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This study aims to characterize the properties of natural cellulose fiber from the pseudo-stems of the curcuma zedoaria plant.

The fiber was extracted using the biological retting process (cold-water retting). The intrinsic fiber properties obtained were used to evaluate the possibility of using fiber for textile applications.

The average length of a curcuma zedoaria fiber was 34.77 cm with a fineness value of 6.72 Tex. A bundle of curcuma zedoaria fibers was comprised of many elementary fibers. Curcuma zedoaria had an irregular cross-section, with the lumen having a varied oval shape. Curcuma zedoaria fibers had tenacity and elongation value of 3.32 gf/denier and 6.95%, respectively. Curcuma zedoaria fibers had a coefficient of friction value of 0.46. Curcuma zedoaria fibers belong to a hygroscopic fiber type with a moisture regain value of 10.29%.

Extraction and Characterization of Curcuma zedoaria Pseudo-stems Fibers for Textile Application.

The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO₂ emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

Paper aims to determinate caking paper manuscript cause through studying of the manuscript components, bio-deterioration and physio-chemical deterioration factor. It will facilitate manuscripts and paper conservators to understand paper blocking and caking phenomenon.

The manuscript condition has been diagnosed by focusing on adhesion and fossilization regions. To achieve this, some methods of analysis and examination were used, such as visual examination, digital microscopy and scanning electron microscope were used to studying surface changes. X-ray diffraction and Fourier transform infrared microscopy were used to determinate of cellulose crystallinity, ink composition and identify the binding medium.

The results revealed the use of cotton pulp, and calcium carbonate was among the fillers that were used to improve the properties of paper. The crystallization of cellulose was lower in the first and last papers than the papers located in the heart of the manuscript. The most important reasons that led to the papers caking was the presence of fungi A. niger, Cladosporium sp, Chaetomium sp, by secreting some enzymes in combination with some other factors such as difference variation in temperature and moisture.

All deterioration factors participate with each other until rule the damage circle of the papers because one factor alone cannot stick the papers. It was inferred from the examinations and analyzes that were conducted for the samples.

Additive manufacturing (AM) has been one of the most highlighted processes of the last few years. AM prints complex parts and items from 3D files regarding different materials, such as polymers. Moreover, there are different AM techniques available for polymers, such as selective laser sintering. In the SLS technology, polyamides 11 and 12 lead 88% of the market. These materials are high-cost and use an average of 50% of virgin material at each printing. It is possible to use lower rates of virgin material, but at least 30% is recommended. Low rates of virgin material decrease mechanical properties.

This study aims to evaluate the influence on the mechanical properties of the percentage of reused PA12 in parts manufactured by the SLS process. The specimens of PA12 were manufactured with a percentage of virgin/reused polymer of 50/50, 40/60, 30/70, 20/80 and 10/90. We considered three distinct printing directions to compare the mechanical properties of the specimens: horizontal, perpendicular and vertical.

The results showed that when the percentage of reused material increases, the tensile strength limit (TSL), flexural strength limit and Shore D hardness decrease. Another aspect visualized was the fragile behavior presented in the vertical specimens. In addition, DSC analysis indicated a 2% reduction of crystallinity. Scanning electron microscopy images revealed spherical voids and unfused particles of PA12 at the fracture of tensile test specimens. The material thermal history and unfused particles could decrease the material properties.

We observed that the mechanical properties, such as the TSL, flexural strength limit and hardness, decrease as the percentage of reused material increases. In addition, the process presented a printing-direction dependence, where the vertical direction presented as the more brittle between the ones used.

The purpose of this paper is to study the effect of temperature on Zn–Ni alloys in ChCl–Urea.

Based on cyclic voltammetry experiments, the deposition behavior and kinetics of the Zn–Ni alloy are studied. The nucleation process of the Zn–Ni alloy is studied in detail via chronoamperometry experiments. The effects of the deposition temperature on the microstructure, Ni content and phase composition of Zn–Ni alloy coatings are investigated via scanning electron microscopy and X-ray diffraction (XRD) combined with classical thermodynamics.

The results show that with increasing temperature, the reduction peak shifts toward a more positive electric potential, which is beneficial for the co-electric deposition process, and the diffusion coefficient is estimated. With increasing temperature, the nucleation process of the Zn–Ni alloy becomes a three-dimensional instantaneous nucleation, the typical kinetic parameters are determined using the standard 3D growth proliferation control model and the Gibbs free energy is estimated. The Zn–Ni alloy coatings are prepared via normal co-deposition. With increasing temperature, the degree of crystallinity increases, the coating gradually becomes uniform and compact and the XRD peak intensity increases.

The nucleation process of the Zn–Ni alloy at different temperatures is analyzed. The diffusion coefficient D and Gibbs free energy are calculated. The contribution of the three processes at different temperatures is analyzed. The effect of temperature on the morphology of the Zn–Ni alloy coatings is studied.

This paper aims to study the effects of inorganic CaCO₃ nanoadditives in the polylactic acid (PLA) matrix and fused filament fabrication (FFF) process parameters on the mechanical characteristics of 3D-printed components.

The PLA filaments containing different levels of CaCO₃ nanoparticles have been produced by mix-blending/extrusion process and were used to fabricate tensile and three-point bending test samples in FFF process under various sets of printing speed (PS), layer thickness (LT), filling ratio (FR) and printing pattern (PP) under a Taguchi L27 orthogonal array design. The quantified values of mechanical characteristics of 3D-printed samples in the uniaxial and the three-point bending experiments were modeled and optimized using a hybrid neural network/particle swarm optimization algorithm. The results of this hybrid scheme were used to specify the FFF process parameters and the concentration of nanoadditive in the matrix that result in the maximum mechanical properties of fabricated samples, individually and also in an accumulative response scheme. Diffraction scanning calorimetry (DSC) tests were conducted on a number of samples and the results were used to interpret the variations observed in the response variables of fabricated components against the FFF parameters and concentration of CaCO₃ nanoadditives.

The results of optimization in an accumulative scheme showed that the samples of linear PP, fabricated at high PS, low LT and at 100% FR, while containing 0.64% of CaCO₃ nanoadditives in the matrix, would possess the highest mechanical characteristics of 3D-printed PLA components.

FFF is a widely accepted additive manufacturing technique in production of different samples, from prototypes to the final products, in various sectors of industry. The incorporation of chopped fibers and nanoparticles has been introduced recently in a few articles to improve the mechanical characteristics of produced components in FFF technique. However, the effectiveness of such practice is strongly dependent on the extrusion parameters and composition of polymer matrix.

This paper aims to develop flame-retardant (FR) polyamide 12 (PA12) nanocomposite from regenerated powder via selective laser sintering (SLS), an additive manufacturing technique.

First, the morphology, processibility, thermal and mechanical properties of PA12 regenerated powder, consisting of 50 wt% new and 50 wt% recycled powder, as well as corresponding printed specimens, were evaluated to characterize the effects of previous SLS processing. Second, flame-retardant PA12 was developed by incorporating both single and binary halogen-free flame retardants into the regenerated powder.

It was found that the printed specimens from regenerated powder had much higher tensile and impact properties compared to specimens made from new powder, which is attributed to better particulate fusion and coalescence realized in higher temperature SLS printing. The effect of FRs on thermal, mechanical and flame retardant properties of the PA12 composites/nanocomposites was investigated systematically. It was found that the nanoclay, as a synergist, improved both flame-retardant and mechanical properties of PA12. UL94 standard rating of V-0 was achieved for the printed nanocomposite by incorporating 1 wt% nanoclay into 15 wt% phosphinates FR. Moreover, on average, the tensile and impact strength of the nanocomposite were increased by 26.13% and 17.09%, respectively, in XY, YZ and Z printing orientations as compared to the equivalent flame retardant composite with 20 wt% of the phosphinates FR.

This paper fulfills the need to develop flame retardant parts via SLS technology with waste feedstock. It also addresses the challenge of developing flame retardant materials without obviously compromising the mechanical properties by making use of the synergistic effect of nanoclay and organic phosphinates.

Regular monitoring of bacteria, especially Escherichia coli, in wastewater is crucial to ensure the maintenance of public health. Amperometric detection proves to be a fast, sensitive and economically viable solution for E. coli enumeration. This paper reported a prototype amperometric sensor based on PANI-ZnO-NiO nanocomposite thin films prepared by sol–gel method and irradiated with gamma ray. The purpose of this study is to investigate the sensor performance of PANI-ZnO-NiO nanocomposite thin films to detect E. coli in water.

The films were varied with different compositions of ZnO and NiO by using the formula PANI-(ZnO)_1-x-(NiO)_x, with x = 0.2, 0.4, 0.6 and 0.8. PANI-ZnO-NiO nanocomposite thin films were characterized by using X-ray diffraction (XRD) and atomic force microscopy (AFM) to study the crystallinity and surface morphology of the films. The sensor performance was conducted using the current–voltage (I-V) measurement by testing the films in clean water and E. coli solution.

XRD diffractograms show the peaks of ZnO (1 0 0) and NiO (1 0 2). AFM analysis shows the surface roughness, and the grain size of PANI-ZnO-NiO thin films decreases when the concentration ratios of NiO increased. I-V curves show the difference in current flow, where the current in E. coli solution is higher than the clean water.

PANI-(ZnO)_1-x-(NiO)_x nanocomposite thin film with the highest concentration of ZnO performed the highest sensitivity among the other concentrations, which can be used to indicate the presence of E. coli bacteria in water.

In recent years, using aberration-corrected transmission electron microscopy, the authors have achieved precisely detecting the structural evolution of passive film as well as its interface zone at atomic scale. The purpose of this paper aims to make a brief review to show the authors’ new understanding and perspective on the issue of critical factors determining stability of passive film of Fe-Cr alloy.

The introduction of single crystal enabled the authors to obtain a distinct metal/passive film interface and better characterize the structure of the interface region. The authors use aberration-corrected TEM to conduct cross-sectional observation and directly capture the details across the entire film at a high spatial and energy resolution.

Apart from the passive film itself, the interface zone, including metal/film (Me/F) interface and the adjacent metal side, is also the site which is attacked. Accordingly, the nature of the interface zone, such as microstructure, composition and atomic configuration, is one of the critical factors determining the stability of passive film.

Deciphering the critical factors determining the stability of passive film is of great significance and has been a fundamental issue in corrosion science. Great attention has been paid to the nature of the passive film itself. In contrast, the possible role of the interface between the passive film and the metal is rarely taken into account. Based on the advanced analytical tool with high spatial resolution, the authors have specified the significant role of interface structures on the macro-scale stability of passive film.

With the technological progress, high-performance materials are emerging in the market of additive manufacturing to comply with the advanced requirements demanded for technical applications. In selective laser sintering (SLS), innovative powder materials integrating conductive reinforcements are attracting much interest within academic and industrial communities as promising alternatives to common engineering thermoplastics. However, the practical implementation of functional materials is limited by the extensive list of conditions required for a successful laser-sintering process, related to the morphology, powder size and shape, heat resistance, melt viscosity and others. The purpose of this study is to explore composite materials of polyamide 12 (PA12) incorporating multi-walled carbon nanotubes (MWCNT) and graphene nanoplatelets (GNP), aiming to understand their suitability for advanced SLS applications.

PA12-MWCNT and PA12-GNP materials were blended through a pre-optimized process of mechanical mixing with various percentages of reinforcement between 0.50 wt.% and 3.00 wt.% and processed by SLS with appropriate volume energy density. Several test specimens were produced and characterized with regard to processability, thermal, mechanical, electrical and morphological properties. Finally, a comparative analysis of the performance of both carbon-based materials was performed.

The results of this research demonstrated easier processability and higher tensile strength and impact resistance for composites incorporating MWCNT but higher tensile elastic modulus, compressive strength and microstructural homogeneity for GNP-based materials. Despite the decrease in mechanical properties, valuable results of electrical conductivity were obtained with both carbon solutions until 10^–6 S/cm.

The carbon-based composites developed in this research allow for the expansion of the applicability of laser-sintered parts to advanced fields, including electronics-related industries that require functional materials capable of protecting sensitive devices against electrostatic discharge.