Pub Date : 2024-01-01DOI: 10.1177/14686783241226858
Sahmoune Mohamed Nasser, M. Abbas, Mohamed Trari
Biomaterials are a class of porous materials that have been widely exploited over the past two decades. However, the implications of controlling adsorption by rate-limiting steps are still not adequately established. Identifying the rate-limiting step is a promising approach for the design of adsorption systems. In this review, we study in detail the rate-limiting step of the adsorption of dyes in aqueous media on biomaterials to rationalize the factors governing the rate-limiting step involved in the adsorption process using empirical kinetics and mass transfer models. This knowledge is then applied to identify the best fit of these models to study the rate-controlling step involved in the adsorption process, which is crucial for the design of the adsorption system. This review first studies the limiting step of adsorption of dyes in an aqueous medium on biomaterials. Kinetic modeling is used to better understand the rate control step involved in biosorption. Generally, the equations used are empirical models of kinetics and mass transfer and the biomaterials come from the following categories: agricultural and industrial waste, algae, fungi, bacteria, and plants. In most adsorption studies reported in this review, the pseudo second-order model was found to be best suited for fitting the kinetic data of dyes on biomaterials, indicating that chemisorption is the rate-limiting step that controls adsorption. Concerning the diffusion effects of mass transfer, intraparticle diffusion is among the most often used models to examine the rate-limiting step which is controlled by both film diffusion and intraparticle diffusion. The first takes place when the external transfer is greater than the internal transfer while the opposite occurs in the case of porous diffusion. However, the majority of works do not study the real step of controlling the overall adsorption kinetics, namely, film diffusion or intraparticle diffusion.
{"title":"Understanding the rate-limiting step adsorption kinetics onto biomaterials for mechanism adsorption control","authors":"Sahmoune Mohamed Nasser, M. Abbas, Mohamed Trari","doi":"10.1177/14686783241226858","DOIUrl":"https://doi.org/10.1177/14686783241226858","url":null,"abstract":"Biomaterials are a class of porous materials that have been widely exploited over the past two decades. However, the implications of controlling adsorption by rate-limiting steps are still not adequately established. Identifying the rate-limiting step is a promising approach for the design of adsorption systems. In this review, we study in detail the rate-limiting step of the adsorption of dyes in aqueous media on biomaterials to rationalize the factors governing the rate-limiting step involved in the adsorption process using empirical kinetics and mass transfer models. This knowledge is then applied to identify the best fit of these models to study the rate-controlling step involved in the adsorption process, which is crucial for the design of the adsorption system. This review first studies the limiting step of adsorption of dyes in an aqueous medium on biomaterials. Kinetic modeling is used to better understand the rate control step involved in biosorption. Generally, the equations used are empirical models of kinetics and mass transfer and the biomaterials come from the following categories: agricultural and industrial waste, algae, fungi, bacteria, and plants. In most adsorption studies reported in this review, the pseudo second-order model was found to be best suited for fitting the kinetic data of dyes on biomaterials, indicating that chemisorption is the rate-limiting step that controls adsorption. Concerning the diffusion effects of mass transfer, intraparticle diffusion is among the most often used models to examine the rate-limiting step which is controlled by both film diffusion and intraparticle diffusion. The first takes place when the external transfer is greater than the internal transfer while the opposite occurs in the case of porous diffusion. However, the majority of works do not study the real step of controlling the overall adsorption kinetics, namely, film diffusion or intraparticle diffusion.","PeriodicalId":20859,"journal":{"name":"Progress in Reaction Kinetics and Mechanism","volume":"16 12","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139455314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.1177/14686783231218882
Mohamed A El-Rahman, Mahmoud F. Ibrahim, M. F. Fathalla, S. El-Sadany, Ezzat A. Hamed, A. Z. Omar
The reactions of 5- and 7-substituted isatin derivatives (H, Me, Cl, Br) with piperidine in 80% aqueous methanol gave the corresponding 1-(2’-amino-5’- or 3’- substituted phenyl)-2-(piperidin-1-yl) ethane-1,2-dione derivatives. The reaction is proceeded through nucleophilic attack on C-2 followed by ring opening process. The reaction showed a second order and the isokinetic temperature is 169 K indicating that the reaction is entropy controlled. The constant ∆G# value, the linear plot of ∆H# versus ∆S#, plot of log kN values at high temperature versus those at low temperatures indicated that a unified mechanism of the reactions for all substituents. The σo-Taft's constants are linearly correlated with log kN values and the ρ values are (2.01–1.86) pointing out that inductive effect of substituent is predominant and the rate-limiting is the breakdown of the tetrahedral intermediate T− and the ring opening is catalyzed by water.
{"title":"Entropy controlled reaction of piperidine with isatin derivatives in 80% aqueous methanol","authors":"Mohamed A El-Rahman, Mahmoud F. Ibrahim, M. F. Fathalla, S. El-Sadany, Ezzat A. Hamed, A. Z. Omar","doi":"10.1177/14686783231218882","DOIUrl":"https://doi.org/10.1177/14686783231218882","url":null,"abstract":"The reactions of 5- and 7-substituted isatin derivatives (H, Me, Cl, Br) with piperidine in 80% aqueous methanol gave the corresponding 1-(2’-amino-5’- or 3’- substituted phenyl)-2-(piperidin-1-yl) ethane-1,2-dione derivatives. The reaction is proceeded through nucleophilic attack on C-2 followed by ring opening process. The reaction showed a second order and the isokinetic temperature is 169 K indicating that the reaction is entropy controlled. The constant ∆G# value, the linear plot of ∆H# versus ∆S#, plot of log kN values at high temperature versus those at low temperatures indicated that a unified mechanism of the reactions for all substituents. The σo-Taft's constants are linearly correlated with log kN values and the ρ values are (2.01–1.86) pointing out that inductive effect of substituent is predominant and the rate-limiting is the breakdown of the tetrahedral intermediate T− and the ring opening is catalyzed by water.","PeriodicalId":20859,"journal":{"name":"Progress in Reaction Kinetics and Mechanism","volume":"108 ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139025215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-01DOI: 10.1177/14686783211045815
R. Kalal, D. Panday
The oxidation of furfural (2-furaldehyde), by benzimidazolium dichromate (BIDC) in dimethyl sulfoxide, leads to the formation of 2-furoic acid. The reaction is first order with respect to BIDC and hydrogen-ion. However, Michaelis–Menten type kinetics was observed with respect to furfural. The formation constants of furfural-BIDC complexes and the rates of their decomposition have been evaluated at different temperatures. Thermodynamic parameters of the complex formation and activation parameters for the decomposition of the complexes have been calculated. The deuterium isotope effect observed in the oxidation of furfural (kH/kD = 6.23 at 298 K) indicated an α-C-H bond cleavage in the rate-determining step. The reaction has been studied in 19 organic solvents. The analysis of the solvent effect showed that the role of cation-solvation is major. Based on the kinetic data, analysis of the solvent effect and the result of some non-kinetic parameters, a mechanism involving rate-determining oxidative decomposition of the complex, through hydride-ion transfer via a cyclic transition state, to give the corresponding product is suggested.
{"title":"Kinetics and mechanism of the oxidation of furfural by benzimidazolium dichromate under non aqueous medium","authors":"R. Kalal, D. Panday","doi":"10.1177/14686783211045815","DOIUrl":"https://doi.org/10.1177/14686783211045815","url":null,"abstract":"The oxidation of furfural (2-furaldehyde), by benzimidazolium dichromate (BIDC) in dimethyl sulfoxide, leads to the formation of 2-furoic acid. The reaction is first order with respect to BIDC and hydrogen-ion. However, Michaelis–Menten type kinetics was observed with respect to furfural. The formation constants of furfural-BIDC complexes and the rates of their decomposition have been evaluated at different temperatures. Thermodynamic parameters of the complex formation and activation parameters for the decomposition of the complexes have been calculated. The deuterium isotope effect observed in the oxidation of furfural (kH/kD = 6.23 at 298 K) indicated an α-C-H bond cleavage in the rate-determining step. The reaction has been studied in 19 organic solvents. The analysis of the solvent effect showed that the role of cation-solvation is major. Based on the kinetic data, analysis of the solvent effect and the result of some non-kinetic parameters, a mechanism involving rate-determining oxidative decomposition of the complex, through hydride-ion transfer via a cyclic transition state, to give the corresponding product is suggested.","PeriodicalId":20859,"journal":{"name":"Progress in Reaction Kinetics and Mechanism","volume":"229 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73952750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1177/14686783221090376
Meng Ding, Fan Yang, Q. Lv, Qiongfang Liu
In this current work, two fresh transition metal coordination polymers (CPs) have been created with the reaction between terphenyl-3,3″,5,5″-tetracarboxylic acid (H4L), the symmetrical rigid carboxylic acid ligand and the relevant metal salts under the reaction conditions of solvothermal, and the chemical compositions of the compounds respectively are {[Cu2(TPTC) (DMF)2(H2O)]·2DMF·2H2O} (2) and {[Zn (TPTC) (1,2-bimb)2]·4(H2O)}n (1, bimb = 1,2-bis((1H-imidazol-1-yl)methyl)benzene). Moreover, the prevention and nursing values of the compound on postoperative infection was explored and their corresponding mechanism also was investigated. Firstly, enzyme linked immunosorbent assay kit (ELISA) was employed to detect the release of inflammatory cytokines into plasma. Additionally, the expression of the bacterial survival genes was determined via exploiting the real time reverse transcription-polymerase chain reaction (RT-PCR) after treated with the compound.
{"title":"Two coordination polymers: Crystal structures, prevention and nursing values on postoperative infection","authors":"Meng Ding, Fan Yang, Q. Lv, Qiongfang Liu","doi":"10.1177/14686783221090376","DOIUrl":"https://doi.org/10.1177/14686783221090376","url":null,"abstract":"In this current work, two fresh transition metal coordination polymers (CPs) have been created with the reaction between terphenyl-3,3″,5,5″-tetracarboxylic acid (H4L), the symmetrical rigid carboxylic acid ligand and the relevant metal salts under the reaction conditions of solvothermal, and the chemical compositions of the compounds respectively are {[Cu2(TPTC) (DMF)2(H2O)]·2DMF·2H2O} (2) and {[Zn (TPTC) (1,2-bimb)2]·4(H2O)}n (1, bimb = 1,2-bis((1H-imidazol-1-yl)methyl)benzene). Moreover, the prevention and nursing values of the compound on postoperative infection was explored and their corresponding mechanism also was investigated. Firstly, enzyme linked immunosorbent assay kit (ELISA) was employed to detect the release of inflammatory cytokines into plasma. Additionally, the expression of the bacterial survival genes was determined via exploiting the real time reverse transcription-polymerase chain reaction (RT-PCR) after treated with the compound.","PeriodicalId":20859,"journal":{"name":"Progress in Reaction Kinetics and Mechanism","volume":"77 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83307390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1177/14686783221090374
F. Alzahrani, Muhammad Ijaz Khan
Here, we scrutinize the entropy analysis in magnetohydrodynamic flow of second-grade nanomaterials with melting effect subject to stretchable bended surface. Heat attribution is modeled through first law of thermodynamics with radiation effect. Major physical effect of random and thermophoretic motion is also addressed. Feature of irreversibility (entropy rate) analysis is also discussed. Isothermal cubic autocatalyses chemical reaction at catalytic surface is discussed. Nonlinear dimensionless differential system is developed through adequate transformation. Optimal homeotypic analysis method (OHAM) is employed to construct convergent solution. Influence of physical variables on entropy rate, fluid flow, concentration, and thermal field is discussed. An augmentation in fluid flow is noticed through curvature variable, while reverse effect holds for magnetic variable. A reverse effect holds for fluid flow and thermal field through melting variable. Entropy analysis is augmented with variation in melting variable. Reduction occurs in concentration through thermophoretic variable, while an opposite effect holds for thermal field. An increment in melting variable leads to reduced concentration. Larger estimation of radiation variable improves entropy analysis.
{"title":"Melting aspects in flow of second grade nanomaterial with homogeneous–heterogeneous reactions and irreversibility phenomenon: A residual error analysis","authors":"F. Alzahrani, Muhammad Ijaz Khan","doi":"10.1177/14686783221090374","DOIUrl":"https://doi.org/10.1177/14686783221090374","url":null,"abstract":"Here, we scrutinize the entropy analysis in magnetohydrodynamic flow of second-grade nanomaterials with melting effect subject to stretchable bended surface. Heat attribution is modeled through first law of thermodynamics with radiation effect. Major physical effect of random and thermophoretic motion is also addressed. Feature of irreversibility (entropy rate) analysis is also discussed. Isothermal cubic autocatalyses chemical reaction at catalytic surface is discussed. Nonlinear dimensionless differential system is developed through adequate transformation. Optimal homeotypic analysis method (OHAM) is employed to construct convergent solution. Influence of physical variables on entropy rate, fluid flow, concentration, and thermal field is discussed. An augmentation in fluid flow is noticed through curvature variable, while reverse effect holds for magnetic variable. A reverse effect holds for fluid flow and thermal field through melting variable. Entropy analysis is augmented with variation in melting variable. Reduction occurs in concentration through thermophoretic variable, while an opposite effect holds for thermal field. An increment in melting variable leads to reduced concentration. Larger estimation of radiation variable improves entropy analysis.","PeriodicalId":20859,"journal":{"name":"Progress in Reaction Kinetics and Mechanism","volume":"36 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75896975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1177/14686783221090373
Yan Yang, Shenmin Zhang, Yi-Qian Zhang, Liang Chen, Tao Xiong
In the present study, via using the mixed-ligand synthesis approach, a new Mn(II)-containing coordination polymer (CP) with the chemical formula of {[Mn3(timb)2(SO3–IPA)2(H2O)2]·8H2O} n (1) has been successfully prepared via reaction of MnCl2·4H2O with the tripodal linker 1,3,5-tris(2-methylimidazole-1-yl)benzene (timb) and aromatic dicarboxylic acid ligand –SO3 group functionalized isophthalic acid (H2IPA) ligand. Furthermore, the biological activity of the new compound on renal calculus was assessed, and the related mechanism was explored as well. The Calcium Colorimetric Assay was conducted and the concentration of Ca2+ in urine was determined. The western blotting assay was conducted and the expression levels of the osteopontin (OPN) in the distal tubule were measured. Molecular docking simulation revealed that the carboxyl, iminazole, and sulfonate groups were all involving into the binding interactions with the target protein, and therefore exhibited strong biological activity.
{"title":"A new mixed-ligand Mn(II) coordination polymer: Protective and nursing values on renal calculus via reducing the Ca2+ concentration in urine","authors":"Yan Yang, Shenmin Zhang, Yi-Qian Zhang, Liang Chen, Tao Xiong","doi":"10.1177/14686783221090373","DOIUrl":"https://doi.org/10.1177/14686783221090373","url":null,"abstract":"In the present study, via using the mixed-ligand synthesis approach, a new Mn(II)-containing coordination polymer (CP) with the chemical formula of {[Mn3(timb)2(SO3–IPA)2(H2O)2]·8H2O} n (1) has been successfully prepared via reaction of MnCl2·4H2O with the tripodal linker 1,3,5-tris(2-methylimidazole-1-yl)benzene (timb) and aromatic dicarboxylic acid ligand –SO3 group functionalized isophthalic acid (H2IPA) ligand. Furthermore, the biological activity of the new compound on renal calculus was assessed, and the related mechanism was explored as well. The Calcium Colorimetric Assay was conducted and the concentration of Ca2+ in urine was determined. The western blotting assay was conducted and the expression levels of the osteopontin (OPN) in the distal tubule were measured. Molecular docking simulation revealed that the carboxyl, iminazole, and sulfonate groups were all involving into the binding interactions with the target protein, and therefore exhibited strong biological activity.","PeriodicalId":20859,"journal":{"name":"Progress in Reaction Kinetics and Mechanism","volume":"73 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86143552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1177/14686783221090377
A. Mahmoud
Developing countries suffering from the toxicity of different industrial effluents especially dyes. This study successfully prepared and characterized nano-bentonite for anionic dye removal (DY 50). The prepared nanoparticles were characterized by X-Ray Diffraction (XRD), X-ray Fluorescence (XRF), Scanning Electron Microscope (SEM), EDAX analysis, FT-IR, and TGA and the obtained results indicated the formation of nanoparticles with an average size of 15 nm. The effect of different operating conditions was studied using different pH, dose, contact time, temperature, and initial DY 50 concentrations. The obtained results indicated that nano bentonite was able to adsorb about 78.3 and 100% for initial concentrations of 100±8.1 and 20 ±1.62 mg/L, respectively. The optimum removal conditions were observed at acidic media (pH 3) using sorbent material dosage 1 g/L for 45 min and 30°C. The adsorption isotherm, kinetic analysis, and thermodynamic behavior were studied by using linear equation form, and the adjusted R2 was compared to detect the preferred models. The adsorption isotherm indicated that heterogeneous, as well as multilayer adsorption, plays an important role in the removal of dye. Kinetic studies indicated the chemisorption interaction between sorbed and adsorbed molecules. Thermodynamic behavior indicated the reaction is exothermic with ∆H equal to −5.24 KJ/mol and ∆S equal −74.2 J/K.mol. Finally, this study strongly recommended using nano bentonite for DY 50 removal from an aqueous solution. The RSM relations show significant relations in all removal models with p-value <0.001. The ANN results indicated that the most effective operating conditions are the effect of nano bentonite dose followed by the pH effect.
{"title":"Effect of nano bentonite on direct yellow 50 dye removal; Adsorption isotherm, kinetic analysis, and thermodynamic behavior","authors":"A. Mahmoud","doi":"10.1177/14686783221090377","DOIUrl":"https://doi.org/10.1177/14686783221090377","url":null,"abstract":"Developing countries suffering from the toxicity of different industrial effluents especially dyes. This study successfully prepared and characterized nano-bentonite for anionic dye removal (DY 50). The prepared nanoparticles were characterized by X-Ray Diffraction (XRD), X-ray Fluorescence (XRF), Scanning Electron Microscope (SEM), EDAX analysis, FT-IR, and TGA and the obtained results indicated the formation of nanoparticles with an average size of 15 nm. The effect of different operating conditions was studied using different pH, dose, contact time, temperature, and initial DY 50 concentrations. The obtained results indicated that nano bentonite was able to adsorb about 78.3 and 100% for initial concentrations of 100±8.1 and 20 ±1.62 mg/L, respectively. The optimum removal conditions were observed at acidic media (pH 3) using sorbent material dosage 1 g/L for 45 min and 30°C. The adsorption isotherm, kinetic analysis, and thermodynamic behavior were studied by using linear equation form, and the adjusted R2 was compared to detect the preferred models. The adsorption isotherm indicated that heterogeneous, as well as multilayer adsorption, plays an important role in the removal of dye. Kinetic studies indicated the chemisorption interaction between sorbed and adsorbed molecules. Thermodynamic behavior indicated the reaction is exothermic with ∆H equal to −5.24 KJ/mol and ∆S equal −74.2 J/K.mol. Finally, this study strongly recommended using nano bentonite for DY 50 removal from an aqueous solution. The RSM relations show significant relations in all removal models with p-value <0.001. The ANN results indicated that the most effective operating conditions are the effect of nano bentonite dose followed by the pH effect.","PeriodicalId":20859,"journal":{"name":"Progress in Reaction Kinetics and Mechanism","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89901066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.1177/14686783211072712
M. Anwar, H. Firdous, A. Zubaidi, N. Abbas, S Nadeem
In the current article, induced magnetic field applied on second-grade fluid flow under variable thermal conductivity by an exponentially stretching sheet is taken into account for current analysis. The chemical reaction and viscous dissipation effects under the influence of thermophoresis and Brownian motion are considered on an exponentially stretching sheet. With the above assumptions, a mathematical model was developed in terms of partial differential equations by using the boundary-layer approximations. Similarity transformations in terms of ordinary differential equations considerably simplified this system. The dimensionless system was solved by a numerical procedure, the bvp4c method. The effects of involving physical parameters are presented through graphs and tables. The obtained numerical outcomes of the skin friction coefficient, the Sherwood number, and the Nusselt number are also highlighted in the tabulated form. It is concluded that the velocity and concentration profiles increased due to higher values of material parameter.
{"title":"Computational analysis of induced magnetohydrodynamic non-Newtonian nanofluid flow over nonlinear stretching sheet","authors":"M. Anwar, H. Firdous, A. Zubaidi, N. Abbas, S Nadeem","doi":"10.1177/14686783211072712","DOIUrl":"https://doi.org/10.1177/14686783211072712","url":null,"abstract":"In the current article, induced magnetic field applied on second-grade fluid flow under variable thermal conductivity by an exponentially stretching sheet is taken into account for current analysis. The chemical reaction and viscous dissipation effects under the influence of thermophoresis and Brownian motion are considered on an exponentially stretching sheet. With the above assumptions, a mathematical model was developed in terms of partial differential equations by using the boundary-layer approximations. Similarity transformations in terms of ordinary differential equations considerably simplified this system. The dimensionless system was solved by a numerical procedure, the bvp4c method. The effects of involving physical parameters are presented through graphs and tables. The obtained numerical outcomes of the skin friction coefficient, the Sherwood number, and the Nusselt number are also highlighted in the tabulated form. It is concluded that the velocity and concentration profiles increased due to higher values of material parameter.","PeriodicalId":20859,"journal":{"name":"Progress in Reaction Kinetics and Mechanism","volume":"25 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89836682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1177/1468678320956864
M. Zakari̇anezhad, S. Habibi‐Khorassani, Batoul Maki̇abadi̇, E. Zeydabadi
The reaction kinetics among isoquinoline, dimethyl acetylenedicarboxylate, and indole (as NH-acid) were investigated using ultraviolet (UV) spectrophotometry. The reaction rate equation was obtained, the dependence of the reaction rate on different reactants was determined, and the overall rate constant (kov) was calculated. By studying the effects of solvent, temperature, and concentration on the reaction rate, some useful information was obtained. A logical mechanism consistent with the experimental observations was proposed. Also, comprehensive theoretical studies were performed to evaluate the potential energy surfaces of all structures that participated in the reaction mechanism. Finally, the proposed mechanism was confirmed by the obtained results and the probable and logical reaction paths and also a correct product configuration were suggested based on the theoretical results.
{"title":"Three-component reaction involving isoquinoline and dimethyl acethylenedicarboxylate in the presence of indole: Theoretical and experimental investigations of the reaction mechanism","authors":"M. Zakari̇anezhad, S. Habibi‐Khorassani, Batoul Maki̇abadi̇, E. Zeydabadi","doi":"10.1177/1468678320956864","DOIUrl":"https://doi.org/10.1177/1468678320956864","url":null,"abstract":"The reaction kinetics among isoquinoline, dimethyl acetylenedicarboxylate, and indole (as NH-acid) were investigated using ultraviolet (UV) spectrophotometry. The reaction rate equation was obtained, the dependence of the reaction rate on different reactants was determined, and the overall rate constant (kov) was calculated. By studying the effects of solvent, temperature, and concentration on the reaction rate, some useful information was obtained. A logical mechanism consistent with the experimental observations was proposed. Also, comprehensive theoretical studies were performed to evaluate the potential energy surfaces of all structures that participated in the reaction mechanism. Finally, the proposed mechanism was confirmed by the obtained results and the probable and logical reaction paths and also a correct product configuration were suggested based on the theoretical results.","PeriodicalId":20859,"journal":{"name":"Progress in Reaction Kinetics and Mechanism","volume":"73 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85496429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1177/14686783211010970
Zhangmao Hu, Tong Zhou, Hong Tian, Leihua Feng, Can Yao, Yanshan Yin, Donglin Chen
This work presents a comprehensive study on the effects of pyrolysis parameters (pyrolysis temperature, residence time, and heating rate) on the distribution of pyrolysis products of Miscanthus. Py-GC/MS (Pyrolysis-gas chromatography/mass) was conducted to identify building blocks of value-added chemical from Miscanthus. The results showed that the main pyrolysis products of Miscanthus were ketone, aldehyde, phenol, heterocycles, and aromatic compounds. The representative compounds of ketone and aldehyde compounds produced at different pyrolysis temperatures changed obviously, while the representative compounds of phenolic, heterocyclic, and aromatic compounds had no obvious change. Large-scale pyrolysis of Miscanthus had begun at 400°C, and the relative content of pyrolysis products from Miscanthus reached the maximum of 98.34% at 700°C. The relative peak area ratio of phenol and aromatic compounds reached the maximum and minimum at the residence time of 5 and 10 s, while the relative peak area ratio of ketone compounds showed the opposite trend. The relative peak area ratio of aldehyde compounds was higher under shorter or longer residence time. For heterocyclic compounds, the relative peak area ratio reached the maximum of 27.0% at residence time of 10 s. The faster or slower heating rate was beneficial to the production of aldehyde and phenol compounds. The relative peak area ratio of ketone compounds reached the maximum at 10,000°C/s, 70°C/s, and 10°C/s, and the relative peak area ratio tendency of heterocyclic compounds was similar to ketone. For aromatic compounds, the overall fluctuations were large, and the relative peak area ratio was the highest at the heating rate of 100°C/s.
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