Nontrivial Topological Phases in Ternary Borides M_(2)XB_(2)(M=W,Mo;X=Co,Ni)

The nontrivial band topologies protected by certain symmetries have attracted significant interest in condensed matter physics.The discoveries of nontrivial topological phases in real materials provide a series of archetype materials to further explore the topological physics.

Mechanism in Solidification of a Ternary Nickel Based Alloy

The experiment employed the use of melt purification and cyclic superheating technique to achieve maximum undercooling of Ni65Cu31Co4 alloy at 300K.Simultaneously,high-speed photography techniques were used to capture the process of alloy liquid phase interface migration,and analyzed the relationship between the shape characteristics of the front end of alloy solidification and undercooling.The microstructure of the alloy was observed through metallographic microscopy,and the micro-morphological characteristics and evolution of the rapidly solidified microstructure were systematically studied.It is found that the grain refinement mechanism of Ni-Cu-Co ternary alloy is similar to that of Ni-Cu binary alloy.Grain refinement at low undercooling is caused by intense dendritic remelting,while grain refinement at high undercooling is attributed to recrystallization,driven by the stress and plastic strain accumulated from the interaction of liquid flow and primary dendrites caused by rapid solidification.It also shows that the addition of the third element Co plays a significant role in solidification rate and re-ignition effect.

Precision tuning of highly efficient Pt-based ternary alloys on nitrogen-doped multi-wall carbon nanotubes for methanol oxidation reaction

The electrochemical methanol oxidation is a crucial reaction in the conversion of renewable energy.To enable the widespread adoption of direct methanol fuel cells(DMFCs),it is essential to create and engineer catalysts that are both highly effective and robust for conducting the methanol oxidation reaction(MOR).In this work,trimetallic PtCoRu electrocatalysts on nitrogen-doped carbon and multi-wall carbon nanotubes(PtCoRu@NC/MWCNTs)were prepared through a two-pot synthetic strategy.The acceleration of CO oxidation to CO_(2) and the blocking of CO reduction on adjacent Pt active sites were attributed to the crucial role played by cobalt atoms in the as-prepared electrocatalysts.The precise control of Co atoms loading was achieved through precursor stoichiometry.Various physicochemical techniques were employed to analyze the morphology,element composition,and electronic state of the catalyst.Electrochemical investigations and theoretical calculations confirmed that the Pt_(1)Co_(3)Ru_(1)@NC/MWCNTs exhibit excellent electrocatalytic performance and durability for the process of MOR.The enhanced MOR activity can be attributed to the synergistic effect between the multiple elements resulting from precisely controlled Co loading content on surface of the electrocatalyst,which facilitates efficient charge transfer.This interaction between the multiple components also modifies the electronic structures of active sites,thereby promoting the conversion of intermediates and accelerating the MOR process.Thus,achieving precise control over Co loading in PtCoRu@NC/MWCNTs would enable the development of high-performance catalysts for DMFCs.

π-Extended giant dimeric acceptor as a third component enables highly efficient ternary organic solar cells with efficiency over 19.2%

Ternary strategy with a suitable third component is a successful strategy to improve the photovoltaic performance of organic solar cells(OSCs).Very recently,Y-series based giant molecule acceptors or oligomerized acceptors have emerged as promising materials for achieving highly efficient and stable binary OSCs,while application as third component for ternary OSCs is limited.Here a novelπ-extended giant dimeric acceptor,GDF,is developed based on central Y series core fusion and rigid BDT as linker,and then incorporated into the state-of-the-art PM1:PC6 system to construct ternary OSCs.The GDF has a near planar backbone,resulting in increasedπ-conjugation,excellent crystallinity,and good electron transport capacity.When GDF is introduced into the PM1:PC6 system,it ensues in a cascade like the lowest unoccupied molecular orbitals(LUMO)energy level alignment,a complementary absorption band with PM1 and PC6,higher and balanced hole and electron mobility,slightly smaller domain size,and a higher exciton dissociation probability for PM1:PC6:GDF(1:1.1:0.1)blend film.As a consequence,the PM1:PC6:GDF(1:1.1:0.1)ternary OSC achieves a champion PCE of 19.22%,with a significantly higher open-circuit voltage and short-circuit current density,compared to 18.45%for the PM1:PC6(1:1.2)binary OSC.Our findings show that employing aπ-extended giant dimeric acceptor as a third component significantly improves the photovoltaic performance of ternary OSCs.

Reconfigurable mechanism-based metamaterials for ternary-coded elastic wave polarizers and programmable refraction control

Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic waves.However,most of them rely on the resonant structural components,and thus are frequency-dependent and unchangeable.Here,we present a reconfigurable 2D mechanism-based metamaterial which possesses transformable and frequency-independent elastic properties.Based on the proposed mechanism-based metamaterial,interesting functionalities,such as ternarycoded elastic wave polarizer and programmable refraction,are demonstrated.Particularly,unique ternary-coded polarizers,with 1-trit polarization filtering and 2-trit polarization separating of longitudinal and transverse waves,are first achieved.Then,the strong anisotropy of the proposed metamaterial is harnessed to realize positive-negative bi-refraction,only-positive refraction,and only-negative refraction.Finally,the wave functions with detailed microstructures are numerically verified.

Recent Advances in Interface Modification of Cu/graphite Composites and Layered Ternary Carbides of Modified Layer Candidate

We review the fundamental properties and significant issues related to Cu/graphite composites.In particular,recent research on the interfacial modification of Cu/graphite composites is addressed,including the metal-modified layer,carbide-modified layer,and combined modified layer.Additionally,we propose the use of ternary layered carbide as an interface modification layer for Cu/graphite composites.

Research on Preparation and Electrochemical Performance of the High Compacted Density Ni-Co-Mn Ternary Cathode Materials

The high compacted density LiNi0.5-xCo0.2Mn0.3MgxO2 cathode material for lithium-ion batteries was synthesized by high temperature solid-state method, taking the Mg element as a doping element and the spherical Ni0.5Co0.2Mn0.3 (OH)2, Li2CO3 as raw materials. The effects of calcination temperature on the structure and properties of the products were investigated. The structure and morphology of cathode materials powder were analyzed by X-ray diffraction spectroscopy (XRD) and scanning electronmicroscopy (SEM). The electrochemical properties of the cathode materials were studied by charge-discharge test and cyclic properties test. The results show that LiNi0.4985Co0.2Mn0.3 Mg0.0015O2 cathode material prepared at calcination temperature 930°C has a good layered structure, and the compacted density of the electrode sheet is above 3.68 g/cm3. The discharge capacity retention rate is more than 97.5% after 100 cycles at a charge-discharge rate of 1C, displaying a good cyclic performance.

Recent progress in ternary mixed matrix membranes for CO_(2) separation

Mixed matrix membranes(MMMs)could combine the advantages of both polymeric membranes and porousfillers,making them an effective alternative to conventional polymer membranes.However,interfacial incompatibility issues,such as the presence of interfacial voids,hardening of polymer chains,and blockage of micropores by polymers between common MMMsfillers and the polymer matrix,currently limit the gas sep-aration performance of MMMs.Ternary phase MMMs(consisting of afiller,an additive,and a matrix)made by adding a third compound,usually functionalized additives,can overcome the structural problems of binary phase MMMs and positively impact membrane separation performance.This review introduces the structure and fabrication processes for ternary MMMs,categorizes various nanofillers and the third component,and summarizes and analyzes in detail the CO_(2) separation performance of newly developed ternary MMMs based on both rubbery and glassy polymers.Based on this separation data,the challenges of ternary MMMs are also discussed.Finally,future directions for ternary MMMs are proposed.

Alkyl chain modulation of asymmetric hexacyclic fused acceptor synergistically with wide bandgap third component for high efficiency ternary organic solar cells

Herein,two asymmetric hexacyclic fused small molecule acceptors(SMAs),namely BP4F-HU and BP4F-UU,were synthesized.The elongated outside chains in the BP4F-UU molecule played a crucial role in optimizing the morphology of blend film,thereby improving charge mobility and reducing energy loss within the corresponding film.Notably,the PM6:BP4F-UU device exhibited a higher open-circuit voltage(V_(oc))of 0.878 V compared to the PM6:BP4F-HU device with a V_(oc)of 0.863 V.Further,a new wide bandgap SMA named BTP-TA was designed and synthesized as the third component to the PM6:BP4F-UU host binary devices,which showed an ideal complementary absorption spectrum in PM6:BP4F-UU system.In addition,BTP-TA can achieve efficient intermolecular energy transfer to BP4F-UU by fluorescence resonance energy transfer(FRET)pathway,due to the good overlap between the photoluminescence(PL)spectrum of BTP-TA and the absorption region of BP4F-UU.Consequently,ternary devices with 15wt%BTP-TA exhibits broader photon utilization,optimal blend morphology,and reduced charge recombination compared to the corresponding binary devices.Consequently,PM6:BP4F-UU:BTP-TA ternary device achieved an optimal power conversion efficiency(PCE)of 17.83%with simultaneously increased V_(oc)of 0.905 V,short-circuit current density(J_(sc))of 26.14 mA/cm^(2),and fill factor(FF)of 75.38%.

基于TCAM模型的初高中衔接教育课堂探究——以初高中物理“共点力平衡”知识点衔接为例

核心素养立意下的课程改革,关注学生素养全程贯通培养,衔接教育为学生的健康成长提供了无缝链接。学校体制建设、教师课堂教学、初中学生学业健康成长对衔接教育的课堂提出了现实需要。从分析课标、研究教材入手,发现断层断面,捕捉初高中教学内容衔接点,实施嵌入式TCAM课堂范式,在初中课堂开展拓展性衔接,在高中课堂实施引接性衔接。在衔接教育的过程中,从创新真实情境衔接问题入手,充分发挥小组合作探究,迁移应用并能够初步建立模型,实现学生素养的贯通成长。

Study of the Viscosity and Specific Gravity of the Ternary Used Frying Oil (UFO)-Bioethanol-Diesel System

Fossil fuels cover around 80% of global energy consumption. However, the problems linked to their use justify the choice of using biofuel. In order to reduce as much as possible, diesel rate, an increase in the number of additives may be considered. Thus, in this work, the study of the used frying oil (UFO), bioethanol and diesel ternary system was undertaken. It emerges from this study that the addition of bioethanol reduces the viscosity and the density of the ternary system and permits a 90% substitution rate for diesel between the UFO and bioethanol. Finally, the percentage of oil becomes 40% after adding alcohol compared to the binary diesel crude vegetable oil mixture where this rate is 30%.

Highly Aligned Ternary Nanofiber Matrices Loaded with MXene Expedite Regeneration of Volumetric Muscle Loss

Current therapeutic approaches for volumetric muscle loss(VML)face challenges due to limited graft availability and insufficient bioactivities.To overcome these limitations,tissue-engineered scaffolds have emerged as a promising alternative.In this study,we developed aligned ternary nanofibrous matrices comprised of poly(lactide-co-ε-caprolactone)integrated with collagen and Ti_(3)C_(2)T_(x)MXene nanoparticles(NPs)(PCM matrices),and explored their myogenic potential for skeletal muscle tissue regeneration.The PCM matrices demonstrated favorable physicochemical properties,including structural uniformity,alignment,microporosity,and hydrophilicity.In vitro assays revealed that the PCM matrices promoted cellular behaviors and myogenic differentiation of C2C12 myoblasts.Moreover,in vivo experiments demonstrated enhanced muscle remodeling and recovery in mice treated with PCM matrices following VML injury.Mechanistic insights from next-generation sequencing revealed that MXene NPs facilitated protein and ion availability within PCM matrices,leading to elevated intracellular Ca^(2+)levels in myoblasts through the activation of inducible nitric oxide synthase(i NOS)and serum/glucocorticoid regulated kinase 1(SGK1),ultimately promoting myogenic differentiation via the m TOR-AKT pathway.Additionally,upregulated i NOS and increased NO–contributed to myoblast proliferation and fiber fusion,thereby facilitating overall myoblast maturation.These findings underscore the potential of MXene NPs loaded within highly aligned matrices as therapeutic agents to promote skeletal muscle tissue recovery.

First-Principles Study of the New Layered Ternary Metal Telluride,Eu_(2)InTe_(5)

In this study,we performed first-principles calculations using the VASP(Vienna Ab initio Simulation)software package to investigate the crystal structure,electronic structure,and optical properties of a new layered ternary metal chalcogenide,Eu_(2)InTe_(5).Our results show that Eu_(2)InTe_(5) is a non-zero-gap metal with a layered structure characterized by strong intra-layer atomic bonding and weak inter-layer interaction,which suggests its potential application as a nanomaterial.We also studied the optical properties,including the absorption coefficient,imaginary and real parts of the complex dielectric constant,and found that Eu_(2)InTe_(5) exhibits strong photoresponse characteristics at the junction of ultraviolet and visible light as well as blue-green light,with peaks at wavelengths of 389 nm and 477 nm.This suggests that it could be used in the development of UV(ultraviolet)detectors and other optoelectronic devices.Furthermore,due to its strong absorption,low loss,and low reflectivity,Eu_(2)InTe_(5) has the potential to be used as a promising photovoltaic absorption layer in solar cells.

Comparative investigations of ternary thermite Al/Fe_(2)O_(3)/CuO and Al/Fe_(2)O_(3)/Bi_(2)O_(3) from pyrolytic,kinetics and combustion behaviors

To develop new energy enhancement energetic materials with great combustion performance and thermal stability,two kinds of ternary thermite,Al/Fe_(2)O_(3)/CuO and Al/Fe_(2)O_(3)/Bi_(2)O_(3),were prepared and analyzed via mechanical ball milling.The samples were characterized by SEM,XRD,TG-DSC,constant volume and constant pressure combustion experiments.The first exothermic peaks of Al/Fe_(2)O_(3)/CuO and Al/Fe_(2)O_(3)/Bi_(2)O_(3) appear at 579°C and 564.5°C,respectively.The corresponding activation energies are similar.The corresponding mechanism functions are set as G(a) = [-ln(1-a)]^(3/4) and G(a) =[-ln(1-a)]2/3,respectively,which belong to the Avrami-Erofeev equation.Al/Fe_(2)O_(3)/CuO has better thermal safety.For small dose samples,its critical temperature of thermal explosion is 121.05°C higher than that of Al/Fe_(2)O_(3)/Bi_(2)O_(3).During combustion,the flame of Al/Fe_(2)O_(3)/CuO is spherical,and the main products are FeAl_(2)O_(4) and Cu.The flame of Al/Fe_(2)O_(3)/Bi_(2)O_(3)is jet-like,and the main products are Al_(2)O_(3),Bi and Fe.Al/Fe_(2)O_(3)/Bi_(2)O_(3)has better ignition and gas production performance.Its average ignition energy is 4.2 J lower than that of Al/Fe_(2)O_(3)/CuO.Its average step-up rate is 28.29 MPa/s,which is much higher than 6.84 MPa/s of Al/Fe_(2)O_(3)/CuO.This paper provides a reference for studying the thermal safety and combustion performance of ternary thermite.

A comparative study on Sn macrosegregation behavior of ternary Al-Sn-Cu alloys prepared by gravity casting and squeeze casting

A comprehensive study on Sn macrosegregation behavior in ternary Al-Sn-Cu alloys was carried out by comparative analysis between gravity casting and squeeze casting samples.The microstructure and Sn distribution of the castings were characterized by metallography,scanning electron microscopy(SEM),energy-dispersive X-ray(EDX)spectroscopy,and a direct reading spectrometer.Results show that there are obvious differences in Sn morphology between gravity casting and squeeze casting alloys.Under squeeze casting condition,the grain size of the casting is smaller and the distribution ofβ(Sn)is uniform.This effectively reduces the segregation of triangular grain boundary as well as the segregation of Sn.The segregation types of Sn in gravity casting and squeeze casting samples are obviously different.The upper surfaces of gravity casting samples show severe negative segregation,while all the lower surfaces have positive segregation.Compared with gravity casting,squeeze casting solidifies under isostatic pressure.Due to the direct contact between the upper surface of the casting and the mold,the casting solidifies faster under higher undercooling degree and pressure.Consequently,the uniform distribution of Sn reduces the segregation phenomenon on the surface of the casting.

Efficient, continuous oxidation of durene to pyromellitic dianhydride mediated by a V-Ti-P ternary catalyst: The remarkable doping effect

Continuous preparation of pyromellitic dianhydride(PMDA) from durene has been studied using a fixedbed reactor. The reaction was performed using a phosphorus-vanadium-titanium ternary catalyst.Relatively high selectivity and yield of PMDA was obtained. The in-situ characterization was combined with theoretical calculation to reveal the reaction mechanisms, and the remarkable doping effect was discussed.

Incorporation ofκ-carrageenan improves the practical features of agar/konjac glucomannan/κ-carrageenan ternary system

Three materials(agar,konjac glucomannan(KGM)andκ-carrageenan)were used to prepare ternary systems,i.e.,sol-gels and their dried composites conditioned at varied relative humidity(RH)(33%,54%and 75%).Combined methods,e.g.,scanning electron microscopy,small-angle X-ray scattering,infrared spectroscopy(IR)and X-ray diffraction(XRD),were used to disclose howκ-carrageenan addition tailors the features of agar/KGM/κ-carrageenan ternary system.As affirmed by IR and XRD,the ternary systems withκ-carrageenan below 25%(agar/KGM/carrageenan,50:25:25,m/m)displayed proper component interactions,which increased the sol-gel transition temperature and the hardness of obtained gels.For instance,the ternary composites could show hardness about 3 to 4 times higher than that for binary counterpart.These gels were dehydrated to acquire ternary composites.Compared to agar/KGM composite,the ternary composites showed fewer crystallites and nanoscale orders,and newly-formed nanoscale structures from chain assembly.Such multi-scale structures,for composites withκ-carrageenan below 25%,showed weaker changes with RH,as revealed by especially morphologic and crystalline features.Consequently,the ternary composites with lessκ-carrageenan(below 25%)exhibited stabilized elongation at break and hydrophilicity at different RHs.This hints to us that agar/KGM/κ-carrageenan composite systems can display series applications with improved features,e.g.,increased sol-gel transition point.

Elucidating the promotion mechanism of the ternary cooperative heterostructure toward industrial-level urea oxidation catalysis

From the perspective of electronic structure modulation,it is highly desirable to rationally design the active urea oxidation reaction(UOR)catalysts through interface engineering.The binary cooperative heterostructure systems have been shown significant enhancement for catalyzing UOR,but their performance still remains unsatisfactory for industrialization because of the unfavorable intermediate adsorption/desorption and deficient electron transfer channels.In response,taking the ternary cooperative Ni_5P_(4)/NiSe_(2)/Ni_(3)Se_(4) heterostructure as the proof-of-concept paradigm,a catalytic model is rationally put forward to elucidate the UOR promotion mechanism at the molecular level.The rod-like Ni_5P_(4)/NiSe_(2)/Ni_(3)Se_(4) nanoarrays with three-phase heterojunction are experimentally fabricated on Ni foam(named as Ni_5P_(4)/NiSe_(2)/Ni_(3)Se_(4)/NF)via simple two-step processes.The density functional theory calculations disclose that construction of Ni_5P_(4)/NiSe_(2)/Ni_(3)Se_(4) heterostructure model not only induce charge redistribution at the interfacial region for creating innumerable electron transfer channels,but also endow it with a moderate d-band center that could help to build a balance between adsorption and desorption of diverse UOR intermediates.Benefiting from the unique rod-like nanoarrays with large specific surface area and the optimized electronic structure,the well-designed Ni_5P_(4)/NiSe_(2)/Ni_(3)Se_(4)/NF could act as a robust catalyst for driving UOR at industrial-level current densities under tough environments,offering great potential for commercial applications.

PtCoNi ternary intermetallic compounds anchored on Co,Ni and N co-doped mesoporous carbon:Synergetic effect between PtCoNi nanoparticles and doped mesoporous carbon promotes the catalytic activity

Highly active and robust electrocatalysts are desired for proton exchange membrane fuel cells.Pt-based intermetallic compounds(IMCs) have been recognized as one of the most promising low-platinum catalysts for fuel cells(FCs).Herein,we report a high-performance IMCs by anchoring ordered PtCoNi ternary nanoparticles on the N,Co and Ni co-doped dodecahedral mesoporous carbon(DMC).While the introduced Co and Ni participate in the formation of PtCoNi IMCs,some of them are doped in the mesoporous carbon and coordinated by N to form Co-N_(y)/Ni-N_(z)dual active centers,which further enhances the electrocatalytic activity towards oxygen reduction reaction.Moreover,the addition of Ni results in a negative shift of the d-band center of Pt as compared to the Pt/DMC and Pt_(3)Co/DMC,making it easier to adsorb oxygen on the surface.As expected,our optimal sample Pt_(3)Co_(0.7)Ni_(0.3)/DMC exhibits excellent performance with mass activity and specific activity of 1.32 A mgPt-1and 1.98 mA cm^(-2)at 0.9 V,which are 7.33and 6.19 times that of commercial Pt/C,respectively.The Pt_(3)Co_(0.7)Ni_(0.3)/DMC also reveals much better cathodic performance in an H2-air single fuel cell than commercial Pt/C catalyst with a power density of0.802 W cm^(-2).This work provides critical sights into constructing efficient catalysts by ternary intermetallic strategy and synergetic effect between active components and support.

Highly efficient organic solar cells with improved stability enabled by ternary copolymers with antioxidant side chains

The stability of organic solar cells(OSCs)remains a major concern for their ultimate industrialization due to the photo,oxygen,and water susceptibility of organic photoactive materials.Usually,antioxidant additives are blended as radical scavengers into the active layer.However,it will induce the intrinsic morphology instability and adversely affect the efficiency and long-term stability.Herein,the antioxidant dibutylhydroxytoluene(BHT)group has been covalently linked onto the side chain of benzothiadiazole(BT)unit,and a series of ternary copolymers D18-Cl-BTBHTx(x=0,0.05,0.1,0.2)with varied ratio of BHT-containing side chains have been synthesized.It was found that the introduction of BHT side chains would have a negligible effect on the photophysical properties and electronic levels,and the D18-Cl-BTBHT0.05:Y6-based OSC achieved the highest power conversion efficiency(PCE)of 17.6%,which is higher than those based active layer blended with BHT additives.More importantly,the unencapsulated device based on D18-Cl-BTBHTx(x=0.05,0.1,0.2)retained approximately 50%of the initial PCE over 30 hours operation under ambient conditions,significantly outperforming the control device based on D18-Cl(90%degradation in PCE after 30 h).This work provides a new structural design strategy of copolymers for OSCs with simultaneously improved efficiency and stability.