Pub Date : 2022-12-01DOI: 10.1016/j.jciso.2022.100063
Farzaneh Nazari , Rouhi Farajzadeh , Vahid J. Niasar
Hypothesis
The large-scale implementation of hydrogen economy requires immense storage spaces to facilitate the periodic storage/production cycles. Extensive modelling of hydrogen transport in porous media is required to comprehend the hydrogen-induced complexities prior to storage to avoid energy loss. Wettability of hydrogen-brine-rock systems influence flow properties (e.g. capillary pressure and relative permeability curves) and the residual saturations, which are all essential for subsurface hydrogen systems.
Model
This study aims to understand which parameters critically control the contact angle for hydrogen-brine-rock systems using the surface force analysis following the DLVO theory and sensitivity analysis. Furthermore, the effect of roughness is studied using the Cassie-Baxter model.
Findings
Our results reveal no considerable difference between H2 and other gases such as N2. Besides, the inclusion of roughness highly affects the observed apparent contact angles, and even lead to water-repelling features. It was observed that contact angle does not vary significantly with variations of surface charge and density at high salinity, which is representative for reservoir conditions. Based on the analysis, it is speculated that the influence of roughness on contact angle becomes significant at low water saturation (i.e. high capillary pressure).
{"title":"Critical parameters controlling wettability in hydrogen underground storage - An analytical study","authors":"Farzaneh Nazari , Rouhi Farajzadeh , Vahid J. Niasar","doi":"10.1016/j.jciso.2022.100063","DOIUrl":"10.1016/j.jciso.2022.100063","url":null,"abstract":"<div><h3>Hypothesis</h3><p>The large-scale implementation of hydrogen economy requires immense storage spaces to facilitate the periodic storage/production cycles. Extensive modelling of hydrogen transport in porous media is required to comprehend the hydrogen-induced complexities prior to storage to avoid energy loss. Wettability of hydrogen-brine-rock systems influence flow properties (e.g. capillary pressure and relative permeability curves) and the residual saturations, which are all essential for subsurface hydrogen systems.</p></div><div><h3>Model</h3><p>This study aims to understand which parameters critically control the contact angle for hydrogen-brine-rock systems using the surface force analysis following the DLVO theory and sensitivity analysis. Furthermore, the effect of roughness is studied using the Cassie-Baxter model.</p></div><div><h3>Findings</h3><p>Our results reveal no considerable difference between H<sub>2</sub> and other gases such as N<sub>2</sub>. Besides, the inclusion of roughness highly affects the observed apparent contact angles, and even lead to water-repelling features. It was observed that contact angle does not vary significantly with variations of surface charge and density at high salinity, which is representative for reservoir conditions. Based on the analysis, it is speculated that the influence of roughness on contact angle becomes significant at low water saturation (i.e. high capillary pressure).</p></div>","PeriodicalId":73541,"journal":{"name":"JCIS open","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666934X22000216/pdfft?md5=92c5b695290b9f4cec2bff6de00a5075&pid=1-s2.0-S2666934X22000216-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41959748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-01DOI: 10.1016/j.jciso.2022.100067
Mohd Bilal Khan, C. Sasmal
Biosurfactants are widely used in many industrial settings ranging from cosmetic to petroleum industries. Among various biosurfactants available in the market, rhamnolipid is a well-known bacterial biosurfactant produced by the Pseudomonas aeruginosa bacteria. However, despite its wide applications, no detailed and systematic study is available on the rheological characterization of this biosurfactant solution, which is an essential property to investigate for many practical applications. Therefore, this study aims to present a thorough and complete investigation of this biosurfactant's shear and extensional rheological behaviours. While steady shear and small amplitude oscillatory shear (SAOS) measurements were conducted to investigate the shear rheological behaviour, the dripping-onto-substrate (DoS) extensional rheometry technique was used to understand its extensional rheological behaviour. A chemically derived surfactant (cetyltrimethyl ammonium bromide (CTAB)) was also used in our analysis to show and discuss the qualitative and quantitative differences in their rheological behaviours. Along with the detailed rheological study, some studies on the physicochemical properties, such as surface tension, contact angle, particle size analysis, thermal stability, etc., were also conducted to make an overall comparison between the two surfactants. Both surfactants show strong shear-thinning and extensional hardening behaviors in shear and extensional rheological flows, respectively. However, the zero-shear rate viscosity and extensional viscosity are found to be larger for rhamnolipid surfactant solutions than for CTAB. The corresponding shear and extensional relaxation times also follow the same trend. Furthermore, the surface tension is found to be less, and the contact angle is found to be more for rhamnolipid biosurfactant than that for CTAB. Rhamnolipid shows more excellent thermal stability, particularly at high temperatures than CTAB. Therefore, the results and discussion presented in this study will help to choose the present rhamnolipid biosurfactant for any particular application, particularly where the knowledge of the rheological responses of a surfactant solution is essential.
{"title":"A detailed and systematic study on rheological and physicochemical properties of rhamnolipid biosurfactant solutions","authors":"Mohd Bilal Khan, C. Sasmal","doi":"10.1016/j.jciso.2022.100067","DOIUrl":"10.1016/j.jciso.2022.100067","url":null,"abstract":"<div><p>Biosurfactants are widely used in many industrial settings ranging from cosmetic to petroleum industries. Among various biosurfactants available in the market, rhamnolipid is a well-known bacterial biosurfactant produced by the <em>Pseudomonas aeruginosa</em> bacteria. However, despite its wide applications, no detailed and systematic study is available on the rheological characterization of this biosurfactant solution, which is an essential property to investigate for many practical applications. Therefore, this study aims to present a thorough and complete investigation of this biosurfactant's shear and extensional rheological behaviours. While steady shear and small amplitude oscillatory shear (SAOS) measurements were conducted to investigate the shear rheological behaviour, the dripping-onto-substrate (DoS) extensional rheometry technique was used to understand its extensional rheological behaviour. A chemically derived surfactant (cetyltrimethyl ammonium bromide (CTAB)) was also used in our analysis to show and discuss the qualitative and quantitative differences in their rheological behaviours. Along with the detailed rheological study, some studies on the physicochemical properties, such as surface tension, contact angle, particle size analysis, thermal stability, etc., were also conducted to make an overall comparison between the two surfactants. Both surfactants show strong shear-thinning and extensional hardening behaviors in shear and extensional rheological flows, respectively. However, the zero-shear rate viscosity and extensional viscosity are found to be larger for rhamnolipid surfactant solutions than for CTAB. The corresponding shear and extensional relaxation times also follow the same trend. Furthermore, the surface tension is found to be less, and the contact angle is found to be more for rhamnolipid biosurfactant than that for CTAB. Rhamnolipid shows more excellent thermal stability, particularly at high temperatures than CTAB. Therefore, the results and discussion presented in this study will help to choose the present rhamnolipid biosurfactant for any particular application, particularly where the knowledge of the rheological responses of a surfactant solution is essential.</p></div>","PeriodicalId":73541,"journal":{"name":"JCIS open","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666934X22000253/pdfft?md5=ea7f1eef80067bb49fafd728231bca11&pid=1-s2.0-S2666934X22000253-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41245556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-01DOI: 10.1016/j.jciso.2022.100064
Sohita Rajput , Krishnendu Bhattacharyya , Amit Kumar Pandey , Ali J. Chamkha
The physical phenomena of nanofluid at high temperature motivate us to analyze problems with temperature-reliant fluid properties, like viscosity and thermal conductivity. Since in glass blowing, viscosity and thermal conductivity of the fluid may gets affected in such high temperature. This communication deals with the unsteady flow of nanofluid generated by nonlinear expansion of the surface. Temperature-dependent fluid viscosity and thermal conductivity are considered in the investigation of the problem. The flow of nanofluid is modeled using famous the Buongiorno's two-phase model, which includes the simultaneous effect of Brownian motion and thermophoresis diffusion. Appropriate transformations are adopted to obtain the ODEs from governing PDEs. Then MATLAB ‘bvp4c’ computation is used to solve the problem and to get a clear insight of the influences of various parameters. Graphical comparisons are made to check the accuracy of used numerical method. The study explores that heat transfer rate significantly enhances by the index of nonlinearity, variable viscosity and thermal conductivity parameters. Unsteadiness of the flow can be used as a controlling parameter to reduce the surface drag, heat and nano-mass transfer rate. Variable viscosity parameter leads to enhance the velocity near the surface and reducing the concentration of the nanoparticles. The thermal and concentration boundary layer thickens with thermal conductivity parameters. Nanofluid temperature and concentration of nanoparticles decay with nonlinear expanding index.
{"title":"Unsteady axisymmetric flow of nanofluid on nonlinearly expanding surface with variable fluid properties","authors":"Sohita Rajput , Krishnendu Bhattacharyya , Amit Kumar Pandey , Ali J. Chamkha","doi":"10.1016/j.jciso.2022.100064","DOIUrl":"10.1016/j.jciso.2022.100064","url":null,"abstract":"<div><p>The physical phenomena of nanofluid at high temperature motivate us to analyze problems with temperature-reliant fluid properties, like viscosity and thermal conductivity. Since in glass blowing, viscosity and thermal conductivity of the fluid may gets affected in such high temperature. This communication deals with the unsteady flow of nanofluid generated by nonlinear expansion of the surface. Temperature-dependent fluid viscosity and thermal conductivity are considered in the investigation of the problem. The flow of nanofluid is modeled using famous the <em>Buongiorno's two-phase</em> model, which includes the simultaneous effect of Brownian motion and thermophoresis diffusion. Appropriate transformations are adopted to obtain the ODEs from governing PDEs. Then MATLAB ‘bvp4c’ computation is used to solve the problem and to get a clear insight of the influences of various parameters. Graphical comparisons are made to check the accuracy of used numerical method. The study explores that heat transfer rate significantly enhances by the index of nonlinearity, variable viscosity and thermal conductivity parameters. Unsteadiness of the flow can be used as a controlling parameter to reduce the surface drag, heat and nano-mass transfer rate. Variable viscosity parameter leads to enhance the velocity near the surface and reducing the concentration of the nanoparticles. The thermal and concentration boundary layer thickens with thermal conductivity parameters. Nanofluid temperature and concentration of nanoparticles decay with nonlinear expanding index.</p></div>","PeriodicalId":73541,"journal":{"name":"JCIS open","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666934X22000228/pdfft?md5=b1fad3816767300453d94cff6ac96db9&pid=1-s2.0-S2666934X22000228-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41588285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-01DOI: 10.1016/j.jciso.2022.100069
Andrew T. Jacobson , Chen Chen , Janet C. Dewey , Grant C. Copeland , Wayne T. Allen , Bryony Richards , John P. Kaszuba , Adri C.T. van Duin , Hyeyoung Cho , Milind Deo , Yuqi She , Thomas P. Martin
Fluid-rock interactions may differ in mesopores (2–50 nm diameter) compared to macropores (>50 nm diameter). This study evaluates the influence of nano-confinement and pore geometry on point of zero charge (PZC) and hence surface charge and adsorption. PZC was determined for a suite of synthetic mesoporous amorphous silica materials and compared to the PZC of macroporous and non-porous amorphous silica. Reactive molecular dynamics simulations using ReaxFF determined surface equilibrium constants (pK) and clarified the large range of PZC values reported for macroporous and non-porous amorphous silica. Potentiometric titrations measured PZC and pK values of three mesoporous amorphous silica materials (SBA-15, SBA-16, and MCM-41) possessing a range of pore diameters (∼4–13 nm) and distinct pore geometries (cylindrical pores in a hexagonal lattice, spherical pores in a body-centered-cubic lattice, and hexagonal pores arranged in a hexagonal lattice); fluids were pre-saturated with silica to inhibit reaction with pore walls. Results are integrated with data from more than 150 published experimental studies. Neither nano-confinement nor pore geometry affects the PZC of the mesoporous amorphous silica materials. These results have implications for adsorption chemistry under confinement in mesoporous siliceous natural systems such as shales.
{"title":"Effect of nanoconfinement and pore geometry on point of zero charge in synthesized mesoporous siliceous materials","authors":"Andrew T. Jacobson , Chen Chen , Janet C. Dewey , Grant C. Copeland , Wayne T. Allen , Bryony Richards , John P. Kaszuba , Adri C.T. van Duin , Hyeyoung Cho , Milind Deo , Yuqi She , Thomas P. Martin","doi":"10.1016/j.jciso.2022.100069","DOIUrl":"10.1016/j.jciso.2022.100069","url":null,"abstract":"<div><p>Fluid-rock interactions may differ in mesopores (2–50 nm diameter) compared to macropores (>50 nm diameter). This study evaluates the influence of nano-confinement and pore geometry on point of zero charge (PZC) and hence surface charge and adsorption. PZC was determined for a suite of synthetic mesoporous amorphous silica materials and compared to the PZC of macroporous and non-porous amorphous silica. Reactive molecular dynamics simulations using ReaxFF determined surface equilibrium constants (<em>pK</em>) and clarified the large range of PZC values reported for macroporous and non-porous amorphous silica. Potentiometric titrations measured PZC and <em>pK</em> values of three mesoporous amorphous silica materials (SBA-15, SBA-16, and MCM-41) possessing a range of pore diameters (∼4–13 nm) and distinct pore geometries (cylindrical pores in a hexagonal lattice, spherical pores in a body-centered-cubic lattice, and hexagonal pores arranged in a hexagonal lattice); fluids were pre-saturated with silica to inhibit reaction with pore walls. Results are integrated with data from more than 150 published experimental studies. Neither nano-confinement nor pore geometry affects the PZC of the mesoporous amorphous silica materials. These results have implications for adsorption chemistry under confinement in mesoporous siliceous natural systems such as shales.</p></div>","PeriodicalId":73541,"journal":{"name":"JCIS open","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666934X22000277/pdfft?md5=a1e32114b29f53dee74bb69e03f5d8e1&pid=1-s2.0-S2666934X22000277-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42764295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-01DOI: 10.1016/j.jciso.2022.100056
Xueying Yu , Fang Cheng , Wei He
Microgel-mediated surface modification has shown great promises for a variety of metallic and non-metallic substrates. Yet, despite its compelling merits, this approach is less implemented on soft hydrogel substrates. Here, using the well-known bioinert agarose hydrogel as an example, we highlight a microgels-on-macrogel strategy that readily confers cytophilicity to the agarose surface toward anchorage-dependent cells. Specifically, we selected glycerol diglycidyl ether to tailor design polyetheramine-bisepoxide-based cationic microgels with more prominent ether alcohol features for enhanced chemical compatibility with agarose. Through a simple drop casting method, concurrent modifications of chemical, morphological and mechanical properties of the surface of agarose gel were then achieved with these microgels bound to the surface in a non-covalent yet robust manner. With the mere introduction of the cationic microgels, not only was the non-adhesive agarose surface effectively transformed to be cytophilic shown by the favorable responses from the in vitro culture of MC3T3-E1 cells, but also was hydrophobic reservoir function integrated conveniently. The demonstration of its feasibility and versatility warrants continued research of this straightforward microgels-on-macrogel strategy, which could be of value particularly for the development of novel biointerfaces.
{"title":"Microgels-on-macrogel: A simple cytophilic surface makeover of soft agarose substrates","authors":"Xueying Yu , Fang Cheng , Wei He","doi":"10.1016/j.jciso.2022.100056","DOIUrl":"10.1016/j.jciso.2022.100056","url":null,"abstract":"<div><p>Microgel-mediated surface modification has shown great promises for a variety of metallic and non-metallic substrates. Yet, despite its compelling merits, this approach is less implemented on soft hydrogel substrates. Here, using the well-known bioinert agarose hydrogel as an example, we highlight a microgels-on-macrogel strategy that readily confers cytophilicity to the agarose surface toward anchorage-dependent cells. Specifically, we selected glycerol diglycidyl ether to tailor design polyetheramine-bisepoxide-based cationic microgels with more prominent ether alcohol features for enhanced chemical compatibility with agarose. Through a simple drop casting method, concurrent modifications of chemical, morphological and mechanical properties of the surface of agarose gel were then achieved with these microgels bound to the surface in a non-covalent yet robust manner. With the mere introduction of the cationic microgels, not only was the non-adhesive agarose surface effectively transformed to be cytophilic shown by the favorable responses from the in vitro culture of MC3T3-E1 cells, but also was hydrophobic reservoir function integrated conveniently. The demonstration of its feasibility and versatility warrants continued research of this straightforward microgels-on-macrogel strategy, which could be of value particularly for the development of novel biointerfaces.</p></div>","PeriodicalId":73541,"journal":{"name":"JCIS open","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666934X22000149/pdfft?md5=7770595cfb3f696708266799256f07b0&pid=1-s2.0-S2666934X22000149-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47998796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-01DOI: 10.1016/j.jciso.2022.100058
Jessika Pazol , Thomas M. Weiss , Cristian D. Martínez , Orestes Quesada , Eduardo Nicolau
The chemical environment in aqueous solutions greatly influences the ability of amphiphilic molecules such as lipopolysaccharides (LPS) to aggregate into different structural phases in aqueous solutions. Understanding the substrate's morphology and conditions of aqueous solution that favor both enzymatic activity and the disruption of LPS aggregates are crucial in developing agents that can counteract the new trend of multidrug resistance by gram-negative bacteria. In this study, we developed two LPS morphologies using LPS from Escherichia coli as a model to study the in vitro hydrolytic response when using a lipase treatment. The hydrolysis was performed using lipase b from Candida antarctica to understand the catalytic effect in removing fatty acids from its lipid A moiety on different LPS aggregates. Physical and chemical characterizations of the products included dynamic light scattering, small angle X-ray scattering, Fourier transform infrared spectroscopy, thin-layer chromatography, and gas chromatography. Our results suggest a trend of prominent hydrolytic response (72% enhancement) upon the addition of calcium ions to induce LPS aggregates into bilayer formations. Moreover, our results revealed the detection of myristic acid (C14:0) as the product of the hydrolysis when using RaLPS in its aggregate forms.
{"title":"The influence of calcium ions (Ca2+) on the enzymatic hydrolysis of lipopolysaccharide aggregates to liberate free fatty acids (FFA) in aqueous solution","authors":"Jessika Pazol , Thomas M. Weiss , Cristian D. Martínez , Orestes Quesada , Eduardo Nicolau","doi":"10.1016/j.jciso.2022.100058","DOIUrl":"10.1016/j.jciso.2022.100058","url":null,"abstract":"<div><p>The chemical environment in aqueous solutions greatly influences the ability of amphiphilic molecules such as lipopolysaccharides (LPS) to aggregate into different structural phases in aqueous solutions. Understanding the substrate's morphology and conditions of aqueous solution that favor both enzymatic activity and the disruption of LPS aggregates are crucial in developing agents that can counteract the new trend of multidrug resistance by gram-negative bacteria. In this study, we developed two LPS morphologies using LPS from <em>Escherichia coli</em> as a model to study the <em>in vitro</em> hydrolytic response when using a lipase treatment. The hydrolysis was performed using lipase b from <em>Candida antarctica</em> to understand the catalytic effect in removing fatty acids from its lipid A moiety on different LPS aggregates. Physical and chemical characterizations of the products included dynamic light scattering, small angle X-ray scattering, Fourier transform infrared spectroscopy, thin-layer chromatography, and gas chromatography. Our results suggest a trend of prominent hydrolytic response (72% enhancement) upon the addition of calcium ions to induce LPS aggregates into bilayer formations. Moreover, our results revealed the detection of myristic acid (C14:0) as the product of the hydrolysis when using RaLPS in its aggregate forms.</p></div>","PeriodicalId":73541,"journal":{"name":"JCIS open","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/dd/2e/nihms-1877286.PMC10433262.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10421857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-01DOI: 10.1016/j.jciso.2022.100059
Mohammad Shakourian , Saeed Rahemi Ardekani , Amir Bayat , Esmaiel Saievar-Iranizad , Wim Deferme
A stable self-cleaning superhydrophobic coating with reliable corrosion resistance was coated on the aluminum alloy 6061. A dense polyvinylidene fluoride (PVDF) layer was first coated by the doctor blade method, and hydrolyzed methyltrimethoxysilane (HMTMS) nanospheres were then deposited on top of the PVDF using ultrasonic spray hydrolysis technique. Superhydrophobic coatings with a contact angle (CA) of 167° and a sliding angle of 7 ± 1° were obtained. The superhydrophobic coating exhibited self-cleaning behavior. The corrosion resistance of the layers was investigated in a 3.5 wt% NaCl aqueous solution using potentiodynamic polarization measurement and electrochemical impedance spectroscopy techniques, indicating the high corrosion resistance of the flat PVDF barrier and the excellent resistance of the superhydrophobic coating. The charge transfer resistance of the bare aluminum substrate measured as 6.572 kΩ cm2 increased to 848.463 kΩ cm2 and 3.411 × 103 kΩ cm2 with PVDF and HMTMS, respectively. The results showed that a proper superhydrophobic coating with good chemical stability could significantly increase the corrosion resistance of the substrate. We also showed the capability of the novel ultrasonic spray hydrolysis technique in fabricating stable superhydrophobic films for large-scale applications.
{"title":"Ultrasonic atomization based fabrication of superhydrophobic and corrosion-resistant hydrolyzed MTMS/PVDF coatings","authors":"Mohammad Shakourian , Saeed Rahemi Ardekani , Amir Bayat , Esmaiel Saievar-Iranizad , Wim Deferme","doi":"10.1016/j.jciso.2022.100059","DOIUrl":"10.1016/j.jciso.2022.100059","url":null,"abstract":"<div><p>A stable self-cleaning superhydrophobic coating with reliable corrosion resistance was coated on the aluminum alloy 6061. A dense polyvinylidene fluoride (PVDF) layer was first coated by the doctor blade method, and hydrolyzed methyltrimethoxysilane (HMTMS) nanospheres were then deposited on top of the PVDF using ultrasonic spray hydrolysis technique. Superhydrophobic coatings with a contact angle (CA) of 167° and a sliding angle of 7 ± 1° were obtained. The superhydrophobic coating exhibited self-cleaning behavior. The corrosion resistance of the layers was investigated in a 3.5 wt% NaCl aqueous solution using potentiodynamic polarization measurement and electrochemical impedance spectroscopy techniques, indicating the high corrosion resistance of the flat PVDF barrier and the excellent resistance of the superhydrophobic coating. The charge transfer resistance of the bare aluminum substrate measured as 6.572 kΩ cm<sup>2</sup> increased to 848.463 kΩ cm<sup>2</sup> and 3.411 × 10<sup>3</sup> kΩ cm<sup>2</sup> with PVDF and HMTMS, respectively. The results showed that a proper superhydrophobic coating with good chemical stability could significantly increase the corrosion resistance of the substrate. We also showed the capability of the novel ultrasonic spray hydrolysis technique in fabricating stable superhydrophobic films for large-scale applications.</p></div>","PeriodicalId":73541,"journal":{"name":"JCIS open","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666934X22000174/pdfft?md5=1feab1c45b15bc269eaa3df5e8c619d8&pid=1-s2.0-S2666934X22000174-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44962780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-01DOI: 10.1016/j.jciso.2022.100057
Elena S. Kartashynska , Dieter Vollhardt
The quantum chemical approach and a thermodynamic model for amphiphilic monolayers are used to find the temperature dependence of the area per amphiphile molecule in a monolayer at the onset of liquid-expanded – liquid-condensed phase transition (Ac). Quantum chemical calculations within the semiempiric PM3 method for clusterization thermodynamics and structure of surfactant dimers and trimers are used, as well as for assessment of their molecular area in an aggregate. Calculations are done for seven amphiphile classes: saturated and ethoxylated alcohols, saturated and unsaturated carboxylic acids, α-hydroxylic acids, N-acyl-substituted alanine and dialkyl-substituted melamine that are well experimentally explored. Calculations reflect the experimental data and show that a temperature increase leads to decrease of Ac for an amphiphile with a given alkyl chain length, and vice versa with a chain length increase at a fixed temperature the Ac value grows. It was shown that as the temperature increases the increment of Ac per methylene unit of the hydrocarbon chain becomes less significant. The average values of the slope reflecting the change of Ac per 1 °C for saturated and ethoxylated alcohols, saturated, cis- and trans-unsaturated carboxylic acids, α-hydroxylic acids, N-acyl-substituted alanine and dialkyl-substituted melamine are 0.57, 1.32, 1.14, 1.26, 1.15, 0.66, 1.07 and 0.67 Å2/°С, respectively. These data are quite similar to the experimental values of for tetradecanoic acid, dipalmitoyl-phosphatidylcholine and dipalmitoyl phosphatididic acid. The proposed approach can be used as a predictive tool for amphiphiles lacking experimental data.
{"title":"Molecular area dependences of monolayers at the air/water interface","authors":"Elena S. Kartashynska , Dieter Vollhardt","doi":"10.1016/j.jciso.2022.100057","DOIUrl":"10.1016/j.jciso.2022.100057","url":null,"abstract":"<div><p>The quantum chemical approach and a thermodynamic model for amphiphilic monolayers are used to find the temperature dependence of the area per amphiphile molecule in a monolayer at the onset of liquid-expanded – liquid-condensed phase transition (A<sub>c</sub>). Quantum chemical calculations within the semiempiric PM3 method for clusterization thermodynamics and structure of surfactant dimers and trimers are used, as well as for assessment of their molecular area in an aggregate. Calculations are done for seven amphiphile classes: saturated and ethoxylated alcohols, saturated and unsaturated carboxylic acids, α-hydroxylic acids, <em>N</em>-acyl-substituted alanine and dialkyl-substituted melamine that are well experimentally explored. Calculations reflect the experimental data and show that a temperature increase leads to decrease of A<sub>c</sub> for an amphiphile with a given alkyl chain length, and vice versa with a chain length increase at a fixed temperature the A<sub>c</sub> value grows. It was shown that as the temperature increases the increment of A<sub>c</sub> per methylene unit of the hydrocarbon chain becomes less significant. The average values of the slope reflecting the change of A<sub>c</sub> per 1 °C for saturated and ethoxylated alcohols, saturated, <em>cis</em>- and <em>trans</em>-unsaturated carboxylic acids, α-hydroxylic acids, <em>N</em>-acyl-substituted alanine and dialkyl-substituted melamine are 0.57, 1.32, 1.14, 1.26, 1.15, 0.66, 1.07 and 0.67 Å<sup>2</sup>/°С, respectively. These data are quite similar to the experimental values of <span><math><mrow><mo>−</mo><mfrac><mrow><mi>d</mi><msub><mi>A</mi><mi>c</mi></msub></mrow><mrow><mi>d</mi><mi>T</mi></mrow></mfrac></mrow></math></span> for tetradecanoic acid, dipalmitoyl-phosphatidylcholine and dipalmitoyl phosphatididic acid. The proposed approach can be used as a predictive tool for amphiphiles lacking experimental data.</p></div>","PeriodicalId":73541,"journal":{"name":"JCIS open","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666934X22000150/pdfft?md5=6298d3dbf0314be231dcd5b10bdae763&pid=1-s2.0-S2666934X22000150-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47304648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Effect of 1-butyl-3-methylimidazolium chloride ionic liquid ([bmim]Cl, IL) on the monolayer/bilayer of either soy-phosphatidylcholine (SPC) or hydrogenated soy-phosphatidylcholine (HSPC), in combination with 30 mol% cholesterol (Chol), were investigated. Impact of IL on monolayers were explored by measuring the surface pressure (π)-area (A) isotherm with a Langmuir-surface balance. Lift-off area (A0) of the monomolecular films gradually increased [A0(HSPC+IL) > A0(SPC+IL)], collapse pressures (πc) decreased and passed through minima [πc(HSPC+IL) > πc(SPC+IL)] with increasing IL concentration ([IL]). Minimum molecular area (Amin) increased monotonously and compression moduli (Cs−1) followed the sequence (HSPC+IL) > (SPC+IL) at a particular π with respect to [IL]. Dynamic light scattering studies were carried out to determine the hydrodynamic diameter (dh), zeta potential (Z.P.) and polydispersity index (PDI) values while fluorescence anisotropy studies, using 7-hydroxycoumarin and 1,6-diphenyl-1,3,5-hexatriene, could reveal the micro-viscosity of liposomes. Increased size and rigidity, induced by IL, suggest the formation of leak-proof, condensed liposomes. Disruption of vesicles induced by IL were observed from transmission electron microscopic (TEM) studies. IL induced disintegration of liposome and kinetics of subsequent formation of adsorbed monolayer were accomplished by surface pressure-time isotherms. IL-induced liposomes were substantially less toxic as revealed by MTT assay. These liposomes are considered to be safely used as effective and controlled drug delivery systems.
{"title":"Investigations on the role of ionic liquid on the physicochemical characteristics and toxicological consequences of liposomes","authors":"Manas Kumar Mandal , Emili Manna , Habiba Sultana , Manas Barai , Kartik Chandra Guchhait , Chandradipa Ghosh , Anuttam Patra , Kaushik Nag , Shin-ichi Yusa , Amiya Kumar Panda","doi":"10.1016/j.jciso.2022.100050","DOIUrl":"10.1016/j.jciso.2022.100050","url":null,"abstract":"<div><p>Effect of 1-butyl-3-methylimidazolium chloride ionic liquid ([bmim]Cl, IL) on the monolayer/bilayer of either soy-phosphatidylcholine (SPC) or hydrogenated soy-phosphatidylcholine (HSPC), in combination with 30 mol% cholesterol (Chol), were investigated. Impact of IL on monolayers were explored by measuring the surface pressure (<em>π</em>)-area (<em>A</em>) isotherm with a Langmuir-surface balance. Lift-off area (<em>A</em><sub>0</sub>) of the monomolecular films gradually increased [<em>A</em><sub>0(HSPC+IL)</sub> > <em>A</em><sub>0(SPC+IL)</sub>], collapse pressures (<em>π</em><sub>c</sub>) decreased and passed through minima [<em>π</em><sub>c(HSPC+IL)</sub> > <em>π</em><sub>c(SPC+IL)</sub>] with increasing IL concentration ([IL]). Minimum molecular area (<em>A</em><sub>min</sub>) increased monotonously and compression moduli (<em>C</em><sub><em>s</em></sub><sup>−1</sup>) followed the sequence (HSPC+IL) > (SPC+IL) at a particular <em>π</em> with respect to [IL]. Dynamic light scattering studies were carried out to determine the hydrodynamic diameter (<em>d</em><sub>h</sub>), zeta potential (<em>Z.P.</em>) and polydispersity index (<em>PDI</em>) values while fluorescence anisotropy studies, using 7-hydroxycoumarin and 1,6-diphenyl-1,3,5-hexatriene, could reveal the micro-viscosity of liposomes. Increased size and rigidity, induced by IL, suggest the formation of leak-proof, condensed liposomes. Disruption of vesicles induced by IL were observed from transmission electron microscopic (TEM) studies. IL induced disintegration of liposome and kinetics of subsequent formation of adsorbed monolayer were accomplished by surface pressure-time isotherms. IL-induced liposomes were substantially less toxic as revealed by MTT assay. These liposomes are considered to be safely used as effective and controlled drug delivery systems.</p></div>","PeriodicalId":73541,"journal":{"name":"JCIS open","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666934X22000083/pdfft?md5=b3c031b8bc57faa170728c813422837f&pid=1-s2.0-S2666934X22000083-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46542317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-01DOI: 10.1016/j.jciso.2022.100052
Matthäus Barasinski , Carsten Schilde , Sebastian Melzig , Merle Hübner , Georg Garnweitner , Sabrina Zellmer
In order to enhance the quality of spray-dried products or to adjust material properties for new applications, precise control of the aggregate structure is desirable. For the purpose of preparing hierarchically structured aggregates in the micrometer range, the formulation of the suspension can be specifically designed, utilizing defined nanoparticulate building blocks to achieve a highly uniform structure and porosity. Further adjustments can be made by combining two types of primary particles that differ in size. Thereby, a segregation effect is observed, where nanoparticles with larger particle sizes accumulate rather within the core of an aggregate and those with smaller particle sizes gather mainly near the outer surface, resulting in the formation of a shell. Furthermore, it is possible to produce tailor-made porosities using template particles (e.g. polystyrene) of different sizes as part of the coarse and fine fractions. The removal of these particles by a subsequent tempering process can lead to aggregates with defined porous structures and thus, to different mechanical aggregate properties that can be specifically set by adjusting the process and formulation parameters. As a result, a promising building kit for the hierarchically structure formation via spray drying processes were achieved.
For the detailed characterization structural and mechanical material properties were investigated, using e.g. mercury intrusion and SEM. The influence of the formulation parameters of the suspension (primary particle size and template content) on the micromechanical properties of the aggregate structures was systematically investigated by nanoindentation to elucidate structure-property relationships regarding, for example elastic and plastic deformation. As a result, a correlation could be established between the experimentally determined mechanical parameters and the aggregate porosities.
Such microstructures with defined properties can be used in a variety of applications, including catalysis or as drug carriers. For instance, these spray-dried aggregates were loaded with ibuprofen as an exemplary active pharmaceutical ingredient and investigated with regard to their drug release behavior.
{"title":"Micromechanical properties of spray-dried core-shell silica aggregates along with drug release tests","authors":"Matthäus Barasinski , Carsten Schilde , Sebastian Melzig , Merle Hübner , Georg Garnweitner , Sabrina Zellmer","doi":"10.1016/j.jciso.2022.100052","DOIUrl":"10.1016/j.jciso.2022.100052","url":null,"abstract":"<div><p>In order to enhance the quality of spray-dried products or to adjust material properties for new applications, precise control of the aggregate structure is desirable. For the purpose of preparing hierarchically structured aggregates in the micrometer range, the formulation of the suspension can be specifically designed, utilizing defined nanoparticulate building blocks to achieve a highly uniform structure and porosity. Further adjustments can be made by combining two types of primary particles that differ in size. Thereby, a segregation effect is observed, where nanoparticles with larger particle sizes accumulate rather within the core of an aggregate and those with smaller particle sizes gather mainly near the outer surface, resulting in the formation of a shell. Furthermore, it is possible to produce tailor-made porosities using template particles (e.g. polystyrene) of different sizes as part of the coarse and fine fractions. The removal of these particles by a subsequent tempering process can lead to aggregates with defined porous structures and thus, to different mechanical aggregate properties that can be specifically set by adjusting the process and formulation parameters. As a result, a promising building kit for the hierarchically structure formation via spray drying processes were achieved.</p><p>For the detailed characterization structural and mechanical material properties were investigated, using e.g. mercury intrusion and SEM. The influence of the formulation parameters of the suspension (primary particle size and template content) on the micromechanical properties of the aggregate structures was systematically investigated by nanoindentation to elucidate structure-property relationships regarding, for example elastic and plastic deformation. As a result, a correlation could be established between the experimentally determined mechanical parameters and the aggregate porosities.</p><p>Such microstructures with defined properties can be used in a variety of applications, including catalysis or as drug carriers. For instance, these spray-dried aggregates were loaded with ibuprofen as an exemplary active pharmaceutical ingredient and investigated with regard to their drug release behavior.</p></div>","PeriodicalId":73541,"journal":{"name":"JCIS open","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666934X22000101/pdfft?md5=08cbe6160eba2117836b718916e5947a&pid=1-s2.0-S2666934X22000101-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44110984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}