The topological states of the two-leg and three-leg ladders formed by two trivial quantum wires with different lattice constants are theoretically investigated. Firstly, we take two trivial quantum wires with a lattic...
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The topological states of the two-leg and three-leg ladders formed by two trivial quantum wires with different lattice constants are theoretically investigated. Firstly, we take two trivial quantum wires with a lattice constant ratio of 1:2 as an example. For the symmetric nearest-neighbor intra-chain hopping two-leg ladder, the inversion symmetry protected topological insulator phase with two degenerate topological edge states appears. When the inversion symmetry is broken, the topological insulators with one or two topological edge states of different energies and topological metals with edge states embedded in the bulk states could emerge depending on the filling factor. The topological origin of these topological states in the two-leg ladders is the topological properties of the Chern insulators and Chern metals. According to the arrangement of two trivial quantum wires, we construct two types of three-leg ladders. Each type of the three-leg ladder could be divided into one trivial subspace and one topological nontrivial subspace by unitary transformation. The topological nontrivial subspace corresponds to the effective two-leg ladder model. As the filling factor changes, the system could be in topological insulators or topological metals phases. When the two-leg ladder is constructed by two trivial quantum wires with a lattice constant ratio of 1:3 and 2:3, the system could also realize rich topological states such as the topological insulators and topological metals with the topological edge states. These rich topological states in the two-leg and three-leg ladders could be confirmed by current experimental techniques.
Au hierarchical architectures with special morphology and structures are strongly desired in varied ***,a simple synthesis method was developed for the one-step preparation of Au micronails(MNs)at the planar liquid-li...
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Au hierarchical architectures with special morphology and structures are strongly desired in varied ***,a simple synthesis method was developed for the one-step preparation of Au micronails(MNs)at the planar liquid-liquid interface under mild *** well-defined Au MNs were grown and constructed at CHCl_(3)-H_(2)O interface at room temperature using aniline in CHCl_(3)as reducing agent and HAuCl_(4)in H_(2)O as precursor and no surfactant or seed is *** intriguing Au MNs with rough surface consist of big heads and thin rods,just like iron nails in ***,through simple changing the reagent concentrations,the length and surface roughness of Au MNs can be adjusted *** effects of a series of factors on the morphology and structure of the products are studied in *** p-aminothiophenol as a molecular probe,the as-obtained Au MNs all exhibit dramatically improved surface enhanced Raman scattering sensitivity and high reproducibility,the enhancement factor and limit of detection of Au MNs are 5.4×10^(5)and 1.0×10^(-10),respectively.
The catalytic efficacy of copper-based catalysts for volatile organic compounds(VOCs) oxidation is significantly affected by the metal oxide support's chemical properties. However, rigorous comparative analyses ...
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The catalytic efficacy of copper-based catalysts for volatile organic compounds(VOCs) oxidation is significantly affected by the metal oxide support's chemical properties. However, rigorous comparative analyses on TiO2and CeO2supports are scarce. This study systematically constructs Cu/TiO2and Cu/CeO2catalysts and investigates their mechanisms in promoting propane oxidation. Cu/CeO2exhibits superior performance and stability. Our research reveals the key role of Cu-O-Ce interfacial architecture in forming Cu1+sites for efficient propane adsorption and triggering surface Olattgeneration, accelerating propane combustion. These findings elucidate Cu/CeO2catalyst enhanced performance and offer insights into non-noble metal catalysts. By demonstrating CeO2catalyst superiority, this study provides a basis for selecting optimal support materials to optimize catalyst performance, driving the development of cost-effective and eco-friendly catalytic technologies for air pollution control.
The logical blocking of finite state machines(FSMs) is examined at the three levels of formulation,detection, and search from an STP viewpoint(semi-tensor product of matrices). The research idea regards an FSM as a lo...
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The logical blocking of finite state machines(FSMs) is examined at the three levels of formulation,detection, and search from an STP viewpoint(semi-tensor product of matrices). The research idea regards an FSM as a logical system. The realizing method treats the event sequence exciting an FSM as the input signal of a logical system and treats the current states of an FSM as the states of a logical system. Based on a recently developed bilinear dynamic model of FSMs, a difference equation-like model is first proposed to describe the logical blocking. By defining a loop structure of FSMs and using the difference equation-like model, a criterion is built by which whether a given FSM is blocking can be easily judged. If it is, several algorithms are designed to find all the logical blocking of the FSM. Further, these results are extended to apply to the case of nondeterministic FSMs and, thus, to networks of FSMs. The proposed STP approach may provide a new angle for considering the problems of FSMs, and the presented results may strengthen the links between systems governed by human-designed rules and systems governed by natural laws.
Material composition and structural design are important factors influencing the electromagnetic wave(EMW)absorption performance of *** alleviate the impedance mismatch attributed to the high dielectric constant of Ti...
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Material composition and structural design are important factors influencing the electromagnetic wave(EMW)absorption performance of *** alleviate the impedance mismatch attributed to the high dielectric constant of Ti_(3)C_(2)T_(x)MXene,we have successfully synthesized core‐shell structured SiO_(2)@MXene@MoS_(2)*** architecture,comprising SiO_(2) as the core,MXene as the intermediate layer,and MoS_(2) as the outer shell,is achieved through an electrostatic self‐assembly method combined with a hydrothermal *** complex core‐shell structure not only provides a variety of loss mechanisms that effectively dissipate electromagnetic energy but also prevents self‐aggregation of MXene and MoS_(2) ***,the synergistic combination of SiO_(2) and MoS_(2) with highly conductive MXene enables the suitable dielectric constant of the composites,ensuring optimal impedance ***,the core‐shell structured SiO_(2)@MXene@MoS_(2) nanospheres exhibit excellent EMW absorption performance,featuring a remarkable minimum reflection loss(RL_(min))of−52.11 dB(2.4 mm).It is noteworthy that these nanospheres achieve an ultra‐wide effective absorption bandwidth(EAB)of 6.72 *** work provides a novel approach for designing and synthesizing high‐performance EMW absorbers characterized by“wide bandwidth and strong reflection loss.”
To understand the hot compression deformation characteristics of the self-developed Al-9.3Zn-2.4Mg^(-1).1Cu alloy,the hot compression tests of Al-9.3Zn-2.4Mg^(-1).1Cu alloy were investigated by Gleeble 1500 thermo-mec...
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To understand the hot compression deformation characteristics of the self-developed Al-9.3Zn-2.4Mg^(-1).1Cu alloy,the hot compression tests of Al-9.3Zn-2.4Mg^(-1).1Cu alloy were investigated by Gleeble 1500 thermo-mechanical simulator to determine the best hot processing *** hot deformation temperatures were 300,350,400,and 450℃,and the strain rates were 1,0.1,0.01,and 0.003 s^(-1),*** on the experimental results,the constitutive equation and hot processing maps are established,and the corresponding strain rate and temperature-sensitive index are *** results show that Al-9.3Zn-2.4Mg^(-1).1Cu alloy has a dynamic softening trend and high strain rate sensitivity during the isothermal compression *** hot deformation behavior can be described by an Arrhenius-type equation after strain *** temperature has a negligible effect on the hot processing properties,while a low strain rate is favorable for the hot working of *** processing maps and microstructure show that the optimal processing conditions were in the temperature range of 400-450℃and strain rate range of 0.003-0.005 s^(-1).
Active hydro-pneumatic suspension has been widely used in heavy vehicles for its extraordinary merits, such as non-linear stiffness and damping, adjustable body height, etc. This paper proposes a vehicle height contro...
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In this work,flexible photothermal PVA/Ti_(2)O_(3) composite films with different amount(0 wt%,5 wt%,10 wt%,15 wt%)of Ti_(2)O_(3) particles modified by steric acid were prepared by a simple solution casting *** micros...
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In this work,flexible photothermal PVA/Ti_(2)O_(3) composite films with different amount(0 wt%,5 wt%,10 wt%,15 wt%)of Ti_(2)O_(3) particles modified by steric acid were prepared by a simple solution casting *** microstructures,XRD patterns,FTIR spectra,UV-Vis-NIR spectra thermo-conductivity,thermo-stability and photothermal effects of these composite films were all *** results indicated that Ti_(2)O_(3) particles were well dispersed throughout the polyvinyl alcohol(PVA)matrix in the PVA/Ti_(2)O_(3) composite *** Ti_(2)O_(3) particles could also effectively improve the photothermal properties of the composite films which exhibited high light absorption and generated a high temperature(about 57.4℃for film with 15 wt%Ti_(2)O_(3) amount)on the surface when it was irradiated by a simulated sunlight source(1 kW/m^(2)).
Chemodivergent synthesis of benzofurans and 2,3-dihydrobenzofurans has been *** a reaction system consisting of DBDMH and K_(2)CO_(3) as promotors,controlled conditions enabled the formation of two sets of valuable he...
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Chemodivergent synthesis of benzofurans and 2,3-dihydrobenzofurans has been *** a reaction system consisting of DBDMH and K_(2)CO_(3) as promotors,controlled conditions enabled the formation of two sets of valuable heterocycles from the tandem transformation of enaminones and *** key to success was the identification of the reaction parameters,in which the imine intermediate which was formed by transient halogenation coupling and substitution processes underwent either aldol condensation/annulation or imine hydrolysis/aldol *** additives NH_(4)Cl or Fe_(2)(SO_(4))_(3) controlled the unique selectivity of this reaction.A broad substrate scope of enaminones and salicylaldehydes has been employed in this reaction,demonstrating excellent functional group tolerance and versatility.
A pivotal problem in the Internet of Things (IoT) is resource allocation, where the goal is to optimize allocation strategies of IoT resources. In general, resource allocation problems are formulated as constrained op...
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