In this study, it was experimentally proved, for the first time, that it is possible to predict the frequency of electromagnetic radiation that can modulate activity of proteins and more specifically activity of enzymes. The prediction was obtained using the computational model so called the Resonant Recognition Model (RRM). The model was tested here experimentally using the reaction catalysed with the enzyme l-lactate dehydrogenase (LDH). The RRM model was applied to the group of the enzymes belonging to the sub-subclass EC 1.1.1.27 i.e. l-lactate dehydrogenase. The wavelengths of the electro magnetic radiation calculated by the RRM and proposed to alternate activity of l-lactate dehydrogenate were identified at =620 25 nm and =840 25 nm. Enzyme activity was then measured after the exposure to the low-intensity, electromagnetic radiation (EMR) within the proposed EMR range [560-860 nm]. The experimental results have indeed shown that there is a significant increase in the activity of LDH only after irradiation within the range of the frequencies predicted by the RRM: 596nm (12%; P less than 0.001) and 829 nm (11.8%, P less than 0.001). These results prove successfully that activity of proteins and more specifically enzymes could be modified by EMR radiation of specific frequencies and even more that RRM computational model can successfully predict these frequencies.

Rare earths and copper systems were studied using X-ray absorption spectroscopy (XAS) and resonant inelastic X-ray scattering (RIXS). The use of monochromased synchrotron radiation and improved energy resolution for RIXS made possible to obtain valuable information on the electronic structure in 4f, 5f and 3d systems. Experimental results for rare-earths (Ho, Gd, Cm,U, Np, Pu) were analyzed by atomic multiplet theory based on the Hartree-Fock calculations. The inelastic scattering structures in RIXS spectra at 5d edge of actinides found to be sensitive to actinide oxidation states in different systems. Comparison of experimental and calculated Cm 5d RIXS spectra gave direct information about valency of the 248-curium isotope in oxide. Scientific understanding of processes that control chemical changes of radioactive species from spent fuel is improved by studying interactions of actinide ions (U, Np, Pu) with corroded iron surfaces. RIXS measurements at the actinide 5d edge indicate the reduction of U(VI), Np (V) and Pu (VI) to U(IV), Np(IV) and Pu (IV) by presence of iron ions. This thesis is also addressed to the study of changes in the electronic structure of copper films during interaction with synthetic groundwater solutions. The surface modifications induced by chemical reactions of oxidized 100Å Cu films with Cl−, SO42− and HCO3– ions in aqueous solutions with various concentrations were studied in-situ using XAS. It was shown that the pH value, the concentration of Cl− ion and presence of HCO3– ion in the solutions strongly affect the speed of the corrosion reaction. The Cu 2p RIXS was used to distinguish between the species present on the copper surface while in contact with groundwater solution.

At the heart of the field of photonics is the control of the reflection and transmission of light. Plasmonics looks at this problem of control of electromagnetic radiation in the context of surface plasmon polaritons (SPP). SPPs are propagating electromagnetic modes localized at the interfaces between media with positive and negative permittivities. Their excitation can accompany the enhancement of transmission, reflection, or absorption of EM radiation. There are a number of ways to excite SPPs and this work looks at several geometries and analyzes the transmission and reflection characteristics using a numerical approach based on the finite element method.<p> The first method of excitation is by incident evanescent wave that was totally internally reflected from an earlier interface. It is shown that an evanescent wave can excite SPPs and create resonant transmisison. It is also found that high values of dissipation limit transmission and instead create resonant absorption. The second method involves the modulation of the negative permittivity of the plasma slab itself. Numerical results are compared to analytical ones and are in good agreement because harmonics of the solution above the first are negligible. An investigation of transmission through a plasma slab with a single thin diffraction grating placed nearby follows. Analytical and numerical calculations show that a single thin grating is sufficient to create transmission resonance. It is found that for large values of diffraction grating modulation parameter, higher harmonics, usually not accounted for in analytical solutions, results in discrepancies between analytical and numerical results. The next geometry considered is of a plasma layer with only part of it having modulated permittivity. The presence of modulation of only part of the plasma layer is shown to create transmission and reflection resonances. By tailoring parameters of the system, it is shown how the resonant frequencies can be shifted. The final geometry considers a copper grating beside a plasma and transmission of a radio frequency wave. Even though the copper used here in this simulation is very absorbing, there are ranges of frequencies when transmission or reflection are enhanced.

Optical transition energies are widely used for providing experimental insight into the electronic band structure of single-wall carbon nanotubes (SWCNTs). While the first and second optical transitions in semiconducting carbon nanotubes have already been heavily studied, due to experimental difficulties in accessing the relevant excitation energy region, little is known about higher lying transitions. Here, I present measurements of the third and fourth optical transitions of small-diameter (0.7-1.2 nm), semiconducting single-wall carbon nanotubes via resonant Raman spectroscopy in the visible deep blue region (415-465 nm) and photoluminescence excitation spectroscopy in the ultraviolet and visible blue optical regions (280-488 nm). Diameter-dependent Raman radial breathing mode features, as well as resonant energy excitation maxima determined by Raman and photoluminescence measurements, are assigned to specific (n,m) nanotube species. The Raman intensity within a given 2n+m branch is found to increase with decreasing chiral angle, consistent with similar measurements for lower order optical states. Additionally, increased excitation line widths and weaker Raman intensities are observed as higher lying transitions are accessed for a given nanotube, in agreement with previous Raman measurements. Chiefly, a scaling law analysis that removes the chiral-angle-dependent contribution to the optical transition energy indicates that the third and fourth transition energies exhibit a significant deviation from the energy trend line observed for the first and second optical transitions, when the transition energies are plotted as a function of nanotube diameter. This deviation can be understood in the context of a change in the competition between exchange and excitonic correction terms. Furthermore, for semiconducting SWCNTs with diameters less than 0.9 nm, an additional deviation is observed that is interpreted as the first observation of crossing-over of the third and fourth transition energy trend lines for a given 2n+m branch and a chirality dependence in the many-body excitonic effects that becomes significant at high nanotube curvatures.

Dynamic properties of soils (shear stiffness and damping ratio) are critical for the design of structures subjected to vibrations. The dynamic properties of a benchmark standardized laboratory sand (Ottawa silica sand) were evaluated with two different resonant column devices, utilising software with different analytical approaches for the evaluation of soil properties. The dynamic properties (shear modulus and damping ratio) are evaluated as a function of the shear strain level. The results are compared to evaluate the effect of the type of equipment and the form of the data analysis on the measured dynamic properties of the samples. The results are discussed in light of the applicability of the procedures in practice, the ease of the testing methods, and the errors they introduced into analysis and design. In general, the shear wave velocities obtained from the two different devices are in good agreement. However, the damping ratios they give show considerable differences as strains increase. Dynamic properties are typically measured by curve fitting of the transfer function between the excitation and the response using the resonant column device. However, the force function generated by sinusoidal sweep or random noise excitations induce different shear strain levels at different frequencies. Consequently, the shape of the measured transfer function is distorted and differs from the theoretical transfer function for an equivalent single-degree-of-freedom system. The difference between the measured and theoretical transfer functions as well as the bias in the computed dynamic properties becomes more pronounced with the increase in shear strain. This study presents a new methodology for the evaluation of dynamic properties from an equivalent constant-strain transfer function. The soil specimen is excited simultaneously using a sinusoidal excitation (carrier signal) at the required strain level and a small amplitude, narrow band random noise. The strain level induced by the fixed sine is shown to control the resonant frequency of the specimen; whereas the random noise introduces the required frequency bandwidth to determine the transfer function and hence the dynamic properties at a constant strain level. The new methodology also shows a good potential for the evaluation of frequency effects on the dynamic properties of soils in resonant column testing.

At the heart of the field of photonics is the control of the reflection and transmission of light. Plasmonics looks at this problem of control of electromagnetic radiation in the context of surface plasmon polaritons (SPP). SPPs are propagating electromagnetic modes localized at the interfaces between media with positive and negative permittivities. Their excitation can accompany the enhancement of transmission, reflection, or absorption of EM radiation. There are a number of ways to excite SPPs and this work looks at several geometries and analyzes the transmission and reflection characteristics using a numerical approach based on the finite element method.<p> The first method of excitation is by incident evanescent wave that was totally internally reflected from an earlier interface. It is shown that an evanescent wave can excite SPPs and create resonant transmisison. It is also found that high values of dissipation limit transmission and instead create resonant absorption. The second method involves the modulation of the negative permittivity of the plasma slab itself. Numerical results are compared to analytical ones and are in good agreement because harmonics of the solution above the first are negligible. An investigation of transmission through a plasma slab with a single thin diffraction grating placed nearby follows. Analytical and numerical calculations show that a single thin grating is sufficient to create transmission resonance. It is found that for large values of diffraction grating modulation parameter, higher harmonics, usually not accounted for in analytical solutions, results in discrepancies between analytical and numerical results. The next geometry considered is of a plasma layer with only part of it having modulated permittivity. The presence of modulation of only part of the plasma layer is shown to create transmission and reflection resonances. By tailoring parameters of the system, it is shown how the resonant frequencies can be shifted. The final geometry considers a copper grating beside a plasma and transmission of a radio frequency wave. Even though the copper used here in this simulation is very absorbing, there are ranges of frequencies when transmission or reflection are enhanced.

This dissertation focuses on the development of integrated circuits that employ InAs quantum well electronic devices. There are two InAs quantum well electronic devices studied in this work, the first being the pseudomorphic InAs/In₀.₅₃Ga₀.₄₇As/AlAs resonant tunneling diode (RTD) grown on an InP substrate, and the second being the InAs/AlSb HEMT. Because of there is no semi-insulating substrate near the InAs lattice constant of 6.06 Å this work develops monolithic and hybrid integration methods to realize integrated circuits. For the case of hybrid RTD circuits, a thin-film integration method was developed to integrate InAs/In₀.₅₃Ga₀.₄₇As/AlAs RTDs to prefabricated CMOS circuits, and this technique was employed to demonstrate a novel RTD-CMOS comparator. To achieve higher speed circuit operation, a next-generation RTD fabrication process was developed to minimize the parasitic capacitance associated with the thin-film hybridization process. This improved fabrication process is detailed and yield and uniformity analysis is included. Similar InP-based tunnel diodes can be integrated with InP-based HEMTs in monolithic RTD-HEMT integrated circuits, and in this work elementary microwave circuit components were characterized that co-integrate InP-based tunnel diodes with HEMTs. In the case of the InAs/AlSb HEMT, the monolithic approach grows the HEMT on a metamorphic buffer on a GaAs substrate. The semiconductor material and process development of the InAs/AlSb HEMT MMIC technology is described. The remarkable microwave and RF noise properties of the InAs/AlSb HEMT were characterized and analyzed, with special attention given to the strong effects of impact ionization in the narrow bandgap InAs channel. Results showed the extent to which impact ionization affects the small-signal gain and noise figure of the HEMT, and that these effects become less prevalent as the frequency of operation increases.

Two problems in computational wave dynamics are considered: (i) the use of Klemp-Wilhelmson time splitting at large scales and (ii) analysis of wave-wave instabilities in nonhydrostatic and rotating mountain waves. The use of Klemp-Wilhelmson (KW) time splitting for large-scale and global modeling is assessed through a series of von Neumann accuracy and stability analyses. Two variations of the KW splitting are evaluated in particular: the original acousticmode splitting of Klemp and Wilhelmson (KW78) and a modified splitting due to Skamarock and Klemp (SK92) in which the buoyancy and vertical stratification terms are treated as fast-mode terms. The large-scale cases of interest are the problem of Rossby wave propagation on a resting background state and the classic baroclinic Eady problem. The results show that the original KW78 splitting is surprisingly inaccurate when applied to large-scale wave modes. The source of this inaccuracy is traced to the splitting of the hydrostatic balance terms between the small and large time steps. The errors in the KW78 splitting are shown to be largely absent from the SK92 scheme. Resonant wave-wave instability in rotating mountain waves is examined using a linear stability analysis based on steady-state solutions for flow over an isolated ridge. The analysis is performed over a parameter space spanned by the mountain height (Nh/U) and the Rossby number (U/fL). Steady solutions are found using a newly developed solver based on a nonlinear Newton iteration. Results from the steady solver show that the critical heights for wave overturning are smallest for the hydrostatic case and generally increase in the rotating wave regime. Results of the stability analyses show that the wave-wave instability exists at mountain heights even below the critical overturning values. The most unstable cases are found in the nonrotating regime while the range of unstable mountain heights between initial onset and critical overturning is largest for intermediate Rossby number.

ABSTRACT The effects of ultrasonic irradiation at different frequencies, i.e. 0.25, 0.5, 1, and 5 MHz, on the biological reaction of the single cell creature have been investigated. When multi-cell creature is exposed to ultrasound, this reaction will lead the biological effect becomes complex. Therefore, in this dissertation, a single cell creature is chosen to study the biological effects induced by ultrasound exposure. The paramecium, which possesses many features typical of higher-order animal cells, was considered as an appropriate choice for this study. The ability shown by ultrasound in promoting and/or accelerating many reactions has been shown to be a useful field. The resonant frequency of paramecium by using the ultrasound irradiation is an important parameter in this research. All other parameters being kept constant, it has been ascertained that an appropriate frequency value of ultrasound can be selected, capable of driving a biological reaction to its suitable yield. The oscillation of the cells in response to the ultrasound radiation is simulated using Rayleigh-Plesset¡¦s bubble activation theory. The resonant frequency of the unicellular creature is then calculated. In the experiment, the resonant (0.5 and 1 MHz) and non-resonant (0.25 and 5 MHz) frequencies were employed. The theoretical resonant frequency of the paramecium vacuole is among 0.5013~1.2703 MHz. In this thesis, the experiment included two different series. The exposure intensity is the major subject of the first experimental series to study the bioeffect of ultrasound. The waveform was set to the tone pulse mode, pulsing 1:1. The exposure duration was continued and maintained 5 minutes. For a given frequency, exposures of the paramecium were made over a range of intensities spanning 0 to 1.7 mW/cm2. The second experimental series was focused on the exposure duration of the ultrasound. The transducers were operating in a pulsed mode with two duty cycles of 1:1 and 1:9. All insonated samples were exposed to ultrasound with a spatial peak temporal peak intensity (SPTP) of 0.127 mW/cm2. The total ¡§with signal¡¨ time was about 6 minutes in each trial. In addition, the control samples and the treated samples would be re-incubated up to the 96 hr. When the 1 MHz frequency of ultrasound was irradiated in the samples, there was about 24% inhibition rate and 30% enhancement rate in the first experimental series. The 0.5 MHz frequency of ultrasound, which approaches to the resonant frequency range, also appeared the inhibitive and beneficial effect. In the second experimental series, the relative growth number was about 32.4% higher than that of unexposed sample. The inhibition or enhancement growth conditions did not appear apparently during irradiation the non-resonant frequency of ultrasound. Moreover, experimental evidence suggests that the sustaining growth effect can be expected, when the irradiation time is divided into parts.

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