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In this paper, industrial waste residue was used as the main cementing material instead of Portland cement to solidify the silt, which was in contrast with the single cement solidified silt. Firstly, the mechanical properties and influence laws of single cement and different mix ratio cement-industrial waste solidified silt were carried out. Secondly, the optimal mix ratio of solidified silt was obtained as: Portland cement: blast furnace slag: phosphogypsum = 3:6:1. Compared with the solidified silt with single cement, the compressive strength of the solidified silt with composite curing agent reached 517.19 kPa after curing for 28 days, which was 80.09% higher than that of the solidified silt with single cement. Finally, X-ray diffractometer (XRD), scanning electron microscope (SEM), thermogravimetric analyzer (TG) and nitrogen adsorption pore analyzer were used to study the composition, quantity, microstructure and pore characteristics of the minerals generated during the solidification process of the composite curing agent, so as to reveal the mechanism of the effective solidification of the silt by the composite curing agent. The test results showed that the secondary hydration reaction of blast furnace slag can be co-stimulated by the cement hydration products Calcium hydroxide and phosphogypsum, and the hydration products formed Hydrated calcium silicate colloid and Ettringite crystal. The hydration products with colloid properties were added to the solidified silt system, which will significantly improve the solidified silt performance of the composite curing agent. Hydrated calcium silicate colloid and Ettringite crystal played an important role in the skeleton and filling, and the structure of the silt solidified by the compound curing agent was more compact.

In this text, a method to use CO2 for the treatment of calcareous sand is presented. Carbon dioxide solidification-bacteria (Streptomyces microflavus) was obtained by screening and applied to the mechanical strengthening of calcareous sand through a microbial mineralization/carbonization process. Experiments in both liquid phase and sand were carried out. The optimal mass ratio of carbon dioxide solidification-bacteria to calcium oxide was found to be 2:1. The optimal dosage of bacterial powder was 30% of the total dry sand mass. Using the optimal recipe, the average uniaxial compressive strength of treated sand columns was 3.67 MPa and the average permeability coefficient was 4.90×10-3cm/s. Compared with the other microbial induced carbonate precipitation (MICP) approaches, the proposed method does not release harmful by-products such as ammonia. The chemical composition and microstructure of the treated calcareous sand were characterized by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The XRD results showed that the CO2 carbonized product contained mainly calcite.

Summary Effective medium rock physics model is the basis for the quantitative petrophysical interpretation of seismic and borehole acoustic measurements, because it links the formation petrophysical parameters with elastic properties, and the latter can be directly inferred from relevant measurements. Many existing works are based on conventional effective medium theories assuming isotropic underground formations, which may lead to erroneous estimates of formation properties. In this work, we extend the existing theories and develop a novel general anisotropic effective medium model to obtain the elastic constants of underground rocks. Three anisotropic effective medium theories are studied: self-consistent approximation (SCA), differential effective medium (DEM), and their combination. A newly extended Kuster-Toksöz (KT) model is also presented for the isotropic effective model. All these effective theories for elastic moduli are verified and validated with independent numerical results and experimental data. Then three workflows are implemented to obtain general stiffness coefficients for different formation models including the shaly sand model, the cracked sand model, and the shaly sand model with cracks. Furthermore, we also study the sensitivity of elastic moduli with respect to variations in pore aspect ratios.

This paper presents a stabilized nodal discontinuous Galerkin pseudospectral time domain (DG-PSTD) algorithm for fully anisotropic electromagnetic waves. This solver permits arbitrary high-order basis functions and adaptive hexahedral elements, thus very efficient for large-scale wave propagation in complex media. Maxwell’s equations are reformulated in a unified hyperbolic form, where a localized anisotropic Riemann solver is derived to serve as a numerical flux to exchange information across adjacent elements in the DG-PSTD scheme. This local analysis method also helps impose the time-domain anisotropic plane wave incidence in the total/scattering field framework. Numerical validations and applications demonstrate the efficiency, accuracy, and capability of this new high-order solver for 3-D large-scale generally anisotropic electromagnetic media.

Thin dielectric or conductive structures are very common in many applications. Modeling such structures in the finite element method can require a very dense mesh near the structures, which increases the computation cost and degrades the mesh quality. In this work, the surface current boundary condition is incorporated into the framework of the spectral-element spectral-integral method to efficiently model thin structures with double periodicity embedded in layered media. The thin structures are viewed as zero-thickness surfaces, and no dense mesh is required. Furthermore, a fast and convenient formulation is developed to evaluate the tangential field in the background of doubly periodic structures. Numerical experiments demonstrate the accuracy and efficiency of the proposed method by comparing with various reference solvers.

As one of the most widely used building materials, concrete consumed a lot of raw materials, and the comprehensive utilization of waste concrete had become a research hotspot. Firstly, the basic properties of recycled aggregate were studied, including crushing index, water absorption, apparent density and bulk density. The higher the amount of microorganism, the greater the basic properties. Secondly, the porosity of recycled aggregate was analyzed by MIP. With different microbial dosage, the decrease range of porosity was also different, and the decrease ranges were 15.87%, 27.74%, 31.98%, 32.19% and 35.10% respectively. Finally, the composition and microstructure of recycled aggregate were demonstrated by XRD, SEM and EDS. The results showed that mineralized product was calcium carbonate, and the surface layer of recycled aggregate formed a dense structure.

As a green and environmental protection method, the self-repairing technology has great expectations to be met. In this study, the influence of ettringite on the crack self-repairing of cement-based materials in a hydraulic environment was systematically analyzed. First, the composition and pore characteristics of the self-repairing carrier was studied by XRD, XRF, and the mercury injection method. The composition was basically consistent with cement-based materials, and the structure of the self-repairing carrier was relatively dense. Second, the products were analyzed by SEM and EDS, and it was found that the distribution range of crystal size was from 1 to 20 µm, the cube and flocculent accumulation was calcite, while the rod and flake crystals were ettringite. Finally, the repair effect on the surface and inside of the crack was demonstrated by the crack area repair rate and water permeability resistance. Compared with single microbial mineralization, the synergistic repair effect of microbial mineralization and ettringite formation was better in water permeability resistance. With the further increase of water pressure, its advantages would be more obvious.

The long-term properties of solidified soft soil, including an immersion test, the dry–wet cycle and the freeze–thaw cycle, were systematically studied. Firstly, the immersion stability of solidified soft soil was confirmed. The appearance of soft soil solidified by a solidified agent and raw fine aggregate did not change significantly, and it was still intact without damage when the soaking time increased up to 28 d. Secondly, the mass and compressive strength loss of solidified soft soil were determined. When the number of dry–wet cycles was one, three, five and seven, the accumulated-mass loss rate was 1.4%, 3.0%, 4.5% and 6.0%, respectively, and the compressive-strength loss rate was −10.3%, 13.9%, 41.2% and 53.6%, respectively. Compared with solidified soft soil under standard curing environments, solidified soft soil after seven dry–wet cycles showed small cracks, and the structural compactness began to decline. Finally, the influence of the freeze–thaw cycle on the mass, compressive strength and microstructure of solidified soft soil was confirmed. When the number of freeze–thaw cycles was 5, 10, 15 and 20, the accumulated-mass loss rate was 12.6%, 16.7%, 17.9% and 18.8%, respectively. The microstructure of the solidified soft soil was damaged, and the increase in porosity was the main reason for its strength reduction or even failure. Nevertheless, soft soil with a solidified agent and recycled fine aggregate had no obvious damage to the microstructure, and the freeze–thaw resistance was relatively superior.

The solidification property and mechanism of soft soil based on the industrial waste residue was studied systematically. First, the properties of soft soil solidified by single blast furnace slag, phosphogypsum and cement were carried out, and the solidification effect of Portland cement was better compared with blast furnace slag and phosphogypsum. Second, the composite solidification agent formula with excellent solidification performance was developed, and the mass ratio of Portland cement, blast furnace slag and phosphogypsum was 1:2.3:0.8. At this time, compressive strength was up to 8845.1 kPa. Finally, the composition and microstructure of the solidification soft soil was studied by X-ray diffractometer and scanning electron microscope. Calcium hydroxide formed by the hydration of Portland cement and calcium sulfate in phosphogypsum were used as activators for hydration reaction of blast furnace slag, and more hydration products under the synergistic action of Portland cement hydration and blast furnace slag hydration were formed. Hydrated calcium silicate colloid and Ettringite crystal played an important role in skeleton and filling, and the structure of soft soil solidified by composite solidification agent was the most compact.

In recent years, China's economy has rapid development and maintained stable, and the lives of our residents have been well improved. With the growth of the income level of our residents, the consumption level has also been continuously improved, and the overall quality of life has been improved; the rich groups in China are constantly developing and expanding, and the scale of high-asset net worth people is also expanding, which has become one of the reasons why more and more people pursuing luxury goods. In the consumer group that consumes luxury goods, it dominates Generation Y and Z, becoming the main market for luxury goods consumption. Young-generation has become a new pet for luxury goods and uses traditional luxury goods as a "social status symbol, showing off identity” is gradually reversed to the concept of "own personalized enjoyment and self-worth manifestation". This article will investigate the motives and effects of university students’ luxury consumption through quantitative analysis of questionnaires.

An efficient multiconductor transmission line (MTL) model of a shielded twisted wire pair (TWP) with apertures on its sheath is developed for predicting common mode (CM) and differential mode (DM) currents induced in the shielded TWP cable. Its transfer impedance and admittance with one-line apertures on its sheath are derived in a closed form. Therefore, the MTL equations are formulated and solved to obtain the CM and DM currents induced in the shielded TWP. Moreover, the proposed MTL model is generalized to be applicable for the braided–shielded TWP, in which the transfer impedance and admittance are formulated analytically. Results showed that the induced DM current inside the braided–shielded TWP is suppressed dramatically due to the uniform structure of the cable. The models are validated by comparing their results with those obtained by the commercial software FEKO; good agreements are obtained.

In this paper, a large-scale electromagnetic-thermal-mechanical co-simulation solver is implemented for simulating complex radio frequency components by using a high performance computing framework. The proposed solver integrates the frequency-domain electric field simulation, with time-domain thermal and thermal induced stress simulations, via a multiphysics coupling iterative process. In order to speed up the co-simulation, a Krylov subspace method with a domain decomposition method (DDM) preconditioner is used. First, the developed multiphysics solver is verified with the commercial software COMSOL Multiphysics. Then, the parallel performance of our co-simulation solver, with different ghost mesh thicknesses, is tested on a supercomputer. Finally, some multiphysics results of filters and a real-world system-in-package (SiP) are obtained with our proposed solver.

This article presents an efficient analytic algorithm to calculate the electromagnetic (EM) fields radiated from orthogonal magnetic and electric dipoles in the fully anisotropic planar-stratified media. The EM fields are transformed into the frequency–wavenumber domain by the double Fourier transform, which yields a set of ordinary differential equations, consisting of a system matrix, a field vector, and a source vector. The eigenvalues of the system matrix are uniquely determined, but the corresponding eigenvectors can be multiplied by an arbitrary constant or be normalized by energy. With these eigenvalues and eigenvectors, the field vectors are expressed as mode fields consisting of the up-going and down-going fields. The propagation of the mode fields in each layer is described by the generalized reflection/transmission method. To accelerate the evaluation of the inverse Fourier transform of EM field from spectral domain to spatial domain, an approximated primary field was subtracted from total field. Numerical results from a finite element method (FEM) validate the proposed method. Then, we apply this new algorithm to a variety of real applications in geophysical prospecting.

The influence of recycled fine aggregate content on the properties of soft soil solidified by industrial waste residue was systematically studied. First, the addition of recycled fine aggregate may provide skeleton support, which was conducive to improving the solidification properties. Comparing the addition of recycled fine aggregate content and a composite solidification agent separately, the compressive strength increased 48.01 times and 1.32 times, respectively. Second, the composition and quantity of the hydration products were analyzed by X-ray diffraction (XRD) and thermal gravity analysis (TG/DTG). In addition to silicon dioxide and aluminum oxide, a number of new minerals, including hydrated calcium silicate, calcium hydroxide and ettringite, were produced under different recycled fine aggregate contents. The diffraction peak of hydrated calcium hydroxide was weak, which indicated that the crystallinity and relative content was low. The main reason for this was that it was consumed as the activator of the secondary hydration reaction of blast furnace slag. With the increase in recycled fine aggregate content, the total weight loss (hydration products, crystal water, impurities) increased significantly, at rates of 6.9%, 7.0%, 7.2%, 8.8% and 9.7%. The addition of recycled fine aggregate does not change the composition and quantity of the hydration products, and the increased weight loss in this part might be caused by the cement paste attached to the surface of the recycled fine aggregate. Finally, their microstructure was analyzed by scanning electron microscopy (SEM). Larger and more pores appeared in the solidification system with the increase in recycled fine aggregate, and a large amount of ettringite was prepared. An excess in recycled fine aggregate caused more pores, and the negative impact of too many pores exceeded the lifting effect of the aggregate, resulting in the decline of its mechanical properties. Therefore, there was a suitable range for the use of recycled fine aggregate, which was not more than 40%. In conclusion, recycled fine aggregate not only acts as a skeleton to improve solidification strength, but could also realize the comprehensive utilization of waste, which provided a new scheme for solid waste utilization and soft soil solidification.

The simulation of electromagnetic fields in many applications with double periodicity can be viewed as an image-to-image translation problem, where the structure is known and the fields need to be predicted. In this work, we take extreme ultraviolet (EUV) lithography as an example and propose a very efficient technique based on the U-Net architecture, a deep fully convolutional network (FCN). The U-Net is trained with data of some typical patterns in a 128 nm $\times\,\,128$ nm unit cell, and good accuracy can be obtained in the prediction of the near field on much larger unit cells with complex patterns. Furthermore, numerical experiments demonstrate that the proposed method is three orders of magnitude faster than conventional state-of-the-art methods, such as the spectral-element spectral-integral method.

Microbial-induced degradation of aromatic organic compounds and mineralization of zinc ions have attracted much attention because of its low cost, simple operation and quick response. This research, toluene was decomposed and made the concentration of carbonate ions increased accordingly by the enzymatic pressing of microorganisms, meanwhile carbonate ions mineralized zinc ions into carbonate precipitations. The composition and microstructure were analyzed systematically. The analysis results indicated that carbonate precipitations, basic zinc carbonate, could be successfully prepared by microbial method. The particle size of basic zinc carbonate was nanometer, and its shape was near-spherical. Furthermore, the phase composition, functional groups and surface morphology of the precipitations prepared by different methods were basically the same. This work provided a new method for remediation of zinc ion pollution based on the degradation of toluene.