Review: Direct ethanol fuel cells Kamarudin, M.Z.F.; Kamarudin, S.K.; Masdar, M.S. ...
International journal of hydrogen energy,
07/2013, Volume:
38, Issue:
22
Journal Article, Conference Proceeding
Peer reviewed
Direct ethanol fuel cells have attracted much attention recently in the search for alternative energy resources. As an emerging technology, direct ethanol fuel cells have many challenges that need to ...be addressed. Many improvements have been made to increase the performance of direct ethanol fuel cells, and there are great expectations for their potential. However, many improvements need to be made in order to enhance the potential of direct ethanol fuel cells in the future. This paper addresses the challenges and the developments of direct ethanol fuel cells at present. It also presents the applications of DEFC.
► Direct ethanol fuel cells have attracted much attention recently. ► As an emerging technology, direct ethanol fuel cells have many challenges and improvements. ► This paper addresses the challenges and the developments of direct ethanol fuel cells at present. ► It also presents the application of DEFC.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Fuel cells were an important technology that could be used for a variety of power applications. The direct methanol fuel cell (DMFC) was a promising candidate for powering portable electronic devices ...such as laptops, digital cameras and cell phones. Compared with conventional batteries, DMFCs could provide a higher power density with a longer lifetime and almost instant recharging. However, many issues related to the design, fabrication and operation of miniaturised DMFC power systems remain unsolved. Fuel delivery was a key issue in determining the performance of a DMFC. To achieve the desired performance, an efficient fuel delivery system was required to provide an adequate amount of fuel for consumption and to remove the carbon dioxide generated in the fuel-cell devices. This paper presented a detailed description of various fuel flow-field designs for DMFCs and their respective advantages. This paper also discussed the current approaches and challenges in existing fuel delivery and fuel storage systems, including active and passive DMFCs and micro-fluidic systems. The commercialisation of DMFCs with storage was presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The objective of this study is to investigate the significant interaction effects of design parameters on the methanol flux of a single 4.84 cm2 Direct Methanol Fuel Cell (DMFC). This study uses 24 ...full-factorial designs, a factorial arrangement with four factors at two-levels and one center point. The following factors are considered in this study: the inlet diameter of the inlet flow, the direction of the flow, the fuel cell orientation and the height of the second storage vessel. The inlet diameters of the inlet flow under consideration are 1.5, 2.38 and 4 mm. The directions of the flow are bottom and top. The orientation is selected between vertical and horizontal. The height of the second storage tank varies from 50 mm to 70 mm, in 10 mm intervals. The results show that the direction of the flow has the most significant effect on the greatest methanol flux, and the next most significant factor is the orientation, while the inlet diameter of the inflow and the height of the second storage vessel play only minor roles. However, the interaction between the inlet diameter of the inflow and the height of second storage tank shows a significant effect that must be considered. The results agree with Computational Fluid Dynamics (CFD) simulation results and the literature.
•This study investigates the effects of design parameters on the methanol flux in DMFC.•The results show that the direction and orientation have the most significant effects on methanol flux.•The experimental results agree with the Computational Fluid Dynamics (CFD) simulation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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► A low cost bivalve shell treated zea mays L. husk leaf biosorbent was developed. ► BS acts as a strong alkali pretreatment agent for ZHL. ► BS-ZHL enhanced the malachite green ...adsorption up to 81.5mgg−1 (qmax). ► The experimental data agrees with the Langmuir isotherm model. ► The adsorption was controlled by the physisorption process.
In this work, two low-cost wastes, bivalve shell (BS) and Zea mays L. husk leaf (ZHL), were investigated to adsorb malachite green (MG) from aqueous solutions. The ZHL was treated with calcined BS to give the BS-ZHL, and its ability to adsorb MG was compared with untreated ZHL, calcined BS and Ca(OH)2-treated ZHL under several different conditions: pH (2–8), adsorbent dosage (0.25–2.5gL−1), contact time (10–30min), initial MG concentration (10–200mgL−1) and temperature (303–323K). The equilibrium studies indicated that the experimental data were in agreement with the Langmuir isotherm model. The use of 2.5gL−1 BS-ZHL resulted in the nearly complete removal of 200mgL−1 of MG with a maximum adsorption capacity of 81.5mgg−1 after 30min of contact time at pH 6 and 323K. The results indicated that the BS-ZHL can be used to effectively remove MG from aqueous media.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Coronavirus disease 2019 (COVID-19) is an infectious disease caused by a novel coronavirus, now widely known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has caused 3 major ...pandemic waves in Malaysia. We aimed to identify the warning signs as indicators that predict the progression of disease.
This is a retrospective cohort study of adult patients more than 12 years of age presenting with laboratory-confirmed COVID-19 admitted in three separate hospitals around the country.
Of the 228 patients initially admitted with mild illness, 47 had progressed requiring oxygen. The median time from admission to deterioration was 3 days (IQR 2 - 5). Age more than ≥50years old (median age = 42.5, IQR = 28.8 - 57.0), higher temperature (mean = 37.3, IQR 36.8 - 38.0), MEWS score >3 (9, 19.1%), Neutrophil-to-lymphocyte ratio (NLR) >3.13 , (18, 38.3%) C-reactive protein (CRP) >5. (12, 27.3%), multiple zonal involvement on the chest radiography on admission (2, IQR 1-3) were more common in the deteriorated group on admission. On multivariate analysis, multiple comorbidities (HR = 7.40, 95 percent CI 2.58-21.2, p0.001), presence of persistent fever (HR = 2.88, 95 percent CI 1.15 - 7.2, p = 0.024), MEWS scoring >3 (HR of 6.72 ;95 percent CI 2.81-16.0, p0.001) were associated with progression to severe illness.
In our cohort, we found that several factors were associated with the severity of COVID19. Early detection of these factors could correctly identify patients who need more intensive monitoring, and early referral for ICU care.
Aim
The 36‐month Long‐Term Research Grant Scheme project: Towards Usual Aging – Neuroprotective Model for Healthy Longevity among Malaysian Elderly was designed to address multidimensional aspects ...including psychosocial, biophysical health, nutrition and dietary pattern, and auditory and visual function to highlight the magnitude of these associations in a single study.
Methods
A total of 2322 respondents aged ≥60 years were recruited at baseline using the multistage sampling method, followed up at 18 months and 36 months.
Results
Response rates at baseline, 18 months and 36 months were 87.8%, 77.3% and 67.1%, respectively. At baseline, the prevalence of successful aging, usual aging and mild cognitive impairment was 11%, 73% and 16%, respectively. The prevalence of single and multimorbidity at baseline were 25.9% and 50.3%, respectively. The incidence rates of mild cognitive impairment at 18 months and 36 months were 6.5 and 5.6 per 100 person‐years. The incidence rates of multimorbidity at 18 months and 36 months were 23.7 and 21.5 per 100 person‐years, respectively.
Conclusions
The Long‐Term Research Grant Scheme project: Towards Usual Aging study provides an opportunity to investigate the interactions between wide ranges of aspects of the older population in a nationally representative sample of the older population. Geriatr Gerontol Int 2019; 19: 233–239.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Nowadays, the quality of air in the environment has been impacted by the industry. It is important to make sure our ambient air especially in an indoor environment is clean from contaminating ...particles or harmful gases. Therefore, the air quality inside the indoor environment should be monitored regularly. One of the major problems, when a particular environment has been contaminated by harmful gases, is finding the source of the emission. If the indoor environment has been contaminated by a harmful source it should be instantly localized and eliminated to prevent severe casualties. In this paper, we propose the utilization of synthetic data generated by the Computational Fluid Dynamic (CFD) approach to train the Deep Neural Network (DNN) model called CFD-DNN to perform gas source localization in an indoor environment. The model is capable to locate the contaminated source within a small area of an indoor environment. A total of 361 datasets with different locations of contaminated source release have been obtained using the CFD approach. The obtained dataset was divided into training and testing datasets. The training dataset was used for the model training process while the testing dataset is fed into the model to test model reliability to predict the gas source location. The Euclidian distance equation was used to measure the distance error between the actual and predicted location of the source. The result shows that the model is capable to locate the gas source within a minimum and maximum error of 0.03m to 0.46m respectively.
Bamboo is a sustainable and cost-effective alternative to traditional construction materials. Despite the fact that three species are well known for structural applications, namely Dendrocalamus ...asper, Gigantochloa scortechinii, and Gigantochloa levis, the scientific data for their mechanical characterization is scarcely available and widely dispersed. In addition, a systematic literature review appraising the study advancement of mechanical characterization of bamboo had been unavailable. This paper bridges this gap by conducting a systematic literature review (SLR) of the available literature of mechanical characterization of bamboo pole. A total of 54 relevant articles were retrieved from Scopus and snowballing and then put forward through bibliometric analysis using VOSviewer. The results showed that the distribution of data for physical and mechanical characterization of aforementioned species was scattered due to the different location (origin), age, and initial moisture content recorded during empirical work among the researchers. This review’s importance and distinctiveness lie in its synthesis of the existing literature on bamboo mechanical characterization. The findings provide a point of reference for both academia and industry by bridging the scarcity of current bamboo engineering data and outlining future possibilities for bamboo research in the building and construction domain.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
A reflectarray antenna consisting of asymmetrical patch elements is proposed, which is capable of producing dual linear and dual circular polarized operation at 26 GHz frequency. The main purpose of ...this design is to support four different polarizations using the same patch element. The proposed reflectarray has a single layer configuration with a linearly polarized feed and circular ring slots in the ground plane. Asymmetric patch element is designed from a square patch element by tilting its one vertical side to some optimized inclination. A wide reflection phase range of 600° is obtained with the asymmetric patch element during unit cell measurements. A 332 element circular aperture reflectarray is designed with the proposed configuration and experimentally validated with a linearly polarized prime feed configuration. Two different orientations of mirror and non-mirror asymmetric patch elements on the surface of reflectarray are analyzed. Dual linear polarization is obtained with the mirror orientation of the asymmetric patch elements on the surface of reflectarray. Alternatively, asymmetric patch elements without mirror orientation are demonstrated to produce dual circular polarization with the same linearly polarized feed. A maximum measured gain of 24.4 dB and 26.1 dB is achieved for dual linear and dual circular polarization, respectively. Their respective measured efficiencies are 28% and 41.3%, which are supported by a maximum −3 dB gain bandwidth of 13.8% and 11.5%. The circular polarization operation of the reflectarray is also supported by a 6 dB axial ratio bandwidth of 9.2%. The proposed asymmetric patch reflectarray antenna with polarization diversity, wide bandwidth and high gain is suitable to be used in many high frequency applications of 5G communication.
Magnetic Data Acquisition System (MAGDAS) is a magnetometer initiated by the International Center for Space Weather Science and Education in Kyushu University, Japan, to study space weather. The ...latest of real-time Magnetic Data Acquisition System/Circum-pan Pacific Magnetometer Network was successfully installed at the East Coast Environmental Research Institute in Universiti Sultan Zainal Abidin, Terengganu, Malaysia, by Kyushu University. This is the fifth magnetometer under the MAGDAS network (geographic latitude and longitude: 5.23°, 103.04° and geomagnetic latitude and longitude: − 4.21°, 175.91°). In this study, the results of data plot obtained at Terengganu (TRE) station were shown to have reliable patterns of geomagnetic elements. The amplitude variations for each component were also proximate with other stations and a standard model. This study compared MAGDAS-II data for the H component with solar wind data (input energy, IMF, dynamic pressure and speed).
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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