Thermionic energy converter (TEC) is a heat engine that generates electricity directly using heat as its source of energy and electron as its working fluid. Despite having a huge potential as an efficient direct energy conversion device, the progress in vacuum-based thermionic energy converter development has always been hindered by the space charge problem and the unavailability of materials with low work function. It is only recently that researchers have started to look back into this technology as recent advances in manufacturing technology techniques have made it possible to solve these problems, making TECs a viable option in replacing current energy production systems. The focus of this paper is to review the challenges of producing efficient and practical TECs, along with recent findings and developments in mitigating these challenges. Furthermore, this paper looked into potential applications of TECs, based on recent works and technologies, and found that, with certain improvements, it can be applied in many sectors.

Purpose: The purpose of this study is to describe cosmetics purchase behavior of young, educated Muslim females in Malaysia and to explore its relationship with certain potential antecedents. Design/methodology/approach: This study uses a survey on a sample of female consumers from four higher education institutions in the urban area of Bangi Selangor, Malaysia. From their respective institutions, 150 respondents were selected through the purposive sampling method. Self-administered questionnaire has been used to gather information from the respondents. The survey data were analyzed using descriptive, t-test and correlation analyses to accomplish the study objectives. Findings: The study indicates that millennial Muslim cosmetic purchase behavior falls under the “Limited Decision Making” classification. The classification is due to the pattern of pro-active behaviors exhibit through the information search for details about ingredients, halal clue, countries of origin, health safety guarantee and the benefits of the cosmetic products. Young, educated female consumers adore branded cosmetic items and show willingness to accept higher prices for the branded items. Despite brand consciousness, they demonstrate a relatively high concern on the halalness of the product. Based on the correlation analysis, all variables were found to be significant and the most significant of them was brand. Research limitations/implications: Millennial consumers are information technology savvy and have access to vast information about products. As a result, the findings reiterate that millennial consumers demonstrate different purchase behavior, which is worth exploring by future researchers. In addition, other latent antecedents such as religiosity and world view are worth including in future studies. Practical implications: Cosmetic manufacturers and marketers must ensure that their products signal positive images to fit the expectations of young and educated Muslim consumers. Although brand conscious, such consumers demonstrate prudent behavior in terms of searching for halalan and toyyiban products. Originality/value: This study adds value in the area of halal product marketing because of two unique focuses. First, it examines the purchase of cosmetic products, which are relatively understudied compared to halal food. Second, it considers the perspectives of educated Muslim millennials, who are expected to demonstrate more specific purchase behaviors than a generalized millennial group. Therefore, the originality of this study revolves around the consideration of these two aspects, which are relevant to contemporary business marketing discussions.

Biodiesel produced from any fat or oil blended with diesel in different percentage has emerged as an alternative diesel and renewable energy. In Malaysia, crude palm oil (CPO) is the most preferable feedstock to be converted into biodiesel via transesterification process. This study aimed to investigate the effects of storage duration of variant blending biodiesel ratio under different storage temperature on fuel properties and exhaust emissions. The biodiesel samples were stored in clinical compartment, at different temperatures and were monitored at regular interval over a period of 60 days. Blending of biodiesel are varied from 5vol%(B5)∼ 45vol%(B45) and storage temperature from 5°C∼30°C. The tests subject presented in this research is performed according to ASTM D6751 and EN 14214 standard. The effects of storage conditions on properties of biodiesel such as density, kinematics viscosity, acid value, water content and flash point of biodiesel were discussed in detail. Furthermore, the experimental with burner system was carried out to observe the influences of storage method on emission aspects. Analysis of the measurement performed shows that the biodiesel density, viscosity and carbon monoxide are affected by storage duration and storage temperature. High blending ratio exhibits relative variant in emissions production due to the higher oxygenated fuel