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In this thesis, literature on the production, microstructures and properties of bulk metallic glasses (BMG) has been reviewed with particular reference to glass forming ability (GFA) and alloys of the Fe-Zr-B and Zr-based BMG systems. The experimental procedures used in the research are presented and the results for the amorphous Fe80Zr12B8 ribbon and the Zr57Ti5Al10Cu20Ni8, Zr57Nb5Al10Cu20Ni8, Zr53Nb2Al8Cu30Ni7 BMGs are given and discussed. Wedge-shaped ingots of the Zr-based BMGs were produced by casting in air or water cooled copper moulds. The Zr-based BMGs were fully amorphous up to 2 mm thickness of the wedge. In the Fe80Zr12B8 alloy and the Zr-based BMGs the glass transformation and crystallization temperatures increased with increasing temperature increase rate in the DSC. This shows that atom mobility dominates the onset of crystallization. Using XRD and TEM, the crystallization of the Fe80Zr12B8 amorphous alloy was studied from room temperature to 1273 K. The phase evolution path during continuous heating was: Amorphous → amorphous + alpha-Fe → amorphous + alpha-Fe + Fe23Zr6 (Fe3Zr) → amorphous + alpha-Fe + Fe23Zr6 (Fe3Zr) + Fe2Zr → amorphous + alpha-Fe + Fe23Zr6 (Fe3Zr) + Fe2Zr + Fe3B. In the air-cooled Zr57Ti5Al10Cu20Ni8 alloy the A1 rich Zr3Al2 and the bcc Al1.5(Cu+Ni)3(Zr+Ti)5 phases were quenched in the amorphous matrix and as the temperature decreased nanocrystalline Zr3Al2 phase nucleated. It is suggested that A1 is critical regarding GFA. The main crystalline phase that contained Zr, Ti, Al, Cu and Ni was the tetragonal (Zr, Ti)2(Cu, Al, Ni) phase, which is isomorphous with the Zr2Cu phase. Compared with the air-cooled alloy, the water-cooled amoiphous Zr57Ti5Al10Cu20Ni8 alloy has a larger supercooled liquid region and the same reduced glass transition temperature. This would suggest that fine crystallites were probably present in the air-cooled amorphous Zr57Ti5Al10Cu20Ni8 alloy. Thermal stability and GFA increased with the substitution of Ti with Nb in Zr57Nb5Al10Cu20Ni8 and the increase of the Cu/Nb ratio in Zr53Nb2Al8Cu30Ni7. Increase of the Cu/Nb ratio in Zr-based BMGs improved the GFA criteria, the thermal stability, hardness and eliminated crack formation. It is suggested that the Zr-Ti/Nb-Al-Cu-Ni BMGs with high glass forming ability can be obtained over a wide composition range Zr = 50-60 at.%, Ti or Nb = 2-5 at.%, A1 ≤ 8 at.%, Cu+Ni ≥ 30 at.%. On the basis of the results of this study on the formation of the primary crystallization phase, it is suggested that atomic packing close to the amorphous phase, high melting temperature and strong bonding among component elements lead to the ease of formation of the primary phase. In terms of reliability and applicability, good glass formers should capture the following features: low Ti, high Tg and high (Tx-Tg). Good indicators are made of ratios and sums of ratios that reflect these features. New GFA indicators are proposed namely: Tx/Tg + Tx/T1, Tx/(T1-Tg) + Tx/Tg, Tx/Tg + Tg/T1 +Tx/T1, (Tx-Tg)/T1 + Tx/T1. Casting at specific cooling rate or annealing at temperature between the glass transition temperature (Tg) and onset crystallization temperature (Tx), especially annealing near Tx for enough time, leads to the formation of nanoparticles in an amorphous matrix.

This study endeavored to provide a new path to understand Fusheng liu ji (Six Chapters of a Floating Life) by Shen Fu in the middle of the Qing Dynasty (1636-1911). Shen Fu recorded his love story with his wife Chen Yun and his life as a Chinese literatus in his memoir, which had originally six chapters but only four survived. The characteristics of the couple and their artistic way of living were admired so much by many readers, among them was Lin Yutang, who translated Fusheng liu ji and used it as demonstration of Taoist philosophy and the Chinese traditional way of living. Although Fusheng liu ji is generally known as one of the best autobiographical works in the pre-modern time and loved by readers in and outside of China, some important questions have not been addressed, including the reception history of it, the literati identity of Shen Fu and Chen Yun, and the true meaning of their artistic creations. All these questions are scrutinized and explored in this dissertation. This study uses several scholars who lived in three periods of time (respectively at the end of the nineteenth century and the beginning of the twentieth century, the 1920s through the 1940s, and the 1980s and after) as examples to explore the reception history of Fusheng Iiu ji. This study also analyzes the synchronic context of the book including the location of different gaps in the text and their functions. Furthermore, this study discusses the literati identity of Shen Fu and Chen Yun, and also on their most courageous creation: the playing of literati throughout their lifetime. By doing so, this study provides an insightful glimpse on the meaning of the Chinese artistic way of living. Wolfgang Iser's theory of "gaps," as well as the social construction of reality theory of Peter Berger and Thomas Luckmann, and the thoughts on "play" of Hans-Georg Gadamer, are used as guidelines in this study. The author of the current dissertation hopes this study can facilitate the further understanding of the Chinese mentality and artistic spirit demonstrated in Fusheng liu ji.

Atherogenesis shares many features with inflammatory and immunal reactions. Bacterial endotoxin (LPS), together with T-lymphocytes cytokine interferon-gamma (IFNγ), causes inflammation and immune response. Because of its strategic anatomic position, endothelial cells are a primary target for injury and cardiovascular risk factors. A simple method for isolating and culturing mouse aortic endothelial cells (MAEC) was developed for studying the endothelial injury and activation by these stimuli in vitro (Section I). The effects of LPS and IFN, in the absence and presence of hypercholesterolemia, a traditional risk factor for atherosclerosis, on endothelial function and pro-inflammatory gene expression in vivo were also studied (Section II). We found that LPS and IFN synergistically activated MAEC by upregulating pro-inflammatory genes, such as inducible nitric oxide synthase and vascular cell adhesion molecule-1. Several signal transduction pathways, such as the Janus kinase/signal transducer and activator of transducer-1 (STAT1), the p38 mitogen-activated protein kinase, and the protein kinase A pathways, were involved in this regulation. Other effects of LPS included inducing the production of superoxide anion and hydrogen peroxide by MAEC. These reactive oxygen species, especially oxidized low-density lipoprotein cholesterol, caused MAEC injury, DNA breakage and gene expression. The in vivo effects of inflammation in endothelial dysfunction and atherogenesis were studied using a mouse model (C57BL/6) on an atherogenic diet. A single low dose of LPS (1.0 mg/kg, intraperitoneal injection) caused an impairment of endothelial-dependent vasorelaxation in response to acetylcholine in these mice but not their normal diet fed littermates. Endothelial-independent vasorelaxation remained unaffected. Chronic treatment with LPS (once a week for 12 weeks) or 16-week of the atherogenic diet each caused endothelial dysfunction. A more significant effect was observed with the combination of a low dose of LPS (0.5 mg/kg) and the atherogenic diet. The impairment of endothelial function by the atherogenic diet was lesser in STAT1 knockout mice. Overall, our results presented here suggest that multiple factors, such as inflammation, oxidation, and hypercholesterolemia, are involved in endothelial cell activation and dysfunction. These mechanistic insights of endothelial biology will provide new therapy for the cardiovascular disease, especially atherosclerosis.