A major stream of post-consumer plastics is a commingled blend of polyethylenes and polypropylenes, which usually exhibits lower performance compared with that of the homopolymers due to the incompatible nature of polyethylenes and polypropylenes. Various studies have been carried out to characterize the structure, morphology, mechanical, thermal, and rheological behavior of this blend. The effect of processing, modification, and compatibilization have also been studied by various workers. This article is a review of the work done on polyethylene-polypropylene blends to help in the understanding of this important blend. ost-consumer plastics waste has become the P focus of legislation and environmental concerns.I3 The major polymeric components of these plastics waste streams are polyethylenes, polypropylenes, styrenics, polyvinyl chlorides, and polyethylene terephthalates. Separation of the plastics * To whom correspondence should be addressed.waste into an individual single polymeric type by various methods is costly and complete sorting is economically nonviable and sometimes impossible. Hence in the field of plastics recycling, we are usually faced with a recycled product of a commingled mixture. Due to the incompatible nature of most polymer^,^,^ the commingled polymeric mixtures are poor in their mechanical performance, aging behavior, and resistance toward thermal and chemical environment. In the case of recycling of polyolefins, a commingled blend of polyethylenes (consisting of linear low, low, and

Electricity demand has grown over the past few years and will continue to grow in the future. The increase in electricity demand is mainly due to industrialization and the shift from a conventional to a smart-grid paradigm. The number of microgrids, renewable energy sources, plug-in electric vehicles and energy storage systems have also risen in recent years. As a result, future electricity grids have to be revamped and adapt to increasing load levels. Thus, new complications associated with future electrical power systems and technologies must be considered. Demand-side management (DSM) programs offer promising solutions to these issues and can considerably improve the reliability and financial performances of electrical power systems. This paper presents a review of various initiatives, techniques, impacts and recent developments of the DSM of electrical power systems. The potential benefits derived by implementing DSM in electrical power networks are presented. An extensive literature survey on the impacts of DSM on the reliability of electrical power systems is also provided for the first time. The research gaps within the broad field of DSM are also identified to provide directions for future work.

Electrical networks across the globe are gearing towards environmentally friendly operation with many renewable sources being introduced. Among them, the popularity of electrical generation by wind has gained the most ground. Wind, as one of the meteorological conditions, also has high influence on line ratings and such manner of operating the line is known as dynamic thermal rating (DTR) system. Seeing this relationship, it is intuitively important to investigate the reliability of a electrical network incorporating DTR and wind farm. Hence, the objective of this paper is to propose a methodology that can perform this task. In the methodology, sequential Monte Carlo (SMC) simulation was performed due to time dependencies of line ratings and wind power. As a result, modeling of these time-series data was performed using the auto-regressive and moving-average (ARMA) model. Moreover, correlations between line rating and wind power were also considered to provide a practical approach to the modeling. Results have shown that DTR system is able to increase network reliability and allows for higher wind energy penetration.

Electricity plays a crucial role in the well-being of humans and is a determining factor of the economic development of a country. Electricity issues have encouraged researchers to focus on improving power availability and quality along with reliability. This pursuit has increasingly raised the intention to integrate renewable energy (RE) into power systems to curb the problem of energy deficiency. However, intermittency in the sources of RE supply coupled with fluctuating changes in demand with respect to time has induced high risk in maintaining system reliability in terms of providing adequate supply to consumers. Whilst an energy storage system (ESS) is not another source of electricity, it is proven to be effective and viable in solving the aforementioned issues. Thus, this paper comprehensively reviews the development of ESS technologies and discusses the benefits and real-life applications of these technologies. The concept of reliability in power systems is also explored to provide an improved understanding of this study. Lastly, notable studies that have addressed the reliability impact of ESSs on power systems are discussed. This review paper therefore is expected to provide a critical analysis of ESS developments, as well as recognize their research gaps in terms of reliability studies in modern RE-integrated power networks.

SynopsisThe structure and mechanical properties of blends of low-density polyethylene and isotactic polypropylene were studied. The blends behaved like a simple composite obeying the rule of mixture for the modulus dependence on composition. Tensile strength of the LDPE was enhanced with the addition of PP but elongation at break was drastically reduced for all blend compositions. Studies with WAXD, hot-stage microscope, and DSC indicated lack of interaction between the LDPE and the PP. The crystallographic structure of LDPE and PP remained unchanged. However, the spherulite size of the PP was found to be reduced in the presence of LDPE, possibly due to an increase in nucleation density.

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