Spatial confinement of block copolymers can induce frustrations,which can further be utilized to regulate self-assembled structures,thus providing an efficient route for fabricating novel structures.We studied the sel...Spatial confinement of block copolymers can induce frustrations,which can further be utilized to regulate self-assembled structures,thus providing an efficient route for fabricating novel structures.We studied the self-assembly of AB di-block copolymers(di-BCPs)confined in Janus spherical nanocavities using simulations,and explained the structure formation mechanisms.In the case of a strongly selective cavity wall,all the lamella-forming,gyroid-forming,and cylinder-forming di-BCPs can form interfacial frustration-induced Janus concentric perforated lamellar nanoparticles,whose outermost is a Janus spherical shell and the internal is a sphere with concentric perforated lamellar structure.In particular,Janus concentric perforated lamellar nanoparticles with holes distributed only near the equatorial plane were obtained in both lamella-forming and gyroid-forming di-BCPs,directly reflecting the effect of interfacial frustration.The minority-block domain of the cylider-forming di-BCPs may form hemispherical perforated lamellar structures with holes distributed in parallel layers with a specific orientation.For symmetric di-BCPs,both the A and B domains in each nanoparticle are continuous,interchangeable,and have rotational symmetry.While for gyroid-forming and cylinder-forming di-BCPs,only the majority-block domains are continuous in each nanoparticle,and holes in the minority-block domains usually have rotational symmetry.In the case of a weakly selective cavity wall,the inhomogeneity of the cavity wall results in structures having a specific orientation(such as flower-like and branched structures in gyroid-forming and cylinder-forming di-BCPs)and a perforated wetting layer with uniformly distributed holes.The novel nanoparticles obtained may have potential applications in nanotechnology as functional nanostructures or nanoparticles.展开更多
Chiral active matter exhibits a variety of collective behaviors,including phase separation,which is governed by the rule of“like chiralities attract,while opposite chiralities repel”.In this work,we investigate the ...Chiral active matter exhibits a variety of collective behaviors,including phase separation,which is governed by the rule of“like chiralities attract,while opposite chiralities repel”.In this work,we investigate the chiral demixing strategy of double-chiral partial mixture with inter-chiral frustration.We find that the inter-chiral frustration can significantly enhance the chiral demixing of active particles with different chiralities,both during the transient and in the steady state,not only accelerating the progress,but also improving the degree of phase separation.This phenomenon is reminiscent of the phase separation of binary mixtures in condensed matter physics,where the inter-chiral frustration can play a crucial role in the formation of the phase-separated states.We construct the phase diagram of the system and discuss the critical frustration for the enhancement of chiral demixing.Our work presents the first systematic investigation of inter-chiral frustration in self-propelled chiral active matter,filling a critical gap in the field.展开更多
We synthesized a quasi-two-dimensional distorted triangular lattice antiferromagnet Ca3CoNb2O9, in which the effective spin of Co2＋is 1/2 at low temperatures, whose magnetic properties were studied by dc susceptibili...We synthesized a quasi-two-dimensional distorted triangular lattice antiferromagnet Ca3CoNb2O9, in which the effective spin of Co2＋is 1/2 at low temperatures, whose magnetic properties were studied by dc susceptibility and magnetization techniques. The x-ray diffraction confirms the quality of our powder samples. The large Weiss constant θCW --55 K and the low Neel temperature TN- 1.45 K give a frustration factor f =｜ θCW/TN｜≈ 38, suggesting that Ca3 Co Nb2O9resides in strong frustration regime. Slightly below TN, deviation between the susceptibility data under zero-field cooling（ZFC）and field cooling（FC） is observed. A new magnetic state with 1/3 of the saturate magnetization Ms is suggested in the magnetization curve at 0.46 K. Our study indicates that Ca3 Co Nb2O9is an interesting material to investigate magnetism in triangular lattice antiferromagnets with weak anisotropy.展开更多
The doping effects on the frustration and the magnetic properties in hexagonal compounds ot YMn0.9A0.1O3 （A=A1, Fe and Cu） are investigated. Experimental results indicate that both the non-magnetic and magnetic ion ...The doping effects on the frustration and the magnetic properties in hexagonal compounds ot YMn0.9A0.1O3 （A=A1, Fe and Cu） are investigated. Experimental results indicate that both the non-magnetic and magnetic ion dopants lead to the increase of magnetic moments and the decrease of the absolute value of Curie-Weiss temperature （｜θcw｜）- Compared with pure YMnOa, the geometrical frustration of YMn0.9 A0. 1O3 is greatly suppressed and the magnetic coupling in that exhibits dopant-dependent. In addition, for the doped YMno.gAo.103, the antiferromagnetic transition temperature （TN） is also suppressed slightly, which shows an abnormal dilution effect and it may be ascribed to the reduction of frustration due to the chemical substitution.展开更多
Background Although frustration is a common emotional reaction while playing games,an excessive level of frustration can negatively impact a user's experience,discouraging them from further game interactions.The a...Background Although frustration is a common emotional reaction while playing games,an excessive level of frustration can negatively impact a user's experience,discouraging them from further game interactions.The automatic detection of frustration can enable the development of adaptive systems that can adapt a game to a user's specific needs through real-time difficulty adjustment,thereby optimizing the player's experience and guaranteeing game success.To this end,we present a speech-based approach for the automatic detection of frustration during game interactions,a specific task that remains under explored in research.Method The experiments were performed on the Multimodal Game Frustration Database(MGFD),an audiovisual dataset-collected within the Wizard-of-Oz framework-that is specially tailored to investigate verbal and facial expressions of frustration during game interactions.We explored the performance of a variety of acoustic feature sets,including Mel-Spectrograms,Mel Frequency Cepstral Coefficients(MFCCs),and the low-dimensional knowledge-based acoustic feature set eGeMAPS.Because of the continual improvements in speech recognition tasks achieved by the use of convolutional neural networks(CNNs),unlike the MGFD baseline,which is based on the Long Short Term Memory(LSTM)architecture and Support Vector Machine(SVM)classifier-in the present work,we consider typical CNNs,including ResNet,VGG,and AlexNet.Furthermore,given the unresolved debate on the suitability of shallow and deep networks,we also examine the performance of two of the latest deep CNNs:WideResNet and EfficientNet.Results Our best result,achieved with WideResNet and Mel-Spectrogram features,increases the system performance from 58.8%unweighted average recall(UAR)to 93.1%UAR for speech-based automatic frustration recognition.展开更多
In this study, a T-maze-based frustration model in rats was established using sucrose-reward deprivation, The results revealed that rats maintained a 75% preference for the sucrose-reward arm in the reward phase. Duri...In this study, a T-maze-based frustration model in rats was established using sucrose-reward deprivation, The results revealed that rats maintained a 75% preference for the sucrose-reward arm in the reward phase. During the sucrose-deprivation frustration phase, both the preference for the sucrose-deprivation arm （62.5%） and time spent waiting in the sucrose-deprivation arm decreased. Acute injection of morphine increased the preference in a dose-dependent fashion, and prolonged the waiting duration in the sucrose-deprivation arm. These findings indicate that morphine specifically inhibited the frustration response induced by sucrose reward deprivation. To further elucidate the pharmacological mechanisms involved, the opioid receptor antagonist naloxone was given to model rats prior to the injection of morphine. The results revealed that naloxone administration markedly attenuated the anti-frustration-like effects of 3 mg/kg morphine treatment. These findings suggest that morphine attenuates the frustration-like response to reward deprivation in rats through the opioid receptor.展开更多
To study the effects of lanthanide ions on the geometrically frustrated antiferromagnets and their magnetic properties,we grew high-quality single crystals of LnCu_(3)(OH)_(6)Br_(3)(Ln=Nd,Sm,and Eu)by hydrothermal met...To study the effects of lanthanide ions on the geometrically frustrated antiferromagnets and their magnetic properties,we grew high-quality single crystals of LnCu_(3)(OH)_(6)Br_(3)(Ln=Nd,Sm,and Eu)by hydrothermal method and studied their crystal structures and magnetic properties.The refinements of the crystal structure referred to the powder x-ray diffraction data show that LnCu_(3)(OH)_(6)Br_(3)adopt a Kapellasite-type layer structure,which is isostructural to their chlorine analogue.Magnetic susceptibilities demonstrate that LnCu_(3)(OH)_(6)Br_(3)have strong antiferromagnetic coupling and a pronounced magnetic frustration effect.Magnetization measurements indicate canted antiferromagnetic ordering of Cu^(2+)ions around 16 K within the kagoméplane and weak ferromagnetic coupling.Moreover,shoulder-like anomalies in specific heat around 16 K could be a signature of emergent of magnetic ordering.The low-temperature negative magnetization and specific heat of LnCu_(3)(OH)_(6)Br_(3)(Ln=Nd,Sm,and Eu)indicate that Ln^(3+)ions induce more exotic magnetic ground state properties.展开更多
This paper studies a spin ladder model which possesses frustrating interactions. By using both the bosonization and the density matrix renormalization group techniques, it shows that the intermediate columnar dimerize...This paper studies a spin ladder model which possesses frustrating interactions. By using both the bosonization and the density matrix renormalization group techniques, it shows that the intermediate columnar dimerized phase, which exists in a narrow parameter region of the so-called ~/1 - J2 model, vanishes if the interchain frustration is weak and anisotropic. Therefore, it concludes that the frustrating interaction indeed plays an important role in producing such a phase. As a complementary to our previous investigation, it reaches a more complete picture of the quantum phase transition in the frustrated spin ladder systems.展开更多
Energy storage units are essential in electronic and electric devices as sources to supply energy for circuits.The most widely used ones are electrochemical batteries with high energy density,for example,in renewable ...Energy storage units are essential in electronic and electric devices as sources to supply energy for circuits.The most widely used ones are electrochemical batteries with high energy density,for example,in renewable energy generation and electric vehicles.However,the electrochemical batteries cannot suffer highpower energy input/output,limiting their applications in scenarios that requires ultrafast charging/discharging,such as pulsed lasers and ignition.In this regard,dielectric electrostatic capacitors are indispensable[1,2].展开更多
The aim of this study was to evaluate the relationship between frustration education and frustration level of middle school students in a city during the 2022-2023 school year.Descriptive correlation analysis was appl...The aim of this study was to evaluate the relationship between frustration education and frustration level of middle school students in a city during the 2022-2023 school year.Descriptive correlation analysis was applied to 270 students.Chi-square is a statistical tool used in the study.According to the findings,there are more women than men,and most are from rural areas.The findings suggest that understanding the significant correlation between frustration and educational assessments of social dimensions and overall frustration can provide insight into potential areas for intervention and support.While the academic and instructional dimensions may not be directly related to the level of frustration in this study,it is important to explore other factors that may be contributing to academic frustration or areas where instructional strategies could be improved.A social skills development program aims to address this problem.展开更多
Frustrated lanthanide oxides with dense magnetic lattice and suppressed ordering temperature have potential applications in cryogenic magnetic refrigeration.Herein,the crystal structure,magnetic properties,magnetic ph...Frustrated lanthanide oxides with dense magnetic lattice and suppressed ordering temperature have potential applications in cryogenic magnetic refrigeration.Herein,the crystal structure,magnetic properties,magnetic phase transition(MPT)together with magnetocaloric effect(MCE)of LnOF(Ln=Gd,Dy,Ho,and Er)compounds were investigated.Crystallographic study shows that these compounds crystallize in the centrosymmetric space group R3m with an ideal triangular lattice.No long-range magnetic ordering is observed above 2 K for LnOF(Ln=Gd,Ho,and Er).However,DyOF compound undergoes an MPT from paramagnetic(PM)to antiferromagnetic(AFM)at the Neel temperature(TN≈4 K).Considerable reversible MCE is observed in these triangular-lattice compounds.Under the magnetic field change(μ0ΔH)of 0-2 T,the maximum values of magnetic entropy change(-ΔSMmax)of them are 6.1,9.4,12.7,and 14.1 J/(kg·K),respectively.Interestingly,the value of ErOF with Ising-like spin is 2.3 times that of GdOF,which provides an approach for exploring magnetic refrigerants with excellent low-field cryogenic magnetocaloric effect.展开更多
In this study, we consider the emergence of explosive synchronization in scale-free networks by considering the Kuramoto model of coupled phase oscillators. The natural frequencies of oscillators are assumed to be cor...In this study, we consider the emergence of explosive synchronization in scale-free networks by considering the Kuramoto model of coupled phase oscillators. The natural frequencies of oscillators are assumed to be correlated with their degrees and frustration is included in the system. This assumption can enhance or delay the explosive transition to synchronization. Interestingly, a de-synchronization phenomenon occurs and the type of phase transition is also changed. Furthermore, we provide an analytical treatment based on a star graph, which resembles that obtained in scale-free networks. Finally, a self-consistent approach is implemented to study the de-synchronization regime. Our findings have important implications for controlling synchronization in complex networks because frustration is a controllable parameter in experiments and a discontinuous abrupt phase transition is always dangerous in engineering in the real world.展开更多
Few jobs come without irritations, and foreign language instruction comes with its own particular set of frustrations which, when accumulated, can lead to stress and eventual burnout for teachers.One mechanism for red...Few jobs come without irritations, and foreign language instruction comes with its own particular set of frustrations which, when accumulated, can lead to stress and eventual burnout for teachers.One mechanism for reducing such frustrations is that of emotion regulation, the cognitive and behavioral strategies individuals employ to manage the emotions they experience or display. To date,no known studies have reported specifically on the in-class frustration experienced by language teachers, or on how teachers regulate their feelings of frustration. Herein, the authors discuss the experiences of seven EFL teachers at a university in Japan obtained through a series of semistructured interviews, classroom observations and corresponding stimulated-recall sessions. The authors discuss four salient thematic frustrations: student apathy, classroom silence, misbehavior in the context of relational strain, and working conditions. The results reveal that participants applied contextually-dependent emotion regulation behaviors, the success of which was often contingent on the participants’ levels of confidence and control over the stressors. Thus, participants showed more success in managing pervasive low-level stressors such as apathy and silence, and more support would be welcome to aid them to manage more debilitating stressors such as student misbehavior.The authors offer suggestions for teachers, trainers and institutions on reducing frustration.展开更多
The concept of"packing frustration"has been used to understand the self-assembly behaviors of block copolymers for decades.However,rare attention has been paid to tailoring the packing frustration.This accou...The concept of"packing frustration"has been used to understand the self-assembly behaviors of block copolymers for decades.However,rare attention has been paid to tailoring the packing frustration.This account provides a review of our recent endeavor of controlling the self-assembly of block copolymers via tailoring the packing frustration.The basic idea is to release the packing frustration of chains through the local segregation between different blocks of the same component filing different spaces of near and far.Two different majority blocks are designed to release their packing frustration in the matrix.In particular,this effect of released packing frustration has been successfullycombined with other effectss such as the stretched bridging block to stabilize many unusual low.coordinated phases.We have also proposed to release the packing frustration of minority blocks within the interface curva-ture by designing the architectures of minority blocks.The effect of released packing frustration of minority blocks is aplied to drastically expand the region of spherical phases and thus to obtain significant regions of complex Frank Kasper phases.In brief,the self.assembly of block copolymers can be largely contrlled by tailoring the packing frustration of blocks,even leading to the formation of many unusual ordered phases.展开更多
Heterogeneous solid frustrated-Lewis-pair(FLP)catalyst is of great promise in practical hydrogenation applications.It has been found that all-solid FLPs can be created on ceria via surface oxygen vacancy regulation.Co...Heterogeneous solid frustrated-Lewis-pair(FLP)catalyst is of great promise in practical hydrogenation applications.It has been found that all-solid FLPs can be created on ceria via surface oxygen vacancy regulation.Consequently,it is desired to investigate the mechanisms of the FLP-catalyzed hydrogenation of C=C and C=O and provide insight into the modification of CeO_(2)catalysts for the selective hydrogenation.In this work,the reaction mechanism of the hydrogenation of CH_(2)=CH_(2)and CH_(3)CH=O at the FLP sites constructed on CeO_(2)(110)surface was investigated by density functional theory(DFT),with the classical Lewis acid-base pairs(CLP)site as the reference.The results illustrate that at the CLP site,the dissociated hydride(H^(δ−))forms a stable H−O bond with the surface O atom,while at the FLP site,H^(δ−)is stabilized by Ce,displaying higher activity on the one hand.On the other hand,the electron cloud density of the Ce atom at the FLP site is higher,which can transfer more electrons to the adsorbed C_(C=C)and O_(C=O)atoms,leading to a higher degree of activation for C=C and C=O bonds,as indicated by the Bader charge analysis.Therefore,compared to the CLP site,the FLP site exhibits higher hydrogenation activity for CH_(2)=CH_(2)and CH_(3)CH=O.Furthermore,at the FLP sites,it demonstrates high efficiency in catalyzing the hydrogenation of CH_(2)=CH_(2)with the rate-determining barrier of 1.04 eV,but it shows limited activity for the hydrogenation of CH_(3)CH=O with the rate-determining barrier of 1.94 eV.It means that the selective hydrogenation of C=C can be effectively achieved at the FLP sites concerning selective hydrogenation catalysis.The insights shown in this work help to clarify the reaction mechanism of the hydrogenation of C=C and C=O at FLP site on CeO_(2)(110)and reveal the relationship between the catalytic performance and the nature of the active site,which is of great benefit to development of rational design of heterogeneous FLP catalysts.展开更多
The development of solid frustrated Lewis pairs(FLPs)catalysts with porous structures is a promising strategy for advancing green hydrogenation technologies and has garnered significant attention.Leveraging the divers...The development of solid frustrated Lewis pairs(FLPs)catalysts with porous structures is a promising strategy for advancing green hydrogenation technologies and has garnered significant attention.Leveraging the diverse oxidation states and structural tunability of cerium-based metal-organic frameworks(Ce-MOFs),this study employed a competitive coordination strategy utilizing a single carboxylate functional group ligand to construct a series of MOF-808-X(X=-NH_(2),-OH,-Br,and-NO_(2))featuring rich solid-state FLPs for hydrogenation of unsaturated olefins.The-X functional group serves as a microenvironment,enhancing hydrogenation activity by modulating the electronic properties and acid-base characteristics of the FLP sites.The unique redox properties of elemental cerium facilitate the exposure of unsaturated Ce sites(Ce-CUS,Lewis acid(LA))and adjacent Ce-OH(Lewis base(LB))sites within the MOFs,generating abundant solid-state FLP(Ce-CUS/Ce-OH)sites.Experimental results demonstrate that Ce-CUS and Ce-OH interact with theσandσ^(*)orbitals of H-H,and this"push-pull"synergy promotes heterolytic cleavage of the H-H bond.The lone pair electrons of the electron-donating functional group are transmitted through the molecular backbone to the LB site,thereby increasing its strength and reducing the activation energy required for H_(2)heterolytic cleavage.Notably,at 100℃and 2 MPa H_(2),MOF-808-NH_(2)achieves complete conversion of styrene and dicyclopentadiene,significantly outperforming MOF-808.Based on in-situ analysis and density functional theory calculations,a plausible reaction mechanism is proposed.This research enriches the theoretical framework for unsaturated olefin hydrogenation catalysts and contributes to the development of efficient catalytic systems.展开更多
Long-cycling dendrite-free solid-state lithium metal batteries (LMBs) require fast and uniform lithium-ion (Liþ)transport of solid-state electrolytes (SSEs). However, the SSEs still face the problems of low ionic...Long-cycling dendrite-free solid-state lithium metal batteries (LMBs) require fast and uniform lithium-ion (Liþ)transport of solid-state electrolytes (SSEs). However, the SSEs still face the problems of low ionic conductivity, lowLiþ transference number, and unstable interface with lithium metal. In this work, a novel strategy of frustratedLewis pairs (FLPs) modulating solid polymer electrolytes (SPEs) has been firstly proposed that enables durable Lireversible cycling. The tunable strength of Lewis acid and base dual-active sites of nickel borate FLPs can syn-ergisticallypromote both the dissociation of lithium salts and the transfer of Liþ. As a consequence, the FLPsmodulated SPEs (SPE-NiBO-150) exhibit high ionic conductivity of 4.92×10^(-4)S cm^(-1), high Liþ transferencenumber of 0.74, and superior interface compatibility with both lithium anode and LiFePO4 cathode at room-temperature.The Li//SPE-NiBO-150//Li symmetric cell demonstrates ultralong cycle stability (over 10,000 h(417 days) at both current density of 0.2 and 0.5 mA cm〓〓2), and the assembled solid-state LiFePO4//SPE-NiBO-150//Libattery also shows excellent performance (86% capacity retention for 300 cycles at 0.5C). The presentwork supplies a new insight into designing high-performance SPEs for solid-state LMB applications.展开更多
One-step direct production of methanol from methane and water(PMMW)under mild conditions is challenging in heterogeneous catalysis owing to the absence of highly effective catalysts.Herein,we designed a series of“Sin...One-step direct production of methanol from methane and water(PMMW)under mild conditions is challenging in heterogeneous catalysis owing to the absence of highly effective catalysts.Herein,we designed a series of“Single-Atom”-“Frustrated Lewis Pair”(SA-FLP)dual active sites for the direct PMMW via density functional theory(DFT)calculations combined with a machine learning(ML)approach.The results indicate that the nine designed SA-FLP catalysts are capable of efficiently activate CH4 and H_(2)O and facilitate the coupling of OH^(*)and CH_(3)^(*)into methanol.The DFT-based microkinetic simulation(MKM)results indicate that CH_(3)OH production on Co1-FLP and Pt1-FLP catalysts can reach the turnover frequencies(TOFs)of 1.01×10^(−3)s^(-1)and 8.80×10^(−4)s^(-1),respectively,which exceed the experimentally reported values by three orders of magnitude.ML results unveil that the gradient boosted regression model with 13 simple features could give satisfactory predictions for the TOFs of CH_(3)OH production with RMSE and R^(2)of 0.009 s^(-1)and 1.00,respectively.The ML-predicted MKM results indicate that four catalysts including V_(1-),Fe_(1-),Ti_(1-),and Mn_(1)-FLP exhibit higher TOFs of CH_(3)OH production than the value that the most relevant experiments reported,indicating that the four catalysts are also promising catalysts for the PMMW.This study not only develops a simple and efficient approach for design and screening SA-FLP catalysts but also provides mechanistic insights into the direct PMMW.展开更多
We extend a semiclassical numerical method, bosonic auxiliary-field Monte Carlo, to quantum spin systems. This method breaks the lattice into clusters, solves each cluster precisely and couples them with classical aux...We extend a semiclassical numerical method, bosonic auxiliary-field Monte Carlo, to quantum spin systems. This method breaks the lattice into clusters, solves each cluster precisely and couples them with classical auxiliary fields through classical Monte Carlo simulation. We test the method with antiferromagnetic spin models in one-dimensional chains, square lattices and triangular lattices, and obtain reasonable results at finite temperatures. This algorithm builds a bridge between classical Monte Carlo method and quantum methods. The algorithm can be improved with either progress in classical Monte Carlo sampling or the development of quantum solvers, and can also be further applied to systems with different lattices or interactions.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.22173051,21829301,21774066)College Discipline Innovation and Intelligence Introduction Program(111 Project(B16027)+1 种基金the International Cooperation Base(2016D01025)Tianjin International Joint Research and Development Center。
文摘Spatial confinement of block copolymers can induce frustrations,which can further be utilized to regulate self-assembled structures,thus providing an efficient route for fabricating novel structures.We studied the self-assembly of AB di-block copolymers(di-BCPs)confined in Janus spherical nanocavities using simulations,and explained the structure formation mechanisms.In the case of a strongly selective cavity wall,all the lamella-forming,gyroid-forming,and cylinder-forming di-BCPs can form interfacial frustration-induced Janus concentric perforated lamellar nanoparticles,whose outermost is a Janus spherical shell and the internal is a sphere with concentric perforated lamellar structure.In particular,Janus concentric perforated lamellar nanoparticles with holes distributed only near the equatorial plane were obtained in both lamella-forming and gyroid-forming di-BCPs,directly reflecting the effect of interfacial frustration.The minority-block domain of the cylider-forming di-BCPs may form hemispherical perforated lamellar structures with holes distributed in parallel layers with a specific orientation.For symmetric di-BCPs,both the A and B domains in each nanoparticle are continuous,interchangeable,and have rotational symmetry.While for gyroid-forming and cylinder-forming di-BCPs,only the majority-block domains are continuous in each nanoparticle,and holes in the minority-block domains usually have rotational symmetry.In the case of a weakly selective cavity wall,the inhomogeneity of the cavity wall results in structures having a specific orientation(such as flower-like and branched structures in gyroid-forming and cylinder-forming di-BCPs)and a perforated wetting layer with uniformly distributed holes.The novel nanoparticles obtained may have potential applications in nanotechnology as functional nanostructures or nanoparticles.
基金supported by the National Natural Science Foun-dation of China(Grant Nos.12375031 and 11875135)China National University Student Innovation and Entrepreneurship(Grant No.202410385040)Fujian University Alliance of Physics Discipline Training Program of Innovation for Under-graduates Development Program,China.
文摘Chiral active matter exhibits a variety of collective behaviors,including phase separation,which is governed by the rule of“like chiralities attract,while opposite chiralities repel”.In this work,we investigate the chiral demixing strategy of double-chiral partial mixture with inter-chiral frustration.We find that the inter-chiral frustration can significantly enhance the chiral demixing of active particles with different chiralities,both during the transient and in the steady state,not only accelerating the progress,but also improving the degree of phase separation.This phenomenon is reminiscent of the phase separation of binary mixtures in condensed matter physics,where the inter-chiral frustration can play a crucial role in the formation of the phase-separated states.We construct the phase diagram of the system and discuss the critical frustration for the enhancement of chiral demixing.Our work presents the first systematic investigation of inter-chiral frustration in self-propelled chiral active matter,filling a critical gap in the field.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11374364 and 11222433)the National Basic Research Program of China(Grant No.2011CBA00112)+2 种基金Research at Mc Master University supported by the Natural Sciences and Engineering Research CouncilWork at North China Electric Power University supported by the Scientific Research Foundation for the Returned Overseas Chinese ScholarsState Education Ministry
文摘We synthesized a quasi-two-dimensional distorted triangular lattice antiferromagnet Ca3CoNb2O9, in which the effective spin of Co2＋is 1/2 at low temperatures, whose magnetic properties were studied by dc susceptibility and magnetization techniques. The x-ray diffraction confirms the quality of our powder samples. The large Weiss constant θCW --55 K and the low Neel temperature TN- 1.45 K give a frustration factor f =｜ θCW/TN｜≈ 38, suggesting that Ca3 Co Nb2O9resides in strong frustration regime. Slightly below TN, deviation between the susceptibility data under zero-field cooling（ZFC）and field cooling（FC） is observed. A new magnetic state with 1/3 of the saturate magnetization Ms is suggested in the magnetization curve at 0.46 K. Our study indicates that Ca3 Co Nb2O9is an interesting material to investigate magnetism in triangular lattice antiferromagnets with weak anisotropy.
基金Supported by the National Natural Science Foundation of China under Grant No 11104091
文摘The doping effects on the frustration and the magnetic properties in hexagonal compounds ot YMn0.9A0.1O3 （A=A1, Fe and Cu） are investigated. Experimental results indicate that both the non-magnetic and magnetic ion dopants lead to the increase of magnetic moments and the decrease of the absolute value of Curie-Weiss temperature （｜θcw｜）- Compared with pure YMnOa, the geometrical frustration of YMn0.9 A0. 1O3 is greatly suppressed and the magnetic coupling in that exhibits dopant-dependent. In addition, for the doped YMno.gAo.103, the antiferromagnetic transition temperature （TN） is also suppressed slightly, which shows an abnormal dilution effect and it may be ascribed to the reduction of frustration due to the chemical substitution.
基金the European Union's Horizon 2020 Programmes Under Grant Agreement(826506,sustAGE).
文摘Background Although frustration is a common emotional reaction while playing games,an excessive level of frustration can negatively impact a user's experience,discouraging them from further game interactions.The automatic detection of frustration can enable the development of adaptive systems that can adapt a game to a user's specific needs through real-time difficulty adjustment,thereby optimizing the player's experience and guaranteeing game success.To this end,we present a speech-based approach for the automatic detection of frustration during game interactions,a specific task that remains under explored in research.Method The experiments were performed on the Multimodal Game Frustration Database(MGFD),an audiovisual dataset-collected within the Wizard-of-Oz framework-that is specially tailored to investigate verbal and facial expressions of frustration during game interactions.We explored the performance of a variety of acoustic feature sets,including Mel-Spectrograms,Mel Frequency Cepstral Coefficients(MFCCs),and the low-dimensional knowledge-based acoustic feature set eGeMAPS.Because of the continual improvements in speech recognition tasks achieved by the use of convolutional neural networks(CNNs),unlike the MGFD baseline,which is based on the Long Short Term Memory(LSTM)architecture and Support Vector Machine(SVM)classifier-in the present work,we consider typical CNNs,including ResNet,VGG,and AlexNet.Furthermore,given the unresolved debate on the suitability of shallow and deep networks,we also examine the performance of two of the latest deep CNNs:WideResNet and EfficientNet.Results Our best result,achieved with WideResNet and Mel-Spectrogram features,increases the system performance from 58.8%unweighted average recall(UAR)to 93.1%UAR for speech-based automatic frustration recognition.
基金the National Natural Science Foundation of China,No.30870894the National Basic Research Program of China,No.2009CB522000National Key Technology R&D Program in the 12th Five-Year Plan of China,No.2011BAK04B08
文摘In this study, a T-maze-based frustration model in rats was established using sucrose-reward deprivation, The results revealed that rats maintained a 75% preference for the sucrose-reward arm in the reward phase. During the sucrose-deprivation frustration phase, both the preference for the sucrose-deprivation arm （62.5%） and time spent waiting in the sucrose-deprivation arm decreased. Acute injection of morphine increased the preference in a dose-dependent fashion, and prolonged the waiting duration in the sucrose-deprivation arm. These findings indicate that morphine specifically inhibited the frustration response induced by sucrose reward deprivation. To further elucidate the pharmacological mechanisms involved, the opioid receptor antagonist naloxone was given to model rats prior to the injection of morphine. The results revealed that naloxone administration markedly attenuated the anti-frustration-like effects of 3 mg/kg morphine treatment. These findings suggest that morphine attenuates the frustration-like response to reward deprivation in rats through the opioid receptor.
基金Project supported by the Natural Science Foundation of Anhui Province,China(Grant Nos.2108085MA16 and2108085QA22)the Key Project of Anhui Provincial Department of Education(Grant No.KJ2020A0013)+1 种基金the Key Project of the Foundation of Anhui Education Committee,China(Grant No.2022AH050066)the National Natural Science Foundation of China(Grant Nos.U1832209,11874336,12274338,12104010,12104011,52102333,and 12004003)。
文摘To study the effects of lanthanide ions on the geometrically frustrated antiferromagnets and their magnetic properties,we grew high-quality single crystals of LnCu_(3)(OH)_(6)Br_(3)(Ln=Nd,Sm,and Eu)by hydrothermal method and studied their crystal structures and magnetic properties.The refinements of the crystal structure referred to the powder x-ray diffraction data show that LnCu_(3)(OH)_(6)Br_(3)adopt a Kapellasite-type layer structure,which is isostructural to their chlorine analogue.Magnetic susceptibilities demonstrate that LnCu_(3)(OH)_(6)Br_(3)have strong antiferromagnetic coupling and a pronounced magnetic frustration effect.Magnetization measurements indicate canted antiferromagnetic ordering of Cu^(2+)ions around 16 K within the kagoméplane and weak ferromagnetic coupling.Moreover,shoulder-like anomalies in specific heat around 16 K could be a signature of emergent of magnetic ordering.The low-temperature negative magnetization and specific heat of LnCu_(3)(OH)_(6)Br_(3)(Ln=Nd,Sm,and Eu)indicate that Ln^(3+)ions induce more exotic magnetic ground state properties.
基金supported by the National Natural Science Foundation of China (Grant No. 10874003)Ministry of Science and Technology of China (Grant No. 2006CB921300)
文摘This paper studies a spin ladder model which possesses frustrating interactions. By using both the bosonization and the density matrix renormalization group techniques, it shows that the intermediate columnar dimerized phase, which exists in a narrow parameter region of the so-called ~/1 - J2 model, vanishes if the interchain frustration is weak and anisotropic. Therefore, it concludes that the frustrating interaction indeed plays an important role in producing such a phase. As a complementary to our previous investigation, it reaches a more complete picture of the quantum phase transition in the frustrated spin ladder systems.
文摘Energy storage units are essential in electronic and electric devices as sources to supply energy for circuits.The most widely used ones are electrochemical batteries with high energy density,for example,in renewable energy generation and electric vehicles.However,the electrochemical batteries cannot suffer highpower energy input/output,limiting their applications in scenarios that requires ultrafast charging/discharging,such as pulsed lasers and ignition.In this regard,dielectric electrostatic capacitors are indispensable[1,2].
文摘The aim of this study was to evaluate the relationship between frustration education and frustration level of middle school students in a city during the 2022-2023 school year.Descriptive correlation analysis was applied to 270 students.Chi-square is a statistical tool used in the study.According to the findings,there are more women than men,and most are from rural areas.The findings suggest that understanding the significant correlation between frustration and educational assessments of social dimensions and overall frustration can provide insight into potential areas for intervention and support.While the academic and instructional dimensions may not be directly related to the level of frustration in this study,it is important to explore other factors that may be contributing to academic frustration or areas where instructional strategies could be improved.A social skills development program aims to address this problem.
基金Project supported by the National Key Research and Development Program of China(2022YFB3505101)the National Science Foundation for Excellent Young Scholars(52222107)+2 种基金the National Science Foundation for Distinguished Young Scholars(51925605)the National Natural Science Foundation of China(52171195)the Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences(E055B002)。
文摘Frustrated lanthanide oxides with dense magnetic lattice and suppressed ordering temperature have potential applications in cryogenic magnetic refrigeration.Herein,the crystal structure,magnetic properties,magnetic phase transition(MPT)together with magnetocaloric effect(MCE)of LnOF(Ln=Gd,Dy,Ho,and Er)compounds were investigated.Crystallographic study shows that these compounds crystallize in the centrosymmetric space group R3m with an ideal triangular lattice.No long-range magnetic ordering is observed above 2 K for LnOF(Ln=Gd,Ho,and Er).However,DyOF compound undergoes an MPT from paramagnetic(PM)to antiferromagnetic(AFM)at the Neel temperature(TN≈4 K).Considerable reversible MCE is observed in these triangular-lattice compounds.Under the magnetic field change(μ0ΔH)of 0-2 T,the maximum values of magnetic entropy change(-ΔSMmax)of them are 6.1,9.4,12.7,and 14.1 J/(kg·K),respectively.Interestingly,the value of ErOF with Ising-like spin is 2.3 times that of GdOF,which provides an approach for exploring magnetic refrigerants with excellent low-field cryogenic magnetocaloric effect.
文摘In this study, we consider the emergence of explosive synchronization in scale-free networks by considering the Kuramoto model of coupled phase oscillators. The natural frequencies of oscillators are assumed to be correlated with their degrees and frustration is included in the system. This assumption can enhance or delay the explosive transition to synchronization. Interestingly, a de-synchronization phenomenon occurs and the type of phase transition is also changed. Furthermore, we provide an analytical treatment based on a star graph, which resembles that obtained in scale-free networks. Finally, a self-consistent approach is implemented to study the de-synchronization regime. Our findings have important implications for controlling synchronization in complex networks because frustration is a controllable parameter in experiments and a discontinuous abrupt phase transition is always dangerous in engineering in the real world.
文摘Few jobs come without irritations, and foreign language instruction comes with its own particular set of frustrations which, when accumulated, can lead to stress and eventual burnout for teachers.One mechanism for reducing such frustrations is that of emotion regulation, the cognitive and behavioral strategies individuals employ to manage the emotions they experience or display. To date,no known studies have reported specifically on the in-class frustration experienced by language teachers, or on how teachers regulate their feelings of frustration. Herein, the authors discuss the experiences of seven EFL teachers at a university in Japan obtained through a series of semistructured interviews, classroom observations and corresponding stimulated-recall sessions. The authors discuss four salient thematic frustrations: student apathy, classroom silence, misbehavior in the context of relational strain, and working conditions. The results reveal that participants applied contextually-dependent emotion regulation behaviors, the success of which was often contingent on the participants’ levels of confidence and control over the stressors. Thus, participants showed more success in managing pervasive low-level stressors such as apathy and silence, and more support would be welcome to aid them to manage more debilitating stressors such as student misbehavior.The authors offer suggestions for teachers, trainers and institutions on reducing frustration.
基金We thank the National Natural Science Foundation of China(Nos.21925301 and 22103016).
文摘The concept of"packing frustration"has been used to understand the self-assembly behaviors of block copolymers for decades.However,rare attention has been paid to tailoring the packing frustration.This account provides a review of our recent endeavor of controlling the self-assembly of block copolymers via tailoring the packing frustration.The basic idea is to release the packing frustration of chains through the local segregation between different blocks of the same component filing different spaces of near and far.Two different majority blocks are designed to release their packing frustration in the matrix.In particular,this effect of released packing frustration has been successfullycombined with other effectss such as the stretched bridging block to stabilize many unusual low.coordinated phases.We have also proposed to release the packing frustration of minority blocks within the interface curva-ture by designing the architectures of minority blocks.The effect of released packing frustration of minority blocks is aplied to drastically expand the region of spherical phases and thus to obtain significant regions of complex Frank Kasper phases.In brief,the self.assembly of block copolymers can be largely contrlled by tailoring the packing frustration of blocks,even leading to the formation of many unusual ordered phases.
基金supported by the National Natural Science Foundation of China(22302115,22072079)the Fundamental Research Program of Shanxi Province(202303021221056).
文摘Heterogeneous solid frustrated-Lewis-pair(FLP)catalyst is of great promise in practical hydrogenation applications.It has been found that all-solid FLPs can be created on ceria via surface oxygen vacancy regulation.Consequently,it is desired to investigate the mechanisms of the FLP-catalyzed hydrogenation of C=C and C=O and provide insight into the modification of CeO_(2)catalysts for the selective hydrogenation.In this work,the reaction mechanism of the hydrogenation of CH_(2)=CH_(2)and CH_(3)CH=O at the FLP sites constructed on CeO_(2)(110)surface was investigated by density functional theory(DFT),with the classical Lewis acid-base pairs(CLP)site as the reference.The results illustrate that at the CLP site,the dissociated hydride(H^(δ−))forms a stable H−O bond with the surface O atom,while at the FLP site,H^(δ−)is stabilized by Ce,displaying higher activity on the one hand.On the other hand,the electron cloud density of the Ce atom at the FLP site is higher,which can transfer more electrons to the adsorbed C_(C=C)and O_(C=O)atoms,leading to a higher degree of activation for C=C and C=O bonds,as indicated by the Bader charge analysis.Therefore,compared to the CLP site,the FLP site exhibits higher hydrogenation activity for CH_(2)=CH_(2)and CH_(3)CH=O.Furthermore,at the FLP sites,it demonstrates high efficiency in catalyzing the hydrogenation of CH_(2)=CH_(2)with the rate-determining barrier of 1.04 eV,but it shows limited activity for the hydrogenation of CH_(3)CH=O with the rate-determining barrier of 1.94 eV.It means that the selective hydrogenation of C=C can be effectively achieved at the FLP sites concerning selective hydrogenation catalysis.The insights shown in this work help to clarify the reaction mechanism of the hydrogenation of C=C and C=O at FLP site on CeO_(2)(110)and reveal the relationship between the catalytic performance and the nature of the active site,which is of great benefit to development of rational design of heterogeneous FLP catalysts.
文摘The development of solid frustrated Lewis pairs(FLPs)catalysts with porous structures is a promising strategy for advancing green hydrogenation technologies and has garnered significant attention.Leveraging the diverse oxidation states and structural tunability of cerium-based metal-organic frameworks(Ce-MOFs),this study employed a competitive coordination strategy utilizing a single carboxylate functional group ligand to construct a series of MOF-808-X(X=-NH_(2),-OH,-Br,and-NO_(2))featuring rich solid-state FLPs for hydrogenation of unsaturated olefins.The-X functional group serves as a microenvironment,enhancing hydrogenation activity by modulating the electronic properties and acid-base characteristics of the FLP sites.The unique redox properties of elemental cerium facilitate the exposure of unsaturated Ce sites(Ce-CUS,Lewis acid(LA))and adjacent Ce-OH(Lewis base(LB))sites within the MOFs,generating abundant solid-state FLP(Ce-CUS/Ce-OH)sites.Experimental results demonstrate that Ce-CUS and Ce-OH interact with theσandσ^(*)orbitals of H-H,and this"push-pull"synergy promotes heterolytic cleavage of the H-H bond.The lone pair electrons of the electron-donating functional group are transmitted through the molecular backbone to the LB site,thereby increasing its strength and reducing the activation energy required for H_(2)heterolytic cleavage.Notably,at 100℃and 2 MPa H_(2),MOF-808-NH_(2)achieves complete conversion of styrene and dicyclopentadiene,significantly outperforming MOF-808.Based on in-situ analysis and density functional theory calculations,a plausible reaction mechanism is proposed.This research enriches the theoretical framework for unsaturated olefin hydrogenation catalysts and contributes to the development of efficient catalytic systems.
基金supported by the National Natural Science Foundation of China(52162036,52174284 and 22378342)the Key Project of Nature Science Foundation of Xinjiang Province(2021D01D08)the Key Research and Development Program of Hunan Province(2024JK2094).
文摘Long-cycling dendrite-free solid-state lithium metal batteries (LMBs) require fast and uniform lithium-ion (Liþ)transport of solid-state electrolytes (SSEs). However, the SSEs still face the problems of low ionic conductivity, lowLiþ transference number, and unstable interface with lithium metal. In this work, a novel strategy of frustratedLewis pairs (FLPs) modulating solid polymer electrolytes (SPEs) has been firstly proposed that enables durable Lireversible cycling. The tunable strength of Lewis acid and base dual-active sites of nickel borate FLPs can syn-ergisticallypromote both the dissociation of lithium salts and the transfer of Liþ. As a consequence, the FLPsmodulated SPEs (SPE-NiBO-150) exhibit high ionic conductivity of 4.92×10^(-4)S cm^(-1), high Liþ transferencenumber of 0.74, and superior interface compatibility with both lithium anode and LiFePO4 cathode at room-temperature.The Li//SPE-NiBO-150//Li symmetric cell demonstrates ultralong cycle stability (over 10,000 h(417 days) at both current density of 0.2 and 0.5 mA cm〓〓2), and the assembled solid-state LiFePO4//SPE-NiBO-150//Libattery also shows excellent performance (86% capacity retention for 300 cycles at 0.5C). The presentwork supplies a new insight into designing high-performance SPEs for solid-state LMB applications.
文摘One-step direct production of methanol from methane and water(PMMW)under mild conditions is challenging in heterogeneous catalysis owing to the absence of highly effective catalysts.Herein,we designed a series of“Single-Atom”-“Frustrated Lewis Pair”(SA-FLP)dual active sites for the direct PMMW via density functional theory(DFT)calculations combined with a machine learning(ML)approach.The results indicate that the nine designed SA-FLP catalysts are capable of efficiently activate CH4 and H_(2)O and facilitate the coupling of OH^(*)and CH_(3)^(*)into methanol.The DFT-based microkinetic simulation(MKM)results indicate that CH_(3)OH production on Co1-FLP and Pt1-FLP catalysts can reach the turnover frequencies(TOFs)of 1.01×10^(−3)s^(-1)and 8.80×10^(−4)s^(-1),respectively,which exceed the experimentally reported values by three orders of magnitude.ML results unveil that the gradient boosted regression model with 13 simple features could give satisfactory predictions for the TOFs of CH_(3)OH production with RMSE and R^(2)of 0.009 s^(-1)and 1.00,respectively.The ML-predicted MKM results indicate that four catalysts including V_(1-),Fe_(1-),Ti_(1-),and Mn_(1)-FLP exhibit higher TOFs of CH_(3)OH production than the value that the most relevant experiments reported,indicating that the four catalysts are also promising catalysts for the PMMW.This study not only develops a simple and efficient approach for design and screening SA-FLP catalysts but also provides mechanistic insights into the direct PMMW.
基金supports by the National Key Research and Development Program of China (Grant No.2024YFA1409200)the National Natural Science Foundation of China (Grant Nos.12222412 and 12047503)+1 种基金CAS Project for Young Scientists in Basic Research (Grant No.YSBR-057)supports by the National Natural Science Foundation of China (Grant No.12374144)。
文摘We extend a semiclassical numerical method, bosonic auxiliary-field Monte Carlo, to quantum spin systems. This method breaks the lattice into clusters, solves each cluster precisely and couples them with classical auxiliary fields through classical Monte Carlo simulation. We test the method with antiferromagnetic spin models in one-dimensional chains, square lattices and triangular lattices, and obtain reasonable results at finite temperatures. This algorithm builds a bridge between classical Monte Carlo method and quantum methods. The algorithm can be improved with either progress in classical Monte Carlo sampling or the development of quantum solvers, and can also be further applied to systems with different lattices or interactions.
