Experiments were designed to study the effects of various intensities and durations of light during early development on meristic variation in kokanee and sockeye salmon (Oncorhynchus nerka), pink salmon (O. gorbuscha) and in rainbow trout (Salmo gairdneri). An experiment with sockeye was designed exclusively to test the period of fixation of vertebrae. Among the salmon species rates of hatching and yolk-sac absorption were fastest under the longer light durations and higher intensities. In sockeye and pink an increasing rate of yolk-sac absorption was correlated with increasing amount of light. In trout the rate of yolk-sac absorption showed the opposite results. Mortalities were high under all the experimental conditions. Although meristic variability observed was deemed to be phenotypic yet the affects of selective mortality could not be entirely excluded. Abnormalities in the vertebral column were prevalent in the ‘pre-urostylic' region. The occurrence of abnormal vertebrae was correlated with light only in sockeye. The activities of the pituitary and thyroid glands of trout showed a positive correlation with higher amounts of light. Sockeye scale counts, along the lateral line and on the oblique rows from the origin of dorsal and anal fins to lateral line, were lowest under conditions of higher light and longer durations. Fin ray numbers in all species were the lowest at high light intensities and longer durations. Vertebral counts were lowest at high light intensities and long durations in pink salmon and rainbow trout, but higher in sockeye. At lower light intensities and durations results were variable. Vertebral counts of sockeye increased with increasing light at temperatures of both 8°C and 12°C. Differences among lots at 8°C were significant but those among comparable lots at 12°C were not. The action of light on meristic variability was weak at the higher temperature. It was found in sockeye that vertebral numbers were not fixed before 142 D° and that the period of sensitivity was prolonged (142 D° to 300 D°). / Science, Faculty of / Zoology, Department of / Graduate

The electron density in a plasma jet has been determined as a function of position in the jet by measurements of the coherent scattering of laser light. The electron density profiles thus obtained are compared with profiles obtained from measurements of spectral line intensities. The results of these two diagnostic methods are seen to agree within experimental error. For the experiment described here, the scattering is from correlated motion of the electrons, and the scattered light spectrum has distinct electron satellites. It is shown that the width of these satellites, observed in earlier work by Chan and Nodwell (1966), may be accounted for by the electron density gradients in the plasma. This thesis gives a short review of techniques and relevant theory, with emphasis on experimental problems. A brief discussion of perturbation of the plasma by the laser light is also included. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

To calculate the emergent radiation field, a realistic atmospheric model and algorithm must be developed. The radiation field may be characterized by the emergent intensities of scattered light. This is possible only if the algorithm determines these intensities as dependent upon atmospheric and angular parameters.

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Dramatic increase of energy consumption and environmental problems invigorate the development of organic semi-conductive materials to substitute for the conventional inorganic materials in the application of photovoltaic and light-emitting devices. In view of the merits of low driving voltage, high power conversion efficiency, large-area fabrication of thin and light organic films as well as saturated emission, organic light-emitting diodes (OLEDs) have received much more consideration by scientists in the past two decades. And even out of laboratory, the OLEDs are popular among the commercial electronic products for solid-state displays and illumination. Generally, three primary RGB emitters, involving red (R), green (G) and blue (B), are footstones to achieve solid-state displays and illumination because the spectra by compositing RGB emissions match very well with the solar spectrum. Also, the combination of two complementary luminophors, blue and orange or yellow is an alternative approach to simulate the solar spectrum for white light illumination. Except for the full-color light-emitting materials for solid-state displays and illumination, near infrared (NIR) organics are of great importance for applications in information-secured devices, communications, biosensors, and phototherapy. To date, uncountable research works focusing on the emitters for full-color emissions have demonstrated their synthesis, photophysical properties and OLED application, which shows enough efficiency and stability to commercial utility. However, there are still three challenging issues which are needed to be handled urgently. Firstly, the lack of efficient deep blue emitters makes the external quantum efficiency (EQE) of deep blue OLEDs around 10% when the Commission Internationale de l'Éclairage (CIE) coordinates of y is smaller than 0.1. On the one hand it is difficult to achieve the deep blue emitters with extremely broad energy gap between the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO). On the other hand the triplet and frontier energy levels of the host, electron transporting layer (ETL) and hole transporting layer (HTL) in the device are required to well match with that of the emitters. Secondly, high energy in the emissive layer (EML) of deep blue OLEDs may degrade the materials used inside the EML, resulting in their short lifetimes. Thirdly, by comparison with other colors, the investigations of NIR emitters, such as their preparation, property study and device fabrications are sparse.;By harvesting both 25% singlet and 75% triplet excited states, iridium(III) [Ir(III)] complexes have been proven to be one of the best candidates to achieve highly efficient phosphorescent OLEDs (PHOLEDs) for solid-state displays and illumination. Herein, based on Ir(III) complexes, 18 phosphors were synthesized to achieve a widely tunable phosphorescence from deep blue to NIR. In this thesis, their synthesis were fully characterized by NMR spectroscopy, mass spectrometry and X-ray crystallography. Further investigations on the photophysical, electrochemical and thermal properties reveal that these phosphors have the possibility of device fabrication. And rational design of device architectures afford the OLEDs with high efficiencies.;Firstly, N-heterocyclic carbene ligands (CˆC:) were used to elevate the LUMO of phosphors (Ir1-Ir7), resulting in true and deep blue emission spanning from 420 to 450 nm. Secondly, the widely tunable phosphorescence from 470 to 614 nm was accomplished by using polyfluorinated 2-phenylpyridine (CˆN) derivatives as cyclometallated ligands of Ir(III) complexes (Ir10-Ir17). Interestingly, electron-withdrawing trifluoromethyl (CF3) group on the phenyl ring of CˆN-type ligands results in significantly red-shifted emissions of Ir(III) complexes, which distinguishes with the blue-shift effect of fluoride approach. Lastly, by comparison with the reported literature on NIR Ir(III) phosphors with extensive conjugation, the addition of slight conjugation but electron-withdrawing moieties onto the pyridyl ligands is a powerful and convenient avenue to tune the phosphorescence of Ir(III) phosphor into the NIR region, emitting at 729 nm.;Meanwhile, the deepest blue OLED made from Ir1 showed a peak EQE of 7.1% with CIE of (0.16, 0.11). And the best deep blue OLEDs made from Ir7 by using single and double electroluminescent (EL) units gave the highest EQE of 19.0% and 31.5% with CIE coordinates of (0.15, 0.19) and (0.15, 0.22), respectively. Such high efficiencies are comparable to and even better than the currently reported deep blue PHOLEDs. Also, the sky blue, green, yellow, orange, red and NIR PHOLEDs fabricated from Ir10, Ir13, Ir15, Ir16, Ir17 and Ir18 afforded the maximum EQE of 11.2%, 20.1%, 15.4%, 9.9%, 6.8% and 4.0%, respectively. By stacking RGB EML, the white PHOLED (PHWOLED) made by Ir1, Ir13 and Ir17 gave a peak EQE of 16.0% and CIE of (0.36, 0.47).;All in all, this thesis has successfully combined the materials synthesis and devices design to achieve efficient full-color and NIR PHOLEDs which are of great interest for solid-state displays and illumination. These works have a great significance in terms of the improvement of efficiency and stability of deep blue OLEDs as well as simplifying the synthesis methods to prepare highly efficient NIR Ir(III) phosphors.

A proposition for a theater in Roanoke, Virginia is the vehicle for the exploration of architectural ideas on space, form, materiality, and atmosphere. The thesis developed through a series of models and drawings that studied oppositions in mass, scale, transparency, opacity, and most importantly, light vs. dark and day vs. night. / Master of Architecture

In order to study the detailed spectral intensity distribution of light reflected from a solid-gas interface, the extinction theorem in optics is extended to include an absorbing medium and the thermal motion of the gas molecules near the interface. The theoretical spectral intensity distribution in the region of anomalous dispersion is found to be strongly modified compared to that predicted by existing theory. An important consequence of this theory in the line shapes of the reflected light is the possibility of using recently developed saturation spectroscopic techniques to study atoms and molecules near surfaces. In order to investigate the feasibility of these new techniques for obtaining solid-gas molecule interaction potentials, models of solid-gas interfaces were studied with and without interactions of the type 1/zP (p = 2,3,4), where z is the distance between gas molecules and solid surface. A marked difference in the line shapes of the reflected light among the possible interactions suggests that the forms of interaction at the interface can be measured using known techniques. Furthermore, the possibility of measuring the flow of gas near walls where currently available laser-Doppler anemometers can not spatially reach is investigated. It is shown that the shift and width of the numerically calculated line shape of the reflected light in our model flow is directly related to the mean and the fluctuating velocity fields respectively.

Indiana University-Purdue University Indianapolis (IUPUI) / Recently witnessed a great popularity of unobtrusive Visible Light Communication (VLC) using screen-camera channels. They overcomes the inherent drawbacks of traditional approaches based on coded images like bar codes. One popular unobtrusive method is the utilizing of alpha channel or color channels to encode bits into the pixel translucency or color intensity changes with over-the-shelf smart devices. Specifically, Uber-in-light proves to be an successful model encoding data into the color intensity changes that only requires over-the-shelf devices. However, Uber-in-light only exploit Multi Frequency Shift Keying (MFSK), which limits the overall throughput of the system since each data segment is only 3-digit long. Motivated by some previous works like Inframe++ or Uber-in-light, in this thesis, we proposes a new VLC model encoding data into color intensity changes on red and blue channels of video frames. Multi-Phase-Shift-Keying (MPSK) along with MFSK are used to match 4-digit and 5-digit long data segments to specific transmission frequencies and phases. To ensure the transmission accuracy, a modified correlation-based demodulation method and two learning-based methods using SVM and Random Forest are also developed.

Secondary structures may have to endure severe vibration amplitudes under the influence of the primary structures on which they are mounted. A series of numerical case studies are presented in this thesis to investigate the effectiveness of a passive vibration controller which combines a conventional tuned absorber with an impact damper, to attenuate the excessive vibration amplitudes of light secondary structures. In addition, experimental measurements are reported for some selective cases and comparisons are made with numerical predictions. This suggested configuration seems to suit ideally as an add-on enhancer for existing conventional absorbers. Most of the Results are presented for random white noise excitation, and a few representative transient vibration cases are also studied. / Thesis / Master of Engineering (ME)

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