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Soil respiration plays a crucial role in the worldwide carbon cycle and displays great sensitivity to shifts in soil temperature and moisture levels. Accurate prediction of soil respiration under different ratios of food waste compost (FWC) amended soil in various variables requires a clear understanding of the processes involved. This research introduces an appropriate model aimed at estimating soil respiration. This paper employed three distinct regression models: multiple linear (Model 1), first-order polynomial (Model 2), and second-order polynomial (Model 3). These models were employed to predict soil respiration by assessing its relationship with various factors. The study examined several factors, including FWC amended ratio (A), pH (B), electrical conductivity (EC) (C), organic matter (OM) (D), carbon-to-nitrogen ratio (C/N) (E), moisture content (F), porosity (G), and microbial count (H). These factors were considered potential influencers of the CO2 efflux response. It was observed that A,B,C and E exhibited p-values below 0.05 signifying their significance in the context of the study. Among the regression models, Model 3 demonstrated the lowest mean squared error of prediction (MSEP) and root mean square error (RMSE), 1.142 % and 0.153, respectively. The suitability of Model 3 for predicting soil respiration was attributed to its capacity to account for interaction effects among independent variables. Conversely, the results indicated that a non-linear model provide a better understanding of soil respiration under different ratios of FWC amended soil due to the smallest MSEP and RMSE, suggesting that the predictive model for CO2 efflux aligned more with second-order behaviour.

Rose tea is an aromatic herbal drink made from rose flowers’ fragrant petals and buds (after being dried). There are many beneficial components in rose tea, such as vitamin C, polyphenols, vitamin A, myrcene, quercetin, and other antioxidants. Although dried rose petal tea provides good benefits, there could be some potential for heavy metals, and mould contamination can occur during growth and storage. Heavy metal contamination may occur due to the absorption of these components through fertilizers during the growth process. Exposure of dried rose petals to humid conditions at room temperature from 5 d to 30 d caused mould contamination. In this research, the rose petals are characterized to investigate the existence of heavy metals from different farming methods: organic and inorganic fertilizer. Besides, the effect of shelf life on fungi or microorganism formation is also being studied. In this research work, the samples of rose plants were collected from two different locations using different types of fertilizer (organic and inorganic fertilizer). The samples undergo a pre-treatment process which comprised cleaning and drying roses. The analysis of heavy metal content was conducted using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS) equipment. This study used qualitative approaches to investigate any physical changes of colour and appearance on the dried rose petals samples for every 10 d in 6 weeks duration of time. The current studies suggest that there could be a possibility that the content of copper (Cu) at 203.71 ppb and potassium (K) (162725.23ppb) components have reduced the chance of the dried rose petals being exposed to mould infection and have better resistance against any contamination during the storage period. In food application, this finding is valuable as to provide a longer shelf-life span for the rose tea during storage time. However, it is important to ensure the content was still within the permissible limit for food according to the required standard.

The ability of soil to promote plant development is mostly governed by its hydraulic properties, namely its water retention capacity. Sandy soils are the least fertile because of their poor moisture capacity, high water permeability, and low nutrient concentration. Adding food waste (FW) compost to sandy soil can improve its water retention capacity. The FW compost can enhance soil organic matter, which improves water and nutrient retention in sandy soils for plant growth and health. This study aims to identify the best composition amendment for FW compost to enhance soil water retention in sandy soil (sand 76 %, silt 8 %, clay 10 %, pH 4.8, and EC 142.4 dS/m). Indigenous microorganisms (IMOs) collected from bamboo leaves (Gigantochloa albociliata) were added to the FW compost to supply nutrients and stimulate plant growth. Five treatments were applied experimentally, with FW compost amendment rates of (5,15, 25, 35 and 100) % w/w, compared to unamended sandy soil as the control. 100 % FW compost provided the largest increase (169 %) in the amount of readily accessible water in sandy soil, raised total porosity to 6 % and reduced bulk density by 64 %. The FW compost with 25 % w/w compost significantly increased the seed germination of Dwarf Pak Choy (Brassica campestris sp. chinensis) to 125 %. This short-term study highlights the benefits of using FW compost and its potential to improve water retention when a low amendment rate (25%) is used.

Polylactic acid (PLA) is one of the biodegradable polymer that is widely used in many applications to replace petroleum-based polymer. Despite the advantages of PLA, its disadvantages such as poor toughness and brittleness restrict the usage of PLA. The purpose of this study is to improve the properties of PLA by blending with liquid epoxidized natural rubber (LENR) and graphene oxide (GO). Two different samples were prepared which were PLA/LENR/GO and PLA/GO grafted LENR (PLA/GO-g-LENR) composites. GO-g-LENR was prepared by using grafting method. The materials were blended by using Brabender internal mixer with rotor speed of 60 rpm at 160 °C. The GO content was varied from 1, 3 and 5 phr while the composition of LENR was fixed at 10 wt%. After blending, the compound was compressed into a plate under hot pressing machine then was cut according to ASTM D256 for characterization. The properties of the composites were investigated in term of mechanical, thermal and morphological aspects. Fourier transform infrared (FTIR) analysis was used to confirm the efficiency of grafting method. The addition of 1 phr GO using GO-g-LENR into PLA composite showed the highest impact strength which is 96.02 J/m while 1 phr GO without grafting increased the impact strength from 86.05 J/m to 91.42 J/m. Thermal analysis study by TGA indicated that addition of GO into the composite system has improved its thermal stability. Morphological study revealed that 1 phr GO has better dispersion in PLA/LENR matrix compared to 3 phr GO.

The use of adhesives marks a new epoch in the structure-joining technology as using polymeric material is more sustainable, lower possible curing temperature, fine pitch capability and lightweight as compared to tin-lead soldering. In this study, the optimization of process parameters such as curing time and Liquid epoxidized natural rubber (LENR) loading was carried out using central composite design (CCD) in response to surface methodology (RSM) to determine the optimum condition for achieving maximum adhesive properties (shear strength and peel strength) of epoxy/liquid epoxidized natural rubber (LENR) blend. Analysis of variance (ANOVA) analysis shows that the coefficient of determination for both shear and peel strength models were 0.9838 and 0.9909 indicating a high correlation between the actual values and predicted values. The optimum conditions for a maximum predicted shear strength value of 8.37 MPa was 20.65 parts per hundred rubber (phr) liquid rubber (LR) loading for 6.94 curing days and for a maximum predicted peel strength value of 500 J/m was 18.44 phr for 3.75 curing days. This study reports under optimized conditions, it showed the potential of LENR as one of the most effective ways to improve the adhesive properties of epoxy resin.

The purpose of this review is to describe the utilisation of natural rubber and its modified form in adhesive applications. Adhesive can be defined as material that capable of joining two or more surfaces permanently by the adhesion process. Recently, natural rubber has gaining great interest in the adhesive application in comparison to its counter parts synthetic rubber due to environmental reason as well as good mechanical and thermal properties. In this review, the adhesive properties along with mechanical and thermal properties of the natural rubber are reviewed. The recent advances in the modified natural rubber such as epoxidized natural rubber, liquid natural rubber, telechelic natural rubber and other modified natural rubber are also included and highlighted.

Tomato crop production is currently threatened by a calcium deficient disease called blossom-end rot. To enhance the nutrient intake in the tomato plant, this research explores the potential of soilless media through the enhancement of cation exchange capacity (CEC) and the direct intake of calcium through a foliar application. Zeolite and rice husk ash (RHA) have great potential to enhance the CEC of a media. The foliar method is applied to ensure that the fruits have a sufficient amount of calcium to combat blossom-end rot. The aims of this research are to determine the effect of different soilless media formulation on plant growth and yield of tomatoes (Solanum lycopersicum), and also to determine whether the foliar application can help prevent blossom-end rot disease. Different ratio media formulations of coco peat mixed with zeolite (Z5, Z10, and Z15) and coco peat mixed with RHA (R30, R50, and R100) were evaluated and compared with 100 % coco peat as control. The foliar was applied using 50 ppm chitosan in liquid form for tomatoes planted using the R30 and R50 media. After transplantation, they were sprayed once a week starting from Week 4 until Week 10. Each type of media formulation and a foliar application was planted with 10 tomato plants that were supplied with 1.9 dS/m nutrient solutions.

Hydroxyl terminated liquid epoxidized natural rubber (HTLENR) was successfully synthesized via oxidative degradation of liquid epoxidized natural rubber (LENR) in the presence of cobalt (II) acetyl acetonate (CAA) as the oxidizing agent. The effect of reaction time on molecular weight, chemical structures and hydroxyl content of HTLENR were investigated. The weight average molecular weight (Mw) and polydispersity index (PDI) of the prepared HTLENR were determined using gel permeation chromatography (GPC). The result shows that as the reaction time increased, the Mw decreased indicating the occurrence of higher chain scission. It was found that the lowest Mw was achieved at 10 h reaction time where the Mw and Mn were 37,545 g/mol and 3,233 g/mol. The structural analysis and hydroxyl content of HTLENR on the other hand, were studied by using fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR). The presence of OH group was confirmed by FTIR analysis with the appearance of broad peak at 3,200 - 3,600 cm-1. Subsequently, NMR analysis also confirmed that the highest amount of hydroxyl content which is 7.56 % was achieved at the longest reaction time which is 10 h.

The degradation of epoxidized natural rubber (ENR-50) and liquid epoxidized natural rubber (LENR) was done via oxidative degradation method for the production of hydroxyl terminated epoxidized natural rubber (HTENR) and hydroxyl terminated liquid epoxidized natural rubber (HTLENR) has been analysed. Cobalt (II) acetylacetonate (CAA) were used as an oxidizing agent for chain scission reaction at temperature 60 C in the presence of ethanol. The reaction temperature was fixed at 60 C meanwhile reaction time and the amount of CAA were varied according to the reaction formulation. The HTENR and HTLENR obtained have been characterized using Gel Permeation Chromatography (GPC), Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR). GPC were used to determine the molecular weight before and after the oxidative degradation of respected HTENR and HTLENR were compared with ENR-50 and LENR. The lowest Mn and Mw of HTLENR that were obtained from the oxidative degradation method were found to be 5,163 g/mol and 58,087 g/mol. The appearances of OH end groups were verified by FTIR and NMR analyses to validate the position of each OH functional groups. FTIR analysis confirmed that HTENR and HTLENR contained OH group with the appearance of a broad peak around 3,400 cm-1 to 3,550 cm-1 after the reaction. The presence of OH end groups was verified by NMR analysis with the appearance at 3.39 ppm and 3.66 ppm, corresponding to methylene proton adjacent to hydroxyl group in HOCH2CH2CH2 and methane proton adjacent to OH group in CH2CH2CH(OH)CH3.

The trend in the practical uses of herbal medicine has gained increasing momentum in recent years. One of the trends includes the use of the andrographolide-containing Andrographis paniculata, which is a herb that is traditionally used as medicine. There are not many studies have investigated the cultivation of this plant. The aim of this study is to develop a standard of procedure for cultivating Andrographis paniculata using the fertigation technique. A total of 6 treatments in 2 growth medium compositions were studied; treatments T1, T3, and T5 in Cocopeat-RHA (70:30) and treatments T2, T4, and T6 in 100 % cocopeat. 3 magnesium compositions of 10 ppm (T1 and T2), 50 ppm (T3 and T4), and 70 ppm (T5 and T6) in nutrient solution were also studied. Treatments T1, T3, and T5 showed the potential for better growth quality with a maximum plant height of 32.51 cm, 32.51 cm, and 31.75 cm. The andrographolide content was comparable with controls 1 and 2 (0.67-0.70 µg/mL). In higher magnesium compositions of the nutrient solution, the dry herb yield of T5 and T6 decreased from 2.4 g to 1.6 g and 2.4 g to 1.2 g. The T3 and T5 treatments exhibited a higher yield than T4 and T6 based on a comparison of dry herb yield. The incorporated fertigation technique showed an on-par quantity of andrographolide yield to that of conventional techniques (0.67-0.70 µg/mL) although it showed an advantage of overcoming the cleanliness problem faced in this study. Hence, the T3 standard of procedure was deemed the best, as it gave better plant growth quality with a maximum plant height of 31.75 cm, a maximum number of leaves (141 total count), a good dry herb yield of 2.2 g, and better andrographolide content 0.7 µg/mL. The fertigation technique incorporated with the combined Cocopeat-RHA medium and 50 ppm magnesium composition in the nutrient solution is suggested for the cultivation of Andrographis paniculata.

Polylactic acid (PLA) is a potential polymer to be used in various applications due to biodegradable and biocompatible characteristics. However, its brittle nature limits the usage of PLA. In order to improve the brittleness of PLA, liquid epoxidized natural rubber (LENR) was incorporated with PLA. The objective of this study is to investigate the effect of LENR as toughening agent on rigid PLA matrix in term of mechanical and thermal properties. Polylactic acid/liquid epoxidized natural rubber (PLA/LENR) blends were prepared by melt blending method using Brabender internal mixer with temperature 160 ?, mixing speed of 60 rpm and molded into test samples by compression molding. The LENR content was varied from 0, 5, 10, 15 and 20 wt%. It was found that the addition of LENR increased the impact strength of PLA.10 wt% of LENR showed the optimum impact strength which was 86.05 J/m. However, tensile strength and tensile modulus decreased slightly with increasing of LENR content. The morphology of PLA/LENR blends showed a good dispersion of LENR on PLA matrix at 10 wt% LENR. The differential scanning calorimeter (DSC) showed a gradual drop in melting temperature (Tm) as well as glass transition temperature (Tg) as LENR content increased.

This study evaluated the performance of tailor-made fertiliser formulated specifically for tomato (Solanum Lycopersicum) using different types of media. The effect of the medium on the growth rate and yield of tomato was investigated. The fertiliser for Solanum Lycopersicum was formulated using a fertigation technique and locally available fertiliser compounds based on the plant requirements. The experimental setup consisted of forty polybags of plants divided equally into two rows labelled R1 and R2, where R1 represents the tailor-made fertiliser while R2 represents the commercial fertiliser (the control). Two sets of media were investigated; a mixture of cocopeat, peat moss, and Rice Husk Ash (RHA) while the second set consisted of a mixture of cocopeat, peat moss, and zeolites. The pH of the medium and the growth rate, yield, and electrical conductivity (EC) of the fertiliser were observed and recorded. Other factors such as pest or disease attacks were observed as well. The findings show that the plants fed with tailor-made fertiliser yielded 64 tomatoes, 13 more tomatoes than the plants fed with commercial fertiliser (51 tomatoes). Meanwhile, the results of the different media show that the plants grown in zeolites gave 83 tomatoes, more than twice the yield of tomatoes grown on RHA (32 tomatoes).

The development and characterization of self-healing polymeric materials are now being considered for engineering applications. This is an emerging and fascinating area of research that could significantly extend the working life and improve the safety of the polymeric components for a broad range of applications. Overviews of various self-healing approaches for polymeric materials are presented in this paper. The approaches used to achieve healing functionality can be divided into three, such as microencapsule, microvascular, and intrinsic based healing system. Microencapsulation is a process of enclosing micron-sized particles of solids, droplets of liquids, or gases in an inert shell, which in turn isolates and protects them from the external environment. Microvascular based healing system can be partitioned in a manner similar to microcapsules base healing system in terms of the design cycle. Microvascular based healing system is known to give a significant improvement and overcome a few limitations present in the microcapsule embedded self-healing membrane design. Intrinsic based healing system is inherently able to restore its integrity which requires an external trigger for the self-healing to take place. This system is less complex than the microcapsule and microvascular based healing system in achieving repair through inherent reversibility of bonding of the matrix polymer. The development of polymers that can repair damage autonomously would be useful to improve the lifetime of polymeric materials. Success in the design of self-healing materials has important consequences on the material safety, product performance and enhanced fatigue lifetime.

Bio-nanocomposites based on poly (lactic acid)/epoxidized natural rubber (PLA/ENR) blends containing graphene (G) nanofiller were prepared by melt compounding using nano-single screw extruder with a screw speed of 60 rpm, and followed by compression molding. The ENR and graphene loading was varied from 0-30 wt% and 0.5-2.0 phr. The objectives of this work are to investigate the effect of ENR and graphene loading on PLA matrix on the thermal, morphology and toughness properties. The TGA curve of PLA/ENR and PLA/ENR/G bio-nanocomposites shows a single step of thermal degradation. As increasing the loading of graphene, degradation temperature (Tdeg) was increase where graphene act to slow down the rate of degradation. The PLA/ENR blends showed a co-continuous morphology while PLA/ENR/G bio-nanocomposites revealed a good dispersion of graphene in a PLA/ENR matrix at 1 phr of graphene loading. The optimum impact strength was recorded at 10 wt% of the ENR loading which is 104.6 J/m for the PLA/ENR system. In the case of PLA/ENR/G system, the optimum impact strength was recorded at 1 phr of graphene which is 219.5 J/m. The thermal and toughness enhancement of PLA/ENR/G bio-nanocomposites will diversify the future application of this bio-nanocomposites.

A field experiment was conducted to study the effect of Indigenous Microorganisms (IMO) and rice husk on pH of soilless media and yield of Cucumis sativus (cucumber). Ten polybags were provided for each treatment that consisted of IMO treated media (T1), rice husk treated media (T2), and control media (T3). Every treatment was supplied with 1.9 dS/m EC nutrient solutions and the pH was being measured every two consecutive days until the plants had been harvested. Based on the results, there were significant differences in the pH media and the fruit yield between the treatments. The media containing rice husk had a significant increase in the pH media and was consistent in maintaining the average pH media within the range of 6.6 to 6.7, while fruit yield of cucumber recorded the highest number as compared with the other treatments. The findings had revealed that T2 had resulted in 60 cucumbers (22.66 kg) being harvested, followed by T3 with 45 cucumbers (17.53 kg) and T1 with 45 cucumbers (17.11 kg). It can be safely concluded that the medium containing treated RHA was the best for obtaining high yield of cucumber in soilless media as a local growing media due to the superior of its potential constraint of chemical fertiliser while keeping the stability to continue the growth and fruit production for a long period of time.

Hydroxyl terminated epoxidised natural rubber (HTENR) was synthesised via oxidative degradation method to produce a low molecular weight rubber. Epoxidised natural rubber (ENR) was depolymerised via chemical degradation method using cobalt (II) acetylacetonate (CAA) as the oxidising agent, followed by a treatment with sodium borohydride as a reducing agent to introduce hydroxyl (OH) functional group at both chain ends. The reaction times and the amount of oxidising agent tested were varied from one, three, five and twenty hours and 1to 5 wt% of CAA to obtain the low molecular weight of HTENR. The molecular weight of HTENR was determined using gel permeation chromatography (GPC). The lowest molecular weight of HTENR was achieved at 3 wt% of CAA after 5 h of reaction time at 60 °C where average number (Mn)and average weight (Mw) were 34,000 g/mol and 62,000 g/mol FTIR analysis confirmed that HTENR contained OH groupwith the appearance of a broad peak around 3,200 - 3,600 cm-1 after the reaction. The presence of OH endgroups was verified by NMR analysis with the appearance of two peaks at 3.38 ppm and 3.88 ppm, corresponding to methylene proton adjacent to hydroxyl group in HOCH2CH2CH2 and methane proton adjacent to OH group in CH2CH2CH(OH)CH3.

A series of Low-Carbon Society (LCS) Blueprint has been launched in Iskandar Malaysia (IM) region since 2012. The public must be equipped with fundamental knowledge and skills related to the LCS work conducted collectively through a structured network of like-minded individuals and receive technical support and monitoring from experts and practitioners. This paper presents the lessons learned from a community-based food-waste composting program, a low-carbon action outlined under the IM LCS Blueprint, at Layang-layang, Johor as a case study. Selected volunteers in SC Jaya Sepakat, with the support by Mini Rural Transformation Centre (MRTC) have been trained and were given home composting kits. A centralised composting site was set up where one volunteer has been identified as the key player to manage daily composting operation. Food waste bins were collected and converted into compost through a five-step process at the composting site. A technical advisor from Universiti Teknologi Malaysia transferred the knowledge and technology to the villagers in terms of hands-on training, overall operation, compost quality analysis and post-application study of compost on plants. This study aims to empower the community to implement the food waste composting practices in a sustainable manner that would fulfill the societal and economic needs. The challenges and lessons gained through the 8 months engagement are reported. Post- training and end of project surveys were conducted to assess the performance of the community engagement. The survey concluded that the volunteers require extrinsic motivation from external organisations to continue the LCS initiatives until a tangible economic impact is generated. Community’s daily commitment and limited communication facilities in rural areas made continuous engagement a challenge. The project also drew a lesson of importance in collaboration with different stakeholders for greater impact and optimisation in resources that would require further study.

The goal of this study is to treat pineapple leaves fiber (PALF) with chitosan for antimicrobial properties. The treated PALF with chitosan was then crosslinked with crosslinking agent; butanetetracarboxylic acid (BTCA) to preserve chitosan in the PALF structure. The effectiveness of chitosan and crosslinking agent towards PALF was determined using untreated PALF, PALF treated chitosan, PALF treated chitosan (wash), PALF treated chitosan/BTCA and PALF treated chitosan/BTCA (wash). After the treatment with chitosan and BTCA, the treated PALF undergone the washing process to determine the effectiveness of BTCA to avoid the removal of chitosan from PALF during washing. The presence of chitosan in the PALF was confirmed using Fourier Transform Infra-red (FTIR) analysis. The treated PALF was then characterised in terms of its antimicrobial activity and mechanical properties. Antimicrobial activity test confirmed the presence of chitosan successfully retarded the growth of microbe. Tensile test analysis revealed the untreated PALF has the highest tensile strength compared to all treated PALF. In contrast, young modulus of the treated PALF shows increment relative to the untreated PALF. This study is particularly important for the further application of PALF or other natural fibers especially in medical and textile industry.

The effects of pH on growth rate and yield of Cucumis sativus were determined using different treatment media. In this study, there are 3 different treatments media consists of rice husks ash (T1), Lactobacillus (T2) and blank (T3). Each treatment being supplied with 1.9 dS/m electrical conductivity (EC) of nutrient solutions and the pH was being measured every two consecutive days until 31 d of transplanting. Results showed T1 capable in maintaining the pH media average 6.7 followed by T3 with an average pH value of 6.4 and T1 with pH value of 6.3. Cucumis sativus for treatment of rice husks (T1) recorded the fastest growth rate and highest yield as compared with the other treatments. The total yield obtained was 60 of cucumber (22.66 kg) for T1 followed by T3 with 45 of cucumber (17.53 kg) and T2 with 41 of cucumber (15.92 kg). It can be safely concluded that the medium containing treated rice husk was the best for obtaining high yield of cucumber in soilless media. Rice husks can be a local growing media for crop cultivation due to the ability in maintaining the pH. The right pH media needed to provide the best conditions for most agricultural plants to absorb the nutrients efficiently. The uses of rice husk treatment media shows enhance crop production, maintaining the pH and eventually create more sustainable agriculture and environment.

Agriculture management for better decision making is important due to increased needs for agricultural products and increased pressure on land, water, and other natural resources. Balanced nutrient requirements are essential for increasing tropical crop yield and reducing the risk on the negative environmental impact. Reduce fertiliser consumption and optimise the fertiliser used subjected to waste of fertiliser into the environment are the best way to achieve sustainable agriculture. The nutrient coverage includes macronutrient such as nitrogen (N), phosphorous (P), potassium (K), sulfur (S), magnesium (Mg) and calcium (Ca). In this study, the data and procedures used to set up the model as well as the assumptions made for tropical crops. The main objective of the study is to develop a systematic methodology for fertiliser formulation in fertigation system. The sub-objective of the study is to design fertigation fertiliser formulation by using computer-aided approaches which can minimise the environmental impact by reducing the over-used fertiliser leakage. The methods consist of three steps including data collection, the design of fertiliser formulation and verification of fertiliser formulation. The fertiliser formulation will be formulated by using general optimisation problem as the mixed-integer nonlinear program (MINLP). The results in Stage 1 is expected to be the design formulation of fertiliser sources which gives the minimum cost that is subjected to the plant requirements and the results will further verify in Stage 2. This model-based formulation is the starter for another tropical crop model.