This is the first systematic experimental investigation of partitioning of Br between apatites and coexisting melts and the uptake of Br by scapolite and sodalite. Twenty-nine partitioning experiments between fluorapatite (FAP) /chlorapatite (ClAP) and coexisting melts were conducted in the system of CaO-P2O5-CaF2-CaCl2NaBr at 1120 degree C to 1400 degree C and atmospheric pressure. The partition coefficients (D) with errors of 1 sigma in parentheses are as follow: <p>DF (ClAP/melt) 3.59(64) at 1120 degree C to 4.13(22) at 1330 degree C <p> DF (FAP/melt) 1.05(4) at 1220 degree C to 1.07 at 1400 degree C <p> DCl (ClAP/melt) 1.07(1) at 1120 degree C to 0.83 at 1330 degree C <p> DCl (FAP/melt) 0.127(2) at 1250 degree C to 0.115 at 1400 degree C <p> DBr (ClAP/melt) 0.32(9) at 1120 degree C to 0.42(5) at 1330 degree C <p> DBr (FAP/melt) 0.020(3) at 1220 degree C to 0.016 at 1400 degree C <p> Seven exchange experiments at one atmospheric pressure and 800 to 1000 degree C yield the following distribution coefficients for Br-Cl exchanges between marialitic scapolite or sodalite and coexisting hydrous NaCl-NaBr melts: KD (marialite-melt) = 0.92 +/- 0.10 and KD (sodalite-melt) = 1.18 +/- 0.10. Therefore, the Cl/Br values in marialitic scapolite and sodalite closely reflect the halogen proportions of their coexisting melts or fluids. <p> The second part of this thesis project analyzes the halogen (F, Cl, Br) contents in natural fluorapatite and scapolite by X-ray fluorescence microprobe (XRF) for Br and electron microprobe (EMPA) for other elements. All selected localities and environments are interesting, because the origins of the parental fluids/melts are controversial. The halogen compositions of 29 natural apatite grains from the Aoshan fluorapatite-magnetite deposit (China), the Oka carbonatite complex (Quebec), and Chinese mantle xenoliths and 36 scapolite samples from the Tieshan Fe-Cu skarn deposit (China), the Nickel Plate gold deposit (British Columbia), and the Grenville pegmatite/skarn/vein deposits (Ontario and Quebec) have been analyzed by electron microprobe (EMPA) and X-ray fluorescence microprobe (XRF). Twenty six whole-rock samples from the Aoshan deposit have also been analyzed by XRF for major and trace elements. <p> Fluorapatite from the Aoshan fluorapatite-magnetite deposit is Cl-bearing with 0.38-0.98 wt% Cl, 1.83-3.45 wt% F, and 0-52 ppm Br. Fluorapatite from Chinese mantle xenoliths has similar halogen compositions to the Aoshan fluorapatite. Fluorapatite from the Oka carbonatite has trace amounts of chlorine (up to 0.052 wt%) and bromine (from 9 to 57 ppm). Applications for the experimental results suggest that the Aoshan Fe-Cu deposit has Cl/Br values comparable to those of mantle sources and that the anomalously low Cl/Br values in Oka fluorapatite require Br-enriched sources. <p> The Cl/Br values (weight) of marialitic scapolite from the Tieshan Fe-Cu deposit cluster around 626 +/- 92, supporting an origin involving hydrothermal brines from associated evaporites. Scapolite-group minerals in the exoskarns of the Nickel Plate Au skarn deposit have Cl/Br from 560 to 570, higher than those (110 to 180) of their counterparts in the endoskarns and vuggy cavities. This variation is attributable to an increased involvement of magmatic water from distal to proximal zones. Similarly, scapolite-group minerals in the Grenvillian U-Th-Mo-REE pegmatite-skarn-vein deposits vary widely in Cl/Br from 80 to 380, indicative of mixed sources of hydrothermal fluids from magmatic sources and from associated sedimentary rocks. <p> The experimentally determined partition coefficients of halogens between minerals (apatites, scapolite, and sodalite) and fluids/melts of this study have wide applications in the interpretation of source and evolution of hydrothermal fluids in mineralization processes and other geological systems. Applications of those partition coefficients to selected mineral deposits and mantle xenoliths confirm their significance.

pas de résumé

pas de résumé

This work presents a model of the fouling mechanism and the evaluation of compressor washing on line. The results of this research were obtained from experimental and computational models. The experimental model analyzed the localization of the particle deposition on the blade surface and the change of the surface roughness condition. The design of the test rig was based on the cascade blade arrangement and blade aerodynamics. The results of the experiment demonstrated that fouling occurred on both surfaces of the blade. This mechanism mainly affected the leading edge region of the blade. The increment of the surface roughness on this region was 1.0 μm. This result was used to create the CFD model (FLUENT). According to the results of the CFD, fouling reduced the thickness of the boundary layer region and increased the drag force of the blade. The model of fouling was created based on the experiment and CFD results and was used to calculate the engine performance in the simulation code (TURBOMATCH). The engine performance results demonstrated that in five days fouling can affect the overall efficiency by 3.5%. The evaluation of the compressor washing on line was based on the experimental tests and simulation of the engine performance. This system demonstrated that it could recover 99% of the original blade surface. In addition, this system was evaluated in a study case of a Power Plant, where it proved itself to be a techno-economic way to recover the power of the engine due to fouling. The model of the fouling mechanism presented in this work was validated by experimental tests, CFD models and information from real engines. However, for further applications of the model, it would be necessary to consider the specific conditions of fouling in each new environment.

High prices in any industry, agricultural especially, tend to spur new investment opportunities. Recent prices for pecans have been high relative to their historical pattern, suggesting investment opportunities for pecans. Prior to any investment, the investor needs to know what products consumers are demanding and how profitable it is to grow those products. This study assessed Texas consumers' preferences for pecan products and the profitability of growing pecans in the central Texas region. A choice experiment was conducted amongst Texas consumers to reveal consumers' preferences and determine their willingness-to-pay for the attributes comprising pecan products. A stochastic production model was formulated to determine the profitability of three different types of pecan orchards: a native orchard with no irrigation, an improved varieties orchard with irrigation, and an improved varieties orchard without irrigation. Results from the choice experiment indicated that consumers preferred large size pecans, native variety pecans, pecan halves, United States-grown pecans, and Texas-grown pecans. The choice experiment also found that consumers were heterogeneous in their preferences for all attributes except pecan variety and U.S. origin. Results from the stochastic production model indicated that the most profitable pecan orchard in central Texas was the irrigated improved orchard.

Esta tesis es dividida en tres capítulos que se refieren a dos temas diferentes. El segundo capítulo se concentra en los efectos incentivos de bajar salarios llanos y su papel en la ayuda del fracaso de coordinación vencido. Los resultados débilmente apoyan los efectos positivos de bajar salarios llanos. Los dos papeles en los terceros y cuartos capítulos relacionan los estudios de la incertidumbre de información de riesgo y ambigüedad en juegos de entrada de mercado. Estudiamos experimentalmente decisiones bajo la incertidumbre de riesgo y ambigüedad en juegos de entrada de mercado, que captura los rasgos básicos de los fenómenos sobre la entrada en el mercado. La tarea importante es averiguar si la participación excesiva está relacionada con los tipos de información de riesgo y ambigüedad, y si las decisiones son diferentes en riesgo y ambigüedad en ambientes estratégicos. Encontramos la ambigüedad que busca en un ajuste de mercado de un ambiente relativo del mercado de información arriesgado y ambiguo en la correspondencia fija. Sin embargo, en un ambiente no relativo del mercado de información arriesgado y ambiguo, la busca de ambigüedad es saliente en la correspondencia arbitraria, pero no en la correspondencia fija. Encontramos que los efectos de ambigüedad en juegos estratégicos no dependen de si el riesgo y la ambigüedad son puestos en contextos relativos o no relativos, pero en la complejidad estratégica en los juegos. Más fuerte la complejidad estratégica es, más saliente la ambigüedad efectúa. / This thesis is divided into three chapters that refer to two different topics. The second chapter focuses on the incentive effects of lowering flat wages and its role in helping overcome coordination failure. The results weakly support the positive effects of lowering flat wages. The two papers in the third and fourth chapters relate the studies of information uncertainty of risk and ambiguity in market entry games. We study experimentally decisions under uncertainty of risk and ambiguity in market entry games, which captures the basic features of the phenomena over entry in the market. The important task is to find out whether the excessive participation is related to the information types of risk and ambiguity, and whether decisions are different in risk and ambiguity in strategic environments. We find ambiguity seeking in a market setting of a comparative environment of risky and ambiguous information market in fixed matching. However, in a non-comparative environment of risky and ambiguous information market, ambiguity seeking is salient in random matching, but not in fixed matching. We find that ambiguity effects in strategic games do not depend on whether risk and ambiguity are put in comparative or non-comparative contexts, but on the strategic complexity in the games. The stronger the strategic complexity is, the more salient the ambiguity effects.

The topic of this study is using Total Physical Response (TPR) in teaching English adjectives to 11-year-old pupils. The objective of this study is to investigate whether the TPR method is effective in teaching English adjectives. The researcher used a quasi-experiment to design this study. The population was the pupils aged 11 in a middle school in Kristianstad. 30 pupils were selected as samples and divided into two groups: one experimental group and one control group. The steps of this experiment were: (1) the experimental group was taught by the TPR method; (2) the control group and the experimental group were given the same post-test. In order to investigate whether there is a necessity to adopt new English vocabulary teaching technique for these pupils, two questionnaires were deliberated; the first questionnaire was for all testees and the second questionnaire was just for the experimental group. The result of the study showed the pupils’ achievements in the experimental group were improved by the TPR method. The mean score of the experimental group was much higher than that of the control group. The p-value of this test was 0.0002 less than 0.01 which showed strong evidence that the results were not achieved coincidentally. The effect size of this study was 2.59 more than 0.8 which indicated that the TPR method has significant effectiveness in teaching English adjectives. The questionnaires indicated that TPR was the new English vocabulary teaching technique that the pupils need.

In fractured geologic media, flow and contaminant transport are predominantly controlled by the fractures, their distribution and connectivity. The accurate characterization of fractured geologic medium, imaging of fracture patterns and their connectivity have been a challenge for decades. Given the complexities of fractured networks in the subsurface and Dense Non Aqueous Phase Liquid (DNAPL) contamination, in this thesis, transient hydraulic tomography (THT), a recently developed tool for characterizing aquifer heterogeneity is evaluated under laboratory conditions to delineate discrete fractures. Laboratory experiments and modeling studies are also conducted to understand TCE plume behavior. A dolomite rock sample, which is 91.5 cm in length, 60.5 cm in height and 5 cm thick, was fractured in the laboratory to perform the experiments. After the fractured block was enclosed in a flow cell, flow-through and pumping tests were conducted to characterize the fractured rock block. The data from the pumping tests were then analyzed using the SSLE code developed by Zhu and Yeh [2005] and transient hydraulic tomography (THT) was conducted to image the fracture pattern and their connectivity through the delineation of K and Ss distributions (the tomograms). Synthetic pumping tests, identical in configuration to the laboratory ones were also conducted using HydroGeoSphere (HGS) [Therrien et al, 2009] in a synthetic replica of the fractured block to compare the observed and simulated drawdowns. Then synthetic THT analysis was performed utilizing the synthetic pumping test data to compare the tomograms obtained from the THT analysis of synthetic and laboratory pumping tests. Results suggest that the THT analysis of multiple laboratory pumping tests captured the fracture pattern and their connectivity quite well and they became more vivid with the additional pumping tests. The estimated high hydraulic conductivity (K) and low specific storage (Ss) zones clearly show the fractures and their connectivity. The pattern of K and Ss tomograms obtained from the analyses of synthetic and laboratory pumping tests were similar. Estimated K and Ss values for the fractures and the matrix may not exactly replicate the actual K and Ss values for the fractured rock, but the model also provides uncertainty estimates associated with the resulting K and Ss tomograms. In this study, two cases of transient hydraulic tomography (THT) analysis of the laboratory pumping tests were performed by changing the location of 2nd and 3rd pumping tests among the three to examine if there is any significant impact of these pumped location on the pattern of resulting hydraulic conductivity (K) and specific storage (Ss). The initial pumping test was the same for two cases. Results show that the patterns of estimated K and Ss tomograms obtained from these two cases are similar, although the pumped locations (2nd and 3rd tests among the three) utilized for the inversion were different for two cases suggesting that the location of these later pumping tests does not significantly impact the estimates for this fractured rock block. However, the initial test should be selected carefully as that seems to set the pattern of the tomograms. The estimated K and Ss tomograms were validated by predicting five independent pumping tests conducted in the fractured rock block. These five pumping tests were not included during the construction of the K and Ss tomograms. For most of the independent pumping tests, good correspondence between the simulated and observed drawdown was achieved. The study indicates that, it is possible to delineate discrete fractures, their pattern and connectivity by carefully applying of THT analysis of multiple pumping tests based on the inverse code SSLE [Zhu and Yeh, 2005]. In addition, hydraulic tomography seems to be a cost effective tool for characterizing fractured rock since it does not require the detailed information on fracture geometry parameters such as aperture, trace length, orientation, spatial distribution, and connectivity, which are difficult to quantify. These parameters are usually unavailable between boreholes. Therefore, THT appears to be a promising approach in delineating fractures and their connectivity in subsurface. However, it is still at the early stage as the study was conducted in the laboratory under controlled conditions. Small scale field experiments need to be conducted to validate THT as a tool for the characterization of hydraulic parameters of fractured rocks. Upon completion of the hydraulic characterization, several conservative tracer tests were conducted using bromide (Br-) as a conservative tracer to aid in the design of TCE dissolution experiment. Once the tracer experiments were completed, a known volume of pure phase TCE was injected at a known location in the flow cell to create a well-defined source zone. A constant hydraulic gradient was maintained by fixing the hydraulic heads at the two head tanks to induce steady groundwater flow through the flow cell. Water samples were obtained at a down gradient monitoring port for 3 months to obtain a long-term breakthrough curve of TCE in the aqueous phase. The purpose of this experiment was to study TCE dissolution behaviour in the fractured rock sample. Then HydroGeoSphere (HGS) was used to model the aqueous phase TCE transport using two separate approaches: 1) the Discrete Fracture Network modeling approach and 2) the stochastic continuum approach, to investigate whether they can capture the dissolution behavior. Both approaches were able to capture the pattern of the breakthrough curve in the fractured rock. The discrete fracture approach captured the observed TCE plume and the dissolution behavior quite well. On the other hand, the stochastic continuum approach, in which the fractured rock block was treated as porous medium having a heterogeneous K field obtained from THT analysis, also appeared to be promising in capturing the aqueous phase transport of TCE. Despite some early time deviation, the simulated breakthrough curve captured the overall observed concentration profile. However, the stochastic continuum approach seems to be more cost effective as it does not require detailed information about fracture aperture and their spatial distribution which are difficult if not impossible to obtain between boreholes. Note that, the studies were conducted based on a laboratory experiment conducted in a controlled environment. The experimental block was well characterized and the geometry of the experimental block as well as the flow through the system was well understood from the hydraulic and tracer experiments. Thus small scale field experiment is required to support this conclusion.

This is the first systematic experimental investigation of partitioning of Br between apatites and coexisting melts and the uptake of Br by scapolite and sodalite. Twenty-nine partitioning experiments between fluorapatite (FAP) /chlorapatite (ClAP) and coexisting melts were conducted in the system of CaO-P2O5-CaF2-CaCl2NaBr at 1120 degree C to 1400 degree C and atmospheric pressure. The partition coefficients (D) with errors of 1 sigma in parentheses are as follow: <p>DF (ClAP/melt) 3.59(64) at 1120 degree C to 4.13(22) at 1330 degree C <p> DF (FAP/melt) 1.05(4) at 1220 degree C to 1.07 at 1400 degree C <p> DCl (ClAP/melt) 1.07(1) at 1120 degree C to 0.83 at 1330 degree C <p> DCl (FAP/melt) 0.127(2) at 1250 degree C to 0.115 at 1400 degree C <p> DBr (ClAP/melt) 0.32(9) at 1120 degree C to 0.42(5) at 1330 degree C <p> DBr (FAP/melt) 0.020(3) at 1220 degree C to 0.016 at 1400 degree C <p> Seven exchange experiments at one atmospheric pressure and 800 to 1000 degree C yield the following distribution coefficients for Br-Cl exchanges between marialitic scapolite or sodalite and coexisting hydrous NaCl-NaBr melts: KD (marialite-melt) = 0.92 +/- 0.10 and KD (sodalite-melt) = 1.18 +/- 0.10. Therefore, the Cl/Br values in marialitic scapolite and sodalite closely reflect the halogen proportions of their coexisting melts or fluids. <p> The second part of this thesis project analyzes the halogen (F, Cl, Br) contents in natural fluorapatite and scapolite by X-ray fluorescence microprobe (XRF) for Br and electron microprobe (EMPA) for other elements. All selected localities and environments are interesting, because the origins of the parental fluids/melts are controversial. The halogen compositions of 29 natural apatite grains from the Aoshan fluorapatite-magnetite deposit (China), the Oka carbonatite complex (Quebec), and Chinese mantle xenoliths and 36 scapolite samples from the Tieshan Fe-Cu skarn deposit (China), the Nickel Plate gold deposit (British Columbia), and the Grenville pegmatite/skarn/vein deposits (Ontario and Quebec) have been analyzed by electron microprobe (EMPA) and X-ray fluorescence microprobe (XRF). Twenty six whole-rock samples from the Aoshan deposit have also been analyzed by XRF for major and trace elements. <p> Fluorapatite from the Aoshan fluorapatite-magnetite deposit is Cl-bearing with 0.38-0.98 wt% Cl, 1.83-3.45 wt% F, and 0-52 ppm Br. Fluorapatite from Chinese mantle xenoliths has similar halogen compositions to the Aoshan fluorapatite. Fluorapatite from the Oka carbonatite has trace amounts of chlorine (up to 0.052 wt%) and bromine (from 9 to 57 ppm). Applications for the experimental results suggest that the Aoshan Fe-Cu deposit has Cl/Br values comparable to those of mantle sources and that the anomalously low Cl/Br values in Oka fluorapatite require Br-enriched sources. <p> The Cl/Br values (weight) of marialitic scapolite from the Tieshan Fe-Cu deposit cluster around 626 +/- 92, supporting an origin involving hydrothermal brines from associated evaporites. Scapolite-group minerals in the exoskarns of the Nickel Plate Au skarn deposit have Cl/Br from 560 to 570, higher than those (110 to 180) of their counterparts in the endoskarns and vuggy cavities. This variation is attributable to an increased involvement of magmatic water from distal to proximal zones. Similarly, scapolite-group minerals in the Grenvillian U-Th-Mo-REE pegmatite-skarn-vein deposits vary widely in Cl/Br from 80 to 380, indicative of mixed sources of hydrothermal fluids from magmatic sources and from associated sedimentary rocks. <p> The experimentally determined partition coefficients of halogens between minerals (apatites, scapolite, and sodalite) and fluids/melts of this study have wide applications in the interpretation of source and evolution of hydrothermal fluids in mineralization processes and other geological systems. Applications of those partition coefficients to selected mineral deposits and mantle xenoliths confirm their significance.

The aim of this thesis is to study the possibility of the existence of a specialist in bone tools manufacturing during the Mesolithic. The thesis describes the climate during the Mesolithic, argues for an experimental approach, and describes social organization in hunter-gatherer-groups and the processes behind cultural transmission. It also gives some examples of excavation sites in Scandinavia. An experiment simulating a teaching situation is made, in addition to the theoretical information, with the intent to explore how advanced the crafting of bone really is. The physical result is then studied and documented. The outcome is then interpreted and discussed in connection with the theoretical knowledge and observations during the experiment. The end result points to the non-existence of specialists in bone crafting during the Mesolithic. Some reflection on the discussed subjects concludes the thesis.