Advanced Materials Research Vol. 1186

Abstract: Radiation is essential in medical diagnostics but poses health risks, necessitating effective shielding to minimize exposure. This research evaluates cassava starch-based bioplastic-lead as an alternative radiation shielding material in femur radiography using Anteroposterior (AP) and Lateral projections with portrait and diagonal detector positions. Bioplastic samples with a 45:55 ratio of cassava starch and lead acetate were tested on a preserved human femur with and without shielding. Image processing using the Gaussian High Pass Filter (GHPF) method and analysis with Contrast to Noise Ratio (CNR) and Peak Signal to Noise Ratio (PSNR) were conducted to assess image quality. Results showed that lead bioplastics achieved 49.4% radiation absorption, with optimal anatomical visualization at cut-off frequencies of 5 and 10, while higher frequencies led to image distortions resembling osteoporosis. The best CNR and PSNR values confirmed improved image contrast while maintaining diagnostic accuracy. This research demonstrates that lead bioplastic effectively reduces radiation dose while preserving image quality, making it a promising alternative shielding material for medical imaging applications

Abstract: Hydroxymethylfurfural (HMF), a by-product in the dilute acid hydrolysis of biomass, and is commonly seen as fermentation inhibitor in bio-ethanol production. However, HMF is also considered an important chemical in the synthesis of various bio-based products, particularly bioplastics. This study investigated the production of HMF from sugar-rich brewers’ spent grains (BSG) hydrolysates. BSG (15 %wt./wt. solution) was subjected to dilute acid hydrolysis (5% v/v sulfuric acid ) for 30 minutes at 121°C to produce a sugar-rich hydrolysate (SRH) having a reducing sugar content of 33.97 ± 1.21 %wt. glucose equivalent. The SRH was subjected to a dehydration reaction and the effects of aluminum chloride catalyst loading (ACL) (5, 10, and 15 %w/v) and reaction temperature (120, 130, and 140 °C) on the HMF content of the hydrolysate were investigated in this study. Results show that a higher ACL (15 %w/v) and reaction temperature (140 °C) lead to higher HMF content (144.7 ± 9.9 ppm). Additionally, both reaction temperature and ACL, together with its interactions terms, were found to significantly affect HMF content, with temperature having a more significant effect than ACL. A simplified kinetic model was developed to gain further insight into the dehydration reaction at chosen process conditions (ACL = 15 %w/v; T= 140 °C) which produced maximum HMF content. Results show that the proposed kinetic model on reducing sugar dehydration agrees with the experimental data with a good model fit. Moreover, results suggest that HMF, furfural, and humins actively compete in their formation from reducing sugar dehydration, with HMF being less favorable in its production at the employed reaction conditions.

Abstract: This research focuses on bibliometric analysis using R Studio and Bibliometrics as tools for data collection and evaluation related to advances and trends in developing organic-based composite materials with polymeric matrices. The importance of this analysis lies in understanding how these materials require a well-defined matrix that acts as a continuous phase, providing resistance to compressive stress while facilitating interaction with the discontinuous phase to withstand tensile forces. Additionally, it is essential to objectively establish the reinforcing fibers that make up the dispersed phase, as they protect the material against environmental factors and mechanical agents, preventing negative effects such as wear, buckling, and compressive stress. Proper selecting phases is crucial when evaluating the results obtained about the estimated values. Thus, one of the main challenges in formulating polymeric compositions for composite material development is the accurate identification of matrices along with the supporting material. As a result of the challenges associated with the production of these materials, this research confirms, through bibliographic analysis, the increasing exploration of such composites, their impact on various fields throughout history, the technical difficulties inherent in their fabrication in many proposed cases, and the costs involved in their manufacturing.

Abstract: Growing concerns on environmental deterioration is driving the research towards the use of renewable resources in the production of various materials. Biomass feedstocks, such as agricultural and food industry residues, present many advantages as these are widely available, can be inexpensive resources for commercial biorefineries, and can help in the waste reduction in most industries. In the Philippines, ample mango waste is generated due to its flourishing mango processing industry. Mango wastes have already shown valorization potential in numerous studies, however, studies on mango seed husk (MSH) are still limited. This study characterized the lignin found in MSH derived from kraft pulping as phenol substitute in the phenol-formaldehyde (PF) resin synthesis. During kraft delignification, the effects of alkali charge (7.3-20.7% Na₂O), temperature (130-180°C), and liquid-to-solid ratio (LSR) (6.59-23.41 w/w) on the lignin yield were examined using central composite design. The model obtained showed that lignin yield is influenced by the process variables in the following order of decreasing significance: alkali charge, LSR, and temperature. Moreover, low R² values are observed suggesting that there may be other factors affecting the response not considered in this study and that the model has low predictive power. In addition, MSH lignin was isolated from the black liquor by single-step acid precipitation at pH 2 with 20 wt% H₂SO₄. Characterization using FT-IR and difference UV spectroscopy showed that kraft MSH lignin could be a great potential as phenol substitute in PF resin production as it is mostly represented by guaiacyl units and has high total phenolic hydroxyl groups content (3.38 mmol/g). MSH lignin, with its high phenolic hydroxyl content and guaiacyl structure, has diverse industrial applications beyond resin synthesis. It can be used as a natural antioxidant in polymers, a bio-based adhesive for wood products, a UV-absorbing agent in coatings, a precursor for carbon fibers, and a surfactant in concrete and agricultural formulations. Additionally, its antimicrobial properties make it suitable for pharmaceuticals and cosmetics.

Abstract: Essential oils contain volatile compounds that degrade easily when exposed to oxygen, light, moisture, or heat. The selection of packaging materials as a barrier to the loss of volatile compounds in food is something that needs to be considered. This study evaluates the effectiveness of the tea bag material types made of Nylon, PLA (Polylactid Acid), and NWP (Natural Wood Pulp) during a 30-day storage period on the controlled release of volatile compound components in black cinnamal and green cinnamal tea bags products. Analysis of the concentration of volatile compounds during the storage period was carried out using GC (gas chromatography) and GC-MS (gas chromatography-mass spectrometry). The results showed that in black cinnamal tea, the ability to controlled release volatile compounds in PLA (polylactic acid) packaging tends to be better than other packaging. PLA maintaining higher and more consistent concentrations of E-citral and cinnamaldehyde during storage because the pore size of PLA is three times smaller than nylon, so that black cinnamal tea powder remains in the tea bag during storage. In addition, the pore size tea bags also affects permeability, where the permeability of PLA is higher than NWP, so that tea components in PLA bags are better brewed than other bags. In green cinnamal tea, NWP (natural wood pulp) packaging showed a more effective and controlled release of E-citral and cinnamaldehyde, maintaining stable and high concentrations during a 30-day storage period, this can occur because the pores of NWP are smaller than PLA and nylon packaging, which makes green cinnamal tea especially cinnamon powder which is separated from the tea powder grains due to inhomogeneity during mixing remain in the tea bag during storage. In contrast, packaging materials and storage time did not significantly affect the controlled release of Z-citral in either black or green cinnamal tea, indicating low volatility or high stability of this compound.

Abstract: This study investigates the functional groups of 3D printing material filaments made from biocomposites using polymers and natural fibers, analyzed through FTIR spectroscopy. The process of making 3D printing filament uses the extrusion method with a single extrusion machine. The integration of natural fibers into polymer matrices provides a sustainable alternative for 3D printing materials, improving mechanical properties while reducing environmental impact. FTIR analysis revealed significant interactions between polymer and fiber components, identifying key functional groups such as hydroxyl and carbonyl that are critical for performance. Functional groups such as hydroxyl (-OH) and carbonyl (C=O) significantly influence the quality of biocomposites through their impact on the material's mechanical, thermal, and interfacial properties. These findings provide insight into the structure-property relationship of these materials, demonstrating their potential for sustainable 3D printing applications.

Abstract: Azolla pinnata extract and iron chloride were combined under optimized conditions using Response Surface Methodology (RSM) to synthesize Azolla pinnata-iron oxide nanoparticles (AP-IONPs). The study investigated the effects of three key parameters mixing ratio of iron chloride to Azolla pinnata extract (v/v), solution pH, and mixing temperature on the removal efficiency of nickel (Ni²⁺) ions from aqueous solutions. A Central Composite Design (CCD) was employed to develop two-factor interaction (2FI) and quadratic models describing the influence of these variables on nanoparticle synthesis and adsorption performance. Analysis of Variance (ANOVA) was used to determine the most significant factors affecting Ni removal. The optimal synthesis conditions were identified as a mixing ratio of 2.5:1, solution pH of 2.5, and a temperature of 70 °C. Under these conditions, the predicted and experimental Ni removal efficiencies were 98.1% and 97.1%, respectively, with a prediction error of just 1.02%. Keywords: Green synthesis; Response surface methodology; Azolla pinnata; Nanoparticles Heavy metals; Nickel; Adsorption.

Abstract: This study examines the physical properties and oil sorption behavior of fibers extracted from the spikelets of Oil Palm Empty Fruit Bunch (OPEFB). The research begins with preparing spikelet fibers from OPEFB, followed by physical characterization testing, specifically surface morphology analysis, and concludes with oil absorption testing in Palm Oil Mill Effluent (POME). The findings reveal that spikelet fibers possess significant physical properties conducive to oil and grease adsorption, as evidenced by Scanning Electron Microscopy (SEM) and contact angle value. The adsorption efficiency achieved by spikelet fibers in removing oils and greases from POME reached an impressive 99%. The flow rate of the influent has a crucial role in determining the adsorption efficiency, with lower flow rates generally yielding higher efficiencies due to prolonged contact times. Notably, the use of spikelet fibers increased Soluble Chemical Oxygen Demand (SCOD) concentration to 2855 mg/L. This increment in SCOD can be attributed to the degradation of complex organic matter present in the empty fruit bunches. Overall, this research highlights the dual role of spikelet fibers in oil adsorption and the subsequent impact on water quality, suggesting the need for further investigation into their application in wastewater treatment.

Abstract: The issue of waste generation is becoming increasingly pressing in numerous nations worldwide, especially in urban regions experiencing rapid population increase and industrialization. Diseases can spread, land can become degraded, and air and water pollution can all be caused by improper garbage disposal. Additionally, the production of waste uses a lot of energy and natural resources, which depletes vital resources and increases emissions of greenhouse gases. To mitigate these concerns, sustainable waste management strategies that reduce trash generation and promote source reuse and recycling are needed. Among these is the development of novel technologies for environmental bioremediation and protection, building materials, and the application is Microbial Induced Calcite Precipitation (MICP). This is an efficient way to turn waste into useful and long-lasting applications. Utilizing bacteria and chemical reagents in conjunction with biotic processes to generate mineral bicarbonate, MICP is an eco-friendly method. The material has the potential to be a sustainable, economical, and energy-efficient solution to technical and environmental problems. Recent research has shown that waste may be used in place of several MICP chemical modules that are present in the cementation reagents (urea and calcium source) and the medium used to cultivate microorganisms. Additionally, it has been established that the MICP is a sustainable and economically viable technology that works with a variety of waste media. With a focus on the role of recyclable waste, this in-depth review study attempts to give a full grasp of the engineering applications and environmental benefits of MICP technology. It also provides academic indications on how to recognize and address possible complexities when using recyclable waste sources for the use of the MICP technique.