This work deals with preparation of zeolite 5A from Dewekhala kaolin clay in Al-Anbar region for drying and desulphurization of liquefied petroleum gas. The preparation of zeolite 5A includes treating kaolin clay with dilute hydrochloric acid 1N, treating metakaolin with NaOH solution to prepare 4A zeolite, ion exchange, and formation. For preparation of zeolite 4A, metakaolin treated at different temperatures (40, 60, 80, 90, and 100 °C) with different concentrations of sodium hydroxide solution (1, 2, 3, and 4 N) for 2 hours. The zeolite samples give the best relative crystallinity of zeolite prepared at 80 °C with NaOH concentration 3N (199%), and at 90 and 100°C with NaOH concentration solution 2N (184% and 189%, respectively). Zeolite 5A was prepared by ion exchange of zeolite 4A prepared at 90°C and 2N NaOH concentration with 1.5 N calcium chloride solution at 90 °C and 5 hours, the ion exchange percentage was 66.6%. The formation experiments included mixing the prepared powder of 5A zeolite with different percentages of kaolin clay, citric acid and tartaric acid to form an irregular shape of zeolite granules. Tartaric acid binder gives higher bulk crushing strength than that obtained by using citric acid binder with no significant difference in the surface area. 7.5 weight% tartaric acid binder has the higher bulk crushing strength 206 newton with surface area 267.4 m2/g. Kaolin clay binder with 15 weight% gives the highest surface area 356 m2/g with bulk crushing strength 123 newton, it was chose as the best binder for zeolite 5A. The prepared granules of 5A zeolite were used for the adsorption experiments of H2O, and H2S contaminants from LPG. Different flow rates of LPG (3, 4, and 5 liter/minute) were studied. It was found that H2O is the strongly adsorbed component and H2S is the weakly adsorbed component. The best flow rate in this work for H2O, and H2S adsorption is 5 liter/minute of LPG. The adsorption capacity for H2O was 7.547 g/g and for H2S was 1.734 g/g.
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We propose two simple, rapid, and convenient spectrophotometric methods which are described for the determination of cephalexin in bulk and its pharmaceutical preparations. They are based on the measurement of the flame atomic emission of potassium ion (in the first method) and colorimetric determination of the green colored solution at 610 nm formed after the reaction of cephalexin with potassium permanganate as an oxidant agent (in the second method) in basic medium. The working conditions of the methods are investigated and optimized. Beer's law plot shows a good correlation in the concentration range of 5-40?g ml-1. The detection limits are 2.573,2.814 ?g ml-1 for the flame emission photometric method and 1.844,2.016 ?g ml-1 for colo
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In this work, composite materials were prepared by mixing different concentrations of ferrites with polyacrylonitrile (PAN) polymer. Using the electrospinning technique, these composites were deposited on a p-type silicon wafer. The prepared samples demonstrated nanofibers in both pure PAN polymers and their composites with ferrite. Prior to examining the humidity sensing effectiveness with a percentage of relative humidity at a frequency of 10 kHz, based on ambient temperature and a relative humidity range of 50–100%, the composite nanofibers demonstrated stronger humidity sensing compared to the pure PAN nanofibers, which demonstrated a powerful resistance response. More precisely, the PAN@ferrite nanocomposite showed a broad adsorption
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The presented work shows a preliminary analytic method for estimation of load and pressure distributions on low speed wings with flow separation and wake rollup phenomena’s. A higher order vortex panel method is coupled with the numerical lifting line theory by means of iterative procedure including models of separation and wake rollup. The computer programs are written in FORTRAN which are stable and efficient.
The capability of the present method is investigated through a number of test cases with different types of wing sections (NACA 0012 and GA(W)-1) for different aspect ratios and angles of attack, the results include the lift and drag curves, lift and pressure distributions along the wing s
... Show MoreIntroduction: Carrier-based gutta-percha is an effective method of root canal obturation creating a 3-dimensional filling; however, retrieval of the plastic carrier is relatively difficult, particularly with smaller sizes. The purpose of this study was to develop composite carriers consisting of polyethylene (PE), hydroxyapatite (HA), and strontium oxide (SrO) for carrier-based root canal obturation. Methods: Composite fibers of HA, PE, and SrO were fabricated in the shape of a carrier for delivering gutta-percha (GP) using a melt-extrusion process. The fibers were characterized using infrared spectroscopy and the thermal properties determined using differential scanning calorimetry. The elastic modulus and tensile strength tests were dete
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<p>The demand for internet applications has increased rapidly. Providing quality of service (QoS) requirements for varied internet application is a challenging task. One important factor that is significantly affected on the QoS service is the transport layer. The transport layer provides end-to-end data transmission across a network. Currently, the most common transport protocols used by internet application are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol). Also, there are recent transport protocols such as DCCP (data congestion control protocol), SCTP (stream congestion transmission protocol), and TFRC (TCP-friendly rate control), which are in the standardization process of Internet Engineering Task
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Objective(s): This study aims to assess health related quality of life among Iraqi patients with chronic viral hepatitis
B and C also to find out the relationship between health related quality of life and patients demographic
characteristic and to design a new measurement scale for assessing QoL among viral hepatitis B and C patients
which can be suitable to be adopted for Iraqi patients
Methodology: A descriptive quantitative study is carried out at Gastroenterology and Hepatology Teaching
Hospital from February, 1st, 2011 to August 30th 2011, Anon probability (purposive sample) of (100) chronic viral
hepatitis B and C persons , who were clients of Gastroenterology and Hepatology Teaching Hospital / outpatient
clin