248 research outputs found

    Characterization of LUSI Mud as Geopolymer Raw Material

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    The mud of mud volcano samples were collected from an eruption site named ‘LUSI’ (Lumpur “mud” –Sidoarjo), East Java, Indonesia for characterization. Analysis showed that, the major constituents of mud are SiO2 and Al2O3 which are higher than those in fly ash. The particle of mud has a flake-shaped particle and the overall particle size is dominated by particles between 2.5μm – 25.0μm. The results of XRD shows that mud of mud volcano have a characteristic of structurally disordered compounds, and a set of peaks corresponding to minor crystalline phases such as quartz, feldspars, and kaolinite. FTIR adsorption bands of the raw material of mud have the chemical bonding between bands 1-5

    Solderability of Sn-0.7Cu/Si3N4 lead-free composite solder on Cu-substrate

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    AbstractReinforcing high performance ceramic particulates is an effective approach to improve solderability of lead-free Sn-0.7Cu solder. Various weight percentage compositions (0.5, 1.0, and 1.5) of Silicon Nitride (Si3N4) reinforced in Sn-0.7Cu solder were developed using powder metallurgy (PM) routes to investigate their solderability properties on copper (Cu) substrate. The solderability performances of the new composite solder will be determined and analyzed based on their contact angles on Cu substrate, including interface intermetallic compound (IMC) layer thickness and IMC phases formed for different Si3N4 ratios. Results also show an improvement in solderability of the Sn-0.7Cu/Si3N4 composite lead-free solder with optimum wettability achieved by 1.0wt.% Si3N4. The minimal average decrease in IMC layer thickness and the formation of the different shaped of scallops figuring the IMC layer were observed. X-ray diffraction (XRD) also revealed the decreasing peak intensity of Cu6Sn5 phases with Si3N4. Overall, the entire range of composition of Si3N4 into Sn-0.7Cu monolithic solder use in this study indicated an enhancement of solderability performances on Cu-substrates

    Glomerulogenesis and Histomorphometeric in Mus musculus Embryo

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    In mammals, the kidneys originate in an embryo from the mesoderm through three excretory organs, namely: Pronephros, Mesonephros, and Metanephros. After the formation of Metanephros is completed, the kidneys begin to form nephrogenesis through mesenchymal cells located at the tip of the ureteric bud, that contribute in the formation of glomerulus and Renal tubules. The stages of glomerulus formation in the embryo of albino mice at the age of 14 to 19 days of gestation were studied. It was obtained after the sacrifice of the expectant mother and the kidneys were excised from the embryos and fixed using Aqueous Bouin's solution, Microscopic slices with a thickness of 6 microns were then made in a paraffin method and were photographed by a camera for microscopic imaging. Histological measurements were performed on them using the program IMAGE J program and analyzed statistically using the SPSS program.  Results of the current study showed the presence of five stages of glomerulus formation, namely, the renal vesicle, which represents the first stage in the formation of the nephron and glomerulus. This is followed by the Comma shape stage, S-shaped stage, Capillary loop stage and finally the Mature glomerulus. This is surrounded by a capsule, known as Bowman’s capsule being part of the Malpighian or Renal corpuscle. The statistical analysis showed that there were significant differences between the average diameters of the glomerular development stages, and that the mature glomerulus was larger in diameter than the rest of the stages. The study aims to determine the stages of glomerulus formation and histologically measure its diameter in the embryo of a Mus musculus.

    A novel approach to approximate fractional derivative with uncertain conditions

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    This paper focuses on providing a new scheme to find the fuzzy approximate solution of fractional differential equations (FDEs) under uncertainty. The Caputo-type derivative base on the generalized Hukuhara differentiability is approximated by a linearization formula to reduce the corresponding uncertain FDE to an ODE under fuzzy concept. This new approach may positively affect on the computational cost and easily apply for the other types of uncertain fractional-order differential equation. The performed numerical simulations verify the proficiency of the presented scheme

    Construction Firm Readiness towards Implementing Integrated Project Delivery (IPD)

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    The Malaysian government has taken the initiative of implementing Industrialised Building System (IBS) in which components are manufactured in mass production under a controlled environment (on or off site), transported, positioned and assembled into a structure with minimal additional site works. It is hope that IBS can improve the performance of construction industry. However, one of the main barriers in Malaysian IBS implementation is lack of integration among stakeholder involved during the project delivery stage. In order to overcome this barrier, a new collaborative procurement or project delivery namely as Integrated Project Delivery (IPD) which is using a multi-party contract (more than two parties selected) has been introduced. Integrated Project Delivery (IPD) is defined as a project delivery approach that integrates people, systems, business structures and practices into a process that collaboratively harnesses the talents and insights of all project participants to optimise the results, increase value to the owner, reduce waste, and maximize efficiency through all phases of design, fabrication and construction. Although, many researchers have argue the importance of IPD in project delivery process, but the readiness of construction industries must be established. This research has used a quantitative research process that involved a few phases including literature review stage, data collection stage, framework development stage, validation and recommendation stage. This research is to obtain data based on multidisciplinary IBS stakeholders perspectives, respondent include project managers, resident engineers, architects and contractors are among the potential candidates. Respondents that directly involved in the construction industry mentioned that their firms are willing to change and implement IPD. The firms readiness recorded at the moderate mean value. It can be noted that each firm involved as respondents are ready to implement

    The Effect of Acidic to the Fly Ash Based Geopolymer Artificial Aggregate

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    Abstract: The Ordinary Portland Cement (OPC), which is widely used materials not only consumes significant amount of natural resources and energy but also pollutes the atmosphere by the emission of CO 2 . Hence, reduce this ill effect, the search for alternative result is geopolymer concrete. This experiment research focused on utilizing fly ash as source material. Fly ash is receiving more attention now since their uses generally improve the properties in construction industry, cost saving and reduction of negative environmental affects. Three different molarity of paste has been tested to acidic environment to determine the effect of acidic to the fly ash based geopolymer artificial aggregate. The geopolymer paste samples were cured at 70°C for 1 day and keep in room temperature until the testing days. The compressive strength and acid resistant testing was done at after 28 days. The result showed that the geopolymer paste with NaOH concentration of 12 M produced maximum strength

    Analysis of the Thermal and Magnetic Properties of Amorphous Fe 61Co10Zr2.5Hf2.5Me2W2B20 (Where Me = Mo, Nb, Ni Or Y) Ribbons

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    The paper presents the results of structural and magnetic properties and thermal stability for a group of functional materials based on Fe61Co10Zr2.5Hf2.5Me2W2B20 (where Me = Mo, Nb, Ni or Y). Samples were obtained in the form of ribbons using melt-spinning method. The X-ray diffraction patterns of investigated samples confirmed their amorphous structure. Based on the analysis of DSC curves characteristic temperatures: glass forming temperature (Tg), crystallization temperature (Tx) and temperature range of the supercooled liquid ΔTx were determined. Small addition of transition metals elements has strong influence on magnetic and thermal parameters of studied materials. The comprehensive studies revealed that in terms of magnetic properties the Ni-addition resulted in highest reduction in coercivity and anisotropy field

    Pos Besar, 01000 Kangar, Perlis Malaysia., Development of Pilot Plant for Novel Geopolymer Brick Making Machine

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    With rapid growing country's development and rose in construction activity, rising demand of building materials and increased construction wastes have encouraged the development of new building materials. Geopolymer based construction materials such as concrete, aggregate, brick and so on are getting good response by the public especially those in the construction and development industries nowadays. Geopolymer bricks making process consume less energy and low cost in term of raw materials and production compared to conventional bricks. It become a nessesity nowadays to provide a machine that produced construction material based on geopolymer that are compatible with geopolymer process that can improved productivity and promote geopoymer construction material to repace convertional construction material. This paper presents the main component, specification and controlling system of the geopolymer brick making machine. This paper also describes the basic operation of the brick produced by using novel geopolymer brick making machine. The capacity production is adequate which has mixing tank capacity of 40 kg per batch with high compaction pressure which is 40 tonne and low curing temperature needed (less than 100 °C) that can produce high quality and environmental friendly brick. The size of the brick produced is 9" x 4" x 2.5" accordance with the standard size based on British Standard BS 3921: 1985

    Prevalence and Determinants of Metabolic Syndrome in Qatar: Results from a National Health Survey

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    OBJECTIVES: To determine optimum measurements for abdominal obesity and to assess the prevalence and determinants of metabolic syndrome in Qatar. DESIGN: National health survey. SETTING: Qatar National STEPwise Survey conducted by the Supreme Council of Health during 2012. PARTICIPANTS: 2496 Qatari citizens aged 18-64 representative of the general population. PRIMARY AND SECONDARY OUTCOME MEASURES: Measure of obesity (body mass index, waist circumference or waist-to-height ratio) that best identified the presence of at least 2 other factors of metabolic syndrome; cut-off values of waist circumference; frequency of metabolic syndrome. RESULTS: Waist circumference ≥102 for men and ≥94 cm for women was the best predictor of the presence of other determinants of metabolic syndrome (raised blood pressure, fasting blood glucose, triglycerides and reduced high-density lipoprotein cholesterol). Using these values, we identified 28% of Qataris with metabolic syndrome, which is considerably lower than the estimate of 37% calculated using the International Diabetes Federation (IDF) criteria. Restricting the analysis to participants without known elevated blood pressure, elevated blood sugar or diabetes 16.5% would be classified as having metabolic syndrome. In a multivariable logistic regression analysis, the prevalence of metabolic syndrome increased steadily with age (OR=3.40 (95% CI 2.02 to 5.74), OR=5.66 (3.65 to 8.78), OR=10.2 (5.98 to 17.6) and OR=18.2 (7.01 to 47.5) for those in the age group \u2730-39\u27, \u2740-49\u27, \u2750-59\u27, \u2760-64\u27 vs \u2718-29\u27; p CONCLUSIONS: Waist circumference was the best measure of obesity to combine with other variables to construct a country-specific definition of metabolic syndrome in Qatar. Approximately 28% of adult Qatari citizens satisfy the criteria for metabolic syndrome, which increased significantly with age. Education and physical activity were inversely associated with this syndrome
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