21 research outputs found

    Gravitational aeration tower filter system to increase the dissolved oxygen amount for iron removal in groundwater

    Get PDF
    This paper discusses the Gravitational Aeration Tower Filter System (GATS) aims to increase the amount of Dissolved Oxygen (DO) for iron removal in groundwater. The groundwater is mainly used in remote areas. The presence of a large volume of iron contained in the groundwater will subject to water contamination besides limiting the lifespan of existing water filter to filter the contaminants. Pre-treatment systems i.e., aeration techniques are often used to reduce the amount of iron contained in the groundwater. One of the aeration techniques i.e., the GATS is proposed and designed for this work. The GATS is tested to assess its effectiveness in increasing the DO and in the removal of iron in the water. The study area is located in Kampung Majid Ibrahim, Simpang Renggam. The initial value of the iron in the tubewell ranged from 1.4 mg/L to 2.3 mg/L, which exceeded the standard limit of 0.3 mg/L. Using AQUAREAD AP2000 and Hanna High Iron Checker, data collection is carried out in-situ testing. The flow rate is set at 5.5 L/min through the GATS, with varying air parameters. The results of the GATS test demonstrate the DO percentage increases up to 90.50 % and the percentage of iron removal is up to 10.24% with an airflow of 1.0 L/min

    Fabrication and characterization of crystalline cupric oxide (CUO) films by simple immersion technique

    Get PDF
    Cupric oxide (CuO) is one of the most promising p-type semiconducting materials used in p-n junction solar cells. Most of the researchers use electrochemical deposition (ECD) to deposit CuO film. However, it always requires a conductive substrate and the resulting film is porous. In this work, we demonstrated a simple method using an immersion technique to deposit nanostructured CuO for p-n solar cell application. Compared to ECD which end up with only pyramid-like structure, an immersion technique offers flexibility on the CuO nanostructures such as spheres, particles, diamond etc. This technique also offers higher deposition rate which allow deposition at thicker thickness. The adherence to the substrate can be manipulated depending on the pH of the solution. The resuling film was tested into a p-n solar cell using configuration of Au/ZnO/Cuo/ITO/glass. Although there is no efficiency obtained under the solar radiation, it shows a solar cell characteristic with open circuit voltage (Voc) of 1.5

    Gravitational Aeration Tower Filter System to Increase the Dissolved Oxygen Amount for Iron Removal in Groundwater

    Get PDF
    This paper discusses the Gravitational Aeration Tower Filter System (GATS) aims to increase the amount of Dissolved Oxygen (DO) for iron removal in groundwater. The groundwater is mostly used in remote areas. The presence of a large volume of iron contained in the groundwater will subject to water contamination besides limiting the lifespan of existing water to filter the contaminants. Pre-treatment systems i.e., aeration technique is often used to lower the amount of iron ​​contained in the groundwater. One of the proposed aeration techniques i.e., the GATS has been designed in this work. The GATS is tested to observe its effectiveness to increase the DO and iron removal in the water. The area of study is conducted in Kampung Majid Ibrahim, Simpang Renggam. The initial value of the iron in the tubewell is between 1.4 mg/l to 2.3 mg/l, which has exceeded the limit standard of 0.3 mg/l. Data collection is carried out in-situ testing using AQUAREAD AP2000 and Hanna High Iron Checker. The flow rate through the GATS is fixed to 5.5 L/min, with air parameters are varied. The results of the GATS test demonstrate the DO percentage increases up to 90.50 % and the percentage of iron removal is up to 10.24% with the airflow of 1.0 L/min

    Decision making process model for housing developers in Malaysia

    Get PDF
    Housing development involves myriads of interrelated processes which include series of decision making functions. Decision making is a multi-level process that influences the success of a proposed housing project. A housing project may fail or suffer some of serious setback if the decision making function is flawed or has been made on an ad hoc basis or based on unreliable, imperfect or hazy information. Decisions have to be made empirically using scientific methods and tools based on accurate and reliable data and information in today’s business environment. The main aim of this study is to develop a process model for investment decision making in housing development at the strategic phase of the project that is, initiation and feasibility stages in Malaysia. The objectives of this study are three pronged – one, to identify the decision making practiced among Malaysian housing developers, two to identify the methods and tools used by them to make decisions and three to determine the types of information required for making decisions. This research involved the development of theoretical model by synthesising the models developed by a number of prominent authors and researchers on the subject of decision making. It also uses the Delphi method to collect and analyse the appropriate data and information. For a start of the study, 50 numbers of developers were selected as samples. But only 34 responded to the second stage of the information gathering process. At the final stage of the study only 12 developers or participants were left for the final process of the study. The data was analysed using the descriptive statistical techniques. This study affirms that Malaysian developers tend to make their investment decisions based on simple interpolation of historical data and using simple statistical or mathematical techniques in deciding the investment. This study suggested that the Malaysian housing developers skipped several important decision making functions. These shortcomings were mainly due to time and financial constraints and the lack of statistical or mathematical expertise among the professionals and managers in the organisations. The findings allowed a critical review of the theoretical model which followed by the development of a revised process model of decision making for housing development at strategic phase i.e. at the initial and feasibility stages

    Influence of oxygen flow rate on the characteristics of the Tungsten Oxide using RF Magnetron Sputtering

    No full text
    Abstract-Tungsten Oxide (WO3) thin films were deposited using 99.9% pure tungsten target onto ITO substrate using RF magnetron sputtering in the range oxygen flow rates of 30-50%. The influence of the oxygen flow rate on characteristic of WO3 thin films has been investigated. The transmittance, resistivity, crystallite, roughness, and surface morphology were measured by UVVis, 2-point probe, X-Ray Diffraction (XRD), Atomic Force Microscopy (AFM), and Field Emission Scanning Electron Microscopy (FE-SEM) respectively. Experimental result showed that the deposition rate of WO3 thin films decreased by increasing oxygen flow rate. A poor crystalinity or more too amorphous of WO3 thin films produces by using various oxygen content. A higher optical transmittance spectrum detected at 30% oxygen content about 86% at wavelength 550nm. I. INTRODUCTION WO3 have been studied due to their characteristic on optical transmittance since 1980s with the realization WO3 acting as electrochromic materials. The most promising WO3 widely used in smart glass, gas sensor, automotive rear-view mirrors, and sun roof

    Influence of oxygen flow rate on the characteristics of the Tungsten Oxide using RF Magnetron Sputtering

    No full text
    Abstract-Tungsten Oxide (WO3) thin films were deposited using 99.9% pure tungsten target onto ITO substrate using RF magnetron sputtering in the range oxygen flow rates of 30-50%. The influence of the oxygen flow rate on characteristic of WO3 thin films has been investigated. The transmittance, resistivity, crystallite, roughness, and surface morphology were measured by UVVis, 2-point probe, X-Ray Diffraction (XRD), Atomic Force Microscopy (AFM), and Field Emission Scanning Electron Microscopy (FE-SEM) respectively. Experimental result showed that the deposition rate of WO3 thin films decreased by increasing oxygen flow rate. A poor crystalinity or more too amorphous of WO3 thin films produces by using various oxygen content. A higher optical transmittance spectrum detected at 30% oxygen content about 86% at wavelength 550nm. I. INTRODUCTION WO3 have been studied due to their characteristic on optical transmittance since 1980s with the realization WO3 acting as electrochromic materials. The most promising WO3 widely used in smart glass, gas sensor, automotive rear-view mirrors, and sun roof

    The effects of gas flow rate and annealing on the morphological properties of zinc oxide nanostructures thin film using chemical vapour deposition process

    No full text
    Zinc Oxide nanostructures thin films have been deposited on glass substrates by using chemical vapour deposition technique at 1000°C assisted by gas blocker. Glass substrates was sputtered by ~5nm of gold to form a catalyst layer on top of glass. Different gas flow rates of 0.05, 0.10, 0.20, 0.40 L/min were used in the deposition. After the deposition, the layer was annealed at temperatures of 500°C for 1 hours under atmospheric pressure. The surface morphologies of ZnO thin film were investigated field emission scanning electron microscope (FESEM). X-ray diffraction (XRD) results confirm the presence of ZnO layer with high peak of (002) crystal orientation and shows improvement after annealing. The mechanism of ZnO nanostructures formation will be discussed in this paper

    Sonicated Sol-gel Preparation of Nanoparticulate ZnO Thin Films with Various Deposition Speeds: The highly Preferred c-axis (0 0 2) Orientation Enhances the Final Properties

    Get PDF
    Zinc oxide (ZnO) thin films have been deposited onto glass substrates at various deposition speeds by a sonicated sol-gel dip-coating technique. This work studies the effects of deposition speed on the crystallisation behaviour and optical and electrical properties of the resulting films. X-ray diffraction (XRD) analysis showed that thin films were preferentially oriented along the (0 0 2) c-axis direction of the crystal. The transformation sequence of strain and stress effects in ZnO thin films has also been studied. The films deposited at a low deposition speed exhibited a large compressive stress of 0.78 GPa, which decreased to 0.43 GPa as the deposition speed increased to 40 mm/min. Interestingly, the enhancement in the crystallinity of these films led to a significant reduction in compressive stress. All films exhibited an average transmittance of greater than 90% in the visible region, with absorption edges at ∼380 nm. The photoluminescence (PL) measurements indicated that the intensity of the emission peaks varied significantly with deposition speed. The optical band gap energy (Eg) was evaluated as 3.276–3.289 eV, which increased with decreasing compressive stress along the c-axis. The energy band gap of the resulting ZnO films was found to be strongly influenced by the preferred c-axis (0 0 2) orientation
    corecore