scholarly journals A Mathematical Model for the Alkylation of Phenol with Octanol-1

2012 ◽  
Vol 60 (1) ◽  
pp. 65-70
Author(s):  
Manoranjan Saha ◽  
Md Kabir Hossain ◽  
Md Ashaduzzaman ◽  
Dipti Saha ◽  
Shams Tania Afroza Islam ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Sulphuric Acid ◽  
Molar Ratio ◽  
Suggested Model ◽  
Stirring Time ◽  
Experimental Yield ◽  
The Difference ◽  
Main Effects ◽  
Factor Interaction ◽  
Three Factor

A 3-factor 2-level Yates pattern experimental design was used to develop a mathematical model for the alkylation of phenol with octanol-1 in the presence of sulphuric acid. A set of trials was planned with two replicates and the centre point trial with 4 replicates. Main effects as well as two- and three- factor interaction effects were statistically significant. The highest experimental yield was 79.5%. The experimental settings were temperature, 160ºC; molar ratio of phenol to octanol-1, 10:1; amount of 94% sulphuric acid, 8% by wt. of phenol; addition time, 2h and stirring time, 2h. Adequacy of the suggested model was checked. The difference between the experimental and estimated yield was negligible.DOI: http://dx.doi.org/10.3329/dujs.v60i1.10339  Dhaka Univ. J. Sci. 60(1): 65-70 2012 (January)

scholarly journals A Mathematical Model for the Alkylation of o-Cresol with Cyclohexanol

1970 ◽  
Vol 44 (2) ◽  
pp. 181-186
Author(s):  
M Ashaduzzaman ◽  
Manoranjan Saha ◽  
Shams Tania Afroza Islam ◽  
Mohammad Ismail ◽  
Nashid Sharif ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Experimental Design ◽  
Perchloric Acid ◽  
Molar Ratio ◽  
Suggested Model ◽  
Critical Response ◽  
Stirring Time ◽  
Main Effects ◽  
Factor Interaction ◽  
Three Factor

A mathematical model was developed for the alkylation of o-cresol with cyclohexanol in the presence of perchloric acid as a catalyst. A set of trials was planned according to a 3 factor 2-level Yates pattern experimental design. The variables chosen for the study were temperature, molar ratio of o-cresol to cyclohexanol and amount of perchloric acid. The critical response was the yield of cyclohexyl o-cresol. Main effects as well as two-and three-factor interaction effects were statistically significant. The adequacy of the suggested model was checked up. The highest experimentally found yield was 89.3% while the estimated yield was found to be 89.09%. The experimentally settings were temperature, 140O C; molar ratio of o-cresol to cyclohexanol, 6:1; amount of catalyst, 5% by wt. of o-cresol; addition time, 2 h; stirring time, 1 h. Keywords: o-Cresol, Cyclohexanol, Experimental design, Alkylation. DOI: 10.3329/bjsir.v44i2.3669 Bangladesh J. Sci. Ind. Res. 44(2), 181-186, 2009

scholarly journals Application of Statistical Experimental Design to Benzylation of p-Chlorophenol

1970 ◽  
Vol 45 (2) ◽  
pp. 105-110 ◽  
Author(s):  
Shams Tania Afroza Islam ◽  
Manoranjan Saha ◽  
Dipti Saha ◽  
Mohammad Ismail ◽  
Mirza Galib ◽  
...  
Keyword(s):  
Experimental Design ◽  
Benzyl Alcohol ◽  
Perchloric Acid ◽  
Molar Ratio ◽  
Statistical Experimental Design ◽  
Stirring Time ◽  
Experimental Yield ◽  
The Difference ◽  
Main Effects ◽  
Factor Interaction

A 23 Yates pattern experimental design was used to develop a mathematical model for the benzylation of p-chlorophenol with benzyl alcohol in the presence of perchloric acid as catalyst. A set of trials was planned with two replicates and the centre point trial with 4 replicates according to the design. The critical response was the yield of 2-benzyl-4-chlorophenol. Main effects as well as two- and three- factor interaction effects were statistically significant. The highest experimental yield was 91.6%. The experimental settings were 130°C, molar ratio of p-chlorophenol to benzyl alcohol 4:1, amount of 60% perchloric acid 5% by wt. of p-chlorophenol, addition time 2 h and stirring time 1 h. The difference between the experimental and predicted yields did not exceed 0.04%.Key words: p-Chlorophenol; Benzyl alcohol; Perchloric acid; 2-benzyl-4-chlorophenol; Experimental design DOI: 10.3329/bjsir.v45i2.5706Bangladesh J. Sci. Ind. Res. 45(2), 105-110, 2010

scholarly journals Application of plackett-burman design to benzylation of o-cresol with benzyl alcohol

2015 ◽  
Vol 50 (3) ◽  
pp. 169-180
Author(s):  
M Shahruzzaman ◽  
D Saha ◽  
MS Rahman ◽  
MS Rahman
Keyword(s):  
Benzyl Alcohol ◽  
Aluminium Chloride ◽  
Molar Ratio ◽  
Critical Response ◽  
Stirring Time ◽  
Anhydrous Alcl3 ◽  
Burman Design ◽  
Main Effects ◽  
Plackett Burman Design ◽  
Factor Interaction

Plackett-Burman design was employed to study the reaction of o-cresol with benzyl alcohol in the presence of anhydrous aluminium chloride as catalyst for screening variables. The variables chosen for the investigation were temperature, molar ratio of o-cresol to benzyl alcohol, amount of anhydrous AlCl3 catalyst (% by wt. of o-cresol), addition time (ta h), stirring time (ts h), stirring speed (rpm). Among these variables temperature, molar ratio of o-cresol to benzyl alcohol and amount of anhydrous AlCl3 were found to be important. A set of trials was planned according to a 3 factor 2-level Yates pattern experimental design with 2 replicates and the center point trial with 4 replicates. The critical response was the yield of benzyl o-cresol. Main effects as well as two- and three- factor interaction effects were statistically significant. A polynomial model was developed and the adequacy of the suggested model was checked up.Bangladesh J. Sci. Ind. Res. 50(3), 169-180, 2015

scholarly journals Alkylation of Ethylbenzene with Cyclohexylchloride: A Statistical Study

2012 ◽  
Vol 60 (1) ◽  
pp. 71-76
Author(s):  
Manoranjan Saha ◽  
Prashanta Chakravarty ◽  
Dipti Saha ◽  
Md Zahangir Alam ◽  
Mahmud Hasan Tareque ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Experimental Design ◽  
Interaction Effect ◽  
Statistical Study ◽  
Aluminium Chloride ◽  
Molar Ratio ◽  
Suggested Model ◽  
Anhydrous Aluminium Chloride ◽  
Critical Response ◽  
Main Effects

A mathematical model was developed for the alkylation of ethylbenzene with cyclohexyl chloride in the presence of anhydrous aluminium chloride as a catalyst using the Yates Pattern experimental design. The variables chosen for the study were temperature, molar ratio of ethylbenzene to cyclohexyl choloride and amount of anhydrous aluminium chloride. The critical response was the yield of cyclohexylethylbenzene. Main effects as well as interaction effect of molar ratio of ethylbenzene to cyclohexyl chloride and amount of catalyst were statistically significant. The adequacy of the suggested model was checked.DOI: http://dx.doi.org/10.3329/dujs.v60i1.10340  Dhaka Univ. J. Sci. 60(1): 71-76 2012 (January)

scholarly journals Evaluation of a Mathematical Model for Digital Image Enhancement

2015 ◽  
Vol 9 (1) ◽  
pp. 292-296
Author(s):  
Hassem Geha ◽  
Ibrahim Nasseh ◽  
Marcel Noujeim
Keyword(s):  
Mathematical Model ◽  
Digital Image ◽  
Histogram Equalization ◽  
Polynomial Model ◽  
The Other ◽  
Degree Polynomial ◽  
Significant Difference ◽  
Digital Image Enhancement ◽  
Factor Interaction ◽  
Three Factor

Objective : The purpose of this study is to compare the detected number of holes on a stepwedge on images resulting from the application of the 5th degree polynomial model compared to the images resulting from the application of linear enhancement. Material and Methods : A 10-step aluminum step wedge with holes randomly drilled on each step was exposed with three different kVp and five exposure times per kVp on a Schick33® sensor. The images were enhanced by brightness/contrast adjustment, histogram equalization and with the 5th degree polynomial model and compared to the original non-enhanced images by six observers in two separate readings. Results : There was no significant difference between the readers and between the first and second reading. There was a significant three-factor interaction among Method, Exposure time, and kVp in detecting holes. The overall pattern was: “Poly” results in the highest counts, “Original” in the lowest counts, with “B/C” and “Equalized” intermediate. Conclusion : The 5th degree polynomial model showed more holes when compared to the other modalities.

scholarly journals Catalytic Benzylation of o-Cresol with Benzyl Alcohol: A Mathematical Model

2012 ◽  
Vol 47 (1) ◽  
pp. 137-142
Author(s):  
AA Rana ◽  
M Kamruzzaman ◽  
M Saha
Keyword(s):  
Mathematical Model ◽  
Experimental Design ◽  
Benzyl Alcohol ◽  
Reaction Temperature ◽  
Molar Ratio ◽  
Single Factor ◽  
Suggested Model

Benzylation of o-cresol with benzyl alcohol (Bz-OH) in presence of 94% H2SO4 as catalyst was studied statistically with a two-levels threefactored   experimental design to study the effects of single factor and effects of their interactions on the yield of benzylated product. Reaction   temperature, molar ratio of o-cresol to Bz-OH and amount of 94% H2SO4 were considered as the major variables. A mathematical model   was derived to calculate the predicted yield of benzyl o-cresol as y = 0.419T+12.4055m+16.17w-0.0525Tm-2.606mw-   0.094Tw+0.0175Tmw-6.25; where, T = temperature (oC), m = o-cresol to Bz-OH molar ratio, w = amount of catalyst (% by wt. of o-cresol)   and y = yield. The adequacy of the suggested model was checked up and the discrepancies between the experimental and calculated values   did not exceed ± 0.79%. DOI: http://dx.doi.org/10.3329/bjsir.v47i1.10727 Bangladesh J. Sci. Ind. Res. 47(1), 137-142, 2012

scholarly journals tert.-Butylation of Toluene: A Statistical Study

1970 ◽  
Vol 43 (4) ◽  
pp. 545-552
Author(s):  
Mohammad Ismail ◽  
Mohammad Abu Hanif ◽  
Mirza Galib ◽  
Manoranjan Saha
Keyword(s):  
Statistical Model ◽  
Aluminum Chloride ◽  
Molar Ratio ◽  
Butyl Chloride ◽  
Anhydrous Aluminum Chloride ◽  
Tert Butyl ◽  
Catalyst Temperature ◽  
Experimental Yield ◽  
The Difference ◽  
Tert Butyl Chloride

A statistical model was developed for the alkylation of toluene with tert.-butyl chloride in presence of anhydrous aluminum chloride as catalyst. Temperature, molar ratio of toluene to tert.-butyl chloride and amount of anhydrous aluminum chloride were chosen for investigation. A set of trials was planned according to a 3 factor 2-level Yates pattern experimental design with 2 replicates and the center point trial with 4 replicates. The critical response was the yield of tert.-butyl toluene. Two- and three-factor interaction effects together with the main effects were statistically significant. The adequacy of the suggested model was checked up. The difference between the experimental and predicted yields did not exceed 2.22%. The best yield of the tert.-butyl toluene was 51.2%. Key words: tert. Butylation, Yates pattern, Experimental yield, Statistical model.     doi: 10.3329/bjsir.v43i4.2245 Bangladesh J. Sci. Ind. Res. 43(4), 545-552, 2008

scholarly journals Application of a Mathematical Model by Means of Experimental Design to Alkylation of o-Cresol with Cyclohexene

2012 ◽  
Vol 60 (1) ◽  
pp. 79-85
Author(s):  
Mohammad Kamruzzaman ◽  
Ashequl Alam Rana ◽  
Md Zahangir Alam ◽  
Manoranjan Saha
Keyword(s):  
Mathematical Model ◽  
Experimental Design ◽  
Factorial Design ◽  
Reaction Temperature ◽  
Perchloric Acid ◽  
Molar Ratio ◽  
High Yield ◽  
Alkylation Reaction ◽  
Suggested Model ◽  
Reaction Conditions

Alkylation of o-cresol with cyclohexene in the presence of perchloric acid as catalyst was studied statistically with a three-factored experimental design. Factorial design was employed to study the effects of single factors and the effects of their interactions on the yield of alkylation. Reaction temperature, molar ratio of o-cresol to cyclohexene and amount of perchloric acid were considered as the major variables. A mathematical model was derived to calculate the predicted yield of alkylation of o-cresol with cyclohexene in the presence of perchloric acid under certain reaction conditions and cyclohexyl o-cresol was obtained in high yield. The adequacy of the suggested model was checked up and the discrepancies between the experimental and calculated values did not exceed 1.52%. An optimum yield (89.5%) of the product was obtained under the reaction conditions of a temperature of 140º C; a 6:1 molar ratio of ocresol to cyclohexene and a 5% by weight perchloric acid of o-cresol.DOI: http://dx.doi.org/10.3329/dujs.v60i1.10342  Dhaka Univ. J. Sci. 60(1): 79-85 2012 (January)

Sex Differences in Cooperative and Competitive Attitudes in a Northeastern School

1982 ◽  
Vol 50 (3) ◽  
pp. 768-770 ◽  
Author(s):  
Barbara K. Herndon ◽  
Mary D. Carpenter
Keyword(s):  
Sex Differences ◽  
Public School ◽  
School Children ◽  
Upper Class ◽  
Region Of Residence ◽  
The Difference ◽  
Main Effects

Competitiveness and cooperativeness of children in the Northeast were compared to those same attitudes in the Midwest. 102 middle- to upper-class suburban public school children in Grades 2 through 6 were given the Minnesota School Affect Assessment. Contrary to former findings, competitiveness in all grades increased with age. There were main effects for sex for both attitudes. It is proposed that region of residence contributed to the difference found.

Impact of multilayered compression bandages on sub-bandage interface pressure: a model

2011 ◽  
Vol 26 (2) ◽  
pp. 75-83 ◽  
Author(s):  
J Al Khaburi ◽  
E A Nelson ◽  
J Hutchinson ◽  
A A Dehghani-Sanij
Keyword(s):  
Mathematical Model ◽  
Thick Wall ◽  
Compression Bandage ◽  
Leg Ulcers ◽  
Interface Pressure ◽  
Venous Leg Ulcers ◽  
Compression Bandages ◽  
Thick Cylinder ◽  
The Difference ◽  
Interface Pressures

Background Multi-component medical compression bandages are widely used to treat venous leg ulcers. The sub-bandage interface pressures induced by individual components of the multi-component compression bandage systems are not always simply additive. Current models to explain compression bandage performance do not take account of the increase in leg circumference when each bandage is applied, and this may account for the difference between predicted and actual pressures. Objective To calculate the interface pressure when a multi-component compression bandage system is applied to a leg. Method Use thick wall cylinder theory to estimate the sub-bandage pressure over the leg when a multi-component compression bandage is applied to a leg. Results A mathematical model was developed based on thick cylinder theory to include bandage thickness in the calculation of the interface pressure in multi-component compression systems. In multi-component compression systems, the interface pressure corresponds to the sum of the pressures applied by individual bandage layers. However, the change in the limb diameter caused by additional bandage layers should be considered in the calculation. Adding the interface pressure produced by single components without considering the bandage thickness will result in an overestimate of the overall interface pressure produced by the multi-component compression systems. At the ankle (circumference 25 cm) this error can be 19.2% or even more in the case of four components bandaging systems. Conclusion Bandage thickness should be considered when calculating the pressure applied using multi-component compression systems.

Sign in / Sign up

Export Citation Format

Share Document