Curing Characteristics,Fatigue and Hysteresis Behaviour of Feldspar Filled Natural Rubber Vulcanizates

Curing characteristics, fatigue, and hysteresis behaviour of feldspar filled SMR L vulcanizates and feldspar filled ENR 50 vulcanizates were studied. Two different types of natural rubber, SMR L and ENR 50 having 0 and 50 mol% of epoxide groups were used. The feldspar filled natural rubber vulcanizates were compared at similar filler loading which were used at 0, 10, 20, and 30 phr of filler loading. The curing characteristics such as scorch time (t ₂) and cure time (t ₉₀) slightly increased with increasing feldspar loading for both rubber vulcanizates. Besides t ₂ and t ₉₀, maximum torque (M _HR) significantly increased for both rubbers with increasing feldspar loading. The fatigue test showed that fatigue life decreased with increasing extension ratio, strain energy and filler loading. As the filler loading increased, the poor wetting of the feldspar by the rubber matrix gave rise to poor interfacial adhesion between filler and rubber matrix. Results also indicate that the vulcanizates with the highest feldspar loading exhibited the highest hysteresis. The feldspar filled SMR L vulcanizates showed higher fatigue life and lower hysteresis compare to feldspar filled ENR 50 vulcanizates.     

Review: Single Screw Extruder in Particulate Filler Composite

This review is designed to be a comprehensive source for single screw extruder research in the scope of particulate filled composite. This review includes factors effecting processing of particulate filled composite using a single screw extruder. The mixing requirements for a particulate filled composite analyzed and discussed in terms of single screw extrusion. The factors for achieving effective mixing of this type of composite are also discussed.     

The Influence of Green Surface Modification of Oil Palm Mesocarp Fiber by Superheated Steam on the Mechanical Properties and Dimensional Stability of Oil Palm Mesocarp Fiber/Poly(butylene succinate) Biocomposite

In this paper, superheated steam (SHS) was used as cost effective and green processing technique to modify oil palm mesocarp fiber (OPMF) for biocomposite applications. The purpose of this modification was to promote the adhesion between fiber and thermoplastic. The modification was carried out in a SHS oven at various temperature (200–230 °C) and time (30–120 min) under normal atmospheric pressure. The biocomposites from SHS-treated OPMFs and poly(butylene succinate) (PBS) at a weight ratio of 70:30 were prepared by melt blending technique. The mechanical properties and dimensional stability of the biocomposites were evaluated. This study showed that the SHS treatment increased the roughness of the fiber surface due to the removal of surface impurities and hemicellulose. The tensile, flexural and impact properties, as well as dimensional stability of the biocomposites were markedly enhanced by the presence of SHS-treated OPMF. Scanning electron microscopy analysis showed improvement of interfacial adhesion between PBS and SHS-treated OPMF. This work demonstrated that SHS could be used as an eco-friendly and sustainable processing method for modification of OPMF in biocomposite fabrication.     

Extraction and physicochemical properties of low free fatty acid crude palm oil

Response surface methodology was applied to optimize the pre-treatment of oil palm (Elaeis guineensis) fruit spikelets before oil extraction. The treatment applied was drying at different times and temperatures. The dried spikelets were then subjected to mechanical processes and crude oil was extracted. A central composite design was employed to study the responses, namely percentage of free fatty acids (FFA) and oil yield, and the optimum conditions for minimum FFA and maximum oil yield were identified from their respective contour plots. It was concluded that the pre-treatment should be carried out for 12.8 h at 66.8 °C. Under the optimum conditions, the corresponding response values for FFA and oil yield were 1% and 33.6%, respectively. Some of the physicochemical properties of the extracted oil were then determined. The low free fatty acid crude palm oil exhibited good physicochemical properties and could be useful for industrial applications.     

Biogeography-based optimisation for flexible manufacturing system scheduling problem

Biogeography-based optimisation (BBO) algorithm is a new evolutionary optimisation algorithm based on geographic distribution of biological organisms. With probabilistic operators, this algorithm is able to share more information from good solutions to poor ones. BBO prevents the good solutions to be demolished during the evolution. This feature leads to find the better solutions in a short time rather than other metaheuristics. This paper provides a mathematical model which integrates machine loading, part routing, sequencing and scheduling decision in flexible manufacturing systems (FMS). Moreover, it tackles the scheduling problem when various constraints are imposed on the system. Since this problem is considered to be NP-hard, BBO algorithm is developed to find the optimum /near optimum solution based on various constraints. In the proposed algorithm, different types of mutation operators are employed to enhance the diversity among the population. The proposed BBO has been applied to the instances with different size and degrees of complexity of problem adopted from the FMS literature. The experimental results demonstrate the effectiveness of the proposed algorithm to find optimum /near optimum solutions within reasonable time. Therefore, BBO algorithm can be used as a useful solution for optimisation in various industrial applications within a reasonable computation time.     

Development of decision support system for fastener selection in product recovery oriented design

Among the important strategies in sustainable product development is by maintaining product recovery and prolonging product life which are highly dependent on the ease of disassembly. When considering the design for disassembly, there are many fastener-associated factors to be considered such as structural, disassembly process and the pre-disassembly process. There are very few designs for disassembly methods that support the selection of fasteners for design for disassembly (DfD) concepts. Most of the tools developed are more applicable during later stages of the design process when more product information is available. The process of selecting a fastener for its functional characteristics itself is often vague. Additionally, the requirements for disassemblability further complicate the process. This paper proposes the development of a multi-criteria decision making model to assist designers in selecting fasteners for DfD. PROMETHEE was used to build a decision-making model to help the designers in selecting the fasteners that could perform their intended functions with ease of disassembly. A design case study is described to reflect the usefulness of the fasteners selection model.     

Methane emission by sectors: A comprehensive review of emission sources and mitigation methods

The global threat caused by increasing surface temperature has led to negative climate changes. One of the greenhouse gases responsible for this global warming is methane. It is emitted naturally and anthropogenically from different sources and its concentration in the atmosphere has assumed alarming proportions. Its devastating consequences on climate change and atmospheric chemistry have made it to be a focus of intense scrutiny and study. The anthropogenic sources of its emissions are generally grouped under three sectors of agriculture, energy and waste. The past emission trends of methane from these sectors are investigated through their sources while mitigation and abatement strategies are suggested. It is observed that the agricultural sector emits the highest amount of methane, followed by the energy and waste sectors, respectively.     

Powder material parameters establishment through warm forming route

This paper presents the establishment of the properties of powder materials through experimentation at elevated temperature ranging from room temperature (30 °C) to 150 °C. Uniaxial die compaction experiments were conducted to establish the powder properties such as densification, Young’s modulus, spring-back, plastic index, elastic index, and plastic hardening coefficient. Shearing experiments were conducted to establish the temperature dependent friction coefficient. Iron powder ASC 100.29, manufactured by Höganäs AB Company was used during the experiment. The results showed that the deformation properties of powder materials especially iron powder are temperature dependent. The values of some properties are increased as the compaction temperature increased and vice versa.     

A note on “A multi-objective genetic algorithm for solving assembly line balancing problem”

Assembly line balancing has a considerable place in industrial importance. Hence, a lot of researchers are interested in this subject and several papers have been published so far. Many exact, heuristic, metaheuristic, and hybrid approaches have been used to solve this type of problems. Recently Ponnanbalam et al. (Int J Adv Manuf Technol 16:341–352, 2000) have considered a multi-objective genetic algorithm utilizing several simple heuristic rules for solving the simple assembly line balancing problems, one of these rules was “rank positional weight (RPW)” originally published in Helgeson and Birnie (J Ind Eng 12(6):394–398, 1961). Through providing two possible justifications, this note suggests that the mentioned rule can be mistakenly utilized and some revisions in Ponnanbalam et al. (Int J Adv Manuf Technol 16:341–352, 2000) seem to be necessary.