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This article provides a proof of concept on how Surface-enhanced Raman Scattering (SERS) can be combined with microfluidics towards the development of an in situ chemical detection method. A microfluidic device prototype was designed, fabricated, and characterized to demonstrate the feasibility of microfluidics in achieving analyte transport from the sample introduction site to the detection site. Subsequently, the microfluidic setup was used for monitoring the adsorption kinetics of the molecule rhodamine 6G (R6G) onto a SERS-active substrate; an application, for which only scare information is available in the literature. Moreover, this work demonstrates how the actual concentration of adsorbed R6G (moles m-2) onto the SERS substrate can be quantified in real time. SERS-active substrates, such the ones used in this study, can be integrated in a microfluidic device for achieving reproducible monitoring of the adsorption kinetics of a molecule in a liquid sample, or for detecting and reporting the concentration of an unknown target molecule during a diagnostic assay. [ABSTRACT FROM AUTHOR]

Aim: The purpose of this in vitro study was to comparatively evaluate the marginal and internal fits of cobalt– chromium metal custom post and core fabricated using a conventional technique with two digital techniques. Settings and Design: The study was designed in an in-vitro study setting. Materials and Methods: Five sets of custom post and core restorations were fabricated using the conventional (Group 1) and two semi digital methods (digital scanning of the resin pattern and computer aided additive manufacturing, and digital scanning of the silicone impression and subsequent computer aided designing [CAD] computer aided manufacturing fabrication) (Group 2 and 3). Marginal and internal fits of the posts were evaluated using a micro computed tomography scan at various points. Statistical Analysis Used: A one way ANOVA test of the scores was made to evaluate the effect of different methods of custom post and core fabrication on marginal and internal fits. Bonferroni adjusted post hoc tests were conducted for intergroup comparison. Results: Least marginal gap was reported in Group 3 (82.5 ± 14.36 μm) followed by Group 1 (110 ± 25.19 μm) and Group 2 (112.5 ± 26.75 μm). Least internal gap at cervical, middle and apical as well as overall values were observed in Group 3 (78 ± 9.25 μm, 72 ± 7.79 μm, 160 ± 15.81 μm, 103.3 ± 4.43 μm) followed by Group 1 (113.5 ± 25.35 μm, 132.5 ± 19.92 μm, 502 ± 74.63 μm, 249.3 ± 25.44 μm) and Group 2 (114.5 ± 21.68 μm, 133.5 ± 19.57 μm, 598 ± 87.86 μm, 282 ± 28.91 μm) respectively. The results of one-way ANOVA and Bonferroni adjusted post hoc tests for marginal gap did not show any statistically significant difference between the three groups (P > 0.05) but revealed statistically significant difference (P = 0.02) in internal gap values at the cervical, middle, and apical regions as well as overall internal gap region between the three groups. Conclusions: Better marginal and internal fits were observed in custom post and core fabricated by digital scanning of the silicone impression and subsequent CAD as compared to those fabricated by the other two groups. [ABSTRACT FROM AUTHOR]

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Numerical simulations play a pivotal role in advancing fabrication processes and welding technologies, enabling the pursuit of sustainable practices. By employing the finite element method, crucial insights regarding welded specimens can be derived, encompassing deformed shapes, residual stresses, and even microstructural properties such as phase proportions and hardness. This study focuses on the modeling framework of welding processes, emphasizing the influence of various welding parameters on sustainable outcomes, including reduced environmental impact and enhanced resource efficiency. The investigation delves into the characterization of heat sources, accounting for temperature-dependent material properties and developing a comprehensive thermo-mechanical analysis. By incorporating sustainability considerations and utilizing our Finite Element (FE) model, we conducted further analysis to elucidate the stability behavior, aligning with sustainable objectives. By considering welding current, arc voltage, and welding speed as random variables with mean values and standard deviations, the study aims to identify a model that effectively accounts for the inherent randomness of the welding process. This research contributes to the growing body of knowledge on sustainable welding practices by merging numerical simulations, advanced modeling techniques, and sustainability principles. The outcomes of this study have the potential to inform industry stakeholders and decision-makers about the most effective strategies for achieving sustainable welding processes and minimizing the ecological footprint of the welding operations. [ABSTRACT FROM AUTHOR]

This research aims to investigate and analyze the implementation of marketing plans at Abrasion Resistance Plate stockist and steel fabrication companies in Indonesia. Abrasion Resistance Plate is a material that is needed in various industries, especially in construction and manufacturing, because of its extraordinary wear-resistant properties. Implementation of an effective marketing plan can be a key factor in a company's success in a competitive market. This study was conducted by analyzing the marketing strategies used by companies in marketing their Abrasion Resistance Plate products. The research methodology involved analysis of primary and secondary data, including interviews with company management, customer surveys, and literature reviews. The results of this research provide in-depth insight into the marketing strategies used by this company, including market segmentation, pricing, promotion, and distribution. The findings of this research will provide valuable guidance for similar companies in the Abrasion Resistance Plate steel industry and also contribute to a better understanding of the dynamics of the steel market in Indonesia. Apart from that, the results of this research can also be a basis for these companies to improve and optimize their marketing plans in order to increase their competitiveness in the market. [ABSTRACT FROM AUTHOR]

A co‐continuous 50:50 blend of poly(lactic acid) (PLA) and poly(butylene adipate‐co‐terephthalate) (PBAT) was compounded with 10–40 wt% hemp hurd microparticles (<250 μm) to achieve balanced material properties for additive manufacturing (3D printing) applications. The blend and composites were further compatibilized with maleic anhydride via an in situ reactive extrusion process to enhance the adhesion between the polymers and the fillers and subsequently improve stress transfer between the components. All composite samples were processed further via injection molding and 3D printing processes to analyze and compare the rheology, morphology, thermal, mechanical properties, and other physio‐chemical properties. For the unfilled polymer blends, the injection molded and 3D printed sample specimens displayed similar mechanical properties. However, in the hemp filled composites, the injection molded specimens demonstrated enhanced mechanical properties. This indicates that the 3D printing process requires further parameter optimization to eliminate potential gaps between the printing layers and enhance mechanical properties. Overall, the PLA:PBAT blends filled with hemp hurd microparticles provided balanced composite properties in addition to their sustainability attribute, which makes them an appealing alternative for the fabrication of compostable and tough materials via additive manufacturing processes. Highlights: Upon maleation, the blend components formed a co‐continuous morphology.Sustainable plastic filament with up to 40 wt% hemp hurd micro particles.3D printing can compete with injection molding in filled composites.Successfully 3D printed model furniture with 30 wt% hemp filler. [ABSTRACT FROM AUTHOR]

Additive manufacturing transforms the industry by integrating innovative and intelligent technology, resulting in less material waste and faster prototyping. However, qualitative ambiguities are a significant barrier to digital fabrication methods to manufacture essential parts that require great precision and accuracy. However, qualitative ambiguities are a substantial barrier to digital fabrication methods to manufacture crucial parts that demand higher precision and accuracy. As a result, process monitoring techniques during production are becoming increasingly important. Acoustic emission testing is a prominent nondestructive testing approach that has demonstrated its capacity to detect and locate minute and internal developing cracks, allowing for real-time damage monitoring. This study briefly discussed different additive manufacturing processes, their influential parameters, and monitoring techniques, with particular emphasis on acoustic emission techniques. This study provides extensive recommendations for process monitoring of fused deposition modeling, powder bed fusion and directed energy deposition methods using acoustic emission testing. The different approaches used for handling the acoustic emission data and the effect of defects on acoustic emission signal parameters are also reviewed in this study. [ABSTRACT FROM AUTHOR]

Untethered soft fiber actuators are advancing toward next‐generation artificial muscles, with rotating polymer fibers allowing controlled rotational deformations and contractions accompanied by torque and longitudinal forces. Current approaches, however, are based either on non‐recyclable and non‐reprogrammable thermosets, exhibit rotational deformations and torques with inadequate actuation performance, or involve intricate multistep processing and photopolymerization impeding scalable fabrication and manufacturing of millimeter‐thick fibers. Here, the melt‐extrusion and drawing of a 50 m long thermoplastic liquid crystal elastomer fiber with a ≈1.3 mm diameter on a large scale is reported. With the responsive thermoplastic material, rotating actuators are fabricated via easily exploited programming freedom resulting in large, reversible rotational deformations and torques. The actuation performance of the twisted fibers may be controlled by the programmed twisting density without complicated preparation steps or photocuring being required. The thermoplastic behavior enables fabrication of plied fibers, demonstrated as a triple helical twisted rope constructed from individual rotating fibers delivering up to three times as great rotational and longitudinal forces capable of reversibly opening and lifting a screw cap vial. Besides the programmability, the thermoplastic material employed lends itself to be completely reprocessed into other configurations with self‐healing properties in contrast to thermosets. [ABSTRACT FROM AUTHOR]

Through the active control of shield thrust system oil pressures, a synchronous shield tunnelling technology combining advancement and segment fabrication was proposed. The key to this technology was to completely exploit the additional stroke of the hydraulic jacks generated by the axial insertion of a key block to assemble the segments. Taking the tunnelling project of the Shanghai Airport Railway Link Line as a demonstration project, this paper uses a large model test platform for this synchronous technology. A single-ring construction process along a straight line was simulated, in which the theoretical external loads were implemented on the shield machine. The feasibility and reliability of this synchronous technology were evaluated considering the accuracy of total thrust force control, maintenance of tunnelling speed and shield postures and segment compression. The effectiveness of the redistribution principle for the missing thrust force due to the withdrawal of cylinders located in the segment fabrication region was discussed. Furthermore, some other interesting phenomena were observed in the practical application in addition to the model test. This technology primarily realizes synchronous assembly by improving the control of the propulsion system of conventional shield machines without any transformation of the shield machine's primary structure, segment patterns or excavation method. The proposed method has good adaptability and a low construction cost, which will be beneficial for future long-distance tunnelling projects. [ABSTRACT FROM AUTHOR]

Investigation of a new process and method to control the planarity of thin-walled parts can provide an important theoretical and application foundation for the high-precision, high-quality fabrication of thin-walled components in aerospace and other areas. A planarity control method based on ice fixation for the milling of thin-walled parts is proposed for thin-walled aluminum alloy 7075 flat parts. The heart of the method is the application of a low temperature of about -5 °C to a flat thin-walled part using a freezing tray to hold the workpiece in place in order to control the flatness of the thin wall face grinding process. Investigation of the influence of the machining process and workpiece shape parameters on the machining flatness of thin-walled parts was conducted based on the practicality and efficiency of the method. Experimental results demonstrate that: compared to traditional milling (non-ice fixation), this method of fixing the ice can significantly improve the milling flatness of thin-walled parts, with the reduction of flatness ranging from 16.4% to 60.0%; however, the reduction of flatness is accompanied by the phenomenon of increasing milling force, with the mean increase in milling strength ranging between 5.8% and 40.3%; the flatness of the machining process decreases with increasing workpiece thickness (15.6%--65.0%) and increases with an increasing aspect ratio of the workpieces (17.4%--48.7%). The orthogonal test results show that the best-machined flatness can be achieved at large spindle speed, high feed rate, and low cutting depth working conditions, i.e. spindle speed 3000r⋅min-1, feed rate 350 mm ⋅ min-1, and cutting depth 0.01 mm. [ABSTRACT FROM AUTHOR]

The use of wickless heat pipe heat exchangers has been improving a wide range of thermal applications such as solar water heaters. Therefore, more scientific research needs to be conducted to improve its performance. In the present study, a wickless heat pipe heat exchanger test rig has been designed and fabricated to investigate the effect of different parameters on its performance. Two different heat pipe working fluids have been used namely pure water and water with nanoparticles (Al2O3) using different fluid volume ratios (20%,40%,60%,80%, and 100%). The concentrations of the nanoparticles in water range between 1.3 and 7 % wt. For the heat exchanger, various inlet hot air temperatures (50, 55, and 60 ℃) have been tested at the hot side (heat pipe evaporator) whereas the inlet temperature of the cold side (heat pipe condenser) has been maintained at 20 ℃. The effect of airflow Reynolds number has also been examined with a range of 2583-20664. Results showed that the best heat exchanger effectiveness is achieved at a Reynolds number of 10332 and nanoparticles concentration of 7% wt. Also, the use of nanoparticles reduced the thermal resistance in the heat pipe due to the significant reduction in its surface temperature compared to that of pure water. [ABSTRACT FROM AUTHOR]

Synthetic phantoms that recreate the characteristics of biological tissues are valuable tools for systematically studying and comprehending physiologies, pathologies, and biological processes related to tissues. The reproduction of mechanical and optical properties allows for the development and evaluation of novel systems and applications in areas such as imaging, optics, ultrasound, or dosimetry, among others. This paper proposes a methodology for manufacturing agarose-based phantoms that mimics the optical properties of healthy brain tissue within the wavelength infrared range of 800 to 820 nm. The fabrication of such phantoms enables the possibility of testing and experimentation in controlled and safe environments toward the design of new near-infrared multispectral imaging systems in neurosurgery. The results of an experimental optical characterization study indicate the validity and reliability of the proposed method for fabricating brain tissue phantoms in a cost-effective and straightforward fashion. [ABSTRACT FROM AUTHOR]

Because of the pronounced degradation of the environment, there has been an escalated demand for the fabrication of eco-friendly and highly efficient products derived from renewable sources. Cellulose aerogels have attracted significant interest attributable to their structural characteristics coupled with biodegradability and biocompatibility. The features of the molecular structure of cellulose allow for the use of various methods in the production of gels. For instance, the presence of hydroxyl groups on the cellulose surface allows for chemical crosslinking via etherification reactions. On the other hand, cellulose gel can be procured by modulating the solvent power of the solvent. In this study, we investigate the impact of the gelation methodology on the structural attributes of aerogels. We present methodologies for aerogel synthesis employing three distinct gelation techniques: chemical crosslinking, cryotropic gelation, and CO2-induced gelation. The outcomes encompass data derived from helium pycnometry, Fourier-transform infrared spectroscopy, nitrogen porosimetry, and scanning electron microscopy. The resultant specimens exhibited a mesoporous fibrous structure. It was discerned that specimens generated through cryotropic gelation and CO2-induced gelation manifested higher porosity (93–95%) and specific surface areas (199–413 m2/g) in contrast to those produced via chemical crosslinking (porosity 72–95% and specific surface area 25–133 m2/g). Hence, this research underscores the feasibility of producing cellulose-based aerogels with enhanced characteristics, circumventing the necessity of employing toxic cross-linking agents. The process of gel formation through chemical crosslinking enables the creation of gels with enhanced mechanical properties and a more resilient structure. Two alternative methodologies prove particularly advantageous in applications necessitating biocompatibility and high porosity. Notably, CO2-induced gelation has not been hitherto addressed in the literature as a means to produce cellulose gels. The distinctive feature of this approach resides in the ability to combine the stages of obtaining an aerogel in one apparatus. [ABSTRACT FROM AUTHOR]

Nanomaterials have been used in catalytic degradation of organic pollutants also act as catalysts in for many years. Due to excellent catalytic performances of metal-based nanoparticles, these materials have been used extensively in various hybrid catalyst synthesis. The main subject of this study, heterogeneous catalysis is a low cost and multi-purpose process for many pollutants. Catalytic degradation of organic pollutants such as; 2-nitrophenol, quinolin yellow and rhodamine B was investigated by using Ni, Co, Pd nanoparticles modified SiO2 based nanomaterials. The co-doping effect on the prepared nanomaterials has been investigated with different characterization methods in terms of structural and morphological features: scanning electron microscopy, UV/vis absorption spectroscopy, energy-dispersive X-ray spectroscopy and foruier-transform infrared spectroscopy. The highest catalytic reduction efficiencies (97.6% and 97.5%) for 2-nitrophenol and rhodamine B was obtained by Pd-PEG-AP@SiO2 respectively. The synthesized Co-PEG-AP@SiO2 illustrated higher catalytic reduction efficiency for quinolin yellow (70.1%) at the end of 60s. The prepared M-PEG-AP@SiO2 nanomaterial (M: Pd,Co,Ni) can be able to utilized degradation of organic contaminants effectively. [ABSTRACT FROM AUTHOR]

In this research, MgF2 and SiO2 thin films were prepared by the magnetron sputtering method on glass and ITO substrates. The crystal structure, morphology, and antireflection performance of the coatings were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and ultraviolet spectrophotometry (UV-vis) techniques, respectively. Furthermore, by utilizing both experimental characterization and optical film design tools, the best experimental parameters for every coating were identified. FESEM images confirmed proper growth of the layers on the substrates. EDAX analysis revealed that the manufactured layer consisted of Magnesium fluoride and silica. The study of optical properties demonstrated that the average transmission in the 400-1000 nanometer range exceeded 99%, indicating good agreement with theoretical results. Furthermore, the use of ITO as the substrate reduced the bandgap. [ABSTRACT FROM AUTHOR]

Additive manufacturing is a fabrication technique where materials are built up layer-by-layer allowing the realization of complex designs. Ceramic additive manufacturing is steadily increasing in the market and industries are developing 3D printers that are economical and efficient to print single/multi-material. The development of free-form extrusion-type printers has been of great significance due to their wide range of materials used, availability of technology, low development cost, and design freedom in developing the structures. We have successfully developed a hybrid multi-head 3D printer with four print heads capable of operating individually or together to print multiple layers using different materials. The three mechanically actuated print heads are provided to print ceramic, metallic slurry, and polymeric materials, and one pneumatic actuated print head is for printing bio-ink. The developed hybrid multi-head 3D printer can be beneficial in printing a wide range of materials such as metals, ceramics, polymers, and composites due to its flexibility in printing materials of different viscosities at different pressure. The optimization of the printing of calcium silicate bio-ceramics and multi-material is also studied and reported. [ABSTRACT FROM AUTHOR]

Total hip arthroplasty (THA) involves the replacement of damaged or worn‐out hip components with artificial implants. Frequently revision surgeries were performed due to the failure of the implant. The liners are the ones that are replaced in the majority of the revision surgeries. Researchers are constantly finding different materials to overcome the difficulties being faced. The acetabular liners are fabricated by compression molding and milling using single materials such as Polyethylene, Polyether–ether–ketone (PEEK), and recently Ultra‐High Molecular Weight Polyethylene (UHMWPE), and so forth. Poly Lactic Acid (PLA) being biocompatible and cheaper than UHMWPE is employed in the research. The biodegradable nature of PLA is countered by introducing a nonbiodegradable yet biocompatible High Impact Polystyrene (HIPS). This research attempts to propose and fabricate a novel design of the liner with PLA sandwiched between HIPS by fused filament fabrication, the widely used additive manufacturing technique. The dimensional accuracy and surface roughness of the liners are measured and compared with single‐material liners. The multi‐material liner demonstrated superior dimensional accuracy compared to PLA liner and also exhibiting a smoother surface finish. Dynamic Mechanical Analysis is conducted to determine the capability of printing and also the scanning electron microscopic (SEM) images are used for supporting the results. Highlights: Novel design of Acetabular Liner.Use of additive manufacturing for fabrication of implant parts.More than one material used to reap benefits from the two materials used.Measurement of dimensional accuracy, surface roughness of multi‐material liner.Comparison of single and multi‐material liner. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the failure load of 3D-printed denture resin material and teeth before and after dynamic loading. Materials and Methods: A total of 40 specimens were fabricated following ISO/TS 19736 and were divided into two equal groups. In the test group, the cylindrical base and denture teeth were 3D printed separately and then luted together. In the control group, the specimens were fabricated from conventional heat-cured polymethyl methacrylate (PMMA) and commercially available denture teeth using the compression-molding technique. Ten specimens from each group were subjected to a dynamic load of 50 N for 250,000 cycles in a chewing simulator. All specimens were subjected to a static load of 50 N using an Instron machine with a crosshead speed of 1 mm/minute until fracture. The fractured surfaces were analyzed using field emission scanning electron microscopy. The failure loads were calculated and compared using analysis of variance (P < .05). Results: All specimens survived the loading, undergoing 250,000 cycles without fracture. The mean failure load was influenced by fabrication technique and was significantly higher for the 3D-printed test group (P = .028). 3D-printed teeth showed a mixed mode of fracture, whereas in the control group, the specimens showed cohesive fracture within the teeth. Conclusion: The fabrication technique has an influence on the mode of failure between the acrylic teeth and resin base material. Cohesive failure in teeth was predominant in the conventional group, suggesting possibly higher bond strength between the teeth and resin base in this group. The observed failure modes revealed that both fabrication techniques exhibit satisfactory bond strength. Chewing simulation did not significantly influence the bond strength of any of the tested groups. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the impact of high-speed sintering on the accuracy (ie, trueness and reproducibility) and fit of yttria-stabilized tetragonal zirconia polycrystal (4Y-TZP) full-coverage single-unit fixed dental prostheses (FDPs) and three-unit FDPs. Materials and Methods: Single-unit FDPs, conventional three-unit FDPs, and cantilever three-unit FDPs (N = 108; n = 12 per subgroup) were fabricated from: (1) high-speed-sintered (1,580°C, about 20 minutes) multi-layer 4Y-TZP (Zolid RS [ZMLH]), as well as two conventionally sintered (1,450°C, about 10 hours) materials: (2) multi-layer 4Y-TZP (Zolid Gen-X [ZMLC]) and (3) monochrome 4Y-TZP (Ceramill Zolid HT+ PS [ZMOC]). All specimens were scanned, and trueness, reproducibility, and fit were measured with 3D analysis software. For data analysis, Kolmogorov-Smirnov, Kruskal-Wallis, and Mann-Whitney U tests were performed (a = .05). Results: Three-unit FDPs made from ZMLH presented a deterioration of accuracy in comparison to ZMLC (P = .001 to .008). The influence of high-speed sintering on marginal and general fit was not clinically relevant (P = .154 to .877). Conclusion: High-speed sintering influenced the accuracy of 4Y-TZP full-coverage single-unit and three-unit FDPs. However, no clinically relevant impact on fit was observed. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the influence of repetitive autoclaving on diamond burs fabricated via different methods.Materials and Methods: A total of 96 diamond burs were divided into 12 groups according to fabrication method (single-element electroplating, multi-element electroplating, or brazing) and number of times autoclaved (0, 5, 10, or 15). The surface characteristics and components of the diamond burs were examined using scanning electron microscopy (SEM) and x-ray photoelectron spectroscopy (XPS). The cutting efficiency of the diamond burs was tested with a constant-pressure cutting appliance.Results: Compared to the nonautoclaved group, the cutting efficiency of the multi-element and single-element electroplated diamond burs decreased significantly after autoclaving 5, 10, and 15 times (P < .05). The cutting efficiency of the brazed diamond burs started to decrease significantly after 10 cycles (P < .05). Cracks appeared on the surfaces of multi-element electroplated diamond burs after 10 and 15 cycles, but were absent in the single-element electroplated and brazed diamond burs. A reduction of nickel was detected in the multi-element electroplated and brazed diamond burs, but not in the single-element electroplated diamond burs.Conclusion: Repetitive autoclaving could reduce the cutting efficiency of diamond burs. The extent of the reduction was related to fabrication method and number of autoclaving times, suggesting that used diamond burs should be separately autoclaved to avoid shortening the life spans of unused ones. [ABSTRACT FROM AUTHOR]

This study aims to design a stretchable metasurface system that can adaptively change its wettability using additive manufacturing. The system consists of a stretchable specimen with micro-surface patterns and a bi-layer actuator based on compliant mechanisms. Both the specimen and actuator are manufactured using fused filament fabrication additive manufacturing methods. In the proposed system, the actuator stretches the specimen to modify the aspect ratios of the surface patterns. These changes in aspect ratios reduce the air gaps at the liquid/solid interface, which weakens the hydrophobic properties of the specimen surface. To investigate the effect of changes in pattern aspect ratios on surface wettability, experiment is conducted by dropping water droplets onto the specimen while the actuator stretches it. The contact angles of the droplets are measured to quantify the changes in wettability. Additionally, finite element simulations are performed to analyze the specimen strain distribution under various deformation conditions. This allows the evaluation of precise elongation values and prediction of surface wettability, displaying the potential for surface wettability control. These findings support the implementation of additive manufacturing to fabricate a stretchable metasurface system with adaptive wettability. [ABSTRACT FROM AUTHOR]

Functional oxides have extensively been investigated as a promising class of materials in a broad range of innovative applications. Harnessing the novel properties of functional oxides in micro‐ to nano‐scale applications hinges on establishing advanced fabrication and manufacturing techniques able to synthesize these materials in an accurate and reliable manner. Oxidative scanning probe lithography (o‐SPL), an atomic force microscopy (AFM) technique based on anodic oxidation at the water meniscus formed at the tip/substrate contact, not only combines the advantages of both "top‐down" and "bottom‐up" fabrication approaches, but also offers the possibility of fabricating oxide nanomaterials with high patterning accuracy. While the use of self‐assembled monolayers (SAMs) broadened the application of o‐SPL, significant challenges have emerged owing to the relatively limited number of SAM/solid surface combinations that can be employed for o‐SPL, which constrains the ability to control the chemistry and structure of oxides formed by o‐SPL. In this work, a new o‐SPL technique that utilizes room‐temperature ionic liquids (RTILs) as the functionalizing material to mediate the electrochemistry at AFM tip/substrate contacts is reported. The results show that the new IL‐mediated o‐SPL (IL‐o‐SPL) approach allows sub‐100 nm oxide features to be patterned on a model solid surface, namely steel, with an initiation voltage as low as −2 V. Moreover, this approach enables high tunability of both the chemical state and morphology of the patterned iron oxide structures. Owing to the high chemical compatibility of ILs, which derives from the possibility of synthesizing ILs able to adsorb on a wide variety of solid surfaces, IL‐o‐SPL can be extended to other material surfaces and provide the opportunity to accurately tailor the chemistry, morphology, and electronic properties within nanoscale domains, thus opening new pathways to the development of novel micro‐ and nano‐architectures for advanced integrated devices. [ABSTRACT FROM AUTHOR]

The use of additive manufacturing for the fabrication of sacrificial cladding is becoming increasingly popular as it facilitates the production of complex yet space-saving protective structures. Despite this, the effect of several structural parameters on their capacity to mitigate high-velocity impacts remains elusive. Toward this end, the shock-mitigating capacity of various short fiber-reinforced polymer samples was evaluated regarding impact velocity and mass (raging from 1 to 8.3 m/s and 5.5 to 7.5 Kg, respectively). Among the assessed parameters were peak force (measured to vary by up to 46.6%), max. and mean deceleration values (with max. differences documented at 29.5% and 48.2%, respectively) and cushion factor. As expected, the progressive crushing modes differed significantly across the spectrum of the tested samples. Structural failure involved the growth of inter- and intra-laminar cracks, fiber-matrix de-bonding and de-lamination, which was dependent on equivalent pore volume fraction and compressive strength. Increasing infill density led in most cases to higher peak forces during impact, as did the deposition of more solid peripheral layers, with the latter producing a superior deceleration plateau. Evaluated collectively, the results indicate that an infill density of 37% with 4 solid external (protective) layers exhibited the superior impact response among the tested samples. [ABSTRACT FROM AUTHOR]

This paper deals with the evaluation of material properties of the additively manufactured austenistic alloy 08CH18N10T, which is widely used in the Czech Republic nuclear power plants Temelín and Dukovany and other VVER reactors around the world. For purposes of utilization of additive manufacturing technologies for nuclear core components fabrication, two sets of samples were prepared from horizontally and vertically L-DED printed blocks from 08CH18N10T material. Experiments such as microstructure analysis, porosity and Vickers hardness were then performed on L-DED printed and heat-treated 08CH18N10T material, and the obtained material properties were then compared with the properties of L-DED printed 08CH18N10T material without heat-treatment for examination of its effect and also with material properties of conventionally made 08CH18N10T material. [ABSTRACT FROM AUTHOR]

Gas shielded welding is a widely applied fabrication processes in manufacturing industry. The present study will elucidate on an investigative approach to find the mechanical properties, influenced by several input parameters like welding current, voltage and wire spool speed in the Metal Active Gas Welding (MAG) of Mild Steel. Taguchi's L9 orthogonal array has been employed to analyse the process parameters. The levels of consequences of input parameters were investigated by applying analysis of variance (ANOVA). The microstructural orientations and mechanical properties of weld specimen are explored in this work. Welding current is an influential parameter to control tensile strength followed by welding voltage and federate of electrode. Furthermore, hardness of weld material has a greater effect of voltage including wire speed and current. [ABSTRACT FROM AUTHOR]

Disposable face masks are an essential piece of personal protective equipment for workers in medical facilities, laboratories, and the general public to prevent the spread of illnesses and/or contamination. Covid-19 resulted in an uptick in the usage and production of face masks, exacerbating issues related to the waste and recycling of these materials. Traditionally, face masks are derived from petrochemicals, such as melt-blown or spunbound polypropylene. As such, there is a need to find sustainable mask materials that can maintain or improve the performance of petrochemical masks. This paper explores an alternative mask material that utilizes fungal mycelium as self-growing filaments to enhance the efficiency of individual polypropylene mask layers. By engineering the growth pattern and time, breathability and filtration efficiency was optimized such that one layer of the mycelium-modified mask could replace all three layers of the traditional three-layer mask. Additionally, it was found that the mycelium-modified mask exhibits asymmetric hydrophobicity, with super-hydrophobicity at the composite-air interface and lower hydrophobicity at the composite-medium interface. This property can improve the performance of the modified mask by protecting the mask from external liquids without trapping water vapor from the user’s breath. The findings from this study can provide a basis for further development of mycelium to create sustainable filtration materials with enhanced functionality. [ABSTRACT FROM AUTHOR]

Additive Manufacturing (AM) is modernizing the manufacturing industry by enabling the layer-by-layer deposition process to manufacture objects in nearly any form with minimum material waste. However, components developed utilizing the AM process have dimensional constraints. To address this issue, AM-produced metal materials can be coupled with various welding processes. This article focuses on the foundations, highlighting the distinguishing features, capabilities, and challenges of welding-based AM processes by categorizing them into two major groups; arc welding-based AM like Cold Metal Transfer (CMT), Gas Metal Arc Welding (GMAW), Gas Tungsten Arc Welding (GTAW), Plasma Arc Welding (PAW), and high-energy density welding based AM like Laser Beam Welding (LBW) and Electron Beam Welding (EBW). The prior study findings of welding-based AM metal components on mechanical characteristics and microstructural characterization have been addressed. This work will aid researchers, academicians, and professional welders since it gathers vital information on welding-based AM processes. Furthermore, current research in the arena of welding-based AM and its future opportunities has been discussed. [ABSTRACT FROM AUTHOR]

We developed two types of liquid-crystal spatial light modulators: an improved device by modifying each layer of the device and a large active area for industrial infrared lasers to demonstrate innovative manufacturing and fabrication techniques in smart manufacturing. The reconstruction of computer-generated holograms was demonstrated to prove the concept of the proposed device in the IR region. The incident phase performance characteristics of the device under high-power laser irradiation were obtained using a 1030 nm ultrashort pulse laser. [ABSTRACT FROM AUTHOR]

Nowadays removable functional appliances are highly widespread in the field of Orthodontic. The construction bite taking may be challenge trough intraoral scanner. The problem comes from the fact the patient must stay in the exactly same lay, while the operator make right and left digital occlusion. For the patient is easy to make “the same” bite, and the operator make both sides without difficulties. For fabrication of functional appliances the construction bite require to have space between tooth arches, and upper and lower arch to be in determined relations. There is patients, which can stay steel, during the operator make the both sides, but there is always risk to make a little motion, which will compromise the construction bite and fabrication of appliance. Thereby, the operator need “something” which will provide the tooth arches to stay stable during operator take the construct occlusion. Purpose: To evaluate the clinical method for Orthodontic digital construction bite taking. Methodology: Intraoral scanner Medit i 700 was used for presentation of this clinical method. Condensation silicone Zetaplus by Zhermark was used for the bite guide. The patient included in the article was after orthodontic treatment with fixed technique. In the same day the brackets was taken off, the construction bite was taken in clinical setting. Results: The present clinical method was effective to provide stability during construction occlusion for fabrication of Twin Bloc appliance has been taking. The method may be used for any construction bite that is needed – for other functional appliances, for surgical guide and etcetera. Conclusions: The digital intraoral scanner are reliable tool for provide accurate 3D model of the teeth, and to take normal and construction occlusion. The described methodology is a little step in digital workflow process, which provide stability of occlusion and chance for clinician to be sure in construction bite. The advantages that it give are improved patient experience, increased treatment efficiency, time efficiency. This methodology is a little step in digital workflow process, which provide stability of occlusion and chance for clinician to be sure in construction bite. The advantages that it gives are improved patient experience, increased treatment efficiency, time efficiency. The new technology continue to evolve and suite better clinicians needs which affect as improvement of patients care. [ABSTRACT FROM AUTHOR]

This work concerns the design, fabrication, and testing of a novel air-flow sensor employing exclusively additive manufacturing that can be fabricated on-site, aboard a ship, or in a similarly remote area, without relying on external manufacturing facilities. The developed device's principle of operation is based on vortex shedding; its novelty focuses on employing solely additive manufacturing technology, for the manufacturing—in a single process step—of all the sensor's main elements. In more detail, the required flow-shaping housing, the appropriate piezoresistive sensing element, and the electrical interconnection pads are all constructed in a single process step, through standard Fused Deposition Modeling (FDM) 3D technology. Direct communication to the necessary readout circuitry can be easily achieved through standard soldering utilizing the integrated contact pads of the sensor. The prototype was preliminary characterized, validating its proper functionality. Key features of the proposed device are low cost, fast on-site manufacturing of the entire measuring device, robustness, and simplicity, suggesting numerous potential applications in the shipbuilding industry and other industrial sectors. [ABSTRACT FROM AUTHOR]

This work presents a comprehensive investigation into the optimization of critical process parameters associated with metal fused filament fabrication (Metal-FFF) for the production of copper-based components. The study focused on three different commercial and one self-manufactured filament, each with unique chemical compositions. These filaments were systematically optimized and the density was characterized for all processing steps, as well as the electrical conductivity on the specimen scale. Remarkably, two of the studied filaments exhibited exceptional properties after sintering with forming gas (up to 94% density and 55.75 M S / m electrical conductivity), approaching the properties measured for established manufacturing methods like metal injection molding. Finally, the research was extended to component-scale applications, demonstrating the successful fabrication of inductors with integrated cooling channels. These components exhibited water tightness and were used in induction hardening experiments, validating the practical utility of the optimized Metal-FFF process. In summary, the results show great promise in advancing the utilization of Metal-FFF in industrial contexts, particularly in the production of high-performance copper components. [ABSTRACT FROM AUTHOR]

In this paper, we present a systematic approach for the development of application-specific antennas for 5G millimeter-wave (mmWave) base stations. First, an in-depth analysis of 5G mmWave base stations considering the required antenna gain and antenna elements to address different equivalent isotropic radiated power requirements is presented. This is followed by an evaluation of the realistic impact of different factors, which affect mmWave communication, namely output power of power amplifiers, antenna gain, losses and weather condition (rain), on transmission ranges between base station and terminals, considering the link budget analysis for an Urban Macro cell with the Non-Line-of-Sight transmission, as an example. Finally, based on a comparative analysis of published dual-band dual-polarized 5G mmWave antennas, we propose a novel configuration of a dual-band dual-polarized antenna for 5G mmWave base station applications, which overcomes the limitations of conventional antennas in published literature. Our proposed antenna covers the specified 3 GHz bandwidths in the 5G mmWave n257 and n260 bands and reaches approximately 6 and 6.7 dBi, respectively in these bands. Furthermore, it exhibits at least 20 dB isolation between the polarizations and has dimensions of 1.8 3 1.8 3 1.2 mm. We modeled, simulated, fabricated, measured and analyzed this new antenna configuration. Excellent correlation is obtained between measurement and simulation results. [ABSTRACT FROM AUTHOR]

This article describes the assessment of design concepts in order to identify the optimal concept before detail design and fabrications can be carried out. The task of identifying the design features and sub features necessary or required for optimal performance of the design is achievable by virtue of undergoing the concept selection process. In this article, concept selection via fuzzy TOPSIS method is carried out. Various design features and sub features necessary for optimal performance of a pipe bending machine was identified and the fuzzy TOPSIS model was applied to identify the optimal design from a set of alternative designs of the pipe bending machine. The decision process considered the weights of the design features which has a role to play in the final values obtained from the decision. The application to pipe bending machine shows that fuzzy TOPSIS is a practicable tool for assessing design concepts. [ABSTRACT FROM AUTHOR]

Metal-fused filament fabrication (MF3), which is a variation of the conventional fused filament fabrication (FFF), has recently gained interest due to its distinctive process flexibility and rapid prototyping capability to produce metallic parts. With respect to the additive manufacturing (AM) of aluminum alloys, most efforts have been centered on laser powder bed fusion technologies, with limited activities focused on binder-based processes due to challenges in the sintering of aluminum powders. With respect to MF3, one challenge for fabricating metallic components is the appropriate selection of a binder mixture, enabling the extrusion of a filament with high metallic volume content. In this paper, a mixture of biodegradable aliphatic polyester thermoplastic is used as a binder phase to act as the carrier for AlSi10Mg alloy powders. [ABSTRACT FROM AUTHOR]

Screw connection is a type most commonly applied to timber structures. As important commercial tree species in China, Masson pine and Chinese fir have the potential to prepare wood structures. In this study, the effects of the diameter of the self-tapping screw and the guiding bores on the nail holding performance on different sections of Masson pine and Chinese fir dimension lumbers were mainly explored. The results showed that: (1) The nail holding strength of the tangential section was the maximum, followed by that of the radial section, and that of the cross section was the minimum. (2) The nail holding strength of Masson pine was higher than that of Chinese fir. (3) The nail holding strength grew with the increase in the diameter of self-tapping screws, but a large diameter would lead to plastic cracking of the timber, thus further affecting the nail holding strength. Masson pine and Chinese fir reached the maximum nail holding strength when the diameter of self-tapping screws was 3.5 mm. (4) Under a large diameter of screws, prefabricated guiding bores could mitigate timber cracking and improve its nail holding strength. (5) Prefabricated guiding bores were more necessary for the screw connection of Masson pine. The results obtained could provide a scientific basis for the screw connection design of Masson pine and Chinese fir timber structures. [ABSTRACT FROM AUTHOR]