Biodiesel Production from Palm Oil over Potassium Based Montmorillonite-K10 (MK10) Clay Catalyst

The heterogeneous catalyst Montmorillonite MK10 clay (MK10) and potassium modified MK10 were prepared for biodiesel production through transesterification process. The catalyst MK10 was modified with different salt of potassium such as Potassium Hydroxide (KOH), Potassium Nitrate (KNO3), and Potassium Carbonate (K2CO3). These prepared catalyst then tested for activity of biodiesel production through transesterification reaction. The process variable used is the same for each catalyst as to check which gives higher yield at the same operating condition. Operating parameters used for this experiment are: catalyst 2wt%., Temperature at 60℃ , methanol to oil molar ratio 10:1, and reaction time of 2 hours using the same alcohol and feed stock which are methanol and palm oil. The optimum yield of fatty acid methyl ester were found to be potassium hydroxide (KOH). Based on the results obtained, the catalyst potassium hydroxide based Montmorillonite K10 clay catalyst (KOH/MK10) will be producing higher yield compare to potassium carbonate (KCO3/MK10), and potassium nitrate (KNO3/MK10) catalyst with at temperature of 60℃, 10:1 of methanol to oil ratio, 2 hours reaction time and 2 weight % of catalyst used. In addition, 5.0% of KOH metal loading on the MK-10 clay gives better performance while the temperature tested on catalyst, 60℃ is the best operating temperature giving out better performance for modified KOH/MK10 catalyst compare to other temperature which is 30℃, 50℃ and 70℃ tested. In term of stability of the catalyst, modified KOH/MK10 clay catalyst can only be used a few times and replaced with new catalyst as the performance of the catalyst dropped with respect of the cycle

Simulation On Performance Of Gan-Based Light Emitting Diodes With Varied Geometry And Contacts Design

The main objective of this research is to minimize the current crowding problem inside GaN-based Light Emitting Diode (LED). Self heating effects and low radiative recombination are among the consequences that restrict the true potential of high electrical and optical performance of LED. By using device simulator, ISE TCAD as a tool, current crowding problem is investigated with varied geometries of lateral p-i-n LED structure. The effective lateral current paths between two contacts are examined by fixing the position of n-contact while p-contact position is varied on p-layer. This work revealed that the location of p-contact at the centre of p-type layer was the effective length of lateral current path where better current distribution and low series resistance were obtained due to the symmetry of current spreading length for carrier movement. Based on the effective lateral current path, the effect of contact geometrics showed that square shape contact out-performed other shape, namely hexagonal, octagonal and circular. The square shape which has largest contact periphery area helped current to spread uniformly and reduces the potential of current crowding at the n-contact due to lower resistance along the current path

Flow and heat transfer analysis on spiral counter flow heat recirculating burner

In order to establish a performance characterization of spiral counter flow heat recirculating burner, an understanding of the chemical kinetics, heat transfer and flow dynamics aspects of the combustor needs to be developed. Research would be focusing on the micro-scaled square spiral counter flow configuration which is also known as the “Swiss roll� micro-combustor with propane-air mixture as the case study. A two-dimensional Computational Fluid Dynamics (CFD) with propane-air premixed stoichiometric numerical based model is being adopted and focus of the study would be in observing the thermal characteristic (i.e. heat recirculation rate) of the combustor. This is the parameter that characterizes the preheat energy obtained by the incoming reactants through combustion process and its high energy postcombustion products. The performance of the combustor with respect to the thermal characteristic is being analyzed at a range of 40<Re<1000 steady, laminar and incompressible fluid flow velocity profile. In addition, a parametric study on identifying the effect of different geometrical aspect ratio between channel wall thickness to channel width is also being envisaged. Analysis has shown that a heat recirculation method has managed to produce an excess enthalpy flame beyond the adiabatic flame temperature which leads towards extending the limitation of the combustion process feasibility in a miniaturization of a combustor system

Biodiesel Production from Palm Oil over Potassium Based Montmorillonite-K10 (MK10) Clay Catalyst

The heterogeneous catalyst Montmorillonite MK10 clay (MK10) and potassium modified MK10 were prepared for biodiesel production through transesterification process. The catalyst MK10 was modified with different salt of potassium such as Potassium Hydroxide (KOH), Potassium Nitrate (KNO3), and Potassium Carbonate (K2CO3). These prepared catalyst then tested for activity of biodiesel production through transesterification reaction. The process variable used is the same for each catalyst as to check which gives higher yield at the same operating condition. Operating parameters used for this experiment are: catalyst 2wt%., Temperature at 60℃ , methanol to oil molar ratio 10:1, and reaction time of 2 hours using the same alcohol and feed stock which are methanol and palm oil. The optimum yield of fatty acid methyl ester were found to be potassium hydroxide (KOH). Based on the results obtained, the catalyst potassium hydroxide based Montmorillonite K10 clay catalyst (KOH/MK10) will be producing higher yield compare to potassium carbonate (KCO3/MK10), and potassium nitrate (KNO3/MK10) catalyst with at temperature of 60℃, 10:1 of methanol to oil ratio, 2 hours reaction time and 2 weight % of catalyst used. In addition, 5.0% of KOH metal loading on the MK-10 clay gives better performance while the temperature tested on catalyst, 60℃ is the best operating temperature giving out better performance for modified KOH/MK10 catalyst compare to other temperature which is 30℃, 50℃ and 70℃ tested. In term of stability of the catalyst, modified KOH/MK10 clay catalyst can only be used a few times and replaced with new catalyst as the performance of the catalyst dropped with respect of the cycle

Ketokohan Sheikh Abdul Qadir al-Mandili dalam bidang hadis

Sheikh Abdul Qadir al-Mandili merupakan ulama terkenal di alam Melayu Nusantara. Ketokohan beliau terserlah melalui penghasilan karya penulisannya dalam pelbagai disiplin ilmu. Beliau boleh dikategorikan sebagai seorang ulama yang produktif dalam menghasilkan karya. Selain itu, keizinan yang diperolehi beliau untuk menyampaikan ilmu dalam al-Masjid al-Haram yang merupakan pusat ilmu pada waktu tersebut membuktikan kealiman serta ketokohan beliau diperakui. Oleh yang demikian, kajian ini akan mengetengahkan ketokohan Sheikh Abdul Qadir al-Mandili di dalam ilmu keislaman dengan difokuskan kepada ilmu hadis. Kajian itu bertujuan untuk melihat sejauh mana penguasaan beliau dalam ilmu tersebut. Perbincangan mengenai penggunaan, pemilihan serta penulisan hadis dalam karya-karya beliau menjadi fokus utama kajian ini. Reka bentuk kajian yang akan digunakan bagi mencapai objektif ialah menggunakan kaedah kualitatif dengan mengaplikasikan kaedah analisis kandungan karya-karya beliau yang merupakan data primer di dalam kajian ini, dan analisis data dilakukan secara deskriptif. Hasil kajian mendapati bahawa Sheikh Abdul Qadir al-Mandili mempunyai ketokohan dalam bidang hadis, bahkan beliau turut menyumbang kepada khazanah hadis Nusantara berdasarkan peninggalan karya hadis beliau

Effects of NaCl salinity on leaf water status, proline and mineral ion content of four Cucurbitaceae species

Members of Cucurbitaceae are salt-sensitive plants and continuous fertilization without sufficient leaching may create saline environment that consequently reduce their growth and yield. A study was carried out to evaluate the physiological responses of four selected Cucurbitaceae species to NaCl salinity stress. Four types of Cucurbitaceae viz. cucumber (Cucumis sativa), squash (Cucurbita moschata), bitter gourd (Momordica charantia) and bottle gourd (Lagenaria siceraria) were subjected to four levels of NaCl (0, 25, 50, 75 mM) and data on leaf relative water content, proline content and concentration of Na+ and Cl- for leaf, stem and root were collected. Given that the dominant salt in saline soils is NaCl, both Na+ and Cl- ions will occur naturally in high concentrations. However, degree of increment was different between species. As salinity levels increased from 0 to 75 mM, Na+ concentrations in roots in bitter gourd had the highest increase; while in leaf had the lowest increase compared to other species. Increment of Cl- in leaf, stem and roots was the lowest in bitter gourd and highest in cucumber. Increase of proline content in cucumber was 3.55 times higher compared to control whereas in squash, bottle gourd and bitter gourd, the increase were respectively 2.00, 1.47 and 2.03 higher compared to their respective control. Proline content in cucumber was negatively correlated with relative water content, RWC (r = - 0.83, p ≤ 0.01), whereas in other species no correlation was recorded. In conclusion, based on Na and Cl ion concentration, RWC and proline content, bitter gourd was least salt-sensitive while cucumber was most salt-sensitive Cucurbitaceae species

Growth, ion contents and photosynthesis of salt-sensitive and less salt-sensitive cucurbits treated with silicon

A study was carried out to evaluate the role of silicon in alleviating NaCl salinity effects on both salt-sensitive (cucumber) and less salt-sensitive (bitter gourd) cucurbit. The species were subjected to two levels of NaCl (0, 50 mM) and three silicon concentrations (0, 50, 100 mg L-1 sodium silicate) and data on growth, Na and Cl concentration of leaves, net photosynthesis (Pn) and stomatal conductance (g s) were collected. When treated with 100 mg L-1 silicon, growth of salt-stressed and non-salt stressed plants for both species was significantly improved, with more beneficial effects recorded on the salt-stressed plants and salt-sensitive species. Plants treated with 50 mg L-1 silicon had 11.11% significantly lower Na + ion in leaf compared to 0 mg L-1 silicon, regardless of species and salinity condition. Treatment of silicon at 100 mg L-1 also significantly increased net photosynthesis and stomatal conductance by 12.13 and 30.14%, respectively. However, no significant beneficial effect of silicon in reducing Cl concentration was recorded. In conclusion, application of silicon can alleviate salinity stress in both salt-sensitive species (cucumber) and less salt-sensitive species (bitter gourd) by reducing sodium toxicity and increasing photosynthetic activity which evident in improvement of growth parameters

Preliminary analysis of eddy current and iron loss in magnetic gear in electric vehicle

The inclusion of a high energy density permanent magnet into magnetic gear improves the machine's torque density. However, it also contributes to eddy current loss, especially in a high-speed application such in electric vehicle. In this paper, the losses from eddy current and iron loss are investigated on concentric magnetic gear (CMG). Torque multiplier CMG is designed with 8/3 gear ratio for this study. Iron loss and eddy current loss are compared and discussed. Based on this study, eddy current loss contributes to almost 96% of the total loss. This finding is hoped to direct the researcher to focus more on reducing loss associated with eddy current loss

Preliminary Study On Yoke Sizing Of Concentric Magnetic Gear

In this paper, torque, torque density, efficiency and efficiency slope of concentric magnetic gear (CMG) at different yoke sizes are evaluated using 2D finite element. Transient analysis when eddy current loss included and excluded are simulated. Efficiency to speed o used in this study is similar to the original gear ratio, 5.5. The change in the yoke size also effect the torque density of the CMG. The finding showed that the change in size at the outer rotor yoke influence the torque and efficiency the most. The smallest outer rotor yoke yields higher torque density of 55% then the average value in this study and slower gear efficiency degradatio

Electromagnetic torque performance evaluation of concentric magnetic gear alternative conditions using finite element

Concentric magnetic gear (CMG) research mainly focuses on the CMG act as torque increaser and with stationary pole piece condition. Yet, technically CMG can be designed as speed increaser gear with the alternative rotating condition. This paper investigates an initial torque performance of CMG in alternative conditions operating as torque increaser and speed increaser gear. The conditions are when either the inner pole pair or outer pole pair is set stationary while the pole piece component act as rotors. The structure and working principle of the motor are described in detail. The torque performance from finite element software, JMAG Designer 16.0 simulation, as compared with the conventional condition and discussed briefly. The result showed that the conventional condition generates a minor percentage of torque ripple at 1.52%. The highest gear ratio is achieved when the pole piece serves as the outer rotor. Abnormality was also discovered in the conventional condition when the gear operates as a speed increaser. This study concludes that the CMG functions better as a torque increaser instead of a speed increaser gear