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•Layer height, print speed, and nozzle diameter affect the printability of rice protein.•A large nozzle diameter (2.2 mm) was the least recommended for rice protein printing.•A nozzle ...diameter of 1.7 mm and a speed of 35 mm/s reduced over-extrusion effects.•Process parameters affect the storage module of food inks.
The combination of printing parameters appropriately improves the printability of 3D-printed foods. In this regard, the present study aims to evaluate the effect of 3D printing process parameters on protein food generation. Printability of a cylinder 3 cm in diameter and 1 cm in height using a protein mixture of rice water and xanthan gum with a ratio of 30:70:0.5 was evaluated in an extrusion printer with an XYZ system. A ½ fractional factorial design was used with three factors: nozzle diameter (1.2 – 2.2 mm), layer height (1.0 – 2.0 mm), and print speed (20 – 50 mm/s). Each combination of factor levels was performed in triplicate for 12 runs plus three central points. Print time (min), sample weight, change in diameter (%), change in height (%), change in volume (%), mass flow rate (mg/s), appreciation (qualitative variable), and textural and rheology characters were obtained as response variables. The linear effects of the factors and combination factors were evaluated by analysis of variance. Additionally, a principal component analysis was performed to visualize the similarity between the observations and the relationship between the variables. The results showed that the layer height and nozzle diameter affect the printing accuracy concerning surface quality, shape stability, resolution, and layer layout. The nozzle with a diameter of 1.7 mm combined with speeds between 35 and 50 mm/s allowed the effects of overextrusion to be overcome, generating a better flow of the material. Low scores in the printability variable were related to low-speed values (20 mm/s) and a high nozzle diameter (2.2 mm), which generated higher deformations in the printed protein cylinder. Additionally, some printing conditions affected the textural and rheological characteristics, which allowed inferring that the capacity of the protein mass to store and recover energy in compression processes is conditioned by the printing parameters.
Printing in 3D in academic libraries has been implemented for over a decade, yet unfortunately, many academic libraries around the world, especially in developing countries, still do not see the need ...for 3D printers. The purpose of this article is to present a methodology for selecting the most appropriate kind of 3D printers for use in academic libraries. In order to achieve this objective, a review of the literature was undertaken to arrive at a set of criteria for the selection of these 3D printers. During the development of the article, the author used his own experience of working with 3D printing technologies in academic activities. Among the most crucial criteria for the selection of 3D printers are: functionality; usability; realization/interface; availability/distribution method; user manual; licensing practice; documentation; ease of personalization; ease of implementation; price/cost; reliability; opportunities; market penetration; community/support; device manufacturer; error/problem list; target; cross-platform; interoperability; modularity; DIY; safety; environmental awareness; usage/working range; practical application in a given library. The collected data can be of value to academic libraries facing the dilemma of trying to decide if they should implement 3DP and, if so, what criteria to follow for the selection of 3D printers.
Here, we report a novel 3D printed layered ordered mesoporous template that can encapsulate active Co-MOFs species in a confined way to achieve the goal of monolithic catalyst. The monolithic ...OM-Co3O4@SiO2–S catalyst can maintain a macroscopic porous layered structure and a microscopic ordered mesoporous structure. This monolithic OM-Co3O4@SiO2–S catalyst has excellent catalytic performance (T 90 = 236 °C), water resistance, and thermal stability in the catalytic combustion of toluene. The catalytic performance of the monolithic OM-Co3O4@SiO2–S catalyst is much better than that of many monolithic catalysts reported in the former. Among them, the introduction of binder aluminum phosphate (AP) can effectively enhance the rheological properties of the printing ink, achieve the purpose of ink writing monolithic layered porous material, enrich the acidic point of the monolithic catalyst, and increase the number of reactive oxygen species. This work reveals a novel monolithic catalyst forming strategy that can combine the advantages of ordered mesoporous materials with active species to form macro-layered porous materials and provide ideas and an experimental basis for the elimination of VOCs in industrial applications.
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•3D printed bionic palisade cell improves the photocatalytic efficiency by adjusting the photon and mass transfer of macro structure.•The interface electric field of p-n ...heterojunction inhibit the recombination of photogenerated carrier.•COOH* is important intermediates in photocatalytic CO2 reduction.
Use of 3D photocatalytic reactor has been widely explored for development of efficient photocatalytic systems. In the present study, a bionic palisade cells BiOBr/Sr2Nb2O7/Al6Si2O13 photocatalytic reactor with high strength was prepared through combination of 3D printing technology and solvothermal method. The carefully designed and optimized bionic palisade cell structure exhibited a periodic porous structure with high surface area. The controllable periodic structure effectively regulated the internal photon transfer and mass transfer. Photon transfer ensured that light is fully scattered within the structure, which improved light utilization. High mass transfer ensured smooth flow of reactant inside the structure, which increased reactant adsorption on the surface of photocatalysts. The interface electric field of the BiOBr/Sr2Nb2O7 p-n heterojunction effectively separated the photogenerated electrons and holes. The BOB/SNO/ASO structure had high photocatalytic CO2 reduction performance under the simulated sunlight. The CO yield for the reaction was 13.68 μmol/g/h, whereas that of CH4 yield was 6.37 μmol/g/h. Therefore, the findings of the present study provide a basis for design and preparation of high-performance 3D photocatalytic reactors.
•Blast experiments were conducted to study the close-in blast effect and failure characteristics of honeycomb HSPs.•The blast performance of auxetic HSPs is compared with regular hexagonal ...HSPs.•Simulation is in good agreement with experiments and can describe the deformation and fracture damage.•The effect of the core type and unit-cell angle on the damage of HSPs is investigated.
3D-printed auxetic honeycomb sandwich panels (HSPs) have considerable potential for blast resistance enhancement. This study aims to bridge the gap with regard to the experimental data on the effect of 3D-printed auxetic hexagonal honeycomb cores on the blast response of HSPs. To this end, the blast resistance of HSPs developed using auxetic re-entrant and regular hexagonal honeycomb cores is investigated experimentally and numerically. First, six HSPs are tested under close-in blast loadings. The HSPs comprise Q345 steel top and bottom sheets as well as a honeycomb aluminum alloy core with two configurations (regular hexagonal and auxetic re-entrant). According to the results, the former configuration enhances the HSP blast resistance by not only decreasing the deformation of the HSPs but also improving their damage tolerance. In addition, the responses of the HSPs are numerically studied via finite element analysis. The numerical method using the finite element program LS-DYNA achieves reasonable accuracy. Finally, a parametric study is conducted to investigate the effects of the honeycomb type, cell angle, debonding effects, and core material on the blast resistance of the HSPs. The results demonstrate that employing auxetic hexagonal honeycomb core, smaller cell angle, and ductile core material can improve the blast resistance of HSPs.
Abstract Objective Patient-based congenital heart surgery (CHS) training is opportunity-based and difficult. Three-dimensional (3D) print models of the heart were used for hands-on surgical training ...(HOST) at the 2015 AATS and subsequently in 2 local institutions. We aim to introduce the process of 3D printing for surgical simulation and to present the attendee's responses. Methods Using CT or MR angiograms, the models of congenital heart disease were created and printed with flexible rubberlike material. Altogether, 81 established surgeons or trainees performed simulated surgical procedures with the expert surgeons' guidance and supervision. At the completion of the session, 50 of 81 attendees participated in the questionnaire assessment of the program. Results All responders found the course helpful in improving their surgical skills. All would consider including HOST sessions in the training programs. All found that the models showed the necessary pathologic findings. Most found that the consistency and elasticity of the model material were different from those of the human myocardium. However, the responders thought that the quality of the models was acceptable (88%) or manageable (12%) for surgical practice. The major weaknesses listed were related to the print material and poor representation of the cardiac valves. Conclusions HOST using 3D print heart models is achievable and allows surgical practice on pathological hearts without patients' risk. HOST is a highly applicable surgical simulation format for CHS. Incorporation of HOST in training programs could change the traditional opportunity-based education to the requirement-based standardized education.
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•3D-printed tilt sensors are easy to manufacture, light, compact and cost effective.•Biaxial measurements provide larger operating range of the tilt sensor.•Fiber Bragg gratings ...approach were used due to its immunity against electromagnetic interference and short circuits.•A fiber Bragg grating is added as a temperature sensor to compensate the shift due to the change in temperature.
In this work, a novel 3D-printed biaxial sensor system for tilt measurement, based primarily on the use of four Fiber Bragg Grating (FBG) devices, has been developed and its performance characterized. The tilt sensor system created is of a compact design and relatively small dimensions, making it ideally suited to a variety of industrial applications. In the system developed, the four FBGs used were spliced in a serial formation and attached to four different sides of the sensor structure designed, to allow biaxial measurements to be made. The wavelengths' shift of the FBGs used were monitored as a function of the tilt of the device, using an Optical Spectrum Analyzer (OSA) for this development work. In the sensor, an average FBG-based responsivity of 0.01 nm/° of tilt was measured for each of the different FBGs used. To provide compensation for temperature changes in the system itself, a further FBG-based approach was used (in which they were configured to be insensitive to the effect of the tilt). They were thus calibrated by being exposed to a range of operational temperatures for the system, showing, as a result, a calibration of 0.011 nm/°C. Prior work on the sensor system had proved it to be highly linear in response, over the tilt range of 0° ± 90°. The experimental results obtained from the performance characterization indicate that the small, compact design of this type yields excellent responsivity, compared to other larger and more complex designs discussed in the literature. The sensor system was also relatively easy to fabricate using the 3D-printing method, creating in that way an inexpensive, temperature-compensated tilt monitoring device that had a wide variety of potential industrial applications.
The rapid advancement of additive manufacturing (AM), including Fused Deposition Modeling (FDM) technology, hinges significantly upon the continuous evolution of AM materials. To enhance the ...mechanical characteristics of these materials, filling of carbon or glass fibers has added to them. Consequently, this research delved into the analysis of a carbon fiber-filled polyamide composite. The primary objective was to investigate the impact of printing orientation and pre-printing material drying on the tensile and flexural mechanical properties. Tensile properties were analysed in accordance with ISO 527 standards, while ISO 178 standards were employed for the evaluation of flexural properties. The findings from this study showing the influence of printing orientation and pre-printing drying on both tensile and flexural properties, thereby contributing valuable insights to the field of AM materials development. Keywords: PA-CF; Composite; 3D Print; FDM; Printed Material.
Natural tissues possess the self-strengthening ability through biological growth, during which additional building blocks are transported into the tissues and attached to the pre-existing ...microstructures. In contrast, synthetic materials are typically static, meaning neither their dimensions nor their mechanical properties are able to be altered after the materials are manufactured into specific structures. Recently the concept of bio-inspired synthetic material arises, aiming at developing materials with dynamically programmable performances. Based on the idea of multinetwork (MN) elastomer, we propose a solvent-free elastomer composite system that can be strengthened through tunable self-growth cycles. Resembling biological tissues, chemical structures of the composite remain constant after self-growing, while its dimension, modulus, strength and swelling ability can be programmed on demand. The elastomer composite is naturally compatible with Digital Light Processing (DLP) 3D printing, which directly enables the fast manufacturing of high-precision structures. Applications of the self-growing composites in metamaterials with tunable mechanical performance and waterproof structures are exhibited at the same time.
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