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A single feed circularly polarized c-shaped and circular patch antenna with improved axial ratio bandwidth is presented. In this article, both c-shaped slots and circular patch antenna were designed and by using the concept of switches like PIN diodes the circular polarization have been obtained. In this article the circular polarization was achieved by creating some asymmetry in the structure of an antenna. The performance characteristics of an antenna were explained in terms of its return loss characteristics and elevation radiation pattern of gain by using IE3D simulator.

The concentration and distribution of heavy metals (Cd, Pb, Cr, As, Ni, Zn, Fe and Cu) lead, in soils of Warri and environs were examined using Atomic Absorption Spectrophotometer, in the rainy and dry seasons. A total of forty-eight soil samples were collected from parks, commercial areas, main roadside, from residential areas, and from industrial areas, as well as from control sites. The range of mean heavy metal concentrations during the rainy season were: Pb: >0.01 – 0.21mg/kg, Cd: >0.01 – 0.01, Cr: >0.01 - 2.61, As: >0.01, Ni: >0.01 – 0.17, Cu: >0.01 – 7.21, Fe: 0.44 – 1348.66, and Zn: >0.01 – 21.12. The range of mean heavy metal concentrations during the dry season were: Pb: >0.01 – 1.11mg/kg, Cd: >0.01 – 5.92, Cr: >0.05 – 6.12, As: 0.001- 0.01, Ni: >0.01 – 0.34, Cu: >0.01 – 8.12, Fe: 0.87 – 1451.02, and Zn: >0.01 – 19.58.The mean concentrations of heavy metals obtained in all the soil samples in the study area showed an increasing order of As>Cd>Pb>Ni>Cr>Zn>Cu>Fe in both rainy and dry season. The concentrations of heavy metals studied in soil of all sites in dry season were slightly higher than those in the rainy season. Hierarchical cluster analysis (HCA) was employed in order to further ascertain the sources of heavy metal in soils of the study area, and it revealed that the heavy metals in all the sampled media had a common origin and were associated with anthropogenic activities in the study area. Pearson’s correlation of heavy metals in the samples showed strong relationships among metals suggesting a similar distribution pattern and a combination of natural and anthropogenic sources. Spatial distribution maps of the study area showed that patterns of heavy metals were associated with several factors which include industrial activities such as gas flaring, high traffic density, and the geology of the study area. While measured concentrations are within international limits, there is cause for concern since metal concentrations in the sediment and surface water samples were elevated near some indusrial areas. Therefore, regular monitoring of the soils is essential to prevent excessive build-up of the toxic heavy metals in the soils and water resources of the study area.

This research work deals with analysis of simply supported rectangular plate under two different types of loading viz. centrally applied point load and uniformly distributed load (UDL). Four different sizes of plates were considered depending on the shape of material that allowed in the experiments. These plates were assumed to be constructed by isotropic material and subjected to point loading & UDL. The plates were supported under standard simply supported conditions at the two ends (left & right end views from the operator) so that the moment singularity is assumed at the tip of internal line support. Plate deflections were measured for all the plates under different loading conditions. These values were then validated using the ANSYS software. The results then compared and error was found out. The physical quantities of the plates and the extent of contact related to the level of loading in the case of free contact are provided in the present work.

Tooth wear or tooth surface loss is a term used to define surface loss of dental hard tissues from causes other than developmental ones, dental caries and trauma 1. Often tooth wear is always presented with myriads of clinical presentation such as erosion, attrition, abrasion and abfraction. It is crucial to understand the definition of each tooth wear aetiology and identify them during clinical examination. As this will affect the clinical management of the patients and their treatment outcome later. In the present article, the focus is placed on dental erosion in bulimic patient. Dental erosion is the irreversible loss of dental hard tissue caused by chemical process of acid dissolution but not involving bacterial plaque acid, and not directly associated with mechanical and traumatic factors, or even dental caries. 

Graviola, Annona Muricata, leaves is known for its efficacy in the treatment and management of complex disorders in man. Most research work available however targets on their organic contents, viz. essential oils, glycosides, vitamins, alkaloids and other active components. This research work aimed at investigating their elemental composition which is most often overlooked, though they play important roles in the fight against diseases. In order to determine the presence of these elements, even at trace levels, and to minimize chemical contamination during sample preparation, the sensitive analytical technique (which is free from the use of chemicals), instrumental neutron activation analysis (INAA) was used. Potassium, Ca, Cl, Mg, Fe, Na, Br, Mn, Cu, Cr and Co were present in the leaves at detectable concentrations. The concentrations of the elements Cu, Fe and Mn were found to be below their tolerable upper intake levels. The presence of these elements in the leaves of Annona Muricata indicates its potential for use in medicinal preparations for the management and treatment of certain diseases.

The main propose of this research is the analyses of value added rule as an intellectual index on the financial ,economical and stock market performance of corporations .at this research the effect of value added (intellectual capital and used capital)on the financial ,economical and stock market of corporation in Tehran exchange commission through the 2006 until 2012with the method of regression has survived .results show that the coefficient of intellectual capital value added is effective at corporation performance .although among the coefficient of intellectual capital and financial and economical performance is meaningful relationship .but there is not meaningful relation among used capital corporation performance .that is arising from not being relation among value added coefficient and financial ,economical and market performance of corporations .So we can conclude that intellectual capital value added in comparison with used capital value added has more and important effect on corporation performance especially at financial and economical performance.

The corrosion and synergistic inhibition behaviour of mild steel in H2SO4 (pH=1) in the presence of 2 mercapto Benzidazol (MBI), 2 Mercapto Benzithiazol (MBT) and 2 Mercapto 5 Methylbenzimidazol (MMBI) and potassium chloride (KCl), potassium Bromide (KBr) and potassium iodide (KI) was investigated using weight loss measurements, potentiodynamic polarization measurements and electrochemical impedance measurements. The inhibition efficiency has been found to increase with inhibitor concentration. All the three inhibitors function through adsorption followed Langmuir isotherm and made contribution with physical adsorption. It has been found the addition of potassium halides enhanced the inhibition action and the maximum enhancement has been obtained in case of the KI compared to other halides for each inhibitor. The inhibition system composed by 500 ppm MBT and 700 ppm KI offered maximum corrosion protection (~96%). On the other hand, it was found that the inhibiting effect of MBI, MBT and MMBI decreased with exposure period and temperature of the corrosion medium. The potentiodynamic results showed that these compounds suppressed both cathodic and anodic processes; preferentially acting on cathodic areas. The presence of these inhibiting species decreased the double layer capacitance and increased the charge transfer resistance, derived from Nyquist plots obtained from impedance studies. The comparative FTIR studies between pure compound and respective metal surface product indicated the presence of inhibitor in the metal surface product obtained after exposure in inhibited solutions. SEM analysis suggested that the metal had been protected from the aggressive corrosion because of the addition of the inhibitors on the surface.

The reaction of 3-Methyl-1-phenyl- 1H-pyrazol -5-amine(1) with 3-(5-Arylfuran-2-yl)-1-arylprop-2-en-1-one(2a-l), formed a novel heterocyclic compounds, 6-(5-Arylfuran-2-yl)-3-methyl-1-phenyl-4-(4-substituedphenyl)-1H-pyrazolo[3,4-b]pyridine 3(a-l). The structures of all the compounds series (3a-l) were characterized analytically. The compounds were also monitored for anti microbial activity.

Synthesis of new series of 3-[4-(1-acetyl-5-(substitutedphenyl)-4,5-dihydro-pyrazol-3-yl)phenyl]-6,8-dibromo-2-methylquinazolin-4-one has been achieved by the refluxation of 6,8-dibromo-3-{4-[5-(substitutedphenyl)-4,5-dihydro-pyrazol-3-yl]phenyl}-2-methylquinazolin-4-one with Glycial acetic acid for three hours. The intermediate have been synthesized by refluxation of 6,8-dibromo-3-{4-[3-(substitutedphenyl)prop-2-enoyl]phenyl}-2-methylquinazolin-4-one (0.01M) and 99% hydrazine hydrate (0.015M) by using ethanol (50ml) as a solvent with various aldehydes. The chemical structures of synthesized acetyl pyrazoline derivatives were characterized by their physical constants and spectral data. The new acetyl pyrazoline derivatives were screened for their antimicrobial activities against several bacterial and fungal species.

Cobalt(II) complexes with 2,4-pentanedione, salicylaldehyde and 4,4,4-trifluoro-1-(2-Naphthyl)-1,3-butanedione(tfnb) as primary ligand, ethylenediamine, 2,2'-bipyridine and 1,10-phenanthroline as secondary ligand have been synthesized and characterized by metal analysis, infrared, electronic spectral studies, conductance, magnetic susceptibility measurements and antimicrobial studies. The conductivity measurement in nitromethane indicates that the complexes and adducts are non-electrolytes while the different shifts of the carbonyl frequencies were revealed by the infrared spectral measurements. The electronic measurements are indicative of a probable six-coordinate octahedral geometry for all the cobalt(II) compounds except [Co(tfnb)2] with a probable four-coordinate square planar geometry. The ligands and the cobalt(II) compounds were screened for in vitro antimicrobial activity against ten microorganisms. [Co(tfnb)2Bipy] and [Co(tfnb)2en] showed more promising antimicrobial than antifungal activity.