987 resultados para 511


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C2-C8 hydrocarbons (36 compounds identified) from 56 shipboard sealed, deep-frozen core samples of DSDP Leg 71, Site 511, Falkland Plateau, South Atlantic, were analyzed by a combined hydrogen stripping-thermovaporization method. Concentrations, which represent hydrocarbons dissolved in the pore water and adsorbed to the mineral surfaces of the sediment, vary from 24 ng/g of dry weight sediment in Lithologic Unit 4 to 17,400 ng/g in Lithologic Unit 6 ("black shale" unit). Likewise, the organic carbon normalized C2-C8 hydrocarbon concentrations range from 104 to 3.5 x 105 ng/g Corg. The latter value is more than one order of magnitude lower than expected for petroleum source beds in the main phase of oil generation. The low maturity at 600 meters depth is further supported by light hydrocarbon concentration ratios. The change of the kerogen type from Lithologic Unit 5 (Type III) to 6 (Type II) is evidenced by changes in the C6 and C7 hydrocarbon composition. Redistribution phenomena are observed close to the Tertiary-Cretaceous unconformity and at the contact between the "black shale" unit and the overlying Cretaceous chalks and claystones. Otherwise, the low molecular weight hydrocarbons in Hole 511 are formed in situ and remain at their place of formation. The core samples turned out to be contaminated by large quantities of acetone, which is routinely used as a solvent during sampling procedures onboard Glomar Challenger.

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Calcareous nannofossils from upper Campanian-lower Maestrichtian Deep Sea Drilling Project Leg 71 Cores 511-23 and 511-24 are described and correlated with assemblages of similar age from piston and drill cores on the Falkland Plateau, South Atlantic Ocean. The Leg 71 cores partially fill a drilling gap of at least 20 meters left within a thick (50 m) carbonate section first drilled by DSDP Leg 36 at Site 327. Cores 511-23 and 511-24 both fall within the upper portion of the Biscutum coronum Zone of Wind and demonstrate an overlap in the range of Monomarginatus quaternarius with the ranges of M. pectinatus, Misceomarginatus pleniporus, and Biscutum coronum across the Campanian/ Maestrichtian boundary. Resolution of the sequence of highest occurrence datums for the latter species must await the recovery of a more complete section. Comparison of the Site 511 assemblages with those from Mas Orcadas Core 07-75-44 to the north confirms earlier speculation that the Falkland Plateau served as an important boundary between major water masses during the Late Cretaceous.

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The application of Raman spectroscopy to the study of the copper chloride minerals nantokite, eriochalcite and claringbullite has enabled the vibrational modes for the CuCl, CuOH and CuOH2 to be determined. Nantokite is characterised by bands at 205 and 155 cm-1 attributed to the transverse and longitudinal optic vibrations. Nantokite also has an intense band at 463 cm-1, eriochalcite at 405 and 390 cm-1 and claringbullite at 511 cm-1. These bands are attributed to CuO stretching modes. Water librational bands at around 672 cm-1 for eriochalcite have been identified and hydroxyl deformation modes of claringbullite at 970, 906 and 815 cm-1 are observed. Spectra of the three minerals are so characteristically different that the minerals are readily identified by Raman spectroscopy. The minerals are often determined in copper corrosion products by X-ray diffraction. Raman spectroscopy offers a rapid, in-situ technique for the identification of these corrosion products.

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Information and communication technology (ICT) curriculum integration is the apparent goal of an extensive array of educational initiatives in all Australian states and territories. However, ICT curriculum integration is neither value neutral nor universally understood. The literature indicates the complexity of rationales and terminology that underwrite various initiatives; various dimensions and stages of integration; inherent methodological difficulties; obstacles to integration; and significant issues relating to teacher professional development and ICT competencies (Jamieson-Proctor, Watson, & Finger, 2003). This paper investigates the overarching question: Are ICT integration initiatives making a significant impact on teaching and learning in Queensland state schools? It reports the results from a teacher survey that measures the quantity and quality of student use of ICT. Results from 929 teachers across all year levels and from 38 Queensland state schools indicate that female teachers (73% of the full time teachers in Queensland state schools in 2005) are significantly less confident than their male counterparts in using ICT with students for teaching and learning, and there is evidence of significant resistance to using ICT to align curriculum with new times and new technologies. This result supports the hypothesis that current initiatives with ICT are having uneven and less than the desired results system wide. These results require further urgent investigation in order to address the factors that currently constrain the use of ICT for teaching and learning.

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As part of a decision making process, the controlling process in construction companies can be supported by computer application that provides faster and reliable decision. This paper discusses the development of a knowledge-based decision support system for controlling construction companies’ business performance. The knowledge-base was developed using questionnaire survey and case studies. A questionnaire survey was conducted to identify potential problems that can occur in construction companies as well as the source of the problems and their impact on companies’ performance. Case studies were used to identify and analyse various corrective actions. The result of the study shows that decision support system using knowledge-based management system improves the effectiveness and the efficiency of decision making process for selecting the most appropriate corrective action that can improve construction companies’ performance. The application, which had been developed in this research, was designed to support the process of controlling construction companies’ business performance and to assist young manager in selecting the most optimum corrective actions for the problems related to achieving companies’ objectives. This computer application can be used as a learning tool for identifying potential problems that a construction company faces and the most optimum corrective action.