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  1. Fulltext Depression and its relationship to loneliness and life events among urban poor in the federal territory, Kuala Lumpur, Malaysia
    Siti Nor Radhiah Muhammad Y, Nor Ba’yah Abdul K
    Jurnal Psikologi Malaysia, 2016;30:133-141.
    This study examines the relationship between loneliness, life events and depression among 178 adults in the disadvantage community of Malaysia and to determine predictors of depression. A set of standardized questionnaires was used to measure depression, loneliness and stressful life events. The results showed that loneliness and stressful life events were related to depression. Results also showed that loneliness was a predictor of depression. Implications of the study in terms of theory and practice are also discussed.
  2. Social Profiling: A Review, Taxonomy, and Challenges
    Bilal M, Gani A, Lali MIU, Marjani M, Malik N
    Cyberpsychol Behav Soc Netw, 2019 Jul;22(7):433-450.
    PMID: 31074639 DOI: 10.1089/cyber.2018.0670
    Social media has taken an important place in the routine life of people. Every single second, users from all over the world are sharing interests, emotions, and other useful information that leads to the generation of huge volumes of user-generated data. Profiling users by extracting attribute information from social media data has been gaining importance with the increasing user-generated content over social media platforms. Meeting the user's satisfaction level for information collection is becoming more challenging and difficult. This is because of too much noise generated, which affects the process of information collection due to explosively increasing online data. Social profiling is an emerging approach to overcome the challenges faced in meeting user's demands by introducing the concept of personalized search while keeping in consideration user profiles generated using social network data. This study reviews and classifies research inferring users social profile attributes from social media data as individual and group profiling. The existing techniques along with utilized data sources, the limitations, and challenges are highlighted. The prominent approaches adopted include Machine Learning, Ontology, and Fuzzy logic. Social media data from Twitter and Facebook have been used by most of the studies to infer the social attributes of users. The studies show that user social attributes, including age, gender, home location, wellness, emotion, opinion, relation, influence, and so on, still need to be explored. This review gives researchers insights of the current state of literature and challenges for inferring user profile attributes using social media data.
  3. Fulltext Validity and reliability of falls screening mobile application (FallSA) to inform falls risk among Malaysian community dwelling older adults
    Muhammad Iqbal Shaharudin, Devinder Kaur Ajit Singh, Suzana Shahar
    Jurnal Sains Kesihatan Malaysia, 2018;16(101):223-224.
    MyJurnal
    Falls is a global health concern due to its many negative consequences in older adults. Early falls screening and prevention is important among older adults. We developed Falls Screening Mobile Application (FallSA) as a self falls screening tool among older adults. FallSA was developed using data of physical performance test, demographic information and questions to inform falls risk from a larger population based longitudinal study on neuroprotective model for healthy longevity among older adults (LRGS TUA). The aim of this study was to determine validity and reliability of FallSA as a self-screening tool to inform falls risk among Malaysian older adults. This cross sectional study was conducted among 91 community dwelling older adults aged 60 years and above. FallSA was validated against Physiological Profile Assessments (PPA), a comprehensive falls risk assessment tool. Participants used FallSA to test their falls risk by repeating the test twice between an hour. Validity and test–retest reliability of FallSA was examined by using Spearman correlation, Kappa, Sensitivity and Specificity, Intra correlation coefficient (ICC), Cronbach alpha and Bland-Altman. Concurrent validity test was significant with moderate correlation rs = 0.518, p < 0.001, moderate agreement K = 0.516, p < 0.001 and acceptable Sensitivity: 80.4% and Specificity: 71.1%. Reliability of FallSA was shown to be good (ICC: 0.948, CI: 0.921-0.966), good internal consistency α = 0.948, p < 0.001 and good agreement was indicated by small mean differences and narrow limits of agreement (LoA). The results of this study suggest that FallSA was a valid and reliable tool to inform falls risk among Malaysian older adults. Further prospective studies are required to determine the accuracy of FallSA to correctly classify older adults into fallers and non-faller groups.
  4. Microstructural characterization of Au-In thin film deposited by electron beam evaporation
    Norliza Ismail, Muhammad Azmi Abdul Hamid, Azman Jalar
    Sains Malaysiana, 2009;38.
    The microstructure and phase formation of Au-In thin film deposited by e-beam evaporation technique has been studied. Single crystals of rocksalt were used as the substrates. The chamber pressure during deposition was about 2.5 × 10-5 torr and substrate temperature was 35°C. Three types of samples were prepared namely Au, In and Au-In thin films. Microstructure and chemical composition of these thin films were characterized by transmission electron microscopy (TEM) and X-ray photoelectron spectrometer (XPS) respectively. TEM micrograph reveals island structures for both Au and In thin film on the rocksalt substrate, with the In island size distribution is about 9-30 nm compared to Au island in the range of 3-10 nm. The growth of islands instead of smooth film indicates that Au and In thin films follow the Volmer-Weber growth mode. However, island structures were not present on Au-In thin films which most probably follow the Frank van de Merwe growth mode. XPS analysis indicates intermetallic compound was not present in the Au-In thin film suggesting that diffusion process in the interface of Au and In films is minimal.
  5. Rejection of oil emulsion using tubular surface filters
    Cumming IW, Holdich RG, Muhammad Abbas Ahmad Zaini
    Sains Malaysiana, 2013;42:159-166.
    This study was aimed to characterize the rejection of oil emulsion by two tubular surface filters, namely 13 μm slots and 4 μm circular pores. A 17 mm helix was incorporated inside the filters to increase the wall shear stress. Rejection of oil, throughputs and flux decay were measured at varying shear stresses (Rw) and transmembrane pressures (TMP). The results showed that the13 μm slots produced a fairly good oil rejection of 22 μm at Rw=0.26 Pa and TMP=6.9 kPa, while the circular pores gave the rejection of 14.4 μm at Rw=0.21 Pa and TMP=34.5 kPa. The results suggested that the circular pores filter could achieve a better oil retention under lower TMP, while the slots filter could be satisfactorily operated under moderate shear stress and low TMP. The increase of TMP offered poor oil rejection by both filters and this was also true for slots-helix configuration.
  6. Taxonomic diversity of paradise threadfin polynemus paradiseus (Linnaeus, 1758) inhabiting southern coastal rivers in Bangladesh
    Muhammad Abu Bakar Siddik, Md. Reaz Chaklader, Ashfaqun Nahar
    Sains Malaysiana, 2015;44:1241-1248.
    The study was aimed to determine the variation in taxonomic diversity of Polynemus paradiseus based on morphometric and meristic analyses of samples collected from three coastal rivers of Bangladesh (Payra, Tentulia and Kirtonkhola). A total of 105 individuals ranging at 10-20 cm in total length (TL) and 7.91-60.64 g in body weight (BW) were sampled using Been nets and Kachal and Veshal nets. Significant differences were observed in 24 out of 25 morphometric measurements and 6 out of 10 meristic counts among the populations. In morphometric measurements, the first discriminant function (DF1) was accounted for 78.6% and the second discriminant function (DF2) was accounted for 21.4% of among groups variability, explaining 100% of total among group variability. A dendrogram based on morphometric data showed that the Tentulia and Kirtankhola populations showed high degree of overlapping and these two populations were highly different from Payra river population. The canonical graph also showed that the populations of Tentulia and Kirtankhola rivers were more closely related comparing with Payra river population for isometric condition. These findings may provide useful information for the conservation and sustainable management of this important fish.
  7. Mekanisme pembentukan apatit pada permukaan sampel β-wolastonit yang dihasilkan daripada abu sekam padi
    Hamisah Ismail, Roslinda Shamsudin, Muhammad Azmi Abdul Hamid, Rozidawati Awang
    Sains Malaysiana, 2016;45:1779-1785.
    Mekanisme pembentukan apatit pada permukaan β-wolastonit dikaji. β-wolastonit dihasilkan daripada teknik sol-gel menggunakan abu sekam dan batu kapur terkalsin sebagai bahan pemula dengan nisbah CaO:SiO2 adalah 55:45. Kebioaktifan sampel β-wolastonit dikaji dengan merendam sampel berbentuk silinder dalam larutan simulasi badan (SBF) untuk tempoh yang ditetapkan iaitu 1, 3, 7 dan 14 hari. Komposisi permukaan, morfologi dan perubahan struktur sampel sebelum dan selepas direndam dianalisis melalui pembelauan sinar-X (XRD) dan mikroskop elektron imbasan (FESEM) yang digabungkan dengan EDX. Keputusan XRD menunjukkan fasa β-wolastonit berjaya dihasilkan selepas dimasukkan ke dalam autoklaf untuk 8 jam pada suhu 135°C pada tekanan 0.24 MPa dan disinter 2 jam pada suhu 950°C. Apatit didapati tumbuh pada permukaan sampel β-wolastonit selepas 7 hari rendaman dalam larutan SBF. Semasa proses rendaman dalam larutan SBF, 2 jenis kumpulan kalsium fosfat dihasilkan iaitu amorfus kalsium fosfat (ACP) selepas 3 hari rendaman dengan julat nisbah Ca/P 1.2-2.02 dan pada hari ke-14 membentuk hidroskiapatit kurang kalsium (CDHA) dengan nisbah Ca/P 1.63. Perubahan fasa sampel β-wolastonit daripada keadaan hablur kepada amorfus jelas terbukti daripada keputusan XRD selepas direndam dalam SBF dengan penurunan puncak keamatan bagi sampel β-wolastonit pada sudut belauan 30°. Ini mengukuhkan mekanisme pembentukan lapisan apatit pada permukaan sampel β-wolastonit dan ianya bersifat bioaktif.
  8. New hybridization approach of titanium organometallic: PANi thin films as room temperature gas sensors
    Izura Izzuddin, Mohammad Hafizuddin Jumali, Muhammad Yahaya, Muhamad Mat Salleh
    Sains Malaysiana, 2012;41:1017-1021.
    The aim of this research was to investigate the ability of organometallic titanium-PANi hybrid materials as gas sensor at room temperature. To form the hybrid materials, commercially available polyaniline (PANi) powder were directly added into organometallic titanium sols which was synthesized using the sol gel method. The composite films were prepared via spin coating technique followed by electrode deposition for sensors fabrication. Five different organometallic titanium:PANi ratios namely 1 wt% to 5 wt% of PANi were prepared for this experiment. For gas sensing test, all samples were exposed to ethanol vapour. The sensing mode is based on the variation in the electrical conductivity due to the
    interaction between the gas molecules and the film. It was observed that the composite sensors required appropriate ratio to exhibit optimum sensing properties. This finding proved that the hybridization process is successful and offered much cheaper and easier method for fabrication of room temperature gas sensor.
  9. UV-C irradiation affects quality, antioxidant compounds and activity of Musa AAA Berangan
    Phebe Ding, Muhammad Firdaus Rosli, Nur Ayuni Mahassan
    Sains Malaysiana, 2015;44:1095-1101.
    A study to determine the effects of ultraviolet-C (UV-C) irradiation on fruit quality, antioxidant compounds and activities of Musa AAA Berangan was carried out. The mature green fruits were exposed to UV-C doses of 0, 0.01, 0.02, 0.03 and 0.04 kJ/m2 and allowed to ripen at 25±2o C for 5 days. Peel and pulp color, water loss, firmness, soluble solids concentration (SSC), titratable acidity, pH, vitamin C, total phenolic contents (TPC) and antioxidant activity (assay using ferric-reducing antioxidant power (FRAP), 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azinobis-(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) free radical-scavenging) were analyzed at day 0, 1, 3 and 5 after ripening. The peel color (L*, C* and ho) of Berangan banana decreased as UV-C irradiation dose increased. UV-C irradiated fruit has lower water loss, firmer pulp and lower SSC than control. The fruit could undergo normal ripening albeit the quality of fruit has been affected by UV-C irradiation. There was significant interaction between UV-C radiation x day after ripening on TPC of Berangan banana. Fruit irradiated with UV-C showed significant higher of TPC as compared with control at later stage of ripening. Antioxidant activities measured with the three assays showed a significant decrease as ripening progressed. The results of this study showed that UV-C radiation as low as 0.01 kJ/m2 is able to reduce water loss, slow down starch conversion and softening and enhanced TPC of Berangan banana.
  10. Comparing groups using robust H statistic with adaptive trimmed mean
    Nur Faraidah Muhammad Di, Sharipah Soaad Syed Yahaya, Suhaida Abdullah
    Sains Malaysiana, 2014;43:643-648.
    An alternative robust method for testing the equality of central tendency measures was developed by integrating H Statistic with adaptive trimmed mean using hinge estimator, HQ. H Statistic is known for its ability to control Type I error rates and HQ is a robust location estimator. This robust estimator used asymmetric trimming technique, where it trims the tail of the distribution based on the characteristic of that particular distribution. To investigate on the performance (i.e. robustness) of the procedure, some variables were manipulated to create conditions which are known to highlight its strengths and weaknesses. Bootstrap method was used to test the hypothesis. The integration seemed to produce promising robust procedure that is capable of addressing the problem of violations to the assumptions. About 20% trimming is the appropriate amount of trimming for the procedure, where this amount is found to be robust in most conditions. This procedure was also proven to be robust as compared to the parametric (AN0vA) and non parametric (Kruskal-Wallis) methods.
  11. Chemical synthesis of metal nanoparticles in aqueous solutions with the presence of some additives
    Oyama M, Akrajasali Umar, Muhammad M Atsalleh, Burhanuddin Eopmajlis
    Sains Malaysiana, 2011;40:1345-1353.
    Metal nanoparticles having interesting shapes can be prepared in aqueous solutions through simple reductions of metal ions with the presence of some additive reagents, such as cetyltrimethylammonium bromide and hexamethylenetetramine. In this review, some successful results for shape-controlled synthesis of metal nanoparticles in our group are summarized, which includes the synthesis of palladium nanocubes, palladium nanobricks, gold nanotripods. In addition, combining with indium tin oxide electrode surfaces, shape-controlled growth is shown to be possible to form gold nanoplates and copper oxide nanowires. Even in relatively mild synthetic conditions, interesting shape-controlled synthesis of metal nanoparticles is possible.
  12. A qualitative study investigating perceived barriers to medication adherence in chronic illness patients of Karachi, Pakistan
    Naqvi AA, Hassali MA, Aftab MT, Nadir MN
    J Pak Med Assoc, 2019 Feb;69(2):216-223.
    PMID: 30804587
    OBJECTIVE: The study aimed to perceived barriers to medication adherence in patients with chronic illnesses..

    METHODS: A qualitative study was conducted in a tertiary care hospital in Karachi in September 2017, using grounded theory and inductive approach. Interviews were conducted using a checklist in Urdu language from patients of chronic illnesses determined based on medicines dispensed from the out-patient pharmacy in hospital. Interviews were recorded, transcribed verbatim, translated in English and validated. The translated quotations were analysed using a qualitative analysis software, and thematic analysis was conducted. Codes were generated and analysed by semantic linkages and network analysis using ATLAS.ti qualitative research software.

    RESULTS: Of the 16 patients interviewed, 8(50%) were males and 8(50%) were females. Barriers to medication adherence identified were patient behaviour (intentional and un-intentional non-adherence), comorbidity and pill burden, cost-related non-adherence, and low patient knowledge. The last barrier was associated with the rest.

    CONCLUSIONS: Counselling has the potential to increase patient knowledge regarding medication use, and active pharmacist-physician collaboration can improve medication adherence..

  13. Fulltext The effect of burned liver on the length, weight and development of Megaselia Scalaris (loew) (diptera: phoridae) – a preliminary assessment and implications in forensic entomology
    Nur Aqidah Ahmad, Amirah Suhailah Ramli, Raja Muhammad Zuha
    Jurnal Sains Kesihatan Malaysia, 2018;16(1):29-33.
    MyJurnal
    Development of insects in laboratory for minimum post mortem interval estimation (mPMI) or time of colonisation (TOC) in
    forensic entomology can be affected by the type and quality of food consumed during larval period. Since mPMI estimation
    also involves analysis of larval specimens collected from burned human remains, it is important to study if burned tissues
    could affect growth of sarcosaprophagous larvae. This study investigated the effect of burned tissues on the size and
    developmental period of Megaselia scalaris (Loew) (Diptera: Phoridae), a species of forensic importance. Development
    of M. scalaris on 75 g burned cow’s liver was compared with control liver in three study replicates. Mean larval length
    (2.87 ± 0.11 mm) and weight (0.81 ± 0.08 mg) of M. scalaris larvae in burned liver diets were significantly lower than
    larval length (5.03 ± 0.15 mm) and weight (2.85 ± 0.21 mg) of control liver diets (p < 0.001) whilst mean pupal length
    (2.53 ± 0.06 mm) and weight (0.92 ± 0.06 mg) in burned liver diets were significantly lower than pupal length (3.52 ±
    0.06 mm) and weight (2.84 ± 0.16 mg) in control liver diets (p < 0.001). Development of larvae in burned liver was 5-9
    hours slower than those feeding on control liver based on single observation. Although the assessment is preliminary, the
    findings indicate physical growth of larvae feeding on burned animal tissues was affected and entomological specimens
    recovered from burned remains should be evaluated carefully to avoid errors in mPMI/TOC estimation. Limitations and
    suggestions for further research are also presented herein.
  14. Fulltext Estimation of rainfall curve by using functional data analysis and ordinary kriging approach
    Muhammad Fauzee Hamdan, Shariffah Suhaila Syed Jamaludin, Abdul Aziz Jemain
    MATEMATIKA, 2018;34(101):167-177.
    MyJurnal
    Rainfall is an interesting phenomenon to investigate since it is directly related
    to all aspects of life on earth. One of the important studies is to investigate and under-
    stand the rainfall patterns that occur throughout the year. To identify the pattern, it
    requires a rainfall curve to represent daily observation of rainfall received during the year.
    Functional data analysis methods are capable to convert discrete data intoa function that
    can represent the rainfall curve and as a result, try to describe the hidden patterns of the
    rainfall. This study focused on the distribution of daily rainfall amount using functional
    data analysis. Fourier basis functions are used for periodic rainfall data. Generalized
    cross-validation showed 123 basis functions were sufficient to describe the pattern of daily
    rainfall amount. North and west areas of the peninsula show a significant bimodal pattern
    with the curve decline between two peaks at the mid-year. Meanwhile,the east shows uni-
    modal patterns that reached a peak in the last three months. Southern areas show more
    uniform trends throughout the year. Finally, the functional spatial method is introduced
    to overcome the problem of estimating the rainfall curve in the locations with no data
    recorded. We use a leave one out cross-validation as a verification method to compare
    between the real curve and the predicted curve. We used coefficient of basis functions
    to get the predicted curve. It was foundthatthe methods ofspatial prediction can match
    up with theexistingspatialpredictionmethodsin terms of accuracy,but it isbetterasthe new
    approach provides a simpler calculation.
  15. Fulltext Effect of active cycle of breathing technique in adult asthmatic patients in Pakistan
    Sundus, S., Memoona, S., Muhammad, I. N., Rashid, H. N.
    Asian Journal of Medicine and Biomedicine, 2018;1(1):32-37.
    MyJurnal
    Asthma is one of the chronic and long-term diseases of the airways. It is characterized by reversible airflow obstruction, chest tightness, and dyspnea with decreased work of breathing. The inside airway’s walls are swollen or inflamed. The aim of this study was to determine the effectiveness of active cycle of breathing technique as an airway clearance technique in patients with asthma. The health-related quality of life and functional capacity of patients was measured using a standardized airway questionnaire (AQ20) and six-minute walk test. The study was cohort design included 38 patients (mean age 41.131±14.711) of both genders with mild to moderate asthma. Each patient received multiple sessions (3 times/week for one month) of active cycle of breathing technique. Pre and post-treatment measures were recorded for functional capacity and health-related quality of life in the form of six-minute walk test and standardized airway questionnaire. All 38 patients were stable during the study period. The health-related quality of life and functional capacity of patient significantly improved post-treatment sessions with means [205.375±93.594 for week 1, 1248.719±112.187 for week 2, 306.429±140.5554 for week 3, 337.245±134.389 for week 4], for six-minute wall test and mean difference 4.13± 2.3 SD for standardized airway questionnaire with p-value (0.00) significant upon paired t-test. It is concluded that the active cycle of breathing technique is very beneficial intervention for improving quality of life and functional capacity of patients with mild to moderate asthma. Further, investigations are required to explore efficiency of ABCT as a tool for cardio-pulmonary rehabilitation.
  16. Fulltext Creating effective awareness campaign on the importance of martial arts among youth
    Muhammad Hadriee bin Hasnan, Rusyaizila Ramli, Safinaz Mustapha
    Journal of Management & Science, 2019;17(1):19-34.
    MyJurnal
    Bullying tends to happen most often in and around the school, specifically in the areas where adult supervision is little or none at all. Campaigns on bully awareness is proven unsuccessful considering the situation has been going on and keep happening. This also due to the lack of firm and indecisive action against the bully. This research will focus on encouraging the victims to participate and learn how to defend themselves against bully. By learning martial arts, the victim will be able to defend themselves independently and stop putting hopes for others to do so in their rights. The objective of this marketing campaign is to encourage the bully victims to learn martial arts in order to defend themselves. The promotional marketing items that will be distributed along with the campaign shall explain the benefits of learning martial arts and where they can sign up for the courses. The concept and design theme for the promotional items will be made suitable and appealing for the target audiences. An attractive publishing is proved effective as a promotional items since it has the ability to persuade and pique the interest of the victims in learning how to defend themselves against bully. This, in hope will slowly but surely reduce the frequency of bully.
  17. Highly-sensitive graphene-based flexible pressure sensor platform
    Muhammad Aniq Shazni, Lee MW, Lee HW
    Sains Malaysiana, 2017;46:1155-1161.
    In this work, graphene has been utilized as the sensing material for the development of a highly-sensitive flexible pressure sensor platform. It has been demonstrated that a graphene-based pressure sensor platform that is able to measure pressure change of up to 3 psi with a sensitivity of 0.042 psi-1 and a non-linearity of less than 1% has been accomplished. The developed device, which resides on a flexible platform, will be applicable for integration in continuous wearables health-care monitoring system for the measurement of blood pressure.
  18. Fulltext The effects of virgin coconut oil on postmenopausal osteoporotic bone: analyses on osteoblastogenesis and antioxidant genes. [Tindakan minyak kelapa dara terhadap tulang osteoporosis pascamenopaus: analisis gen osteoblastogenesis dan antioksidan]
    Shidqiyyah Abdul-Hamid, Norliza Muhammad, Isa Naina Mohamed
    Sains Malaysiana, 2016;45(12):1815-1822.
    Postmenopausal osteoporosis is one of the main health problems in aging women. It was due to several factors including oxidative stress, which can be controlled through intake of antioxidants from food sources. Virgin coconut oil (VCO) is one of the natural product rich in antioxidants and has been proven to protect osteoporotic bone. This study was conducted to gain in-depth understanding on virgin coconut oil’s activity on osteoporosis at molecular level. Thirty two female Sprague-Dawley rats were divided into four groups, namely Sham operated group, ovariectomized control group (Ovx+Ctrl), ovariectomized with VCO treatment (Ovx+VCO), and ovariectomized with estrogen treatment (Ovx+E). All treatments were administered orally for ten weeks. Bone samples were obtained to examine changes on expression of superoxide dismutase (SOD), glutathione peroxidase (GPX), osteocalcin and runt-related transcription factor 2 (Runx2) genes. The results indicated that rats receiving VCO treatment had experienced significant increments in SOD, GPX and osteocalcin gene expressions compared to the ovariectomized control group, besides the gene expressions of Runx2 which also showed an increment pattern. In conclusion, VCO helps to protect bone in osteoporotic rat model by increasing the expressions of antioxidant genes and genes which increase the osteoblast acitivities.
    Keywords: Osteoporosis; ovariectomized rat model; postmenopausal; virgin coconut oil
  19. Penemuan zon himpunan pseudoalbaillella globosa (radiolaria) di pos blau, baratdaya Kelantan, semenanjung Malaysia dan implikasinya terhadap biostratigrafi radiolaria
    Mohd Shafeea Leman, Khor Wei Chung, Muhammad Ashahadi Dzulkafli
    Sains Malaysiana, 2017;46:2349-2357.
    Fosil radiolaria yang terawet dengan agak baik telah ditemui di dalam lapisan rijang yang tersingkap di km 38, lebuhraya Gua Musang-Cameron Highland, berdekatan dengan Pos Blau, baratdaya Kelantan, Semenanjung Malaysia. Sebanyak 20 spesies fosil radiolaria telah dikenal pasti. Spesies ini mewakili zon himpunanPseudoalbaillella globosa yang menunjukkan usia (Roadian) Awal Perm Tengah. Zon himpunan radiolaria ini merupakan rekod biostratigrafi yang baru untuk jujukan batuan bersilika di Pos Blau dan di dalam Zon Sutura Bentong-Raub.
  20. Sintesis dan pencirian getah asli cecair terhidrogen untuk adunan polimer
    Muhammad Jefri Mohd Yusof, Ibrahim Abdullah, Siti Fairus M Yusoff
    Sains Malaysiana, 2017;46:1817-1823.
    Sistem hidrazin hidrat/hidrogen peroksida (HH/H2
    O2
    ) digunakan untuk menjana sumber hidrogen bagi tujuan
    penghidrogenan getah asli cecair (LNR) melalui penghasilan diimida. Spesies diimida yang terhasil akan membekalkan
    sumber hidrogen kepada ikatan karbon ganda dua dalam rantai polimer LNR. Getah asli cecair terhidrogen (HLNR)
    yang terhasil menunjukkan ciri lebih tahan suhu berbanding LNR. Suhu degradasi HLNR didapati meningkat pada 435°C
    berbanding LNR iaitu pada 381°C. HLNR seterusnya dijadikan pengserasi dalam penghasilan adunan polimer polistirena/
    getah asli, PS/NR/HLNR (60/35/5). Kekuatan regangan dan impak PS/NR masing-masing meningkat sebanyak 70.7% dan
    149.6% setelah HLNR ditambah sebagai pengserasi dalam adunan. Beberapa pemerhatian morfologi melalui mikroskop
    optik dan SEM turut menyokong kesan penyerasian adunan PS/NR dengan HLNR.
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