Due to the endangerment of the June sucker (Chasmistes liorus), the lower two miles of Hobble Creek, Utah has been the focus of several restoration efforts. The portion of the creek between Interstate 15 and Utah Lake has been moved into a more "natural" channel and efforts are now being made to expand restoration to the east side of the freeway. This thesis reports on three different parts of a sedimentological analysis performed on Hobble Creek. The first part is a data set that contains information about the particle size distribution on the bed of Hobble Creek between 400 W and Interstate 15 in Springville, Utah. Particle size distributions were obtained for eleven sub-reaches within the study section. Particle size parameters such as D50 were observed to decrease from an average of 72 mm to 24 mm downstream from the 1650 W crossing and Packard Dam. Streambed armoring was observed along most of the reach. This data set can be used as input for PHABSIM software to determine the location and availability of existing spawning material for June sucker during a range of flows. The second part of this thesis compares predictions from four bed-load transport models to bed-load transport data measured on Hobble Creek. In general, the Meyer-Peter, Muller and Bathurst models overpredicted sediment transport by several orders of magnitude while the Rosgen and Wilcock methods (both calibrated models) were fairly accurate. Design channel dimensions resulting from the bed-load transport predictions diverged as a function of discharge. Once validated, the models developed in this section can be used by design engineers to better understand sediment transport on Hobble Creek. The models may also be applied to other Utah Lake tributaries. The third section of the thesis introduces a detailed survey data set that covers the Hobble Creek floodplain on the shifted section between Interstate 15 and Utah Lake with an approximate 10 foot resolution grid. Water surface elevations at two flows, along with invert, fence, saddles, and other points, are labeled in the survey. A comparison with a survey completed last year did not reveal any significant lateral changes caused by the 2010 spring runoff. Due to the potential importance of the side ponds to June sucker survival, this data set can be used to monitor sedimentation in the side ponds. It may also be used in a GSSHA model to determine the magnitude of flow that is required before each side pond will be connected to the main channel.

Cerium oxide has been used extensively for various applications over the past two decades. The use of cerium oxide nanoparticles is beneficial in present applications and can open avenues for future applications. The present study utilizes the microemulsion technique to synthesize uniformly distributed cerium oxide nanoparticles. The same technique was also used to synthesize cerium oxide nanoparticles doped with trivalent elements (La and Nd). The fundamental study of cerium oxide nanoparticles identified variations in properties as a function of particle size and also due to doping with trivalent elements (La and Nd). It was found that the lattice parameter of cerium oxide nanoparticles increases with decrease in particle size. Also Raman allowed mode shift to lower energies and the peak at 464 cm-1 becomes broader and asymmetric. The size dependent changes in cerium oxide were correlated to increase in oxygen vacancy concentration in the cerium oxide lattice. The doping of cerium oxide nanoparticles with trivalent elements introduces more oxygen vacancies and expands the cerium oxide lattice further (in addition to the lattice expansion due to the size effect). The lattice expansion is greater for La-doped cerium oxide nanoparticles compared to Nd-doping due to the larger ionic radius of La compared to Nd, the lattice expansion is directly proportional to the dopant concentration. The synthesized cerium oxide nanoparticles were used to develop an electrochemical biosensor of hydrogen peroxide (H2O2). The sensor was useful to detect H2O2 concentrations as low as 1µM in water. Also the preliminary testing of the sensor on tomato stem and leaf extracts indicated that the sensor can be used in practical applications such as plant physiological studies etc. The nanomolar concentrations of cerium oxide nanoparticles were also found to be useful in decreasing ROS (reactive oxygen species) mediated cellular damages in various in vitro cell cultures. Cerium oxide nanoparticles reduced the cellular damages to the normal breast epithelial cell line (CRL 8798) induced by X-rays and to the Keratinocyte cell line induced by UV irradiation. Cerium oxide nanoparticles were also found to be neuroprotective to adult rat spinal cord and retinal neurons. We propose that cerium oxide nanoparticles act as free radical scavenger (via redox reactions on its surface) to decrease the ROS induced cellular damages. Additionally, UV-visible spectroscopic studies indicated that cerium oxide nanoparticles possess auto-regenerative property by switching its oxidation state between Ce3+ and Ce4+. The auto-regenerative antioxidant property of these nanoparticles appears to be a key component in all the biological applications discussed in the present study.

Yes / This paper aims to evaluate the influence of surface area and amount of nano silica (NS) on the performance of concrete with different water/binder (w/b) ratios. For this purpose, 63 different mixes were produced using three NS having three differentsurface areas (52, 250 and 500 m2/g) and w/b ratios (0.4, 0.5 and 0.6). Compressive strengths , workability, water absorption and the microstrcture of concrete mixtures were measured and analysed. and the optimum ratio for each type was determined. The results indicated that the performance of NS particles in concrete is significantly dependent on its amount and surface area as well as w/b ratio. As the w/b ratio increased, a better performance was observed for all types of NS used, whilst NS having 250m2/g surface area was found to be the most effective. The optimum amount of NS ranged from 2 to 5%, depending on NS surface area. / The full-text of this article will be released for public view at the end of the publisher embargo on 15 May 2020.

In this study a sample of particles in a size region of 0.05-10 μm were run through a centrifugation process with the ambition to make it monodisperse. The product requirements were stated as follows, particles within the size range of 2 to 3.8 μm should be isolated and separated from the sample with a D90/D10 < 1.4 where the D90/D50/D10 values should be approximately 3.8 μm/2.5 μm/2 μm. It was found that two layers of sucrose with a 50/50 volume distribution of 45w% sucrose solution and 60w% sucrose solution respectively, was the most efficient density gradient arrangement for separation of this particular sample. The optimal time and RPM combination was found to be 5 min 3000 RPM with a fast acceleration and slower deceleration, ratio 9:6. Two centrifugation rounds on the same sample improved D90/D10 drastically. The effect of centrifugation rounds on D90/D10 was not investigated further than 3 rounds, however this would be a good starting point for further studies. The upscaled test runs indicated a positive result, i.e. the yields with respect to both mass and purity were reproducible. It is worth mentioning that the upscale was only in the volume, sample load volume and surface area factors. The gradient height or particle travel distance remained the same.

The aim of this work is to study the in-vitro aerodynamic performance of a new inhaled theophylline formulation prepared by supercritical fluids technique. For the analysis of the output from the in-vitro tests (and further in-vivo tests) a new, fast, sensitive high performance liquid chromatographic (HPLC) method was developed and validated for the determination of theophylline and other related derivatives in aqueous and urine samples using new packing materials (monolithic columns). These columns achieve efficient separation under lower backpressure and shorter time comparing to other traditionally or newly introduced C18 columns. Solution enhanced dispersion by supercritical fluid (SEDS) process has been applied for the production of anhydrous theophylline as pure crystals in the range 2-5 ¿m to be used as new inhaled dry powder formulation for asthma. Fifteen theophylline samples have been prepared under different experimental conditions. The drug produced by this method has been subject to a number of solid-phase analytical procedures designed to establish the crystal structure [X-ray powder diffraction (XRPD)], the structure and conformation [(FTIR), Fourier-transform Raman spectroscopy (FT-Raman)], and the morphology and particle size [scanning electron microscope (SEM)]. While, thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC) have been used to monitor any phase transition or polymorphic changes after processing. All these analytical techniques gave a satisfactory indication of the solid-state chemistry of the processed particles and assess the development of new inhalation product. The performance of inhaled SEDS theophylline with or without a carrier was evaluated using the developed HPLC method. Three samples having different particle sizes were selected out of the prepared powders by SEDS technique to be tested. The dose sampling unit and the Anderson Cascade Impactor were used to determine the in-vitro emitted dose and the deposition profiles of SEDS samples, respectively. The effect of different inhalation flows was studied using two different flows 28.3, and 60 L min-1 with 4 L inhalation volume. Different DPI devices were investigated in this study; Easyhaler® and Spinhaler®. The particle size has an important effect on the aerodynamic behaviour and deposition profile of inhaled drug, the smaller the particles the greater the total lung deposition. The presence of a carrier improves the respirable fraction for all the tested formulations. / Egyptian Ministry of Higher Education

The Sultanate of Oman is a rapidly modernizing country with a significant length of its coastline slated for development. Much of the coastline is still in its natural state and basic studies describing the sedimentary systems need to be conducted in order to plan effectively for their sustainable development and to monitor changes in them with time. For such purposes, sediment samples (surface and sub-surface), elevation data, and serial sediment cores were collected at Sur Lagoon during three field seasons. The research objectives, procedures, results, and analyses for Sur lagoon are presented in three chapters. The first chapter compares textural facies, identified on the basis of particle-size distribution (PSD) of surface sediments from Sur Lagoon and evaluated using multi-variate cluster analysis, for their value in recognizing modem sedimentary environments. Clustering the full PSD size spectrum (0.0375- 1888 μm) shows that facies identification is possible is closely tied to surface elevation, particle-size decreasing with increasing elevation above mean sea level. This analytical technique should be tested under different conditions to assess further its utility. The second chapter discusses the taphonomically distinct and laterally extensive (> 1 km2) bivalve shell bed deposited by a tsunami on November 28th, 1945. Taphonomic characteristics of this unit are compared to those of the shell-rich tsunamite from Caesarea, Israel, and resulted in the identification of three generic, tsunamigenic-specific traits in shell beds: 1) thickly bedded and laterally extensive shell deposit, 2) presence of allochthonous articulated bivalves not in life position, and 3) extensive angular fragmentation. When these three traits are found together, a tsunamigenic origin should be considered for the shell bed. The third chapter analyzes the PSD of the tsunamite in eight sediment cores for digested and undigested samples. Cluster analysis of the PSD extended the upper or lower tsunamite contacts in four cores, but in general, the tsunamite thickness is consistent with the previously identified shell beds (Chapter 3). The tsunamigenic processes that resulted in the deposition of the shell bed were complex, and deposition occurred during run-up, flooding, and backwash stages of the tsunami, incorporating marine, lagoonal, and terrestrial (wadi) sediment into the tsunamite. The results of this study provide baseline sedimentological data for an understudied region of the world. New applications of cluster analysis of PSD and taphonomic analysis have the potential to identify previously unknown tsunamites in the geological record, and lithological facies using textural analysis. / Thesis / Doctor of Philosophy (PhD)

Starter feed particle size (FPS) is typically small (~1200 µm) due to bird beak capacity (BC). Recent research has found that chicks can consume a larger FPS than previously thought; however, preferred FPS and its relationship with BC has not been established. Experiment 1 was conducted to determine the effect of breeder flock age (BFA) and feeding strategy (FS) on 0-14 d performance, BC and FPS preference. These data found that BC was dependent upon BFA and FPS consumed was dependent upon FS. Also, chicks could consume increased FPS without impacting starter performance; thus Experiment 2 was conducted to determine the effects of BFA and Starter FS on carryover performance (0-61 d), BC and processing metrics. Significant BFA differences occurred, though no FS carryover impact occurred for the measured variables. Overall, these data suggest that chicks can consume a FPS of ~2600 µm without negatively affecting starter or carryover performance.

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