Full factorial design to assess the concrete gas permeability

Novel composite material durability is mainly affectedby the transport of fluids and ions through thepore system which are potentially able to producedamage. Then, a key indicator of long-term durabilityof the structures can be the ease with which aggressiveagents are transported through the pore system,i.e. composite material permeability. The purpose ofthis paper is to broaden our knowledge of air permeabilitytesting conditions and, in particular, how it isaffected by the preconditioning temperature and testingpressure. Optimization of variables to determinatethe air permeability coefficient was done by using a 23full factorial design. Air permeability results are recordedin ∅150x70 mm3 concrete specimens. The airpermeability determination procedure gives reliableinformation about the quality of concrete with regardto its durability

Recycling chips of stainless steel using a full factorial design

The aim of this study was to provide an experimental investigation on the novel method for recycling chips of duplex stainless steel, with the addition of vanadium carbide, in order to produce metal/carbide composites from a high-energy mechanical milling process. Powders of duplex stainless steel with the addition of vanadium carbide were prepared by high-energy mechanical ball milling utilizing a planetary ball mill. For this proposal, experiments following a full factorial design with two replicates were planned, performed, and then analyzed. The four factors investigated in this study were rotation speed, milling time, powder to ball weight ratio and carbide percentage. For each factor, the experiments were conducted into two levels so that the internal behavior among them could be statistically estimated: 250 to 350 rpm for rotation speed, 10 to 50 h for milling time, 10:1 to 22:1 for powder to ball weight ratio, and 0 to 3% carbide percentage. In order to measure and characterize particle size, we utilized the analysis of particle size and a scanning electron microscopy. The results showed with the addition of carbide in the milling process cause an average of reduction in particle size when compared with the material without carbide added. All the four factors investigated in this study presented significant influence on the milling process of duplex stainless steel chips and the reduction of particle size. The statistical analysis showed that the addition of carbide in the process is the most influential factor, followed by the milling time, rotation speed and powder to ball weight ratio. Significant interaction effects among these factors were also identified98CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAIS - FAPEMIGsem informaçãosem informaçãosem informaçã

Parametric study via full factorial design for glycerol supercritical gasification

International audienceSupercritical water gasification is a promising technology for pollution treatment and syngas pro- duction from biomass. The produced gas is composed of hydrogen, carbon dioxide, methane, car- bon monoxide and traces of ethane and other light hydrocarbons. This work aims to give a comprehensive experimental study of the supercritical water gasification of glycerol using a full factorial design of experiments (DOE). The effect of five factors, namely: temperature [458°C–542°C], residence time [40–90min], pressure [23–27MPa], initial concentration of glycerol [10–19wt%] and KOH catalyst quantity [0.60–1.475wt%], were investigated on several responses such as the gasification efficiency (GE), syngas composition and lower calorific value (LCV) of the produced gas. First order mathematical models correlating each considered response in terms of the considered factors were developed and validated. Also, the significance of the factors effect was validated using analysis of variance. The results showed that the produced gas composition and quality were strongly influenced by temperature and initial concentration. The largest gas pro- duction was detected at a temperature of 542°C, a residence time of 40min, a pressure of 27MPa, a concentration of 10 wt% glycerol and a KOH catalyst percentage of 1.475 wt%

Statistically designed experiments to screen chemical mixtures for possible interactions.

For the accurate analysis of possible interactive effects of chemicals in a defined mixture, statistical designs are necessary to develop clear and manageable experiments. For instance, factorial designs have been successfully used to detect two-factor interactions. Particularly useful for this purpose are fractionated factorial designs, requiring only a fraction of all possible combinations of a full factorial design. Once the potential interaction has been detected with a fractionated design, a more accurate analysis can be performed for the particular binary mixtures to ensure and characterize these interactions. In this paper this approach is illustrated using an in vitro cytotoxicity assay to detect the presence of mixtures of Fusarium mycotoxins in contaminated food samples. We have investigated interactions between five mycotoxin species (Trichothecenes, Fumonisins, and Zearalenone) using the DNA synthesis inhibition assay in L929 fibroblasts. First, a central composite design was applied to identify possible interactive effects between mycotoxins in the mixtures (27 combinations from 5(5) possible combinations). Then two-factor interactions of particular interest were further analyzed by the use of a full factorial design (5 x 5 design) to characterize the nature of those interactions more precisely. Results show that combined exposure to several classes of mycotoxins generally results in effect addition with a few minor exceptions indicating synergistic interactions. In general, the nature of the interactions characterized in the full factorial design was similar to the nature of those observed in the central composite design. However, the magnitude of interaction was relatively small in the full factorial design

A 32 FULL FACTORIAL DESIGN FOR TOPICAL CONTROLLED RELEASETAZAROTENE MICROSPONGE USING HPMC GEL

Objective: The aim of present work was to the development of control release 0.1% tazarotene microsponge and incorporated into a HPMC K-100M gel. Methods: Drug compatibility with polymer was evaluated by FT-IR spectrum. Tazarotene microsponge was prepared by quasi-emulsion solvent diffusion method. On the basis of preliminary results, 32 full factorial design was employed to study the effect of Eudragit RS-100 conc. (X1) and PVA conc. (X2) on as particle size (Y1), % drug entrapment (Y2) and time required to 80% drug release (Y3). Multiple linear regression analysis, ANOVA and graphical representation of the influence factor by 3D plots were performed by using Sigma plot 11.0. In this study, the following constraints were arbitrarily used for the selection of an optimized batch: particle size<200 µm, drug entrapment>70 %, and time required to 80% drug release>360 min. The optimized formulation was subjected to SEM study. Tazarotene microsponge incorporates in 3% HPMC K-100M gel evaluated for viscosity, pH, drug content, spreadability, In vitro diffusion study, release kinetic study and photostability study. Results: The FT-IR result showed that there was no chemical interaction and SEM photograph indicates that microsponges are spherical and pores. From the results of multiple regression analysis, it was found that all factors had a statistically significant influence on all dependent variables. Conclusion: The optimized formulation of gel release kinetics having good linearity (R2= 0.987) of zero-order kinetic and it was found to be stable in the stability evaluation

Subcritical water extraction (SWE) of Zingiber zerumbet using two level full factorial design

Zingiber zerumbet was reported to has chemo preventive effects and was suggested as one of the therapeutic treatments for cancer. In this study, Z. zerumbet was extracted using subcritical water extraction (SWE) by employing two level full factorial design. 2k full factorial design was employed using 18 runs with 10 repeats in central points. The independent variables factors were temperature (100-150°C), time (10-30 minutes) and material ratio (1:10 and 1:20 g/ml) for the evaluation of highest zerumbone concentration and overall yield of extracted Z. zerumbet. Effects of extraction temperature and time were found to be significant on all responses with p-value <0.05. However, the material ratio only gave significant effect on the zerumbone concentration and less significant on the yield. In addition, the value of curvature was found to be significant, thus indicating the relation between the independent variables and the response was linear. Therefore, it was found that the concentration of zerumbone and yield from Z. zerumbet extracted by SWE were significantly affected by temperature and time of extraction

OPTIMIZATION OF AQUEOUS-BASED FILM COATING PROCESS PARAMETERS CONTAINING GLUCOSAMINE SULFATE POTASSIUM CHLORIDE

Objective: The aim of the present work was to prepare film coated tablet of glucosamine sulfate potassium chloride and study the effect of coating process parameters which implicate more significant effects on an aqueous-based film coating process of tablets. Methods: The different batches of uncoated tablets were prepared by wet granulation method. Aqueous film coating was carried out by using opadry®II white 85F18422. A 32 full factorial design was employed to study the effect of spray rate (X1) and inlet air temperature (X2) on coating uniformity, coating process efficiency and % loss on drying. The surface characteristics of the aqueous based film coated tablet were studied using a SEM. Check point batch was prepared to validate the evolved model. Results: Preliminary trials indicated that individually process parameters affected the quality of coated tablets. Hence, studied the combined effect of these factors on the coating process required and 32 full factorial design was applied. In this study, it was seen that spray rate and inlet air temperature had a major effect on tablet coating process. It was observed from factorial batch that maximum drug release was found in batch F5. Conclusion: The results of full factorial design indicate both parameters spray rate (X1) and inlet air temperature (X2) have significant effect on coating process and batch F5 is stable for 3 mo at accelerated condition

Optimizing mating schemes in fish breeding

The optimal contribution selection method and the simulated annealing algorithm were used to maximize the genetic gain and reduce inbreeding in fish breeding populations. This study considered the following mating designs: full factorial (3 x 3); full factorial (6 x 6) and nested (6 males x 18 females). A quantitative trait based on a strictly additive and polygenic model was simulated. Two levels for the number of genotyped offspring (360 or 720) and three levels of heritability (0.1; 0.3; 0.5) were assumed. The best results in terms of DF and DG were obtained with the full factorial design (6 x 6) and considering a trait with a high heritability. The optimal family size was found at 20 fish per mating

Optimization of a Novel Oral Colon Delivery System of Indomethacin Using Full Factorial Design

Purpose: To develop and optimize indomethacin (IDM) matrix tablets for specific colon drug delivery.Methods: Indomethacin matrix tablets containing hydrogenated castor oil (HCO), and pectin (PEC) were prepared by hot fusion method. A 32 full factorial design was used to investigate the combined effect of two independent formulation variables, X1 and X2, namely, the amount of HCO and PEC, respectively. Their effect on IDM release from the matrix tablets in acidic medium (0.1 N HCl) and phosphate buffer (pH 6.8), were analyzed and optimized. A contour plot was also applied to graphically represent the effect of the independent variables on drug release in pH 6.8 medium at 2 h (Y1) and 24 h (Y2), and the time required for 25 % drug release (Y3) as dependent variables.Results: The optimized IDM matrix tablets showed almost total retardation of drug release in acidic medium and prolonged sustained release in pH 6.8 medium over 24 h. The correlation coefficient (R2) value for Y1, Y2 and Y3 were 0.99850, 0.9980 and 0.9970, respectively, indicating good correlation between dependent and independent variables. Differences between the coefficients for Y1, Y2 and Y3 were significant (p &lt; 0.05), and hence contributed significantly to the prediction of the independent variables.Conclusion: The findings indicate that successful design, development, and optimization of IDM matrix tablets for colon delivery has been achieved.Keywords: Indomethacin, Hydrogenated castor oil, Pectin, Factorial design, Matrix tablets, Colondelivery syste