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As a result of the advantages of the steel fiber reinforced concrete pavement structure, which includes high strength, high stiffness, and high stability, a large number of steel fiber concrete pavements will be used for highway construction in China. As a result, numerous cracks develop, which significantly reduces the life of the road; therefore, the study of the jointing problem is vital. As concrete research on the influence of the load transfer capacity and service life of prefabricated steel fiber reinforced concrete joints on the structural design and use function of the whole and pavement panels, the paper proposes two joint forms, tongue-and-groove and overlap. Using experiments and software, the stress and reflection of prefabricated road panels of the two joint forms are analyzed for different axial loads. The analysis reveals that the maximum tensile stress, shear stress, and deflection of the precast panels of both joint forms increase linearly as the axle load of the vehicle increases, while the service life decreases relatively. The load transfer capacity is independent of the axle load magnitude, and the load transfer capacity difference between the two types of joints is minimal and excellent. [ABSTRACT FROM AUTHOR]

We define the anisotropic structure building unit that encompasses diverse chemical bonds (ABUCB). The ABUCB is highly likely to cause anisotropy in both crystallographic structure and spatial electron distribution, ultimately resulting in enhanced macroscopic optical anisotropy. Accordingly, the (PO3F)2− or (SO3F)− tetrahedron involving the unique P–F or S–F bond serves as such an ABUCB. The distinct chemical bond effectively alters the microscopic nature of the structure building unit, such as polarizability anisotropy, hyperpolarizability, and geometry distortion; this consequently changes the macroscopic second-order nonlinear optical (2nd-NLO) properties of the materials. In this review, we summarize both typical and newly emerged compounds containing ABUCBs. These compounds encompass approximately 90 examples representing six distinct categories, including phosphates, borates, sulfates, silicates, chalcogenides and oxyhalides. Furthermore, we demonstrate that the presence of ABUCBs in DUV/UV NLO compounds contributes to an increase in birefringence and retention of a large band gap, facilitating phase matching in high-energy short-wavelength spectral ranges. On the other hand, the inclusion of ABUCBs in IR NLO compounds offers a feasible method for increasing the band gap and consequently enhancing the larger laser-induced damage threshold. This review consolidates various trial-and-error explorations and presents a novel strategy for designing 2nd-NLO compounds, potentially offering an opportunity for the development of high-performance 2nd-NLO materials. [ABSTRACT FROM AUTHOR]

The discovery of compounds with low thermal conductivity and the understanding of their microscopic mechanisms are of great challenges and scientific significance. Herein, we report a unique ternary sulfide compound, Cu3BiS3, in which all Cu atoms are coordinated within a two‐dimensional [CuS3] triangle plane. This local coordination leads to efficient out‐of‐plane phonon scattering and an ultralow thermal conductivity. Through DFT phonon spectrum calculations and analyses, we reveal that the lowest vibration frequency decreases from 2 THz for high‐dimensional [CuS4] tetrahedral coordinated Cu atoms in CuBiS2 (CN=4, with an average Cu−S bond length of 2.328 Å) to 1.5 THz for low‐dimensional [CuS3] triangular coordinated Cu atoms in Cu3BiS3 (CN=3, with a shorter Cu−S bond length of 2.285 Å). This is due to the out‐of‐plane thermal vibration of the Cu atoms in the latter. Consequently,Cu3BiS3 exhibits one of the lowest values of κlat (0.32 W/m K) among its peer, with a 36 % reduction compared to CuBiS2 (0.50 W/m K). This groundbreaking discovery highlights the significant role of 2D local coordination in reducing thermal conductivity through characteristic out‐of‐plane phonon scattering, while also contributing to a large Grüneisen parameter (2.06) in Cu3BiS3. [ABSTRACT FROM AUTHOR]

Orthokeratology (OK) is becoming a mainstream modality for myopia correction and control, but its underlying mechanism is not yet fully understood. In this study, the biomechanical response of cornea under the OK lens was investigated to further understand the mechanism of OK therapy. Numerical models of the cornea and OK lens with different corneal refractive powers and myopia degrees were established to analyze features and differences of the spatial displacement and stress distribution in different areas of the anterior corneal surface by finite element method. Displacement distributions on the anterior cornea surface with refractive powers of 39.5, 43, 46 D, and myopia degrees of −1.0, −3.0, −6.0 D demonstrate similar deformation trends and nearly rotationally symmetrical attributes of different corneal parameters. Displacement of mid‐peripheral cornea was significantly high compared with that of the central and peripheral cornea, peaking at ~2.4 mm off the corneal apex. The stress increased with the increase in myopia degrees and was significantly large for the myopia degrees of −6.0 D at S1; the stress at S2 and S6 was low and stable and did not differ much at S3; the stress at S4 and S5, however, was extremely high. In summary, simulation result of orthokeratology can effectively evaluate the performance of OK lens and it properly associates with the differential map of the corneal topography. The base curve of the OK lens may also play a role in mid‐peripheral corneal steepening. The design around the OK lens' alignment curve needs to be optimized. [ABSTRACT FROM AUTHOR]

The adsorption properties of common gas molecules (CO, NO, and [N.sub.2]) on the surface of Li-decorated pristine graphene and Li-decorated boron doped graphene are investigated using density functional theory. The adsorption energy, charge transfer, and density of states of gas molecules on three surfaces have been calculated and discussed, respectively. The results show that Li-decorated pristine graphene has strong interaction with CO and [N.sub.2]. Compared with Li-decorated pristine graphene, Li-decorated boron doped graphene exhibit a comparable adsorption ability of CO and [N.sub.2]. Moreover, Li-decorated boron doped graphene have a more significant adsorption energy to NO than that of Li-decorated pristine graphene because of the chemical interaction of the NO gas molecule. The strong interaction between the NO molecule and substrate (Li-decorated boron doped graphene) induces dramatic changes to the electrical conductivity of Li-decorated boron doped graphene. The results indicate that Li-decorated boron doped graphene would be an excellent candidate for sensing NO gas. Key words: Li-decorated pristine graphene, Li-decorated boron doped graphene, new sensor or adsorbent, density functional theory. Nous avons etudie les proprietes d'adsorption de molecules gazeuses courantes (CO, NO, [N.sub.2]) a la surface du graphene vierge complexe a un atome de Li et du graphene dope au bore complexe a un atome de Li au moyen de la theorie de la fonctionnelle de la densite. Nous avons calcule l'energie d'adsorption, le transfert de charge et la densite d'etats des molecules gazeuses pour trois surfaces, et nous discutons respectivement des resultats de ces calculs. Les resultats montrent que le graphene vierge complexe a un atome de Li presente une forte interaction avec le CO et le [N.sub.2]. Le graphene dope au bore complexe a un atome de Li possede une capacite d'adsorption du CO et du [N.sub.2] semblable a celle du graphene vierge complexe a un atome de Li. Cependant, le premier presente une energie d'adsorption du NO plus importante que le dernier en raison de l'interaction chimique avec la molecule de NO gazeux. Cette forte interaction entre la molecule de NO et le substrat--en l'occurrence le graphene dope au bore complexe a un atome de Li--induit des changements marques de la conductivite electrique de ce materiau. Les resultats indiquent que le graphene dope au bore complexe a un atome de Li serait un excellent candidat pour la detection du NO gazeux. [Traduit par la Redaction] Mots-cles : graphene vierge/graphene dope au bore complexes a un atome de Li, nouveau capteur/adsorbant, theorie de la fonctionnelle de la densite., Introduction Detecting gas molecules, particularly for toxic gases, has been in high demand for industrial and civilian purposes. (1-4) An excellent gas sensor should have three characteristics: superior sensitivity, low [...]