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A spider can produce several types of silk (dragline, cocoon, etc.) which is a composite material with a hierarchical structure. This structure includes beta-sheet, polypeptide chain network and silk fibril. If the design of these bio-based materials and the relationships between protein sequence and structure-property are understandable, this knowledge can be used in technological applications ranging from medical (micro-sutures, artificial ligaments, tendons, and drug delivery coatings) to military (body armor, light weight gear) to civilian (textiles) usages [1][2][3]. The purpose of this study is to characterize the structure of silk cocoon samples which have high crystalinity and valuable protein contents. X-ray powder diffraction and SWAXS (Small and Wide Angle X-ray Scattering) methods were used for the structural characterizations. ARANEIDAE (Simon, 1895) and GNAPHOSIDAE (Pocock, 1898) families have been especially studied because of their productive properties. The crystallite size range, crystallinity percentages, number of crystallites and the distances between crystallites (depending on the direction of fibrils) have been determined. The results have been systematically evaluated and recorded as database for our ongoing TBAG project [4]. Especially in nanotechnological investigations, their superior performance under different conditions and water repellent properties attracts much attention [1][2][3][4][5]. In this study, Small and Wide Angle X-ray Scattering (SAXS and WAXS) methods were used to characterize the natural structures of poplar (populus), hornbeam (carpinus), chesnut (castanea) and walnut (juglans) trees originally form Turkey forests and their micropowders of aspen heartwood and aspen sapwood parts. After first structural comparisons , their micropowder forms, metal oxide nanopowders (aluminium, cobalt, nickel oxide etc., size range ~ 10-20 nm) and kleiberit 303 (as PVAC base adhesive) were mixed and the new substances were typically stirred for 30 min-120 min to prepare cylindirical and planar shaped nanocomposite hardboards. As secondary part of the study, SWAXS measurements have been performed for wood nanocomposites to determine the shape and distributions of nanosized aggregation. Pair distance distributions and size distributions were obtained and compared to prepare homogenous samples. Beside of these studies, moisture contents, thickness swelling of the samples and mechanical properties (strain and stress) were also determined. Acknowledgement: Authors thank Hacettepe Univ. Scientific Research Unit for the support in the project no: 06A602012

The systematic analysis of male and female genital structures of tribe Carabini, Platynini, Sphodrini and Zabrini (Coleoptera, Carabidae) species and their taxonomic importance Carabini, Platynini, Sphodrini ve Zabrini (Coleoptera, Carabidae) tribusu türleri erkek ve dişi genital yapılarının sistematik analizi ve taksonomik önemleri Research Article