Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 306 for “"Mass loss"”.
-
Atmospheric Mass Loss And Orbital Evolution Of Exoplanets
<p>The distributions of the semi-major axes and masses of close-in planets (planets within 0.1 AU of their host stars) provide clues to their origin. Over billions of years, the mass and orbital distance are constantly evolving. Tidal forces and atmospheric mass loss, driven by stellar ultraviolet …
-
The Evolution of Massive Stars: The Influence of Initial Composition and Mass Loss
… were evolved with and without the inclusion of mass loss. We have used a moderate mass loss rate with different efficiency factors for main sequence and blue supergiant stars. Our results indicate that all massive stars ignite helium as blue supergiants. Stars with initial masses M(,i(, ))<(, …
-
Luminous blue variable stars: exploring the mass-loss history through a multiwavelength analysis of their ejecta
… Luminous Blue Variable stars (LBVs), which are massive evolved stars subjected to high mass-loss episodes. In particular, the purpose of this thesis is to study the mass-loss history of a subsample of galactic and magellanic LBVs. We analysed data ranging from the mid-IR to the radio, collected …
-
Effects of Atomic Oxygen on the Vacuum-Induced Mass Loss Properties of a Variety of Spacecraft Materials
… individual contributors of spacecraft material mass loss and degradation, but laboratory tests on the synergy are rare. ASTM E595 standardized test procedures were used to determine the Total Mass Loss (TML) and Collected Volatile Condensable Materials (CVCM) values for each material, at which …
-
Investigation of the mass loss, circumstellar environment and evolution of the hydrogen-deficient stars and V838 Mon
Includes bibliographical references (p. 167-175)
-
THE PROGENITORS OF TYPE IIP SUPERNOVAE
Mass-loss prior to core collapse is arguably the most important factor affecting the evolution of a massive star across the Hertzsprung-Russel (HR) diagram, making it the key to understanding what mass-range of stars produce supernova (SN), and how these explosions will appear. It is thought that …
-
The role of accessory minerals in inhibiting bentonite erosion in the geological disposal of higher activity radioactive waste
… in crystalline rock. Currently, quantitative mass loss assessments are based on a 100% montmorillonite buffer and lead to unacceptable mass loss predictions. In practice however, the buffer will be comprised of ≈80% montmorillonite and ≈20% accessory minerals. A better understanding therefore …
-
Residual Engineering Properties of Corroded Conventional Steel, High Chromium Steel and Stainless Steel Reinforcing bars in Concrete
… rebar sizes (No. 3 and No. 4), and for 1%-17% mass loss range. Results from the tests indicate that the yield strength, ultimate strength and ductility of steel reinforcement decreases significantly with the increase of mass loss levels, however, rebar size has a slight effect on these …
-
Surface and groundwater quality impacts of conservation tillage practices on burley tobacco production systems in Southwest Virginia
… and pesticide edge-of-field and deep percolation losses from conventional tillage (CT), strip tillage (ST), and no-till (NT) treatments in a burley tobacco production system. The field experiment results show that the CT treatment yielded more total runoff, 93.6 mm, than ST and NT. Compared to the …
-
Forensic taphonomy: processes associated with cadaver decomposition in soil
… with cadaver decomposition in soil. A pattern of mass loss comprised of an “Early Phase” of slow mass loss, “Intermediate Phase” of rapid mass loss and a “Late Phase” of slow mass loss. Early Phase decomposition coincided with an initial increase in carbon dioxide (CO2) evolution, microbial …
-
Effects of Hydrologic Gradients on Woody Debris Breakdown and Macroinvertebrate Colonization in a Cumberland Plateau Watershed, Eastern Kentucky, U.S.A.
… affected wood processing dynamics (i.e., mass loss and macroinvertebrate colonization and standing stock patterns). Two questions were addressed: (1) do mass loss rates of wood differ across hydrological gradients in stream channels?, and (2) do macroinvertebrate colonization and standing …
-
Fungal Degradation Properties of Young Small Diameter Genetically Modified Quaking Aspen (Populus tremuloides)
… The second and third studies focused on the mass loss differences and cellulose and lignin degradation between trees with different lignin types and contents. In the first study, two methods for rapid laboratory fungal decay tests of very young small diameter (5-15 mm) hybrid poplar (Populus …
-
Characterization of Titanium Alkoxide- Based Sol-Gel Systems and their Behavior in Icephobic Coatings
… was verified using SEM, EDS and AFM techniques. Mass loss kinetics were studied over the temperature range, 30 to 90°C ,for two coating formulations and indicated that the rate at which TPG and glycerol are released to the surface is limited by diffusion through the coating matrix. Additives can …
-
Effects of Litter Production, Biochemistry and Plant Community Composition on Carbon and Nutrient Cycling under Elevated Carbon Dioxide and Tropospheric Ozone.
… occur, and combined with changes in litter biomass production could significantly alter the inputs of soluble sugars, condensed tannins, soluble phenolics, cellulose and lignin to forest soils. Elevated CO2 significantly increased the fluxes to soil of all nutrients (N, P, K, S, Mg, Ca, Cu, Mn, …
-
A Generalized Model for Wall Flame Heat Flux During Upward Flame Spread on Polymers
… on PMMA based on a single input parameter, the mass loss rate. In this study, the model was generalized to predict the heat flux for a broad range of polymers by adding the heat of combustion as a second input parameter. Experimental measurements were conducted to determine mass loss rate during …
-
An experimental approach into the degradation of wind turbine blade coating systems due to rain and weathering
… behaviour. A novel methodology, using surface gloss, was used to quantify erosion and then categorise the specimen into one of the developed erosion stages. Additionally, this approach provides a greater accuracy in erosion quantification than the current method of mass loss measurement and the …
-
Production of zinc iron phosphate glasses by microwave and conventional processing methods
… at 1300 ˚C for 3 hours in electric furnace. The mass loss trends for all samples are increased with the increasing of ZnO and in agreement with the theoretical data calculated from batch compositions. It is found that the mass loss of microwave samples increased about 2 % compared to …
-
Sequential Electron Acceptor Model of Intrinsic Bioremediation at a BTEX Contaminated LUST Site in Laurel Bay, South Carolina
… was used to study the changes in contaminant mass distribution, contaminant mass loss, and mass loss rates for each terminal electron accepting process (TEAP) over time. It was found that the natural attenuation capacity of the aquifer was insufficient to stabilize the plume and prevent it …
-
Where the Ice Ends: Calving and Ice-Ocean Interactions at Helheim Glacier and Beyond
Continued mass loss of the Greenland Ice Sheet has contributed to sea level rise at a rate of 0.8 mm year$^{-1}$ since 2002, with ice dynamics accounting for $66 \pm 8$\% of the mass loss signal. One of the main components of this dynamic mass loss signal is iceberg calving, the detachment of ice …
Page 1 of 16