A novel simple two-dimensional square-lattice model of amphiphile at oil-water interface is developed,in which oil and water act as solvent and occupy empty sites and amphiphile occupies chains of sites. In this mode...A novel simple two-dimensional square-lattice model of amphiphile at oil-water interface is developed,in which oil and water act as solvent and occupy empty sites and amphiphile occupies chains of sites. In this model, the oil-water interface is fixed, And amphiphile molecules will be enriched at the oil-water interface. The interfacial concentration of amphiphile calculated by Monte Carlo method shows that it is easier for the hydrophilic-hydrophobic balanced amphiphile to stay at the interface. And the adsorption of amphiphile increases with the increase of amphiphile concentration and the decrease with temperature.展开更多
Amphiphile-oil-water system is complicated. The real behavior of amphiphile in the interface is still undnown despite that this behavior is very important in determining the stability of emulsion system. In this paper...Amphiphile-oil-water system is complicated. The real behavior of amphiphile in the interface is still undnown despite that this behavior is very important in determining the stability of emulsion system. In this paper, the interface properties of amphiphile at oil-water interface were investigated by a square-lattice model Monte Carlo simulation method. The synergistic effect was found for hydrophobic and hydrophilic amphiphile mixture systems; and the synergistic effect disappears or was weakened as the amphiphile at the interface region became dilute with the increasing of temperature.展开更多
To study the effect of interface behaviour on the mechanical properties and damage evolution of PBX under combined tension-shear loading, the present work establishes the numerical model of a PBX three-phase hybrid sy...To study the effect of interface behaviour on the mechanical properties and damage evolution of PBX under combined tension-shear loading, the present work establishes the numerical model of a PBX three-phase hybrid system, which introduces a nonlinear plastic damage cohesion model to study the mechanical response and damage process. The parameters in the model were fitted and calibrated.Taking the crack growth rate as the feature, the damage state in each stage was determined, and the damage instability criterion was given. The effects of interfacial tensile strength and shear strength on the damage process of PBX were studied. On this basis, serrated and hemispherical structures interface of PBX has been developed, which affects the damage process and instability during the loading process.The results indicate that damage state response of PBX experiences the process of stable load bearing,unstable propagation, and complete failure. At the critical moment of instability, the overall equivalent effective strain of material reaches 3024 με and instability loading displacement reaches 0.39 mm. The increase of interfacial tensile strength and shear strength significantly inhibits the damage of PBX. The effect of interfacial shear strength on critical instability of PBX is approximately 1.7 times that of the interfacial tensile strength. Further, interface opening along the normal direction is the main damage form at the interface. Serrated and hemispherical rough interfaces can significantly inhibit propagation of cracks, and the load bearing capacity is improved by 22% and 9.7%, respectively. Appropriate improvement of the roughness of the interface structure can effectively improve the mechanical properties. It is significantly important to have a better understanding of deformation, damage and failure mechanisms of PBX and to improve our predictive ability.展开更多
In the context of the Cigeo project,the French National Radioactive Waste Management Agency(Andra)is studying the behaviour of a deep geological facility for radioactive waste deposit in the CallovoOxfordian(COx)clays...In the context of the Cigeo project,the French National Radioactive Waste Management Agency(Andra)is studying the behaviour of a deep geological facility for radioactive waste deposit in the CallovoOxfordian(COx)claystone.The assessment of durability of this project requires the prediction of irreversible strain over a large time scale.The mechanical interaction of the host rock and the concrete support of tunnels must be investigated to ensure the long-term sustainability of the structure.The instantaneous and time-dependent behaviour of the claystone-concrete interface is experimentally investigated with direct shear tests and long-duration shear tests of a few months.The mechanical and structural state of the claystone which is affected after interaction with concrete reflects to the response of the claystone-concrete interface,and thus different types of COx claystone-concrete interfaces are tested.The delayed deformation of the interface is found to be linked to the level of the normal loading and the loading history while a different response of the interface was observed from the short-and long-duration tests,indicating a possible progressive modification of interface under long-duration loadings.展开更多
By means of electron probe(EPMA),scanning electron microscope(SEM),and optical microscope (QM),the diffusion behaviour on the Fe-Cu interface of copper brazed double-wall steel tubes and the microstructure of the diff...By means of electron probe(EPMA),scanning electron microscope(SEM),and optical microscope (QM),the diffusion behaviour on the Fe-Cu interface of copper brazed double-wall steel tubes and the microstructure of the diffusion layer have been investigated.There are three kinds of metallurgical bonds between copper plating layer and steel substrate: (1)the Cu diffusing into steel substrate along grain boundary of ferrite;(2)the Cu diffusion into grain bulk of ferrite: (3)the Fe diffusing into Cu layer.The copper brazed double-wall steel tubes are formed by the combination of the diffusions mentioned above and this is the reason for excellent mechanical and technological properties of the copper brazed double-wall steel tubes.展开更多
By using newly developed CuNi5~25Ti16~28 B rapldly solidifled brazing filler the joining of Si3 N4/1.25Cr-0.5Mo steel has been carried out with interlayer method. If employing the interlayer structure of steel (0.2 mm...By using newly developed CuNi5~25Ti16~28 B rapldly solidifled brazing filler the joining of Si3 N4/1.25Cr-0.5Mo steel has been carried out with interlayer method. If employing the interlayer structure of steel (0.2 mm)/W (2.0 mm)/Ni(0.2 mm), the joint strength can be increased greatly compared with employing that of Ni/W/Ni, and the three point bend strength of the Joint shows the value of 261 MPa. The metallurgical behaviour at the interface between Si3N4 and the interlayer has been studied. It is found that Fe participated in the interfacial reactions between Si3N4 and the brazing filler at the Si3N4/steel (0.2 mm) interface and the compound Fe5Si3 was produced. However, since the reactions of Fe with the active Ti are weaker than those of Ni with Ti, the normal inter facial reactions were still assured at the interface of Si3N4/steel (0.2 mm) instead of Si3N4/Ni (0.2 mm), resulting in the improvement of the joint strength. The mechanism of the formation of Fe5Si3 is also discussed. Finally, some ideas to further ameliorate and simplify the interlayer structure are put forward.展开更多
Based on the circuit principle of 1186 Electro Chemical Interface preduced by Solartron Electronic Group Ltd., a precise electro chemical interface (ECI) unit, which can provide the interfacing requirements for the co...Based on the circuit principle of 1186 Electro Chemical Interface preduced by Solartron Electronic Group Ltd., a precise electro chemical interface (ECI) unit, which can provide the interfacing requirements for the control and measurement of characteristics of electro chemical cell, was developed by means of some essential improvements. Not only can it be used to control and measure the steady and non-steady state characteristics, but also it can be directly connected with Solartron 1170 series or 1250 Frequency Response Analysers (FRA) to measure the AC impedance. Besides,the EC1 can also be connected with two- or three-electrode electro chemical cell systems to test convenlently and correctly their DC and AC characteristics, and used as a four-electrode potentlostat combined with four-electrode electro chernical cell system which contains two reference electrodes (RES) for researches on the electro chemical characteristics of oil-water interface, etc.展开更多
In this study, the authors reviewed and compared the existing researches on debonding performance of FRP-Concrete Interface under direct shear firstly. Following that, two determinants of the debonding ultimate bearin...In this study, the authors reviewed and compared the existing researches on debonding performance of FRP-Concrete Interface under direct shear firstly. Following that, two determinants of the debonding ultimate bearing capacity of FRP-Concrete Interface under pure shear are introduced into this study, namely fracture-resisting force at the undamaged area and friction stress transferred along the already debonded surface. The authors deduced the formulae on fracture energy for FRP-Concrete Interface and obtained the values for fracture energy and friction stress at FRP-Concrete Interface based on the experimental results of eight specimens of FRP-Concrete Interface. On the basis of theoretical frame mentioned above, the authors concluded that the friction-resisting stress transferred along the deteriorated bi-material interface is independent of length of FRP bonded onto concrete substrates and concrete strength, but it relies on the tension rigidity （i.e., the layers of the bonding FRP, it is found that the friction stress declines substantially while the layers of FRP increases bonded to concrete substrate）. On the contrary, cohesive fracture energy is dependent on length of FRP bonded to concrete substrate and the tension stiffness of bi-material interface. In addition, the percentage of the fracture-resisting force in the ultimate debonding load at the interface decreases with the bonding length of FRP increasing, but increases with the increase of the layers of the FRP.展开更多
Electrocatalytic conversion presents a promising alternative to conventional industrial catalysis.While aqueous-phase electrocatalysis has achieved notable advancements,oil-water immiscible systems remain challenging ...Electrocatalytic conversion presents a promising alternative to conventional industrial catalysis.While aqueous-phase electrocatalysis has achieved notable advancements,oil-water immiscible systems remain challenging due to restricted reaction flux at multiphase interfaces.To address the limitation,we engineered a biphasic reaction system featuring a tailored oil-water catalytic interface in cyclohexene oxidation reaction(COR).The system employed a catalyst-loaded porous electrode as an active phase domain,enabling spatial separation of cyclohexene(organic phase)and electrolyte(aqueous phase).The tailored oil-water interface enhanced the interfacial mass transfer of substrate-catalysts and facilitated the spontaneous migration of 2-cyclohexen-1-ol into the aqueous phase,thereby streamlining product separation.Notably,polyaniline(PANI)modification on Co_(3)O_(4)enhanced surface lipophilicity,promoting cyclohexene adsorption and accelerating the COR catalytic kinetics(Co^(3+)-O+cyclohexene-H+e-→Co^(2+)-OH+2-cyclohexen-1-ol).The synergistic effects of optimized interfacial engineering and catalyst functionalization achieved exceptional performance:a current density of 45 mA·cm^(-2)at 1.6 V vs.reversible hydrogen electrode(V_(RHE)),coupled with 96.2%selectivity and 82.9%Faradaic efficiency.This work establishes an innovative paradigm for electrocatalytic conversions in oil-water immiscible systems through rational interface design and catalyst surface modulation.展开更多
Layered epoxy/paper composites that exhibit excellent insulating characteristics under elevated electrification and temperature conditions are essential components for power system insulation.Yet,inevitable charge acc...Layered epoxy/paper composites that exhibit excellent insulating characteristics under elevated electrification and temperature conditions are essential components for power system insulation.Yet,inevitable charge accumulation occurs at hetero interfaces between layers due to interfacial polarisation and interface barrier effect,bringing about local electric field distortion and potential risk of partial discharge.A fundamental challenge is either to obtain accurate interface charge behaviours of in-service multi-layer insulating composites,or to construct verified simulating models for replacing experiments.Herein,a modified bipolar charge transport model to simulate interface charge behaviours in layered composites is proposed.With model parameters directly originated from equivalent experiments(e.g.conduction current measurement,thermally stimulated depolarisation current testing,and ultraviolet-visible spectroscopy)of epoxy/paper composites,the simulated temperature-dependent interface charge characteristics match well with pulsed electro-acoustic results.Furthermore,electrical thresholds can also be accurately calculated using such models(maximum deviation of 8.44%from experimental results),providing references for optimised insulation structural design.展开更多
基金Supported by the National Natural Science Foundation of China (No. 29736170)and the Natural Science Foundation of Zhejiang Province(No. RC01051).
文摘A novel simple two-dimensional square-lattice model of amphiphile at oil-water interface is developed,in which oil and water act as solvent and occupy empty sites and amphiphile occupies chains of sites. In this model, the oil-water interface is fixed, And amphiphile molecules will be enriched at the oil-water interface. The interfacial concentration of amphiphile calculated by Monte Carlo method shows that it is easier for the hydrophilic-hydrophobic balanced amphiphile to stay at the interface. And the adsorption of amphiphile increases with the increase of amphiphile concentration and the decrease with temperature.
基金Supported by the National Natural Science Foundation of China (No. 29736170) the Natural Science Foundation of Zhejiang Province (No. RC01051).
文摘Amphiphile-oil-water system is complicated. The real behavior of amphiphile in the interface is still undnown despite that this behavior is very important in determining the stability of emulsion system. In this paper, the interface properties of amphiphile at oil-water interface were investigated by a square-lattice model Monte Carlo simulation method. The synergistic effect was found for hydrophobic and hydrophilic amphiphile mixture systems; and the synergistic effect disappears or was weakened as the amphiphile at the interface region became dilute with the increasing of temperature.
基金the China National Nature Science Foundation (Grant No. 11872119)China Postdoctoral Science Foundation (Grant Nos. BX20200046, 2020M680394)Pre-research Project of Armament (Grant No. 6142A03202002) for supporting this project
文摘To study the effect of interface behaviour on the mechanical properties and damage evolution of PBX under combined tension-shear loading, the present work establishes the numerical model of a PBX three-phase hybrid system, which introduces a nonlinear plastic damage cohesion model to study the mechanical response and damage process. The parameters in the model were fitted and calibrated.Taking the crack growth rate as the feature, the damage state in each stage was determined, and the damage instability criterion was given. The effects of interfacial tensile strength and shear strength on the damage process of PBX were studied. On this basis, serrated and hemispherical structures interface of PBX has been developed, which affects the damage process and instability during the loading process.The results indicate that damage state response of PBX experiences the process of stable load bearing,unstable propagation, and complete failure. At the critical moment of instability, the overall equivalent effective strain of material reaches 3024 με and instability loading displacement reaches 0.39 mm. The increase of interfacial tensile strength and shear strength significantly inhibits the damage of PBX. The effect of interfacial shear strength on critical instability of PBX is approximately 1.7 times that of the interfacial tensile strength. Further, interface opening along the normal direction is the main damage form at the interface. Serrated and hemispherical rough interfaces can significantly inhibit propagation of cracks, and the load bearing capacity is improved by 22% and 9.7%, respectively. Appropriate improvement of the roughness of the interface structure can effectively improve the mechanical properties. It is significantly important to have a better understanding of deformation, damage and failure mechanisms of PBX and to improve our predictive ability.
文摘In the context of the Cigeo project,the French National Radioactive Waste Management Agency(Andra)is studying the behaviour of a deep geological facility for radioactive waste deposit in the CallovoOxfordian(COx)claystone.The assessment of durability of this project requires the prediction of irreversible strain over a large time scale.The mechanical interaction of the host rock and the concrete support of tunnels must be investigated to ensure the long-term sustainability of the structure.The instantaneous and time-dependent behaviour of the claystone-concrete interface is experimentally investigated with direct shear tests and long-duration shear tests of a few months.The mechanical and structural state of the claystone which is affected after interaction with concrete reflects to the response of the claystone-concrete interface,and thus different types of COx claystone-concrete interfaces are tested.The delayed deformation of the interface is found to be linked to the level of the normal loading and the loading history while a different response of the interface was observed from the short-and long-duration tests,indicating a possible progressive modification of interface under long-duration loadings.
文摘By means of electron probe(EPMA),scanning electron microscope(SEM),and optical microscope (QM),the diffusion behaviour on the Fe-Cu interface of copper brazed double-wall steel tubes and the microstructure of the diffusion layer have been investigated.There are three kinds of metallurgical bonds between copper plating layer and steel substrate: (1)the Cu diffusing into steel substrate along grain boundary of ferrite;(2)the Cu diffusion into grain bulk of ferrite: (3)the Fe diffusing into Cu layer.The copper brazed double-wall steel tubes are formed by the combination of the diffusions mentioned above and this is the reason for excellent mechanical and technological properties of the copper brazed double-wall steel tubes.
文摘By using newly developed CuNi5~25Ti16~28 B rapldly solidifled brazing filler the joining of Si3 N4/1.25Cr-0.5Mo steel has been carried out with interlayer method. If employing the interlayer structure of steel (0.2 mm)/W (2.0 mm)/Ni(0.2 mm), the joint strength can be increased greatly compared with employing that of Ni/W/Ni, and the three point bend strength of the Joint shows the value of 261 MPa. The metallurgical behaviour at the interface between Si3N4 and the interlayer has been studied. It is found that Fe participated in the interfacial reactions between Si3N4 and the brazing filler at the Si3N4/steel (0.2 mm) interface and the compound Fe5Si3 was produced. However, since the reactions of Fe with the active Ti are weaker than those of Ni with Ti, the normal inter facial reactions were still assured at the interface of Si3N4/steel (0.2 mm) instead of Si3N4/Ni (0.2 mm), resulting in the improvement of the joint strength. The mechanism of the formation of Fe5Si3 is also discussed. Finally, some ideas to further ameliorate and simplify the interlayer structure are put forward.
文摘Based on the circuit principle of 1186 Electro Chemical Interface preduced by Solartron Electronic Group Ltd., a precise electro chemical interface (ECI) unit, which can provide the interfacing requirements for the control and measurement of characteristics of electro chemical cell, was developed by means of some essential improvements. Not only can it be used to control and measure the steady and non-steady state characteristics, but also it can be directly connected with Solartron 1170 series or 1250 Frequency Response Analysers (FRA) to measure the AC impedance. Besides,the EC1 can also be connected with two- or three-electrode electro chemical cell systems to test convenlently and correctly their DC and AC characteristics, and used as a four-electrode potentlostat combined with four-electrode electro chernical cell system which contains two reference electrodes (RES) for researches on the electro chemical characteristics of oil-water interface, etc.
文摘In this study, the authors reviewed and compared the existing researches on debonding performance of FRP-Concrete Interface under direct shear firstly. Following that, two determinants of the debonding ultimate bearing capacity of FRP-Concrete Interface under pure shear are introduced into this study, namely fracture-resisting force at the undamaged area and friction stress transferred along the already debonded surface. The authors deduced the formulae on fracture energy for FRP-Concrete Interface and obtained the values for fracture energy and friction stress at FRP-Concrete Interface based on the experimental results of eight specimens of FRP-Concrete Interface. On the basis of theoretical frame mentioned above, the authors concluded that the friction-resisting stress transferred along the deteriorated bi-material interface is independent of length of FRP bonded onto concrete substrates and concrete strength, but it relies on the tension rigidity （i.e., the layers of the bonding FRP, it is found that the friction stress declines substantially while the layers of FRP increases bonded to concrete substrate）. On the contrary, cohesive fracture energy is dependent on length of FRP bonded to concrete substrate and the tension stiffness of bi-material interface. In addition, the percentage of the fracture-resisting force in the ultimate debonding load at the interface decreases with the bonding length of FRP increasing, but increases with the increase of the layers of the FRP.
基金supported by the National Natural Science Foundation of China(No.22278380)China Postdoctoral Science Foundation(Nos.2024M762994 and GZC20232392)supported by the project of Yunnan Key Laboratory of Electromagnetic Materials and Devices,Yunnan University(No.ZZ2024009).
文摘Electrocatalytic conversion presents a promising alternative to conventional industrial catalysis.While aqueous-phase electrocatalysis has achieved notable advancements,oil-water immiscible systems remain challenging due to restricted reaction flux at multiphase interfaces.To address the limitation,we engineered a biphasic reaction system featuring a tailored oil-water catalytic interface in cyclohexene oxidation reaction(COR).The system employed a catalyst-loaded porous electrode as an active phase domain,enabling spatial separation of cyclohexene(organic phase)and electrolyte(aqueous phase).The tailored oil-water interface enhanced the interfacial mass transfer of substrate-catalysts and facilitated the spontaneous migration of 2-cyclohexen-1-ol into the aqueous phase,thereby streamlining product separation.Notably,polyaniline(PANI)modification on Co_(3)O_(4)enhanced surface lipophilicity,promoting cyclohexene adsorption and accelerating the COR catalytic kinetics(Co^(3+)-O+cyclohexene-H+e-→Co^(2+)-OH+2-cyclohexen-1-ol).The synergistic effects of optimized interfacial engineering and catalyst functionalization achieved exceptional performance:a current density of 45 mA·cm^(-2)at 1.6 V vs.reversible hydrogen electrode(V_(RHE)),coupled with 96.2%selectivity and 82.9%Faradaic efficiency.This work establishes an innovative paradigm for electrocatalytic conversions in oil-water immiscible systems through rational interface design and catalyst surface modulation.
基金Science and Technology Project of State Grid Corporation of China,Grant/Award Number:SGLNDK00KJJS1900250。
文摘Layered epoxy/paper composites that exhibit excellent insulating characteristics under elevated electrification and temperature conditions are essential components for power system insulation.Yet,inevitable charge accumulation occurs at hetero interfaces between layers due to interfacial polarisation and interface barrier effect,bringing about local electric field distortion and potential risk of partial discharge.A fundamental challenge is either to obtain accurate interface charge behaviours of in-service multi-layer insulating composites,or to construct verified simulating models for replacing experiments.Herein,a modified bipolar charge transport model to simulate interface charge behaviours in layered composites is proposed.With model parameters directly originated from equivalent experiments(e.g.conduction current measurement,thermally stimulated depolarisation current testing,and ultraviolet-visible spectroscopy)of epoxy/paper composites,the simulated temperature-dependent interface charge characteristics match well with pulsed electro-acoustic results.Furthermore,electrical thresholds can also be accurately calculated using such models(maximum deviation of 8.44%from experimental results),providing references for optimised insulation structural design.
