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Three kinds of nano-concrete, i.e., 2.0% nano-SiO2 doped, 2.0% nano-CaCO3 doped and 1.0% nano-SiO2-1.0% nano-CaCO3 co-doped concretes (NS, NC, NSC) were prepared for a study on static property and dynamic property under different strain rates (50–130 s−1) using HYY series hydraulic servo test system and Φ100 mm split Hopkinson pressure bar test system, and a comparison with plain concrete (PC) as well. The results have shown that under static load, as compared with PC, NC has both strength and elastic modulus increased obviously, while NS has strength decreased and elastic modulus increased, and under dynamic load, there is an obvious strain rate effect for the dynamic compressive strength, impact toughness, energy dissipation and impact failure mode of concrete. Under the same strain rate, the dynamic compressive strength, peak strain, impact toughness and energy dissipation of NC are significantly increased, while its dynamic elastic modulus is decreased. Compared with PC, NS has dynamic compressive strength, peak strain, impact toughness and energy dissipation decreased, and dynamic elastic modulus increased, NC has static and dynamic mechanical properties improved, NS has static and dynamic mechanical properties weakened, and NSC is between PC and NC in static and dynamic mechanical properties, but generally improved. Doped with nano-CaCO3, NC has compactness improved, weak areas reduced, and pore size distribution optimized, while doped with nano-SiO2, NS has obvious internal weak areas, with pore structure degraded.

In order to improve the microwave deicing efficiency of airport road surface concrete, the method of incorporating carbon fiber materials of different doping amounts and lengths into concrete is proposed. The test method is optimized by using a fiber-optic temperature sensor and a self-developed open microwave deicing vehicle, and the effect of the coupling effect of different carbon fiber doping and length on the microwave deicing efficiency of concrete is studied. The results of the study show that the appropriate amount of carbon fiber blended into the concrete can significantly improve the microwave deicing efficiency, and the reasonable use of carbon fiber-modified concrete can achieve the purpose of efficient deicing of the airport road surface. By analyzing the temperature rise curve, temperature rise rate curve, deicing effect, and infrared thermography of the microwave deicing process, combined with the “heat generation-heat dissipation” theory, the microwave deicing is divided into four stages: concrete wave absorption, water layer formation, ice thinning, and ice breaking and ice melting. In the process of microwave deicing of concrete, changing the length of carbon fiber and the amount of doping will have a greater impact on the rate of temperature rise and deicing range, but the shape of deicing remains basically the same, mainly spindle-shaped. When the length of carbon fiber is short, it is not conducive to the absorption of microwave by concrete, and with the increase of fiber length and doping amount, the wave absorption performance of carbon fiber-modified concrete on the airport road surface is gradually improved; when the fiber length is 0.6 cm and the fiber doping amount is 2‰, the wave absorption performance is the best, and the deicing rate is 1.82 times of ordinary concrete, and the deicing area is 1.2 times of ordinary concrete.

Strong light–matter coupling manifested by Rabi splitting has drawn considerable interest owing to its fundamental significance for impressive interaction enhancement in the fields of ultrafast active plasmonic devices and quantum information. In this paper, we investigate the coherent optical properties of a plasmonic system consisting of periodic metal nanoparticle arrays covered by a WS2 thin film of atomic layer thickness. The coupling factor, energy splitting, and temporal dynamics of this coherent coupling phenomenon are quantitatively revealed by finite-difference time-domain (FDTD) simulation and a full quantum mechanical model proves that the exciton behavior of the fermionic quantum emitter WS2 is carefully modulated by bosonic surface lattice resonances. This work may pave the way for coherent modulation of polariton and plasmon devices and can potentially open up diverse exciting possibilities like nanoscale light sources, single-photon emitters, and all-optical transistors.

In this paper, we demonstrate an active switching of extremely high Q-factor Fano resonances using vanadium oxide (VO2)-implanted THz asymmetric double C-shaped metamaterial (MM) structures. The simulation results indicate the highly temperature-sensitive nature of the double Fano resonances that can be switched at very low external thermal pumping (68 &deg, C), which is only slightly higher than room temperature. We employ the surface current and electric field distributions of the structure to analyze the physical mechanism of the observed switching behavior in the thermally excited Fano MMs. More importantly, by optimizing the asymmetric parameter (offset length), the linewidth of the Fano resonance can reach only 0.015 THz and the Q-factor is as high as 98, which is one order of magnitude higher than that of the traditional MMs. The findings of this work would enable a thermally-induced high-Q Fano resonance MMs for ultra-sensitive sensors, modulators, low threshold switching in metadevices.

Arrays of metal–dielectric–metal (MDM) multilayer nanostructure can support various kinds of plasmonic modes including in-plane (IP) localized/delocalized surface plasmons or lattice resonances, photonic waves, as well as out-of-plane (OP) plasmon modes. Hybridization between different modes offers rich physics such as lasing, sub- and super-radiant modes, and efficient light absorption. While interplays between different sets of in-plane modes have been intensively investigated, the interaction between in-plane and out-of-plane modes is rarely explored. Here, we propose a MDM nanostructure with 2D nanocylinder array and study in detail the strong coupling between the in-plane photonic modes at the dielectric layer and the out-of-plane plasmon modes excited at the cylinder sidewalls. We demonstrate the strong coupling between the localized second-order IP mode and the first-order OP mode with a Rabi splitting up to 250 meV in the near-infrared region. A new IP mode arising from the radiative field can induce another kind of strong coupling with OP modes as the cylinder radius is larger than 98 nm. The underlying physics within this plasmon–photon system is quantitatively revealed by the coupled oscillator model and calculated E-field distribution. The proposed MDM system provides a good platform for investigating multimode coupling and nano-optics devices.

A novel adsorbent, tartaric acid modified graphene oxide (GO-TA), was successfully prepared by a simple esterification reaction and applied to remove Cu(II) and Pb(II) metal ions from aqueous solutions. The obtained composites were characterized by Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy and transmission electron microscopy (TEM). Batch experiments were carried out to investigate the effect of pH value, contact time, concentration of metal ions and temperature on Cu(II) and Pb(II) adsorption. The maximum adsorption capacities for Cu(II) and Pb(II) are 374.53 mg g−1 and 125.63 mg g−1, respectively, which were higher than those of pristine graphene oxide (GO). The obtained experimental data showed a good correlation with the Langmuir adsorption model. The adsorption kinetics of Cu(II) and Pb(II) onto GO-TA composite was found to be well fit for the pseudo-second-order model. Moreover, thermodynamic parameters including ΔGθ 0 and ΔSθ> 0, indicating that the adsorption of Cu(II) and Pb(II) onto GO-TA composite was spontaneous and endothermic in nature. All these results indicated that GO-TA composite with such high adsorption efficiency and fast adsorption equilibrium could be used to clean up heavy metal pollution in the future.

Tunable terahertz (THz) functional devices have exhibited superior performances due to the use of active materials, such as liquid crystals, graphene, and semiconductors. However, the tunable range of constitutive parameters of materials is still limited, which leads to the low modulation depth of THz devices. Here, we demonstrate a broadband tunable THz absorber based on hybrid vanadium dioxide (VO2) metamaterials. Unlike other phase change materials, VO2 exhibits an insulator-to-metal transition characteristic and the conductivity can be increased by 4–5 orders of magnitude under external stimulus including electric fields, optical, and thermal pumps. Based on the unique transition character of VO2, the maximum tunable range of the proposed absorber can be realized from 5% to 100% by an external thermal excitation. Meanwhile, an absorption greater than 80% in a continuous range with a bandwidth about 2.0 THz can be obtained when VO2 is in its metal phase at high temperature. Furthermore, the absorber is insensitive to the incident angle up to 50° and such a broadband THz absorber can be used in applications including imaging, modulating, cloaking, and so on.

In this work, a novel activated carbon containing graphene composite was developed using a fast, simple, and green ultrasonic-assisted method. Graphene is more likely a framework which provides support for activated carbon (AC) particles to form hierarchical microstructure of carbon composite. Scanning electron microscope (SEM), transmission electron microscope (TEM), Brunauer–Emmett–Teller (BET) surface area measurement, thermogravimetric analysis (TGA), Raman spectra analysis, XRD, and XPS were used to analyze the morphology and surface structure of the composite. The electrochemical properties of the supercapacitor electrode based on the as-prepared carbon composite were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), charge/discharge, and cycling performance measurements. It exhibited better electrochemical performance including higher specific capacitance (284 F g−1 at a current density of 0.5 A g−1), better rate behavior (70.7% retention), and more stable cycling performance (no capacitance fading even after 2000 cycles). It is easier for us to find that the composite produced by our method was superior to pristine AC in terms of electrochemical performance due to the unique conductive network between graphene and AC.

The Goos–Hanchen shift at the surface of a uniaxially anisotropic left-handed material film is investigated, for the situation of that there is an arbitrary angle between the optical axis and the interface of the material. The analytical expressions of the Goos–Hanchen shifts are derived, for both cases of that the total reflection occurs and does not occur at the first interface. The sign of the Goos–Hanchen shifts in the two situations is analysed. The results show that the Goos–Hanchen shift of the reflected wave is the same as that of the transmitted one for the case that the total reflection does not occur at the first interface; the Goos–Hanchen shift of the transmitted wave oscillates as the thickness of the film is increased, and its overall tendency is increased; the Goos–Hanchen shift of the transmitted wave realizes its absolute maximum when the transmitted wave resonances, the absolute maximum is almost several 10 times of the wavelength of the incident wave; the Goos–Hanchen shift of the transmitted wave is significantly influenced by the incident angle and the angle between the optical axis and the interface.