Rock and debris avalanches result from sudden rock slope failure; they occur in a variety of materials and landscapes, and often have a catastrophic and lasting impact on the society, infrastructure, and landscape of the area. In order to fully understand these events, the factors leading to failure and those influencing the course of the event must be investigated. In recent years, increased attention has been given to numerous aspects of rock/debris avalanche emplacement: among these is the influence of runout path material on the behaviour of snow and ice avalanches, pyroclastic currents, debris flows, volcanic debris avalanches and non-volcanic rock avalanches. The fact that substrates are involved in rock avalanche emplacement has been known since Buss and Heim remarked on it in 1881, but few detailed studies on the effects of this involvement on avalanche emplacement exist. One popular hypothesis which has emerged is that the long runout of large rock avalanches can be explained by the basal friction reduction due to overrunning or failure of saturated substrate material. However, the present study shows that this is not the case. From analysis of nearly 400 rock and debris avalanche deposit descriptions it is evident that: (1) avalanches inevitably interact with their runout path material; (2) all large (> 10⁶ m³) rock and debris avalanche events have runout distances that exceed simple frictional model predictions regardless of type or degree of substrate interaction; (3) substrates only add complexities to the ‘long-runout’ avalanche events similar to topographic interference. The complexities resulting from substrate interaction include, for example, characteristic deposit surface features such as longitudinal ridges and flowbands, compressional faults and raised margins from rapid deceleration behind e.g. bulldozed substrates; shearing in a basal mixed zone and consequent changes in basal avalanche mechanical properties; volcanic edifice failure on weak underlying sediments with a change in volcano shape; transformation into more mobile debris flows through the entrainment of large quantities of water or water-bearing materials; and many others.

Rock and debris avalanches result from sudden rock slope failure; they occur in a variety of materials and landscapes, and often have a catastrophic and lasting impact on the society, infrastructure, and landscape of the area. In order to fully understand these events, the factors leading to failure and those influencing the course of the event must be investigated. In recent years, increased attention has been given to numerous aspects of rock/debris avalanche emplacement: among these is the influence of runout path material on the behaviour of snow and ice avalanches, pyroclastic currents, debris flows, volcanic debris avalanches and non-volcanic rock avalanches. The fact that substrates are involved in rock avalanche emplacement has been known since Buss and Heim remarked on it in 1881, but few detailed studies on the effects of this involvement on avalanche emplacement exist. One popular hypothesis which has emerged is that the long runout of large rock avalanches can be explained by the basal friction reduction due to overrunning or failure of saturated substrate material. However, the present study shows that this is not the case. From analysis of nearly 400 rock and debris avalanche deposit descriptions it is evident that: (1) avalanches inevitably interact with their runout path material; (2) all large (> 10⁶ m³) rock and debris avalanche events have runout distances that exceed simple frictional model predictions regardless of type or degree of substrate interaction; (3) substrates only add complexities to the ‘long-runout’ avalanche events similar to topographic interference. The complexities resulting from substrate interaction include, for example, characteristic deposit surface features such as longitudinal ridges and flowbands, compressional faults and raised margins from rapid deceleration behind e.g. bulldozed substrates; shearing in a basal mixed zone and consequent changes in basal avalanche mechanical properties; volcanic edifice failure on weak underlying sediments with a change in volcano shape; transformation into more mobile debris flows through the entrainment of large quantities of water or water-bearing materials; and many others.

Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 72-73). Also available on the World Wide Web.

The thesis is mainly divided into three parts. The first part will discuss about structures, manufacture, and design flow of embedded passives in organic and flexible substrates, and the results of measurement and electromagnetic (EM) simulation will be compared as well. Second part will discuss the theory and the process of establishing broadband model, and the broadband model will be compared to Pi model and EM simulation. In the third part, we will try to design embedded bandpass filters in organic substrate by the experience of establishing the library of embedded passives. Because of lacking of the fabrication of large capacitance devices in organic substrate, we design bandpass filters by using T type in order to limit the lump devices in the larger inductance and smaller capacitance. The final result of the filters are small in size and have high performance, thus they can be well applied to the RF system in chip (SIP) of wireless communication.

In this research, we used monomer 4,4¡¦¡¦¡¦¡¦-Difluore-3,3¡¦¡¦¡¦¡¦- bis(trifluoromethyl)-2¡¦¡¦,3¡¦¡¦,5¡¦¡¦,6¡¦¡¦-triphenyl and 4,4'-(9-Fluorenylidene) diphenol to fabricate the novel poly(arylene ether)s by the nucleophilic replacement reaction. We call this polymers P-44, and we use Mass and GPC to measure its molecular weight¡FThe molecular structures were investigated and confirmed by NMR and FT-IR. This polymer has high weightaverage molecular weight (Mw) about 5.67¡Ñ104 g/mol. We can realize from the measurement of thermal analysis that its thermal degradation temperature (Td) is 543¢XC, and its glass transition temperature (Tg) is 331¢XC. It shows this polymer: P-44 possesses great thermal stability. Besides, P-44 has not apparent crystallizing point (Tc) so we can adjust that P-44 crystalize hardly. We can know from above that P-44 can not only has good heat tolerance but also has high thermal stability so it can endure futher high tempaerature in the process of fabrication. After interpreting P-44 possesses these well properties, we want to know the properties that P-44 apply to the devices as flexible substrate. So, we fabricate P-44 to be film, and we measure the photoelectrical properties of P-44 film. From this we can observer if P-44 can match the necessary condition that it apply to monitor or high frequency substrate. In the aspect of photophysical properties, we take the 0.3mm P-44 film to measure its photophysical properties. We obtained absorption wavelength that is 245nm and 345nm, and its excitation wavelength is362nm¤Î365nm. Its main area of absorption and excitation is in the region of UV. Furthermore, the transmission spectra of P-44 film showed that visible light transparency were up to 80%. And the refractive index(n) of P-44 film is between 1.37~1.4. In the aspect of thermal mechanical properties, we can know thermal expansion coefficient (CTE) of P-44 film is 19ppm/¢J, and we can also obtain the heat deflection temperature (HDT) of P-44 film is 316¢J. It reveals P-44 possesses low thermal expansion coefficient (CTE) and high heat deflection temperature (HDT). In the aspect of surface, we find P-44 film has low polarity whose main component is van der waals and it has good hydrophobicity.Its contact angle with DI-water is 114.5¢X which greater than 90¢X that proves P-44 film has well hydrophobicity. In the aspect of dielectrical properties, we found that its dielectric constant is between 2.51~2.53 under the condition of1M Hz, and its dielectric loss is between 0.0068~0.0071. It shows P-44 film possesses low dielectric constant that let the effect of parasitic capacitances lowered¡Fand low dielectric loss let the loss of signal reduced. We can plate ITO onto P-44 film successfully, and it could be a flexible transparent conductive film. By the all of the above results, we can realize P-44 film possesses well thermal stabilities¡Bhigh transparency in the region of visible light¡Bgood hydrophobicity¡Blow thermal expansion coefficient (CTE)¡Blow dielectric constant and low dielectric loss. With these great materialIX properties, we can apply it to flexible photpelectric devices in the future.

No description available.

A method using CFD code PHOENICS to simulate flow and heat transfer in a rectangular chemical vapor deposition(CVD) chamber. We focus on the uniformity of heat and flow field. Two different kinds of boundary conditions at substrate, uniform wall heat flux and uniform wall temperature, are used to discuss the effects of the region of inlet, the distance from inlet to substrate, the region of outlet, Re number, and Pr number on uniformity of heat and flow field in chamber. The study finds that high shear stress and high Nu number will happen on the edge of substrate, and they can not improve the heat and flow field uniformity, We suggest that the substrate should be smaller than susceptor. In the case of uniform wall heat flux on substrate, higher shear stress and Nu number on the edge of substrate would result from the condition that the region of inlet is too big. Higher shear stress and Nu number on the region of stagnant point would result from the condition that the region of inlet is too small. Both of them are not good for uniformity. Such kinds of situations also happen in the variable of the distance from inlet to substrate. In uniform wall temperature on substrate, the condition of much higher Nu number on the edge of substrate is more obvious, which effects uniformity more seriously. The uniformity of Nu number could be improved effectively on the condition of region of inlet is 0.864*0.72, Higher distance from inlet to substrate.

ABSTRACT In this thesis we deposit GaN films by magnetron rf sputtering with changes substrate temperature. The electron probe microscope analysis ( EPMA ), scanning electron microscope ( SEM ), photoluminescence measurement ( PL ) and X-ray diffraction ( XRD ) had been used to investigate these GaN films. We find GaN films crystalline quality deposit at low temperature is better then deposit at high temperature. From EPMA analysis we know higher substrate temperature lower oxygen amount of film. The ratio of Ga to N is 1.18 ~ 1.83 in average. The growth rate is about 0.30 £gm/h ~ 0.35 £gm/h in average. Thus changes substrate temperature do not influence growth rate obviously. From SEM and EDS analysis we find the roughness magnitude of films growth on sapphire substrate was smaller than the films growth on silicon substrate. We also find lower substrate temperature the roughness magnitude of films larger on silicon substrate.

Twenty two substrates were developed and tested for two different green roof plant production methodologies. Growth rate analysis of Sedum sp. revealed distinct differences in performance of the mat substrates across a two year time frame with substrate water holding capacity (v/v) being a primary promoter of rapid mat coverage. Tray substrate analysis revealed numerous component options provided similar production speeds, with diverse and beneficial physical properties being described. Zebra and Quagga mussel shells proved to be a sustainable and beneficial component option for both mat and tray substrates. Further substrate component identification resulted in Biochar being investigated for its potential use in green roof media mixtures. The additions of incremental amounts of biochar into control substrates reduced bulk density by up to 20%, while simultaneously increasing volumetric water holding capacity to 54%, 12% greater than that of the control. Sedum plant growth in biochar revealed the lowest shoot dry weights resulting from no biochar additions. Substrate and plant water relationships were explored further with four substrates being planted with four diverse herbaceous and succulent plant communities. Substrate composition and plant community was observed to significantly affect dry down rates. / OMAFRA

No description available.