Physical, mechanical, and thermal characteristics of alkaline copper quaternary impregnated oriental beech wood

The physical, mechanical, and thermal properties of Oriental beech (Fagus orientalis), which had been impregnated with the water-based, copper-containing Korasit KS material from the Alkaline Copper Quaternary group, were investigated in this study. According to ASTM 1413-07el (2007) standard, the wood samples used in the investigation were impregnated with 3 % and 6 % aqueous solutions of Korasit KS. The modulus of rupture, thermal, and water absorption tests were performed on samples of Oriental beech after they had been impregnated. Oriental beech's modulus of rupture values decreased as a result of Korasit KS impregnation. Additionally, Oriental beech had lower modulus of rupture values at greater concentrations of Korasit KS. In every water absorption period, the water absorption values of the Oriental beech impregnated with Korasit KS were higher than those of the control group. Our results showed that Korasit KS impregnation enhanced thermal properties of Oriental beech. Moreover, higher concentration levels of Oriental beech yielded better thermal characteristics of Oriental beech

Determination of some properties of guar gum added chitosan based adhesives

Most of the adhesives used in the wood industry are fossil fuel-based and cause risks to the environment and human health, especially due to formaldehyde content. In order to reduce this negative situation, research on different methods to reduce formaldehyde emissions has been carried out in recent years. Among these research, the use of bio-based adhesives attracts attention, especially because of its positive properties in terms of health. This study investigated the potential of using natural polymers chitosan and guar gum as a wood adhesive. For this purpose, guar gum was incorporated into the chitosan-based adhesive in 4 different ratios (0.06%, 0.2%, 1%, and 2%). The impact of adding different amounts of guar gum on the binding strength was assessed by measuring the viscosity of the produced glue. In addition, Fourier transform infrared spectroscopy (FTIR) analysis was performed to examine the interaction of chitosan-based adhesives with wood. The viscosity of the chitosan-based adhesive with the addition of guar gum was found to be between 1380 CP and 5264 CP. It was found that the bond strength value of the chitosan-based adhesive with % 0.2 guar gum added improved by 88% compared to the group without guar gum. It was concluded that chitosan-based glue with guar gum added has positive properties especially with its environmentalist structure and can be used in different areas

AĞAÇ İŞLERİ SEKTÖRÜNDE KİTOSANIN ODUN KORUMA MADDESİ OLARAK KULLANILMASI

Kitosan, doğada selülozdan sonra en çok bulunan amino polisakkarit olan kitinin deasetilasyonu sonucu elde edilmektedir. Günümüzde kitosan su arıtımında, kozmetikte, medikal alan gibi sektörlerde önemli kullanım alanı bulmuştur. Kitosanın çeşitli alanlarda değerlendirilmesiyle hem ekonomik açıdan kazanç hem de çevre açısından oldukça büyük yarar sağlanmaktadır. Kitosan polikatyonik yapısı sayesinde antibakteriyel, antifungal etkilere sahip olmakla beraber gerek insan sağlığına gerekse de doğaya hiçbir zararı yoktur. Kitosanın bu özelliklerini insanla iç içe olan ahşap malzemelerin korunması yönünde araştırmalar yapılmaktadır. Literatürde kitosan hem molekül ağırlığına göre hem de metalli kitosan bileşikleri sentezlenerek odun üzerinde koruyucu etkisi araştırılmıştır. Sonuç olarak bugüne kadar yapılan çalışmalar incelenerek eksik ve geliştirilmesi gereken yönleri tespit edilip irdelenmiştir.

FARKLI TUTKALLARIN KAYIN ve SARIÇAM AĞAÇLARINDAKİ YAPIŞMA DİRENÇLERİNİN BELİRLENMESİ

Bu çalışmada, poliüretan esaslı Pu-Mon ve Pu-Ma, polivinilasetat esaslı PVAc-MA22, PVAc-MA35 ve PVAc-MA50 ile yapıştırılmış Doğu kayını (Fagus orientalis L.) ve sarıçam (Pinus Sylvestris L.) odunlarının yapışma direnci, TS EN 205 esaslarına göre belirlenmiştir. Deney sonuçlarına göre, en yüksek yapışma direnci Pu-Ma (16.01 N/mm2) ve PVAc-MA35 (15.12 N/mm2) ile yapıştırılmış kayın numunelerinde, en düşük yapışma direnci ise Pu-Mon (7.98 N/mm2) ve PVAc-MA35 (7.67 N/mm2) ile yapıştırılmış sarıçam numunelerinde tespit edilmiştir. 

OTURMA MOBİLYASI TASARIMINDA BİLGİSAYAR DESTEKLİ ERGONOMİK ANALİZ

Çalışmada, insanların birebir ilişkide olduğu oturma mobilyalarının tasarımında, ergonomik kriterlerin belirlenmesi amacıyla bir “insan odaklı ürün geliştirme” yazılımının (Anybody Technology) kullanılabilirliği araştırılmıştır. Yapılan örnek uygulamada, oturma derinliği, oturma yüksekliği ve arkalık eğim açısı farklı olan 2 adet sandalyede oturan insanın kas–iskelet sisteminde oluşan yükler niceliksel olarak analiz edilmiştir. Ayrıca, 10 erkek deneğin katılımıyla uygulanan bir anket yardımı ile de bu iki farklı sandalyede oturan bireylerin çeşitli vücut bölgelerinde hissettikleri duygular niteliksel olarak belirlenmiştir. Çalışma sonucunda, ürün geliştirme yazılımından alınan veriler, anketlerden alınan veriler ile tutarlı olup, insan odaklı ürün geliştirme yazılımının tasarlanacak mobilyaların ergonomik kriterlerinin belirlenmesinde kullanılabilir olduğunu doğrulamaktadır

A new mini-external fixator for treating hallux valgus: A preclinical, biomechanical study

WOS: 000367071200010PubMed ID: 26190777Proximal metatarsal osteotomy is the most effective technique for correcting hallux valgus deformities, especially in metatarsus primus varus. However, these surgeries are technically demanding and prone to complications, such as nonunion, implant failure, and unexpected extension of the osteotomy to the tarsometatarsal joint. In a preclinical study, we evaluated the biomechanical properties of the fixator and compared it with compression screws for treating hallux valgus with a proximal metatarsal osteotomy. Of 18 metatarsal composite bone models proximally osteotomized, 9 were fixed with a headless compression screw and 9 with the mini-external fixator. A dorsal angulation of 10 degrees and displacement of 10 mm were defined as the failure threshold values. Construct stiffness and the amount of interfragmentary angulation were calculated at various load cycles. All screw models failed before completing 1000 load cycles. In the fixator group, only 2 of 9 models (22.2%) failed before 1000 cycles, both between the 600th and 700th load cycles. The stability of fixation differed significantly between the groups (p < .001). The stability provided by the mini-external fixator was superior to that of compression screw fixation. Additional testing of the fixator is indicated.Bezmialem Vakif University, Scientific Research Projects Department [9.2012/8]The present study was funded by Bezmialem Vakif University, Scientific Research Projects Department (grant 9.2012/8)

sj-docx-1-pie-10.1177_09544089221136808 - Supplemental material for The effect of different fillers, loads, and sliding distance on adhesive wear in woven e-glass fabric composites

Supplemental material, sj-docx-1-pie-10.1177_09544089221136808 for The effect of different fillers, loads, and sliding distance on adhesive wear in woven e-glass fabric composites by Edip Çetkin, Mehmet Emin Demir and Raşit Koray Ergün in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering</p