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Yield and mechanical properties of veneer from Brachystegia nigerica

Journal of Forestry Research 2012年第2期23卷 295-298页

作者： babatola olufemi Department of Forestry and Wood Technology Federal University of TechnologyP.M.B.704AkureNigeria

In an effort to find suitable wood from natural forest to meet the demand for veneer products, the yield and tensile strength of veneers produced from Brachystegia nigerica were investigated. Two trees of B. nigerica were separately selected from 10 different natural forest zones while two logs were obtained from each tree. The logs were debarked and steamed in a vat prior to rotary peeling and slicing for veneer production. The optimum steam temperature was determined by considering different temperatures： 50℃, 60℃, 70℃, 80℃ and 90℃ for 24 h. Thereafter, optimum steam time was determined at the optimum temperature by considering durations of 24, 48, 72 and 96 h. The average taper of 0.75 mm per 1.0 m length was recorded for B. nigerica, indicating that the logs were reasonably cylindrical; thereby its logs are good for the production of veneer. The yield ranged from 44% to 61% with an average of 52% of the log input. The tensile strength of the veneer was tested perpendicular to grain and both peeled and sliced veneers had the highest tensile strength between 70℃ and 90℃, suggesting that softening of wood polymers, especially lignin, is between 70℃ and 90℃. The optimum temperature and time for veneer production are 70℃ and 48 h, respectively. Commercial production of veneer from B. nigerica is feasible based on the yield and mechanical properties of the obtained veneer, thereby encouraging the expansion of the scope of its utilization.

关键词： veneer Brachystegia nigerica yield tensile strength optimum steam temperature optimum steam time

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Determination of the Properties of Some Selected Timber Species for Structural Application

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World Journal of Engineering and Technology 2023年第2期11卷 319-334页

作者： Asimiyu Amobi Oyediran Catherine Mayowa Ikumapayi babatola olufemi Department of Civil and Environmental Engineering Federal University of Technology Akure Nigeria Department of Forestry Federal University of Technology Akure Nigeria

One of the alternative sustainable and green construction materials to concrete is timber. Timber is of numerous varieties, and this acts as a barrier to the extent of its usage, especially in structural application. Despite many researches on wood’s mechanical and physical properties, only a few are geared toward the structural application of wood. The present work investigated the mechanical properties of five timber species;Gmelina arborea, Tectona grandis (Teak), Terminalia superba (Afara), Ayin (Anogeissus leiocarpus), and Acacia (Robinia pseudoacacia), to determine their suitability for constructing long-span roof trusses. These are available in the South Western part of Nigeria. Their mechanical properties;bending strength, compressive strength, shear strength, tensile strength, Modulus of Elasticity (MOE), Modulus of Rupture (MOR), and density, were determined in the laboratory. The results obtained showed that all the timber types, except Terminalia superba (Afara), have higher values of mechanical properties than the values that are obtainable for classes of strength D30 to class D70 in the British Code of Practice. It means these species are of higher quality than the stipulated strength classes in the British code. The results also show that the order of relevance of the species for structural design (or work) is Acacia (Robinia pseudoacacia), Ayin (Anogeissus leiocarpus), Gmelina Arborea, and Tectona grandis (Teak). Terminalia superba (Afara) is not recommended for structural works.

关键词： Timber Wood Species Bending Strength Compression Mechanical Properties

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Prospective Evaluation of Outcomes of Mechanical Devices in Women with Symptomatic Pelvic Organ Prolapse in Ogbomoso, South-Western Nigeria

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Open Journal of Obstetrics and Gynecology 2021年第4期11卷 461-473页

作者： Akintunde Olusegun Fehintola olufemi Timothy Awotunde Olumuyiwa Ayotunde Ogunlaja Lawrence Olujire Olujide Samuel Eniola Akinola Sunday Adekunle Oladeji babatola Bakare Olurotimi Idowu Aaron Department of Obstetrics Gynaecology and Perinatology Obafemi Awolowo University Ile-Ife Osun State Nigeria Department of Obstetrics and Gynaecology Bowen University Teaching Hospital Ogbomoso Oyo State Nigeria Department of Obstetrics and Gynaecology Royal Hampshire County Hospital Winchester UK Department of Obstetrics & Gynaecology Unimed Teaching Hospital Ondo Ondo State Nigeria Department of Anaesthesia Obafemi Awolowo University Ile-Ife Osun State Nigeria

Background: Symptomatic pelvic organ prolapse (POP) impacts the sufferers’ quality of life negatively. There is a preference for a mechanical device in certain conditions though the definitive management of POP is surgical. Objectives: We conducted the study to evaluate the outcome of management of POP using mechanical devices. Methods: It was a prospective study. It took place in the gynecology unit of the Bowen University Teaching Hospital Ogbomoso between May 2014 and April 2019. We followed up with eligible patients who opted for pessary use for a median duration of 18 months (Range 12 - 84 months). We excluded those who refuse to participate in the study. Results: Of the 127 patients with symptomatic POP, seventy-five (59.1%) opted for the use of mechanical devices, and 70 successfully retained them four weeks after insertion. We lost Six (9.2%) patients to follow up. Of the 64 women included in the analysis, 16 (25%) discontinued use at so

关键词： Mechanical Device Symptomatic Pelvic Organ Prolapse Complications Dis-continuation

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