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Scholars have long recognized the influence of canonical Indian tantras and their attendant sādhanas and vidhis on the formation of new Buddhist traditions in Tibet. The impact of the more popular tantric preliminaries has, however, received far less attention. This dissertation argues that the Tibetan preliminary practices that are so widespread today are historically rooted in the rise of the lay tantric guru. In early medieval India, lay gurus were controversial, so much so that even a well-known collection of devotional practices for relating to such figures—Fifty Verses on the Guru—cautions against bowing to them in public. In eleventh- and twelfth-century Tibet, however, influential lay lamas came to serve as respected heads of monastic institutions. Throughout this period, preliminary practices were an important site for innovation, where Indians and Tibetans alike worked out the changing place of the guru within Buddhism. In Tibet, the popularization of preliminary rites such as guru yoga (bla ma’i rnal ‘byor) reflected the elevated status of the lama in the new (gsar ma) Buddhist schools. By the thirteenth century, preliminary practice systems (sngon ‘gro) that were almost entirely focused on the lama—lay or monastic—had become a mainstay of Tibetan Buddhism.

The Laser Ablation of Microparticle Aerosol (LAMA) system in the Nanoparticle Research group at the University of Texas at Austin contains an aerosol density sensor (ADS) component that is critical to achieving accurate results when studying nanoparticle properties. The current ADS at work in the system has been found to possess some data accuracy concerns and a certain lack of usability. To improve on the design, a project was initiated to study the existing sensor to determine the weaknesses of the current design, derive a specific set of requirements for a new sensor, and complete the design and testing of a new ADS for use in the LAMA system. Overall, several major design areas were altered. A completely new LabVIEW data acquisition and processing application was created to monitor, log, and display the density data to the operator, several mechanical components were given additional features to preserve the density signal of the sensor, and the low-voltage DC power supply and signal processing circuitry were significantly redesigned. Advanced testing was performed on the final product to verify that it meets all requirements of the research group and is both reliable and accurate.

Amorphous metals have been discovered in 1960 and, because of their structures, exhibit very unique mechanical, magnetic and chemical properties that can have various applications. These properties qualify them as the potential material of the future. This work focuses on a new laser ablation technique to synthesize nanoparticles of amorphous metals from aqueous feedstock. One of the critical factors in the production of amorphous metal is the cooling rate used to synthesize them. The laser ablation of microparticle aerosol (LAMA) process used in this work, with a cooling rate estimated of 10¹² K/s, has all the characteristics required for the production of such metallic glasses. A Collison nebulizer is used to generate microdroplets of a nitrate solution containing the corresponding ratio of metals for the production of a Zr-Al-Ni based alloy. Once dried and conditioned, these microdroplets leave solid microparticles which are ablated by an excimer laser producing nanoparticles that are then filtered by virtual impaction. In order to characterize the nanoparticles obtained with this process nanoparticulate films produced by LAMA have been analyzed by optical profilometry, scanning electron microscopy (SEM) equipped with energy-dispersive x-ray spectroscopy (EDS) and transmission electron microscopy (TEM) equipped with EDS. The results agree with a hypothesis that the films contain oxidized, amorphous metal on the surface of the films. When the films are thin, they are fully oxidized, and simultaneous segregation of Zr occurs to the surface. The hypothesis and the results are discussed.

The Laser Ablation of Microparticle Aerosols (LAMA) process produces nanoparticles by ablating microparticles that are entrained in an aerosol. Two of the main advantages of this process are that the particles produced are charged (preventing agglomeration) and bare (without a capping layer). Two different techniques are possible to collect the nanoparticles. In this work, the charged state of the particles formed was utilized to collect them electrostatically. This approach has the additional advantage that particles can be selected according to their size. The focus here was a particular application for gas separation. The nanoparticles produced were directly collected in a polymeric liquid, which was then irradiated with ultraviolet light to form a rubbery film. These membranes were tested for olefin/paraffin gas separation, a challenge that finds many applications, notably in the petroleum industry.

This dissertation presents a complete translation and critical edition of the autobiography of the Tibetan Buddhist lama Yol mo Bstan 'dzin nor bu (1598-1644). Entitled The Sarangi with the Vajra Sound, Bstan 'dzin nor bu's autobiography provides a unique perspective on the religious, cultural, and political contexts of the early seventeenth century. A series of essays addressing important themes in the autobiography introduces the translation through critical readings placing the text within the wider fields of Buddhist literature, doctrine, and practice. Chapter One considers the tension between the doctrine of the emanation body (sprul sku) and the social institution of the recognized rebirth (yang srid) through the autobiographical account of Bstan 'dzin nor bu's childhood. The author's literary reconstructions of his memories of present and previous lives are explored as grounds for an analysis that seeks to recover the salience of individual agency as a factor in social and religious history. Chapter Two examines the categories of monk and the tantric priest (sngags pa) through a review of their role as an organizing dichotomy in representations of Tibetan Buddhism. The stark opposition and antipathy generally afforded to these two religious occupations is challenged through a close reading of Bstan 'dzin nor bu's account of his transformation from the former to the latter. This reading reveals that Bstan 'dzin nor bu addresses this shift not in terms of doctrinal view or soteriological practice, but rather in terms of physical comportment and social identity. Chapter Three addresses Bstan 'dzin nor bu's career as a sngags pa by focusing upon his interactions with several of the leading political figures of his time. Chapter Four offers reflections on the author's stated reasons for composing the autobiography and revisits the questions of memory, agency, and identity raised in the previous essays. Chapter Five consists of a complete translation of The Sarangi with the Vajra Sound. Annotations throughout the translation identify key individuals, institutions, locations, texts, and practices that appear in the autobiography. Chapter Six consists of a critical edition in the Tibetan dbu can script based upon three extant manuscripts in the dbu med script.