Wettability and surface roughness characteristics of medium density fiberboard panels from rhododendron (rhododendron ponticum) biomass

Wettability and surface roughness properties of medium density fiberboard (MDF) panels made from Rhododendron biomass were examined in this study. Rhododendron dominates the understory layer of the forests throughout the Black Sea Region in Turkey with substantial biomass potential. This study was conducted to evaluate suitability of Rhododendron fiber for MDF production. For the experiments, rhododendron and commercially-manufactured-chip (Pinus sylvestris L. and Quercus robur L.) with 11% moisture content were used. The mixing ratios of rhododendron with commercially-manufactured-chip were 100:0, 75:25, 50:50, 25:75 and 0:100 %, respectively. Commercial urea formaldehyde (UF) adhesive was used as a binder. A stylus method was employed to evaluate the surface characteristics of the samples. Roughness measurements by the stylus method were taken perpendicularly to the fiber. There was a significant diff erence (p=0.05) between surface roughness parameters (Ra, Rz, Rq, and Ry). Th e results obtained in this study revealed that all the panels have met the general purpose-use requirements of European Norm (EN). It was found that panels made with a 25/75 ratio of rhododendron to commercially-manufactured-chip had a significantly lower contact angle (88.14o) than panels made with a 100/0 ratio (117.91o). Surface roughness measurements are based on four roughness parameters, average roughness (Ra), mean peak-to-valley height (Rz), root mean square roughness (Rq), and maximum peak-to-valley height (Ry) were considered to evaluate the surface characteristics of the panels and supported the above findings as the panels made with a 25/75 ratio had a slightly rougher surface with average values of 2.929 μm (Ra). From the tests performed, we conclude that increasing the rhododendron mixing portion increased surface roughness and decreased wettability. Based on these results, rhododendron biomass could be an alternative raw material for MDF manufacturing

Morphometric Features of The Proximal Tibia in Turkish Society and Its Clinical Significance

Aim:The purpose of this study was to determine the morphometric and anthropometric features of the proximal part of the tibia and to compare these features with other communities.Materials and Methods:From the collection of Anatomy Department Laboratory, Faculty of Medicine, Suleyman Demirel University, 44 tibia were included in this study. The gender determination of tibias were made on the basis of previous anthropometric and morphometric studies . Then the upper, medial and lateral photographs of tibia were taken and installed to the computer. The anterior-posterior length of the medial condyle (MAP), anterior-posterior length of the lateral condyle (LAP) and transvers length of the margo lateralis of lateral and medial condyle of tibia (TML) were measured with the image J program. In addition, the posterior slope of the medial and lateral condyle of tibia with transverse plane was measured according to the anterior, median and posterior longitudinal axis.Results:In our study, it was observed that the value of the MAP, LAP and TML is greater in men. In our study, MAP values were different from Chinese and caucasians with men and women, but TML values were close to the Chinese. LAP values were similar to Chinese and caucasians with women, but different for men. Medial posterior slope (MPE) and lateral posterior slope (LPE), there was no statistically significant difference between the sexes according to the anterior, median and posterior longitudinal axis of tibia in Turkish society. MPE measurement of tibia according to the anterior, median and posterior longitudinal axis was significantly different from Chinese and caucasians in males and females in Turkish society. LPE measurement of tibia according to the anterior, median and posterior longitudinal axis was not significantly different from Chinese and caucasians in males and females in Turkish society.Conclusion:It was observed that, features of the proximal part of the tibia was generally different from the Chinese and Caucasians in Turkish society. Establishing standards is essential for the MPE and LPE measurements for longitudinal axis of the tibia and it is considered that taking into consideration the proximal morphometric features of tibia for the prosthesis to be used in orthopedic procedures such as total knee arthroplasty