Search

Your search keyword '"Sidek, H.A.A."' showing total 122 results
Start Over Author "Sidek, H.A.A."
122 results on '"Sidek, H.A.A."'

4. Synthesis and sintering impact on the properties of willemite based glass-ceramics using rice husk waste as silica source

Author

Wahab R.A.A., Zaid M.H.M., Matori K.A., Halimah M.K., Sidek H.A.A., Fen Y.W., Abdu A., Shofri M.F.M., and Jaafar S.H.

Subjects
glass-ceramics, sintering, zinc silicate, phase transformation, photoluminescence, Chemical technology, TP1-1185
Abstract

The impact of sintering duration on willemite-based glass-ceramics (WGC) derived from the ZnO-B2O3-SiO2 host system through a conventional melt-quenching method by incorporating rice husk ash (RHA) as the silica (SiO2) source was comprehensively studied by means of physical, structural, and optical properties. The increment of sintering duration elevated the diffusivity rate resulting in a gradual increment of bulk density and linear shrinkage over sintering time. The XRD patterns affirmed the β-Zn2SiO4 phase formed after sintering at 700°C for 2 h, followed by α-Zn2SiO4 crystallization at a higher holding time. FESEM observation revealed that Zn2SiO4 embedded in the glassy solid phase and grew in equiaxed shape crystals as the holding time increased. Absorption spectra revealed the increasing trend in absorption bands with an increase in sintering duration due to the intensification of Zn2SiO4 crystallization thus escalating the green emission. Thus, this WGC will be applied as optically phosphor materials.

Published
2022
Full Text
View/download PDF

32. Effects of ZnO on dielectric properties and electrical conductivity of ternary zinc magnesium phosphate glasses

Author

Khor, S.F., Talib, Z.A., Sidek, H.A.A., Daud, W.M., and Ng, B.H.

Subjects
Electrical conductivity -- Research, Zinc oxide -- Thermal properties, Zinc oxide -- Electric properties, Glass -- Electric properties, Glass -- Structure, Science and technology
Abstract

Five different compositions of the ternary system [(ZnO).sub.x][(MgO).sub.30][([P.sub.2][O.sub.5]).sub.70-x] containing 8, 10, 13, 15 and 18 moL% of ZnO were prepared by the melt quenching technique. The complex permittivity studies were presented in the frequency range of 0.01 Hz to 1 MHz and over the temperature range of 303-573 K. The empirical data were analyzed by means of the curve-fitting technique based on Havriliak-Negami model. A small broad dipolar relaxation peak was well described at frequencies between [10.sup.3] and [10.sup.6] Hz within the range of temperatures studied, while at low frequency the spectrum was dominated by dc conduction which was evidence by 1/[omega] slope in the loss factor versus frequency plot. With increasing ZnO concentration, the dielectric ([epsilon]') and dielectric strength ([DELTA][epsilon]) both show an increasing trend while the dc conduction behaved in the opposite direction. The excessive zinc ions occupying interstitial position rather than substitutional position among the glass network and increases of the compactness of the glass structure have been suggested to be the reason behind the declining values of the dc conduction. Key words: Dielectric properties, conductivity, harviliak-negami, INTRODUCTION Phosphate glasses are both scientifically and technologically important materials because of their structural versatility to accept several cation and/or anion exchanges. These features allow the reengineering of glass formulation, [...]

Published
2009

33. Frequency behavior of a quartz crystal microbalance (Qcm) in contact with selected solutions

Author

Talib, Z.A., Baba, Z., Kurosawa, S., Sidek, H.A.A., Kassim, A., and Yunus, W.M.M.

Subjects
Quartz crystals -- Research, Quartz crystals -- Properties, Solution (Chemistry) -- Research, Science and technology
Abstract

Abstract: A device was constructed to monitor viscosity of solutions using fundamental frequency of 9 MHz and 10 MHz quartz crystal. Piezoelectric quartz crystals with gold electrodes were mounted by [...]

Published
2006

34. Optical characterization of lead-bismuth phosphate glasses

Author

Sidek, H.A.A., Hamezan, M., Zaidan, A.W., Talib, Z.A., and Kaida, K.

Subjects
Bismuth -- Research, Bismuth -- Analysis, Diffraction -- Analysis, Refractive index -- Analysis, X-rays -- Diffraction, X-rays -- Analysis, Lead oxide, Science and technology
Abstract

Abstract: Systematic series of lead-bismuth phosphate glasses, where PbO, [Bi.sub.2][O.sub.3] and [P.sub.2][O.sub.5] content change for every series based on their weight percentage have been prepared. The optical properties were measured [...]

Published
2005

Catalog

Books, media, physical & digital resources
See catalog results