Объектом исследования являются электроды на основе нанотубулярного диоксида титана, модифицированные различными способами (термическая обработка, создание композитов с углеродными нанотрубками и частицами металлического никеля). Синтезированные образцы исследовались методом растровой электронной микроскопии и различными электрохимическими методами анализа (гальваностатический заряд-разряд, циклическая вольтамперометрия, импедансная спектроскопия). В результате исследования получены электроды: 1) Т/TiO2-НТ; 2) УНТ/TiO2-НТ; 3) Ni/TiO2-НТ представляющие собой: 1) массивы TiO2-НТ толщиной 3,5 мкм, с внутренним диаметром 70-80 нм и толщиной стенок 30-40 нм; 2) массивы TiO2-НТ с углеродными нанотрубками диаметром 10-30 нм и длиной от десятков нм до десятков мкм на поверхности оксидного слоя; 3) массивы TiO2-НТ, декорированные сферическими наночастицами Ni диаметром 70-100 нм с образованием локальных конгломератов частиц до 500 нм. Результаты работы позволили получить информацию об электрохимических характеристиках синтезированных электродов и преимуществах модификации структур TiO2-НТ для использования их в качестве электродов ионистров. / The object of this research is electrodes based on nanotubular titanium dioxide, modified by various methods (thermal treatment, synthesis of composites with carbon nanotubes and metallic nickel particles). The synthesized samples were investigated by scanning electron microscopy and various electrochemical analysis methods (galvanostatic charge-discharge, cyclic voltammetry, impedance spectroscopy). As a result of the study, were obtained: 1) T/TiO2-NT; 2) CNT/TiO2-NT; 3) Ni/TiO2-NT electrodes, which are: 1) arrays of TiO2-NT 3.5 μm thick, with an inner diameter of 70-80 nm and wall thickness 30-40 nm; 2) arrays of TiO2-NT with carbon nanotubes with a diameter of 10-30 nm and a length from tens of nm to tens of microns on the surface of the oxide layer; 3) arrays of TiO2-NT, decorated with spherical Ni nanoparticles with a diameter of 70-100 nm with the formation of local conglomerates of particles up to 500 nm. The results of the work made it possible to obtain information on the electrochemical characteristics of the synthesized electrodes and the advantages of modifying the TiO2-NT structures to use them as supercapacitor electrodes.

Grease is among the most widely used lubricants in rolling element bearings. Proper understanding of the effect of lubrication due to grease aging can provide a significant increase in the life of the engineering systems. However, at present, there is no sufficient understanding of the grease aging effect in rolling elements bearing. This restricts the optimal usage of the bearing and timely monitoring of the grease. The current research work tries to address this issue with an experimental investigation. This project studies the behavior of 4 types of greases in rolling elements bearings for various operating conditions by recording the temperature and acoustic emission data. The aged samples were prepared to keep in the oven at 150 °C for a series of time duration letting it go through the chemical changes and thermal degradation. Tests were carried out in a test rig with the different levels of oxidized greases for 5 hrs time. And the effects in bearing temperature, acoustic emission were recorded. This is an investigation to analyze the effects of grease composition and aging in rolling elements lubrication by means of acoustic emission and bearing temperature. The IR spectroscopy was carried from the samples collected from the oven in order to understand the change in lubricant composition. The results show that the grease with di-urea thickener and base oil of synthetic ether and polyolester gives the best bearing temperature and acoustic emission behavior compared to the other grease type. The possibility of using the acoustic emission and temperature data to monitor the grease aging is also presented. Along with this, the possibility of using the AE statistical methods, AE count method, and energy plot were also explored to relate with the degree of aging.

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Lithium-ion (Li-Ion) batteries are widely used in various applications and are viable for automotive applications. The effective management of Li-Ion batteries in battery electric vehicles (BEV) plays a crucial role in performance and range. One can achieve good performance and range by using efficient battery models in battery management systems (BMS). Hence, these battery models play an essential part in the development process of battery electric vehicles. Physics-based battery models are used for design purposes, control, or to predict battery behaviour, and these require much information about materials and reaction and mass transport properties. Model parameterization, i.e., obtaining model parameters from different experimental sets (by fitting the model to experimental data sets), can be challenging depending on model complexity and the type and quality of experimental data. Based on the idea of parameter sensitivity, certain current/voltage data sets could be chosen that theoretically has a more considerable sensitivity for a given model parameter that is of interest to extract. In this thesis work, different methods for extracting model parameters for a Nickel-Manganese-Cobalt (NMC) battery composite electrode are experimentally tested and compared. Specifically, model parameterization using \emph{optimal experiments} based on performed parameter sensitivity analysis has been benchmarked against a 1C discharge test and low rate pulse tests. The different parameter sets obtained have then been validated on a drive cycle and 2C pulse tests. Comparing the methods show some promising results for the optimal experiment design (OED) method, but consideration regarding the state of charge (SOC) dependencies, the number of parameters has to be further evaluated. / Litiumjonbatterier (Li-jon) används i olika applikationer och är ett bra alternativ förfordonsapplikationer. Den effektiva hanteringen av litiumjonbatterier i elbilar har en viktigroll för fordonens prestanda och räckvidd. Man kan nå bra prestanda och räckviddgenom att använda bra batterimodeller i batteriets övervakningssystem (BMS). Därförspelar dessa batterimodeller en viktig roll i utvecklingen av elbilar. Fysikbaseradebatterimodeller används för design, reglering eller för att prediktera beteendet hos batteriet,vilket kräver mycket information om material samt dess reaktion och andra beskaffenheter.Modellparametrisering, dvs. att införskaffa modellparametrar från olika experiment (genom attanpassa modell till experimentella data) kan vara utmanande beroende på modellkomplexitetoch typen samt kvalitén på experimentell data. Baserat på idén om parametersensitivitet kan data om ström och spänning väljas så att de teoretiskt har mer sensitivitet för engiven modellparameter som är av intresse att extrahera. I detta examensarbete testas ochjämförs olika metoder för att extrahera modellparametrar för en Nickelmangankobolt (NMC)batterielektrod. Mer specifikt, modellparametrisering genom optimala experiment baseradepå genomförd parametersesitivitetsanalys jämförts med 1C urladdningstest och låg nivåpulstest. Jämförande av metoderna visar goda resultat för OED metoden men flera parametrarmåste fortsatt utvärderas gällande laddningstatusberoenden (SOC).

Einzelschichten von Graphen-Nanobänders (GNRs) wurden auf SiC(0001)-Substraten mit zwei unterschiedlichen Fehlschnitten bei Temperaturen von 1410 bis 1460 °C synthetisiert. Das GNR-Wachstum lässt sich bei niedriger Stufenkantenhöhe am besten durch eine exponentielle Wachstumsrate, welche mit der Energiebarriere für die Ausdiffusion von Si korreliert ist. Anderseits wird bei Substraten mit höheren Stufenkanten eine nicht-exponentielle Rate beobachtet, was mit der Bildung von mehrlagigen Graphen an den Stufenkanten in Verbindung gebracht wird. Die Sauerstoffinterkalation von epitaktischen GNRs mittels Ausglühen an Luft von Bändern wird als nächstes untersucht, welche auf unterschiedlichen SiC-Substraten gewachsen wurden. Neben der Umwandlung von monolagigem zu zweilagigem Graphen in der Nähe der Stufenkanten von SiC, führt die Sauerstoffinterkalation zusätzlich zu der Bildung einer Oxidschicht auf den Terrassen des Substrats, was die zweilagigen GNRs elektrisch isoliert voneinander zurücklässt. Die elektrische Charakterisierung der zweilagigen GNRs zeigten dass die Bänder durch die Behandlung mit Sauerstoff elektrisch voneinander entkoppelt sind. Eine robuste Lochkonzentration von etwa 1x10¹³ cm-² und Mobilitäten von bis zu 700 cm²/(Vs) wurden für die GNRs mit einer typischen Breite von 100 nm bei Raumtemperatur gemessen. Wohl definierte Mesastrukturen gebildet mittels Elektronenstrahllithographie auf SiC-Substraten, wurde zuletzt untersucht. Die Charakterisierung des Ladungsträgertransports von GNRs die auf den Seitenwänden der strukturierten Terrassen gewachsen wurden, zeigt eine Mobilität im Bereich von 1000 bis 2000 cm²/(Vs), welche für verschiedene Strukturen auf der gesamten Probe homogen ist, was die Reproduzierbarkeit dieses Herstellungsverfahrens hervorhebt, sowie dessen Potential für die Implementierung in zukünftigen Technologien, welche auf epitaktischgewachsenene GNRs basieren. / Monolayer graphene nanoribbons (GNRs) were synthesized on SiC(0001) substrates with two different miscut angles at temperatures ranging from 1410 to 1460 °C. The GNR growth in lower step heights is best described by an exponential growth rate, which is correlated with the energy barrier for Si out-diffusion. On the other hand, a non-exponential rate is observed for substrates with higher steps, which is associated with the formation of few-layer graphene on the step edges. Oxygen intercalation of epitaxial GNRs is investigated next by air annealing ribbons grown in different SiC(0001) substrates. Besides the conversion of monolayer into bilayer graphene near the step edges of SiC, the oxygen intercalation also leads to the formation of an oxide layer on the terraces of the substrate, leaving the bilayer GNRs electronically isolated from each other. Electrical characterization of bilayer GNRs reveals that the ribbons are electrically decoupled from the substrate by the oxygen treatment. A robust hole concentration of around 1x10¹³ cm-² and mobilities up to 700 cm²/(Vs) at room temperature are measured for GNRs whose typical width is 100 nm. Well defined mesa structures patterned by electron beam lithography on the surface of SiC substrates is lastly researched. Transport characterization of GNRs grown on the sidewalls of the patterned terraces shows a mobility in the range of 1000 – 2000 cm²/(Vs), which is homogeneous for various structures throughout the sample, indicating the reproducibility of this fabrication method and its potential for implementation in future technologies based on epitaxially grown GNRs.

Hintergrund: Der Einsatz minimal invasiver Techniken in der onkologischen Chirurgie wird wegen der Berichte über Trokarmetastasen kontrovers diskutiert. Die Pathogenese von Inzisionsmetastasen und intraperitonealem Tumorwachstum ist bisher nicht bekannt. Als mögliche Ursachen kommen bei Einsatz der laparoskopischen Chirurgie auch Einflüsse von Gas und Druck auf das Peritoneum in Betracht. Dabei könnte eine peritoneale Inflammation die Adhäsion und das Wachstum von Tumorzellen begünstigen. Wir untersuchten den Einfluss eines CO2- und Helium- Pneumoperitoneums auf die Morphologie des Rattenperitoneums. Methoden: Bei insgesamt 50 Ratten (BD IX) erfolgte die intraabdominelle Injektion von Tumorzellen (DHB/TRb) und im Anschluß für 30 min der Aufbau eines CO2-oder Helium-Pneumoperitoneums mit einem Druck von 15 mm Hg. Nach definierten Zeitpunkten (2, 12, 24, 48 und 96h) wurden die Tiere geopfert und Proben des Peritoneums rasterelektronenmikroskopisch auf inflammatorische Veränderungen untersucht. Bei den Kontrolltieren wurde keine Pneumoperitoneum aufgebaut. Ergebnisse: Bei allen Kontrolltieren war das Peritoneum frei von entzündlichen Veränderungen. Sowohl in der CO2 als auch in der Helium-Gruppe lagen bei 21 von 25 Tieren ebenfalls keine entzündlichen Veränderungen vor. Lediglich bei vier Tieren jeder Gruppe fanden sich Alterationen des Mesothel, die auf eine Inflammation hindeuteten. Tumorzellen wurden in insgesamt sechs Tieren nachgewiesen. In keinem Fall kam es zu einem nodulären oder diffusen intraperitonealen Tumorwachstum. Schlussfolgerung: Morphologisch zeigt das Rattenperitoneum nach Tumorzellinjektion und CO2- bzw. Helium- Pneumoperitoneum keine Veränderungen, die ein intraperitoneales Tumorwachstum begünstigen könnten. Alterationen des Peritoneums infolge eines Pneumoperitoneums scheinen daher nicht die Ursache für das Auftreten von Metastasen nach minimal-invasiven Operationen zu sein. / Objective: Laparoscopic surgery in patients with cancer has been discussed controversially because of the susceptibility of laparoscopic incisions for metastatic tumour growth. The mechanisms of port-site metastases and intraperitoneal tumour growth are still unknown. One reason might be the influence of insufflation gas and pressure on the peritoneum. A structural damage of the mesothelial layer due to the pneumoperitoneum might facilitate tumour cell adhesion and growth. We have examined the influence of CO2- and helium- pneumoperitoneum on the morphology of the peritoneum. Methods: A total of 50 rats (BD IX) received colon carcinoma (DHB/TRb) cells intraperitoneally and CO2 or Helium were used for insufflation at a pressure of 15 mm Hg for 30 minutes. After different time periods (2, 12, 24, 48 and 96h) rats were killed and the peritoneum was examined by scanning electron microscopy. Controls were without pneumoperitoneum. The peritoneum was examined by scanning electron microscopy. Results: Controls and most of the rats with pneumoperitoneum showed no peritoneal alterations. In 4 animals of each group inflammatory alterations of the peritoneum such as bulging and retraction of mesothelial cells were observed at different time points. Tumour cells adherent to the peritoneum were found in a total of 6 animals. Peritoneal carcinomatosis, tumour nodules or infiltration of the peritoneum by tumour cells were not observed. Conclusions: Our study demonstrates that the morphologic integrity of the rat peritoneum is not disturbed when CO2 or helium are used for insufflation combined with the intraperitoneal injection of carcinoma cells. Pneumoperitoneum therefore is probably not the condition causing peritoneal changes that favour intraperitoneal tumour growth.

Photoelectrodes and photovoltaic devices have been prepared via multiple thin film deposition methods. Aerosol assisted chemical vapour deposition (AACVD), electrodeposition (ED), chemical bath deposition (CBD) and doctor blade technique (DB) have been used to deposit binary and ternary metal oxide films on FTO glass substrates. The prepared thin films were characterised by a combination of SEM (Scanning Electron Microscopy), powder X-ray diffraction, mechanical strength tests and photochemical measurements. Nickel oxide (NiO) thin films prepared by AACVD were determined to have good mechanical strength . with a photocurrent of 7.6 μA cm-2 at 0 V and an onset potential of about 0.10 V. This contrasted with the dark current density of 0.3 μA cm-2 at 0 V. These NiO samples have very high porosity with crystalline columns evidenced by SEM. In comparison with the AACVD methodology, NiO films prepared using a combination of ED and DB show good mechanical strength but a higher photocurrent of 24 μA cm-2 at 0 V and an onset potential of about 0.10 V with a significantly greater dark current density of 7 μA cm-2 at 0 V. The characteristic features shown in the SEM are smaller pores compared to the AACVD method. Copper (II) oxide (CuO) and copper (I) oxide (Cu2O) films were fabricated by AACVD by varying the annealing temperature between 100-325°C in air using a fixed annealing time of 30 min. It was shown by photocurrent density (J-V) measurements that CuO produced at 325 °C was most stable and provided the highest photocurrent of 173 μA cm-2 at 0 V with an onset potential of about 0.23 V. The alignment of zinc oxide (ZnO) nano-rods and nano-tubes fabricated by CBD have been shown to be strongly affected by the seed layer on the FTO substrate. SEM images showed that AACVD provided the best seed layer for aligning the growth of the nano-rods perpendicular to the surface. Nano-rods were successfully altered into nano-tubes using a potassium chloride bath etching method. NiO prepared by both AACVD and the combined ED/DB method were sensitized to absorb more of the solar spectrum using AACVD to deposit CuO over the NiO. A large increase in the photocurrent was observed for the p-type photoelectrode. These p-type photoelectrode showed a photocurrent density of approximately 100 μA cm-2 at 0 V and an onset potential of 0.3 V. This photocathode was then used as a base to produce a solid state p-type solar cell. For the construction of the solid state solar cells several n-type semiconductors were used, these were ZnO, WO3 and BiVO4. WO3 and BiVO4 were successfully produced with BiVO4 proving to be the optimum choice. This cell was then studied more in depth and optimised by controlling the thickness of each layer and annealing temperatures. The best solid state solar cell produced had a Jsc of 0.541 μA cm-2 (541 nA) and a Voc of 0.14 V, TX146 made up of NiO 20 min, CuFe2O4 50 min, CuO 10 min, BiVO4 27 min, using AACVD and then annealed for 30 min at 600°C.