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The effect of addition of Santalum paniculatum leaves extract on the corrosion of steel in 0.5M H₂SO₄ acid has been studied by weight loss measurements, potentiodynamic polarisation and Electrochemical Impedance Spectroscopy (EIS) measurements. The inhibition efficiency was found to increase with inhibitors content to attain 59.38% and 91.66% Santalum paniculatum leaves extract on and 25ppmTBAB respectively. Data obtained from EIS studies were analyzed to determinate the model inhibition process through appropriate equivalent circuit models. Inhibition efficiency IE (%) obtained from the various methods is in good agreement.

Setting a conventional cement plug is nearly unsuccessful when there is any wellbore flow especially for the zechstein formations. As such, the used of sodium silicate remain the common option. The silicate polymerization and gelation has been used in well formation to plug holes and reduce the catastrophic flow which cause a lot of production looses. This is usually encountered during drilling rocks zone producing large amount of water or brine. This could result in large volume of the drilling fluid lost into the formation and consequently reduce the effectiveness of the drilling operations. A well designed silicate/cement material forms an impermeable plug and reduces the adverse of the flow also the in-situ gelation of the process is better understood when the chemistry of the process and the chemical evolution of the brine formation is given due consideration.

The inhibitive effect of the extract of Solanum torvum leaves on the corrosion of aluminium in 1M NaOH solution was studied using at weight loss method at 30 - 60?C. The extract acts as an excellent corrosion inhibitor with 91% efficiency at the highest concentration in the alkaline environment and the inhibition efficiency increased with increasing concentration of the extract. The adsorption of the inhibitor on aluminium surface decreases with rise in temperature, suggesting physical adsorption of the organic matter on the metal surface. These results were supported by kinetic and thermodynamic parameters for corrosion and adsorption processes calculated from the experimental data at the various temperatures studied.

One of the most important and challenging problems for seamless access of wireless and mobile services is mobility management, which will be regardless of the services and networks. Mobility management enables the Mobile (MT) to switch between networks for better resource management and is still a hot research topic. With so many handover algorithms available, how to evaluate and select the best algorithm becomes critical, thus making handover algorithms one of the essential components for the successful implementation of mobility. These algorithms need to be designed to provide the required Quality of Service (QoS) over a wide range of applications. This work is based on new criterion called Wrong Decision Probability (WDP) which is used to evaluate the performance of vertical handover algorithms and is based on signal strength (SS) and the available bandwidth (BW), which are combined together to obtain a better decision for handover. This paper proposes a new user centric algorithm for vertical handovers, which minimizes the wrong decisions during a handover process and maximize the user throughput by taking into account Bandwidth and Signal Strength of the network.

Copper (II) phthalocyanine and 2, 9, 16, 23 tetrakis nitro copper (II) phthalocyanine  has been synthesized respectively from phthalonitrile and 4-nitro phthalonitrile under solvent-free condition using two different catalysts. 4-Nitro phthalonitrile synthesized from phthalimide in three steps. The reaction time of ruthenium chloride and HZSM-5 catalysts was very shorter than ammonium molybdate and H? catalysts. The yield while we used ruthenium chloride and HZSM-5 catalysts were very higher than another. The newly prepared compound has been characterized by IR, UV-Vis, ¹HNMR and XRD spectra.

Studies on synthesis, characterization, antimicrobial and antioxidant properties of some metal(II) complexes of the mixed ligands, Vitamins B2 (Riboflavin, HL) and Benzoic acid (HL2), where M = Mn, Fe, Co, Ni, Cu and Zn were carried out. The conductivity measurements and percentage metal analysis confirmed that the metal complexes were covalent in DMS with the formulations [M(HL)(HL1)Cl2] and [M(HL)(HL1)SO4]. The room temperature magnetic moments and electronic spectra measurements were corroborative of 6-coordinate, octahedral geometry for all the metal complexes. In addition, the Fe(II), Co(II) and Ni(II) complexes exhibited spin-crossover, the Mn(II) and Cu(II) complexes were dimeric and the Zn(II) complex was mononuclear. The infrared spectra data showed that the coordination in the metal complexes occurred through the hydroxy oxygen atoms in Riboflavin, and the carboxylate oxygen atoms in Benzoic acid. The antimicrobial screening of the metal complexes against Escherichia coli, Proteus spp, Streptococcus pyogenes, Candida albicans, Salmonella sp, Streptococcus sp, Bacillus spp, Staphylococcus sp and Pseudomonas spp revealed that the Co(II) complex had the best activity with inhibitory zones range of 7.0-20.0 mm. The antioxidant screening of the metal complexes showed that [Cu(HL)(HL2)Cl2] had the best activity with percentage inhibition of about 50.0 which was about twice that of the standards, Ascorbic acid and ?-tocopherol, proving its potentials as an anticancer agent.

Nonlinear optical L-Alanine Lithium Nitrate (LALN) single crystal was grown by slow evaporation solution method at room temperature. The title compound was characterized by various methods such as UV-Vis Spectroscopy, powder X-ray diffraction and Fourier Transform infrared (FTIR) Spectroscopy. The grown LALN was found to crystallize in orthorhombic system with space group P212121. The SHG efficiency of LALN was found to be 0.42 times that of potassium dihydrogen orthophosphate (KDP) and 0.12 times that of urea.

In the present study, herbicide 2,4-D was investigated for its potency to induce oxidative stress and its effects on antioxidant systems in gill and liver tissues of (Xiphophorus hellerii). Animals were exposed to sublethal doses of 2,4-D for 96 hours except for the control group. Protein, malondialdehyde, catalase and acetylcholine esterase enzyme activity (AChE) were determined using spectrophotometric methods. The results show that protein levels were reduced in all experiments when compared to control group. Levels of malondialdehyde were increased in each group. Catalase enzyme activity was significantly decreased in all groups. In addition, an increased AChE activity was observed.

This article was written with the aim of examining the differing views of the scholars of the art of the trope in the subject of mental trope or tropical predication and tries to compare the different aspects of scholars’ views with an analytical and descriptive method and finally with the help of those scholars’ views and studying the historical evolutionary course of that rhetorical device give a fruitful result to the lovers of the this art. Mental trope is one of the devices of the rhetoric in general and art of the trope in specific that the domain of dialectic and arguments about it goes back to the history of rhetoric and it came to known as propositional trope, trope in proof, and tropical predication. Mental trope is generally about the construction and the structure of the sentence and is beyond the boundary of the word; that is, each single word of the sentence is used in its conventional meaning, however, the construction of the sentence is not in agreement with its real concept. In other words, the verb and verbal group (infinitive, gerund, and past participle) is attributed to an agent other than its real agent.

The Universe is globally hyperbolic as we did prove mathematically [S. A. Mabkhout, Phys. Essays 25, 112 (2012)]. The solution predicts the equation of state of cosmology ( P = -???? ). Penrose said if the curvature is not equal to zero, then inflation is out. The hyperbolic universe inflates exponentially produces an accelerated expansion of the universe without cosmological constant or scalar field, as we have shown [S. A. Mabkhout, Phys. Essays 26,422 (2013)]. “In testing the validity of any scientific paradigm, the key criterion is whether measurements agree with what is expected given the paradigm”1. The hyperbolic time evolution equation of the universe (the hyperbolic scale factor) fits the observed data and successfully predicts the Planck length (10-33 cm) at micro-cosmos scale as well as it predicts the current observed large structure (1028 cm) at macro-cosmos scale, thus connecting both General Relativity and Quantum Theory. The distance horizon in the flat universe is 14 Gpc. We found the distance horizon in the hyperbolic universe to be infinitely, thus solves the horizon problem. Although the perspective for nearby objects in hyperbolic space is very nearly identical to Euclidean space (i.e., the universe locally is approximately flat consistent with local observations, the apparent angular size of distant objects falls off much more rapidly, in fact exponentially. The universe is globally hyperbolic. Locally the spacetime is approximately flat, by means of the hyperbolic inflation. . Locally any deviations from flatness will be hyperbolically suppressed by the hyperbolic expansion of the scale factor, and the flatness problem is solved.