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The wave functions, energy levels and matrix elements of Yb+ ions are calculated using the relativistic configuration interaction plus core polarization (RCICP) method. The static and dynamic electric dipole polarizabilities of the ground state and low-lying excited states are determined. Then, the magic wavelengths of the magnetic sublevel 6s1/2,m = 1/2 → 5d3/2,m = ±3/2,±1/2 and 6s1/2,m = 1/2 → 5d5/2,m = ±5/2,±3/2,±1/2 transitions in the linearly, right-handed, and left-handed polarized light are further determined. The dependence of the magic wavelengths upon the angle between the direction of magnetic field and the direction of laser polarization is analyzed.

In the power grid WebGIS application, the graphical display of power grid equipment is one of the most basic functions. However, the massive data brought by the growing number of power grid equipment brings difficulties to both server-side storage and client-side rendering. Aiming at the characteristics of power grid GIS data, this paper presents a Web Worker-based grid WebGIS rendering optimization method and uses a program to implement it. The method improves the rendering speed of the client and optimizes the display effect by marking the displaying rules after data vectorization, simplifying the line data, generating vector tiles dynamically, and station label dodging. The result of the test shows that this method can effectively improve the fluency and user experience of existing power grid GIS applications.

Rare earth elements and the LPSO phase play a significant part in the optimal regulation of the comprehensive performance of the Mg-9Y-1MM-1Zn-0.6Zr (WE91B) alloy, but the high strength of the alloy also brings problems such as difficulties in processing deformation. To determine optimal machining parameters suitable for WE91B, the homogenized alloy was investigated in constant temperature and equal rate compression using the Gleeble-3500 thermal simulation measurement instrument, to study the hot deformation behavior of WE91B alloy in the temperature range of 693-783 K, strain rates of 0.001-1s−1 and maximum deformation of 60%. The deformation activation energy was calculated, the constitutive equation of WE91B alloy was constructed, and the processing map of the alloy was established according to the dynamic material model. The results show that the flow stress curves of the alloy exhibit typical dynamic recrystallization characteristics and the flow stress increases significantly with the increase in strain rate and decrease in deformation temperature. The hot deformation activation energy of WE91B alloy is about 331.605 kJ/mol. From the two aspects of processing map and microstructures after plastic deformation, the optimal processing process of WE91B alloy is T = 783 K and έ = 0.05 s−1.

The swarm intelligence optimization algorithm has obtained good results in practical application in the field of image processing with defect detection, and it has become the focus and hot spot of attention and research in the field of image processing. In this paper, the application of ALO as the representative of the relevant swarm intelligence optimization algorithm is studied to address the problems and shortcomings of image processing technology in the field of object defect detection. By extracting typical defect detection image samples, the effect of the application of the algorithm in sample processing is systematically studied. In addition, the introduction of perturbation strategy and inertia weights in ALO effectively improves the search performance of the algorithm. Finally, this paper analyzes the performance comparison between the commonly used defect detection image processing techniques and the algorithm in this paper by establishing comparative verification experiments. The experimental results show that the image processing strategy constructed in this paper has significant application advantages in the dimensions of image enhancement and image processing applicability.

To solve the problem that the torque pulsation is serious due to the large current error in the period when the duty cycle is calculated by the deadbeat method in the duty cycle dual-vector model predictive current control method, a vector switching method is proposed. The control objective of the proposed method is not to equate the predicted torque current with the reference value under the dead-beat idea, but to reduce the torque current control error by changing the switching time of the voltage vector and ensuring the symmetry of the positive and negative current errors. By deducing the duty cycle, the maximum current errors in a single control cycle before and after vector switching is compared and analyzed. The vector switching method is verified on the Simulink simulation platform and compared with the duty cycle double vector method. The results show that the vector switching method can effectively reduce the intra-cycle torque current tracking error and realize the optimal process control in each cycle.

In the process of large displacement fracture injection, high flow velocity sand-carrying fluid causes serious erosion corrosion to the borehole. Based on the high-speed liquid-solid two-phase erosion experiments, the erosion experiments of single-hole set with flow velocity, sand concentration and grain size, and the three-dimensional profile scanning of the eroded orifice were carried out to investigate the erosion and corrosion expansion law of the high-speed jet orifice. The study shows that the erosion rate increases with the increase of discharge volume, sand concentration and particle size, and the change of discharge volume and sand concentration has the most significant effect on the erosion of the hole. The prediction of the hole expansion law of single hole with sand liquid injection shows that the hole diameter expands to 13mm-19mm after 90min of construction of 8 clusters of 24 holes, while the hole diameter expands to 11.7mm-12.8mm after 90min of construction of 3 clusters of 48 holes. 3 clusters of 48 holes have smaller hole diameter after the same construction time, which is better than 8 clusters of 24 densely packed holes.

The requirements, development, packaging characteristics and existing reliability problems of high density packaging T/R modules are introduced, and the importance of reliability design is recognized. Aiming at the reliability problems of Electro Magnetic Compatibility (EMC), heat dissipation and electrostatic discharge, the reliability design and simulation scheme are given, and some cases are provided. Through design analysis and improvement, the reliability of 3D high density packaging T/R modules can be effectively improved.

China has achieved quite good results in the research and application of information technology and other fields. The continuous advancement of technologies such as AI, 5G communications, and cloud computing have played a key role in the development of intelligence, convenience, and innovation in various industries in China. The application of AI as a technical means in the Internet industry has been relatively mature and has achieved relatively good results. However, AI has not yet achieved satisfactory results in the development and upgrading of the manufacturing industry. As the most critical industry in the real economy, the manufacturing industry has played a decisive role in the sustainable development of China’s real economy. Therefore, it is necessary to promote the deep integration of AI technology and manufacturing and to further advance the process of intelligent manufacturing. Accordingly, this article discusses the application status and development prospects of AI and industrial robots in the manufacturing industry.

In order to improve the accuracy and stability of the control system of mine fan, the control and frequency conversion speed regulation system of mine fan was developed based on PLC. Based on the analysis on control technology for mine fan, puts forward the inverter, soft start double mode control strategy, combined with the design of PLC control system hardware circuit and software program, the realization of mine fan starting and soft start, reasonable speed regulating, stop running process control, at the same time have the parameters such as voltage, current detection and fault protection function.

Landslide hazard investigation by using a standard geological survey in a mountainous terrain can result in low accuracy and poor update rate. These deficiencies could lead to unrecorded landslides, which could be catastrophic. Synthetic aperture radar interferometry (InSAR), which can detect subtle ground surface movements in large areas, is considered as a promising solution for detecting unrecorded landslides in mountainous terrains. To evaluate its feasibility, this study conducted analysis work and associated field survey in Fengjie County. The county is characterized by a mountainous terrain and is located in a notoriously landslide-prone area in the Three Gorges reservoir in China. A total of 30 SAR images captured by the Sentinel-1A satellite in 2018 were processed to obtain the ground surface movements of the county. InSAR results identified 276 anomalous regions that were not recorded in the local inventory map. Of these regions, 18 were verified as unrecorded landslides on the basis of the field survey. The observable deformation of the landslides recorded in the local inventory map was also detected by InSAR. This work, which is not supposed to diminish the importance of standard geological surveys, could improve the accuracy and update rate of local inventory maps.

The finite element analysis software ANSYS is used to analyze 9 reinforced concrete special-shaped columns under the combined action of axial force and torque. The parameters of the numerical model are given through repeated trial calculation. The influence of different values of axial compression ratio on the torsional capacity of test specimens is studied. The results show that the prediction error of the finite element model is small, which means the model is capable of accurate simulation. But the whole process analysis of the torque-torsion angle curve needs to be improved. The cracking and ultimate torque of special-shaped columns with different sizes and section shapes increase linearly with the growth of axial compression ratio. However when the ratio exceeds 0.6, the torsional bearing capacity of the columns will decrease. The increasing of axial compression ratio will also shorten the process from cracking to ultimate torque.

With the development of high-rise buildings, part of the frame structure is usually used to support the upper reinforced concrete shear wall, in order to form a large space. Thus a framed shear wall structure is formed. The shear force design value of the shear wall which is on top of the frame supported beam often exceeds limit value that a shear wall can bear during the construction design process. This does not meet the requirements of the current national code. A high-rise building with transfer story in 7 degree earthquake area is taken as an example to analyze the reason of shear wall over limit by using structural design software PKPM in this paper. Through numerical simulation analysis, it is concluded that the main reason for the shear force over limit is that the increase of constant load, which results in the increase of relative deformation of the frame supported beam and the shear wall, as well as the axial force of the coupling beam. Specific measures to reduce the shear force over limit are proposed by using a finite element analysis software MIDAS, which provides references for a structural engineer to carry out the design.

Recent advancements in bone implant materials have led to the development of various alloys. In this study, the degradation behavior of the as-cast Mg-3 wt% Zn-1 wt% Ca-0.5 wt% Sr alloy in vitro was investigated using x-ray diffraction (XRD), scanning Kelvin probe force microscopy (SKPFM), and scanning electron microscopy (SEM). Our results demonstrated that the alloy microstructure was composed of α-Mg, a Ca2Mg6Zn3 phase, and a Mg17Sr2 phase. The Ca2Mg6Zn3 phase, which had the smallest absolute potential, was shown to have cathodic protection, while the α-Mg, which had the largest absolute potential, was shown to prefer corrosion. The in vitro corrosion products of the as-cast alloy were Mg(OH)2, a Ca-P compound, and HA. At the beginning of the corrosion, the hydrogen evolution rate of the alloy was fast due to the thin corrosion product layer. With the extension of the corrosion time, the corrosion layer thickened and the hydrogen evolution rate slowed down and stabilized to 1.25 × 10−5 mol cm−2 · h . Due to the high concentration of Ca and Mg ions near the second phase, HA was quickly deposited and an ion exchange channel between the solution and the alloy was formed, making it easier for the Mg, Ca, and Sr ions to enter the solution and promote the formation of HA. The hysteresis effect of Sr element was found, that is, Sr ions were released into the solution after etching for a period of time, which promoted the formation of HA and HA-containing Sr (Sr/HA).

Using the national invention patent equipment, the proppant embedment experiment was carried out on the formation coal seam. The effects of proppant embedment on the conductivity of cracks under different proppant types, different proppant particle sizes, different sanding concentrations and different closing pressures were investigated. The experimental results show that with the increase of the closing pressure, the conductivity of quartz sand and ceramsite decreases rapidly; the conductivity of ceramsite is generally higher than that of quartz sand; the higher the concentration of sand, the proppant filling The stronger the layer’s compressive capacity and crushing resistance, the higher the fracture conductivity. XY ceramsite has the best conductivity.

This study reports a visible light-driven plasmonic photocatalyst of Au deposited AgVO3 nanocomposites prepared by a hydrothermal method, and further in situ modification of Au nanoparticles by a reducing agent of NaHSO3 in an aqueous solution at room temperature. Various characterization techniques, such as SEM, TEM, XRD, EDS, XPS, and Brunauer-Emmett-Teller, were used to reveal the morphology, composition, and related properties. The results show that belt-like AgVO3 nanoparticles with a width of ∼100 nm were successfully synthesized, and Au nanoparticles with controlled sizes (5-20 nm) were well distributed on the surface of the nanobelts. The UV-vis absorption spectra indicate that the decoration of Au nanoparticles can modulate the optical properties of the nanocomposites, namely, red shift occurs with the increase of Au content. The photocatalytic activities were measured by monitoring the degradation of Rhodamine B (RhB) with the presence of photocatalysts under visible light irradiation. The photodegradation results show that AgVO3 nanobelts exhibit good visible light photocatalytic activities with a degradation efficiency of 98% in 50 min and a reaction rate constant of 0.025 min-1 towards 30 ppm RhB. With the modification of Au nanoparticles, photocatalytic activity basically increases with the molar ratio of Au to V. Among the Au@AgVO3 nanocomposites, the 3% (molar ratio) Au decorated AgVO3 nanobelts showed the highest photocatalytic activity, and the k (0.064 min-1) was almost two times higher than that of the pure AgVO3 nanobelts. This can be attributed to several factors including specific surface areas, optical properties, and the energy band structure of the composites under visible light illumination. These findings may be useful for the practical use of visible light-driven photocatalysts with enhanced photocatalytic efficiencies for environmental remediation.

In the traditional optimization design of multi-stage fracturing in horizontal wells, the rock mechanics and stress profiles of the vetical section of horizontal well or other vertical wells near the perforated cluster are usually borrowed. In the strong heterogeneity reservoirs, there is a large deviation between the design results and the microseismic monitoring results. In this paper, based on the three dimensional geological model of reservoir, the stress and the rock mechanics parameter model are builded, the stress and rock parameters of vertical profile at each perforation center are extracted, we can evaluate the difficulty of fracture extending in different position, by adjusting the number of perforations to achieve the best stimulation effect.

We investigate the above-threshold ionization of an atom in a combined infrared (IR) and extreme ultraviolet (XUV) two-color laser field and focus on the role of XUV field in the high-order above-threshold ionization (HATI) process. It is demonstrated that, in stark contrast to previous studies, the XUV laser may play a significant role in atomic HATI process, and in particular, the XUV laser can accelerate the ionized electron in a quantized way during the collision between the electron and its parent ion. This process cannot be explained by the classical three-step model. Our results indicate that the previously well-established concept that HATI is an elastic recollision process is broken down.

Single crystalline (0001)ZnO films were grown by pulsed-laser deposition on (111) Si substrates containing thin Sc2O3 buffer layers (1 and 5nm) which were prepared by molecular-beam epitaxy at 700 ◦ C. Both x-ray diffraction and transmission electron microscopy reveal that the ZnO films grown at 240 and 400 ◦ C are highly crystalline with good epitaxy. The commonly seen amorphous SiOx layer has been successfully eliminated from the interface between the ZnO/Sc2O3 film and (111) Si substrate, resulting in improved electrical properties. Rectifying effects are observed in the heterojunction exhibiting a turn-on voltage of 1.08V and an ideality factor of 17.7. The room temperature mobility is 65cm 2 V −1 s −1 . A donor binding energy of 46.7meV is determined by temperature-dependent photoluminescence measurements.

A novel nanohybrid ratiometric fluorescence probe comprised of fluorescent graphene oxide and quantum dots (QDs) has been prepared by bringing CdTe QDs of red fluorescence and fluorescent graphene oxide (FGO) of blue fluorescence together through electrostatic attraction and hydrogen bonding interaction between their surface functional groups including carboxyl and amine groups. The nanohybrid ratiometric fluorescence probe exhibits dual emissions at 450 and 650 nm under a single excitation wavelength and shows high sensitivity for the detection of ferrous ions in the presence of H₂O₂. Ferrous ions reacts with H₂O₂ to generate very reactive hydroxyl radicals which possess a strong oxidizing nature and easily capture the electrons from the surfaces of the CdTe QDs, leading to fluorescence quenching of the QDs and no effect on the fluorescence of the graphene oxide, which hence results in a great change of the fluorescence ratio. Moreover, the ratiometric fluorescence probe is not only extremely sensitive to ferrous ions, but is also selective over other biologically relevant metal cations. The changes of fluorescence colour ratios can be used for visual sensing applications for ferrous ions in the presence of hydrogen peroxide, and can also be used for the indication of the existence of hydrogen peroxide.

Coaxial multi-layered structure is obtained when the Fe melt confined in the single-walled carbon nanotube (SWCNT) undergoes a rapid cooling. Owing to the inductive effect of the SWCNT, precursors of the long-range order (LRO) are generated in the confined Fe melt and finally been converted into local crystalline structures in the glassy Fe. A memory property has also been observed during the repeated phase transition process. Furthermore, the study of the size effect of tube diameter illustrates that the increasing diameter of the carbon tube is detrimental to the formation of local crystalline structures in nanoscale confinement.

We report the observation of periodical negative differential conductivity (NDC) in hydrogenated nanocrystalline silicon/crystalline silicon diode heterostructures by low-temperature current–voltage measurements. The NDC-related series of spike-like current peaks is found to result from the accumulation and depletion of electrons tunnelling through the nanodot layers in the neutral region. The observation has been further supported by the facts of onset-voltage blueshift, number variation in current peaks, and inter-Landau-level tunnelling in the temperature- and magnetic field-dependent experiments. We also discuss the differences between the present periodical NDC and the electric field domain in superlattice structures.

Investigations on broadband optical parametric amplification (OPA) are presented. Weak chirped-pulses are effectively amplified to milli-Joule level in short nonlinear crystals when pumped by frequency-doubled YAG lasers. The gain and spectral characteristics of chirped-pulse signals under different pumping conditions are analyzed.