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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.

Studies of equilibria involving chloro-complexes of iodine

Cason, Dennis Lamar 08 1900 (has links)
No description available.

Dissolved inorganic and particulate iodine in the oceans /

Wong, George Tin Fuk. January 1976 (has links)
Thesis--Massachusetts Institute of Technology/Woods Hole Oceanographic Institution Joint Program in Oceanography. / "WHOI-76-106." Includes bibliographical references (p. 235-250).

Iodine metabolism in insects

Limpel, Lawrence Eugene, January 1957 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1957. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 52-54).

A study of the solvent effect on the iodination of olefins

Geerts, Marcellus Joseph. January 1939 (has links)
Thesis (Ph. D.)--University of Notre Dame, August 1939. / Bibliography, p. 42-43.

Iodine in bovine milk

Ruegsegger, Gary J. January 1981 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1981. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 47-51).

Reactions of iodine excited by 185 nm radiation in the gas phase and in hydrocarbons at 77K̊

Glasgow, Louis Cahrles, January 1970 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.

Optical properties of potassium iodide in the far-infrared

Kembry, Kenneth Allen January 1974 (has links)
Measurements and calculations of the far-infrared optical properties of K ³⁹I at 300, 77, and 12*K are presented. The measurements are mainly those of absorption in crystals of various thicknesses. The calculation assumed cubic anharmonicity only, with nearest-neighbour coupling, and the input lattice-dynamlcal data were obtained from a shell-model program. These data were generated with a wave vector density of 32000 points per zone, which, was sufficient to give 2-3 cm⁻¹ resolution. The over-all agreement between experiment and theory, in both: the intensity and structure of the spectra, is good. The magnitude of certain calculated features is, however, too large, indicating a need to consider next-nearest-neighbour interactions. Evidence was also found for three-phonon damping, both beyond the two-phonon limit at all temperatures and at J[sub o] by 300°K. From these measurements it was possible to calculate portions of the three-phonon damping spectra, which were found to be reasonable. The higher-phonon effects at 300°K did not seem to be noticeably more pronounced than those found in the much harder LiF, and arguments are presented to understand this. Finally, the isotope-induced one-phonon processes which occur in natural KI were calculated. These are shown to be small away from the resonance frequency v, and not to be the major damping mechanism at V[sub e] at low, temperatures^ in contrast to Lif. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

Nonlinear resonant photoionization in molecular iodine

Sil, Georgena Sarah Petty January 1976 (has links)
Strong photoionization spectra have been observed in molecular Iodine following laser excitation in the near ultraviolet. The dependence upon laser power, and the structure of the spectra are consistent with three-photon ionization with resonance in an intermediate state excited by two photons. Vibrational analysis indicates an electronic energy T[sub e] of 53,562.75 ± 1 cm⁻¹, a harmonic vibrational constant we of 241.4 ± 0.4 cm⁻¹, and an anharmonic vibrational constant toexe of 0.58 ± 0.06 cm⁻¹. Rotational analysis done by the Franck-Condon method, whereby the relative experimental band intensities are compared with theoretical values, indicates that the internuclear separation r[sub e] in the resonant electronic state is 2.567 ± 0.002A, corresponding to a rotational constant B of 0.04029 ± 0.00007 cm⁻¹. The new electronic state has, with high probability, the designation 1[sub g] . Several im purity lines were observed at exciting energies 26,297.14 ± 1 cm⁻¹ (half width 8.09 cm⁻¹), at 26,915.22 ± 1 cm⁻¹, and at 27,343.96 ± 1 cm⁻¹. The impurity signal varies as I[sub o][sup 2.02]. The features likely arise from complex molecular species formed in reactions at high temperature with l₂, and have not been identified. The photoionization efficiency of in nonlinear absorption exhibits an apparent resonance in the vicinity of 80,000 cm⁻¹ in terms of total molecular energy. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

An Assesement of Iodine-129 and Iodine 127 in Human Biological Materials with Modelling of Dietary Iodine Intake and Excretion

Almarshadi, Fahad Awwadh 03 June 2022 (has links)
This thesis concerned with iodine status, sources in human body, and measurements especially here in Canada, where iodine status for the Canadian population is not well known. With the recent re-emergence of iodine deficiency among individuals in other industrial countries, understanding the main sources of iodine to the Canadian population is necessary to ensure fortification strategies are justified and effective. Uncertinaty has arisen to the importance of iodized salt recently, along with medical warnings to reduce salt consumbtion. This conflicts give rise to improve scientific research and hone thier methods with new applications. The research question here is that: Can we benefit from the existence of long-lived radioiodine-129 in the environment and explore its potential as a tracer? To answer this question, the study was divided into an introductory chapter contains a review about the topic, then three research chapters. The second chapter was devoted to study the possibility of extracting 129I from human urine. As for third chapter of the thesis, it was about refining a method that already established, and use it to extract 129I from breastmilk using combustion, then determine the radiological dose of 129I in infants’ thyroid. While the fourth chapter was devoted to investigate the main sources of 127I and 129I in the Canadian diet based on daily food consumption and modelling the urinary iodine concentration for adults and infants through the novel application of a well-established compartment model implemented in AMBER. The path of this thesis was crowned with a set of results, which are detailed in the end of each chapter as follow: 1- The advantage of accelerator mass spectrometry (AMS) helps to measure 129I in human urine for the first time. The result for 25 participants from Ottawa ranged from 3.3 x 106 atoms/L to 884 x 106 atoms/L with a median of 108.7 x 106 atoms/L, and the 129I/127I ratio ranged from 7.38 x 10-12 to 3.97 x 10-10 with a mean of 1.3 x 10-10. 2- The concentration of 127I and 129I in Ottawa urine samples were significantly correlated and generally similar to the 129I concentrations and 129I/127I ratios from environmental samples collected around Ottawa. 3- This correlation suggests that 129I could be a potential nutritional tracer of dietary iodine. 4- In chapter 3, the 129I in breastmilk ranged from 1.26x108 atoms/L to 6.64x108 atoms/L with a median of 2.10 x108 atoms/L, and the 129I/127I ratio ranged from 1.27x10-10 to 9.9x10-10 with a median of 2.13x10-10. 5- A correlation was also observed between 127I and 129I concentrations in breastmilk. 6- The isotopic ratios in breastmilk were similar to Canadian cow’s’ milk, indicating that the milk of both cows and humans is a reflection of the 129I concentration of their local environment and the food ingested. 7- Result from chapter 3 confirms that humans are exposed to the 129I from birth through their mother breastmilk, giving them an average dose of 1.10 x10-4 Bq/year and thyroid dose rate equal to 5.92 x10-10 Sv/year. 8- In fourth chapter, the daily milk consumption was measured for 78 mother-infants’ pairs, and ranged from 275 -1202 g/day, with a mean of 731 g/day. This value agrees well with global infant milk intake which estimated at 730g/day. 9- The daily iodine intake from breastmilk ranged from 11.2 µg/day to 476.2 µg/day with a median of 127.9 µg/day. 10- The urinary iodine concentrations were estimated without urine collection using iodine biokinetic model, giving a median urinary iodine concentration (n=78) at 304.7 µg/L. The result was compared to those measured by Health Canada (median= 398.7 µg/L), showing a moderate correlation (r= 0.496). 11- A further comparison of the results was made based on gender shows that the difference between UIC in male and female infants measured by Health Canada and those estimated by AMBER is non-significant. 12- Through AMBER software, the influence of seven common diets on UICs was assessed to determine which foods play an important role in ensuring iodine adequacy. We observed that the main source of iodine in a vegan diet is grain products providing up to 70%, while in remaining diets the main source of iodine was dairy products (50-69%) when they are consumed. 13- The contribution of iodized salt to all Canadian diets was ranked second, after dairy, unless the diet is vegan or ovo-vegetarian, where dairy is not consumed, iodized salt was ranked first. 14- Among 23 scenarios for seven different diets, the urinary iodine-129 concentrations ranged from 1.4 x10-7 to 3.3 x10-7 µg/L with a median of 3.1 x10-7 µg/L, and the isotopic 129I/127I ratio ranged from 1.1 x10-9 to 1.2 x10-8 with a median of 2.8 x10-9. 15- In contrast to stable iodine, the highest isotopic ratio was observed in vegan diet, while the lowest was observed in ketogenic diet. This suggests that grain products are the main contributor of 129I to humans. 16- Despite being the primary contributors of stable iodine (127I), salt and dairy show a lower contribution of 129I. Based on this we can qualitatively predict the source of iodine 127 using isotopic ratio 129I/127I. For example, in cases where the isotopic ratio was between 10-8 and 10-9, therefore, the main sources of iodine in this person may be from grains products, vegetables, and fruits; and in cases where the isotopic ratio was between 10-10 and 10-11, therefore, the main sources of iodine in this person may be from dairy products and some contribution from salt. This study has shown the capability of 129I to be used in biomedical fields. In this thesis 129I used as a nutritional tracer where it helps to detect the sources of stable iodine in human body based on isotopic ratio. The extraction method invented in Chapter 2 can be used to evaluate 129I exposure directly in the human body for those who live nearby nuclear fuel reprocessing plants. An additional application for this method can be in assessing 129I in human to investigate 131I uptake in the event of a nuclear emergency using 129I in urine as a proxy. Moreover, the extraction technique used Chapter 3, can be extended to other biological samples such as thyroid or brain. Furthermore, Chapter 4 shows that with the right estimation of daily iodine intake and urine volume, a biokinetic model of iodine, built in the AMBER software, can predict urinary iodine concentration with a high degree of accuracy without collecting urine samples.

Studies in the determination of iodine in soils organic materials, and waters

Lundell, Russell T. 01 August 1946 (has links)
A summary of the literature on the nutritional value of iodine in the diet of various forms of life is given. The majority of evidence indicates that iodine is an essential element in plant and animal nutrition. It functions particularly in animal metabolism in the form of thyroxine. The occurrence of iodine in a nature has been briefly discussed. Investigations made in this regard indicate iodine to be almost universally distributed in very minute amounts. Most iodine salts are soluble in water and their distribution is affected by water movements. Results of iodine determinations made during the course of this study support this idea. This investigation also supports the concept that iodine is taken up by life forms and its distribution thereby affected. As one might expect, the problem of the quantitative determination of a substance occurring in such minute amounts presents a difficult problem. A brief outline of the history of the development of analytical methods with particular emphasis on the oxidation of organic material and the liberation of iodine is recorded in this theses. A particular wet ashing method has been investigated and modifications have been made to increase its reliability and simplify its techniques. The modifications involving both the oxidizing process for the destruction of organic material, and the control of the distillation process are based on experimental data and experience gained during this study. The applicability of the method in its modified form to a wide range of materials has been demonstrated experimentally. A limited survey of the iodine content of the soils of a given portion of Utah County has been made and the iodine content correlated with the soil type and alkalinity. The writer is not aware of any other iodine analyses of Utah soils. It is probable that further iodine analyses of soils in the Great Basin area with respect to geologic origin, water movements and soil organisms would yield data of interest in the goiter problem of this area.

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