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Search Results: 1 - 10 of 593442 matches for " J. M. Jahim "
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Development of Extraction System by using Thermo-Responsive Polymer for Bovine Serum Albumin Recovery
F.A. Abdul Mutalib,J.M. Jahim
Journal of Applied Sciences , 2009,
Abstract: Thermo-responsive polymers, Dehypon LS54 and Berol 370 were paired randomly with starch derivatives, K4484 dextrin and N-Lite D maltodextrin for develop thermoseparating ATPS. The developed systems are DehyponLS54/K4484, DehyponLS54/N-Lite.D and Berol370/K4484. All systems were tested with partitioning of BSA as model protein. Among the tested systems, DehyponLS54/K4484 was found as most suitable system for BSA recovery. A small electrochemical potential effect was observed in DehyponLS54/K4484 dextrin system in which the change of pH (pH 8 to 6) had slightly influence the partitioning behavior of BSA. At both pH, BSA was observed had high affinity to starch enriched phase and it caused a low yield value of BSA after thermoseparation step. However, recovery of BSA in water phase at pH 6 was higher 40% compared to pH 8. The addition of Na2SO4 has lowered the cloud point of Dehypon LS54.
Synthesis, Characterization and Catalytic Performance of Prepared by Sol-Gel Technique
W. N. R. W. Isahak,M. Ismail,N. M. Nordin,J. M. Jahim,M. A. Yarmo
Journal of Nanotechnology , 2011, DOI: 10.1155/2011/507692
Abstract: The purpose of this work is to study the synthesis, characterization, and catalytic performance of two types of solid heteropoly acid catalysts, namely, silicotungstic acid bulk (STAB) and STA-silica sol-gel (STA-SG) compared with sulfuric acid. From the XPS analyses, there was a significant formation of W-O-Si, W-O-W, and Si-O-Si bonding in STA-SG compared to that in STAB. The main spectra of O1s (90.74%, 531.5?eV) followed by other O1s peak (9.26%, 532.8?eV) were due to the presence of W-O-W and W-O-Si bonds, respectively. The STA-SG catalyst was found to be the more environmentally benign solid acid catalyst for the esterification reaction between oleic acid and glycerol due to its lower toxicity supported by silica via sol-gel technique. In addition, the ease of separation for STA-SG catalyst was attributed to its insoluble state in the product phase. The esterification products were then analysed by FTIR and HPLC. Both the H2SO4 and the STAB gave high conversion of 100% and 98% but at a lower selectivity of GME with 81.6% and 89.9%, respectively. On the contrary, the STA-SG enabled a conversion of 94% but with a significantly higher GME selectivity of 95%, rendering it the more efficient solid acid catalyst. 1. Introduction During the recent years, glycerol has been used as combustion materials around the world. The glycerol usage was expanded into many other high-quality products such as pharmaceutical, foods, and engine lubricant. To date, glycerol modification into glycerol monoester (GME) as lubrication materials that was based on the biosources was not really practised in the industry. The nature of the polar head group and the structure of the hydrocarbon tail of GME gave the strong impact as a friction reducer [1]. The GME is synthesized at present by acid catalyzed esterification of glycerol and fatty acids [2, 3]. Recently, list of studies involving alternative heterogeneous catalytic routes have been reported such as the glycerol esterification with lauric acid (LA) and oleic acid (OA) by using functionalized mesoporous materials [4], zeolitic molecular sieves [5, 6], and solid cationic resins [7, 8] as catalysts. In another work, the beta-zeolite catalyst gave the conversion of fatty acids above 20% at optimum condition of glycerol?:?LA molar ratio of 1?:?1 at 100°C for 24 hours [9]. In this work, the usage and activities of the silicotungstic acid bulk (STAB) and the silicotungstic acid-silica sol-gel (STA-SG) have been studied. The STAB consists of two molecular structures, namely, Keggin and Dawson structures with four protons. The
Synthesis, Characterization and Catalytic Performance of H3 SiW12 O40 /SiO2 Prepared by Sol-Gel Technique
W. N. R. W. Isahak,M. Ismail,N. M. Nordin,J. M. Jahim
Journal of Nanotechnology , 2011, DOI: 10.1155/2011/507692
Applications of the Box-Wilson Design Model for Bio-hydrogen Production using Clostridium saccharoperbutylacetonicum N1-4 (ATCC 13564)
W.M. Alalayah,M.S. Kalil,A.A.H. Kadhum,J. Jahim
Pakistan Journal of Biological Sciences , 2010,
Abstract: Box-Wilson Design (BWD) model was applied to determine the optimum values of influencing parameters in anaerobic fermentation to produce hydrogen using Clostridium saccharoperbutylacetonicum N1-4 (ATCC 13564). The main focus of the study was to find the optimal relationship between the hydrogen yield and three variables including initial substrate concentration, initial medium pH and reaction temperature. Microbial growth kinetic parameters for hydrogen production under anaerobic conditions were determined using the Monod model with incorporation of a substrate inhibition term. The values of μmax (maximum specific growth rate) and Ks (saturation constant) were 0.398 h-1 and 5.509 g L-1, respectively, using glucose as the substrate. The experimental substrate and biomass-concentration profiles were in good agreement with those obtained by the kinetic-model predictions. By varying the conditions of the initial substrate concentration (1-40 g L-1), reaction temperature (25-40°C) and initial medium pH (4-8), the model predicted a maximum hydrogen yield of 3.24 mol H2 (mol glucose)-1. The experimental data collected utilising this design was successfully fitted to a second-order polynomial model. An optimum operating condition of 10 g L-1 initial substrate concentration, 37°C reaction temperature and 6.0±0.2 initial medium pH gave 80% of the predicted maximum yield of hydrogen where as the experimental yield obtained in this study was 77.75% exhibiting a close accuracy between estimated and experimental values. This is the first report to predict bio-hydrogen yield by applying Box-Wilson Design in anaerobic fermentation while optimizing the effects of environmental factors prevailing there by investigating the effects of environmental factors.
Determination of Glucose and Fructose from Glucose Isomerization Process by High performance Liquid Chromatography with UV Detection
N A. Rahman,M. Hasan,M.A. Hussain,J Jahim
Modern Applied Science , 2009, DOI: 10.5539/mas.v2n4p151
Abstract: Analysis of fructose and glucose from glucose isomerization process using immobilised glucose isomerase (IGI), {Sweetzyme from Novozymes} are often performed by HPLC methods with refractive index (RI) detector. This study is focused on developing new methods of measuring glucose and fructose using a specific carbohydrate column. The importance of this research, primarily based on the performance of the HPLC with ultra-violet (UV) detection as another alternative of detector rather than using RI . The method was carried out under the following condition; UV detection was made at 195 nm with column temperature of 300C , flow rate of 0.6 ml/min and injections of 20?L . The ratio of acetonitrile and the deionised water used was 80% to 20%. From the results, the detection of fructose and glucose by HPLC with acetonitrile and water as solvents can be obtained using UV detection (195nm) instead of the commonly used detector of RI.
Bio-Hydrogen Production using a Two-Stage Fermentation Process
W.M. Alalayah,M.S. Kalil,A.A.H. Kadhum,J.M. Jahim
Pakistan Journal of Biological Sciences , 2009,
Abstract: A two-stage fermentation process consisting of dark and photo-fermentation periods was carried out in a batch reactor. In the first stage, glucose was fermented in the dark stage using Clostridium saccharoperbutylacetonicum N1-4 (ATCC 13564; CSN1-4) to produce acetate, CO2 and H2. The acetate produced in the first stage is fermented to H2 and CO2 by Rhodobacter sphaeroides NCIMB 8253 for further hydrogen production in the second, illuminated stage. The yield of hydrogen in the first stage was about 3.10 mol H2 (mol glucose)-1 at a glucose concentration of 10 g L-1, pH 6±0.2 and 37°C and the second stage yield was about 1.10-1.25 mol H2 (mol acetic acid)-1 at pH 6.8±0.2 and 32°C, without removal of the Clostridium CSN1-4. The overall yield of hydrogen in the two-stage process, with glucose as the main substrate was higher than single-stage fermentation.
Purification of Crude Glycerol from Transesterification RBD Palm Oil over Homogeneous and Heterogeneous Catalysts for the Biolubricant Preparation
W.N.R.W. Isahak,M. Ismail,M.A. Yarmo,J.M. Jahim
Journal of Applied Sciences , 2010,
Abstract: Crude glycerol samples used in this study consisted of crude glycerol (CG1) produced from homogeneous catalyst (NaOH) obtained from Golden Hope biodiesel plant and crude glycerol (CG2) as a product of heterogeneous catalysed transesterification RBD palm oil using KOH/Al2O3 catalyst. KOH/Al2O3 catalyst was produced by wet impregnation method and characterized by using BET, XRD and SEM-EDX methods. 15% KOH/ Al2O3 has BET surface area of 26.1 m2 g-1 compared with 100.4 m2 g-1 for fresh Al2O3. The first purification stage of the crude glycerol was achieved by employing the neutralization method followed by microfiltration and ion exchange resins methods. Inorganic salts as a result of the neutralization with 85% v/v phosphoric acid were filtered using syringe filter 0.45 μm. Only glycerol peak could be detected using a Dionex C-18 column in the HPLC indicating that the neutralization step enabled the removal of excess homogeneous catalyst as well as the unreacted free fatty acids in the crude glycerol samples. The free ions from salt and catalyst were then eliminated through ion exchange process using Amberlite resins to produce higher glycerol purity. The samples were also analyzed using FTIR to check on their purity level and to detect any impurity that may still exist. The products of this 3-step purification method were deemed comparable to that of a commercial pure glycerol based on the viscosity, pH value, free fatty acid value, moisture content and density rendering them as competitive feedstock for the biolubricant production.
Application of the Aqueous Two-phase Thermoseparating Systems of Dehypon LS 54-the Waxy Maize Starch for Protein Extraction
Ario Betha Juanssil Fero,Jamaliah Md. Jahim
Journal of Applied Sciences , 2010,
Abstract: A thermo-separating aqueous two-phase system composed of Dehypon LS 54, a polymeric surfactant and the waxy maize starch (amylopectin starch), has been used for partitioning of cutinase as a model protein. The phase diagram obtained for this novel polymer-polymer two-phase system shows two-phases with high polymer concentration. The waxy maize starch is enriched in the bottom phase while the copolymer of Ethylene Oxide (EO) and Propylene Oxide (PO) is found in the upper phase. Since, this copolymer (Dehypon LS 54) is the thermo-reactive, the upper phase can be removed and heated above the copolymer’s cloud-point resulting in the formation of a new two-phase system with a lower water phase containing the target protein and an upper copolymer-rich phase. Present results show that the systems were formed by the waxy maize starch and a copolymer Dehypon LS 54 may be considered as an interesting alternative to be used in protein purification due to their low cost, in addition, they offer a viable solution to problems of polymer removal and recycling.
Sodium Hydroxide Pretreatment and Enzymatic Hydrolysis of Oil Palm Mesocarp Fiber
Nur Izzati Iberahim,Jamaliah Md Jahim,Shuhaida Harun,Mohd Tusirin Mohd Nor
International Journal of Chemical Engineering and Applications , 2013, DOI: 10.7763/ijcea.2013.v4.272
Abstract: Sodium hydroxide pretreatment of oil palm mesocarp fiber (OPMF) was carried out with NaOH from 2% to 10% (w/v) at temperature 500C and 700C. The performances of pretreatments were evaluated based on total carbohydrate and reducing sugar including glucose, xylose and arabinose after enzymatic hydrolysis on the pretreated biomass. It was found that the enzymatic hydrolysis had significantly improved when 6% NaOH in 700C applied in the pretreatment process. The highest total reducing sugars produced by means of commercial enzymes was achieved with the overall conversions of glucan and xylan of 87% and 60.73% respectively. The compositions of OPMF in this study are as follows (% g/g dry biomass): glucan, 28.8, xylan, 25.3, arabinan, 1.91, ethanol extractive, 6.32 and ash, 2.60.
Optimization of Electricity Generation and Palm Oil Mill Effluent (POME) Treatment from Microbial Fuel Cell
Swee Su Lim,Jamaliah Md. Jahim,Wan Ramli Wan Daud,Manal Ismail
Journal of Applied Sciences , 2010,
Abstract: Natural micro-flora of Palm Oil Mill Effluent (POME) sludge was grown in dual-chamber Microbial Fuel Cells (MFC) to produce electricity by providing glucose at different concentration. A greater strength of Open Circuit Voltage (OCV) was observed with optimal biomass metabolism activity, as increasing glucose concentrations. The time Response Constant (RC) of OCV was taken everyday to estimate the total time needed to achieve steady state voltage at zero current. The lower value of RC indicates that the strength of OCV value is high and the biomass attached to the anode could be active in producing electrons. At 3 750 mg-COD L-1 with 10% added POME and 10 000 mg-COD L-1 synthetic wastewater, the values of RC for each medium were found as 3.36 and 1.95 h, respectively. The removal efficiency of COD was achieved 72.2% for 10% POME and 89.9% for synthetic wastewater. The initial COD level was found proportionally to the COD removal and maximum power density in the MFC system. However, the results shown that relation between RC value and initial COD level were inversely proportional. The highest power density (with present current density) in POME added and synthetic medium were 3.155 mW m-2 (9.322 mA m-2) and 1.780 mW m-2 (3.996 mA m-2), respectively. The optimal power density that conducted in different level of COD was occurred at day 2 before its start decrease at next consecutive day. The effects of electrochemical parameters to power densities at different initial COD level were also studied using polarization model. From the simulated data, averaged power densities (with present current densities) that could achieved at COD 3750 and 10000 mg L-1 were estimated 2.61 mW m-2 (4.5 and 1.38 mA m-2 (3.5 mA m-2)), respectively. The total losses due to current limitation were eliminated about 15-55 % at high initial COD level based on results mention above. The end of study showed that the maximum power density kept on increased although COD value had reached to the lower level and this could be due to the hydrolysis of inactive of the living cells undergone lysis, has contributed to COD level in the system.
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