A step-by-step guide to non-linear regression analysis of experimental data using a Microsoft Excel spreadsheet

Curvas de secagem de banana passa foram determinadas, utilizando-se três temperaturas do ar de secagem. Os resultados indicaram que para reduzir o teor de umidade do produto até 23,5% foram necessários tempos de secagem de 51, 36 e 30 horas paras as temperaturas de 50, 60 e 70ºC, respectivamente. O modelo exponencial U/Uo = exp(-kt) foi ajustado para os dados experimentais mediante análise de regressão não-linear, encontrandose alto coeficiente de regressão linear. Determinou-se a atividade de água do produto ao longo do processo de secagem para as três temperaturas testadas. Estudou-se a correlação entre a atividade de água e o teor de umidade do produto, determinando-se as isotermas de dessorção da banana passa a 25ºC. Observou-se que a atividade de água diminuiu em função do tempo de secagem e do teor de umidade para as três temperaturas de secagem. Os dados experimentais foram ajustados mediante regressão não-linear ao modelo polinomial e a seguinte equação foi obtida: U = -1844,93 + 7293,53Aa 9515,52Aa2 + 4157,196Aa3. O ajuste mostrou-se satisfatório (R2 > 0,90). DRYING CURVES AND WATER ACTIVITY EVALUATION OF THE BANANA-PASSES Abstract Banana drying curves were determined by utilizing three drying air temperatures. The results indicated that to reduce the moisture content of the product until 23.5% it were necessary drying times of 51, 36 and 30 hours for temperatures of 50, 60 and 70ºC, respectively. The exponential model U/Uo = exp(-kt) was adjusted for the experimental data by means of non linear regression analysis, and a high coefficient of linear regression was found. The water activity of the product was determined throughout the drying process for the three tested temperatures. The correlation between the water activity and moisture content of the product was studied, and the sorption isotherms were determined at 25º C. It was observed that the water activity decreased in function to the drying time and moisture content for the three drying temperatures. The experimental data were adjusted by means of non linear regression to the polynomial model and the following equation was obtained: U = - 1844.93 + 7293.53A a 9515.52 Aa 2 + 4157.196A a 3. The final adjust was satisfactory (R2 > 0.90).

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EXPLORATION OF INTERCALATED KAOLINITE CLAY FOR THE UPTAKE OF BASIC DYE BY ADSORPTION − EQUILIBRIUM, KINETICS AND THERMODYNAMIC STUDIES

Journal of Chemical Society of Nigeria ◽

10.46602/jcsn.v46i1.590 ◽

2021 ◽

Vol 46 (1) ◽

Author(s):

C. E. Chigbundu ◽

K. O. Adebowale

Keyword(s):

Experimental Data ◽

Linear Regression ◽

Goodness Of Fit ◽

Linear Regression Analysis ◽

Dye Adsorption ◽

Batch Adsorption ◽

Sem Images ◽

Kaolinite Clay ◽

Non Linear ◽

The Impact

Dyes are complex and sensitive organic chemicals which exposes microbial populations, aquatic lives and other living organisms to its toxic effects if their presence in water bodies or industrial effluents are not properly handled. This work therefore, comparatively studied the adsorption efficiencies of natural raw kaolinite (NRK) clay adsorbent and dimethyl sulphoxide (DMSO) faciley intercalated kaolinite clay (DIK) adsorbent for batch adsorption of Basis Red 2 (BR2) dye. The impact of varying the contact time, temperature and other operating variables on adsorption was also considered. The two adsorbents were characterized using SEM images, FTIR and XRD patterns. Linear and non-linear regression analysis of different isotherm and kinetic models were used to describe the appropriate fits to the experimental data. Error analysis equations were also used to measure the goodness-of-fit. Langmuir isotherm model best described the adsorption as being monolayer on homogenous surfaces while Kinetic studies showed that Elovich model provides the best fit to experimental data. The adsorption capacities of NRK and DIK adsorbents for the uptake of BR2 were 16.30 mg/g and 32.81 mg/g, respectively (linear regression) and 19.30 mg/g and 30.81 mg/g, respectively (non-linear regression). The thermodynamic parameter, ∆G showed that BR2 dye adsorption onto the adsorbents were spontaneous. DIK adsorbent was twice efficient compared with NRK for the uptake of BR2 dye.

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Some applications of a digital computer program to estimate biological parameters by non-linear regression analysis

Biochimica et Biophysica Acta (BBA) - General Subjects ◽

10.1016/0304-4165(71)90143-7 ◽

1971 ◽

Vol 252 (3) ◽

pp. 421-426 ◽

Cited By ~ 14

Author(s):

G Atkins

Keyword(s):

Regression Analysis ◽

Linear Regression ◽

Computer Program ◽

Digital Computer ◽

Linear Regression Analysis ◽

Biological Parameters ◽

Non Linear

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Optimising the Production of Combined Filter/Sorption Composite Materials

International Polymer Science and Technology ◽

10.1177/0307174x1704400910 ◽

2017 ◽

Vol 44 (9) ◽

pp. 51-58

Author(s):

A.V. Genis ◽

A.V. Kuznetsov ◽

G.M. Il'yutkina ◽

L.V. Polyakov

Keyword(s):

Regression Analysis ◽

Composite Materials ◽

Linear Regression ◽

Protective Clothing ◽

Linear Regression Analysis ◽

Physicomechanical Properties ◽

Single Stage ◽

Service Properties ◽

Non Linear ◽

Bonding Technology

The main relationships governing the production of combined filter/sorption materials by plying-up with the application of adhesive melts have been studied. It has been established that the use of single-stage bonding technology makes it possible to improve the physical and physicomechanical properties of multilayer non-woven mats. The possibility of optimising the plying-up process by using multiple non-linear regression analysis has been demonstrated. Materials with service properties suitable for use in protective clothing have been obtained.

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