Open Access Original Research Article

Electrical Properties of Electrodeposited Lead Selenide (PbSe) Thin Films

K. I. Udofia, Ikhioya I. Lucky

Asian Journal of Physical and Chemical Sciences, Page 1-7
DOI: 10.9734/AJOPACS/2018/40383

PbSe thin films were electrodeposited onto ITO substrate with variation of deposition voltage (1-5V). The deposited thin films were characterized using the four point probe technique to determine their electrical properties.  The sheet resistivity of the thin films was found to vary from 1.50 x104 (Ωm) to 5.23 x 104(Ωm) and conductivity vary from 1.91 x 10-5 (Ωm)-1 to 7.40x10-5(Ωm)-1, which is within the electrical conductivity range for semiconductor. It was observed that as the refractive index of the incident radiation increases the photon energy increases as well. It was noticed that sample N with 168nm thickness recorded the highest value of refractive index which increases from 2.424-2.643 and sample O with 164 nm thickness revealed the highest peak in all the samples deposited. It shows that as the optical conductivity of the incident radiation increases the photon energy increases. It was observed that sample follows the same thread and sample O with 164nm thickness revealed the highest peak in all the samples deposited.

Open Access Original Research Article

Instability of Space-time Continuum from the Standpoint of ZPF Field in a Vacuum

Takaaki Musha

Asian Journal of Physical and Chemical Sciences, Page 1-7
DOI: 10.9734/AJOPACS/2018/40340

By applying quantum tunneling effect for photons generated from ZPF vacuum, it is considered that some of them can be generated as superluminal particle.

If they have electric charges, they radiated electromagnetic energy by the Cherenkov effect. This leads to another explanation of the origin of Cosmic Background Radiation, which is distributed uniformly over the space. From this standpoint, it can be shown that the upper limit of temperature can be existed at about  Kelvins, which is too low compared with the estimation by String theory.

If temperature in the space including electromagnetic energy becomes more that this upper limit of temperature, the space-time continuum becomes instable because negative energy can be generated by tachyon field.


Open Access Original Research Article

Geoelectrical Subsurface Imaging for the Mapping of Leachate and Contaminant Plume around Septic Tanks Within the Staff Quarters in University of Benin, Benin City, Nigeria

V. B. Olaseni, Y. S. Onifade, J. O. Airen, O. M. Alile

Asian Journal of Physical and Chemical Sciences, Page 1-10
DOI: 10.9734/AJOPACS/2018/40338

2-Dimensional imaging was used to investigate the presence of leachate and contaminant plume around septic tank within the Staff Quarters in University of Benin, Benin City, Nigeria. This conventional 2-D electrical resistivity survey method was carried out by engaging the Wenner Alpha array configuration using PASI 16 GL Terrameter. Four traverses with a spread of 160 m each were covered around the septic system using DIPRO and RES2D Inversion software for interpretation so as to delineate the plume and probable trend of migration. To test for the presence of heavy metals, Physiochemical analyses were done on the water collected through the borehole that was very close to the septic system. The interpretation of the inverted 2-D electrical resistivity data revealed five subsurface layer: topsoil, clayey sand and sandy layers, clayey sand and sand zones constitute the major aquifer units in the study area. The 2 D Inversion delineated contamination plumes as low resistivity zones. As revealed by the inversion model, there was a strong evidence of vertical and horizontal plume migration westwards in third layer of traverse 1 and 2. Also, traverse 3 displayed a low resistivity anomaly ranging from 60 Ωm to 109 Ωm (15m below the surface) in third layer. It was only traverse 4 that showed a strong evidence of horizontal plume in top soil with a low resistivity <100 Ωm at a depth of 0 to 4 m with a lateral distance of 10 to 160 m. Also, there was strong evidence of topsoil contamination in traverses 2 and 4 (resistivity < 100 Ωm) and this constitutes the contaminated shallow water zone. This low resistivity zone, occasioned by infiltration of leachate from the septic tank. For physiochemical analysis on heavy metals, and with exception of pH, other parameters analyzed compared favourably with WHO, and ASTMD standard for drinking quality water. The pH values of 5.84 obtained from water samples were below 6.5-8.5 as recommended by WHO and this shows that the site was acidic, and a clear evidence of physical pollution exist. However, sodium carbonate should be used as a purifier for acidic groundwater also, future borehole should be constructed beyond far away from the pollution source (septic system).


Open Access Original Research Article

Equation Validating Kinetic Parameters Must be Dimensionally Valid: General Equation of Rate Constant in Focus

Ikechukwu I. Udema

Asian Journal of Physical and Chemical Sciences, Page 1-11
DOI: 10.9734/AJOPACS/2018/40904

Objectives: The objectives of this research are 1) to examine the units of parameters in quasi-steady state approximation (QSSA) equations (inequalities) with a view to confirming or otherwise the dimensional consistency, 2) to slightly modify the general equation of rate constant or ES as molar concentration of enzyme involved in complex formation, 3) to justify or otherwise the shift from free substrate to total substrate intended to extend the validity of standard QSSA otherwise called total QSSA,

Study Design: Theoretical and Experimental.

Place and Duration of Study: Department of Chemistry and Biochemistry, Research Division of Ude International Concepts LTD (862217), B. B. Agbor, Delta State, Nigeria; Owa Alizomor Secondary School, Owa Alizomor, Ika North East, Delta State, Nigeria. The research, including the derivation of equations, lasted between 10th Jan 2018 and 3rd Mar 2018.

Methodology: Bernfeld method of enzyme assay was used. Assays were carried out on Aspergillus oryzea salivary alpha-amylase.

Results: The total mass concentration of substrate as against free substrate values were < total substrate concentration at the time, t = o; both rate constant and total substrate (concerning mass conservation) showed increasing trend with increasing concentration of substrate, S.

Conclusion: The number of moles of each product, cannot be > the number of moles of enzyme-substrate complex. The molar concentration of bound enzyme can be calculated (Eq. 16). Equation (34) divided by molar mass gives a similar result as Eq. (16). The general rate equation needs the molar mass as denominator to be dimensionally consistent (Eq. (36)). The shift from the free substrate to "total substrate" seems valid going by the similarity between [ST] - MP and Eq. (19),           Eq. (23), and Eq. (32b). The kinetic constants seem to satisfy mainly the condition for validity of rQSSA.


Open Access Original Research Article

Application of Novel Eco-friendly Natural Dye Extracted from Leaves of Neem on Silk Fabric

Nabawia A. Abdel-Zaher, Amal A. El-Ebissy, Ebtsam S. Al-Amoudy

Asian Journal of Physical and Chemical Sciences, Page 1-16
DOI: 10.9734/AJOPACS/2018/40614

In the present work, optimization of extraction natural dye from neem (Azadirachta indica)                        leaves with respect to dye bath concentration on silk fabric was studied before and after                      exposing to artificial daylight for 160 h. The effect of different dye bath concentrations in the range 40-240 g/L on the reflectance spectra of the unexposed and exposed silk fabric was followed by using spectrophotometric technique. The absorption coefficient, optical band gap energy and extinction coefficient as well as color strength were calculated from the reflectance data                           and the wash fastness was tested. The color parameters: the relative brightness (L*), color constants (a* and b*), whiteness index (W), color difference (∆E), chroma (C*), hue (H), and tint (T) and the CIE tristimulus values (xr, yr, and zr) were also determined. The obtained results                       showed that the absorption and extinction coefficients, color strength and color parameters were highly affected by changing dye concentration. In addition, it was also noticed that the variations in the values of the optical band gap energy with increasing dye concentration may be due to the induced structural change in the system. In addition, the dyed silk samples have shown good washing fastness properties. The washing fastness grade for color change ranged from 4 to 5, whereas from 4 to 4/5 for color staining with all samples. The present study indicates that the natural dye extracted from neem leaves has good potential in textiles dyeing and meet the environmental future demands technology of high quality fantastic dyed pattern through an economical point of view.