Al doped ZnO (ZnO:Al) thin films was grown on corning glass substrate using dc magnetron sputtering. ZnO:Al thin film grown with plasma power 40 watt and 500 mTorr argon pressure for 120 minutes. Film was grown annealed on oxygen atmosphere with different pressure for 20 minutes. The crystalline of ZnO:Al film deposited has an hexagonal structure. The crystallites preferred orientation shift gradually from (002) to (101) direction as the pressure of oxygen increases. Transmittance in the visible regions increases with increasing pressure of oxygen about 81,27%. The optical characterization indicated that the band gap shift toward lower energies with increasing pressure of oxygen...

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Multiwall carbon nanotubes (MWCNTs) ability to improve electrical, optical and mechanical properties of nanocomposites, have attracted great amount of interest for their huge potential in applying them as filler in polymer matrix. However, this application was hindered because of their low dispersion in polymer matrix and tendency to self-associate into macro-scale aggregates. Recently, diffusion of MWCNTs in cellulose polymer matrix was studied and prepared via latex technology approaches by the addition of 1-butyl-3-methyl-imidazolium (BMIM)-surfactant. The performance of BMIM-surfactants for dispersing MWCNTs in polymer was characterized using a range of techniques including field emission scanning electron microscopy (FESEM), and Thermogravimetric analysis (TGA). Meanwhile, the conductivities of the nanocomposites were also investigated using four-point probe measurements. In this study, MWCNTs were efficiently dispersed in cellulose utilizing 1- butyl-3-methyl imidazolium-dodecyl .....

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Habits of mind (HOM) is one of the kind response to those questions and problems whereby the answers to which are not immediately known which can attribute to effective problem solvers and critical thinking development. However, the emphasis on this aspect is still low especially among science educators as well as secondary science students which in the long run will retard the production of knowledge worker who are able to behave when confronted with life’s problems. The study addressed the integration of Thinking Based Learning (TBL) and the 6E Instructional Model as a teaching approach in nurturing habits of mind among secondary students while doing their Science, Technology, Engineering and Mathematics (STEM) project. The study involved 30 students from a Lower Secondary School in a sub urban school in Kota Bharu, Kelantan. Students were given a STEM Raft Module integrating TBL and 6E Instructional Model for five weeks to come out with a model of a raft based on science concepts .....

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The innovation in this instruction was the use of medicine card as a learning media of periodic table of elements. This research aimed to know the process of learning conducted by using medicine card and to know the students' motivation and learning outcomes as the result of the implementation of medicine card in the classroom activity. This research used a quantitative descriptive method. The implementation of the media was conducted in fourfold meetings in Health Vocational School of Sadewa, Yogyakarta, Indonesia. A SWOT analysis was conducted at the beginning of the learning innovation and was followed by the observation and the preparation of material and media. The class activity began with explanations of medicine card games, group divisions, game execution, and confirmation. The final step was evaluated using a questionnaire of motivation and post-test problems. The result of the questionnaire indicated that the students’ motivation was in the good criterion and the learning o.....

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Ficus deltoidea Jack or locally known as mas cotek from the family of Moraceae has been acknowledged for its occurrence of several varieties based on the variations of leaf morphology, namely F. deltoidea var. angustifolia (Miq.) Corner, F. deltoidea var. bilobata Corner, F. deltoidea var. kunstleri (King) Corner, F. deltoidea var. lutescens (Desf.) Corner, F. deltoidea var. trengganuensis Corner, F. deltoidea var. motleyana and F. deltoidea var. deltoidea Jack. In this work, we report on the chemical profiles using chromatographic techniques on the seven varieties of F. deltoidea by analysing the presence of the bioactive compounds, vitexin and isovitexin and characterising the other major peaks in the chromatograms. Observation on the HPLC chromatogram showed the presence of both compounds in all samples except FDv. K (vitexin only) and FDv. I. Other peaks showed a characteristic of flavonoids based on the UV spectra pattern with UV maxima at 270 and 338 nm except for peaks 6, 7 and .....

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To investigate the feasibility of using isolated knee performance to measure the f-v profile of human muscle in vivo, we were using isokinetic dynamometry (IKD) technique that span the entire f-v profile of skeletal muscle. With institutional ethics approval, eleven healthy males (mean ± SD: age, 24.9 ± 3.1 years; body mass, 80.2 ± 10.1 kg; height, 176.2 ± 7.1 cm) completed this study. The participants were physically active and were familiarized with the techniques and protocol prior to completing 4 experimental sessions (1 introductory session and 3 repeated experiment sessions). The sessions was used a protocol of knee extensor function on IKD at isometric mode and angular velocities of 60˚.s-1, 120˚.s-1, 240˚.s-1 and 450˚.s-1. IKD data were not significantly different across the 3 repeated trials, demonstrating there was no evidence of systematic bias. The average coefficient of variation (CV) of IKD was 9.3 ± 3.0% ranging from 7.0 to 15.7%. Therefore the isolated knee per.....

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River pollution impact human health, environment and the sustainable development. This study was conducted to identify spatial patterns and the main parameters affecting the water pollution within nine monitoring stations in the Muda River basin (Malaysia) over a 16-year database (1998–2013). Environmetric techniques were applied to the dataset. These combined Cluster Analysis, Discriminant Analysis, and Multiple Linear Regression. The Cluster Analysis showed that the monitoring stations divided into two separate groups based on similarities features of water quality while Discriminant Analysis validated these groups. Furthermore, the Multiple Linear Regression analysis showed that the significant parameters contributing to variability the Water Quality Index was biological oxygen demand, chemical oxygen demand and ammonia nitrogen. This was due to the point-source pollution, particularly from rubber factory. Therefore, the results provided information to support future water polluti.....

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This research was conducted to develop the multimedia of colloidal systems as an enrichment media for vocational high school students in chemistry class and to know the quality of the multimedia. This was a research and development study. Developmental procedures used in this research were adopted from Borg and Gall development procedures consisting of six phases including: collecting information, planning, developing the preliminary form of the product, validating and revising the product, assessing the product, and revising final product. The products were validated by one content expert and one media expert and reviewed by three peer reviewers. The advises from the experts and the peer reviewers were used to improve the initial product. The assessment of the product was carried out by five reviewers based on six aspects of the criteria, included: content feasibility, language, visual-display of media, audiodisplay of media, media programming, and expediency of the media. The product.....

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This research was conducted to explore how procedural knowledge of bilingual students in chemical equilibrium problem-solving skills. This research was a descriptive study of 31 bilingual private high school students. Chemical equilibrium problem solving skills were collected by three problems, while the procedural knowledge was collected by analysis of student answers, self-assessment metacognition questionnaire, and the interview with students and their chemistry teacher. Data collected was analyzed by a phenomenological reduction method. The results of students’ procedural knowledge were categorized into assumption determination (54,84%), strategy development (22,58%), chemical equation (41,94%), factors affecting the equation (61,29%), using the other knowledge (29,03%), quantitative analysis (38,71%), and alternative strategy (25,81%). According to the operator in each framework answer, the result of students’ answers of chemical equilibrium problem-solving skills was classifi.....

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A study was performed to investigate the volatile constituents of three conifer species (Podocarpus neriifolius, Nageia motleyi and Dacrydium elatum) which were planted in the main campus of Forest Research Institute Malaysia (FRIM). The fresh leaves were extracted by Clavenger hydrodistillation apparatus and the essential oils were analysed by GC and GC/MS analysis. Analyses revealed that the P. neriifolius and N. motleyi oils were rich with sesquiterpenes and have monoterpenes in very trace amount. The major sesquiterpenes of P. neriifolius oil were phyllocladene (26.37%), kaurene (13.75%), bicyclogermacrene (12.14%) and followed by sandaracopimara-8(14), 15-diene (7.89%) and βcaryophyllene (6.25%). Meanwhile, the major components of N. motleyi oil were bicyclogermacrene (45.85%), viridiflorene (12.36%), globulol (9.48%) and germacrene D (6.15%). D. elatum oil has mono- and sesquiterpenes as its main components in which β-caryophyllene (29.03%), α-pinene (28.41%), phyllocladene (2.....

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