10 results for “W. Mahmood Mat Yunus”

Research ArticleOpen accessIn the author namesOptical Properties of Crosslinked Chitosan Thin Film with Glutaraldehyde Using Surface Plasmon Resonance TechniqueYap Wing Fen, W. Mahmood Mat Yunus, Mohd Maarof Moksin et al.Problem statement: The aim of this research is to study the optical properties of crosslinked chitosan thin film with glutaraldehyde using Surface Plasmon Resonance (SPR) technique. Approach: The crosslinked chitosan is synthesized by homogeneous reaction of medium molecular weight chitosan in aqueous acetic acid solution with glutaraldehyde as crosslinking agent. Four different amount of chitosan, i.e., 0.40, 0.50, 0.60 and … …American Journal of Engineering and Applied Sciences, Vol. 4, Issue 1 · 28 Jan 2011 · 9,633 accessesView PDF Cite

Research ArticleOpen accessIn the author namesEffect of Thickness of Tris (8-Hydroxyquinolinato) Aluminum on the Photoluminescence and I-V Characteristic of Organic Light Emitting StructureLim Mei Yee, Wan Mahmood Mat Yunus, Zainal Abidin Talib, Anuar KassimProblem statement: How the thickness of the tris (8-hydroxyquinolinato) Aluminum (Alq3) effect the optical and electrical properties of organic light emitting diode. Approach: The optimum thickness, photoluminescence and current-voltage characteristic of Alq3 layer on N, N-bis (inaphthyl)- N,N-diphenyl-1,1-biphenyl-4,4-diamine (55 nm) layer in Organic Light-Emitting Devices (OLED) structure are reported. Alq3 and NPB organic layers are used as Electron Transport Layer … …American Journal of Applied Sciences, Vol. 7, Issue 9 · 30 Sep 2010 · 8,253 accessesView PDF Cite

Research ArticleOpen accessIn the author namesSingle Beam Z-Scan Measurements of Nonlinear Refraction and Nonlinear Absorption Coefficients in Silver Nano-FluidEsmaeil Shahriari, W. Mahmood Mat YunusProblem statement: The nonlinear refractive index and nonlinear absorption are two important optical phenomena which are extensively used in optical switching, optical limiting and labeling. Approach: In the present research we had measured nonlinearity of Ag nano-fluid prepared using γ-irradiation method. The measurement was carried out using a single beam z-scan technique. Under a CW laser beam excitation operated at … …American Journal of Engineering and Applied Sciences, Vol. 3, Issue 1 · 31 Mar 2010 · 9,645 accessesView PDF Cite

Research ArticleOpen accessIn the author namesEffect of Sr Substitution on Structure and Thermal Diffusivity of Ba1-xSrxTiO3 CeramicS.A. Halim, Z.A. Talib, Firas K. Mohamad Al-Asfoor et al.Problem statement: The aim of this research was to study the effect of Sr substitution on structure and thermal diffusivity of Bal-xSrxTiO3 ceramic at room temperature. Approach: Structural and thermal diffusivity of Ba1-xSrxTiO3 were studied by performing X-ray diffraction and photoflash measurements. The effects of Sr substitution on the structure and on the thermal diffusivity of Ba1-xSrxTiO3 (0≤x≤1) were investigated. … …American Journal of Engineering and Applied Sciences, Vol. 2, Issue 4 · 31 Dec 2009 · 8,778 accessesView PDF Cite

Research ArticleOpen accessIn the author namesRefractive Index and Fourier Transform Infrared Spectra of Virgin Coconut Oil and Virgin Olive OilW. Mahmood Mat Yunus, Yap Wing Fen, Lim Mei YeeThis study presents the refractive index and FTIR spectra of virgin coconut oil and virgin olive oil that have been measured in the wavelength range from 491.0-667.8 nm. The measurement of refractive index was carried out using a minimum deviation method while the IR transmission ranging from 600-4000 cm-1 was measured using FTIR spectrometer respectively. The measurements were done at … …American Journal of Applied Sciences, Vol. 6, Issue 2 · 28 Feb 2009 · 13,164 accessesView PDF Cite

Research ArticleOpen accessIn the author namesPhotoacoustic Measurement of Thermal Diffusivity of Polypyrrole Conducting Polymer Composite FilmsM. Y. Lim, W. Mahmood Mat Yunus, A. Kassim, H.N.M.E. MahmudThe thermal diffusivity has been measured for the Polypyrrole-Polyethylene Glycol (PPy-PEG) composite films by the open photoacoustic method. The experimental data were analyzed for thermal diffusivity by fitting procedure. The different process parameters such as different concentrations of insulating polymer, monomer and electrolyte and the different voltages used to prepare the PPy-PEG composite films brought changes in thermal diffusivity. The … …American Journal of Applied Sciences, Vol. 6, Issue 2 · 28 Feb 2009 · 7,700 accessesView PDF Cite

Research ArticleOpen accessIn the author namesThermal Effusivity Measurement of Virgin Coconut Oil-Methanol Mixtures using Photoacoustic TechniqueFiras Kamel Mohamad Al-asfoor, W. Mahmood Mat Yunus, Azmi Zakaria et al.Thermal effusivity of virgin coconut oil-methanol mixtures were measured using open photoacoustic cell technique. The samples were prepared by simply mixing virgin coconut oil and methanol using similar procedure applied for preparation of biodisel. Thermal effusivity of the sample was obtained by fitting the experimental data of photoacoustic amplitude signal to the expression of photoacoustic signal as a function of … …American Journal of Engineering and Applied Sciences, Vol. 1, Issue 3 · 30 Sep 2008 · 7,600 accessesView PDF Cite

Research ArticleOpen accessIn the author namesOptical Properties and Kinetic Behavior of Chlorine in Pure Water and Swimming Pool Water using Surface Plasmon Resonance TechniqueW.Y.W. Yusmawati, W. Mahmood Mat YunusAn optical sensor based on surface plasmon resonance phenomenon for detection of chlorine in pure water and swimming pool water is presented. The measurement was carried out at room temperature using Kretschmann surface plasmon resonance technique. When the air medium outside the metal film is changed to chlorine solution, the resonance angle shifted to the higher value. The shift of … …American Journal of Applied Sciences, Vol. 4, Issue 12 · 31 Dec 2007 · 7,366 accessesView PDF Cite