Aluminized steel Type 2 (AST2), often used for culvert pipes, is subject to corrosion which is the most important durability limitation factor. It was desired to determine if the outer aluminized layer will retain passivity and if protective galvanic action will develop. Thus, corrosion of unblemished and blemished AST2 surfaces was investigated in simulated natural waters. Experiments with unblemished specimens showed passive corrosion rates (~0.06 µm/yr) in scale-forming, 0.01 M Cl- solutions but sustained corrosion in other less protective media (with rates 3~10 µm/yr). Corrosion was manifested macroscopically by discoloration and few macro pits, but it likely proceeded also microscopically at the Fe-rich inclusion space scale. For blemished specimens, the aluminized coating galvanically protected to some extent the steel in all solutions. However, in 0.01 M Cl- solutions, protection was delayed until after some steel corrosion had occurred. In some solutions, complete consumption of the outer aluminized coating around exposed steel was noted. Elsewhere, coating appearance was similar to that of the unblemished condition. Nominal durability projections made for 16-gage AST2 ranged from >100 yr for unblemished AST2 to ~10 yr for the blemished condition. The present findings were used as a first step in proposing refinements of presently used durability guidelines of AST2 culvert pipe. Cyclic cathodic polarization tests to examine O2 and H2 reduction at the Fe-rich inclusions showed significant hysteresis, more pronounced with decreasing scan rate. The effect was tentatively associated to the amount of Fe+2 being deposited during the downward scan, a hypothesis supported by results from a physical model. A static polarization model was formulated for the blemished configuration. Results matched experimental trends and permitted evaluating the effect of solution conductivity s beyond the experimental range. Exposed steel corrosion rates at the steel were increasingly large for decreasing s. For the lowest s, corrosion rates at the exposed steel center were distinctly larger than at the edge, consistent with experiments. An impedance behavior model was also formulated. Results showed frequency dependent current distribution and predicted relatively small artifacts that were and not evident experimentally, but should be considered when exploring other system conditions.

High energy density batteries have garnered much attention in recent years due to their demand in electric vehicles. Lithium-oxygen (Li-O2) batteries are becoming some of the most promising energy storage and conversion technologies due to their ultra-high energy density. They are still in the infancy stage of development and there are many challenges needing to be overcome before their practical commercial application. Some of these challenges include low round-trip efficiency, lower than theoretical capacity, and poor rechargeability. Most of these issued stem from the poor catalytic performance of the cathode that leads to a high overpotential of the battery. In this doctoral work, Li-O2 cathodes containing nanoparticles of palladium were used to alleviate this problem. Cathodes composed of palladium-coated and palladium-filled carbon nanotubes (CNTs) were prepared and investigated for their battery performance. The full discharge of batteries showed 6-fold increase in the first discharge of the Pdfilled over the pristine CNTs and 35% increase over their Pd-coated counterparts. The Pd-filled CNTs also exhibited improved cyclability with 58 full cycles of 500 mAh·g-1 at current density of 250 mA·g-1 versus 35 and 43 cycles for pristine and Pd-coated CNTs, respectively. The effect of encapsulating the Pd catalysts inside the CNTs proved to increase the stability of the electrolyte during both discharging and charging. Voltammetry, Raman spectroscopy, XRD, UV/Vis spectroscopy, and visual inspection of the discharge products using scanning electron microscopy confirmed the increased stability of the electrolyte due catalyst shielding. The electrochemical oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) on carbon nanotubes (CNT) cathodes with palladium (Pd) catalyst, Pd-coated CNT and Pd-filled CNT, have been evaluated in an ether-based electrolyte solution to develop a lithium oxygen (Li−O2) battery with a high specific energy. The electrochemical properties of CNT cathodes were studied using electrochemical impedance spectroscopy (EIS). The infrared spectroscopy and SEM are employed to analyze the reaction products adsorbed on the electrode surface of the Li-O2 battery developed using Pd-coated and Pd-filled CNTs as cathode and an ether based electrolyte. vii Studies in this dissertation conclude that the use of nanocatalysts composed of palladium improved the overall performance of the Li-O2 batteries, while shielding these catalysts from direct contact with the electrolyte prolonged the life of the battery by stabilizing the electrolyte.

This study focused on measuring the importance and contribution of information obtained from the library, particularly electronic information services (EIS), to success in solving clinical problems in hospitals. Three research questions with three main hypotheses were advanced and tested on clinicians in 44 hospitals in Hong Kong. The findings were tested against the framework from Wilson's (1996) existing general information behaviour model, from which a new extended model for clinicians was built. Measures of EIS were then derived from the new model. The research was broadly divided into a series of five studies in two stages: nominal group, quantitative survey, and interviews in the first stage, and randomized controlled study as well as the analyses of statistical data and computer transaction logs in the second stage. The key results in Stage I led to the studies in Stage 11. The randomized controlled study in Stage 11 attempted to reduce the barriers identified in the information environment, with a view to test the results of an educational intervention, and to confirm that the hypotheses were true given reduced barriers and the presence of enabling conditions. The effects of the interventions in this experimental study were validated and verified by statistical data and transaction logs. Corroborative evidence from the two-stage studies showed that the three main inter-connected hypotheses were supported: success in problem-solving is related to the information sources used; user satisfaction is related to success in problem-solving; and EIS use is an indicator of user satisfaction. EIS use is determined by a number of factors: the preference for EIS, the use of the library, the skills and knowledge in searching, the profession of the user and the characteristics of the work environment. Educational intervention was found to improve success in problem-solving, the attitudes, skills and knowledge in searching, the satisfaction with and use of EIS, and is an important enabling condition. The research rejected part of the first hypothesis posed that success in problem-solving is related to clinical question posed and suggests that further research is needed in this area. The study supported the extension of the general model to clinical information needs and behaviours and found new relationships. The study found an additional determinant of EIS satisfaction, the satisfaction with the information obtained. EIS satisfaction would not be changed by educational intervention alone if the information obtained was not satisfactory. On the other hand, education can improve EIS satisfaction regardless of whether the problem has been solved. Of critical importance is the time factor in determining the use (or non-use) of EIS. There is new evidence that the awareness of the user of an answer in literature is a determining factor for active searching. Borrowing the concept of opportunity cost from economic theory, the researcher relates it with the differing levels of self-efficacy and postulates a model for planning EIS and related library services. From the new extended model of information behaviour, sixteen main measures or indicators were tested on a proposed framework in developing performance measures to diagnose information behaviours and predict EIS use, satisfaction and success in problem-solving. In measuring EIS, the researcher suggested the holistic approach in assessing traditional (non-electronic) library and information services as part of information behaviours of clinicians. The study pointed to the imbalance between self-efficacy and the actual skills and knowledge of users in their searching mentality and activities and the implication for library practice. Qualitative aspects that require further research on measurement were suggested. The study has important ramifications for theory and practice for the information professional. The new extended model of information behaviour for clinicians establishes deterministic relationships that help explain why an information search is pursued actively, continuously, or not at all. Measures that have been derived from these relationships can help diagnose and predict information behaviours. The study highlights the flexibility and utility of the general model of information behaviour. Also, this is the first time that such a methodological approach has been adopted to derive EIS measures. The application of the randomized controlled study methodology in information science was proven to be feasible and yielded definitive results. The researcher proposes that further development of information behaviour model should incorporate the element of knowledge generation process in an organization.

Ion-sensitive field effect transistors (ISFET's) have many advantages than the conventional ion selective electrodes. There exhibt the advantages of small size, fast response and compatible with conventional IC technologies. The general structure of ISFET is the same as that of MOSFET. However, the main difference is that the metal gate in MOSFET is replaced by reference electrode/electrolyte/sensing insulator structure in ISFET. The insulator surface will suffer the change of potential as the sample is immersed into electrolyte, by which, we can measure the pH or other ionic concentration. Amorphous barium titanate (a-BaTiO3) thin film as the pH-sensing layer of the ion-sensitive field-effect transistor is prepared by a sol-gel technique. The stock solution in a concentration about 0.42M is obtained. The barium titanate thin films are deposited on SiO2(1000Å)/p-Si substrates, and the EIS structure is frabricated. The fabrication parameters of BaTiO3 thin films are made up of the thickness of 120-360 nm and the firing temperature between 350¢J and 850¢J. The flat-band voltage(£GVBF) is shifted by C-V measurement. The pH sensitivity is on the downside because the thin films thickness and defect increase. The results reveal the MIS C-V curve. The optimum conditions are found that the annealing temperature is about 350¢J, and the sensitivity of about 59.02 mV/pH with regression of 0.9991. The pH response of 40-59 mV/pH in the range of pH 2-12 exists when the a-BaTiO3 thin film with thickness of about 120-360nm at the firing temperature between 350¢J and 550¢Jare prepared. To decrease the fabrication cost, so the numbers of mask and fabrication steps should be minimized, which are reduced to two from four and 10 from 16 steps. Two masks were used to accomplish a-BaTiO3 gated ISFET. I-V curve shows that the a-BaTiO3 gated ISFET exhibits pH responses of about 38 ~48.7 mV/pH in the linear region(IDS=30 £gA and VDS¡×0.2 V), and -11~-24.8 £gA/pH in the satiation region(VGS=3 V and VDS¡×3.5 V), and the regression of above 0.997 was achieved. Both of C-V and I-V curves revealed the BaTiO3 thin films could be used in the ISFET gate.

Une piqûre est généralement décrite comme étant une attaque concentrée sur une petite portion de surface, qui se propage en profondeur dans le métal et dont l'évolution reste très imprévisible. Les techniques électrochimiques "classiques" sont très utilisées pour étudier les problèmes liés à la corrosion localisée et ont permis de décrire le comportement global d'une électrode métallique sans cependant pouvoir décrire le développement d'une piqûre isolée. La finalité de cette étude est la compréhension de la corrosion par piqûre du Fer depuis l'étape d'initiation jusqu'à la phase de propagation ou de repassivation. Ce travail a donc concerné la mise en oeuvre de protocoles expérimentaux permettant d'étudier une piqûre unique. Pour y parvenir, le microscope électrochimique à balayage (SECM) a été utilisé pour la génération de la piqûre. Son évolution a pu être étudiée par des mesures de courants ou de potentiels ainsi que par d'autres techniques in situ couplées au SECM (spectroscopie d'impédance EIS, microbalance à quartz). Des techniques physiques d'analyse (microscope électronique à balayage, analyse Raman,...) ont également été utilisées pour caractériser a posteriori la piqûre et les produits de corrosion. Les résultats obtenus ont notamment permis de corréler différents paramètres expérimentaux avec l'initiation et la propagation de la piqûre. Les produits de corrosion ont pu être déterminés en fonction de la nature de l'électrolyte (acide, neutre ou basique). L'utilisation du couplage SECM / EQCM a permis la détermination du degré d'oxydation du Fer dissous et le couplage SECM / EIS a permis de caractériser l'évolution de la piqûre.

Les alliages d'aluminium utilisés dans l'industrie aérospatiale présentent une microstructure complexe en raison des traitements thermiques et mécaniques auxquels ils ont été soumis pour l'amélioration de leur dureté. La microstructure de ces alliages est caractérisée par la présence d'un grand nombre de particules intermétalliques (IM) dont l'activité électrochimique est différente de celle de la matrice environnante conduisant à l'apparition de phénomènes de corrosion localisée comme des cellules galvaniques. Au cours de ces dix dernières années, la spectroscopie d'impédance électrochimique locale (SIEL) a été utilisée comme un outil puissant pour mettre en évidence les caractéristiques locales associées à la corrosion ainsi qu'étudier les questions théoriques liées aux distributions de courant et potentiel à la surface des électrodes et leur corrélation avec la réactivité de surface. Cette approche est basée sur l'analyse des différentes impédances locales acquises par une bi-électrode placée au voisinage de la surface de l'électrode et sur la simulation de ces résultats. L'objectif de ce travail est d'étudier la corrosion localisée d'un alliage Al 7475-T761, utilisé, pour ses propriétés mécaniques, dans les ailes d'avion et le fuselage, dans les milieux contenant des ions sulfate au moyen de la spectroscopie d'impédance électrochimique (SIEL) et de la SIEL associés à la caractérisation microstructurale par MEB/EDS. Les résultats obtenus avec les techniques globales ainsi que la caractérisation microstructurale ont confirmé que le pH local augmente à l'interface matrice/IM en raison de la réaction cathodique sur les particules IM qui est la cause la plus importante de corrosion localisée de l'alliage. Ce processus conduit à la dissolution locale de la couche passive et à une dépolarisation importante de la réaction d'oxydation de l'aluminium conduisant à une forte augmentation de la vitesse de corrosion du métal. D'autre part, les études mettant en oeuvre l'électrode à disque tournant (RDE) ont révélées que les ions sulfate augmentent les performances anti corrosion de la couche passive et sont particulièrement agressifs à linterface IM/Cu. En ce qui concerne les études avec la technique SIEL, elles ont été effectuées en utilisant un couple modèle Al 7475/Cu afin de simuler la réactivité électrochimique de l'interface IM/alliage. A notre connaissance, cette approche est nouvelle car c'est la première fois qu'un alliage commercial a été utilisé comme l'un des composants d'un couple modèle pour des études électrochimiques locales. Les résultats obtenus sont conformes aux modèles théoriques déjà développés pour les effets induits par la géométrie sur les distributions de courant et de potentielle sur la réactivité de surface des électrodes. Il a également été montré que la bi-électrode est sensible à de petites variations de la réactivité électrochimique à l'interface du couple galvanique, ce qui a été confirmé par SEM / EDS. Une autre originalité de ce travail concernant la technique SIEL, est l'utilisation pour la première fois d'une tri-électrode acquérir les diagrammes d'impédance locale. Ce système permet la mesure simultanée des composantes normale et radiale de la densité de courant locale et rend possible une meilleure compréhension des phénomènes locaux interfaciaux. Les résultats des mesures avec ce nouveau système sont en bon accord avec le modèle théorique de la réponse électrochimique locale présenté dans ce travail, montrant ainsi que qu'il peut être un outil précieux pour une meilleure compréhension des processus électrochimiques locaux.

Companies financed through borrowed capital are allowed a tax deduction for the costs re-lated to their borrowed capital. A similar tax relief for companies financed through share-holder’s equity does not exist, why these companies are taxed higher than companies fi-nanced by borrowed capital. The result is that there is an asymmetric tax treatment of companies depending on how they are financed. The autumn of 2012, the Swedish government presents a proposal for an investor deduc-tion which seeks to equalize the above mentioned asymmetry. The proposed investor de-duction is a tax relief for investments in shares in a startup- or small company equal to 50 percent of the acquisition cost of that investment. The venture capital deduction, which in this thesis is treated as an alternative to the inves-tor deduction, is an interest-free tax credit which significate that two-thirds of the acquisi-tion cost is deductible from taxation at the time of the acquisition. Another alternative is the UK's Enterprise Investment Scheme (EIS), which offers a package of tax reliefs that becomes applicable when an individual invests in a company for example a tax credit of 30 percent of the cost of acquisition. A final option is the Notional Interest Deduction (NID) which is a tax deduction for companies regarding a fictitious interest on equity. Of these models, only the NID deduction equalizes the tax asymmetry, because of that it is a relief that is comparable to the tax credit deduction for interest on borrowed capital. However entails all models, except the venture capital deduction, to make external capital more accessible by reducing the external investor's required rate of return by allowing a permanent tax relief. Aside from the NID deduction all models includes conditions that reduces the risk of the use of the models for purpose of tax avoidance which results in that that models can be perceived as complex.

Ion-sensitive field effect transistors (ISFET's) have many advantages than the conventional ion selective electrode. Small size, fast response and compatible with conventional IC technologies were the most important advantages. The general structure of ISFET was the same with MOSFET, but the main difference is that the metal gate in MOSFET was replaced by reference electrode/electrolyte/insulator(ionic sensor membrane) structure in ISFET. The insulator surface will suffer the change of potential as the is sample immersed into electrolyte, by which, we can measure the pH or other ionic concentration. In this thesis the amorphous lead titanate (a-PbTiO3) thin film was prepared by sol-gel method to be the sensor gate of ISFET. The lead titanate thin films were deposited on SiO2(1000Å)/p-Si substrates, and the EIS structure was obtained. The flat-band voltage(£GVBF) can be shifted by C-V measurement. The optimum conditions were found that the firing temperature was about 4000C and thin film thickness was about 0.5

<p>In order to extend the applications of aluminium, organic coatings may be applied on sheet materials, for instance for corrosion protection or aesthetic surface finish purposes in the automotive and construction industries, or on foil materials in the flexible packaging industry.</p><p>The most common mechanisms for deterioration and structural failure of organically coated aluminium structures are triggered by exposures to the surrounding environment. Despite the great importance to elucidate the influence of exposure parameters on a buried aluminium/polymer interface, there is still a lack of knowledge regarding the mechanisms that destabilise the structure. It is generally believed that a detailed <i>in situ</i> analysis of the transport of corroding species to the buried interface, or of surface processes occurring therein, is most difficult to perform at relevant climatic and real-time conditions.</p><p>In this work, Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR) in the Kretschmann-ATR configuration was successfully applied to <i>in situ</i> studies of the transport of water and ionic species through polymer films to the aluminium/polymer interface upon exposure to ultra pure deionised water and to a 1 M sodium thiocyanate (NaSCN) model electrolyte. Other main processes distinguished were the formation of corrosion products on the aluminium surface and swelling of the surface-near polymer network. Hence, <i>in situ</i> ATR-FTIR was capable to separate deterioration-related processes from each other.</p><p>To perform more unambiguous interpretations, a spectro-electrochemical method was also developed for<i> in situ</i> studies of the buried aluminium/polymer interface by integrating the ATR-FTIR technique with a complementary acting technique, Electrical Impedance Spectroscopy (EIS). While transport of water and electrolyte through the polymer film to the aluminium/polymer interface and subsequent oxidation/corrosion of aluminium could be followed by ATR-FTIR, the protective properties of the polymer as well as of processes at the aluminium surface were simultaneously studied by EIS. The integrated set-up provided complementary information of the aluminium/polymer sample investigated, with ATR-FTIR being sensitive to the surface-near region and EIS being sensitive to the whole system. While oxidation/corrosion and delamination are difficult to distinguish by EIS, oxide formation could be confirmed by ATR-FTIR. Additionally, while delamination and polymer swelling may be difficult to separate with ATR-FTIR, EIS distinguished swelling of the polymer network and also identified ultimate failure as a result of delamination.</p><p>The capability of the integrated ATR-FTIR / EIS <i>in situ</i> technique was explored by studying aluminium/polymer systems of varying characteristics. Differences in water and electrolyte ingress could be monitored, as well as metal corrosion, polymer swelling and delamination.</p>

Environmental and economic reasons have lead automotive companies towards the direction of EVs and HEVs. Stricter emission legislations along with the consumer needs for more cost-efficient and environmental friendly vehicles have increased immensely the amount of hybrid and electric vehicles available in the market. It is essential though for Li-ion batteries, the main propulsion force of EVs and HEVs, to be able to read the battery characteristics in a high accuracy manner, predict life expectancy and behaviour and act accordingly. The following thesis constitutes a concept study of a battery diagnostics method. The method is based on the notion of a pseudo-random binary signal used as the current input and from its voltage response, the impedance is used for the estimation of parameters such as the state of charge and more. The feasibility of the PRBS method at a battery cell has been examined through various tests, both in an experimental manner at the lab but also in a simulation manner. The method is compared for validation against the electrochemical impedance spectroscopy method which is being used as a reference. For both the experimental and the simulation examinations, the PRBS method has been validated and proven to work. No matter the change in the parameters of the system, the method behaves in a similar manner as in the reference EIS method. The level of detail in the research and the performed experiments is what makes the significance of the results of high importance. The method in all ways has been proven to work in the concept study and based on the findings, if implemented on an EV’s or HEV’s electric drive line and the same functionality is observed, be used as a diagnostics method of the battery of the vehicle.