Displaying publications 1 - 20 of 35 in total

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  1. Nur S.A. Razak, Maizatul S. Shaharun, Hilmi Mukhtar, Mohd F. Taha
    Sains Malaysiana, 2013;42:515-520.
    An investigation was conducted into the nanofiltration of rhodium tris(triphenyl-phosphine) [HRh(CO)(PPh3)3] catalyst used in the hydroformylation of olefins. The large size of the catalyst (>400 Da) – relative to other components of the reaction provides the opportunity for a membrane separation based on retention of the catalyst species while permeating the solvent. The compatibility of the solvent-polyimide membrane (STARMEMTM 122 and STARMEMTM 240) combinations was assessed in terms of the membrane stability in solvent plus non-zero solvent flux at 2.0 MPa. The morphology of the membrane was studied by field emission scanning electron microscopy (FESEM). The solvent flux and membrane rejection of HRh(CO)(PPh3)3 was then determined for the catalyst-solvent-membrane combination in a dead-end pressure cell. Good HRh(CO)(PPh3)3 rejection (>0.93) coupled with good solvent fluxes (>72 L/m2h1
    at 2.0 MPa) were obtained in one of the systems tested. The effect of pressure and catalyst concentration on the solvent flux and catalyst rejection was conducted. Increasing pressure substantially improved both solvent flux and catalyst rejection, while increasing catalyst
    concentration was found to be beneficial in terms of substantial increases in catalyst rejection without significantly affecting the solvent flux.
  2. Flecia K, Mohd FA
    Med J Malaysia, 2023 May;78(3):329-335.
    PMID: 37271842
    INTRODUCTION: A patient's trust in their physician is associated with their self-reported health outcome. However, the relationship between trust in physician with therapeutic and health outcome has not been adequately explored. Therefore, this study aims to assess the level of trust in physician among type 2 diabetes mellitus patients and its association with treatment adherence and glycaemic control.

    MATERIALS AND METHODS: A cross-sectional study was conducted in Luyang Health Clinic from 1st June 2020 to 3rd September 2020. A self-interviewed questionnaire comprises of three sections; sociodemographic, Wake Forest Physician Trust Scale (WFS) and Adherence to Refills and Medications Scale (ARMS) was completed by 281 respondents. Glycaemic control is based on the latest Hba1c profile of the respondents. Descriptive and nonparametric bivariate analysis were performed using IBM SPSS version 26.

    RESULTS: The median (IQR) level of trust in physician was 43(8) out of a possible score range of 10 to 50. Trust in physician was correlated with treatment adherence (r=-0.12, p=0.048). There was no significant association between trust in physician with sociodemographic factors, which include age (p=0.33), gender (p=0.46), ethnicity (p=0.70), education level (p=0.50), and household income (p=0.37). Similarly, there was no significant association between the level of trust in physician with glycaemic control (p=0.709).

    CONCLUSION: In conclusion, trust in physician was associated with treatment adherence but not with glycaemic control. In our local context, the glycaemic control could be due to other factors. Further studies should include a multicentre population to assess other potential factors that could contribute to glycaemic control.

  3. Khamis MF, Taylor JA, Malik SN, Townsend GC
    Forensic Sci Int, 2014 Jan;234:183.e1-7.
    PMID: 24128748 DOI: 10.1016/j.forsciint.2013.09.019
    Information about the sex of individuals is important for human identification. This study was conducted to quantify classification rates of sex prediction models for Malaysians using odontometric profiles. Mesiodistal (MD) and buccolingual (BL) crown dimensions of the permanent dentition were studied in 400 young adult Malaysians, giving a total of 28 tooth size variables. The sample consisted of three major ethnic groups, the Malays, Chinese and Tamils, since the aim was to assess sex dimorphism in Malaysians as a whole. Results showed that the mesiodistal diameter of the lower canine was the most sexually dimorphic dimension in Malaysian Malays and Tamils. Univariate analyses showed that the magnitude and pattern of sex dimorphism varies between these three ethnic groups, with Malaysian Chinese and Tamils being more dimorphic than the Malaysian Malays. Stepwise discriminant functions were generated bearing in mind their application in practical forensic situations. The range of classification rates was from 70.2% to 78.5% for the composite Malaysian group, and 83.8%, 77.9%, 72.4% for Malaysian Chinese, Malays and Tamils, respectively. The 'Area Under the Receiver Operating Characteristic Curve statistics' indicated good classification rates for three prediction models obtained using a combination of all tooth size variables, mandibular teeth, and mesiodistal dimensions in the composite Malaysian group, and for all tooth size variables in each ethnic group. The present study provides strong support for the value of odontometry as an adjunct scientific method for sex prediction in human identification.
  4. Farh HMH, Eltamaly AM, Othman MF
    PLoS One, 2018;13(11):e0206171.
    PMID: 30388119 DOI: 10.1371/journal.pone.0206171
    Particle Swarm Optimization (PSO) is widely used in maximum power point tracking (MPPT) of photovoltaic (PV) energy systems. Nevertheless, this technique suffers from two main problems in the case of partial shading conditions (PSCs). The first problem is that PSO is a time invariant optimization technique that cannot follow the dynamic global peak (GP) under time variant shading patterns (SPs) and sticks to the first GP that occurs at the beginning. This problem can be solved by dispersing the PSO particles using two new techniques introduced in this paper. The two new proposed PSO re-initialization techniques are to disperse the particles upon the SP changes and the other one is upon a predefined time (PDT). The second problem is regarding the high oscillations around steady state, which can be solved by using fuzzy logic controller (FLC) to fine-tune the output power and voltage from the PV system. The new contribution of this paper is the hybrid PSO-FLC with two PSO particles dispersing techniques that is able to solve the two previous mentioned problems effectively and improve the performance of the PV system in both normal and PSCs. A detailed list of comparisons between hybrid PSO-FLC and original PSO using the two proposed methodologies are achieved. The results prove the superior performance of hybrid PSO-FLC compared to PSO in terms of efficiency, accuracy, oscillations reduction around steady state and soft tuning of the GP tracked.
  5. Upawi SN, Ahmad MF, Abu MA, Ahmad S
    J Obstet Gynaecol Res, 2020 Mar;46(3):479-484.
    PMID: 31958877 DOI: 10.1111/jog.14195
    AIM: This study is to evaluate whether unacceptable bleeding among the etonogestrel implant user could be better alleviated using combined oral contraceptive pills (COCP) or nonsteroidal anti-inflammation drugs (NSAID).

    METHODS: This is a prospective randomized study for evaluation of 84 etonogestrel implant (Implanon) users with prolonged or frequent bleeding. They were assigned to either receiving a COCP containing 20 mcg ethinyl estradiol/150 mg desogestrel for two continuous cycle or NSAID; mefenamic acid 500 mg TDS for 5 days, 21 days apart for two cycles. Bleeding pattern during the treatment was recorded and analyzed.

    RESULTS: A total of 32 women (76.2%) in COCP group and 15 women (35.7%) in NSAID group stop bleeding within 7 days after the initiation of treatment which was statistically significant (P 

  6. Kunyahamu MS, Daud A, Tengku Ismail TA, Md Tahir MF
    Cureus, 2023 Jul;15(7):e41405.
    PMID: 37546078 DOI: 10.7759/cureus.41405
    Background Mental health problems among the health workforce are a significant concern worldwide, including in Malaysia. Unfortunately, some health workforce may perceive various barriers or challenges that prevent them from seeking help. Identifying and addressing these barriers is crucial for enhancing mental health services and support. The Barriers to Access to Care Evaluation (BACE-3) questionnaire is a valuable tool that can be used for assessing these barriers among health workers. However, a validated Malay version is needed. Therefore, this study aims to translate, adapt, and validate the original version of Barriers to Access to Care Evaluation (BACE-3) into the Malay version (MBACE). Methods A rigorous process of translation and adaptation was followed to develop the Malay version of the BACE-3 questionnaire (MBACE). A cross-sectional study was conducted to assess the psychometric properties of the questionnaire, with purposive sampling employed to recruit 188 participants from various job categories, including doctors, nurses, pharmacists, and non-clinical staff, such as health assistants and clerks. The analysis was conducted using the R software version 4.2.2 (R Foundation, Vienna, Austria). Construct validity was determined using confirmatory factor analysis (CFA). To assess the convergent validity, internal consistency, and reliability of the instrument, measures such as the average variance extracted (AVE), composite reliability (CR), and Cronbach's alpha values were calculated. Results During the CFA process, two items with a factor loading less than 0.5 (items 15 and 16) were removed to improve the convergent validity and model fit. The CFA results revealed that the 2-factor model MBACE had good construct validity (root mean square error of approximation (RMSEA) = 0.053; comparative fit index (CFI) = 0.939; Tucker-Lewis fit index (TLI) = 0.934). The internal consistency was supported by Cronbach's alpha values ranging from 0.92 to 0.94 for the stigma factor and non-stigma factor. The average variance extracted (AVE) and composite reliability (CR) values further supported the questionnaire's reliability and convergent validity. Conclusion The translated and adapted 28-item MBACE questionnaire is a valid and reliable tool for assessing the barrier to seeking professional mental health care among the Malaysian health workforce. This instrument has the potential to aid in the development of targeted interventions to promote mental health help-seeking behavior and enhance the well-being of the Malaysian health workforce.
  7. Mohd Razip Wee MF, Dehzangi A, Bollaert S, Wichmann N, Majlis BY
    PLoS One, 2013;8(12):e82731.
    PMID: 24367548 DOI: 10.1371/journal.pone.0082731
    A multi-gate n-type In₀.₅₃Ga₀.₄₇As MOSFET is fabricated using gate-first self-aligned method and air-bridge technology. The devices with different gate lengths were fabricated with the Al2O3 oxide layer with the thickness of 8 nm. In this letter, impact of gate length variation on device parameter such as threshold voltage, high and low voltage transconductance, subthreshold swing and off current are investigated at room temperature. Scaling the gate length revealed good enhancement in all investigated parameters but the negative shift in threshold voltage was observed for shorter gate lengths. The high drain current of 1.13 A/mm and maximum extrinsic transconductance of 678 mS/mm with the field effect mobility of 364 cm(2)/Vs are achieved for the gate length and width of 0.2 µm and 30 µm, respectively. The source/drain overlap length for the device is approximately extracted about 51 nm with the leakage current in order of 10(-8) A. The results of RF measurement for cut-off and maximum oscillation frequency for devices with different gate lengths are compared.
  8. Das S, Abd Latiff A, Suhaimi FH, Othman FB, Yahaya MF, Ahmad F, et al.
    Bratisl Lek Listy, 2008;109(11):520-4.
    PMID: 19205565
    The occipital sinus (OS) lies in the attached margin of the faix cerebelli in the internal occipital crest of the occipital bone. The OS extends from the foramen magnum to the confluence of sinuses. Standard textbooks and research reports do not describe in detail any variation in the groove for the occipital sinus.
  9. Aziz SB, Hamsan MH, Kadir MFZ, Karim WO, Abdullah RM
    Int J Mol Sci, 2019 Jul 09;20(13).
    PMID: 31323971 DOI: 10.3390/ijms20133369
    Solid polymer blend electrolyte membranes (SPBEM) composed of chitosan and dextran with the incorporation of various amounts of lithium perchlorate (LiClO4) were synthesized. The complexation of the polymer blend electrolytes with the salt was examined using FTIR spectroscopy and X-ray diffraction (XRD). The morphology of the SPBEs was also investigated using field emission scanning electron microscopy (FESEM). The ion transport behavior of the membrane films was measured using impedance spectroscopy. The membrane with highest LiClO4 content was found to exhibit the highest conductivity of 5.16 × 10-3 S/cm. Ionic (ti) and electronic (te) transference numbers for the highest conducting electrolyte were found to be 0.98 and 0.02, respectively. Electrochemical stability was estimated from linear sweep voltammetry and found to be up to ~2.3V for the Li+ ion conducting electrolyte. The only existence of electrical double charging at the surface of electrodes was evidenced from the absence of peaks in cyclic voltammetry (CV) plot. The discharge slope was observed to be almost linear, confirming the capacitive behavior of the EDLC. The performance of synthesized EDLC was studied using CV and charge-discharge techniques. The highest specific capacitance was achieved to be 8.7 F·g-1 at 20th cycle. The efficiency (η) was observed to be at 92.8% and remained constant at 92.0% up to 100 cycles. The EDLC was considered to have a reasonable electrode-electrolyte contact, in which η exceeds 90.0%. It was determined that equivalent series resistance (Resr) is quite low and varies from 150 to 180 Ω over the 100 cycles. Energy density (Ed) was found to be 1.21 Wh·kg-1 at the 1st cycle and then remained stable at 0.86 Wh·kg-1 up to 100 cycles. The interesting observation is that the value of Pd increases back to 685 W·kg-1 up to 80 cycles.
  10. Aziz SB, Brza MA, Hamsan EMADMH, Hadi JM, Kadir MFZ, Abdulwahid RT
    Molecules, 2020 Oct 01;25(19).
    PMID: 33019618 DOI: 10.3390/molecules25194503
    Plasticized magnesium ion conducting polymer blend electrolytes based on chitosan (CS): polyvinyl alcohol (PVA) was synthesized with a casting technique. The source of ions is magnesium triflate Mg(CF3SO3)2, and glycerol was used as a plasticizer. The electrical and electrochemical characteristics were examined. The outcome from X-ray diffraction (XRD) examination illustrates that the electrolyte with highest conductivity exhibits the minimum degree of crystallinity. The study of the dielectric relaxation has shown that the peak appearance obeys the non-Debye type of relaxation process. An enhancement in conductivity of ions of the electrolyte system was achieved by insertion of glycerol. The total conductivity is essentially ascribed to ions instead of electrons. The maximum DC ionic conductivity was measured to be 1.016 × 10-5 S cm-1 when 42 wt.% of plasticizer was added. Potential stability of the highest conducting electrolyte was found to be 2.4 V. The cyclic voltammetry (CV) response shows the behavior of the capacitor is non-Faradaic where no redox peaks appear. The shape of the CV response and EDLC specific capacitance are influenced by the scan rate. The specific capacitance values were 7.41 F/g and 32.69 F/g at 100 mV/s and 10 mV/s, respectively. Finally, the electrolyte with maximum conductivity value is obtained and used as electrodes separator in the electrochemical double-layer capacitor (EDLC) applications. The role of lattice energy of magnesium salts in energy storage performance is discussed in detail.
  11. Sanusi SY, Jamaludin SA, Al-Batayneh OB, Sinor MZ, Khamis MF
    Int J Clin Pediatr Dent, 2020 6 26;13(1):79-84.
    PMID: 32581485 DOI: 10.5005/jp-journals-10005-1712
    Aim: This 3-year retrospective case series evaluated the clinical and radiographic outcome of ferric sulfate and formocresol pulpotomy in primary molar teeth in a dental teaching hospital in Malaysia.

    Materials and methods: Clinical and radiographic records of all pediatric patients who had pulpotomy of primary molar teeth between July 2005 and October 2008 were evaluated. A total of 55 pulpotomized primary molars were observed. Clinical assessments were carried out during the second visit to assess the presence of sinus tract, gingival swelling, excessive tooth mobility, tenderness to percussion, and abnormal exfoliation of the treated teeth. Periapical radiographs were reviewed for evidence of pathologic root resorption, radicular and/or periapical radiolucency, and abnormal pulp canal calcification. Treatments were regarded as failure in the presence of one or more of the above clinical and/or radiographic signs and symptoms.

    Results: Of 55 pulpotomized teeth, 26 (47.3%) remained free from any clinical signs and symptoms and 48 (87.3%) showed no pathological radiographic findings. The clinical success rates of ferric sulfate and formocresol pulpotomy were 44.4% and 60.0%, respectively, whereas the radiographic success rates of ferric sulfate and formocresol pulpotomy were 86.7% and 90.0%, respectively. Although teeth treated with formocresol had higher both clinical and radiographic success rates compared with those treated with ferric sulfate, it was not statistically significant.

    Conclusion: The clinical success rates of pulpotomy were lower compared with radiographic success rates. Ferric sulfate is an alternative to formocresol; however, the use of both agents in the dental undergraduate teaching at Universiti Sains Malaysia can still be recommended.

    Clinical significance: Formocresol and ferric sulfate are advocated as pulpotomy agents in primary molar teeth since both agents showed comparable clinical and radiographic success rates.

    How to cite this article: Sanusi SY, Jamaludin SA, Al-Batayneh OB, et al. Fate of Pulpotomized Teeth in Pediatric Patients: A 3-year Case Series in a Malaysian Dental Teaching Hospital. Int J Clin Pediatr Dent 2020;13(1):79-84.

  12. Chia LL, Jantan I, Chua KH, Lam KW, Rullah K, Aluwi MF
    Front Pharmacol, 2016;7:291.
    PMID: 27625609 DOI: 10.3389/fphar.2016.00291
    Tocotrienols (T3) are well-known for their antioxidant properties besides showing therapeutic potential in clinical complications such as hyperlipidemia induced by diabetes. The aim of this study was to determine the effects of δ-T3, γ-T3, and α-T3 on insulin secretion-associated genes expression of rat pancreatic islets in a dynamic culture. Pancreatic islets freshly isolated from male Wistar rats were treated with T3 for 1 h at 37°C in a microfluidic system with continuous operation. The cells were collected for total RNA extraction and reverse-transcribed, followed by measurement of insulin secretion-associated genes expression using quantitative real-time polymerase chain reaction. Molecular docking experiments were performed to gain insights on how the T3 bind to the receptors. Short-term exposure of δ- and γ-T3 to pancreatic β cells in a stimulant glucose condition (16.7 mM) significantly regulated preproinsulin mRNA levels and insulin gene transcription. In contrast, α-T3 possessed less ability in the activation of insulin synthesis level. Essentially, potassium chloride (KCl), a β cell membrane depolarising agent added into the treatment further enhanced the insulin production. δ- and γ-T3 revealed significantly higher quantitative expression in most of the insulin secretion-associated genes groups containing 16.7 mM glucose alone and 16.7 mM glucose with 30 mM KCl ranging from 600 to 1200 μM (p < 0.05). The findings suggest the potential of δ-T3 in regulating insulin synthesis and glucose-stimulated insulin secretion through triggering pathway especially in the presence of KCl.
  13. Abu Bakar FI, Abu Bakar MF, Rahmat A, Abdullah N, Sabran SF, Endrini S
    Front Pharmacol, 2018;9:261.
    PMID: 29628890 DOI: 10.3389/fphar.2018.00261
    Gout is a type of arthritis that causes painful inflammation in one or more joints. In gout, elevation of uric acid in the blood triggers the formation of crystals, causing joint pain. Malaysia is a mega-biodiversity country that is rich in medicinal plants species. Therefore, its flora might offer promising therapies for gout. This article aims to systematically review the anti-gout potential of Malaysian medicinal plants. Articles on gout published from 2000 to 2017 were identified using PubMed, Scopus, ScienceDirect, and Google Scholar with the following keyword search terms: "gout," "medicinal plants," "Malaysia," "epidemiology," "in vitro," and "in vivo." In this study, 85 plants were identified as possessing anti-gout activity. These plants had higher percentages of xanthine oxidase inhibitory activity (>85%); specifically, the Momordica charantia, Chrysanthemum indicum, Cinnamomum cassia, Kaempferia galanga, Artemisia vulgaris, and Morinda elliptica had the highest values, due to their diverse natural bioactive compounds, which include flavonoids, phenolics, tannin, coumarins, luteolin, and apigenin. This review summarizes the anti-gout potential of Malaysian medicinal plants but the mechanisms, active compounds, pharmacokinetics, bioavailability, and safety of the plants still remain to be elucidated.
  14. Tsan SEH, Lim SM, Abidin MFZ, Ganesh S, Wang CY
    Anesth Analg, 2020 07;131(1):210-219.
    PMID: 31348051 DOI: 10.1213/ANE.0000000000004349
    BACKGROUND: Approximately half of all difficult tracheal intubations (DTIs) are unanticipated; hence, proper positioning during intubation is critical to increase the likelihood of success. The bed-up-head-elevated (BUHE) intubation position has been shown to improve laryngeal view, reduce airway complications, and prolong safe apneic time during intubation. In this study, we sought to determine whether the BUHE intubation position is noninferior to Glidescope (GLSC)-assisted intubation with regard to laryngeal exposure.

    METHODS: A total of 138 American Society of Anesthesiologists (ASA) I to III patients were randomly assigned into 2 groups and underwent baseline laryngoscopy in the sniffing position. Group BUHE patients (n = 69) were then intubated in the BUHE position, while group GLSC patients (n = 69) were intubated using GLSC laryngoscopy. Laryngeal exposure was measured using Percentage of Glottic Opening (POGO) score and Cormack-Lehane (CL) grading, and noninferiority will be declared if the difference in mean POGO scores between both groups do not exceed -15% at the lower limit of a 98% confidence interval (CI). Secondary outcomes measured included time required for intubation (TRI), number of intubation attempts, use of airway adjuncts, effort during laryngoscopy, and complications during intubation.

    RESULTS: Mean POGO score in group BUHE was 80.14% ± 22.03%, while in group GLSC it was 86.45% ± 18.83%, with a mean difference of -6.3% (98% CI, -13.2% to 0.6%). In both groups, there was a significant improvement in mean POGO scores when compared to baseline laryngoscopy in the sniffing position (group BUHE, 25.8% ± 4.7%; group GLSC, 30.7% ± 6.8%) (P < .0001). The mean TRI was 36.23 ± 14.41 seconds in group BUHE, while group GLSC had a mean TRI of 44.33 ± 11.53 seconds (P < .0001). In patients with baseline CL 3 grading, there was no significant difference between mean POGO scores in both groups (group BUHE, 49.2% ± 19.6% versus group GLSC, 70.5% ± 29.7%; P = .054).

    CONCLUSIONS: In the general population, BUHE intubation position provides a noninferior laryngeal view to GLSC intubation. The laryngeal views obtained in both approaches were superior to the laryngeal view obtained in the sniffing position. In view of the many advantages of the BUHE position for intubation, the lack of proven adverse effects, the simplicity, and the cost-effectiveness, we propose that clinicians should consider the BUHE position as the standard intubation position for the general population.

  15. Sadiq NM, Abdulwahid RT, Aziz SB, Woo HJ, Kadir MFZ
    Int J Biol Macromol, 2024 Apr;265(Pt 1):130751.
    PMID: 38471616 DOI: 10.1016/j.ijbiomac.2024.130751
    The challenge in front of EDLC device is their low energy density compared to their battery counter parts. In the current study, a green plasticized nanocomposite sodium ion conducting polymer blend electrolytes (PNSPBE) was developed by incorporating plasticized Chitosan (CS) blended with polyvinyl alcohol (PVA), doped with NaBr salt with various concentration of CaTiO3 nanoparticles. The most optimized PNSPBE film was subsequently utilized in an EDLC device to evaluate its effectiveness both as an electrolyte and a separator. Structural and morphological changes were assessed using XRD and SEM techniques. The PNSPBE film demonstrated a peak ionic conductivity of 9.76×10-5 S/cm, as determined through EIS analysis. The dielectric and AC studies provided further confirmation of structural modifications within the sample. Both TNM and LSV analyses affirmed the suitability of the prepared electrolyte for energy device applications, evidenced by its adequate ion transference number and an electrochemical potential window of 2.86 V. Electrochemical properties were assessed via CV and GCD techniques, confirming non-Faradaic ion storage, indicated by the rectangular CV pattern at low scan rates. The parameters associated with the designed EDLC device including specific capacitance, ESR, power density (1950 W/kg) and energy density (12.3 Wh/kg) were determined over 1000 cycles.
  16. B Aziz S, Brza MA, Brevik I, Hafiz MH, Asnawi ASFM, Yusof YM, et al.
    Polymers (Basel), 2020 Sep 16;12(9).
    PMID: 32947829 DOI: 10.3390/polym12092103
    This research paper investigates the electrochemical performance of chitosan (CS): dextran (DX) polymer-blend electrolytes (PBEs), which have been developed successfully with the incorporation of ammonium hexafluorophosphate (NH4PF6). X-ray diffraction (XRD) analysis indicates that the plasticized electrolyte system with the highest value of direct current (DC) ionic conductivity is the most amorphous system. The glycerol addition increased the amorphous phase and improved the ionic dissociation, which contributed to the enhancement of the fabricated device's performance. Transference number analysis (TNM) has shown that the charge transport process is mainly by ions rather than electrons, as tion = 0.957. The CS:DX:NH4PF6 system was found to decompose as the voltage goes beyond 1.5 V. Linear sweep voltammetry (LSV) revealed that the potential window for the most plasticized system is 1.5 V. The fabricated electrochemical double-layer capacitor (EDLC) was analyzed with cyclic voltammetry (CV) and charge-discharge analysis. The results from CV verify that the EDLC in this work holds the characteristics of a capacitor. The imperative parameters of the fabricated EDLC such as specific capacitance and internal resistance were found to be 102.9 F/g and 30 Ω, respectively. The energy stored and power delivered by the EDLC were 11.6 Wh/kg and 2741.2 W/kg, respectively.
  17. Aziz SB, Abdulwahid RT, Hamsan MH, Brza MA, Abdullah RM, Kadir MFZ, et al.
    Molecules, 2019 Sep 27;24(19).
    PMID: 31569650 DOI: 10.3390/molecules24193508
    In this report, a facile solution casting technique was used to fabricate polymer blend electrolytes of chitosan (CS):poly (ethylene oxide) (PEO):NH4SCN with high electrochemical stability (2.43V). Fourier transform infrared (FTIR) spectroscopy was used to investigate the polymer electrolyte formation. For the electrochemical property analysis, cyclic voltammetry (CV), linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS) techniques were carried out. Referring to the FTIR spectra, a complex formation between the added salt and CS:PEO was deduced by considering the decreasing and shifting of FTIR bands intensity in terms of functional groups. The CS:PEO:NH4SCN electrolyte was found to be electrochemically stable as the applied voltage linearly swept up to 2.43V. The cyclic voltammogram has presented a wide potential window without showing any sign of redox peaks on the electrode surface. The proved mechanisms of charge storage in these fabricated systems were found to be double layer charging. The EIS analysis showed the existence of bulk resistance, wherein the semicircle diameter decreased with increasing salt concentration. The calculated maximum DC conductivity value was observed to be 2.11 × 10-4 S/cm for CS:PEO incorporated with 40 wt% of NH4SCN salt. The charged species in CS:PEO:NH4SCN electrolytes were considered to be predominantly ionic in nature. This was verified from transference number analysis (TNM), in which ion and electron transference numbers were found to be tion = 0.954 and tel = 0.045, respectively. The results obtained for both ion transference number and DC conductivity implied the possibility of fabricating electrolytes for electrochemical double layer capacitor (EDLC) device application. The specific capacitance of the fabricated EDLC was obtained from the area under the curve of the CV plot.
  18. Brza MA, B Aziz S, Anuar H, Dannoun EMA, Ali F, Abdulwahid RT, et al.
    Polymers (Basel), 2020 Aug 23;12(9).
    PMID: 32842522 DOI: 10.3390/polym12091896
    In the present work, a novel polymer composite electrolytes (PCEs) based on poly(vinyl alcohol) (PVA): ammonium thiocyanate (NH4SCN): Cd(II)-complex plasticized with glycerol (Gly) are prepared by solution cast technique. The film structure was examined by XRD and FTIR routes. The utmost ambient temperature DC ionic conductivity (σDC) of 2.01 × 10-3 S cm-1 is achieved. The film morphology was studied by field emission scanning electron microscopy (FESEM). The trend of σDC is further confirmed with investigation of dielectric properties. Transference numbers of ions (tion) and electrons (tel) are specified to be 0.96 and 0.04, respectively. Linear sweep voltammetry (LSV) displayed that the PCE potential window is 2.1 V. The desired mixture of activated carbon (AC) and carbon black was used to fabricate the electrodes of the EDLC. Cyclic voltammetry (CV) was carried out by sandwiching the PCEs between two carbon-based electrodes, and it revealed an almost rectangular shape. The EDLC exhibited specific capacitance, energy density, and equivalent series resistance with average of 160.07F/g, 18.01Wh/kg, and 51.05Ω, respectively, within 450 cycles. The EDLC demonstrated the initial power density as 4.065 × 103 W/Kg.
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