lnu.sePublications
Change search
Refine search result
1 - 19 of 19
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Alawode, Abiodun
    et al.
    Stellenbosch University, South Africa.
    Eselem-Bungu, Paul
    Stellenbosch University, South Africa.
    Amiandamhen, Stephen
    Stellenbosch University, South Africa.
    Meincken, Martina
    Stellenbosch University, Department of Forest and Wood Science.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    Properties and characteristics of novel formaldehyde-free wood adhesives prepared from Irvingia gabonensis and Irvingia wombolu seed kernel extracts2019In: International Journal of Adhesion and Adhesives, ISSN 0143-7496, E-ISSN 1879-0127, Vol. 95, article id 102423Article in journal (Refereed)
    Abstract [en]

    There is renewed interest in the domestication of Irvingia tree species due to the potential use of various parts of the tree as raw materials for a wide range of applications such as biodiesel production, cosmetics, perfumes, soap, weight-loss supplement etc. The current study investigates the properties of extracts from the seed kernels of two Irvingia species – Irvingia gabonensis (IG) and Irvingia wombolu (IW) as natural wood adhesives. Three extraction methods using various solvent/solute media were compared in terms of yield, composition and mechanical properties. Statistically, the analysis revealed significant differences between the different extraction methods. The adhesion properties of the extracts were tested on wood veneers according to the American Society for Testing and Materials standard (ASTM D – 906-64). The shear strength of the extracts ranged from 0.55 to 1.5 MPa and 0.86 to 1.7 MPa for IG and IW, respectively. The initial decomposition temperature of all Irvingia Kernel extract ranges from 138.3 – 149.11 oC for IG and 129.5 – 145.3 oC for IW. As a result, the hot melt temperature for the adhesive experiments was set around 150 oC. The results indicate that Irvingia kernel extract is a more promising source of non-formaldehyde based adhesives in wood composite production.

  • 2.
    Amiandamhen, Stephen
    University of Benin, Nigeria.
    Technology and market opportunities in fiber cement composites for small scale enterprises in Nigeria2013In: Global Journal of Agricultural Sciences, ISSN 1596-2903, Vol. 12, p. 11-14Article, review/survey (Refereed)
    Abstract [en]

    Solving problems of unemployment and developing new materials for buildings requires moving beyond the traditional approaches to more economical, environmentally benign performance models and design properties. New approaches should develop models based on the literature and a full understanding of the root causes of failure, derived from careful failure analysis. One of the main drivers of the development efforts in fibre based composites is the trend towards greater environmental awareness and the health hazards associated with the utilization of asbestos fibres. The key to effectively developing marketable fibre cement composites for use as building materials that can be used for construction of safe and affordable structures is to identify the research and  development and market needs for such products. This paper looks into the empirical production and market opportunities in terms of product performance accruable to locally manufactured fibre cement ceiling boards.

  • 3.
    Amiandamhen, Stephen
    et al.
    Stellenbosch University, South Africa.
    Izekor, David
    University of Benin, Nigeria.
    Assessment of the physical and mechanical properties of treated Kenaf fibre cement composites2015In: Ife Journal of Technology, ISSN 1115-9782, Vol. 23, no 2, p. 14-17Article in journal (Refereed)
    Abstract [en]

    This study investigated the effect of pretreatment on theproperties of kenaf fibre cement boards. Homogenous fibre cementboards were made from kenaf bast fibres, cement and water. Thefibres were cut into smaller sizes, mixed with cement and water andformed in rectangular moulds. After demoulding, the boards werecured for 28 days. The boards were manufactured at threepretreatment levels which include hot water, 3% CaCl2, hot water and 3% CaCl2 and a control. The fibre cement boards were tested forModulus of Rupture (MOR), Modulus of Elasticity (MOE), InternalBonding (IB), Water Absorption (WA), Thickness Swelling (TS) andLinear Expansion (LE). Also nail ability and withdrawal resistance,termite, fungi and fire resistances were also assessed. The resultsshowed that the mean MOR ranged from 1.31 to 8.25 N/mm2; the meanMOE from 78.0 to 1636.3 N/mm2 for all treated boards. Mean waterabsorption ranged from 27.52% to 67.64% and the mean thicknessswelling from 14.51% to 48.01% for all treated boards. Statisticalanalysis showed that the effects of the pretreatments were significanton the properties evaluated (p < 0.05). The study concluded that hotwater combined with CaCl2 treated boards exhibited the bestmechanical and physical properties.

  • 4.
    Amiandamhen, Stephen
    et al.
    University of Benin, Nigeria.
    Izekor, David
    University of Benin, Nigeria.
    Effect of wood particle geometry and pre-treatments on the strength and sorption properties of cement-bonded particle boards2013In: Journal of Applied and Natural Science, ISSN 0974-9411, Vol. 5, no 2, p. 318-322Article in journal (Refereed)
    Abstract [en]

    The effect of particle geometry and pretreatments on the strength and sorption properties of wood particlecement composite boards was investigated. Wood particles (flakes and sawdust) of Gmelina arborea were mixedwith cement and water in the production of composite boards. The wood particles were pretreated with hot water,calcium chloride and a combination of both treatments to enhance bonding with cement. The slurry was poured intorectangular moulds for board formation. After demoulding, the boards formed were tested for modulus of rupture(MOR), modulus of elasticity (MOE), water absorption (WA) and thickness swelling (TS). The results revealed thatthe mean MOR for flakes boards was 3.23N mm-2 while the mean MOR for sawdust boards was 3.01N mm-2. Hotwater and calcium chloride treatment produced the best effect in flake composite boards with MOR and MOE valuesof 6.90 N/mm2 and 1897.36 N mm-2 while sawdust composite boards had mean MOR and MOE values of 5.69Nmm-2 and 1664.31N mm-2 respectively. The WA rate after 24 hours of flakes and sawdust boards treated with hotwater and calcium chloride was 3.63% and 4.28% while the TS rate was 0.69% and 1.44% respectively. Particlegeometry and pretreatments significantly improved strength and sorption properties of wood particle cementcomposite boards (p<0.05).

  • 5.
    Amiandamhen, Stephen
    et al.
    Stellenbosch University, South Africa.
    Izekor, David
    University of Benin, Nigeria.
    Balogun, Adenike
    University of Benin, Nigeria.
    Performance characteristics of treated kenaf bast fibre reinforced cement composite2016In: Journal of the Indian Academy of Wood Science, ISSN 0972-172X, Vol. 13, no 2, p. 156-160Article in journal (Refereed)
    Abstract [en]

    This study investigated the effect of pretreatment on the properties of kenaf fibre cement boards. Homogenous fibre cement boards were made from kenaf bast fibres, cement and water. The fibres were cut into smaller sizes, mixed with cement and water and formed in rectangular moulds. After demoulding, the boards were cured for 28 days. The fibres were treated at three levels which included hot water, calcium chloride (CaCl2), hot water + CaCl2 and a control (untreated). The fibre cement boards were tested for Modulus of Rupture (MOR), Modulus of Elasticity (MOE), Internal Bond (IB), Water Absorption (WA), Thickness Swelling (TS) and Linear Expansion (LE). The results showed that the mean MOR ranged from 1.31 to 8.25 MPa; the mean MOE from 78.0 to 1636.3 MPa for all treated boards. Mean water absorption ranged from 27.52 to 67.64% and the mean thickness swelling from 14.51 to 48.01% for all treated boards. Statistical analysis showed that the effect of the pretreatment was significant on the properties evaluated (p < 0.05). The study concluded that boards produced from hot water combined with CaCl2 treated fibres exhibited the best mechanical and physical properties.

  • 6.
    Amiandamhen, Stephen
    et al.
    Stellenbosch University, South Africa.
    Meincken, Martina
    Stellenbosch University, South Africa.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    Calcium phosphate bonded wood and fiber composite panels: production and optimization of panel properties2017In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 71, no 9, p. 725-732Article in journal (Refereed)
    Abstract [en]

    The development of phosphate bonded composites with properties comparable with those of current Portland cement bonded products has been investigated. More precisely, the focus of the study was the optimization of calcium phosphate cements in combination with wood processing residues slash pine (Pinus elliottii Engelm.) planer shavings, Black wattle (Acacia mearnsii De Wild.) residues, Blue gum (Eucalyptus globulus Labill.) residues, hemp (Cannabis Sativa L.) hurds and dried crushed sugarcane bagasse (Saccharum officinarum L.) as well as pulp mill sludge and waste paper. A central composite design (CCD) for the response surface methodology (RSM) was applied for selection of the proper parameters. Mechanical tests were conducted on the composite products and the effect of the processing variables was evaluated based on the Pareto analysis of variance. The density of the wood-based panels ranged from 0.68 to 1.21 g cm−3, that of the agricultural fibers from 0.59 to 1.15 g cm−3 and that of the paper pulp panels from 0.81 to 1.21 g cm−3. The modulus of elasticity (MOE) data of the panels ranged from 1.63 to 4.92 MPa for wood, from 0.37 to 3.28 MPa for agricultural fibers and from 0.65 to 3.87 MPa for paper-pulp-based fibers. The physical properties of the composite products met the requirements for Portland-cement-bonded particleboards (EN 634-2, 2007).

  • 7.
    Amiandamhen, Stephen
    et al.
    Stellenbosch University, South Africa.
    Meincken, Martina
    Stellenbosch University, South Africa.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    Effect of bark on the physical and mechanical properties of phosphate bonded wood composites of black wattle (Acacia mearnsii De Wild)2016In: Forest resource and Products: Moving toward a sustainable future, 59th International Convention of the Society of Wood Science and Technology, Curitiba, Brazil, March 6 -10, 2016 / [ed] Susan LeVan-Green, Curitiba, Brazil, 2016, p. 165-173Conference paper (Refereed)
  • 8.
    Amiandamhen, Stephen
    et al.
    Stellenbosch University, South Arica.
    Meincken, Martina
    Stellenbosch University, South Africa.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    Magnesium based phosphate cement binder for composite panels: A response surface methodology for optimisation of processing variables in boards produced from agricultural and wood processing industrial residues2016In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 94, p. 746-754Article in journal (Refereed)
    Abstract [en]

    This study investigates the potential use of magnesium based phosphate cement prepared from a heavy magnesium oxide and monopotassium phosphate as a binder for the production of composite panels using bio-based industrial residues such as bagasse, hemp hurds, pine sawdust, paper mill sludge and wastepaper as raw materials. These residues were used to produce light-weight and durable materials that can compare with current Portland cement based products. The phosphate binder is fast setting, cold curing and has a low carbon footprint compared to its Portland cement counterpart. The development of phosphate bonded board products promises to reduce the energy requirements in the manufacturing process of board products, and also provides an alternative route for disposal or value addition to bio-based residues by developing environmentally friendly products. The board manufacturing process was laid out on a central composite design (CCD) to model the response variable, utilizing as much residues as technically feasible. The design allowed for the production of low and medium density boards that can be used for non-structural interior finishes and partition boards. Response surface methodology (RSM) was used to show the relationships between the production variables and predict the board property by variable optimisation. Tests of mechanical and physical properties were conducted on the boards. The density of hemp boards ranged from 0.59–0.83 g/cm3, bagasse boards ranged from 0.54–0.78 g/cm3, pine boards ranged from 0.58–0.84 g/cm3, paper sludge boards ranged from 0.68–0.81 g/cm3 and wastepaper boards ranged from 0.67–0.81 g/cm3. The study has shown that it is feasible to produce phosphate based board products using bio based industrial and agricultural residues. The physical properties of the products met the minimum requirements for cement bonded particleboard (EN 634:2007) and LD-1 grade particle board (ANSI 208.1:1999).

  • 9.
    Amiandamhen, Stephen
    et al.
    Stellenbosch University, South Africa.
    Meincken, Martina
    Stellenbosch University, South Africa.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    Phosphate bonded natural fibre composites2017In: Forest Sector Innovations for a Greener Future, June 12-16, 2017, Vancouver, Canada: International Union of Forest Research Organizations , 2017Conference paper (Refereed)
    Abstract [en]

    The demands for wood based composites along with increasing economic and environmental concerns on conventional wood products necessitate moving beyond the traditional processing methods to more costeffectiveand environmentally friendly approaches. In the wake of a fast-setting phosphate binder with a low carbon footprint, this study investigates the potential of different waste residues incorporated in formulated magnesium and calcium phosphate binders to produce commercially-viable composite products. The residues include forest waste from alien invasive trees, agricultural processing waste such as bagasse and hemp hurds, and wood-based industrial residues including papermill sludge, waste paper and sawmill waste. A wide range of composite products were produced that met the requirements of Portland cement particleboard (EN 634: 2007). This study presents the result of the process optimization and test conducted to product technical specifications. The development of phosphate bonded natural fibre composites utilizing lignocellulosic residues promises to bring economic potential to developing countries.

  • 10.
    Amiandamhen, Stephen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Stellenbosch University, South Africa .
    Meincken, Martina
    Stellenbosch University, South Africa.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    Phosphate bonded natural fibre composites: a state of the art assessment2019In: Applied Sciences, ISSN 2523-3963, no 1, article id 910Article, review/survey (Refereed)
    Abstract [en]

    Over the last few decades, innovative wood composite products and processes have created markets for new and existing products. Inorganic bonded fibre composites have been developed for high performance applications using conventional cement and concrete. The demands for wood based composites along with increasing economic and environmental concerns on conventional wood products necessitate moving beyond the traditional processing methods to more cost-effective and environmentally friendly approaches. In the wake of the twenty-first century, a fast-setting phosphate binder with a low carbon footprint was developed, which can alternatively be utilized in wood composite development. This paper reviews the recent progress in phosphate bonded composite products, based on published literature from the last two decades. A brief background on Portland cement based natural fibre composites is presented. In addition, the mechanism of the formulation of phosphate binders, the effect of aggregates in the materials and the environmental benefits accruable to such materials are discussed.

  • 11.
    Amiandamhen, Stephen
    et al.
    Stellenbosch University, South Africa.
    Meincken, Martina
    Stellenbosch University, South Africa.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    The effect of chemical treatments of natural fibres on the properties of phosphate‑bonded composite products2018In: Wood Science and Technology, ISSN 0043-7719, E-ISSN 1432-5225, Vol. 52, no 3, p. 653-675Article in journal (Refereed)
    Abstract [en]

    Phosphate-bonded composites are an emerging class of building materials produced from natural fibres and phosphate based cement pastes. They are durable and possess mechanical properties similar to those of Portland cement. However, the moisture absorption of natural fibre can lead to swelling which may result in the reduction in the mechanical strength properties and eventually negatively affect the long-term performance and dimensional stability of the products. This study was aimed at the modification of some properties of selected biomaterial residues in order to enhance the final properties of the phosphate-bonded composite product. Three different treatments were evaluated viz. 1% caustic alkali, 1% acetic anhydride and hot water on natural fibres derived from slash pine, black wattle and bagasse. The effect of the treatment on the fibres was evaluated via HPLC, SEM and FTIR. Further, the performance of the treated fibres was evaluated in composite panels bonded with magnesium phosphate (MgPO4) and calcium phosphate (CaPO4) cement pastes against the controls. The manufactured panels were tested for flexural properties and dimensional stability. In the MgPO4-bonded panels, the MOR increased from 0.55 MPa for untreated bagasse panels to 0.79 MPa for alkalised panels. Similarly, the MOE increased from 150.04 MPa for untreated bagasse panels to 175.65 MPa for alkalised panels. In untreated MgPO4-bonded panels, the mean density was 0.76, 078 and 0.75 g/cm3, while in alkalised panels, the mean density was 0.81, 0.81 and 0.81 g/cm3 for wattle, pine and bagasse panels, respectively. In the bagasse panels, the water absorption was 54.61% for untreated, 48.74% for hot water extracted, 42.21% for acetylated and 36.44% for alkalised MgPO4-bonded panels. This represents a percentage improvement of 11, 23 and 33%, respectively. Alkali-treated fibres had the best effect overall for all measured properties.

  • 12.
    Amiandamhen, Stephen
    et al.
    Stellenbosch University, South Africa.
    Montecuccoli, Zeno
    Stellenbosch University, South Africa.
    Meincken, Martina
    Stellenbosch University, South Africa.
    Barbu, Marius
    Stellenbosch University, South Africa.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    Phosphate bonded wood composite products from invasive Acacia trees occurring on the Cape Coastal plains of South Africa2018In: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 76, no 2, p. 437-444Article in journal (Refereed)
    Abstract [en]

    The feasibility of manufacturing phosphatebonded wood composite board products from four locallyoccurring invasive acacia tree species (Acacia cyclops, A.saligna, A. mearnsii and A. longifolia) was studied usinga formulated magnesium oxide (MgO) and monopotassiumphosphate (KH2PO4) binder system. The optimizationfor the manufacturing process was studied using a centralcomposite statistical design, whereupon the following factorswere considered, i.e. KH2PO4:MgO ratio, the fly ashcontent as partial replacement for the binder and the woodcontent as a ratio of wood to the total inorganic content.A fitted response surface plot was used to show the effectof the main factors and their interactions on the measuredboard properties. A response surface model was developedto predict the parameters leading to the best board properties.All physical properties evaluated met or exceededthe minimum requirements for low density particleboards.The results showed that the variables considered have significanteffects on the physical properties of the boards.The optimum composite manufacturing process for makingdurable products within the scope of the studied specieswas found to be a KH2PO4/MgO ratio of 1.66, an ashcontent of 2.7% and a wood/inorganic ratio of 0.96 for theselected wood species.

  • 13.
    Foti, Dafni
    et al.
    Aristotle Univ Thessaloniki, Greece.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Voulgaridou, Eleni
    Aristotle Univ Thessaloniki, Greece.
    Voulgaridis, Elias
    Aristotle Univ Thessaloniki, Greece.
    Passialis, Costas
    Aristotle Univ Thessaloniki, Greece.
    Amiandamhen, Stephen
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Daniel, Geoffrey
    Swedish University of Agricultural Sciences, Sweden.
    Microstructure and compressive strength of gypsum-bonded composites with papers, paperboards and Tetra Pak recycled materials2019In: Journal of Wood Science, ISSN 1435-0211, E-ISSN 1611-4663, Vol. 65, no 1, p. 1-8, article id 42Article in journal (Refereed)
    Abstract [en]

    The incorporation of recycled papers, paperboards and Tetra Pak as filling materials in brittle matrices presents aninteresting approach in the utilization of waste materials for building construction. This paper examines the compressivestrength and microstructure of gypsum-bonded wastepaper-based composites. Recycled wastepaper of varioustypes (office paper, magazine paper and newspaper), cardboards, paper boxes and Tetra Pak were shredded to shortlength strips of about 4 × 18 mm. The shredded materials were used as filling materials in natural gypsum in a ratioof 1:3 (v/v), and water was added to the mix. The paste was formed in cylindrical samples measuring 10 cm in lengthand 5 cm in diameter. Seven different types of composites were produced depending on the material used. Thecomposite products with newspaper and magazine paper had significantly lower density and compressive strength(p < 0.05) than the others. However, the differences were small to have any practical importance. The density valuesranged between 1.26 and 1.34 g/cm3, and compressive strength was the lowest (4.48 N/mm2) in the gypsum–magazinepaper composites and the highest (6.46 N/mm2) in the gypsum–Tetra Pak I composites. Since the samplesproduced in this study exhibited adequate compressive strength, the products could be suitable for such applicationsas interior walls in building constructions. Scanning electron microscopy (SEM) examination of the fractured surfacesrevealed needle-like structures of gypsite crystals surrounding the fibers, which indicates good adhesion between thehydrophobic matrix and lignocellulosic fibers.

  • 14.
    Izekor, David
    et al.
    University of Benin, Nigeria.
    Amiandamhen, Stephen
    University of Benin, Department of Forestry and Wildlife Management.
    Combustion properties of briquettes produced from sawdust of three different indigenous wood species2013In: Journal of Agriculture and Environment, Vol. 9, no 1 & 2, p. 107-111Article in journal (Refereed)
  • 15.
    Izekor, David
    et al.
    University of Benin, Nigeria.
    Amiandamhen, Stephen
    University of Benin, Nigeria.
    Comparative analysis on the trends in the volume of logs supplied to sawmills in Edo State, Nigeria2011In: Journal of the Nigerian Society for Experimental Biology, ISSN 1595-6938, Vol. 11, no 3, p. 257-263Article in journal (Refereed)
  • 16.
    Izekor, David
    et al.
    University of Benin, Department of Forestry and Wildlife Management.
    Amiandamhen, Stephen
    University of Benin, Department of Forestry and Wildlife Management.
    Utilization of fuelwood as household energy among residents of Benin metropolis, Edo State, Nigeria2017In: Nigerian Journal of Agriculture, Food and Environment, ISSN 0331-0787, Vol. 13, no 2, p. 174-178Article in journal (Refereed)
    Abstract [en]

    The study evaluates the utilization of fuelwood as household energy among residents in Benin metropolis. Its utilization andavailability as household energy source as well as reasons for its preference to other household energy sources was assessed.A random sampling technique was used to select 10 communities within the study area namely; Uselu, Siluko, Uwelu, Ogbaarea, Airport road, Ekehuan, Evbotubu, Aduwawa - Urora quarters, Upper sakponba The survey was carried out in theseareas with the aid of a semi-structured questionnaire administered to respondents who utilize and sell fuelwood in thesecommunities. A total of 200 copies of questionnaire were administered. The main variables measured were those of fuel woodconsumption, availability and sources of fuelwood utilization. The results showed that the 50% of the respondents utilizedfuelwood as their source of domestic house hold energy. 51% of the respondents sourced their fuelwood from fuelwoodvendors while 25% source for fuelwood from their local farmland. 60% of the respondents in the study area spent an averageof N200 daily on fuelwood while 52% of the respondents have a weekly expense of above N700 on fuel wood utilization. Theaverage weekly consumption of fuelwood by 50% of the respondents was between 22 – 27 kg. Hevea braziliensis representing33% of fuelwood species was the most abundant fuelwood consumed by residents in the study araea. The results from T-testand Pearson correlation showed that there was a significant difference in the amount of fuelwood consumed in the differentcommunities within the study area. Therefore the quantity of fuelwood consumed is related to the number of persons perhousehold.

  • 17.
    Izekor, David
    et al.
    University of Benin, Nigeria.
    Amiandamhen, Stephen
    University of Benin, Nigeria.
    Agbarhoaga, Stephen
    University of Benin, Nigeria.
    Effects of geometric particle sizes of wood flour on strength and dimensional properties of wood plastic composites2013In: Journal of Applied and Natural Science, ISSN 0974-9411, Vol. 5, no 1, p. 194-199Article in journal (Refereed)
    Abstract [en]

    The effect of different wood flour sizes on strength and dimensional properties of wood-plastic compositeswere examined. Wood flour of different particle sizes viz; 1.00mm, 2.00mm and >2.00mm were compounded withrecycled low-density polyethylene (LDPE) at different wood/plastic ratio of 1: 1, 2: 3 and 3: 2. The results obtainedshowed that wood flour size > 2.00mm has the highest MOR and MOE values of 1.206N mm-2 and 2484.72Nmm-2while wood flour size of 1.00mm had the lowest MOR and MOE values of 0.505Nmm-2 and 2195.89Nmm-2 respectively.Also the results of the physical properties showed that wood flour size of 1.00mm had the lowest thickness swellingpercentage with mean values of 0.28% and 2.08% while water absorption percentage has mean values of 0.91%and 10.58% after 2 hours and 24 hours of water immersion respectively. It was observed that wood flour size of2.00mm and particle size >2.00mm had the highest thickness swelling and water absorption percentages. Thisshowed that strength properties of wood plastic composites increased with increased particle sizes whereas itsdimensional properties increased with decreased particle sizes. The results of analysis of variance carried out onmechanical and physical properties showed that particle sizes and wood/plastic ratio had a significant effect on themechanical and physical properties of wood plastic composites (p 0.05).

  • 18.
    Izekor, David
    et al.
    University of Benin, Nigeria.
    Amiandamhen, Stephen
    University of Benin, Nigeria.
    Awenagbiku, E
    University of Benin, Nigeria.
    Effect of taper and sawing methods on log conversion among selected sawmills in Edo State, Nigeria2016In: Nigerian Journal of Forestry, Vol. 46, no 1-2, p. 1-6Article in journal (Refereed)
    Abstract [en]

    This study was carried out to determine the effect of taper and sawing methods on log conversion among selected sawmills in Egor andOvia-North East Local Government Areas of Edo State. Ten representative sawmills and thirty round logs were sampled for eachspecies making a total of 300 logs based on the relative abundance of available timber species were sampled. The diameter of the logs,length and girth at small and large ends were measured before conversion. The data were analyzed using descriptive statistics. Theresults obtained showed that Egor Local Government Area has the highest frequency of the selected species representing 56% of totallogs sampled while Ovia North-East Local Government Area has 44% of total logs sampled. Conversion efficiency varied from 56.49to 76.26%. Factors such as inherent defect in the timber, age of the machine and the severity of the log taper affected conversionefficiency at the sawmills. Lumber recovery efficiency increases with bigger log, short log length and narrower taper. Therefore, logsize, taper and log length have positive relationship on lumber recovery efficiency.

  • 19.
    Owofadeju, Femi
    et al.
    University of Ibadan, Nigeria.
    Amiandamhen, Stephen
    University of Benin, Nigeria.
    Effect of enzymatic treatments on strength properties of unbleached Kenaf bast pulp2013In: Bioscience Research Journal, ISSN 0795-8072, Vol. 25, no 2, p. 97-102Article in journal (Refereed)
    Abstract [en]

    Kenaf bast fibres were obtained from the Institute of Agricultural Research and Training (IAR & T), MoorPlantation, Ibadan. The fibres were washed with fresh water, air dried and cut into smaller pieces of 3-5cm long for ease ofpulping. These were cooked for 55 minutes at 170oC in a single batch of a digester. The pulp obtained was washed, oven-driedand soaked in distilled water and beaten at three levels of 900, 1800 and 4800 revolutions respectively. The pulp was treated withMultifect-B, an enzymatic mixture of glucanases and xylanases for 30, 60 and 120 minutes prior to handsheet making. Tear andBurst index were calculated from the resulting handsheets. The results showed that the tear strength decreased from 7.6 mN.m2/gat initial to 6.3 mN.m2/g at 120 minutes of enzyme contact for unbeaten pulp, while pulp beaten at 900 revolutions exhibitedhighest decrease in tear strength from 9.2 mN.m2/g at initial to 5.6 mN.m2/g at 120 minutes, representing a 40% decrease. Forpulp beaten at 1800 revolutions, the burst index increased from 3.1 kPa.m2/g for untreated to 3.4 kPa.m2/g at 60 minutestreatment time and decreased sharply to 2.8 kPa.m2/g at 120 minutes. However, there was no significant difference in the tearindex with the levels of beating (p < 0.05). It was concluded that enzymatic hydrolysis significantly improved burst index whileonly affecting the tear index.

1 - 19 of 19
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf