('13)C and ('15)N NMR chemical shift and spin-lattice relaxation data have been discussed for isomeric 2,4-pentanediamine and 1,3,5-triaminocyclohexane in chapter 1. At high pH, relaxation is consistent with hindered rotation of the NH(,2) group due in part to the formation of intramolecular hydrogen bonds. At low pH, relaxation is consistent with relatively unhindered rotation of the NH(,3)('+) group. Rotational jump rates and barriers are reported, as determined from the NT(,1) ratios between ('15)N and ('13)C nuclei. / Using Forrest's modified equation and proton coupling constants, the conformations of the two isomeric TACH were analyzed. The six-membered ring of the cis-trans isomer is flattened by 1,3 diaxial interactions between two amino substituents; in the cic-cis isomer the ring is puckered due to the non-bonded interaction between the equatorial amino groups and adjacent methylene protons. / The heteronuclear 2D NOE (HOESY) experiment was proposed in chapter 2, and proved to be a powerful technique for structural elucidation and conformation analysis for both ('13)C and ('31)P. It should be noted that this experiment gives information through space (dipolar interaction) rather than through bonds (J-coupling). For carbon-13, HOESY experiment provides information about dipolar interactions between quaternary carbons and nearby protons. A disadvantage of the HOESY experiment is that in order to detect the cross peaks of quaternary carbons a concentrated or isotopically enriched sample must be used. For phosphorus-31, a HOESY experiment was proposed to study solvent and intramolecular proton dipolar relaxation for the three phosphates in ATP. This technique should prove useful for the study of molecular conformation and solvent-solute interactions in a variety of chemical and biological systems. Since the other interesting nuclei can also be observed, the HOESY experiment is expected to have significant potential in studies of peptides (('15)N, ('13)C), metalloenzymes (M), and metabolic studies (('13)P, ('13)C). / Source: Dissertation Abstracts International, Volume: 45-06, Section: B, page: 1770. / Thesis (Ph.D.)--The Florida State University, 1984.

Time-dependent changes in absorption, emission, and/or photovoltage were measured for two chemical systems, organic electron donor-acceptor (EDA) complexes and inorganic metal oxides, in the picosecond and nanosecond time regimes. These changes were evaluated in terms of theories used to describe photoinduced charge separation. / Our investigations of several EDA complexes, which were composed of methyl- and halo-substituted benzenes and naphthalenes as donors (D) and tetracyanoethylene and chloranil acceptors (A), in solution involved ground-state absorption and steady-state emission analyses as well as time-dependent absorption and emission measurements. Photoexcitation into the charge-transfer bands of the EDA complexes resulted in the prompt formation of the contact radical ion pairs (CRIPs; $\rm D\sp{+\cdot},A\sp{-\cdot})$ whose lifetimes typically ranged $<$20 ps and 32 ns. / The interrelation of factors including reaction exoergicity, reorganization energies, electronic coupling between states, heavy-atom and isotopic substitution, local excited-state effects, and stoichiometry of the complex in the ground and excited states were elucidated with respect to the electron-transfer dynamics. The role of each of these factors in the photophysics of the EDA complex has been described in terms of theory for nonadiabatic electron transfer in the Marcus inverted region. / For the second type of chemical system, photovoltaic responses of polycrystalline wafers and oriented films of several metal oxides, including CuO, $\rm Cu\sb2O,\ Fe\sb3O\sb4,\ YBa\sb2Cu\sb3$O$\sb{7-x},$ and Bi$\sb2$Sr$\sb2$CaCu$\sb2$O$\sb{8+x}$, were measured in the absence of a transport current for a variety of excitation wavelengths, sample preparations, and environmental conditions. The largest responses were exhibited by YBa$\sb2$Cu$\sb3$O$\sb{7-x}$ wafers and films. For example, in response to irradiation with a 10-ns, 532-nm, 40-mJ laser pulse, polycrystalline wafers of YBa$\sb2$Cu$\sb3$O$\sb{7-x}$ exhibited room-temperature laser-induced transient photovoltages of $\sim$1 V maximum with a lifetime of $<$2.5 ns and an anisotropic dependence of the signal which scaled as the sine of the angle of incidence of the laser pulse and was nulled at normal incidence. The photovoltages were produced more efficiently with shorter wavelength light. In response to an $\sim$30-ps, 0.5-mJ, 532-nm laser pulse, the thin films of YBa$\sb2$Cu$\sb3$O$\sb{7-x}$ exhibited a peak voltage of $\sim$50 mV with a lifetime of $\sim$20 ns and a polarity which is reversed when the film is irradiated through the substrate rather than at the air/film interface. The mechanism for the laser-induced voltages in the films and wafers has yet to be established conclusively. / Source: Dissertation Abstracts International, Volume: 54-10, Section: B, page: 5123. / Major Professor: Edwin F. Hilinski. / Thesis (Ph.D.)--The Florida State University, 1993.

An analytical method for the in situ characterization of complex surfaces has been developed, validated and shown to be applicable in studying surfaces of importance in chromatography, geochemistry and catalysis. The method, "Heterogeneous Gas-Solid Chromatography (HGSC)," is rooted in present theories pertaining to chromatographic processes at finite concentration and pertaining to physical adsorption at heterogeneous surfaces. Fron HGSC, the complete distribution ("fingerprint") of adsorbate/adsorbent interaction energies, and hence the nature and quantity of surface active sites, can be inferred. / In the method's present state of development, the acidic, basic and dipolar sorptive characteristics of complex solid surfaces are determined by the use of solute probes capable of these specific interactions. From the energy distribution functions for each solute probe/surface combination, the energy required to form a monolayer has been calculated, and a surface polarity scale and surface selectivity triangle determined. The general acidity of a silica surface, the basicity and acidity of an alumina surface, the sorptive properties of a kaolinite surface, and the homogeneity of a graphitized carbon surface have all been monitored with the HGSC technique. Furthermore, applications in studying the sorptive properties of HPLC bonded phases, the sorptive properties of geochemically important soil organic matter and its subfractions, and the sorptive properties of thermally and chemically modified silica gels, have all been shown. This latter area is an example of the type of application in which the technique shows its greatest promise, the ability to quickly and inexpensively monitor the adsorptive properties of materials whose surfaces have been altered in some manner. / Source: Dissertation Abstracts International, Volume: 48-03, Section: B, page: 0729. / Thesis (Ph.D.)--The Florida State University, 1987.

This dissertation examines the effectiveness of several data processing treatments for quantitative analysis of mixtures in three areas of spectroscopy: fluorescence, absorption, and Raman. The data treatments considered are of two types, those that quantitate the analyte signal in the presence of a background signal and those that are used to quantitate all the constituents in the mixture. / The fluorescence study compares the results of several data treatments which utilize spectral shapes to distinguish analyte and nonanalyte signals. Two models are used for the comparison of data treatments. The first uses two components which are spectrally overlapped and the bandwidth for each of the two bands is markedly different. The second uses two components which are overlapped and the bandwidth for each band is similar. / The absorption section describes two experiments. The first experiment tests the effectiveness of several data treatments in extracting the signal of a minor constituent in the presence of a major constituent in a commercially available cold medicine. The second experiment compares the effectiveness of the data treatments on a mixture composed to two compounds with almost identical spectra. Results show that data treatments using all the spectral information are more effective in quantitating the components with similar overlapped spectra. The determination of the minor constituent was unsatisfactory with the equipment available. / The Raman spectroscopy section describes the quantitation of the active ingredients in a pharmaceutical preparation. The results of the data treatments on both solution and solid mixtures allow a comparison of the advantages and disadvantages for each data treatment and sample type. Raman spectroscopy was successful in quantitating the analyte signal in solid mixtures. / Source: Dissertation Abstracts International, Volume: 45-09, Section: B, page: 2896. / Thesis (Ph.D.)--The Florida State University, 1984.

The potential of Raman spectroscopy for the analysis of phenols in water has been investigated. A method of analysis based on the Raman technique would provide many advantages over other methods currently employed. It would be able to quantitate individual phenol derivatives directly in the water solution without separation. Due to the lack of sample pretreatment required, this method could serve as a basis of an automated field technique. / A group of nine compounds--phenol, o-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, 2-chloro-5-methylphenol, 2-chloro-4-nitrophenol, 4-nitrophenol, 3-nitrophenol, and 2-nitrophenol--was studied with the use of the 514.5 nanometer line of an argon ion laser. Detection limits range from 101 to 0.3 ppm, depending on the compound. Attention was given to the effects of source intensity, optical alignment, and background fluctuations on quantitative results. It was found that the use of an internal standard with each measurement made a significant improvement in the accuracy and precision. Two methods of quantitation, peak area measurement and cross-correlation were used. Results were somewhat better for cross-correlation. / A study was conducted to determine the effect of background fluorescence, as well as other interferences, on this method. It was concluded that most interferences found in natural waters could be eliminated with the use of cross-correlation and digital filtering techniques. Results were obtained from analysis of 2-chloro-4-nitrophenol in sea water and the simultaneous determination of three nitrophenols in a mixture. / The most important factor controlling sensitivity was the occurrence of resonance enhancement. Raman measurements of the nitrophenols with the 457.9 nm laser line resulted in detection limits of 190 to 30 ppb. Measurements were carried out with an ultraviolet laser source to examine qualitative and quantitative changes in the Raman spectra of the phenols as the condition of resonance enhancement is approached. These results were used to predict the detection limits which could be obtained from resonance enhancement of all the phenol compounds. / Source: Dissertation Abstracts International, Volume: 45-11, Section: B, page: 3487. / Thesis (Ph.D.)--The Florida State University, 1984.

The chemistry of trifluorophosphine containing complexes is interesting because of the similar bonding properties of PF(,3) and CO. Both are capable of pi back-bonding with transition metals. A series of PF(,3) substituted compounds, M(PF(,3))(,x)(CO)(,6-x), where M = Cr, Mo and W and x = 0 to 4, were synthesized and separated in our laboratory. The analytical separation of these compounds was investigated and quantified by gas chromatography. Separation of each different compound, X, was achieved as well as separation of the geometrical isomers at x = 2 and 3. A series of investigations into the reaction chemistry of these compounds was conducted at different energy inputs. The thermally induced isomerization reactions of cis and trans-M(PF(,3))(,2)(CO)(,4) was quantitatively followed and all pertinent kinetic parameters calculated. The rates of reaction were found to be dependent on the steric interactions of the phosphine ligands and metal size. Equilibrium concentrations of the cis and trans isomers are proposed to be dependent on steric interactions as well as electronic considerations. The reaction chemistry of tungsten trifluorophosphine carbonyls following neutron capture was studied. Irradiations of these compounds in the condensed and gas phase were conducted, with and without excess ligand gas. Methods were developed to be able to detect the trace amounts of scrambled products. A mechanism is proposed to account for the differing chemistries of PF(,3) and CO in this energy regime. / Source: Dissertation Abstracts International, Volume: 45-11, Section: B, page: 3486. / Thesis (Ph.D.)--The Florida State University, 1985.

A new interactive spectral data processing system was developed. While this system was built for FT-NMR applications, it is in no way limited to NMR. Powerful general purpose processing algorithms have been designed to provide users a high degree of flexibility and control over spectral data analysis. For example, users can choose the level of control to be exercised over a computation (manual, semi-manual, automatic). The system was designed to be run under a general purpose operating system which provides a spooled output and user security. Power and flexibility are also attained by the use of FORTRAN code in a highly modular configuration. New features are readily added with a minimum of effort. / Spectral data sets are stored in 32-bit floating point format and can consist of up to 16,384 complex points. The limitation of 16-bit CPU architecture necessitated the implementation of virtual data arrays to accomodate large data sets. Two virtual array manipulation techniques were developed: transparent and explicit. The transparent mechanism is easier to use but is at least an order of magnitude slower than the explicit mechanism. Comparisons of the mechanisms for a Fast Fourier Transform algorithm indicate that the transparent mechanism is inadequate for large data sets. / Quantitative ('13)C NMR techniques were developed and verified. Improvements in precision were obtained by the use of sophisticated integration software. Algorithms were developed to characterize and correct baseline distortions, define integration limits and correct for experimental effects. A factor of three increase in integral precision over standard methods is demonstrated. / Source: Dissertation Abstracts International, Volume: 42-01, Section: B, page: 0193. / Thesis (Ph.D.)--The Florida State University, 1981.

Traditional approaches to the computerization of laboratory instrumentation result in a one-to-one correspondence between computer and instrument. This becomes ineffective in a multiple instrument laboratory. An alternative approach is one in which each instrument has a dedicated data acquisition and control computer, with several such computers linked through a laboratory data network to a centralized data management computer. The development of such an approach is the subject of this dissertation. The problem is first defined in the context of a Nuclear Magnetic Resonance (NMR) laboratory, followed by a brief history of computers and a discussion of the ways in which computers have been applied in NMR. / After this, an introduction to the concepts essential to computer networking is presented, continuing with a discussion of the development of a local area network that utilizes industry-standard IEEE-488 protocols and incorporates differential line transmission for long-distance error-free operation. A Z80 microcomputer-based network interface is described which facilitates the easy connection of virtually any host computer to the network. Specific circuitry is also presented to interfaces S-100 (IEEE-696) microcomputers to the network. / Following discussion of the laboratory data network, the dissertation provides discussion of a microcomputer which was designed to operate as a stand-alone data acquisition and experimental control system, as well as a node in the network discussed earlier. This microcomputer utilizes several Z80 microprocessors and is based on S-100 circuit cards. Operator interaction is handled via a keyboard and a high resolution video graphics monitor. All software is based in Read Only Memory, providing a low-cost stand-alone system for a variety of laboratory applications. All data acquisition and experimental control is performed with sophisticated custom-built circuitry. / The remainder of the dissertation concentrates on the development of the custom circuits for data acquisition and experimental control. A subsystem is discussed that allows the interfacing of the host microcomputer to as many as 255 independent control processors via a single twisted-pair cable: useful in low-speed control and monitoring applications. A second subsystem handles data collection and time-critical instrument control. This subsystem, called the DAS, or Data Acquisition Subsystem, is based on modular design approaches, and consists of from two to five S-100 circuit cards. A minimal system is one Analog to Digital Converter card and a Signal Averager card. The AD circuit has on-board controls for analog gain, low-pass filtering, and digital resolution. The Signal Averager has three on-board counters to provide all of the control and timing signals for data collection. A hardware averager is also provided to allow the coaddition of repetitive signals. The Signal Averager is designed to support an optional Direct Memory Access Sequencer for high-speed signal averaging. A second AD card can be added to this subsystem, providing simultaneous two-channel data collection. The DAS optionally includes a Programmable Timer/Pulse Controller circuit which executes sophisticated timing programs of up to 16 steps with 50 nanosecond time resolution and maximum step length in excess of 15 hours. Precise experimental control is obtained through any of 24 programmable outputs that can be activated on any step. / Examples of the use of this system in NMR data collection are included. / Source: Dissertation Abstracts International, Volume: 42-06, Section: B, page: 2359. / Thesis (Ph.D.)--The Florida State University, 1981.

Source: Dissertation Abstracts International, Volume: 41-09, Section: B, page: 3434. / Thesis (Ph.D.)--The Florida State University, 1980.

This work deals with the quantitative use of Raman and resonance Raman spectroscopies. The types of difficulties that occur when using these spectroscopies are due to the many factors that affect Raman signals. In Chapter I, the general principles of Raman spectroscopy are discussed which include a description of the instrumentation, a comparison to IR spectroscopy, and a brief overview of the factors that affect the Raman signal. / The determination of azo dyes by resonance-enhanced Raman spectroscopy discussed in Chapter II describes the use of an internal standard to correct the Raman signal for fluctuations in excitation radiation power, optical alignment, and absorbance. Also, the use of frequency exclusion in the Fourier domain and data domain truncation to exclude fluorescence from the Raman signal will be discussed. Limits of detection in the parts-per-billion range are reported due to the resonance enhancement effect. / The use of Raman spectroscopy to detect and determine the concentration of minor components in a nominally pure solid is given in Chapter III. Background removal is accomplished through the use of an abscissa correction. Cross-correlation and least-squares fitting are used for quantitation to obtain limits of detection near 0.1%. Simulations are used to demonstrate how an iterative least-squares fitting program can be used to detect previously unknown impurities. / The effect of absorbance of the incident and scattered radiation on the Raman signal is discussed in Chapter IV. A correction set is derived that is based on an earlier work, but now includes a correction for the collection efficiency of the collecting optics and allows the user to apply the actual physical dimension of the path length. / In Chapter V, the use of a KrF excimer laser as the exciting source in a UV resonance Raman system is discussed. The generation of new lines in the UV by stimulated Raman scattering is described. Also, the problem of saturation and techniques to avoid its effects are discussed. / Source: Dissertation Abstracts International, Volume: 49-12, Section: B, page: 5269. / Major Professor: T. J. Vickers. / Thesis (Ph.D.)--The Florida State University, 1988.