Displaying publications 1 - 20 of 137 in total

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  1. Leong SS, Wong JHD, Md Shah MN, Vijayananthan A, Jalalonmuhali M, Ng KH
    Ultrasound Med Biol, 2019 06;45(6):1417-1426.
    PMID: 30962016 DOI: 10.1016/j.ultrasmedbio.2019.01.024
    The purpose of this study was to assess the potential of shear wave elastography (SWE) as an indicator of abnormal kidney function defined by radiolabeled glomerular filtration rate (GFR). Fifty-seven patients referred for 51Cr-ethylenediaminetetraacetic acid GFR and 99mTc-dimercaptosuccinic acid renal scintigraphy were included. Young's modulus (YM) measured with SWE and kidney length, volume, cortical thickness and parenchymal echogenicity measured with conventional ultrasound were correlated with patients' GFR and renal scintigraphy results. Spearman correlation coefficients between SWE and GFR were negative for the right (r = -0.635, p < 0.0001) and left (r = -0.817, p < 0.0001) kidneys. Positive correlations between left renal cortical thickness (r = 0.381, p = 0.04) and left kidney volume (r = 0.356, p = 0.019) with GFR were reported. SWE correctly predicted the dominant functioning kidney in 94.7% of cases. The area under the receiver operating characteristic curve for SWE (0.800) was superior to that for conventional ultrasound (0.252-0.415). The cutoff value of ≥5.52 kPa suggested a kidney function ≤60 mL/min/1.73 m2 (82.4% sensitivity and 76.2% specificity). SWE has advantages over conventional ultrasound in assessing kidney function and distinguishing the dominant functioning kidney.
    Matched MeSH terms: Elastic Modulus
  2. Lim WTH, Ooi EH, Foo JJ, Ng KH, Wong JHD, Leong SS
    Ultrasonics, 2023 Aug;133:107046.
    PMID: 37247461 DOI: 10.1016/j.ultras.2023.107046
    The application of ultrasound shear wave elastography for detecting chronic kidney disease, namely renal fibrosis, has been widely studied. A good correlation between tissue Young's modulus and the degree of renal impairment has been established. However, the current limitation of this imaging modality pertains to the linear elastic assumption used in quantifying the stiffness of renal tissue in commercial shear wave elastography systems. As such, when underlying medical conditions such as acquired cystic kidney disease, which may potentially influence the viscous component of renal tissue, is present concurrently with renal fibrosis, the accuracy of the imaging modality in detecting chronic kidney disease may be affected. The findings in this study demonstrate that quantifying the stiffness of linear viscoelastic tissue using an approach similar to those implemented in commercial shear wave elastography systems led to percentage errors as high as 87%. The findings presented indicate that use of shear viscosity to detect changes in renal impairment led to a reduction in percentage error to values as low as 0.3%. For cases in which renal tissue was affected by multiple medical conditions, shear viscosity was found to be a good indicator in gauging the reliability of the Young's modulus (quantified through a shear wave dispersion analysis) in detecting chronic kidney disease. The findings show that percentage error in stiffness quantification can be reduced to as low as 0.6%. The present study demonstrates the potential use of renal shear viscosity as a biomarker to improve the detection of chronic kidney disease.
    Matched MeSH terms: Elastic Modulus
  3. GUI CHAN LEE, NORIZAH MHD. SARBON
    MyJurnal
    Plastics packaging is non-biodegradable and risks to human health and environmental pollution. In contrast, gelatin-based film lack of desired mechanical, thermal and water vapour barrier properties. Thus, this study aimed to investigate the mechanical and physical properties of bio-nanocomposite films based on chicken skin gelatin with different concentration of chitosan nanoparticles (CSNPs). Gelatin/CSNPs film solutions with different CSNPs concentration (0-8%, w/w) were stirred at 45oC for 30 min and oven-dried at 45oC. Film characterization determination includes tensile strength (TS), elongation at break (EAB), Young’s modulus (YM), water solubility, water vapour permeability (WVP), film morphology and melting temperature (Tm). Results of the study indicated that incorporation of CSNPs significantly influenced film properties. The addition of CSNPs increased the TS and YM value, which lead to stronger films than the pure chicken skin gelatin films. However the addition of CSNPs decreased the EAB value. Furthermore, WVP and water solubility significantly decreased (p < 0.05) by the addition of 6% CSNPs. Morphology images showed that increased CSNPs reduced the film’s amorphous character, especially in high level, in which higher CSNPs (8%) resulted in the aggregation of particles in the composites. The nano-reinforcement films showed higher thermal stability as compared to pure chicken skin gelatin films. In conclusion, the film with 6% CSNPs showed the best formulation, as it demonstrated high in TS, YM and Tm value, while low in EAB, water solubility and WVP value compared to other films. The results presented in this study showed the feasibility of using bio-nanocomposite technology to improve the properties of biopolymer films based on chicken skin gelatin.
    Matched MeSH terms: Elastic Modulus
  4. Ataollahi Oshkour A, Pramanik S, Shirazi SF, Mehrali M, Yau YH, Abu Osman NA
    ScientificWorldJournal, 2014;2014:616804.
    PMID: 25538954 DOI: 10.1155/2014/616804
    This study investigated the impact of calcium silicate (CS) content on composition, compressive mechanical properties, and hardness of CS cermets with Ti-55Ni and Ti-6Al-4V alloys sintered at 1200°C. The powder metallurgy route was exploited to prepare the cermets. New phases of materials of Ni16Ti6Si7, CaTiO3, and Ni31Si12 appeared in cermet of Ti-55Ni with CS and in cermet of Ti-6Al-4V with CS, the new phases Ti5Si3, Ti2O, and CaTiO3, which were emerged during sintering at different CS content (wt%). The minimum shrinkage and density were observed in both groups of cermets for the 50 and 100 wt% CS content, respectively. The cermets with 40 wt% of CS had minimum compressive Young's modulus. The minimum of compressive strength and strain percentage at maximum load were revealed in cermets with 50 and 40 wt% of CS with Ti-55Ni and Ti-6Al-4V cermets, respectively. The cermets with 80 and 90 wt% of CS showed more plasticity than the pure CS. It concluded that the composition and mechanical properties of sintered cermets of Ti-55Ni and Ti-6Al-4V with CS significantly depend on the CS content in raw cermet materials. Thus, the different mechanical properties of the cermets can be used as potential materials for different hard tissues replacements.
    Matched MeSH terms: Elastic Modulus*
  5. Oshkour AA, Talebi H, Shirazi SF, Bayat M, Yau YH, Tarlochan F, et al.
    ScientificWorldJournal, 2014;2014:807621.
    PMID: 25302331 DOI: 10.1155/2014/807621
    This study is focused on finite element analysis of a model comprising femur into which a femoral component of a total hip replacement was implanted. The considered prosthesis is fabricated from a functionally graded material (FGM) comprising a layer of a titanium alloy bonded to a layer of hydroxyapatite. The elastic modulus of the FGM was adjusted in the radial, longitudinal, and longitudinal-radial directions by altering the volume fraction gradient exponent. Four cases were studied, involving two different methods of anchoring the prosthesis to the spongy bone and two cases of applied loading. The results revealed that the FG prostheses provoked more SED to the bone. The FG prostheses carried less stress, while more stress was induced to the bone and cement. Meanwhile, less shear interface stress was stimulated to the prosthesis-bone interface in the noncemented FG prostheses. The cement-bone interface carried more stress compared to the prosthesis-cement interface. Stair climbing induced more harmful effects to the implanted femur components compared to the normal walking by causing more stress. Therefore, stress shielding, developed stresses, and interface stresses in the THR components could be adjusted through the controlling stiffness of the FG prosthesis by managing volume fraction gradient exponent.
    Matched MeSH terms: Elastic Modulus
  6. Zakaria NM, Yusoff NI, Hardwiyono S, Nayan KA, El-Shafie A
    ScientificWorldJournal, 2014;2014:594797.
    PMID: 25276854 DOI: 10.1155/2014/594797
    Enhanced resonance search (ERS) is a nondestructive testing method that has been created to evaluate the quality of a pavement by means of a special instrument called the pavement integrity scanner (PiScanner). This technique can be used to assess the thickness of the road pavement structure and the profile of shear wave velocity by using the principle of surface wave and body wave propagation. In this study, the ERS technique was used to determine the actual thickness of the asphaltic pavement surface layer, while the shear wave velocities obtained were used to determine its dynamic elastic modulus. A total of fifteen locations were identified and the results were then compared with the specifications of the Malaysian PWD, MDD UKM, and IKRAM. It was found that the value of the elastic modulus of materials is between 3929 MPa and 17726 MPa. A comparison of the average thickness of the samples with the design thickness of MDD UKM showed a difference of 20 to 60%. Thickness of the asphalt surface layer followed the specifications of Malaysian PWD and MDD UKM, while some of the values of stiffness obtained are higher than the standard.
    Matched MeSH terms: Elastic Modulus*
  7. Kam CZ, Kueh AB
    ScientificWorldJournal, 2013;2013:350890.
    PMID: 24319360 DOI: 10.1155/2013/350890
    A laminated composite plate element with an interface description is developed using the finite element approach to investigate the bending performance of two-layer cross-ply laminated composite plates in presence of a diagonally perturbed localized interfacial degeneration between laminae. The stiffness of the laminate is expressed through the assembly of the stiffnesses of lamina sub-elements and interface element, the latter of which is formulated adopting the well-defined virtually zero-thickness concept. To account for the extent of both shear and axial weak bonding, a degeneration ratio is introduced in the interface formulation. The model has the advantage of simulating a localized weak bonding at arbitrary locations, with various degeneration areas and intensities, under the influence of numerous boundary conditions since the interfacial description is expressed discretely. Numerical results show that the bending behavior of laminate is significantly affected by the aforementioned parameters, the greatest effect of which is experienced by those with a localized total interface degeneration, representing the case of local delamination.
    Matched MeSH terms: Elastic Modulus
  8. Manssor NA, Radzi Z, Yahya NA, Mohamad Yusof L, Hariri F, Khairuddin NH, et al.
    Skin Pharmacol Physiol, 2016;29(2):55-62.
    PMID: 26836267 DOI: 10.1159/000431328
    Mechanical properties of expanded skin tissue are different from normal skin, which is dependent mainly on the structural and functional integrity of dermal collagen fibrils. In the present study, mechanical properties and surface topography of both expanded and nonexpanded skin collagen fibrils were evaluated. Anisotropic controlled rate self-inflating tissue expanders were placed beneath the skin of sheep's forelimbs. The tissue expanders gradually increased in height and reached equilibrium in 2 weeks. They were left in situ for another 2 weeks before explantation. Expanded and normal skin samples were surgically harvested from the sheep (n = 5). Young's modulus and surface topography of collagen fibrils were measured using an atomic force microscope. A surface topographic scan showed organized hierarchical structural levels: collagen molecules, fibrils and fibers. No significant difference was detected for the D-banding pattern: 63.5 ± 2.6 nm (normal skin) and 63.7 ± 2.7 nm (expanded skin). Fibrils from expanded tissues consisted of loosely packed collagen fibrils and the width of the fibrils was significantly narrower compared to those from normal skin: 153.9 ± 25.3 and 106.7 ± 28.5 nm, respectively. Young's modulus of the collagen fibrils in the expanded and normal skin was not statistically significant: 46.5 ± 19.4 and 35.2 ± 27.0 MPa, respectively. In conclusion, the anisotropic controlled rate self-inflating tissue expander produced a loosely packed collagen network and the fibrils exhibited similar D-banding characteristics as the control group in a sheep model. However, the fibrils from the expanded skin were significantly narrower. The stiffness of the fibrils from the expanded skin was higher but it was not statistically different.
    Matched MeSH terms: Elastic Modulus/physiology*
  9. Rad MA, Tijjani AS, Ahmad MR, Auwal SM
    Sensors (Basel), 2016 Dec 23;17(1).
    PMID: 28025571 DOI: 10.3390/s17010014
    This paper proposes a new technique for real-time single cell stiffness measurement using lead zirconate titanate (PZT)-integrated buckling nanoneedles. The PZT and the buckling part of the nanoneedle have been modelled and validated using the ABAQUS software. The two parts are integrated together to function as a single unit. After calibration, the stiffness, Young's modulus, Poisson's ratio and sensitivity of the PZT-integrated buckling nanoneedle have been determined to be 0.7100 N·m-1, 123.4700 GPa, 0.3000 and 0.0693 V·m·N-1, respectively. Three Saccharomyces cerevisiae cells have been modelled and validated based on compression tests. The average global stiffness and Young's modulus of the cells are determined to be 10.8867 ± 0.0094 N·m-1 and 110.7033 ± 0.0081 MPa, respectively. The nanoneedle and the cell have been assembled to measure the local stiffness of the single Saccharomyces cerevisiae cells The local stiffness, Young's modulus and PZT output voltage of the three different size Saccharomyces cerevisiae have been determined at different environmental conditions. We investigated that, at low temperature the stiffness value is low to adapt to the change in the environmental condition. As a result, Saccharomyces cerevisiae becomes vulnerable to viral and bacterial attacks. Therefore, the proposed technique will serve as a quick and accurate process to diagnose diseases at early stage in a cell for effective treatment.
    Matched MeSH terms: Elastic Modulus/drug effects
  10. Higuchi A, Kao SH, Ling QD, Chen YM, Li HF, Alarfaj AA, et al.
    Sci Rep, 2015 Dec 14;5:18136.
    PMID: 26656754 DOI: 10.1038/srep18136
    The tentative clinical application of human pluripotent stem cells (hPSCs), such as human embryonic stem cells and human induced pluripotent stem cells, is restricted by the possibility of xenogenic contamination resulting from the use of mouse embryonic fibroblasts (MEFs) as a feeder layer. Therefore, we investigated hPSC cultures on biomaterials with different elasticities that were grafted with different nanosegments. We prepared dishes coated with polyvinylalcohol-co-itaconic acid hydrogels grafted with an oligopeptide derived from vitronectin (KGGPQVTRGDVFTMP) with elasticities ranging from 10.3 to 30.4 kPa storage moduli by controlling the crosslinking time. The hPSCs cultured on the stiffest substrates (30.4 kPa) tended to differentiate after five days of culture, whereas the hPSCs cultured on the optimal elastic substrates (25 kPa) maintained their pluripotency for over 20 passages under xeno-free conditions. These results indicate that cell culture matrices with optimal elasticity can maintain the pluripotency of hPSCs in culture.
    Matched MeSH terms: Elastic Modulus
  11. Mehmood A, Mubarak NM, Khalid M, Jagadish P, Walvekar R, Abdullah EC
    Sci Rep, 2020 11 18;10(1):20106.
    PMID: 33208815 DOI: 10.1038/s41598-020-77139-2
    Strain sensors in the form of buckypaper (BP) infiltrated with various polymers are considered a viable option for strain sensor applications such as structural health monitoring and human motion detection. Graphene has outstanding properties in terms of strength, heat and current conduction, optics, and many more. However, graphene in the form of BP has not been considered earlier for strain sensing applications. In this work, graphene-based BP infiltrated with polyvinyl alcohol (PVA) was synthesized by vacuum filtration technique and polymer intercalation. First, Graphene oxide (GO) was prepared via treatment with sulphuric acid and nitric acid. Whereas, to obtain high-quality BP, GO was sonicated in ethanol for 20 min with sonication intensity of 60%. FTIR studies confirmed the oxygenated groups on the surface of GO while the dispersion characteristics were validated using zeta potential analysis. The nanocomposite was synthesized by varying BP and PVA concentrations. Mechanical and electrical properties were measured using a computerized tensile testing machine, two probe method, and hall effect, respectively. The electrical conducting properties of the nanocomposites decreased with increasing PVA content; likewise, electron mobility also decreased while electrical resistance increased. The optimization study reports the highest mechanical properties such as tensile strength, Young's Modulus, and elongation at break of 200.55 MPa, 6.59 GPa, and 6.79%, respectively. Finally, electrochemical testing in a strain range of ε ~ 4% also testifies superior strain sensing properties of 60 wt% graphene BP/PVA with a demonstration of repeatability, accuracy, and preciseness for five loading and unloading cycles with a gauge factor of 1.33. Thus, results prove the usefulness of the nanocomposite for commercial and industrial applications.
    Matched MeSH terms: Elastic Modulus
  12. Karimzadeh A, R Koloor SS, Ayatollahi MR, Bushroa AR, Yahya MY
    Sci Rep, 2019 10 31;9(1):15763.
    PMID: 31673118 DOI: 10.1038/s41598-019-51904-4
    This study investigates the capacity of the nano-indentation method in the mechanical characterization of a heterogeneous dental restorative nanocomposite using experimental and computational approaches. In this respect, Filtek Z350 XT was selected as a nano-particle reinforced polymer nanocomposite with a specific range of the particle size (50 nm to 4 µm), within the range of indenter contact area of the nano-indentation experiment. A Sufficient number of nano-indentation tests were performed in various locations of the nanocomposite to extract the hardness and elastic modulus properties. A hybrid computational-experimental approach was developed to examine the extracted properties by linking the internal behaviour and the global response of the nanocomposite. In the computational part, several representative models of the nanocomposite were created in a finite element environment to simulate the mechanism of elastic-plastic deformation of the nanocomposite under Berkovich indenter. Dispersed values of hardness and elastic modulus were obtained through the experiment with 26.8 and 48.5 percent average errors, respectively, in comparison to the nanocomposite properties, respectively. A disordered shape was predicted for plastic deformation of the equilateral indentation mark, representing the interaction of the particles and matrix, which caused the experiment results reflect the local behaviour of the nanocomposite instead of the real material properties.
    Matched MeSH terms: Elastic Modulus
  13. Matsumura Y, Kamimura Y, Lee CY, Gorb SN, Rajabi H
    Sci Rep, 2021 04 12;11(1):7920.
    PMID: 33846369 DOI: 10.1038/s41598-021-86864-1
    We unveiled the penile penetration mechanics of two earwig species, Echinosoma horridum, whose intromittent organ, termed virga, is extraordinarily long, and E. denticulatum, whose virga is conversely short. We characterised configuration, geometry, material and bending stiffness for both virga and spermatheca. The short virga of E. denticulatum has a material gradient with the stiffer base, whereas the long virga of E. horridum and the spermathecae of both species are homogeneously sclerotised. The long virga of E. horridum has a lower bending stiffness than the spermatheca. The virga of E. denticulatum is overall less flexible than the spermatheca. We compared our results to a previous study on the penetration mechanics of elongated beetle genitalia. Based on the comparison, we hypothesised that the lower stiffness of the male intromittent organ comparing to the corresponding female structure is a universal prerequisite for the penetration mechanics of the elongated intromittent organ in insects.
    Matched MeSH terms: Elastic Modulus
  14. Shahril Anuar Bahari, Kamrie Kamlon, Masitah Abu Kassim
    MyJurnal
    In this study, the rice husk flour-plastic waste composites (RPC) was produced from polypropylene (PP) and high density polyethylene (HDPE) wastes with 30 and 50% rice husk flour (RHF) contents. RPC was made by melt compounding and compression moulding processes. The electrical resistivity, thermal stability and tensile strength of RPC were determined. The RPC was tested in electrical resistivity and tensile strength according to the ASTM D-257 and ASTM D-638 respectively, while thermal stability was tested using thermogravimetric analysis (TGA) method. From the results, high content of RHF reduces all properties, except for tensile modulus of elasticity (TMOE) in tensile strength test. The ability of moisture absorption and the presence of hemicelluloses, cellulose and silica in RHF reduce the electrical resistivity and thermal stability behaviour of RPC from 50% RHF. The good binding elements and filler agglomeration in RPC from 50% RHF improve only TMOE. Insufficient stress transfer and rigid interphase occurred between RHF and plastics during tensile maximum load and elongation at break (Eb) in tensile strength test. In general, RPC from HDPE indicates better thermal stability, tensile modulus of rupture and Eb (in tensile strength test) compared to PP, based on the good behaviour of thermal conductivity, low water absorption, high molecular weight and good elongation properties of HDPE. However, RPC from PP shows good electrical resistance due to the low thermal expansion coefficient of PP.
    Matched MeSH terms: Elastic Modulus
  15. Lee JC, Payam Shafigh, Hilmi Mahmud, Muhammad Aslam
    Sains Malaysiana, 2017;46:645-653.
    Oil-palm-boiler clinker (OPBC) is an agricultural solid waste sourced from the palm oil industry in tropical regions. This study investigates the use of OPBC as coarse aggregate instead of conventional coarse aggregates to produce a greener concrete, which will help in implementing sustainable construction practices by reducing the usage of raw materials. For this purpose, normal weight coarse aggregates was substituted with dry OPBC aggregates up to 75% (by volume) in a high strength normal weight concrete. The effectiveness of this substitution on the properties of the concrete such as workability, density, compressive strength, splitting tensile strength and modulus of elasticity was studied. The slump test results showed that using OPBC in dry condition reduced the workability of the concrete and therefore can be used up to 50% of the total volume of coarse aggregate. Concrete containing 50% OPBC can be considered as semi-lightweight concrete with high strength. Using OPBC in concrete reduced the splitting tensile strength and modulus of elasticity, however, the reduction was not significant.
    Matched MeSH terms: Elastic Modulus
  16. Zaidon A, Kim G, Bakar E, Rasmina H
    Sains Malaysiana, 2014;43:775-782.
    The aim of the study was to develop response surface methodology (RSM) models for polymer loading, density, dimensional stability, strength and stiffness of compressed wood of sesenduk (Endospermum diadenum) treated with phenol formaldehyde (PF). Central composite design (CCD) using RSM with three processing parameters was studied in their specific ranges: PF concentration (PC) from 24-40%, pre-curing time (PCT), 3-9 h and compression ratio (CR), 70-90%. The experimental design was analysed and interpreted using the Design Expert Software (Stat Ease version 8) and the responses of 3d plots were built using the same software. Quadratic models in terms of PC, PCT and CR were developed for polymer loading, density, reduction in water absorption and modulus of rupture in static bending. Multiple linear equations were developed for anti-swelling efficiency and modulus of elasticity. The experimental values were in good agreement with predicted ones and the models were highly significant with correlation coefficients between 0.626 and 0.926. PC and CR had significant effects on the responses. The range of PCT used did not significantly affect the responses. It was also found that the improvement of properties ranged from moderately to highly correlated with the polymer loading in the compreg wood.
    Matched MeSH terms: Elastic Modulus
  17. Umar Hamzah, Ibrahim Komoo
    A survey to characterize seismic and ultrasonic properties of a granite weathering profile have been carried out at a roadcut slope exposure along Kuala Lumpur-Karak highway at kilometres 39.9. The terraced cut slope shows a complete weathering profile beginning from fresh grade I rock to grade VI residual soil. Together with in situ seismic measurement, rock samples have been collected for ultrasonic tests in laboratory. The range of velocities representing grades and indices of weathered rocks and soils are determined from the in situ seismic surveys. The range of ultrasonic velocities and elastic moduli are obtained from the laboratory measurements.
    Satu survei untuk mencirikan sifat seismos dan ultrasonik profil luluhawa granit telah dilakukan di singkapan potongan jalan, cerun utara lebuhraya Kuala Lumpur-Karak pada lokaliti 39.9 km. Potongan berteres ini mempamirkan satu profil luluhawa lengkap iaitu mulai batuan gred 1 yang segar hingga ke tanah baki bergred VI. Di samping pengukuran seismos secara in situ, sampel batuan juga diambil untuk dibuat pengukuran halaju ultrasonik di makmal. Julat halaju yang mewakili gred dan indeks luluhawa bagi tanah dan batuan diperolehi daripada survei seismos in situ. Julat halaju trasonik dan modulus kenyal diperolehi hasil pengukuran di makmal.
    Matched MeSH terms: Elastic Modulus
  18. AHMAD SHAHIR BIN JAMALUDIN, ABDULLAH BIN YASSIN
    Sains Malaysiana, 2013;42:1727-1733.
    Invention of milling combined laser sintering system (MLSS) is able to reduce the mould manufacturing time and improve the mould accuracy. Thus, more study is needed to increase the understanding for the laser sintered material machining characteristic to gain benefit from the invention of MLSS. This paper clarified the analysis of laser sintered material machinability with the application of Finite Element Method (FEM). Mild steel AISI1055 was applied in developing the Finite Element model in this study due to its popularity in machinability test and adequate level of data availability. 2D orthogonal cutting was employed on edge design tools with updated Lagrangian coupled thermo mechanical plane strain model. Adaptive meshing, tool edge radius and various types of friction models were assigned to obtain efficient simulations and precise cutting results. Cutting force and cutting-edge temperature estimated by Finite Element Method are validated against corresponding experimental values by previous researchers. In the study, cutting force increases when radial depth increases and lowest error acquired when the shear friction factor of 0.8 was applied. Machining simulation for laser sintered materials estimated lower cutting force compared with mild steel AISI1055 due to lower Young modulus. Higher cutting temperature estimated for machining simulation laser sintered material compared with machining simulation mild steel AISI1055 due to its low thermal conductivity.
    Matched MeSH terms: Elastic Modulus
  19. 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: Elastic Modulus
  20. Dayangku Intan Munthoub, Wan Aizan Wan Abdul Rahman
    Sains Malaysiana, 2011;40:1179-1186.
    Natural organic and abundant resources biopolymers received more attention due to their low cost, availability and degradability after usage. Cassava skin was used as natural fillers to the polyvinyl alcohol (PVA). Cassava skin/poly vinyl alcohol blends were compounded using melt extrusion twin screw extruder and test samples were prepared using the compression method. Various ratios of cassava skin and glycerol were investigated to identify suitable composition based on the water absorption and tensile properties. The water absorption of the cassava skins/PVA samples increased at higher composition of cassava skin due to their hydrophilic properties but decrease with glycerol content. The strength of the cassava skins/PVA samples increased with the higher composition of cassava skin up to 70 wt% while gradually decreased with the increasing composition of glycerol. The Young modulus increased with glycerol content but decreased with fibre loading up to 70 wt%. Elongation at break decreased with fibre loading and glycerol up to 70 wt% and 30 phr, respectively.
    Matched MeSH terms: Elastic Modulus
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