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Study of the growth,reproductive biology and abundance for invasive shrimps Palaemon elegans Rathke from Garmat ali river Basrah,Southern Iraq

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Journal of Coastal Life Medicine 2016年第7期4卷 536-540页

作者： Khaled Khasaf al-Khafaji Imad Hadi al Qarooni murtatha youssef al abbad Nada Moffed Abd al-Lateef Marine Biology Department Marine Science CentreUniversity of BasrahBasrahIraq Biology Department Education College for Pure SciencesUniversity of BasrahBasrahIraq

Objective:To describe the growth,reproductive biology and abundance of the population of invasive shrimps Palaemon elegans(***)in one of the branches of Garmat ali river at Basrah,Southern ***:Monthly samples of the prawn *** were collected with a bottom hand net(40 cm,0.5 mm mesh)hauled over a distance of 10 m.A simple random sampling was conducted monthly between December 2012 and November ***:Seasonal changes were observed in the composition of the population of the species during the study year with the highest abundance in 2013 and the lowest abundance for the males was reported in January and for the females occurred in *** showed a significant correlation with the abundance of shrimps at the sampling *** largest female measured 67.90 mm while the corresponding value for males was 61.31 *** proportion of ovigerous adults rose during spring season to peak on about July and ovigerous prawns were taken in all months of the *** sex ratio indicated a preponderance of females over males in all months in the study *** females produced around 36-1324 eggs and the incubation period lasted for 11-14 days at 17-29°***:The results of the present study indicate that this species has a wide distribution range,high density,and great reproduction *** study reveals the lack of researches on this species in environments of Shatt al-Arab river and its ***,*** has most likely formed a permanent population in all the brackish waters in Basrah area.

关键词： Palaemon elegans Reproductive biology Density Population structure Sex ratio Fecundity

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Enhancement of Dimensional Stability of Rigid PVC Foams Using E-Glass Fibers

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Journal of Minerals and Materials Characterization and Engineering 2015年第2期3卷 65-75页

作者： murtatha M. Jamel Parisa Khoshnoud Subhashini Gunashekar Nidal Abu-Zahra Materials Science and Engineering Department University of Wisconsin-Milwaukee Milwaukee USA

Short cut E-glass fibers of two different lengths were used to determine the effect of glass fiber length on the dimensional stability of rigid Polyvinyl Chloride (PVC) foam in this study. Glass fibers measuring, 1/16" and 1/32" at different concentrations (0 wt% - 20 wt%) were used to reinforce rigid PVC foams;the PVC foam-glass fiber (PVC-GF) composites were extruded using a single screw profile extruder. The extruded PVC-GF composites were characterized for their dimensional stability, structural, thermal, and mechanical properties. Experimental results show that the dimensional stability, heat resistance, and storage modulus were enhanced without compromising the tensile and flexural strengths of the composites. Thermal shrinkage decreased by almost 55% in composites reinforced with 1/32" GF and by 60% in composites reinforced with 1/16" GFs, with visible improvements to the shape distortion. Overall, foam composites which were prepared with longer (1/16") glass fibers exhibited better mechanical and thermal properties than those prepared with shorter (1/32") glass fibers. Microstructural observations suggest that this is due to better interlocking between the long fibers and the foam cells, which result in better load distribution in the matrix.

关键词： Polyvinyl Chloride PVC Foam PVC Composites Polymer Composites Glass Fiber Composites Re-inforced Polymers

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Comparative Analysis of Rigid PVC Foam Reinforced with Class C and Class F Fly Ash

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Journal of Minerals and Materials Characterization and Engineering 2014年第6期2卷 554-565页

作者： Parisa Khoshnoud Subhashini Gunashekar murtatha M. Jamel Nidal Abu-Zahra Materials Science and Engineering Department University of Wisconsin-Milwaukee Milwaukee USA

Fly ash particles are usually spherical and based on their chemical composition;they are categorized into two classes: C and F. This study compares the microstructural, mechanical and thermal properties of extruded rigid PVC foam composites reinforced with class C and class F fly ash. The mechanical properties: such as tensile and flexural strength of composites containing class C fly ash were superior to the composites containing class F fly ash particles. Composites containing 6 phr class C fly ash showed a 24% improvement in the tensile strength in comparison to a mere 0.5% increase in composites reinforced with class F fly ash. Similarly, the addition of 6 phr of class F fly ash to the PVC foam matrix resulted in a 5.74% decrease in the flexural strength, while incorporating the same amount of class C fly ash led to a 95% increase in flexural strength. The impact strength of the composites decreased as the amount of either type of fly ash increased in the composites indicating that fly ash particles improve the rigidity of the PVC foam composites. No significant changes were observed in the thermal properties of the composites containing either type of fly ash particles. However, the thermo-mechanical properties measured by DMA indicated a steep increase in the viscoelastic properties of composites reinforced with class C flyash. The microstructural properties studied by Scanning Electron Microscopy (SEM) confirmed that fly ash particles were mechanically interlocked in the PVC matrix with good interfacial interaction with the matrix. However, particle agglomeration and debonding was observed in composites reinforced with higher amounts of fly ash.

关键词： Rigid PVC Foam Class C Fly Ash Class F Fly Ash Thermo-Mechanical Properties Morphology

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Mechanical Properties and Dimensional Stability of Rigid PVC Foam Composites Filled with High Aspect Ratio Phlogopite Mica

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Journal of Minerals and Materials Characterization and Engineering 2015年第4期3卷 237-247页

作者： murtatha M. Jamel Parisa Khoshnoud Subhashini Gunashekar Nidal Abu-Zahra Materials Science and Engineering Department University of Wisconsin-Milwaukee Milwaukee USA

High aspect ratio Phlogopite mica was used to enhance the dimensional stability and mechanical properties of extruded rigid Polyvinyl Chloride (PVC) foam. Mica was added to rigid PVC compound at different concentrations (0 - 20 wt%) and processed using a single screw profile extruder. PVC foam-Mica composites were characterized for their dimensional stability, and structural, thermal, and mechanical properties. Experimental results showed that the dimensional stability increased by 44% and heat resistance of the samples improved as the amount of mica increased in the composites. The storage modulus and tensile strength of the composites were also enhanced with the addition of mica. However, increasing the concentration of mica had no significant effect on the impact and flexural properties of the composites. SEM micrographs show good dispersion and orientation of the mica flakes along the cell walls of the PVC foam. Overall, the platy structure and physical properties of mica seemed to have played an important role in providing good interfacial bonding with the cell membranes of the foam, thus enhancing the dimensional stability of the PVC- Mica foam composites.

关键词： Polyvinyl Chloride PVC Foam PVC Composites Polymer Composites Mica Composites Reinforced Polymers

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