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In this study, the influence of stitch bonding on the tensile strength and tensile modulus in plain woven Twaron T-750/vinyl ester composites in the direction of thickness was examined. The effect of stitch density was investigated in longitudinal (warp) and transverse (weft) directions as a parameter. The space (opening) geometry and the deformation caused by the stitching process around stitch points were investigated. The stitching tension, stitch thread type and diameter were kept constant throughout the study. An increase in the tensile strength was observed for low stitching densities while there was no change in the tensile strength for medium stitching densities. A decrease in the tensile strength was observed for high stitching densities. It is especially noted that the tensile strength, which is on the transversal direction perpendicular to stitch direction, decreased with stitching density and tensile deformations initiated much earlier in this direction. It was understood that fiber deviations and resin rich areas were much more effective on these decreases compared with fiber deformation.

The pollen morphology and exine structure of 10 Mentha L. species were investigated using light microscopy and scanning electron microscopy. The pollen grains of all 11 species were hexazonocolpate with granular membranes and a circular amb, varying in shape from prolate-spheroidal to suboblate. Different colpus shapes were recognized in M. ¥ dumetorum. The exine was bireticulate in section Pulegium, and reticulate in section Menthae. A correlation was found between pollen size and chromosome number. The results indicate that the pollen characters of the genus Mentha are valuable for taxonomic applications and may be useful for classification.

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Water-distilled essential oil of Chaerophyllum byzantinum Boiss., collected from Bursa, Uludag, in Turkey, was analyzed by GC and GC/MS. Sixty-five components were identified representing 94.6% of the oil. Sabinene (30.0%), p-cymen-8-ol (16.0%) and terpinolene (11.5%) were characterized as main constituents. The oil was tested on five Candida species and two strains of Candida albicans and showed good to moderate activity. The activity of the oil against C. glabrata was twice as good as that of ketoconazole.