Publication

Publisher:
 The Nigerian Journal Of Forestry
Publication Type:
 Journal
Publication Title:
 Impact Of Hot And Cold Treatment Techniques On Preservative Absorption Of Gmelina Arborea Wood
Publication Authors:
 Owoyemi, J.M. And Kayode, J.O.
Year Published:
 2007
Abstract:
The absorption of some selected preservatives using hot and cold treatment techniques on Gmelina arborea wood was evaluated in this study. The preservatives used are Copper Chrome Arsenate (CCA), Creosote Oil (CREO) and Cashew Nut Shell Liquid (CNSL). Hot and cold dipping methods of application were used for the treatments on Gmelina arborea wood. The result revealed that hot dipping significantly improved the uptake of the preservatives by the wood samples with percentage absorption of 9.65±4.32; While CNSL has the least absorption of 5.18±1.3 for hot treatment. 
Publisher:
 Bulletin Of Pure And Applied Sciences
Publication Type:
 Journal
Publication Title:
 Effects Of Chromated Copper Arsenate And Creosote Oil On The Resistance Of Gmelina Arborea Wood (Roxb) To Termites’ Attack
Publication Authors:
 Owoyemi, J.M. And Kayode, J.O.
Year Published:
 2007
Abstract:
The resistance of Gmelina arborea wood treated with Chromated Copper Arsenate (CCA) and Creosote Oil (CREO) was investigated. Gmelina arborea wood samples, aged fifteen years were treated with CCA (4%, 3% and 2% concentration) and CREO (Undiluted, 1:1 Kerosene and 1:3 kerosene mixture) using cold dipping method. The effect of cold dipping on the absorption of these preservatives on Gmelina arborea wood was carried out through field exposure test for 36 months (3years). Weekly visual observations were taken to determine the effect of time on the exposure of sample pieces to termite attack: Field exposure test for the varied levels of concentration of preservative treatment of Gmelina arborea showed that the wood treated with CCA 4%, 3% and 2% concentrations were able to resist termite attack for 36 months with no visible scar, while CREO treated samples were moderately resistant: Analysis of variance of the test showed that there was no significant difference (p 
Publisher:
 Journal Of Bio Technology
Publication Type:
 Journal
Publication Title:
 Effect Of Incision On Preservative Absorption Capacity Of Gmelina Arborea Wood
Publication Authors:
 Owoyemi, J.M. And Kayode, J.O.
Year Published:
 2008
Abstract:
The effect of incision on preservative absorption of Gmelina arborea wood was investigated using Copper Chrome Arsenate (CCA), Creosote Oil and Cashew Nut Shell Liquid (CNSL) preservatives. The result revealed that incising improved the uptake of the preservatives by the wood with a percentage absorption of 9.44±2.96 compared with unincised; 7.83±2.96. Using 555 incisions m2 to an incision depth of 5mm statistically showed significant difference between incised and unincised treatments. Also, there was significant difference between CCA and the other two preservatives in the absorption capacity of Gmelina arborea wood. The highest percentage absorption 13.60±1.91 was recorded for CCA, followed by Creosote Oil 7.8±0.66, while CNSL has the least absorption 6.92±0.08. 
Publisher:
 Forest And Forest Products Journal
Publication Type:
 Journal
Publication Title:
 Influence Of Preservative Viscosity On Absorption By Gmelina Arborea Wood
Publication Authors:
 Owoyemi, J.M.
Year Published:
 2010
Abstract:
The effect of preservative viscosity on fluid absorption by Gmelina arborea wood was investigated using Copper Chrome Arsenate (CCA), Creosote Oil and Cashew Nut Shell Liquid (CNSL) preservatives. Viscosity test was carried out on these preservatives using viscometer. Hot and cold dipping methods of applications were used for the preservative treatments on Gmelina arborea wood. The result revealed that hot treatment method lowered preservative viscosity and improved its uptake by the wood with percentage absorption of 9.65± 4.32 compared with cold treatments. Also, there was significant difference between CCA and the other two preservatives in the absorption capacity of Gmelina arborea wood. The highest percentage absoption of 13.94 ± 3.7 was recorded for CCA, followed by CREO with 9.84 ± 4.32, while CNSL has the least absorption of 5.18± 1.3 for hot treatment. The result of viscosity test for the preservaties when compared with absorption showed that absorption is greatly influenced by the rate of preservative applicatipon. 
Publisher:
 ProLigno International Journal In The Field Of Wood Engineering
Publication Type:
 Journal
Publication Title:
 Evaluation Of The Resistance Of Gmelina Arborea Wood Treated With Creosote Oil And Liquid Cashew Nut Shell To Subterranean Termites’ Attack
Publication Authors:
 Owoyemi J.M., Kayode, J.O. And Olaniran S.O.
Year Published:
 2011
Abstract:
This study examined the resistance of Creosote Oil (CREO) and Cashew nut shell liquid (CNSL) on the protection of Gmelina arborea wood against subterranean termites’ attack. Gmelina wooden stakes were treated with undiluted CREO and with diluted CREO/ kerosene mixtures ratio 1:1 and 1:3, using cold dipping method. Termites’ field exposure test was carried out at the timber grave yard for 36 months (3years) to test the resistance of CREO and CNSL preservatives to subterranean termites. Weekly visual observations according to American Standards for Testing Materials (ASTM) were taken to find out the effect of prolonged exposure of treated wood samples had 54.2, 65.0 and 76.0% weight loss compared to the control (untreated) sample having 86.7% respectively for the same period. CNSL treated samples had 80.0, 80.8 and 85.0% weight loss respectively compared with the control with 86.7%. These results indicated that CREO treated samples provided a better protection against subterranean termites compared with CNSL treated samples for the 36month period. 
Publisher:
 Forest And Forest Products Journal
Publication Type:
 Journal
Publication Title:
 Effects Of Age On The Natural Resistance Of Gmelina Arborea (Roxb) Wood To Subterranean Termites’ Attack
Publication Authors:
 Owoyemi J.M., Kayode J.O. And Olaniran O.S.
Year Published:
 2011
Abstract:
This study examined the natural resistance of Gmelina arborea wood to termites’ attack. Untreated Gmelina arborea wood of ages 10, 15, 20 and 25 years respectively were exposed to termites at the timber graveyard. Visual examination according to American Society for Testing Materials was carried out for a period of 18 months. The result showed that Gmelina arborea wood attained a visual rating of 3.5 and 2.8 for ages 25 and 20 years in the 18th month, 15year old wood attained a visual rating of 0 at the 18th month while the 10year old wood attained a rating of 0 at the 12th month. This result showed that the visual rating for the ages examined were tending towards zero or completely failed before the 18th month. The result indicated that Gmelina arborea wood is not naturally resistant to termites. However, the study revealed the effect of age (maturity) on the ability of the wood to withstand attack. It is therefore necessary that Gmelina arborea wood be treated with preservative irrespective of the age at which it is procured to extend its service life beyond the level of its natural durability. 
Publisher:
 Nigerian Journal Of Mycology
Publication Type:
 Journal
Publication Title:
 Fungicidal Effect Of Chromated Copper Arsenate And Cashew Nut Shell Liquid On The Treatment Of Ceiba Pentandra Wood
Publication Authors:
 Owoyemi J.M., Olufemi B. And Olaniyan M.O.
Year Published:
 2011
Abstract:
The fungicidal effect of Chromated Copper Arsenate (CCA) and Cashew Nut Shell Extract (CNSE) on the treatment of Ceiba pentrandra wood against fungal infection was investigated. Ceiba pentrandra wood samples of size 20 x 20 x 60mm were treated with CCA and CNSE preservative using cold dipping method. Absorption and retention of the preservatives using CCA at 4% concentration gave 65.75% and 10.23 kg/m3 respectively while undiluted CNSE recorded 31.4% and 0.79 kg/m3for the aforementioned respective parameters. The result of fungal exposure test for 12 weeks by soil block method revealed the efficacy of CCA in suppressing the activities of Serpula lacryman, Aspergulus wentii and Penicilium brevi – compatum on C. pentandra wood while CNSE could not provide the needed protection as there was no significant difference between CNSE treated samples and the control. 
Publisher:
 Nigerian Journal Of Environmental Management
Publication Type:
 Journal
Publication Title:
 Physical Properties Of Selected Indigenous Wood Species In Akure, Ondo State, Nigeria
Publication Authors:
 Falemara, B.C. Owoyemi, J.M. And Olufemi, B.
Year Published:
 2012
Abstract:
The identification of wood is of prime importance to primary and secondary industrial users of wood as well as to scientists in the field of botany, ecology, forestry, and wood technology. Since wood is a popular and useful material, it is important that professionals be able to distinguish the wood of one species from another. Wood can be identified by using features like mechanical strength, density, hardness, odour texture and colour. Reliable wood identification usually requires the ability to recognize basic differences in cellular structure and wood anatomy. This study was carried out to determine some physical properties of ten selected indigenous Nigerian wood species namely: Abura (Mitragyna ciliata), Afara (Terminalia superba), Araba (Ceiba pantandra), Aye (Sterculia rhinopetala), Idigbo (Terminalia ivorensis), and Iroko (Milicia excelsa). Others include Obeche (Triplochiton scleroxylon), Ofun (Mansonia altissima), Omo (Cordia milleni) and Opepe (Nauclea diderrichii). The physical properties of wood species that were studied include; the grain pattern, texture, colour, vessels (pore) distribution and arrangement, rays, density and specific gravity of the wood species. The wood species were collected from different sawmills in Akure, whose major source was Akure forest reserve and its environment. Observations were carried out and the results obtained were compared with information from past records and research made previously on the selected wood species. The result of the study showed variation in all the properties studied. This result and information obtained on the physical properties of the selected wood species were documented and this could be used as baseline information on identification of the wood species, research work and future referencing. 
Publisher:
 Nigerian Journal Of Forestry
Publication Type:
 Journal
Publication Title:
 Dimensional Stability Of Paper Cement Bonded Ceiling Board Made From Recycled Paper
Publication Authors:
 Owoyemi J.M. And Ogunrinde O.S.
Year Published:
 2013
Abstract:
The effect of mixing ratio and paper blending proportion on paper cement bonded ceiling boards’ dimensional stability was investigated using water absorption and thickness swelling tests at 24, 48 and 72 hours of soaking. These boards were made from 100% old Newsprint paper, blend of Newsprint and Kraft paper at 50:50 and 100% Kraft paper mixed at cement/ paper ratios of 1:1, 2:1 and 3:1 and CaCl2 additive concentration of 3%. The variation in the blending proportion and mixing ratio affected the density and dimensional stability of the boards. Boards of higher mixing ratio and density absorbed less water than those of low mixing ratio because higher cement content and resultant higher density determined the moisture intake of the boards. The results showed that there was difference in water absorption at the different hours but there were no changes in thickness swelling after 48 and 2 hours soaking. The highest level of water absorption and thickness swelling were recorded at the lowest mixing ratio of 1:1 and 100% blending of Newsprint alone. It was observed that water absorption and thickness swelling reduced with increase in mixing ratio and blending proportion. The results further revealed that boards made from 100% Kraft paper were dimensionally stable and addition of Kraft paper to Newsprint at 50:50 ratio improved dimensional stability. This made the boards durable and suitable for use where ceiling board is prone to shrinkage and in an environment of high humidity which cause swelling panel products. 
Publisher:
 ProLigno International Journal In The Field Of Wood Engineering
Publication Type:
 Journal
Publication Title:
 Effect Of Density On The Natural Resistance Of Ten Selected Nigerian Wood Species Subterranean Termites’ Attack
Publication Authors:
 Owoyemi, J.M., Olaniran, O.S., And Aliyu D.
Year Published:
 2013
Abstract:
The effect of density on the natural resistance of selected Nigerian wood species to subterranean termites was investigated. Wood samples obtained from mixedconversion boards were used such that the samples contained both sapwood and the heartwood. They were sawn to 35x35x450mm stake and dried at 103±2°C till a constant weight was achieved. Density of the selected wood species was determined. Based on the observed average density, the wood species were classified into high, medium or low density. Graveyard test method was used to assess the natural resistance of the samples on a site dominated by Macrotermes sybhylinus, a family of subterranean termites. Weekly visual observations of the stake were taken as specified in ASTM D334580 Standards for 24 weeks. The wood samples were withdrawn at the 24th weeks of exposure to termites and weight loss due to termites’ attack was estimated. Result obtained showed the relationship between wood density, weight loss and the ASTM ratings. A strong but negative correlation (R2 = 0.70) existed between weight loss and wood density while as strong positive correlation (R2 = 0.83) existed between ASTM values and wood density. These results indicated that wood species in the high density class had a better resistance to termite’s attack. The influence of mixed conversion on the resistance of wood species to subterranean termites was also reported, since it is the most common method of conversion in the Nigerian sawmills. The sapwood of high density species are not durable as revealed in the study thus the preservative treatment is imperative for long service life.