Displaying publications 1 - 20 of 33 in total

Abstract:
Sort:
  1. Fulltext Surface profile analysis of laminated transfemoral prosthetic socket fabricated with different ratios of epoxy resin and acrylic resin
    Zainuddin NAMN, Razak NAA, Karim MSA, Osman NAA
    Sci Rep, 2023 Feb 15;13(1):2664.
    PMID: 36792914 DOI: 10.1038/s41598-022-21990-y
    Acrylic and epoxy are common types of resin used in fabricating sockets. Different types of resin will affect the internal surface of a laminated socket. This paper is to determine the best combination of ratio for epoxy and acrylic resin for a laminated prosthesis socket and to evaluate the surface profile analysis of different combinations of laminated prosthetic sockets for surface roughness. Transfemoral sockets were created using various resin-to-hardener ratios of 2:1, 3:1, 3:2, 2:3, and 1:3 for epoxy resin and 100:1, 100:2, 100:3, 100:4, and 100:5 for acrylic resin. Eight layers of stockinette consisting of four elastic stockinette and four Perlon stockinette were used. A sample with a size of 4 cm × 6 cm was cut out from the socket on the lateral side below the Greater Trochanter area. The Mitutoyo Sj-210 Surface Tester stylus was run through the sample and gave the Average Surface Roughness value (Ra), Root Mean Square Roughness value (Rq), and Ten-Point Mean Roughness value (Rz). Epoxy resin shows a smoother surface compared to acrylic resin with Ra values of is 0.766 µm, 0.9716 µm, 0.9847 µm and 1.5461 µm with 3:2, 3:1, 2:1 and 2:3 ratio respectively. However, for epoxy resin with ratio 1:3, the resin does not cure with the hardener. As for acrylic resin the Ra values are 1.0086 µm, 2.362 µm, 3.372 µm, 4.762 µm and 6.074 µm with 100: 1, 100:2, 100:5, 100:4 and 100:3 ratios, respectively. Epoxy resin is a better choice in fabricating a laminated socket considering the surface produced is smoother.
    Matched MeSH terms: Resins, Plant
  2. Adsorption and desorption characteristics of flavonoids from white tea using macroporous adsorption resin
    Yang Y, Liang Q, Zhang B, Zhang J, Fan L, Kang J, et al.
    J Chromatogr A, 2024 Jan 25;1715:464621.
    PMID: 38198876 DOI: 10.1016/j.chroma.2023.464621
    White tea contains the highest flavonoids compared to other teas. While there have been numerous studies on the components of different tea varieties, research explicitly focusing on the flavonoid content of white tea remains scarce, making the need for a good flavonoid purification process for white tea even more important. This study compared the adsorption and desorption performance of five types of macroporous resins: D101, HP20, HPD500, DM301, and AB-8. Among the tested resins, AB-8 was selected based on its best adsorption and desorption performance to investigate the static adsorption kinetics and dynamic adsorption-desorption purification of white tea flavonoids. The optimal purification process was determined: adsorption temperature 25 °C, crude tea flavonoid extract pH 3, ethanol concentration 80 %, sample loading flow rate and eluent flow rate 1.5 BV/min, and eluent dosage 40 BV. The results indicated that the adsorption process followed pseudo-second-order kinetics. Under the above purification conditions, the purity of the total flavonoids in the purified white tea flavonoid increased from approximately 17.69 to 46.23 %, achieving a 2.61-fold improvement, indicating good purification results. The purified white tea flavonoid can be further used for nutraceutical and pharmaceutical applications.
    Matched MeSH terms: Resins, Plant
  3. Antinociceptive and antiinflammatory activities of the aqueous extract of Trigonopleura malayana resin in experimental animal models
    Sulaiman MR, Zakaria ZA, Kamaruddin A, Meng TF, Ali DI, Moin S
    Methods Find Exp Clin Pharmacol, 2008 Nov;30(9):691-6.
    PMID: 19229377 DOI: 10.1358/mf.2008.30.9.1305824
    Trigonopleura malayana L. (Euphorbiaceae) resin, locally known as Gambir Sarawak, has been used traditionally to alleviate pain associated with insect bites, muscle ache, toothache and minor injuries. The present study was carried out using various animal models to determine the antinociceptive and antiinflammatory activities of the T. malayana resin aqueous extract. Antinociceptive activity was measured using the abdominal constriction, hot plate and formalin tests, while antiinflammatory activity was measured using the carrageenan-induced paw edema test. The extract, obtained after 24 h of soaking the dried resin in distilled water, was prepared in doses of 0.3, 3 and 10 mg/kg and administered subcutaneously 30 min prior to the assays. The mechanism of action was also determined by prechallenging with naloxone (10 mg/kg), a nonselective opioid antagonist. The extract was found to exhibit significant (P < 0.05) and dose-dependent antinociceptive and antiinflammatory activities; naloxone failed to inhibit the former activity. In conclusion, the aqueous extract of T. malayana resin possesses nonopioid antinociceptive and antiinflammatory activities, thus supporting previous claims regarding its traditional use by the Malays to treat various ailments, particularly those related to pain.
    Matched MeSH terms: Resins, Plant/chemistry
  4. As-spun bio-novolac fibre morphological study based on resin’s physico-chemical properties
    Siti Noorul Aina Ab Rahim, Sarani Zakaria, Sharifah Nabihah Syed Jaafar, Chin HC, Rasidi Roslan, Hatika Kaco, et al.
    Sains Malaysiana, 2017;46:1659-1665.
    Bio-novolac fibre made from phenol-formaldehyde derived oil palm empty fruit bunch (EFB) was produced using electrospinning method. The bio-novolac phenol-formaldehyde was prepared via liquefaction and resinification at two different molar ratios of formaldehyde to liquefied EFB (LEFB) (F:LEFB = 0.5:1 and 0.8:1). Electrospinning was applied to the bio-novolac phenol-formaldehyde (BPF) in order to form smooth and thin as-spun fibre. The BPF was electrospun at 15 kV and 15 cm distance between needle and collector at a flow rate of 0.5 mL/h. At lower molecular weight of BPF resin, beads formation was observed. The addition of poly(vinyl) butyral (Mw = 175,000 - 250,000) has improved the fibre formation with lesser beads hence produced more fibre. Polymer solution with higher molecular weight produced better quality fibre.
    Matched MeSH terms: Resins, Plant
  5. Blends of LNR with unsaturated polyester resin from recycled PET: comparison of mechanical properties and morphological analysis with the optimum blend by commercial resin
    Siti Farhana Hisham, Ishak Ahmad, Rusli Daik, Anita Ramli
    Sains Malaysiana, 2011;40:1179-1186.
    In this study, poly(ethylene terephthalate) (PET) wastes bottle was recycled by glycolysis process using ethylene glycol. The unsaturated polyester resin (UPR) was then prepared by reacting the glycolysed product with maleic anhydride. The blend of UPR based on recycled PET wastes with liquid natural rubber (LNR) was carried out by varying the amount of LNR from 0 to 7.5 wt%. Mechanical tests such as tensile and impact were conducted to investigate the effects of LNR on the mechanical properties. Scanning Electron Microscopy (SEM) was used to analyze the morphology of the breaking area resulted from the tensile tests on the UPR and blend samples. From the results, the blend of 2.5 wt% LNR in UPR based recycled PET wastes achieved the highest strength in the mechanical properties and showed a well dispersed of elastomer particles in the sample morphology compared to other blends concentrations. This blend sample was then compared to the optimum blend of LNR with commercial resin through the glass transition temperature value Tg, mechanical strength and morphology properties. The comparison study showed that the Tg for UPR based recycled PET was higher than the value represented from commercial resin due to the degree of crystalinity in the molecular structure of the materials. LNR was found to be an effective impact modifier which gave a greater improvement in UPR from recycled PET wastes structure but not to the commercial one which needs 5% LNR to achieve the optimum properties. Thus, the compatibility between the UP resin based recycled PET and LNR was much better than with the commercial resin.
    Matched MeSH terms: Resins, Plant
  6. Fulltext Bond strengths of composite resins used for the attachment of bonded retainers
    Sinniah, Saraswathy D., Jones, Steven P., Georgiou, George, Cunningham, Susan J., Petrie, Aviva
    Compendium of Oral Science, 2016;3(1):17-24.
    MyJurnal
    used with bonded retainers. Setting: Department of Orthodontics, UCL Eastman Dental Institute, United Kingdom. Methods: Flowable composite resins (Transbond TM Supreme LV, StarFlowTM and Tetric EvoFlow®) and non -flowable control resin (TransbondTM LR) were made into cylinders prior to bonding to hydoxyapatite discs. They were then mounted into jigs and tested in the InstronTM Universal Testing Machine in both shear and tensile modes. Results: The highest mean shear bond strength was seen with StarFlow TM (14.09 MPa), which was significantly higher than both TransbondTM LR (9.48 MPa) and TransbondTM Supreme LV (8.20 MPa). The mean shear bond strength of Tetric EvoFlow® (11.86 MPa) was also significantly higher than TransbondTM Supreme LV. The highest mean tensile bond strength was seen with Tetric EvoFlow® (2.14 MPa), which was significantly higher than TransbondTM LR (1.15 MPa) and TransbondTM Supreme LV (0.61 MPa) but not significantly different to StarFlowTM (1.47 MPa). For shear loading, StarFlowTM had the highest 50th percentile survival estimate at 15.10 MPa, followed by Tetric EvoFlow® (13.00 MPa) and TransbondTM Supreme LV (7.50 MPa). TransbondTM LR had a 50th percentile estimate at 9.00 MPa. For tensile loading, Tetric EvoFlow® had the highest 50th percentile survival estimate at 2.50 MPa, followed by StarFlowTM (1.30 MPa) and TransbondTM Supreme LV (0.50 MPa). TransbondTM LR had a 50th percentile estimate at 1.00 MPa. Conclusions: Mean shear bond strengths for all of the resins were significantly higher than the mean tensile bond strengths. StarFlowTM and Tetric EvoFlow® could potentially be suitable clinical alternatives to TransbondTM LR due to its low viscosity flow characteristics and adequate shear and tensile bond strengths.
    Matched MeSH terms: Resins, Plant
  7. Kesan mangkin ke atas resin fenolik biopolimer dengan menggunakan kaedah pencecairan lignin soda
    Sharifah Nabihah Syed Jaafar, Sarani Zakaria, Rozaidi Rasid, Nurul Ain Zulkifli, Ali Ahmadzadeh
    Sains Malaysiana, 2010;39.
    Proses pencecairan lignin soda telah dilakukan dengan menggunakan fenol dengan nisbah 1:3. Proses dilakukan selama 90 minit pada suhu 130oC dalam keadaan refluk. Hasil pencecairan iaitu pemfenolan lignin (PL) telah dianalisis dengan Spektrometer Inframerah Transformasi Fourier (FTIR), reometer dan analisis termogravimetri (TGA). Sampel yang disintesis dengan menggunakan asid hidroklorik sebagai mangkin memberikan keputusan yang terbaik. Analisis FTIR menunjukkan kehadiran kumpulan berfungsi yang signifikan seperti gelang aromatik, alkohol dan karbonil. Kesemua sampel PL mematuhi persamaan Arhenius dan bersifat pseudo-plastik. Peratus kehilangan berat sampel dan kadar penguraian sampel PL dipengaruhi oleh jenis mangkin yang digunakan. Sampel PL yang disintesis dikelaskan sebagai biopolimer resin fenolik.
    Matched MeSH terms: Resins, Plant
  8. Penyediaan dan pencirian nanokomposit epoksi berpenguat getah ash terepoksida
    Se YEN, Sahrim Armad, Rozaidi Rasid, Yew CH, Lee YS, Tarawneh MA
    Sains Malaysiana, 2014;43:1231-1237.
    Komposit epoksi berpengisi hibrid OMMT (organ-monmorilonit) dan getah asli terepoksida (ENR) telah dihasilkan dengan menggunakan kaedah penyemperitan berskru kembar pusingan searah. Ujian regangan ke atas sistem epoksi yang dihasilkan menunjukkan modulus Young bagi komposit hibrid epoksi adalah lebih tinggi daripada resin tanpa pengisi dan nilai modulus didapati meningkat dengan peningkatan komposisi OMMT dalam matriks (setinggi 40% peningkatan). Hal ini dipercayai adalah disebabkan oleh sifat tegar lapisan MMT. Sementara itu, peningkatan luas permukaan kawasan antara fasa ekoran kehadiran fasa penambah didapati telah mengurangkan tegasan alah dan terikan akhir komposit hibrid yang dihasilkan. Pemeriksaan mikrostruktur komposit hibrid epoksi melalui TEM dan xRD mendedahkan taburan OMMT dalam matriks epoksi dengan susunan interkalasi dan pengelupasan. Analisis DSC ke atas sampel yang termatang menunjukkan bahawa T g sistem komposit hibrid adalah rendah berbanding dengan sistem perduaan (ESB dan ESLE). Pengurangan ketumpatan taut silang disyaki merupakan punca penyusutan T g ini.
    Matched MeSH terms: Resins, Plant
  9. Fulltext Feasibility study on vitrification of spent ion exchange resins from TRIGA reactor Malaysia
    Rohyiza Ba’an, Zalina Laili, Mohd Abdul Wahab Yusof, Muhamat Omar
    Journal of Nuclear and Related Technologies, 2013;2013(2):30-42.
    MyJurnal
    Feasibility studies on the vitrification of spent ion exchange resins combined with glass cullet powder have been conducted using a High Temperature Test Furnace. Bottle glass cullet powder was used as matrix material to convert the ash of the spent resins into a glass. Vitrificat ion of spent ion exchange resins presents a reasonable disposal alternative, because of its inherent organic destruction capabilities, the volume reduction levels obtainable, and the durable product that it yields. In this study, the spent ion exchange resin from the PUSPATI TRIGA reactor of Nuclear Malaysia was combusted in a lab scale combustor and the resulting ash was vitrified together with glass cullet powder in a high temperature furnace to produce a stable spent resin ash embedded in glass. The factors affecting this immobilized waste, such as thermal stability, radiological stability and leachability have all been investigated. However, the outcome of these tests, which include the radionuclide activity concentration in the slag, the optimum conditioning temperature - in relation with volume reduction during vitrification - and the volume mixing ratio of matrix material were reported. It was found that the radionuclides present in spent resins were 54 Mn, 60 Co and 152Eu. The elementary chemical composition (carbon, hydrogen, nitrogen and sulphur) of spent resins was 27.6% C, 5.68% H, 2.04% N and 4.20% S, respectively. The maximum calorific value of spent resins was 1735 kJ/kg. The average activity concentrations of 54 Mn and 60Co in ash at 200oC were 9,411 ± 243 Bq/Kg and 12,637± 201 Bq/Kg. flue gases containing CO2, CO, SO2 and NO started to be emitted above 200oC. The optimum conditioning temperature was also the highest tested, i.e. 900oC in 45 minutes, and the best mixing ratio ash to matrix material was also the highest, ie 1:9. Finally, the leaching analysis of slag at 900oC in 45 minutes showed that the leaching activity of 60Co was below 0.5 Bq/mL.
    Matched MeSH terms: Resins, Plant
  10. Linear low density polyethylene/poly (vinyl alcohol)/kenaf composites: effect of natural weathering on functional group, weight loss characteristics, tensile, morphological and thermal properties
    Pang AL, Azhar Abu Bakar, Hanafi Ismail
    Sains Malaysiana, 2018;47:571-580.
    The development of natural fiber polymer composites is increasing worldwide and in some applications, these composites
    are used at outdoor rendering them exposed to ultra-violet (UV) radiation. The paper investigates the degradation behavior
    of linear low density polyethylene/poly (vinyl alcohol)/kenaf (LLDPE/PVOH/KNF) composites after exposure to different
    natural weathering durations. The composites with KNF loadings of 10, 20 and 40 parts per hundred resin (phr) were
    exposed to natural weathering for 3 months and 6 months, respectively. The weathered composites were characterized by
    Fourier transform infrared (FTIR) spectroscopy, universal testing machine, field emission scanning electron microscopy
    (FESEM) and differential scanning calorimetry (DSC). The FTIR analysis showed an obvious carbonyl peak in composites
    after weathering as an evidence of oxidation. The weight loss percentage of composites increased with respect to exposure
    duration due to higher absorption of UV irradiation. The tensile properties of weathered composites were lower than
    that of control composites and these properties also decreased with increasing exposure duration. FESEM micrographs
    illustrated that composites with longer exposure duration suffered more surface damaged. The crystallinity percentage
    was found to increase with increasing exposure duration.
    Matched MeSH terms: Resins, Plant
  11. Fulltext Growth Enhancement of Probiotic Pediococcus acidilactici by Extractive Fermentation of Lactic Acid Exploiting Anion-Exchange Resin
    Othman M, Ariff AB, Kapri MR, Rios-Solis L, Halim M
    Front Microbiol, 2018;9:2554.
    PMID: 30420842 DOI: 10.3389/fmicb.2018.02554
    Fermentation employing lactic acid bacteria (LAB) often suffers end-product inhibition which reduces the cell growth rate and the production of metabolite. The utility of adsorbent resins for in situ lactic acid removal to enhance the cultivation performance of probiotic, Pediococcus acidilactici was studied. Weak base anion-exchange resin, Amberlite IRA 67 gave the highest maximum uptake capacity of lactic acid based on Langmuir adsorption isotherm (0.996 g lactic acid/g wet resin) compared to the other tested anion-exchange resins (Amberlite IRA 410, Amberlite IRA 400, Duolite A7 and Bowex MSA). The application of Amberlite IRA 67 improved the growth of P. acidilactici about 67 times compared to the control fermentation without resin addition. Nevertheless, the in situ addition of dispersed resin in the culture created shear stress by resins collision and caused direct shear force to the cells. The growth of P. acidilactici in the integrated bioreactor-internal column system containing anion-exchange resin was further improved by 1.4 times over that obtained in the bioreactor containing dispersed resin. The improvement of the P. acidilactici growth indicated that extractive fermentation using solid phase is an effective approach for reducing by-product inhibition and increasing product titer.
    Matched MeSH terms: Resins, Plant
  12. Effect of aluminum hydroxide loading on the compression stress and modulus, thermal conductivity and acoustic properties of palm-based polyurethane hybrid composite
    Nor Rabbi’atul ‘Adawiyah Norzali, Khairiah Badri, Mohd Zaki Nuawi
    Sains Malaysiana, 2011;40.
    The effect of adding aluminum hydroxide (ATH) in the palm-based polyurethane hybrid composite was studied. The compression stress and modulus, thermal conductivity and acoustic property were determined. The hybrid composite was prepared by adding 10 wt% of oil palm empty fruit bunch fibre (EFB) followed by ATH at varying amount of 2, 4 and 6 wt% of the overall mass of the resin. The compression stress and modulus gave the highest values of 575 kPa and 2301 kPa, respectively at 2 wt% ATH. At 4 wt% ATH, the compression stress and modulus decreased to 431 kPa and 1659 kPa, respectively and further decreased at 6 wt% ATH to 339 kPa and 1468 kPa respectively. The k-value increased with the increment of the ATH loading exhibited a poor thermal conductivity. Sound absorption analysis indicated that the absorption coefficient was higher at higher frequency (4000 Hz) for all samples with PU-EFB/ATH with 4% ATH showed the highest absorption coefficient.
    Matched MeSH terms: Resins, Plant
  13. Loading effect of aluminum hydroxide onto them mechanical, thermal conductivity, acoustical and burning properties of the palm-based polyurethane composites
    Nor Rabbi’atul ‘Adawiyah Norzali, Khairiah Badri, Mohd Zaki Nuawi
    Sains Malaysiana, 2011;40:1179-1186.
    Effects of aluminium hydroxide (ATH) addition on the properties of palm-based polyurethane composites were investigated. The hybrid composites were prepared by mixing 10 wt% of oil palm empty fruit bunch fiber (EFB) with ATH at varying amount of 2, 4 and 6 wt% of the overall mass of the resin. The compression stress and modulus gave the highest values of 575 and 2301 kPa, respectively at 2 wt% loading of ATH. The compression stress and modulus decreased drastically at 4 wt% (431 kPa and 1659 kPa, respectively) and further decreased at 6 wt% ATH (339 and 1468 kPa, respectively). However, the burning rate is inversely proportional to the loading percentage where the highest burning rate was observed at 2 wt% ATH. Sound absorption analysis indicated a large absorption coefficient at high frequency (4000 Hz) for all samples. The highest absorption coefficient was obtained from PU-EFB/ATH with 4 wt% ATH.
    Matched MeSH terms: Resins, Plant
  14. Fulltext Effects of Starter Defect on Energy Release Rate of Three-Point End-Notch Flexure Tested Unidirectional Carbon Fiber Reinforced Polymer Composite
    Nor FM, Lim JY, Tamin MN, Lee HY, Kurniawan D
    Polymers (Basel), 2020 Apr 14;12(4).
    PMID: 32295111 DOI: 10.3390/polym12040904
    The mechanics of damage and fracture process in unidirectional carbon fiber reinforced polymer (CFRP) composites subjected to shear loading (Mode II) were examined using the experimental method of the three-point end-notch flexure (3ENF) test. The CFRP composite consists of [0o]16 with an insert film in the middle plane for a starter defect. A 3ENF test sample with a span of 50 mm and interface delamination crack length of 12.5 mm was tested to yield the load vs. deformation response. A sudden load drop observed at maximum force value indicates the onset of delamination crack propagation. The results are used to extract the energy release rate, GIIC, of the laminates with an insert film starter defect. The effect of the starter defect on the magnitude of GIIC was examined using the CFRP composite sample with a Mode II delamination pre-crack. The higher magnitude of GIIC for the sample with insert film starter defect was attributed to the initial straight geometry of the notch/interface crack and the toughness of the resin at the notch front of the fabricated film insert. The fractured sample was examined using a micro-computerized tomography scanner to establish the shape of the internal delamination crack front. Results revealed that the interface delamination propagated in a non-uniform manner, leaving a curved-shaped crack profile.
    Matched MeSH terms: Resins, Plant
  15. Fulltext In vitro study of white spot lesion: Maxilla and mandibular teeth
    Mohamed AM, Wong KH, Lee WJ, Marizan Nor M, Mohd Hussaini H, Rosli TI
    Saudi Dent J, 2018 Apr;30(2):142-150.
    PMID: 29628737 DOI: 10.1016/j.sdentj.2017.12.001
    Aim: The aim of the study was to evaluate the effect of resin infiltration on colour changes and surface roughness of artificial white spot lesions (WSLs) on maxillary and mandibular premolar.

    Materials and methods: Sixty (60) extracted sound Maxilla (Mx) and Mandibular (Mn) premolars were randomly divided into 2 groups (test and control). Artificial WSLs were produced on buccal surface of teeth and were immersed in artificial saliva for 8 weeks. Colour components (L∗, a∗, b∗) and surface roughness (Sa∗) were assessed on 40 teeth using colour difference meter RD-100 and Alicona® Infinite Focus profilometer respectively. The measurements were done at baseline (T1), directly after artificial WSLs (T2), after 24 hours immersed in saliva and application of resin (T3) and immersion in artificial saliva for 1 (T4), 2 (T5), 4 (T6), 6 (T7) and 8 (T8) weeks. SEM images analysis were carried out on 20 teeth in four time points.

    Results: The values of L∗ (lightness), b∗ (yellow/blue) and Sa∗ (surface roughness) are gradually reduced to the baseline value. Whereas, the value of a∗ gradually increased with distinct treatment time to achieve the baseline value. The higher value of L∗ and Sa∗, the whiter the lesion suggesting higher degree of enamel demineralization and surface roughness. Lower L∗ values suggest a masking colour effect.

    Conclusion: The material produced favorable esthetics on colour and the surface roughness of teeth at distinct treatment times. It is recommended to be used to improve WSL post orthodontic treatment.

    Matched MeSH terms: Resins, Plant
  16. Solid-state self-healing systems: the diffusion of healing agent for healing recovery
    Md Jamil M, Jones F, Muhamad N, Makenan S
    Sains Malaysiana, 2015;44:843-852.
    A clear understanding on the fundamental mechanism in solid state self-healing resin system might significantly improve the optimization of healing performance. The focus of this study was to prove the diffusion (through thermal inter-diffusion) of a linear healing agent within the network matrix resin. The results had demonstrated that 45 to 21 percentage recoveries in fracture toughness (K1C) were observed within the third healing cycles of the healable resin. Based on the optical microscopy, scanning electron microscopy (SEM) and time-of-flight secondary ion mass spectrometry (ToF-SIM) analyst; the diffusion of healing agent was also demonstrated by the change in the morphology and chemical images of the healing agent on the fracture surface specimen, before and after healing process.
    Matched MeSH terms: Resins, Plant
  17. Perubahan nisbah 234U/238U dalam pepejal terampai di Kuala Selangor, Selangor, Malaysia
    Khairul Nizam Mohd Ramli, Che Abd. Rahim Mohamed, Zaharuddin Ahmad
    Sains Malaysiana, 2007;36:9-13.
    Kajian ini dijalankan bagi mengenalpasti kepelbagaian nisbah 234U/238U yang wujud di dalam jumlah pepejal terampai (TSS) pada lapan stesen yang berbeza di Kuala Selangor, Selangor. Prosedur kajian ini melibatkan proses persampelan, pemendakan, resin penukaran anion, pemendakan elektrik dan teknik pengiraaan spektrometer alfa. Nisbah 234U/238U adalah paling tinggi di Stesen 8 (234U/238U = 2.98) dan Stesen 2 (234U/238U = 3.34) pada persampelan pertama. Manakala pada persampelan kedua julat nisbah 234U/238U adalah lebih luas iaitu antara 1.29 (Stesen 4) hingga 11.57 (Stesen 6). Ini disebabkan oleh berlakunya pergerakan 234U bersama-sama mikroorganisme di dalam fasa terampai dan berlaku proses penurunan U(VI) kepada U(IV) yang akan memendakkan uranium daripada air ke dalam sedimen.
    Matched MeSH terms: Resins, Plant
  18. Fulltext High resolution images of resin structure in agarwood by means of sem and micro-CT
    Khairiah Yazid @ Khalid, Roslan Yahya, Nadira Kamarudini, Mohd. Zaid Abdullah, Mohd Ashhar Khalid, Abdul Aziz Mohamed
    Jurnal Sains Nuklear Malaysia, 2012;24(2):42-49.
    MyJurnal
    Detection and analysis of resin is particularly significant since the commercial value of agarwood is related to the quantity of resins that are present. This article explores the potential of a scanning electron microscope in combination with new non-destructive 3D visualization technique, X-ray micro-computed tomography, as imaging tools to visualize micro-structure resin in agarwood. These techniques were used to compare two samples of agarwood chips: high grade and low grade. From the results, it can be concluded that a wood cell filled with resin deposit have a higher attenuation. It can be shown that the combination of scanning electron microscopy and micro-CT can offer high resolution images concerning the localization and structure of resin inside Agarwood. While the second allows the 3D investigation of internal structure of agarwood, the first technique can provide details 2D morphological information. These imaging techniques, although sophisticated can be used for standard development especially in grading of agarwoodlbr commercial activities.
    Matched MeSH terms: Resins, Plant
  19. Effect of phosphite loading on the mechanical and fire properties of palm-based polyurethane
    Khairiah Badri, Amamer Musbah Redwan
    Sains Malaysiana, 2010;39.
    Fire-retarding polyurethane (PU) composite was produced by adding 2,4-ditert-butylphenyl phosphite (FR) to palm-based monoester resin with loading percentage of 0, 2, 4, and 6 wt%. The Shore D hardness index increased marginally with increasing FR content. However, the impact and flexural strengths decreased with increasing FR loading attributed to the weak interfacial bonding between FR and PU matrix. The fire test indicated lowering of burning rate (from 5.30 mm.s-1 to 2.80 mm.s-1) as the loading percentage of FR increased. The combustion enthalpy of the composites also decreased with higher loading percentage of FR.
    Matched MeSH terms: Resins, Plant
  20. Fulltext Colour vision of workers in the plastics industry
    Kaur S, Mursyid A, Ariffin AE
    Journal of Occupational Safety and Health, 2004;1(1):25-30.
    MyJurnal
    A study was undertaken to determine the effect of polyethylene and polystyrene used in the manufacture of plastic items on colour perception. Colour vision was assessed using the Ishihara plates, panel 015 test and the Farnsworth Munsell 100-Hue test. Two factories were chosen at random. One factory (referred here as factory A) used virgin resin in pellet form (polyethylene) in the manufacturing of plastic containers to store consumer edible oil. The other factory (referred as factory B) used polystyrene to make plastic bags. A total of 39 healthy employees from factory A (mean age 26.4 :t 8.2 years) and 40 healthy employees from factory B (mean age 26.8 :t 9.6 years) were recruited in this study. A control group of 27 normal healthy subjects (mean age 27.4 :t 4.3 years) who were employees of UKM with no occupational involvement with petroleum derivatives were also recruited in this study and they performed the same colour vision tests. All subjects passed the Ishihara plates test showing that none of the subjects (employees of factory A and B, and control subjects) had a congenital red-green defect. All control subjects passed all of the colour vision tests whilst some employees of factories A and B failed the 015 and FM100 Hue tests. For employees from factory A results from the 015 test showed that 7 (17.9%) had a tritan (blue-yellow) type of defect and 1 (2.6%) had a complex type of defect. The FM 100 Hue results of factory A employees showed that 51.3% (n=20) had a complex type of defect. Total error scores (TES) calculated from the FM 100 Hue test revealed that employees from factory A had a statistically significant higher mean TES of 65.13:!: 48.31 compared to that of control subjects with a mean TES of 31.26:!: 14.93. For employees in factory B, 10 employees (25.0%) had a tritan (blue-yellow) type of defect and 2 (5.0%) had a complex type of defect. Results of the FM 100 Hue test showed that 4 employees (1.0%) had a tritan type of defect whereas 22 (55.0%) had a complex type of defect. Mean total error scores (TES) calculated from the FM 100 Hue test revealed that employees from factory B had a statistically significant higher mean TES of 71.54 :t 54.63 compared with that of control subjects with a mean TES of 31.26 :t. 14.93

    The above results show that employees of the plastic factories studies are associated with a higher risk of acquiring colour vision defects as compared to normal subjects who are not engaged in the plastic manufacturing industry. This may have an implication towards the future retinal health of employees in petrod1emical-based industries.
    Matched MeSH terms: Resins, Plant
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links