https://publisher.uthm.edu.my/ojs/index.php/JST/issue/feed Journal of Science and Technology 2019-02-11T06:00:43+08:00 Ahmad Hadi Ali jst@uthm.edu.my Open Journal Systems <p class="MsoNormal" style="text-align: justify;">The Journal of Science and Technology (JST) is a peer reviewed journal that publishes twice a year&nbsp; (June and December) on articles concerning&nbsp;all areas of science and technology in both theoretical and applied research. JST welcome article submissions from all science and technology research areas including Physics, Chemistry, Biology, Mathematics, Statistics, Biodiversity, Food Science Technology, Engineering Science and Educational Science. JST is intended to provide a forum for the expression of new ideas, as well as a place for exposition of these areas of knowledge&nbsp;that can further understanding of science and technology issues and concerns.</p> https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3673 Preface of Special Issue 2018-12-30T07:52:00+08:00 Editor in Chief of Special Issue jst@uthm.edu.my <span>Editor in Chief of Special Issue</span> 2018-12-30T07:52:00+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3674 Editors of Special Issue 2018-12-30T07:52:00+08:00 Editors of Special Issue jst@uthm.edu.my Editors of Special Issue 2018-12-30T07:52:00+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3645 Effect of Light Intensity on the Total Flavonoid and Total Phenolic Contents of Mikania Micrantha and Tridax Procumbens 2019-02-11T02:32:29+08:00 Aisha Idris hw160077@siswa.uthm.edu.my Alona C. Linatoc alona@uthm.com Surayya Mustapha Muhammad hw160077@siswa.uthm.edu.my Aisha Muhammad Aliyu hw160077@siswa.uthm.edu.my Mohd Fadzelly Abu Bakar fadzelly@uthm.edu.my Flavonoid and phenolics are secondary metabolites produced by plants in response to harsh environmental conditions. Light is one of the most important factor that affects their production. <em>Mikania micrantha</em> and <em>Tridax procumbens</em> are plants belonging to <em>Asteraceae</em> family, and they have bioactivity due to their flavonoid and phenolic contents. The objective of the research is to determine the effect of varying light intensities on the total flavonoid and total phenolic contents of <em>M. micrantha </em>and<em> T. procumbens </em>using three solvents (ethanol, methanol and water). Total flavonoid contents was determined based on the aluminium chloride colorimetry method while total phenolic contents was determined based on the folin-chiocalteau reagent. The results obtained in the study shows that ethanol recovers more flavonoid and phenolic than the other solvents (P &lt; 0.05). Besides, <em>T. procumbens </em>had more flavonoid and phenolic content compared to<em> M. micrantha </em>(P &lt; 0.05)<em>.</em> Nevertheless, the flavonoid and phenolic contents recovered from sun exposed plants was more than that recovered from shaded plants (P &lt; 0.05). This leads to a conclusion that high light intensity can increase the concentration of flavonoid and phenolic of <em>M. micrantha </em>and<em> T. procumbens</em>. 2018-12-30T07:52:00+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3646 Invariance in Transverse Momentum of Photons in Double-slit Experiment 2019-02-11T03:21:23+08:00 Muhammad Amsyar Abdul Rahim maro@ukm.edu.my Mohd Hafizudin Kamal maro@ukm.edu.my Mohd Amir Radhi Othman maro@ukm.edu.my One of the intriguing mystery in modern physics is the quantum interference phenomena, which the behaviour of photons in double-slit experiment is still ambiguous. Instead of relying on the naive probabilistic point of view, Bohmian mechanics provides the ground base for interpreting quantum system in a deterministic way closely related to classical mechanics such as it constructs the photon trajectory for the double-slit set up. The appearance on the bending in the constructed photon trajectory seem to contravene the notable law of conservation of momentum. Here, we report on conservation of the transverse momentum of photon trajectories based on numerical solution of Bohmian mechanics in double-slit set up for single photon, pair of photons and ensemble of photons until interference pattern is produced. It is shown that the total transverse momentum in the system of Bohmian mechanics is invariance due to the non-local action of quantum potential. 2018-12-30T07:52:01+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3648 Compressibility and Permeability of Solidified Dredged Marine Soils (DMS) with the Addition of Cement and/or Waste Granular Materials (WGM) 2019-02-11T03:21:53+08:00 Rosman M. Z. chan@uthm.edu.my Chan C-M. chan@uthm.edu.my Anuar N. M. chan@uthm.edu.my <p>Dredged marine soils that obtained from dredging work were characterize as geo-waste, which is prone to be dumped rather than to be reused. This type of soil is high in compressibility and low in load bearing capacity. The engineering properties of this soft soil can be improve via soil solidification method. Cement is the common hydraulic binder used in soil solidification, were found to generate the emission of greenhouse gasses (GHG), particularly carbon dioxide (CO2) which also had affected the earth’s atmosphere. Therefore, there has been an increasing interest in using alternate pozzolanic materials such as waste granular materials (WGM) to fully or partially substituted the use of cement in soil solidification. WGM such as coal bottom ash (BA) and palm oil clinker (POC) were opted due to its pozzolanic properties. Prior to the planning of reclamation work using DMS admixed with conventional and/or alternate pozzolanic materials, the consolidation characteristics of the admixed materials must be acknowledged. Hence, the present study will examine the amount of settlement and coefficient of permeability (k) of DMS treated with cement and/or WGM in laboratory-scale experiments. Samples were prepared in various proportion in order to examine the individual effect of the cement and/or alternate pozzolanic materials on compressibility and permeability. For cement-admixed DMS, sample with 20 % of cement have significantly reduced the settlement than untreated and 10 % cemented DMS. For WGM-admixed DMS, the initial void ratio is low as compared to the untreated DMS due to the rearrangement of soil particles, which is densely packed. For cement-WGM-admixed DMS, samples of 15C50BA and 15C50POC displayed significant settlement reduction than 10C100BA, 10C100POC and untreated samples.</p> 2018-12-30T07:52:02+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3649 Development of Polyvinyl Alcohol/Chitosan Hydrogel Loaded with Fertilizer Compound: Preparation, Properties and Effect on Seed Germination 2019-02-11T04:15:14+08:00 Nadirul Hasraf Mat Nayan nadirul@uthm.edu.my Mohd Syahir Anwar Hamzah nadirul@uthm.edu.my Abdussalam Al-hakimi Mohd Tahir nadirul@uthm.edu.my Amirah Anis Afina Rajali nadirul@uthm.edu.my Eva Fariska Muslih nadirul@uthm.edu.my Ruzaini Mazlan nadirul@uthm.edu.my This work reports the reinforcement of polyvinyl alcohol (PVA) hydrogel with chitosan as potential superabsorbent (SAP) fertilizer. The PVA/Chitosan hydrogel was prepared using superficial freeze thawing method. Mechanical properties and swelling ratio of the SAP hydrogels were optimum at 6 wt% of chitosan loading. Morphological analysis of the PVA/Chitosan hydrogel revealed excellent crystal like structure distribution and smooth of the surface due to good compatibility between the materials. The water retention of soil containing PVA/Chitosan hydrogel was also examined. It was found that the SAP hydrogel increased the water retention soil and sand at capacity 48.21 and 48.24 % respectively after 15 days. The influence of the SAP hydrogel on seed germination was observed using Okra seeds. The seeding has higher germination energy when the PVA/Chitosan hydrogel incorporated with the soil compared with soil without aid of SAP hydrogel. This is a good indication of the prepared SAP hydrogel for controlled release fertilizer. 2018-12-30T07:52:03+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3653 Creating a GUI Solver for Linear Programming Models in MATLAB 2019-02-11T04:18:25+08:00 Lee Siaw Chong sclee@uthm.edu.my Chin Jia Xin sclee@uthm.edu.my The concept of linear programming (LP) was developed to find out the best solution among all feasible solutions in an optimization problem. This technique becomes much popular and attains great attention from researchers due to its wide application in engineering, computer science, marketing, military and industries. Nowadays, there are many commercial software that apply this technique to solve optimization problems, e.g. Excel Solver, TORA, AMPL, LINGO and MATLAB. In this paper, we aim to use MATLAB to develop a Graphical User Interface (GUI) solver for LPs, namely LpSolver. The LP methods that will be included in our solver are the simplex method, the Big-M method, the Two-Phase method and the Dual-Simplex method. We try to make our solver perform calculations in symbolic form so that the result will be free from rounding errors. Besides that, we added a few features such as creating animated 2-D graphs and generating a detailed tableau showing all intermediate iterative results; in which the user can use it to trace the convergence path that leads to the optimal solution. In the later part of this paper we test our solver with a simple classroom sized problem. 2018-12-30T07:52:04+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3654 The Influence of Nonlinearity Properties in Generating Octave-spanning Light 2019-02-11T04:30:37+08:00 Mofaq M.B. Alsaady norazura@uthm.edu.my N.A. Awang norazura@uthm.edu.my Z. Zakaria zahariah@uthm.edu.my <p>An efficient system for nonlinear parameter characterization in Highly Nonlinear Fiber (HNLF) is described using four wave mixing (FWM) technique, the FWM plays an important role in enhancing the spectrum development in most cases. The Nonlinear parameters like zero-dispersion wavelength (ZDW), chromatic dispersion (CD) and the non-linear coefficient of HNLF were successfully investigated using this technique. The results of this technique have been almost identical to factory specifications. By FWM technique, a CD at 1550 nm slope is obtained from 0.007 ps.nm-2km-1, ZDW of 1531 nm and nonlinear parameters of 10.7 W-1km-1.</p> 2018-12-30T07:52:05+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3655 Vertical Aerated Recycled Concrete Aggregate Filter for Removal of Phosphorus 2019-02-11T04:31:11+08:00 Suraya Hani Adnan suraya@uthm.edu.my Norwardatun Abd Roni suraya@uthm.edu.my This paper assesses a new design of recycled concrete aggregates as vertical aerated filter for removal of phosphorus (P). Recycled concrete aggregates (RCA) obtained from crushed concrete waste. In this study, RCA is used as an Aerated Filter for removal of P. A commercial concrete was crushed, and the RCA were sieving according to different sieve size. The highest percentage passing sieve size is size 5 mm to 10 mm is 99.54%. The pH value for RCA is 9.30 which is alkaline. RCA with smallest size and lowest initial concentration of P which is 5mm to 10 mm and 10 mg/L respectively has the lowest uptake capacity which 0.995 mgL-1/g. Moreover, the RCA also contain Phosphorus (P) element which is that it proven for us that RCA has a high capacity for absorbing phosphorus. After a few months in the aerated filter system, phosphorus can be seen on the surface of RCA samples after being examined by EDX test. The usage of RCA will ease the environmental problems that are currently perceived globally. RCA could also saves landfill space which helps reduce the needs for gravel mining and reduces pollution. 2018-12-30T07:52:05+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3660 Properties of Cement Brick Containing Expanded Polystyrene Beads (EPS) And Palm Oil Fuel Ash (POFA) 2019-02-11T05:08:46+08:00 N.A. Kamarulzaman suraya@uthm.edu.my S.H. Adnan suraya@uthm.edu.my K.A. Mohd Sari suraya@uthm.edu.my M.H. Osman suraya@uthm.edu.my M.L. Ahmad Jeni suraya@uthm.edu.my M.S. Abdullah suraya@uthm.edu.my P. Ang Soon Ern suraya@uthm.edu.my N.F. Yahya suraya@uthm.edu.my N.I.M Yassin suraya@uthm.edu.my M.N.A. Wahee Anuar suraya@uthm.edu.my <p>This paper assesses the mechanical properties of cement brick containing Expanded Polystyrene Beads (EPS) and Palm Oil Fuel Ash (POFA) as partial replacement of sand and Ordinary Portland Cement (OPC). The aim of this research are to determine the mechanical properties of brick containing EPS and POFA as partial replacement of sand and OPC. The dosage for EPS replacement is 20%, 30%, 40% and 50% EPS whereas 5%, 10%, 15%, 20% and 25% of POFA replacement. The mechanical properties of the bricks are density, compressive strength and water absorption. The bricks with 30%, 40% and 50% EPS replacement have density below 1680 kg/m<sup>3</sup> which considered as lightweight brick. The brick with 50% EPS replacement recorded lowest density which is 1328 kg/m<sup>3</sup> while 1629 kg/m<sup>3</sup> for the brick with 25% POFA replacement at 56-days of curing. The water absorption testing for these brick are between 7.20%-18.19%. Brick with 0% POFA and 50% EPS replacement has the lowest water absorption properties whereas brick with 25% POFA and 0% EPS replacement has the highest water absorption properties.</p> 2018-12-30T07:52:06+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3661 Influence of Light Intensity on the Photosynthesis and Phenolic Contents of Mangifera Indica 2019-02-11T05:09:24+08:00 Alona C. Linatoc alona@uthm.edu.my Aisha Idris hw160077@siswa.uthm.edu.my Mohd Fadzelly Abu Bakar fadzelly@uthm.edu.my Light is an important environmental factor that have an influence on a plants photosynthesis and production of secondary metabolites like phenolic compounds and flavonoid. <em>Mangifera indica</em> from the family <em>Anacardiaceae</em> is known to have bioactivity due to its phenolic and flavonoid contents. The objective of the study is to determine the influence of light on the photosynthesis and phenolic contents of <em>M. indica</em>. Photosynthesis of the plant was measured using a portable photosynthesis system referred to as LICOR- 6400. Photosynthetic pigments as well as phenolic and flavonoid contents were quantified using a UV-VIS spectrophotometer. The outcome derived from the study shows that sun exposed leaves of the studied plant were having the maximum photosynthesis, saturation and compensation points (P &lt; 0.05). Moreover, sun exposed leaves were having higher carotenoid, phenolic and flavonoid contents but lower chlorophyll contents. This leads to a conclusion that sun leaves of <em>M. indica</em> contribute the highest photosynthesis and phenolic contents to the plant. 2018-12-30T07:52:06+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3662 Sound Absorption of Palm Coir Fiber 2019-02-11T05:59:46+08:00 Rahmad R. rohani@uthm.edu.my Ahmad Sukri A.S. ahadi@uthm.edu.my This research was conducted to study acoustic characteristic of palm coir fibre, which has high potential to be use for sound absorbing material. The sample was tested with different weight ratio. The weight ratio of palm coir fibre varied from 30 gm to 60 gm with 20 mm thickness. The samples were deformed by using the mould that was invented by using PVC pipe. These sample were tested by using Impedance tube according to international standard, ASTM E1050-98 used for measuring the sound coefficients. While for density and porosity test, the sample was tested according to international standard ASTM D792. The results showed sound absorption coefficients of palm coir fibre were good from 350 Hz to 2000 Hz within the range 0.65 dB – 0.90 dB for Impedance tube. Results obtained for density and porosity test, also were good from 30gm and 60gm respectively. Overall, the optimum, sound absorption coefficient was obtained from weight 40gm. These results indicate that palm coir fibre is promising to use as raw material of sound absorbing material with low cost, light and biodegradable. 2018-12-30T07:52:07+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3663 Study of Apple Packaging Material Properties by Using Parchment and Recycled Paper 2019-02-11T06:00:16+08:00 Rahmad R. rohani@uthm.edu.my Abdul Rahman Z.A.R rohani@uthm.edu.my This paper investigated the potential properties of apple packaging material used as a major ingredient for promoting eco-friendly apple packaging materials. In addition, old newspapers and parchment paper were used as specimens to assess natural behavior of the apple packaging material. The main objective was to determine the mechanical properties of the paper with different amount or the different percentage of parchment paper and recycled paper compositions. The response of this study was identifying the tensile strength, bursting strength and tearing strength factor. The results showed production of papers from parchment paper and recycled paper affects the strength of the paper itself. The increase in the percentage of recycled paper has resulted in the mechanical properties of ascending paper. The combination of 60% recycled paper and 26% parchment paper produces the best mechanical properties with tear strength of 25.1 N. Meanwhile the composition of 43% parchment paper, 43% recycle paper and 14% of potato flour resulted with 856.0 kPa burst strength and 224.0 N tensile strength. The conclusion suggests that the combination of recycled paper and parchment paper can be one of the alternative raw materials used to package an apple. 2018-12-30T07:52:07+08:00 Copyright (c) 2018 Journal of Science and Technology https://publisher.uthm.edu.my/ojs/index.php/JST/article/view/3671 Influence of Deposition Parameter to Wear Behaviour of Tungsten Carbide-Nickel (WC-Ni) High Velocity Oxyfuel (HVOF) Coating 2019-02-11T06:00:43+08:00 Mohd Affifudin Abdul Patar zakiah@uthm.edu.my Z. Kamdi zakiah@uthm.edu.my This study is done to investigate the influence of deposition parameter to the hardness and wear<strong> </strong>resistance of the tungsten carbide nickel (WC-Ni) High velocity oxy-fuel (HVOF) coating which is sprayed on the AISI 1040 medium carbon steel. Three different spraying parameters were used with the oxygen flowrate of each being changed and all other parameters and its value is kept constant. Oxygen flowrate of 30, 45 and 60 LPM were used. The result of hardness, wear rate and surface morphology were compared between the coatings. To compare the surface morphology of the three different parameter HVOF coatings, a scanning electron microscope was used. No significant changes shown on the surface of the coatings where all shows the same lump and crevices structure. X-ray diffraction was used to observe the elemental composition on the three coatings, all the coatings have the same elements present on them. It can be seen that all the coatings contains nickel, tungsten carbide, tungsten (II) carbide and oxygen. The method used for hardness test was the Vickers microhardness tester while weight loss test was used to study the wear resistance. Following the test, it is found that the hardness and wear resistance increased as the oxygen flowrate was increased. The highest hardness and wear resistance can be found in the coating with 60 LPM oxygen flowrate. 2018-12-30T07:52:07+08:00 Copyright (c) 2018 Journal of Science and Technology