Effects of Fe solid solute on grain boundaries of bi-crystal Cu: A molecular dynamics simulation

Grain boundaries(GBs)play a crucial role on the structural stability and mechanical properties of Cu and its alloys.In this work,molecular dynamics(MD)simulations are employed to study the effects of Fe solutes on the formation energy,excess volume,dislocations and melting behaviors of GBs in CuFe alloys.It is illustrated that Fe solute affects the structural stability of Cu GBs substantially,the formation energy of GBs is reduced,but the thickness and melting point of GBs are increased,that is,the structural stability of Cu GBs is significantly improved owing to the Fe solutes.A strong scaling law exists between the formation energy,excess volume,thickness and melting point of GBs.Therefore,Fe solid solute plays an important role in the characteristics of GBs in bi-crystal Cu.

Modeling the Interaction between Vacancies and Grain Boundaries during Ductile Fracture

The experimental results in previous studies have indicated that during the ductile fracture of pure metals,vacancies aggregate and form voids at grain boundaries.However,the physical mechanism underlying this phenomenon remains not fully understood.This study derives the equilibrium distribution of vacancies analytically by following thermodynamics and the micromechanics of crystal defects.This derivation suggests that vacancies cluster in regions under hydrostatic compression to minimize the elastic strain energy.Subsequently,a finite element model is developed for examining more general scenarios of interaction between vacancies and grain boundaries.This model is first verified and validated through comparison with some available analytical solutions,demonstrating consistency between finite element simulation results and analytical solutions within a specified numerical accuracy.A systematic numerical study is then conducted to investigate the mechanism that might govern the micromechanical interaction between grain boundaries and the profuse vacancies typically generated during plastic deformation.The simulation results indicate that the reduction in total elastic strain energy can indeed drive vacancies toward grain boundaries,potentially facilitating void nucleation in ductile fracture.

Natural vibration and critical velocity of translating Timoshenko beam with non-homogeneous boundaries

In most practical engineering applications,the translating belt wraps around two fixed wheels.The boundary conditions of the dynamic model are typically specified as simply supported or fixed boundaries.In this paper,non-homogeneous boundaries are introduced by the support wheels.Utilizing the translating belt as the mechanical prototype,the vibration characteristics of translating Timoshenko beam models with nonhomogeneous boundaries are investigated for the first time.The governing equations of Timoshenko beam are deduced by employing the generalized Hamilton's principle.The effects of parameters such as the radius of wheel and the length of belt on vibration characteristics including the equilibrium deformations,critical velocities,natural frequencies,and modes,are numerically calculated and analyzed.The numerical results indicate that the beam experiences deformation characterized by varying curvatures near the wheels.The radii of the wheels play a pivotal role in determining the change in trend of the relative difference between two beam models.Comparing the results unearths that the relative difference in equilibrium deformations between the two beam models is more pronounced with smaller-sized wheels.When the two wheels are of equal size,the critical velocities of both beam models reach their respective minima.In addition,the relative difference in natural frequencies between the two beam models exhibits nonlinear variation and can easily exceed 50%.Furthermore,as the axial velocities increase,the impact of non-homogeneous boundaries on modal shape of translating beam becomes more significant.Although dealing with non-homogeneous boundaries is challenging,beam models with non-homogeneous boundaries are more sensitive to parameters,and the differences between the two types of beams undergo some interesting variations under the influence of non-homogeneous boundaries.

INCOMPRESSIBLE LIMIT OF IDEAL MAGNETOHYDRODYNAMICS IN A DOMAIN WITH BOUNDARIES

We study the incompressible limit of classical solutions to compressible ideal magneto-hydrodynamics in a domain with a flat boundary.The boundary condition is characteristic and the initial data is general.We first establish the uniform existence of classical solutions with respect to the Mach number.Then,we prove that the solutions converge to the solution of the incompressible MHD system.In particular,we obtain a stronger convergence result by using the dispersion of acoustic waves in the half space.

Plasma induced grain boundaries to boost electrochemical reduction of CO_(2)to formate

Bismuth-based catalysts are highly promising for the electrochemical carbon dioxide reduction reaction(eCO_(2)RR)to formate product.However,achieving high activity and selectivity towards formate and ensuring long-term stability remains challenging.This work reports the oxygen plasma inducing strategy to construct the abundant grain boundaries of Bi/BiO_x on ultrathin two-dimensional Bi nanosheets.The oxygen plasma-treated Bi nanosheet(OP-Bi)exhibits over 90%Faradaic efficiency(FE)for formate at a wide potential range from-0.5 to-1.1 V,and maintains a great stability catalytic performance without significant decay over 30 h in flow cell.Moreover,membrane electrode assembly(MEA)device with OPBi as catalyst sustains the robust current density of 100 mA cm^(-2)over 50 h,maintaining a formate FE above 90%.In addition,rechargeable Zn-CO_(2)battery presents the peak power density of1.22 mW cm^(-2)with OP-Bi as bifunctional catalyst.The mechanism experiments demonstrate that the high-density grain boundaries of OP-Bi provide more exposed active sites,faster electron transfer capacity,and the stronger intrinsic activity of Bi atoms.In situ spectroscopy and theo retical calculations further elucidate that the unsaturated Bi coordination atoms between the grain boundaries can effectively activate CO_(2)molecules through elongating the C-O bond,and reducing the formation energy barrier of the key intermediate(^(*)OCOH),thereby enhancing the catalytic performance of eCO_(2)RR to formate product.

Politics of Sexual Violence in Ian McEwan’s The Innocent

This paper examines the role of sexual violence in Ian McEwan’s novel The Innocent and its relationship to the author’s examination of the boundary between the political and the personal. Contextualizing the protagonist Leonard Marnham’s violence against the heat of the geopolitical struggles of the Cold War, this study traces his transformation from an innocent technician to a violent agent of political and sexual aggression, and reads his attempted rape of his German lover, Maria, as a nexus between personal relationships and geopolitical struggles. It highlights how Leonard’s violence is a reflection of and at the same time a product of the postwar political landscape. By drawing on the body politic of sexual violence, it analyzes the feminized representation of Leonard, arguing that Leonard is both a perpetrator as well as a victim of the postwar political struggles. Hence the conclusion that sexual violence is employed by the author as a trope to dramatize the invasion of the political onto the personal, and the novel is a political novel that illustrates how the entanglement of international politics and private life can lead to a profound distortion of personal relationships, where the dynamics of power, dominance, and submission that define the public sphere can seep into and corrupt even the most intimate aspect of human interaction.

Reform Practice of College Students’ Employment Guidance Course under the Concept of Curriculum Ideology and Politics

Under the background of“fostering character and civic virtue,”higher education must effectively integrate ideological and political education.The concept of curriculum ideology and politics has become increasingly developed and sophisticated,which can be a guiding concept for the teaching and reform practice of college students’employment guidance courses.Based on educational observation and logical analysis,this paper elaborates on the connotation of the concept of curriculum ideology and politics,analyzes the key points of the reform of college students’employment guidance courses under this concept,and affirms the value of course reform.On this basis,this paper specifically analyzes the common problems in the reform of the employment guidance course under the new concept and makes a detailed interpretation of the performance problems such as the vague course objectives and the lack of innovation in the course teaching methods.Combined with the relevant problems,this paper proposes strategies such as building the course objective system by linking the curriculum ideology and politics,and driving the teaching innovation of the course from multiple perspectives,aiming to provide more references for the corresponding course reform.

Extensive identification of landslide boundaries using remote sensing images and deep learning method

The frequent occurrence of extreme weather events has rendered numerous landslides to a global natural disaster issue.It is crucial to rapidly and accurately determine the boundaries of landslides for geohazards evaluation and emergency response.Therefore,the Skip Connection DeepLab neural network(SCDnn),a deep learning model based on 770 optical remote sensing images of landslide,is proposed to improve the accuracy of landslide boundary detection.The SCDnn model is optimized for the over-segmentation issue which occurs in conventional deep learning models when there is a significant degree of similarity between topographical geomorphic features.SCDnn exhibits notable improvements in landslide feature extraction and semantic segmentation by combining an enhanced Atrous Spatial Pyramid Convolutional Block(ASPC)with a coding structure that reduces model complexity.The experimental results demonstrate that SCDnn can identify landslide boundaries in 119 images with MIoU values between 0.8and 0.9;while 52 images with MIoU values exceeding 0.9,which exceeds the identification accuracy of existing techniques.This work can offer a novel technique for the automatic extensive identification of landslide boundaries in remote sensing images in addition to establishing the groundwork for future inve stigations and applications in related domains.

Teaching Reform of Basic Medicine Curriculum by Integrating the Perspective of Curriculum Civics and Politics in the Context of Healthy China

Basic medicine is the foundation of basic knowledge of medical science,life science,and natural science,and is the basis for training medical talents.It can help students correctly understand the relationship between disease and health,and is of great significance under the perspective of the Healthy China strategy.However,there are still some deficiencies in the current teaching,and insufficient attention has been paid to civics and politics.Thus,it is necessary to carry out curriculum reform in order to enable students to better understand medical knowledge and master medical skills,to ensure the development of medical education,and to play an important role in basic medicine.This study combines the necessity of curriculum reform under the perspective of civics and politics and puts forward a teaching reform strategy suitable for the development of contemporary medicine to provide a direction for the educational development of basic medicine.

Teaching Reform of Veterinary Microbiology Based on the Hybrid Teaching of Ideology and Politics

The veterinary microbiology teaching team thoroughly implements the national education policy,and iteratively promotes the implementation of the teaching reform of Sanquan education.The teaching team is focused on a“student-centered”approach to education,emphasizing the foundation of“cultivating people and nurturing the root and soul of the nation.”By integrating“knowledge exploration,skill training,and value shaping”into the talent training plan,they are reshaping curriculum objectives and emphasizing ideological education in the syllabus.The teaching content system is being reconstructed,combining multiple interactions of blended teaching with the“six-in-one”ideological education model,to achieve the educational goals of the new agricultural“in-class-extracurricular”approach.This effort provides an empirical basis for the ideological and political teaching reform of the veterinary microbiology curriculum.

Teaching Pathways of Curriculum Civics and Politics in Physical Education Courses of Higher Vocational Colleges and Universities in Chongqing

This paper firstly analyses the due evaluation indexes of curriculum civics and politics in physical education of higher vocational colleges and,based on the indexes,puts forward suggestions to improve the quality of teaching curriculum civics and politics in physical education of higher vocational colleges and universities in Chongqing.It involves maintaining steadfast adherence to professional attributes,unwavering commitment to Sanquan education,and thorough exploration of professional civics and political elements.This approach also entails supplementing extracurricular civics and political resources and utilizing a variety of methods such as contextual teaching and role-modeling to the fullest extent.At the same time,we increase the opportunities for civics and political practice inside and outside the classroom and develop teaching evaluation and assessment in civics and politics.

Exploration of Curriculum Ideology and Politics Integrating Medical Humanities Cultivation Model to Enhance Medical Core Values

Purpose:To explore the application effect of the cultivation mode of Curriculum Ideology and Political Integration of Medical Humanities to enhance the core values of medicine in the clinical internship stage of medical students.Methods:Students in the clinical internship stage of the First Affiliated Hospital of Baotou Medical College were selected,and a total of 156 students in one random class in each grade were taken as the observation group and received the integration cultivation mode;148 students were taken as the control group and employed the traditional mode.The teaching effect of interns in the two groups was analyzed.Results:The teaching performance of students in both groups after clinical internship teaching was improved compared with that before admission;the teaching performance,teaching effect,teaching evaluation,and teaching satisfaction of the observation group were higher than that of the control group.Conclusion:The integration of the medical humanities training model with curriculum ideology and politics in the clinical internship of medical students is conducive to the improvement of teaching performance,teaching evaluation,teaching satisfaction of teachers and students,and the development and improvement of core values of medical students,which is of good value for teaching application.

Research on the Optimization Paths for Outstanding Agricultural Economics and Management Talents under the Background of Curriculum Ideology and Politics

The article aims to discuss how to cultivate outstanding agricultural economics and management talents to meet the needs of agricultural and rural economic development in the new era,within the context of ideological and political education.Through literature review and field research,a series of innovative talent training optimization paths are proposed,and specific suggestions are made for policymakers and educational practitioners.

Research on the Integration Path of Postgraduate Professional Courses into the Construction of Curriculum Ideology and Politics

The curriculum ideology and politics play an important role in cultivating students’correct worldview,outlook on life,and values.In recent years,universities and colleges have begun to pay attention to the cultivation of postgraduates’moral education and the construction of postgraduates’curriculum ideology and politics.This paper takes the course“Theory of Software Engineering”of Anqing Normal University as an example,discusses the paths of integrating postgraduate professional courses into the construction of curriculum ideology and politics,and puts forward the paths of feeding back from scientific research,connecting with practice and summarizing and condensing,which are aimed at improving postgraduates’comprehensive quality and innovation ability,and have positive significance for cultivating high-level applied scientific and technological talents who are both moral and talented.

Exploration of the Integration of Curriculum Ideology and Politics into the Educational Pathway of Standardized Training for General Practice Residents

In recent years,the national higher education reform has proposed the concept of curriculum ideological and political education as a major element.This integration into the standardized training of general practice residents(commonly referred to as general resident training)is an unavoidable trend in the teaching field.Based on the actual situation of our unit at The First Affiliated Hospital of Xi’an Medical University,this paper emphasizes the necessity of incorporating ideological and political education into the general resident training curriculum,despite the absence of pertinent practical experience in how to effectively incorporate such courses into comprehensive residential training.In our hospital,we must assess the ideological and political education in the curriculum of general resident training,proposing a scientific,reasonable ideological and political education concept system for general practice courses,integrating ideological and political education with general practice resident training,and strengthening the team of ideological and political education physicians to teach them to carry out such education,this would foster enthusiasm and initiative.Strengthening admission education and training for general practice resident training,as well as regularly hosting symposiums to share ideas and understand the mission of doctors can provide effective experience for ideological and political education in general resident training courses.

Nano-capillary induced assemble of quantum dots on perovskite grain boundaries for efficient and stable perovskite solar cells

In recent years, perovskite solar cells(PSCs) have propelled into the limelight owing to rapid development of efficiency;however, the abundant defects at the perovskite grain boundaries result in unwanted energy loss and structural degradation. Here, the grain boundaries of perovskite polycrystalline films have been found to act as nanocapillaries for capturing perovskite quantum dots(PQDs), which enable the conformal assemble of PQDs at the top interspace between perovskite grains. The existence of PQDs passivated the surface defects, optimized the interfacial band alignments, and ultimately improved the power conversion efficiency from 19.27% to 22.47% in inverted PSCs. Our findings open up the possibility of selective assembly and structural modulation of the perovskite nanostructures towards efficient and stable PSCs.

An Innovative Study on the Path of Integrating Curriculum Ideology and Politics in College English Teaching:Taking An Overview of Chinese Culture as an Example

With the rapid development of information technology and the Internet,people can easily and quickly obtain news and information from all over the world.As the state’s requirements for the curriculum ideology and politics are being strengthened,it is necessary to adapt to the needs of the times and integrate ideology and politics into college English teaching.Integration of ideology and politics into teaching is a challenge faced by colleges and universities nowadays,which aims to make ideology and politics alive and well and more acceptable to contemporary college students.In view of this,this paper starts with the importance of the integration of ideology and politics into college English teaching,takes An Overview of Chinese Culture as an example,analyzes new approaches for integrating ideology and politics into the teaching process,and formulates the teaching design centered around these approaches,so as to promote the organic integration of ideology and politics with English teaching.

Spatial Control of Lithium Deposition by Controlling the Lithiophilicity with Copper(Ⅰ)Oxide Boundaries

Spatial control of lithium deposition is the most important issue in lithium-metal batteries because of the considerable control of lithium dendrite suppression via the uniform distribution of Li^(+)flux.Although seed materials are crucial for the behavior of lithium deposition,in-depth studies on their physical and chemical control have not been conducted.Here,we describe a new design of seed structure comprising a wrinkled Cu/graphene substrate surrounded by copper(Ⅰ)oxide(Cu_(2)O)on a graphene grain boundary over a large area,which is fabricated by the oxidation of the Cu surface via graphene boundary defects by using chemical vapor deposition(CVD).Scanning and transmission electron microscopy results reveal that Cu_(2)O on the graphene boundary can render a preferential reaction with lithium during the first deposition and assist in the uniform deposition of lithium by preventing the agglomeration of lithium clusters during the second deposition.This two-step process is attributed to the degree of selectivity due to the difference in lithium affinity,which allows long-term electrochemical stability and a high rate capability via boundary effects.This study highlights the significance of the boundary effect,which can open new avenues for the formation of a large family of seed structures in lithium-metal batteries.

Formation mechanism of co-axial grain boundaries in a Mg alloy

Due to the insufficient slip systems in hexagonal close-packed structure,twinning is frequently activated to support stable plastic deformation of Mg alloy.In this work,we found four typical twin-like interfaces with misorientations of 102°,109°,142°and 149°,respectively,which had not only a shared[1120]zone axis of neighboring grains,but also overlapped diffraction spots similar to twins.However,highresolution transmission electron microscope(HRTEM)analysis revealed that the interfaces in real space deviated from the supposed twinning planes in reciprocal space,i.e.their overlapped diffraction spots.We clarified that the incoherent interfaces were co-axial grain boundaries(CGBs).Additionally,a special angle ofθ,close to 90°,between the interface and one side of basal plane,was frequently formed in CGBs.We proposed that interaction of multiple twinning contributes to the formation of CGBs,and theθis formed due to alternative tensile and compression twinning under a uniaxial loading.

CONSTANT DISTANCE BOUNDARIES OF THE t-QUASICIRCLE AND THE KOCH SNOWFLAKE CURVE

LetΓbe a Jordan curve in the complex plane and let Γ_(λ) be the constant distance boundary ofΓ.Vellis and Wu[10]introduced the notion of a(ζ,r_(0))-chordal property which guarantees that,whenλis not too large, Γ_(λ) is a Jordan curve whenζ=1/2 and Γ_(λ) is a quasicircle when 0<ζ<1/2.We introduce the(ζ,r_(0),t)-chordal property,which generalizes the(ζ,r_(0))-chordal property,and we show that under the condition thatΓis(ζ,r_(0),√t)-chordal with 0<ζ<r_(0)^(1−√t)/2,there existsε>0 such that Γ_(λ) is a t-quasicircle once Γ_(λ) is a Jordan curve when 0<λ<ε.In the last part of this paper,we provide an example:Γis a kind of Koch snowflake curve which does not have the(ζ,r_(0))-chordal property for any 0<ζ<1/2,however Γ_(λ) is a Jordan curve whenλis small enough.Meanwhile,Γhas the(ζ,r_(0),√t)-chordal property with 0<ζ<r_(0)^(1−√t)/2 for any t∈(0,1/4).As a corollary of our main theorem, Γ_(λ) is a t-quasicircle for all 0<t<1/4 whenλis small enough.This means that our(ζ,r_(0),t)-chordal property is more general and applicable to more complicated curves.