The HAbitability, Brine Irradiation and Temperature Package (HABIT) instrument of the ExoMars Surface Platform will investigate the present day habitability of Mars at the near surface environment. This instrument includes three Atmospheric Temperature Sensor's (ATS's) which are similar to the ones previously used on the Rover Environmental Monitoring Station (REMS) of the Mars Science Laboratory (MSL) rover, that has now been operating on Mars for more than four years. The ATS of REMS is only used to provide the air temperature, however on HABIT it will be used furthermore to provide information about winds and heat transfer at the surface of Mars. The retrieval method needs to be further investigated and validated. This master thesis is aimed at three goals: 1) the development and testing of an Earth Scaled Atmospheric Temperature Sensor (ESATS) to test the retrieval concept; 2) the validation with other Earth-based standard wind sensing technologies under outdoors uncontrolled conditions; and 3) the analysis of the existing observations of the ATS of REMS on Mars to get a better understanding of its expected future performance on HABIT once it operates on Mars. The ESATS is an up-scaled semi-autonomous prototype version of an ATS which consists of a rod of different size and material to those that are used on REMS and will be used on HABIT. The rod shall be heated from the base where it is attached to. The temperature profile shall be measured at three different measurement points. All these temperatures are different from the one of the atmosphere to which the rod is exposed to. The temperature profile along the rod changes depending on the air temperature, air density and the wind speed because of the convective heat transfer. A preliminar analysis is used to define what is the ideal length of the rod, and what is the material that is best adapted for this experimental prototype. Since the air density is needed to retrieve the wind speed, the pressure will be monitored as well. In parallel, a second wind measuring technique based on the dynamic pressure changes detected in a Pitot tube is used as control. The measuring campaign is subdivided in several stages: 1) The first part will take place in a laboratory, where the system is exposed to static conditions with no heating and no wind, which means that there is no forced convection caused by wind. In this setup all sensors are calibrated against one another and with help of a reference resistor the temperature sensors are also calibrated to 273.15K. Additionally different Operational Amplifiers (OpAmps) will be used to observe how the noise level is affecting the measurements, so that the best one will be used in the end. 2) Furthermore, the best position to place the intermediate temperature sensor is investigated by testing one of the rods with different locations of the middle temperature sensor. 3) Next, also within the laboratory environment, the different rods are used to obtain the temperature profile and retrieve the air temperature and heat transfer values, solving the equations that describe the heat transfer problem under static conditions. 4) The second part of the measurement campaign will take place outdoors, where the ESATS is exposed to forced convection due to wind. In this setting first the influence of the Sun on the system is measured, as it is important to know, if the measurement can be performed when the illumination conditions change. 5) Next, the system is tested with the 50cm rod in long term tests with the reference measurement of a commercial weather station (HOBO) next to it. With the data obtained the convective heat transfer method is used and the retrieved wind speed is compared to the one received from the HOBO. Finally, to get a better understanding of its expected future performance on HABIT once it operates on Mars, the data of the ATS of REMS is used to perform the wind speed retrieval for Mars and to compare it with the data received from the REMS wind sensor. It is only operating during daytime and has still difficulties to retrieve a precise wind speed. The measurement campaign has given several information about ATS in general. First it was decided to place the temperature sensor in the middle at 1/4 of the rod length, which is optimal for the retrieval process and which is also coincident with the one chosen for HABIT and REMS. The measurements in the laboratory are providing good and constant temperature profiles with the chosen setup which correspond with the one expected from the equations that describe the heat transfer problem in a long rod. On the other hand, it is not possible to calculate a valid ambient temperature for the short rods, which is because of an overheated boundary layer around the rods due to the heating. For this reason, it is recommended to use the longest rod in the lab. For outside testing the influence of the Sun could be confirmed and was affecting the measurements of the copper rod. During the time span where the prototype was in the Sun, it was not possible to get any reasonable results. The next measurement campaign was defined in a shadowed area with diffuse light only. Finally, the tests of exposure to dynamic changes over time are in excellent agreement with the ones provided by the HOBO station and can even give a better resolution and sensitivity to small changes of wind magnitude. This prototype has confirmed experimentally, that under Earth conditions, this method can be used to retrieve the wind speed. Finally, the Martian data of the REMS ATS are analyzed and the comparisons suggest that the method is sensitive to wind changes on Mars as well, and shows better time and magnitude resolution than the existing REMS wind sensor. This confirms that this method can be successfully used for the HABIT sensor. In this work the methodology that shall be used on HABIT to retrieve the convective heat transfer and wind on the surface of Mars is validated for Earth outdoors conditions. It is recommended to verify the obtained results with tests in a wind tunnel and to see how the system will behave with a higher heating and different rod materials. Furthermore, the setup should be tested in a way which makes it possible to determine the different directions of the wind.

Yeung, Him Ching = 以粉末混合方法及夾心樣品方法製作的硼化鎂的特性研究 / 楊謙靖. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references. / Abstracts in English and Chinese. / Yeung, Him Ching = Yi fen mo hun he fang fa ji jia xin yang pin fang fa zhi zuo de peng hua mei de te xing yan jiu / Yang Qianjing. / Abstract --- p.i / 摘要 --- p.iii / Acknowledgments --- p.v / Table of contents --- p.vi / List of table captions --- p.viii / List of figure captions --- p.ix / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Superconductors --- p.1 / Chapter 1.1.1 --- Classifications --- p.1 / Chapter 1.1.2 --- Conventional versus unconventional --- p.2 / Chapter 1.1.3 --- Type I and Type II superconductors --- p.4 / Chapter 1.1.4 --- Critical current Jc and the Bean´ةs Model --- p.5 / Chapter 1.2 --- Magnesium diboride --- p.8 / Chapter 1.2.1 --- Structure --- p.8 / Chapter 1.2.2 --- Physical properties --- p.8 / Chapter 1.2.3 --- Chemical properties --- p.9 / Chapter 1.2.4 --- Conduction mechanisms --- p.9 / Chapter 1.2.5 --- Fabrication methods --- p.9 / Chapter 1.3 --- Objectives of this work --- p.10 / References --- p.12 / Figures --- p.14 / Chapter Chapter 2 --- Methodology and instrumentation --- p.17 / Chapter 2.1 --- Experimental procedures --- p.17 / Chapter 2.2 --- Samples preparation --- p.17 / Chapter 2.2.1 --- Powder mixing approach --- p.17 / Chapter 2.2.2 --- Sandwich structure approach --- p.18 / Chapter 2.3 --- Samples fabrication --- p.18 / Chapter 2.4 --- Determination of compositions --- p.18 / Chapter 2.5 --- Characterization --- p.19 / Chapter 2.5.1 --- X-ray diffractometry (XRD) --- p.19 / Chapter 2.5.2 --- Microstructural analysis --- p.20 / Chapter 2.5.3 --- Magnetic measurements --- p.20 / Chapter 2.5.3.1 --- Setup for Jc measurements --- p.21 / Reference --- p.22 / Figures --- p.23 / Chapter Chapter 3 --- Powder mixing approach --- p.26 / Chapter 3.1 --- Results --- p.26 / Chapter 3.1.1 --- XRD results --- p.26 / Chapter 3.1.2 --- Compositions --- p.27 / Chapter 3.1.3 --- SEM results --- p.28 / Chapter 3.1.3.1 --- Sample sintered at 600°C --- p.28 / Chapter 3.1.3.2 --- Samples sintered at 700°C and 800°C --- p.28 / Chapter 3.1.3.3 --- Sample sintered at 900°C --- p.29 / Chapter 3.1.3.4 --- Sample sintered at 1000°C --- p.29 / Chapter 3.1.3.5 --- Sample sintered at 1050°C --- p.29 / Chapter 3.1.4 --- VSM results --- p.30 / Chapter 3.1.4.1 --- Tc measurements --- p.30 / Chapter 3.1.4.2 --- Hysteresis loops --- p.31 / Chapter 3.1.5 --- Jc measurements --- p.31 / Chapter 3.1.5.1 --- Direct measurement --- p.31 / Chapter 3.1.5.2 --- The Bean´ةs Model --- p.32 / Chapter 3.2 --- Discussions --- p.32 / Chapter 3.3 --- Summary --- p.35 / References --- p.36 / Figures --- p.37 / Tables --- p.47 / Chapter Chapter 4 --- Sandwich structure approach --- p.49 / Chapter 4.1 --- Results --- p.49 / Chapter 4.1.1 --- SEM results --- p.49 / Chapter 4.1.1.1 --- Surface of the Mg disk --- p.49 / Chapter 4.1.1.2 --- Inner region of the Mg disk --- p.50 / Chapter 4.1.2 --- XRD results --- p.50 / Chapter 4.1.2.1 --- Surface of the Mg disk --- p.50 / Chapter 4.1.2.2 --- Inner region of the Mg disk --- p.51 / Chapter 4.1.3 --- VSM results --- p.51 / Chapter 4.1.3.1 --- Tc measurement --- p.51 / Chapter 4.1.3.2 --- Hysteresis loops --- p.52 / Chapter 4.2 --- Discussions --- p.52 / Chapter 4.3 --- Summary --- p.54 / Reference --- p.54 / Figures --- p.55 / Tables --- p.61 / Chapter Chapter 5 --- Growth Mechanism --- p.62 / Chapter 5.1 --- Introduction --- p.62 / Chapter 5.2 --- Brief summary of results --- p.62 / Chapter 5.2.1 --- Powder mixing approach --- p.62 / Chapter 5.2.2 --- Sandwich structure approach --- p.63 / Chapter 5.3 --- Formation of the MgB2 platelets --- p.63 / Chapter 5.4 --- Size of the MgB2 platelets --- p.67 / Chapter 5.5 --- Summary --- p.68 / References --- p.69 / Figures --- p.70 / Tables --- p.75 / Chapter Chapter 6 --- Conclusions and suggestions of future work --- p.76 / Chapter 6.1 --- Summary --- p.76 / Chapter 6.2 --- Future work --- p.77 / Appendix 1 --- p.79 / Appendix 2 --- p.81

This research concerns the effects on samples of nominal composition Bil.8Pb0.2Sr2Ca2cu30y which were exposed to hot, dense argon in a ballistic compressor. The investigations were concentrated on two specimens which were exposed to hot, dense argon at about 1800 K (peak pressure 330 atm) and 1500 K (peak pressure 230 atm), respectively. Sample Bi #1 showed a completely melted surface structure after triple exposure in the ballistic compressor at 1800 K while the surface of sample Bi #7 was just partly melted after double exposure at 1500 K. Changes in flux trapping capability and qualitative Meissner effect were investigated in addition to the properties described by Duan, et al. ( 17, 18, 3 2] , who reported changes in critical temperature, crystal structure, surface morphology and composition after exposure of samples to hot, dense argon. After triple exposure in the ballistic compressor at a temperature of approximately 1800 K, sample Bi #1 showed an enhanced Meissner effect on the exposed side compared to the unexposed side of the pellet, while no difference in Meissner effect was found between the exposed and the unexposed side of sample Bi #7. EDS analysis showed that both samples are inhomogeneous in chemical surface composition. Oxygen loss due to exposure to hot, dense argon could not be demonstrated. X-ray analysis indicated that the melted surface layer of sample Bi # 1 after triple exposure to hot, dense argon contains smaller crystals than before exposure in the ballistic compressor. Tc measurements gave varying results which are explainable by the chemical inhomogeneity of the specimens. An increase in the amount of trapped flux due to exposure of the samples to hot, dense argon could not be demonstrated

Water moves in soil in response to potential gradients. The basic equation for this movement is the generalized flow equation: v = - KV0 in which v is volume of water passing through a unit area in unit time, K is the conductivity coefficient, V is the gradient operator (vector), and V 0 is the potential gradient.

Remote sensing of land surface temperature (LST) is a complex task. From a satellite-based perspective the radiative properties of the land surface and the atmosphere are inextricably linked. Knowledge of both is required if one is to accurately measure the temperature of the land surface from a space-borne platform. In practice, most satellite-based sensors designed to measure LST over the surface of the Earth are polar orbiting. They scan swaths of the order of 2000 km, utilizing zenith angles of observation of up to 60°. As such, satellite viewing geometry is important when comparing estimates of LST between different overpasses of the same point on the Earth's surface. In the case of the atmosphere, the optical path length through which the surfaceleaving radiance propagates increases with increasing zenith angle of observation. A longer optical path may in turn alter the relative contributions which molecular absorption and emission processes make to the radiance measured at the satellite sensor. A means of estimating the magnitudes of these radiative components in relation to the viewing geometry of the satellite needs to be developed if their impacts on the at-sensor radiance are to be accurately accounted for. The problem of accurately describing radiative transfer between the surface and the satellite sensor is further complicated by the fact that the surface-leaving radiance itself may also vary with sensor viewing geometry. Physical properties of the surface such as emissivity are known to vary as the zenith angle of observation changes. The proportions of sunlit and shaded areas with the field-of-view of the sensor may also change with viewing geometry depending on the type of cover (eg vegetation), further impacting the surface emissivity. / Investigation of the change in surface-leaving radiance as the zenith angle of observation varies is then also important in developing a better understanding of the radiative interaction between the land surface and the atmosphere. The work in this study investigates the atmospheric impacts using surface brightness temperature measurements from the ATSR-2 satellite sensor in combination with atmospheric profile data from radiosondes and estimates of the downwelling sky radiance made by a ground-based radiometer. A line-by-line radiative transfer model is used to model the angular impacts of the atmosphere upon the surfaceleaving radiance. Results from the modelling work show that if the magnitude of the upwelling and downwelling sky radiance and atmospheric transmittance are accurately known then the surface-emitted radiance and hence the LST may be retrieved with negligible error. Guided by the outcomes of the modelling work an atmospheric correction term is derived which accounts for absorption and emission by the atmosphere, and is based on the viewing geometry of the satellite sensor and atmospheric properties characteristic of a semi-arid field site near Alice Springs in the Northern Territory (Central Australia). Ground-based angular measurements of surface brightness temperature made by a scanning, self calibrating radiometer situated at this field site are then used to investigate how the surface-leaving radiance varies over a range of zenith angles comparable to that of the ATSR-2 satellite sensor. / Well defined cycles in the angular dependence of surface brightness temperature were observed on both diumal and seasonal timescales in these data. The observed cycles in surface brightness temperature are explained in terms of the interaction between the downwelling sky radiance and the angular dependence of the surface emissivity. The angular surface brightness temperature and surface emissivity information is then applied to derive an LST estimate of high accuracy (approx. 1 K at night and 1-2 K during the day), suitable for the validation of satellite-derived LST measurements. Finally, the atmospheric and land surface components of this work are combined to describe surface-atmosphere interaction at the field site. Algorithms are derived for the satellite retrieval of LST for the nadir and forward viewing geometries of the ATSR-2 sensor, based upon the cycles in the angular dependence of surface brightness temperature observed in situ and the atmospheric correction term developed from the modelling of radiative transfer in the atmosphere. A qualitative assessment of the performance of these algorithms indicates they may obtain comparable accuracy to existing dual angle algorithms (approx. 1.5 K) in the ideal case and an accuracy of 3-4 K in practice, which is limited by knowledge of atmospheric properties (eg downwelling sky radiance and atmospheric transmittance), and the surface emissivity. There are, however, strong prospects of enhanced performance given better estimates of these physical quantities, and if coefficients within the retrieval algorithms are determined over a wider range of observation zenith angles in the future.

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

Thesis (Ph.D.)--Rochester Institute of Technology, 2007. / Typescript. Includes bibliographical references (p. [166]-171).

Graduation date: 1968

The WET-Temp (Watershed Evaluation Tool Temperature) model is designed to take advantage of spatially explicit datasets to predict stream temperature distribution. Datasets describing vegetation cover, stream network locations, elevation and stream discharge are utilized by WET-Temp to quantify geometric relationships between the sun, stream channel and riparian areas. These relationships are used to estimate the energy gained or lost by the stream via various heat flux processes (solar and longwave radiation, evaporation, convection and advection). The sum of these processes is expressed as a differential energy balance equation applied at discrete locations across the stream network. The model describes diurnal temperature dynamics at each of these locations and thus temperature distribution across the entire network. WET-Temp is calibrated to a tributary of the South Santiam River in western Oregon, McDowell Creek. The mean differences between measured and modeled values in McDowell Creek were 0.6��C for daily maximum temperature and 1.3��C for daily minimum temperature. The model was then used to predict maximum and minimum temperatures in an adjacent tributary, Hamilton Creek. The mean differences between modeled and measured values in this paired basin were 1.8��C for daily maximum temperatures and 1.4��C for daily minimum temperatures. Influences of model parameters on modeled temperature distributions are explored in a sensitivity analysis. The ability of WET-Temp to utilize spatially explicit datasets in estimating temperature distributions across stream networks advances the state of the art in modeling stream temperature. / Graduation date: 2003

The focus of this study is to examine the mechanisms involved in the interactions among large-scale atmospheric circulation patterns and how they are related to surface air temperature anomalies in the North American Arctic. Historical temperature data sets of Fairbanks, Alaska and Montreal, Quebec have been analyzed with respect to large-scale atmospheric circulation index data sets to investigate surface temperature anomalies in winter during the period 1960 to 2002.