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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
431

Bioavailability of trace metals to plants

Voigt, Astrid January 2003 (has links)
No description available.
432

Towards Automating Structural Analysis of Complex RNA Molecules and Some Applications In Nanotechnology

Parlea, Lorena Georgeta 02 June 2015 (has links)
No description available.
433

Density distribution of nuclei: From charge radii to bubbles in Covariant Density Functional Theory (CDFT)

Perera, Udeshika C. 10 May 2024 (has links) (PDF)
This dissertation applies covariant density functional theory (CDFT), one of the modern theoretical approaches for describing finite nuclei and neutron stars, to investigate the density distribution of nuclei, which is a manifestation of the nodal structure of the single-particle states in physical phenomena, including charge radii and bubbles. A systematic global investigation of differential charge radii has been performed within the CDFT framework for the first time. Available experimental data is compared with theoretical charge radii across the neutron shell closures at N = 28, 50, 82, and 126. Odd-even staggering (OES) in charge radii are believed to be primarily caused by the pairing. Our research proposes a new approach where a considerable contribution to OES in charge radii is provided by the fragmentation of the single-particle content of the ground state in odd-mass nuclei due to particle-vibration coupling. The proton-neutron interaction explained with the nodal structure of the products of the proton and neutron wave functions. However, proton core is responsible for a major contribution to the buildup of differential charge radii. This interaction between protons and neutrons causes a rearrangement of the single-particle density of occupied proton states, which affects the charge radii. According to our microscopic analysis, the shape of the proton potential, the overall proton density, and the energies of the single-particle proton states are all influenced by self-consistency effects, but they have a minimal impact on the differential charge radii. A detailed and microscopic analysis of bubble physics strongly suggests that single-particle processes are primarily responsible for the creation of bubble shapes in superheavy nuclei. The creation of bubble structure is also influenced by nuclear saturation processes and self-consistency effects, and it is dependent on the availability of low-�� single-particle states for occupation since single-particle densities. For the first time, we investigated how nuclear bubbles are formed in the central classically prohibited area at the bottom of the wine bottle potentials, resulting in decreased s state densities at r = 0.
434

Romantic and Realistic Elements in the Theater of Don Manuel Tamayo y Baus

Booth, Venita Keown 08 1900 (has links)
A critical study of the drama of Tamayo y Baus.
435

Petrologic Significance of Multiple Magmas in the Quottoon Igneous Complex, NW British Columbia and SE Alaska

Thomas, Jay Bradley Jr. 26 June 1998 (has links)
The quartz dioritic Quottoon Igneous Complex (QIC) is a major Paleogene (65-56 Ma) magmatic body in NW British Columbia and SE Alaska that was emplaced along the Coast shear zone (CSZ). The QIC contains two different igneous suites that provide information about source regions, magmatic processes and evolving tectonic regimes that changed from a dominantly convergent to a dominantly strike-slip regime between 65 to 55 Ma. Heterogeneous suite I rocks (e. g. along Steamer Passage) have a pervasive solid-state fabric, abundant mafic enclaves and dikes, metasedimentary screens, and variable color indices (25-50). The homogeneous suite II rocks (e. g. along Quottoon Inlet) have a weak (to absent) fabric developed in the magmatic state (aligned feldspars, melt filled shears), and more uniform color indices (24-34) than in suite I. Suite I rocks have Sr concentrations <750 ppm, avg. LaN/YbN = 10.4, and initial 87Sr/86Sr ratios that range from 0.70513 to 0.70717. The suite II rocks have Sr concentrations >750 ppm, avg. LaN/YbN = 23.1, and initial 87Sr/86Sr ratios that range from 0.70617 to 0.70686. This study proposes that the parental QIC magma (initial 87Sr/86Sr = 0.706) can be derived bypartial melting of an amphibolitic source reservoir at lower crustal conditions. Geochemical data (Rb, Sr, Ba and LaN/YbN) and initial 87Sr/86Sr ratios preclude linkages between the two suites by fractional crystallization or assimilation and fractional crystallization (AFC) processes. The suite I rocks are interpreted to be the result of magma mixing between the QIC parental magma and a mantle derived magma. The samples do not lie along a single mixing line due to continued evolution through fractional crystallization/AFC processes subsequent to magma mixing. The suite II rocks may be generated by AFC. Initial 87Sr/86Sr ratio data suggests that similar processes to those that affected the QIC may also have operated during the generation of other portions of the Great Tonalite Sill of southeast Alaska. / Master of Science
436

The music of architecture

Sheppard, Marilyn 14 December 2011 (has links)
Music, as a performing art, transports us to distant moments and spaces than those we are in the present time. A hundred musicians playing Bruckner's Scherzo on Symphony No. 7 could make us feel emotionally moved; it could make us feel joy, anger, anguish, delight, peace, fear, freedom. Music has the ability to change our mood, to make us go through a series of feelings. This, I believe, has to do with how it involves you in it. Arthur Schopenhauer also says: "The effect of music on the mind, so penetrating, so immediate, so unfailing, and also the after-effect that sometimes follows it, consisting in a specially sublime frame of mind, are explained by the passive nature of hearing just described" This penetrating component of music, so immediate, of which Schopenhauer speaks, is how the Sublime is experienced through it. Music could even elevate the soul of those who are most open to perceive it. What is that "sublime" moment that happens when you are listening to a live orchestra and get moved by the experience? Are we capable of achieving that moment through the use of architectural elements alone? I believe the answer is yes. There is more to the moment than just the music itself, and that a "sublime" moment can be experienced in many contexts. There are elements that are common to this experience, primarily the presence of the Four Classical Elements. With this in mind, I came to the idea that by including Air, Fire, Earth and Water into my project, then I would be a step closer to having the users go through a sublime experience. / Master of Architecture
437

Geological, mineralogical and geochemical characterisation of the heavy rare earth-rich carbonatites at Lofdal, Namibia

Do Cabo, Vistorina Nandigolo January 2013 (has links)
This study considered the geology, mineralogy, geochemistry, formation and evolution of the heavy rare earth element (HREE) mineralised Lofdal alkaline carbonatite complex (LACC), which is located on the Bergville and Lofdal farms northwest of Khorixas, in the Kunene Region of the Republic of Namibia. . Field methods used included mapping, ground and hyperspectral airborne geophysics, and sampling. Analytical techniques used were optical petrography and CL, XRF, ICP-AES, backscattered and secondary electron imaging, electron microprobe, LA-ICP-MS, leaching, as well as carbon and oxygen stable isotope determination. The LACC comprises a swarm of dykes, mainly calcite carbonatite but also dolomite and ankerite carbonatite dykes (classified into five types) and two newly discovered plugs of calcite carbonatite (‘Main’ and ‘Emanya’), with associated dykes and plugs of phonolites, syenites and rare mafic rocks. These all intrude into the Huab Metamorphic Complex basement rocks within a NE-SW shear zone over 30 km long. The main HREE host mineral is xenotime-(Y). It occurs in highly oxidised iron-rich calcite carbonatite dykes mantling and replacing zircon, associated with hematite, thorite and apatite, or associated with monazite-(Ce), synchysite-(Ce), and parisite-(Ce), replacing the fluorocarbonates; it also forms aggregates in ankerite carbonatite. Although xenotime-(Y) occurs throughout the paragenetic sequence, there is much evidence for hydrothermal fluid activity at Lofdal, altering the dykes, and taking xenotime-(Y) into brecciated carbonate veins in albitised country rock (fenite). Radiogenic (Sr, Nd-Sm, U-Pb) and C and O stable isotope studies confirm that the carbonatite, derived from an enriched mantle, is the source of the REE. Mineralisation was contemporaneous with carbonatite emplacement at 765 ±16 Ma. Magmatic fluids >300°C were diluted with cool meteoric fluids. Abundant fluorite and carbonate indicate roles for F- and CO32- in addition to Cl- in REE transport. These ligands form the most stable complexes with HREE and since xenotime is soluble in concentrated alkali halide solutions, they could have preferentially transported and then deposited xenotime. Many of the features of Lofdal are common to other REE-rich carbonatite complexes but the xenotime-(Y) abundance is so far unique. The high amount of fluid activity in shear zones around the dyke swarm and probably a higher proportion of HREE in the original magmas seem to be the main differentiating features.
438

Trace element analysis of powdered beverages and other materials by x-ray flourescence [sic]

Dellai, Cheryl K January 2011 (has links)
Digitized by Kansas Correctional Industries
439

The value of trace minerals in bovine fattening rations

Oltjen, Robert Raymond. January 1958 (has links)
Call number: LD2668 .T4 1958 O52
440

Binding of trace elements with various dietary fiber sources

Hassani, Bibizahra, 1959- January 1989 (has links)
Mineral binding capacity of rice bran, oat hull, soy bran, wheat bran, peanut, apple, tomato, and barley fiber were investigated. Defatted fibers were analyzed for ash, protein, acid detergent fiber, and lignin. The fibers were washed with 1% HCl and Acid washed samples were studied for their mineral binding ability. The minerals tested were zinc, copper, and magnesium. Analysis of acid washed samples showed that most of the original minerals had been stripped from the fiber. In most of the fibers studied, the order of binding was copper > zinc > magnesium. Among the eight fibers studied, oat hull and apple fiber had the lowest consistent binding capacity for the three minerals investigated. This in vitro binding study has been run to duplicate intestinal condition of pH 6.8.

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