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The consolidation process and morphology evolution in ceramics-based additive manufacturing (AM) are still not well-understood. As a way to better understand the ceramic selective laser sintering (SLS), a dynamic three-dimensional computational model was developed to forecast thermal behavior of hydroxyapatite (HA) bioceramic.

AM has revolutionized automotive, biomedical and aerospace industries, among many others. AM provides design and geometric freedom, rapid product customization and manufacturing flexibility through its layer-by-layer technique. However, a very limited number of materials are printable because of rapid melting and solidification hysteresis. Melting-solidification dynamics in powder bed fusion are usually correlated with welding, often ignoring the intrinsic properties of the laser irradiation; unsurprisingly, the printable materials are mostly the well-known weldable materials.

The consolidation mechanism of HA was identified during its processing in a ceramic SLS device, then the effect of the laser energy density was studied to see how it affects the processing window. Premature sintering and sintering regimes were revealed and elaborated in detail. The full consolidation beyond sintering was also revealed along with its interaction to baseplate.

These findings provide important insight into the consolidation mechanism of HA ceramics, which will be the cornerstone for extending the range of materials in laser powder bed fusion of ceramics.

The low rate of exclusive breastfeeding and the early introduction of complementary feeding are among the causes of nutritional problems in children. The national coverage of exclusive breastfeeding in 2019 was 67.7%, surpassing the target of the 2019 Strategic Plan, which was 50%. However, there are still several practices of early and inappropriate complementary feeding (32.3%) that can be contributing factors to malnutrition problems in children. The purpose of this study was to determine the factors that influence mother’s self-efficacy levels regarding complementary feeding practices among toddlers in the Tengger tribe.

The study conducted was an observational study with a cross-sectional design. It focused on mothers with children aged 6–24 months in Wonokitri village, East Java. Data was collected using a structured questionnaire and information from the local health center. The analysis involved univariate and bivariate analysis using the chi-square test.

Most mothers were aged 20–34 years (78.9%), had a good level of knowledge (61.4%), the last education level of fathers and mothers was high school (47.4%; 54.4%), parents work as farmers (86.0%; 61.4%), Hinduism (98.2%), family income is less than the minimum wage (78.9%), and mothers receive good family support (73.7%). Most toddlers were boys (56.1%), aged 13–24 months (68.4%), and the second child (66.7%). Family support was the only factor that was significantly related to a mother’s self-efficacy in complementary breastfeeding practices (p-value = 0.042).

It is hoped that more families and health workers will support mothers in giving food to their babies based on the guidelines.

This paper collects evidence from indigenous people of the Tengger tribe.

This study aims to investigate the corrosion behavior of stir-cast hybrid aluminum composite reinforced with CeO₂ and graphene nanoplatelets (GNPs) nanoparticulates used as cylinder liner material in the engines (automotive, aerospace and aircraft industries).

The composites were prepared using the stir-casting technique, and their microstructure and corrosion behavior was evaluated using scanning electron microscopy (SEM) and potentiodynamic polarization test, respectively.

The results showed that the addition of CeO₂ and GNPs improved the corrosion resistance of the composites, and the optimal combination of these two nanoparticles was found to be 3 wt.% CeO₂ and 3 wt.% GNPs. The enhanced corrosion resistance was attributed to the formation of a protective layer on the surface of the composite, as well as the effective dispersion and uniform distribution of nanoparticles in the matrix. The 0.031362 was noted as the lowest corrosion rate (mmpy) and was noticed in 94% Al-6061 alloy + (3 Wt.% CeO₂ + 3 Wt.% GNPs) sample at room temperature and at elevated temperatures; the corrosion rate (mmpy) was observed as 0.0601 and 0.0636 at 45 °C and 75 °C, respectively.

In the vast majority of the published research publications, either cerium oxide or graphene nanoplatelets were utilized as a single reinforcement or in conjunction with other types of reinforcement such as alumina, silicon carbide, carbon nano-tubes, tungsten carbide, etc., but on the combination of the CeO₂ and GNPs as reinforcements have very less literatures with 2 wt.% each only. The prepared hybrid aluminum composite (reinforcing 1 wt.% to 3 wt.% in Al-6061 alloy) was considered for replacing the cylinder liner material in the piston-cylinder arrangement of engines.

This study aims to probe the applicability of 2-mercaptobenzothiazole (MBT) functionalized ionic liquids (ILs) as additives in lithium complex grease (LCG) by researching the corrosion inhibiting, rheological and tribological performances.

Electrochemical tests such as electrochemical impedance spectroscopy and potentiodynamic polarization curves were used on Gamry electrochemical workstation to research the corrosion inhibition properties of ILs in 1.0 M HCl corrosive solution. The rheological properties of different grease samples were tested on a rheometer. The tribological properties were investigated on SRV-V oscillating reciprocating friction and wear tester. Scanning electron microscope, X-ray spectrometer and X-ray photoelectron spectrometer were used to characterize the lubricating mechanism.

The 2-MBT functionalized ILs have excellent corrosion inhibition properties. When used as additives in LCG, they both exhibited enhancing effects on thermostability, colloid stability and structural recoverability, and furthermore, outstanding friction-reducing and antiwear properties were also obtained. Surface analysis indicated that the superior lubricating performances of 2-MBT functionalized ILs were mainly ascribed to the formation of tribochemical products on wear tracks, including organic compounds with C–O bond, Fe₂O₃ and FeS₂.

The 2-MBT-based ILs synthesized in this study were multifunctional additives with excellent corrosion inhibiting and tribological properties, which would have a very broad application prospect in lubricating grease industry.

In the past decade, the biopolymeric properties of chitosan (CH) have been largely exploited for various applications. This paper aims to study the use of CH in its nanoform, i.e. as nanofibers blended with polyvinyl alcohol (PVA) for various antimicrobial applications in detail. In particular, their ability toward bacterial growth inhibition, in vitro drug release and their biocompatibility toward tissue growth have been investigated in detail.

Electrospinning technique was adapted for depositing CH/PVA blended nanofilms on the silver foil under optimized conditions of high voltage. Three different concentrations of blended nanofiber samples were prepared and their antimicrobial properties were studied.

The bead diameter and average diameter of blended nanofibers increase with CH concentration. Antibacterial activity increases as CH concentration increases. Increased hydrophilicity in CH-enriched samples contributes to a higher drug release profile.

To the best of the authors’ knowledge, chick chorioallantoic membrane assay analysis has been carried out for the first time for CH/PVA films which shows that CH/PVA blends are biocompatible. CH after being converted as nanoparticles exhibits higher drug release rate by in vitro method.