The potentiality of Pt and MoO3 loading on HBEA zeolite in enhancing n-heptane isomerization was investigated. The multiple characterization techniques revealed the engagement of Pt and MoO3 on the lattice or defect structures of the HBEA framework. Furthermore, the occurrence of dealumination was confirmed by the existence of hydrated aluminium-molybdate, Al2-(MoO4)3. These findings proposed the presence of strong metal-support interactions. The n-heptane isomerization was comparatively investigated over Pt and MoO3 modified catalysts, and significantly higher rate of n-heptane conversion (0.059 ?mol/g-cat m2 s) and rate of iso-heptane formation (0.026 ?mol/g-cat m2 s) were achieved with Pt/MoO3-HBEA catalyst. The catalytic performance followed the order of Pt/MoO3-HBEA > MoO3-HBEA > Pt-HBEA > HBEA. It is anticipated that the results of in-situ FTIR studies of low-temperature hydrogen adsorption and n-heptane adsorption analyses help elucidate the isomerization mechanism and indicated.....

478 hits

Surface modification techniques have been proven to enhance resistance towards corrosion, to slow the process of wearing, to reduce metal ions release, as well as the process of biomaterial osseointegration. Not only that, these techniques could extend the longevity in materials related to implant, primarily because of its response towards the host of body. Generally, these techniques can be further broken down into physical, mechanical, and chemical approaches. As such, this paper presents further information pertaining to the numerous types of methods for modifying surfaces, along with their benefits and drawbacks. Additionally, several other significant aspects are detailed as well in this paper, for example, the materials and biomaterials used for implant, as well as a number of issues concerning the usage of alloy, biomaterial and titanium. ? 2018 Elsevier Inc. All rights reserved...

896 hits

Mobile devices have been utilized as an emerging learning tool in the 21st century to support the learning of chemistry. This study aimed to identify matriculation students? learning experience with regards to the use of mobile devices for learning chemistry. The study employed a qualitative case study approach, which was carried out in a matriculation college. Online diaries and interviews were utilized as the instruments of the study. A total of 84 students initially reflected their learning journey using an online diary, whereas 17 students who were active in mobile learning were purposely selected for the interview. The findings revealed that students have positive and negative experiences towards the use of mobile devices for learning chemistry. They positively perceived that using a mobile device for learning chemistry promotes knowledge construction, visualization of abstract concepts, self-control in learning and intellectual discourse. However, the issue of learning resources .....

1149 hits

Intercalation of 4-amino benzoic acid (4-AB) into Zn/Al-nitrate layered double hydroxide (ZAL2) to form Zn/Al-4AB (ZALAB) compound was successfully synthesized from nitrate salt by using direct co-precipitation method. ZALAB compound was confirmed by Powder X-ray diffraction (PXRD) pattern with a basal spacing of 15.3 �. The presence of COO- and C6H5NH2 functional groups of 4-AB at 1,517 and 1,178 cm?1 in Fourier transform infrared (FTIR) spectrum reinforced 4-AB intercalated into the resulting compound. Based on the thermal analysis, 4-AB in ZALAB compound was more stable compared to pure 4-AB. Breuneur, Emmet and Teller/Barret-Joyner-Halenda (BET/BJH) analyses demonstrated that ZALAB compound is a mesopores-type IV compound with 4.25 m2/g surface area. This material is an irregular shape with different sizes of particles. ZALAB is a potential sunscreen formulation that minimizes the harmful effect on the skin, improving pharmaceutical technology in the skincare treatment. ? 2021, W.....

366 hits

[No abstract available]..

1262 hits

This research develops instructional media in the form of steam-powered boats in STEM learning in elementary schools to support thematic learning in Indonesia. This development aims to help students acquire the skills that match the science and technology of the twenty-first century. The STEM approach is applied so that students can learn and explore various types of integrated interdisciplinary learning. This research aims to: (1) describe the urgency of using the steampowered boat instructional media in STEM learning, (2) develop and describe the final products of the instructional media, and (3) describe the results of the instructional media trials. The research design used was education-based research with the generic model of Educational Design Research (EDR), which involved students and teachers in the trial process. The data collection techniques used were interviews with teachers and students regarding the need for instructional media in STEM learning, observations of the lear.....

1013 hits

The water crisis is identified as the most serious global risk for the coming decade. Distilled water is one of the on-demand elements in academic laboratories; however, water scarcity may eventually affect the education sector, necessitating the implementation of new policies. Human behavior, awareness, knowledge, and opinion is having an impact on water management; accordingly, a questionnaire was purposely designed and validated to assess these variables in a Malaysian public university regarding the use of non-distilled water produced by the distillation process. An exploratory factor analysis yielded four factors: ?concept of green laboratory and water?, ?usage of non-distilled water?, ?knowledge about water distillation?, and ?behavior related to water conservation?. Using the Mann-Whitney U test to compare laboratory and non-laboratory users? responses, the variables ?Knowledge?, ?Behavior?, and ?Opinion? revealed statistically significant differences, with laboratory users scor.....

1025 hits

Er2O3 doped silica borotellurite glasses were synthesized using the melt-quenching technique with a chemical compositional formula (1 ? x){(SiO2)0.2 [(B2O3)0.3 (TeO2)0.7]0.8} (Er2O3)x. Using the XRD, FTIR, UV?Vis, and photoluminescence spectroscopies, the structural, optical and spectroscopic properties of the glasses were studied. The absorption spectra and the refractive index, penetration depth, extinction coefficient, absorption coefficient, dielectric constant, optical conductivity for the glasses were presented. The absorption and emission cross-sections, cross-sectional gain, effective bandwidth, and bandwidth quality factor were also calculated using the UV?Vis data. Photoluminescence and the upconversion luminescence of the glasses were presented for pump wavelengths of 350 nm and 540 nm respectively. The studied glasses presented a high refractive index with values between 2.452 and 2.5153. The emission cross-section, effective bandwidth, bandwidth quality factor increased re.....

515 hits

In this research work, the pattern of spatial cluster had been identified for torrential rainfall data within the context of Peninsular Malaysia, which experiences heavy pour annually. Hence, a robust Principal Component Analysis (PCA) technique was employed in this study in order to address problem related to non-balance cluster(s) across patterns of rainfall stemming from skewed rainfall data. To analyze the observations made, Tukey?s biweight correlation was applied. For PCA components extraction, the optimum breakdown point was determined based on the proposed method. In order to strike a balance for extraction of number of components, as well as to hinder insignificant spatial scale or low-frequency variation, the simulation data recorded a breakdown point at 70% cumulative percentage of variance. The study outcomes revealed that the robust PCA gave better enhancement than the Pearson-based PCA did for cluster average number and quality. The findings indicate that ten rainfall pat.....

406 hits

This article aims to identify the level of spatial noise within the Universiti Pendidikan Sultan Idris Campus. This research is based on an exploratory study using quantitative methods and assisted by a geographic information system (GIS) software. The data used are primary data collected in the field based on sampling at 11 selected locations based on the main road intersection in the Sultan Abdul Jalil Shah Campus (KSAJS). Data collected with the help of the sound meter application in smartphones. Sampling time is from 8 am to 5 pm on weekdays. The analysis used is descriptive analysis and GIS regression technique, which is spatial interpolation to identify areas with the potential to experience high noise levels. The results show that some campus areas experience high noise levels in the morning and afternoon during the rush time going/back to/from work. Noise values ranging from 44.8 dBA to 66.4 dBA were obtained. The value indicates the maximum value exceeds the standard by the De.....

628 hits