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Fulltext Biodegradable Gloves for Waste Management Post-COVID-19 Outbreak: A Shelf-Life Prediction

Ab Rahman MF, Rusli A, Misman MA, Rashid AA

ACS Omega, 2020 Nov 24;5(46):30329-30335.
PMID: 33251468 DOI: 10.1021/acsomega.0c04964

With increased awareness on the importance of gloves arising from the COVID-19 pandemic, people are expected to continue using them even after the pandemic recedes. This scenario in a way increased the rubber solid waste disposal problem; therefore, the production of biodegradable gloves may be an option to overcome this problem. However, the need to study the shelf life of biodegradable gloves is crucial before commercialization. There are well-established models to address the failure properties of gloves as stated in the American Society for Testing and Material (ASTM) D7160. In this study, polysaccharide-based material-filled natural rubber latex (PFNRL) gloves, which are biodegradable gloves, were subjected to an accelerated aging process at different temperatures of 50-80 °C for 1-120 days. Prediction models based on Arrhenius and shift factors were used to estimate the shelf life of the PFNRL gloves. Based on the results obtained, the estimated time for the PFNRL gloves to retain 75% of their tensile strength at shelf temperature (30 °C) based on Arrhenius and shift factor models was 2.8 years. Verification on the activation energy based on the shift factor model indicated that the shelf life of PFNRL gloves is 2.9 years, which is only a 3.6% difference. The value obtained is aligned with the requirement in accordance with ASTM D7160, which states that only up to a maximum of 3 years' shelf life is allowed for the gloves under accelerated aging conditions.

Matched MeSH terms: Rubber
Pneumatic jigging: Influence of operating parameters on separation efficiency of solid waste materials

Abd Aziz MA, Md Isa K, Ab Rashid R

Waste Manag Res, 2017 Jun;35(6):647-655.
PMID: 28431479 DOI: 10.1177/0734242X17697815

This article aims to provide insights into the factors that contribute to the separation efficiency of solid particles. In this study, a pneumatic jigging technique was used to assess the separation of solid waste materials that consisted of copper, glass and rubber insulator. Several initial experiments were carried out to evaluate the strengths and limitations of the technique. It is found that despite some limitations of the technique, all the samples prepared for the experiments were successfully separated. The follow-up experiments were then carried out to further assess the separation of copper wire and rubber insulator. The effects of air flow and pulse rates on the separation process were examined. The data for these follow-up experiments were analysed using a sink float analysis technique. The analysis shows that the air flow rate was very important in determining the separation efficiency. However, the separation efficiency may be influenced by the type of materials used.

Matched MeSH terms: Rubber
Single-nucleotide polymorphism markers within MVA and MEP pathways among Hevea brasiliensis clones through transcriptomic analysis

Abdul Rahman SN, Bakar MFA, Singham GV, Othman AS

3 Biotech, 2019 Nov;9(11):388.
PMID: 31656726 DOI: 10.1007/s13205-019-1921-3

In this study, RNA sequencing of several Hevea brasiliensis clones grown in Malaysia with different annual rubber production yields and disease resistance was performed on the Illumina platform. A total of 29,862,548 reads were generated, resulting in 101,269 assembled transcripts that were used as the reference transcripts. A similarity search against the non-redundant (nr) protein databases presented 83,771 (83%) positive BLASTx hits. The transcriptome was annotated using gene ontology (GO), the Kyoto Encyclopedia of Genes and Genomes (KEGG) and the Pfam database. A search for putative molecular markers was performed to identify single-nucleotide polymorphisms (SNPs). Overall, 3,210,629 SNPs were detected and a total of 1314 SNPs associated with the genes involved in MVA and MEP pathways were identified. A total of 176 SNP primer pairs were designed from sequences that were related to the MVA and MEP pathways. The transcriptome of RRIM 3001 and RRIM 712 were subjected to pairwise comparison and the results revealed that there were 1262 significantly differentially expressed genes unique to RRIM 3001, 1499 significantly differentially expressed genes unique to RRIM 712 and several genes related to the MVA and MEP pathways such as AACT, HMGS, PMK, MVD, DXS and HDS were included. The results will facilitate the characterization of H. brasiliensis transcriptomes and the development of a new set of molecular markers in the form of SNPs from transcriptome assembly for the genotype identification of various rubber varieties with superior traits in Malaysia.

Matched MeSH terms: Rubber
Effects of Running Surface Stiffness on Three-Segment Foot Kinematics Responses with Different Shod Conditions

Abdul Yamin NAA, Basaruddin KS, Salleh AF, Salim MS, Wan Muhamad WZA

Appl Bionics Biomech, 2021;2021:8842591.
PMID: 33603827 DOI: 10.1155/2021/8842591

Objective: The aim of this study was to investigate the effects of surface stiffness on multisegment foot kinematics and temporal parameters during running.
Methods: Eighteen male subjects ran on three different surfaces (i.e., concrete, artificial grass, and rubber) in both heeled running shoes (HS) and minimal running shoes (MS). Both these shoes had dissimilar sole profiles. The heeled shoes had a higher sole at the heel, a thick base, and arch support, whereas the minimal shoes had a flat base sole. Indeed, the studied biomechanical parameters responded differently in the different footwear during running. Subjects ran in recreational mode speed while 3D foot kinematics (i.e., joint rotation and peak medial longitudinal arch (MLA) angle) were determined using a motion capture system (Qualysis, Gothenburg, Sweden). Information on stance time and plantar fascia strain (PFS) was also collected.
Results: Running on different surface stiffness was found to significantly affect the peak MLA angles and stance times for both HS and MS conditions. However, the results showed that the joint rotation angles were not sensitive to surface stiffness. Also, PFS showed no relationship with surface stiffness, as the results were varied as the surface stiffness was changed.
Conclusion: The surface stiffness significantly contributed towards the effects of peak MLA angle and stance time. These findings may enhance the understanding of biomechanical responses on various running surfaces stiffness in different shoe conditions.

Matched MeSH terms: Rubber
Fulltext General dental practitioners' confidence in performing molar root canal treatment

Abdullah, M., Che Ab Aziz, Z.A., Roslan Saub, Murat, N., Sulaiman, E., Hashim, N., et al.

Ann Dent, 2009;16(1):9-14.
MyJurnal

The objectives of this study were to assess the practice of molar root canal treatment (RCT) among general dental practitioners (GDPs), confidence level of GDPs in performing molar RCT and to identify factors that influence their confidence in managing molar RCI. One hundred questionnaires were distributed to GDPs in Kuala Lumpur and Selangor. Fifty questionnaires were delivered by mail and the remaining fifty were hand-delivered. All data was coded and verified. Fiftysix OOPs rcsponded to the questionnaires. Only fortyfive questionnaires were accepted (n=45) as eleven OOPs had never performed molar RCI. Most of the OOPs followed the standard quality guidelines while performing molar RCT except for vitality testing (36.4%) and rubber dam usage (27.3%). In this study, 100% of the GDPs were confident in making diagnosis of perinidicular diseases and 95.4% were confident in performing molar RCT from history taking until obturation. Patients' tolerance and availability of instruments and materials (97.7%) were two factors that most influence the GDPs' confidence level. The. least influcncing factor was undergraduate training (78.1 %). Attending seminars and lectures on endodontic, large number of molar teeth treated for ReT, patLents' affordability to pay for RCT and postgraduate training also influencc GDPs' confidence to a certain degree. From this study, it can be concluded that majority of OOPs complied standard quality guidelines except for vitality testing and rubber dam usage. Most of them were confident in performing molar RCT and were greatly influenced by the availability or"instruments and materials in their clinic and patients' tolerance in receiving molar RCI.

Matched MeSH terms: Rubber Dams
Fulltext Effect of epoxidized natural rubber on mechanical properties of epoxy reinforced kenaf fibre composites

Abu Bakar, M.A., Ahmad, S., Kuntjoro, W.

Pertanika Journal of Science & Technology, 2012;20(1):129-137.
MyJurnal

Kenaf fibre that is known as Hibiscus cannabinus, L. family Malvaceae is an herbaceous plant that can be grown under a wide range of weather conditions. The uses of kenaf fibres as a reinforcement material in the polymeric matrix have been widely investigated. It is known that epoxy has a disadvantage of brittleness and exhibits low toughness. In this research, liquid epoxidized natural rubber (LENR) was introduced to the epoxy to increase its toughness. Kenaf fibres, with five different fibre loadings of 5%, 10%, 15%, 20% and 25% by weight, were used to reinforce the epoxy resins (with and without addition of epoxidized natural rubber) as the matrices. The flexural strength, flexural modulus and fracture toughness of the rubber toughened epoxy reinforced kenaf fibre composites were investigated. The results showed that the addition of liquid epoxidized natural rubber (LENR) had improved the flexural modulus, flexural strength and fracture toughness by 48%, 30%, and 1.15% respectively at 20% fibre loading. The fractured surfaces of these composites were investigated by using scanning electron microscopic (SEM) technique to determine the interfacial bonding between the matrix and the fibre reinforcement.

Matched MeSH terms: Rubber
Fulltext Seismic response of a base isolated cable-stayed bridge under near-fault ground motion excitations

Ahad Javanmardi, Zainab Ibrahim, Khaled Gheadi, Mohammed Jameel, Usman Hanif, Gordan, Meisam

Scientific Research Journal, 2018;15(1):1-14.
MyJurnal

Nowadays, development of cable-stayed bridges is increasing around the world. The mitigation of seismic forces to these bridges are obligatory to prevent damages or failure of its structural members. Herein, this paper aimed to determine the near-fault ground motion effect on an existing cablestayed bridge equipped with lead-rubber bearing. In this context, Shipshaw cable-stayed bridge is selected as the case study. The selected bridge has a span of 183.2 m composite deck and 43 m height of steel tower. 2D finite element models of the non-isolated and base isolated bridges are modelled by using SAP2000. Three different near-fault ground motions which are Tabas 1978, Cape Mendocino 1992 and Kobe 1995 were subjected to the 2D FEM models in order to determine the seismic behaviour of the bridge. The near-fault ground motions were applied to the bridge in the longitudinal direction. Nonlinear dynamic analysis was performed to determine the dynamic responses of the bridge. Comparison of dynamic response of nonisolated and base isolated bridge under three different near-fault ground motions were conducted. The results obtained from numerical analyses of the bridge showed that the isolation system lengthened the period of bridge and minimised deck displacement, base shear and base moment of the bridge. It is concluded that the isolation system significantly reduced the destructive effects of near-fault ground motions on the bridge.

Matched MeSH terms: Rubber
Effects of kenaf loading and alkaline treatment on properties of kenaf filled natural rubber latex foam

Ahmad Fikri Abdul Karim, Hanafi Ismail, Zulkifli Mohamad Ariff

Sains Malaysiana, 2018;47:2163-2169.

This research was carried out to study the effects of kenaf loading and alkaline treatment on tensile properties, density,
thermal and morphological properties of kenaf filled natural rubber latex foam (NRLF). Samples were prepared using a
Dunlop method. From the results, increasing loading of kenaf reduced the tensile strength and elongation at break for
both samples, treated and untreated kenaf filled NRLF. Meanwhile, modulus at 100% elongation and density increased
with an increased in kenaf loading. Samples with treated kenaf showed higher tensile strength, modulus at 100%
elongation and density but low in elongation at break as compared with samples with untreated kenaf. Thermal study
by using thermogravimetric analysis (TGA) showed that thermal stability reduced with increased in kenaf loading for
both samples. Samples with treated kenaf have higher thermal stability compared with samples of untreated kenaf. The
filler-matrix interaction and the pores size variation of both samples was clearly seen in the micrograph images by using
scanning electron microscope (SEM).

Matched MeSH terms: Rubber
Fulltext Evaluation of cold in-place recycling mix using polymer modified Asphalt emulsion

Ahmad Kamil Arshad, Juraidah Ahmad, Mohd Izzat Asyraf Mohamad Kamal

Pertanika Journal of Science & Technology, 2017;25(107):219-226.
MyJurnal

This paper details a study conducted to evaluate the performance of cold in-place recycling (CIPR) using polymer modified asphalt emulsion (PMAE). The asphalt emulsion was modified using natural rubber latex (NRL). Four proportions of reclaimed asphalt pavement (RAP) which are 0%, 25%, 50% and 75% were mixed with natural aggregates and modified asphalt emulsion using natural rubber latex (NRL). The results showed that the optimum modified asphalt emulsion for each proportion of RAP decreased due to the increase in RAP content. Results obtained from Indirect Tensile Strength (ITS) and Uniaxial Compressive Strength (UCS) test for the mixes complied with the requirements of the Road Engineering Association of Malaysia (REAM) specifications. The unsoaked and soaked ITS values obtained were 0.2 MPa and 0.15 MPa respectively, and the minimum compressive strength of CIPR mix obtained was 0.7 MPa. Based on the evaluation of performance for the four RAP proportions, it was determined that 50% of RAP gave the best combination of the CIPR mixture.

Matched MeSH terms: Rubber
Fulltext Brain activation display functional asymmetry in response to action, background and tonal frequency during a pitch memory processing: an fMRI study

Ahmad Nazlim Yusoff, Khairiah Abdul Hamid, Farah Nabila Ab Rahman, Mazlyfarina Mohamad, Khairiah Abdul Hamid, Siti Zamratol-Mai Sarah Mukari

Jurnal Sains Kesihatan Malaysia, 2018;16(1):35-44.
MyJurnal

In this study, the asymmetry of the main effects of action, background and tonal frequency during a pitch memory processing
were investigated by means of brain activation. Eighteen participants (mean age 27.6 years) were presented with low and
high frequency tones in quiet and in noise. They listen, discriminate and recognize the target tone against the final tone
in a series of four distracting tones. The main effects were studied using the analysis of variance (ANOVA) with action (to
wring (rubber bulb) vs. not to wring), background (in quiet vs. in noise) and frequency (low vs. high) as the factors (and
levels respectively). The main effect of action is in the right pre-central gyrus (PCG), in conformation with its contralateral
behavior. The main effect of background indicated the bilateral primary auditory cortices (PAC) and is right lateralized,
attributable to white noise. The main effect of frequency is also observed in PAC but bilaterally equal and attributable to
low frequency tones. Despite the argument that the temporo-spectral lateralization dichotomy is not especially rigid as
revealed by the main effect of frequency, right lateralization of PAC for the respective main effect of background clearly
demonstrates its functional asymmetry suggesting different perceptual functionality of the right and left PAC.

Matched MeSH terms: Rubber
Fulltext Some remarks on diurnal radon concentration at various locations in Peninsular Malaysia

Ahmad Saat, Zaini Hamzah, Zaharidah Abu Bakar, Zuraidah A. Munir, Siti Mariam Sumari, Misbah Hassan

Journal of Nuclear and Related Technologies, 2010;2010(1):49-57.
MyJurnal

A study was carried out to determine short term diurnal radon concentration at five locations in Malaysia. Two locations (KG & AP) are former tin mining areas that has been converted to housing area and training centre respectively, one a relatively new city (SA), that was formerly a rubber and oil palm plantation area, one older cities (KB) and one housing complex by the sea (LP). The study was carried out in 2005, 2006 and 2007 using a diffused-junction photodiode sensor continuous radon monitor. The monitor is recognized by the USEPA. In each location, measurements were carried out on at least ten sites. Former tin mining areas of KG and AP shows up to seven times higher indoor average than the average in the other three locations. However the indoor average in all locations is still below the action level of 4 pCiL-1. For outdoor, the former tin mining areas average concentration was higher than the global average of 0.4 pCiL-1. For the twenty four hours temporal variation the trend indicated that former tin mining areas concentration are always higher, and at time up to six fold higher. The hourly variation of all locations follows an identical trend of high concentration during early to late morning and drop in the afternoon till evening. The outdoor twenty four hour temporal average of former tin mining areas is consistently higher than the outdoor global average of 0.4 pCiL-1. The strong correlation between indoor and outdoor concentration at AP, indicates that indoor radon might originates from outdoor environment. The study was also extended to estimate the effective dose (mSvyr-1) of Rn-222 to the public.

Matched MeSH terms: Rubber
Fulltext EVALUATION OF SELECTED HERBS EXTRACT AS REPELLENT AGAINST RUBBER TERMITES (Coptotermes curvignathus)

Ahmad Zaimi Mohd Zawawi, Shazatul Izzati Sha’aree

Journal of Academia Universiti Teknologi MARA Negeri Sembilan, 2021;9(1):85-90.
MyJurnal

Termites encompass a various range of destruction of crops and capable of decomposing woods. The widely being used of hazardous chemical pesticides has develop many health problems to the users. Hence, the aim of this study was to substitute the use of hazardous chemical pesticides to herbs based pesticides as repellent agent against rubber termites (Coptotermes curvignathus), which is safer and easier to use. The selected herbs species for this study are lemongrass (Cymbopogon citratus), garlic (Allium sativum) and wild mint (Mentha arvensis). As for C.curvignathus, they were obtained from Forest Research Institute Malaysia (FRIM), Kepong, Selangor, Malaysia. Khaya wood (Khaya senegalensis) (3cm x 2cm x 2cm) is the woods sample that being used. All woods samples were treated with all the selected herbs extract. The repellent testing was conducted for 21 days. The result obtained showed that the three herbs were effective to be used as repellent when compared to percentage weight loss of control, which is 23.58%. The percentages of weight loss of treated groups using aqueous extraction of herbs were 0.61% (lemongrass), 1.56% (mint), and 1.72% (garlic), whereas for methanol extraction of herbs were 0.52% (lemongrass), 1.13% (mint) and 1.55% (garlic). From Analysis of Variance (ANOVA), there is significant different in mean among group with F=275.49, p- value=0.000

Matched MeSH terms: Rubber
Epoxidized natural rubber/polyvinyl chloride/microcrystalline cellulose (ENR/PVC/MCC) composite membrane for palm oil mill effluent (POME) treatment

Aina Aqila Arman Alim, Rizafizah Othaman

Sains Malaysiana, 2018;47:1517-1525.

Epoxidized natural rubber/polyvinyl chloride/microcrystalline cellulose (ENR/PVC/MCC) composite membranes were
prepared and used to treat palm oil mill effluent (POME). The loadings of MCC were varied at 0, 5, 10 and 15 w/w%. The
increment of MCC loads has intensified the hydroxyl peak of the membranes in FTIR spectrum, indicating the increase
in membrane hydrophilicity. MCC acted as a pore forming agent since the ENR/PVC/10% MCC gave the highest water
flux and well-distributed pores. After first treatment of POME, the levels of chemical oxygen demand (COD), biochemical
oxygen demand (BOD) and total suspended solid (TSS) were reduced to 99.9%, 70.3%, and 16.9%, respectively. These
data showed that ENR/PVC/MCC membrane has the potential to treat POME.

Matched MeSH terms: Rubber
Fulltext Phenol removal via cellular immobilization: a review

Aisami Abubakar, Mohd Yunus Shukor

Bioremediation Science and Technology Research, 2017;5(2):1-7.
MyJurnal

Environmental pollution is one of the major concerns in the 21st century; where billions of tonnes
of harmful chemicals are produced by industries such as petroleum, paints, food, rubber, and
plastic. Phenol and its derivatives infiltrate the ecosystems and have become one of the top major
pollutants worldwide. This review covers the major aspects of immobilization of phenoldegrading
bacteria as a method to improve phenol bioremediation. The use of various forms of
immobilization matrices is discussed along with the advantages and disadvantages of each of the
immobilization matrices especially when environmental usage is warranted. To be used as a
bioremediation tool, the immobilized system must not only be effective, but the matrices must be
non-toxic, non-polluting and if possible non-biodegradable. The mechanical, biological and
chemical stability of the system is paramount for long-term activity as well as price is an
important factor when the very large scale is a concern. The system must also be able to tolerate
high concentration of other toxicants especially heavy metals that form as co-contaminants, and
most immobilized systems are geared towards this last aspect as immobilization provides
protection from other contaminants.

Matched MeSH terms: Rubber
Fulltext Engineering characterisation of epoxidized natural rubber-modified hot-mix asphalt

Al-Mansob RA, Ismail A, Yusoff NI, Rahmat RA, Borhan MN, Albrka SI, et al.

PLoS One, 2017;12(2):e0171648.
PMID: 28182724 DOI: 10.1371/journal.pone.0171648

Road distress results in high maintenance costs. However, increased understandings of asphalt behaviour and properties coupled with technological developments have allowed paving technologists to examine the benefits of introducing additives and modifiers. As a result, polymers have become extremely popular as modifiers to improve the performance of the asphalt mix. This study investigates the performance characteristics of epoxidized natural rubber (ENR)-modified hot-mix asphalt. Tests were conducted using ENR-asphalt mixes prepared using the wet process. Mechanical testing on the ENR-asphalt mixes showed that the resilient modulus of the mixes was greatly affected by testing temperature and frequency. On the other hand, although rutting performance decreased at high temperatures because of the increased elasticity of the ENR-asphalt mixes, fatigue performance improved at intermediate temperatures as compared to the base mix. However, durability tests indicated that the ENR-asphalt mixes were slightly susceptible to the presence of moisture. In conclusion, the performance of asphalt pavement can be enhanced by incorporating ENR as a modifier to counter major road distress.

Matched MeSH terms: Rubber/chemistry*
Fulltext Treatment of rubber wastewater using zinc sulphate as coagulants-data collection on removal efficiency for physicochemical and heavy metal parameters

Alkarkhi AFM, Amr SSA, Alqaraghuli WAA, Özdemir Y, Zulkifli M, Mahmud MN

Data Brief, 2021 Feb;34:106685.
PMID: 33409347 DOI: 10.1016/j.dib.2020.106685

This article provides data regarding the performance of zinc sulphate as a coagulant for treating rubber industry wastewater. The effect of four factors on removal efficiency of nine parameters is investigated, namely: pH, mixing speed, dosage of coagulant (zinc sulphate) and retention time. Response surface methodology was used to investigate the effect of selected variables. The data obtained from face centered composite design (FCCD) were analyzed by using analysis of variance (ANOVA) and regression model to find the optimum operating conditions for the selected factors.

Matched MeSH terms: Rubber
Upgrading producer gas quality from rubber wood gasification in a radio frequency tar thermocatalytic treatment reactor

Anis S, Zainal ZA

Bioresour Technol, 2013 Dec;150:328-37.
PMID: 24185417 DOI: 10.1016/j.biortech.2013.10.010

This study focused on improving the producer gas quality using radio frequency (RF) tar thermocatalytic treatment reactor. The producer gas containing tar, particles and water was directly passed at a particular flow rate into the RF reactor at various temperatures for catalytic and thermal treatments. Thermal treatment generates higher heating value of 5.76 MJ Nm(-3) at 1200°C. Catalytic treatments using both dolomite and Y-zeolite provide high tar and particles conversion efficiencies of about 97% on average. The result also showed that light poly-aromatic hydrocarbons especially naphthalene and aromatic compounds particularly benzene and toluene were still found even at higher reaction temperatures. Low energy intensive RF tar thermocatalytic treatment was found to be effective for upgrading the producer gas quality to meet the end user requirements and increasing its energy content.

Matched MeSH terms: Rubber/chemistry*
Surfactants with aromatic headgroups for optimizing properties of graphene/natural rubber latex composites (NRL): Surfactants with aromatic amine polar heads

Ardyani T, Mohamed A, Bakar SA, Sagisaka M, Umetsu Y, Mamat MH, et al.

J Colloid Interface Sci, 2019 Jun 01;545:184-194.
PMID: 30878784 DOI: 10.1016/j.jcis.2019.03.012

HYPOTHESIS: The compatibility of surfactants and graphene surfaces can be improved by increasing the number of aromatic groups in the surfactants. Including aniline in the structure may improve the compatibility between surfactant and graphene further still. Surfactants can be modified by incorporating aromatic groups in the hydrophobic chains or hydrophilic headgroups. Therefore, it is of interest to investigate the effects of employing anilinium based surfactants to disperse graphene nanoplatelets (GNPs) in natural rubber latex (NRL) for the fabrication of electrically conductive nanocomposites.
EXPERIMENTS: New graphene-philic surfactants carrying aromatic moieties in the hydrophilic headgroups and hydrophobic tails were synthesized by swapping the traditional sodium counterion with anilinium. 1H NMR spectroscopy was used to characterize the surfactants. These custom-made surfactants were used to assist the dispersion of GNPs in natural rubber latex matrices for the preparation of conductive nanocomposites. The properties of nanocomposites with the new anilinium surfactants were compared with commercial sodium surfactant sodium dodecylsulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), and the previously synthesized aromatic tri-chain sodium surfactant TC3Ph3 (sodium 1,5-dioxo-1,5-bis(3-phenylpropoxy)-3-((3phenylpropoxy)carbonyl) pentane-2-sulfonate). Structural properties of the nanocomposites were studied using Raman spectroscopy, field emission scanning electron microscopy (FESEM), and high-resolution transmission electron microscopy (HRTEM). Electrical conductivity measurements and Zeta potential measurements were used to assess the relationships between total number of aromatic groups in the surfactant molecular structure and nanocomposite properties. The self-assembly structure of surfactants in aqueous systems and GNP dispersions was assessed using small-angle neutron scattering (SANS).
FINDINGS: Among these different surfactants, the anilinium version of TC3Ph3 namely TC3Ph3-AN (anilinium 1,5-dioxo-1,5-bis(3-phenylpropoxy)-3-((3phenylpropoxy)carbonyl) pentane-2-sulfonate) was shown to be highly efficient for dispersing GNPs in the NRL matrices, increasing electrical conductivity eleven orders of magnitude higher than the neat rubber latex. Comparisons between the sodium and anilinium surfactants show significant differences in the final properties of the nanocomposites. In general, the strategy of increasing the number of surfactant-borne aromatic groups by incorporating anilinium ions in surfactant headgroups appears to be effective.

Matched MeSH terms: Rubber
The distribution of marine debris along the Pahang coastline, Malaysia during the Southwest and Northeast Monsoons

Azman MA, Ramli MZ, Che Othman SF, Shafiee SA

Mar Pollut Bull, 2021 Sep;170:112630.
PMID: 34146861 DOI: 10.1016/j.marpolbul.2021.112630

This study investigated the accumulation of debris at four sites, namely, Gebeng, Batu Hitam, Cherok Paloh, and Air Leleh, along the Pahang coastline, Peninsular Malaysia from March 2019 to February 2020. Plastic was the dominant debris (86.1%) and followed by cloth/fabric-based debris (6.0%), processed lumber debris (3.3%), rubber (2.7%), glass (1.5%), and metal (0.4%). The land-based debris (82.0%) was the major source of the deposition of marine waste. A statistically significant relationship was found between the seasonal variation and marine debris density in tidal and seasonal current along the Pahang coastline. In general, the Northeast Monsoon season had a higher amount of debris than the Southwest Monsoon season.

Matched MeSH terms: Rubber
Fulltext Studies on Leaf Venation in Selected Taxa of the Genus Ficus L. (Moraceae) in Peninsular Malaysia

Badron UH, Talip N, Mohamad AL, Affenddi AE, Juhari AA

Trop Life Sci Res, 2014 Dec;25(2):111-25.
PMID: 27073603 MyJurnal

A study on the variation of leaf venation patterns was conducted on 21 taxa of the genus Ficus in Peninsular Malaysia. The results showed the existence of eight leaf venation patterns based on veinlets, the ultimate marginal and areolar venation. The majority of species, such as F. annulata, F. benghalensis, F. benjamina, F. deltoidea var. angustifolia, F. deltoidea var. kunstleri, F. depressa, F. elastica, F. hispida, F. microcarpa, F. religiosa, F. tinctoria, F. ucinata and F. vasculosa, show tri-veinlets. The others exhibit the following: bi-veinlets in F. aurata and F. heteropleura; uni-veinlets in F. lepicarpa, F. schwarzii and F. superba; and simple veinlets in F. aurantiacea and F. fulva. F. sagittata presents no veinlets for areolar venation. The presence of tracheid or swollen veins at the centre of the lamina and the presence of cystolith cells and trichomes are common anatomical characteristics that could assist in group classification of the studied species. Variations in leaf venation patterns are not only valuable in identifying a taxon group, but can also be used to differentiate between species in the genus Ficus.

Matched MeSH terms: Rubber

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