5 resultados para Rhenium(I) tricarbonyl complex
em Digital Commons at Florida International University
Resumo:
Pronunciation training has been traditionally viewed as of limited importance in a communicatively oriented foreign language curriculum (Pennington & Richards, 1986). Many language instructors seemingly deny the usefulness of phonetic training and rely on a listen-and-repeat method with the use of audiotapes (Bate, 1989; Callamand & Pedoya, 1984; Jones, 1997). Beginners in French classes face the challenge of mastering a complex sound and grapheme-phoneme correspondence system without the benefit of specific instruction. Their pronunciation errors develop mostly from bad habits while decoding from print to sound (Dansereau, 1995). ^ The purpose of this study was to investigate the effectiveness of basic phonetic/phonics instruction on reading pronunciation accuracy in a French I language course. ^ The sample consisted of two groups of French I students from Florida International University, who received the same instruction in French language and culture during the fall semester of 1999. Only the experimental group received additional phonetic/phonics training. ^ The instrument consisted of three recorded reading tasks: isolated familiar words, isolated unfamiliar words, and dialogue. Research questions were analyzed using a one-way multivariate analysis of variance. Significant differences were found between the two groups on scores for each of the three sections of the instrument, and on the total scores. These findings support the hypothesis of the study and reveal the effectiveness of phonetic/phonics training for beginners of French. ^ The findings imply that beginning language students should receive the minimum knowledge they need to master the French phoneme-grapheme (sound-spelling) system. ^
Resumo:
Intraplate volcanism that has created the Hawaiian-Emperor seamount chain is generally thought to be formed by a deep-seated mantle plume. While the idea of a Hawaiian plume has not met with substantial opposition, whether or not the Hawaiian plume shows any geochemical signal of receiving materials from the Earth’s Outer Core and how the plume may or may not be reacting with the overriding lithosphere remain debatable issues. In an effort to understand how the Hawaiian plume works I report on the first in-situ sulfides and bulk rock Platinum Group Element (PGE) concentrations, together with Os isotope ratios on well-characterized garnet pyroxenite xenoliths from the island of Oahu in Hawaii. The sulfides are Fe-Ni Monosulfide Solid Solution and show fractionated PGE patterns. Based on the major elements, Platinum Group Elements and experimental data I interpret the Hawaiian sulfides as an immiscible melt that separated from a melt similar to the Honolulu Volcanics (HV) alkali lavas at a pressure-temperature condition of 1530 ± 100OC and 3.1±0.6 GPa., i.e. near the base or slightly below the Pacific lithosphere. The 187Os/188Os ratios of the bulk rock vary from subchondritic to suprachondritic (0.123-0.164); and the 187Os/188Os ratio strongly correlates with major element, High Field Strength Element (HFSE), Rare Earth Element (REE) and PGE abundances. These correlations strongly suggest that PGE concentrations and Os isotope ratios reflect primary mantle processes. I interpret these correlations as the result of melt-mantle reaction at the base of the lithosphere: I suggest that the parental melt that crystallized the pyroxenites selectively picked up radiogenic Os from the grain boundary sulfides, while percolating through the Pacific lithosphere. Thus the sampled pyroxenites essentially represent crystallized melts from different stages of this melt-mantle reaction process at the base of the lithosphere. I further show that the relatively low Pt/Re ratios of the Hawaiian sulfides and the bulk rock pyroxenites suggest that, upon ageing, such pyroxenites plus their sulfides cannot generate the coupled 186Os- 187Os isotope enrichments observed in Hawaiian lavas. Therefore, recycling of mantle sulfides of pyroxenitic parentage is unlikely to explain the enriched Pt-Re-Os isotope systematics of plume-derived lavas.
Resumo:
This qualitative study explored the unique experiences of expatriates in adjusting to cross-cultural situations and confronting challenges in global journeys. Personal narratives written by previous or current expatriates were collected as qualitative data and content analysis was conducted. The results clarified three themes contributing to the complex process of cross-cultural adaptation.
Resumo:
The Rio San Juan Complex is an important occurrence of high pressure/low temperature rocks in the circum-Caribbean region which contains both coherent blueschist units and two varieties of melange in the same area. The melanges contain a diverse assemblage of blocks of various sizes, different degrees of metamorphism, and mineral assemblages. Some high pressure blocks show two stages of metamorphism. The earliest stage is characterized by high pressure-low temperature conditions and the second stage is characterized by high pressure-lower temperature conditions. The geochemistry of thirteen samples from the Rio San Juan Complex has been studied and data have been compared with rocks of adjacent regions. Geochemical evidence indicates that rocks from the Rio San Juan Complex have predominant calc-alkaline affinities with subordinate tholeiitic affinities. This suggests that they have a multiple tectonic provenance.
Resumo:
We are able to give a complete description of four-dimensional Lie algebras g which satisfy the tame-compatible question of Donaldson for all almost complex structures J on g are completely described. As a consequence, examples are given of (non-unimodular) four-dimensional Lie algebras with almost complex structures which are tamed but not compatible with symplectic forms.? Note that Donaldson asked his question for compact four-manifolds. In that context, the problem is still open, but it is believed that any tamed almost complex structure is in fact compatible with a symplectic form. In this presentation, I will define the basic objects involved and will give some insights on the proof. The key for the proof is translating the problem into a Linear Algebra setting. This is a joint work with Dr. Draghici.