobre de um solo arenoso, a níveis de risco inferiores aos valores de intervenção para os cenários de exposição adotados pela Companhia Ambiental do Estado de São Paulo. Para tanto, realizou-se uma série de ensaios de lixiviação em coluna utilizando-se um Neossolo Flúvico artificialmente contaminado (1257,3 mg kg-1). Os ensaios foram conduzidos em triplicata e configuraram um arranjo experimental do tipo planejamento composto central rotacional, composto por 15 diferentes combinações dos parâmetros da solução extratora e de uma replicata no ponto central. Os resultados obtidos mostraram que a metodologia de superfície de resposta possibilitou o ajuste de um modelo, que aponta combinações de concentração de Na2EDTA, volume e pH da solução extratora que permitem reduzir a concentração de cobre de um determinado Neossolo Flúvico a valores inferiores aos dispostos pela Companhia Ambiental do Estado de São Paulo, para os cenários de exposição industrial, residencial, agrícola ou de proteção máxima.
The soil contamination by heavy metals is an environmental problem that usually produces permanent risk to human health and ecological systems that often need the intervention through remediation technologies. An alternative remediation technology for soils contaminated with heavy metals is the soil flushing, which the contaminant removing process involves the percolation of an extraction solution. This work proposes the use of response surface methodology to adjust a model that points out combinations among the parameters of the extraction solution –ethylenediaminetetraacetic disodium (Na2EDTA) concentration, volume e pH of extraction solution –to reduce the concentration of copper in a sandy soil to risk levels lower than the intervention levels for exposure scenarios adopted by Environmental Company of Sao Paulo State. Thus, a series of tests in leaching column was carried out using a Fluvisol artificially contaminated (1257,3 mg kg-1). The tests were conducted in triplicate and setup an experimental array of type central composite rotatable design, composed of 15 different combinations of the parameters of the extraction solution and one replicate in the center point. The results showed that the response surface methodology allowed the fit of a model that identifies combinations of Na2EDTA concentration, volume and pH of the extraction solution to reduce the concentration of copper in a Fluvisol to values lower than those adopted by Environmental Company of Sao Paulo State for the exposure scenarios, namely industrial, residential, agricultural or maximum protection.
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LI, MING-CHANG, and 李明昌. "A study on global precision rotatable central composite design and rotatable evolutionary operation." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/95933092954109707837.
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Hyder, Md Nasim. "Preparation, Characterization and Performance of Poly(vinyl alcohol) based Membranes for Pervaporation Dehydration of Alcohols." Thesis, 2008. http://hdl.handle.net/10012/4014.
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Pervaporation (PV), a non-porous membrane separation process, is gaining considerable attention for solvent separation in a variety of industries ranging from chemical to food and pharmaceutical to petrochemicals. The most successful application has been the dehydration of organic liquids, for which hydrophilic membranes are used. However, during pervaporation, excessive affinity of water towards hydrophilic membranes leads to undesirable swelling (water absorption) of the membrane matrix. To control swelling, often hydrophilic membranes are crosslinked to modify physicochemical (surface and bulk) properties. Since the transport of species in pervaporation is governed by sorption (affected by surface and bulk properties) and diffusion (affected by bulk properties), it is essential to study the effect of crosslinking on the surface and bulk physicochemical properties and their effects on separation performance.
This thesis focuses on the effect of crosslinking on the physicochemical properties (e.g., crystallinity, hydrophilicity, surface roughness) of hydrophilic polymeric membranes and their dehydration performance alcohol-water mixtures. Poly(vinyl alcohol), PVA was used as the base polymer to prepare membranes with various morphologies such as homogeneous, blended (with Chitosan, CS) and composite (with poly(sulfone), PSf) structures. Before applying the crosslinked membranes for the PV dehydration of alcohols, the physicochemical characterization were carried out using Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR), X-Ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), tensile testing, contact angle and swelling experiments.
The crosslinked membranes showed an increase in surface hydrophobicity from the contact angle measurements as compared to the uncrosslinked membranes. AFM surface topography showed that the membrane surfaces have nodular structures and are rough at the nanometer scale and affected by the crosslinking conditions such as concentration and reaction time. Surface hydrophobicity and roughness was found to increase with increasing degree of crosslinking. DSC measurements showed an increase in melting temperature of the polymer membranes after crosslinking. For the PV dehydration of ethanol, a decrease in flux and an increase in selectivity were observed with increase in the degree of crosslinking.
Effects of membrane thickness (of PVA layer) for crosslinked PVA-PSf composite membranes were studied on PV dehydration of ethanol. Total flux and selectivity were statistically analyzed as a function of the membrane thickness. In general, the outcome agrees with the solution-diffusion (S-D) theory: the total flux was found to be significantly affected by the PVA layer thickness, while the selectivity remains nearly unaffected. Using the S-D theory, the mass transfer resistance of the selective layers was calculated and found to increase with thickness. The relatively small change observed for selectivity has been related to the crosslinking of the PVA layer that increases the surface hydrophobicity of the membrane.
Chitosan-Poly(vinyl alcohol), or CS-PVA, blended membranes were prepared by varying the blending ratio to control membrane crystallinity and its effect on the PV dehydration of ethylene glycol. The blended membranes were crosslinked interfacially with trimesoyl chloride (TMC)/hexane. The crystallinity of the membrane was found to decrease with increasing CS wt% in the blend. Although the crosslinked CS-PVA blend membranes showed improved mechanical strength, they became less flexible as detected in tensile testing. The resulting crosslinked CS-PVA blended membranes showed high flux and selectivity simultaneously, for 70-80wt% CS in the blend. The effect of feed flow-rate was studied to find the presence of concentration polarization for 90wt% EG in feed mixture as well. The crosslinked blend membrane with 75wt% CS showed a highest total flux of 0.46 kg/m2/h and highest selectivity of 663 when operating at 70oC with 90wt% EG in the feed mixture.
Effects of crosslinking concentration and reaction time of trimesoyl chloride (TMC) were studied on poly(vinyl alcohol)-poly(sulfone) or PVA-PSf composite membranes. Results showed a consistent trend of changes in the physicochemical properties: the degree of crosslinking, crystallinity, surface roughness, hydrophilicity and swelling degree all decrease with increasing crosslinking agent (TMC) concentration and reaction time. The crosslinked membrane performance was assessed with PV dehydration of ethylene glycol-water mixtures at a range of concentrations (30 to 90wt% EG). The total flux of permeation was found to decrease, while the selectivity to increase, with increasing TMC concentration and reaction time. The decrease in flux was most prominent at low EG concentrations in the feed mixtures.
A central composite rotatable design (CCRD) of response surface methodology was used to analyze PV dehydration performance of crosslinked poly(vinyl alcohol) (PVA) membranes. Regression models were developed for the flux and selectivity as a function of operating conditions such as, temperature, feed alcohol concentration, and flow-rate. Dehydration experiments were performed on two different alcohol-water systems: isopropanol-water (IPA-water) and ethanol-water (Et-water) mixtures around the azeotrope concentrations. Judged by the lack-of-fit criterion, the analysis of variance (ANOVA) showed the regression model to be adequate. The predicted flux and selectivity from the regression models were presented in 3-D surface plots over the whole ranges of operating variables. For both alcohol-water systems, quadratic effect of temperature and feed alcohol concentration showed significant (p < 0.0001) influence on the flux and selectivity. A strong interaction effect of temperature and concentration was observed on the selectivity for the Et-water system. For the dehydration of azeotropic IPA-water mixture (87.5wt% IPA), the optimized dehydration variables were found to be 50.5oC and 93.7 L/hr for temperature and flow-rate, respectively. On the other hand for azeotropic Et-water mixture (95.5wt% Et), the optimized temperature and flow-rate were found to be 57oC and 89.2 L/hr, respectively. Compared with experiments performed at optimized temperature and feed flow-rate, the predicted flux and selectivity of the azeotropic mixtures showed errors to be within 3-6 %.
Conference papers on the topic "Central composite rotatable design (CCRD)"
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Gheith, Ramla, Fethi Aloui, and Sassi Ben Nasrallah. "Optimization of a Stirling Engine Performances: A Study Based on Experiments Design Approach." In ASME 2012 Fluids Engineering Division Summer Meeting collocated with the ASME 2012 Heat Transfer Summer Conference and the ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/fedsm2012-72239.
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The Stirling engine performances depend on several physicals characteristics and functioning parameters. The experimental design is an alternative to identify the parameters sets allowing optimal Stirling engine performances. So, a four factor Central Composite Rotatable Design (CCRD) was used to observe the effect of cooling water flowrate, initial charge pressure, heating temperature, and operation time on a Stirling engine brake power. The influence of each parameter and the effect of the interaction between two or three parameters on the engine performances are presented and analyzed. With modeling, optimal conditions for the Stirling engine functioning are the following: charge pressure of 8 bar, heating temperature of 500 °C and cooling water flow rates of 7.34 l/mn, independently of the engine operation time.
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Sivapirakasam, S. P., R. Anand, G. R. Kannan, and K. R. Balasubramanian. "Optimization of Biodiesel Production Using RSM and Study of Combustion Characteristics on DI Diesel Engine." In ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-86777.
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Biodiesel is a monoalkyl ester of fatty acid of long chain derived from vegetable oil or animal fats. In this present investigation deccan hemp oil, a non-edible vegetable oil is used as feed stock for the production of biodiesel. Response surface methodology based on Central Composite Rotatable Design (CCRD) is used to analyze the interaction effect and to optimize the transesterification reaction variables such as temperature, catalyst concentration and oil to methanol ratio on biodiesel yield. A quadratic model is developed based on the CCRD, correlating the yield of biodiesel with reaction variables. The predicted yield by optimization condition is found very close to the experimental values. The optimum condition for biodiesel production is found at the temperature of 55° C, oil to methanol ratio of 1:9, catalyst of 0.5%, stirring speed of 350 rpm and a reaction time of 3h gave the maximum yield of 95%. The physical and chemical properties of deccan hemp oil and its methyl ester is determined as per ASTM standards. The produced biodiesel showed shorter ignition delay of 10.5° CA and lower heat release rate when compared to diesel at full load condition.
3
Muralidharan, B., H. Chelladurai, and J. Ramkumar. "Experimental Investigation on Electro-Discharge Deposition Process." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-62866.
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The demand for multifunctional micro parts is an ever increasing need for product miniaturization. Amongst the spectrum of micro manufacturing processes, Electro-Discharge Deposition (EDD) is a newly developing additive process to produce parts in micro scale. In EDD the tool and workpiece electrodes are connected to reverse polarity in order to remove material from anode which deposits on cathode surface. The advantage of EDD is, any conducting tool material can be deposited irrespective of its hardness on the specified conducting substrate. So far, limited work has been carried out to develop micro parts like micro cylinders, micro spiral structures, etc., by EDD. In this work an attempt has been made to study the effect of various process parameters like current, duty cycle, pulse on time, voltage and table feed rate in EDD using central composite rotatable design (CCRD). It is found from the experimental results that, current plays a significant role in deposition of tool material.
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Das, Manas, V. K. Jain, and P. S. Ghoshdastidar. "Parametric Study of Process Parameters and Characterization of Surface Texture Using Rotational-Magnetorheological Abrasive Flow Finishing (R-MRAFF) Process." In ASME 2009 International Manufacturing Science and Engineering Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/msec2009-84320.
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In this paper an effort is made towards improving the performance of MRAFF process by providing a rotating magnetic field externally to the polishing medium by using permanent magnets in addition to the reciprocating motion provided to the polishing medium by a hydraulic unit. This finishing process creates a smooth mirror like finished surface with a few directional cutting marks (i.e. hatch pattern like honing) on the finished surface of stainless steel, brass, and EN-8 workpieces. Preliminary experimental study is conducted on MRAFF and rotational (R)-MRAFF processes to compare their process performance in terms of change in Ra (ΔRa) and change in material removal (ΔMR). Later complete experimental study of R-MRAFF process is carried out using central composite rotatable design (CCRD) and the responses are plotted using response surface methodology (RSM). Optimum finishing conditions are identified by optimization method developed by Derringer and Suich using Design-Expert® software. The present study shows that rotational speed of the magnet has significant effect on output response (%ΔRa). The finished surfaces are characterized in detail by atomic force micrographs (AFM), and scanning electron micrographs (SEM) to analyze the changes in surface generation at different RPM.
5
Fadzilah, R. Hanum, B. Arianto Sobhana, and M. Mahfud. "Central composite rotatable design for investigation of microwave-assisted extraction of ginger (Zingiber officinale)." In INTERNATIONAL CONFERENCE OF CHEMICAL AND MATERIAL ENGINEERING (ICCME) 2015: Green Technology for Sustainable Chemical Products and Processes. AIP Publishing LLC, 2015. http://dx.doi.org/10.1063/1.4938344.
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Pinto Ferreira Brasileiro, Pedro, Bruno Freitas, Darne Germano de Almeida, Rita de Cassia Freire Soares, Juliana Moura de Luna, Raquel Diniz Rufino, Valdemir Alexandre dos Santos, and Leonie Asfora Sarubbo. "SURFACE TENSION STUDY FROM THE BIOSURFACTANT PRODUCED BY Candida guilliermondii UTILIZING A CENTRAL COMPOSITE ROTATABLE DESIGN." In Simpósio Nacional de Bioprocessos e Simpósio de Hidrólise Enzimática de Biomassa. Campinas - SP, Brazil: Galoá, 2015. http://dx.doi.org/10.17648/sinaferm-2015-33717.
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Agrawal, Shyam S., and Sanjay Agarwal. "Study of Tool Wear in EDM Using Statistical Design of Experiments." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-67166.
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The tool wear, while machining a part in electric discharge machining (EDM) process, is of great concern in the researchers in recent years as the accuracy of tool wear directly affects the accuracy of the parts to be produced. The variation in tool wear may occur due to variation in the machining parameters such as current, spark gap, pulse duration, voltage, flushing of dielectric fluid, mode of flushing of dielectrics, taper angle of the tool, etc. This paper represents the effect of current, taper angle of tool and pulse duration on the tool wear during electrical discharge machining of EN-31 tool steel, as this is one of the materials being used increasingly in cold forming rolls, knurling tools, press tools, lathe centers, etc. The experiments have been conducted using “Central Composite Rotatable Design”. Results indicate that the tool wear could be reduced if machining is performed at low current values and low pulse duration and it could be further reduced with increase in the taper angle of tool.
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Kurozawa, Louise Emy, Gabriel Alves de Oliveira Scafi, and Renan Alex Lazarin. "Influence of process conditions on quality of spouted bed dried okara." In 21st International Drying Symposium. Valencia: Universitat Politècnica València, 2018. http://dx.doi.org/10.4995/ids2018.2018.7361.
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This study aimed to evaluate the spouted bed drying of okara with inert particles of polypropylene. A central composite rotatable design was carried out to verify the effect of drying air temperature and air flow on moisture content, techno-functional properties and trypsin inhibitors activity of dried product. Higher temperatures decreased emulsifying properties and trypsin inhibitor activity, probably due to thermal protein denaturation. In order to obtain a dried okara with maximum techno-functional properties and minimum moisture content and trypsin inhibitor activity, the optimal drying conditions were suggested: air temperature of 60ºC and air flow of 180 m3/h.Keywords: soy pulp; spouted bed drying; trypsin inhibitor activity; techno-functional properties; optimization
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Baraskar, S. S., and S. S. Banwait. "Application of Multiple Regression and Adaptive Neuro-Fuzzy Inference System for Prediction of Surface Roughness in EDM." In ASME 2012 International Manufacturing Science and Engineering Conference collocated with the 40th North American Manufacturing Research Conference and in participation with the International Conference on Tribology Materials and Processing. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/msec2012-7273.
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A manufacturing system is oriented towards higher production rate, better quality and reduced cost and time to make a product. Surface roughness is an index parameter for determining the quality of a machined product and is influenced by various input process parameters. Surface roughness prediction in Electrical Discharge Machine (EDM) is being attempted with many methodologies, yet there is a need to develop robust, autonomous and accurate predictive system. This work proposes the application of hybrid intelligent technique, multiple regression and adaptive neuro-fuzzy inference system (ANFIS) for prediction of surface roughness in EDM. An experimental data set is obtained with current, pulse-on time and pulse-off time as input parameters and surface roughness as output parameter. Central composite rotatable design was used to plan the experiments. Multiple regression model is developed using the experimental data, to generate additional input-output data set. The input-output data set is used for training and validation of the proposed technique. After validation, data are forwarded for prediction of surface roughness. The proposed hybrid model for the prediction of surface roughness has very good agreement with the experimental results.