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Search Results: 1 - 10 of 4080 matches for " Noor Asmawati MOHD ZABIDI "
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Effect of Loading on the Physicochemical Properties of Alumina Supported Co/Mo Bimetallic Nanocatalysts
Sardar Ali,Noor Asmawati Mohd Zabidi,Duvvuri Subbarao
Journal of Applied Sciences , 2011,
Abstract: The present research deals with the synthesis of cobalt bimetallic Co/Mo nanocatalysts supported on alumina. The nanocatalysts were prepared by wet impregnation method. The samples were characterized in terms of reducibility, dispersion and particle size using Temperature Programmed Reduction (TPR), Transmission Electron Microscopy (TEM) and BET-surface area analysis. H2-TPR analysis of Co/Al2O3 indicated three temperature regions at 380C (low temperature), 680C (medium temperature) and 900C (high temperature). The incorporation of molybdenum into cobalt nanocatalysts shifted the reduction temperatures towards higher temperature but the percentage of species being reduced at low temperature increased also incorporation of molybdenum reduce the crystallinity but decreased the metal particle size of the catalysts. Increasing metal loading from 5 to 10 %wt increased the reducibility of bimetallic nanocatalysts.
Synthesis and Characterization of Silica-Supported Cobalt Nanocatalysts Using Strong Electrostatic Adsorption
Chee Kai Ling,Noor Asmawati Mohd. Zabidi,Chandra Mohan
Journal of Applied Sciences , 2011,
Abstract: Strong Eelectrostatic Adsorption (SEA), a simple yet logical method, was employed to synthesize cobalt catalysts supported on silica. Mono-dispersed non-porous silica sphere was synthesized as a model support using modified Stber method. Point of zero charge (PZC) of silica synthesized in-house was determined using equilibrium pH at high oxide loading (EpHL) method. Cobalt uptake versus pH was studied to determine the optimum pH. High cobalt uptake at basic pH and low cobalt uptake at acidic pH indicates electrostatic interaction between the cobalt complexes in the precursor solution and the hydroxyl group on the supports surface. Catalysts prepared at optimum pH were characterized using TPR, XPS and TEM. TPR shows reduction peak at high temperature (587C) indicating strong interaction between cobalt and silica support. XPS shows presence of Co2+ species on the surface, but no cobalt-ammine complex was detected. TEM images show fairly well dispersed cobalt particles on the support. SEA was deemed a suitable method to prepare supported cobalt catalysts.
Effect of niobium promoter on iron-based catalyst for Fischer-Tropsch reaction
Sardar ALI,Noor Asmawati MOHD ZABIDI,Duvvuri SUBBARAO,
Sardar ALI
,Noor Asmawati MOHD ZABIDI,Duvvuri SUBBARAO

燃料化学学报 , 2012,
Abstract: Niobium-promoted Fe/CNTs catalysts were prepared using a wet impregnation method.Samples were characterized by nitrogen adsorption,H2-TPR,TPD,XRD and TEM.The Fischer-Tropsch Synthesis(FTS) was carried out in a fixed-bed microreactor at 220 ℃,1 atm and H2/CO=2 for 5 h.Addition of niobium into Fe/CNTs increased the dispersion,decreased the average size of iron oxide nanoparticles and the catalyst reducibility.Niobium-promoted Fe catalyst resulted in appreciable increase in the selectivity of C5+ hydrocarbons and suppressed methane formation.These effects were more pronounced for the 0.04%Nb/Fe/CNTs catalyst,compared to those observed from other niobium compositions.The 0.04%Nb/Fe/CNTs catalyst enhanced the C5+ hydrocarbons selectivity by a factor of 67.5% and reduced the methane selectivity by a factor of 59.2%.
Synthesis and Characterization of Silica-supported Iron Nanocatalyst by Modified Colloidal Method
Nor Aziyan Mohd Nasir,Noor Asmawati Mohd Zabidi,Chong Fai Kait
Journal of Applied Sciences , 2011,
Abstract: Silica-supported iron nanocatalysts for Fischer-Tropsch Synthesis (FTS) were prepared using the modified colloidal method in the presence of surfactants in an organic medium. The iron loading on silica support was varied at 3, 5 and 6 wt.%. The samples were characterized by XPS, TPR and TEM. The presence of Fe2O3 on the silica support was confirmed by XPS. TPR analysis showed that the increase in Fe loading caused the first reduction temperature of the nanocatalysts to shift to a higher temperature. TEM analysis revealed that the iron nanoparticles were not uniformly distributed on the silica support. The size of iron nanoparticles ranged from 4 to 20 nm. For the 3 and 5 wt.% Fe/SiO2, the size of the iron nanoparticles were mostly in the range of 1-5 nm, whereas for the 6 wt%, most of the iron nanoparticles (74%) were in the range of 6-10 nm.
Correlation between Fischer-Tropsch catalytic activity and composition of catalysts
Sardar Ali, Noor Mohd Zabidi, Duvvuri Subbarao
Chemistry Central Journal , 2011, DOI: 10.1186/1752-153x-5-68
Abstract: H2-TPR analysis of cobalt catalyst indicated three temperature regions at 506°C (low), 650°C (medium) and 731°C (high). The incorporation of iron up to 30% into cobalt catalysts increased the reduction, CO chemisorption and number of cobalt active sites of the catalyst while an opposite trend was observed for the iron-riched bimetallic catalysts. The CO conversion was 6.3% and 4.6%, over the monometallic cobalt and iron catalysts, respectively. Bimetallic catalysts enhanced the CO conversion. Amongst the catalysts studied, bimetallic catalyst with the composition of 70Co30Fe showed the highest CO conversion (8.1%) while exhibiting the same product selectivity as that of monometallic Co catalyst. Monometallic iron catalyst showed the lowest selectivity for C5+ hydrocarbons (1.6%).Fischer-Tropsch synthesis (FTS) is a process which deals with the conversion of syngas derived from coal, biomass and natural gas into hydrocarbons consisting of paraffins, olefins, alcohols and aldehydes with a high cetane number and is environmentally friendly [1]. Due to limited petroleum reserves and environmental restrictions, Fischer-Tropsch synthesis (FTS) is gaining more attention nowadays than ever. FTS is considered as a surface-catalyzed polymerization reaction. During this process, CO is adsorbed on the surface of the transition metal and hydrogenated producing CHx monomers which consequently propagate to produce hydrocarbons and oxygenates with a broad range of functionalities and chain lengths [2].All the group VIII elements show considerable activity for this process. Among them Co, Fe and Ru present the highest activity [3]. Due to high activity for Fischer-Tropsch synthesis, high selectivity to linear products, more stability towards deactivation, low activity towards water-gas shift (WGS) reaction and low cost compared to Ru, cobalt-based catalysts are the preferred catalyst for Fischer-Tropsch synthesis [4,5]. In order to enhance the catalytic activity and stability, diffe
TRUST AND COMMITMENT: DO THEY INFLUENCE E-CUSTOMER RELATIONSHIP PERFORMANCE?
Nor Azila Mohd Noor
International Journal of Electronic Commerce Studies , 2012,
Abstract: Customer relationship management can help companies build lasting relationships with their customers. Today, CRM has dramatically changed because the internet can be used for CRM applications. Thus, Electronic Customer relationship management (e-CRM) is a comprehensive business and marketing strategy that integrates people, processes, technology and all business activities for attracting and retaining customers through the internet and mobile phones. E-CRM results in repeat purchases, word of mouth, retention, cross buying, brand loyalty and customer satisfaction. The keen competition in the communication and mobile phone service market place and the increasing numbers of mobile phone users worldwide has influenced researchers to investigate factors that contribute to e-CRM performance. This study investigates the influence of customer trust and commitment on e-CRM performance in the Jordanian mobile phone services industry. The analysis shows that customer trust and commitment were positively related to e-CRM performance.
Distributed Java Mobile Information System
Ahmad Shukri Mohd Noor
Communications of the IBIMA , 2009,
Abstract: Technology is now everywhere; integrated into our everyday objects and activities. Mobile computers and devices are now widely affordable and powerful enough. Because of that, developments of mobile applications become a phenomenon today. Mobile applications could be used both to connect people with each other, and to link them with crucial data from almost anywhere in mobile manner. Since mobile devices come in a variety of purposes and properties and in different communication mechanisms, a portable software platform and a flexible and extensible networking supports need to be considered. Java, specifically Java Micro Edition (JME), is particularly an attractive development environment that suits the purpose. This paper discusses a research project of a Java-based smart mobile application. The application, a client/server based application, is designed using JME. It allows the built application to be deployed on any client devices and access to a large variety of network services on the server side. The open source database.
Foreign Language Vocabulary Learning Strategies in Malaysia  [PDF]
Zaid Arafat Mohd Noor, Nik Mohd Rahimi Nik Yusoff, Irma Martiny Md. Yasim, Mohd Yusri Kamarudin
Creative Education (CE) , 2016, DOI: 10.4236/ce.2016.73042
Abstract: Arabic Language is a compulsory subject for students in National Religious Secondary School (SMKA) in Malaysia. Therefore, students need to increase Arabic vocabulary to master their language skills. This study aims to identify the level of Arabic Vocabulary Learning Strategies applied by students and to identify the level of the Arabic Vocabulary Mastery by students of National Religious Secondary School (SMKA). The study used questionnaire and a written test as an instrument of data collection. The sample of study consisted of 157 Form Four students randomly chosen from Secondary School in Malaysia. The results showed that the level of Arabic Vocabulary Learning Strategies applied by students and the level of the Arabic Vocabulary Mastery by students at Secondary School in Malaysia were at moderate level. Pedagogical implications of this study is that effective Vocabulary Learning Strategies should be exposed to the students in the learning process, so that students can use various Vocabulary Learning Strategies to enhance their Arabic Vocabulary Mastery.
Mechanical and superconducting properties of nanosize MgO added dip-coated Bi2Sr2CaCu2O8 superconducting tape  [PDF]
Nasri A Hamid, Mohd Yusri Abd Rahman, Noor Fairuz Shamsudin
Natural Science (NS) , 2011, DOI: 10.4236/ns.2011.36067
Abstract: In this work, 3% to 8% (in weight) of nanosize MgO particles was added to Bi2Sr2CaCu2O8 (Bi- 2212) high-temperature superconductor to fab-ricate Bi-2212 superconducting material with superior mechanical properties. The mechanical strength of the samples was studied by con-ducting the compression test at room tempera-ture, and the addition of 5% nanosize MgO par-ticles produced the highest strength when com- pared with other samples. The sample with 5% MgO addition also exhibited superior super-conducting properties. The Bi-2212 powder with 5% nanosize MgO addition was used to fabricate Bi-2212 tapes through the dip-coating-then- stacking method. The fully processed tapes were investigated via dc electrical resistance measurements, XRD patterns, SEM micrographs, transport critical current density and tensile tests. The tensile tests were conducted at room and cryogenic (77 K) temperatures. Results of tensile tests and Young’s modulus for the tapes showed that the Bi-2212 tapes with nanosize MgO addition recorded better mechanical prop-erty compared to the non-added samples both at room and cryogenic temperatures. The double- core tape with 5% MgO addition recorded the highest failure point at 160 MPa. In addition to the strengthening effect that was observed in the nanosize MgO added Bi-2212 superconduc-tor tapes, the superconducting properties re-mained intact in the tapes.
Breast Density: Does It Vary among the Main Ethnic Groups in Malaysia?  [PDF]
Kanaga Kumari Chelliah, Noor Shatirah Mohd Fandi Voon, Hanizan Ahamad
Open Journal of Medical Imaging (OJMI) , 2013, DOI: 10.4236/ojmi.2013.34017
Abstract:

Breast cancer is one of the common cancers among Malaysians and there are associated risk factors which include breast density. Therefore, this study was done to determine the association of breast cancer risks among ethnic groups in relation to breast density. Mammography was done on 300 women with equal numbers of Malays, Chinese and Indians with a mean age of 53.35 ± 7.4 years. Mammograms were evaluated using BI-RADS (Breast Imaging Reporting and Data System) protocol by two independent radiologists for breast density categorization. Chi-square analysis showed an association between breast density and age factor (p < 0.05) whereas body mass index (BMI) was inversely associated with breast density (p > 0.05). There was significant difference in number of children and menopausal status (p < 0.05). Results showed that 65% of Chinese subjects had denser breast density composition as to 50% in Malays and 35% in Indians. There was significant difference between breast density of three ethnic groups (p < 0.05) with Chinese having 2.4 times denser breast (OR = 2.45, 95% CI: 1.466 - 3.948) followed by Malays (OR = 1.020, 95% CI: 0.681 - 1.689) and lowest in Indians (OR = 0.406, 95% CI: 0.247 - 0.668). Based on breast density, the Chinese are at a higher risk of developing breast cancer followed by Malays and lastly Indians.

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