Open Journal of Physical Science (ISSN: 2734-2123)

Journal Information
EISSN : 2734-2123
Published by: African Researchers Magazine (10.52417)
Total articles ≅ 4

Articles in this journal

A. S. Dalhatu, R. Hussin, B. Ibrahim, Y. A. Yamusa, A. Baballe
Open Journal of Physical Science (ISSN: 2734-2123), Volume 1, pp 11-15; doi:10.52417/ojps.v1i1.85

Several studies showed the interesting properties of trivalent lanthanide ions when doped in various types of phosphor. Magnesium sulfoborate phosphor doped with different concentrations of Dy3+ were synthesized using solid-state reaction method at 850 °C for 4 hours. The samples were characterized by X-ray Diffraction (XRD). The excitation and luminescence properties of MgO-SO4-B2O3:Dy3+ were determined. The emission spectrum of Dy3+ ion doped MgO-SO4-B2O3 phosphor exhibit three bands at 480 nm, 573 nm and 660 nm with excitation of 386 nm due to 4F9/2 →6H15/2, 6H13/2 and 6H11/2 of Dy3+ transitions, respectively. The excitation spectrum of Dy3+ ion doped MgO-SO4-B2O3 phosphor display several bands at 347 nm, 362 nm, 386 nm, 426 nm, 449 nm and 469 nm with emission of 573 nm, which is in agreement with the ultraviolet LED (349.9–410 nm) and blue LED (450–470 nm). An intense in the emission peak at 573 nm in the yellow region was observed with the 0.5 Dy2O3. The luminescence properties of phosphor show that MgO-SO4-B2O3:Dy3+ phosphor could be potentially used as white LEDs. Dalhatu, A. S. | Department of Physics, Bauchi State University Nigeria, 65 Gadau, Bauchi, Nigeria
A. G. Sanni, O. J. Adebiyi, N. V. Okorie
Open Journal of Physical Science (ISSN: 2734-2123), Volume 1, pp 26-40; doi:10.52417/ojps.v1i1.87

The obligee and obligor of all cost-related commitments in construction contracts are governed by the conditions of contract. Like in all human engagements, risk is inevitable in construction contracts. This exploratory overview examined residual risks associated with payment provisions in Federation Internationale Des Ingenieurs-Consiels (FIDIC) and Joint Contracts Tribunal (JCT) conditions of contract in Nigerian construction industry. The selected payment provisions were advance payment, interim valuation, retention and final payment. The methodology comprises: (i) critical examination of payment provisions, (ii) scenario building of problem situations, (iii) assessing the sensitivity of the provisions to contractual conflict, and (iv) evaluating the effect on construction cost administration. Disbursement and amortization of Advance payment in FIDIC are more secured than JCT. Interim valuation in FIDIC allows the contractor to make claims for delayed issuance of interim certificate but FIDIC does not give the contractor such right because all application for payments must be made by the contractor to the engineer. It would take a contractor in FIDIC-based contract a longer time for maturity of final payment than in JCT-based contract. It is recommended that a contractor in FIDIC-based contract should get retention bond in lieu of deduction of retention money to enhance its liquidity. Sanni, A. G. | Department of Quantity Surveying, University of Benin (UNIBEN), Benin City, Nigeria.
I. Bulus, J. K. Sheyin, E. Yayock, A. S. Dalhatu
Open Journal of Physical Science (ISSN: 2734-2123), Volume 1, pp 1-10; doi:10.52417/ojps.v1i1.84

Improving the optical response of glass host with two or more strong network formers via suitable controlled of rare earth ions is the key issue in the fabrication of optical based glass for solid state lasers and light emitting devices. Hence, we report the Nd3+ concentration dependent on optical parameters such as absorption edge, optical band gap (direct and indirect) and Urbach’s energy of gadolinium borophospho-tellurite glasses with chemical composition of 10Gd2O + 30B2O3 + 20P2O5 + (40-)TeO2 + Nd2O3 (where 0.0 ≤ x ≤ 1.0 mol%). The glass samples were synthesized by convectional melt quenching method and characterized through X-Ray Diffraction (XRD) and Ultraviolet Visible Near-Infrared (UV-Vis-NIR) measurements. The amorphous nature of these glasses was confirmed by X-Ray diffraction pattern while the UV-Vis-NIR spectra revealed six absorption peaks corresponding to the transition from ground level 4I9/2 to the various excited state of Nd3+ ions. It was found that the investigated range of Nd3+ doping concentrations has a great influence on aforementioned parameters. The excellent optical features established in the present glass host suggest their potentiality for solid-state lasers and other photonic applications. Bulus, I. | Department of Physics, School of Sciences, Kaduna State College of Education Gidan waya, Kafanchan, Nigeria
E. S. Adeniji, A. A. Bamigbola
Open Journal of Physical Science (ISSN: 2734-2123), Volume 1, pp 16-25; doi:10.52417/ojps.v1i1.86

In this study, the adsorption and corrosion inhibitive properties of ethanol extract of Dialium guineense leaves for mild steel in 0.5M HCl was studied using gravimetric method. The results obtained showed that the ethanol extract of Dialium guineense leave is a good adsorption inhibitor of Mild Steel in 0.5M HCl. The inhibition efficiency was found to increase with increase in the concentration of ethanol extract of Dialium guineense leave but decreased as the temperature increases. The inhibition efficiency increases up to a maximum of 92%. The kinetic study was found to follow pseudo first order reaction with high correlation. Thermodynamic consideration reveals that adsorption of ethanol extract of Dialium guineense leaves on mild steel surface is exothermic, spontaneous and fitted the Langmuir adsorption isotherm. The value of activation energy and Gibb’s free energy obtained were within the range of limits expected for the mechanism of physical adsorption. Adeniji, E. S. | Department of Chemistry, Ahmadu Bello University (ABU) Zaria, Kaduna State, Nigeria
Back to Top Top