This paper focused on thermal conductivity and viscosity of deionised water and ethylene glycol-based nanofluids at three different temperatures (6C, 25C and 40C). For the preparation of nanofluids, a two-step method, comprised of homogenisation and sonication, was used on a mixture of MWCNT-OH, PVP and the base fluid. The results revealed that thermal conductivity was enhanced by about 8.86% for 0.8 wt% deionised water-based MWCNT-OH nanofluid, and by 5.37% for 0.2 wt% ethylene glycol-based MWCNT-OH nanofluid. Meanwhile, in viscosity test, the highest temperature of 40C exhibited lowest viscosity. This phenomenon happened only with ethylene glycol-based nanofluid, whilst the data on the viscosity of deionised water-based nanofluid was inconsistent at certain nanofluid concentrations . In conclusion, addition of MWCNT-OH into base fluid enhanced base fluid performance , giving it the potential to be used in cooling system applications.

A major problem being faced by existing coolants is the limited amount of heat that can be absorbed by the fluids. An innovative way to overcome this limitation is by utilizing a nano-coolant as a heat transfer medium in a cooling application. This paper was aimed at formulating an efficient nanofluid from Pyrograf III HHT24 carbon nanofibers (CNF) in a base fluid consisting of deionized water (DI) and ethylene glycol (EG) with polyvinylpyrrolidone (PVP) as the dispersant. The experiment was conducted by setting the variable weight percentage of CNF from 0.1 wt% to 1.0 wt%, with the base fluid ratio of 90:10 (DI:EG) weight percent. Then, the thermal properties of the formulated nanofluids were investigated. The test on the thermal conductivity of the nanofluids showed that the highest thermal conductivity of 0.642 W/m.K in this experiment was produced when the concentration of nanofluid is 0.5 wt% at a temperature of 40°C. Experimental investigations into the forced convective heat transfer performance of the CNF-based nanofluid in a laminar flow through a mini heat transfer test rig showed that the presence of nanoparticles enhanced the heat transfer coefficient as opposed to the original base fluid. The highest heat transfer coefficient was reported using nanofluid with a concentration of 0.6 wt% at 40°C. The enhancement of the heat transfer coefficient was due to the higher thermal conductivity value. The Nusselt number was also calculated and presented in this paper. This study showed that the CNF-based nanofluids have a huge potential to replace existing coolants in electronic cooling applications. Thus, in order to commercialize nanofluids in practice, more fundamental studies are needed to understand the crucial parameters that affect their thermal characteristics.

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This paper is concern about the students’ attitude from Faculty Business and Management in UiTM Pahang Raub Campus, towards the Statistics course. The objective of this study is to determine the mean difference of students’ performance between gender, to identify students' attitude towards Statistics course and to profile the students’ attitude towards Statistics course. The survey was retrieved from the Survey of Attitude Towards Statistics (SATS) instrument. The independence T- test and Mean Score was used to retrieve the results. The results show a difference of test score between gender, which female students show a greater performance compared to male students. In addition, students demonstrate positive attitude towards Statistics course through Mean Score of the component (Affective, Effort, Cognitive Ability and Value). Even though female students show an outstanding performance than male students in test score, however through profiling male students tend to be more positive in attitude towards the Statistics course.

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