Journal articles: 'Central composite rotatable design (CCRD)'

1

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.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

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.

Full text

Abstract:

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.

APA, Harvard, Vancouver, ISO, and other styles

3

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.

Full text

Abstract:

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

APA, Harvard, Vancouver, ISO, and other styles

4

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.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

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.

Full text

Abstract:

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.

APA, Harvard, Vancouver, ISO, and other styles

6

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.

Full text

Abstract:

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.

APA, Harvard, Vancouver, ISO, and other styles

7

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.

Full text

Abstract:

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.

APA, Harvard, Vancouver, ISO, and other styles

8

Singh, Balbir, Sudhir Kumar, and Jatinder Kumar. "Multi-Objective Optimization in Electrical Discharge Machining of 6061 Al/SiC_pUsing RSM and NSGA-II." Key Engineering Materials 748 (August 2017): 207–11. http://dx.doi.org/10.4028/www.scientific.net/kem.748.207.

Full text

Abstract:

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.

APA, Harvard, Vancouver, ISO, and other styles

9

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.

Full text

Abstract:

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.

APA, Harvard, Vancouver, ISO, and other styles

10

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 text

APA, Harvard, Vancouver, ISO, and other styles

11

Singh, Ram Sarup, and Shveta Lotey. "Enhanced exoinulinase production from Kluyveromyces marxianus YS-1 using response surface methodology." Brazilian Archives of Biology and Technology 53, no. 5 (October 2010): 1005–13. http://dx.doi.org/10.1590/s1516-89132010000500002.

Full text

Abstract:

Optimization of critical medium components for exoinulinase production by Kluyveromyces marxianus YS-1 at shake-flask was investigated using response surface methodology (RSM) based on a central composite rotatable design (CCRD). A five-level with five factors CCRD was used to evaluate the influence of related factors including concentration of inulin, meat extract, calcium chloride, sodium dodecyl sulphate and medium pH. Optimum values obtained by RSM were 2% inulin, 2.17% meat extract, 0.65 mM calcium chloride, 0.10 mM sodium dodecyl sulphate and pH 5.5. Optimized medium projected a theoretical exoinulinase production of 63.61 IU/mL and biomass yield of 0.965 (OD600/10). Multiple correlation coefficient R was 0.9976 and 0.9605 for exoinulinase production and biomass yield, respectively, which being close to one, justified an excellent correlation between the predicted and experimental values. Maximum productivity of exoinulinase (64.05 IU/mL) obtained experimentally by RSM was more than double in comparison to earlier findings using classical one-variable-at-a-time technique.

APA, Harvard, Vancouver, ISO, and other styles

12

Li, Fang, Hongfang Ma, and Weiyong Ying. "Application of Response Surface Methodology and Central Composite Rotatable Design for Modeling and Optimization of Catalyst Compositions in Ethanol Synthesis via CO Hydrogenation." International Journal of Chemical Reactor Engineering 12, no. 1 (January 1, 2014): 245–55. http://dx.doi.org/10.1515/ijcre-2013-0156.

Full text

Abstract:

Abstract A statistical analysis about the effect of catalyst compositions on ethanol synthesis from CO hydrogenation was studied. The effect of Rh loading (0–3 wt.%), Fe loading (2–10 wt.%) and Mn loading (0.5–2.5 wt.%) of RhMnFe/γ-Al2O3 was studied through response surface methodology (RSM) combined with a central composite rotatable design (CCRD). A linear and a quadratic model were proposed to correlate the three variables to the two responses: CO conversion and ethanol selectivity. The predicted values for ethanol selectivity were in a good agreement with the experimental values, with R2 of 0.9779. The optimum conditions for achieving the maximum ethanol selectivity (27.8%) while limiting CO conversion at a moderate level (>20%) were as follows: Rh loading of 2.5 wt.%, Mn loading of 2.5 wt.% and Fe loading of 4 wt.%. Two representing catalysts were characterized by XRD, TPR and DRIFTS.

APA, Harvard, Vancouver, ISO, and other styles

13

Katoch, Sunain, Vinay Sharma, P. P. Kundu, and M. B. Bera. "Optimization of PET Glycolysis Process by Response Surface Methodological Approach: A Two-Component Modelling Using Glycolysis Time and Temperature." ISRN Polymer Science 2012 (March 21, 2012): 1–9. http://dx.doi.org/10.5402/2012/630642.

Full text

Abstract:

Response surface methodology (RSM) was used for predicting the optimal condition of glycolysis time and temperature in the recycling of PET scrap. Central composite rotatable design (CCRD) for two variables at four levels was chosen as the experimental design. The data obtained from measurement of properties were fitted as a two variable second-order equation and were plotted as 3D surface plots using programme developed in MATLAB v.5. Analysis of variance (ANOVA) was used to evaluate the validity of model. The optimum operating conditions for glycolysis time and temperature were 6.5 h and 180°C, respectively. Under these optimal conditions, the hydroxyl value and glycolysis conversion percentage was 38.14 mgKOH/g and 95%, respectively, at the 0.97 desirability level, whereas the acid value and number average molecular weight () at the same desirability level were 12.2 mgKOH/g and 695 g/mol, respectively.

APA, Harvard, Vancouver, ISO, and other styles

14

Poonia, Amrita, and Arti Kumari. "Development and Shelf-Life Evaluation of Functional Rabadi (A Fermented Pearl Millet Product) by Incorporation of Whey." Indian Journal of Nutrition and Dietetics 55, no. 3 (July 5, 2018): 318. http://dx.doi.org/10.21048/ijnd.2018.55.3.17874.

Full text

Abstract:

Rabadi, prepared by fermenting pearl millet (Pennisetum typhoideum L.) (PM) flour with buttermilk is a traditional popular beverage of North – Western states of India. A process for PM based Rabadi using fermented whey was attempted. Fermented whey and PM flour was mixed before fermentation and amount of flour, whey and temperature of fermentation were determined using Response Surface Methodology (RSM) with Central Composite Rotatable Design (CCRD). The product developed using 50 g PM flour, 660 ml fermented whey incubated at 37.5 oC temperature gave the most acceptable product on the basis of sensory evaluation. The standardized product was packed in indigenous pouches and stored at 4oC and 10 oC. The shelf life of the product was 8 days at 4 oC and 5 days at 10 oC respectively.

APA, Harvard, Vancouver, ISO, and other styles

15

Yasin, Yamin, Nur Syahirah Abdul Latif, and Abdul Hafiz Abdul Malik. "Response Surface Methodology as a Tool to Study the Removal of Amido Black Dye from Aqueous Solution using Anionic Clay Hydrotalcite." Scientific Research Journal 7, no. 1 (June 30, 2010): 51. http://dx.doi.org/10.24191/srj.v7i1.5011.

Full text

Abstract:

Anionic clay hydrotalcite was used as an adsorbent to remove amido black dye from aqueous solutions. Response surface methodology (RSM) based on a jive-level, four-variable Central Composite Rotatable Design (CCRD) was employedto evaluate the interactive effects ofvarious optimization parameters. The parameters were contact time (6-10 hrs), solution pH (4-8), adsorbent dosage (200-600 mg) and dye concentration (50-100 mg//). Simultaneously increasing contact time, initial concentration and amount ofadsorbent dosage increased the quantity ofamido black dye removed. The optimum conditions derived via RSM for the reaction were a reaction time of 8.48 hrs, a concentration of58.09 mg/l, an adsorbent dosage of431.24 mg/L anda solution pHof6.27. The experimental percentage removal was 85.55 % under optimum conditions, which compares well with the maximum predicted value of 87.95 %.

APA, Harvard, Vancouver, ISO, and other styles

16

Panneerselvam, Theivendren, Selvaraj Kunjiappan, Veerachamy Alagarsamy, Govindaraj Saravanan, and Pavadai Parasuraman. "Design, Optimization, Synthesis and AntiTB Screening of Benzimidazole Derivatives." Anti-Infective Agents 18, no. 1 (February 4, 2020): 24–42. http://dx.doi.org/10.2174/2211352517666190301144054.

Full text

Abstract:

Introduction: A biologically active benzimidazole synthesis was carried out at laboratory scale in order to reduce environmental pollution as well as to identify effective synthetic route. Methods: In this connection optimization was performed by Central Composite Rotatable Design (CCRD) to develop experimental data through Response Surface Methodology (RSM). The optimization of title analogue was performed by RSM which led us to the identification of high quality of synthetic yield. The effects of four independent parameters [1-5 mol of oxobutanoic acid (X1), 1-5 mol of thionyl chloride (X2), 1-5 mol of imidazol-2-yl-4-oxobutanoyl chloride (X3), and 1-5 mol of 4-nitro aniline (X4)] were taken into optimize the synthetic yields of title scaffold. Results and Conclusion: A result on randomly generated benchmark and real values such as percentage yield, λmax and Retention Time (RT) of title compound are found to be highly significant. The present model connected into maximizing percentage yield of title scaffold with developed optimal set. The high significant benzimidazole was screened for their MTB activity against MTB H37Ra strain by MABA screening.

APA, Harvard, Vancouver, ISO, and other styles

17

Nair, Keerthi G. S., Yamuna Ravikumar, Sathesh Kumar Sukumaran, and Ramaiyan Velmurugan. "Fabrication, Optimization and Characterization of Paclitaxel and Spirulina Loaded Nanoparticles for Enhanced Oral Bioavailability." Current Nanoscience 16, no. 5 (October 5, 2020): 723–33. http://dx.doi.org/10.2174/1573413716666200203115101.

Full text

Abstract:

Background: Paclitaxel and spirulina when administered as nanoparticles, are potentially useful. Methods: Nanoformualtions of Paclitaxel and Spirulina for gastric cancer were formulated and optimized with Central composite rotatable design (CCRD) using Response surface methodology (RSM). Results: The significant findings were the optimal formulation of polymer concentration 48 mg, surfactant concentration 45% and stirring time of 60 min gave rise to the EE of (98.12 ± 1.3)%, DL of (15.61 ± 1.9)%, mean diameter of (198 ± 4.7) nm. The release of paclitaxel and spirulina from the nanoparticle matrix at pH 6.2 was almost 45% and 80% in 5 h and 120 h, respectively. The oral bioavailability for the paclitaxel spirulina nanoparticles developed is 24.0% at 10 mg/kg paclitaxel dose, which is 10 times of that for oral pure paclitaxel. The results suggest that RSM-CCRD could efficiently be applied for the modeling of nanoparticles. The paclitaxel and spirulina release rate in the tumor cells may be higher than in normal cells. Paclitaxel spirulina nanoparticle formulation may have higher bioavailability and longer sustainable therapeutic time as compared with pure paclitaxel. Conclusion: Paclitaxel-Spirulina co-loaded nanoparticles could be effectively useful in gastric cancer as chemotherapeutic formulation.

APA, Harvard, Vancouver, ISO, and other styles

18

Carniel, Naira, Rogério Marcos Dallago, Denise Bilibio, Anderson Luiz Nunes, João Paulo Bender, and Wagner Luiz Priamo. "The effects of ultrasound-assisted extraction on polyphenolics compounds obtained from Physalis angulata using response surface approach." Acta Scientiarum. Technology 40, no. 1 (September 1, 2018): 35530. http://dx.doi.org/10.4025/actascitechnol.v40i1.35530.

Full text

Abstract:

Total polyphenols content (TPC), including flavonoids (rutin, mangiferin and kaempferol) and phenolic acids (gallic, caffeic and ellagic acid) from Physalis angulata were recovered by Ultrasound-Assisted Extraction and quantified by UV–vis and HPLC analysis. Process parameters were assessed through a Central Composite Rotatable Design (CCRD) and a model with regression coefficient equal to 0.9640, was used to establish the optimum conditions together with its respective response surfaces. The increase of ethanol percentage and solid-liquid ratio promoted a decrease on TPC but, on the other hand, the increase in the temperature led to an increase in the extraction of these compounds. Experimental results indicated a maximum amount of total polyphenols of 1.039 mg Gallic Acid Eqivalent (GAE) g-1 of extract, 104.88, 4.04, 8.37, 58.28, 13.26 and 1.87mg.L-1 for gallic acid, caffeic acid, ellagic acid, rutin, mangiferin and kaempferol, respectively.

APA, Harvard, Vancouver, ISO, and other styles

19

Yasin, Yamin, Nur Syahirah Abdul Latif, and Abdul Hafiz Abdul Malik. "Response Surface Methodology as a Tool to Study the Removal of Amido Black Dye from Aqueous Solution using Anionic Clay Hydrotalcite." Scientific Research Journal 7, no. 1 (June 1, 2010): 51. http://dx.doi.org/10.24191/srj.v7i1.9424.

Full text

Abstract:

Anionic clay hydrotalcite was used as an adsorbent to remove amido black dye from aqueous solutions. Response surface methodology (RSM) based on a five-level, four-variable Central Composite Rotatable Design (CCRD) was employed to evaluate the interactive effects of various optimization parameters. The parameters were contact time (6-10 hrs), solution pH (4-8), adsorbent dosage (200-600 mg) and dye concentration (50-100 mg/I). Simultaneously increasing contact time, initial concentration and amount of adsorbent dosage increased the quantity of amido black dye removed. The optimum conditions derived via RSM for the reaction were a reaction time of 8.48 hrs, a concentration of 58. 09 mg/I, an adsorbent dosage of 431. 2 4 mg/L and a solution pH of 6.27. The experimental percentage removal was 85.55 % under optimum conditions, which compares well with the maximum predicted value of 87.95 %.

APA, Harvard, Vancouver, ISO, and other styles

20

TOMULESCU, CATERINA, MIȘU MOSCOVICI, ROXANA MĂDĂLINA STOICA, GABRIEL BUJOR ALBU, CLAUDIA SEVCENCO, and ADRIAN VAMANU. "Optimization and kinetics studies on exopolysaccharide production using Klebsiella oxytoca ICCF 419 strain, and glucose as substrate." Romanian Biotechnological Letters 26, no. 1 (January 1, 2021): 2214–22. http://dx.doi.org/10.25083/rbl/26.1/2214.2222.

Full text

Abstract:

The present work aimed to investigate the efficiency of kinetic modeling and Response Surface Methodology (RSM), by employing a Central Composite Rotatable Design (CCRD) and to evaluate the effects of carbon and nitrogen sources, inoculation volume, and bioprocess time on an exopolysaccharide (EPS) producer, Klebsiella oxytoca ICCF 419, in batch fermentation with shaken flasks. Among the kinetic models tested, logistic equations were found to fit accordingly, with a correlation coefficient (R2 ) of 0.999. The interaction between glucose and corn steep liquor was found to have a significant impact on the EPS production, and glucose (2% w/v), and a 5% v/v inoculum of 24 hours age, are sufficiently to positively affect the bioprocess, if it is desired only a maximum cell growth, but not associated with the polymer synthesis. The optimal formula predicted by the RSM design was experimentally validated by the following results: 12.16 g EPS/L and 1.65 dry biomass/L, after 48 hours fermentation.

APA, Harvard, Vancouver, ISO, and other styles

21

Mehra, Vinayak, Varun Gupta, and Pradeep Khanna. "MATHEMATICAL MODELLING TO PREDICT ANGULAR DISTORTION IN MIG WELDING OF STAINLESS STEEL 202 PLATES." Journal of Production Engineering 23, no. 2 (December 30, 2020): 16–20. http://dx.doi.org/10.24867/jpe-2020-02-016.

Full text

Abstract:

In present research, mathematical models have been established to predict the angular distortion in Metal Inert Gas(MIG) welding for 6mm plates of SS 202 grade for butt welded joints. The filler metal used was a continuously fed solid metal wire of stainless steel (304L).100% Argon gas was used to serve the purpose of shielding the weld pool from the atmosphere as it does not dissociate at high temperatures. This prevented any turbulence in the welding arc and deterioration in weld quality. To obtain experimental samples, the design matrix was developed using the statistical technique of central composite rotatable design (CCRD). Analysis of Variance (ANOVA) technique was used for the adequacy check of the models developed. The models developed can be used to find direct and interaction effect of the input parameters, namely welding speed (WS), voltage (V), nozzle to plate distance (NPD), torch angle (Ɵ) and wire feed rate (WFR) on the angular distortion.

APA, Harvard, Vancouver, ISO, and other styles

22

Roy, Subha M., Mohammad Tanveer, C. K. Mukherjee, and B. C. Mal. "Design characteristics of perforated tray aerator." Water Supply 20, no. 5 (April 20, 2020): 1643–52. http://dx.doi.org/10.2166/ws.2020.069.

Full text

Abstract:

Abstract The performance of the perforated tray aerator (PTA) was evaluated by conducting experiments in a tank of size 4 m × 4 m × 1.5 m. Based on the dimensional analysis, non-dimensional numbers related to geometric variables, viz. numbers of trays (n), ratio of consecutive width of tray to total height of aerator , ratio of perforation diameter to total height of aerator and ratio of the volume of water in the tank to total height of aerator were developed. Experiments were conducted with different numbers of trays (n): 1, 2, 3 and 4, keeping = 0.33, = 2.5 × 10−4, = 2,500 and pump flow rate (Q) = 0.010 m3/s as constants. The optimum number of perforated trays was found to be 3. Response surface methodology (RSM) and central composite rotatable design (CCRD) were used to further optimize the geometric variables with combinations of non-dimensional geometric variables , and . The flow rate (Q) of 0.013 m3/s and number of trays (n) as 3 were kept as constants. The optimum performance of PTA was obtained at = 0.665, = 1.85 × 10−4 and = 312.50 with the maximum non-dimensional standard aeration efficiency (NDSAE) and standard aeration efficiency (SAE) of 35.58 × 10−3 and 1.45 kgO2/kWh.

APA, Harvard, Vancouver, ISO, and other styles

23

Paiva, José E. de, Iriani R. Maldonade, and Adilma R. P. Scamparini. "Xylose production from sugarcane bagasse by surface response methodology." Revista Brasileira de Engenharia Agrícola e Ambiental 13, no. 1 (February 2009): 75–80. http://dx.doi.org/10.1590/s1415-43662009000100011.

Full text

Abstract:

The aim of this study was to optimize the production of xylose from sugarcane bagasse. The hydrolysis process was carried out to evaluate the effect of temperature and sulphuric acid concentration on the xylose production at 18, 30, and 50 min of hydrolysis. A Central Composite Rotatable Design (CCRD) was used to study two process variables, temperature (111.5; 114.0; 120.0; 126.0 and 128.5 ºC) and sulphuric acid concentration (0.20; 0.70; 1.90; 3.10 and 3.60% v v-1). Sulphuric acid had a greater influence on the hydrolysis process than temperature. At concentrations of sulphuric acid higher than 3.10% (v v-1), raising temperature had little influence on the yield of xylose production. The best condition to obtain xylose (266.73 mg g-1 of dry bagasse) was at 18 min of reaction, at 126 ºC and 3.10% (v v-1) of sulphuric acid, representing 96.0% of the theoretical maximum.

APA, Harvard, Vancouver, ISO, and other styles

24

Gupta, A. K., A. K. Jha, and S. Singhal. "Optimisation of modification parameters for amaranth starch for the development of pudding and study of the quality traits of developed pudding." Acta Alimentaria 50, no. 1 (March 5, 2021): 22–32. http://dx.doi.org/10.1556/066.2020.00110.

Full text

Abstract:

AbstractAmaranth is considered to be a part of “superfood”, however, due to multiple restricting properties, its functionality in the food industry is still not explored to its fullest. The present study investigated the effect of almond gum concentration (3–10 g), temperature (50–90 °C), and quantity of water (30–70 mL) on the functional properties of amaranth starch. A central composite rotatable design (CCRD) showed that the 6.9 g of almond gum, 64.43 mL of water, and temperature maintained at 90 °C, were the optimised conditions to attain 16.77 g g−1 of swelling power, 12.97% of solubility index, and 20.13% freeze-thaw stability. Moreover, the modified amaranth starch was further employed to develop pudding as a value-added product. The findings concluded that the developed pudding using modified amaranth starch exhibited enhanced sensorial attributes due to an increase in cohesiveness, chewiness, and resilience of starch gel.

APA, Harvard, Vancouver, ISO, and other styles

25

Siepmann, Francieli Begnini, Daneysa Lahis Kalschne, Caroline Zabotti, Eder Lisandro de Moraes Flores, Cristiane Canan, and Eliane Colla. "Feasibility of bioethanol production from rice bran." Semina: Ciências Agrárias 41, no. 6supl2 (November 6, 2020): 2951–66. http://dx.doi.org/10.5433/1679-0359.2020v41n6supl2p2951.

Full text

Abstract:

Rice bran is a by-product of rice production with a high carbohydrate and starch content and the potential for bioethanol production by alcoholic fermentation. This article describes bioethanol production by Saccharomyces cerevisiae from hydrolyzed defatted rice bran (DRB) a rice by-product applying ultrasonic treatment and protease addition, as well as a sequential strategy of experimental design (SEED). In the first Central Composite Rotatable Design (CCRD), the temperature (25-30 °C) and inoculum concentration (0.5-50 g L-1) had positive effects on bioethanol production, while the effect of pH (4.0-6.0) was not significant. In the second CCRD, the temperature (28-35 °C) and inoculum concentration (10-70 g L-1) had negative and positive effects on bioethanol production (p < 0.05). Protease addition (15 µL g-1) increased the conversion of substrate into bioethanol by 76%. The optimized conditions for the production of 40.7 g L-1 bioethanol were a temperature of 31.5 °C and an inoculum concentration of 70 g L-1. Validation in a benchtop bioreactor produced 40.0 g L-1 of bioethanol from hydrolyzed DRB, and the SEED was characterized as a useful tool to improve bioethanol production from DRB. Furthermore, the DRB proved to be a by-product with great potential for bioethanol production, derived from alternative sources not commonly used in human food.

APA, Harvard, Vancouver, ISO, and other styles

26

Malinowska, Eliza, Wojciech Krzyczkowski, Grzegorz Łapienis, and Franciszek Herold. "Improved simultaneous production of mycelial biomass and polysaccharides by submerged culture of Hericium erinaceum: optimization using a central composite rotatable design (CCRD)." Journal of Industrial Microbiology & Biotechnology 36, no. 12 (September 27, 2009): 1513–27. http://dx.doi.org/10.1007/s10295-009-0640-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Idris, Mohamad Shahrul Fizree, Nur Hanis Adila Azhar, Fazira Firdaus, Siti Efliza Ashari, and Siti Fairus Mohd Yusoff. "Effect of Temperature, Time and Diimide/Rubber Ratio on the Hydrogenation of Liquid Natural Rubber by Response Surface Methodology." Indonesian Journal of Chemistry 19, no. 4 (August 13, 2019): 882. http://dx.doi.org/10.22146/ijc.36706.

Full text

Abstract:

Hydrogenated liquid natural rubber (HLNR) was synthesized from liquid natural rubber (LNR) by thermolysis of p-toluenesulfonyl hydrazide (TSH). The HLNR structure was characterized by Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies. Thermogravimetric analysis (TGA) showed that the HLNR had higher decomposition temperature compared to LNR. A response surface methodology (RSM) based on a central composite rotatable design (CCRD) with five-level-three-factors was used to optimize the main important reaction parameters, such as the TSH:LNR weight ratio (1–3), reaction temperature (110–150 °C), and reaction time (1–8 h). A quadratic model was developed using this multivariate statistical analysis. Optimum conditions for the non-catalytic hydrogenation of LNR using TSH were obtained; an LNR hydrogenation percentage of 83.47% at a TSH:LNR weight ratio of 1.41, a reaction temperature of 118.11 °C, and a reaction time of 3.84 h were predicted. The R2 value of 0.9949 indicates that the model provides data that are well matched with those from the experiment.

APA, Harvard, Vancouver, ISO, and other styles

28

Silva, Cassio Nazareno Silva da, Maria Carolina Bezerra Di-Medeiros, Luciano Morais Lião, Kátia Flávia Fernandes, and Karla de Aleluia Batista. "Cashew Gum Polysaccharide Nanoparticles Grafted with Polypropylene Glycol as Carriers for Diclofenac Sodium." Materials 14, no. 9 (April 22, 2021): 2115. http://dx.doi.org/10.3390/ma14092115.

Full text

Abstract:

This investigation focuses on the development and optimization of cashew gum polysaccharide (CGP) nanoparticles grafted with polypropylene glycol (PPG) as carriers for diclofenac sodium. The optimization of parameters affecting nanoparticles formulation was performed using a central composite rotatable design (CCRD). It was demonstrated that the best formulation was achieved when 10 mg of CGP was mixed with 10 μL of PPG and homogenized at 22,000 rpm for 15 min. The physicochemical characterization evidenced that diclofenac was efficiently entrapped, as increases in the thermal stability of the drug were observed. The CGP-PPG@diclofenac nanoparticles showed a globular shape, with smooth surfaces, a hydrodynamic diameter around 275 nm, a polydispersity index (PDI) of 0.342, and a zeta potential of −5.98 mV. The kinetic studies evidenced that diclofenac release followed an anomalous transport mechanism, with a sustained release up to 68 h. These results indicated that CGP-PPG nanoparticles are an effective material for the loading/release of drugs with similar structures to diclofenac sodium.

APA, Harvard, Vancouver, ISO, and other styles

29

Devi, Sheetal, Dipendra Kumar Mahato, Sarvesh Singh, and Surendra Prasad Singh. "Optimization of Process Variables for Retention of Functional Properties of Bitter Melon (Momordica Charantia L.) and its Shelf-Life Extension." Current Agriculture Research Journal 7, no. 1 (April 23, 2019): 74–89. http://dx.doi.org/10.12944/carj.7.1.10.

Full text

Abstract:

This study was carried out to investigate the effect of sodium hypochlorite (NaClO), hydrogen peroxide (H2O2) and soaking time on vitamin C, carotenoid, antioxidant activity and total phenolic content for optimizing the pre-treatment for minimal processing of bitter melon slices and to evaluate its shelf life at different storage conditions. Fresh-cut bitter melon slices were given post-cutting treatment of wash solution containing NaClO(25-500ppm) and H2O2 (1-5%) solution for different time intervals (10-120 minutes). The treated samples were analyzed for Vitamin C content, carotenoid, DPPH inhibition activity, ABTS inhibition activity and total phenolic content (TPC) using Central Composite Rotatable Design (CCRD). The optimum condition for soaking achieved by CCRD was NaClO (25 ppm), H2O2 (1%) and soaking time (56.32 min). The minimally processed bitter melon at optimized wash water treatment was packed in LDPE pouch of 0.1 mm thickness and were evaluated for shelf-life under modified atmospheric packaging, MAP 1 (5% O2, 25% CO2 & 70% N2) and MAP 2(10% O2, 20% CO2 & 70% N2) stored at temperature of 5, 20 and 35°C, respectively. Based on the microbiological, colour and textural analysis, MAP 1 was found to be better compared to MAP 2 and the shelf-life of fresh-cut bitter melon slices was prolonged up to twenty-eight days of storage.

APA, Harvard, Vancouver, ISO, and other styles

30

Ambhore, Nitin, Dinesh Kamble, and Satish Chinchanikar. "Analysis of tool vibration and surface roughness with tool wear progression in hard turning: An experimental and statistical approach." Journal of Mechanical Engineering and Sciences 14, no. 1 (March 23, 2020): 6461–72. http://dx.doi.org/10.15282/jmes.14.1.2020.21.0506.

Full text

Abstract:

The machined surface quality and dimensional accuracy obtained during hard turning is prominently gets affected due to tool wear and cutting tool vibrations. With this view, the results of tool wear progression on surface quality and acceleration amplitude is presented while machining AISI 52100 hard steel. Central Composite Rotatable Design (CCRD) is employed to develop experimental plan. The results reported that vibration signals sensed in a tangential direction (Vz) are most sensitive and found higher than the vibrations in the feed direction (Vx) and depth of cut direction (Vy). The acceleration signals in all three directions are observed to increase with the advancement of tool wear and good surface finish is observed as tool wear progresses up-to 0.136mm. The vibration amplitude is discovered high in the range 3 kHz – 10 kHz within selected cutting parameter range (cutting speed 60-180mm/min, feed 0.1-0.5mm/rev, depth of cut 0.1-0.5mm). The investigation is extended for the development of multiple regression models with regression coefficients value 0.9. These models found statically significant and give dependable estimates between a tool vibrations and cutting parameters.

APA, Harvard, Vancouver, ISO, and other styles

31

Oluwabukola Belinda Aturu, Joshua Olanrewaju Olaoye, Agidi Gbabo, Ibrahim Mohammed Gana, Ndudi Efomah Andrew, and Jacob Tizhe Liberty. "Effect of shelling speed, moisture content and number of beaters on the cleaning and recovery efficiency of a mechanized centrifugal Melon shelling machine." World Journal of Advanced Research and Reviews 10, no. 3 (June 30, 2021): 239–45. http://dx.doi.org/10.30574/wjarr.2021.10.3.0229.

Full text

Abstract:

A response surface methodology (RSM) has been utilized for investigating the effects of the speed of shelling, melon seed moisture content and the number of beaters of a developed mechanized centrifugal melon shelling and cleaning machine. The machine shells the melon and then cleans the shelled seed from the shells and other impurities. The experiment was based on a central composite rotatable design (CCRD). The results of the experiments revealed that the highest shelling efficiency of 88.5% was obtained from a combination of a speed of 2300 rpm, moisture content of 15% (w.b) and 20 beaters, while the least efficiency of 25.11% was obtained from an interaction between a speed of 959 rpm, moisture content of 20% (w.b) and 18 beaters. Numerical optimization carried out with the goal of maximizing the shelling efficiency revealed optimum values of speed of 2200 rpm, moisture content of 12% (w.b) and 19 beaters for shelling efficiency of 88.80%. The result of this study provided standard input parameters capable of yielding high cleaning and recovery efficiency.

APA, Harvard, Vancouver, ISO, and other styles

32

Yasin, Yamin, Mohd Najif Ab Rahman, Zaini Hamzah, and Ahmad Saat. "Application of Response Surface Methodology for Optimization of Copper Removal from Aqueous Solution Using Magnesium Aluminium Hydrogenphosphate Layered Double Hydroxides." Advanced Materials Research 832 (November 2013): 622–27. http://dx.doi.org/10.4028/www.scientific.net/amr.832.622.

Full text

Abstract:

Magnesium-aluminium hydrogenphosphate layered double hydroxide that synthesized by used of co-precipitation and followed by hydrothermal (MAHP4) method was used as an adsorbent to remove copper ions from aqueous solutions. The effects of various optimization parameters such as contact time, adsorbent dosage and lead ion concentrations were investigated by used of Response surface methodology (RSM). The Response surface methodology (RSM) based on a four-level-three variables Central Composite Rotatable Design (CCRD) was employed to evaluate the interactive effects of the various optimization parameters. The parameters were contact time (2-6 h), adsorbent dosage (0.01 0.05 g) and copper ion concentrations (50 100 mg/l). Simultaneously by increasing contact time and amount of dosage of MAHP4 used, the percentage of lead ion removal from aqueous solution was increased. However, the percentage removal decreases with an increase in concentrations of copper ion. The experimental percentage removal recorded under optimum conditions was compared well with the maximum predicted value from the RSM which suggest that fractional factorial design of RSM can be used to study the removal of copper from aqueous solution by used of magnesium-aluminium hydrogenphosphate layered double hydroxide as an adsorbent.

APA, Harvard, Vancouver, ISO, and other styles

33

Singh, Dixita, Abhishek D. Tripathi, Kundan S. Adhikari, and Veena Paul. "Development of Functional Dark Chocolate by Incorporating Flaxseed (Linum usitatissimum) Oil and Honey with Improved Organoleptic and Textural Attributes." Current Nutrition & Food Science 16, no. 5 (July 14, 2020): 698–708. http://dx.doi.org/10.2174/1573401315666190823093846.

Full text

Abstract:

Background: Chocolate is one of the most consumable fast-moving consumer goods (FMCG), possessing many health benefits. The present study was envisaged to develop dark chocolate incorporated with flaxseed (Linum usitatissimum) oil and honey. Flaxseed oil contains omega-3 fatty acid which is useful in heart disease, arthritis, inflammatory and autoimmune diseases, and cancer, whereas honey acts as an antioxidant. Objective: The objective of this study was to develop functional dark chocolate with improved organoleptic, textural and functional attributes by optimizing the ingredients levels such as flaxseed oil and honey and its further validation for quality improvement. Methods: The chocolate composition was optimized by selecting two variables including flaxseed oil (1-2.5g) and honey (10-15g) at 3 levels in central composite rotatable design (CCRD) by using Design- Expert version 11 software tool. Results: After optimization, the best-predicted formulation comprising flaxseed oil 2.37% (w/w) and honey 15% (w/w) showed best sensorial score (p<0.05) with desirability 0.826. Conclusion: Physicochemical analysis of optimized formulation showed significant improvement in organoleptic attributes (p <0.05) with a significant increase of 10.22% (p <0.05) in antioxidant activity in comparison to control.

APA, Harvard, Vancouver, ISO, and other styles

34

Kumar, Rajeev, Somnath Chattopadhyaya, G. K. Singh, and Umesh Kumar Vates. "Modeling and Spark Erosion Drilling Process Optimization of Inconel 718 Using RSM Technique." Journal of Advanced Manufacturing Systems 18, no. 01 (February 13, 2019): 57–83. http://dx.doi.org/10.1142/s0219686719500033.

Full text

Abstract:

Electrical discharge machining with rotary tool is known as electric discharge drilling (EDD) which is being widely used for machining the difficult-to-cut materials like super alloy, ceramics and composite materials. Present research work has been introduced to find the impact of four influencing input factors discharge current (C), pulse off time ([Formula: see text]), pulse-on time ([Formula: see text]) and drill speed (S) on the response, tool wear rate (TWR), metal removal rate (MRR) and Centre line average value of surface roughness (Ra). The spark erosion drilling was performed on the Inconel 718 with rotating copper electrode. The major performances characteristics material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR) are to be evaluated with consultation of Response Surface Methodology (RSM) techniques. The central composite rotatable design (CCRD) has been reported to plan the experimental design and developing the model for prediction of data within the range of investigation. ANOVA test was also carried out to check the adequacy for development of models. It has been evaluated that discharge current, [Formula: see text], and [Formula: see text] have been found as most significant factors that effects on the performance measures. The models have 86.02, 84.29, and 83.15% values of correlation coefficient (R2) for MRR, TWR and Ra whereas the adjusted R2 (R2 adj) are 73.80%, 70.55%, and 68.41% for MRR, TWR and SR, respectively.

APA, Harvard, Vancouver, ISO, and other styles

35

Senthivelan, T., J. Kanagaraj, Rames C. Panda, and T. Narayani. "Screening and production of a potential extracellular fungal laccase from Penicillium chrysogenum: Media optimization by response surface methodology (RSM) and central composite rotatable design (CCRD)." Biotechnology Reports 23 (September 2019): e00344. http://dx.doi.org/10.1016/j.btre.2019.e00344.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Silva, Jezica P. P., Antonio M. C. Rodrigues, and Luiza H. M. Silva. "Aqueous Enzymatic Extraction of Buriti (Mauritia Flexuosa) Oil: Yield and Antioxidant Compounds." Open Food Science Journal 11, no. 1 (February 28, 2019): 9–17. http://dx.doi.org/10.2174/1874256401911010009.

Full text

Abstract:

Introduction: Enzyme-assisted aqueous extraction is considered an emerging green technique that has been applied to different oilseeds. Objective: This study aimed to study the enzymatic aqueous extraction process of buriti oil using a central composite rotatable design (CCRD) combined with the response surface methodology aiming to obtain higher yield and antioxidant compounds in the oil. Methods: The study was carried out in two steps. The first assessed the efficiency of different enzymes (cellulase, pectinase, and protease) and the variables of greater influence in the extraction process, being conducted for each enzyme a CCRD design. The second step was carried out with the enzyme that showed the best performance on the extraction yield, changing the experimental bands of the variables that had greater significance in the first step, with the goal of broadening the spectrum of study. Were also evaluated in this step, total carotenoids, total phenolic compounds, and the antioxidant capacity of the oils extracted. Results: In the first experiment, cellulase gave the highest yield, while the most significant variables were temperature and time. For the second design, performed with cellulase, were defined as optimal operating conditions at 55 °C temperature, 2% enzyme concentration and 6 hours extraction. For these conditions, the yield obtained was 76.5%, with total carotenoid concentration of 3,119.5 µg β-carotene.g-1. Analysis of variance was performed and showed the significance of the regression and non-significance of the lack-of-fit (p<0.05). The coefficients of determination of the yield and carotenoid content were 95.6% and 94.5%, respectively. The highest value of total phenolic compounds determined for buriti oil in this study was 254 ± 5 µg GAE.g-1 oil, while for the antioxidant capacity was 218.0 ± 0.3 µmol Trolox.g-1 oil. Conclusion: The enzymatic aqueous extraction process is viable for buriti oil and produced oils with high concentrations of antioxidant compounds.

APA, Harvard, Vancouver, ISO, and other styles

37

Issa, Hayder Mohammed. "Retracted: Prediction and optimization of volumetric power draw in an aerated and stirred vessel used in wastewater biological plant: a mathematical model developed by using central composite rotatable design analysis (CCRD)." Water Practice and Technology 11, no. 3 (September 1, 2016): 590–600. http://dx.doi.org/10.2166/wpt.2016.064.

Full text

Abstract:

In this study, the volumetric power draw P/V was determined as a factor in designing and identifying the optimal condition a successful aeration for stirred wastewater biological treatment vessels. The study was performed to characterize the volumetric power draw in the aerated stirred vessels by optimizing the operation variables. The concerning factors were improved by conjugating stirring and aeration with efficient and economic volumetric power draw condition. The drawn volumetric power was tested and analyzed for three independent parameters; impellers rotation speed (100–200 rpm), turbine blades submergence ratio S/W (0.33–1.67) and wastewater height level ratio H/D (1.37–1.58). A mathematical model was developed in the form of a nonlinear polynomial mathematical model to predict the P/V. The optimal values of the P/V and of relevant parameters were computed through the application of the Box–Wilson technique by application of the central composite rotatable design (CCRD) model. The volumetric power draw P/V and the relevant independent parameters are presented in optimal conditions surface plots that obtained from the nonlinear mathematical model. Optimum analysis result for the independent parameters showed low levels of impellers rotation speed and turbine submergence ratio draw lower P/V while wastewater height did not have a clear effect on P/V.

APA, Harvard, Vancouver, ISO, and other styles

38

Gharibzahedi, S. M. T., S. H. Razavi, and M. Mousavi. "Enzymatically hydrolysed molasses and sodium citrate as new potentials for the improvement of canthaxanthin batch synthesis by Dietzia natronolimnaea HS-1: A statistical media optimisation ." Czech Journal of Food Sciences 32, No. 4 (July 29, 2014): 326–36. http://dx.doi.org/10.17221/472/2013-cjfs.

Full text

Abstract:

Response surface methodology-central composite rotatable design (RSM-CCRD) was applied to explore the optimum media formulation for maximising canthaxanthin (CTX) biosynthesis by Dietzia natronolimnaea HS-1. The effects of three variables of enzymatically hydrolysed molasses (EHM) (16.6–33.4 g/l), sodium (Na)-citrate (21.64–28.36mM), and yeast extract (6.32–9.68 g/l) concentrations on the production of CTX, total carotenoid (TCT), and biomass dry weight (BDW) were appraised. The results showed that the quadratic effects of EHM, yeast extract, and Na-citrate contents in terms of second-order polynomial regression equations (R<sup>2 </sup>= 0.968–0.986), respectively, had the most significant effects on the produced TCT and CTX. The predicted maximum accumulation of BDW (8.88 g/l), TCT (7.24 mg/l), and CTX (6.40 mg/l) under the optimum concentrations of the media variables (26.16 g/l EHM, 8.29 g/l yeast extract, and 25.86mM Na-citrate) was very close to the experimental values determined in batch experiments. The high BDW content suggested EHM and Na-citrate as very promising feedstocks for CTX bioproduction by the bacterium studied.

APA, Harvard, Vancouver, ISO, and other styles

39

Kato, H. C. A., L. F. H. Lourenço, E. A. F. Araújo, C. L. Sousa, M. R. S. Peixoto Joele, and S. C. A. Ribeiro. "Change in physical and chemical characteristics related to the binomial time-temperature used in sous pasteurization see Tambaqui (Colossoma macropomum)." Arquivo Brasileiro de Medicina Veterinária e Zootecnia 68, no. 1 (February 2016): 224–32. http://dx.doi.org/10.1590/1678-4162-8096.

Full text

Abstract:

The goal of this study was to evaluate sous vide fish and assess the influence of time and temperature on the pasteurization process through quality parameters. The raw material (tambaqui fillets) and the sous vide underwent physical, physicochemical, and microbiological analyses. A sauce was prepared containing soy sauce, water, horseradish and garlic flakes. The product's pasteurization parameters of time and temperature were defined according to a 22 central composite rotatable design (CCRD), and the dependent variables were water holding capacity (WHC) and instrumental texture aiming at obtaining high WHC values for the product to maintain the desired juiciness. The microbiological analysis required by legislation have indicated that the fish fillets and sous vide were within de standard. The values of total coliforms found in the samples (fillets and sous vide) analyzed were below the critical level of 10² CFU/g. The counts of sulphite-reducing clostridia and psychrotrophic and mesophilic bacteria on plates in the samples were <1x10 CFU/g. In conclusion, temperature was the most important factor in the pasteurization process, significantly contributing to the quality of the final product. The mathematical models proposed were considered predictive for each response.

APA, Harvard, Vancouver, ISO, and other styles

40

Yusof, Nurul Atikah Amin, Nursyamsyila Mat Hadzir, Siti Efliza Ashari, Nor Suhaila Mohamad Hanapi, and Rossuriati Dol Hamid. "Optimization of Enzymatic Synthesis of Betulinic Acid Amide in Organic Solvent by Response Surface Methodology (RSM)." Indonesian Journal of Chemistry 19, no. 4 (August 13, 2019): 849. http://dx.doi.org/10.22146/ijc.34903.

Full text

Abstract:

Optimization of the lipase catalyzed enzymatic synthesis of betulinic acid amide in the presence of immobilized lipase, Novozym 435 from Candida antartica as a biocatalyst was studied. Response surface methodology (RSM) and 5-level-4-factor central-composite rotatable design (CCRD) were employed to evaluate the effects of the synthesis parameters, such as reaction time (20–36 h), reaction temperature (37–45 °C), substrate molar ratio of betulinic acid to butylamine (1:1–1:3), and enzyme amounts (80–120 mg) on the percentage yield of betulinic acid amide by direct amidation reaction. The optimum conditions for synthesis were: reaction time of 28 h 33 min, reaction temperature of 42.92 °C, substrate molar ratio of 1:2.21, and enzyme amount of 97.77 mg. The percentage yield of actual experimental values obtained 65.09% which compared well with the maximum predicted value of 67.23%. The obtained amide was characterized by GC, GCMS and 13C NMR. Betulinic acid amide (BAA) showed a better cytotoxicity compared to betulinic acid as the concentration inhibited 50% of the cell growth (IC50) against MDA-MB-231 cell line (IC50 < 30 µg/mL).

APA, Harvard, Vancouver, ISO, and other styles

41

Zanette, Jéssica C., Márcia T. Veit, Gilberto C. Gonçalves, Soraya M. Palácio, Fernando R. Scremin, Alex S. Torquato, and Márcia R. S. A. Vieira. "A study on the removal of prednisone from aqueous solutions by adsorption onto a vegetal activated carbon." Water Science and Technology 78, no. 11 (December 17, 2018): 2328–37. http://dx.doi.org/10.2166/wst.2018.515.

Full text

Abstract:

Abstract This study evaluated the prednisone removal from aqueous solutions using adsorption by an activated carbon of vegetal origin (VAC). A central composite rotatable design (CCRD) and the response surface methodology (RSM) were used to verify the influence of the parameters: pH, adsorbent dose and prednisone concentration in a batch adsorption process. Among the analyzed parameters, only the adsorbent dose and the prednisone concentration were statistically significant (α = 0.05) and the critical values obtained were adsorbent dose: 1.87 g/L, pH 7.56 and prednisone concentration: 3.66 mg/L with 77.51% of prednisone removal by VAC. The kinetic study of the adsorption of prednisone reached the equilibrium in 4 h. The pseudo-first-order model described adequately the kinetics data behavior. The equilibrium experimental data obtained at different temperatures showed that the VAC has a maximum adsorption capacity of 18.04 mg/g at a temperature of 30 °C. The prednisone removal decreased by the increasing temperature and the Langmuir isotherm well described the experimental data (R² > 0.98). Thermodynamic results shown that the prednisone removal of aqueous solutions by VAC is spontaneous and favorable process.

APA, Harvard, Vancouver, ISO, and other styles

42

Zohourkari, Iman, Mehdi Zohoor, and Massimiliano Annoni. "Investigation of the Effects of Machining Parameters on Material Removal Rate in Abrasive Waterjet Turning." Advances in Mechanical Engineering 6 (January 1, 2014): 624203. http://dx.doi.org/10.1155/2014/624203.

Full text

Abstract:

The effects of the main operational machining parameters on the material removal rate (MRR) in abrasive waterjet turning (AWJT) are presented in this paper using a statistical approach. The five most common machining parameters such as water pressure, abrasive mass flow rate, cutting head traverse speed, workpiece rotational speed, and depth of cut have been put into a five-level central composite rotatable experimental design (CCRD). The main effects of parameters and the interaction among them were analyzed by means of the analysis of variance (ANOVA) and the response surfaces for MRR were obtained fitting a second-order polynomial function. It has been found that depth of cut and cutting head traverse speed are the most influential parameters, whereas the rotational speed is insignificant. In addition, the investigations show that interactions between traverse speed and pressure, abrasive mass flow rate and depth of cut, and pressure and depth of cut are significant on MRR. This result advances the AWJT state of the art. A complete model discussion has been reported drawing interesting considerations on the AWJT process characterising phenomena, where parameters interactions play a fundamental role.

APA, Harvard, Vancouver, ISO, and other styles

43

Meng, Dong Dong, Tao Jiang, Hui Xia Liu, Xiao Wang, and Yan Wei Wu. "Experimental Study on Laser Transmission Joining between PA66GF and AISI304." Key Engineering Materials 667 (October 2015): 54–61. http://dx.doi.org/10.4028/www.scientific.net/kem.667.54.

Full text

Abstract:

Joining between polyamides (PA) and metals has potential applications in the industry. Based on PA66GF and AISI304, the experimental study of laser transmission joining of the dissimilar materials is conducted in this article. Firstly, comprehensive experiments of laser transmission joining between PA66GF and AISI304 are carried out by Nd: YAG pulsed laser source according to the central composite rotatable design method (CCRD). Secondly, the effects of the process parameters like voltage, joining speed and stand-off distance on the joint quality are analyzed by response surface methodology (RSM). Finally, mathematical models between the process parameters and the lap-shear strength and the joint width are established and based on which, the optimization of the joining process is done and the optimized results are predicted. The results show that the process parameters of laser transmission joining play a significant role in determining the joint quality; the predicted data of the models are in good agreement with the experimental results and can be of great help for the optimization of the joining process. As a result, this study could provide an effective instruction about how to choose the reasonable process parameters for enhancing the joining efficiency.

APA, Harvard, Vancouver, ISO, and other styles

44

Bogdanovic, Aleksandra, Vanja Tadic, Slobodan Petrovic, and Dejan Skala. "Supercritical CO2 extraction of steroidal sapogenins from fenugreek (Trigonella foenum-graecum L.)seed." Chemical Industry and Chemical Engineering Quarterly 26, no. 2 (2020): 171–82. http://dx.doi.org/10.2298/ciceq191001036b.

Full text

Abstract:

Supercritical CO2 extraction was applied on fenugreek (Trigonella foenum-graecum L., Fabaceae) seeds with the aim to define optimal process conditions to obtain the maximal extract yields content of steroidal sapogenins. Central composite rotatable design (CCRD) combined with response surface methodology (RSM) was applied to determine optimal process conditions defined by the influence and interaction of pressure, temperature and time of extraction through consumption of SC CO2. Optimization experiments revealed that the pressure of 24.73 MPa, the temperature of 38.?C and the consumption of SC CO2 of 19.24 g/gDM were the best process conditions enabling the maximal yield of extract and gain of the highest content of sapogenins. The optimal values of pressure and temperature defined SC CO2 density of 885.47 kg/m3, which provided the maximal yield of the extract with the highest content of steroidal sapogenins. The achieved yield of extract at these conditions was 0.073g/gDM, with 0.774 mg/gDM diosgenin, 0.477 mg/gDM protodioscin, 0.713 mg/gDM sarsapogenin and 0.205 mg/gDM oleanolic and ursolic acid with a significant quantity of 2.475 mg/gDM in the obtained extract.

APA, Harvard, Vancouver, ISO, and other styles

45

Ibrahim, Salis, Regina Santos, and Steve Bowra. "Optimisation of Organic Solvent Mediated Solubilisation of Apple Pomace Polyphenolic Compounds Using Response Surface Methodologies." International Journal of Chemistry 11, no. 2 (May 8, 2019): 1. http://dx.doi.org/10.5539/ijc.v11n2p1.

Full text

Abstract:

Polyphenolic compounds extraction from industrial apple pomace was optimised by applying design of experiments (DoE) and surface response methodology using the Central Composite Rotatable Design (CCRD). The degree solubilisation and the yield of total phenolic content from the apple pomace using organic solvents was shown to be influenced by process parameters including solvent type, solvent concentration, temperature, apple pomace to solvent ratio, and extraction time (residency time). Optimal conditions of extracting phenolic compounds were as follows: acetone concentration, 65 % (v/v); solid to solvent ratio 1 %; extraction time 30 minutes and temperature 60oC. Optimum condition for solubilisation was as follows: acetone concentration 78 % (v/v); solid to solvent ratio 4.7 %; extraction time 54 minutes and temperature 21oC. Under these conditions, the total phenolic content and solubilisation were 21.70 ± 0.2 mg GAE/g dw and 19.20 ± 0.1g/100g of the dried apple pomace respectively and largely agreed with those predicted by the Stat-Ease software. Independent variables for optimisation of total phenolic content and solubilisation were completely different. The reverse phase HPLC analysis of the extract revealed the major polyphenolic compounds were chlorogenic acid, procyanidin B2, caffeic acid, epicatechin, ferulic acid, quercetin-3-galactoside, quercetin-3-glucoside and phloridzin.

APA, Harvard, Vancouver, ISO, and other styles

46

Imtiaz, Abid, Adnan Tariq, Ajaz Bashir Janjua, Fahad Sarfraz, and Amar ul Hassan Khawaja. "Parametric Optimization of Butt Welded Polycarbonate using Response Surface Methodology." January 2021 40, no. 1 (January 1, 2021): 38–52. http://dx.doi.org/10.22581/muet1982.2101.04.

Full text

Abstract:

Friction Stir Welding (FSW) is a solid-state joining process for metals, non-metals and polymers. It is carried out with the help of a specially designed, non-consumable tool. The heat required, for creating a softened region at the faying surfaces, is generated by rotation of tool against the work piece material. Being a solid-state welding process, it offers several advantages like inducing minimum effect on the mechanical properties of base material, reduced shrinkage and distortion, no spatter or Ultra Violet (UV) radiations etc. However, developing a sound weld requires an appropriate combination of several process parameters e.g. the design of tool, its rotational and traversing speeds etc. To substantiate this aspect, an approach based on Response Surface Methodology (RSM) is presented during this paper that optimizes the combination of process parameters while investigating their effect on the mechanical properties of a friction stir welded butt joint configuration of Polycarbonate. To minimize the total number of combinations a Central Composite Rotatable Design (CCRD) is used with three factors and two levels. The results have shown that the butt joints fabricated at a traverse speed of 14 mm/min, rotational speed of 1700 RPM and with simple cylindrical conical tool geometry yielded the maximum ultimate tensile strength of 51.299 MPa.

APA, Harvard, Vancouver, ISO, and other styles

47

Anschau, Andréia, Katira da Mota Huerta, Tatiane Vieira Rêgo, Janaina Mardioni Gonçalves de Oliveira, Carina Molins Borba, Susana Juliano Kalil, Carlos André Veiga Burkert, and Janaína Fernandes de Medeiros Burkert. "Enzymatic synthesis optimization of isoamyl butyrate from fusel oil." Acta Scientiarum. Biological Sciences 43 (April 20, 2021): e54966. http://dx.doi.org/10.4025/actascibiolsci.v43i1.54966.

Full text

Abstract:

Many food, cosmetic and pharmaceutical industries have increased their interest in short-chain esters due to their flavor properties. From the industrial standpoint, enzyme reactions are the most economical strategy to reach green products with neither toxicity nor damage to human health. Isoamyl butyrate (pear flavor) was synthesized by isoamyl alcohol (a byproduct of alcohol production) and butyric acid with the use of the immobilized lipase Lipozyme TL IM and hexane as solvents. Reaction variables (temperature, butyric acid concentration, isoamyl alcohol:butyric acid molar ratio and enzyme concentration) were investigated in ester conversion (%), concentration (mol L-1) and productivity (mmol ester g-1 mixture . h), by applying a sequential strategy of the Fractional Factorial Design (FFD) and the Central Composite Rotatable Design (CCRD). High isoamyl butyrate conversion of 95.8% was achieved at 24 hours. At 3 hours, the highest isoamyl butyrate concentration (1.64 mol L-1) and productivity (0.19 mmol ester g-1 mixture . h) were obtained under different reaction conditions. Due to high specificity and selectivity of lipases, process parameters of this study and their interaction with the Lipozyme TL IM are fundamental to understand and optimize the system so as to achieve maximum yield to scale up. Results show that fusel oil may be recycled by the green chemistry process proposed by this study.

APA, Harvard, Vancouver, ISO, and other styles

48

Knezevic-Jugovic, Zorica, Dejan Bezbradica, Zivana Jakovljevic, Suzana Brankovic-Dimitrijevic, and Dusan Mijin. "Lipase catalyzed synthesis of flavor esters in non-aqueous media: Optimization of the yield of pentyl 2-methylpropanoate by statistical analysis." Journal of the Serbian Chemical Society 73, no. 12 (2008): 1139–51. http://dx.doi.org/10.2298/jsc0812139k.

Full text

Abstract:

In this study, the synthesis of pentyl 2-methylpropanoate employing a commercial lipase from Candida rugosa was investigated, the emphasis being placed on analyzing the effects of various process conditions on the yield of ester. The response surface methodology (RSM) and five-level-five-factor central composite rotatable design (CCRD) were used to evaluate the effects of variables, namely the initial water content, 0.0-2.0% (w/v), the reaction temperature, 35-75?C, the enzyme concentration, 1.0-5.0 g dm-3, the acid/alcohol mole ratio, 1:2-5:2, and the reaction time, 4-48 h, on the yield (%) of ester. The production of pentyl 2-methylpropanoate was optimized and an ester yield response equation was obtained, enabling the prediction of ester yields from known values of the five main factors. It seems that the enzyme concentration, reaction time and acid/alcohol mole ratio predominantly determine the conversion process, while the amount of added water amount had no significant influence on the ester yield. Conversion of around 92 % of the substrate to ester could be realized using a concentration of lipase as low as 4.0 g dm-3 and in a relatively short time (26 h) at 35?C, when a high substrate mole ratio of 2.5 was used.

APA, Harvard, Vancouver, ISO, and other styles

49

Leś, Karolina, Karol Kowalski, and Ireneusz Opaliński. "Optimisation Of Process Parameters In High Energy Mixing As A Method Of Cohesive Powder Flowability Improvement." Chemical and Process Engineering 36, no. 4 (December 1, 2015): 449–60. http://dx.doi.org/10.1515/cpe-2015-0032.

Full text

Abstract:

Abstract Flowability of fine, highly cohesive calcium carbonate powder was improved using high energy mixing (dry coating) method consisting in coating of CaCO3 particles with a small amount of Aerosil nanoparticles in a planetary ball mill. As measures of flowability the angle of repose and compressibility index were used. As process variables the mixing speed, mixing time, and the amount of Aerosil and amount of isopropanol were chosen. To obtain optimal values of the process variables, a Response Surface Methodology (RSM) based on Central Composite Rotatable Design (CCRD) was applied. To match the RSM requirements it was necessary to perform a total of 31 experimental tests needed to complete mathematical model equations. The equations that are second-order response functions representing the angle of repose and compressibility index were expressed as functions of all the process variables. Predicted values of the responses were found to be in a good agreement with experimental values. The models were presented as 3-D response surface plots from which the optimal values of the process variables could be correctly assigned. The proposed, mechanochemical method of powder treatment coupled with response surface methodology is a new, effective approach to flowability of cohesive powder improvement and powder processing optimisation.

APA, Harvard, Vancouver, ISO, and other styles

50

Kim, Min-Suk, Namin Koo, Jeong-Gyu Kim, and Sang-Hwan Lee. "Effects of Washing Solution, Washing Time, and Solid-Solution Rate on the Maximum Heavy Metals Removal Efficiency." Applied Sciences 11, no. 14 (July 11, 2021): 6398. http://dx.doi.org/10.3390/app11146398.

Full text

Abstract:

In Korea, for heavy metal-contaminated soil, there are insufficient basic data as well as field application cases for soil washing. This study was conducted to suggest the significant factors and optimal operation conditions for the maximum heavy metal removal efficiency. Five types of washing solution [acid solution (HCl), citric acid, oxalic acid, EDTA, and CaCl2], washing time (10–360 min), and solid-solution ratio (1:2–1:100) were selected as significant operational factors. Non-observed effect concentration (NOEC) and central composite rotatable design (CCRD) were applied to derive the optimal conditions. The soil pH was slightly alkali, and it was highly contaminated by Cd (17.34 mg kg−1), Cu (307.76 mg kg−1), Pb (714.78 mg kg−1), and Zn (1755.47 mg kg−1), complexly. For all heavy metals, CaCl2, a neutral salt, was difficult to achieve the remediation goal. On the other hand, Cd, Cu, and Pb were removed successfully from the soil by acid solution, citric acid, oxalic acid, and EDTA. For Zn, only acid solution and oxalic acid could meet the remediation goal (300 mg kg−1). As the washing time increased, the heavy metal removal efficiency showed a tendency to increase overall. Especially, oxalic acid and acid solution were able to reach the highest efficiency point within 30 min, whereas citric acid and EDTA took 2 to 4 h at the longest. In the case of 1 M citric acid, through the CCRD experiment, optimal operation conditions (solid-solution ratio and washing time) could be deduced for each heavy metal. Furthermore, this series of processes can be utilized as a useful tool to find the optimal operating conditions and, at the same time, achieve the remediation goal.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Central composite rotatable design (CCRD)'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles