Abstract: In this research, natural canthaxanthin as one of the
most important carotenoids was extracted from Dietzia
natronolimnaea HS-1. The changes of canthaxanthin enriched in oilin-
water emulsions with vegetable oil (5 mg/ 100 mL), Arabic gum (5
mg/100 mL), and potassium sorbate (0.5 g/100 mL) was investigated.
The effects of different pH (3, 5 and 7), as well as, time treatment (3,
18 and 33 days) in the environmental temperature (24°C) on the
degradation were studied by response surface methodology (RSM).
The Hunter values (L*, a*, and b*) and the concentration of
canthaxanthin (C, mg/L) illustrated more degradation of this pigment
at low pHs (pH≤ 4) by passing the time (days≥10) with R² 97.00%,
91.31%, 97.60%, and 99.54% for C, L*, a*, and b* respectively. The
predicted model were found to be significant (p
Abstract: The utilize of renewable energy sources becomes
more crucial and fascinatingly, wider application of renewable
energy devices at domestic, commercial and industrial levels is not
only affect to stronger awareness but also significantly installed
capacities. Moreover, biomass principally is in form of woods and
converts to be energy for using by humans for a long time.
Gasification is a process of conversion of solid carbonaceous fuel
into combustible gas by partial combustion. Many gasified models
have various operating conditions because the parameters kept in
each model are differentiated. This study applied the experimental
data including three inputs variables including biomass consumption;
temperature at combustion zone and ash discharge rate and gas flow
rate as only one output variable. In this paper, response surface
methods were applied for identification of the gasified system
equation suitable for experimental data. The result showed that linear
model gave superlative results.
Abstract: A mathematical model of the surface roughness
has been developed by using response surface methodology
(RSM) in grinding of AISI D2 cold work tool steels. Analysis
of variance (ANOVA) was used to check the validity of the
model. Low and high value for work speed and feed rate are
decided from design of experiment. The influences of all
machining parameters on surface roughness have been
analyzed based on the developed mathematical model. The
developed prediction equation shows that both the feed rate
and work speed are the most important factor that influences
the surface roughness. The surface roughness was found to be
the lowers with the used of low feed rate and low work speed.
Accuracy of the best model was proved with the testing data.