Hydrothermal fluids near and above the critical point of water have unique and potentially very useful thermophysical properties. At present, the lack of knowledge of supercritical water chemistry hinders implementation of innovative hydrothermal technologies. The development of new experimental methods and application of molecular modeling tools is clearly warranted to provide a better understanding of the complex properties of aqueous systems at elevated temperatures and pressures. The thermodynamic, dielectric and transport properties of hydrothermal fluids are investigated using Molecular Dynamics (MD) simulation and flow injection techniques. The spatial hydration structures and self-diffusion coefficients of phenol, aniline and naphthalene in aqueous infinitely dilute solution are examined from ambient to supercritical conditions by means of MD simulations. It is shown that the solvation shell around aromatic molecules undergoes significant changes along the liquid-vapour coexistence curve and, essentially, disappears at supercritical conditions. The changes in hydration structures are reflected in the values of the self-diffusion coefficients which dramatically increase near the critical point of water. The thermodynamic and dielectric properties of the Simple Point Charge Extended (SPC/E) water model are examined over a broad range of sub- and supercritical states. Accurate thermodynamic and dielectric equations of state (EOS) for the SPC/E water model are presented. The parameterizations provide the most accurate, up-to-date description of the properties of high-temperature SPC/E water, thus enabling for the direct comparison of molecular simulation results with experimental data via the corresponding states principle. The experimental methodology for the study of aqueous fluids at extreme conditions by using the ex situ flow injection technique is presented. The methodology significantly simplifies the technical aspects of flow injection analysis in hydrothermal fluids as sample injection and detection are performed at ambient temperature, thus allowing the use of standard on-line detection methods. The proposed ex situ experimental technique is applied to the examination of the hydrodynamic regime of a flow-through tubular reactor from ambient to supercritical water conditions. Application of the ex situ Taylor dispersion technique to measurements of the binary diffusion coefficients in hot compressed water is also presented. The ex situ flow injection methodology provides a basis for further development of flow injection analysis techniques at supercritical water conditions. / Thesis (Ph.D, Chemistry) -- Queen's University, 2009-03-05 17:39:30.197

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Background Adolescents and adults suffering from needle phobia have an unreasonable fear of needles that leads to negative experiences if they do not get the support they need. Negative experiences lead to patients avoiding health care, or these experiences affect important aspects of life. The suffering that a patient experiences may be obvious to some, but others hide it, and then it will be more difficult to detect. The nurse's role is to recognize the suffering and its different reactions in order to alleviate and prevent unnecessary suffering of the patient. AimThe purpose of this study was to describe about young people's and adults' experiences of having needle phobias. Method A literature review methodology, using eight quantitative articles and one qualitative article relevant for the aim of study.The analysis was done by comparing the similarities and differences from the result's content.Afterwards the most important parts in the result was coded to build categories and themes. Results Patients with needle phobias experience many different physical reactions such aspain, vasovagal reaction and other reactions during venipuncture, injections or just by seeing a needle. Long waiting times worsened the experience and strengthened the response. Patients experience more anxiety and fear because of their previous negative experiences and because of the medical environment. Experiences and reactions differ between ages, gender and level of education. Conclusion Patients with needle phobias have different experiences and reactions vary from person to person. Nurses on care institutions need more knowledge about patient'sexperiencesof needle phobias to better support and ease the suffering that afflicts the patients.

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