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... Since cellulose is a primary target of fungal degradation, and is abundant in wood, higher cellulose content could correlate with greater susceptibility. These findings agree with Ogunjobi et al. (2014) who demonstrated the role of cellulose degradation in fungalinduced wood decay. Strong positive correlations were observed between moisture content, absorption, and retention (r > 0.88), indicating that more moisture facilitates better absorption and retention of the bio-preservative. ...
... product. Additionally, thin cell walls of Enset fiber positively influence the flexibility, burst strength, and tensile strength of the paper (Lemma et al. 2016;Ogunjobi, Adetogun, and Omole 2014). The Runkel ratio is also a crucial parameter for assessing the suitability of the raw materials for pulp and paper production. ...
... Thin fiber walls are desirable for dense, well-formed paper, whereas thick-walled fibers result in bulky, coarse-surfaced paper. High Runkel ratio fibers are stiff, less flexible, and form bulkier paper with low bounded areas (Ogunjobi, Adetogun, and Omole 2014). A study by Lemma (2018) found that the Runkel ratio of Enset fiber was 0.7, indicating thin fiber walls suitable for paper production, promoting good sheet binding formation and high pulping quality. ...
Current research and design initiatives are cautiously focused on the use of natural fibers from agricultural waste, as they can generate financial gains, improve crop sustainability, and effectively address environmental issues. In Ethiopia, an estimated 100–million Enset plants are harvested annually for their starchy food, providing 20% of the population. This process generates approximately 150,000 tons of Enset fiber, which researchers are actively investigating as a promising and eco-friendly fiber source. Fibers from the Enset plant have been investigated for their potential use in various applications, particularly as materials for cellulosic nanocrystals, paper, and composites production. However, the potential of Enset fiber remains largely untapped due to the limited understanding of its properties, and the inconsistencies in the data reported by previous studies regarding its chemical, physical, mechanical, and thermal properties. Therefore, it is crucial to organize the data for researchers and manufacturers to make informed decisions regarding future studies and applications of this fiber. This review discusses recent research on the unique properties of Enset fibers, their potential as green composites, and their potential for paper and cellulosic nanocrystals as an alternative to natural fibers. The review also unveils the challenges of Enset fibers in advanced applications and suggests future research avenues.
... Runkel ratio is an important indicator of the suitability of fibre for paper-making (Ogunjobi, et al., 2018). It relates to pulp yield, fibre density and paper conformability (Ogunjobi, et al., 2014: Ogunjobi, et al., 2018. Fibres with a RR less than 1 are good for paper making because the fibres are more flexible, collapse easily and form papers with large bonded areas while those above one are considered thick-walled and stiffer and form bulky paper sheet of lower bonded area (Dutt, et al., 2004;Ogunjobi, et al., 2018). ...
Forest Ecosystems in Nigeria. Opportunity for green economy in 21st century
... An image of the fibre sample is magnified and projected onto a screen, from which the apparent diameter is measured. According to Ogunjobi et al., (2014), analyses revealed that the mean fibre diameter for Vitex doniana is recorded as 21.9 . ...
<Organik Rankine Çevrimleri (ORC); jeotermal, biyokütle, atık ısı ve güneş enerjisi gibi düşük sıcaklıktaki enerji
kaynakları kullanılarak elektrik üretiminde kullanılmaktadır. ORC çevrimlerinde çalışma akışkanı olarak su
yerine organik bileşikler kullanılmaktadır. ORC çevriminde çevresel etkileri azaltmak için düşük küresel ısınma
potansiyeline (GWP) sahip çalışma akışkanlarına ihtiyaç duyulmaktadır. Bu çalışmada ozon delme potansiyeli
(ODP) sıfır ve GWP değeri çok düşük olan, R1234ze(E), R1233zd(E) ve R1234yf çalışma akışkanlarının
kullanıldığı ORC sistemi modellenerek termodinamik analizleri yapılmıştır. Düşük GWP değerine sahip bu
akışkanların kullanıldığı ORC çevriminin performans karşılaştırılması sonucu en uygun çalışma akışkanı
R1233zd(E) belirlenmiştir.
... An image of the fibre sample is magnified and projected onto a screen, from which the apparent diameter is measured. According to Ogunjobi et al., (2014), analyses revealed that the mean fibre diameter for Vitex doniana is recorded as 21.9 . ...
Fosil yakıtların hızla tükenmesi, enerjide dışa bağımlı ülke olmamız yenilenebilir enerji kaynaklarını ülkemiz
için önemli hale getirmektedir. Özellikle rüzgâr enerjisi rüzgâr türbinleri ile direkt enerji üretilebilmesi yönünden
dikkat çekmektedir. Ancak rüzgâr türbinlerinin maliyetinin yüksek olması bölgeye ait rüzgâr hız tahminlerinin
doğruya en yakın ve en az maliyetle yapılmasını gerektirmektedir. Bu çalışmada Afyon ilinin meteorolojiden
alınan 2015-2018 yıllarına ait sıcaklık, hava basıncı, bağıl nem, güneş radyasyonu verileriyle rüzgâr hızı tahmin
edilmiştir. Bu amaçla veri madenciliği yönteminde farklı modeller kullanılmıştır. En düşük ortalama mutlak hata
(MAE) değeri 0.092 ve kök ortalama kare hata (RMSE) değeri 0.122 ile en yüksek determinasyon katsayısı (R2
)
değeri 0.8557, SMOreg modeli kullanılarak elde edilmiştir. Sonuç olarak veri madenciliği yönteminin rüzgâr hız
tahmininde başarıyla kullanılabileceği görülmüştür.
... It is expected that the study species wood will produce poor paper unless mixed with those of soft-wood or recycled paper pulps. Fiber slenderness ratio significantly influenced the breaking length, bursting, tearing and stretch of the pulp sheets (Ogunjobi et al., 2014). The studied species fibers were of good slenderness ratios (117.76), ...
Acacia seyal var. seyal is considered as one of the widely distributed tree species in Sudan particularly in the poor rural area; nevertheless rural populations are not benefiting much from its wood. Acacia seyal's uses concentrate in charcoal, firewood and fuel wood due to the lack of information on its wood properties. Despite the richness of Sudan in most of basic factors required to establish forest based industries it still almost entirely dependent on imports to satisfy its needs of the products of such industries like pulp and paper, fibreboard etc. There is an urgent need to evaluate the available local raw materials as potential sources for forest bases industries. This would not only reduce imports, but it would also promote rural development and alleviate poverty and improve livelihoods of local communities. The present study was carried out to investigate the wood properties of Acacia seyal var. seyal and assess its suitability for flooring, pulp and paper industries. This species is widely distributed and easily grow all over Sudan and under different soil types and ecological zones. The wood materials were collected from different zones in Sudan. Some anatomical, physical and mechanical properties were investigated and their results were used to consider the suitability of the selected tree species for flooring, pulp and paper industries. In anatomical investigations, Fiber characteristics were evaluated. Concerning physical and mechanical investigations, wood density and hardness strength were determined respectively. The overall anatomical, mechanical and physical investigations of the studied species indicate its suitability for flooring, pulp and paper industries. This will enhance the establishment of wood industry in undeveloped rural areas where ever the wood raw materials and the water supply are available. Such development will help in the poverty elimination and leads to rural people welfare.
... In both sapwood and heartwood samples, cell wall thickness of fibers was irregularly increased with increasing SH. Ogunjobi et al. (2014) aimed to analyze longitudinal variations in the fiber properties of Vitex doniana (Sweet). They found that fiber length at butt, 10%, 50%, and 90% height levels of the tree was 1.50 mm, 1.64 mm, 1.48 mm, and 1.43 mm, respectively. ...
Sapwood, heartwood, mature wood, juvenile wood, top wood, base
wood, compression wood, tension wood, stem wood, and branch wood have
different fiber properties. One of the most significant influences on the use
of wood as a final product is its fiber properties. The small diameter woods
at the top position of a tree has generally been used as firewood due to their
low economic value. However, these tree parts can be converted into high-value-added products such as pulp and paper. Therefore, this review gives
a detailed summary of fiber morphology differences throughout the stem
height (SH) of various tree species.
... It is expected that the study species wood will produce poor paper unless mixed with those of soft-wood or recycled paper pulps. Fiber slenderness ratio significantly influenced the breaking length, bursting, tearing and stretch of the pulp sheets (Ogunjobi et al., 2014). The studied species fibers were of good slenderness ratios (117.76), ...
Acacia seyal var. seyal is considered as one of the widely distributed tree species in Sudan particularly in the poor rural area; nevertheless rural populations are not benefiting much from its wood. Acacia seyal's uses concentrate in charcoal, firewood and fuel wood due to the lack of information on its wood properties. Despite the richness of Sudan in most of basic factors required to establish forest based industries it still almost entirely dependent on imports to satisfy its needs of the products of such industries like pulp and paper, fibreboard etc. There is an urgent need to evaluate the available local raw materials as potential sources for forest bases industries. This would not only reduce imports, but it would also promote rural development and alleviate poverty and improve livelihoods of local communities. The present study was carried out to investigate the wood properties of Acacia seyal var. seyal and assess its suitability for flooring, pulp and paper industries. This species is widely distributed and easily grow all over Sudan and under different soil types and ecological zones. The wood materials were collected from different zones in Sudan. Some anatomical, physical and mechanical properties were investigated and their results were used to consider the suitability of the selected tree species for flooring, pulp and paper industries. In anatomical investigations, Fiber characteristics were evaluated. Concerning physical and mechanical investigations, wood density and hardness strength were determined respectively. The overall anatomical, mechanical and physical investigations of the studied species indicate its suitability for flooring, pulp and paper industries. This will enhance the establishment of wood industry in undeveloped rural areas where ever the wood raw materials and the water supply are available. Such development will help in the poverty elimination and leads to rural people welfare.
... The morphology of the fibres is important index in evaluating the suitability of fibre for pulp and paper-making Dinwoodie (1965). A number of hardwood species have been studied by various researchers (Ogunwusi, 2002;Osadare, 2001;Ogunkunle & Oladele, 2008;Oluwadare, & Sotannde, 2007;Ogunjobi, Adetogun, & Omole, 2014) were reported to be suitable sources of fibre for paper making. Although the suitability rating by these authors was based only on the fibre lengths of the species. ...
... Rigid fibres do not have efficient elasticity and are not suitable for paper production except for cardboard production (Akgül and Tozluoğlu, 2009). It is expected that pulp made from all the wood species would have a greater inter-fibre bond and hence greater tensile strength, which favours those properties that affect printing (Ogunjobi et al., 2014). This range is almost similar to Brindha, Vinodhini & Alarmelumangai (2012), where 0.60 (60%) was reported as well as similar for some and higher than some Nigerian Guinea Savannah Timbers (Sadiku and Abdukareem, 2019). ...
... Fibre slenderness significantly influenced the pulp sheets breaking length, bursting, tearing and stretching (Ogunjobi et al., 2014). All the species had good Slenderness Ratio as they all pass the SR > 33 acceptable value for paper-making fibre according to Xu et al., (2006). ...
To find a lasting solution to the problem of suitable fibre for pulp and papermaking in Nigeria, fibre suitability indices of nineteen wood species native to the rainforest zone of Nigeria were evaluated. Matured stems of the species were sourced and prepared for maceration. The fibre characteristics of the wood were carried out following ASTM D-1030-95 and ASTM D-1413-61. The fibres obtained were observed with the aid of a microscope and measurements of their morphology were done. A minimum of 25 fibres were measured for each species for accuracy. Selected morphological indices such as Runkel Ratio (RR), Flexibility Coefficient (FC), Slenderness Ratio (SR) as well as Rigidity Coefficient (RC) of the wood fibres were estimated. The results showed that the fibres lenght fall under short (1.05–1.36), medium-long (1.52–1.75), and long (2.0 mm) fibres criteria. All derived morphological indices showed significant variations from species to species. All fibres are not rigid and exhibited good SR with moderate rigidity and good felting power. They were all elastic; R. heudolotii and P. macrocarpa exhibited high elastic nature. They all have FC ≥ 50 and pass the RR ≤ 1, acceptable value for paper-making fibre except P. biglobosa and M. excelsa. The flexibility coefficients are in the range of 0.50 and 0.81. All the species pass the SR > 33 acceptable value for paper-making fibres. The species if harnessed as fibre blends in pulp and paper making furnish will help to solve the problem of inadequate long fibres for paper production in Nigerian pulp mills.
... The morphology of the fibres is important index in evaluating the suitability of fibre for pulp and paper-making Dinwoodie (1965). A number of hardwood species have been studied by various researchers (Ogunwusi, 2002;Osadare, 2001;Ogunkunle & Oladele, 2008;Oluwadare, & Sotannde, 2007;Ogunjobi, Adetogun, & Omole, 2014) were reported to be suitable sources of fibre for paper making. Although the suitability rating by these authors was based only on the fibre lengths of the species. ...
... Rigid fibres do not have efficient elasticity and are not suitable for paper production except for cardboard production (Akgül and Tozluoğlu, 2009). It is expected that pulp made from all the wood species would have a greater inter-fibre bond and hence greater tensile strength, which favours those properties that affect printing (Ogunjobi et al., 2014). This range is almost similar to Brindha, Vinodhini & Alarmelumangai (2012), where 0.60 (60%) was reported as well as similar for some and higher than some Nigerian Guinea Savannah Timbers (Sadiku and Abdukareem, 2019). ...
... Fibre slenderness significantly influenced the pulp sheets breaking length, bursting, tearing and stretching (Ogunjobi et al., 2014). All the species had good Slenderness Ratio as they all pass the SR > 33 acceptable value for paper-making fibre according to Xu et al., (2006). ...
To find a lasting solution to the problem of suitable fibre for pulp and papermaking in Nigeria, fibre suitability indices of nineteen wood species native to the rainforest zone of Nigeria were evaluated. Matured stems of the species were sourced and prepared for maceration. The fibre characteristics of the wood were carried out following ASTM D-1030-95 and ASTM D-1413-61. The fibres obtained were observed with the aid of a microscope and measurements of their morphology were done. A minimum of 25 fibres were measured for each species for accuracy. Selected morphological indices such as Runkel Ratio (RR), Flexibility Coefficient (FC), Slenderness Ratio (SR) as well as Rigidity Coefficient (RC) of the wood fibres were estimated. The results showed that the fibres lenght fall under short (1.05–1.36), medium-long (1.52–1.75), and long (2.0 mm) fibres criteria. All derived morphological indices showed significant variations from species to species. All fibres are not rigid and exhibited good SR with moderate rigidity and good felting power. They were all elastic; R. heudolotii and P. macrocarpa exhibited high elastic nature. They all have FC ≥ 50 and pass the RR ≤ 1, acceptable value for paper-making fibre except P. biglobosa and M. excelsa. The flexibility coefficients are in the range of 0.50 and 0.81. All the species pass the SR >33 acceptable value for paper-making fibres. The species if harnessed as fibre blends in pulp and paper making furnish will help to solve the problem of inadequate long fibres for paper production in Nigerian pulp mills.
