Norwahyuni Mohd Yuosf

Mrs. Norwahyuni Mohd Yuosf


Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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19 January 2023 in Forests
Verified
Journal Article
Open access
PDF file
NYNorwahyuni Mohd Yuosf
Norwahyuni Mohd Yuosf
Seng Hua LeeSeng Hua Lee
Seng Hua Lee
PTParidah Md Tahir
Paridah Md Tahir
RJRedzuan Mohammad Suffian James
Redzuan Mohammad Suffian James
Syeed SaifulAzry Osman Al EdrusSyeed SaifulAzry Osman Al Edrus
Syeed SaifulAzry Osman Al Edrus
RRRoman Reh
Roman Reh
Bamboo requires treatment to extend its service life. However, as bamboo strips could serve as a suitable candidate for lamination, the treatment may affect its bendability. The current study investigated the effects of boric acid treatment on the physical, mechanical, adhesion, and morphological properties of bamboo strips. Owing to their availability and popularity in local industries, four Malaysian bamboo species were used in this study, namely Gigantochloa scortechinii, Gigantochloa levis, Dendrocalamus asper, and Bambusa vulgaris. These four species’ bamboo strips were treated with 5% boric acid and their properties were evaluated. The findings revealed that the boric acid treatment had varying degrees of effect on the properties of the bamboo. Despite having lower treatability and stability, both G. scortechinii and G. levis have greatly superior mechanical properties that justify their use in the production of laminated products. The boric acid treatment was found to provide several benefits to bamboo strips intended for lamination, including increased wettability, dimensional stability, and mechanical strength.

23 February 2023 in Forests
Verified
Journal Article
Open access
PDF file
NYNorwahyuni Mohd Yuosf
Norwahyuni Mohd Yuosf
PTParidah Md Tahir
Paridah Md Tahir
Seng Hua LeeSeng Hua Lee
Seng Hua Lee
MUMohd Khairun Anwar Uyup
Mohd Khairun Anwar Uyup
RJRedzuan Mohammad Suffian James
Redzuan Mohammad Suffian James
Muhammad Adly Rahandi LubisMuhammad Adly Rahandi Lubis
Muhammad Adly Rahandi Lubis
Semantan (Gigantochloa scortechinii) and beting (Gigantochloa levis) bamboo are the two Malaysian bamboo that are suitable to be converted into laminated bamboo boards. One of the main criteria for laminated board is its good bondability, which is determined by shear performance. The shear performance of laminated board is influenced by several factors such as the species used, adhesive types and lamination configurations. Therefore, in this study, laminated bamboo boards were produced using Semantan and Beting bamboo bonded with phenol–resorcinol–formaldehyde (PRF) and polyurethane (PUR) adhesives. Different configurations (lay-up patterns and strip arrangements) were used during the consolidation of the laminated boards. The bamboo strips were arranged in three different arrangements, namely vertical, horizontal and mixed, and then assembled into a three-layered structure with two lay-up patterns, which are perpendicular and parallel. Shear performances, such as shear strength, bamboo failure and delamination of the boards, were evaluated. The results revealed that the adhesive type and lay-up pattern were the most influential factors on the shear performance. PRF-bonded laminated bamboo boards outperformed PUR-bonded laminated bamboo boards in terms of shear strength and bamboo failure but PUR bonding had better bond durability as indicated by its low delamination. Boards laminated parallelly significantly outperformed those bonded perpendicularly. As for strip arrangement, PRF-bonded laminated boards were less influenced by it compared to PUR-bonded laminated boards. The results suggested that PRF is a better adhesive for bamboo lamination due to its higher shear performance and more consistent performance across structural configurations (lay-up patterns and strip arrangements).

27 August 2022 in Forests
Verified
Journal Article
Open access
PDF file
RASDIANAH DAHALIRASDIANAH DAHALI
RASDIANAH DAHALI
Seng Hua LeeSeng Hua Lee
Seng Hua Lee
PTParidah Md Tahir
Paridah Md Tahir
EBEdi Suhaimi Bakar
Edi Suhaimi Bakar
ARAdlin Sabrina Muhammad Roseley
Adlin Sabrina Muhammad Roseley
RJRedzuan Mohammad Suffian James
Redzuan Mohammad Suffian James
This study assessed the machining properties of 11-year-old Eucalyptus urophylla × E. grandis, known as E. urograndis wood, that was infected by stem canker disease, Chrysoporthe deuterocubensis. Instead of being discarded directly, the study aimed to explore the possibility of infected trees being used in other applications such as furniture. Sawing, planing, and boring properties as well as the surface roughness of the healthy and infected trees were evaluated. The samples were collected from infected and healthy trees and classified according to the severity of the attack: healthy (class 1), moderately infected (class 2), severely infected (class 3), and very severely infected (class 4). Prior to sawing, planing, and boring, the samples were prepared according to ASTM D 1666-11 Standard Test Methods for Conducting Machining Tests of Wood and Wood-Base Materials. All samples were sawn, planed, and bored and were evaluated for their respective machining quality. The surface roughness of the machined samples was also assessed. Overall, E. urograndis of different infection severity has very good machining properties ranging from Grade I to III. Fuzzy grain, chip grain, chip mark, and tear out are the most commonly seen physical defects. As for surface roughness, healthy trees have lower surface roughness compared to that of infected trees, which indicates a better surface quality. The findings of this study suggested that infected E. urograndis can still be used in many applications. The results of this study will provide us with better knowledge about the machining performance of disease-infected E. urograndis wood and its possibilities to be used as raw material for the wood products industry.