bluuebunny/crossref_metadata_2025 huggingface dataset:
Pre-clinical test of dental leucite glass-ceramics from local high grade silica sand: an in vitro study (cytotoxicity and genotoxicity)
Authors: Saiyed Mohd Nurddin Siti Mazatul Azwa , Selamat Malek
Published: October 2017

The need for biocompatible  of dental materials for use in restorative dentistry has generated a requirement for cytotoxicity and mutagenicity assays to screen compounds and characterize the potentially harmful effects of a material to oral tissues prior to clinical use.  The objective of the study was to determine the degree of biocompatibility of leusite glass-ceramics that have been produced from local high grade silica sand in terms of cytotoxicity and mutagenicity assays.  In the present study,   the cyctotoxicity and mutagenicity were studied using the MTT and Ames Reverse Mutation.  In the MTT assay, a dose response cytotoxicity of leucite sample was evaluated in L929 cells.  The cells were treated with the concentrations of 6.25, 12.5, 25.0, 50.00, 100.00 and 200.00 mg/ml of the leucite sample for 24 hours.  The cytotoxicity was determined by assessing the cell viability through the reduction of tetrazolium salts (MTT).  The mutagenenicity of leucite sample was evaluated in S. typhirium TA98. TA100, TA1535, TA1537 and E. coli WP2 in the Ames Reverse Mutation assay.  Mutagenic effects were evaluated by comparing the mean number of revertant colonies of each extract concentraction with mean number of revertant colonies of the negative control.  In results of MTT assay evaluated that the leucite did not show a cytotoxic effect at all concentrations under the condition of the study.  Ames Reverse Mutation assay result proven that the leucite sample did not demonstrate a mutagenic effect under the condition of this study with Salmonella typhimurium and Escherichia coli.
Generalization of the graph of fuzzy topographic topological mapping
Authors: Sayed Mohamed , Ahmad Tahir
Published: October 2017

In 1999, Tahir et. al. developed the Fuzzy Topographic Topological Mapping to determine the location of epileptic foci in epilepsy disorder patients.  The model which consists of topological and fuzzy structure is composed into three mathematical algorithms.  There are two FTTMs up to now, namely FTTM version 1 and FTTM version 2.   FTTM version 1 is homeomorphic to FTTM version 2.  The homeomorphism of FTTM can be presented using graphs.  In this paper, we generalized  the graph of FTTM. In other words, we will prove that, if there exist k versions of FTTM, the new elements will produce a graph of degree 8k3+8k-24.
Photocatalytic decolorization of methylene blue using zinc oxide supported on mesoporous silica nanoparticles
Authors: Abdul Rahman Anis Farhana , Sy Mei Ling , Abdul Jalil Aishah , Triwahyono Sugeng
Published: October 2017

Various dyes that are used in textile, paper, cosmetics and plastics industries may produce harmful effects on the health of living organisms and the environment if not treated properly before being discharged into water bodies. Among many techniques, photocatalytic process is one of the promising treatment for these dyes. Zinc oxide (ZnO) is well-known comparable with TiO2 due to its unique properties and numerous advantages. While, mesoporous silica nanoparticles (MSN) is an excellent solid support for heterogeneous catalysts due to its high surface area, thermal and mechanical stability, highly uniform pore distribution, tunable pore size, and unique hosting properties. Therefore, in this study, ZnO/MSN (ZM) catalysts were prepared and its physicochemical properties was characterized by X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The catalyst was tested on the photodecolorization of methylene blue (MB) dye. The results showed that the interaction between ZnO and MSN support could enhanced the photocatalytic activity. The 0.5 g L-1 of 5ZM was found to give the highest degradation (80 %) of 10 mg L-1 of MB solution at pH 7 after 3 h under UV light irradiation. The photodecolorization followed the pseudo first-order Langmuir-Hinshelwood kinetic model. This study demonstrated that the prepared 5ZM has a potential to be used in photocatalytic degradation of various dyes as well as organic pollutants.
The synthesis of cuprous oxide nanowires in the presence of oxygen using a hot tube thermal evaporation method
Authors: Khan Muhammad Arif , Sakrani Samsudi , Wahab Yussof , Suhaimi Syahida , Muhammad Rosnita
Published: October 2017

Cuprous oxide nanowires have been synthesized by heating copper foil in the presence of oxygen rich environment using a hot tube vacuum thermal evaporation method.  The effect of growth parameters such as growth time, temperature and oxidative environment on the morphology of the nanowires is investigated. The growth of cuprous oxide nanowires from copper foils thermally oxidized in the presence of oxygen rich at temperatures between 300 and 500 0C. The nanowires were formed within the temperature range of 400 – 500 0C with diameters and length between 25 - 100 nm and length 1 - 4 µm, respectively.  This gave an estimate of  aspect ratio around 40. Observation from FESEM results revealed the optimal growth of cuprous oxide nanowires which occurred at oxidation times for 1h, 1/2h and 25 minutes and flow rates of oxygen at 0.09 psi, 0.12 psi and 0.08 psi. The atom% of copper and oxygen were measured using EDX and their existence were later confirmed by XRD, essentially indicated by 40% an 60% of copper  and oxygen contents, respectively.
Total phenolic content and antioxidant activity of pure and formulated extracts of kesum (polygonum minus), bawang putih (allivium sativum), pegaga (centella asiatica), and ulam raja (cosmos caudatus)
Authors: Zakaria Nooraini , Baba Sayang , Ku Bahaudin Ku Nurul Aqmar , Hamdana Salehhuddin
Published: October 2017

The use of herbs, spices, vegetables and medicinal plants have been traditionally utilize as the alternate medicinal to treat many of diseases by virtue of their antioxidant actions. Kesum, bawang putih, pegaga and ulam raja were extracted by using juice extractor without additional of solvent. The pure extracts were determined for moisture content and the pure and formulation extracts were analyzed for total phenolic content (TPC) and antioxidant activity (DPPH radical scavenging assay). The yield showed that kesum, bawang putih, pegaga and ulam raja extraction yield at 8.5%, 12%, 22.5% and 24% respectively. The results showed that, there was significant difference (P < 0.05) in total phenolic content and antioxidant activity between pure and formulation extracts. Formulated kesum and bawang putih (1:0:0:1) extract had the highest total phenolic content (1703.59 ± 11 GAE/100mg) followed by kesum pure extract (1388.19 ± 11 GAE/100mg) and bawang putih pure extract (1177.87 ± 138.82 GAE/100mg).  No significant was noted and positive Pearson’s correlations between TPC and DPPH assay (r = 0.293) was observed for all plants extract. The statistical indicated that phenolic compounds were not the main contributor of antioxidant activity in plants. Further, there was no synergistic effect observed for pure and formulation extracts.
Vehicle routing problem with time constraints
Authors: Johar Farhana , Potts Chris , Bennell Julia
Published: October 2017

This paper addresses the Vehicle Routing Problem (VRP) with time constraints which been solved by several heuristic algorithms. The problem starting at the depot where the customer orders which associated with due date determined by customer, are released with different point of time. Ideally, to avoid any lateness in delivery process, the orders need to be delivered as soon as it released and available at the depot. However, this may increase the traveling cost because one vehicle needs to go and come back to depot for the other deliveries which this can be saved by batching the deliveries. Therefore, the study will focus on minimizing the tradeoff between traveling and tardiness costs.  Literatures show that implementing the heuristic algorithms for solving various instances of VRPs manage to minimize the distribution cost within the reasonable computing times. An initial feasible solution was generated using a constructive heuristic. The solution then was improved by several metaheuristic algorithms were developed for solving the problem studied; Variable Neighborhood Search, Large Neighborhood Search and Tabu Search. To cater with the problem studied, a modification to the benchmark problems of Solomon has been done. The performance of the algorithms can be seen through the comparison of the solution obtained.  The results showed that there is a significant saving in producing the least cost solution and manually constructed routes are very ineffective.
Water tree in polymeric cables: a review
Authors: Sanniyati Che Nuru , Z. Arief Yanuar , Adzis Zuraimy , Muhamad Nor Asiah , Ahmad Mohd. Hafizi , Sidik Muhammad Abu Bakar , Lau K. Y.
Published: October 2017

The power cable breakdown suspected due to water treeing in polymeric cables are said to be the main cause. The inconsistent and unreliable nature brings out the importance of research in water treeing detection in polymeric cables. Early detection of water tree in polymeric cables is important in order to increase the cable efficiency by reducing the timeframe of the cable failure. This paper presents a comprehensive review of water treeing detections in polymeric cables, in particular, the relation to the background of water treeing, the types of water treeing, experimental investigations on water treeing, and factors affecting the initiation and growth of water trees.
The significant factors for the people with epilepsy high employability based on multiple intelligence scores
Authors: Awang Siti Rahmah , Alimin Nur Sofia Nabila
Published: October 2017

The objective of this study is to develop an employability model which involves significant factors that lead to high employability for People with Epilepsy (PWE). The sample used in this study consists of outpatients at the Neurology Department Hospital Kuala Lumpur (HKL) and Hospital Sultanah Aminah (HSA), Johor Bahru. The sample size from HKL are 148 patients and from HSA are 67 patients that made up a total sample of 215 patients. The main method used in this study is binary logistic regression analysis in order to build the model and to determine the significant employability factors. Several model fit tests like Classification Table, Omnibus Tests of Model Coefficients, Likelihood-Ratio Test, Hosmer and Lemeshow Test and Cox and Snell R2 & Nagelkerke R2 are discussed in this paper. From the employability model built, eleven significant factors are obtained which increase the chances for the PWE to be employed namely gender, marital status, education background, age of the respondents, onset age, musical intelligence, kinesthetic intelligence, logic/math intelligence, spatial intelligence, intrapersonal intelligence and naturalistic intelligence.
Structural, magnetic properties and microwave absorbing behavior of iron based carbon nanocomposites
Authors: Sunandar Mashadi
Published: October 2017

Nanocomposite of α-Fe/C was successfully synthesized by mechanical milling method. Analytical-grade of α-Fe and graphite powders with a purity of greater than 99% were mixed. The mixture was milled for 50 hours at room temperature using High Energy Milling (HEM). The refinement results of X-ray diffraction pattern shows that the α-Fe/C nanocomposite consists of 20 wt% Fe and 80 wt% C. The mechanical milling resulted in α-Fe/C powders with mean particle size ~900 nm. The image reveals the morphology of particle and the particles that exist is aggregates of fine grains. The magnetic properties of the particle α-Fe/C nanocomposite showed low coercivity and high remanent magnetization. The α-Fe/C nanocomposite has certain microwave absorber properties in the frequency range of 9 – 15 GHz, with the maximum reflection loss reaches -10 dB at 12 GHz and the absorption range under −4 dB is from 11.2 to 15.5 GHz with 2 mm thickness. The study concluded that the α-Fe/C nanocomposite shows good candidate materials for microwave absorbing materials applications.
Flow and heat transfer in MHD visco-elastic fluid with ohmic heating
Authors: Das Bandita , Choudhury Rita
Published: October 2017

An investigation is made of the motion of a visco-elastic, MHD free convective flow and mass transfer past an infinite vertical plate. The effects of ohmic heating and viscous dissipation are taken into account. For solving the non-dimensional governing equations of motion perturbation technique has been into used and the important properties of the overall structure of the fluid motion are studied. The effect of various parameters of the velocity field, concentration field and temperature distribution are discussed with the help of graphical illustration.
Amylase from bacillus thuringiensis isolated from tapioca waste: isolation, partial purification and characterization
Authors: Zusfahair Zusfahair , Ningsih Dian Riana , Kartika Dwi , Fatoni Amin
Published: October 2017

Microorganism enzymes are the most widely used in industrial applications. Tapioca liquid waste could be a great source of amylase-producing bacteria. The aim of this research was to isolate the amylase-producing bacteria form the tapioca waste, to produce amylase and to purify the resulted amylase. The screening, identification, and the optimal production condition of the amylase‒producing bacteria were studied.  The optimization of bacteria production growth phase and the amylase production time were investigated. The crude amylase was purified using ammonium sulfate fractionation followed by SDS PAGE electrophoresis to identify the molecular weight and to purity of the amylase. The amylase activity assay used was based on the measuring of resulted reducing sugar by Somogyi-Nelson method. The result showed that the amylase producing bacteria was identified as Bacillus thuringiensis. The exponential phase of the bacteria growth for bacteria adaptation before production was 18 h and the optimal production time of amylase enzyme was 24 h. The highest specific activity of the purified amylase was fraction (FHD) 40% with specific activity of 37.56 ± 0.38U/mg. The SDS PAGE of FHD 40% profile showed two clear bands with molecular weight of 32 kDa and 35 kDa respectively
Vanadium oxides doped porous titania photocatalysts for phenol photodegradation
Authors: Lee Siew Ling , Khaw Swee Por , Ooi Yee Khai
Published: October 2017

Vanadium oxides (1 - 5 wt%) doped porous TiO2 using tetrabutyltitanate and cetyltrimethyl ammonium bromide as Ti precursor and template, respectively was successfully synthesized via sol-gel method. All the samples crystallined in anatase phase as indicated by X-ray diffraction analysis. The results of diffused reflectance UV-visible spectroscopy analysis showed that the band gap energy of TiO2 reduced from 3.02 to 2.72 eV after introduction of 5 wt% V. The nitrogen adsorption-desorption analysis revealed that the surface area of samples increased with the amount of V dopant. These materials contained of disorder mesopores with particle size ranged 5 – 56 nm. Amongst, sample 4V-TBT-p-TiO2 recorded the highest percentage of phenol degradation (62.2%) under visible light irradiation
Tungsten-oxide modified silica-titania oxidative-acidic bifunctional catalyst for diol synthesis
Authors: Lee Siew Ling , Lim Swee Ean , Che Me Salasiah
Published: October 2017

Oxidative-acidic bifunctional catalysts of tungsten oxide modified silica-titania,xW/TiO2-SiO2 (x=1, 5, 10 wt%) were successfully synthesized and characterized. Both XRD and UV-Vis analyses results indicated presence of WO3 phase in samples with higher dopant amount.  It also revealed tetrahedral Ti and octahedral coordinated existed as the dominant species in the samples.  FTIR analysis suggested formation of Si-O-W in the tungsten oxide modified samples. The catalytic performance of the samples was evaluated via consecutive transformation of 1-octene to 1,2-octanediol through the conversion of 1,2-epoxyoctane using aqueous H2O2 as oxidant. While TiO2-SiO2 and 1W/TiO2-SiO2 showed no catalytic activity in yielding diol, samples 5W/TiO2-SiO2 and 10W/TiO2-SiO2 exhibited bifunctional catalytic activity. It has been demonstrated that sample 10W/TiO2-SiO2 was the best oxidative-acidic bifuntional catalyst which produced 321 μmol 1,2-epoxyoctane and 51 μmol 1,2-octanediol after 24 h reaction.
Immobilization of lipase onto mesoporous silica KIT-6 and montmorillonite K10 for enzymatic hydrolysis of tributyrin
Authors: Golbaha Noorulsyahidaini , Ramli Zainab , Endud Salasiah
Published: October 2017

Mesoporous silica KIT-6 and montmorillonite (MMT) K-10 clay were prepared and used for immobilization of the enzyme, Candida rugosa lipases (CRL), aiming at their use as biocatalysts for the hydrolysis of tributyrin. Immobilization of the enzymes onto the supports was performed by physical adsorption using 0.1 M phosphate buffer solutions (pH 7) as the dispersion medium. The activity of the immobilized CRL for tributyrin hydrolysis was investigated at incubation temperature of 40 °C during 120 min and different concentration of the lipase solution for both the supports. Characterization by XRD showed that the long-ranged ordering in the KIT-6 and crystallinity of the MMT K-10 material were affected slightly by the lipase immobilization. This result gives an indication to the present of lipase-support interaction in the immobilized lipase system. Additionally, the results of FTIR spectroscopy verified the presence of silanols on the surfaces of MMT K-10 and KIT-6 materials, while the nitrogen adsorption data showed the resulting immobilized enzyme catalysts were rendered porous, with the KIT-6 giving higher specific surface areas and higher pore diameters in a narrow distribution of sizes ranging from 4 to 12 nm. The immobilization of CRL on KIT-6 and MMT K-10 through hydrogen bonding with the silanol groups, led to an increase in the hydrolysis activity compared to that of free lipase. However, the activity of KIT-6 immobilized CRL was higher than was observed on MMT K-10 immobilized CRL. Furthermore, lipase immobilized on mesoporous silica KIT-6 was shown to be recyclable up to 5 times in aqueous medium. The high surface area and the unique pore system of the mesoporous silica KIT-6, having may be the crucial factors that play an important role in retaining the enzyme in the support, and consequently, improving the lipase activity and stability.
A review of leakage current mechanism in nitride based light emitting diode
Authors: Hedzir Anati Syahirah , Muridan Norasmahan , Hasbullah Nurul Fadzlin
Published: October 2017

We review the dominant mechanism and characteristics of it which gave rise to the existence of forward and reverse leakage current in nitride based light emitting diode (LED). LED is one of the promising device to be used as a lighting source because it does not contain mercury unlike fluorescent lamps. However, the existence of leakage current can affect the reliability and efficiency of LED. Hence, its importance to understand the mechanism that responsible for its existence. The occurrence of leakage current is divided into three main parameters: 1) low bias; 2) medium or high bias; 3) temperature dependence. In low reverse bias, Poole-Frenkel is the dominant mechanism while tunneling is the dominant mechanism in high bias region. Furthermore, in forward bias, defect assisted tunneling is most likely the dominant mechanism. In low forward bias, electrons are the dominant carriers in defect assisted tunneling while in medium forward bias, holes are the dominant carriers.  Moreover, Variable Range Hopping (VRH) is reported to be dominant when the temperature of conduction is below 200K.
Fuzzy autocatalytic set (FACS) as fuzzy vector space
Authors: Edhelyn Rossiana , Ahmad Tahir
Published: October 2017

Dynamic model of clinical waste incineration process in Malacca has been successfully developed using Fuzzy Autocatalytic Set (FACS) of Fuzzy Graph Type 3. FACS combines the concept of fuzzy graph and autocatalytic set and has been proven to yield more precise results than using crisp graph. Next, the graph of its process has been transformed from non-coordinated FACS to coordinated FACS in Euclidean space. Some mathematical structures related to the transformation are adjacency, transition and Laplacian matrices of FACS. Furthermore, it is found that FACS to be primitive, irreducible and aperiodic. The set of adjacency matrices of FACS of Fuzzy Graph Type 3 is predicted to be seen as fuzzy vector space, and the set of Euclidean distance matrices represent coordinated FACS is also expected to be fuzzy vector space as well. As a recently developed theory, FACS has great capabilities in generating new mathematical theories and structures that would enrich the theory itself. this study is made to attempt the formulation of new algebraic structure in FACS which is fuzzy vector space.
Radiation effect on unsteady MHD flow through porous medium past an oscillating inclined plate with variable temperature and mass diffusion in the presence of hall current
Authors: Rajput U. S. , Kumar Gaurav
Published: October 2017

In the present paper, we study the effect of radiation on unsteady flow of a viscous, incompressible and electrically conducting fluid past an oscillating inclined plate through a porous medium with variable wall temperature and mass diffusion in the presence of transversely applied uniform magnetic field. The plate temperature and the concentration level near the plate increase linearly with time. The governing equations involved in the present analysis are solved by the Laplace-transform technique. The results obtained are discussed with the help of graphs drawn for different parameters. The numerical values obtained for skin-friction and Nusselt number have been tabulated. The results are found to be in a good agreement and the data obtained is in concurrence with the actual flow phenomenon.
Imazalil sulphate pesticide degradation using silver loaded hollow anatase TiO2 under UV light irradiation
Authors: Baharvand Afrouz , Ali Rusmidah , Nur Hadi
Published: October 2017

Silver loaded hollow anatase TiO2 particles with the location of silver are inside (Ag@TiO2) and outside (Ag/TiO2) the hollow TiO2 structure have been successfully synthesized by a deposition-precipitation and template methods. The effects of silver nanoparticles location on Ag@TiO2 andAg@TiO2 has been evaluated in the photodegradation efficiency of imazalil sulphate pesticide in aqueous suspension under ultraviolet irradiation. The Ag/TiO2 showed better photocatalytic performance for the degradation of imazalil sulphate, compared to Ag@TiO2 and hollow TiO2 microspheres. A higher photocatalytic activity of Ag/TiO2 compared to Ag@TiO2 and hollow TiO2 can be considered as an evidence of enhanced charge separation of Ag/TiO2  photocatalyst as confirmed by photoluminescence spectroscopy.
Can kaolin function as source of alumina in the synthesis of ZSM-5 without an organic template using a seeding technique?
Authors: Hartanto Djoko , Yuan Lai Sin , Sari Sestriana Mutia , Sugiarso Djarot , Murwani Irmina Kris , Ersam Taslim , Prasetyoko Didik , Nur Hadi
Published: October 2017

ZSM-5 has been successfully synthesized by hydrothermal method using Indonesian Bangka kaolin as the aluminium source without an organic template and preactivation by calcination utilizing silicalite and ZSM-5 seedings. There are three parameters that made kaolin a very suitable aluminium source in the synthesis of ZSM-5 by using this method. The first parameter was the presence of types of seeds (silicalite and ZSM-5). Secondly, the molar ratio of Si/Al was in the range of 40–60. Thirdly, the concentrations of NaOH were varied from 6 to 12 mol with 1800 mol water. Interestingly, the use of silicalite seed produced pure ZSM-5 zeolite, whereas analcime and mordenite appeared as side products when ZSM-5 was used as the seed. The above effects can be illustrated by the following mechanism. Kaolin was fully dissolved in the basic mixture solution containing concentrated NaOH and silica sols, and followed by the crystallization in the presence of seeds (silicalite and ZSM-5). The mechanism was postulated on the basis of XRF, XRD, 29Si and 27Al MAS NMR analyses.
The application of MWCNT to enhance the rheological behavior of drilling fluids at high temperature
Authors: Ismail Abdul Razak , Sulaiman W. R. W , Jaafar M. Z. , Aftab A. , Razi A. A. , Ibupoto Z. H.
Published: October 2017

Drilling fluid is the key component to drill oil and gas wells. The rheological behavior of drilling fluid will be affected when drilling deep wells especially at high temperature and high pressure reservoir. This research was conducted to study the effect of the nanoparticles over the rheological properties of the drilling fluid when aging at high temperature condition. Several drilling fluids were prepared using synthetic based fluids (Sarapar and Saraline) to study the effect of multi-walled carbon nanotube (MWCNT) at different concentrations. The rheological properties of drilling fluid were analyzed after aging at 250 °F and 350 °F for 16 hours. The results revealed that the addition of MWCNT improved the 10-sec gel strength by 33% and filtrate loss volume was reduced to 10% after aging at 250°F in Saraline drilling fluid. Moreover, the plastic viscosity of Saraline and Sarapar drilling fluid after addition of MWCNT was enhanced by 6% and 27% at 350 °F. Filtrate loss volume of Sarapar drilling fluid was reduced by 19 % after aging at 250 °F for 16 hours. The overall results showed that the addition of MWCNT into the drilling fluid have slightly improved the rheological properties of drilling fluids under high temperature conditions.
Density functional theory study of electronic properties of Bi2Se3 and Bi2Te3
Authors: Lawal Abdullahi , Shaari Amiruddin
Published: October 2017

Topological insulators are layered materials via van der Waals interactions with hexagonal unit cell similar to that of graphene. The exciting features of Bi2Se3 and Bi2Te3 topological insulators their zero band gap surface states exhibiting linear dispersion at the Fermi energy. We present here first principles study pertaining to electronics properties of Bi2Se3 and Bi2Te3 compound with and without spin-orbit interaction using density functional theory (DFT). Total density of state (DOS), partial density of state (PDOS) and band structure where determined by Quantum-Espresso simulation package which uses plane wave basis and pseudopotential for the core electrons, while treating exchange-correlation potential with generalized gradient approximation (GGA). From our computations, the obtained results were found to be consistent with the available experimental results.
Stability of water-in-oil emulsion in liquid membrane prospect
Authors: Jusoh Norela , Othman Norasikin
Published: October 2017

Emulsion liquid membrane (ELM) process have shown a great potential in wide application of industrial separations such as in removal of many chemicals, organic compounds, metal ions, pollutants and biomolecules. ELM promotes many advantages including simple operation, non-equilibrium mass transfer, high selectivity, low energy requirements, and simultaneous extraction and stripping process in a single step process. New development in ELM system incorporated with a green solvent (palm oil) was attempted instead of using commercial organic solvent. The important aspects must be considered for a successful ELM process is the stability of the liquid membrane. In the current work the effect of various parameter which are organic to internal ratio, emulsifying speed, surfactant concentration, and emulsifying time on green ELM stability was investigated. The results show that the most stable emulsion was observed at 3:1 organic to internal ratio, 7000 rpm speed, 3 % (w/v) surfactant concentration, and 5 minute emulsifying time. The emulsion obtained was stable up to 1/2 hour and sufficient and sufficient for extraction process. Therefore, green solvent has high potential to be applied in emulsion liquid membrane process.
Influence of implantation nitrogen gas on electrical properties of magnetic CNT-Fe3% and CNT-Fe5% composite
Authors: Sunandar Mashadi , Purwanto Patricius
Published: October 2017

The composite of CNT–Fe were made by mixing CNT and Fe powder with the variance of Fe starting from 3% and 5% weight. Then the sample is milling for 2 hours using High Energy Milling (HEM). The CNT-Fe Composite to be had done implantasion  with nitrogen gas  for 5 hour and 8 hour. The result of magnetic parameter of composite CNT-Fe3% and  CNT-Fe5%  with VSM (Vibrating Sample Magnetometer) method shows that the remanent magnetic (Mr) and saturation magnetic (Ms) increased, and the coersive magnetic (Hc) decreased with the increasing of weight percent of Fe. The result of electrical properties of  composite CNT-Fe3% and  CNT-Fe5%    using LCR instrument indicated that conductivities value of composite CNT-Fe3%  and  MWCNT-Fe5%    are  increased with the  increasing of Fe weight. The surface morphology of composite CNT-Fe3% and  CNT-Fe5%    was done with TEM (Transmition Electron Microscopy) with the result that Fe was had into CNT.
F-index of bridge and chain graphs
Authors: De Nilanjan
Published: October 2017

The F-index or “Forgotten topological index” of a molecular graph is defined as the sum of cubes of degrees of all the vertices of the graph. In this paper, we compute the F-index of bridge and chain graphs. Further using these derived results, the F-index of several classes of chemical graphs and nanostructures are computed.
Synthesis, study of structure activity relationship and evaluation of biological activities of substituted (E)-2-Benzylidene-N-Methylhyrazinecarbothioamides
Authors: Thirunarayanan Ganesamoorthy , Senbagam R. , Rajarajan M. , Manikandan V. , Balaji S. , Vanangamudi G. , Thirunarayanan G.
Published: October 2017

A series of ten substituted (E)-2-benzylidene-N-methylhydrazinecarbothioamides were synthesized from 4-methyl-3-thiosemicarbazide with substituted benzaldehydes. All the synthesized compounds were in good agreement with elemental and spectral data (UV, FT-IR, 1H NMR and 13C NMR). The assigned UV λmax (nm), IR νC=N (cm-1), NMR δ1H (ppm) CH=N and δ13C (ppm) C=N spectral data of (E)-2-benzylidene-N-methylhydrazinecarbothioamides correlated with Hammett constants using single and multi-regression analysis. From the results of correlation analysis substituent effects on the spectral data have been discussed. The antibacterial activity of (E)-2-benzylidene-N-methylhydrazinecarbothioamides have been studied with three Gram-positive pathogenic bacterial strains namely (B. subtilis, S. aureus and S. pyogens) and two Gram-negative strains (E. coli and P. aeruginosa). The antifungal activity of (E)-2-benzylidene-N-methyl hydrazones studied with three fungal species (A. flavus, A. niger, T. viride) using disk diffusion method.
Multiplication gain and excess noise factor in thin SiC avalanche photodiodes
Authors: You Heng Ah , Sun Che Cha
Published: October 2017

This work simulated the avalanche characteristics of 4H- and 6H-SiC avalanche photodiodes (APDs) at 0.1 µm, 0.2 µm and 0.3 µm avalanche widths. A Monte Carlo model with random ionization path length techniques is developed to simulate mean multiplication gain and excess noise factor in thin SiC APDs. Mean multiplication gain, breakdown voltage and excess noise factor are simulated based on the electric field dependent impact ionization coefficients with the inclusion of dead space effect. Our results show that hole-initiated impact ionization gives high multiplication gain with low excess noise factor in both devices. We observed that dead space effect is more pronounce in thin structure since it covers a significant portion of the avalanche region. In thick device structure, a high breakdown voltage is observed. A comparison between these two polytypes shows that 4H-SiC provides high multiplication gain with low excess noise factor than 6H-SiC.
Using weighted Markov SCGM(1,1)c model to forecast gold/oil ,DJIA/gold and USD/XAU ratios
Authors: Mostafaei Hamidreza , Kordnoori Shaghayegh , Kordnoori Shirin
Published: October 2017

Grey model can be counted as a potent approximation for extracting system dynamic information with only small amount of data. A weighted Markov model is appropriate for predicting the stochastic fluctuating dynamic by a transition probability matrix and normalizing autocorrelation coefficient as weighted and a single gene system cloud grey SCGM(1,1)c  model. It is applied to regulate the development trend of time series. In this paper we employed a weighted Markov SCGM(1,1)c model for predicting the Gold/Oil ,DJIA/Gold and USD/XAU ratios. By examining the forecasted results, it was concluded that the weighted Markov SCGM(1,1)c model is a reliable and effective modeling method.
Evaluation of strength characteristics for palm kernel oil - based Polyurethane (PKO-P) as a ground improvement method
Authors: Che Lat Diana , Jais Ismacahyadi Bagus Mohamed , Mohammed Kamaruzzaman , Baharom Bahardin , Samat Nastasa , Zainuddin Atiqah Najwa
Published: October 2017

Development on soft ground area cannot be avoided at certain area especially nearby coastal or marine area. At urban areas, most of the land has been fully developed and very limited space available, therefore area nearby marine region has to be explored to cater increasing in population in certain country. It is very crucial to stabilize the soft ground before any construction carried out to ensure the structure would be founded on the stable foundation system. Foundation system commonly established for deep soft ground is a pile foundation. There are certain cases whereby pile foundation system failed after completion of structure and the building has been accommodated or been utilized. It causes large settlement which contributes to the failure of structure such as longitudinal crack, sinkholes, beam fractured and so forth. Rectification works have to be done to restore foundation strength thus to prevent further settlement which can cause collapse or major failure of structure. Rectification works that commonly being done nowadays is underpinning pile whereby new pile being installed in between the existing pile to stabilize the foundation and prevent further settlement. This method rather wearisome to be carried out since it involves major excavation and disturbs the existing structure and the surrounding. Therefore it is proposed to carry out Palm Kernel Oil Based Polyurethane (PKO-P) Pile injection to overcome this problem. PKO-P pile injection is a lightweight material to prevent further settlement and the rectification works can be done very fast. No excavation is required and only a small diameter of hole is drilled on the existing slab foundation before injection of PKO-P Pile. PKO-P is a polyurethane processed from palm kernel oil which is renown of the sustainability and green materials. In this research, Unconfined Compression Test been have conducted on few samples of PKO-P materials with different ratio of polyol and isocynate to determine the compressive strength characteristics for PKO-P materials as such to evaluate the performance of the PKO-P for ground improvement. From the test that has been done, the compressive strength achieves its maximum strength at isocynate to polyol ratio of 1:0.75 with maximum compressive strength of 2.3MPa. PKO-P shows rigid characteristics at this maximum strength which produce strong material, able to resist deformation but brittles beyond the maximum stress. With further increasing amount of polyol, PKO-P shows flexible characteristics whereby it undergoes deformation but they tend not to break beyond the maximum stress. Higher elastic modulus recorded for rigid type PKO-P compare to flexible type PKO-P.
Some graph properties of the optimised degree six 3-modified chordal ring network
Authors: Een-Chien Stephen Lim , Farah R. N. , Othman M.
Published: October 2017

The interconnection topology of a parallel or distributed network is pivotal in ensuring good system performance. It can be modelled by a graph, where its edges represent the links between processor nodes represented by vertices. One such graph model that has gained attention by researchers since its founding is the chordal ring, based on an undirected circulant graph. This paper discusses the degree six 3-modified chordal ring, CHR6o3, and presents its graph theoretical properties of symmetry and Hamiltonicity. CHR6o3 is shown to be asymmetric, and can be decomposed into similar subgraphs, each consisting of only one type of node in its class if ring links are ignored. These properties aid both the development of a routing scheme and also determining lower bounds for its chromatic number. Conditions for the existence of a Hamiltonian Circuit within CHR6o3 are also discussed. The existence of a Hamiltonian Circuit within a network simplifies parallel processing as the processors can be arranged to work on a task in a linear array. An Eulerian Circuit was shown to exist in CHR6o3. The existence of an Eulerian Circuit plays a role in routing in optical networks.
Effects of rotation and chemical reaction on MHD flow past an inclined plate with variable wall temperature and mass diffusion
Authors: Rajput U. S. , Kumar Gaurav
Published: October 2017

Effects of rotation and chemical reaction on unsteady MHD flow past an impulsively started inclined plate with variable wall temperature and mass diffusion in the presence of Hall current is studied here. Earlier we [7] have studied radiation effect on unsteady MHD flow through porous medium past an oscillating inclined plate with variable temperature and mass diffusion in the presence of Hall current. We obtained the results which were in agreement with the desired flow phenomenon. To study further, we are changing the model by considering rotation and chemical reaction. The governing equations involved in the flow model are solved by the Laplace-transform technique. The results obtained have been analyzed with the help of graphs drawn for different parameters. The numerical values obtained for the drag at boundary and Sherwood number have been tabulated. Here too, the results are found to be in agreement with the actual flow.
Chromatic numbers and indices of the optimised degree six 3-modified chordal ring network topology
Authors: Chien S. L. E. , Farah R. N. , Othman M.
Published: October 2017

Graph colouring is the labelling of the elements of a graph subject to certain constraints. It is divided into vertex and edge colouring. In both cases, the assignment of labels, traditionally called colours is such that two vertices or edges must not have the same colour. This has various applications, especially in parallel computing. This paper introduces the degree six 3-modified chordal ring, CHR6o3, a parallel network interconnection topology model, and discusses its node and link colouring. Despite its asymmetry, the chromatic number of CHR6o3 cannot be generalised and must be determined specifically based on the combination of chords in each case. Cases where the chromatic index of CHR6o3 is its degree and where it is its one colour more than its degree were generalised and proven. Chromatic numbers are important in minimising the completion times of processes in parallel processing by reducing points of synchronisation, and link colouring aids processor scheduling.
Effect of surface roughness on susceptibility of Escherichia coli biofilm to benzalkonium chloride
Authors: Mohammed Jibrin Ndejiko , Wan Dagang Wan Rosmiza Zana
Published: October 2017

The inherent natural tendency of bacteria to adhere and form biofilm on both biotic and abiotic surfaces and the consequential resistance to antimicrobial treatments remained a major concerned to humanity. The surface roughness of the sand blasted and cleaned stainless steel (type 304) substrates were measured using 3D measuring laser microscope before biofilm were developed on different surface roughness under continuous nutrient supply. The effect of benzalkonium chloride (BKC) as antibacterial agent on the biofilms was investigated. A concentration of 5 mg/mL BKC exert no pronounced effect on the biofilm formed on the three surfaces as compared to the 10 mg/mL and 20 mg/mL that removed approximately 50% of the cells from the respective surfaces. Conversely, the overall effect of the three concentrations tested were significantly higher (p ≤ 0.05) on the stainless steel coupon with the least average surface roughness of 0.38 ± 1.5 µm. These observations support the hypothesis that surface profile is one of the factors that influence biofilm susceptibility to antibacterial agents and reinforced the wide spread observation that microorganisms living as biofilm tends to be resistance to antimicrobial treatment especially at lower concentrations of 5 mg/mL.
Formulation of handsanitizer with antibacterials substance from n-hexane extract of soursop leaves (Annona Muricata Linn)
Authors: Ningsih Dian Riana , Zusfahair Zusfahair , Kartika Dwi , Fatoni Amin
Published: October 2017

One of the plants which are efficacious as antibacterial is the soursop leaves. Soursop leaves were extracted by maceration using n-hexane. The extract was evaporated using rotary evaporator. Soursop leaves extract was then formulated in a gel dosage form. This study aims toformulate hand sanitizer from soursop leaves extract based on Growing Minimum Inhibitory Concentrations (MIC) of n-hexaneextract of soursop leaves, and to know the evaluation result of gel dosage with the active substance of soursop leaves extract. Testing of physical properties of the gel includes organoleptic test, dispersive power test, homogeneity, pH, and consistency test. Antibacterial activity was tested by using a diffusion method. The evaluation of the gel showed SNI standards which wereable for topical use. The organoleptic test resultedthat the dosage is odorless, transparent and gel. Homogeneity test resulted that all gel dosage concentrations are homogenous. The pH tests at concentrations of 1, 5 and 10 ppm respectively are 5.38 to 6.22; 5.48 to 6.28; and from 5.29 to 5.90. The dispersive power test resulted for 6.47 to 7 cm; 6.20 to 6.87 cm; and 6.09 to 6.59 cm. The consistency test resulted that all gel dosages are consistent in gel form.Gel dosage with extract concentrations of 1, 5 and 10 ppm can inhibit the growth of bacteria P. acne with antibacterial activity of 3.53; 3.26 and 2.20 mm.
A review on taxonomy of fuzzy graph
Authors: Hassan Nurfarhana , Ahmad Tahir
Published: October 2017

Fuzzy graph is a graph that incorporates fuzziness.  Fuzzy graph originated from the concept of Fuzzy Set and Graph.  In this paper, taxonomy of fuzzy graph is reviewed.  Several results on fuzzy graph are presented together with some examples.  The fuzzy graph introduced by Yeh and Bang is proven to be a special case of Rosenfeld’s fuzzy graph.  Two descriptions of isomorphic crisp graph are proven to be equivalent and every crisp isomorphism of two graphs is proven to be a fuzzy isomorphism.  This paper provides an underlying knowledge on fuzzy graph which is an important foundation for further development and application of fuzzy graph.
Quantile regression for analysing PM10 concentrations in Petaling Jaya
Authors: Ng Kar Yong , Awang Norhashidah
Published: October 2017

Particulate matter with diameter less than 10µm (PM10) data usually exhibit different variations as they include normal days and pollution days. This paper applied quantile regression (QR) technique to inspect the changing relationship between predictor variables and PM10 concentrations at Petaling Jaya monitoring station in the year 2014 over different PM10 distributions. For comparative purpose, multiple linear regression (MLR) using ordinary least squares (OLS) estimation approach was also performed. The QR analysis results showed that the interrelationship between predictor variables and PM10 was not consistent across the PM10 quantile distributions and hence, proved discordancy with MLR estimates. The lagged PM10 concentration was the only important factor throughout the quantile distributions of PM10. It was found that the effects of lagged PM10, temperature, carbon monoxide (CO) increased from low to high quantile distributions, while the effects of lagged humidity, east-west wind component, wind speed and nitrogen monoxide (NO) showed the otherwise patterns. The lagged NO associated significantly with PM10 at low quantiles, whereas the lagged temperature and CO associated significantly at high quantiles only. Lagged humidity, east-west wind component and wind speed correlated significantly and negatively with PM10 at low and middle quantiles. Ozone (O3), however, had effect of changing nature from positive association at low PM10 distributions to negative association at high levels. Thus, QR is helpful to provide a more complete description of predictor variable effects on PM10 at different distributions, and may assist in PM10 management especially during haze periods.
Porosity effect on unsteady MHD free convection flow of Jeffrey fluid past an oscillating vertical plate with ramped wall temperature
Authors: Mohd Zin Nor Athirah , Mohamad Ahmad Qushairi , Khan Ilyas , Shafie Sharidan
Published: October 2017

The unsteady magnetohydrodynamic (MHD) free convection flow of Jeffrey fluid embedded in porous medium past an oscillating vertical plate generated by thermal radiation with ramped wall temperature is investigated. The incompressible fluid is taken electrically conducting under the action of transverse magnetic field towards the flow. Constitutive relation of Jeffrey fluid is employed to model the governing equations in terms of partial differential equations with some physical conditions. The transformed dimensionless governing equations are solved analytically using Laplace transform technique. The impact of various pertinent parameters namely material parameter of Jeffrey fluid , dimensionless parameter of Jeffrey fluid , phase angle , Hartmann number , permeability parameter , Grashof number , Prandtl number , radiation parameter  and dimensionless time  on velocity and temperature distributions are presented graphically and discussed in details. It is observed that, the permeability parameter tend to retard the fluid velocity for ramped wall temperature but enhance the velocity for an isothermal plate. Besides that, this study shows, the amplitude of velocity and temperature fields for ramped wall temperature are always lower than isothermal plate. A comparison with the existing published work is also provided to confirm the validity of the present results and an excellent agreement are found.
Generated paths of an autocatalytic set of a secondary system of a pressurized water reactor
Authors: Mahamud Zainab , Ahmad Tahir
Published: October 2017

A graph is used to model pairwise relation between objects. In this paper, it is used to model secondary system of pressurized water reactor. The process is presented as a dynamic graph by integrating the concept of Autocatalytic Set (ACS). The graph is then transformed into an omega algebra whereby all the possible paths of the process are determined. Seven variables are identified to represent the nodes with twenty one links to indicate catalytic relations among these nodes. A programming code of C++ is developed for the identification of these 317 links.
Global convergence analysis of a new hybrid conjugate gradient method for unconstrained optimization problems
Authors: Abdullahi Ibrahim , Ahmad Rohanin
Published: October 2017

In this paper, we propose a new hybrid conjugate gradient method for unconstrained optimization problems. The proposed method comprises of beta (DY), beta (WHY), beta (RAMI)  and beta (New). The beta (New)  was constructed purposely for this proposed hybrid method.The method possesses sufficient descent property irrespective of the line search. Under Strong Wolfe-Powell line search, we proved that the method is globally convergent. Numerical experimentation shows the effectiveness and robustness of the proposed method when compare with some hybrid as well as some modified conjugate gradient methods.