Thermodynamic description and phase transformation of highly symmetrical monoatomic structures

Based on theoretical considerations an explanation for the temperature dependence of the thermal expansion and the bulk modulus is proposed. A new equation state is also derived. Additionally a physical explanation for the latent heat of fusion is presented. These theoretical predictions are tested against experiments on highly symmetrical monatomic structures. ^ The volume is not an independent variable and must be broken down into its fundamental components when the relationships to the pressure and temperature are defined. Using zero pressure and temperature reference frame, the initial parameters, volume at zero pressure and temperature[V°], bulk modulus at zero temperature [K°] and volume coefficient of thermal expansion at zero pressure[α°] are defined. ^ The new derived EoS is tested against the experiments on perovskite and epsilon iron. The Root-mean-square-deviations (RMSD) of the residuals of the molar volume, pressure, and temperature are in the range of the uncertainty of the experiments. ^ Separating the experiments into 200 K ranges, the new EoS was compared to the most widely used finite strain, interatomic potential, and empirical isothermal EoSs such as the Burch-Murnaghan, the Vinet, and the Roy-Roy respectively. Correlation coefficients, RMSD's of the residuals, and Akaike Information Criteria were used for evaluating the fitting. Based on these fitting parameters, the new p-V-T EoS is superior in every temperature range relative to the investigated conventional isothermal EoS. ^ The new EoS for epsilon iron reproduces the preliminary-reference earth-model (PREM) densities at 6100-7400 K indicating that the presence of light elements might not be necessary to explain the Earth's inner core densities. ^ It is suggested that the latent heat of fusion supplies the energy required for overcoming on the viscous drag resistance of the atoms. The calculated energies for melts formed from highly symmetrical packing arrangements correlate very well with experimentally determined latent heat values. ^ The optical investigation of carhonado-diamond is also part of the dissertation. The collected first complete infrared FTIR absorption spectra for carhonado-diamond confirm the interstellar origin for the most enigmatic diamonds known as carbonado. ^

Ficcion de racionalidad: La memoria como operador mitico en las esteticas polares de Jorge Luis Borges y Jose Lezama Lima

The aesthetic placement and period designation of Jorge Luis Borges (1899–1986) and José Lezama Lima (1910–1976) are complicated issues among critics. Borges is considered a predecessor of the Latin American literary “boom,” but despite that taxonomy his work transcends that definition and provides a foundation for new trends, such as the “neobarroco” cultivated by Severo Sarduy. Lezama is considered part of the second wave of the “boom,” but his work feeds, stylistically, from the Spanish baroque. At the same time, Lezama's daring treatment of homoeroticism and his system of images place him after the “boom” in a narrative style that is postmodern. This study undertakes a revision of external and internal issues, revealing the key fictive elements that characterize both writers. Through discourse analysis, a poetic system is formulated, which incorporates features of the “neobarroco,” and postmodern narrative styles. ^ This dissertation uses a polar structure to analyze both poetic visions and finds that they are symmetrical. From this perspective, Borges and Lezama belong to the “core” of literature that centers its emphasis in the creation of a system versus other modes of writing in which mimetic function prevails. By doing this and by recycling world culture, they create postmodern myth: the new building material for Hispanic American literature. ^ There are a few studies that explore the works of Borges and Lezama within the context of Baroque aesthetics. This dissertation offers a comprehensive analysis that considers their poetic visions at large. Besides the difference in perspective, defined as macro-spatial in Borges and micro-spatial in Lezama, there are many similarities. Both writers question the cause and effect relationship and the use of metaphor. They share a redefinition of genre as well as a hedonistic approach to literature. This kinship in poetic vision is revealed through the polar method used for this study, which proposes a new form of aesthetic placement and period designation. ^

Ficción de Racionalidad: La memoria como operador mítico en las estéticas polares de Jorge Luis Borges y José Lezama Lima

The aesthetic placement and period designation of Jorge Luis Borges (1899-1986) and José Lezama Lima (1910-1976) are complicated issues among critics. Borges is obviously considered a predecessor of the Latin American literary “boom,” but despite that taxonomy his work transcends that definition and provides a foundation for new trends and styles, such as the “neobarroco” cultivated by Severo Sarduy. Lezama is considered part of the second wave of the “boom,” but his work feeds, stylistically, from the Spanish baroque. At the same time, Lezama’s daring treatment of homoeroticism and his revolutionary system of images place him after the “boom” in a narrative style that is postmodern. This study undertakes a thorough revision of external and internal issues, revealing the key linguistic and fictive elements that characterize both writers. Through discourse analysis and close reading, a poetic system is formulated, which incorporate features of the “neobarroco,” “boom” and postmodern narrative styles. This dissertation uses a polar structure to analyze both poetic visions and concludes that they are compatible and symmetrical. From this perspective, Borges and Lezama belong to the “core” of literature that centers its emphasis in the creation of a system versus other modes of writing in which mimetic function prevails. By doing this and by recycling world culture, they create postmodern myth: the new building material for Hispanic American literature. There are only a few studies that explore the works of Borges and Lezama within the context of Baroque aesthetics. For the first time, this dissertation offers a comprehensive analysis that considers their poetic visions at large. Besides the difference in perspective, defined as macro-spatial in Borges and micro-spatial in Lezama, there are many similarities in content and form. Both writers question the cause and effect relationship and the modern use of metaphor. They also share a redefinition of genre as well as a hedonistic approach to literature and culture. This kinship in poetic vision is revealed through the polar method used for this study, which proposes a new form of aesthetic placement and period designation.

Novel approaches for the synthesis of C-5 modified pyrimidine nucleosides

The antiviral or anticancer activities of C-5 modified pyrimidine nucleoside analogues validate the need for the development of their syntheses. In the first half of this dissertation, I explore the Pd-catalyzed cross-coupling reaction of allylphenylgermanes with aryl halides in the presence of SbF 5/TBAF to give various biaryls by transferring multiple phenyl groups, which has also been applied to the 5-halo pyrimidine nucleosides for the synthesis of 5-aryl derivatives. To avoid the use of organometallic reagents, I developed Pd-catalyzed direct arylation of 5-halo pyrimidine nucleosides. It was discovered that 5-aryl pyrimidine nucleosides could be synthesized by Pd-catalyzed direct arylation of N3-free 5-halo uracil and uracil nucleosides with simple arenes or heteroaromatics in the presence of TBAF within 1 h. Both N3-protected and N3-free uracil and uracil nucleosides could undergo base-promoted Pd-catalyzed direct arylation, but only with electron rich heteroaromatics. ^ In the second half of this dissertation, 5-acetylenic uracil and uracil nucleosides have been employed to investigate the hydrogermylation, hydrosulfonylation as well as hydroazidation for the synthesis of various functionalized 5-vinyl pyrimidine nucleosides. Hydrogermylation of 5-alkynyl uracil analogues with trialkylgermane or tris(trimethylsilyl)germane hydride gave the corresponding vinyl trialkylgermane, or tris(trimethylsilyl)germane uracil derivatives. During the hydrogermylation with triphenylgermane, besides the vinyl triphenylgermane uracil derivatives, 5-[2-(triphenylgermyl)acetyl]uracil was also isolated and characterized and the origin of the acetyl oxygen was clarified. Tris(trimethylsilyl)germane uracil derivatives were coupled to aryl halides but with decent yield. Iron-mediated regio- and stereoselective hydrosulfonylation of the 5-ethynyl pyrimidine analogues with sulfonyl chloride or sulfonyl hydrazine to give 5-(1-halo-2-tosyl)vinyluracil nucleoside derivatives has been developed. Nucleophilic substitution of the 5-(β-halovinyl)sulfonyl nucleosides with various nucleophiles have been performed to give highly functionalized 5-vinyl pyrimidine nucleosides via the addition-elimination mechanism. The 5-(β-keto)sulfonyluracil derivative has also been synthesized via the aerobic difunctionalization of 5-ethynyluracil analogue with sulfinic acid in the presence of catalytic amount of pyridine. Silver catalyzed hydroazidation of protected 2'-deoxy-5-ethynyluridine with TMSN3 in the presence of catalytic amount of water to give 5-(α-azidovinyl)uracil nucleoside derivatives was developed. Strain promoted Click reaction of the 5-(α-azidovinyl)uracil with cyclooctyne provide the corresponding fully conjugated triazole product.^

Computer program for the analysis of non-prismatic beams

One of the major problems in the analysis of beams with Moment of Inertia varying along their length, is to find the Fixed End Moments, Stiffness, and Carry-Over Factors. In order to determine Fixed End Moments, it is necessary to consider the non-prismatic member as integrated by a large number of small sections with constant Moment of Inertia, and to find the M/EI values for each individual section. This process takes a lot of time from Designers and Structural Engineers. The object of this thesis is to design a computer program to simplify this repetitive process, obtaining rapidly and effectively the Final Moments and Shears in continuous non-prismatic Beams. For this purpose the Column Analogy and the Moment Distribution Methods of Professor Hardy Cross have been utilized as the principles toward the methodical computer solutions. The program has been specifically designed to analyze continuous beams of a maximum of four spans of any length, integrated by symmetrical members with rectangular cross sections and with rectilinear variation of the Moment of Inertia. Any load or combination of uniform and concentrated loads must be considered. Finally sample problems will be solved with the new Computer Program and with traditional systems, to determine the accuracy and applicability of the Program.

Novel Approaches for the Synthesis of C-5 Modified Pyrimidine Nucleosides

The antiviral or anticancer activities of C-5 modified pyrimidine nucleoside analogues validate the need for the development of their syntheses. In the first half of this dissertation, I explore the Pd-catalyzed cross-coupling reaction of allylphenylgermanes with aryl halides in the presence of SbF5/TBAF to give various biaryls by transferring multiple phenyl groups, which has also been applied to the 5-halo pyrimidine nucleosides for the synthesis of 5-aryl derivatives. To avoid the use of organometallic reagents, I developed Pd-catalyzed direct arylation of 5-halo pyrimidine nucleosides. It was discovered that 5-aryl pyrimidine nucleosides could be synthesized by Pd-catalyzed direct arylation of N3-free 5-halo uracil and uracil nucleosides with simple arenes or heteroaromatics in the presence of TBAF within 1 h. Both N3-protected and N3-free uracil and uracil nucleosides could undergo base-promoted Pd-catalyzed direct arylation, but only with electron rich heteroaromatics. In the second half of this dissertation, 5-acetylenic uracil and uracil nucleosides have been employed to investigate the hydrogermylation, hydrosulfonylation as well as hydroazidation for the synthesis of various functionalized 5-vinyl pyrimidine nucleosides. Hydrogermylation of 5-alkynyl uracil analogues with trialkylgermane or tris(trimethylsilyl)germane hydride gave the corresponding vinyl trialkylgermane, or tris(trimethylsilyl)germane uracil derivatives. During the hydrogermylation with triphenylgermane, besides the vinyl triphenylgermane uracil derivatives, 5-[2-(triphenylgermyl)acetyl]uracil was also isolated and characterized and the origin of the acetyl oxygen was clarified. Tris(trimethylsilyl)germane uracil derivatives were coupled to aryl halides but with decent yield. Iron-mediated regio- and stereoselective hydrosulfonylation of the 5-ethynyl pyrimidine analogues with sulfonyl chloride or sulfonyl hydrazine to give 5-(1-halo-2-tosyl)vinyluracil nucleoside derivatives has been developed. Nucleophilic substitution of the 5-(β-halovinyl)sulfonyl nucleosides with various nucleophiles have been performed to give highly functionalized 5-vinyl pyrimidine nucleosides via the addition-elimination mechanism. The 5-(β-keto)sulfonyluracil derivative has also been synthesized via the aerobic difunctionalization of 5-ethynyluracil analogue with sulfinic acid in the presence of catalytic amount of pyridine. Silver catalyzed hydroazidation of protected 2'-deoxy-5-ethynyluridine with TMSN3 in the presence of catalytic amount of water to give 5-(α-azidovinyl)uracil nucleoside derivatives was developed. Strain promoted Click reaction of the 5-(α-azidovinyl)uracil with cyclooctyne provide the corresponding fully conjugated triazole product.