Nafion-functionalized multiwalled carbon nanotubes (MWCNT-Nafion) are prepared through an ozone-mediated process. The chemical structure of MWCNT-Nafion is characterized by Raman spectroscopy, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. Nafion chains covering on the outer surfaces of MWCNTs in MWCNT-Nafion is observed in high-resolution transmission electron micrographs. The Nafion fraction of MWCNT-Nafion is about 12 wt%. MWCNT-Nafion is effective to prepare Nafion/MWCNT-Nafion composite membranes for proton exchange membrane fuel cells. Compared to the pristine Nafion membrane, the composite membrane with a MWCNT-Nafion loading of 0.05 wt% (N/MN-0.05) exhibits an 1.5-fold increase of mechanical strength and a five-fold increase of proton conductivity. In single cell tests, the current density at 0.6 V and the maximum power density measured with the N/MN-0.05 composite membrane are 1556 mA cm À2 and 650 mW cm À2 , respectively. Both of the values are 1.5-times the values measured with a pristine Nafion membrane.

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This research aims to study the unique factors of virgin coconut oil (VCO) compared with coconut oil (i.e., coconut oil processed through heating the coconut milk and palm oil sold on the market). Its novelty is that it (VCO) contains lactic acid bacteria and bacteriocin. Lauric acid content was analyzed by the Chromatographic Gas method. Isolation of lactic acid bacteria (LAB) was conducted by the dilution method using MRSA + 0.5% CaCO3 media. Iodium number, peroxide, and %FFA were analyzed using a general method, and isolation bacteriocin by the deposition method using ammonium sulfate. In addition, macromolecular identification was conducted by 16S rRNA. VCO was distinguished by a higher content of lauric acid (C12:0) 41%–54.5% as compared with 0% coconut and 0, 1% palm oil, respectively. The VCO also contains LAB, namely Lactobacillus plantarum and Lactobacillus paracasei, and can inhibit the growth of pathogenic bacteria, such as Pseudomonas aeruginosa, Klebsiella, Staphylococcus aureus, S. epidermidis, Proteus, Escherichia coli, Listeria monocytogenes, Bacillus cereus, Salmonella typhosa and bacteriocin. Comparison with VCO is based on having a high content of lauric acid, 54%, and LAB content. The difference between VCO and coconut oil and palm oil is fatty acids. In VCO there are lauric acid and stearic acid, namely lauric acid VCO (A) 54.06%, VCO (B) 53.9% and VCO (C) 53.7%. The content of stearic acid VCO (A) is 12.03%, VCO (B) 12.01% and VCO (C) 11.9%. Coconut oil contains a little lauric acid, which is 2.81%, stearic acid 2.65% and palmitic acid 2.31%. Palm oil can be said to have very little lauric acid, namely in palm oil 1, 0.45%, and even in palm oil 2, 0%; in turn, palmitic acid palm oil 1 has 2.88% and palm oil 2 palmitic acid has 24.42%.

English language instruction that moves away from offline to online should become the EFL lecturers’ concern for their students’ successful learning outcome. The students must be kept in the lecturers’ mind when they plan and program the instruction. This study aims at investigating the students’ perceptions and preferences on English instruction through e-learning implementation during the COVID-19 pandemic. This research applies a qualitative approach in a descriptive method design by involving 106 English class students from three different higher educations in Aceh, Indonesia. The thematic and comparative analyses are applied in analyzing the data. The findings of the study show that 50% of the students impress negative features concerning the internet network, a high need of internet quotas, the limitation of learning material explanation and absorption, and the social media influences. The study also reveals that 59.6% of positive features dominate the findings associated with the students’ interest in e-learning implementation as a new learning experience/exploration, engagement and enthusiasm, the flexibility of time and place, and the advance of digital technology usage and adaptation. Besides, WhatsApp, Opensimka, Google Classroom, and Google Meet have become the four most preferable e-learning platform among the respondents. It implies that e-learning implementation during the COVID-19 pandemic gives a variety of practical benefits to university students in the virtual English class. Yet, this still requires sufficient mentoring and extra supporting digital tools for the students and the lecturers.