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Article
Publication date: 1 February 2005

A.H. Basta, H. El‐Saied, R.H. Gobran and M.Z. Sultan

To investigate a new approach for the prevention of lignocellulosic composites based on agro‐fibres (e.g. sugar‐cane bagasse) from the emission of toxic formaldehyde.

883

Abstract

Purpose

To investigate a new approach for the prevention of lignocellulosic composites based on agro‐fibres (e.g. sugar‐cane bagasse) from the emission of toxic formaldehyde.

Design/methodology/approach

Five organic polymer containing nitrogen‐urea formaldehyde (UF) adhesive systems were used as bonding agents for bagasse fibres. The environmental performance of the lignocellulosic composites prepared were evaluated in terms of the effect of the organic polymers on the percentage of free formaldehyde in the adhesive system and the adhesion properties (static bending and water resistance properties) of the composite produced, in comparison with that prepared from un‐modified UF. The nitrogen content of the polymer and the amount of organic polymers incorporated in the adhesive system were optimised using the 3D response surface methodology and the multi‐linear regression technique.

Findings

All investigated organic polymers (crude PAM‐g‐starch, PAM‐g‐starch, PAM, CE‐starch and Cm‐starch) were found to enhance the performance of the UF‐adhesive for producing environmentally friendly bagasse‐composite, whereas the reduction of free‐HCHO in UF‐adhesive systems ranges from 26 to 100 percent. The performance of the composite produced exceeded the ANSI requirements for Grade H‐3 particle‐board.

Research limitations/implications

Despite the success in improving the performance (mechanical properties and reduction of free‐formaldehyde) of the UF‐adhesive and agro‐composites, the polymers needed to be incorporated at a high percentage (12‐20 percent) resulting in reduced water resistance of the product. Further investigation is needed to resolve this problem.

Practical implications

The approach developed provided a simple and practical solution to enhancing the performance of waste agro‐fibres and commercial amino adhesive in the production of high performance lignocellulosic composite.

Originality/value

The organic polymers UF adhesive systems are novel bonding agents for agro‐fibres and could be used in timber mills for production of particle‐board and medium density fibre‐board.

Details

Pigment & Resin Technology, vol. 34 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 4 January 2013

Altaf H. Basta, Houssni El‐Saied and Vivian F. Lotfy

The purpose of this paper is to study the possibility of preparing high performance, agro‐based composites from rice straw, using eco‐polyalcohol polymers‐based adhesive system…

551

Abstract

Purpose

The purpose of this paper is to study the possibility of preparing high performance, agro‐based composites from rice straw, using eco‐polyalcohol polymers‐based adhesive system. The utilization of rice straw (undesirable biowastes) for the production of high quality biocomposite products, will add economic value, help to reduce the environmental impact of waste disposal and, most importantly, provide a potentially inexpensive alternative to the existing commercial artificial wood‐panels.

Design/methodology/approach

Simple synthesizing and optimizing the polyalcohol polymers‐based non‐toxic adhesive system were carried out, by blending corn starch, as natural polyalcohol polymer with polyvinyl alcohol, as synthetic polyalcohol polymers‐based adhesive (St/PV adhesive), at temperature ∼75°C. The percentages of adhesive components, type of starch, bonding temperature and time were optimized. Assessment of the synthesized adhesive was performed from its adhesion behavior (bond strength), in comparison with commercial thermosetting resin (urea‐formaldehyde), as well as the properties (mechanical and physical properties) of the composites produced. The effects of amount and type of water resistance co‐additives (paraffin wax and polyester), on mechanical properties of RS‐based composite were also optimized.

Findings

The promising adhesive system exhibits improved performance over a previously commercially HCHO‐based adhesive (UF), and results bonding strength 9.8 N/mm2, as well as MOR, IB and TS of RS‐based composites up to 31 N/mm2, 0.49 N/mm2 and 20%, respectively.

Research limitations/implications

Through the studied eco‐adhesive with relatively high natural polyalcohol polymer (starch) in presence of water‐resistance additive (PE) provided a good bonding strength and comparative RS‐based composite properties, with that produced from commercial UF. For the mechanical properties (MOR and IB) are complied the standard values; while water resistance is still higher. Further study is needed to solve this problem.

Practical implications

The approach provided a HCHO‐free adhesive with good bonding strength, comparative board strength and water resistance, reasonable working life, and without formaldehyde emission. Starch‐based adhesive with low percentages of polyvinyl alcohol is considered a promising inexpensive alternate adhesive in wood industry based on rice straw wastes, which traditionally required expensive pMDI.

Originality/value

The paper provides a potential way to utilise undesirable rice by‐product (RS), corn starch as industrial raw material. This will benefit farmers significantly. Meanwhile, the modified starch adhesive with low percentage of PVA is promising to partly or completely replace urea formaldehyde resin and pMDI that are mainly used in wood industry, or pMDI in RS‐based artificial wood, avoiding formaldehyde emission or toxic gases during exposed to burning, and reducing the dependence on petroleum products.

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Article
Publication date: 6 March 2017

Altaf Halim Basta, Houssni El-Saied, Amin Mahmoud Baraka and Vivian Fayez Lotfy

The purpose of this research paper focused on studying the role of activated carbons (ACs), which were synthesized from long-chain aldehyde-based xerogels (Xs-AC), as benefit…

204

Abstract

Purpose

The purpose of this research paper focused on studying the role of activated carbons (ACs), which were synthesized from long-chain aldehyde-based xerogels (Xs-AC), as benefit additives to enhance the application of a low-cost urea formaldehyde (UF) adhesive for production of rice straw (RS) composites complying with both the standard specifications of particle-board type and the board produced from using conventional adhesive of RS fibers (methylene diphenyl diisocyanate, MDI). The results are supported by differential scanning calorimetry (DSC) analysis, which indicated the curing and interaction of RS fibers with the adhesive systems.

Design/methodology/approach

RS-based composites of particle-board type were prepared from applying new Xs-AC–UF adhesive systems to RS particles. For comparison, particle boards by using commercial UF and 4 per cent MDI were also prepared. To clear the beneficial effect of X-ACs as new HCHO (formaldehyde)-scavengers, the properties of the resulted boards were compared with those produced from the previous investigated scavenger: amide-containing starch-UF (AM/St–UF), and treated RS. DSC analysis was performed on the RS adhesive system, to follow the curing and the interaction behavior of UF with fibers in the presence of Xs-ACs.

Findings

The promising results obtained of RS particle boards from using the investigated new HCHO-scavenger are modulus of rupture (MOR) = 17.2 MPa, modulus of elasticity (MOE) = 4,689 MPa and internal bond (IB) strength = 0.49 MPa. While, the thickness swelling (TS) and maximum reduction in free-HCHO are 48.5 and 44.6 per cent, respectively; this reduction value specified the particle-board of E1-E2 type.

Research limitations/implications

The X-AC-UF adhesive systems and treated RS provided particle boards with mechanical properties (MOR, MOE and IB) that met the standard specification values (class M-2 according to ANSI standard and P-2 according to EN standard requirements), together with maximum reduction in toxicity of UF. However, the resistance in water swelling property is weak and needs further study to be solved.

Practical implications

The incorporation of small percentage of new HCHO-scavenger (X-AC) to UF is an effective way to improve its thermal behavior. Moreover, the mechanical properties of agro-based composites based on the treated RS waste together with the X-AC-UF system exceeded those values of panels produced from (AM/St-UF) and also from (4 per cent MDI).

Social implications

Incorporating the Xs-AC to commercial UF will be of benefit for saving the health of wood co-workers and motivating the wood mill to export its wood products, as well as minimizing the export of MDI.

Originality/value

This paper was based on enhancing the potential utilization of both undesirable RS agro wastes and environmentally unacceptable low-cost UF adhesive in the production of agro-composites that comply with the International Standard Specifications of particle board type. In this respect, a new HCHO-scavenger was synthesized and applied, based on AC from non-conventional xerogels. This study presents a solution to protect the environment from pollution, as a result of burning the undesirable RS, as well as to protect the workers and users of wood panels from exposure to the toxic and carcinogenic gas (formaldehyde). It also benefits in replacing the high cost of the RS adhesive (MDI) by using low-cost modified UF.

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Article
Publication date: 3 May 2016

Altaf H. Basta, Houssni El-Saied and Emad M. Deffallah

The purpose of this paper is to examine the effects of denaturised rice bran (RB) and route of its incorporation during synthesis of urea-formaldehyde adhesive, on the performance…

95

Abstract

Purpose

The purpose of this paper is to examine the effects of denaturised rice bran (RB) and route of its incorporation during synthesis of urea-formaldehyde adhesive, on the performance of the resulting adhesive, especially viscosity, free-formaldehyde (HCHO) and quality of the produced bagasse-based composites, in comparison with those produced from commercial urea formaldehyde (UF) and RB-added UF.

Design/methodology/approach

The experiments were carried out using different denaturised RB at different percentages (1-5 per cent) and pH’s (9-11 per cent). These denaturised RB were incorporated at the last synthesis stage of UF synthesis process. The assessment was carried out on both the viscosity and environmental safety of the adhesive system, as well as the quality of the manufactured bagasse-based composites, of the particleboards (static bending, internal bond (IB) strength and water resistance properties), in comparison to commercial UF and RB added to UF. The performance of the adhesive system was evidenced by the thermogravimetric analysis and differential scanning calorimetry analyses.

Findings

The results showed that maximum static bending [modulus of rupture (MOR) and modulus of elasticity (MOE)], IB strength and water resistance properties of the resulted wood product accompanied the incorporating 5 per cent of the denaturised RB (pH = 9.0), at the last synthesised stage of UF synthesis process. Where, this synthesis process provided adhesive with viscosity nearly approaching to commercial UF adhesive, and reduced the free-HCHO of adhesive and board by approximately 56 and 49 per cent, respectively. For mechanical and water resistance properties, it provided board with 24.5 MPa MOR, 3,029 MPa MOE, 0.64 MPa IB, 11 per cent swelling (SW) and 20.5 per cent absorption. These properties fulfil the requirements of high grade particleboards American National Standard Institute (ANSI) A208.1, especially with respect to static bending values and water swelling property.

Research limitations/implications

Incorporating 5 per cent of pre-denaturised RB, at pH 9.0, in wet form, and in the last stage of synthesis UF, provided adhesive system with convenient viscosity together with lower free-HCHO and acceptable board properties, compared with that produced from commercial UF, or adding denaturised RB to already synthesised UF. For the mechanical (MOR, MOE and IB) and water resistance properties (SW per cent and absorption per cent) of the produced composite are complied the standard values of H-3 grade of particleboard.

Practical implications

Promising adhesive system is resulted from incorporating 5 per cent of pre-denaturised RB at pH 9.0, in wet form, during last stage of UF synthesis process.

Social implications

Incorporating the RB by-product of oil production to commercial UF or during synthesis of UF will be benefit for saving the healthy of wood co-workers, and motivating the wood mill to export its wood products.

Originality/value

The article provides a potential simple way to solve the drawback of increasing the viscosity of UF, as a result of adding RB, via incorporating the RB during synthesis process. The viscosity of the synthesised RB-modified UF approaches RB-free UF, and consequently the adhesive system easily penetrates through agro-fibres, and provides good bonding behaviour and high performance wood product (both quality and environmental by minimising formaldehyde emission or toxic gasses during board formation).

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Article
Publication date: 1 May 2006

H. El‐Saied and A.H. Basta

To investigate the role of spent sulphite liquor (SSL) retained on neutral sulphite bagasse pulp in the binding action of phenolic resin, for the purpose of enhancing its…

296

Abstract

Purpose

To investigate the role of spent sulphite liquor (SSL) retained on neutral sulphite bagasse pulp in the binding action of phenolic resin, for the purpose of enhancing its performance to produce high quality agro‐based composite.

Design/methodology/approach

Pulps used in this work as agro‐based fibres were prepared from Asplund defibrator and neutral sulphite pulping processes. The performance of the resol resin in presence of SSL, were evaluated in terms of the effects of SSL constituents and using novolac as phenolic resin, in comparison with that prepared from pulps in absence of SSL and conventionally prepared resol – Asplund bagasse composites. Preparation of pulp free from sulphonyl groups and pre‐out‐precipitating the resol or lignosulphonic acid (LSA) on the strength and water resistance properties of the composite produced was also examined. The degraded hemicellulose and LSA in SSL were polynomial correlated with the changes in composites properties.

Findings

All neutral sulphite pulps investigated, in presence of SSL, were found to enhance the strength quality of agro‐based composite compared to commercially available resol‐agro‐based composite. The retained SSL on NS‐raw bagasse pulp could replace the Asplund bagasse pulp together with resol resin in production of agro‐composite. As well as, using neutral sulphite – Asplund bagasse pulp reduced the percent of added resol to half, to produce commercial resol agro‐based composite. The performance of the composite produced from novolac resin‐SSL‐neutral sulphite pulp and resol‐LSA‐neutral sulphite pulp exceeded 1.5 to 1.9 times the strength of commercially available composite.

Research limitations/implications

Despite the SSL retained on pulp success in improving the strength property of the resol resin‐agro‐composites, but it has an undesirable effect on water resistance of the product. This problem was resolved by avoiding the undesirable effect of sulphonyl groups on pulp fibres as well as the degraded hemicellulose in SSL.

Practical implications

The approach developed provided a simple and practical solution to enhancing the performance of phenolic resin as well as agro‐fibres and SSL wastes in the production of high performance lignocellulosic composite.

Originality/value

The resol, together with SSL constituents retained on neutral sulphite pulp, are economic bonding agents for agro‐fibres and could be used in wood mills for production of medium density fibre‐board.

Details

Pigment & Resin Technology, vol. 35 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 July 2014

Altaf H. Basta, Houssni El-Saied and Emad M. Deffallah

The purpose of this paper is to prepare high-performance agro-based composites from the non-toxic rice bran-urea-formaldehyde (RB-UF) adhesive system. Investigations have…

488

Abstract

Purpose

The purpose of this paper is to prepare high-performance agro-based composites from the non-toxic rice bran-urea-formaldehyde (RB-UF) adhesive system. Investigations have continued for production high performance agro-based composites using environmentally acceptable approaches. The utilisation of such system with the available used local agro-based wood products (sugar-cane bagasse, SCB) adds economic value and helps reducing the environmental impact of commercial urea-formaldehyde (UF) adhesive, and most importantly, provides a potentially inexpensive alternative to the existing commercial artificial wood-panel mills.

Design/methodology/approach

Optimising the process for incorporating the RB in UF, as wood adhesive for binding the bagasse fibres, was carried out, by partially replacing commercial UF by denaturalised RB in slurry (wet) and dry form or through synthesis of UF. The denaturalisation of RB was carried out at different pHs (10-11) and at temperature 60°C for two hours. While incorporating the RB during synthesis of UF, it was carried out according to the method reported elsewhere. The formulation of adhesive components, pH value of the denaturalisation stage and the process of incorporating the RB were optimised. Assessment of the role of RB adhesive was specified from its free-formaldehyde (HCHO) content, as well as the properties (mechanical and physical properties) of the produced composites of bagasse particle board type, in comparison with the environmental impact of commercial thermosetting resin (UF).

Findings

The promising adhesive system exhibits improvement in the environmental performance (as E1 type) over a commercially UF adhesive (as E2 type), besides providing boards fulfill the requirements of grade H-3 (according to ANSI A208.1 (NPA1993). This adhesive system was resulted from replacing 30 per cent of UF by denalturalised RB (at pH 10) in slurry form. Where, its reduction in free-HCHO reached 53 per cent, as well as modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB) and TS of the produced boards were approximately 24.2 N/mm2, approximately 3753 N/mm2, approximately 0.84 N/mm2 and approximately 11.4 per cent, respectively.

Research limitations/implications

The eco-adhesive with relatively high percentage of low-cost commercial UF (70 per cent) and 30 per cent RB, as oil production by-product, in slurry form provides good board strength and is environmentally friendly compared to SCB-based composite properties, with that produced from commercial UF. The mechanical (MOR, MOE and IB) and water-resistance properties of the produced composite comply with the standard values.

Practical implications

The approach provided low HCHO-free UF adhesive with good comparative board strength and water resistance and reasonable working life. Replacing 30 per cent of UF by RB in slurry form and denaturalised at pH 10 is considered a promising inexpensive alternate adhesive (as E1) in the wood industry based on SCB wastes.

Social implications

Incorporating the RB by-product of oil production to commercial UF will be beneficial for saving the health of wood co-workers and motivating the wood mill to export its wood products.

Originality/value

It provided a potentially simple way to improve both the utilisation of commercial UF and SCB as industrial substrates for particle-board production. This will benefit farmers, local wood mills in Upper Egypt, significantly. Meanwhile, incorporating low percentage of RB, as oil-mill by-products, is promising to partly replace UF resin in the wood industry, minimising formaldehyde emission or toxic gasses during board formation.

Details

Pigment & Resin Technology, vol. 43 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 October 2002

Alexander Tarakanov and Andrew Adamatzky

An interactive clothing system is one of the basic components of virtual reality. The clothing is implemented via design of two‐dimensional garment panels and putting the panels…

547

Abstract

An interactive clothing system is one of the basic components of virtual reality. The clothing is implemented via design of two‐dimensional garment panels and putting the panels on an actor in a realistic way. We show how to ease this time consuming task by appealing to a hybrid cellular automaton as a parallel computing device. We draw our approach on a fact that the draping fabric bears a feature of natural parallelism. At a very short time scale behavior of any node point of a fabric depends only on the behavior of its closest neighboring node points. Therefore distant regions of the fabric can be simulated independently. Basing on the problem's natural parallelism we design two‐dimensional network of uniform locally connected hybrid automata that execute in parallel a particle model of draping behavior of clothes on a standing mannequin.

Details

Kybernetes, vol. 31 no. 7/8
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 31 March 2020

Ronald Busse, Lothar Winnen, Rafael Wilms and Ralf Lanwehr

Since the dawn of leadership research, generations of scholars have looked at the topic through the lenses of leader personalities and traits, their behaviour, the situation they…

358

Abstract

Purpose

Since the dawn of leadership research, generations of scholars have looked at the topic through the lenses of leader personalities and traits, their behaviour, the situation they are in and their relations with co-workers. Same as with ideology waves in managerial discourse and though sailing under different flags, many of the above “classical” foci reverberate in “modern” organisational literature. The authors argue, however, that relatively little effort has been put into what we label as “organisational embeddedness of leadership” (OEL). The authors here focus on the role of institutionalising leadership within the setting of “poly-contextual” organisational frameworks.

Design/methodology/approach

Addressing the ambiguity of previous OEL research with fresh primary data from Germany, the authors present a clear-cut five-dimensional, 15-items construct. The authors’ empirical validation rests on (1) two independent qualitative studies and (2) three independent quantitative investigations computing exploratory (= 61) and confirmatory (= 172) factor analysis as well as a regression analysis (= 131).

Findings

Structural equation modelling results indicate a single-factor model with five sub-dimensions consisting of leadership training and career development, leadership alignment, evaluation and feedback, implementation of employee interviews and supporting resources for leadership.

Originality/value

This work contributes to a broader understanding of “leadership emergence and development” (LED) from an organisational perspective. The limitations of the present article call for a lively debate on OEL and may illuminate some promising future research avenues.

Details

Leadership & Organization Development Journal, vol. 41 no. 2
Type: Research Article
ISSN: 0143-7739

Keywords

Available. Open Access. Open Access
Article
Publication date: 17 September 2018

Ahmed ElBassoussy

This paper aims to explore the international response to the discovery and development of gas fields in the East Mediterranean basin.

4557

Abstract

Purpose

This paper aims to explore the international response to the discovery and development of gas fields in the East Mediterranean basin.

Design/methodology/approach

The study applies key concepts into a framework and explores the strategies used by nations for developing their influence in the region.

Findings

The key nation states (the USA and Russia) and the supranational EU are notable in their divergent approaches to obtaining access to and influence regarding the gas fields.

Practical implications

The development of the strategies used by the international rivals for access to the resources available from the offshore oil fields is set to be an area for further study.

Originality/value

This paper offers insight into a developing rivalry over energy security, which will a platform for further investigation throughout the exploitation of the “New Gulf” gas fields.

Available. Open Access. Open Access
Article
Publication date: 2 July 2024

Denis Dyvee Errabo, Alicia Dela Rosa and Luis Jose Mari Gonzales

Our study focuses on providing empirical evidence regarding the optimization of podcasting in asynchronous learning. This action research aimed to innovate the delivery of…

1365

Abstract

Purpose

Our study focuses on providing empirical evidence regarding the optimization of podcasting in asynchronous learning. This action research aimed to innovate the delivery of asynchronous classes using differentiated podcasts.

Design/methodology/approach

We utilized action research as the research design for the study. Participating in action research entails developing practical knowledge to improve educational practices through specific methods and critical perspectives (Sáez Bondía and Cortés Gracia, 2022). According to Burns (2007), action research involves deliberate interventions usually prompted by identified issues, mysteries or inquiries that individuals in the social setting seek to improve or change. Implementing changes to enhance individuals' actions and understanding within their context is the focus of action research (Kemmis, 2010). The study’s approach is ideal for examining new practices and gaining enhanced theoretical insights (Altrichter et al., 2002). Engaging in action research helps enhance understanding and empowers us to impact and enhance practices through continuous reflection, exploration and action. Through this iterative process, we can continuously enhance our comprehension and make substantial strides toward fostering positive transformation.

Findings

The study findings showed an apparent rise in student regulation and engagement and remarkable enhancements in learning outcomes, as demonstrated by differences in pre-test and final exam scores. These results highlight the actual effect of specialized podcasts on self-paced inducing students' self-efficacy in learning. Our research provides valuable insights on effectively incorporating podcasts into education, offering innovations and improvement of practice among educators and institutions adapting to the ever-changing landscape of the educational environment while catering to the diverse needs of the learners. This research is pioneering research catering to the various learning styles of asynchronous learning environments.

Research limitations/implications

Although our current sample offered valuable insights, upcoming studies could gain from more extensive and more diverse participant groups to strengthen the reliability of our results and guarantee broader applicability across various demographics and contexts. Moreover, the length of our intervention may have been relatively brief, which could have limited our ability to evaluate the long-term impact of customized podcasts on learning results. Continued investigation into the long-term effects of these interventions could provide valuable insights into their effectiveness over time and help shape the creation of more lasting educational approaches.

Practical implications

Innovation in asynchronous learning differentiated teaching attuned to the diverse learning styles of the students.

Social implications

The study promotes equitable education, which eventually promotes learning outcomes of the students.

Originality/value

We created differentiated podcasts tailored to the learning styles of the students. This research is pioneering research catering to the various learning styles of asynchronous learning environments.

Details

Journal of Research in Innovative Teaching & Learning, vol. 17 no. 2
Type: Research Article
ISSN: 2397-7604

Keywords

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