European Journal of Scientific Research

Volume 134 No 2
August, 2015

Effect of Different Particle Size Conductive Filler on the Properties of Conductive Polymer Composites for Bipolar Plate Material
132-139
Hendra Suherman, Irmayani and Indra Khaidir
Abstract:
This study was focused on produced a suitable composite material to be used in the bipolar plate of polymer electrolyte membrane (PEM) fuel cells. Effect of different particle size (74µm and 5µm) of graphite (G74 and G5) loading concentration on the electrical conductivities, flexural strength, and density of hybrid G5/G74/epoxy composites was investigated. The pressure of mould, 1800 Psi was applied in 50, 60, 70 and 80 wt. % graphite loading concentration. The results showed that the particle size significantly affects of all properties and can dramatically change the electrical conductivity of hybrid G5/G74/epoxy (EP) composites. In an optimum composition, the electrical conductivity, flexural strength and density reached 90 S/cm, 30 MPa and 1.56 gr/cm3, respectively. These properties of hybrid G5/G74/EP composites pass to the requirement of the DOE.US, except the electrical conductivity less than 100 S/cm. The characterization was also conducted by scanning electron microscopy.
Keywords: hybrid composites; conductive polymer composites; graphite (G); particle size; bipolar plate.

A Smart Antenna System Based on Yagui Array Antenna
140-147
F. Ben Ghenaya, R.Ghayoula and A.Gharsallah
Abstract:
In this paper, two novel designs of smart antenna systems based on planar and circular (ring) array antenna beam forming is proposed. The antenna is the Yagi antenna and is fed by a line microstrip. The goal of the design is to construct a smart antenna beam forming systems with uniformly spaced radiating elements and with equal amplitude and phase excitation have long been used for the purpose of obtaining good omnidirectional patterns in the plane of the array.
To verify the performances of the proposed technique, a 4-elements array has been realized and tested for various types of beam configurations.
Keywords: Smart antenna, Yagi antenna, circular (ring) array antenna, planar array antenna, radiation pattern

Influence de la méthode de préparation des catalyseurs Pt-Ge/TiO2 sur leurs performances en l’hydrogénation sélective du citral en alcools insaturés
148-157
Tchirioua Ekou, Lynda Ekou, Gwendoline Lafaye, Catherine Especel, Patrice Marécot
Abstract:
Le citral [3,7-diméthyl-2,6-octadiènal] est un aldéhyde α,β-insaturé, issu de la biomasse et notamment de l’huile essentielle extraite du citronnier. Ce composé peut être valorisé par hydrogénation sélective de la fonction carbonyle conduisant aux alcools insaturés, géraniol et nérol. Ces dérivés terpéniques sont des composants clés dans les domaines de la parfumerie, des produits pharmaceutiques…
Généralement les catalyseurs monométalliques à base de métaux nobles hydrogènent préférentiellement la fonction éthylénique conjuguée à la fonction carbonyle. Cependant, la modification de ces métaux par des ajouts métalliques (Ge, Sn, Fe), l’utilisation d’un support réductible ou la méthode de préparation de catalyseurs peuvent orienter la réaction vers la formation d’alcools insaturés.
Dans cette étude, l’hydrogénation du citral (T=70°C, PH2=76 bar) est utilisée comme réaction modèle pour caractériser des catalyseurs bimétalliques Pt-Ge/TiO2. Ces catalyseurs sont préparés par les méthodes de réduction catalytique et d’imprégnation successive.
L’objectif de cette étude est de comparer ces deux méthodes de préparation par le biais de la réaction d’hydrogénation du citral. Les catalyseurs préparés par la méthode de réduction catalytique sont plus sélectifs en alcools insaturés que ceux synthétisés par imprégnation successive.
Keywords: citral; alcools insaturés, imprégnation successive ; réduction catalytique.

Efficacité au champ de quatre espèces de Trichoderma dans la lutte biologique contre Phytophthora palmivora, agent de la pourriture brune des cabosses du cacaoyer en Côte d’Ivoire
158-172
Mpika J ; Kébé B. I., Issali A. E. ; N’Guessan K. F ; Druzhinina I. S., Komon-Zelazowska M., Kubicek C. P., Aké S.
Abstract:
L’efficacité de quatre isolats de Trichoderma sp sélectionnés au laboratoire comme antagonistes à P. palmivora a été évaluée lors des essais au champ pendant deux années consécutives. Les actions de T. virens T7, T. asperellum T54, T. spirale T4 et T. harzianum T40 ont été testées sur 5 groupes de cabosses portés par 100 arbres plantés en randomisation totale, et assimilant chaque fruit à une cible aléatoire. Leur impact sur la composante du rendement, les pertes de production et les cherelles wiltées a été évalué. L’application sur les cacaoyers des quatre espèces de Trichoderma a réduit significativement l’incidence de la pourriture brune des cabosses de 36 à 80 %. T. asperellum s’est révélé plus efficace. Cette efficacité s’est traduite par une réduction du taux de pourriture brune, avec des indices d’efficacité de 60 à 78 %. Il a fourni le meilleur rendement en cabosses saines récoltées comparativement aux 3 autres espèces. Néanmoins, le flétrissement des cherelles qui est un critère d’évaluation très important relativement à la qualité des cabosses, n’a pas été modifié par les applications de Trichoderma. En conséquence, T. asperellum a été retenu comme le plus prometteur candidat de lutte biologique dans l’approche intégrée contre la pourriture brune due à Phytophthora sp., en Côte d’Ivoire. Il reste que le potentiel ainsi exprimé par T. asperellum doit être éprouvé lors des essais multi locaux, en milieu réel, selon les conditions agropédoclimatiques.
Keywords: Isolats, antagonistes, randomisation totale, cible aléatoire, incidence de la pourriture brune, flétrissement des cherelles, lutte intégrée, évaluation en station de recherche.


Novel Biopolymer for Automotive Bioplastic Bumper from Nano-cellulose Particle Sized Banana Peel Biomass
173-184
A.B.M. Sharif Hossain, Khalil Mseddi and Nasir A. Ibrahim
Abstract:
Biomass is organic, plant and animal derived source of material that can be converted into different forms of bioplastic and bioenergy using different biotechnological procedures. Biomasses can be the source of biomaterial products such as bio-plastics, bio-film, bio-plastic based vehicle bumper, bio-chemicals, bio-fuels, bioelectricity in the agro-industry, pharmaceuticals, biomedical and bioengineering aspect. This innovative study was conducted to produce bio-plastic based biomaterials for automotive use. Many investigations have been done and tested for the bio-plastic based bio-bumper in the laboratory and compared with the standard of synthetic bumper using the ASTM (American Society for Testing and Materials) standardization. Positive standards are found in the case of bio-plastic based bumper compared with plastic or synthetic bumper. Our results can conclude that it is possible to produce bio-plastic based bumper for vehicle from banana peel waste as innovative raw materials as well as an innovative method of technological innovation.
Keywords: biobumper, celluloses, biopolymer, nanao-particle, banana peel.

Edible Nano-Biopolymer Production for Drug and Capsule Coating from Corn Stalk Leaves
185-193
A.B.M. Sharif Hossain, Khalil Mseddi and Nasir A. Ibrahim
Abstract:
The study was conducted to produce the edible nano-biopolymer as sheet, capsules, or other definite shape from corn stalk new leaves without adding chemicals. The bioplastic is suitable to wrap or contain dry, cosmetics, medical, biomedical, bioengineering and sanitary products. A plastic-like material which is edible and naturally degradable according to this study is one of strategy to solve dependency on petroleum as well as environment pollution because of the nondegradable plastic. Corn stalk leaves were used to make edible nano-bioplastic for drug and capsule coating and other industrial uses. From the results, it was observed that starch and cellulose based nano-bioplastic was maintained the standards of the ASTM based synthetic polymer/plastic depending upon its different properties of absorption, ordor, fitness and chemical test. Therefore it can be concluded that both corn leaves having cellulose and starch based edible nano-bioplastic may be used for drug and capsule coating in the pharmaceutical industries.
Keywords: nano-bioplastic, drug and capsule coating, corn leaves.

Jordanians’ Youths Brand Choice for Fashion Stores: The Mediating Role of Celebrity Endorsement
194-205
Abdallah Q. Bataineh and Tasneem F. Alfalah
Abstract:
Fashion and clothing market become to a greater extent competitive in Jordan. The key players in this industry seems to be youths consumer’s aged between 18-24, since they spend more money on branded fashion. However, the key purpose of this research is to analyze the main variables that impact Jordanians youths’ brand choice for fashion stores, taking in consideration the role of celebrity endorsement as mediating variable. The research population consisted of all Jordanian youths aged between 18-24 years old; a structured questionnaire has been distributed on a total sample of 1200 from six private universities located in Amman. Statistically, according to the beta values revealed at the multiple regression tests; stylish appearance was the strongest variable that impact youths brand choice, and successively; effective sales promotion, brand image, price and social influence. Furthermore, the role of celebrity endorsement was supported as mediating variable. In view of that, the researchers offered crucial recommendations for fashion marketers to rethink about their marketing strategy formulation and implementation.
Keywords: price, social influence, brand image, stylish appearance, effective sales promotion, celebrity endorsement, brand choice, Jordan.

Effective utilization of labeling algorithms for Hippocampus segmentation
206-211
G.L.N.Murthy, B.Anuradha, CH. Siva Rama Krishna, B. Naresh Kumar Reddy and J.V.N.Ramesh
Abstract:
Atrophy analysis of human brain is desired in many cognitive related diseases. In particular, the progressive death of brain cells causes many neuro degenerative diseases like Alzheimer’s. The progression of Alzheimer’s disease can be observed by means of quantifying the Hippocampus which can be thought as center of memory, emotion as well as automatic nervous system. Analysis of shape of Hippocampus requires extracting the part from effected subject by means of segmentation. Much research has been carried out in this regard as the hippocampus segmentation is most trivial due to its complex structure. In the current paper, a novel method is proposed which is based on simple labeling algorithm after passing through subsequent steps. The significance lies in that it neither requires any atlas nor any complex algorithms.
Keywords: Hippocampus; atrophy; Histogram; Canny.

Antimicrobial Properties and Screening of Secondary Metabolites Extracted from sea anemone Anthopleura nigrescens (Cnidaria: Actiniaria: Actiniidae) on the Pacific coast of Costa Rica
212-221
Henry Borbón, Javier Alvarado-Mesén, Roy Soto and Ilena Vega
Abstract:
Marine organisms have bioactive compounds that could be used for control of human diseases and also play an important role in healing. The present study was designed to evaluate antimicrobial activity and screening of secondary metabolites of Anthopleura nigrescens extracts. Samples of A. nigrescens were collected, minced, homogenized, lyophilized and then further fractioned with diethyl ether, acetone, ethanol and water. Four fractions were tested for antibacterial and antifungal activity by using disc diffusion assay. Extracts were screened phytochemically for its chemical components. In vitro antibacterial assay of the fractions revealed that the diethyl ether extract has broad spectrum activity on Vibrio cholerae. In antifungal activity, diethyl ether extract also showed good results against Geotrichum candidum compared with other strains. The diethyl ether and acetone fractions exhibited antimicrobial activity with maximum inhibition zones of 9.0 and 6.5 mm respectively. Slightly activity was observed in the ethanol extract with inhibition zones of 2.5 mm, and no activity was observed in water fraction. Screening of secondary metabolites revealed the presence of reducing compounds, saponins, terpenes, steroids, and amino acids in the crude extract. The activities observed could be attributed to the presence of some of the secondary metabolites detected which have been formerly associated with antibacterial activity.
Keywords: Phytochemicals, sea anemones, biological activity, bioactive extracts, Anthopleura nigrescens.
JEL Classification Code: N56