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The promising routes of metallic additive manufacturing favor the fabrication of refined functional components. Nonetheless, dealing with the Laser Powder Bed Fusion (L-PBF) parameters and costs for making the most of this technology is still an issue. The challenge gets bigger when considering less explored parameters, such as the process atmosphere and build location. So, this study aimed to address the main differences in microstructure, crystallography, mechanical properties, and surface finishing of maraging steel components manufactured under two different atmospheres (N2 and a mixture of 75%Ar-25%He atmospheres) and three build locations arranged along the gas flow direction. Based on experimental characterizations, the porosity fraction, microstructural constituents and metallurgical flaws, phase composition and martensite matrix crystallographic parameters, macrotexture, mechanical properties, roughness, and surface residual stress were investigated and compared for the different manufacturing conditions. The porosity fraction had the most expressive changes with the gas type and the build location, reaching a 53% overall reduction under N2 and a 112 to 302% rise for the front located sample compared to the others. The underlying mechanisms involved in the observed results, mainly related to process by-products behavior, were discussed. Broadly, the N2 atmosphere stands out over the analyzed properties. These findings underscore the role of atmospheric selection in the LPBF process, considering the overall quality and performance of the fabricated material and the possibility of cost reduction. [ABSTRACT FROM AUTHOR]

Freshwater purification from wasted water and seawater is crucial in addressing the global problem of water scarcity. Porous fiber felt with a micro/nanostructure emerges as an efficient approach for water purification; however, its production usually relies on chemical postprocessing to create micro/nano structures on the fiber surface, which might pollute the environment. This study proposed an ecofriendly method to produce micro/nanostructured copper fiber felt without chemical treatment. First, a new transverse-feeding vibration cutting is proposed to fabricate micro/nanostructured fibers with controllable structure characteristics. Through the sintering of the structured fibers without postprocessing, the fiber felt can be produced in an ecofriendly way and exhibit special wettability and excellent photothermal properties. Felt-based freshwater purification, including oil–water separation and solar-driven seawater desalination, can be realized effectively. Results show an oil–water separation efficiency of > 90% and a high evaporation rate of water of > 1.08 kg m−2 h−1 at 73 mW cm−2 are achieved, demonstrating the application prospect of the produced fiber felt. Highlights: A transverse-feeding vibration cutting process is proposed to fabricate micro/nanostructured copper fibers. Micro/nanostructured based felts can achieve special wettability and corresponding wettability transition. Micro/nanostructured fibers can enhance the felts' photothermal conversion ability and reduce heat transfer loss. [ABSTRACT FROM AUTHOR]

The discovery of single-atom catalysts (SACs) represents a groundbreaking advancement in the field of catalysis over the past decades. With the in-depth exploration of relevant structure-activity relationships, the metal-support interaction (MSI) is widely adopted to elucidate variations in electronic structure and coordination configuration of atomic active sites on various kinds of supports. Herein, we briefly summarize the metal oxide supports for SACs fabrication, including the distinctive characteristics of metal oxide supports, enlightening advancements in metal oxide support-based SACs (MO-SACs), feasible preparation methods for MO-SACs and effective regulation strategies of MSI effect in MO-SACs. In addition, we present our viewpoints and outlook in this field to stimulate rational design and construction of novel MO-SACs applied in diverse renewable energy devices, while some universal suggestions are sincerely given to provoke thoughtful considerations during the research process. [ABSTRACT FROM AUTHOR]

The presence of missing components in incomplete instances precludes a kernel-based model from incorporating partially observed components of incomplete instances and computing kernels, including Gaussian kernels that are extensively used in machine learning modeling and applications. Existing methods with Gaussian kernels to handle incomplete data, however, are based on independence among variables. In this study, we propose a new method, the expected Gaussian kernel with correlated variables, that estimates the Gaussian kernel with incomplete data, by considering the correlation among variables. In the proposed method, the squared distance between two instance vectors is modeled with the sum of the correlated squared unit-dimensional distances between the instances, and the Gaussian kernel with missing values is obtained by estimating the expected Gaussian kernel function under the probability distribution for the squared distance between the vectors. The proposed method is evaluated on synthetic data and real-life data from benchmarks and a case from a multi-pattern photolithographic process for wafer fabrication in semiconductor manufacturing. The experimental results show the improvement by the proposed method in the estimation of Gaussian kernels with incomplete data of correlated variables. [ABSTRACT FROM AUTHOR]

Injection moulding has been a pivotal technology in the mass production of polymer optics for many years. The surface quality of the moulding inserts exerts a significant influence on the quality of the optics produced. In the production of micro-structured polymer optics, such as Fresnel lenses, conventional isothermal injection moulding is unable to achieve the requisite surface accuracy. Variothermal injection moulding allows for improved surface accuracy and reduced residual stresses, but increases technical effort and cycle times. To reduce the cycle time and residual stresses of variothermal injection moulding, the potential of additive manufacturing of Al-40Si for the fabrication of moulding inserts is investigated. In order to achieve these objectives, the offered design freedom of additive manufacturing is investigated with a view to developing optimised conformal cooling channels. Numerical methods will be used for thermal and structural analyses. The performance of the newly developed moulding insert is evaluated experimentally by thermographic measurements and the measurement of stress birefringence on replicated PMMA samples. [ABSTRACT FROM AUTHOR]

Advances in additive manufacturing enable fabrication of architected materials composed of microstructures with extreme mechanical properties. In the design of such architected materials, the parameterization of microstructures determines not just the computational cost but also connectivity between adjacent microstructures. In this paper, we propose a periodic composite function (PCF)-based approach for designing microstructures. The shape of the microstructures is characterized by the value of the periodic composite functions. The proposed method can program microstructures with both positive and negative Poisson's ratios by a small number of parameters. Furthermore, due to its implicit representation, the proposed method allows for continuously tiling of microstructures with different mechanical properties. Explicit geometric features of the PCF-based microstructures are extracted, and the condition to maintain connectivity between adjacent microstructures is derived. Based on the proposed approach, multiple groups of 2D and 3D microstructures with Poisson's ratios ranging from negative to positive are presented. Combining with a deep neural network (DNN)-based surrogate model to predict macroscopic material properties of the microstructures, the proposed method is applied to the design of architected materials for elastic deformation control. Numerical examples on both microstructure representation and architected materials design are presented to demonstrate the efficacy of the proposed approach. [ABSTRACT FROM AUTHOR]

Biosensors are a new type of sensor that utilize biologically sensitive materials and microbially active analytes to measure a variety of biological signals. The purpose of monitoring is achieved by combining these sensitive materials with analytes such as proteins, cells, viruses, and bacteria, inducing changes in their physical or chemical properties. The use of nanomaterials in fabricating surface acoustic wave (SAW) biosensors is particularly noteworthy for the label-free detection of organisms due to their compact size, portability, and high sensitivity. Recent advancements in the manufacturing techniques of SAW biosensors have significantly enhanced sensor performance and reliability. These techniques not only ensure precise control over sensor dimensions and material properties but also facilitate scalable and cost-effective production processes. As a result, SAW biosensors are poised to become powerful tools for various clinical and rapid detection applications. [ABSTRACT FROM AUTHOR]

AbstractThe treatment of recurrent genital herpes typically involves daily doses of acyclovir for extended periods. Additive manufacturing is an intriguing technique for creating personalised drug delivery systems, which can enhance the effectiveness of treatments for various diseases. The vaginal route offers a viable alternative for the systemic administration of drugs with low oral bioavailability. In this study, we produced different grades of thermoplastic polyurethane (TPU) filaments through hot-melt extrusion, with acyclovir concentrations of 0%, 10%, and 20% by weight. We used fused filament fabrication to manufacture matrix-based devices, including intrauterine devices and intravaginal rings. Our results, obtained through SEM, FTIR, and DSC analyses, confirm the successful incorporation of acyclovir into the matrix. Thermal analysis reveals that the manufacturing process alters the organization of the TPU chains, resulting in a slight reduction in crystallinity. In our in-vitro tests, we observed an initial burst release on the first day, followed by sustained release at reduced rates for up to 145 days, demonstrating their potential for long-term applications. Additionally, cytotoxicity analysis suggests the excellent biocompatibility of the printed devices, and biological assays show a remarkable 99% reduction in HSV-1 replication. In summary, TPU printed devices offer a promising alternative for long-term genital herpes treatment, with the results obtained potentially contributing to the advancement of pharmaceutical manufacturing. [ABSTRACT FROM AUTHOR]

We present a sensor array of microscale organic electrochemical transistors (OECTs) using poly (3,4−ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) as the channel material. The devices show high sensitivity and selectivity to detect dopamine (DA) with platinum (Pt) as a pseudo−reference gate electrode. First, we describe the wafer−scale fabrication process for manufacturing the PEDOT:PSS OECTs, and then we introduce a dilution method to adjust the thickness of the PEDOT:PSS film. Next, we investigate the effect of the film thickness on the sensitivity of DA detection. Reducing the film thickness enhances the sensitivity of DA detection within the concentration range of 1 μM to 100 μM. The OECTs show impressive sensitivitywith a limit of detection (LoD) as low as 1 nM and a high selectivity against uric acid (UA) and ascorbic acid (AA). Finally, we modify the surface of the Pt gate electrode with chitosan to improve the selectivity of OECTs at high concentrations of up to 100 µM to expand the detection range. [ABSTRACT FROM AUTHOR]

This paper presents a methodological approach to conducting a literature review on additive manufacturing (AM), which is a groundbreaking manufacturing technique that involves the successive layering of materials to create components. The use of AM not only reduces manufacturing waste but also saves time and simplifies assembly processes. The current research focused on exploring the advances of AM in fabricating self-lubricating components. By using specific keywords, relevant data sources were extracted from databases. The literature review highlights the extensive exploration of AM in tribological research, demonstrating its successful application in creating self-lubricating components that have yielded positive results. [ABSTRACT FROM AUTHOR]

We present the design of an on-chip integrated photon pair source based on Spontaneous Four Wave Mixing (SFWM), implemented on a ring resonator in the 4H Silicon Carbide On Insulator (4H-SiCOI) platform, compatible with a solid state quantum memory in the telecommunications band. Through careful engineering of the waveguide dispersion and micro-ring resonator dimensions, we found solutions where the signal photons are emitted at 1536.48 nm with a bandwidth of ∼ 150 MHz, enabling the interaction with the hyperfine structure of Er 3 + ions. Simultaneously, the idler photons are generated at 1563.86 nm, matching the central wavelength of a specific channel in a commercial dense wavelength division multiplexing system. The proposed device fulfill all the spectral requirements in a simple ring-bus coupled waveguide configuration with design parameters within the range of reported values for similar resonators, making feasible its manufacturing with current fabrication capabilities. [ABSTRACT FROM AUTHOR]

Multiphase microfluidic has emerged as a powerful platform to produce novel materials with tailor-designed functionalities, as microfluidic fabrication provides precise controls over the size, component, and structure of resultant materials. Recently, functional materials with welldefined micro-/nanostructures fabricated by microfluidics find important applications as environmental and energy materials. This review first illustrated in detail how different structures or shapes of droplet and jet templates are formed by typical configurations of microfluidic channel networks and multiphase flow systems. Subsequently, recent progresses on several representative energy and environmental applications, such as water purification, water collecting and energy storage, were overviewed. Finally, it is envisioned that integrating microfluidics and other novel materials will play increasing important role in contributing environmental remediation and energy storage in near future. [ABSTRACT FROM AUTHOR]

Industrial thin-film composite (TFC) membranes achieve superior gas separation properties from high-performance selective layer materials, while the success of membrane technology relies on high-performance gutter layers to achieve production scalability and low-cost manufacturing. However, the current literature predominantly focuses on the design of polymer architectures to obtain high permeability and selectivity, while the art of fabricating gutter layers is usually safeguarded by industrial manufacturers and appears lackluster to academic researchers. This is the first report aiming to provide a comprehensive and critical review of state-of-the-art gutter layer materials and their design and modification to enable TFC membranes with superior separation performance. We first elucidate the importance of the gutter layer on membrane performance through modeling and experimental results. Then various gutter layer materials used to obtain high-performance composite membranes are critically reviewed, and the strategies to improve their compatibility with the selective layer are highlighted, such as oxygen plasma treatment, polydopamine deposition, and surface grafting. Finally, we present the opportunities of the gutter layer design for practical applications. [ABSTRACT FROM AUTHOR]

In recent years, additive manufacturing (AM) has played a significant role in various fashion industries, especially the textile and jewelry manufacturing sectors. This review article delves deeply into the wide range of methods and materials used to make intricately designed jewelry fabrication using the additive manufacturing (AM) process. The Laser Powder Bed Fusion (L-PBF) process is examined for its suitability in achieving complex design and structural integrity in jewelry fabrication even with respect to powder metallurgy methods. Moreover, the review explores the use of precious materials, such as gold, silver, copper, platinum, and their alloys in additive manufacturing. Processing precious materials is challenging due to their high reflectivity and thermal conductivity, which results in poor densification and mechanical properties. To address this issue, the review article proposes three different strategies: (i) adding alloying elements, (ii) coating powder particles, and (iii) using low-wavelength lasers (green or blue). Finally, this review examines crucial post-processing techniques to improve surface quality, robustness, and attractiveness. To conclude, this review emphasizes the potential of combining additive manufacturing (AM) with traditional craftsmanship for creating jewelry, exploring the potential future directions and developments in the field of additive manufacturing (AM) for jewelry fabrication. [ABSTRACT FROM AUTHOR]

Transparent flexible display devices have attracted massive attention in recent years owing to their practical applications that can be compatibly adapted to human demand and technological development. Worldwide researchers have studied flexible transparent thin film transistors (TFTs) to qualify them for the backplane component of future transparent and flexible displays. Simplifying the fabrication process of a TFT can be considered a critical need for reducing consumed cost, time, toxic chemicals. In this study, sputtering was utilized as a major fabrication method for manufacturing a transparent oxide TFT device, which demonstrated good mechanical flexibility. A simple surface treatment process was applied to enhance the susceptibility of the sputtered Al 2 O 3 dielectric through multiple coatings of solution processed Al 2 O 3. It is noteworthy that the transparent oxide TFT device exhibits a high optical transparency of 81.12% and good electrical switchability at low operating voltage (3 V) with a decent mobility of 4.37 cm2 V−1 s−1 and proven mechanical durability. [ABSTRACT FROM AUTHOR]

The lithography process in semiconductor dynamic random-access memory (DRAM) fabrication plants (fabs) is usually a major bottleneck, and reticle scheduling is complicated by process-specific constraints such as diversity of the product mix and rapidly changing deadlines. This study proposes a three-phase scheduling framework to solve the multi-objective reticle scheduling problem, reducing capacity loss, maintaining line balance and meeting customer demand. The genetic algorithm (GA) and the technique for order preference by similarity to ideal solution (TOPSIS) are used to optimize the scheduling with a trade-off among the multiple objectives. This study tests the proposed framework based on a real semiconductor DRAM (fab) in Taiwan, which has two unrelated parallel machines in its lithography process. The study finds that the proposed framework results in better scheduling reports, reduced computation times and improvements in the overall performance of lithography equipment. [ABSTRACT FROM AUTHOR]

Collagen, the major structural protein in various tissues, is an ideal material for tissue regeneration. However, the collagen molecules cannot penetrate across the skin barrier due to their large molecular weight. It is necessary to develop new methods of delivery for promoting the collagen‐based therapy. Microneedle patches have been used in drug delivery applications as an alternative to traditional puncture delivery. In this study, the human collagen decorating microneedle patch was developed to deliver the collagen into the skin tissue, as the human‐source collagen can overcome the immunogenicity of animal‐source collagens in regenerative applications. The human collagen is usually limited by its source. Here, the collagen is derived from an allogeneic extracellular matrix expressed by human stem cells in vitro. The collagen was then loaded on the tip of the microneedle to achieve a high‐loading dose and efficient delivery. The experimental results proved that the microneedles were sharp and rigid enough to pierce the skin, which has the potential to be used for subcutaneous tissue regeneration. Moreover, the fabrication process was simple and effective to realize large‐scale production. [ABSTRACT FROM AUTHOR]

Four‐dimensional (4D) printing is an emerging technology for fabricating customizable tissue engineering implants. 4D printed implants with shape memory properties are expected to provide new application opportunities for minimally invasive surgery. A great challenge is to prepare the biodegradable materials with robust mechanical properties for 4D printing ink. Herein, biodegradable thermoplastic polyurethanes (TPUs) based on IPDI, PEG, PCL, and diols with UPy motifs are synthesized. The pendant UPy motifs can dimerize to form physical crosslinking by quadruple hydrogen bonding assembly, accompanying with significant improving the mechanical properties, self‐healing capability and shape memory effect. With an optimal UPy content, the PU‐U2‐25% shows robust mechanical properties and much better shape memory effect compared with the PU‐U2‐0% without UPy. Moreover, the TPUs show a facile processing at relative low temperature approximately 100 °C which avoid degradation at high processing temperature. Combined with the good processability, self‐healing capacity and shape memory effect of the PU‐U2‐25%, we primary demonstrated its 4D printing potential for various specimens. This work proposed a new strategy to design TPUs integrating the merits of linear and pendant physical crosslinking motifs to obtained excellent comprehensive properties, which would develop the 4D printable materials for applications of personalized and minimally invasive treatment. [ABSTRACT FROM AUTHOR]

Vat photopolymerization (VP) additive manufacturing enables fabrication of complex 3D objects by using light to selectively cure a liquid resin. Developed in the 1980s, this technique initially had few practical applications due to limitations in print speed and final part material properties. In the four decades since the inception of VP, the field has matured substantially due to simultaneous advances in light delivery, interface design, and materials chemistry. Today, VP materials are used in a variety of practical applications and are produced at industrial scale. In this perspective, we trace the developments that enabled this printing revolution by focusing on the enabling themes of light, interfaces, and materials. We focus on these fundamentals as they relate to continuous liquid interface production (CLIP), but provide context for the broader VP field. We identify the fundamental physics of the printing process and the key breakthroughs that have enabled faster and higher-resolution printing, as well as production of better materials. We show examples of how in situ print process monitoring methods such as optical coherence tomography can drastically improve our understanding of the print process. Finally, we highlight areas of recent development such as multimaterial printing and inorganic material printing that represent the next frontiers in VP methods. [ABSTRACT FROM AUTHOR]

Bio‐inspired approaches in materials science and systems chemistry are yielding a variety of stimuli‐responsive and dynamic materials that are gradually changing our everyday life. However, the ability to chemically program these materials to exhibit macroscopic higher‐order behaviours such as self‐assembly, contractility, swarming, taxis, chemical communication, or predator‐prey dynamics remains an ongoing challenge. While still in its infancy, the successful fabrication of bio‐inspired materials displaying higher‐order behaviours not only will help bridging the gap between living and non‐living matter, but it will also contribute to the development of advanced materials for potential applications ranging from tissue engineering and biotechnology, to soft robotics and regenerative medicine. Our Mini‐Review will systematically discuss the higher‐order behaviours developed thus far in bio‐inspired systems, namely (i) polymer networks (ii) microbots, (iii) protocells, and (iv) prototissues. For each system it will provide key examples and highlight how the emergent behaviour could be chemically programmed. [ABSTRACT FROM AUTHOR]

Various techniques have been proposed to manufacture prosthetic sockets, which are essential in improving the quality of life among amputees and individuals with special needs. However, the fabrication of prosthetics using the available approaches is uneconomical due to the type of materials utilized during the production, as well as the direct methods that use expensive materials to produce prosthetic parts. Considering this, it is crucial to enhance the direct methods by exploiting cost-effective materials to produce prosthetic parts with desirable behaviors. Therefore, this study aimed to compare the fatigue performance of below-knee (BK) prosthetic sockets manufactured using three different techniques: laminate, direct, and novel. The three sockets specimens were first manufactured. Specimen A was made via the direct method using 4 layers of carbon fiber as the reinforcement and AX140401 as the matrix. Specimen B was also fabricated via the lamination method using 4 layers of carbon fiber as the reinforcement and lamination resin + hardener acrylic as the matrix. Finally, specimen C was made via the direct novel method using 4 layers of carbon as the reinforcement, and the matrix was composed of 20% polyurethane resin (part A: resin, part B: hardener) + 80% acrylic. Subsequently, the pressure distribution at the contact point between the socket and the residual limb was analyzed using the FSOCKET device. Furthermore, the numerical analysis included the distribution of the stress and the highest internal pressure, the number of cycles ascertained through the utilization of the SOLIDWORKS software. Based on the results, the S-N curves for each specimen show that all three specimens behaved similarly. Using the F-socket, the pressure during the patient's walking cycle reached its highest point at 190 kPa. In addition, applying ground reaction force from the bottom of the direct, lamination, and novel BK prosthetic sockets demonstrated the pressure distribution of the part that reacts to the loading condition. The SOLIDWORKS program revealed from the pressure distribution of the three sockets measured a maximum internal pressure of 191 kPa, 193 kPa, and 191 kPa sequentially, which was close to the pressure within the F-socket. Besides, the number of cycles for the direct, lamination, and novel BK prosthetic sockets was 1,332,345, 1,202,345, and 1,203,567 cycles. In summary, all three specimens fabricated via the direct, lamination, and novel methods achieved similar fatigue performance of BK prosthetic sockets. So, the novel BK prosthetic socket wad designed in which fabricated using a new matrix material was considered acceptable, similar to specimens A and B. [ABSTRACT FROM AUTHOR]

Concrete slurry waste (CSW) is an industrial by-product retrieved in large quantities from ready-mix concrete plants. The present work aims to study the feasibility of the incorporation of this residue in the production of concrete to reduce the dilemma of its disposal on huge amounts, decrease the quantities of natural materials used in concrete assembly and produce a lower carbon footprint concrete. Hence, the CSW were divided into three parts, the first part contains the fraction of fine particles (< 80 µm) (residue 1), the second part contains the entire CSW (residue 2) and the third part contains the rest of CSW after the elimination of residue 1 by sieving (residue 3). Then, the introduction of CSW into concrete was achieved, on one hand, by replacing 2, 4, 6, 8 and 10% of cement by residue 1 and, on the other hand, by substituting 5, 10, 15, 20 and 25% of river sand and crushed sand by residues 2 and 3, separately. In order to qualify and analyze the behavior of this residues in the company of other components of concrete, several chemical and physical characteristics of CSW were evaluated. In addition, CSW were characterized by x-ray fluorescence (XRF), x-ray diffraction (XRD), fourier transform infrared spectrometer (FTIR) and scanning electron microscopy (SEM). The various constituents used in the manufacturing of concrete were characterized physically including particle size distribution, fineness modulus, cleanliness of the sand, flattening coefficient, hardness, apparent density and actual density to conclude the formulation used for the development of the specimens. In addition, the properties of fresh and hardened concretes were also investigated, including Abrams cone subsidence, density and compressive strength. The outcome of this study concludes that modest amounts of CSW improve the physical properties of concretes and consequently their compressive strength, especially at 90 days, whatever the type of martial being substituted. Thus, the introduction of residue 1 into the cement must not exceed 2%, the replacement of residue 2 by river and crushed sands can be done at rates up to 5 and 10%, respectively, while the residue 3 can only substitute river sand at a rate up to 10%. [ABSTRACT FROM AUTHOR]

In the Kota stone industries, a huge quantity of unwanted waste is generated during the process of manufacturing stone. This waste is generally in the form of minute particles that are dumped on nearby land and carried away by water and air causing pollution in air, water, and soil. The most appropriate way is to convert this waste into a useful product. The present work comprises of fabrication and characterization of a new class of polymer composite with polyester as the base matrix and micro-sized Kota stone dust as filler material. A series of composites are fabricated at varied contents of micro-sized particulates using the open molding method. The properties explored are mechanical properties and sliding wear properties as a function of filler loading. It is noticed from the experimentation that the inclusion of filler material improves the different mechanical properties of the composites. The hardness of the composite along with the compressive strength improve by 25.37 % and 13.78 % respectively when 40 wt. % of the Kota stone dust is added to the polyester resin. The maximum hardness obtained is 84.2 Shore-D number and the maximum compressive strength of 109.2 MPa is registered. For a filler loading of 30 wt. %, the highest value of tensile strength is 66.2 MPa and that of flexural strength is 73.2 MPa is registered. The sliding wear tests are conducted as per Taguchi's design of experiment following the L25 orthogonal array. It is observed that the Kota stone dust loading is the utmost significant factor, whereas normal load is the least significant factor that administrates the sliding wear rate. The wear loss mechanism is observed under a scanning electron microscope by studying the eroded surface. [ABSTRACT FROM AUTHOR]

A compact two-element Asscher-shaped wideband MIMO antenna system is proposed in this communication. The Asscher-shaped MIMO system consists of a partial ground plane, an Asscher-shaped patch loaded with CSRR. The bandwidth of the antenna is from 2.5 to 6.4 GHz with a notch at 5.7 GHz which covers WLAN (4,6.2 GHz), WiMAX (4, 5.5 GHz), GSMA (3.5 to 4.2 GHz) and Mid band 5G (3.5 to 4.2 GHz). A decoupling structure enhances the isolation between its elements. The fabricated antenna accommodates 35.2 x67.5 x1.6 mm³. The performance of Asscher shaped MIMO antenna is assessed using the S-parameters, radiation pattern, ECC, DG, TARC, MEG, and CCL. The results from simulation and measurement are validated and both accord well. The antenna design involves simple geometry with no intricate process in fabrication. [ABSTRACT FROM AUTHOR]

Among the non-traditional manufacturing processes, electro-thermal based processes are used to machine the difficult to cut materials. Among thermal based unconventional machining processes, laser machining and plasma arc cutting (PAC) are most significant processes that find applications in various industries including aerospace, automotive, shipbuilding, chemical processes equipment manufacturing and fabrication. In this manuscript, the parametric optimization of PAC is extensively reviewed. Bibliometric analysis of PAC was performed using Web of science and Scopus database wherein research publications were analyzed between year of 1961 to 2023. It was observed from the analysis that minimization of energy consumption in thermal based non-conventional machining methods is not extensively studied. Therefore, literature was reviewed to discuss about energy consumption and reduction of energy requirements in laser and PAC machining. [ABSTRACT FROM AUTHOR]

Microfluidic paper-based analytical devices (μPADs) and microfluidic thread-based analytical devices (μTADs) have recently been introduced as a new class of on-site monitoring devices. Creating hydrophilic channels with hydrophobic barriers on papers/threads produces μPADs/μTADs. Fabrication is a crucial step in creating durable μPADs/μTADs that can withstand various liquids and impact the device's performance. Fabrication materials with distinct physicochemical properties allow microfluidic systems with sophisticated functions to be customized for specific applications. We present flexible and low-cost fabrication methods for μPAD and μTAD platforms. Platform designs and fabrications were implemented using a trial-and-error method for various designs with varying parameters. All production methods presented in the method section were used in |PAD production. For comparison studies, only the dipping method was used in μTAD production due to its ease of application. In this study, we tried to reveal the strengths and weaknesses of the production techniques and the resulting microfluidic platforms. A leaching test was performed with water solutions containing red ink. The compatibility of the hydrophobic walls of the platforms was tested with several solvents (isopropanol, methanol, and acetone), deionized (DI) water, and phosphate buffer solution PBS and compared. Patterning paper with polydimethylsiloxane (PDMS), white glue, alkyl ketene dimer (AKD), beeswax, and paraffin are much more flexible and simpler than traditional photoresist-based fabrications. The advantages and disadvantages of fabrication techniques; solvent resistance and wicking behaviors of platforms were discussed in the last part. The fabricated microfluidic platforms can be functionalized and used in many areas where analytical tests are applied. Studies on diversifying channel geometries and increasing resolution need to be continued. It should be investigated which devices can be used to obtain qualitative and quantitative results. To make simple and cheap production techniques suitable for mass production, studies should be carried out from different branches. [ABSTRACT FROM AUTHOR]

Localized electrochemical deposition microadditive manufacturing (AM) (LECD-µAM) technology represents a nontraditional manufacturing method applied for the layer-by-layer fabrication of metal microstructures via a fully automatic feedback mechanism. In terms of material utilization and complex structure formation, the proposed technology exhibits great potential for microstructure fabrication. The LECD-µAM technology introduced in this study involves the reduction of metal cations in the electrolyte to form metal microstructures. This study showed the flow simulation of an electrolyte in the cantilever probe and pressure distribution at the probe tip. In addition, the effect of extrusion pressure on the deposition structure was investigated experimentally. Combined with the experimental results, we discussed the effects of LECD-µAM technology on deposition outcomes and optimized parameters and designed a printing route for the deposition of complex metal microstructure arrays with smooth surfaces. The proposed technology attained a deposition rate and a microstructural copper content of 0.961 µm/s and 99.5%. In addition, LECD-µAM technology can be performed at room temperature, has low environmental requirements and cost, provides a good deposition surface, and holds great potential for the manufacture of three-dimensional and other complex microstructure arrays. Highlights: The technology realizes micron level complex structure additive manufacturing based on the hollow atomic force microscopy (AFM) cantilever probe. By designing the deposition path, adjust the extrusion pressure to control the deposition structure. The proposed technology attained a deposition rate and a microstructural copper content of 0.961 µm/s and 99.5%. It has the characteristics of faster speed and higher purity. [ABSTRACT FROM AUTHOR]

The healing of damaged skin is a complex and dynamic process, and the multifunctional hydrogel dressings could promote skin tissue healing. This study, therefore, explored the development of a composite multifunctional hydrogel (HDCP) by incorporating the dopamine modified hyaluronic acid (HA-DA) and phenylboronic acid modified chitosan (CS-PBA) crosslinked using boric acid ester bonds. The integration of HA-DA and CS-PBA could be confirmed using the Fourier transform infrared spectrometer and 1H nuclear magnetic resonance analyses. The fabricated HDCP hydrogels exhibited porous structure, elastic solid behavior, shear-thinning, and adhesion properties. Furthermore, the HDCP hydrogels exhibited antibacterial efficacy against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). Subsequently, the cytocompatibility of the HDCP hydrogels was verified through CCK-8 assay and fluorescent image analysis following co-cultivation with NIH-3T3 cells. This research presents an innovative multifunctional hydrogel that holds promise as a wound dressing for various applications within the realm of wound healing. [ABSTRACT FROM AUTHOR]

Recently, the challenges pertaining to the recycling of metal-based electrode materials and the resulting environmental pollution have impeded the advancement of battery technology. Consequently, biomass-derived carbon materials, distinguished by their eco-friendliness and consistent performance, stand as a pivotal solution to this predicament. Researchers have made significant strides in the integration of porous carbon materials derived from biomass into battery systems. Nevertheless, these materials face issues such as limited efficiency, modest yields, and a complex fabrication process. This paper endeavors to summarize the recent advancements in the utilization of biomass-derived carbon materials within the realm of batteries, offering a comprehensive examination of their battery performance from three distinct perspectives: synthesis, structure, and application. We posit that composite materials composed of biomass-derived carbon align with the trajectory of future development and present extensive potential for application. Ultimately, we will expound upon our profound outlook regarding the furtherance of biomass-derived carbon materials. [ABSTRACT FROM AUTHOR]

With increasing digitalization in orthodontics, certain orthodontic manufacturing processes such as the fabrication of indirect bonding trays, aligner production, or wire bending can be automated. However, orthodontic treatment planning and evaluation remains a specialist's task and responsibility. As the prediction of growth in orthodontic patients and response to orthodontic treatment is inherently complex and individual, orthodontists make use of features gathered from longitudinal, multimodal, and standardized orthodontic data sets. Currently, these data sets are used by the orthodontist to make informed, rule-based treatment decisions. In research, artificial intelligence (AI) has been successfully applied to assist orthodontists with the extraction of relevant data from such data sets. Here, AI has been applied for the analysis of clinical imagery, such as automated landmark detection in lateral cephalograms but also for evaluation of intraoral scans or photographic data. Furthermore, AI is applied to help orthodontists with decision support for treatment decisions such as the need for orthognathic surgery or for orthodontic tooth extractions. One major challenge in current AI research in orthodontics is the limited generalizability, as most studies use unicentric data with high risks of bias. Moreover, comparing AI across different studies and tasks is virtually impossible as both outcomes and outcome metrics vary widely, and underlying data sets are not standardized. Notably, only few AI applications in orthodontics have reached full clinical maturity and regulatory approval, and researchers in the field are tasked with tackling real-world evaluation and implementation of AI into the orthodontic workflow. [ABSTRACT FROM AUTHOR]

LED devices are increasingly gaining importance in lithography approaches due to the fact that they can be used flexibly for mask-less patterning. In this study, we briefly report on developments in mask-free lithography approaches based on nano-LED devices and summarize our current achievements in the different building blocks needed for its application. Individually addressable nano-LED structures can form the basis for an unprecedented fast and flexible patterning, on demand, in photo-chemically sensitive films. We introduce a driving scheme for nano-LEDs in arrays serving for a singularly addressable approach. Furthermore, we discuss the challenges facing nano-LED fabrication and possibilities to improve their performance. Additionally, we introduce LED structures based on a hybrid nanocrystal/nano-LED approach. Lastly, we provide an outlook how this approach could further develop for next generation lithography systems. This technique has a huge potential to revolutionize the field and to contribute significantly to energy and resources saving device nanomanufacturing. [ABSTRACT FROM AUTHOR]

Aerogels have emerged as appealing materials for various applications due to their unique features, such as low density, high porosity, high surface area, and low thermal conductivity. Aiming to bring the advantages of these materials to the environmental field, this study focuses on synthesizing magnetic silica aerogel-based films suitable for water decontamination. In this respect, a novel microfluidic platform was created to obtain core-shell iron oxide nanoparticles that were further incorporated into gel-forming precursor solutions. Afterward, dip-coating deposition was utilized to create thin layers of silica-based gels, which were further processed by 15-hour gelation time, solvent transfer, and further CO2 desiccation. A series of physicochemical analyses (XRD, HR-MS FT-ICR, FT-IR, TEM, SEM, and EDS) were performed to characterize the final films and intermediate products. The proposed advanced imaging experimental model for film homogeneity and adsorption characteristics confirmed uniform aerogel film deposition, nanostructured surface, and ability to remove pesticides from contaminated water samples. Based on thorough investigations, it was concluded that the fabricated magnetic aerogel-based thin films are promising candidates for water decontamination and novel solid-phase extraction sample preparation. [ABSTRACT FROM AUTHOR]

Additive manufacturing has emerged as a transformative methodology in numerous engineering domains, with the fabrication of antennas and electromagnetic devices being a promising application area. This study presents a comprehensive review of the application of these technologies for manufacturing electromagnetic devices, offering a categorized analysis based on different types of additive manufacturing techniques. Each category is examined, and its characteristics are briefly described, highlighting not only the most innovative and significant devices fabricated using specific technologies, but also identifying their limitations and strengths. Through a dual analysis, this paper provides a deep understanding of the potential of and challenges associated with using different additive manufacturing technologies in the design and crafting of electromagnetic components. Moreover, this review offers recommendations for future studies, suggesting how the unique features of this new manufacturing paradigm could be further leveraged for breakthroughs in the electromagnetic field. [ABSTRACT FROM AUTHOR]

Fused Filament Fabrication (FFF) is a 3D (three-dimensional) printing technology that allows the production of polymers with a wide range of infill densities and unlimited geometric variations. Because of this flexibility, mechanical properties can be optimized by tuning printing parameters. However, the energy consumption during fabrication varies significantly for different printing settings. In the present study, both maximum fracture force and minimum energy consumption of 3D printed PLA (Polylactic Acid) are achieved together by optimizing the printing parameters using CPA (Cyclical Parthenogenesis Algorithm) optimization algorithm. Firstly, a quasi-static penetration test is performed to measure the maximum fracture force. The energy consumption of each specimen is also calculated. Then, maximum fracture force and energy consumption are modeled and integrated into the optimization algorithm. As a result, the three most convenient parameter levels are 84%, 6.83 mm, and 0.19 mm for infill ratio, specimen thickness, and layer height, respectively. While high infill ratio values and specimen thickness increase mechanical performance, these parameter levels are disadvantageous for energy consumption. As a result of optimization, parameters that provide balanced strength and energy consumption were obtained. Fracture force and energy consumption are 1829.87 N and 134.56 W, respectively for the validation experiment of the optimal solution. [ABSTRACT FROM AUTHOR]

Additive manufacturing has advantages over other traditional manufacturing technologies for the fabrication of complex thin-walled parts. Previous correlation path strategies, when applied to laser metal deposition processes, suffer from contour deposition transboundary and surface "scar" type overstacking. Therefore, this paper proposes a hybrid path generation method for the laser metal deposition process. First, the topological logic of the STL model of the part is restored to reduce redundant calculations at the stage of obtaining the layered contour. Then, the path points are planned on the basis of the offset contours in a helical upward trend to form a globally continuous composite path in space considering the melt channel width. Finally, vectors that adaptively fit to the model surface are generated for the path points as tool orientations and they are optimized by smoothing the rotation angles. The results of experiments conducted on a multi-axis machine equipped with a laser metal deposition module show that the path generated by the proposed method is not only capable of thin-walled structures with overhanging and curved surface features but also improves the surface imperfections of the part due to sudden changes in the angle of rotation while ensuring the boundary dimensions. [ABSTRACT FROM AUTHOR]

Piezoelectric materials are used for various commercial and strategic applications. For most of the current generation applications the usage temperature is about 150°C and therefore, ceramics like lead zirconate titanate or lead-free ceramics such as potassium sodium niobite which exhibit Curie temperature (TC) in between 350° and 450°C are useful. However, in the next-generation applications, the usage temperature is expected to be more than 500°C. As a thumb rule usage temperature of a ferroelectric ceramic is ½ of TC and hence, ceramics with a TC greater than 1000°C are required for such applications. Perovskite layer structure (PLS) piezoceramics exhibit TC well above 1000°C and thus, are the most promising materials for high temperature piezoelectric applications. With this background, we review the synthesis, fabrication and structural aspects of the PLS piezoceramics. We also discuss the peculiar microstructure and dielectric properties of these ceramics along with their advantages and limitations. [ABSTRACT FROM AUTHOR]

Additive manufacturing technology has fostered its significant application in soft robotics fabrication due to the design freedom and ease of realizing complex geometries. The selection of an appropriate additive manufacturing process (out-of-material extrusion, vat photopolymerization, and powder bed fusion) is vital for the fabrication of soft robotics as the process greatly influences the quality of the part further affecting the functionality and service life. These pneumatically actuated robots in their service life are subjected to fatigue loading and handling of very delicate tasks; thus, the porosity (including pores characterization) and surface roughness are two critical quality parameters which should be considered while choosing the fabrication process. In this study, a three-way decision-making (a multi-criteria decision-making tool) approach is implemented for selecting an appropriate additive manufacturing process for the fabrication of high-quality parts for soft robotics applications. The results (ranking of AM processes) obtained using the proposed approach are compared with the conventional decision-making techniques, namely TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution), MOORA (Multi-Objective Optimization by Ratio Analysis), and VIKOR (VIseKriterijumska Optimizacija). The sensitivity analysis carried out in this work also suggests that three-way decision-making is as effective as other MCDM tools and the vat photopolymerization process is the most suitable out of all for fabricating TPU actuators. [ABSTRACT FROM AUTHOR]

Coastal biogenic structures, formed by ecosystem engineering species, often feature rough surfaces characterized by intricate topographies and highly threedimensional reliefs. Their surfaces are shaped by waves and tidal currents and reciprocally influence the ambient hydrodynamics, reflecting an equilibrium. Despite their significance, the impact of these surfaces on the ambient hydrodynamics remains underexplored due to limited knowledge of accurately replicating their complex topographies in experimental setups. The recent advent of advanced digital manufacturing presents an efficient means to manufacture highly complex, three-dimensional surrogate models for experimental modeling. This work explores the accurate replication of rough coastal biogenic structures for experimental modeling on the examples of an oyster reef and a mussel bed, utilizing a flexible design methodology and, for the first time, particle bed 3D printing with Selective Cement Activation (SCA) as a fabrication and manufacturing method. A workflow is proposed, which includes an iterative surrogate model development based on in-situ topographical features, requirements of the experimental setup, and parameters of the particle bed 3D printer with SCA. The results demonstrate the effectiveness of the methodology in achieving highly accurate surrogate surfaces of complex coastal biogenic structures by validation against a set of topographical features relevant to hydraulic roughness. Particle bed 3D printing with SCA proved to be a suitable method to manufacture complex surrogate surfaces for experimental modeling, offering advantages such as independence of production time from surface complexity. However, challenges persist in achieving exact comparability between the manufactured surrogate surface and the real coastal biogenic structures, particularly for surfaces with very high complexity. Nonetheless, the manufactured generic surrogate surfaces enable detailed investigations into the influence of complex coastal biogenic structures on the ambient hydrodynamics, thereby enhancing the understanding of the processes governing wave energy dissipation attenuation, turbulence production, and vertical mixing - critical for efficient application as a nature-based solution on coastal protection or restoration efforts. [ABSTRACT FROM AUTHOR]

Powder bed fusion (PBF) is an attractive additive manufacturing option for fabrication of SiC object with complex geometries. However, the density and microstructure controls remain a challenge. This study is aimed at understanding laser–SiC interactions, with emphasis on microstructure‐processing relationships, to identify potential solutions for the process improvement. SiC tubes were fabricated by PBF of pure SiC powders without sintering additives. Comprehensive analysis by X‐ray diffraction, Raman spectroscopy, and electron microscopy indicated that binding of SiC particles was achieved by incongruent melting of SiC to a Si/C mixture containing SiC micro‐ and nanocrystallites. The phase evolution under laser irradiation of SiC was explained by phase diagrams. This study uncovered the PBF SiC microstructure at different length scales and the relationship between the microstructure and the processing parameters. [ABSTRACT FROM AUTHOR]

Wearable electrochemical sensors, which can track various biomarkers in real‐time, is one of the most promising bioanalytical devices in the point of care testing and health management. Sample collection modules, as the important front‐end of the sensors, capture and transfer enough sample so as to achieve real‐time, precise and accurate detection. Noninvasive and minimally invasive techniques for sample collection are highly desired. However, it is still a key challenge to realize a reliable sample acquisition. Herein, we provide an overview on the progress in the sample collection methods for wearable electrochemical sensors. It covers the conventional and emerging methods/structures including reverse iontophoresis, microneedles, as well as microfluidic chips. The working principle, fabrication materials and manufacturing technologies will be introduced in detail. Finally, the present challenges and the development trend in the future of these approaches are also put forward. [ABSTRACT FROM AUTHOR]

This study is a digital form-finding and manual fabrication experiment in woven architectural design, with one traditional weaving style, Kagome, used to scale the craft up into an architectural-scale bamboo woven artifact. Kagome is a trihexagonal pattern employed in traditional bamboo basketry as a triaxial weaving system, resulting in an object with a self-bracing capacity without the use of fasteners owing to its interlacing lattices. Although existing studies and tools have addressed triaxial weaving design and representation, the current consideration of the advantages of weaving with bamboo is insufficient. To address this research gap, this study develops a computational design method based on studies on bamboo basketry. This allows for the representation and exploration of design geometries using combinations of regular triangular meshes for the fabrication of Kagome woven bamboo artifacts. A full-scale mock-up was fabricated to evaluate the effectiveness of the method. The mock-up demonstrated the self-bracing properties of Kagome, but there were discrepancies between the mock-up and the design. Factors affecting bamboo weaving on an architectural scale have been identified within this study to inform future research on woven bamboo structures. [ABSTRACT FROM AUTHOR]