Search

To meet the demand for deployable antennas with ultra-compact storage volume and lightweight, an ultra-compact X-band paraboloidal deployable wrap-rib antenna was developed in this paper. The deployable antenna mainly consists of the locking and unlocking device, the deployable reflector, the deployable shell, and the deployable feed source. All the deployable parts of the antenna can be locked in the stowed state using a pre-tightened rope attached to the telescopic sleeve, and the antenna can be deployed with a single click by applying electricity to the endothermic knife. The wrap-ribs were made of stainless steel, which can be easily processed into extremely thin sections and exhibit excellent and stable mechanical properties such as elasticity and strength. The cross-section design of the wrap-rib takes into account the overall layout space, the wrapping capacity and the capacity of the wrap-ribs to tension metal mesh. To achieve optimal surface accuracy for the flexible wrap-rib reflector, the working state shape of the wrap-rib reflector after elastic deformation was obtained through form-finding analysis. The surface accuracy of the reflector was improved by optimizing the shape of the wrap-rib using the genetic algorithm. Finally, two antenna prototypes were assembled. The effectiveness of the mechanism design, as well as the realization and maintenance of surface accuracy, was demonstrated through validation tests such as the deploying test, fundamental frequency test, and surface accuracy measurement. The antenna described in this paper possesses the advantages of lightweight construction, compact storage volume, stable surface accuracy, user-friendly operation, and the reliable deployment strategy. It presents a practical solution for small-aperture ultra-compact deployable antennas, particularly focusing on the design method of wrap-rib and the optimization of surface accuracy. It has certain reference value for large-aperture spatial deployable antennas with a high storage ratio. • A deployable wrap-rib antenna is designed in detail and completely. • Target for microsatellite applications in the design. • The section and shape of the wrap-rib are analyzed and optimized. • Deployment and surface accuracy tests successfully prove the design of such antenna. [ABSTRACT FROM AUTHOR]

Crack-templated thin films, inspired by naturally occurring patterns such as leaf venation, spider webs, and the networked structure of dried egg white, represent a paradigm shift in the design of functional materials. Traditionally, cracks in coatings are seen as defects to be avoided due to their potential to compromise mechanical integrity and performance. However, in this context, cracks are deliberately induced and meticulously controlled to serve as templates for versatile applications. This review explores the latest advances in preparation techniques, including solvent evaporation and thermal stress induction, with a focus on the interplay between material properties (e.g., polymers and ceramics) and process parameters (e.g., drying rates and temperature, layer thickness, substrate interactions) that govern crack behavior. The resulting crack patterns offer tunable features, such as density, width, shape, and orientation, which can be harnessed for applications in semitransparent electrodes, flexible sensors, and wearable and energy storage devices. Our study aims to navigate the advancements in crack engineering in the last 10 years and underscores its importance as a purposeful and versatile strategy for next-generation thin-film technologies, offering a novel and affordable approach to transforming perceived defects into assets for cutting-edge thin-film technologies. [ABSTRACT FROM AUTHOR]

Recently, the transparent electromagnetic interference (EMI) shielding film, which is optical transparent, conductive, and EMI shielding, is widely employed in fields of display, solar cell, EMI shielding, and so on. Here, we utilized Voronoi diagram randomized metallic mesh and 3D printing technology to achieve transparent EMI shielding on curved surface. For the metal grid based on Voronoi diagram, one can realize highly homogeneous light transmission, with that optical performance is superior to that of regular and random quadrilateral mesh. The designed Voronoi diagram meshes were fabricated using aerosol jet (AJ) technology, which needs no mask and can achieve patterns on curved surfaces. The Voronoi metal meshes were fabricated on a 40 × 40 mm2 planar and a plano–convex lens with a diameter of 10 mm and a crown height of 3.7 mm. We investigated the optical transmittance of the Voronoi metal mesh grid and also the imaging performance of plano–convex lens with mesh grid. Furthermore, we analyzed the EMI shielding characteristics of the fabricated Voronoi mesh grids in the Ku-band (12–18 GHz) by using a vector network analyzer, which is higher than 23 dB. Therefore, the proposed Voronoi diagram and AJ technology can provide good diffraction uniformity and an effective method to fabricate the metal mesh grids on conformal surfaces. [ABSTRACT FROM AUTHOR]

A high-gain high-efficiency flexible and transparent film antenna in millimeter-wave is proposed in this paper. Comb structure which can be regarded as developed from the grid array structure is employed to mitigate the loss of the feeding network caused by the lossy metal mesh. The gain of the antenna has low sensitivity to the sheet resistance, which is promising in developing large-scale and high-performance transparent antenna. A large-scale (6. 7 2 λ × 1. 0 5 λ @28 GHz) antenna is designed and fabricated using transparent metal mesh film with sheet resistance of 0.1 Ω /sq and a thin PET film substrate. Bending measurement shows the antenna has excellent mechanical flexibility. A peak gain of 15.92 dBi, radiation efficiency of 65.1%, optical transparency of 84% and 1,000-times bending are obtained. To the best of our knowledge, it is the highest gain and radiation efficiency flexible-transparent antenna reported thus far, which provides a glass-integrated antenna solution for vehicular communication. [ABSTRACT FROM AUTHOR]

A dual-band circularly-polarized transparent antenna for Global Navigation Satellite System (GNSS) is proposed. The antenna is designed with resonance frequencies centered at 1176 MHz and 1582 MHz, targeting the simultaneous coverage of the L5 and L1 bands. Aiming at integration into the glass sun-roof of a vehicle, the antenna is designed using an unperturbed single-substrate layer, i.e., without any via or probe feed. A fine metal mesh based on printed copper is used to achieve around 90% transparency while maintaining satisfactory antenna gain and radiation efficiency within both operation bands. The phenomenon of frequency shifting observed when converting a solid metal-layer antenna to a metal-mesh antenna is thoroughly analyzed and investigated, to assist in speeding up the antenna optimization. The proposed design is fabricated and measured to validate the design concepts.

Highlights A simple strategy of hot imprinting was proposed to construct a densified filler network for the preparation of electrospun polyvinylidene fluoride (PVDF) composite film with high thermal conductivity and electromagnetic shielding performance. First, continuous imprints were obtained by hot pressing on the surface of PVDF fiber film using a metal mesh as a stencil. Magnetic Fe3O4‐modified carbon nanotubes (Fe3O4@CNTs) were then loaded onto the surface of the films using an impregnation method. Finally, the Fe3O4@CNTs/PVDF composite film was fabricated by a three‐layer hot pressing process. The mesh size and filler loading cycles have an important effect on the resulting performance of the composite film. Under the optimal conditions of 1 × 2 mesh size and five loading cycles, the thermal conductivity of the composite film with only 5.16 wt% CNTs content, was 1.91 W/mK, which is an improvement of 51.6% compared to that of the non‐imprinted composite film. The electromagnetic shielding effectiveness of the composite film reached 28.6 dB. This strategy provides a feasible approach for the large‐scale production of high‐performance thermal interface materials. Enhancing continuous filler network in PVDF composite film by hot imprinting. Developing carbon nanotube and Fe3O4 hybrid fillers with a heterogeneous structure. Achieving significant improvements in TC and EMI SE of the composite film. Offering large‐scale production methods of high‐performance thermal interface materials. [ABSTRACT FROM AUTHOR]

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry 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.)

Copyright of Wool Textile Journal is the property of National Wool Textile Science & Technology Information Center 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.)

Ag mesh flexible transparent electrodes (FTEs) are emerging as candidates for In2O3 (ITO) due to their excellent optoelectronic properties and bending stability. However, exposure of Ag meshes to the atmospheric environment can easily cause atmospheric corrosion, leading to a rapid decrease in conductivity. Here, the atmospheric corrosion mechanism of Ag mesh was investigated and the method that encapsulating Ag meshes with spin-coated graphene oxide (GO) to isolate the atmosphere and improve their atmospheric corrosion stability was proposed. Furthermore, GO thin films can be reduced through atmospheric plasma treatment to further improve the electrical properties of the composite thin layer without affecting the encapsulation. The GO/Ag mesh composite film treated with plasma exhibits a transmittance of 75% (550 nm) and over 80% transmittance in the wavelength range above 600 nm, with a sheet resistance of 17.1 Ω/sq. Additionally, the PGO/Ag mesh displays excellent atmospheric corrosion stability, indicated by the fact that the resistance is almost unchanged after 150 days. [ABSTRACT FROM AUTHOR]

The roadway project of broken rock mass in the Shilu Iron Deposit was taken as the research object to discuss the stability control of the surrounding rocks using support patterns with broken rock mass. The grade evaluation of rock mass quality was conducted based on the geomechanical classification of rock mass. The roadway support effect in broken rock mass was calculated. Then, the section convergence characteristics of roadway surrounding rocks were analyzed under the current support scheme using displacement monitoring technology. The conclusions were described as follows: (1) The surrounding rock integrity of the No.6 and No.7 transportation roadways in the middle section of the Baoxiu mining area (Level 120) is poor. Based on geological survey data and rock mass classification, the rock mass quality in this region has been rated as Class IV. The joint support pattern of the anchor net and shotcrete was used according to the support guidelines. (2) The parameters for the support structure within Shilu Iron Deposit were designed, according to the requirements, as follows: the use of Portland cement; a shotcrete thickness of 55 mm; resin bolts with a minimum outer diameter of φ 20 mm and a length of 2200 mm; and row and column spacings of 1100 mm each. Meanwhile, a rectangular metal mesh of 80 × 80 mm was used as the anchor mesh. (3) The cross-section displacement reached 20 mm within a week using the support pattern according to displacement monitoring results of the on-site roadway section. Moreover, the convergence deformation rate significantly changed. However, the rate rapidly decreased after the first week, and the cross-section showed no further deformation after one month. The support pattern could control the displacement of surrounding rocks, which was verified by the monitoring results. [ABSTRACT FROM AUTHOR]

This review systematically evaluates the research and applications of metal mesh‐based catalysts for CO oxidation. CO is a hazardous gas that affects human health and the environment. Traditional cordierite‐based catalysts have drawbacks such as complex preparation, high costs, poor stability, and limited catalytic activity, necessitating exploration of alternative solutions. Monolithic metal mesh‐based catalysts, using metal substrates like Ti, Cu, Fe, FeCrAl, stainless steel, Al and Ni, could address these problems effectively. Generally, each metal mesh requires specific pretreatments to roughen surface and facilitate the loading of active species. Plasma electrolytic oxidation is particularly effective for Ti and Al mesh. This results in a monolithic metal mesh‐based catalyst with uniform surface distribution and fully exposed active species. The review also summarizes in‐situ preparation strategies for metal mesh‐based catalysts and their progress in CO oxidation. Finally, the development potential of metal mesh‐based catalysts is discussed, emphasizing the significant challenges and future prospects for industrial applications. [ABSTRACT FROM AUTHOR]

Through resistance welding experiments, the effects of process parameters and heating elements (HE) on the welding strength of carbon fiber reinforced polyamide 6 (CF/PA6) composites were studied. Stainless steel mesh was used as the heating element for welding CF/PA6 composites. The mechanical properties of the weld were tested using a universal testing machine, and the internal structure and fracture of the joint were analyzed by scanning electron microscopy (SEM). The optimal parameters for welding CF/PA6 composites were determined. In addition, the growth of carbon nanotubes (CNTs) on the surface of the metal mesh significantly improved the welding strength, from 14.016 to 16.31 MPa. The experimental results showed that the optimal parameters included 22A current, 0.3 MPa pressure and 35 s welding time, and the optimal specification of the metal mesh heating element was 200 mesh. The burning time of the metal mesh was 10 s, and the optimum pickling time was 30 s. Highlights: The matrix of the composite material is nylon 6.Improved the experimental process for growing carbon nanotubes.Explore the influence of burning time on welding effect through detection. [ABSTRACT FROM AUTHOR]

The rapid growth of the dye industry and the worsening water resource crisis have drawn significant focus to the treatment of dye wastewater. Membrane separation technology is increasingly being utilized in addressing this issue. However, traditional separation membranes face challenges such as susceptibility to contamination and significant decline in subsequent separation permeance. This work utilizes a straightforward brushing technique to effectively apply a coating comprising titanium dioxide (TiO2) nanoparticles and attapulgite (APT) onto a stainless steel mesh (SSM), equipping it with the capability for dye adsorption and separation. Studies show that coatings with different ratios yield varying degrees of coverage on the SSM. A higher concentration of TiO2/attapulgite results in improved coverage on the SSM, creating a denser coating on the mesh surface and the degree of cross-linking of the coating was as high as 92.22%. The coated meshes exhibited superhydrophilicity uniformly and excellent negatively charged properties. Separation experiments of the meshes with different TiO2/attapulgite ratios were conducted by separating simulated dye wastewater with methylene blue (MB) and safranine T (SaT). The results indicate that the prepared meshes achieved a maximum rejection of over 98.0% for MB and over 96.5% for SaT. In addition, the prepared meshes maintained high dye rejection efficiencies (>96%) even after 10 consecutive separation cycles. The above results indicate that the prepared meshes are promising for application in industrial dye wastewater treatment. [ABSTRACT FROM AUTHOR]

In the field of composite materials, many reports have shown that catastrophic structural damage is caused by lightning strikes. In this study, new design concepts were proposed for the lightning-strike protection of nickel-coated glass/epoxy foam-core composites. Instead of using a neat metal mesh, glass fibers were modified with nickel particles via a plating technique to improve their thermal and electrical conductivities. In addition, a thin Invar plate was inserted at the middle of the structure and a foam core was introduced to reduce damage to the structure. Three models with different materials and stacking sequences were used in this study. Severe damage was experimentally observed following artificial lightning at a peak current of approximately 150 kA when considering a waveform A. Furthermore, numerical prediction was performed to identify the damage mechanisms of the structures. Besides the heat flux source, a mechanical source known as the shock wave overpressure was investigated separately as a new factor for dielectric materials. These two sources of lightning were determined as minor reasons for the structural damage. The failure modes were analyzed for further discussion about the failure mechanism in this study. [ABSTRACT FROM AUTHOR]

At elevated operating temperatures, a large temperature gradient can cause irreparable damage to the solid oxide fuel cells (SOFCs) stack, eventually interrupting the durability of the stack. Metal substrate support could be used to overcome this challenge. However, the application of metal substrate support poses various challenges such as different thermal expansion coefficients, pore diameters, and complex fabrication techniques. Therefore, a first-ever novel and mechanically strong ferritic stainless-steel metal mesh-supported SOFC design is developed to mitigate these challenges. The metal mesh of 200 μm thickness is laminated with tape-casted green films of anode-support, anode functional layer (AFL), and electrolyte films of SOFC. The iso-static pressure of 300 MPa exhibits a firm attachment of the green films of SOFC with the metal mesh. Subsequently, the metal mesh-supported planar SOFC exhibits 3.3 times higher flexural strength compared to the conventional commercial anode-supported planar SOFC. The nano-CuO is added to constituent layers as a sintering aid to attain the maximum density at a lower sintering temperature of 1100 °C. The result shows that the practical application of the metal mesh-supported cell technology has a great potential to overwhelm the mechanical durability of SOFCs. [ABSTRACT FROM AUTHOR]

The relation between the structure of the silver network electrodes and the properties of Cu(In,Ga)Se2 (CIGS) solar cells is systemically investigated. The Ag network electrode is deposited onto an Al:ZnO (AZO) thin film, employing a self‐forming cracked template. Precise control over the cracked template's structure is achieved through careful adjustment of temperature and humidity. The Ag network electrodes with different coverage areas and network densities are systemically applied to the CIGS solar cells. It is revealed that predominant fill factor (FF) is influenced by the figure of merit of transparent conducting electrodes, rather than sheet resistance, particularly when the coverage area falls within the range of 1.3–5%. Furthermore, a higher network density corresponds to an enhanced FF when the coverage areas of the Ag networks are similar. When utilizing a thinner AZO film, CIGS solar cells with a surface area of 1.0609 cm2 exhibit a notable performance improvement, with efficiency increasing from 10.48% to 11.63%. This enhancement is primarily attributed to the increase in FF from 45% to 65%. These findings underscore the considerable potential for reducing the thickness of the transparent conductive oxide (TCO) in CIGS modules with implications for practical applications in photovoltaic technology. [ABSTRACT FROM AUTHOR]

Metallic mesh with complex woven structures is commonly used as the surface in large aperture spaceborne reflector antennas. To study the electrical properties of mesh surfaces characterized by intricate patterns, this paper presents a method for building models to analyze complex meshes. High Frequency Structure Simulator and Computer Simulation Technology (CST) simulation of the reflection coefficients, with Astrakhan's formulation as a reference, confirm that applying the wire-grid model in CST using the tetrahedral mesh type provides sufficiently accurate results. Furthermore, the rectangular periodic wire-grid model is simulated in CST, and its results are compared with those of Astrakhan's formulation. Correlations between reflection characteristics and influence factors, including mesh opening size, wire diameter, nature of wire contact, and wave incident angle, are investigated. To exemplify the applicability of the wire-grid model to complex mesh with irregular pattern shapes, the reflection coefficients of a warp-knitted gold-coated molybdenum mesh woven by multi-wires are measured and compared to the simulated results from the wire-grid model. The results prove that the method proposed in this paper is suitable for modeling metal mesh with complex weave patterns. [ABSTRACT FROM AUTHOR]

Sandwich panels with trapezoidal metal/glass fiber cores are increasingly popular due to their lightweight and energy-absorption properties. This study employs response surface methodology (RSM) and Box-Behnken design to investigate the effects of core angle, fiber orientation, and MCM-48 nanoparticles on the panels' energy absorption and peak force, developing regression models with high R2 values of 0.9027 and 0.9228, respectively. Experimental tests were conducted to validate these models, showing minimal deviation from predicted values. Results indicate that increasing the fiber orientation angle from 30° to 90° enhances energy absorption and peak force by 72.18 and 46.9%, respectively, and adding MCM-48 nanoparticles up to 0.25% weight improves energy absorption by 60.8%. A core angle of 52° balances energy absorption and peak force, while integrating a metal wire mesh within the panels significantly enhances energy absorption and reduces core brittleness. The optimal parameters for maximum energy absorption and minimum peak force include a core angle of 58°, fiber orientation of 73.5°, and no nanoparticles. These findings provide valuable insights into the design and optimization of sandwich panels for various applications. [ABSTRACT FROM AUTHOR]

Beam-column (B-C) joints are recognized as critical regions in reinforced concrete (RC) moment-resisting frames when subjected to seismic loads. Furthermore, these joints may be subjected to high temperatures during their lifespan, which might cause severe structural damage. Accordingly, the seismic response of RC beam-column joints that were subjected to heat (i.e., 400 °C and 600 °C) was investigated in the present experimental work. The joint specimens were divided into three categories: Three joints were kept as is (i.e., reference joints; no strengthening is applied), whereas six joints were strengthened with one and two layers of stainless-steel expanded metal sheet mesh (SSEMSM) in order to improve their performance. To investigate the seismic performance of the joints, a quasi-static cyclic load was applied to the joints to simulate a seismic load. Results showed that the average maximum load for joints strengthened with one and two layers of SSEMSM, respectively, was increased by 11% and 21% at ambient temperature and by 2% and 9% at 400 °C, in comparison with the reference joint. In addition, using one and two layers of SSEMSM, respectively, led to achieving an average of 91% and 100% of the full capacity of the reference joint for B-C joints subjected to 600 °C. Furthermore, the experimental findings show a considerable improvement in the cyclic response of non-ductile RC joints that were strengthened with the SSEMSM strategy and subjected to high temperatures (i.e., higher load capacity, greater displacement, higher dissipated energy, higher ductility, and slower degradation in the secant stiffness). [ABSTRACT FROM AUTHOR]

The National Ignition Facility produced the first nuclear fusion experiment demonstrating net positive energy gain on December 5, 2022. The x-ray streak camera that measures the bang time and burn-width from this landmark experiment had an electronic failure and did not record data. The CCD sensor was replaced with a radiation hardened CMOS sensor that has since demonstrated successful operation on repeat ignition shots. Concurrently, an instrument artifact was identified that occurs when the signal consists primarily of energetic x rays >15 keV (common on burning plasma experiments). This artifact, which appears as a background pedestal, arises from the x-ray back-fluorescence generated by the solid metal accelerating mesh behind the photocathode in the streak tube. We have mitigated this background signal by limiting the sensitive area of the photocathode. Herein, the details of the modifications and the results are presented. [ABSTRACT FROM AUTHOR]

In this study, we propose a method to measure the shielding effectiveness of relatively small mesh specimens, which are smaller than those typically used in free-space measurements, in S-band free space, where diffraction effects are significant, without using a lens horn antenna. The proposed method involves placing an absorber panel between the transmitting and receiving antennas and applying a time-gating technique to the measured scattering parameters to determine the shielding effectiveness. First, the shielding effectiveness was calculated by modeling the metal mesh specimen at the wire grid level, which was verified using FEKO simulation. We then conducted shielding effectiveness measurements of metal mesh specimens A and B in an actual S-band free space. Subsequently, the measured results are compared and validated against the results derived from the formulas and simulations. The differences among the measured, formula-derived, and simulation results were all within 3 dB, confirming the validity of the proposed measurement method. [ABSTRACT FROM AUTHOR]

Firmly, the bearing capacity test of 1:1 equal ratio pillar under different constraint forms and different filling medium conditions was carried out. The results show that the binding pillar-forming effect is relatively good. The constraint ability of unconstrained, metal mesh, polyester mesh, hooked iron flat-hoop bushing, bellows, and spiral iron pipe is enhanced, in turn, and the carrying capacity is improved successfully. The homogeneity of high-water materials is better than concrete, and they have better compressibility, but their carrying capacity is relatively weak. The carrying capacity of concrete pillars is generously higher than that of high-water materials, but the compressibility is poor. Second, the migration characteristics of the surrounding rock structure of the gob-side entry retaining and the rule of side support are analyzed, the requirements of the side support are pointed out, and the side-support technology of the binding pillar is proposed. Taking Hijiata Mine's 50108 working face gob-side entry retaining as an example, the bellows pump-filled concrete pillar is used as the side support body, supplemented by handling steel mesh and air-duct cloth, and toughness material is sprayed between the pillars to seal the goaf, meeting the requirements of side support and road stability. The pillar has the characteristics of high early strength, strong final consolidation carrying capacity, good crimping effect, high mechanism degree, fast construction speed, less concrete consumption, low comprehensive cost, etc., and it has a good application prospect in the gob-side entry retaining or rapid advanced working face. [ABSTRACT FROM AUTHOR]

Gas foil bearings, which are oil-free and exhibit low energy losses, are used in high-speed rotating machinery. Because gas is used as the working fluid, there is a need to improve damping performance using support structures. Additionally, the support structure, which becomes increasingly complex shaft performance, needs to be simplified. This study proposes a new bump mesh foil bearing focusing on the support structure and experimentally verifies its static and dynamic characteristics. The bump metal mesh foil bearing is a simple structure that combines a bump shape and metal mesh. Static load and hammering tests were conducted to evaluate the static characteristics, and the frictional torque and vibration at high-speed rotation were measured to evaluate the dynamic characteristics. The bump metal mesh foil bearing exhibited excellent damping performance owing to the friction damping caused by the bump shape and metal mesh; however, the rigidity of the bump metal mesh foil bearing was reduced. The bump metal mesh foil bearing exhibited the same level of lifting performance as the bump foil bearing, and vibration reduction at high-speed rotation was confirmed. Thus, the combination of the bump foil and metal mesh bearings yielded good results in terms of vibration characteristics.

Aiming at solving the problem of support failure caused by a large deformation of roadway surrounding rock in a deep soft coal seam, and taking the surrounding rock control of the roadway in the 11-2 coal seam in Zhujidong Coal Mine as the research background, numerical simulation and field industrial test and inspection methods were used to study the support effect of a supporting system of gob-side entry in deep soft coal seam. The deformation characteristics of various supporting systems of metal mesh, diamond mesh, metal mesh with anchor rod, steel ladder beam, M-shaped steel belt, 14#b channel steel, and 11# I-steel in the goaf supporting body of deep soft coal seam were studied under vertical load. The supporting effect of effective compressive stress zone generated by bolt and cable under different row spacings and lengths was analyzed, and the law of variation in the compressive stress field generated by supporting members with supporting parameters was explored. The length and interrow distance of bolt and cable were compared, respectively, and reasonable supporting parameters were selected. Based on the abovementioned research results and the geological conditions of the 1331 (1) track roadway, the support scheme of the 1331 (1) track roadway was designed, and the industrial test was carried out. The results show that the surrounding rock of the roadway is within the effective anchorage range of the supporting body, the active support function of the supporting components has been fully brought into play, and the overall control effect of the surrounding rock of the roadway is good, which can ensure the safety and stability of the goaf roadway. The maximum displacement of the roof and floor of the roadway is 86 mm, the maximum displacement of the solid coal side is 50 mm, the maximum displacement of the coal pillar side is 70 mm, and the maximum separation of layers is 22 mm. There is no failure phenomenon in relation to the anchor bolt and cable, and the overall deformation of the roadway surrounding the rock is good, which can provide some references for roadway-surrounding-rock control under similar conditions in deep coal seams. [ABSTRACT FROM AUTHOR]

In this paper, we propose a graphene-based radar cross section (RCS) tunable antenna that utilizes metal mesh and graphene, both of which are optically transparent. The graphene sandwich structure is introduced to replace traditional components like diodes, micro-electro-mechanical systems (MEMS), and varactors, acting as an electromagnetic wave controller and significantly simplifying the device's complexity. By applying different voltages, the electrical properties of graphene are altered, enabling the regulation of reflection, transmission, and absorption of electromagnetic waves. This not only modifies the antenna's pattern but also achieves a substantial reduction in out-of-band RCS. The radiation and scattering mechanism of the antenna is carefully elaborated. The numerical and experimental results match well, which validates the effectiveness of the proposed method. The optical transmittance of the device is 27.9% at 550 nm, and the out-of-band RCS reduction is 10.01 dB at 3.83 GHz. The transparent, RCS tunable antenna proposed has significant potential applications in optical and microwave stealth technology. [ABSTRACT FROM AUTHOR]

Evaluating human–wildlife conflict is necessary to reach positive long-term management solutions and aid the conservation of biodiversity. We used indirect approaches to evaluate the Human–Neotropical otter conflict in three river basins with high fishing activity in western Mexico and provided recommendations to mitigate the conflict by identifying the variables that increase the risk of predation of ponds by otters. Human–Otter conflict was moderate, and the opinions of community members toward otters were mostly negative, particularly those of the fishing sector. However, after offering environmental education workshops, the number of people recognizing the importance of protecting the species increased, which could result in the acceptance and tolerance toward otters. Avoiding building ponds at ground level and covering ponds with metal mesh, especially in fish-farms located in the middle and upper areas of rivers, as explored with fish-farmers, merits more experimentation, since it could be a good means for reducing the conflict. [ABSTRACT FROM AUTHOR]

Current transcathether heart valves rely on metal mesh stents, resulting in discontinuous stent‐leaflet interfaces that introduce stress concentrations, reducing valve lifetime. This work aims to investigate non‐conventional methods to create a fully polymeric transcatheter heart valve, exhibiting a quasi‐continuous interface with hemocompatible leaflets with high durability potential. Polyetheretherketone (PEEK) is of particular interest as a cardiovascular material due to hemocompatibility and mechanical resilience, highly relevant for catheter delivered valves. For increased reproducibility and design freedom, an autoclave process was used to manufacture thin‐ply PEEK composite stents. We demonstrated that a suitable membrane material during manufacturing is essential to evenly distribute pressure around the stent. Meanwhile, a modified vacuum forming process was used to simultaneously form and attach PEEK leaflets to the stent using a heated mold. This simple and robust method enables rapid manufacturing of an integral PEEK‐based valve design, resulting in improved stent‐leaflet bonding, demonstrating an alternative to conventional dip‐coating. The customized vacuum forming causes a controlled annealing effect in semicrystalline materials such as PEEK. Processing PEEK leaflets at higher mold temperatures results in higher crystallinity, elastic modulus, and bond strength. These processes enable greater design flexibility and promote composite materials for use in heart valve devices. Highlights: Developed manufacturing processes for PEEK‐based heart valve implants.Proof of concept for thermoforming of semi‐crystalline PEEK leaflets.Demonstrated effect of processing temperature on valve mechanical properties.Autoclave processing and vacuum forming enable new heart valve designs. [ABSTRACT FROM AUTHOR]

A tri-band shared-aperture antenna for Sub-6 GHz/millimeter-wave (mmWave) applications with a scanning beam is proposed. Using structural multiplexing, the dual-band Sub-6 GHz mesh patch antenna and the millimeter-wave (mmWave) Fabry-Perot cavity antenna (FPCA) share the same radiating aperture. The metal mesh patch acts as both the radiator of the dual-band mesh patch antenna and the partial reflective surface (PRS) of the FPCA. The mechanism of the FPCA is analyzed using the ray tracing method. With the designed single-layer PRS, the proposed antenna features a scanning beam in the mmWave band without the need for tuning elements and feeding networks. An aperture-coupled patch antenna is designed as the feed source for the FPCA. Additionally, by optimally shaping the metal mesh, the patch antenna generates dual-band resonances. The antenna prototype is fabricated and measured. Measured results show that the impedance bandwidth of the antenna is 2.07% (2.39 − 2.44 GHz), 24.79% (3.18 − 4.08 GHz), and 28.42% (24.90 − 33.15 GHz), respectively. The tri-band peak gains are 8.18 dBi, 8.39 dBi, and 17.41 dBi, respectively. The beam scans from 2° to 39° in the frequency range of 25 − 33 GHz. [ABSTRACT FROM AUTHOR]

In this paper, the shear behavior of ferro-cement hollow beams is investigated experimentally and analytically. Ten reinforced concrete beams with cross-sectional dimensions of 100 × 200 × 1300 mm and a clear span of 1000 mm were cast and tested until failure under a two-point loading system. Ferrocement beams in this research contained either an autoclaved aerated lightweight brick core (AAC) or an extruded foam core (EFC) and were reinforced with either expanded metal mesh (EMM) or welded wire mesh (WWM). The structural behavior of the studied beams, including first crack, deflection, ultimate load, crack pattern, failure mode, and ductility index, was investigated. The experimental data were used to validate finite element models created with the ABAQUS finite element program. It can be concluded that the optimum performance of ferrocement beams can be achieved using beams with a second layer of expanded steel mesh as additional reinforcement, which led to an increase in the ultimate load and maximum deflection by 12.9% and 22.8%, respectively. Furthermore, the Numerical results agreed with the experimental results, where the ratio between the NLFE ultimate loads and the experimental ultimate loads varies between 1.02 and 1.07, with an average ratio of 1.04. [ABSTRACT FROM AUTHOR]

This study aims to assess the hybridization effect on the perforation threshold of Low-Velocity Impact (LVI) in thermoplastic glass composite laminates, incorporating layers of resin-impregnated stainless-steel mesh. Reinforcing methodologies such as hybridization are recently being adopted as a practical approach to increasing the energy-absorbing capacity of polymer composites. In the current paper, a multi-step hot press lamination method has been employed to fabricate the hybrid composite laminates strengthened with stainless-steel mesh layers. Several stacking sequences, metal mesh wire sizes, orientation and position relative to the impactor have been examined under various LVI energies. It was revealed that the LVI penetration energy was increased for the thermoplastic-based composite laminates reinforced with stainless-steel mesh layers. Furthermore, the LVI penetration energy threshold was significantly influenced by the metal mesh wire size, orientation and stacking sequence. Finally, the backlight method capability was assessed to detect the after-impact interlaminar damages. [ABSTRACT FROM AUTHOR]

The installation of sand screens in open-hole completions in the wellbore is crucial for managing sand production. The main reason for using standalone screens in open-hole completions is their relatively reduced operational complexity compared to other sand control technologies. However, directly applying the screen to the bottom of the hole can lead to an incorrect screen type selection, resulting in an unreliable sand control method. To address this issue, a sand retention test is conducted to evaluate the performance of a standalone screen before field installation. Nevertheless, current sand retention test setups encounter several challenges. These include difficulties in identifying minimum retention requirements, interpreting results in the context of field conditions, and replicating field-specific parameters. The existing sand retention test introduces uncertainties, such as inaccurately replicating field requirements, inconsistent selection of wetting fluids, flow rates, and channel formation, leading to variations in the choice of the optimal screen using this test. In response to these challenges, this study aims to review the sand retention test and propose an improved sand retention method to overcome these problems. The focus of this article is to provide an in-depth analysis of previous sand retention test setups, their contributions to characterizing sand screens, and the parameters utilized in determining test outcomes. Additionally, this review outlines a procedure to investigate the impact of different particle sizes on screen erosion. Key findings emphasize the importance of using high-quality materials, proper screen design to resist damage and erosion, achieving acceptable natural packing behind the screen, and considering factors such as geology, wellbore conditions, and installation techniques. The analysis reveals that a high quantity of finer and poorly sorted sand increases sand production. The study recommends performing a sand pack test closer to reservoir conditions for better evaluation. Premium sand screens demonstrate the highest retention capacity, followed by metal mesh and wire-wrapped screens. Additionally, geotextiles show potential for enhancing sand retention, and screen design affects erosion resistance and service life. [ABSTRACT FROM AUTHOR]

In response to the poor active support effect of the surface protection components in soft coal roadway and the continuous expansion of the broken range of local exposed surrounding rock, which leads to the failure of anchor rod and cables, a mesh grouting surface type prestressed application technology has been developed. The authors conducted post mesh grouting tests on different specifications and models of metal mesh, and obtained the mechanical response characteristics of the support system during the application of active surface prestressing. Based on this, the post mesh grouting tests on the roof and two sides of the mesh under on-site conditions were carried out, verifying the applicability of post mesh grouting technology. The research results indicate that: ① There is a gap between the metal mesh and the coal wall, which leads to poor active support ability. The continuous expansion of the broken range of the exposed surrounding rock is the main controlling factor for the failure of anchor rod and anchor cable support. Filling the uneven structure around the contact surface between the metal mesh and the coal wall, increasing the active support ability of the protective surface components, and comprehensively sealing the surrounding rock are the technical means to improve the anchor mesh support system; ② Injecting and filling between the metal mesh and the surrounding rock can achieve the application of surface active pre-stress. The trend of surface stress change is mainly divided into: the initial stage of constant surface stress, the stage of increasing surface stress, and the stage of reducing surface stress to stable state; ③ During the process of grouting behind the mesh, the trend of changes in surface stress values is closely related to the grouting pressure and deformation of the metal mesh. During the process of increasing surface stress, the grouting pressure and deformation of the metal mesh also increase accordingly; ④ Grouting behind the mesh can effectively alleviate the stress concentration of the cable tray. During the process of increasing the surface stress value, the pre-tightening force of the cable with stress concentration can show a small decrease trend, while the pre-tightening force of the cable with relatively uniform stress shows a synchronous upward trend during the process of increasing the surface stress value. The technologies developed are expected to become supporting technologies for rock bolt support, providing technical and theoretical references for the treatment of complex and difficult roadway.

A composite material consisting of δ-MnO2 flower-like/kaolin was modified with (3-aminopropyl) triethoxysilane (APTES) and utilized for separating sunflower oil from water using a metal mesh membrane. The δ-MnO2 flower-like/kaolin/APTES/metal mesh membrane was characterized using various techniques such as X-ray diffraction analysis, Fourier-transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy mapping, Brunauer–Emmett–Teller theory/Barrett–Joyner–Halenda, atomic force microscopy, and contact angle. Based on the outcomes of the conducted experiments, it was observed that the maximum porosity was associated with the δ-MnO2 flower-like/kaolin/APTES 15 (wt.%)/metal mesh (MKA(15 wt.%)M) membrane, and the porosity was calculated to be 0.58%. The blocking filtration model was employed, and a complete blocking model was obtained with a value of n = 2.15 for MKA(15 wt.%)M membrane. The response surface methodology based on Box–Behnken design was utilized to investigate the effect of parameters such as weight percentage of APTES (wt.%), mass of δ-MnO2 flower-like/kaolin/APTES (MKA) (g), volume of oil in water (mL), and temperature (°C) on the flux (L/m2·h) and rejection (%). Under optimal conditions, weight percentage of 13.32 (wt.%) of APTES, concentration of 0.2 (g) of MKA, volume of 37.10 (mL) of oil in water, and a temperature of 59.06 (°C) were obtained. These conditions resulted in a flux of 5977 (L/m2·h) and a rejection rate of 99.99% for 9 s. The kinetic studies indicated that the pseudo-second-order model had the highest correlation coefficient of 0.9991, thus displaying the most agreement with the experimental data. [ABSTRACT FROM AUTHOR]

This study was conducted to derive a quality factor for the evaluation of an enclosure with a metallic wire mesh. The electrical characteristics of the metal mesh surface can be determined through equivalent surface impedance conversion; thus, an enclosure was manufactured after analyzing the scattering parameters of the metallic wire mesh surface. The quality factor of the enclosure can be derived simply by measuring a single standard antenna bonded by 1-port. To verify the effectiveness of the 1-port time domain quality factor derivation method, a numerical simulation was performed using the Finite Integration Technique (FIT) of commercially available software CST Microwave Studio. The verified quality-factor derivation method was applied to an enclosure with a metallic wire mesh surface. A quality factor measurement experiment was performed for the case in which one side of the enclosure was in the opening surface, one side of the enclosure was a metallic wire mesh surface, and all the surfaces of the enclosure were closed with metal. Based on the measurements, the quality factor in the case of Open was the lowest at 26.82 dB, followed by 32.24 dB for the case of Mesh and 32.51 dB for the case of Closed. [ABSTRACT FROM AUTHOR]

This paper analyzed the visibility phenomenon caused by the metal mesh of FMLOC under the point source illumination. We built a simulation model based on PSF of Huygens integral mode, processed the simulation results with background filtration algorithm. When there is only one graphic unit and no gap spacing between single‐cycle graphic units in FMLOC sensor pattern, the phenomena were significantly improved. [ABSTRACT FROM AUTHOR]

This study introduces a super‐fast and precise simulation algorithm capable of generating human‐visible moiré patterns, taking into account real structures with diverse patterns. The simulation of entire area of a mobile phone screen can be completed in less than 10 minutes, demonstrating a remarkable efficiency improvement of approximately 1200‐fold compared to traditional ray tracing method. The improvement comes from that we use a simplified method of calculating geometric areas instead of the first‐principles approach used in ray tracing. Based on the proposed algorithm, the moiré patterns ofAoD are optimized and the display quality is guaranteed. [ABSTRACT FROM AUTHOR]

Simulation and experimental studies are carried out on single‐layer and double‐layer embedded metal meshes (SLEMM and DLEMM) to assess their performance as transparent electromagnetic interference (EMI) shielding. The structures consist of silver meshes embedded in polyethylene terephthalate (PET). As a transparent electrode, SLEMMs exhibit a transparency of 82.7% and a sheet resistance of 0.61 Ωsq−1 as well as 91.0% and 1.49 Ωsq−1. This performance corresponds to figures of merit of 3101 and 2620, respectively. The SLEMMs achieve 48.0 dB EMI shielding efficiency (SE) in the frequency range of 8–18 GHz (X‐ and Ku‐bands) with 91% visible transmission and 56.2 dB EMI SE with 82.7% visible transmission. Samples exhibit stable performance after 1000 bending cycles with a radius of curvature of 4 mm and 60 tape test cycles. DLEMMs consist of fabricating SLEMM on opposite sides of the substrate where the distance can be varied using a spacer. Simulations are performed to investigate how varying spacer distance between two layers of metal meshes influences the EMI SE. DLEMMs are fabricated and achieved an EMI SE of 77.7 dB with 81.7% visible transmission. SLEMMs and DLEMMs may have a wide variety of applications in aerospace, medical, and military applications. [ABSTRACT FROM AUTHOR]

The results of a research aimed at analyzing the use of wire mesh in constructions during the first decades of the 20th century are presented. Based on field work and documentary research, applying the historical-logical method, this article documents which were the most used meshes in Cuba, for what purpose and in what functions, and specifically, how they were used in Havana to cover wooden architecture with the purpose of modifying its appearance. The results obtained show that these prefabricated reinforcements were widely used in Havana during the period between the beginning of the First World War and 1930, and constitute an updated vision on the subject since the use of metallic meshes in the constructions of that period has not been practically approached by the specialized bibliography. [ABSTRACT FROM AUTHOR]

In order to effectively improve the seismic and impact resistance performance of soft rock tunnels, a composite support method was proposed and validated in the paper. The UDEC (Universal Distinct Element Code) model of soft rock layers was established, and the movement and subsidence characteristics of the roof and floor of the rock layers under impact loads was simulated and calculated. As a result, a composite support scheme with good cushioning performance was proposed. The top and sides of the tunnel were supported by a combination of anchor rods of different lengths and metal mesh, reinforced by steel beams and vibration absorbing filler around. The anchor rod was designed as a segmented loading structure, and can be set to different preloading forces based on the internal deformation of the rock layer. The dynamic response testing scheme was designed, and the results indicate that the segmented loading anchor rod has a significant buffering effect on the response to impact load, and can provide reasonable tension feedback at different stages. Research has found that when the water cement ratio is 0.5-1.5, the curing efficiency and strength are both higher. In order to compare the seismic performance of composite support and traditional constant resistance anchor rod support, local blasting experiments were conducted. Based on a blasting vibration tester, a data detection and transmission system were designed to obtain the vibration speed of the tunnel roof during the vibration process. The research results show that composite support can reduce the maximum vibration by more than 40 %, stabilize the fragmentation coefficient at 1.38, and have a very significant vibration reduction effect. [ABSTRACT FROM AUTHOR]

In stealth applications, there is a growing emphasis on the development of radar-absorbing structures that are efficient, flexible, and optically transparent. This study proposes a screen-printed metamaterial absorber (MMA) on polyethylene terephthalate (PET) substrates using indium tin oxide (ITO) as the grounding layer, which achieves both optical transparency and flexibility. These materials and methods enhance the overall flexibility and transparency of MMA. To address the limited transparency caused by the silver nanoparticle ink for the top pattern, a metal mesh was incorporated to reduce the area ratio of the printed patterns, thereby enhancing transparency. By incrementing the fractal order of the structure, we optimized the operating frequency to target the X-band, which is most commonly used in radar detection. The proposed MMA demonstrates remarkable performance, with a measured absorption of 91.99% at 8.85 GHz and an average optical transmittance of 46.70% across the visible light spectrum (450 to 700 nm), indicating its potential for applications in transparent windows or drone stealth. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials 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.)

With the growing demand for high‐quality Organic Light Emitting Diode (OLED) display, the design of screen structure by panel manufacturers needs to consider optical performance optimization carefully, such as Wide Angle Difference (WAD). The users hope that visual color bias of the OLED display on different angles appears as small as possible, and no red visual test will be particularly accepted. The OLED display panel is usually composed of Array substrates, OLED devices, Thin Film Encapsulation (TFE) layers, touch units, Polarizers and top cover plates. The touch units contain a metal mesh, which is distributed throughout the display screen and has a great impact on the optical performance of large viewing angles. This paper aims to clarify the optical design requirements of metal mesh and provide reference for OLED optical display designers. [ABSTRACT FROM AUTHOR]