An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quan- titatively estimate the interfacial energy of the nanostructured multilayer films (NMFs) adherent to flexi...An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quan- titatively estimate the interfacial energy of the nanostructured multilayer films (NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be ~ 5.0 J/m2 for Cu/Cr, ~4.1 J/m2 for Cu/Ta, ~ 2.8 J/m2 for Cu/Mo, ~ 1.1 J/m2 for Cu/Nb, and ~ 1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.展开更多
In order to clarify the edge and interface effect on the adhesion energy between graphene(Gr)and its substrate,a theoretical model is proposed to study the interaction and strain distribution of Gr/Si system in terms ...In order to clarify the edge and interface effect on the adhesion energy between graphene(Gr)and its substrate,a theoretical model is proposed to study the interaction and strain distribution of Gr/Si system in terms of continuum medium mechanics and nanothermodynamics.We find that the interface separation and adhesion energy are determined by the thickness of Gr and substrate.The disturbed interaction and redistributed strain in the Gr/Si system induced by the effect of surface and interface can make the interface adhesion energy decrease with increasing thickness of Gr and diminishing thickness of Si.Moreover,our results show that the smaller area of Gr is more likely to adhere to the substrate since the edge effect improves the active energy and strain energy.Our predictions can be expected to be a guide for designing high performance of Grbased electronic devices.展开更多
The anti-bacterial adhesion properties of TiO2-coated polymethyl methacrylate (PMMA) surfaces are investigated systematically. In detail, the adhesion of S. aureus (gram positive) and E. coli (gram negative) to ...The anti-bacterial adhesion properties of TiO2-coated polymethyl methacrylate (PMMA) surfaces are investigated systematically. In detail, the adhesion of S. aureus (gram positive) and E. coli (gram negative) to TiO2-coated and uncoated PMMA surfaces are performed by the plate counting method. Afterwards, the adhesion free energy of bacteria on both supporting materials is quantified using the thermodynamic approach of Lifshitz van der Waals and acid/base interactions. The superior anti-adhesion capability of TiO2-coated PMMA is demonstrated when compared to native PMMA, both experimentally and theoretically.展开更多
A possible relationship between Schottky barrier heights and adhesion energies of different nonreactivemetal/semiconductor or insulator interfaces is presented .Various experimental evidences further sup-porting such ...A possible relationship between Schottky barrier heights and adhesion energies of different nonreactivemetal/semiconductor or insulator interfaces is presented .Various experimental evidences further sup-porting such a relationship are briefly exploited. The consequence indicated by such a relationship on the understanding of metal / ceramic interfaces is stressed.展开更多
The thermodynamic adhesion between a metal and a ceramic crystal was believed to be the result of theelectron transfer from the metal into the cerainic crystal. From an electronic point of view, such an electrontransf...The thermodynamic adhesion between a metal and a ceramic crystal was believed to be the result of theelectron transfer from the metal into the cerainic crystal. From an electronic point of view, such an electrontransfer at the metal/ceramic interface may be represented by the tunnelling of the metal conduction electron into the ceramic bandgap. Theoretical analysis of the quantum tunnelling process at an intimate rnetal-semicon-ductor contact were performed . and the relationship between adhesion energies and Schottky barrier heights ofvarious metal/semiconductor or insulator interfaces was dcduced .展开更多
To study the wall-sticking phenomenon and prevent pipeline blockage accidents,two analytical methods are used to evaluate the influence of different crude oil components on the wall-sticking occurrence temperature(WSO...To study the wall-sticking phenomenon and prevent pipeline blockage accidents,two analytical methods are used to evaluate the influence of different crude oil components on the wall-sticking occurrence temperature(WSOT).The WSOT and the interactions among oil,water,and surface solids are measured and calculated by various devices under different values of the wax content,water pH,and salinity.The results show that there is greater correlation between the wax content and WSOT than between resins/asphaltenes and WSOT.Furthermore,the wax content,water pH,and salinity have different effects on WSOT.There is generally a positive correlation between wax content and WSOT,whereas the maximum WSOT occurs when the water pH is in the range 5.7–6.5,and decreases under more acidic or alkaline conditions.As the salinity increases,WSOT decreases slightly,but quickly becomes saturated.In terms of interactions,variations in the interfacial tension and adhesion work with pH and salinity are consistent with that of WSOT,while the contact angle exhibits the opposite relation.展开更多
6H-SiC (1010) surface and Si (220)/6H-SIC (1010) interface with different stacking sites are investigated using first-principles calculations. Surface energies of 6H-SiC (1010) (case I, case II, and case III...6H-SiC (1010) surface and Si (220)/6H-SIC (1010) interface with different stacking sites are investigated using first-principles calculations. Surface energies of 6H-SiC (1010) (case I, case II, and case III) are firstly studied and the surface calculation results show that case II and case III are more stable than case I. Then, the adhesion energies, fracture toughness values, interfacial energies, densities of states, and electronic structures of Si (220)/6H-SIC (1010) interfaces for three stacking models (AM, BM, and CM) are calculated. The CM model has the highest adhesion energy and the lowest interracial energy, suggesting that the CM is stronger and more thermodynamically stable than AM and BM. Densities of states and the total charge densities give evidence that interfacial bonding is formed at the interface and that Si-Si and Si-C are induced due to the hybridization of C-2p and Si-3p. Moreover, the Si-C is much stronger than Si-Si at the interface, implying that the contribution of the interfacial bonding mainly comes from Si-C rather than Si-Si.展开更多
Up to now, it is always a delicate and challenging task to clean and protect Xuan paper ink painting. Xuan paper is composed of cellulose with a rough surface and easy to absorb dust, which leads to poor cleaning effe...Up to now, it is always a delicate and challenging task to clean and protect Xuan paper ink painting. Xuan paper is composed of cellulose with a rough surface and easy to absorb dust, which leads to poor cleaning effect and irreversible damage in traditional cleaning process. Hydrogel is one of the most effective tools to clean the artworks. However, in the practice of cleaning Xuan paper, most hydrogels cannot achieve fine cleaning result due to the interfacial adhesion issues. Herein, to protectively and effectively clean Xuan paper, using physical yet strong poly(vinyl alcohol)/poly(N-(2-hydroxyethyl) acrylamide)(PVA/PHEAA)hydrogel with suitable stiffness as the model, the interfacial adhesion between hydrogel and Xuan paper was systematically investigated, and various technologies were used to evaluate the cleaning effect. A critical interfacial adhesive energy(< 4 J/m^(2))is found to achieve the protective and effective cleaning purpose. To the best of our knowledge, this is the first report to estimate the adhesion of hydrogel on the cleaning of paper artwork, which will provide a new viewport in the conservation practice.展开更多
To further detem3ine the fouling behavior of bovine serum albumin (BSA) on different hydrophilic PVDF ultrafiltration (UF) membranes over a range of pH values, self-made atomic force microscopy (AFM) colloidal p...To further detem3ine the fouling behavior of bovine serum albumin (BSA) on different hydrophilic PVDF ultrafiltration (UF) membranes over a range of pH values, self-made atomic force microscopy (AFM) colloidal probes were used to detect the adhesion forces of membrane-BSA and BSA BSA, respectively. Results showed that the membrane-BSA adhesion interaction was stronger than the BSA-BSA adhesion interaction, and the adhesion force between BSA-BSA-fouled PVDF/PVA membranes was similar to that between BSA-BSA-fouled PVDF/PVP membranes, which indicated that the fouling was mainly caused by the adhesion interaction between membrane and BSA. At the same pH condition, the PVDF/PVA membrane-BSA adhesion force was smaller than that of PVDF/ PVP membrane-BSA, which illustrated that the more hydrophilic the membrane was, the better antifouling ability it had. The extended Derjaguin-Landau-Verwey Overbeek (XDLVO) theory predicts that the polar or Lewis acid-base (AB) interaction played a dominant role in the interracial free energy ofmcmbrane-BSA and BSA BSA that can be affected by pH. For the same membrane, the pH values of a BSA solution can have a significant impact on the process of membrane fouling by changing the AB component of free energy.展开更多
Deep bed filtration in aqueous media is a well-known process for solid-liquid separation. However, the use of deep bed filtration for the purification of metal melts is a relatively new field of application, In partic...Deep bed filtration in aqueous media is a well-known process for solid-liquid separation. However, the use of deep bed filtration for the purification of metal melts is a relatively new field of application, In particular, the separation mechanism of metal melts filtration is a new area for investigation. The current paper aims at examining the influence of wetting on the filtration efficiency of ceramic foam filters that is an important feature of the metal melts filtration process. A model system was designed using water and alumina particles (〈200μm). The particles and filter medium were coated to model poor wetting. Thus, examination of the influence of wetting on the adhesion energy and filtration performance was possible. Furthermore, the effect of fluid velocity was studied. To this end, the experiments were carried out under atmospheric conditions and at 20℃. The findings showed that poor wetting between the fluid and solid phase significantly increased the filtration efficiency.展开更多
The purpose of this work is in development of the model that allows to investigate the conformations of macromolecules near the interface"dielectric-metal"depending on the conditions of formation of the poly...The purpose of this work is in development of the model that allows to investigate the conformations of macromolecules near the interface"dielectric-metal"depending on the conditions of formation of the polymer coating.In the modified model of"sticky tape",one part of macromolecule is anchored to the metal surface while the other can be elongated due to effective mean(molecular)field of dipolar type formed by free ends of other chains.The dynamic Monte-Carlo method for Langmuir's model is used for calculation of adhesion force taking into account the interaction energy of monomers with the metal surface.It is shown that conformation of polymer chain is defined by temperature conditions of its formation.The obtained results are confirmed by the data of production tests on polymer coatings in JSC"Severstal".展开更多
We investigated the influence of particle shape and solubility on the caking behavior of trisodium phosphate by considering the adhesion free energy and crystal bridge theory. Caking of trisodium phosphate during the ...We investigated the influence of particle shape and solubility on the caking behavior of trisodium phosphate by considering the adhesion free energy and crystal bridge theory. Caking of trisodium phosphate during the drying process under static conditions is a two-step process: adhesion followed by crystal bridge formation between particles. The adhesion free energy plays an important role in adhesion. Trisodium phosphate particles cannot adhere to each other and cake when the adhesion free energy is greater than a critical value, which varies with particle shape. Compared with granular particles, cylindrical particles have larger contact area between particles, which results in more crystal bridges forming and a higher caking ratio. Thus, the critical value is about 100 mJ/m^2 for cylindrical particles, but 60 mJ/m^2 for granular particles at 25 ℃. Concerning the solubility, when particles are similar shapes and soluble in the rinsing liquid, the caking ratio has a linear relationship with adhesion free energy. However, if the particles are insoluble in the rinsing liquid, caking can be completely prevented regardless of adhesion free energy because no crystal bridges form during the growth process. Hence, caking of trisodium phosphate particles could be inhibited by screening rinsing liquids, and optimizing the particle shape and size distribution.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.5132100351322104+6 种基金51201123 and 51571157)the National Basic Research Program of China(No.2010CB631003)the 111 Project of China(No.B06025)the support from Fundamental Research Funds for the Central UniversitiesTengfei Scholar projectChina Postdoctoral Science Foundation(No.2012M521765)Shaanxi Province Postdoctoral Scientific Research Projects for part of financial support
文摘An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quan- titatively estimate the interfacial energy of the nanostructured multilayer films (NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be ~ 5.0 J/m2 for Cu/Cr, ~4.1 J/m2 for Cu/Ta, ~ 2.8 J/m2 for Cu/Mo, ~ 1.1 J/m2 for Cu/Nb, and ~ 1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.
基金This work was supported by the Natural Science Foundation of Guangdong Province(Grant Nos.2019A1515010916 and 2018A030307028)the Featured Innovation Project of Guangdong Education Department(2018KTSCX150)+1 种基金the Maoming Natural Science Foundation of Guangdong,China,(Grant No.2019018001)the Guangdong Province Major Foundation of Fundamental Research(Grant No.517042).
文摘In order to clarify the edge and interface effect on the adhesion energy between graphene(Gr)and its substrate,a theoretical model is proposed to study the interaction and strain distribution of Gr/Si system in terms of continuum medium mechanics and nanothermodynamics.We find that the interface separation and adhesion energy are determined by the thickness of Gr and substrate.The disturbed interaction and redistributed strain in the Gr/Si system induced by the effect of surface and interface can make the interface adhesion energy decrease with increasing thickness of Gr and diminishing thickness of Si.Moreover,our results show that the smaller area of Gr is more likely to adhere to the substrate since the edge effect improves the active energy and strain energy.Our predictions can be expected to be a guide for designing high performance of Grbased electronic devices.
基金Supported by the Program for Changjiang Scholars and Innovative Research Team in University (PCSIR0818)Health Ministry Foundation of China (WKJ2005-2-003)Natural Science Foundation of Fujian Province (2008H0089 and 2009J01025)
文摘The anti-bacterial adhesion properties of TiO2-coated polymethyl methacrylate (PMMA) surfaces are investigated systematically. In detail, the adhesion of S. aureus (gram positive) and E. coli (gram negative) to TiO2-coated and uncoated PMMA surfaces are performed by the plate counting method. Afterwards, the adhesion free energy of bacteria on both supporting materials is quantified using the thermodynamic approach of Lifshitz van der Waals and acid/base interactions. The superior anti-adhesion capability of TiO2-coated PMMA is demonstrated when compared to native PMMA, both experimentally and theoretically.
文摘A possible relationship between Schottky barrier heights and adhesion energies of different nonreactivemetal/semiconductor or insulator interfaces is presented .Various experimental evidences further sup-porting such a relationship are briefly exploited. The consequence indicated by such a relationship on the understanding of metal / ceramic interfaces is stressed.
文摘The thermodynamic adhesion between a metal and a ceramic crystal was believed to be the result of theelectron transfer from the metal into the cerainic crystal. From an electronic point of view, such an electrontransfer at the metal/ceramic interface may be represented by the tunnelling of the metal conduction electron into the ceramic bandgap. Theoretical analysis of the quantum tunnelling process at an intimate rnetal-semicon-ductor contact were performed . and the relationship between adhesion energies and Schottky barrier heights ofvarious metal/semiconductor or insulator interfaces was dcduced .
基金supported by the National Natural Science Foundation of China(NNFC,Grant No.51534007).
文摘To study the wall-sticking phenomenon and prevent pipeline blockage accidents,two analytical methods are used to evaluate the influence of different crude oil components on the wall-sticking occurrence temperature(WSOT).The WSOT and the interactions among oil,water,and surface solids are measured and calculated by various devices under different values of the wax content,water pH,and salinity.The results show that there is greater correlation between the wax content and WSOT than between resins/asphaltenes and WSOT.Furthermore,the wax content,water pH,and salinity have different effects on WSOT.There is generally a positive correlation between wax content and WSOT,whereas the maximum WSOT occurs when the water pH is in the range 5.7–6.5,and decreases under more acidic or alkaline conditions.As the salinity increases,WSOT decreases slightly,but quickly becomes saturated.In terms of interactions,variations in the interfacial tension and adhesion work with pH and salinity are consistent with that of WSOT,while the contact angle exhibits the opposite relation.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61076011 and 51177134)
文摘6H-SiC (1010) surface and Si (220)/6H-SIC (1010) interface with different stacking sites are investigated using first-principles calculations. Surface energies of 6H-SiC (1010) (case I, case II, and case III) are firstly studied and the surface calculation results show that case II and case III are more stable than case I. Then, the adhesion energies, fracture toughness values, interfacial energies, densities of states, and electronic structures of Si (220)/6H-SIC (1010) interfaces for three stacking models (AM, BM, and CM) are calculated. The CM model has the highest adhesion energy and the lowest interracial energy, suggesting that the CM is stronger and more thermodynamically stable than AM and BM. Densities of states and the total charge densities give evidence that interfacial bonding is formed at the interface and that Si-Si and Si-C are induced due to the hybridization of C-2p and Si-3p. Moreover, the Si-C is much stronger than Si-Si at the interface, implying that the contribution of the interfacial bonding mainly comes from Si-C rather than Si-Si.
基金supported by the Excellent Youth Fund Project of Henan Natural Science Foundation(Grant No.202300410166)the Major Project of Wenzhou Institute,University of Chinese Academy of Sciences(Grant Nos.WIUCASQD2021004 and WIUCASQD2021035)the National Natural Science Foundation of China(Grant Nos.21504022 and 22202051)。
文摘Up to now, it is always a delicate and challenging task to clean and protect Xuan paper ink painting. Xuan paper is composed of cellulose with a rough surface and easy to absorb dust, which leads to poor cleaning effect and irreversible damage in traditional cleaning process. Hydrogel is one of the most effective tools to clean the artworks. However, in the practice of cleaning Xuan paper, most hydrogels cannot achieve fine cleaning result due to the interfacial adhesion issues. Herein, to protectively and effectively clean Xuan paper, using physical yet strong poly(vinyl alcohol)/poly(N-(2-hydroxyethyl) acrylamide)(PVA/PHEAA)hydrogel with suitable stiffness as the model, the interfacial adhesion between hydrogel and Xuan paper was systematically investigated, and various technologies were used to evaluate the cleaning effect. A critical interfacial adhesive energy(< 4 J/m^(2))is found to achieve the protective and effective cleaning purpose. To the best of our knowledge, this is the first report to estimate the adhesion of hydrogel on the cleaning of paper artwork, which will provide a new viewport in the conservation practice.
文摘To further detem3ine the fouling behavior of bovine serum albumin (BSA) on different hydrophilic PVDF ultrafiltration (UF) membranes over a range of pH values, self-made atomic force microscopy (AFM) colloidal probes were used to detect the adhesion forces of membrane-BSA and BSA BSA, respectively. Results showed that the membrane-BSA adhesion interaction was stronger than the BSA-BSA adhesion interaction, and the adhesion force between BSA-BSA-fouled PVDF/PVA membranes was similar to that between BSA-BSA-fouled PVDF/PVP membranes, which indicated that the fouling was mainly caused by the adhesion interaction between membrane and BSA. At the same pH condition, the PVDF/PVA membrane-BSA adhesion force was smaller than that of PVDF/ PVP membrane-BSA, which illustrated that the more hydrophilic the membrane was, the better antifouling ability it had. The extended Derjaguin-Landau-Verwey Overbeek (XDLVO) theory predicts that the polar or Lewis acid-base (AB) interaction played a dominant role in the interracial free energy ofmcmbrane-BSA and BSA BSA that can be affected by pH. For the same membrane, the pH values of a BSA solution can have a significant impact on the process of membrane fouling by changing the AB component of free energy.
基金the German Research Foundation(DFG) for supporting the studies in the sub-project BO1,which is part of the Collaborative Research Center CRC 920
文摘Deep bed filtration in aqueous media is a well-known process for solid-liquid separation. However, the use of deep bed filtration for the purification of metal melts is a relatively new field of application, In particular, the separation mechanism of metal melts filtration is a new area for investigation. The current paper aims at examining the influence of wetting on the filtration efficiency of ceramic foam filters that is an important feature of the metal melts filtration process. A model system was designed using water and alumina particles (〈200μm). The particles and filter medium were coated to model poor wetting. Thus, examination of the influence of wetting on the adhesion energy and filtration performance was possible. Furthermore, the effect of fluid velocity was studied. To this end, the experiments were carried out under atmospheric conditions and at 20℃. The findings showed that poor wetting between the fluid and solid phase significantly increased the filtration efficiency.
基金The study results are obtained at the performance of State Task No.2014/267 from 31.01.2014,No.1715.
文摘The purpose of this work is in development of the model that allows to investigate the conformations of macromolecules near the interface"dielectric-metal"depending on the conditions of formation of the polymer coating.In the modified model of"sticky tape",one part of macromolecule is anchored to the metal surface while the other can be elongated due to effective mean(molecular)field of dipolar type formed by free ends of other chains.The dynamic Monte-Carlo method for Langmuir's model is used for calculation of adhesion force taking into account the interaction energy of monomers with the metal surface.It is shown that conformation of polymer chain is defined by temperature conditions of its formation.The obtained results are confirmed by the data of production tests on polymer coatings in JSC"Severstal".
文摘We investigated the influence of particle shape and solubility on the caking behavior of trisodium phosphate by considering the adhesion free energy and crystal bridge theory. Caking of trisodium phosphate during the drying process under static conditions is a two-step process: adhesion followed by crystal bridge formation between particles. The adhesion free energy plays an important role in adhesion. Trisodium phosphate particles cannot adhere to each other and cake when the adhesion free energy is greater than a critical value, which varies with particle shape. Compared with granular particles, cylindrical particles have larger contact area between particles, which results in more crystal bridges forming and a higher caking ratio. Thus, the critical value is about 100 mJ/m^2 for cylindrical particles, but 60 mJ/m^2 for granular particles at 25 ℃. Concerning the solubility, when particles are similar shapes and soluble in the rinsing liquid, the caking ratio has a linear relationship with adhesion free energy. However, if the particles are insoluble in the rinsing liquid, caking can be completely prevented regardless of adhesion free energy because no crystal bridges form during the growth process. Hence, caking of trisodium phosphate particles could be inhibited by screening rinsing liquids, and optimizing the particle shape and size distribution.