Current Materials Science - Volume 18, Issue 3, 2025

Criminal actions using falsified papers are on the rise. Any changes to the document's content are usually made with ballpoint and gel pens. All changes made to a document using a pen necessitate ink analysis. Thus, a quick and accurate ink analysis process must be created to cope with the challenges associated with counterfeiting.

This study aims to analyze several brands of ballpoint and gel pen inks using physicochemical and computational techniques and provide a database of the results.

A total of 24 pen samples from various brands were colour-tested first, followed by an optical test using ImageJ software. The composition of each ink sample was distinguished using the non-destructive method ATR-FTIR, followed by a destructive technique TLC. Lastly, a computational technique algorithm was applied for rapid and desirable results.

The results distinguished each brand based on RGB measures and mean values. The differentiation of each sample using ATR-FTIR spectroscopy was challenging due to similar structural characteristics. However, TLC (destructive) was used with several solvent systems. Ballpoint pen inks separated well in all solvent systems, with the greatest results achieved in solvent systems 2 and solvent system 4. The TLC spots were identical, but when evaluated digitally using MATLAB, substantial changes were visible, which were utilized to differentiate similar colour inks from various brands.

The chemical approaches, in conjunction with the computational techniques, offered a rapid and sophisticated method that allowed for better distinction of the inks and provided more accuracy in substantially less time than typical methods employed in forensic laboratories.

Augmenting concern towards effective utilization of agro waste into useful products has formented the scientific community to look for alternate sources of materials. On a circular economy contemplation, natural fibers extricated from agro waste have a potential headway towards the evolution of newer materials.

The current research activity is focused on the optimization of influential parameters, namely fiber volume, load, sliding distance and sliding velocity on the wear characteristics of inflorescence fiber-fortified epoxy composites. Coconut Inflorescence fiber is selected as reinforcement material for the present work. NaOH treatment at 5% wt/vol for 1 hour towards removal of amorphous contents present in the fibers. Taguchi-inspired L16 orthogonal array is used for the design of experiments using Minitab software. The control factors chosen for the optimization study are namely fiber content (10 mm, 15 mm, 20 mm and 25 mm), a load of (5 N, 10N, 15 N and 20 N), a sliding distance of (200 m, 400 m, 600 m and 800 m) and sliding velocity of (6 m/s, 12 m/s, 18 m/s and 24 m/s).

The optimal combination of parameters, namely fiber content of 20 wt%, load of 5N, a sliding distance of 600 m and sliding velocity of 24 m/s, contributed to the merest wear rate of 4.328 m³/N.m. Morphological evaluation of the composites revealed agglomeration of fibers in the matrix, thereby, the matrix was not able to transfer load uniformly.

Leading to failure of composites as a result of wear rate increase. Thus, inflorescence fiber-fortified epoxy composites fabricated on the above-mentioned control factors will have better wear rate for futuristic applications.

Sustainable synthesis of γ-valerolactone (GVL) from levulinic acid (LA) offers a sustainable approach to converting biomass-derived feedstocks into valuable chemicals and fuel additves. Cu-Hydroxyapatite (Cu-HAp) catalysts are potential candidates for vapor-phase hydrogenation of LA to GVL due to their enhanced catalytic activity and selectivity through Cu nanoparticle support.

This study aimed to investigate the catalytic performance of Cu-HAp catalysts in the hydrogenation of levulinic acid to γ-valerolactone. The primary goal was to optimize reaction conditions and assess the enhanced catalytic activity and selectivity.

The influence of copper loading, reaction temperature, and catalyst stability was evaluated. Moreover, the effect of time on stream (TOS) on LA conversion and GVL selectivity was examined by the best optimised Cu/HAp catalyst.

Cu-HAp catalysts exhibited favorable catalytic performance, with optimal conditions at approximately 5 wt% copper loading. At this loading, maximum LA conversion (60%) and GVL selectivity (90%) were achieved after 8 hours on the stream at 265°C and 0.1 MPa conditions.

The study demonstrates the efficacy of Cu-HAp catalysts for the hydrogenation of levulinic acid to γ-valerolactone. The findings indicate that as the copper loading increases from 2 to 20 wt%, the conversion of LA and the selectivity to GVL both decline. The analysis further implies that the dispersion of Cu species corresponds directly to the activity observed during the LA hydrogenation. The conversion of LA rises with a higher reaction temperature ranging from 250-320°C, although the selectivity of GVL decreases above 265°C. The catalyst's stability is crucial for maintaining efficient catalytic activity over time, with observed deactivation attributed to Cu metal particle aggregation and coke formation on active sites. The findings contribute to the development of robust catalyst systems for biomass-derived chemical transformations.

Carbon is widely recognized as a unique element because of its versatile nature resulting in its variety of applications. The adsorption process is among the most effective techniques for the removal of many transition metal ions from adsorbent Kavat Shell carbon (KSC).

Activated charcoal is synthesized by a chemical activation technique using KOH as an activating agent. The objective of this research is to study the elimination of transition metal ion and their adsorption is discussed under various optimum experimental conditions. Langmuir, Freundlich, and Temkin adsorption isotherms fitted to the data well.

The important scope of this research is to prepare microporous activated carbon from Limonia Acidissima by chemical activation and to investigate the concentration of metal ions.

Similarly, the surface morphological study was also examined via Scanning Electron Microscopy (SEM), and functional groups were analyzed using energy dispersive X-ray diffraction spectroscopy (XRD) and Fourier Transform Infrared spectroscopy technique (FTIR), respectively.

A key concern in tissue engineering for bone regeneration is the fabrication of scaffolding so that it serves as a template for cell interactions and the formation of bone’s extracellular matrix to provide structural support to the newly formed tissue.

In the current study, different amounts of citric acid from 65 to 85 (vol%), including different particle sizes (between 250-700 μm), were used as a porogen to fabricate porous biphasic calcium phosphate scaffolds.

The scaffolds were prepared under different pressures of 150-250 MPa followed by sintering at various temperatures of 1100-1300°C. The compressive strength, total porosity, volume shrinkage, phase composition, and microstructure of the samples were evaluated.

Scaffolds with a macropore size of 100-500 µm were produced by citric acid porogen. The compressive strength varied using different ranges of porogen particle size (containing the same porogen content) as well as concentration. The results showed that the compressive strength decreased when the applied pressure increased from 150 to 250 MPa and a higher amount of porogen was used. The maximum value of compressive strength was ~13.9MPa, for the sample sintered at 1200°C and had a total porosity of ~55.3%.

This kind of porous biphasic calcium phosphate can exhibit an appropriate ability to be used as a bone substitute due to its physico-mechanical outcomes and approved bioactive structure.