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This paper proposes analytical solutions for the resonant radiation performance of bending-mode magnetoelectric (ME) antennas. The strain-mediated Converse ME (CME) coupling model of bending-mode ME antennas is first established by solving nonlinear constitutive equations and bending governing equations using the elastic mechanics method. Then, the calculated magnetic flux and electric displacement are employed to propose a resonant radiation field model based on the dipole method. The numerical results for the CME coefficient show a good agreement with the experimental data. It can be observed that the volume fraction ratio of the piezoelectric layer can control the CME coefficient and radiation efficiency with the same variation trend since it can determine the bending strain via changing the location of the neutral layer of the ME antennas, which also demonstrates the strain-mediated essence of the ME antennas. In addition, the volume fraction ratio can tune the resonant frequency within a wide range. The gain of the ME antenna is stable and higher than −168 dB with the volume fraction ratio ranging from 0.2 to 0.7. The tensile stress and compressive stress have the opposite effect on the resonant frequency at low and high bias magnetic fields. Meanwhile, the tensile (compressive) stress is beneficial for both the radiation and gain in the low (high) bias field region. This model may facilitate the understanding of the bending-mode radiation mechanism of ME antennas and provide a basis for designing asymmetric ME antennas. [ABSTRACT FROM AUTHOR]

Hybrid nanofluids were expressed by heat-transfer fluids into greater surface dispersion capabilities, stability and diffusion related for traditional nanofluids. The effort on the flow of volumetric entropy generation and convective heat transport of MHD hybrid nanofluid is considered. Hybrid nanofluid involves the field over the orderly stretchable surface for variable heat flux with the resistance of electric field. Effect on convective heating and nonlinear thermal radiation is again contained in the interpreted figure. Mathematical equations such as momentum, energy, conservation of mass and entropy were collected as conversion to governing partial differential equations by ordinary differential equations, utilizing similarity variables. An efficient finite element method (FEM) is used. Numerical calculations were accomplished for silver–magnesium oxide water (Ag-MgO/H2O) hybrid nanofluid and conventional silver water (Ag-H2O) nanofluid. The graphs were created by the temperature, velocity, and entropy profiles. to analyse the impact on governing parameters. These skin friction and heat transfer rates are analysed through regression analysis. The important allegation expressed by the hybrid Nanofluid has the best heat transfer rate, which is related to convectional nanofluid. Further, It raised the Brinkman number and Reynolds number and developed a total entropy of the structure. [ABSTRACT FROM AUTHOR]

Waste concrete is a large amount of solid waste produced in the process of urban construction and renewal in China. Its resource utilization is of great significance for saving mineral resources and improving urban environmental quality. The present study was designed to investigate the effects of mechanical grinding time on the particle size distribution and activity of recycled waste concrete powder (RWCP). Combined with unconfined compressive strength, slump, electric flux and chloride ion penetration resistance tests, the effects of RWCP on the mechanical properties, working performance and impermeability of concrete were analyzed, and the phase and microstructure of concrete containing RWCP were analyzed by XRD and SEM. The results showed that the RWCP is mainly composed of quartz, gismondine, C2S, cancrinite and portlandite. The optimum activity of RWCP obtained by ball milling for 45 min was 44.41%. RWCP can improve the fluidity of concrete and shorten the initial setting time of concrete. When the blast furnace slag in the concrete was replaced by the RWCP, the early strength and impermeability of the concrete decreased. When RWCP replaced blast furnace slag by 69.1%, the UCS of the concrete at 1, 3, 7, and 14 d decreased from 9.56, 22.1, 34.1, and 41.2 MPa to 5.9, 14.5, 22.7, and 33.2 MPa, respectively. While RWCP replaced fly ash, the normal strength of concrete increased with the increase in fly ash replacement amount. When RWCP completely replaced FA in concrete, the 28-day strength of the concrete increased from 45.2 MPa to 50.8 MPa. The impermeability results showed that the appropriate substitution of RWCP for fly ash was beneficial to increase the impermeability of concrete while excessive substitution reduced. Based on these results, the RWCP has the potential for large-scale application in the preparation of concrete. [ABSTRACT FROM AUTHOR]

Advanced aqueous zinc-ion batteries have been greatly limited application caused by uncontrollable dendrite formation, hydrogen evolution and zinc metal corrosion, which can lead to quick failure of the battery and low Coulombic efficiency. Three-dimensional (3D) porous host strategy is available to limit zinc dendrite growth and electrode interfacial side reactions. Herein, an ingenious local levelling and macro stereo strategy is rationally designed as a Zn plating/stripping scaffold. The flexible 3D carbon cloth as the structural and conductive framework is coated by Ag-Cu-reduced graphene oxide (Ag-Cu-rGO) and Ketjen black. Benefiting from the uniformly dispersed zincophilic Ag on the surface of Cu nanoboxes, the anode suppresses hydrogen evolution side reactions and reduces local current density via more nucleation sites. In addition, rGO homogenizes both the ion flux and electric field at the electrode surface, resulting from high conductivity and large specific surface area of rGO. As a result, the fabricated Zn//Ag-Cu-rGO asymmetric cells exhibit stable voltage profiles for plating and striping 250 cycles, maintain nearly 100% Coulombic efficiency at 2 mA·cm−2 and 1 mAh·cm−2 as well as behave an extremely small nucleation overpotential of 34 mV and Ag-Cu-rGO@Zn symmetric cell presents highly uniform electric field with a superior lifespan over 2500 h at 1 mA·cm−2 and 1 mAh·cm−2, respectively. Meanwhile, this efficient Ag-Cu-rGO@Zn anode also enables a substantially stable Ag-Cu-rGO@Zn//V2O3 full cell over 2000 cycles. The work opens a new avenue of 3D host for durable and dendrite-free flexible aqueous zinc-ion batteries anode. [ABSTRACT FROM AUTHOR]

The effects of nano‐SiO2 and hydroxypropyl methyl cellulose (HPMC) on the physical and mechanical properties of magnesium phosphate cement (MPC)‐based mortar under salt corrosion environment were studied. The variation of strength under salt corrosion environment was compared and studied. The chloride ion permeability of modified MPC mortar was evaluated by electric flux method. X‐ray diffraction (XRD) and scanning electron microscopy (SEM) were used to observe the composition and morphology of the samples under salt corrosion environment. Results showed that appropriate amount of nano‐SiO2 can significantly improve the compressive strength, flexural strength, and chloride ion penetration resistance of MPC‐based mortar under 3% NaCl solution corrosion. There existed an optimal dosage. The incorporation of HPMC would significantly reduce the compressive and flexural strength and the resistance to chloride ion penetration of MPC‐based mortar. Appropriate amount of nano‐silica and HPMC could improve the bonding performance of modified MPC‐based mortar under salt corrosion environment. [ABSTRACT FROM AUTHOR]

With the rise of eco-friendly policies, advanced motor technologies are being developed to replace fossil fuel-based engines in the mobility industry. Axial flux motors, known for their ability to reduce size and increase output torque compared to radial flux motors, require different materials and manufacturing techniques. Specifically, the production of complex stator cores and segmented magnets presents significant challenges, often leading to higher costs. To address this issue, soft magnetic composite (SMC) materials, which offer greater design flexibility, are being explored for use in stator cores. However, soft magnetic composite materials exhibit lower permeability and saturation flux density compared to laminated silicon steel, resulting in reduced output torque and efficiency. This paper investigates the effects of stator geometry on axial flux motor performance and explores cladding core technology, which combines soft magnetic composite materials with silicon steel. By conducting finite element method (FEM) analysis to evaluate the output torque and efficiency based on the shape of the silicon steel within the cladding core, this study proposes an optimized cladding core design to enhance the efficiency and output torque of axial flux motors. [ABSTRACT FROM AUTHOR]

Switched reluctance motors (SRMs) are highly advantageous electric motors for various industrial applications, particularly in electric vehicles (EVs), due to their winding-free rotor, magnet-free design, simplicity, and ease of manufacturing. The growing interest in axial flux SRMs (AFSRMs) is particularly noticeable, as axial flux electric motors with a flat shape and high aspect ratio have become commonly used in various industrial applications, including in-wheel motors for EVs. Structurally, AFSRMs significantly differ from radial flux SRMs (RFSRMs), but share the same electromagnetic operating principles. When compared to RFSRMs, AFSRMs generate higher torque per unit volume due to their more effective utilization of their air gap. In this study, the axial force on the rotor and torque ripple of a 6/4 pole fully pitched axial flux SRM (FP-AFSRM) were minimized by combining the advantages of "single-stator and single-rotor AFSRM" and "double-stator and single-rotor AFSRM" models. The proposed FP-AFSRM model, which has a "double-stator and single-rotor AFSRM" design and has the operating logic of a "single-stator and single-rotor AFSRM", was analyzed using 3D finite element analysis. The results show that the torque ripple decreased (Δ % Trip) between (−30.42) and (−41.14), and the axial force on the rotor decreased between 17.61% and 25.4%. [ABSTRACT FROM AUTHOR]

Achieving reversible plating/stripping of zinc (Zn) anodes is crucial in aqueous Zn‐ion batteries (AZIBs). However, undesired dendrite growth and parasitic side reactions severely deteriorate battery lifespan. The construction of stable protective coating is an effective strategy to enhance anode stability. In this study, a multifunctional nanodiamond (ND) inorganic layer is designed and constructed on both Zn and Cu electrodes that can both effectively inhibit dendrite growth and suppress Zn anode corrosion. Experimental results and theoretical calculations demonstrate that this artificial protective layer, with ultra‐high surface energy, enables the controlled creation of abundant nucleation sites (in the order of 1012 cm−2) for the homogenization of ion flux and electric field on the anode. It is found that zinc ions preferentially adhere to the diamond surfaces with lower diffusion barriers, leading to uniform zinc deposition. A symmetric cell with the ND‐protected Zn (Zn‐ND) anode exhibits reversible plating/stripping behavior for an impressive duration of over 3600 h at 1 mA cm−2. Furthermore, the MnO2||Zn full battery retains 90% of its initial capacity after 3500 cycles at 2 A g−1, and assembled hybrid capacitor operates smoothly over 65 000 cycles at 10 A g−1. These results underscore the potential of this coating as a promising solution for achieving highly stable Zn anodes for aqueous batteries. [ABSTRACT FROM AUTHOR]

A bimaterial piezoelectric space with collinear electrically limited permeable cracks along the material's interface is considered under plane strain conditions. The distances between the cracks, their location and number can be arbitrary. The problem of linear relationship is formulated and solved exactly. The electric flux over the crack regions is found. The closed-form expressions for stresses and electric displacement outside cracks and also for displacement jumps over cracks regions are found. The energy release rates at the crack tips are also derived in an analytical form. Numerical analysis is performed for different loading, cracks permittivity, their number, lengths, and locations. [ABSTRACT FROM AUTHOR]

AbstractThis study investigates the flow of an incompressible electroosmotic hybrid nanofluid through a micro-channel. The hybrid nanofluid consists of paramagnetic (Ta) and ferrimagnetic (Fe3O4) nanoparticles suspended in ethylene glycol. The Darcy model is applied to the porous media in the momentum equation, and its effects are also considered in the temperature equation, accounting for frictional and Joule heating effects. The micro-channel is influenced by both pressure and magnetic flux. The study derives an exact solution for the proposed model and evaluates key engineering parameters, such as the heat transfer rate. The findings show that a higher particle volume fraction reduces the velocity distribution, while an increased Darcy parameter decreases the rate of heat transfer. Additionally, the heat transfer rate diminishes with increasing Darcy parameter and electric flux. Notably, the ferrimagnetic nanofluid exhibits better thermal conductivity than the paramagnetic nanofluid. [ABSTRACT FROM AUTHOR]

In this manuscript, we illustrate antiferromagnetic geometric electric Heisenberg-microfluidical axially mKdV r -electrical ϕ (r) , ϕ t , ϕ n flux solidity in spherical Heisenberg group. Then, we get optical electric Heisenberg-microfluidical mKdV r -magnetomotive ϕ (r) , ϕ t , ϕ n phase. Also, we obtain antiferromagnetic axially electrical Heisenberg-microfluidical mKdV r -electrical ϕ (r) , ϕ t , ϕ n flux r -direction orbit in spherical Heisenberg group. Finally, we have antiferromagnetic optical electric Heisenberg-microfluidical mKdV r -magnetomotive ϕ (r) , ϕ t , ϕ n phase. [ABSTRACT FROM AUTHOR]

An injector nozzle needs a precision upside-down tapered-microhole, and the nozzle material is often a high temperature corrosion resistant alloy that is very difficult to machine. In this study, a same-spot micro-ECM technique with the electrode in "constant-accelerated movement" was proposed. Insulated by electrophoretic deposition, an ultra-fine electrode was inserted deep into the hole and subject gradually to withdrawal from the hole at constant rpm and acceleration. The electric flux intensity acting on the hole-wall gradually decreased and so did the material dissolution rate on the hole-wall, thus creating an upside-down tapered hole with the desired taper-rate. The experiments' results showed that upside-down tapered holes with taper-rates of T(a=1) = 0.094 (Ra 0.593 μm) and T(a = 2) = 0.02 (Ra 0.435 μm) were produced when the electrode was subject to constant-acceleration withdrawal at 1.0 and 2.0 μm/s2, respectively, and respective spray angles of 31° and 23° were created. The proposed technique is commercially promising in industry. [ABSTRACT FROM AUTHOR]

This paper proposes a method of enhancing public filler (PF) with nano-SiO2 (NS) to prepare modified recycled aggregate mortar (RAM). The improvement effect of NS solution at different concentrations and immersion times on the macroscopic physical properties of recycled public fine aggregates (PFA) was investigated. Moreover, the effect of NS on the basic physical properties and durability of recycled mortar (RM) and the reinforcement mechanism of NS on recycled mortar was analyzed through various techniques. Results indicated that the modification effect of NS could remove loose cement mortar from the surface of PFA. It reacted with calcium hydroxide and calcite to generate nano-particles that could fill pores in PFA. The water absorption rate of PFA decreased to 9.3% when immersed in 2% NS solution for 72 h. There was no significant improvement in the mechanical properties of RM when the solution concentration and immersion time were increased. However, the compressive strength of RM prepared by modifying PFA with 2% NS was increased by about 21.9%, and the capillary water absorption and electric flux were reduced by 56.3% and 15.1%, respectively. Micro-analysis results showed that the volcanic ash effect of NS enabled it to react with Ca(OH)2 adhered to the surface of PFA, generating C-S-H and improving the interfacial bonding of PFA. Moreover, NS adsorbed on the surface of PFA dispersed into the freshly mixed cement slurry, which further enhanced the internal structure of PFA. [ABSTRACT FROM AUTHOR]

A statistical study has been made of dynamic small‐scale auroral events in order to understand the drivers of the large variability in the electrodynamics of auroral arcs at fine scales. We used the Auroral Structure and Kinetics (ASK) instrument, located on Svalbard, in order to measure various electrodynamic properties of fine scale auroral arcs. We performed Spearman and Kendall statistical tests and found two significant correlations. The first is between the mean precipitation flux and the variability of flux, which we assume is because of the dynamic and bursty nature of the acceleration mechanism and its dependence on Alfvén waves. The second correlation is between the variability of the precipitating electron flux and the variability of the tangential component of the electric field close to the arc and perpendicular to the magnetic field. We propose that both variabilities occur because of the variability of the upward (field‐aligned) current sheet in and around the arc, which is dynamic and non‐uniform. The correlation between the two variabilities can therefore be explained by their common source. Key Points: We report a statistical analysis of small scale electrodynamics, to better understand the drivers of small scale variabilityThere is a significant correlation between average flux and variability of the flux in our eventsThere is a significant correlation between variability of tangential component of the electric field and variability in fluxWe propose that variability of the dynamic non‐uniform field aligned current sheet would be a source of variability in both electric fields and in flux, causing them to be correlated [ABSTRACT FROM AUTHOR]

This paper discusses the construction and operating principle of an axial flux electric machine with hybrid excitation. Based on computer simulations using the Finite Element Method, an analysis was conducted with changes in the geometry of the magnetic circuit, which involves the rotation of the rotor disks relative to each other on the operating parameters of the machine. Both the generator state of operation, in the meaning of analyzing the induced voltage (adjustment at −11% ÷ +64%) and the cogging torque, and the motor state of operation, in the meaning of analyzing the ripple of the electromagnetic torque (possible reduction by almost 30%), were examined. The article concludes with observations on how the change in the angle of the rotor disks affects the efficiency of the disk machine with axial flux and hybrid excitation. [ABSTRACT FROM AUTHOR]

In the transportation industry, the use of renewable energies has been implemented in conjunction with the development of higher-power electric motors and, consequently, the development of intelligent control systems for torque and speed control. Currently, the coupling between both systems is being developed through mechanical systems, affecting the efficient transmission of energy and the useful life of the components. On the other hand, new configurations of electric motors are being developed, such as axial flux motors (AFM), because these can be coupled directly without a mechanical coupling, given their characteristics of high torque at low speeds. In the present work, an innovative design of a multipole axial flux motor (MAFM) is introduced. General criteria for the design and construction are presented considering the geometry in axial flux and permanent magnets. The performance of the system is evaluated through finite element magnetic simulations (FEMM) and compared with experimental measurements of the developed prototype; confirming the effectiveness of the design, obtaining torques of up to 1.784 Nm without extra mechanical couplings and maximum speed regulation errors of 8.43%. The motor was controlled by a digital pole switching system whit six control mode, applied to a permanent magnet MFA for speed and torque control at constant speed. This control can be extended to conventional radial flux electric motor configurations and intelligent traction applications, based on torque demand. [ABSTRACT FROM AUTHOR]

This study employed the rapid chloride ion penetration test and the salt spray erosion method to examine electric flux changes in mineral-admixed reactive powder concrete (RPC). Variations in the chloride ion content and diffusion coefficient under different erosion durations and depths were also investigated. The impact of mineral admixtures on the chloride penetration resistance was explored. Notably, after mixing fly ash (FA) and granulated blast furnace slag (GGBS), the electric flux values of RPC of each group were significantly reduced, and the electric flux values of RPC of the mixed group were significantly lower than those of the single mixed group and the reference group, in which the electric flux of FA10G10 was reduced by 85.2% compared to the control group; at the same erosion cycle and depth, the chloride ion content and diffusion coefficient of the mixed group were significantly lower than the control group. It shows that the reasonable compounding of mineral admixtures can better exert the "superposition effect", improve the compactness inside the matrix, and effectively reduce the chloride ion penetration rate. Considering comprehensively, the FA10G10 group has the best chloride penetration ion resistance effect.

Purpose – During the construction process of the China Railway Track System (CRTS) I type filling layer, the nonwoven fabric bags have been used as grouting templates for cement asphalt (CA) emulsified mortar. The porous structure of nonwoven fabrics endowed the templates with breathability and water permeability. The standard requires that the volume expansion rate of CA mortar must be controlled within 1%–3%, which can generate expansion pressure to ensure that the cavities under track slabs are filled fully. However, the expansion pressure caused some of the water to seep out from the periphery of the filling bag, and it would affect the actual mix proportion of CA mortar. The differences in physical and mechanical properties between the CA mortar under track slabs and the CA mortar formed in the laboratory were studied in this paper. The relevant results could provide important methods for the research of filling layer materials for CRTS I type and other types of ballastless tracks in China. Design/methodology/approach – During the inspection of filling layer, the samples of CA mortar from different working conditions and raw materials were taken by uncovering the track slabs and drilling cores. The physical and mechanical properties of CA mortar under the filling layer of the slab were systematically analyzed by testing the electrical flux, compressive strength and density of mortar in different parts of the filling layer. Findings – In this paper, the electric flux, the physical properties and mechanical properties of different parts of CA mortar under the track slab were investigated. The results showed that the density, electric flux and compressive strength of CA mortar were affected by the composition of raw materials for dry powders and different parts of the filling layer. In addition, the electrical flux of CA mortar gradually decreased within 90 days’ age. The electrical flux of samples with the thickness of 54 mm was lower than 500 C. Therefore, the impermeability and durability of CA mortar could be improved by increasing the thickness of filling layer. Besides, the results showed that the compressive strength of CA mortar increased, while the density and electric flux decreased gradually, with the prolongation of hardening time. Originality/value – During 90 days' age, the electrical flux of the CA mortar gradually decreased with the increase of specimen thickness and the electrical flux of the specimens with the thickness of 54 mm was lower than 500 C. The impermeability and durability of the CA mortar could be improved by increasing the thickness of filling layer. The proposed method can provide reference for the further development and improvement of CRTS I and CRTS II type ballastless track in China.

Garnet solid state electrolytes (SSEs) have emerged as propitious candidates for solid‐state batteries (SSBs) with exceptional ionic conductivity and excellent (electro)chemical stability. However, the Li|garnet interface contact deterioration still remains a major challenge resulting in Li dendrite propagation. Herein, a method is proposed to strengthen the adhesion of garnet SSE and Li by incorporating Sr3N2 into the Li metal. Density functional theory (DFT) calculations reveal that the interfacial formation energy of Li|garnet is decreased by the obtained Li‐Sr‐N (LSN) composite, which can enable a shift from poor contact to intimate bonding at the Li|garnet interface and a homogenous Li+ flux as well as electric field distribution. Simultaneously, the produced Li3N and LiSrN, which are known for their strong Li adsorption affinity and rapid Li+ transfer kinetics, actively govern the Li plating process. Thereby this rational design brings a notable reduction in interfacial impedance (4.5 Ω cm2), along with the increased critical current density (1.3 mA cm−2) and enhanced cycle stability (1200 h at 0.3 mA cm−2). Furthermore, The LFP|garnet|LSN full cell has demonstrated remarkable cycling performance (95.9% capacity retention after 200 cycles at 1 C) and favorable rate capability (150.2 mAh g−1 at 0.1 C and 134.9 mAh g−1 at 1 C). The research provides a new sight into lithium modification that can restrain Li|garnet interface deterioration and lay the groundwork for future advancements in high‐performance garnet‐ based SSBs. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To investigate the influence of material factors on the properties of basalt fiber-reinforced pavement concrete (BFRPC), orthogonal test was designed to test the strength, impermeability, and frost resistance of BFRPC. The change trend of properties with various factors was analyzed, and the reasonable dosage ranges were recommended. The results show that the content of basalt fiber and fly ash is the main factor affecting the compressive strength, while the principal elements affecting flexural strength are the content and length of basalt fiber. The electric flux of BFRPC increases 9.6–11.2% with the rise of fiber length, but the impermeability can be improved by adding fly ash. Basalt fiber and superplasticizer are beneficial to improve the frost resistance. Basalt fiber with 12 mm are recommended for use in pavement concrete with a content of 0.06–0.08%, and the dosage of fly ash and superplasticizer is 20 and 0.8–0.9%. [ABSTRACT FROM AUTHOR]

This research is focused on the examination of an unsteady flow of an electromagnetic nanofluid close to a stagnation point over an expanded sheet kept horizontally. Buongiorno's nanofluid model is revised with the combined influence of the externally applied electric and magnetic fluxes. Moreover, the underneath surface offers multiple slips into the nanofluid flow. The leading partial differential equations (PDE) are renovated to the nonlinear ordinary differential equations (ODE) with the assistance of similarity transformations. Thus, the outcomes are received numerically by using the RK-6 with Nachtsheim–Swigert shooting technique. The enlistment of the outcomes for the momentum, energy and concentration profiles along with the skin-friction coefficient (C f x ∗) , Nusselt number (Nu x ∗) and Sherwood number (Sh x ∗) for several parametric values are presented in a graphical and tabular form and discussed in detail. The variation of streamlines with respect to the unsteadiness parameter is also recorded. Statistical inspection reveals that the flow parameters are highly correlated with the wall shear stress, wall heat and mass fluxes. Findings indicate that the escalation of electric flux tries to intensify the hydrodynamic boundary layer meanwhile the magnetic flux assists to stabilize the growth by reducing it for both the steady and unsteady flow patterns. Influence of velocity slip parameter ξ from 0.0 to 1.5 causes the reduction in Nu x ∗ by 16.98% for steady flow while 60.27% for time-dependent flow case. Moreover, we expect that these theoretical findings are very much helpful for several engineering and industrial applications such as polymer sheet productions, manufacturing automobile machines, cooling microelectronic chips, etc. [ABSTRACT FROM AUTHOR]

In this article, we illustrate surface flow a l f a - microfluidical mKdV spherical electromotive phase in sphere space. Also, we obtain antiferromagnetic axially electrical a l f a - microfluidical mKdV electric flux path circuit. We have electrical a l f a - microfluidical geometrical mKdV free surface flow density in sphere space. Finally, we design antiferromagnetic wave propagation for a l f a - microfluidical geometric mKdV surface flux density. [ABSTRACT FROM AUTHOR]

The present work concerns microchannel fabrication using magnetic-assisted electrochemical discharge machining on silica glass. The magnetic field regulates the process by controlling bubble formation and separation adjacent to the tool edge. Due to the applied magnetic and electric flux on the electrolyte and electrode interface, the Lorentz force impacts the bubble establishment and film quality. The fractional bubble coverage decreases with the magnetic field, which increases the current density and affects the discharge frequency. The analytical model is explored here to investigate the magnetic field influences on departure radius. A novel approach has been adopted to couple the Laplace and Navier stokes equations for studying the magnetohydrodynamic effect. The experimental and analytical results reveal that magnetic flux decreases the bubble departure radius. The regression model explains the impact of controllable factors on surface roughness, material removal rate, and width overcut. The multi-response optimization with the hybridization of response surface methodology and grey relation analysis technique provides the optimum value of material removal rate, width overcut and surface roughness as 1.2 mg/min, 0.046 mm, and 1.58 µm, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Materials & Technologies / Materiali in Tehnologije is the property of Institute of Metals & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The twenty-first century is known as the "century of the ocean." Artificial reefs have been extensively studied and used worldwide as the main infrastructure of marine pastures. At present, research has been primarily focused on developing new environmentally friendly artificial reef construction materials with low emissions, low alkalinity, low cost, and great durability. As a novel low-carbon and environmentally friendly construction material, geopolymer presents considerable potential for building artificial reefs. By changing the alkali-activator dosage, this investigation prepared fly ash geopolymer concrete (FGC) with different strength grades. FGC's mechanics, durability, and marine environmental compatibility were systematically studied as a marine artificial reef construction material. The effect of curing temperature on the performance of FGC was also investigated. Results indicated that the design grade of FGC against sulfate erosion can reach above KS150, and the maximum electric flux of the experimental group is 300.76 C. Moreover, FGC has good compatibility with marine environments. High-temperature maintenance can significantly improve each performance of FGC. Microstructural analysis was performed through a scanning electron microscope secondary electron (SEM-SE), SEM backscattered electrons (SEM-BSE), energy-dispersive X-ray spectroscopy (EDS), and a mercury intrusion porosimeter (MIP). Results showed that the FGC matrix porosity decreases with the increase of alkali-activator dosage, which causes denser pore structures. In addition, the active calcium-containing components in the calcareous aggregate will participate in the geopolymer reaction and generate calcium-rich gel in the interfacial transition zone (ITZ), thus enhancing the mechanical and durability of the material. In conclusion, as a low-carbon construction material, FGC has a broad application prospect in marine artificial reef construction. [ABSTRACT FROM AUTHOR]

This paper focuses on modelling of Heat sink for thermoelectric Generator which requires a heat sink to achieve high electrical output efficiency. Thermoelectricity refers to a phenomenon in which a temperature gradient causes a flux of the electric charge. This work deals with models of different geometries, based on heatsinks designed to improve thermoelectric generator performance. The thermo-electric generator efficiency increased with the temperature gradient ΔT with the cooling junction. Here comparing of the conventional and analytical heat sinks, from analytical heat sinks, we can choose the beat efficient heat sink for thermoelectric generator high performance. The heat sink, whose device is to be improved by the geometry of the Heat sink models designed with different shapes of Fins, provides this cooling junction. After analyzing the various heat sink models, with different geometrical Heat sink fins, cylindrical-shaped fins's-height at 10 mm temperature cooled to 6.7℃ and pressure loss to 1.8Pa from high temperature were found to be most effective for thermoelectric generator efficiency. The improvement in temperature and pressure loss was achieved using the optimized cylindrical heat sink with 10mm fins height design. [ABSTRACT FROM AUTHOR]

In this study, we characterize the electromagnetic parameters of magnetic particles in pseudo hyperbolic (ph) 3-space and analyze the electric and magnetic fluxes associated with these parameters. In particular, we examine power flows as an electromagnetic parameter. This involves determining how energy flows within the system and understanding the energy density and magnitude of the magnetic particles under consideration. In our study, we use curves representing the trajectories of electromagnetic waves and the equations of electric and magnetic fields as materials. First of all, we derive magnetic fields and Lorentz forces for these particles, which you refer to as pseudo-hyperbolic (ph) magnetic particles. Then we calculate electric fields and power flows using the equations relating to Newtonian and Lorentz forces. This step helps us measure the electromagnetic behavior of particles. Finally, we characterize the electric and magnetic fluxes of these power flows. Also, in this section, we provide simulation plots with observations of the results obtained. [ABSTRACT FROM AUTHOR]

In order to study the influence of freeze–thaw cycles on chloride ion corrosion resistance of RPC with copper slag (CS) instead of quartz sand (QS), the 28d uniaxial compressive strength (UCS) of CSRPC with a different CS substitution rate was investigated by unconfined compression tests. The electric flux test method was used to study the chloride ion diffusion resistance of CSRPC after freeze–thaw cycles, and the pore size distribution was obtained through the nuclear magnetic resonance (NMR) method. Then, a mathematical relationship between the chloride ion diffusion coefficient and the pore fractal characteristic parameter T was established to study the effect of freeze–thaw cycles on chloride ion diffusion. Finally, SEM/EDS, XRD, and DTG methods were combined to study the influence of the distribution of Friedel's salts generated after freeze–thaw cycles on chloride ion diffusion in CSRPC. The results indicate that CS has a micro aggregate effect and pozzolanic activity, which can effectively improve the chloride ion diffusion resistance of CSRPC after freeze–thaw cycles. In addition, the electric flux of CSRPC decreases with the increase in freeze–thaw cycles, and the chloride diffusion coefficient is closely related to the pore fractal dimension. [ABSTRACT FROM AUTHOR]

The composite micronized powder is prepared by using blast furnace slag (BFS), water-quenched manganese slag (WQMS), manganese tailing slag (MTS) and desulfurization gypsum (DG) and grinding aid (GA) through orthogonal test optimization design. The effect of the doping amount of each solid waste on the fluidity, activity at different ages and resistance to chloride ion penetration of the composite micropowder was studied systematically, and the exothermic characteristics of hydration of the composite micropowder with the optimal ratio were tested. The results showed that the amount of MTS dosing was the most significant factor among the four factors on the activity index of composite micronized powder at 7 d and 28 d. The activity index at 28 d decreased and then increased with the increase in MTS dosing; the amount of BFS dosing was the most significant factor affecting the fluidity and chloride ion permeation resistance of composite micronized powder. With an increase in BFS dosing, the fluidity ratio of composite micronized powder increased and then decreased; the electric flux of the matrix decreased, and the chloride ion permeation resistance increased. The optimal ratio of composite powder with the highest 28 d activity is 35% BFS, 30% MTS, 0.3% GA, 5% DG and 30% WQMS. The hydration rate and cumulative heat release of the slurry prepared with the optimal ratio of composite micronized powder to cement (1:1) are lower than those of pure cement slurry. The microstructure of the mortar test block prepared with a 1:1 composite of cement is more compact than that of the pure cement mortar test block, and the pores are fewer. [ABSTRACT FROM AUTHOR]

Self-compacting concrete has seen extensive application in both engineering and construction. In order to save building resources, aeolian sand—recycled coarse aggregate self-compacting concrete (ARSCC) is created by partially substituting recycled coarse aggregates (RCA) and aeolian sand (AS) for natural coarse aggregates. For ten groups with different mechanical and durable properties, this study examined the effects of sulfate erosion, chloride penetration resistance, and related impermeability, as well as AS replacement ratios of 20%, 40%, and 60% and RCA replacement ratios of 25%, 50%, and 75% in ARSCC and a control group (A0-R0). According to the study's findings, after sulfate attack, the highest relative dynamic elastic modulus and corrosion resistance factor were obtained with the 20% AS replacement ratio and 50% RCA replacement ratio (A20-R50). The highest impermeability grade and lowest electric flux were obtained with the 20% AS replacement ratio and 25% RCA replacement ratio (A20-R25). X-ray diffraction (XRD) and mercury intrusion porosimetry (MIP) revealed that the addition of aeolian sand and recycled coarse aggregates improved the pore structure of the SCC and increased the densification of the self-compacting concrete, particularly following sulfate attack. This study highlights the importance of recycled aggregates and aeolian sand in engineering applications and the sustainable growth of the concrete industry, both of which support resource conservation and environmental protection. [ABSTRACT FROM AUTHOR]

In this paper, the high flux tubes of 25 mm outer diameter with the content of 8% and 12% nanoparticles were experimentally studied with the refrigerant R141b under atmospheric pressure. The liquid mass flux was controlled from 128.30 to 252.03 kg/m2·s, the maximum heat flux provided by the electric heating rod was 80 kW/m2, and the range of the superheated degree was from −7 to 4 °C. The results indicate that the porous media promotes the phase change at a low superheated degree, and the heat transfer capacity is 1.88 times that of the smooth tube. Additionally, the vapor quality increases significantly with the increase of nanoparticle concentration. Moreover, the heat transfer coefficient decreases as the outer wall temperature increases due to the formation of the gas film but increases with the increase of nano-powder content. Under the same superheated degree condition, the maximum heat transfer coefficient of the sintered porous tube with 12% nano-powder content is 1.3 times that of the tube with 8% nano-powder content. [ABSTRACT FROM AUTHOR]

This paper presents an analytical study of the air-gap magnetic field of a surface permanent magnet (SPM) linear, slot-less machine with a Halbach PM configuration, under the no-load condition. While other analytical formulations of the magnetic field generated by PMs are available, they exhibit some drawbacks, such as only providing a Fourier series, or being suitable to determine magnetic field average values, but not local magnetic field distributions. On the contrary, the proposed approach allows the determination of a unique, closed-form formulation for the slot-less machine air-gap field. This is obtained starting from the complex expression of the magnetic field of a conductor, inside the air gap, between two parallel smooth iron surfaces, obtained by means of the method of images. The magnetic field due to an infinitesimal conductor belonging to a current sheet is then integrated along a segment, providing the expression of the magnetic field due to the corresponding linear current density distribution, for current sheets perpendicular or parallel to the iron surfaces. Any Halbach PM segment disposition can, hence, be obtained via a suitable combination of field distributions generated by couples of current sheets with perpendicular and parallel orientation. Lastly, the no-load magnetic field expression with a Halbach array of PMs is retrieved. The proposed analytical model provides an accurate representation of the magnetic field distribution produced by any Halbach array, with an arbitrary number of segments and orientations. Additionally, the results obtained from the proposed analytical expressions are compared with FEM simulations realized by commercial software, and show an excellent agreement. [ABSTRACT FROM AUTHOR]