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This is the first systematic report on the synthesis of mechanically alloyed Fe-Ni powders ball milled at liquid nitrogen temperature. Pure Fe-Ni samples were ball milled in a SPEX 8000 shaker mill at liquid nitrogen temperature. X-ray diffractometry was used to determine the phase fractions of the bcc and fcc phases in the alloys and to determine the lattice parameters and crystallite size. The main objective of this project is to study how the milling at low temperatures affects the region of two phase co-existence, phase structure and crystallite size. It was found that the composition ranges of the bcc and fcc single phase regions were extended well beyond the equilibrium ranges. The results obtained for the samples ball milled at liquid nitrogen temperature were compared to the previous samples ball milled at room temperature.

Svensk dramadialog under tre sekel är ett projekt framtaget vid Uppsala universitet och innehåller en dramakorpus av 45 pjäser från 1725–2000. Syftet med den här undersökningen är att undersöka utvecklingen av tilltal i fyra pjäser med utgångspunkt i fyra dramer ur Svensk dramadialog under tre sekel. Undersökningen har sin utgångspunkt i tilltalen du och Ni men andra tilltal som exempelvis titlar, förekommer. Undersökningen visar att samtidens tendenser för tillatalsbruk speglas i de fyra pjäserna mellan 1925 och 1997 och att miljöer och sociala förhållandena avgör vilket tilltal som används. Undersökningen visar även att författarna till dessa pjäser har möjlighet att använda tilltalet som en stilistisk resurs för att visa relationer mellan personer inom pjäsen. Undersökningen speglar även du-reformen och en utveckling av ett artigt nyniande som ersatt Ni.

Zirconium base alloys have very good metallic glass forming ability. In this study,the Zr-Cu-Ni ternary isotherm at 800¢J were determined by using metallography,electron-probe microanalysis and X-ray diffraction.The main objective is to provide the necessary information for alloy design to form new Zr-base with better glass forming ability.

This thesis is divided into two parts. The main purpose of the first part is only to confirm further whether adding B can really improve the glass forming ability (GFA) and thermal stability. It is recently suggested that the addition of the even smaller sized B (0.08 nm) in the Mg65Cu25Y10 alloys to a certain level can further enhance GFA and provide the chance in fabricating larger bulk amorphous billet. The current study extends the concept of adding B to the Mg65Ni25Y10 based alloy, including the replacement of Ni by 1-5 at % (1, 3, and 5 at %) using the arc melting and melt spinning methods. The second part, this experiment drops magnesium element to 58 at% boldly, even lower, and the big element atom neodymium (Nd) improves to 11 at% or more upwards, different from everybody commonly used 65 at %, 25 at % , 10 at % as the main proportion composition , then to observe whether its supercooled liquid region

Previous research studies have shown that teacher’s attitude towards girls and boys rather reinforces, than counteracts behavior as stereotyped gender concepts. Order and discipline seem to be important parts of the daily routines in school context and to maintain discipline a constant communication and dealing with pupils are in order. The purpose of our examination aims to study how teachers respond to boys and girls in situations like creation of order. The analysis is based on observations of the interaction that takes place verbally and none verbally between pupils and their teachers in creation of order situations. Using the materials we have found in our observations, we have been able to highlight how teachers treat boys and girls specifically in situations to create order. We have used a hermeneutic approach in our analysis and finally we tied the bag by discussing our results.

The deal of this thesis is study of the influence of LiOH added to electrolyte on Ni-Cd batteries. In theoretical part are analyzed properties of Ni-Cd accumulators in strong alkaline surroundings, especially with emphasis on structure changing of NiOH2 and NiOOH. In the second part of theoretical are also described methods for depositing Ni layers. In practical part electro-chemical spectrum and mass changing on Quartz crystal microbalance are measured by cyclic voltammetry method during charge/discharge process. The process of cation integration to the positive electrode structure in KOH, NaOH and CsOH electrolyte including related structural changes are observed.

As the global energy crisis and environmental pollution problem continues, there is an increasing demand for clean and sustainable energy storage and conversion technologies, such as water-splitting electrolysis. Water electrolysis is a process of running an electrical current through water in separating the hydrogen and oxygen. Oxygen evolution reaction (OER) is a key reaction in this electrochemical process, and the electrochemical performance of these systems is usually hindered by the slow OER reaction kinetics. In order to achieve high energy conversion efficiency, the development of efficient OER catalysts is the key. To achieve that, abundant research is done by using noble metal oxides as catalyst, such as IrO2 and RuO2. However, considering their high cost, a cheap earth-abundant material with a high OER catalytic activity is required. Accordingly, this study has been focused on the synthesis of three dimensional porous structured Ni-based OER catalysts. First, a 3D porous Ni meso-foam was developed through a facile high-temperature one-pot synthesis method, and its catalytic activity towards OER was explored. Specifically, the as-synthesized Ni meso-foam material, referred to as raw NMF, has a wire-linked structure and high surface area. A reduction procedure was introduced to obtain reduced Ni meso-foam materials, referred to as NMF-H2. It was also oxidized in air at 600 ℃ to form a semi-hollow NiO crosslinking phase and subsequently reduced in H2 at 300℃, forming a regenerated porous Ni foam material, referred to as NMF-O2/H2. The composition and morphology of all materials were investigated by XRD and SEM, respectively. The SEM image reveals that, in the porous NMF-O2/H2, the cross-linked meso-wire structure was maintained, and the average pore size is between 0.5-5 μm. Electrochemical analysis show that the OER activity of the Ni foam catalysts follows NMF-O2/H2 > NMF-H2 > raw NMF. In addition to the NMF-based materials, a Ni/Ni(OH)2 layer-structured electrocatalyst, referred to as NiDHBT, was also developed using a dynamic hydrogen bubble templating (DHBT) method. First, the 3D-porous micro Ni/Zn nanoplatelets were constructed in a two-step DHBT deposition method. The Ni/Zn foil was used as a scaffold, featured with the open porous structure and high surface area, for the subsequent electrodeposition of Ni(OH)2. Then, the Zn was etched from the as-prepared Ni/Zn/Ni(OH)2 nanocomposite to obtain the NiDHBT. The catalytic performance of the NiDHBT toward OER reaction was evaluated, and the optimal catalysts developed from different electro deposition potentials were determined. On the recognition of the high catalytic activity of NMF-O2/H2 and NiDHBT, porous structured FeOx-Nickel meso-foam, referred to as Fe@NMF-O2/H2, and FeOx- Ni/Ni(OH)2 layered-structure materials, referred to as Fe@NiDHBT, was further developed to explore the benefits of FeOx deposition for its OER catalytic performance. The deposition of FeOx is achieved by physical mixing FeOx colloid with NMF-O2/H2 and NiDHBT, and the electrochemical performance of these materials was examined in 1 M KOH. Among the developed materials, the best performing catalyst is Fe@NiDHBT synthesized by loading FeOx colloid onto the NiDHBT support. The overpotential for Fe@NiDHBT to reach 10 mA·cm-2 is 247mV, and the corresponding Tafel slope is 48.10mV·dec-1. Therefore, it was concluded that the FeOx¬¬ loading modification is an effective strategy to improve the OER activity of Ni foam-based catalysts.

Dans ce travail de thèse on étudie le développement de revêtements monocouches (simple couche) et multicouches à base de nickel en utilisant des techniques humides (électrodéposition et dépôt chimique dynamique). L'objectif principal est d'obtenir un revêtement d'une dureté élevée (supérieure à 500 HV) et une bonne résistance à la corrosion (plus de 500 heures en brouillard salin), sur la base des exigences de l'industrie aéronautique, principalement le groupe SAFRAN. Dans la première partie nous présentons le développement de revêtements de Ni par la technique d'électrodéposition. À partir d’un bain électrolytique de sulfamate avec différentes concentrations de samarium, nous avons obtenu un revêtement avec une résistance à la corrosion élevée. L'utilisation d'un bain électrolytique avec un additif de diméthyle amine borane (DMAB) conduit à un revêtement avec une dureté élevée. Ainsi, nous avons prépare un revêtement multicouche acier/Ni (Sm)/Ni-B, pour obtenir un dépôt avec bonne résistance à la corrosion (proportionné par la couche de Ni électrolytique obtenu à partir d’un bain avec samarium) et une dureté élevée (proportionné pour la couche Ni-B électrolytique). En outre, en employant la technique de dépôt chimique dynamique (JetMetal) on a obtenu un revêtement de Ni-B ayant une dureté élevée et un revêtement composite de Ni-B-PTFE avec de bonnes propriétés tribologiques. Finalement nous avons élaboré un revêtement multicouche acier /Ni (Sm)/NiB-SDS/NiBPTFE à partir des technologies de dépôt électrochimique et la technique JetMetal, le revêtement obtenu présente une bonne résistance à la corrosion, une dureté élevée et un faible coefficient de frottement. / In this thesis work we investigate the development of monolayer coatings (single layer) and nickel-based multilayers by using wet techniques (electrodeposition and dynamic chemical deposition). The main objective is to obtain a coating with high hardness (above 500 HV) and good corrosion resistance (over 500 hours in salt spray), based on the requirements of the aviation industry, mainly the SAFRAN group. The first part of this thesis examines the development of Ni coatings by using electrodeposition technique. From an electrolytic sulfamate bath with different samarium concentrations, can be obtained coatings with high resistance to corrosion, while the use of an electrolytic bath with dimethyl amine borane (DMAB) leads to a coating with high hardness. The development of multilayer coatings in an alternated way using two electrolytic baths (with different composition), was realized to take advantage of the individual properties of each deposit. Thus the steel/Ni (Sm)/Ni-B multilayer coating was obtained, in order to be use the good corrosion resistance of Ni layer obtained from a bath with samarium and the high hardness of a Ni-B coating. On the other hand, by employing the dynamic chemical deposition technique (JetMetal), Ni-B coating with high hardness and a composite coating Ni-B-PTFE with good tribological properties could be obtained. Finally, a multilayer coated steel/Ni(Sm)/NiB-SDS/NiB-PTFE was developed by combining the electroplating technology and dynamic chemical deposition technique, the obtained coating showed good corrosion resistance, high hardness and a low friction coefficient. / En este trabajo de tesis se investiga la elaboración de recubrimientos monocapa (una sola capa) y multicapas a base de níquel mediante el empleo de técnicas vía húmeda (electrodepósito y depósito químico dinámico). El objetivo principal es de obtener un recubrimiento con alta dureza (superior a 500 HV) y buena resistencia a la corrosión (superior a 500 h en cámara salina), en base a los requerimientos de la industria aeronáutica, principalmente el grupo SAFRAN. En la primera parte de esta tesis se estudia la elaboración de recubrimientos de Ni mediante el empleo de la técnica de electrodepósito. A partir de un baño electrolítico de sulfamato con diferente concentración de samario, se puede obtener un recubrimiento con alta resistencia a la corrosión. En tanto que el uso de un baño electrolítico con el aditivo dimetil amina borano (DMAB) permite obtener un recubrimiento con alta dureza. La elaboración de recubrimientos multicapas mediante el uso alternado de dos baños electrolíticos de composiciones diferentes, permite aprovechar las propiedades individuales de cada depósito. Así se elaboró un recubrimiento multicapa acero/Ni(Sm)/Ni-B, para aprovechar la buena resistencia a la corrosión de una capa de Ni obtenida a partir de un baño con samario y la dureza elevada de un recubrimiento Ni- B. Por otra parte, mediante el empleo de la técnica de depósito químico dinámico (JetMetal) fue posible obtener recubrimiento Ni-B con alta dureza y un recubrimiento compuesto Ni-B-PTFE con buenas propiedades tribológicas. Finalmente se elaboró un recubrimiento multicapa acero/Ni(Sm)/NiB-SDS/NiB-PTFE mediante el empleo combinado de la técnica de electrodepósito y la técnica de depósito químico dinámico, que presenta una muy alta resistencia a la corrosión, una alta dureza y un bajo coeficiente de fricción.

Sustainable energy sources are of great importance, and will become even more important in the future. Gasification of biomass is an important process for utilization of biomass, as a renewable energy carrier, to produce fuels and chemicals. Density functional theory (DFT) calculations were used to investigate i) the effect of co-adsorption of water and CO on the Ni(111) catalysed water splitting reaction, ii) water adsorption and dissociation on Ni(111), Ni(100) and Ni(110) surfaces, as well as iii) formyl oxidation and dissociation, iv) hydrocarbon combustion and synthesis, and v) the water gas shift (WGS) reaction on these surfaces. The results show that the structures of an adsorbed water molecule and its splitting transition state are significantly changed by co-adsorption of a CO molecule on the Ni(111) surface. This leads to less exothermic reaction energy and larger activation barrier in the presence of CO which means that far fewer water molecules will dissociate in the presence of CO. For the adsorption and dissociation of water on different Ni surfaces, the binding energies for H2O and OH decrease in the order Ni(110) > Ni(100) > Ni(111), and the binding energies for O and H atoms decrease in the order Ni(100) > Ni(111) > Ni(110). In total, the complete water dissociation reaction rate decreases in the order Ni(110) > Ni(100) > Ni(111). The reaction rates for both formyl dissociation to CH + O and to CO + H decrease in the order Ni(110) > Ni(111) > Ni(100). However, the dissociation to CO + H is kinetically favoured. The oxidation of formyl has the lowest activation energy on the Ni(111) surface. For combustion and synthesis of hydrocarbons, the Ni(110) surface shows a better catalytic activity for hydrocarbon combustion compared to the other surfaces. Calculations show that Ni is a better catalyst for the combustion reaction compared to the hydrocarbon synthesis, where the reaction rate constants are small. It was found that the WGS reaction occurs mainly via the direct pathway with the CO + O → CO2 reaction as the rate limiting step on all three surfaces. The activation barrier obtained for this rate limiting step decreases in the order Ni(110) > Ni(111) > Ni(100). Thus, the WGS reaction is fastest on the Ni(100) surface if O species are present on the surfaces. However, the barrier for desorption of water (as the source of the O species) is lower than its dissociation reaction on the Ni(111) and Ni(100) surfaces, but not on the Ni(110) surface. Therefore the direct pathway on the Ni(110) surface will dominate and will be the rate limiting step at low H2O(g) pressures. The calculations also reveal that the WGS reaction does not primarily occur via the formate pathway, since this species is a stable intermediate on all surfaces. All reactions studied in this work support the Brønsted-Evans-Polanyi (BEP) principles.