Chemical engineering research & design, Nov 1, 2021
Abstract The application of pervaporation (PV) as a membrane-based separation process for the rec... more Abstract The application of pervaporation (PV) as a membrane-based separation process for the recovery of dilute organic solutes has become a promising alternative to conventional distillation due to its easy scaleup, energy-saving, process continuity. The present study aims at the modelling of mass transfer during the pervaporation process for ethanol recovery from ethanol/water mixture using a solution-diffusion model at different concentrations (5–20%), and different temperatures (30–60 °C). The results revealed that the estimated values of ethanol reference permeance and water reference permeance were respectively Q0eth = 11.77 ± 0.10 g/m2 h kPa and Q0water = 13.31 ± 0.16 g/m2 h kPa. It was also found that the estimated value of ethanol activation energy (Ea(eth)) was 60.40 ± 6.40 kJ/mol whereas the estimated value of water activation energy (Ea(w)) was 56.09 ± 5.05 kJ/mol. The validation of the suggested solution-diffusion model was assessed in terms of mean absolute percentage error (MAPE) using fermentation broth where it showed high accuracy with a low value of MAPE for the ethanol flux (MAPE = 2.8%), water flux (MAPE = 2%), total flux (MAPE = 3.2%). These findings suggest the solution-diffusion model as an efficient tool for optimizing and controlling the pervaporation process when it is coupled with continuous alcoholic fermentation for bioethanol production.
IOP Conference Series: Materials Science and Engineering, 2020
Curcumin nanoparticles )Cur/GANPs( were formulated based on gum arabic )GA( as a stabilizer coati... more Curcumin nanoparticles )Cur/GANPs( were formulated based on gum arabic )GA( as a stabilizer coatings for nanoparticles through efficient synthesis approach . The current study investigated the antioxidant properties and antihypertensive activity of curcumin )Cur( using various established in vitro assays, such as 1,1-diphenyl-2-picrylhydrazyl )DPPH( as well as angiotensin converting enzyme (ACE( inhibitory activity. The in vitro cytotoxicity of Cur/GANPs against human liver cancer )HepG2 (, and colon cancer )HT29 ( was investigated. The exposure of human cancer cells to Cur/GANPs )1.56-100 μg/ml ( using MTT )3-)4,5dimethylthiazol-2-yl (2,5-diphenyl tetrazolium bromide( has revealed that the Cur/GANPs inhibited the growth of cell lines examined in a dose dependent manner. Hence, Cur/GANPs nanoparticles may have great potential to be applied for cancer treatment.
In this study, an artificial neural network (ANN) is used to develop predictive models for estima... more In this study, an artificial neural network (ANN) is used to develop predictive models for estimating molecular diffusion coefficients of various gases at multiple pressures over a large field of temperatures. Two feed-forward neural networks NN1 and NN2 are trained using six physicochemical properties: molecular weight, critical volume, critical temperature, dipole moment, temperature, and pressure for NN1 and molecular weight, critical pressure, critical temperature, dipole moment, temperature, and pressure for NN2. The diffusion coefficients are regarded as the output. A set of 1252 gases (941 non-polar gases and 311 polar gases) is used for training and testing the ANN performance, and good correlations are found ( R = 0.986 for NN1 and R = 0.988 for NN2). The result of the sensitivity analysis shows the importance of the six input parameters selected for modeling the diffusion coefficient. Moreover, the present ANN model provides more accurate predictions than other models.
In the current study, an artificial neural network (ANN) and multiple linear regressions (MLR) ha... more In the current study, an artificial neural network (ANN) and multiple linear regressions (MLR) have been used to develop predictive models for the estimation of molecular diffusion coefficients of 1252 polar and non-polar binary gases at multiple pressures over a wide range of temperatures and substances. The quality and reliability of each method were estimated in terms of the correlation coefficient (R), mean squared errors (MSE), root mean squared error (RMSE), and in terms of external validation coefficients (Q2ext). The comparison between the artificial neural network (ANN) and the multiple linear regressions (MLR) revealed that the neural network models showed a good predicting ability with lower errors (the roots of the mean squared errors in the total database were 0.1400 for ANN1 and 0.1300 for ANN2), and (root mean squared errors in the total databases were 0.5172 for MLR1 and 0.5000 for MLR2).
This study aims at reviewing the alternative techniques for bioethanol recovery, highlighting its... more This study aims at reviewing the alternative techniques for bioethanol recovery, highlighting its advantages and disadvantages, and to investigate the technical challenges facing these alternatives to be widely used. The findings showed that the integration of these techniques with the fermentation process did not meet a large acceptance in the industrial sector. The majority of conducted studies were mainly focusing on ethanol recovery from aqueous standard solution rather than the investigation of these techniques performance in fermentation-separation coupled system. In this context, pervaporation has received more attention as a promising alternative to distillation. However, some challenges are facing the integration of these techniques in the industrial scale as the fouling problem in pervaporation, the toxicity of solvent in liquid extraction, energy consumption in vacuum fermentation. It was also found that there is a lack of the technical economic analysis for these techniq...
Gynura procumbens is one of the most common medicinal plants with extensive pharmacological prope... more Gynura procumbens is one of the most common medicinal plants with extensive pharmacological properties. Light intensity and nitrogenous fertilisers are two main limiting factors in primary and secondary metabolism in plants. Information on the effects of shade levels and nitrogenous fertiliser rates on phytochemical content and antioxidant activity of G. procumbens is much scarce. This justifies an in-depth study to determine the effects of phytochemical content and antioxidant activity. This study was conducted with four levels of shade (0, 30, 50, and 70%) and four nitrogen fertilizer rates (0, 100, 200 and 300 kg N ha-1). Data measurements were performed on protein content, C:N ratio, total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (DPPH, FRAP) and flavonoid acids. The results showed that decreases in total phenol, flavonoid contents, C:N ratio and antioxidant activity were recorded with increasing shade levels and nitrogen rates. Protein content...
International journal of applied engineering research, 2017
The aim of the presented study was to evaluate the potential of molasses as bioethanol feedstock ... more The aim of the presented study was to evaluate the potential of molasses as bioethanol feedstock by studying the effect of different operating conditions on fermentation yield including initial sugar concentration (25-150 g/L), pH (4.5-9.5), and temperature (30-50°C). Molasses composition analyses indicated its richness with sucrose and fermentable sugars which qualify it as a promising feedstock for bioethanol production. The highest ethanol production (49 g/L) was achieved with an initial sugar = 150 g/L, pH = 4.5 but the maximum ethanol yield has been noted for: initial sugar concentration = 50 g/L, pH=4.5 and 30 °C of temperature which represent the optimum conditions for the fermentation. The kinetics study of fermentation experiment carried out under optimal conditions revealed that the fermentation reaction occurs in 3 phases: lag phase, acceleration phase and final phase.
The present work aims to study the pharmacokinetics parameters of vancomycin in Saudi patients, a... more The present work aims to study the pharmacokinetics parameters of vancomycin in Saudi patients, also to develop new equations for the prediction of these parameters from the population data based on their lab data. Data were coded individually, and analyzed as a single cohort or with stratification by the gender, age, and age group. The statistical software SPSS 22 was used for all analyses. 131 patients met the inclusion criteria and their data were analyzed in this study. The patients' sample comprised 83 males (63.4%) and 48 females (36.6%). The mean age was 44.0±27.5 years (mean±SD) with an age range of 0.5-86 years. The mean weight of patients was 60.8±31.2 kg (range, 3-176 kg) and mean height 140.3±42.0 cm (range, 30-185 cm). The dosing rate of vancomycin in these patients was 11.74±89.24 mg/hr (range, 1.83-562.5
In the last few decades, finding alternatives to fossil fuels has become a hot issue across all i... more In the last few decades, finding alternatives to fossil fuels has become a hot issue across all international frontiers. The Intergovernmental Panel on Climate Change (IPCC) has shed light on the feasibility of using biofuels to meet the growing energy demand as well as to reduce CO2 emissions which are a major cause of global warming, especially in the transportation sector. The production and use of biofuels in developing countries have further advantages, including social and economic benefits. On the other hand, the biofuel industry in some developing countries is facing critical challenges related to food security, land availability, production cost, etc. In this regard, several studies have recently been conducted to address these issues, and this paper comprehensively reviews these cases with respect to the successes, failures, and challenges faced by developing countries, such as Brazil, Africa and India, in expanding their biofuel production. It is clear that all the effort...
Chemical engineering research & design, Nov 1, 2021
Abstract The application of pervaporation (PV) as a membrane-based separation process for the rec... more Abstract The application of pervaporation (PV) as a membrane-based separation process for the recovery of dilute organic solutes has become a promising alternative to conventional distillation due to its easy scaleup, energy-saving, process continuity. The present study aims at the modelling of mass transfer during the pervaporation process for ethanol recovery from ethanol/water mixture using a solution-diffusion model at different concentrations (5–20%), and different temperatures (30–60 °C). The results revealed that the estimated values of ethanol reference permeance and water reference permeance were respectively Q0eth = 11.77 ± 0.10 g/m2 h kPa and Q0water = 13.31 ± 0.16 g/m2 h kPa. It was also found that the estimated value of ethanol activation energy (Ea(eth)) was 60.40 ± 6.40 kJ/mol whereas the estimated value of water activation energy (Ea(w)) was 56.09 ± 5.05 kJ/mol. The validation of the suggested solution-diffusion model was assessed in terms of mean absolute percentage error (MAPE) using fermentation broth where it showed high accuracy with a low value of MAPE for the ethanol flux (MAPE = 2.8%), water flux (MAPE = 2%), total flux (MAPE = 3.2%). These findings suggest the solution-diffusion model as an efficient tool for optimizing and controlling the pervaporation process when it is coupled with continuous alcoholic fermentation for bioethanol production.
IOP Conference Series: Materials Science and Engineering, 2020
Curcumin nanoparticles )Cur/GANPs( were formulated based on gum arabic )GA( as a stabilizer coati... more Curcumin nanoparticles )Cur/GANPs( were formulated based on gum arabic )GA( as a stabilizer coatings for nanoparticles through efficient synthesis approach . The current study investigated the antioxidant properties and antihypertensive activity of curcumin )Cur( using various established in vitro assays, such as 1,1-diphenyl-2-picrylhydrazyl )DPPH( as well as angiotensin converting enzyme (ACE( inhibitory activity. The in vitro cytotoxicity of Cur/GANPs against human liver cancer )HepG2 (, and colon cancer )HT29 ( was investigated. The exposure of human cancer cells to Cur/GANPs )1.56-100 μg/ml ( using MTT )3-)4,5dimethylthiazol-2-yl (2,5-diphenyl tetrazolium bromide( has revealed that the Cur/GANPs inhibited the growth of cell lines examined in a dose dependent manner. Hence, Cur/GANPs nanoparticles may have great potential to be applied for cancer treatment.
In this study, an artificial neural network (ANN) is used to develop predictive models for estima... more In this study, an artificial neural network (ANN) is used to develop predictive models for estimating molecular diffusion coefficients of various gases at multiple pressures over a large field of temperatures. Two feed-forward neural networks NN1 and NN2 are trained using six physicochemical properties: molecular weight, critical volume, critical temperature, dipole moment, temperature, and pressure for NN1 and molecular weight, critical pressure, critical temperature, dipole moment, temperature, and pressure for NN2. The diffusion coefficients are regarded as the output. A set of 1252 gases (941 non-polar gases and 311 polar gases) is used for training and testing the ANN performance, and good correlations are found ( R = 0.986 for NN1 and R = 0.988 for NN2). The result of the sensitivity analysis shows the importance of the six input parameters selected for modeling the diffusion coefficient. Moreover, the present ANN model provides more accurate predictions than other models.
In the current study, an artificial neural network (ANN) and multiple linear regressions (MLR) ha... more In the current study, an artificial neural network (ANN) and multiple linear regressions (MLR) have been used to develop predictive models for the estimation of molecular diffusion coefficients of 1252 polar and non-polar binary gases at multiple pressures over a wide range of temperatures and substances. The quality and reliability of each method were estimated in terms of the correlation coefficient (R), mean squared errors (MSE), root mean squared error (RMSE), and in terms of external validation coefficients (Q2ext). The comparison between the artificial neural network (ANN) and the multiple linear regressions (MLR) revealed that the neural network models showed a good predicting ability with lower errors (the roots of the mean squared errors in the total database were 0.1400 for ANN1 and 0.1300 for ANN2), and (root mean squared errors in the total databases were 0.5172 for MLR1 and 0.5000 for MLR2).
This study aims at reviewing the alternative techniques for bioethanol recovery, highlighting its... more This study aims at reviewing the alternative techniques for bioethanol recovery, highlighting its advantages and disadvantages, and to investigate the technical challenges facing these alternatives to be widely used. The findings showed that the integration of these techniques with the fermentation process did not meet a large acceptance in the industrial sector. The majority of conducted studies were mainly focusing on ethanol recovery from aqueous standard solution rather than the investigation of these techniques performance in fermentation-separation coupled system. In this context, pervaporation has received more attention as a promising alternative to distillation. However, some challenges are facing the integration of these techniques in the industrial scale as the fouling problem in pervaporation, the toxicity of solvent in liquid extraction, energy consumption in vacuum fermentation. It was also found that there is a lack of the technical economic analysis for these techniq...
Gynura procumbens is one of the most common medicinal plants with extensive pharmacological prope... more Gynura procumbens is one of the most common medicinal plants with extensive pharmacological properties. Light intensity and nitrogenous fertilisers are two main limiting factors in primary and secondary metabolism in plants. Information on the effects of shade levels and nitrogenous fertiliser rates on phytochemical content and antioxidant activity of G. procumbens is much scarce. This justifies an in-depth study to determine the effects of phytochemical content and antioxidant activity. This study was conducted with four levels of shade (0, 30, 50, and 70%) and four nitrogen fertilizer rates (0, 100, 200 and 300 kg N ha-1). Data measurements were performed on protein content, C:N ratio, total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (DPPH, FRAP) and flavonoid acids. The results showed that decreases in total phenol, flavonoid contents, C:N ratio and antioxidant activity were recorded with increasing shade levels and nitrogen rates. Protein content...
International journal of applied engineering research, 2017
The aim of the presented study was to evaluate the potential of molasses as bioethanol feedstock ... more The aim of the presented study was to evaluate the potential of molasses as bioethanol feedstock by studying the effect of different operating conditions on fermentation yield including initial sugar concentration (25-150 g/L), pH (4.5-9.5), and temperature (30-50°C). Molasses composition analyses indicated its richness with sucrose and fermentable sugars which qualify it as a promising feedstock for bioethanol production. The highest ethanol production (49 g/L) was achieved with an initial sugar = 150 g/L, pH = 4.5 but the maximum ethanol yield has been noted for: initial sugar concentration = 50 g/L, pH=4.5 and 30 °C of temperature which represent the optimum conditions for the fermentation. The kinetics study of fermentation experiment carried out under optimal conditions revealed that the fermentation reaction occurs in 3 phases: lag phase, acceleration phase and final phase.
The present work aims to study the pharmacokinetics parameters of vancomycin in Saudi patients, a... more The present work aims to study the pharmacokinetics parameters of vancomycin in Saudi patients, also to develop new equations for the prediction of these parameters from the population data based on their lab data. Data were coded individually, and analyzed as a single cohort or with stratification by the gender, age, and age group. The statistical software SPSS 22 was used for all analyses. 131 patients met the inclusion criteria and their data were analyzed in this study. The patients' sample comprised 83 males (63.4%) and 48 females (36.6%). The mean age was 44.0±27.5 years (mean±SD) with an age range of 0.5-86 years. The mean weight of patients was 60.8±31.2 kg (range, 3-176 kg) and mean height 140.3±42.0 cm (range, 30-185 cm). The dosing rate of vancomycin in these patients was 11.74±89.24 mg/hr (range, 1.83-562.5
In the last few decades, finding alternatives to fossil fuels has become a hot issue across all i... more In the last few decades, finding alternatives to fossil fuels has become a hot issue across all international frontiers. The Intergovernmental Panel on Climate Change (IPCC) has shed light on the feasibility of using biofuels to meet the growing energy demand as well as to reduce CO2 emissions which are a major cause of global warming, especially in the transportation sector. The production and use of biofuels in developing countries have further advantages, including social and economic benefits. On the other hand, the biofuel industry in some developing countries is facing critical challenges related to food security, land availability, production cost, etc. In this regard, several studies have recently been conducted to address these issues, and this paper comprehensively reviews these cases with respect to the successes, failures, and challenges faced by developing countries, such as Brazil, Africa and India, in expanding their biofuel production. It is clear that all the effort...
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