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数学 & 物理 & 化学 & 力学 : 学术学位
The standard model (SM) of elementary particles has been established for more than 30 years and tested by a large number of experiments. However, because of the naturalness problem of the electroweak symmetry breaking scale and a large number of unexplained parameters in SM, physicists have been loo
INVESTIGATIONS OF THE FISCHER-TROPSCH SYNTHESIS AND THE HYDROGENOLYSIS OF ALKANES (CATALYSIS, CARBON MONOXIDE, HETEROGENEOUS).
This dissertation is divided into two parts. The first part involves the mechanism of the Fischer-Tropsch synthesis, a heterogeneous catalytic reaction which synthesizes linear hydrocarbons from carbon monoxide and hydrogen. The second part involves an investigation of the mechanism of the hydrogeno
Self-organization of polymers in bulk, thin films, and solutions: Studies of semiflexible perfluorocyclobutyl polyaryl ethers and rigid rod dialkyl para-phenyleneethynylenes.
The structures and dynamics of two classes of polymers have been explored. The first class of polymers, containing an α-methylstilbene mesogenic group and a low interfacial energy perfluorocyclobutyl ring, forms lyotropic lamellar mesophases over a wide range of temperatures and molecular weig
Near-field photocurrent studies of temperature and polarization dependence in relaxed silicon germanium films on silicon substrates.
Near-field scanning optical microscopy (NSOM) is used to examine the local photoexcitation of carriers within fully relaxed SiGe films on Si substrates. Two NSOM techniques were applied to this problem and their results are presented. The still developing field of NSOM allows for the subdiffraction-
The chemistry of metal clusters is a fascinating and expanding area of research. During the last three decades, the study of metal clusters and in particular transition metal clusters has been the subject of numerous experimental and theoretical investigations. The desire to understand the frontier
A spectrometer was built to study Raman optical activity, using the coherent scattering technique known as optical heterodyne detected Raman-induced Kerr effect spectroscopy. Signals were generated with a combination of an excimer pumped dye laser and single mode krypton-ion laser. The detection sys
Studies toward the enantioselective total synthesis of the marine natural toxin pectenotoxin 2 are described. A successful approach to a fully functionalized precursor to the C(29)--C(40) FIG sector began with the establishment of a proper stereochemical relationship between the hydroxyl and methyl
Questions about the existence of integer solutions to Diophantine equations have interested mathematicians since antiquity. In the 1970s, the work of Davis, Matiyasevic and Robinson showed that no universal algorithm may exist which can test, all arbitrary Diophantine equation for integer solutions.
The study and characterization of high power explosives has become an important research field due to the constant use of these kinds of materials by terrorists. In order to develop an efficient explosive detection system, the explosives must be fully characterized. One of the techniques being explo
New chromatographic materials for liquid chromatography and ultrahigh-pressure liquid chromatography.
Typically, silica particles containing chemically bonded phases are used as the chromatographic material in high performance liquid chromatography (HPLC). As an alternative to these types of materials, we have explored the potential use of self-assembled monolayers on gold-coated silica particles un
Part I begins with an investigation of the alkyne metathesis process, particularly with regards to the catalyst's tolerance to different functional groups. The findings are taken into account as the same simple catalyst system is used to form novel macrocycles (chapter 2) and novel alkyne-bridged co
This dissertation involves the design, fabrication and characterization of wide band gap semiconductor optical waveguide devices. Prism coupling was used as the primary characterization method to obtain design parameters of the refractive index and propagation loss of the wide band gap semiconductor
Phorboxazoles A and B were isolated from the extracts of the marine sponge
Phorbas sp off the coast of western Australia. In 1995, after extensive NMR, derivatization, degradation and correlation studies, they unveiled an unprecedented chemotype. Preliminary biological data against
We consider the problem of optimal switching with finite horizon. This special case of stochastic impulse control naturally arises during analysis of operational flexibility of exotic energy derivatives. The current practice for such problems relies on Markov decision processes that have poor dimens
The focus of this work is the employment of thin films on surfaces to create novel optical, mechanical, or chemical properties. In the case of novel optical properties, the successful production of a thin solid film of potassium niobate is described as well as the usefulness of nonlinear optical app
The main results of this thesis can be divided into two parts. In the first part, we consider the isomorphism problem for enveloping algebras. Let L be a Lie algebra with universal enveloping algebra U( L). Given another Lie algebra H with the property that U(L) ≅ U( H) as algebras, the isomor
Coherent control of light and matter is a major tool in current atomic physics and physical chemistry research. Technological advances in ultrafast laser pulse shaping allow control over the dynamics of molecular systems on sub-picosecond timescales. This thesis demonstrates feedback control over a
This study is designed to analyze the optional adoption of a standard e-mail application at a large Midwestern university. Explanations are proposed for the reasons initial results indicate both similarities and differences between the observed adoption behavior and that which Diffusion Theory (Roge
This thesis investigates two important topics in modern statistical mechanics. The first three chapters are devoted to the statistical mechanics of random surfaces. We present an analysis of extensive large-scale Monte Carlo simulations of Self-avoiding