Abundant interfacial defects remain a significant challenge that hampers both the efficiency and stability of perovskite solar cells(PSCs).Herein,an alcohol-dispersed conducting polymer complex,denoted as PEDOT:F(Poly...Abundant interfacial defects remain a significant challenge that hampers both the efficiency and stability of perovskite solar cells(PSCs).Herein,an alcohol-dispersed conducting polymer complex,denoted as PEDOT:F(Poly(3,4-ethylene dioxythiophene):Perfluorinated sulfonic acid ionomers),is introduced into the interface between perovskite and hole transporting layer in regular-structured PSCs.PEDOT:F serves as a multi-functional interface layer(filling grain boundaries and covering perovskite's grain-surface)to achieve a robust interaction with organic groups within perovskites,which could induce a structural transformation of PEDOT to increase its conductivity for the efficient hole-transport.Furthermore,the strong interaction between PEDOT and perovskites could promote an effective coupling of undercoordinated Pb~(2+)ions with the lone electron pairs near O&S atoms in PEDOT molecules,thereby enhancing defect passivation.Additionally,PEDOT:F with inherent hydrophobic properties prevents effectively moisture invasion into perovskites for the improved long-term stability of the PSCs.Consequently,the PEDOT:F-based PSCs achieved a champion efficiency of 24.81%,and maintained ca.92%of their initial efficiency after 7680 h of storage in a dry air environment,accompanied by the enhanced photothermal stability.展开更多
For the further improvement of the power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs),the buried interface between the perovskite and the electron transport layer is crucial.However,it is ch...For the further improvement of the power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs),the buried interface between the perovskite and the electron transport layer is crucial.However,it is challenging to effectively optimize this interface as it is buried beneath the perovskite film.Herein,we have designed and synthesized a series of multifunctional organic-inorganic(OI)complexes as buried interfacial material to promote electron extraction,as well as the crystal growth of the perovskite.The OI complex with BF4−group not only eliminates oxygen vacancies on the SnO_(2) surface but also balances energy level alignment between SnO_(2) and perovskite,providing a favorable environment for charge carrier extraction.Moreover,OI complex with amine(−NH_(2))functional group can regulate the crystallization of the perovskite film via interaction with PbI2,resulting in highly crystallized perovskite film with large grains and low defect density.Consequently,with rational molecular design,the PSCs with optimal OI complex buried interface layer which contains both BF4−and−NH_(2) functional groups yield a champion device efficiency of 23.69%.More importantly,the resulting unencapsulated device performs excellent ambient stability,maintaining over 90%of its initial efficiency after 2000 h storage,and excellent light stability of 91.5%remaining PCE in the maximum power point tracking measurement(under continuous 100 mW cm−2 light illumination in N2 atmosphere)after 500 h.展开更多
Viscoelastic flows play an important role in numerous engineering fields,and the multiscale algorithms for simulating viscoelastic flows have received significant attention in order to deepen our understanding of the ...Viscoelastic flows play an important role in numerous engineering fields,and the multiscale algorithms for simulating viscoelastic flows have received significant attention in order to deepen our understanding of the nonlinear dynamic behaviors of viscoelastic fluids.However,traditional grid-based multiscale methods are confined to simple viscoelastic flows with short relaxation time,and there is a lack of uniform multiscale scheme available for coupling different solvers in the simulations of viscoelastic fluids.In this paper,a universal multiscale method coupling an improved smoothed particle hydrodynamics(SPH)and multiscale universal interface(MUI)library is presented for viscoelastic flows.The proposed multiscale method builds on an improved SPH method and leverages the MUI library to facilitate the exchange of information among different solvers in the overlapping domain.We test the capability and flexibility of the presented multiscale method to deal with complex viscoelastic flows by solving different multiscale problems of viscoelastic flows.In the first example,the simulation of a viscoelastic Poiseuille flow is carried out by two coupled improved SPH methods with different spatial resolutions.The effects of exchanging different physical quantities on the numerical results in both the upper and lower domains are also investigated as well as the absolute errors in the overlapping domain.In the second example,the complex Wannier flow with different Weissenberg numbers is further simulated by two improved SPH methods and coupling the improved SPH method and the dissipative particle dynamics(DPD)method.The numerical results show that the physical quantities for viscoelastic flows obtained by the presented multiscale method are in consistence with those obtained by a single solver in the overlapping domain.Moreover,transferring different physical quantities has an important effect on the numerical results.展开更多
The field of environmental sciences is abundant with various interfaces and is the right place for the application of new fundamental approaches leading towards a better understanding of environmental phenomena. Follo...The field of environmental sciences is abundant with various interfaces and is the right place for the application of new fundamental approaches leading towards a better understanding of environmental phenomena. Following the definition of environmental interface by Mihailovic and Bala? [1], such interface can be, for example, placed between: human or animal bodies and surrounding air, aquatic species and water and air around them, and natural or artificially built surfaces (vegetation, ice, snow, barren soil, water, urban communities) and the atmosphere, cells and surrounding environment, etc. Complex environmental interface systems are (i) open and hierarchically organised (ii) interactions between their constituent parts are nonlinear, and (iii) their interaction with the surrounding environment is noisy. These systems are therefore very sensitive to initial conditions, deterministic external perturbations and random fluctuations always present in nature. The study of noisy non-equilibrium processes is fundamental for modelling the dynamics of environmental interface regarded as biophysical complex system and for understanding the mechanisms of spatio-temporal pattern formation in contemporary environmental sciences. In this paper we will investigate an aspect of dynamics of energy flow based on the energy balance equation. The energy exchange between interacting environmen- tal interfaces regarded as biophysical complex systems can be represented by coupled maps. Therefore, we will numerically investigate coupled maps representing that exchange. In ana- lysis of behaviour of these maps we applied Lyapunov exponent and cross sample entropy.展开更多
With increasing usage of a web services today, user required to consecrate reasoning energy to learning the complexities of the interface as opposed to the content. Interface complexity measures the degree of complexi...With increasing usage of a web services today, user required to consecrate reasoning energy to learning the complexities of the interface as opposed to the content. Interface complexity measures the degree of complexity encountered between the user and digital medium like website. This paper presents a New Interface Complexity (NIC) Metric, which partially based on existing schema metrics to weigh human insight of recent service interface;taking into account elements and attributes of XML documents implemented in?World Wide Web Consortium (W3C) XML Schema (WXS) to reduce the structure affecting the effort for comprehending schema documents. The NIC metric is able to draw conclusions about the perceived qualities: interoperability, extensibility and flexibility. It was discovered that there are significant correlations between NIC metric and existing measures. Automating, this practice would be beneficial to developers and designers, as it would help to provide useful feedback in software project design to check the quality of documents for easy maintenance and properly used of XML data for distributed applications.展开更多
In this paper, the eigen function expansions of displacements and stresses of bi-metal laminates with interface cracks are obtained. Furthermore, the stress intensity factors are determined by the variational method t...In this paper, the eigen function expansions of displacements and stresses of bi-metal laminates with interface cracks are obtained. Furthermore, the stress intensity factors are determined by the variational method to satisfy the boundary conditions and there are only line integrals in the variational equations due to the previous satisfaction of all basic equations. The computations show that this method of solution has the advantages of rapid convergency and time-saving. The results obtained by this method for homogeneous material agree with the known ones very well.展开更多
We have defined the environmental interface through the exchange processes between media forming this interface. Considering the environmental interface as a complex system we elaborated the advanced mathematical tool...We have defined the environmental interface through the exchange processes between media forming this interface. Considering the environmental interface as a complex system we elaborated the advanced mathematical tools for its modelling. We have suggested two coupled maps serving the exchange processes on the environmental interfaces spatially ranged from cellular to planetary level, i.e. 1) the map with diffusive coupling for energy exchange simulation and 2) the map with affinity, which is suitable for matter exchange processes at the cellular level. We have performed the dynamical analysis of the coupled maps using the Lyapunov exponent, cross sample as well as the permutation entropy in dependence on different map parameters. Finally, we discussed the map with affinity, which shows some features making it a promising toll in simulation of exchange processes on the environmental interface at the cellular level.展开更多
The generalized two_dimensional problem of a dielectric rigid line inclusion, at the interface between two dissimilar piezoelectric media subjected to piecewise uniform loads at infinity, is studied by means of the St...The generalized two_dimensional problem of a dielectric rigid line inclusion, at the interface between two dissimilar piezoelectric media subjected to piecewise uniform loads at infinity, is studied by means of the Stroh theory. The problem was reduced to a Hilbert problem, and then closed_form expressions were obtained, respectively, for the complex potentials in piezoelectric media, the electric field inside the inclusion and the tip fields near the inclusion. It is shown that in the media, all field variables near the inclusion_tip show square root singularity and oscillatory singularity, the intensity of which is dependent on the material constants and the strains at infinity. In addition, it is found that the electric field inside the inclusion is singular and oscillatory too, when approaching the inclusion_tips from inside the inclusion.展开更多
In modern chemical engineering processes, solid interface involvement is the most important component of process intensification techniques, such as nanoporous membrane separation and heterogeneous catalysis. The fund...In modern chemical engineering processes, solid interface involvement is the most important component of process intensification techniques, such as nanoporous membrane separation and heterogeneous catalysis. The fundamental mechanism underlying interfacial transport remains incompletely understood given the complexity of heterogeneous interfacial molecular interactions and the high nonideality of the fluid involved. Thus, understanding the effects of interface-induced fluid microstructures on flow resistance is the first step in further understanding interfacial transport. Molecular simulation has become an indispensable method for the investigation of fluid microstructure and flow resistance. Here, we reviewed the recent research progress of our group and the latest relevant works to elucidate the contribution of interface-induced fluid microstructures to flow resistance.We specifically focused on water, ionic aqueous solutions, and alcohol–water mixtures given the ubiquity of these fluid systems in modern chemical engineering processes. We discussed the effects of the interfaceinduced hydrogen bond networks of water molecules, the ionic hydration of ionic aqueous solutions, and the spatial distributions of alcohol and alcohol–water mixtures on flow resistance on the basis of the distinctive characteristics of different fluid systems.展开更多
In well stimulation treatments using hydrochloric acid,undesirable water-in-oil emulsion and acid sludge may produce and then cause operational problems in oil field development.The processes intensify in the presence...In well stimulation treatments using hydrochloric acid,undesirable water-in-oil emulsion and acid sludge may produce and then cause operational problems in oil field development.The processes intensify in the presence of Fe(Ⅲ),which are from the corroded surfaces of field equipment and/or iron-bearing minerals of the oil reservoir.In order to understand the reasons of the stability of acid emulsions,acid emulsions were prepared by mixing crude oil emulsion with 15% hydrochloric acid solutions with and without Fe(Ⅲ) and then separated into free and upper(water free) and intermediate(with water) layers.It is assumed that the oil phase of the free and upper layers contains the compounds which do not participate in the formation of acid emulsions,and the oil phase of the intermediate layers contains components involved in the formation of oil/acid interface.The composition of the oil phase of each layer of the emulsions was studied.It is found that the asphaltenes with a high content of sulfur,oxygen and metals as well the flocculated material of protonated non-polar oil components are concentrated at the oil/acid interface.In addition to the above,in the presence of Fe(Ⅲ) the Fe(Ⅲ)-based complexes with polar groups of asphaltenes are formed at the acid/oil interface,contributing to the formation of armor films which enhance the emulsion stability.展开更多
The correlation between surface complexation at the SiO_(2)H_(2)O interface and quartz notation behavior was studied.Computer assisted calculations,using the programs SOLGASWATER,were adapted in order to con-struct di...The correlation between surface complexation at the SiO_(2)H_(2)O interface and quartz notation behavior was studied.Computer assisted calculations,using the programs SOLGASWATER,were adapted in order to con-struct distribution diagrams of surface speciation in the SiO_(2)-metal ion-H^(+) system in aqueous solutions.Equilib-rium constants for both surface and solution reactions were introduced in the composition matrix.Surface complexation,surface charge as well as notation results were compared and a good agreement was obtained.Furthermore,flotation mechanisms of quartz activation by common metal ions like Ca^(2+),Mg^(2+),Fe^(2+) are quantitatively discussed based on the surface reaction equilibrium constants.展开更多
The generalized two-dimensional problem of a dielectric rigid line inclusion, at the interface between two dissimilar piezoelectric media subjected to piecewise uniform loads at infinity, is studied by means of the St...The generalized two-dimensional problem of a dielectric rigid line inclusion, at the interface between two dissimilar piezoelectric media subjected to piecewise uniform loads at infinity, is studied by means of the Stroh theory. The problem was reduced to a Hilbert problem, and then closed-form expressions were obtained, respectively, far the complex potentials in piezoelectric media, the electric field inside the inclusion and the tip fields near the inclusion. it is shown that in the media, all field variables near the inclusion-tip show square root singularity and oscillatory singularity, the intensity of which is dependent on the material constants and the strains at infinity. In addition, it is found that the electric field inside the inclusion is singular and oscillatory too, when approaching the inclusion-tips from inside the inclusion.展开更多
By the theory of complex functions, the dynamic propagation problem on Dugdale model of mode Ⅲ interface crack for nonlinear characters of materials was studied. The general expressions of analytical solutions are ob...By the theory of complex functions, the dynamic propagation problem on Dugdale model of mode Ⅲ interface crack for nonlinear characters of materials was studied. The general expressions of analytical solutions are obtained by the methods of self-similar functions. The problems dealt with can be easily transformed into Riemann-Hilbert problems and their closed solutions are attained rather simply by this approach. After those solutions were utilized by superposition theorem, the solutions of arbitrarily complex problems could be obtained.展开更多
By the application of the theory of complex functions, asymmetrical dynamic propagation problems on mode Ⅲ interface crack are studied. The universal representations of analytical solutions are obtained by the approa...By the application of the theory of complex functions, asymmetrical dynamic propagation problems on mode Ⅲ interface crack are studied. The universal representations of analytical solutions are obtained by the approaches of self-similar function. The problems researched can be facilely transformed into Riemann-Hilbert problems and analytical solution to an asymmetrical propagation crack under the condition of point loads and unit-step loads, respectively, is acquired. After those solutions were used by superposition theorem, the solutions of arbitrarily complex problems could be attained.展开更多
Interface imperfection can significantly affect the mechanical properties and failure mechanisms as well as the strength and toughness of nanocomposites. The elastic behavior of a screw dislocation in nanoscale coatin...Interface imperfection can significantly affect the mechanical properties and failure mechanisms as well as the strength and toughness of nanocomposites. The elastic behavior of a screw dislocation in nanoscale coating with imperfect interface is studied in the three-phase composite cylinder model. The interface between inner nanoin- homogeneity and intermediate coating is assumed as perfectly bonded. The bonding between intermediate coating and outer matrix is considered to be imperfect with the assumption that interface imperfection is uniform, and a linear spring model is adopted to describe the weakness of imperfect interface. The explicit expression for image force acting on dislocation is obtained by means of a complex variable method. The analytic results indicate that inner interface effect and outer interface imperfection, simultaneously taken into account, would influence greatly image force, equilibrium position and stability of dislocation, and various critical parameters that would change dislocation stability. The weaker interface is a very strong trap for glide dislocation and, thus, a more effective barrier for slip transmission.展开更多
The morphology and interface of perovskite film are very important for the performance of perovskite solar cells(PSCs).The quality of perovskite film,fabricated via two-step spin-coating process,is significantly influ...The morphology and interface of perovskite film are very important for the performance of perovskite solar cells(PSCs).The quality of perovskite film,fabricated via two-step spin-coating process,is significantly influenced by the morphology and crystallinity of PbI2 film.With the addition of additive dimethyl sulfoxide(DMSO)into the PbI2 precursor,the roughness and trap-state density of perovskite film have been significantly reduced,leading to the excellent contact between perovskite layer and subsequent deposited carrier transport layer.Accordingly,the planar heterojunction PSCs with an architecture of ITO/SnO2/perovskite/PTAA/Ag show an efficiency up to 19.02%.Furthermore,PSCs exhibit promising stability in air with a humidity of ~45%,and retain 80% of initial efficiency after being exposed to air for 400 h without any encapsulation.展开更多
Protein-protein complexes play an important role in the physiology and the pathology of cellular functions, and therefore are attractive therapeutic targets. A small subset of residues known as “hot spots”, accounts...Protein-protein complexes play an important role in the physiology and the pathology of cellular functions, and therefore are attractive therapeutic targets. A small subset of residues known as “hot spots”, accounts for most of the protein-protein binding free energy. Computational methods play a critical role in identifying the hotspots on the proteinprotein interface. In this paper, we use a computational alanine scanning method with all-atom force fields for predicting hotspots for 313 mutations in 16 protein complexes of known structures. We studied the effect of force fields, solvation models, and conformational sampling on the hotspot predictions. We compared the calculated change in the protein-protein interaction energies upon mutation of the residues in and near the protein-protein interface, to the experimental change in free energies. The AMBER force field (FF) predicted 86% of the hotspots among the three commonly used FF for proteins, namely, AMBER FF, Charmm27 FF, and OPLS-2005 FF. However, AMBER FF also showed a high rate of false positives, while the Charmm27 FF yielded 74% correct predictions of the hotspot residues with low false positives. Van der Waals and hydrogen bonding energy show the largest energy contribution with a high rate of prediction accuracy, while the desolvation energy was found to contribute little to improve the hot spot prediction. Using a conformational ensemble including limited backbone movement instead of one static structure leads to better predicttion of hotpsots.展开更多
基金supported by the Science Foundation(K201827)the Open Foundation of Hubei Key Laboratory of Optical Information and Pattern Recognition(202103,202206)the Graduate Education Innovation Fund of Wuhan Institute of Technology(CX2023279,CX2023277,CX2023272)。
文摘Abundant interfacial defects remain a significant challenge that hampers both the efficiency and stability of perovskite solar cells(PSCs).Herein,an alcohol-dispersed conducting polymer complex,denoted as PEDOT:F(Poly(3,4-ethylene dioxythiophene):Perfluorinated sulfonic acid ionomers),is introduced into the interface between perovskite and hole transporting layer in regular-structured PSCs.PEDOT:F serves as a multi-functional interface layer(filling grain boundaries and covering perovskite's grain-surface)to achieve a robust interaction with organic groups within perovskites,which could induce a structural transformation of PEDOT to increase its conductivity for the efficient hole-transport.Furthermore,the strong interaction between PEDOT and perovskites could promote an effective coupling of undercoordinated Pb~(2+)ions with the lone electron pairs near O&S atoms in PEDOT molecules,thereby enhancing defect passivation.Additionally,PEDOT:F with inherent hydrophobic properties prevents effectively moisture invasion into perovskites for the improved long-term stability of the PSCs.Consequently,the PEDOT:F-based PSCs achieved a champion efficiency of 24.81%,and maintained ca.92%of their initial efficiency after 7680 h of storage in a dry air environment,accompanied by the enhanced photothermal stability.
基金The authors acknowledge the financial support from the Natural Science Foundation of China(Nos.21931002 and 22101123)the National Key Research and Development Program of China(2018YFB0704100)+4 种基金the Shenzhen Science and Technology Innovation Committee(no.JCYJ20200109140812302)the Leading talents of Guangdong province program(2016LJ06N507)the Guangdong Provincial Key Laboratory of Energy Materials for Electric Power(no.2018B030322001)the Guangdong Provincial Key Laboratory of Catalysis(no.2020B121201002)Outstanding Talents Training Fund in Shenzhen.
文摘For the further improvement of the power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs),the buried interface between the perovskite and the electron transport layer is crucial.However,it is challenging to effectively optimize this interface as it is buried beneath the perovskite film.Herein,we have designed and synthesized a series of multifunctional organic-inorganic(OI)complexes as buried interfacial material to promote electron extraction,as well as the crystal growth of the perovskite.The OI complex with BF4−group not only eliminates oxygen vacancies on the SnO_(2) surface but also balances energy level alignment between SnO_(2) and perovskite,providing a favorable environment for charge carrier extraction.Moreover,OI complex with amine(−NH_(2))functional group can regulate the crystallization of the perovskite film via interaction with PbI2,resulting in highly crystallized perovskite film with large grains and low defect density.Consequently,with rational molecular design,the PSCs with optimal OI complex buried interface layer which contains both BF4−and−NH_(2) functional groups yield a champion device efficiency of 23.69%.More importantly,the resulting unencapsulated device performs excellent ambient stability,maintaining over 90%of its initial efficiency after 2000 h storage,and excellent light stability of 91.5%remaining PCE in the maximum power point tracking measurement(under continuous 100 mW cm−2 light illumination in N2 atmosphere)after 500 h.
基金Project supported by the National Natural Science Foundation of China(No.52109068)the Water Conservancy Technology Project of Jiangsu Province of China(No.2022060)。
文摘Viscoelastic flows play an important role in numerous engineering fields,and the multiscale algorithms for simulating viscoelastic flows have received significant attention in order to deepen our understanding of the nonlinear dynamic behaviors of viscoelastic fluids.However,traditional grid-based multiscale methods are confined to simple viscoelastic flows with short relaxation time,and there is a lack of uniform multiscale scheme available for coupling different solvers in the simulations of viscoelastic fluids.In this paper,a universal multiscale method coupling an improved smoothed particle hydrodynamics(SPH)and multiscale universal interface(MUI)library is presented for viscoelastic flows.The proposed multiscale method builds on an improved SPH method and leverages the MUI library to facilitate the exchange of information among different solvers in the overlapping domain.We test the capability and flexibility of the presented multiscale method to deal with complex viscoelastic flows by solving different multiscale problems of viscoelastic flows.In the first example,the simulation of a viscoelastic Poiseuille flow is carried out by two coupled improved SPH methods with different spatial resolutions.The effects of exchanging different physical quantities on the numerical results in both the upper and lower domains are also investigated as well as the absolute errors in the overlapping domain.In the second example,the complex Wannier flow with different Weissenberg numbers is further simulated by two improved SPH methods and coupling the improved SPH method and the dissipative particle dynamics(DPD)method.The numerical results show that the physical quantities for viscoelastic flows obtained by the presented multiscale method are in consistence with those obtained by a single solver in the overlapping domain.Moreover,transferring different physical quantities has an important effect on the numerical results.
基金funded by the Serbian Ministry of Science and Technology under the project No.III 43007“Research of climate changes and their impact on environment.Monitoring of the impact,adaptation and moderation”for 2011-2014.
文摘The field of environmental sciences is abundant with various interfaces and is the right place for the application of new fundamental approaches leading towards a better understanding of environmental phenomena. Following the definition of environmental interface by Mihailovic and Bala? [1], such interface can be, for example, placed between: human or animal bodies and surrounding air, aquatic species and water and air around them, and natural or artificially built surfaces (vegetation, ice, snow, barren soil, water, urban communities) and the atmosphere, cells and surrounding environment, etc. Complex environmental interface systems are (i) open and hierarchically organised (ii) interactions between their constituent parts are nonlinear, and (iii) their interaction with the surrounding environment is noisy. These systems are therefore very sensitive to initial conditions, deterministic external perturbations and random fluctuations always present in nature. The study of noisy non-equilibrium processes is fundamental for modelling the dynamics of environmental interface regarded as biophysical complex system and for understanding the mechanisms of spatio-temporal pattern formation in contemporary environmental sciences. In this paper we will investigate an aspect of dynamics of energy flow based on the energy balance equation. The energy exchange between interacting environmen- tal interfaces regarded as biophysical complex systems can be represented by coupled maps. Therefore, we will numerically investigate coupled maps representing that exchange. In ana- lysis of behaviour of these maps we applied Lyapunov exponent and cross sample entropy.
文摘With increasing usage of a web services today, user required to consecrate reasoning energy to learning the complexities of the interface as opposed to the content. Interface complexity measures the degree of complexity encountered between the user and digital medium like website. This paper presents a New Interface Complexity (NIC) Metric, which partially based on existing schema metrics to weigh human insight of recent service interface;taking into account elements and attributes of XML documents implemented in?World Wide Web Consortium (W3C) XML Schema (WXS) to reduce the structure affecting the effort for comprehending schema documents. The NIC metric is able to draw conclusions about the perceived qualities: interoperability, extensibility and flexibility. It was discovered that there are significant correlations between NIC metric and existing measures. Automating, this practice would be beneficial to developers and designers, as it would help to provide useful feedback in software project design to check the quality of documents for easy maintenance and properly used of XML data for distributed applications.
文摘In this paper, the eigen function expansions of displacements and stresses of bi-metal laminates with interface cracks are obtained. Furthermore, the stress intensity factors are determined by the variational method to satisfy the boundary conditions and there are only line integrals in the variational equations due to the previous satisfaction of all basic equations. The computations show that this method of solution has the advantages of rapid convergency and time-saving. The results obtained by this method for homogeneous material agree with the known ones very well.
文摘We have defined the environmental interface through the exchange processes between media forming this interface. Considering the environmental interface as a complex system we elaborated the advanced mathematical tools for its modelling. We have suggested two coupled maps serving the exchange processes on the environmental interfaces spatially ranged from cellular to planetary level, i.e. 1) the map with diffusive coupling for energy exchange simulation and 2) the map with affinity, which is suitable for matter exchange processes at the cellular level. We have performed the dynamical analysis of the coupled maps using the Lyapunov exponent, cross sample as well as the permutation entropy in dependence on different map parameters. Finally, we discussed the map with affinity, which shows some features making it a promising toll in simulation of exchange processes on the environmental interface at the cellular level.
文摘The generalized two_dimensional problem of a dielectric rigid line inclusion, at the interface between two dissimilar piezoelectric media subjected to piecewise uniform loads at infinity, is studied by means of the Stroh theory. The problem was reduced to a Hilbert problem, and then closed_form expressions were obtained, respectively, for the complex potentials in piezoelectric media, the electric field inside the inclusion and the tip fields near the inclusion. It is shown that in the media, all field variables near the inclusion_tip show square root singularity and oscillatory singularity, the intensity of which is dependent on the material constants and the strains at infinity. In addition, it is found that the electric field inside the inclusion is singular and oscillatory too, when approaching the inclusion_tips from inside the inclusion.
基金Supported by the National Natural Science Foundation of China(21878144,21576130,21490584 and 21838004)Project of Jiangsu Natural Science Foundation of China(BK20171464)+2 种基金Qing Lan ProjectJiangsu Overseas Visiting Scholar Program for University Prominent Young&Middle-aged Teachers and Presidentsthe Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘In modern chemical engineering processes, solid interface involvement is the most important component of process intensification techniques, such as nanoporous membrane separation and heterogeneous catalysis. The fundamental mechanism underlying interfacial transport remains incompletely understood given the complexity of heterogeneous interfacial molecular interactions and the high nonideality of the fluid involved. Thus, understanding the effects of interface-induced fluid microstructures on flow resistance is the first step in further understanding interfacial transport. Molecular simulation has become an indispensable method for the investigation of fluid microstructure and flow resistance. Here, we reviewed the recent research progress of our group and the latest relevant works to elucidate the contribution of interface-induced fluid microstructures to flow resistance.We specifically focused on water, ionic aqueous solutions, and alcohol–water mixtures given the ubiquity of these fluid systems in modern chemical engineering processes. We discussed the effects of the interfaceinduced hydrogen bond networks of water molecules, the ionic hydration of ionic aqueous solutions, and the spatial distributions of alcohol and alcohol–water mixtures on flow resistance on the basis of the distinctive characteristics of different fluid systems.
文摘In well stimulation treatments using hydrochloric acid,undesirable water-in-oil emulsion and acid sludge may produce and then cause operational problems in oil field development.The processes intensify in the presence of Fe(Ⅲ),which are from the corroded surfaces of field equipment and/or iron-bearing minerals of the oil reservoir.In order to understand the reasons of the stability of acid emulsions,acid emulsions were prepared by mixing crude oil emulsion with 15% hydrochloric acid solutions with and without Fe(Ⅲ) and then separated into free and upper(water free) and intermediate(with water) layers.It is assumed that the oil phase of the free and upper layers contains the compounds which do not participate in the formation of acid emulsions,and the oil phase of the intermediate layers contains components involved in the formation of oil/acid interface.The composition of the oil phase of each layer of the emulsions was studied.It is found that the asphaltenes with a high content of sulfur,oxygen and metals as well the flocculated material of protonated non-polar oil components are concentrated at the oil/acid interface.In addition to the above,in the presence of Fe(Ⅲ) the Fe(Ⅲ)-based complexes with polar groups of asphaltenes are formed at the acid/oil interface,contributing to the formation of armor films which enhance the emulsion stability.
文摘The correlation between surface complexation at the SiO_(2)H_(2)O interface and quartz notation behavior was studied.Computer assisted calculations,using the programs SOLGASWATER,were adapted in order to con-struct distribution diagrams of surface speciation in the SiO_(2)-metal ion-H^(+) system in aqueous solutions.Equilib-rium constants for both surface and solution reactions were introduced in the composition matrix.Surface complexation,surface charge as well as notation results were compared and a good agreement was obtained.Furthermore,flotation mechanisms of quartz activation by common metal ions like Ca^(2+),Mg^(2+),Fe^(2+) are quantitatively discussed based on the surface reaction equilibrium constants.
文摘The generalized two-dimensional problem of a dielectric rigid line inclusion, at the interface between two dissimilar piezoelectric media subjected to piecewise uniform loads at infinity, is studied by means of the Stroh theory. The problem was reduced to a Hilbert problem, and then closed-form expressions were obtained, respectively, far the complex potentials in piezoelectric media, the electric field inside the inclusion and the tip fields near the inclusion. it is shown that in the media, all field variables near the inclusion-tip show square root singularity and oscillatory singularity, the intensity of which is dependent on the material constants and the strains at infinity. In addition, it is found that the electric field inside the inclusion is singular and oscillatory too, when approaching the inclusion-tips from inside the inclusion.
文摘By the theory of complex functions, the dynamic propagation problem on Dugdale model of mode Ⅲ interface crack for nonlinear characters of materials was studied. The general expressions of analytical solutions are obtained by the methods of self-similar functions. The problems dealt with can be easily transformed into Riemann-Hilbert problems and their closed solutions are attained rather simply by this approach. After those solutions were utilized by superposition theorem, the solutions of arbitrarily complex problems could be obtained.
基金Project supported by the Postdoctoral Science Foundation of China (No.2005038199)the Natural Science Foundation of Heilongjiang Province of China (No.ZJG04-08)
文摘By the application of the theory of complex functions, asymmetrical dynamic propagation problems on mode Ⅲ interface crack are studied. The universal representations of analytical solutions are obtained by the approaches of self-similar function. The problems researched can be facilely transformed into Riemann-Hilbert problems and analytical solution to an asymmetrical propagation crack under the condition of point loads and unit-step loads, respectively, is acquired. After those solutions were used by superposition theorem, the solutions of arbitrarily complex problems could be attained.
基金supported by the National Natural Science Foundation of China(11172094 and 11172095)the NCET-11-0122 and Hunan Provincial Natural Science Foundation for Creative Research Groups of China(12JJ7001)
文摘Interface imperfection can significantly affect the mechanical properties and failure mechanisms as well as the strength and toughness of nanocomposites. The elastic behavior of a screw dislocation in nanoscale coating with imperfect interface is studied in the three-phase composite cylinder model. The interface between inner nanoin- homogeneity and intermediate coating is assumed as perfectly bonded. The bonding between intermediate coating and outer matrix is considered to be imperfect with the assumption that interface imperfection is uniform, and a linear spring model is adopted to describe the weakness of imperfect interface. The explicit expression for image force acting on dislocation is obtained by means of a complex variable method. The analytic results indicate that inner interface effect and outer interface imperfection, simultaneously taken into account, would influence greatly image force, equilibrium position and stability of dislocation, and various critical parameters that would change dislocation stability. The weaker interface is a very strong trap for glide dislocation and, thus, a more effective barrier for slip transmission.
基金Project supported by the National Natural Science Foundation of China(Grant No.51673214)the National Key Research and Development Program of China(Grant No.2017YFA0206600)。
文摘The morphology and interface of perovskite film are very important for the performance of perovskite solar cells(PSCs).The quality of perovskite film,fabricated via two-step spin-coating process,is significantly influenced by the morphology and crystallinity of PbI2 film.With the addition of additive dimethyl sulfoxide(DMSO)into the PbI2 precursor,the roughness and trap-state density of perovskite film have been significantly reduced,leading to the excellent contact between perovskite layer and subsequent deposited carrier transport layer.Accordingly,the planar heterojunction PSCs with an architecture of ITO/SnO2/perovskite/PTAA/Ag show an efficiency up to 19.02%.Furthermore,PSCs exhibit promising stability in air with a humidity of ~45%,and retain 80% of initial efficiency after being exposed to air for 400 h without any encapsulation.
文摘Protein-protein complexes play an important role in the physiology and the pathology of cellular functions, and therefore are attractive therapeutic targets. A small subset of residues known as “hot spots”, accounts for most of the protein-protein binding free energy. Computational methods play a critical role in identifying the hotspots on the proteinprotein interface. In this paper, we use a computational alanine scanning method with all-atom force fields for predicting hotspots for 313 mutations in 16 protein complexes of known structures. We studied the effect of force fields, solvation models, and conformational sampling on the hotspot predictions. We compared the calculated change in the protein-protein interaction energies upon mutation of the residues in and near the protein-protein interface, to the experimental change in free energies. The AMBER force field (FF) predicted 86% of the hotspots among the three commonly used FF for proteins, namely, AMBER FF, Charmm27 FF, and OPLS-2005 FF. However, AMBER FF also showed a high rate of false positives, while the Charmm27 FF yielded 74% correct predictions of the hotspot residues with low false positives. Van der Waals and hydrogen bonding energy show the largest energy contribution with a high rate of prediction accuracy, while the desolvation energy was found to contribute little to improve the hot spot prediction. Using a conformational ensemble including limited backbone movement instead of one static structure leads to better predicttion of hotpsots.