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3D concrete printing can be used to build many complex structures. However, due to its material properties in the fresh state, it is difficult to construct overhanging structures ...without supports. In order to unleash the true capability of 3D concrete printing, a support structure is required to support any overhanging fresh material, which is usually removed during post-processing. This study demonstrates the feasibility of adjusting the printing parameters to print the main structure and support structure using a single type of building material. It was found that the solidity ratio, which is defined as the ratio between actual and expected filament sizes, was significantly affected by the nozzle travel speed and material volume flow rate. Furthermore, a gap distance characterisation test was carried out to find the maximum distance that the filament can cross over without a significant slump. The results were combined to determine the different printable regions for different operations. An overhang structure was printed to verify the results obtained for the different printing operations. This technique allows complex structure to be built without the need for human intervention throughout the printing process.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A single‐material logical junction with negligible contact resistance is designed by exploiting quantum‐confinement effects in 1T PdS2. The metallic bilayer serves as electrodes for the ...semiconducting channel monolayer, avoiding contact resistance. Heat dissipation is then governed by tunnel loss, which becomes negligible at channel lengths larger than 2.45 nm. This value marks the integration limit for a conventional 2D transistor.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
► A small-strain FFT-based model for elasto-viscoplastic polycrystals is presented. ► Local fields and effective behavior can be computed from a microstructure image. ► Implicit time discretization ...and an augmented Lagrangian iterative scheme are used. ► Benchmarks for mechanical behavior, boundary conditions and convergence are presented. ► The model is used to study the influence of crystal anisotropy on stress hot-spots.
We present the infinitesimal-strain version of a formulation based on fast Fourier transforms (FFT) for the prediction of micromechanical fields in polycrystals deforming in the elasto-viscoplastic (EVP) regime. This EVP extension of the model originally proposed by Moulinec and Suquet to compute the local and effective mechanical behavior of a heterogeneous material directly from an image of its microstructure is based on an implicit time discretization and an augmented Lagrangian iterative procedure. The proposed model is first benchmarked, assessing the corresponding elastic and viscoplastic limits, the correct treatment of hardening, rate-sensitivity and boundary conditions, and the rate of convergence of the numerical method. In terms of applications, the EVP–FFT model is next used to examine how single crystal elastic and plastic directional properties determine the distribution of local fields at different stages of deformation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The growth of implant and fixed prosthodontics practices in dentistry has created a rapidly increasing demand for advanced ceramics and ceramic processes. Innovations in ceramics and ceramic ...processes are vital to ensure reliable and affordable dental-restoration solutions with aesthetically pleasing outcomes. The work aims to engage the bioceramics and engineering communities to meet the challenges of modern dental restoration using advanced ceramics. Incorporating fundamental science, advanced engineering concepts, and clinical outcomes, the work is suitable for bioceramicists, ceramics manufacturers, dental clinicians and biologists. * State-of-the-art-coverage encompasses bioresorbable ceramics for bone regeneration and bioactivating surfaces of inert, high-strength ceramics for implantation, keeping research knowledge appropriately updated * Discusses transition from the baseline stable and physically stiff ceramics research into engineering of highly coherent laminate composites for prosthetic crowns and bridges * Showcases current feasible techniques for producing, in cost-effective and materials-saving ways, long-lasting individualized ceramic components with biocompatibility, complexity and high precision
Functionally graded porous (FGP) nanocomposites are the most promising materials among the manufacturing and materials sector due to their adjustable physical, mechanical, and operational properties ...for distinctive engineering applications for maximized efficiency. Therefore, investigating the underlying physical and materialistic phenomena of such materials is vital. This research was conducted to analyze the preparation, fabrication, applications, and elastic properties of functionally graded materials (FGMs). The research investigated for both porous and nonporous synthesis, preparation, and manufacturing methods for ceramics, metallic, and polymeric nanocomposites in the first section, which is followed by deep research of the development of elastic properties of the above-mentioned materials. Main nano-reinforcing agents used in FGMs to improve elastic properties were found to be graphene platelets, carbon nanotubes, and carbon nanofibers. In addition, research studied the impact of nano-reinforcing agent on the elastic properties of the FGMs. Shape, size, composition, and distribution of nano-reinforcing agents were analyzed and classified. Furthermore, the research concentrated on modeling of FGP nanocomposites. Extensive mathematical, numerical, and computational modeling were analyzed and classified for different engineering analysis types including buckling, thermal, vibrational, thermoelasticity, static, and dynamic bending. Finally, manufacturing and design methods regarding different materials were summarized. The most common results found in this study are that the addition of reinforcement units to any type of porous and nonporous nanocomposites significantly increases materialistic and material properties. To extend, compressive and tensile stresses, buckling, vibrational, elastic, acoustical, energy absorption, and stress distribution endurance are considerably enhanced when reinforcing is applied to porous and nonporous nanocomposite assemblies. Ultimately, the review concluded that the parameters such as shape, size, composition, and distribution of the reinforcing units are vital in terms of determining the final mechanical and materialistic properties of nanocomposites.
The influence of Mn substitution on the iron lattice sites in LiFeO
2
material was investigated with respect to the electronic, crystalline, and electrochemical properties of the material, using the ...LiFe
1−
x
Mn
x
O
2
(
x
= 0.0, 0.05, and 0.10) series. The electronic structure study was conducted with the acquisition of x-ray absorption fine structure spectroscopy data, while the crystal structure properties of the studied materials were investigated using x-ray diffraction patterns. The data collected for the ionic conductivity properties of the samples by electrochemical impedance spectroscopy under increasing temperature conditions around and above room temperature aided the crystal and electronic structure studies on cathode materials. Furthermore, studies were conducted with the addition of CrFe
2
O
4
material in varying molar concentrations into LiFeO
2
material, as CrFe
2
O
4
is known to have thermoelectric properties well above the room temperature of 400 K (127°C). Encouraging results for next-generation battery cathodes were obtained.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The cuticle exoskeleton plays a key role in facilitating the evolutionary success of insects. Since the mid of the last century, many different biomechanical properties of exoskeletons have been ...investigated, always utilizing the most sophisticated scientific methods available at the time. So far, information on the biomechanical properties of cuticle seems to be as diverse as the methods used to measure them. As a consequence, insect cuticle is often considered to exhibit the most complex and diverse biomechanical properties of any biological material. However, it remains unclear which role the respective measurement methods and sample treatments used in previous studies play in supporting this claim. This review provides a broad overview of examination techniques used to study biomechanical properties of insect exoskeletons and discusses their respective advantages and disadvantages in describing the properties of a complex material such as cuticle. Our meta-analysis of the present data confirms significant effects of the respective measurement methods, sample treatments and body parts on the obtained mechanical properties. Based on our findings, we highlight research gaps and point out important factors which should be taken into account in future studies on insect cuticle.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
•Gypsum boards added with porous materials and phase change materials were prepared.•Hygrothermal performance of specimens was analyzed based on ISO 12,571 and 12,572.•Thermal conductivity of ...specimens was lower than conventional gypsum board.•Water vapor resistance factor was higher than gypsum board after impregnation of PCM.•There were no moisture problems of gypsum boards with porous materials and PCM.
Gypsum board is widely used as a finishing material, and it is mixed with functional materials to improve the comfort level of indoor air, provide thermal insulation, and satisfy moisture properties. In addition, Phase change material (PCM) is also used as a functional material to reduce energy consumption. Recently, there have been many studies on improving moisture problems, such as condensation and mold growth. Therefore, the hygrothermal behavior of building materials must be carefully considered to reduce the risk of moisture problems. The objective of this study was to improve the thermal and moisture performance of gypsum board, and achieve energy savings by adding porous material and PCM. The characteristics of functional gypsum board (FGB) with expanded vermiculite (EV), expanded perlite (EP), nano carbon material (C300), and n-octadecane (PCM) were analyzed by fourier transform infrared (FTIR) spectroscopy for structural stability. The thermal conductivities of the various FGBs were analyzed by TCi thermal conductivity analyzer, and their hygroscopic properties were analyzed based on ISO 12,571 and 12,572. In addition, the hygrothermal performance of walls applied with FGB was evaluated using Wäme und Feuchte instationär (WUFI) simulation; the wall composition was concrete wall. As a result, the thermal conductivities of FGB were decreased by 15%, compared with the conventional gypsum board. In the case of moisture properties, the water vapor resistance and water content of FGB were increased, compared with the conventional gypsum board (SR). However, the simulation results showed that there were no moisture problems, such as condensation, mold growth, or structural damage.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
2D materials are promising to overcome the scaling limit of Si field‐effect transistors (FETs). However, the insulator/2D channel interface severely degrades the performance of 2D FETs, and the ...origin of the degradation remains largely unexplored. Here, the full energy spectra of the interface state densities (Dit) are presented for both n‐ and p‐ MoS2 FETs, based on the comprehensive and systematic studies, i.e., full rage of channel thickness and various gate stack structures with h‐BN as well as high‐k oxides. For n‐MoS2, Dit around the mid‐gap is drastically reduced to 5 × 1011 cm−2 eV−1 for the heterostructure FET with h‐BN from 5 × 1012 cm−2 eV−1 for the high‐k top‐gate. On the other hand, Dit remains high, ≈1013 cm−2 eV−1, even for the heterostructure FET for p‐MoS2. The systematic study elucidates that the strain induced externally through the substrate surface roughness and high‐k deposition process is the origin for the interface degradation on conduction band side, while sulfur‐vacancy‐induced defect states dominate the interface degradation on valance band side. The present understanding of the interface properties provides the key to further improving the performance of 2D FETs.
The interfacial properties of both n‐ and p‐MoS2 field‐effect transistors with a wide thickness range and various gate stack structures are investigated. The full energy spectra of the interface state densities are extracted. The external strain dominates the interface at the conduction band side, while sulfur‐vacancy‐induced defect‐states dominate the valance band side.
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This comprehensive book provides up-to-date information on the developments in the field of biopolymers. Close attention has been paid to include all the important aspects that are necessary to ...understand the field. The book introduces the reader with the progress in the field, followed by outlining its applications in different areas. Different methods and techniques of synthesis and characterisation are detailed as individual chapters. Various mode and mechanism of degradation of materials will be discussed. There is a dedicated chapter on industrially available biopolymers and their applications and well as a chapter detailing the ongoing research, current trends and future challenges. Unlike other books, this book consists of information that is useful for students who are interested in biotech and polymer research. Each chapter will explain the science and techlogy from the inception to advance state of the art available to date. This book will also be useful for the researcher involved in high-tech research as it will provide up-to-date information available in this field.
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