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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Analysis of cement and related materials by atomic absorption spectrophotometry using a new fusion system.

January 1995 (has links)
Lam Lik. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 107-112). / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1. --- Chemistry of portland cement manufacture --- p.1 / Chapter 1.2. --- Classical methods of cement analysis --- p.7 / Chapter 1.3. --- Application of instrumental methods in cement analysis --- p.12 / Chapter 1.3.1. --- X - ray fluorescence spectrometry --- p.12 / Chapter 1.3.2. --- Atomic absorption spectrometry --- p.16 / Chapter 1.3.3. --- Other instrumental methods --- p.22 / Chapter 1.4. --- Treatment of data --- p.25 / Chapter 1.5. --- Dissolution techniques for AAS analysis --- p.28 / Chapter 1.5.1 --- Hydrofluoric acid decomposition --- p.28 / Chapter 1.5.2 --- Fusion --- p.30 / Chapter 1.6. --- Research objective --- p.34 / Chapter Chapter 2. --- Analysis of Cement and Raw Meal Samples --- p.35 / Chapter 2.1. --- Experimental --- p.36 / Chapter 2.1.1. --- Reagents --- p.35 / Chapter 2.1.2. --- Instrumental --- p.37 / Chapter 2.1.3. --- Procedure --- p.37 / Chapter 2.1.3.1. --- "Sample solutions for the determination of SiO2, A1203, Fe2O3, Ti02, Na20 and K20" --- p.37 / Chapter 2.1.3.2. --- Sample solutions for the determination of CaO and MgO --- p.38 / Chapter 2.1.3.3. --- "Standard solutions for the determination of SiO2, Al2O3, Fe203, TiO2, Na2O and K2O" --- p.33 / Chapter 2.1.3.4. --- Sample solutions for the determination of CaO and MgO --- p.41 / Chapter 2.1.3.5. --- X-ray briquettes --- p.42 / Chapter 2.2. --- Results and discussion --- p.43 / Chapter 2.2.1. --- The proposed fusion system --- p.43 / Chapter 2.2.2. --- Instrumental conditions --- p.47 / Chapter 2.2.3. --- Accuracy --- p.56 / Chapter 2.2.4. --- Interferences studies --- p.61 / Chapter 2.2.5. --- "Calibration graph, detection limits and precision" --- p.69 / Chapter 2.2.6 --- Real sample analysis --- p.80 / Chapter Chapter 3. --- Analysis of Siliceous Materials and Coal --- p.84 / Chapter 3.1. --- Experimental --- p.84 / Chapter 3.1.1. --- Reagents and instruments used --- p.84 / Chapter 3.1.2. --- Procedure --- p.85 / Chapter 3.1.2.1. --- "Sample solutions for the determination of SiO2, A1203, Fe2O3, Ti02, Na20 and K20" --- p.85 / Chapter 3.1.2.2. --- Sample solutions for the determination of CaO and MgO --- p.85 / Chapter 3.1.2.3. --- "Standard solutions for the determination of Si02, Al2O3, Fe2O3,TiO2, Na20 and K20 in siliceous material and coal" --- p.86 / Chapter 3.1.2.4. --- Standard solutions for the determination of CaO and MgO --- p.87 / Chapter 3.1.2.5. --- X - ray briquettes --- p.88 / Chapter 3.2. --- Results and discussion --- p.88 / Chapter 3.2.1. --- Fusion of siliceous materials --- p.88 / Chapter 3.2.2. --- Fusion of coal --- p.93 / Chapter 3.2.3. --- Accuracy and precision --- p.95 / Chapter 3.2.4. --- Real sample analysis --- p.99 / Chapter Chapter 4. --- Conclusion --- p.103 / Chapter 4.1. --- Comparison of XRF and AAS as analytical means in the cement industry --- p.103 / Chapter 4.2. --- The proposed fusion system --- p.105 / References --- p.107
12

Production and examination of low pressure sulfur microwave excited electrodeless discharge lamps

Childs, Allan Harold January 2010 (has links)
Digitized by Kansas Correctional Industries
13

Optically stabilized diode laser using high-contrast saturated absorption

Cuneo, Christopher J. 20 May 1994 (has links)
Doppler-free saturation spectroscopy in an optically thick atomic vapor is used in an optical-feedback configuration for two semiconductor diode laser systems. One laser system consists of an unmodifed, commercially available diode laser. The other laser system consists of a diode laser initially stabilized by optical feedback from a diffraction grating. In both cases a portion of a 780-nm diode laser beam passes through a heated rubidium cell and is retroreflected back to the laser. The optical feedback causes the laser frequency to be stabilized to a hyperfine transition within the Rb D��� line. The linewidth of the laser is also reduced as a result of the optical feedback. / Graduation date: 1995
14

THE SEARCH FOR THE 404 1/CM FLUORINE ATOM TRANSITION AND OTHER OBSERVED SPECTRA

Crane, Barry Duncan January 1980 (has links)
No description available.
15

Ion enrichment in aerosols produced by conventional nebulizers used in analytical atomic spectroscopy

Dillard, John Henry 12 1900 (has links)
No description available.
16

Use Of Different Gold Amalgamation Techniques In Mercury Determination By Cold Vapor Atomic Absorption Spectrometry/

Erdem, Arzu. Eroğlu, Ahmet E. January 2005 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology, İzmir, 2005. / Keywords: Mercury, atomic absorption spectrometry, gold, amalgamation, cold vapor. Includes bibliographical references (leaves 48-51).
17

Separation of trace antimony and arsenic prior to hydride generation atomic absortion spectrometric determination/

Yersel, Müşerref. Eroğlu, Ahmet E.thesis advisor. January 2005 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology, İzmir, 2005 / Includes bibliographical references (leaves 35-37).
18

On-chip atomic spectroscopy /

Conkey, Donald B., January 2007 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 2007. / Includes bibliographical references (p. 55-58).
19

The development of a method for the determination of microgram amounts of magnesium by atomic absorption

Taylor, John Douglas January 1963 (has links)
This thesis includes a description of modifications of the Hilger atomic absorption apparatus, which was used for most of the work. These modifications were restricted to the atomiser and burner, which were replaced by a modified "Eel" flame. photometer atomiser-burner and resulted in improved sensitivity and instrumental stability for the atomic absorption of magnesium. A comparison of the performance of this unit with that of the unmodified Hilger apparatus is given. A "Handigas" butane-propane mixture)-air flame was used for most of this work, but a coal-gas-air flame was also studied and found to give slightly greater sensitivity. The method was found to be subject to interference from many elements. Strontium salts, employed as releasing agents to overcome the effect of other elements, were not completely effective as milligram amounts of several elements interfered even when strontium was present. Among the more serious interfering elements are: aluminium, iron, manganese and zirconium (less than 20 p.p.m. interfere); the alkali and alkaline earth metal salts (more than 200-500 p.p.m. interfere); phosphate (more than 100 p.p.m. P₂0₅ uranium (more than 4,000 p.p.m.); arsenate and vanadate. An attempt is made to explain the mechanism of some of these interfering effects. A combination of strontium salt and acetyl acetone was found to over-come the effects of small amounts of several elements that form complexes with acetyl acetone (e.g. iron and aluminium) far more effectively than strontium alone. Larger amounts of many interfering elements are removed by a solvent extraction procedure employing acetyl acetone and chloroform. Elements which cannot be removed by this means may be separated by anion-exchange, volatilisation, electrolysis or precipitation. A spiking technique, which compensates JT/GB for the effects of small amounts of interfering elements, is described and enables many samples to be analysed without prior separations. The method described has good sensitivity (the limit of determination is approximately 1 microgram of magnesium in 50 ml. of solution). It has been applied to the analysis of clay samples, iron ore, limestone and uranium metal, oxides and processing solutions. The coefficient of variation of the method was determined using two clay samples and results of 2.0 and 4.6 percent, at magnesium oxide concentrations of 0.65 and 0.22 percent respectively, wore obtained. The speed of the method compares favourably with others described for the determination of microgram amounts of magnesium, but increases if large amounts of interfering elements are present.
20

Optimisation and evaluation of boron analysis for pressurized Water reactor plants

Tasana, Nomalanga Gloria January 2016 (has links)
Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2016. / Boron concentration analysis is an important and critical analysis performed by the Analytical Chemistry Laboratory at Koeberg Nuclear Power Station (KNPS), because boron controls reactivity and the concentration determination is a Technical Specification Parameter (safety parameter). Hence accurate, precise results for boron concentration produced by laboratories and on-line analysers are important because of their operational implications associated with reactivity control and also for nuclear safety. The project focused on comparing the quality of chemical analysis results of boron produced by analysis techniques/ methods used at Koeberg Nuclear Power Station namely; Potentiometric Titration, Atomic Absorption Spectrophotometry (Flame) and UV-VIS Azomethine-H method. The methods were described, optimised, evaluated and compared in terms of uncertainty of measurement, accuracy, precision, analysis range, limitations, appropriateness and applicability for boron analysis in 2500 mg B/kg concentration range. For Potentiometric Titration method, the measurement uncertainty = 2500 ±16 mg B/kg, accuracy= 0.2%, precision= 0.08% the range of analysis= 5-800 mg B/kg. For Atomic Absorption Spectrophotometry (Flame) the measurement uncertainty= 2500 ±51 mg B/kg, accuracy= 0.12%, precision= 0.44% the range of analysis= 0 -500 mg B/kg. For UV-VIS Azomethine-H the measurement uncertainty= 2500 ±72 mg B/kg, accuracy= 0.08%, precision= 0.44% the range of analysis= 0 -10 mg B/kg. The INPOs 95% accuracy and precision criteria for boron is ± 1%. So these techniques could be used for boron analysis in PWR. Based on the evaluation and assessments mentioned above; the Potentiometric Titration was found to be the most preferred method for boron analysis for Pressurised Water Reactors followed by Atomic Absorption Spectrophotometry (Flame) that can be of good use in determining boron especially in waste samples and samples with complex matrices. The UV-VIS Azomethine-H methods can only be used when it is really necessary to determine very low levels of boron between 0- 10mg B/kg of which it was never required before. Since it is specifically the B-10 isotope that is responsible for the ability to control reactivity, the implementation of isotopic boron analysis (by Inductively Coupled Plasma – Mass Spectrometry) at KNPS is explained and the advantage of the programme is illustrated. Although the current state of instrumental capabilities is adequate for 10B isotope determination, further work of optimising the methodology for even better results is recommended.

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