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The utilisation of food waste/by‐products helps to increase produce recovery and enhances nutrition in low‐cost food without any appreciable increase in product cost. The storage behaviour of the product must be studied before commercialisation of the product. This paper aims to focus on this process.

Extrudates (25 g) prepared under optimised conditions of proportion (rice flour, pulse powder and carrot pomace), moisture content, screw speed and die temperature, were sealed using a polythene sealing machine in LDPE bags and aluminium laminated LDPE bags. The bags were then stored for six months in an incubator at temperature of 38±2°C to evaluate the stability of the product. The extrudates were analysed for change in colour, hardness, moisture content and sensory characteristics.

Zero‐ and first‐order models were fitted for prediction purposes. The minimum overall change in color ΔE value, minimum increase in moisture content and minimum increase in hardness was observed in aluminium laminated LDPE bags. The zero order model better predicted the variation of L*, b*, ΔE, moisture content and hardness during storage, whereas first order model was better fitted for the a* value.

The carrot pomace has the potential to be used as a food ingredient that enhances the nutritional attributes of products along with a reduction in cost. Extruded products were successfully developed in the laboratory using carrot pomace as one of the ingredients. This study evaluates the kinetic changes during the storage of carrot pomace based extruded snacks.

The purpose of this paper is to study a new method with which multi‐walled carbon nanotubes (MWNTs) can be dispersed and aligned in low density polyethylene (LDPE) for improving its mechanical properties.

Dispersion and alignment of MWNTs in LDPE matrix are enhanced by ultrasonic vibration, solution casting and melt mixing and flow moulding method. The properties of the composite are characterised using scanning electron microscopy, tensile testing machine and the Izod impact testing machine.

It is found that MWNTs in LDPE achieve some dispersion and alignment resulting in improvement in LDPE's strength and toughness.

Polymer/CNTs nanocomposites are expected to have good process ability of the polymers and high mechanical and functional properties of the CNTs. Enhancing dispersion and alignment of MWNTs in the polymer matrix will promote and expand the applications and development of polymer/MWNTs nanocomposites.

The method that enhances MWNTs dispersion and alignment in LDPE matrix provides a new way for alignment of other CNTs in polymer matrix.

To develop a method for the preparation of multi‐walled carbon nanotube reinforced low density polyethylene (LDPE) composites (MWNTs/LDPE), based on ultrasonic vibration, solution casting and melt mixing.

The preparation for MWNTs/LDPE composites was carried out by vibration of carbon nanotubes (CNT), solution casting and melt mixing for MWNTs and LDPE. The physical chemical properties of the composites were characterised using a variety of techniques including scanning electron microscopy, resistance and tensile measurement.

It was found that the preparation method reported had significantly improved the dispersion of multi‐walled carbon nanotubes (MWNTs) in LDPE matrix, resulting in the improvement of tensile strength of the composite. The percolation of MWNTs in LDPE matrix was between 10 and 15 wt% (10¹⁶‐10⁸ Ω cm).

The preparation method reported addressed a problem concerning the dispersion of CNT in polymer matrix. The method developed provided a practical and effective solution to such a problem.

The preparation method for MWNTs/LDPE composites involving vibration of CNT, solution casting and melt mixing for MWNTs and LDPE was novel. The method could be adapted for use in industrial scale.

The aim of this paper is to evaluate the storage stability of improved dambu, a steamed granulated dumpling product generally made from millet, was produced from maize (Zea mays), millet (Pennisetum glaucum), sorghum (Sorghum bicolor) and acha (Digitaria exilis). It is a popular mid‐day meal of the Fulanis of Nigeria normally sprinkled into fermented skimmed milk or whole milk and sugar may be added to taste.

Improved dambu was prepared in the laboratory using decorticated clean cereal grains which were pulverished into coarse particles, mixed with spices, preservative (sorbic acid) and water and steamed for 20 min. The improved dambu products were packaged in low‐density polyethylene (LDPE), LDPE with plastic and LDPE with paperboard and stored at room temperature (25 ^○C) for six days. Analysis was carried out on the products following documented and established procedures.

Data obtained indicated that during storage, pH decrease was observed while titratable acidity increased for improved dambu products. The microbial load (cfu/g) increased with storage time for all the products packaged in LDPE, LDPE with plastic and LDPE with paperboard. Dambu has a limited storage life of one day at room temperature (25 ^○C) and four days with 0.2 per cent (w/w) sorbic acid as preservative. Micro‐organisms of significance in the products are Aspergillus sp, Penicillum sp, Candida sp, Staphylococcus aureus and Enterobacter aerogenes. The nature of the microflora suggested that dambu is a good substrate for fungal growth. In the comparative study of dambu products with and without sorbic acid, there was no significant difference in the mean scores for all the assessed parameters.

The consumption of dambu from different cereal grains is encouraged especially where a particular cereal is off season. The shelf‐life of dambu was extended to four days by using 0.2 per cent (w/w) sorbic acid as preservative and packaged in LDPE with plastic and LDPE with paperboard. Further research should be carried out to extend the shelf‐life more.

The findings have suggested that dambu is necessary to cereal industry and baby foods (weaning foods).

The results of this research contributes to the knowledge of cereal meals, especially those that are indigenous to Nigeria and West Africa.

The purpose of this study is to numerically examine the heat transfer and transport of space charges in the solid insulating materials [low density polyethylene (LDPE), flame retardant type 4 (FR4), Polytetrafluoroethylene (PTFE)] using the transmission line modeling (TLM) method. Besides, a comprehensive study is performed on the mutual influences of heat transfer and space charges transport within the solid dielectric bulk.

The obtained governing equations including continuity and circuit equations are coupled with heat transfer equations, and they are solved via fourth-order Runge–Kutta method.

The electric potential and field, current density and temperature distribution are calculated. It is shown that compared with FR4 and PTFE, the temperature increment rate in LDPE is much lower. Moreover, the heat transfer in the solid insulating materials bulk increases the homo-charges density and temperature in the vicinity of electrodes. Hence, the reduction in electric field is reflected in the potential deformations in the proximity of electrodes. Furthermore, where the electric field is maximized, the temperature is minimized.

This study is restricted to two-dimensional problems.

Interestingly, because of the lower temperature in LDPE, the current density and their increment rates in LDPE are much lower than that in FR4 and PTFE dielectric materials.

Purpose – This purpose of the research is to investigate the process of manufacturing LDPE recycle thermoplastic composites with reinforcement oil palm empty fruit bunch (OPEFB) biomass microfillers.

Design/Methodology/Approach – Methods of physical and chemical modification of OPEFB fibers into the LDPE matrix and the addition of some compatibilizer such as MAPE and xylene process through melt blending can improve mechanical properties, electrical properties, biodegradability, and improve the morphology of composites.

Research Limitations/Implications – These composites are prepared by the following matrix ratio: filler (70:30)% and filler size (63, 75, 90, and 106) μm. The LDPE plastic is crushed to a size of 0.5–1 cm, then pressed with hot press free heating for 5 min and with a pressure of 10 min at 145 °C. Based on the characterization obtained, the tensile strength and the high impact on the use of 106 μm filler is 13.86 MPa and 3,542.6 J/m², and thermal stability indicates the degradation temperature (T₀) 497.83 °C. FT-IR analysis shows the presence of functional groups of cellulose and lignin molecules derived from TKKS collected in the composite.

Practical Implications – Based on the characterization obtained, this composite can be applied as furniture material and vehicle dashboard.

Originality/Value – Composites obtained from recycle of LDPPE plastics waste has some advantages such as good compatibility and high tensile strength. This composite used the OPEFB filler whose size is in micrometer, and so this product is different from other products.

Purpose – This work aims to study the treatment of adsorbant on the increasing liquid hydrocarbon quality produced by pyrolysis low density polyethylene (LDPE) plastic waste at low temperature. The hydrocarbon distribution, physicochemical properties and emission test were also studied due to its application in internal combustion engine. This research uses pure Calcium carbonate (CaCO₃) and pure activated carbon as adsorbant, LDPE type clear plastic samples with control variable that is solar gas station.

Design/Methodology/Approach – LDPE plastic waste of 10 kg were vaporized in the thermal cracking batch reactor using LPG 12 kg as fuel at range temperature from 100 to 300°C and condensed into liquid hydrocarbon. Furthermore, this product was treated with the mixed CaCO₃ and activated carbon as adsorbants to decrease contaminant material.

Findings – GC-MS identified the presence of carbon chain in the range of C6–C44 with 24.24% of hydrocarbon compounds in the liquid. They are similar to diesel (C6–C14). The 30% of liquid yields were found at operating temperature of 300°C. The calorific value of liquid was 46.021 MJ/Kg. This value was 5.07% higher than diesel as control.

Originality/Value – Hydrocarbon compounds in liquid produced by thermal cracking at a low temperature was similar to liquid from a catalytic process.

This study considers both a single and multi‐mode viscoelastic analysis for wire‐coating flows. The numerical simulations utilise a finite element time‐stepping technique, a Taylor‐Petrov‐Galerkin/pressure‐correction scheme employing both coupled and decoupled procedures between stress and kinematic fields. An exponential Phan‐Thein/Tanner model is used to predict pressure‐drop and residual stress for this process. Rheometrical data fitting is performed for steady shear and pure extensional flows, considering both high and low density polyethylene melts. Simulations are conducted to match experimental pressure‐drop/flowrate data for a contraction flow. Then, for a complex industrial wire‐coating flow, stress and pressure drop are predicted numerically and quantified. The benefits are extolled of the use of a multi‐mode model that can incorporate a wide‐range discrete relaxation spectrum to represent flow response in complex settings. Contrast is made between LDPE and HDPE polymers, and dependency on individual relaxation modes is identified in its contribution to overall flow behaviour.

This paper aims to perform an experimental investigation on the impact strength, compressive strength, tensile strength and flexural strength of fly ash-based green composites and to compare with these polyvinyl chloride (PVC), high density polyethylene (HDPE) and low density polyethylene (LDPE).

Fly ash-based polymer matrix composites (FA-PMCs) were fabricated using hand layup method. Composites containing 100 g by weight fly ash particles, 100 g by weight brick dust particles and 50 g by weight chopped glass fiber particles were processed. Impact strength, compressive strength, tensile strength and flexural strength of composites have been measured and compared with PVC, HDPE and LDPE. Impact strength of the FA-PMC is higher than that of PVC, HDPE and LDPE. Structural analysis of pipes, gears and axial flow blade was verified using ANSYS. Barlou’s condition for pipes, Lewis–Buckingham approach for gears and case-based analysis for axial flow blades were carried out and verified.

Pipes, gears and axial flow blades made form fly ash-based composites were found to exhibit improved thermal resistance (i.e. better temperature independence for mechanical operations), higher impact strength and longer life compared to those made from PVC, HDPE and LDPE. Moreover, the eco-friendly nature of the raw materials used for fabricating the composite brings into its quiver a new dimension of appeal.

Experimental investigation on the impact strength, compressive strength, tensile strength and flexural strength of fly ash-based green composites has not been attempted yet.

The purpose of this paper is to optimize and improve a bipolar charge transport (BCT) model used to simulate charge dynamics in insulating polymer materials, specifically low-density polyethylene (LDPE).

An optimization algorithm is applied to optimize the BCT model by comparing the model outputs with experimental data obtained using two kinds of measurements: space charge distribution using the pulsed electroacoustic (PEA) method and current measurements in nonstationary conditions.

The study provides an optimal set of parameters that offers a good correlation between model outputs and several experiments conducted under varying applied fields. The study evaluates the quantity of charges remaining inside the dielectric even after 24 h of short circuit. Moreover, the effects of increasing the electric field on charge trapping and detrapping rates are addressed.

This study only examined experiments with different applied electric fields, and thus the obtained parameters may not suit the experimental outputs if the experimental temperature varies. Further improvement may be achieved by introducing additional experiments or another source of measurements.

This work provides a unique set of optimal parameters that best match both current and charge density measurements for a BCT model in LDPE and demonstrates the use of trust region reflective algorithm for parameter optimization. The study also attempts to evaluate the equations used to describe charge trapping and detrapping phenomena, providing a deeper understanding of the physics behind the model.