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In this paper, the first-principles calculations based on DFT were employd to investigate the elasticity characteristics of AgW20 alloy. The elasticity constants of the single crystals are calculated using the finite strain method and Voigt – Reuss – Hill (VRH) approach. The universal anisortropic index (AU ), shear anisortropic index, orientation dependency of Young’s modulus, bulk modulus were used to characterize elasticity anisortropy behaviors. The calculated elasticity properties of AgW20 alloy show a remarkable elasticity anisortropy for AgW20 alloy.

We demonstrate the possibility of dual-band unidirectional reflectionlessness in a non-Hermitian quantum system composed of a plasmonic waveguide and two end-coupled plasmonic cavities (PCs). Our scheme exhibits dual-band unidirectional reflectionlessness can be obtained at exceptional points by properly adjusting the coupling strength between two PCs, the ratio of decay rates of two PCs, and the ratio of plasmonic cavity-waveguide coupling strengths. As a valuable feature, the quality factor reaches to ∼175.4 in forward direction, while the backward quality factor is close to ∼188.2.

We propose a scheme to realize the active controlled dual-band unidirectional reflectionlessness at exceptional points by classical driving field in a non-Hermitian quantum system that consists of two Λ-type three-level quantum dots side coupled to a plasmonic waveguide. We demonstrate that the dual-band unidirectional reflectionlessness can be controlled by appropriately tuning classical driving field, phase shift between two quantum dots, dissipations of two quantum dots, and quantum dot-waveguide coupling strengths. Furthermore, the dual-band unidirectional reflectionlessness spectra with quality factors of ∼375.40 and ∼402.59 can be obtained in the forward and backward directions, respectively.

In order to provide a dry operation environment for the construction of high pile cap in water, the steel cofferdam must be completely sealed when working underwater. Therefore, in order to avoid leakage of cofferdam due to welding defects, high requirements are put forward for the splicing weld quality of cofferdam components. Ultrasonic testing is widely used in the detection of cofferdam welds because of its strong environmental adaptability, convenient operation, high automation level and strong data processing ability. This paper introduces the application of ultrasonic detection technology in steel cofferdam, which has achieved good results.

Laser-induced breakdown spectroscopy (LIBS) was used to decipher the unique multi-elemental characteristics of Juncus effusus L. The spectral fingerprints of Juncus effusus L. were established based on elemental microanalysis via LIBS. Microanalysis and multimode sampling methodologies were designed in this study. The relative standard deviation (RSD) approach was performed to optimize the multi-shot measurements. Taking advantage of the capability with no or minimal sample pre-treatment of LIBS, a thermodynamic chart of four elements (Mg, Ca, Ba, and Na) was created from twelve collection regions. The diagram of elemental distribution on a micro-scale was generated to explore the nature of Juncus effusus L. by LIBS. The results demonstrated that LIBS is a promising technique for rapid elemental microanalysis of heterogeneous samples.

Traditional manual method for mapping is time consuming and has low precision. In order to increase the efficiency, this paper proposes a semi-automatic road lane marking detection based on point-cloud data. This approach requires simple interface interaction, and since point cloud data is memory intensive, we convert it to RGB images using the intensity and height of the 3D point cloud. Then, in the interface, the user needs to click a point around the detection line and generate image regions of interest. Finally, the image is filtered using a specific filter to obtain a convolved value for each point, and the position with the largest convolution value is the point at the position of the reticle. In this way, we get a point on the road marking, and multiple point connections generate the road markings on the map. Multiple experiments were performed on data from different routes obtained by different sensors, such as veledyne-64, veledyne-16, to verify the effectiveness of road lane marking detection based on point cloud data for mapping..

Carbon nanotubes (CNTs) are emerging transporters for delivery of gene and drug. The degradable polycation functionalized CNTs (CNTs-HDDAPEI) were fabricated by grafting ester bond-containing polyethyleneimine (HDDAPEI). Fourier transform infrared spectroscopy, Raman spectrum, transmission electron microscopy and thermogravimetric analysis were used to characterize the degradable polyethyleneimine decorated CNTs. Compared with pristine CNTs, the CNTs-HDDAPEI displayed better dispersability and stability in water.

There is a long-term controversy on sedimentary environment of Late Carboniferous-Permian in Santanghu Basin. In this paper, we study on the geochemical characteristics of source rocks from Harjiawu Formation of Upper Carboniferous and Lucaogou Formation of Middle Permian in Santanghu Basin. The results show that the abundance and maturity of organic matter of source rocks in Harjiawu Formation are both high, which shows excellent source rocks. In contrast, the abundance of organic matter from source rocks in Lucaogou Formation is relatively low and the maturity of organic matter is between immature and mature, which suggests good-excellent source rocks. The organic geochemical characteristics indicate the freshwater lacustrine environment of Late Carboniferous, while Lucaogou Formation is the high salinity lacustrine environment. In addition, magmatic-hydrothermal activity may result in the water salinization of Permian.

We propose a scheme for achieving unidirectional reflectionlessness and perfect nonreciprocal absorption at the exceptional point, based on near-field coupling in a stacked asymmetric nanostrip metamaterial structure. The result of theoretical analysis shows good agreement with a numerical simulation. Unidirectional reflectionlessness is realized well in wide ranges of the parameters s and a. The absorbance reaches ~1 in the +z incident direction, and the contrast ratio of the reflectance between the +z and −z incident directions is ~1.

A vast body of fusion data has been analyzed for different projectiles and target nuclei. It is indicated that the sub-barrier fusion depends on the fusion Q-value. In terms of a recently introduced fusion Q-value rule and an energy scaling reduction procedure, the experimental fusion excitation functions are reduced and compared with each other. It is found that the reduced fusion excitations of selected fusion systems show a similar trend. The fusion data for massive nuclei are in agreement with the Q-value rule. In the fusion process, the Q contribution should be considered. Within this approach, the sub-barrier fusion cross sections of most fusion systems can be predicted without involving any structure effects of colliding nuclei. Instances of disagreement are presented in a few fusion systems. The use of the energy scaling as a criterion of possible experimental data inconsistency is discussed. More precise experimental fusion data need to be measured.

We propose a scheme for realizing plasmonic electromagnetically induced transparency (EIT)-like effects at optical frequencies in a stacked metamaterial that consists of two silver rings. The two silver rings are excited strongly by an incident wave. Based on Fabry–Perot (FP) resonance coupling between the two resonators, polarization-independent EIT-like effects appear at optical frequencies.

The autonomy and property of atoms/molecules adsorbed on the surface of a microcantilever can be probed by measuring its resonance frequency shift due to adsorption. The resonance frequency change of a cantilever induced by chemisorption is theoretically studied. Oxygen chemisorbed on the Si(100) surface is taken as a representative example. We demonstrate that the resonant response of the cantilever is mainly determined by the chemisorption-induced bending stiffness variation, which depends on the bond configurations formed by the adsorbed atoms and substrate atoms. This study is helpful for optimal design of microcantilever-based sensors for various applications.

Based on the coupling of two distant three-level atoms in two separate optical cavities connected with two optical fibres, schemes on the generation of several two-qubit logic gates are discussed under the conditions of Δ = δ − 2νcos πk/2 g/2 and ν ~ g. Discussion and analysis of the fidelity, gate time and experimental setups show that our schemes are feasible with current optical cavity, atomic trap and optical fibre techniques. Moreover, the atom—cavity—fibre coupling can be used to generate an N-qubit nonlocal entanglement and transfer quantum information among N distant atoms by arranging N atom—cavity assemblages in a line and connecting each two adjacent cavities with two optical fibres.

We propose to implement a highly entangled cluster state (HECS) with only one step based on the resonant interactions among N two-level ions and two different standing-wave lasers with a phase difference of π/2. The time for preparation of the HECS is related only to the frequency of the vibrational mode ν (i.e. t=2π/ν). We can ensure that the preparation time is short enough by setting the larger vibrational mode frequency ν to neglect the effect of the decoherence of the qubits. During the process of preparing the HECS, the heating effect of the vibrational mode can be neglected and the initial qubits need only one evolution with the time interval t. The reduced operation steps and the shorter preparation time make the present scheme more feasible in experiments.

Microcantilever-based techniques can be used to explore the autonomy and property of molecules (e.g. DNA and single actin filaments) adsorbed on a surface. A theoretical model is presented here to predict the resonance frequency of a cantilever induced by physically adsorbed atoms/molecules. The cantilever is modelled as a sandwich beam containing two surface layers of a finite thickness and a bulk layer between them. It is found that the resonance frequency shift depends sensitively on both the mass and bending stiffness variations of the cantilever induced by the adsorbed atoms/molecules. The adsorptions of O atoms on Si(1 0 0), of O atoms on Au(1 0 0) and of H atoms on Au(1 0 0) are taken as three representative examples. We demonstrate that physisorption can induce distinctly different resonant responses of cantilevers, depending not only on the adatoms but also on the substrate material. This study is helpful for the optimal design of microcantilever-based measurement techniques.

A femtosecond optical Kerr effect experiment has been used to study the dynamic process of third-order optical nonlinearity for organic solvents acetone, acetonitrile, alcohol, benzene, chloroform, dichlomathane, dimenthylsulfoxande, dioxane, ethanol, and methanol, etc. The nonlinear refractive index for the solvents at femtosecond time scale was measured.