Investigation on relations between grain crushing amount and void ratio change of granular materials in one-dimensional compression and creep tests

Grain crushing plays an important role in one-dimensional (1D) compression and creep behaviors of granular materials under high stress. It is clear that the macro-properties of granular materials are closely related to the micro-fracture properties of grains in 1D compression and creep tests. In this paper, a series of 1D compression and creep tests were performed on Ottawa sand to investigate the deformation and grain crushing properties of granular materials, and it shows that the void ratio is correlated to the grain crushing amount (the quantity of crushed grains) for granular materials subjected to grain crushing. The test results, combining with the existing test data related to grain crushing of granular materials, were used to verify the relation. Moreover, the implications of these relations on the yield of granular material, and the equivalent effect of stress and time in changing soil fabric are presented.

Effects of particle size on crushing and deformation behaviors of rockfill materials

Strength and deformation behaviors of rockfill materials,key factors for determining the stability of dams,pertain strongly to the grain crushing characteristics.In this study,single-particle crushing tests were carried out on rockfill materials with nominal particle diameters of 2.5 mm,5 mm and 10 mm to investigate the particle size effect on the single-particle strength and the relationship between the characteristic stress and probability of non-failure.Test data were found to be described by the Weibull distribution with the Weibull modulus of 3.24.Assemblies with uniform nominal grains were then subjected to one-dimensional compression tests at eight levels of vertical stress with a maximum of 100 MPa.The yield stress in one-dimensional compression tests increased with decreasing the particle size,which could be estimated from the single-particle crushing tests.The void ratio-vertical stress curve could be predicted by an exponential function.The particle size distribution curve increased obviously with applied stresses less than 16 MPa and gradually reached the ultimate fractal grading.The relative breakage index became constant with stress up to 64 MPa and was obtained from the ultimate grading at the fractal dimension(a?2:7).A hyperbolical function was also found useful for describing the relationship between the relative breakage index and input work during one-dimensional compression tests.

A Nonlinear Magneto-Mechanical Coupled Constitutive Model for the Magnetostrictive Material Galfenol

In order to predict the performance of magnetostrictive smart material and pushits applications in engineering, it is necessary to build the constitutive relations for themagnetostrictive material Galfenol. For Galfenol rods under the action of the pre-stress andmagnetic field along the axial direction, the one-dimensional nonlinear magneto-mechanicalcoupling constitutive model is proposed based on the elastic Gibbs free energy, where theTaylor expansion of the elastic Gibbs free energy is made to obtain the polynomial forms. Andthen the constitutive relations are derived by replacing the polynomial forms with the propertranscendental functions based on the microscopic magneto-mechanical coupling mechanism.From the perspective of microscopic mechanism, the nonlinear strain related to magneticdomain rotation results in magnetostrictive strain changing with the pre-stress among theelastic strains induced by the pre-stress. By comparison, the predicted stress-strain,magnetostrictive strain, magnetic induction and magnetization curves agreed well withexperimental results under the different pre-stresses. The proposed model can describe notonly the influences of pre-stress on magnetostrictive strain and magnetization curves, butalso nonlinear magneto-mechanical coupling effect of magnetostrictive materialsystematically, such as the Young’s modulus varying with stress and magnetic field. In theproposed constitutive model, the key material constants are not chosen to obtain a good fitwith the experimental data, but aremeasured directly by experiments, such as the saturationmagnetization, saturation magnetostrictive coefficient, saturation Young’s modulus, linearmagnetic susceptibility and so on. In addition, the forms of the new constitutive relationsare simpler than the existing constitutive models. Therefore, this model could be appliedconveniently in the engineering applications.

One-dimensional perovskite-based Li-ion battery anodes with high capacity and cycling stability

Perovskite,widely used in solar cells,has also been proven to be potential candidate for effective energy storage material.Recent progress indicates the promise of perovskite for battery applications,however,the specific capacity of the resulting lithium-ion batteries must be further increased.Here,by adjusting the dimensionality of perovskite,we fabricated high-performing one-dimensional hybrid perovskite C_(4)H_(20)N_(4)PbBr_(6) based lithium-ion batteries,with the first specific capacity as high as 1632.8 mAh g^(-1)and a stable specific capacity of 598.0 mAh g^(-1)after 50 cycles under the condition of the constant current density of 150 mA g^(-1).The stable specific capacity is 2.36 times higher than that of the three-dimensional perovskite CH_(3)NH_(3)PbBr_(3)(253.2 mAh g^(-1)),and 1.6 times higher than that of the commercialized graphite electrode(372 mAh g^(-1)).The structure difference and the associated ion diffusivity are revealed to substantially affect the specific capacity of the perovskite-based lithium-ion battery.Our study opens up new directions for the applications of hybrid perovskites in energy storage devices.

One-dimensional Li_(3)VO_(4)/carbon fiber composites for enhanced electrochemical performance as an anode material for lithium-ion batteries

Lithium vanadium oxide(Li_(3)VO_(4))has gained attention as an alternative anode material because of its higher theoretical capacity(592 mAh g^(−1)),moderate ionic conductivity(∼10^(−4)S cm^(−1)),and lower working voltage range(∼0.5–1.0 V vs.Li/Li^(+))in comparison to other metal oxides.However,there are disadvantages to using Li_(3)VO_(4)as an anode material,such as low initial Coulombic efficiency and poor rate performance that is attributed to its low electronic conductivity(<10^(−1)0 S cm^(−1)).In the present study,the synthesis of one-dimensional Li_(3)VO_(4)electrode was performed via a facile method by using oxidized vapor grown carbon fiber as a template and the formation of the outer shells of conductive carbon via chemical vapor deposition technique.In a half-cell configuration,the prepared Li_(3)VO_(4)composites exhib-ited an enhanced electrochemical performance with a reversible capacity of 516.2 mAh g^(−1)after 100 cycles at a rate of 0.5 C within the voltage range of 0.01–3.0 V.At a high rate of 5 C,a large reversible capacity of 322.6 mAh g^(−1)was also observed after 500 cycles.The full cell(LVO/VGCF16-C||LiCoO_(2))using LiCoO_(2)as the cathode showed competitive electrochemical performance,which demonstrates its high potential in commercial applications.

Design and fabrication of one-dimensional focusing X-ray compound lens with A1 material

A method based on Fourier spectrum analysis for predicting the performances of the X-ray compound lenses is briefly introduced, the theoretical result obtained is the same as that of Fresnel-Kirchhoff approach. A kind of technique named moulding is developed for fabricating the one-dimensional (1D) compound X-ray lens with Al material and the fabrication process is presented. In addition, a two-time coating method is used to improve the numerical apertures of the compound lenses. Furthermore, the focusing performance of the Al compound X-ray lens under the high energy X-rays is measured.

Intriguing one-dimensional electronic behavior in emerging two-dimensional materials

Tomonaga-Luttinger liquid(TLL),a peculiar one-dimensional(1D)electronic behavior due to strong correlation,was first studied in 1D nanostructures and has attracted significant attention over the last several decades.With the rise of new two-dimensional(2D)quantum materials,1D nanostructures in 2D materials have provided a new platform with a well-defined configuration at the atomic scale for studying TLL electronic behavior.In this paper,we review the recent progress of TLL electronic features in emerging 2D materials embedded with various 1D nanostructures,including island edges,domain walls,and 1D moirépatterns.Specifically,novel physical phenomena,such as 1D edge states in 2D transition metal dichalcogenides(TMDs),helical TLL in 2D topological insulators(2DTI),and chiral TLL in 2D quantum Hall systems,are described and discussed at the nanoscale.We also analyze challenges and opportunities at the frontier of this research area.

One-Dimensional Metal-Organic Framework for High-Efficiency Electrocatalytic Reduction of CO_(2)to CO

Comprehensive Summary Electrocatalytic reduction of CO_(2)to valuable products possesses huge potential to alleviate environmental and energy crisis.It is well known that Ag favors the conversion of CO_(2)to CO but the exposed active sites and stability are still rather limited.In this study,a novel one-dimensional Ag-based metal-organic framework(1D Ag-NIM-MOF)was successfully synthesized and used in the electrocatalytic CO_(2)reduction reaction(CO_(2)RR)for the first time.As a result,the Faradaic efficiency of CO achieved 94.5%with current density of 12.5 mA·cm^(-2)in an H-type cell and 98.2%with current density of 161 mA·cm^(-2)in a flow cell at–1.0 V(vs.RHE),which stands as a new benchmark of Ag-based MOFs in the electrocatalytic CO_(2)RR.The excellent performance of 1D Ag-NIM-MOF is attributed to its peculiar one-dimensional structure,which is beneficial for diffusion of reactants and products,and exposure of much more catalytic sites.Compared to commercial Ag nanoparticles,1D Ag-NIM-MOF exhibits superior electrocatalytic CO_(2)RR performance with higher catalytic activity and stability.

"Three-in-One" Multi-Scale Structural Design of Carbon Fiber-Based Composites for Personal Electromagnetic Protection and Thermal Management

Wearable devices with efficient thermal management and electromagnetic interference(EMI) shielding are highly desirable for improving human comfort and safety. Herein, a multifunctional wearable carbon fibers(CF) @ polyaniline(PANI)/silver nanowires(Ag NWs) composites with a “branch-trunk” interlocked micro/nanostructure were achieved through "three-in-one" multi-scale design. The reasonable assembly of the three kinds of one-dimensional(1D) materials can fully exert their excellent properties i.e., the superior flexibility of CF, the robustness of PANI, and the splendid conductivity of Ag NWs. Consequently, the constructed flexible composite demonstrates enhanced mechanical properties with a tensile stress of 1.2 MPa, which was almost 6 times that of the original material. This is mainly attributed to the fact that the PNAI(branch) was firmly attached to the CF(trunk) through polydopamine(PDA), forming a robust interlocked structure. Meanwhile, the composite possesses excellent thermal insulation and heat preservation capacity owing to the synergistically low thermal conductivity and emissivity. More importantly, the conductive path of the composite established by the three 1D materials greatly improved its EMI shielding property and Joule heating performance at low applied voltage. This work paves the way for rational utilization of the intrinsic properties of 1D materials, as well as provides a promising strategy for designing wearable electromagnetic protection and thermal energy management devices.

One-dimensional HKUST-1 nanobelts from Cu nanowires

The controllable synthesis of one-dimensional(1D) structural morphology of metal-organic frameworks(MOFs) is significant for its application in catalysis,sense and gas separation.In this communication,we report a simple and moderate synthetic strategy to obtain uniform HKUST-1 nanobelts(NBs) by using copper nanowires(Cu NWs) as a metal source as well as a template.The control experiments showed that synergy between metal dissolution rate and crystal formation plays a key role in the formation of nanobelts.Our study represents an attractive synthetic strategy of 1 D MOFs-based material for applications.

Orientation-dependent electromagnetic properties of basalt fibre/nickel core-shell heterostructures

The influence of orientation on electromagnetic properties of basalt fibre/nickel core-shell heterostructures prepared by a simple electroless plating method is investigated. For comparison, the same investigation is also performed on naked basalt fibres. For electromagnetic measurement, the directions of basalt fibre/nickel and naked basalt fibres are parallel, random and perpendicular to the direction of external electric field, termed E11 sample, random sample and E⊥ sample, respectively. Electromagnetic anisotropy can be clearly observed in the basalt fibre/nickel core-shell heterostructures, while electromagnetic properties of naked basalt fibres are unrelated to the orientation. The E⊥ basalt fibre/nickel shows the highest dielectric loss but the lowest magnetic loss, and E11 basalt fibre/nickel exhibits the highest magnetic loss but the lowest dielectric loss. The dielectric loss of E⊥ basalt fibre/nickel is several times as large as that of Eli basalt fibre/nickel, which could be attributed to the increase of polarization relaxation time as a consequence of the nanosize-confinement effect. The magnetic loss of E11 basalt fibre/nickel is even one order of magnitude higher than that of E⊥ basalt fibre/nickel, which originates mainly from the natural magnetic resonance of basalt fibre/nickel core-shell heterostructures.

Quasi one-dimensional van der Waals gold selenide with strong interchain interaction and giant magnetoresistance

The atomic structure of quasi one-dimensional(1D) van der Waals materials can be regarded as the stacking of atomic chains to form thin flakes or nanoribbons, which substantially differentiates them from typical two-dimensional(2D) layered materials and 1D nanotube/nanowire array. Here we present our studies on quasi 1D gold selenide(AuSe) that possesses highly anisotropic crystal structure, excellent electrical conductivity, giant magnetoresistance, and unusual reentrant metallic behavior. The low inplane symmetry of AuSe gives rise to its high anisotropy of vibrational behavior. In contrast, quasi 1D AuSe exhibits high in-plane electrical conductivity along the directions of both atomic chains and perpendicular one, which can be understood as a result of strong interchain interaction. We found that AuSe exhibits a near quadratic nonsaturating giant magnetoresistance of 1841% with the magnetic field perpendicular to its in-plane. We also observe unusual reentrant metallic behavior, which is caused by the carrier mismatch in the multiband transport. Our works help to establish fundamental understandings on quasi 1D van der Waals semimetallic AuSe and identify it as a new candidate for exploring giant magnetoresistance and compensated semimetals.

Geometric stability and electronic structure of infinite and finite phosphorus atomic chains

One-dimensional mono- or few-atomic chains were successfully fabricated in a variety of two-dimensional materials, like graphene, BN, and transition metal dichalcogenides, which exhibit striking transport and mechanical properties. How- ever, atomic chains of black phosphorus （BP）, an emerging electronic and optoelectronic material, is yet to be investigated. Here, we comprehensively considered the geometry stability of six categories of infinite BP atomic chains, transitions among them, and their electronic structures. These categories include mono- and dual-atomic linear, armchair, and zigzag chains. Each zigzag chain was found to be the most stable in each category with the same chain width. The mono-atomic zigzag chain was predicted as a Dirac semi-metal. In addition, we proposed prototype structures of suspended and sup- ported finite atomic chains. It was found that the zigzag chain is, again, the most stable form and could be transferred from mono-atomic armchair chains. An orientation dependence was revealed for supported armchair chains that they prefer an angle of roughly 35°-37° perpendicular to the BP edge, corresponding to the [110] direction of the substrate BP sheet. These results may promote successive research on mono- or few-atomic chains of BP and other two-dimensional materials for unveiling their unexplored physical properties.

Properties of Defect Modes in Periodic Lossy Multilayer with Negative-Index-Materials

Employing the characteristic matrix method, this study investigates transmission properties of onedimensional defective lossy photonic crystals composed of negative and positive refractive index layers with one lossless defect layer at the center of the crystal. The results of the study show that as the refractive index and thickness of the defect layer increase, the frequency of the defect mode decreases. In addition, the study shows that the frequency of the defect mode is sensitive to the incidence angle, polarization, and physical properties of the defect layer, but it is insensitive to the small lattice loss factor. The peak of the defect mode is very sensitive to the loss factor, incidence angle, polarization, refractive index, and thickness of the defect layer. This study also shows that the peak and the width of the defect mode are affected by the numbers of the lattice period and the loss factor. The results can lead to designing new types of narrow filter structures and other optical devices.

Edge engineering in chemically active two-dimensional materials

When "cut off" continuous and uniform basal plane of two-dimensional(2D)materials,edges appear at cross-sections.Such edges with unique one-dimensional(1D)structures and bound-states significantly alter materials’local chemical activities and have been extensively investigated as model platforms for investigating structure–property–performance relationships for chemistry.Many interesting phenomena have been discovered in the past decades,highlighting the importance of interactions between active species and edge atoms at the atomic level and making 1D edges as emerging catalysts with high efficiency,promising candidates for battery and electrochemical contacts.Here,this review focuses on the recent progress of edge synthesis and structural engineering methods,understanding of edge structure–activity mechanisms,and potential applications using edge sites.Challenges and prospects are also envisioned.

Crystal Structure of[Cd(pom)_2Cl_2]

Catena-[bis (3-methyl-4-nitropyridine N-oxide ) cadmiumdichloride],[Cd(C_6H_6N_2O_3)_2Cl_2], M_r= 491. 56, monoclinic , P2_1, a= 3. 799 (3), b= 29. 231 ( 9),c=7. 679(5) A, β=100. 19(6)°, V=839. 4 A￣3, Z=2, D_c= 1. 94 g/cm￣3, λ(MoKa)= 0. 71069 A, F(000) =484, P(MoKa) = 16. 5 cm￣(-1), final R=0. 038 for 1202 Observed reflections, T= 296K. The Cd atom is octahedrally coordinated by two O atoms from the trans 3-methyl-4-nitropyridine N-oxide (pom) ligands in the axial positions and four Cl atoms lying in the equatorial plane. The coordination octahedra form chains along the short a axis by edge sharing through the Cl atoms.

One dimensional pea-shaped NiSe_(2) nanoparticles encapsulated in N-doped graphitic carbon fibers to boost redox reversibility in sodium-ion batteries

In recent years,sodium-ion batteries(SIBs)have emerged as a promising technology for energy storage systems(ESSs)because of the abundance and affordability of sodium.Recently,metal selenides have been studied as promising high-performance conversion-type anode materials in SIBs.Among them,nickel se-lenide(NiSe_(2))has received considerable attention due to its high theoretical capacity of 495 mAh g^(-1)and conductivity.However,it still suffers from poor cycling stability because of the low electrochemical reactivity,large volume expansion,and structural instability during cycles.To address these challenges,NiSe_(2)nanoparticles encapsulated in N-doped graphitic carbon fibers(NiSe_(2)@NGCF)were synthesized by using ZIF-8 as a template.NiSe_(2)@NGCF showed a high discharge capacity of 558.3 mAh g^(-1)with a fading rate of 0.14%per cycle after 200 cycles at 0.5 A g^(-1)in 0.01-3.0 V.At a very high current density of 5 A g^(-1),the capacity still displayed excellent long-term cycle life with a discharge capacity of 406.1 mAh g^(-1)with a fading rate of 0.016%per cycle after 3000 cycles.The mechanism of the excellent electrochem-ical performance of NiSe_(2)@NGCF was thoroughly investigated by ex-situ XRD,TEM,and SEM analyses.Furthermore,NiSe_(2)@NGCF//Na_(3)V_(2)(PO_(4))_(3)full-cell also delivered an excellent reversible capacity of 378.7 mAh g^(−1)at 0.1 A g^(−1)after 50 cycles,demonstrating its potential for practical application in SIBs.

Hierarchical design of FeCo-based microchains for enhanced microwave absorption in C band

Microwave absorbing materials(MAMs)has been intensively investigated in order to meet the requirement of electromagnetic radiation control,especially in S and C band.In this work,FeCo-based magnetic MAMs are hydrothermally synthesized via a magnetic-field-induced process.The composition and morphology of the MAMs are capable of being adjusted simultaneously by the atomic ratio of Fe2+to Co2+in the precursor.The hierarchical magnetic microchain,which has a core–shell structure of twodimensional FexCo1−xOOH nanosheets anchored vertically on the surface of a one-dimensional(1D)Co microchain,shows significantly enhanced microwave absorption in C band,resulting in a reflection loss(RL)of lower than−20 dB at frequencies ranging from 4.4 to 8.0 GHz under a suitable matching thickness.The magnetic coupling of Co microcrystals and the double-loss mechanisms out of the core-shell structure are considered to promote the microwave attenuation capability.The hierarchical design of 1D magnetic MAMs provides a feasible strategy to solve the electromagnetic pollution in C band.

Thermal Growth and Nanomagnetism of the Quasi-one Dimensional Iron Oxide

Quasi-one dimensional iron oxide nanowires with flat needle shape were synthesized on the iron powders by a rather simple catalyst-free thermal oxidation process in ambient atmosphere. The characterization by field emission scanning electron microscopy （FE-SEM）, X-ray photoelectron spectroscopy （XPS）, X-ray diffraction （XRD）, Raman and high-resolution transmission electron microscopy （HRTEM） revealed that these nanos- tructures are single crystalline α-Fe2O3. The various dimensions with 40-170 nm in width and 1-8 μm in length were obtained by tuning the growth temperature from 280 to 480℃. A surface diffusion mechanism was proposed to account for the growth of quasi-one dimensional nanostructure. The typical α-Fe203 nanowires synthesized at 430℃ had a reduced Morin temperature TM of 131 K in comparison with their bulk counterpart. The coercivitis Hc of these nanowires are 321 and 65 Oe at 5 and 300 K, respectively. The temperature of synthesis also has important effects on the magnetic properties of these nanowires.

One dimensional carbon-based composites as cathodes for lithium-sulfur battery

Lithium-sulfur batteries(LSBs),owing to their much higher energy density compared to the traditional lithium-ion battery,are deemed as one of the most promising candidates for the energy storage system.However,several issues including shuttle effect,lithium dendrites,and volumetric expansion seriously impede the commercial applications of LSBs.One-dimensional carbon materials(1DCMs)have been widely used as the matrix material for LSBs due to their high surface area,superior conductivity,good flexibility,excellent mechanical stability,and functional modifiability.In this review,the recent progress in 1D carbon-based composites as cathode including metal compounds/1DCMs,MOFs/1DCMs,MXenes/1DCMs,and polymers/1DCMs were discussed.Different strategies for polysulfide confinement and analysis of the functions of various components in the composites were summarized detailly.In the end,the current challenges of LSBs were systematically summarized,and the future outlooks were proposed,aiming at providing a comprehensive insight into the design of new host materials for nextgeneration LSBs.