A two-level full factorial design 22 with three replications was employed to assess the effect of the incorporation of PSF into the epoxy matrix and the surface treatment of carbon fibers on the work of adhesion (WA) and the interfacial shear strength (IFSS) of carbon fiber–epoxy composites. The IFSS was determined using the microbond (or microdrop) micromechanical test, and the work of adhesion was estimated using two different procedures: (1) using the Owens and Wendt method, and (2) from the Dupre–Young expression using the contact angle θ of a cured epoxy resin on a single carbon fiber and the surface energy of the cured epoxy resin. It was found that the treatment of the carbon fiber with the silane-coupling agent appreciably increases its polar component because of the nitric acid oxidation and the chemisorption of the silane-coupling agent onto the carbon fiber surface. Also, the O=S=O group present in the polysulfone chain resin fairly increases the polar component of the epoxy–PSF blend. The results show that the wetting of the silane-treated carbon fiber by the thermoplastic-modified epoxy resin is better, thus increasing the fiber–matrix adhesion. It was also found that there is a similarity between the trends of both, the IFSS and the WA results. Also, from the ANOVA results it was also seen that both the incorporation of the PSF to the epoxy matrix and the surface treatment of the carbon fibers and their interaction were statistically significant to the IFSS and the WA.

본 리뷰 논문은 식품 산업에서 나노 기술의 활용에 관한 보고이다. 식품 병원균에 대한 항균 활성을 갖는 생리 활성 성분은 식품 보존시 효율성을 향상시키고 보존성을 증진시키기 위해 나노입자(NPs)로 캡슐화된다. 그러나, 이러한 NPs는 인간에게 생체 적합성과 무독성을 지녀야 된다. 식품 보존분야의 발전은 일부 산업 분야에서 식품 포장용 NPs의 개발을 가져왔다. 식품 산업 분야에서 가장 일반적으로 사용되는 NPs 그룹은 금속 산화물이다. 산화 아연과 이산화 티타늄 같은 금속 산화물 NPs는 식품 재료에 서 항균 활성을 나타내기 때문에, NPs는 강화된 기능적 특성으로 식품 보존에 사용될 수 있다. 식품 영양과 관능적 특성과 관련된 나노 기술의 적용은 나노 기반 식품 제조 및 보존에 관한 안전규제를 중심으로 간략하게 정리하였다.

This work addresses the development of the astronomical observatory all through history, from an architectural point of view, as a building in relation to the observing instruments and their functioning as a heterogeneous work center. We focused on 32 observatories (in the period 1259–2007) and carefully analyzed the architectures. Considering the impact of the construction itself or its facilities on the results of the research (thermal or structural stability, poor weather protection, turbulence, etc.), there is little attention paid to theories or studies of the architectural or construction aspects of the observatories. Therefore, this work aims to present a theoretical-critical contribution that, at least, invites the reflection of those involved in the development of astronomical observatories in the future.

This study focused on the development of Fe–Co/kaolin catalyst by a wet impregnation method. Response surface methodology was used to study the influence of operating variables such as drying temperature, drying time, mass of support and stirring speed on the yield of the catalyst. The catalyst composite at best synthesis conditions was then calcined in an oven at varied temperature and time using 22 factorial design of experiment. The catalyst with optimum surface area was then utilized to grow carbon nanofiber (CNF) in a chemical vapour deposition (CVD) reactor. Both the catalyst and CNF were characterized using high-resolution scanning electron microscopy, high-resolution transmission electron microscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy. On the influence of operating variables on the yield of catalyst, the results showed that an optimum yield of 96.51% catalyst was obtained at the following operating conditions: drying time (10 h), drying temperature (110 °C), stirring speed (100 rpm) and mass of support (9 g). Statistical analysis revealed the existence of significant interactive effects of the variables on the yield of the catalyst. The HRSEM/XRD/BET/TGA analysis revealed that the particles are well dispersed on the support, with high surface area (376.5 m2/g) and thermally stable (330.88 °C). The influence of operating parameters on the yield of CNF was also investigated and the results revealed an optimum yield of 348% CNF at the following operating conditions: reaction temperature (600 °C), reaction time (40 min), argon flow rate (1416 mL/min) and acetylene/hydrogen flow rate (1416 mL/ min). It was found from statistical analysis that the reaction temperature and acetylene/hydrogen flow rates exerted significant effect on the CNF yield than the other factors. The contour and surface plots bi-factor interaction indicated functional relationship between the response and the experimental factors. The characterization results showed that the synthesized CNF is thermally stable, twisted and highly crystalline and contain surface functional groups. It can be inferred from the results of various analyses that the developed catalyst is suitable for CNF growth in a CVD reactor.

The IMO Standard Marine Communication Phrases (SMCP) has been established purposely to enhance the greater safety of vessel’s navigation by standardizing the language used among seafarers. However, accidents are still occurred due to communication failures among onboard merchant vessels’ crews. It is worth mentioning that the major cause of marine accidents is human error (80%) where one-third from it was due to communication failures. Ineffective communication, different culture and language among seafarers onboard are some instigators of human error that lead to accidents in marine operations. Therefore, the primary aim of this paper is to investigate and evaluate the causal factors that contributes to communication failures onboard merchant vessels. Then, this paper recommends possible solutions for minimizing the communication failures among seafarers. To achieve this research objectives, two decision-making tools which are the Analytical Hierarchy Process (AHP) and Evidential Reasoning (ER) was applied. Data and judgments are obtained from domains experts from four marine training providers and eight shipowners in Malaysia. The result has shown that lack of SMCP knowledge, prejudice and dialect varieties are the most significant factors that contribute to the communication failures onboard merchant vessels. Few suggestions and opinions from the experts are proposed in this paper. This research can assist marine training providers and shipowners to identify and evaluate the causal factors of communication failures thus corrective action can be taken.